// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2007 Oracle. All rights reserved. */ #include #include #include #include #include #include #include #include #include #include "misc.h" #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "volumes.h" #include "raid56.h" #include "rcu-string.h" #include "dev-replace.h" #include "sysfs.h" #include "tree-checker.h" #include "space-info.h" #include "block-group.h" #include "discard.h" #include "zoned.h" #include "fs.h" #include "accessors.h" #include "uuid-tree.h" #include "ioctl.h" #include "relocation.h" #include "scrub.h" #include "super.h" #include "raid-stripe-tree.h" #define BTRFS_BLOCK_GROUP_STRIPE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \ BTRFS_BLOCK_GROUP_RAID10 | \ BTRFS_BLOCK_GROUP_RAID56_MASK) struct btrfs_io_geometry { u32 stripe_index; u32 stripe_nr; int mirror_num; int num_stripes; u64 stripe_offset; u64 raid56_full_stripe_start; int max_errors; enum btrfs_map_op op; }; const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { [BTRFS_RAID_RAID10] = { .sub_stripes = 2, .dev_stripes = 1, .devs_max = 0, /* 0 == as many as possible */ .devs_min = 2, .tolerated_failures = 1, .devs_increment = 2, .ncopies = 2, .nparity = 0, .raid_name = "raid10", .bg_flag = BTRFS_BLOCK_GROUP_RAID10, .mindev_error = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET, }, [BTRFS_RAID_RAID1] = { .sub_stripes = 1, .dev_stripes = 1, .devs_max = 2, .devs_min = 2, .tolerated_failures = 1, .devs_increment = 2, .ncopies = 2, .nparity = 0, .raid_name = "raid1", .bg_flag = BTRFS_BLOCK_GROUP_RAID1, .mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET, }, [BTRFS_RAID_RAID1C3] = { .sub_stripes = 1, .dev_stripes = 1, .devs_max = 3, .devs_min = 3, .tolerated_failures = 2, .devs_increment = 3, .ncopies = 3, .nparity = 0, .raid_name = "raid1c3", .bg_flag = BTRFS_BLOCK_GROUP_RAID1C3, .mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET, }, [BTRFS_RAID_RAID1C4] = { .sub_stripes = 1, .dev_stripes = 1, .devs_max = 4, .devs_min = 4, .tolerated_failures = 3, .devs_increment = 4, .ncopies = 4, .nparity = 0, .raid_name = "raid1c4", .bg_flag = BTRFS_BLOCK_GROUP_RAID1C4, .mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET, }, [BTRFS_RAID_DUP] = { .sub_stripes = 1, .dev_stripes = 2, .devs_max = 1, .devs_min = 1, .tolerated_failures = 0, .devs_increment = 1, .ncopies = 2, .nparity = 0, .raid_name = "dup", .bg_flag = BTRFS_BLOCK_GROUP_DUP, .mindev_error = 0, }, [BTRFS_RAID_RAID0] = { .sub_stripes = 1, .dev_stripes = 1, .devs_max = 0, .devs_min = 1, .tolerated_failures = 0, .devs_increment = 1, .ncopies = 1, .nparity = 0, .raid_name = "raid0", .bg_flag = BTRFS_BLOCK_GROUP_RAID0, .mindev_error = 0, }, [BTRFS_RAID_SINGLE] = { .sub_stripes = 1, .dev_stripes = 1, .devs_max = 1, .devs_min = 1, .tolerated_failures = 0, .devs_increment = 1, .ncopies = 1, .nparity = 0, .raid_name = "single", .bg_flag = 0, .mindev_error = 0, }, [BTRFS_RAID_RAID5] = { .sub_stripes = 1, .dev_stripes = 1, .devs_max = 0, .devs_min = 2, .tolerated_failures = 1, .devs_increment = 1, .ncopies = 1, .nparity = 1, .raid_name = "raid5", .bg_flag = BTRFS_BLOCK_GROUP_RAID5, .mindev_error = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET, }, [BTRFS_RAID_RAID6] = { .sub_stripes = 1, .dev_stripes = 1, .devs_max = 0, .devs_min = 3, .tolerated_failures = 2, .devs_increment = 1, .ncopies = 1, .nparity = 2, .raid_name = "raid6", .bg_flag = BTRFS_BLOCK_GROUP_RAID6, .mindev_error = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET, }, }; /* * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which * can be used as index to access btrfs_raid_array[]. */ enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags) { const u64 profile = (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK); if (!profile) return BTRFS_RAID_SINGLE; return BTRFS_BG_FLAG_TO_INDEX(profile); } const char *btrfs_bg_type_to_raid_name(u64 flags) { const int index = btrfs_bg_flags_to_raid_index(flags); if (index >= BTRFS_NR_RAID_TYPES) return NULL; return btrfs_raid_array[index].raid_name; } int btrfs_nr_parity_stripes(u64 type) { enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(type); return btrfs_raid_array[index].nparity; } /* * Fill @buf with textual description of @bg_flags, no more than @size_buf * bytes including terminating null byte. */ void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf) { int i; int ret; char *bp = buf; u64 flags = bg_flags; u32 size_bp = size_buf; if (!flags) { strcpy(bp, "NONE"); return; } #define DESCRIBE_FLAG(flag, desc) \ do { \ if (flags & (flag)) { \ ret = snprintf(bp, size_bp, "%s|", (desc)); \ if (ret < 0 || ret >= size_bp) \ goto out_overflow; \ size_bp -= ret; \ bp += ret; \ flags &= ~(flag); \ } \ } while (0) DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data"); DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system"); DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata"); DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single"); for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag, btrfs_raid_array[i].raid_name); #undef DESCRIBE_FLAG if (flags) { ret = snprintf(bp, size_bp, "0x%llx|", flags); size_bp -= ret; } if (size_bp < size_buf) buf[size_buf - size_bp - 1] = '\0'; /* remove last | */ /* * The text is trimmed, it's up to the caller to provide sufficiently * large buffer */ out_overflow:; } static int init_first_rw_device(struct btrfs_trans_handle *trans); static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info); static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); /* * Device locking * ============== * * There are several mutexes that protect manipulation of devices and low-level * structures like chunks but not block groups, extents or files * * uuid_mutex (global lock) * ------------------------ * protects the fs_uuids list that tracks all per-fs fs_devices, resulting from * the SCAN_DEV ioctl registration or from mount either implicitly (the first * device) or requested by the device= mount option * * the mutex can be very coarse and can cover long-running operations * * protects: updates to fs_devices counters like missing devices, rw devices, * seeding, structure cloning, opening/closing devices at mount/umount time * * global::fs_devs - add, remove, updates to the global list * * does not protect: manipulation of the fs_devices::devices list in general * but in mount context it could be used to exclude list modifications by eg. * scan ioctl * * btrfs_device::name - renames (write side), read is RCU * * fs_devices::device_list_mutex (per-fs, with RCU) * ------------------------------------------------ * protects updates to fs_devices::devices, ie. adding and deleting * * simple list traversal with read-only actions can be done with RCU protection * * may be used to exclude some operations from running concurrently without any * modifications to the list (see write_all_supers) * * Is not required at mount and close times, because our device list is * protected by the uuid_mutex at that point. * * balance_mutex * ------------- * protects balance structures (status, state) and context accessed from * several places (internally, ioctl) * * chunk_mutex * ----------- * protects chunks, adding or removing during allocation, trim or when a new * device is added/removed. Additionally it also protects post_commit_list of * individual devices, since they can be added to the transaction's * post_commit_list only with chunk_mutex held. * * cleaner_mutex * ------------- * a big lock that is held by the cleaner thread and prevents running subvolume * cleaning together with relocation or delayed iputs * * * Lock nesting * ============ * * uuid_mutex * device_list_mutex * chunk_mutex * balance_mutex * * * Exclusive operations * ==================== * * Maintains the exclusivity of the following operations that apply to the * whole filesystem and cannot run in parallel. * * - Balance (*) * - Device add * - Device remove * - Device replace (*) * - Resize * * The device operations (as above) can be in one of the following states: * * - Running state * - Paused state * - Completed state * * Only device operations marked with (*) can go into the Paused state for the * following reasons: * * - ioctl (only Balance can be Paused through ioctl) * - filesystem remounted as read-only * - filesystem unmounted and mounted as read-only * - system power-cycle and filesystem mounted as read-only * - filesystem or device errors leading to forced read-only * * The status of exclusive operation is set and cleared atomically. * During the course of Paused state, fs_info::exclusive_operation remains set. * A device operation in Paused or Running state can be canceled or resumed * either by ioctl (Balance only) or when remounted as read-write. * The exclusive status is cleared when the device operation is canceled or * completed. */ DEFINE_MUTEX(uuid_mutex); static LIST_HEAD(fs_uuids); struct list_head * __attribute_const__ btrfs_get_fs_uuids(void) { return &fs_uuids; } /* * Allocate new btrfs_fs_devices structure identified by a fsid. * * @fsid: if not NULL, copy the UUID to fs_devices::fsid and to * fs_devices::metadata_fsid * * Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR(). * The returned struct is not linked onto any lists and can be destroyed with * kfree() right away. */ static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid) { struct btrfs_fs_devices *fs_devs; fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL); if (!fs_devs) return ERR_PTR(-ENOMEM); mutex_init(&fs_devs->device_list_mutex); INIT_LIST_HEAD(&fs_devs->devices); INIT_LIST_HEAD(&fs_devs->alloc_list); INIT_LIST_HEAD(&fs_devs->fs_list); INIT_LIST_HEAD(&fs_devs->seed_list); if (fsid) { memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE); memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE); } return fs_devs; } static void btrfs_free_device(struct btrfs_device *device) { WARN_ON(!list_empty(&device->post_commit_list)); rcu_string_free(device->name); extent_io_tree_release(&device->alloc_state); btrfs_destroy_dev_zone_info(device); kfree(device); } static void free_fs_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device; WARN_ON(fs_devices->opened); while (!list_empty(&fs_devices->devices)) { device = list_entry(fs_devices->devices.next, struct btrfs_device, dev_list); list_del(&device->dev_list); btrfs_free_device(device); } kfree(fs_devices); } void __exit btrfs_cleanup_fs_uuids(void) { struct btrfs_fs_devices *fs_devices; while (!list_empty(&fs_uuids)) { fs_devices = list_entry(fs_uuids.next, struct btrfs_fs_devices, fs_list); list_del(&fs_devices->fs_list); free_fs_devices(fs_devices); } } static bool match_fsid_fs_devices(const struct btrfs_fs_devices *fs_devices, const u8 *fsid, const u8 *metadata_fsid) { if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) != 0) return false; if (!metadata_fsid) return true; if (memcmp(metadata_fsid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE) != 0) return false; return true; } static noinline struct btrfs_fs_devices *find_fsid( const u8 *fsid, const u8 *metadata_fsid) { struct btrfs_fs_devices *fs_devices; ASSERT(fsid); /* Handle non-split brain cases */ list_for_each_entry(fs_devices, &fs_uuids, fs_list) { if (match_fsid_fs_devices(fs_devices, fsid, metadata_fsid)) return fs_devices; } return NULL; } static int btrfs_get_bdev_and_sb(const char *device_path, blk_mode_t flags, void *holder, int flush, struct file **bdev_file, struct btrfs_super_block **disk_super) { struct block_device *bdev; int ret; *bdev_file = bdev_file_open_by_path(device_path, flags, holder, NULL); if (IS_ERR(*bdev_file)) { ret = PTR_ERR(*bdev_file); goto error; } bdev = file_bdev(*bdev_file); if (flush) sync_blockdev(bdev); ret = set_blocksize(bdev, BTRFS_BDEV_BLOCKSIZE); if (ret) { fput(*bdev_file); goto error; } invalidate_bdev(bdev); *disk_super = btrfs_read_dev_super(bdev); if (IS_ERR(*disk_super)) { ret = PTR_ERR(*disk_super); fput(*bdev_file); goto error; } return 0; error: *bdev_file = NULL; return ret; } /* * Search and remove all stale devices (which are not mounted). When both * inputs are NULL, it will search and release all stale devices. * * @devt: Optional. When provided will it release all unmounted devices * matching this devt only. * @skip_device: Optional. Will skip this device when searching for the stale * devices. * * Return: 0 for success or if @devt is 0. * -EBUSY if @devt is a mounted device. * -ENOENT if @devt does not match any device in the list. */ static int btrfs_free_stale_devices(dev_t devt, struct btrfs_device *skip_device) { struct btrfs_fs_devices *fs_devices, *tmp_fs_devices; struct btrfs_device *device, *tmp_device; int ret; bool freed = false; lockdep_assert_held(&uuid_mutex); /* Return good status if there is no instance of devt. */ ret = 0; list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) { mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry_safe(device, tmp_device, &fs_devices->devices, dev_list) { if (skip_device && skip_device == device) continue; if (devt && devt != device->devt) continue; if (fs_devices->opened) { if (devt) ret = -EBUSY; break; } /* delete the stale device */ fs_devices->num_devices--; list_del(&device->dev_list); btrfs_free_device(device); freed = true; } mutex_unlock(&fs_devices->device_list_mutex); if (fs_devices->num_devices == 0) { btrfs_sysfs_remove_fsid(fs_devices); list_del(&fs_devices->fs_list); free_fs_devices(fs_devices); } } /* If there is at least one freed device return 0. */ if (freed) return 0; return ret; } static struct btrfs_fs_devices *find_fsid_by_device( struct btrfs_super_block *disk_super, dev_t devt, bool *same_fsid_diff_dev) { struct btrfs_fs_devices *fsid_fs_devices; struct btrfs_fs_devices *devt_fs_devices; const bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) & BTRFS_FEATURE_INCOMPAT_METADATA_UUID); bool found_by_devt = false; /* Find the fs_device by the usual method, if found use it. */ fsid_fs_devices = find_fsid(disk_super->fsid, has_metadata_uuid ? disk_super->metadata_uuid : NULL); /* The temp_fsid feature is supported only with single device filesystem. */ if (btrfs_super_num_devices(disk_super) != 1) return fsid_fs_devices; /* * A seed device is an integral component of the sprout device, which * functions as a multi-device filesystem. So, temp-fsid feature is * not supported. */ if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) return fsid_fs_devices; /* Try to find a fs_devices by matching devt. */ list_for_each_entry(devt_fs_devices, &fs_uuids, fs_list) { struct btrfs_device *device; list_for_each_entry(device, &devt_fs_devices->devices, dev_list) { if (device->devt == devt) { found_by_devt = true; break; } } if (found_by_devt) break; } if (found_by_devt) { /* Existing device. */ if (fsid_fs_devices == NULL) { if (devt_fs_devices->opened == 0) { /* Stale device. */ return NULL; } else { /* temp_fsid is mounting a subvol. */ return devt_fs_devices; } } else { /* Regular or temp_fsid device mounting a subvol. */ return devt_fs_devices; } } else { /* New device. */ if (fsid_fs_devices == NULL) { return NULL; } else { /* sb::fsid is already used create a new temp_fsid. */ *same_fsid_diff_dev = true; return NULL; } } /* Not reached. */ } /* * This is only used on mount, and we are protected from competing things * messing with our fs_devices by the uuid_mutex, thus we do not need the * fs_devices->device_list_mutex here. */ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices, struct btrfs_device *device, blk_mode_t flags, void *holder) { struct file *bdev_file; struct btrfs_super_block *disk_super; u64 devid; int ret; if (device->bdev) return -EINVAL; if (!device->name) return -EINVAL; ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, &bdev_file, &disk_super); if (ret) return ret; devid = btrfs_stack_device_id(&disk_super->dev_item); if (devid != device->devid) goto error_free_page; if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE)) goto error_free_page; device->generation = btrfs_super_generation(disk_super); if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { if (btrfs_super_incompat_flags(disk_super) & BTRFS_FEATURE_INCOMPAT_METADATA_UUID) { pr_err( "BTRFS: Invalid seeding and uuid-changed device detected\n"); goto error_free_page; } clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); fs_devices->seeding = true; } else { if (bdev_read_only(file_bdev(bdev_file))) clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); else set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); } if (!bdev_nonrot(file_bdev(bdev_file))) fs_devices->rotating = true; if (bdev_max_discard_sectors(file_bdev(bdev_file))) fs_devices->discardable = true; device->bdev_file = bdev_file; device->bdev = file_bdev(bdev_file); clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); fs_devices->open_devices++; if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && device->devid != BTRFS_DEV_REPLACE_DEVID) { fs_devices->rw_devices++; list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list); } btrfs_release_disk_super(disk_super); return 0; error_free_page: btrfs_release_disk_super(disk_super); fput(bdev_file); return -EINVAL; } u8 *btrfs_sb_fsid_ptr(struct btrfs_super_block *sb) { bool has_metadata_uuid = (btrfs_super_incompat_flags(sb) & BTRFS_FEATURE_INCOMPAT_METADATA_UUID); return has_metadata_uuid ? sb->metadata_uuid : sb->fsid; } /* * Add new device to list of registered devices * * Returns: * device pointer which was just added or updated when successful * error pointer when failed */ static noinline struct btrfs_device *device_list_add(const char *path, struct btrfs_super_block *disk_super, bool *new_device_added) { struct btrfs_device *device; struct btrfs_fs_devices *fs_devices = NULL; struct rcu_string *name; u64 found_transid = btrfs_super_generation(disk_super); u64 devid = btrfs_stack_device_id(&disk_super->dev_item); dev_t path_devt; int error; bool same_fsid_diff_dev = false; bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) & BTRFS_FEATURE_INCOMPAT_METADATA_UUID); if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) { btrfs_err(NULL, "device %s has incomplete metadata_uuid change, please use btrfstune to complete", path); return ERR_PTR(-EAGAIN); } error = lookup_bdev(path, &path_devt); if (error) { btrfs_err(NULL, "failed to lookup block device for path %s: %d", path, error); return ERR_PTR(error); } fs_devices = find_fsid_by_device(disk_super, path_devt, &same_fsid_diff_dev); if (!fs_devices) { fs_devices = alloc_fs_devices(disk_super->fsid); if (IS_ERR(fs_devices)) return ERR_CAST(fs_devices); if (has_metadata_uuid) memcpy(fs_devices->metadata_uuid, disk_super->metadata_uuid, BTRFS_FSID_SIZE); if (same_fsid_diff_dev) { generate_random_uuid(fs_devices->fsid); fs_devices->temp_fsid = true; pr_info("BTRFS: device %s (%d:%d) using temp-fsid %pU\n", path, MAJOR(path_devt), MINOR(path_devt), fs_devices->fsid); } mutex_lock(&fs_devices->device_list_mutex); list_add(&fs_devices->fs_list, &fs_uuids); device = NULL; } else { struct btrfs_dev_lookup_args args = { .devid = devid, .uuid = disk_super->dev_item.uuid, }; mutex_lock(&fs_devices->device_list_mutex); device = btrfs_find_device(fs_devices, &args); if (found_transid > fs_devices->latest_generation) { memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); memcpy(fs_devices->metadata_uuid, btrfs_sb_fsid_ptr(disk_super), BTRFS_FSID_SIZE); } } if (!device) { unsigned int nofs_flag; if (fs_devices->opened) { btrfs_err(NULL, "device %s (%d:%d) belongs to fsid %pU, and the fs is already mounted, scanned by %s (%d)", path, MAJOR(path_devt), MINOR(path_devt), fs_devices->fsid, current->comm, task_pid_nr(current)); mutex_unlock(&fs_devices->device_list_mutex); return ERR_PTR(-EBUSY); } nofs_flag = memalloc_nofs_save(); device = btrfs_alloc_device(NULL, &devid, disk_super->dev_item.uuid, path); memalloc_nofs_restore(nofs_flag); if (IS_ERR(device)) { mutex_unlock(&fs_devices->device_list_mutex); /* we can safely leave the fs_devices entry around */ return device; } device->devt = path_devt; list_add_rcu(&device->dev_list, &fs_devices->devices); fs_devices->num_devices++; device->fs_devices = fs_devices; *new_device_added = true; if (disk_super->label[0]) pr_info( "BTRFS: device label %s devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n", disk_super->label, devid, found_transid, path, MAJOR(path_devt), MINOR(path_devt), current->comm, task_pid_nr(current)); else pr_info( "BTRFS: device fsid %pU devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n", disk_super->fsid, devid, found_transid, path, MAJOR(path_devt), MINOR(path_devt), current->comm, task_pid_nr(current)); } else if (!device->name || strcmp(device->name->str, path)) { /* * When FS is already mounted. * 1. If you are here and if the device->name is NULL that * means this device was missing at time of FS mount. * 2. If you are here and if the device->name is different * from 'path' that means either * a. The same device disappeared and reappeared with * different name. or * b. The missing-disk-which-was-replaced, has * reappeared now. * * We must allow 1 and 2a above. But 2b would be a spurious * and unintentional. * * Further in case of 1 and 2a above, the disk at 'path' * would have missed some transaction when it was away and * in case of 2a the stale bdev has to be updated as well. * 2b must not be allowed at all time. */ /* * For now, we do allow update to btrfs_fs_device through the * btrfs dev scan cli after FS has been mounted. We're still * tracking a problem where systems fail mount by subvolume id * when we reject replacement on a mounted FS. */ if (!fs_devices->opened && found_transid < device->generation) { /* * That is if the FS is _not_ mounted and if you * are here, that means there is more than one * disk with same uuid and devid.We keep the one * with larger generation number or the last-in if * generation are equal. */ mutex_unlock(&fs_devices->device_list_mutex); btrfs_err(NULL, "device %s already registered with a higher generation, found %llu expect %llu", path, found_transid, device->generation); return ERR_PTR(-EEXIST); } /* * We are going to replace the device path for a given devid, * make sure it's the same device if the device is mounted * * NOTE: the device->fs_info may not be reliable here so pass * in a NULL to message helpers instead. This avoids a possible * use-after-free when the fs_info and fs_info->sb are already * torn down. */ if (device->bdev) { if (device->devt != path_devt) { mutex_unlock(&fs_devices->device_list_mutex); btrfs_warn_in_rcu(NULL, "duplicate device %s devid %llu generation %llu scanned by %s (%d)", path, devid, found_transid, current->comm, task_pid_nr(current)); return ERR_PTR(-EEXIST); } btrfs_info_in_rcu(NULL, "devid %llu device path %s changed to %s scanned by %s (%d)", devid, btrfs_dev_name(device), path, current->comm, task_pid_nr(current)); } name = rcu_string_strdup(path, GFP_NOFS); if (!name) { mutex_unlock(&fs_devices->device_list_mutex); return ERR_PTR(-ENOMEM); } rcu_string_free(device->name); rcu_assign_pointer(device->name, name); if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) { fs_devices->missing_devices--; clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); } device->devt = path_devt; } /* * Unmount does not free the btrfs_device struct but would zero * generation along with most of the other members. So just update * it back. We need it to pick the disk with largest generation * (as above). */ if (!fs_devices->opened) { device->generation = found_transid; fs_devices->latest_generation = max_t(u64, found_transid, fs_devices->latest_generation); } fs_devices->total_devices = btrfs_super_num_devices(disk_super); mutex_unlock(&fs_devices->device_list_mutex); return device; } static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) { struct btrfs_fs_devices *fs_devices; struct btrfs_device *device; struct btrfs_device *orig_dev; int ret = 0; lockdep_assert_held(&uuid_mutex); fs_devices = alloc_fs_devices(orig->fsid); if (IS_ERR(fs_devices)) return fs_devices; fs_devices->total_devices = orig->total_devices; list_for_each_entry(orig_dev, &orig->devices, dev_list) { const char *dev_path = NULL; /* * This is ok to do without RCU read locked because we hold the * uuid mutex so nothing we touch in here is going to disappear. */ if (orig_dev->name) dev_path = orig_dev->name->str; device = btrfs_alloc_device(NULL, &orig_dev->devid, orig_dev->uuid, dev_path); if (IS_ERR(device)) { ret = PTR_ERR(device); goto error; } if (orig_dev->zone_info) { struct btrfs_zoned_device_info *zone_info; zone_info = btrfs_clone_dev_zone_info(orig_dev); if (!zone_info) { btrfs_free_device(device); ret = -ENOMEM; goto error; } device->zone_info = zone_info; } list_add(&device->dev_list, &fs_devices->devices); device->fs_devices = fs_devices; fs_devices->num_devices++; } return fs_devices; error: free_fs_devices(fs_devices); return ERR_PTR(ret); } static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, struct btrfs_device **latest_dev) { struct btrfs_device *device, *next; /* This is the initialized path, it is safe to release the devices. */ list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)) { if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state) && !test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state) && (!*latest_dev || device->generation > (*latest_dev)->generation)) { *latest_dev = device; } continue; } /* * We have already validated the presence of BTRFS_DEV_REPLACE_DEVID, * in btrfs_init_dev_replace() so just continue. */ if (device->devid == BTRFS_DEV_REPLACE_DEVID) continue; if (device->bdev_file) { fput(device->bdev_file); device->bdev = NULL; device->bdev_file = NULL; fs_devices->open_devices--; } if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { list_del_init(&device->dev_alloc_list); clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); fs_devices->rw_devices--; } list_del_init(&device->dev_list); fs_devices->num_devices--; btrfs_free_device(device); } } /* * After we have read the system tree and know devids belonging to this * filesystem, remove the device which does not belong there. */ void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *latest_dev = NULL; struct btrfs_fs_devices *seed_dev; mutex_lock(&uuid_mutex); __btrfs_free_extra_devids(fs_devices, &latest_dev); list_for_each_entry(seed_dev, &fs_devices->seed_list, seed_list) __btrfs_free_extra_devids(seed_dev, &latest_dev); fs_devices->latest_dev = latest_dev; mutex_unlock(&uuid_mutex); } static void btrfs_close_bdev(struct btrfs_device *device) { if (!device->bdev) return; if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { sync_blockdev(device->bdev); invalidate_bdev(device->bdev); } fput(device->bdev_file); } static void btrfs_close_one_device(struct btrfs_device *device) { struct btrfs_fs_devices *fs_devices = device->fs_devices; if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && device->devid != BTRFS_DEV_REPLACE_DEVID) { list_del_init(&device->dev_alloc_list); fs_devices->rw_devices--; } if (device->devid == BTRFS_DEV_REPLACE_DEVID) clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) { clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); fs_devices->missing_devices--; } btrfs_close_bdev(device); if (device->bdev) { fs_devices->open_devices--; device->bdev = NULL; } clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); btrfs_destroy_dev_zone_info(device); device->fs_info = NULL; atomic_set(&device->dev_stats_ccnt, 0); extent_io_tree_release(&device->alloc_state); /* * Reset the flush error record. We might have a transient flush error * in this mount, and if so we aborted the current transaction and set * the fs to an error state, guaranteeing no super blocks can be further * committed. However that error might be transient and if we unmount the * filesystem and mount it again, we should allow the mount to succeed * (btrfs_check_rw_degradable() should not fail) - if after mounting the * filesystem again we still get flush errors, then we will again abort * any transaction and set the error state, guaranteeing no commits of * unsafe super blocks. */ device->last_flush_error = 0; /* Verify the device is back in a pristine state */ WARN_ON(test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state)); WARN_ON(test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)); WARN_ON(!list_empty(&device->dev_alloc_list)); WARN_ON(!list_empty(&device->post_commit_list)); } static void close_fs_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device, *tmp; lockdep_assert_held(&uuid_mutex); if (--fs_devices->opened > 0) return; list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) btrfs_close_one_device(device); WARN_ON(fs_devices->open_devices); WARN_ON(fs_devices->rw_devices); fs_devices->opened = 0; fs_devices->seeding = false; fs_devices->fs_info = NULL; } void btrfs_close_devices(struct btrfs_fs_devices *fs_devices) { LIST_HEAD(list); struct btrfs_fs_devices *tmp; mutex_lock(&uuid_mutex); close_fs_devices(fs_devices); if (!fs_devices->opened) { list_splice_init(&fs_devices->seed_list, &list); /* * If the struct btrfs_fs_devices is not assembled with any * other device, it can be re-initialized during the next mount * without the needing device-scan step. Therefore, it can be * fully freed. */ if (fs_devices->num_devices == 1) { list_del(&fs_devices->fs_list); free_fs_devices(fs_devices); } } list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) { close_fs_devices(fs_devices); list_del(&fs_devices->seed_list); free_fs_devices(fs_devices); } mutex_unlock(&uuid_mutex); } static int open_fs_devices(struct btrfs_fs_devices *fs_devices, blk_mode_t flags, void *holder) { struct btrfs_device *device; struct btrfs_device *latest_dev = NULL; struct btrfs_device *tmp_device; list_for_each_entry_safe(device, tmp_device, &fs_devices->devices, dev_list) { int ret; ret = btrfs_open_one_device(fs_devices, device, flags, holder); if (ret == 0 && (!latest_dev || device->generation > latest_dev->generation)) { latest_dev = device; } else if (ret == -ENODATA) { fs_devices->num_devices--; list_del(&device->dev_list); btrfs_free_device(device); } } if (fs_devices->open_devices == 0) return -EINVAL; fs_devices->opened = 1; fs_devices->latest_dev = latest_dev; fs_devices->total_rw_bytes = 0; fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR; fs_devices->read_policy = BTRFS_READ_POLICY_PID; return 0; } static int devid_cmp(void *priv, const struct list_head *a, const struct list_head *b) { const struct btrfs_device *dev1, *dev2; dev1 = list_entry(a, struct btrfs_device, dev_list); dev2 = list_entry(b, struct btrfs_device, dev_list); if (dev1->devid < dev2->devid) return -1; else if (dev1->devid > dev2->devid) return 1; return 0; } int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, blk_mode_t flags, void *holder) { int ret; lockdep_assert_held(&uuid_mutex); /* * The device_list_mutex cannot be taken here in case opening the * underlying device takes further locks like open_mutex. * * We also don't need the lock here as this is called during mount and * exclusion is provided by uuid_mutex */ if (fs_devices->opened) { fs_devices->opened++; ret = 0; } else { list_sort(NULL, &fs_devices->devices, devid_cmp); ret = open_fs_devices(fs_devices, flags, holder); } return ret; } void btrfs_release_disk_super(struct btrfs_super_block *super) { struct page *page = virt_to_page(super); put_page(page); } static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev, u64 bytenr, u64 bytenr_orig) { struct btrfs_super_block *disk_super; struct page *page; void *p; pgoff_t index; /* make sure our super fits in the device */ if (bytenr + PAGE_SIZE >= bdev_nr_bytes(bdev)) return ERR_PTR(-EINVAL); /* make sure our super fits in the page */ if (sizeof(*disk_super) > PAGE_SIZE) return ERR_PTR(-EINVAL); /* make sure our super doesn't straddle pages on disk */ index = bytenr >> PAGE_SHIFT; if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index) return ERR_PTR(-EINVAL); /* pull in the page with our super */ page = read_cache_page_gfp(bdev->bd_inode->i_mapping, index, GFP_KERNEL); if (IS_ERR(page)) return ERR_CAST(page); p = page_address(page); /* align our pointer to the offset of the super block */ disk_super = p + offset_in_page(bytenr); if (btrfs_super_bytenr(disk_super) != bytenr_orig || btrfs_super_magic(disk_super) != BTRFS_MAGIC) { btrfs_release_disk_super(p); return ERR_PTR(-EINVAL); } if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1]) disk_super->label[BTRFS_LABEL_SIZE - 1] = 0; return disk_super; } int btrfs_forget_devices(dev_t devt) { int ret; mutex_lock(&uuid_mutex); ret = btrfs_free_stale_devices(devt, NULL); mutex_unlock(&uuid_mutex); return ret; } static bool btrfs_skip_registration(struct btrfs_super_block *disk_super, const char *path, dev_t devt, bool mount_arg_dev) { struct btrfs_fs_devices *fs_devices; /* * Do not skip device registration for mounted devices with matching * maj:min but different paths. Booting without initrd relies on * /dev/root initially, later replaced with the actual root device. * A successful scan ensures grub2-probe selects the correct device. */ list_for_each_entry(fs_devices, &fs_uuids, fs_list) { struct btrfs_device *device; mutex_lock(&fs_devices->device_list_mutex); if (!fs_devices->opened) { mutex_unlock(&fs_devices->device_list_mutex); continue; } list_for_each_entry(device, &fs_devices->devices, dev_list) { if (device->bdev && (device->bdev->bd_dev == devt) && strcmp(device->name->str, path) != 0) { mutex_unlock(&fs_devices->device_list_mutex); /* Do not skip registration. */ return false; } } mutex_unlock(&fs_devices->device_list_mutex); } if (!mount_arg_dev && btrfs_super_num_devices(disk_super) == 1 && !(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING)) return true; return false; } /* * Look for a btrfs signature on a device. This may be called out of the mount path * and we are not allowed to call set_blocksize during the scan. The superblock * is read via pagecache. * * With @mount_arg_dev it's a scan during mount time that will always register * the device or return an error. Multi-device and seeding devices are registered * in both cases. */ struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags, bool mount_arg_dev) { struct btrfs_super_block *disk_super; bool new_device_added = false; struct btrfs_device *device = NULL; struct file *bdev_file; u64 bytenr, bytenr_orig; dev_t devt; int ret; lockdep_assert_held(&uuid_mutex); /* * we would like to check all the supers, but that would make * a btrfs mount succeed after a mkfs from a different FS. * So, we need to add a special mount option to scan for * later supers, using BTRFS_SUPER_MIRROR_MAX instead */ /* * Avoid an exclusive open here, as the systemd-udev may initiate the * device scan which may race with the user's mount or mkfs command, * resulting in failure. * Since the device scan is solely for reading purposes, there is no * need for an exclusive open. Additionally, the devices are read again * during the mount process. It is ok to get some inconsistent * values temporarily, as the device paths of the fsid are the only * required information for assembling the volume. */ bdev_file = bdev_file_open_by_path(path, flags, NULL, NULL); if (IS_ERR(bdev_file)) return ERR_CAST(bdev_file); bytenr_orig = btrfs_sb_offset(0); ret = btrfs_sb_log_location_bdev(file_bdev(bdev_file), 0, READ, &bytenr); if (ret) { device = ERR_PTR(ret); goto error_bdev_put; } disk_super = btrfs_read_disk_super(file_bdev(bdev_file), bytenr, bytenr_orig); if (IS_ERR(disk_super)) { device = ERR_CAST(disk_super); goto error_bdev_put; } devt = file_bdev(bdev_file)->bd_dev; if (btrfs_skip_registration(disk_super, path, devt, mount_arg_dev)) { pr_debug("BTRFS: skip registering single non-seed device %s (%d:%d)\n", path, MAJOR(devt), MINOR(devt)); btrfs_free_stale_devices(devt, NULL); device = NULL; goto free_disk_super; } device = device_list_add(path, disk_super, &new_device_added); if (!IS_ERR(device) && new_device_added) btrfs_free_stale_devices(device->devt, device); free_disk_super: btrfs_release_disk_super(disk_super); error_bdev_put: fput(bdev_file); return device; } /* * Try to find a chunk that intersects [start, start + len] range and when one * such is found, record the end of it in *start */ static bool contains_pending_extent(struct btrfs_device *device, u64 *start, u64 len) { u64 physical_start, physical_end; lockdep_assert_held(&device->fs_info->chunk_mutex); if (find_first_extent_bit(&device->alloc_state, *start, &physical_start, &physical_end, CHUNK_ALLOCATED, NULL)) { if (in_range(physical_start, *start, len) || in_range(*start, physical_start, physical_end + 1 - physical_start)) { *start = physical_end + 1; return true; } } return false; } static u64 dev_extent_search_start(struct btrfs_device *device) { switch (device->fs_devices->chunk_alloc_policy) { case BTRFS_CHUNK_ALLOC_REGULAR: return BTRFS_DEVICE_RANGE_RESERVED; case BTRFS_CHUNK_ALLOC_ZONED: /* * We don't care about the starting region like regular * allocator, because we anyway use/reserve the first two zones * for superblock logging. */ return 0; default: BUG(); } } static bool dev_extent_hole_check_zoned(struct btrfs_device *device, u64 *hole_start, u64 *hole_size, u64 num_bytes) { u64 zone_size = device->zone_info->zone_size; u64 pos; int ret; bool changed = false; ASSERT(IS_ALIGNED(*hole_start, zone_size)); while (*hole_size > 0) { pos = btrfs_find_allocatable_zones(device, *hole_start, *hole_start + *hole_size, num_bytes); if (pos != *hole_start) { *hole_size = *hole_start + *hole_size - pos; *hole_start = pos; changed = true; if (*hole_size < num_bytes) break; } ret = btrfs_ensure_empty_zones(device, pos, num_bytes); /* Range is ensured to be empty */ if (!ret) return changed; /* Given hole range was invalid (outside of device) */ if (ret == -ERANGE) { *hole_start += *hole_size; *hole_size = 0; return true; } *hole_start += zone_size; *hole_size -= zone_size; changed = true; } return changed; } /* * Check if specified hole is suitable for allocation. * * @device: the device which we have the hole * @hole_start: starting position of the hole * @hole_size: the size of the hole * @num_bytes: the size of the free space that we need * * This function may modify @hole_start and @hole_size to reflect the suitable * position for allocation. Returns 1 if hole position is updated, 0 otherwise. */ static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start, u64 *hole_size, u64 num_bytes) { bool changed = false; u64 hole_end = *hole_start + *hole_size; for (;;) { /* * Check before we set max_hole_start, otherwise we could end up * sending back this offset anyway. */ if (contains_pending_extent(device, hole_start, *hole_size)) { if (hole_end >= *hole_start) *hole_size = hole_end - *hole_start; else *hole_size = 0; changed = true; } switch (device->fs_devices->chunk_alloc_policy) { case BTRFS_CHUNK_ALLOC_REGULAR: /* No extra check */ break; case BTRFS_CHUNK_ALLOC_ZONED: if (dev_extent_hole_check_zoned(device, hole_start, hole_size, num_bytes)) { changed = true; /* * The changed hole can contain pending extent. * Loop again to check that. */ continue; } break; default: BUG(); } break; } return changed; } /* * Find free space in the specified device. * * @device: the device which we search the free space in * @num_bytes: the size of the free space that we need * @search_start: the position from which to begin the search * @start: store the start of the free space. * @len: the size of the free space. that we find, or the size * of the max free space if we don't find suitable free space * * This does a pretty simple search, the expectation is that it is called very * infrequently and that a given device has a small number of extents. * * @start is used to store the start of the free space if we find. But if we * don't find suitable free space, it will be used to store the start position * of the max free space. * * @len is used to store the size of the free space that we find. * But if we don't find suitable free space, it is used to store the size of * the max free space. * * NOTE: This function will search *commit* root of device tree, and does extra * check to ensure dev extents are not double allocated. * This makes the function safe to allocate dev extents but may not report * correct usable device space, as device extent freed in current transaction * is not reported as available. */ static int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, u64 *start, u64 *len) { struct btrfs_fs_info *fs_info = device->fs_info; struct btrfs_root *root = fs_info->dev_root; struct btrfs_key key; struct btrfs_dev_extent *dev_extent; struct btrfs_path *path; u64 search_start; u64 hole_size; u64 max_hole_start; u64 max_hole_size = 0; u64 extent_end; u64 search_end = device->total_bytes; int ret; int slot; struct extent_buffer *l; search_start = dev_extent_search_start(device); max_hole_start = search_start; WARN_ON(device->zone_info && !IS_ALIGNED(num_bytes, device->zone_info->zone_size)); path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } again: if (search_start >= search_end || test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { ret = -ENOSPC; goto out; } path->reada = READA_FORWARD; path->search_commit_root = 1; path->skip_locking = 1; key.objectid = device->devid; key.offset = search_start; key.type = BTRFS_DEV_EXTENT_KEY; ret = btrfs_search_backwards(root, &key, path); if (ret < 0) goto out; while (search_start < search_end) { l = path->nodes[0]; slot = path->slots[0]; if (slot >= btrfs_header_nritems(l)) { ret = btrfs_next_leaf(root, path); if (ret == 0) continue; if (ret < 0) goto out; break; } btrfs_item_key_to_cpu(l, &key, slot); if (key.objectid < device->devid) goto next; if (key.objectid > device->devid) break; if (key.type != BTRFS_DEV_EXTENT_KEY) goto next; if (key.offset > search_end) break; if (key.offset > search_start) { hole_size = key.offset - search_start; dev_extent_hole_check(device, &search_start, &hole_size, num_bytes); if (hole_size > max_hole_size) { max_hole_start = search_start; max_hole_size = hole_size; } /* * If this free space is greater than which we need, * it must be the max free space that we have found * until now, so max_hole_start must point to the start * of this free space and the length of this free space * is stored in max_hole_size. Thus, we return * max_hole_start and max_hole_size and go back to the * caller. */ if (hole_size >= num_bytes) { ret = 0; goto out; } } dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); extent_end = key.offset + btrfs_dev_extent_length(l, dev_extent); if (extent_end > search_start) search_start = extent_end; next: path->slots[0]++; cond_resched(); } /* * At this point, search_start should be the end of * allocated dev extents, and when shrinking the device, * search_end may be smaller than search_start. */ if (search_end > search_start) { hole_size = search_end - search_start; if (dev_extent_hole_check(device, &search_start, &hole_size, num_bytes)) { btrfs_release_path(path); goto again; } if (hole_size > max_hole_size) { max_hole_start = search_start; max_hole_size = hole_size; } } /* See above. */ if (max_hole_size < num_bytes) ret = -ENOSPC; else ret = 0; ASSERT(max_hole_start + max_hole_size <= search_end); out: btrfs_free_path(path); *start = max_hole_start; if (len) *len = max_hole_size; return ret; } static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 start, u64 *dev_extent_len) { struct btrfs_fs_info *fs_info = device->fs_info; struct btrfs_root *root = fs_info->dev_root; int ret; struct btrfs_path *path; struct btrfs_key key; struct btrfs_key found_key; struct extent_buffer *leaf = NULL; struct btrfs_dev_extent *extent = NULL; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = device->devid; key.offset = start; key.type = BTRFS_DEV_EXTENT_KEY; again: ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret > 0) { ret = btrfs_previous_item(root, path, key.objectid, BTRFS_DEV_EXTENT_KEY); if (ret) goto out; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); extent = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_extent); BUG_ON(found_key.offset > start || found_key.offset + btrfs_dev_extent_length(leaf, extent) < start); key = found_key; btrfs_release_path(path); goto again; } else if (ret == 0) { leaf = path->nodes[0]; extent = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_extent); } else { goto out; } *dev_extent_len = btrfs_dev_extent_length(leaf, extent); ret = btrfs_del_item(trans, root, path); if (ret == 0) set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags); out: btrfs_free_path(path); return ret; } static u64 find_next_chunk(struct btrfs_fs_info *fs_info) { struct rb_node *n; u64 ret = 0; read_lock(&fs_info->mapping_tree_lock); n = rb_last(&fs_info->mapping_tree.rb_root); if (n) { struct btrfs_chunk_map *map; map = rb_entry(n, struct btrfs_chunk_map, rb_node); ret = map->start + map->chunk_len; } read_unlock(&fs_info->mapping_tree_lock); return ret; } static noinline int find_next_devid(struct btrfs_fs_info *fs_info, u64 *devid_ret) { int ret; struct btrfs_key key; struct btrfs_key found_key; struct btrfs_path *path; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.type = BTRFS_DEV_ITEM_KEY; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0); if (ret < 0) goto error; if (ret == 0) { /* Corruption */ btrfs_err(fs_info, "corrupted chunk tree devid -1 matched"); ret = -EUCLEAN; goto error; } ret = btrfs_previous_item(fs_info->chunk_root, path, BTRFS_DEV_ITEMS_OBJECTID, BTRFS_DEV_ITEM_KEY); if (ret) { *devid_ret = 1; } else { btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]); *devid_ret = found_key.offset + 1; } ret = 0; error: btrfs_free_path(path); return ret; } /* * the device information is stored in the chunk root * the btrfs_device struct should be fully filled in */ static int btrfs_add_dev_item(struct btrfs_trans_handle *trans, struct btrfs_device *device) { int ret; struct btrfs_path *path; struct btrfs_dev_item *dev_item; struct extent_buffer *leaf; struct btrfs_key key; unsigned long ptr; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.type = BTRFS_DEV_ITEM_KEY; key.offset = device->devid; btrfs_reserve_chunk_metadata(trans, true); ret = btrfs_insert_empty_item(trans, trans->fs_info->chunk_root, path, &key, sizeof(*dev_item)); btrfs_trans_release_chunk_metadata(trans); if (ret) goto out; leaf = path->nodes[0]; dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); btrfs_set_device_id(leaf, dev_item, device->devid); btrfs_set_device_generation(leaf, dev_item, 0); btrfs_set_device_type(leaf, dev_item, device->type); btrfs_set_device_io_align(leaf, dev_item, device->io_align); btrfs_set_device_io_width(leaf, dev_item, device->io_width); btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); btrfs_set_device_total_bytes(leaf, dev_item, btrfs_device_get_disk_total_bytes(device)); btrfs_set_device_bytes_used(leaf, dev_item, btrfs_device_get_bytes_used(device)); btrfs_set_device_group(leaf, dev_item, 0); btrfs_set_device_seek_speed(leaf, dev_item, 0); btrfs_set_device_bandwidth(leaf, dev_item, 0); btrfs_set_device_start_offset(leaf, dev_item, 0); ptr = btrfs_device_uuid(dev_item); write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); ptr = btrfs_device_fsid(dev_item); write_extent_buffer(leaf, trans->fs_info->fs_devices->metadata_uuid, ptr, BTRFS_FSID_SIZE); btrfs_mark_buffer_dirty(trans, leaf); ret = 0; out: btrfs_free_path(path); return ret; } /* * Function to update ctime/mtime for a given device path. * Mainly used for ctime/mtime based probe like libblkid. * * We don't care about errors here, this is just to be kind to userspace. */ static void update_dev_time(const char *device_path) { struct path path; int ret; ret = kern_path(device_path, LOOKUP_FOLLOW, &path); if (ret) return; inode_update_time(d_inode(path.dentry), S_MTIME | S_CTIME | S_VERSION); path_put(&path); } static int btrfs_rm_dev_item(struct btrfs_trans_handle *trans, struct btrfs_device *device) { struct btrfs_root *root = device->fs_info->chunk_root; int ret; struct btrfs_path *path; struct btrfs_key key; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.type = BTRFS_DEV_ITEM_KEY; key.offset = device->devid; btrfs_reserve_chunk_metadata(trans, false); ret = btrfs_search_slot(trans, root, &key, path, -1, 1); btrfs_trans_release_chunk_metadata(trans); if (ret) { if (ret > 0) ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, root, path); out: btrfs_free_path(path); return ret; } /* * Verify that @num_devices satisfies the RAID profile constraints in the whole * filesystem. It's up to the caller to adjust that number regarding eg. device * replace. */ static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info, u64 num_devices) { u64 all_avail; unsigned seq; int i; do { seq = read_seqbegin(&fs_info->profiles_lock); all_avail = fs_info->avail_data_alloc_bits | fs_info->avail_system_alloc_bits | fs_info->avail_metadata_alloc_bits; } while (read_seqretry(&fs_info->profiles_lock, seq)); for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { if (!(all_avail & btrfs_raid_array[i].bg_flag)) continue; if (num_devices < btrfs_raid_array[i].devs_min) return btrfs_raid_array[i].mindev_error; } return 0; } static struct btrfs_device * btrfs_find_next_active_device( struct btrfs_fs_devices *fs_devs, struct btrfs_device *device) { struct btrfs_device *next_device; list_for_each_entry(next_device, &fs_devs->devices, dev_list) { if (next_device != device && !test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state) && next_device->bdev) return next_device; } return NULL; } /* * Helper function to check if the given device is part of s_bdev / latest_dev * and replace it with the provided or the next active device, in the context * where this function called, there should be always be another device (or * this_dev) which is active. */ void __cold btrfs_assign_next_active_device(struct btrfs_device *device, struct btrfs_device *next_device) { struct btrfs_fs_info *fs_info = device->fs_info; if (!next_device) next_device = btrfs_find_next_active_device(fs_info->fs_devices, device); ASSERT(next_device); if (fs_info->sb->s_bdev && (fs_info->sb->s_bdev == device->bdev)) fs_info->sb->s_bdev = next_device->bdev; if (fs_info->fs_devices->latest_dev->bdev == device->bdev) fs_info->fs_devices->latest_dev = next_device; } /* * Return btrfs_fs_devices::num_devices excluding the device that's being * currently replaced. */ static u64 btrfs_num_devices(struct btrfs_fs_info *fs_info) { u64 num_devices = fs_info->fs_devices->num_devices; down_read(&fs_info->dev_replace.rwsem); if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { ASSERT(num_devices > 1); num_devices--; } up_read(&fs_info->dev_replace.rwsem); return num_devices; } static void btrfs_scratch_superblock(struct btrfs_fs_info *fs_info, struct block_device *bdev, int copy_num) { struct btrfs_super_block *disk_super; const size_t len = sizeof(disk_super->magic); const u64 bytenr = btrfs_sb_offset(copy_num); int ret; disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr); if (IS_ERR(disk_super)) return; memset(&disk_super->magic, 0, len); folio_mark_dirty(virt_to_folio(disk_super)); btrfs_release_disk_super(disk_super); ret = sync_blockdev_range(bdev, bytenr, bytenr + len - 1); if (ret) btrfs_warn(fs_info, "error clearing superblock number %d (%d)", copy_num, ret); } void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device) { int copy_num; struct block_device *bdev = device->bdev; if (!bdev) return; for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX; copy_num++) { if (bdev_is_zoned(bdev)) btrfs_reset_sb_log_zones(bdev, copy_num); else btrfs_scratch_superblock(fs_info, bdev, copy_num); } /* Notify udev that device has changed */ btrfs_kobject_uevent(bdev, KOBJ_CHANGE); /* Update ctime/mtime for device path for libblkid */ update_dev_time(device->name->str); } int btrfs_rm_device(struct btrfs_fs_info *fs_info, struct btrfs_dev_lookup_args *args, struct file **bdev_file) { struct btrfs_trans_handle *trans; struct btrfs_device *device; struct btrfs_fs_devices *cur_devices; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; u64 num_devices; int ret = 0; if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { btrfs_err(fs_info, "device remove not supported on extent tree v2 yet"); return -EINVAL; } /* * The device list in fs_devices is accessed without locks (neither * uuid_mutex nor device_list_mutex) as it won't change on a mounted * filesystem and another device rm cannot run. */ num_devices = btrfs_num_devices(fs_info); ret = btrfs_check_raid_min_devices(fs_info, num_devices - 1); if (ret) return ret; device = btrfs_find_device(fs_info->fs_devices, args); if (!device) { if (args->missing) ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND; else ret = -ENOENT; return ret; } if (btrfs_pinned_by_swapfile(fs_info, device)) { btrfs_warn_in_rcu(fs_info, "cannot remove device %s (devid %llu) due to active swapfile", btrfs_dev_name(device), device->devid); return -ETXTBSY; } if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) return BTRFS_ERROR_DEV_TGT_REPLACE; if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && fs_info->fs_devices->rw_devices == 1) return BTRFS_ERROR_DEV_ONLY_WRITABLE; if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { mutex_lock(&fs_info->chunk_mutex); list_del_init(&device->dev_alloc_list); device->fs_devices->rw_devices--; mutex_unlock(&fs_info->chunk_mutex); } ret = btrfs_shrink_device(device, 0); if (ret) goto error_undo; trans = btrfs_start_transaction(fs_info->chunk_root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto error_undo; } ret = btrfs_rm_dev_item(trans, device); if (ret) { /* Any error in dev item removal is critical */ btrfs_crit(fs_info, "failed to remove device item for devid %llu: %d", device->devid, ret); btrfs_abort_transaction(trans, ret); btrfs_end_transaction(trans); return ret; } clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); btrfs_scrub_cancel_dev(device); /* * the device list mutex makes sure that we don't change * the device list while someone else is writing out all * the device supers. Whoever is writing all supers, should * lock the device list mutex before getting the number of * devices in the super block (super_copy). Conversely, * whoever updates the number of devices in the super block * (super_copy) should hold the device list mutex. */ /* * In normal cases the cur_devices == fs_devices. But in case * of deleting a seed device, the cur_devices should point to * its own fs_devices listed under the fs_devices->seed_list. */ cur_devices = device->fs_devices; mutex_lock(&fs_devices->device_list_mutex); list_del_rcu(&device->dev_list); cur_devices->num_devices--; cur_devices->total_devices--; /* Update total_devices of the parent fs_devices if it's seed */ if (cur_devices != fs_devices) fs_devices->total_devices--; if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) cur_devices->missing_devices--; btrfs_assign_next_active_device(device, NULL); if (device->bdev_file) { cur_devices->open_devices--; /* remove sysfs entry */ btrfs_sysfs_remove_device(device); } num_devices = btrfs_super_num_devices(fs_info->super_copy) - 1; btrfs_set_super_num_devices(fs_info->super_copy, num_devices); mutex_unlock(&fs_devices->device_list_mutex); /* * At this point, the device is zero sized and detached from the * devices list. All that's left is to zero out the old supers and * free the device. * * We cannot call btrfs_close_bdev() here because we're holding the sb * write lock, and fput() on the block device will pull in the * ->open_mutex on the block device and it's dependencies. Instead * just flush the device and let the caller do the final bdev_release. */ if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { btrfs_scratch_superblocks(fs_info, device); if (device->bdev) { sync_blockdev(device->bdev); invalidate_bdev(device->bdev); } } *bdev_file = device->bdev_file; synchronize_rcu(); btrfs_free_device(device); /* * This can happen if cur_devices is the private seed devices list. We * cannot call close_fs_devices() here because it expects the uuid_mutex * to be held, but in fact we don't need that for the private * seed_devices, we can simply decrement cur_devices->opened and then * remove it from our list and free the fs_devices. */ if (cur_devices->num_devices == 0) { list_del_init(&cur_devices->seed_list); ASSERT(cur_devices->opened == 1); cur_devices->opened--; free_fs_devices(cur_devices); } ret = btrfs_commit_transaction(trans); return ret; error_undo: if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { mutex_lock(&fs_info->chunk_mutex); list_add(&device->dev_alloc_list, &fs_devices->alloc_list); device->fs_devices->rw_devices++; mutex_unlock(&fs_info->chunk_mutex); } return ret; } void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev) { struct btrfs_fs_devices *fs_devices; lockdep_assert_held(&srcdev->fs_info->fs_devices->device_list_mutex); /* * in case of fs with no seed, srcdev->fs_devices will point * to fs_devices of fs_info. However when the dev being replaced is * a seed dev it will point to the seed's local fs_devices. In short * srcdev will have its correct fs_devices in both the cases. */ fs_devices = srcdev->fs_devices; list_del_rcu(&srcdev->dev_list); list_del(&srcdev->dev_alloc_list); fs_devices->num_devices--; if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state)) fs_devices->missing_devices--; if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state)) fs_devices->rw_devices--; if (srcdev->bdev) fs_devices->open_devices--; } void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev) { struct btrfs_fs_devices *fs_devices = srcdev->fs_devices; mutex_lock(&uuid_mutex); btrfs_close_bdev(srcdev); synchronize_rcu(); btrfs_free_device(srcdev); /* if this is no devs we rather delete the fs_devices */ if (!fs_devices->num_devices) { /* * On a mounted FS, num_devices can't be zero unless it's a * seed. In case of a seed device being replaced, the replace * target added to the sprout FS, so there will be no more * device left under the seed FS. */ ASSERT(fs_devices->seeding); list_del_init(&fs_devices->seed_list); close_fs_devices(fs_devices); free_fs_devices(fs_devices); } mutex_unlock(&uuid_mutex); } void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev) { struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices; mutex_lock(&fs_devices->device_list_mutex); btrfs_sysfs_remove_device(tgtdev); if (tgtdev->bdev) fs_devices->open_devices--; fs_devices->num_devices--; btrfs_assign_next_active_device(tgtdev, NULL); list_del_rcu(&tgtdev->dev_list); mutex_unlock(&fs_devices->device_list_mutex); btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev); btrfs_close_bdev(tgtdev); synchronize_rcu(); btrfs_free_device(tgtdev); } /* * Populate args from device at path. * * @fs_info: the filesystem * @args: the args to populate * @path: the path to the device * * This will read the super block of the device at @path and populate @args with * the devid, fsid, and uuid. This is meant to be used for ioctls that need to * lookup a device to operate on, but need to do it before we take any locks. * This properly handles the special case of "missing" that a user may pass in, * and does some basic sanity checks. The caller must make sure that @path is * properly NUL terminated before calling in, and must call * btrfs_put_dev_args_from_path() in order to free up the temporary fsid and * uuid buffers. * * Return: 0 for success, -errno for failure */ int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info, struct btrfs_dev_lookup_args *args, const char *path) { struct btrfs_super_block *disk_super; struct file *bdev_file; int ret; if (!path || !path[0]) return -EINVAL; if (!strcmp(path, "missing")) { args->missing = true; return 0; } args->uuid = kzalloc(BTRFS_UUID_SIZE, GFP_KERNEL); args->fsid = kzalloc(BTRFS_FSID_SIZE, GFP_KERNEL); if (!args->uuid || !args->fsid) { btrfs_put_dev_args_from_path(args); return -ENOMEM; } ret = btrfs_get_bdev_and_sb(path, BLK_OPEN_READ, NULL, 0, &bdev_file, &disk_super); if (ret) { btrfs_put_dev_args_from_path(args); return ret; } args->devid = btrfs_stack_device_id(&disk_super->dev_item); memcpy(args->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE); if (btrfs_fs_incompat(fs_info, METADATA_UUID)) memcpy(args->fsid, disk_super->metadata_uuid, BTRFS_FSID_SIZE); else memcpy(args->fsid, disk_super->fsid, BTRFS_FSID_SIZE); btrfs_release_disk_super(disk_super); fput(bdev_file); return 0; } /* * Only use this jointly with btrfs_get_dev_args_from_path() because we will * allocate our ->uuid and ->fsid pointers, everybody else uses local variables * that don't need to be freed. */ void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args) { kfree(args->uuid); kfree(args->fsid); args->uuid = NULL; args->fsid = NULL; } struct btrfs_device *btrfs_find_device_by_devspec( struct btrfs_fs_info *fs_info, u64 devid, const char *device_path) { BTRFS_DEV_LOOKUP_ARGS(args); struct btrfs_device *device; int ret; if (devid) { args.devid = devid; device = btrfs_find_device(fs_info->fs_devices, &args); if (!device) return ERR_PTR(-ENOENT); return device; } ret = btrfs_get_dev_args_from_path(fs_info, &args, device_path); if (ret) return ERR_PTR(ret); device = btrfs_find_device(fs_info->fs_devices, &args); btrfs_put_dev_args_from_path(&args); if (!device) return ERR_PTR(-ENOENT); return device; } static struct btrfs_fs_devices *btrfs_init_sprout(struct btrfs_fs_info *fs_info) { struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; struct btrfs_fs_devices *old_devices; struct btrfs_fs_devices *seed_devices; lockdep_assert_held(&uuid_mutex); if (!fs_devices->seeding) return ERR_PTR(-EINVAL); /* * Private copy of the seed devices, anchored at * fs_info->fs_devices->seed_list */ seed_devices = alloc_fs_devices(NULL); if (IS_ERR(seed_devices)) return seed_devices; /* * It's necessary to retain a copy of the original seed fs_devices in * fs_uuids so that filesystems which have been seeded can successfully * reference the seed device from open_seed_devices. This also supports * multiple fs seed. */ old_devices = clone_fs_devices(fs_devices); if (IS_ERR(old_devices)) { kfree(seed_devices); return old_devices; } list_add(&old_devices->fs_list, &fs_uuids); memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); seed_devices->opened = 1; INIT_LIST_HEAD(&seed_devices->devices); INIT_LIST_HEAD(&seed_devices->alloc_list); mutex_init(&seed_devices->device_list_mutex); return seed_devices; } /* * Splice seed devices into the sprout fs_devices. * Generate a new fsid for the sprouted read-write filesystem. */ static void btrfs_setup_sprout(struct btrfs_fs_info *fs_info, struct btrfs_fs_devices *seed_devices) { struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; struct btrfs_super_block *disk_super = fs_info->super_copy; struct btrfs_device *device; u64 super_flags; /* * We are updating the fsid, the thread leading to device_list_add() * could race, so uuid_mutex is needed. */ lockdep_assert_held(&uuid_mutex); /* * The threads listed below may traverse dev_list but can do that without * device_list_mutex: * - All device ops and balance - as we are in btrfs_exclop_start. * - Various dev_list readers - are using RCU. * - btrfs_ioctl_fitrim() - is using RCU. * * For-read threads as below are using device_list_mutex: * - Readonly scrub btrfs_scrub_dev() * - Readonly scrub btrfs_scrub_progress() * - btrfs_get_dev_stats() */ lockdep_assert_held(&fs_devices->device_list_mutex); list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, synchronize_rcu); list_for_each_entry(device, &seed_devices->devices, dev_list) device->fs_devices = seed_devices; fs_devices->seeding = false; fs_devices->num_devices = 0; fs_devices->open_devices = 0; fs_devices->missing_devices = 0; fs_devices->rotating = false; list_add(&seed_devices->seed_list, &fs_devices->seed_list); generate_random_uuid(fs_devices->fsid); memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE); memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); super_flags = btrfs_super_flags(disk_super) & ~BTRFS_SUPER_FLAG_SEEDING; btrfs_set_super_flags(disk_super, super_flags); } /* * Store the expected generation for seed devices in device items. */ static int btrfs_finish_sprout(struct btrfs_trans_handle *trans) { BTRFS_DEV_LOOKUP_ARGS(args); struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *root = fs_info->chunk_root; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_dev_item *dev_item; struct btrfs_device *device; struct btrfs_key key; u8 fs_uuid[BTRFS_FSID_SIZE]; u8 dev_uuid[BTRFS_UUID_SIZE]; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.offset = 0; key.type = BTRFS_DEV_ITEM_KEY; while (1) { btrfs_reserve_chunk_metadata(trans, false); ret = btrfs_search_slot(trans, root, &key, path, 0, 1); btrfs_trans_release_chunk_metadata(trans); if (ret < 0) goto error; leaf = path->nodes[0]; next_slot: if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret > 0) break; if (ret < 0) goto error; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); btrfs_release_path(path); continue; } btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || key.type != BTRFS_DEV_ITEM_KEY) break; dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); args.devid = btrfs_device_id(leaf, dev_item); read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item), BTRFS_UUID_SIZE); read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item), BTRFS_FSID_SIZE); args.uuid = dev_uuid; args.fsid = fs_uuid; device = btrfs_find_device(fs_info->fs_devices, &args); BUG_ON(!device); /* Logic error */ if (device->fs_devices->seeding) { btrfs_set_device_generation(leaf, dev_item, device->generation); btrfs_mark_buffer_dirty(trans, leaf); } path->slots[0]++; goto next_slot; } ret = 0; error: btrfs_free_path(path); return ret; } int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path) { struct btrfs_root *root = fs_info->dev_root; struct btrfs_trans_handle *trans; struct btrfs_device *device; struct file *bdev_file; struct super_block *sb = fs_info->sb; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; struct btrfs_fs_devices *seed_devices = NULL; u64 orig_super_total_bytes; u64 orig_super_num_devices; int ret = 0; bool seeding_dev = false; bool locked = false; if (sb_rdonly(sb) && !fs_devices->seeding) return -EROFS; bdev_file = bdev_file_open_by_path(device_path, BLK_OPEN_WRITE, fs_info->bdev_holder, NULL); if (IS_ERR(bdev_file)) return PTR_ERR(bdev_file); if (!btrfs_check_device_zone_type(fs_info, file_bdev(bdev_file))) { ret = -EINVAL; goto error; } if (fs_devices->seeding) { seeding_dev = true; down_write(&sb->s_umount); mutex_lock(&uuid_mutex); locked = true; } sync_blockdev(file_bdev(bdev_file)); rcu_read_lock(); list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) { if (device->bdev == file_bdev(bdev_file)) { ret = -EEXIST; rcu_read_unlock(); goto error; } } rcu_read_unlock(); device = btrfs_alloc_device(fs_info, NULL, NULL, device_path); if (IS_ERR(device)) { /* we can safely leave the fs_devices entry around */ ret = PTR_ERR(device); goto error; } device->fs_info = fs_info; device->bdev_file = bdev_file; device->bdev = file_bdev(bdev_file); ret = lookup_bdev(device_path, &device->devt); if (ret) goto error_free_device; ret = btrfs_get_dev_zone_info(device, false); if (ret) goto error_free_device; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto error_free_zone; } set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); device->generation = trans->transid; device->io_width = fs_info->sectorsize; device->io_align = fs_info->sectorsize; device->sector_size = fs_info->sectorsize; device->total_bytes = round_down(bdev_nr_bytes(device->bdev), fs_info->sectorsize); device->disk_total_bytes = device->total_bytes; device->commit_total_bytes = device->total_bytes; set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); device->dev_stats_valid = 1; set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE); if (seeding_dev) { btrfs_clear_sb_rdonly(sb); /* GFP_KERNEL allocation must not be under device_list_mutex */ seed_devices = btrfs_init_sprout(fs_info); if (IS_ERR(seed_devices)) { ret = PTR_ERR(seed_devices); btrfs_abort_transaction(trans, ret); goto error_trans; } } mutex_lock(&fs_devices->device_list_mutex); if (seeding_dev) { btrfs_setup_sprout(fs_info, seed_devices); btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev, device); } device->fs_devices = fs_devices; mutex_lock(&fs_info->chunk_mutex); list_add_rcu(&device->dev_list, &fs_devices->devices); list_add(&device->dev_alloc_list, &fs_devices->alloc_list); fs_devices->num_devices++; fs_devices->open_devices++; fs_devices->rw_devices++; fs_devices->total_devices++; fs_devices->total_rw_bytes += device->total_bytes; atomic64_add(device->total_bytes, &fs_info->free_chunk_space); if (!bdev_nonrot(device->bdev)) fs_devices->rotating = true; orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy); btrfs_set_super_total_bytes(fs_info->super_copy, round_down(orig_super_total_bytes + device->total_bytes, fs_info->sectorsize)); orig_super_num_devices = btrfs_super_num_devices(fs_info->super_copy); btrfs_set_super_num_devices(fs_info->super_copy, orig_super_num_devices + 1); /* * we've got more storage, clear any full flags on the space * infos */ btrfs_clear_space_info_full(fs_info); mutex_unlock(&fs_info->chunk_mutex); /* Add sysfs device entry */ btrfs_sysfs_add_device(device); mutex_unlock(&fs_devices->device_list_mutex); if (seeding_dev) { mutex_lock(&fs_info->chunk_mutex); ret = init_first_rw_device(trans); mutex_unlock(&fs_info->chunk_mutex); if (ret) { btrfs_abort_transaction(trans, ret); goto error_sysfs; } } ret = btrfs_add_dev_item(trans, device); if (ret) { btrfs_abort_transaction(trans, ret); goto error_sysfs; } if (seeding_dev) { ret = btrfs_finish_sprout(trans); if (ret) { btrfs_abort_transaction(trans, ret); goto error_sysfs; } /* * fs_devices now represents the newly sprouted filesystem and * its fsid has been changed by btrfs_sprout_splice(). */ btrfs_sysfs_update_sprout_fsid(fs_devices); } ret = btrfs_commit_transaction(trans); if (seeding_dev) { mutex_unlock(&uuid_mutex); up_write(&sb->s_umount); locked = false; if (ret) /* transaction commit */ return ret; ret = btrfs_relocate_sys_chunks(fs_info); if (ret < 0) btrfs_handle_fs_error(fs_info, ret, "Failed to relocate sys chunks after device initialization. This can be fixed using the \"btrfs balance\" command."); trans = btrfs_attach_transaction(root); if (IS_ERR(trans)) { if (PTR_ERR(trans) == -ENOENT) return 0; ret = PTR_ERR(trans); trans = NULL; goto error_sysfs; } ret = btrfs_commit_transaction(trans); } /* * Now that we have written a new super block to this device, check all * other fs_devices list if device_path alienates any other scanned * device. * We can ignore the return value as it typically returns -EINVAL and * only succeeds if the device was an alien. */ btrfs_forget_devices(device->devt); /* Update ctime/mtime for blkid or udev */ update_dev_time(device_path); return ret; error_sysfs: btrfs_sysfs_remove_device(device); mutex_lock(&fs_info->fs_devices->device_list_mutex); mutex_lock(&fs_info->chunk_mutex); list_del_rcu(&device->dev_list); list_del(&device->dev_alloc_list); fs_info->fs_devices->num_devices--; fs_info->fs_devices->open_devices--; fs_info->fs_devices->rw_devices--; fs_info->fs_devices->total_devices--; fs_info->fs_devices->total_rw_bytes -= device->total_bytes; atomic64_sub(device->total_bytes, &fs_info->free_chunk_space); btrfs_set_super_total_bytes(fs_info->super_copy, orig_super_total_bytes); btrfs_set_super_num_devices(fs_info->super_copy, orig_super_num_devices); mutex_unlock(&fs_info->chunk_mutex); mutex_unlock(&fs_info->fs_devices->device_list_mutex); error_trans: if (seeding_dev) btrfs_set_sb_rdonly(sb); if (trans) btrfs_end_transaction(trans); error_free_zone: btrfs_destroy_dev_zone_info(device); error_free_device: btrfs_free_device(device); error: fput(bdev_file); if (locked) { mutex_unlock(&uuid_mutex); up_write(&sb->s_umount); } return ret; } static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, struct btrfs_device *device) { int ret; struct btrfs_path *path; struct btrfs_root *root = device->fs_info->chunk_root; struct btrfs_dev_item *dev_item; struct extent_buffer *leaf; struct btrfs_key key; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.type = BTRFS_DEV_ITEM_KEY; key.offset = device->devid; ret = btrfs_search_slot(trans, root, &key, path, 0, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } leaf = path->nodes[0]; dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); btrfs_set_device_id(leaf, dev_item, device->devid); btrfs_set_device_type(leaf, dev_item, device->type); btrfs_set_device_io_align(leaf, dev_item, device->io_align); btrfs_set_device_io_width(leaf, dev_item, device->io_width); btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); btrfs_set_device_total_bytes(leaf, dev_item, btrfs_device_get_disk_total_bytes(device)); btrfs_set_device_bytes_used(leaf, dev_item, btrfs_device_get_bytes_used(device)); btrfs_mark_buffer_dirty(trans, leaf); out: btrfs_free_path(path); return ret; } int btrfs_grow_device(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 new_size) { struct btrfs_fs_info *fs_info = device->fs_info; struct btrfs_super_block *super_copy = fs_info->super_copy; u64 old_total; u64 diff; int ret; if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) return -EACCES; new_size = round_down(new_size, fs_info->sectorsize); mutex_lock(&fs_info->chunk_mutex); old_total = btrfs_super_total_bytes(super_copy); diff = round_down(new_size - device->total_bytes, fs_info->sectorsize); if (new_size <= device->total_bytes || test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { mutex_unlock(&fs_info->chunk_mutex); return -EINVAL; } btrfs_set_super_total_bytes(super_copy, round_down(old_total + diff, fs_info->sectorsize)); device->fs_devices->total_rw_bytes += diff; atomic64_add(diff, &fs_info->free_chunk_space); btrfs_device_set_total_bytes(device, new_size); btrfs_device_set_disk_total_bytes(device, new_size); btrfs_clear_space_info_full(device->fs_info); if (list_empty(&device->post_commit_list)) list_add_tail(&device->post_commit_list, &trans->transaction->dev_update_list); mutex_unlock(&fs_info->chunk_mutex); btrfs_reserve_chunk_metadata(trans, false); ret = btrfs_update_device(trans, device); btrfs_trans_release_chunk_metadata(trans); return ret; } static int btrfs_free_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *root = fs_info->chunk_root; int ret; struct btrfs_path *path; struct btrfs_key key; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = chunk_offset; key.type = BTRFS_CHUNK_ITEM_KEY; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; else if (ret > 0) { /* Logic error or corruption */ btrfs_handle_fs_error(fs_info, -ENOENT, "Failed lookup while freeing chunk."); ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, root, path); if (ret < 0) btrfs_handle_fs_error(fs_info, ret, "Failed to delete chunk item."); out: btrfs_free_path(path); return ret; } static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset) { struct btrfs_super_block *super_copy = fs_info->super_copy; struct btrfs_disk_key *disk_key; struct btrfs_chunk *chunk; u8 *ptr; int ret = 0; u32 num_stripes; u32 array_size; u32 len = 0; u32 cur; struct btrfs_key key; lockdep_assert_held(&fs_info->chunk_mutex); array_size = btrfs_super_sys_array_size(super_copy); ptr = super_copy->sys_chunk_array; cur = 0; while (cur < array_size) { disk_key = (struct btrfs_disk_key *)ptr; btrfs_disk_key_to_cpu(&key, disk_key); len = sizeof(*disk_key); if (key.type == BTRFS_CHUNK_ITEM_KEY) { chunk = (struct btrfs_chunk *)(ptr + len); num_stripes = btrfs_stack_chunk_num_stripes(chunk); len += btrfs_chunk_item_size(num_stripes); } else { ret = -EIO; break; } if (key.objectid == BTRFS_FIRST_CHUNK_TREE_OBJECTID && key.offset == chunk_offset) { memmove(ptr, ptr + len, array_size - (cur + len)); array_size -= len; btrfs_set_super_sys_array_size(super_copy, array_size); } else { ptr += len; cur += len; } } return ret; } struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info, u64 logical, u64 length) { struct rb_node *node = fs_info->mapping_tree.rb_root.rb_node; struct rb_node *prev = NULL; struct rb_node *orig_prev; struct btrfs_chunk_map *map; struct btrfs_chunk_map *prev_map = NULL; while (node) { map = rb_entry(node, struct btrfs_chunk_map, rb_node); prev = node; prev_map = map; if (logical < map->start) { node = node->rb_left; } else if (logical >= map->start + map->chunk_len) { node = node->rb_right; } else { refcount_inc(&map->refs); return map; } } if (!prev) return NULL; orig_prev = prev; while (prev && logical >= prev_map->start + prev_map->chunk_len) { prev = rb_next(prev); prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node); } if (!prev) { prev = orig_prev; prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node); while (prev && logical < prev_map->start) { prev = rb_prev(prev); prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node); } } if (prev) { u64 end = logical + length; /* * Caller can pass a U64_MAX length when it wants to get any * chunk starting at an offset of 'logical' or higher, so deal * with underflow by resetting the end offset to U64_MAX. */ if (end < logical) end = U64_MAX; if (end > prev_map->start && logical < prev_map->start + prev_map->chunk_len) { refcount_inc(&prev_map->refs); return prev_map; } } return NULL; } struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info, u64 logical, u64 length) { struct btrfs_chunk_map *map; read_lock(&fs_info->mapping_tree_lock); map = btrfs_find_chunk_map_nolock(fs_info, logical, length); read_unlock(&fs_info->mapping_tree_lock); return map; } /* * Find the mapping containing the given logical extent. * * @logical: Logical block offset in bytes. * @length: Length of extent in bytes. * * Return: Chunk mapping or ERR_PTR. */ struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info, u64 logical, u64 length) { struct btrfs_chunk_map *map; map = btrfs_find_chunk_map(fs_info, logical, length); if (unlikely(!map)) { btrfs_crit(fs_info, "unable to find chunk map for logical %llu length %llu", logical, length); return ERR_PTR(-EINVAL); } if (unlikely(map->start > logical || map->start + map->chunk_len <= logical)) { btrfs_crit(fs_info, "found a bad chunk map, wanted %llu-%llu, found %llu-%llu", logical, logical + length, map->start, map->start + map->chunk_len); btrfs_free_chunk_map(map); return ERR_PTR(-EINVAL); } /* Callers are responsible for dropping the reference. */ return map; } static int remove_chunk_item(struct btrfs_trans_handle *trans, struct btrfs_chunk_map *map, u64 chunk_offset) { int i; /* * Removing chunk items and updating the device items in the chunks btree * requires holding the chunk_mutex. * See the comment at btrfs_chunk_alloc() for the details. */ lockdep_assert_held(&trans->fs_info->chunk_mutex); for (i = 0; i < map->num_stripes; i++) { int ret; ret = btrfs_update_device(trans, map->stripes[i].dev); if (ret) return ret; } return btrfs_free_chunk(trans, chunk_offset); } int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_chunk_map *map; u64 dev_extent_len = 0; int i, ret = 0; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; map = btrfs_get_chunk_map(fs_info, chunk_offset, 1); if (IS_ERR(map)) { /* * This is a logic error, but we don't want to just rely on the * user having built with ASSERT enabled, so if ASSERT doesn't * do anything we still error out. */ ASSERT(0); return PTR_ERR(map); } /* * First delete the device extent items from the devices btree. * We take the device_list_mutex to avoid racing with the finishing phase * of a device replace operation. See the comment below before acquiring * fs_info->chunk_mutex. Note that here we do not acquire the chunk_mutex * because that can result in a deadlock when deleting the device extent * items from the devices btree - COWing an extent buffer from the btree * may result in allocating a new metadata chunk, which would attempt to * lock again fs_info->chunk_mutex. */ mutex_lock(&fs_devices->device_list_mutex); for (i = 0; i < map->num_stripes; i++) { struct btrfs_device *device = map->stripes[i].dev; ret = btrfs_free_dev_extent(trans, device, map->stripes[i].physical, &dev_extent_len); if (ret) { mutex_unlock(&fs_devices->device_list_mutex); btrfs_abort_transaction(trans, ret); goto out; } if (device->bytes_used > 0) { mutex_lock(&fs_info->chunk_mutex); btrfs_device_set_bytes_used(device, device->bytes_used - dev_extent_len); atomic64_add(dev_extent_len, &fs_info->free_chunk_space); btrfs_clear_space_info_full(fs_info); mutex_unlock(&fs_info->chunk_mutex); } } mutex_unlock(&fs_devices->device_list_mutex); /* * We acquire fs_info->chunk_mutex for 2 reasons: * * 1) Just like with the first phase of the chunk allocation, we must * reserve system space, do all chunk btree updates and deletions, and * update the system chunk array in the superblock while holding this * mutex. This is for similar reasons as explained on the comment at * the top of btrfs_chunk_alloc(); * * 2) Prevent races with the final phase of a device replace operation * that replaces the device object associated with the map's stripes, * because the device object's id can change at any time during that * final phase of the device replace operation * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the * replaced device and then see it with an ID of * BTRFS_DEV_REPLACE_DEVID, which would cause a failure when updating * the device item, which does not exists on the chunk btree. * The finishing phase of device replace acquires both the * device_list_mutex and the chunk_mutex, in that order, so we are * safe by just acquiring the chunk_mutex. */ trans->removing_chunk = true; mutex_lock(&fs_info->chunk_mutex); check_system_chunk(trans, map->type); ret = remove_chunk_item(trans, map, chunk_offset); /* * Normally we should not get -ENOSPC since we reserved space before * through the call to check_system_chunk(). * * Despite our system space_info having enough free space, we may not * be able to allocate extents from its block groups, because all have * an incompatible profile, which will force us to allocate a new system * block group with the right profile, or right after we called * check_system_space() above, a scrub turned the only system block group * with enough free space into RO mode. * This is explained with more detail at do_chunk_alloc(). * * So if we get -ENOSPC, allocate a new system chunk and retry once. */ if (ret == -ENOSPC) { const u64 sys_flags = btrfs_system_alloc_profile(fs_info); struct btrfs_block_group *sys_bg; sys_bg = btrfs_create_chunk(trans, sys_flags); if (IS_ERR(sys_bg)) { ret = PTR_ERR(sys_bg); btrfs_abort_transaction(trans, ret); goto out; } ret = btrfs_chunk_alloc_add_chunk_item(trans, sys_bg); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } ret = remove_chunk_item(trans, map, chunk_offset); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } } else if (ret) { btrfs_abort_transaction(trans, ret); goto out; } trace_btrfs_chunk_free(fs_info, map, chunk_offset, map->chunk_len); if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { ret = btrfs_del_sys_chunk(fs_info, chunk_offset); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } } mutex_unlock(&fs_info->chunk_mutex); trans->removing_chunk = false; /* * We are done with chunk btree updates and deletions, so release the * system space we previously reserved (with check_system_chunk()). */ btrfs_trans_release_chunk_metadata(trans); ret = btrfs_remove_block_group(trans, map); if (ret) { btrfs_abort_transaction(trans, ret); goto out; } out: if (trans->removing_chunk) { mutex_unlock(&fs_info->chunk_mutex); trans->removing_chunk = false; } /* once for us */ btrfs_free_chunk_map(map); return ret; } int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset) { struct btrfs_root *root = fs_info->chunk_root; struct btrfs_trans_handle *trans; struct btrfs_block_group *block_group; u64 length; int ret; if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { btrfs_err(fs_info, "relocate: not supported on extent tree v2 yet"); return -EINVAL; } /* * Prevent races with automatic removal of unused block groups. * After we relocate and before we remove the chunk with offset * chunk_offset, automatic removal of the block group can kick in, * resulting in a failure when calling btrfs_remove_chunk() below. * * Make sure to acquire this mutex before doing a tree search (dev * or chunk trees) to find chunks. Otherwise the cleaner kthread might * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after * we release the path used to search the chunk/dev tree and before * the current task acquires this mutex and calls us. */ lockdep_assert_held(&fs_info->reclaim_bgs_lock); /* step one, relocate all the extents inside this chunk */ btrfs_scrub_pause(fs_info); ret = btrfs_relocate_block_group(fs_info, chunk_offset); btrfs_scrub_continue(fs_info); if (ret) { /* * If we had a transaction abort, stop all running scrubs. * See transaction.c:cleanup_transaction() why we do it here. */ if (BTRFS_FS_ERROR(fs_info)) btrfs_scrub_cancel(fs_info); return ret; } block_group = btrfs_lookup_block_group(fs_info, chunk_offset); if (!block_group) return -ENOENT; btrfs_discard_cancel_work(&fs_info->discard_ctl, block_group); length = block_group->length; btrfs_put_block_group(block_group); /* * On a zoned file system, discard the whole block group, this will * trigger a REQ_OP_ZONE_RESET operation on the device zone. If * resetting the zone fails, don't treat it as a fatal problem from the * filesystem's point of view. */ if (btrfs_is_zoned(fs_info)) { ret = btrfs_discard_extent(fs_info, chunk_offset, length, NULL); if (ret) btrfs_info(fs_info, "failed to reset zone %llu after relocation", chunk_offset); } trans = btrfs_start_trans_remove_block_group(root->fs_info, chunk_offset); if (IS_ERR(trans)) { ret = PTR_ERR(trans); btrfs_handle_fs_error(root->fs_info, ret, NULL); return ret; } /* * step two, delete the device extents and the * chunk tree entries */ ret = btrfs_remove_chunk(trans, chunk_offset); btrfs_end_transaction(trans); return ret; } static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info) { struct btrfs_root *chunk_root = fs_info->chunk_root; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_chunk *chunk; struct btrfs_key key; struct btrfs_key found_key; u64 chunk_type; bool retried = false; int failed = 0; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; again: key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; while (1) { mutex_lock(&fs_info->reclaim_bgs_lock); ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); if (ret < 0) { mutex_unlock(&fs_info->reclaim_bgs_lock); goto error; } if (ret == 0) { /* * On the first search we would find chunk tree with * offset -1, which is not possible. On subsequent * loops this would find an existing item on an invalid * offset (one less than the previous one, wrong * alignment and size). */ ret = -EUCLEAN; goto error; } ret = btrfs_previous_item(chunk_root, path, key.objectid, key.type); if (ret) mutex_unlock(&fs_info->reclaim_bgs_lock); if (ret < 0) goto error; if (ret > 0) break; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); chunk = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_chunk); chunk_type = btrfs_chunk_type(leaf, chunk); btrfs_release_path(path); if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { ret = btrfs_relocate_chunk(fs_info, found_key.offset); if (ret == -ENOSPC) failed++; else BUG_ON(ret); } mutex_unlock(&fs_info->reclaim_bgs_lock); if (found_key.offset == 0) break; key.offset = found_key.offset - 1; } ret = 0; if (failed && !retried) { failed = 0; retried = true; goto again; } else if (WARN_ON(failed && retried)) { ret = -ENOSPC; } error: btrfs_free_path(path); return ret; } /* * return 1 : allocate a data chunk successfully, * return <0: errors during allocating a data chunk, * return 0 : no need to allocate a data chunk. */ static int btrfs_may_alloc_data_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset) { struct btrfs_block_group *cache; u64 bytes_used; u64 chunk_type; cache = btrfs_lookup_block_group(fs_info, chunk_offset); ASSERT(cache); chunk_type = cache->flags; btrfs_put_block_group(cache); if (!(chunk_type & BTRFS_BLOCK_GROUP_DATA)) return 0; spin_lock(&fs_info->data_sinfo->lock); bytes_used = fs_info->data_sinfo->bytes_used; spin_unlock(&fs_info->data_sinfo->lock); if (!bytes_used) { struct btrfs_trans_handle *trans; int ret; trans = btrfs_join_transaction(fs_info->tree_root); if (IS_ERR(trans)) return PTR_ERR(trans); ret = btrfs_force_chunk_alloc(trans, BTRFS_BLOCK_GROUP_DATA); btrfs_end_transaction(trans); if (ret < 0) return ret; return 1; } return 0; } static void btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args *cpu, const struct btrfs_disk_balance_args *disk) { memset(cpu, 0, sizeof(*cpu)); cpu->profiles = le64_to_cpu(disk->profiles); cpu->usage = le64_to_cpu(disk->usage); cpu->devid = le64_to_cpu(disk->devid); cpu->pstart = le64_to_cpu(disk->pstart); cpu->pend = le64_to_cpu(disk->pend); cpu->vstart = le64_to_cpu(disk->vstart); cpu->vend = le64_to_cpu(disk->vend); cpu->target = le64_to_cpu(disk->target); cpu->flags = le64_to_cpu(disk->flags); cpu->limit = le64_to_cpu(disk->limit); cpu->stripes_min = le32_to_cpu(disk->stripes_min); cpu->stripes_max = le32_to_cpu(disk->stripes_max); } static void btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args *disk, const struct btrfs_balance_args *cpu) { memset(disk, 0, sizeof(*disk)); disk->profiles = cpu_to_le64(cpu->profiles); disk->usage = cpu_to_le64(cpu->usage); disk->devid = cpu_to_le64(cpu->devid); disk->pstart = cpu_to_le64(cpu->pstart); disk->pend = cpu_to_le64(cpu->pend); disk->vstart = cpu_to_le64(cpu->vstart); disk->vend = cpu_to_le64(cpu->vend); disk->target = cpu_to_le64(cpu->target); disk->flags = cpu_to_le64(cpu->flags); disk->limit = cpu_to_le64(cpu->limit); disk->stripes_min = cpu_to_le32(cpu->stripes_min); disk->stripes_max = cpu_to_le32(cpu->stripes_max); } static int insert_balance_item(struct btrfs_fs_info *fs_info, struct btrfs_balance_control *bctl) { struct btrfs_root *root = fs_info->tree_root; struct btrfs_trans_handle *trans; struct btrfs_balance_item *item; struct btrfs_disk_balance_args disk_bargs; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key; int ret, err; path = btrfs_alloc_path(); if (!path) return -ENOMEM; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } key.objectid = BTRFS_BALANCE_OBJECTID; key.type = BTRFS_TEMPORARY_ITEM_KEY; key.offset = 0; ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*item)); if (ret) goto out; leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item)); btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); btrfs_set_balance_data(leaf, item, &disk_bargs); btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); btrfs_set_balance_meta(leaf, item, &disk_bargs); btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); btrfs_set_balance_sys(leaf, item, &disk_bargs); btrfs_set_balance_flags(leaf, item, bctl->flags); btrfs_mark_buffer_dirty(trans, leaf); out: btrfs_free_path(path); err = btrfs_commit_transaction(trans); if (err && !ret) ret = err; return ret; } static int del_balance_item(struct btrfs_fs_info *fs_info) { struct btrfs_root *root = fs_info->tree_root; struct btrfs_trans_handle *trans; struct btrfs_path *path; struct btrfs_key key; int ret, err; path = btrfs_alloc_path(); if (!path) return -ENOMEM; trans = btrfs_start_transaction_fallback_global_rsv(root, 0); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } key.objectid = BTRFS_BALANCE_OBJECTID; key.type = BTRFS_TEMPORARY_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0) { ret = -ENOENT; goto out; } ret = btrfs_del_item(trans, root, path); out: btrfs_free_path(path); err = btrfs_commit_transaction(trans); if (err && !ret) ret = err; return ret; } /* * This is a heuristic used to reduce the number of chunks balanced on * resume after balance was interrupted. */ static void update_balance_args(struct btrfs_balance_control *bctl) { /* * Turn on soft mode for chunk types that were being converted. */ if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; /* * Turn on usage filter if is not already used. The idea is * that chunks that we have already balanced should be * reasonably full. Don't do it for chunks that are being * converted - that will keep us from relocating unconverted * (albeit full) chunks. */ if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; bctl->data.usage = 90; } if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; bctl->sys.usage = 90; } if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; bctl->meta.usage = 90; } } /* * Clear the balance status in fs_info and delete the balance item from disk. */ static void reset_balance_state(struct btrfs_fs_info *fs_info) { struct btrfs_balance_control *bctl = fs_info->balance_ctl; int ret; ASSERT(fs_info->balance_ctl); spin_lock(&fs_info->balance_lock); fs_info->balance_ctl = NULL; spin_unlock(&fs_info->balance_lock); kfree(bctl); ret = del_balance_item(fs_info); if (ret) btrfs_handle_fs_error(fs_info, ret, NULL); } /* * Balance filters. Return 1 if chunk should be filtered out * (should not be balanced). */ static int chunk_profiles_filter(u64 chunk_type, struct btrfs_balance_args *bargs) { chunk_type = chunk_to_extended(chunk_type) & BTRFS_EXTENDED_PROFILE_MASK; if (bargs->profiles & chunk_type) return 0; return 1; } static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, struct btrfs_balance_args *bargs) { struct btrfs_block_group *cache; u64 chunk_used; u64 user_thresh_min; u64 user_thresh_max; int ret = 1; cache = btrfs_lookup_block_group(fs_info, chunk_offset); chunk_used = cache->used; if (bargs->usage_min == 0) user_thresh_min = 0; else user_thresh_min = mult_perc(cache->length, bargs->usage_min); if (bargs->usage_max == 0) user_thresh_max = 1; else if (bargs->usage_max > 100) user_thresh_max = cache->length; else user_thresh_max = mult_perc(cache->length, bargs->usage_max); if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max) ret = 0; btrfs_put_block_group(cache); return ret; } static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, struct btrfs_balance_args *bargs) { struct btrfs_block_group *cache; u64 chunk_used, user_thresh; int ret = 1; cache = btrfs_lookup_block_group(fs_info, chunk_offset); chunk_used = cache->used; if (bargs->usage_min == 0) user_thresh = 1; else if (bargs->usage > 100) user_thresh = cache->length; else user_thresh = mult_perc(cache->length, bargs->usage); if (chunk_used < user_thresh) ret = 0; btrfs_put_block_group(cache); return ret; } static int chunk_devid_filter(struct extent_buffer *leaf, struct btrfs_chunk *chunk, struct btrfs_balance_args *bargs) { struct btrfs_stripe *stripe; int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); int i; for (i = 0; i < num_stripes; i++) { stripe = btrfs_stripe_nr(chunk, i); if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) return 0; } return 1; } static u64 calc_data_stripes(u64 type, int num_stripes) { const int index = btrfs_bg_flags_to_raid_index(type); const int ncopies = btrfs_raid_array[index].ncopies; const int nparity = btrfs_raid_array[index].nparity; return (num_stripes - nparity) / ncopies; } /* [pstart, pend) */ static int chunk_drange_filter(struct extent_buffer *leaf, struct btrfs_chunk *chunk, struct btrfs_balance_args *bargs) { struct btrfs_stripe *stripe; int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); u64 stripe_offset; u64 stripe_length; u64 type; int factor; int i; if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) return 0; type = btrfs_chunk_type(leaf, chunk); factor = calc_data_stripes(type, num_stripes); for (i = 0; i < num_stripes; i++) { stripe = btrfs_stripe_nr(chunk, i); if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) continue; stripe_offset = btrfs_stripe_offset(leaf, stripe); stripe_length = btrfs_chunk_length(leaf, chunk); stripe_length = div_u64(stripe_length, factor); if (stripe_offset < bargs->pend && stripe_offset + stripe_length > bargs->pstart) return 0; } return 1; } /* [vstart, vend) */ static int chunk_vrange_filter(struct extent_buffer *leaf, struct btrfs_chunk *chunk, u64 chunk_offset, struct btrfs_balance_args *bargs) { if (chunk_offset < bargs->vend && chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) /* at least part of the chunk is inside this vrange */ return 0; return 1; } static int chunk_stripes_range_filter(struct extent_buffer *leaf, struct btrfs_chunk *chunk, struct btrfs_balance_args *bargs) { int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); if (bargs->stripes_min <= num_stripes && num_stripes <= bargs->stripes_max) return 0; return 1; } static int chunk_soft_convert_filter(u64 chunk_type, struct btrfs_balance_args *bargs) { if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) return 0; chunk_type = chunk_to_extended(chunk_type) & BTRFS_EXTENDED_PROFILE_MASK; if (bargs->target == chunk_type) return 1; return 0; } static int should_balance_chunk(struct extent_buffer *leaf, struct btrfs_chunk *chunk, u64 chunk_offset) { struct btrfs_fs_info *fs_info = leaf->fs_info; struct btrfs_balance_control *bctl = fs_info->balance_ctl; struct btrfs_balance_args *bargs = NULL; u64 chunk_type = btrfs_chunk_type(leaf, chunk); /* type filter */ if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { return 0; } if (chunk_type & BTRFS_BLOCK_GROUP_DATA) bargs = &bctl->data; else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) bargs = &bctl->sys; else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) bargs = &bctl->meta; /* profiles filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && chunk_profiles_filter(chunk_type, bargs)) { return 0; } /* usage filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && chunk_usage_filter(fs_info, chunk_offset, bargs)) { return 0; } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && chunk_usage_range_filter(fs_info, chunk_offset, bargs)) { return 0; } /* devid filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && chunk_devid_filter(leaf, chunk, bargs)) { return 0; } /* drange filter, makes sense only with devid filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && chunk_drange_filter(leaf, chunk, bargs)) { return 0; } /* vrange filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { return 0; } /* stripes filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) && chunk_stripes_range_filter(leaf, chunk, bargs)) { return 0; } /* soft profile changing mode */ if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && chunk_soft_convert_filter(chunk_type, bargs)) { return 0; } /* * limited by count, must be the last filter */ if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) { if (bargs->limit == 0) return 0; else bargs->limit--; } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) { /* * Same logic as the 'limit' filter; the minimum cannot be * determined here because we do not have the global information * about the count of all chunks that satisfy the filters. */ if (bargs->limit_max == 0) return 0; else bargs->limit_max--; } return 1; } static int __btrfs_balance(struct btrfs_fs_info *fs_info) { struct btrfs_balance_control *bctl = fs_info->balance_ctl; struct btrfs_root *chunk_root = fs_info->chunk_root; u64 chunk_type; struct btrfs_chunk *chunk; struct btrfs_path *path = NULL; struct btrfs_key key; struct btrfs_key found_key; struct extent_buffer *leaf; int slot; int ret; int enospc_errors = 0; bool counting = true; /* The single value limit and min/max limits use the same bytes in the */ u64 limit_data = bctl->data.limit; u64 limit_meta = bctl->meta.limit; u64 limit_sys = bctl->sys.limit; u32 count_data = 0; u32 count_meta = 0; u32 count_sys = 0; int chunk_reserved = 0; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto error; } /* zero out stat counters */ spin_lock(&fs_info->balance_lock); memset(&bctl->stat, 0, sizeof(bctl->stat)); spin_unlock(&fs_info->balance_lock); again: if (!counting) { /* * The single value limit and min/max limits use the same bytes * in the */ bctl->data.limit = limit_data; bctl->meta.limit = limit_meta; bctl->sys.limit = limit_sys; } key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; while (1) { if ((!counting && atomic_read(&fs_info->balance_pause_req)) || atomic_read(&fs_info->balance_cancel_req)) { ret = -ECANCELED; goto error; } mutex_lock(&fs_info->reclaim_bgs_lock); ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); if (ret < 0) { mutex_unlock(&fs_info->reclaim_bgs_lock); goto error; } /* * this shouldn't happen, it means the last relocate * failed */ if (ret == 0) BUG(); /* FIXME break ? */ ret = btrfs_previous_item(chunk_root, path, 0, BTRFS_CHUNK_ITEM_KEY); if (ret) { mutex_unlock(&fs_info->reclaim_bgs_lock); ret = 0; break; } leaf = path->nodes[0]; slot = path->slots[0]; btrfs_item_key_to_cpu(leaf, &found_key, slot); if (found_key.objectid != key.objectid) { mutex_unlock(&fs_info->reclaim_bgs_lock); break; } chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); chunk_type = btrfs_chunk_type(leaf, chunk); if (!counting) { spin_lock(&fs_info->balance_lock); bctl->stat.considered++; spin_unlock(&fs_info->balance_lock); } ret = should_balance_chunk(leaf, chunk, found_key.offset); btrfs_release_path(path); if (!ret) { mutex_unlock(&fs_info->reclaim_bgs_lock); goto loop; } if (counting) { mutex_unlock(&fs_info->reclaim_bgs_lock); spin_lock(&fs_info->balance_lock); bctl->stat.expected++; spin_unlock(&fs_info->balance_lock); if (chunk_type & BTRFS_BLOCK_GROUP_DATA) count_data++; else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) count_sys++; else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) count_meta++; goto loop; } /* * Apply limit_min filter, no need to check if the LIMITS * filter is used, limit_min is 0 by default */ if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) && count_data < bctl->data.limit_min) || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) && count_meta < bctl->meta.limit_min) || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) && count_sys < bctl->sys.limit_min)) { mutex_unlock(&fs_info->reclaim_bgs_lock); goto loop; } if (!chunk_reserved) { /* * We may be relocating the only data chunk we have, * which could potentially end up with losing data's * raid profile, so lets allocate an empty one in * advance. */ ret = btrfs_may_alloc_data_chunk(fs_info, found_key.offset); if (ret < 0) { mutex_unlock(&fs_info->reclaim_bgs_lock); goto error; } else if (ret == 1) { chunk_reserved = 1; } } ret = btrfs_relocate_chunk(fs_info, found_key.offset); mutex_unlock(&fs_info->reclaim_bgs_lock); if (ret == -ENOSPC) { enospc_errors++; } else if (ret == -ETXTBSY) { btrfs_info(fs_info, "skipping relocation of block group %llu due to active swapfile", found_key.offset); ret = 0; } else if (ret) { goto error; } else { spin_lock(&fs_info->balance_lock); bctl->stat.completed++; spin_unlock(&fs_info->balance_lock); } loop: if (found_key.offset == 0) break; key.offset = found_key.offset - 1; } if (counting) { btrfs_release_path(path); counting = false; goto again; } error: btrfs_free_path(path); if (enospc_errors) { btrfs_info(fs_info, "%d enospc errors during balance", enospc_errors); if (!ret) ret = -ENOSPC; } return ret; } /* * See if a given profile is valid and reduced. * * @flags: profile to validate * @extended: if true @flags is treated as an extended profile */ static int alloc_profile_is_valid(u64 flags, int extended) { u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : BTRFS_BLOCK_GROUP_PROFILE_MASK); flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; /* 1) check that all other bits are zeroed */ if (flags & ~mask) return 0; /* 2) see if profile is reduced */ if (flags == 0) return !extended; /* "0" is valid for usual profiles */ return has_single_bit_set(flags); } /* * Validate target profile against allowed profiles and return true if it's OK. * Otherwise print the error message and return false. */ static inline int validate_convert_profile(struct btrfs_fs_info *fs_info, const struct btrfs_balance_args *bargs, u64 allowed, const char *type) { if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) return true; /* Profile is valid and does not have bits outside of the allowed set */ if (alloc_profile_is_valid(bargs->target, 1) && (bargs->target & ~allowed) == 0) return true; btrfs_err(fs_info, "balance: invalid convert %s profile %s", type, btrfs_bg_type_to_raid_name(bargs->target)); return false; } /* * Fill @buf with textual description of balance filter flags @bargs, up to * @size_buf including the terminating null. The output may be trimmed if it * does not fit into the provided buffer. */ static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf, u32 size_buf) { int ret; u32 size_bp = size_buf; char *bp = buf; u64 flags = bargs->flags; char tmp_buf[128] = {'\0'}; if (!flags) return; #define CHECK_APPEND_NOARG(a) \ do { \ ret = snprintf(bp, size_bp, (a)); \ if (ret < 0 || ret >= size_bp) \ goto out_overflow; \ size_bp -= ret; \ bp += ret; \ } while (0) #define CHECK_APPEND_1ARG(a, v1) \ do { \ ret = snprintf(bp, size_bp, (a), (v1)); \ if (ret < 0 || ret >= size_bp) \ goto out_overflow; \ size_bp -= ret; \ bp += ret; \ } while (0) #define CHECK_APPEND_2ARG(a, v1, v2) \ do { \ ret = snprintf(bp, size_bp, (a), (v1), (v2)); \ if (ret < 0 || ret >= size_bp) \ goto out_overflow; \ size_bp -= ret; \ bp += ret; \ } while (0) if (flags & BTRFS_BALANCE_ARGS_CONVERT) CHECK_APPEND_1ARG("convert=%s,", btrfs_bg_type_to_raid_name(bargs->target)); if (flags & BTRFS_BALANCE_ARGS_SOFT) CHECK_APPEND_NOARG("soft,"); if (flags & BTRFS_BALANCE_ARGS_PROFILES) { btrfs_describe_block_groups(bargs->profiles, tmp_buf, sizeof(tmp_buf)); CHECK_APPEND_1ARG("profiles=%s,", tmp_buf); } if (flags & BTRFS_BALANCE_ARGS_USAGE) CHECK_APPEND_1ARG("usage=%llu,", bargs->usage); if (flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) CHECK_APPEND_2ARG("usage=%u..%u,", bargs->usage_min, bargs->usage_max); if (flags & BTRFS_BALANCE_ARGS_DEVID) CHECK_APPEND_1ARG("devid=%llu,", bargs->devid); if (flags & BTRFS_BALANCE_ARGS_DRANGE) CHECK_APPEND_2ARG("drange=%llu..%llu,", bargs->pstart, bargs->pend); if (flags & BTRFS_BALANCE_ARGS_VRANGE) CHECK_APPEND_2ARG("vrange=%llu..%llu,", bargs->vstart, bargs->vend); if (flags & BTRFS_BALANCE_ARGS_LIMIT) CHECK_APPEND_1ARG("limit=%llu,", bargs->limit); if (flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE) CHECK_APPEND_2ARG("limit=%u..%u,", bargs->limit_min, bargs->limit_max); if (flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) CHECK_APPEND_2ARG("stripes=%u..%u,", bargs->stripes_min, bargs->stripes_max); #undef CHECK_APPEND_2ARG #undef CHECK_APPEND_1ARG #undef CHECK_APPEND_NOARG out_overflow: if (size_bp < size_buf) buf[size_buf - size_bp - 1] = '\0'; /* remove last , */ else buf[0] = '\0'; } static void describe_balance_start_or_resume(struct btrfs_fs_info *fs_info) { u32 size_buf = 1024; char tmp_buf[192] = {'\0'}; char *buf; char *bp; u32 size_bp = size_buf; int ret; struct btrfs_balance_control *bctl = fs_info->balance_ctl; buf = kzalloc(size_buf, GFP_KERNEL); if (!buf) return; bp = buf; #define CHECK_APPEND_1ARG(a, v1) \ do { \ ret = snprintf(bp, size_bp, (a), (v1)); \ if (ret < 0 || ret >= size_bp) \ goto out_overflow; \ size_bp -= ret; \ bp += ret; \ } while (0) if (bctl->flags & BTRFS_BALANCE_FORCE) CHECK_APPEND_1ARG("%s", "-f "); if (bctl->flags & BTRFS_BALANCE_DATA) { describe_balance_args(&bctl->data, tmp_buf, sizeof(tmp_buf)); CHECK_APPEND_1ARG("-d%s ", tmp_buf); } if (bctl->flags & BTRFS_BALANCE_METADATA) { describe_balance_args(&bctl->meta, tmp_buf, sizeof(tmp_buf)); CHECK_APPEND_1ARG("-m%s ", tmp_buf); } if (bctl->flags & BTRFS_BALANCE_SYSTEM) { describe_balance_args(&bctl->sys, tmp_buf, sizeof(tmp_buf)); CHECK_APPEND_1ARG("-s%s ", tmp_buf); } #undef CHECK_APPEND_1ARG out_overflow: if (size_bp < size_buf) buf[size_buf - size_bp - 1] = '\0'; /* remove last " " */ btrfs_info(fs_info, "balance: %s %s", (bctl->flags & BTRFS_BALANCE_RESUME) ? "resume" : "start", buf); kfree(buf); } /* * Should be called with balance mutexe held */ int btrfs_balance(struct btrfs_fs_info *fs_info, struct btrfs_balance_control *bctl, struct btrfs_ioctl_balance_args *bargs) { u64 meta_target, data_target; u64 allowed; int mixed = 0; int ret; u64 num_devices; unsigned seq; bool reducing_redundancy; bool paused = false; int i; if (btrfs_fs_closing(fs_info) || atomic_read(&fs_info->balance_pause_req) || btrfs_should_cancel_balance(fs_info)) { ret = -EINVAL; goto out; } allowed = btrfs_super_incompat_flags(fs_info->super_copy); if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) mixed = 1; /* * In case of mixed groups both data and meta should be picked, * and identical options should be given for both of them. */ allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; if (mixed && (bctl->flags & allowed)) { if (!(bctl->flags & BTRFS_BALANCE_DATA) || !(bctl->flags & BTRFS_BALANCE_METADATA) || memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { btrfs_err(fs_info, "balance: mixed groups data and metadata options must be the same"); ret = -EINVAL; goto out; } } /* * rw_devices will not change at the moment, device add/delete/replace * are exclusive */ num_devices = fs_info->fs_devices->rw_devices; /* * SINGLE profile on-disk has no profile bit, but in-memory we have a * special bit for it, to make it easier to distinguish. Thus we need * to set it manually, or balance would refuse the profile. */ allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) if (num_devices >= btrfs_raid_array[i].devs_min) allowed |= btrfs_raid_array[i].bg_flag; if (!validate_convert_profile(fs_info, &bctl->data, allowed, "data") || !validate_convert_profile(fs_info, &bctl->meta, allowed, "metadata") || !validate_convert_profile(fs_info, &bctl->sys, allowed, "system")) { ret = -EINVAL; goto out; } /* * Allow to reduce metadata or system integrity only if force set for * profiles with redundancy (copies, parity) */ allowed = 0; for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) { if (btrfs_raid_array[i].ncopies >= 2 || btrfs_raid_array[i].tolerated_failures >= 1) allowed |= btrfs_raid_array[i].bg_flag; } do { seq = read_seqbegin(&fs_info->profiles_lock); if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && (fs_info->avail_system_alloc_bits & allowed) && !(bctl->sys.target & allowed)) || ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && (fs_info->avail_metadata_alloc_bits & allowed) && !(bctl->meta.target & allowed))) reducing_redundancy = true; else reducing_redundancy = false; /* if we're not converting, the target field is uninitialized */ meta_target = (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) ? bctl->meta.target : fs_info->avail_metadata_alloc_bits; data_target = (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) ? bctl->data.target : fs_info->avail_data_alloc_bits; } while (read_seqretry(&fs_info->profiles_lock, seq)); if (reducing_redundancy) { if (bctl->flags & BTRFS_BALANCE_FORCE) { btrfs_info(fs_info, "balance: force reducing metadata redundancy"); } else { btrfs_err(fs_info, "balance: reduces metadata redundancy, use --force if you want this"); ret = -EINVAL; goto out; } } if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) < btrfs_get_num_tolerated_disk_barrier_failures(data_target)) { btrfs_warn(fs_info, "balance: metadata profile %s has lower redundancy than data profile %s", btrfs_bg_type_to_raid_name(meta_target), btrfs_bg_type_to_raid_name(data_target)); } ret = insert_balance_item(fs_info, bctl); if (ret && ret != -EEXIST) goto out; if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { BUG_ON(ret == -EEXIST); BUG_ON(fs_info->balance_ctl); spin_lock(&fs_info->balance_lock); fs_info->balance_ctl = bctl; spin_unlock(&fs_info->balance_lock); } else { BUG_ON(ret != -EEXIST); spin_lock(&fs_info->balance_lock); update_balance_args(bctl); spin_unlock(&fs_info->balance_lock); } ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); set_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags); describe_balance_start_or_resume(fs_info); mutex_unlock(&fs_info->balance_mutex); ret = __btrfs_balance(fs_info); mutex_lock(&fs_info->balance_mutex); if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) { btrfs_info(fs_info, "balance: paused"); btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED); paused = true; } /* * Balance can be canceled by: * * - Regular cancel request * Then ret == -ECANCELED and balance_cancel_req > 0 * * - Fatal signal to "btrfs" process * Either the signal caught by wait_reserve_ticket() and callers * got -EINTR, or caught by btrfs_should_cancel_balance() and * got -ECANCELED. * Either way, in this case balance_cancel_req = 0, and * ret == -EINTR or ret == -ECANCELED. * * So here we only check the return value to catch canceled balance. */ else if (ret == -ECANCELED || ret == -EINTR) btrfs_info(fs_info, "balance: canceled"); else btrfs_info(fs_info, "balance: ended with status: %d", ret); clear_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags); if (bargs) { memset(bargs, 0, sizeof(*bargs)); btrfs_update_ioctl_balance_args(fs_info, bargs); } /* We didn't pause, we can clean everything up. */ if (!paused) { reset_balance_state(fs_info); btrfs_exclop_finish(fs_info); } wake_up(&fs_info->balance_wait_q); return ret; out: if (bctl->flags & BTRFS_BALANCE_RESUME) reset_balance_state(fs_info); else kfree(bctl); btrfs_exclop_finish(fs_info); return ret; } static int balance_kthread(void *data) { struct btrfs_fs_info *fs_info = data; int ret = 0; sb_start_write(fs_info->sb); mutex_lock(&fs_info->balance_mutex); if (fs_info->balance_ctl) ret = btrfs_balance(fs_info, fs_info->balance_ctl, NULL); mutex_unlock(&fs_info->balance_mutex); sb_end_write(fs_info->sb); return ret; } int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) { struct task_struct *tsk; mutex_lock(&fs_info->balance_mutex); if (!fs_info->balance_ctl) { mutex_unlock(&fs_info->balance_mutex); return 0; } mutex_unlock(&fs_info->balance_mutex); if (btrfs_test_opt(fs_info, SKIP_BALANCE)) { btrfs_info(fs_info, "balance: resume skipped"); return 0; } spin_lock(&fs_info->super_lock); ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED); fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE; spin_unlock(&fs_info->super_lock); /* * A ro->rw remount sequence should continue with the paused balance * regardless of who pauses it, system or the user as of now, so set * the resume flag. */ spin_lock(&fs_info->balance_lock); fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME; spin_unlock(&fs_info->balance_lock); tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); return PTR_ERR_OR_ZERO(tsk); } int btrfs_recover_balance(struct btrfs_fs_info *fs_info) { struct btrfs_balance_control *bctl; struct btrfs_balance_item *item; struct btrfs_disk_balance_args disk_bargs; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; key.objectid = BTRFS_BALANCE_OBJECTID; key.type = BTRFS_TEMPORARY_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); if (ret < 0) goto out; if (ret > 0) { /* ret = -ENOENT; */ ret = 0; goto out; } bctl = kzalloc(sizeof(*bctl), GFP_NOFS); if (!bctl) { ret = -ENOMEM; goto out; } leaf = path->nodes[0]; item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); bctl->flags = btrfs_balance_flags(leaf, item); bctl->flags |= BTRFS_BALANCE_RESUME; btrfs_balance_data(leaf, item, &disk_bargs); btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); btrfs_balance_meta(leaf, item, &disk_bargs); btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); btrfs_balance_sys(leaf, item, &disk_bargs); btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); /* * This should never happen, as the paused balance state is recovered * during mount without any chance of other exclusive ops to collide. * * This gives the exclusive op status to balance and keeps in paused * state until user intervention (cancel or umount). If the ownership * cannot be assigned, show a message but do not fail. The balance * is in a paused state and must have fs_info::balance_ctl properly * set up. */ if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED)) btrfs_warn(fs_info, "balance: cannot set exclusive op status, resume manually"); btrfs_release_path(path); mutex_lock(&fs_info->balance_mutex); BUG_ON(fs_info->balance_ctl); spin_lock(&fs_info->balance_lock); fs_info->balance_ctl = bctl; spin_unlock(&fs_info->balance_lock); mutex_unlock(&fs_info->balance_mutex); out: btrfs_free_path(path); return ret; } int btrfs_pause_balance(struct btrfs_fs_info *fs_info) { int ret = 0; mutex_lock(&fs_info->balance_mutex); if (!fs_info->balance_ctl) { mutex_unlock(&fs_info->balance_mutex); return -ENOTCONN; } if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { atomic_inc(&fs_info->balance_pause_req); mutex_unlock(&fs_info->balance_mutex); wait_event(fs_info->balance_wait_q, !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); mutex_lock(&fs_info->balance_mutex); /* we are good with balance_ctl ripped off from under us */ BUG_ON(test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); atomic_dec(&fs_info->balance_pause_req); } else { ret = -ENOTCONN; } mutex_unlock(&fs_info->balance_mutex); return ret; } int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) { mutex_lock(&fs_info->balance_mutex); if (!fs_info->balance_ctl) { mutex_unlock(&fs_info->balance_mutex); return -ENOTCONN; } /* * A paused balance with the item stored on disk can be resumed at * mount time if the mount is read-write. Otherwise it's still paused * and we must not allow cancelling as it deletes the item. */ if (sb_rdonly(fs_info->sb)) { mutex_unlock(&fs_info->balance_mutex); return -EROFS; } atomic_inc(&fs_info->balance_cancel_req); /* * if we are running just wait and return, balance item is * deleted in btrfs_balance in this case */ if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { mutex_unlock(&fs_info->balance_mutex); wait_event(fs_info->balance_wait_q, !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); mutex_lock(&fs_info->balance_mutex); } else { mutex_unlock(&fs_info->balance_mutex); /* * Lock released to allow other waiters to continue, we'll * reexamine the status again. */ mutex_lock(&fs_info->balance_mutex); if (fs_info->balance_ctl) { reset_balance_state(fs_info); btrfs_exclop_finish(fs_info); btrfs_info(fs_info, "balance: canceled"); } } ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); atomic_dec(&fs_info->balance_cancel_req); mutex_unlock(&fs_info->balance_mutex); return 0; } int btrfs_uuid_scan_kthread(void *data) { struct btrfs_fs_info *fs_info = data; struct btrfs_root *root = fs_info->tree_root; struct btrfs_key key; struct btrfs_path *path = NULL; int ret = 0; struct extent_buffer *eb; int slot; struct btrfs_root_item root_item; u32 item_size; struct btrfs_trans_handle *trans = NULL; bool closing = false; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } key.objectid = 0; key.type = BTRFS_ROOT_ITEM_KEY; key.offset = 0; while (1) { if (btrfs_fs_closing(fs_info)) { closing = true; break; } ret = btrfs_search_forward(root, &key, path, BTRFS_OLDEST_GENERATION); if (ret) { if (ret > 0) ret = 0; break; } if (key.type != BTRFS_ROOT_ITEM_KEY || (key.objectid < BTRFS_FIRST_FREE_OBJECTID && key.objectid != BTRFS_FS_TREE_OBJECTID) || key.objectid > BTRFS_LAST_FREE_OBJECTID) goto skip; eb = path->nodes[0]; slot = path->slots[0]; item_size = btrfs_item_size(eb, slot); if (item_size < sizeof(root_item)) goto skip; read_extent_buffer(eb, &root_item, btrfs_item_ptr_offset(eb, slot), (int)sizeof(root_item)); if (btrfs_root_refs(&root_item) == 0) goto skip; if (!btrfs_is_empty_uuid(root_item.uuid) || !btrfs_is_empty_uuid(root_item.received_uuid)) { if (trans) goto update_tree; btrfs_release_path(path); /* * 1 - subvol uuid item * 1 - received_subvol uuid item */ trans = btrfs_start_transaction(fs_info->uuid_root, 2); if (IS_ERR(trans)) { ret = PTR_ERR(trans); break; } continue; } else { goto skip; } update_tree: btrfs_release_path(path); if (!btrfs_is_empty_uuid(root_item.uuid)) { ret = btrfs_uuid_tree_add(trans, root_item.uuid, BTRFS_UUID_KEY_SUBVOL, key.objectid); if (ret < 0) { btrfs_warn(fs_info, "uuid_tree_add failed %d", ret); break; } } if (!btrfs_is_empty_uuid(root_item.received_uuid)) { ret = btrfs_uuid_tree_add(trans, root_item.received_uuid, BTRFS_UUID_KEY_RECEIVED_SUBVOL, key.objectid); if (ret < 0) { btrfs_warn(fs_info, "uuid_tree_add failed %d", ret); break; } } skip: btrfs_release_path(path); if (trans) { ret = btrfs_end_transaction(trans); trans = NULL; if (ret) break; } if (key.offset < (u64)-1) { key.offset++; } else if (key.type < BTRFS_ROOT_ITEM_KEY) { key.offset = 0; key.type = BTRFS_ROOT_ITEM_KEY; } else if (key.objectid < (u64)-1) { key.offset = 0; key.type = BTRFS_ROOT_ITEM_KEY; key.objectid++; } else { break; } cond_resched(); } out: btrfs_free_path(path); if (trans && !IS_ERR(trans)) btrfs_end_transaction(trans); if (ret) btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret); else if (!closing) set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags); up(&fs_info->uuid_tree_rescan_sem); return 0; } int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info) { struct btrfs_trans_handle *trans; struct btrfs_root *tree_root = fs_info->tree_root; struct btrfs_root *uuid_root; struct task_struct *task; int ret; /* * 1 - root node * 1 - root item */ trans = btrfs_start_transaction(tree_root, 2); if (IS_ERR(trans)) return PTR_ERR(trans); uuid_root = btrfs_create_tree(trans, BTRFS_UUID_TREE_OBJECTID); if (IS_ERR(uuid_root)) { ret = PTR_ERR(uuid_root); btrfs_abort_transaction(trans, ret); btrfs_end_transaction(trans); return ret; } fs_info->uuid_root = uuid_root; ret = btrfs_commit_transaction(trans); if (ret) return ret; down(&fs_info->uuid_tree_rescan_sem); task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid"); if (IS_ERR(task)) { /* fs_info->update_uuid_tree_gen remains 0 in all error case */ btrfs_warn(fs_info, "failed to start uuid_scan task"); up(&fs_info->uuid_tree_rescan_sem); return PTR_ERR(task); } return 0; } /* * shrinking a device means finding all of the device extents past * the new size, and then following the back refs to the chunks. * The chunk relocation code actually frees the device extent */ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) { struct btrfs_fs_info *fs_info = device->fs_info; struct btrfs_root *root = fs_info->dev_root; struct btrfs_trans_handle *trans; struct btrfs_dev_extent *dev_extent = NULL; struct btrfs_path *path; u64 length; u64 chunk_offset; int ret; int slot; int failed = 0; bool retried = false; struct extent_buffer *l; struct btrfs_key key; struct btrfs_super_block *super_copy = fs_info->super_copy; u64 old_total = btrfs_super_total_bytes(super_copy); u64 old_size = btrfs_device_get_total_bytes(device); u64 diff; u64 start; u64 free_diff = 0; new_size = round_down(new_size, fs_info->sectorsize); start = new_size; diff = round_down(old_size - new_size, fs_info->sectorsize); if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) return -EINVAL; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = READA_BACK; trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { btrfs_free_path(path); return PTR_ERR(trans); } mutex_lock(&fs_info->chunk_mutex); btrfs_device_set_total_bytes(device, new_size); if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { device->fs_devices->total_rw_bytes -= diff; /* * The new free_chunk_space is new_size - used, so we have to * subtract the delta of the old free_chunk_space which included * old_size - used. If used > new_size then just subtract this * entire device's free space. */ if (device->bytes_used < new_size) free_diff = (old_size - device->bytes_used) - (new_size - device->bytes_used); else free_diff = old_size - device->bytes_used; atomic64_sub(free_diff, &fs_info->free_chunk_space); } /* * Once the device's size has been set to the new size, ensure all * in-memory chunks are synced to disk so that the loop below sees them * and relocates them accordingly. */ if (contains_pending_extent(device, &start, diff)) { mutex_unlock(&fs_info->chunk_mutex); ret = btrfs_commit_transaction(trans); if (ret) goto done; } else { mutex_unlock(&fs_info->chunk_mutex); btrfs_end_transaction(trans); } again: key.objectid = device->devid; key.offset = (u64)-1; key.type = BTRFS_DEV_EXTENT_KEY; do { mutex_lock(&fs_info->reclaim_bgs_lock); ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) { mutex_unlock(&fs_info->reclaim_bgs_lock); goto done; } ret = btrfs_previous_item(root, path, 0, key.type); if (ret) { mutex_unlock(&fs_info->reclaim_bgs_lock); if (ret < 0) goto done; ret = 0; btrfs_release_path(path); break; } l = path->nodes[0]; slot = path->slots[0]; btrfs_item_key_to_cpu(l, &key, path->slots[0]); if (key.objectid != device->devid) { mutex_unlock(&fs_info->reclaim_bgs_lock); btrfs_release_path(path); break; } dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); length = btrfs_dev_extent_length(l, dev_extent); if (key.offset + length <= new_size) { mutex_unlock(&fs_info->reclaim_bgs_lock); btrfs_release_path(path); break; } chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); btrfs_release_path(path); /* * We may be relocating the only data chunk we have, * which could potentially end up with losing data's * raid profile, so lets allocate an empty one in * advance. */ ret = btrfs_may_alloc_data_chunk(fs_info, chunk_offset); if (ret < 0) { mutex_unlock(&fs_info->reclaim_bgs_lock); goto done; } ret = btrfs_relocate_chunk(fs_info, chunk_offset); mutex_unlock(&fs_info->reclaim_bgs_lock); if (ret == -ENOSPC) { failed++; } else if (ret) { if (ret == -ETXTBSY) { btrfs_warn(fs_info, "could not shrink block group %llu due to active swapfile", chunk_offset); } goto done; } } while (key.offset-- > 0); if (failed && !retried) { failed = 0; retried = true; goto again; } else if (failed && retried) { ret = -ENOSPC; goto done; } /* Shrinking succeeded, else we would be at "done". */ trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto done; } mutex_lock(&fs_info->chunk_mutex); /* Clear all state bits beyond the shrunk device size */ clear_extent_bits(&device->alloc_state, new_size, (u64)-1, CHUNK_STATE_MASK); btrfs_device_set_disk_total_bytes(device, new_size); if (list_empty(&device->post_commit_list)) list_add_tail(&device->post_commit_list, &trans->transaction->dev_update_list); WARN_ON(diff > old_total); btrfs_set_super_total_bytes(super_copy, round_down(old_total - diff, fs_info->sectorsize)); mutex_unlock(&fs_info->chunk_mutex); btrfs_reserve_chunk_metadata(trans, false); /* Now btrfs_update_device() will change the on-disk size. */ ret = btrfs_update_device(trans, device); btrfs_trans_release_chunk_metadata(trans); if (ret < 0) { btrfs_abort_transaction(trans, ret); btrfs_end_transaction(trans); } else { ret = btrfs_commit_transaction(trans); } done: btrfs_free_path(path); if (ret) { mutex_lock(&fs_info->chunk_mutex); btrfs_device_set_total_bytes(device, old_size); if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { device->fs_devices->total_rw_bytes += diff; atomic64_add(free_diff, &fs_info->free_chunk_space); } mutex_unlock(&fs_info->chunk_mutex); } return ret; } static int btrfs_add_system_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key, struct btrfs_chunk *chunk, int item_size) { struct btrfs_super_block *super_copy = fs_info->super_copy; struct btrfs_disk_key disk_key; u32 array_size; u8 *ptr; lockdep_assert_held(&fs_info->chunk_mutex); array_size = btrfs_super_sys_array_size(super_copy); if (array_size + item_size + sizeof(disk_key) > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) return -EFBIG; ptr = super_copy->sys_chunk_array + array_size; btrfs_cpu_key_to_disk(&disk_key, key); memcpy(ptr, &disk_key, sizeof(disk_key)); ptr += sizeof(disk_key); memcpy(ptr, chunk, item_size); item_size += sizeof(disk_key); btrfs_set_super_sys_array_size(super_copy, array_size + item_size); return 0; } /* * sort the devices in descending order by max_avail, total_avail */ static int btrfs_cmp_device_info(const void *a, const void *b) { const struct btrfs_device_info *di_a = a; const struct btrfs_device_info *di_b = b; if (di_a->max_avail > di_b->max_avail) return -1; if (di_a->max_avail < di_b->max_avail) return 1; if (di_a->total_avail > di_b->total_avail) return -1; if (di_a->total_avail < di_b->total_avail) return 1; return 0; } static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type) { if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK)) return; btrfs_set_fs_incompat(info, RAID56); } static void check_raid1c34_incompat_flag(struct btrfs_fs_info *info, u64 type) { if (!(type & (BTRFS_BLOCK_GROUP_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4))) return; btrfs_set_fs_incompat(info, RAID1C34); } /* * Structure used internally for btrfs_create_chunk() function. * Wraps needed parameters. */ struct alloc_chunk_ctl { u64 start; u64 type; /* Total number of stripes to allocate */ int num_stripes; /* sub_stripes info for map */ int sub_stripes; /* Stripes per device */ int dev_stripes; /* Maximum number of devices to use */ int devs_max; /* Minimum number of devices to use */ int devs_min; /* ndevs has to be a multiple of this */ int devs_increment; /* Number of copies */ int ncopies; /* Number of stripes worth of bytes to store parity information */ int nparity; u64 max_stripe_size; u64 max_chunk_size; u64 dev_extent_min; u64 stripe_size; u64 chunk_size; int ndevs; }; static void init_alloc_chunk_ctl_policy_regular( struct btrfs_fs_devices *fs_devices, struct alloc_chunk_ctl *ctl) { struct btrfs_space_info *space_info; space_info = btrfs_find_space_info(fs_devices->fs_info, ctl->type); ASSERT(space_info); ctl->max_chunk_size = READ_ONCE(space_info->chunk_size); ctl->max_stripe_size = min_t(u64, ctl->max_chunk_size, SZ_1G); if (ctl->type & BTRFS_BLOCK_GROUP_SYSTEM) ctl->devs_max = min_t(int, ctl->devs_max, BTRFS_MAX_DEVS_SYS_CHUNK); /* We don't want a chunk larger than 10% of writable space */ ctl->max_chunk_size = min(mult_perc(fs_devices->total_rw_bytes, 10), ctl->max_chunk_size); ctl->dev_extent_min = btrfs_stripe_nr_to_offset(ctl->dev_stripes); } static void init_alloc_chunk_ctl_policy_zoned( struct btrfs_fs_devices *fs_devices, struct alloc_chunk_ctl *ctl) { u64 zone_size = fs_devices->fs_info->zone_size; u64 limit; int min_num_stripes = ctl->devs_min * ctl->dev_stripes; int min_data_stripes = (min_num_stripes - ctl->nparity) / ctl->ncopies; u64 min_chunk_size = min_data_stripes * zone_size; u64 type = ctl->type; ctl->max_stripe_size = zone_size; if (type & BTRFS_BLOCK_GROUP_DATA) { ctl->max_chunk_size = round_down(BTRFS_MAX_DATA_CHUNK_SIZE, zone_size); } else if (type & BTRFS_BLOCK_GROUP_METADATA) { ctl->max_chunk_size = ctl->max_stripe_size; } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { ctl->max_chunk_size = 2 * ctl->max_stripe_size; ctl->devs_max = min_t(int, ctl->devs_max, BTRFS_MAX_DEVS_SYS_CHUNK); } else { BUG(); } /* We don't want a chunk larger than 10% of writable space */ limit = max(round_down(mult_perc(fs_devices->total_rw_bytes, 10), zone_size), min_chunk_size); ctl->max_chunk_size = min(limit, ctl->max_chunk_size); ctl->dev_extent_min = zone_size * ctl->dev_stripes; } static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices, struct alloc_chunk_ctl *ctl) { int index = btrfs_bg_flags_to_raid_index(ctl->type); ctl->sub_stripes = btrfs_raid_array[index].sub_stripes; ctl->dev_stripes = btrfs_raid_array[index].dev_stripes; ctl->devs_max = btrfs_raid_array[index].devs_max; if (!ctl->devs_max) ctl->devs_max = BTRFS_MAX_DEVS(fs_devices->fs_info); ctl->devs_min = btrfs_raid_array[index].devs_min; ctl->devs_increment = btrfs_raid_array[index].devs_increment; ctl->ncopies = btrfs_raid_array[index].ncopies; ctl->nparity = btrfs_raid_array[index].nparity; ctl->ndevs = 0; switch (fs_devices->chunk_alloc_policy) { case BTRFS_CHUNK_ALLOC_REGULAR: init_alloc_chunk_ctl_policy_regular(fs_devices, ctl); break; case BTRFS_CHUNK_ALLOC_ZONED: init_alloc_chunk_ctl_policy_zoned(fs_devices, ctl); break; default: BUG(); } } static int gather_device_info(struct btrfs_fs_devices *fs_devices, struct alloc_chunk_ctl *ctl, struct btrfs_device_info *devices_info) { struct btrfs_fs_info *info = fs_devices->fs_info; struct btrfs_device *device; u64 total_avail; u64 dev_extent_want = ctl->max_stripe_size * ctl->dev_stripes; int ret; int ndevs = 0; u64 max_avail; u64 dev_offset; /* * in the first pass through the devices list, we gather information * about the available holes on each device. */ list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) { if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { WARN(1, KERN_ERR "BTRFS: read-only device in alloc_list\n"); continue; } if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state) || test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) continue; if (device->total_bytes > device->bytes_used) total_avail = device->total_bytes - device->bytes_used; else total_avail = 0; /* If there is no space on this device, skip it. */ if (total_avail < ctl->dev_extent_min) continue; ret = find_free_dev_extent(device, dev_extent_want, &dev_offset, &max_avail); if (ret && ret != -ENOSPC) return ret; if (ret == 0) max_avail = dev_extent_want; if (max_avail < ctl->dev_extent_min) { if (btrfs_test_opt(info, ENOSPC_DEBUG)) btrfs_debug(info, "%s: devid %llu has no free space, have=%llu want=%llu", __func__, device->devid, max_avail, ctl->dev_extent_min); continue; } if (ndevs == fs_devices->rw_devices) { WARN(1, "%s: found more than %llu devices\n", __func__, fs_devices->rw_devices); break; } devices_info[ndevs].dev_offset = dev_offset; devices_info[ndevs].max_avail = max_avail; devices_info[ndevs].total_avail = total_avail; devices_info[ndevs].dev = device; ++ndevs; } ctl->ndevs = ndevs; /* * now sort the devices by hole size / available space */ sort(devices_info, ndevs, sizeof(struct btrfs_device_info), btrfs_cmp_device_info, NULL); return 0; } static int decide_stripe_size_regular(struct alloc_chunk_ctl *ctl, struct btrfs_device_info *devices_info) { /* Number of stripes that count for block group size */ int data_stripes; /* * The primary goal is to maximize the number of stripes, so use as * many devices as possible, even if the stripes are not maximum sized. * * The DUP profile stores more than one stripe per device, the * max_avail is the total size so we have to adjust. */ ctl->stripe_size = div_u64(devices_info[ctl->ndevs - 1].max_avail, ctl->dev_stripes); ctl->num_stripes = ctl->ndevs * ctl->dev_stripes; /* This will have to be fixed for RAID1 and RAID10 over more drives */ data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies; /* * Use the number of data stripes to figure out how big this chunk is * really going to be in terms of logical address space, and compare * that answer with the max chunk size. If it's higher, we try to * reduce stripe_size. */ if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) { /* * Reduce stripe_size, round it up to a 16MB boundary again and * then use it, unless it ends up being even bigger than the * previous value we had already. */ ctl->stripe_size = min(round_up(div_u64(ctl->max_chunk_size, data_stripes), SZ_16M), ctl->stripe_size); } /* Stripe size should not go beyond 1G. */ ctl->stripe_size = min_t(u64, ctl->stripe_size, SZ_1G); /* Align to BTRFS_STRIPE_LEN */ ctl->stripe_size = round_down(ctl->stripe_size, BTRFS_STRIPE_LEN); ctl->chunk_size = ctl->stripe_size * data_stripes; return 0; } static int decide_stripe_size_zoned(struct alloc_chunk_ctl *ctl, struct btrfs_device_info *devices_info) { u64 zone_size = devices_info[0].dev->zone_info->zone_size; /* Number of stripes that count for block group size */ int data_stripes; /* * It should hold because: * dev_extent_min == dev_extent_want == zone_size * dev_stripes */ ASSERT(devices_info[ctl->ndevs - 1].max_avail == ctl->dev_extent_min); ctl->stripe_size = zone_size; ctl->num_stripes = ctl->ndevs * ctl->dev_stripes; data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies; /* stripe_size is fixed in zoned filesysmte. Reduce ndevs instead. */ if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) { ctl->ndevs = div_u64(div_u64(ctl->max_chunk_size * ctl->ncopies, ctl->stripe_size) + ctl->nparity, ctl->dev_stripes); ctl->num_stripes = ctl->ndevs * ctl->dev_stripes; data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies; ASSERT(ctl->stripe_size * data_stripes <= ctl->max_chunk_size); } ctl->chunk_size = ctl->stripe_size * data_stripes; return 0; } static int decide_stripe_size(struct btrfs_fs_devices *fs_devices, struct alloc_chunk_ctl *ctl, struct btrfs_device_info *devices_info) { struct btrfs_fs_info *info = fs_devices->fs_info; /* * Round down to number of usable stripes, devs_increment can be any * number so we can't use round_down() that requires power of 2, while * rounddown is safe. */ ctl->ndevs = rounddown(ctl->ndevs, ctl->devs_increment); if (ctl->ndevs < ctl->devs_min) { if (btrfs_test_opt(info, ENOSPC_DEBUG)) { btrfs_debug(info, "%s: not enough devices with free space: have=%d minimum required=%d", __func__, ctl->ndevs, ctl->devs_min); } return -ENOSPC; } ctl->ndevs = min(ctl->ndevs, ctl->devs_max); switch (fs_devices->chunk_alloc_policy) { case BTRFS_CHUNK_ALLOC_REGULAR: return decide_stripe_size_regular(ctl, devices_info); case BTRFS_CHUNK_ALLOC_ZONED: return decide_stripe_size_zoned(ctl, devices_info); default: BUG(); } } static void chunk_map_device_set_bits(struct btrfs_chunk_map *map, unsigned int bits) { for (int i = 0; i < map->num_stripes; i++) { struct btrfs_io_stripe *stripe = &map->stripes[i]; struct btrfs_device *device = stripe->dev; set_extent_bit(&device->alloc_state, stripe->physical, stripe->physical + map->stripe_size - 1, bits | EXTENT_NOWAIT, NULL); } } static void chunk_map_device_clear_bits(struct btrfs_chunk_map *map, unsigned int bits) { for (int i = 0; i < map->num_stripes; i++) { struct btrfs_io_stripe *stripe = &map->stripes[i]; struct btrfs_device *device = stripe->dev; __clear_extent_bit(&device->alloc_state, stripe->physical, stripe->physical + map->stripe_size - 1, bits | EXTENT_NOWAIT, NULL, NULL); } } void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map) { write_lock(&fs_info->mapping_tree_lock); rb_erase_cached(&map->rb_node, &fs_info->mapping_tree); RB_CLEAR_NODE(&map->rb_node); chunk_map_device_clear_bits(map, CHUNK_ALLOCATED); write_unlock(&fs_info->mapping_tree_lock); /* Once for the tree reference. */ btrfs_free_chunk_map(map); } EXPORT_FOR_TESTS int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map) { struct rb_node **p; struct rb_node *parent = NULL; bool leftmost = true; write_lock(&fs_info->mapping_tree_lock); p = &fs_info->mapping_tree.rb_root.rb_node; while (*p) { struct btrfs_chunk_map *entry; parent = *p; entry = rb_entry(parent, struct btrfs_chunk_map, rb_node); if (map->start < entry->start) { p = &(*p)->rb_left; } else if (map->start > entry->start) { p = &(*p)->rb_right; leftmost = false; } else { write_unlock(&fs_info->mapping_tree_lock); return -EEXIST; } } rb_link_node(&map->rb_node, parent, p); rb_insert_color_cached(&map->rb_node, &fs_info->mapping_tree, leftmost); chunk_map_device_set_bits(map, CHUNK_ALLOCATED); chunk_map_device_clear_bits(map, CHUNK_TRIMMED); write_unlock(&fs_info->mapping_tree_lock); return 0; } EXPORT_FOR_TESTS struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp) { struct btrfs_chunk_map *map; map = kmalloc(btrfs_chunk_map_size(num_stripes), gfp); if (!map) return NULL; refcount_set(&map->refs, 1); RB_CLEAR_NODE(&map->rb_node); return map; } struct btrfs_chunk_map *btrfs_clone_chunk_map(struct btrfs_chunk_map *map, gfp_t gfp) { const int size = btrfs_chunk_map_size(map->num_stripes); struct btrfs_chunk_map *clone; clone = kmemdup(map, size, gfp); if (!clone) return NULL; refcount_set(&clone->refs, 1); RB_CLEAR_NODE(&clone->rb_node); return clone; } static struct btrfs_block_group *create_chunk(struct btrfs_trans_handle *trans, struct alloc_chunk_ctl *ctl, struct btrfs_device_info *devices_info) { struct btrfs_fs_info *info = trans->fs_info; struct btrfs_chunk_map *map; struct btrfs_block_group *block_group; u64 start = ctl->start; u64 type = ctl->type; int ret; int i; int j; map = btrfs_alloc_chunk_map(ctl->num_stripes, GFP_NOFS); if (!map) return ERR_PTR(-ENOMEM); map->start = start; map->chunk_len = ctl->chunk_size; map->stripe_size = ctl->stripe_size; map->type = type; map->io_align = BTRFS_STRIPE_LEN; map->io_width = BTRFS_STRIPE_LEN; map->sub_stripes = ctl->sub_stripes; map->num_stripes = ctl->num_stripes; for (i = 0; i < ctl->ndevs; ++i) { for (j = 0; j < ctl->dev_stripes; ++j) { int s = i * ctl->dev_stripes + j; map->stripes[s].dev = devices_info[i].dev; map->stripes[s].physical = devices_info[i].dev_offset + j * ctl->stripe_size; } } trace_btrfs_chunk_alloc(info, map, start, ctl->chunk_size); ret = btrfs_add_chunk_map(info, map); if (ret) { btrfs_free_chunk_map(map); return ERR_PTR(ret); } block_group = btrfs_make_block_group(trans, type, start, ctl->chunk_size); if (IS_ERR(block_group)) { btrfs_remove_chunk_map(info, map); return block_group; } for (int i = 0; i < map->num_stripes; i++) { struct btrfs_device *dev = map->stripes[i].dev; btrfs_device_set_bytes_used(dev, dev->bytes_used + ctl->stripe_size); if (list_empty(&dev->post_commit_list)) list_add_tail(&dev->post_commit_list, &trans->transaction->dev_update_list); } atomic64_sub(ctl->stripe_size * map->num_stripes, &info->free_chunk_space); check_raid56_incompat_flag(info, type); check_raid1c34_incompat_flag(info, type); return block_group; } struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans, u64 type) { struct btrfs_fs_info *info = trans->fs_info; struct btrfs_fs_devices *fs_devices = info->fs_devices; struct btrfs_device_info *devices_info = NULL; struct alloc_chunk_ctl ctl; struct btrfs_block_group *block_group; int ret; lockdep_assert_held(&info->chunk_mutex); if (!alloc_profile_is_valid(type, 0)) { ASSERT(0); return ERR_PTR(-EINVAL); } if (list_empty(&fs_devices->alloc_list)) { if (btrfs_test_opt(info, ENOSPC_DEBUG)) btrfs_debug(info, "%s: no writable device", __func__); return ERR_PTR(-ENOSPC); } if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) { btrfs_err(info, "invalid chunk type 0x%llx requested", type); ASSERT(0); return ERR_PTR(-EINVAL); } ctl.start = find_next_chunk(info); ctl.type = type; init_alloc_chunk_ctl(fs_devices, &ctl); devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info), GFP_NOFS); if (!devices_info) return ERR_PTR(-ENOMEM); ret = gather_device_info(fs_devices, &ctl, devices_info); if (ret < 0) { block_group = ERR_PTR(ret); goto out; } ret = decide_stripe_size(fs_devices, &ctl, devices_info); if (ret < 0) { block_group = ERR_PTR(ret); goto out; } block_group = create_chunk(trans, &ctl, devices_info); out: kfree(devices_info); return block_group; } /* * This function, btrfs_chunk_alloc_add_chunk_item(), typically belongs to the * phase 1 of chunk allocation. It belongs to phase 2 only when allocating system * chunks. * * See the comment at btrfs_chunk_alloc() for details about the chunk allocation * phases. */ int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans, struct btrfs_block_group *bg) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *chunk_root = fs_info->chunk_root; struct btrfs_key key; struct btrfs_chunk *chunk; struct btrfs_stripe *stripe; struct btrfs_chunk_map *map; size_t item_size; int i; int ret; /* * We take the chunk_mutex for 2 reasons: * * 1) Updates and insertions in the chunk btree must be done while holding * the chunk_mutex, as well as updating the system chunk array in the * superblock. See the comment on top of btrfs_chunk_alloc() for the * details; * * 2) To prevent races with the final phase of a device replace operation * that replaces the device object associated with the map's stripes, * because the device object's id can change at any time during that * final phase of the device replace operation * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the * replaced device and then see it with an ID of BTRFS_DEV_REPLACE_DEVID, * which would cause a failure when updating the device item, which does * not exists, or persisting a stripe of the chunk item with such ID. * Here we can't use the device_list_mutex because our caller already * has locked the chunk_mutex, and the final phase of device replace * acquires both mutexes - first the device_list_mutex and then the * chunk_mutex. Using any of those two mutexes protects us from a * concurrent device replace. */ lockdep_assert_held(&fs_info->chunk_mutex); map = btrfs_get_chunk_map(fs_info, bg->start, bg->length); if (IS_ERR(map)) { ret = PTR_ERR(map); btrfs_abort_transaction(trans, ret); return ret; } item_size = btrfs_chunk_item_size(map->num_stripes); chunk = kzalloc(item_size, GFP_NOFS); if (!chunk) { ret = -ENOMEM; btrfs_abort_transaction(trans, ret); goto out; } for (i = 0; i < map->num_stripes; i++) { struct btrfs_device *device = map->stripes[i].dev; ret = btrfs_update_device(trans, device); if (ret) goto out; } stripe = &chunk->stripe; for (i = 0; i < map->num_stripes; i++) { struct btrfs_device *device = map->stripes[i].dev; const u64 dev_offset = map->stripes[i].physical; btrfs_set_stack_stripe_devid(stripe, device->devid); btrfs_set_stack_stripe_offset(stripe, dev_offset); memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); stripe++; } btrfs_set_stack_chunk_length(chunk, bg->length); btrfs_set_stack_chunk_owner(chunk, BTRFS_EXTENT_TREE_OBJECTID); btrfs_set_stack_chunk_stripe_len(chunk, BTRFS_STRIPE_LEN); btrfs_set_stack_chunk_type(chunk, map->type); btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); btrfs_set_stack_chunk_io_align(chunk, BTRFS_STRIPE_LEN); btrfs_set_stack_chunk_io_width(chunk, BTRFS_STRIPE_LEN); btrfs_set_stack_chunk_sector_size(chunk, fs_info->sectorsize); btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.type = BTRFS_CHUNK_ITEM_KEY; key.offset = bg->start; ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); if (ret) goto out; set_bit(BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED, &bg->runtime_flags); if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { ret = btrfs_add_system_chunk(fs_info, &key, chunk, item_size); if (ret) goto out; } out: kfree(chunk); btrfs_free_chunk_map(map); return ret; } static noinline int init_first_rw_device(struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = trans->fs_info; u64 alloc_profile; struct btrfs_block_group *meta_bg; struct btrfs_block_group *sys_bg; /* * When adding a new device for sprouting, the seed device is read-only * so we must first allocate a metadata and a system chunk. But before * adding the block group items to the extent, device and chunk btrees, * we must first: * * 1) Create both chunks without doing any changes to the btrees, as * otherwise we would get -ENOSPC since the block groups from the * seed device are read-only; * * 2) Add the device item for the new sprout device - finishing the setup * of a new block group requires updating the device item in the chunk * btree, so it must exist when we attempt to do it. The previous step * ensures this does not fail with -ENOSPC. * * After that we can add the block group items to their btrees: * update existing device item in the chunk btree, add a new block group * item to the extent btree, add a new chunk item to the chunk btree and * finally add the new device extent items to the devices btree. */ alloc_profile = btrfs_metadata_alloc_profile(fs_info); meta_bg = btrfs_create_chunk(trans, alloc_profile); if (IS_ERR(meta_bg)) return PTR_ERR(meta_bg); alloc_profile = btrfs_system_alloc_profile(fs_info); sys_bg = btrfs_create_chunk(trans, alloc_profile); if (IS_ERR(sys_bg)) return PTR_ERR(sys_bg); return 0; } static inline int btrfs_chunk_max_errors(struct btrfs_chunk_map *map) { const int index = btrfs_bg_flags_to_raid_index(map->type); return btrfs_raid_array[index].tolerated_failures; } bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset) { struct btrfs_chunk_map *map; int miss_ndevs = 0; int i; bool ret = true; map = btrfs_get_chunk_map(fs_info, chunk_offset, 1); if (IS_ERR(map)) return false; for (i = 0; i < map->num_stripes; i++) { if (test_bit(BTRFS_DEV_STATE_MISSING, &map->stripes[i].dev->dev_state)) { miss_ndevs++; continue; } if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &map->stripes[i].dev->dev_state)) { ret = false; goto end; } } /* * If the number of missing devices is larger than max errors, we can * not write the data into that chunk successfully. */ if (miss_ndevs > btrfs_chunk_max_errors(map)) ret = false; end: btrfs_free_chunk_map(map); return ret; } void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info) { write_lock(&fs_info->mapping_tree_lock); while (!RB_EMPTY_ROOT(&fs_info->mapping_tree.rb_root)) { struct btrfs_chunk_map *map; struct rb_node *node; node = rb_first_cached(&fs_info->mapping_tree); map = rb_entry(node, struct btrfs_chunk_map, rb_node); rb_erase_cached(&map->rb_node, &fs_info->mapping_tree); RB_CLEAR_NODE(&map->rb_node); chunk_map_device_clear_bits(map, CHUNK_ALLOCATED); /* Once for the tree ref. */ btrfs_free_chunk_map(map); cond_resched_rwlock_write(&fs_info->mapping_tree_lock); } write_unlock(&fs_info->mapping_tree_lock); } int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) { struct btrfs_chunk_map *map; enum btrfs_raid_types index; int ret = 1; map = btrfs_get_chunk_map(fs_info, logical, len); if (IS_ERR(map)) /* * We could return errors for these cases, but that could get * ugly and we'd probably do the same thing which is just not do * anything else and exit, so return 1 so the callers don't try * to use other copies. */ return 1; index = btrfs_bg_flags_to_raid_index(map->type); /* Non-RAID56, use their ncopies from btrfs_raid_array. */ if (!(map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)) ret = btrfs_raid_array[index].ncopies; else if (map->type & BTRFS_BLOCK_GROUP_RAID5) ret = 2; else if (map->type & BTRFS_BLOCK_GROUP_RAID6) /* * There could be two corrupted data stripes, we need * to loop retry in order to rebuild the correct data. * * Fail a stripe at a time on every retry except the * stripe under reconstruction. */ ret = map->num_stripes; btrfs_free_chunk_map(map); return ret; } unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info, u64 logical) { struct btrfs_chunk_map *map; unsigned long len = fs_info->sectorsize; if (!btrfs_fs_incompat(fs_info, RAID56)) return len; map = btrfs_get_chunk_map(fs_info, logical, len); if (!WARN_ON(IS_ERR(map))) { if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) len = btrfs_stripe_nr_to_offset(nr_data_stripes(map)); btrfs_free_chunk_map(map); } return len; } int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info, u64 logical, u64 len) { struct btrfs_chunk_map *map; int ret = 0; if (!btrfs_fs_incompat(fs_info, RAID56)) return 0; map = btrfs_get_chunk_map(fs_info, logical, len); if (!WARN_ON(IS_ERR(map))) { if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) ret = 1; btrfs_free_chunk_map(map); } return ret; } static int find_live_mirror(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map, int first, int dev_replace_is_ongoing) { const enum btrfs_read_policy policy = READ_ONCE(fs_info->fs_devices->read_policy); int i; int num_stripes; int preferred_mirror; int tolerance; struct btrfs_device *srcdev; ASSERT((map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10))); if (map->type & BTRFS_BLOCK_GROUP_RAID10) num_stripes = map->sub_stripes; else num_stripes = map->num_stripes; switch (policy) { default: /* Shouldn't happen, just warn and use pid instead of failing */ btrfs_warn_rl(fs_info, "unknown read_policy type %u, reset to pid", policy); WRITE_ONCE(fs_info->fs_devices->read_policy, BTRFS_READ_POLICY_PID); fallthrough; case BTRFS_READ_POLICY_PID: preferred_mirror = first + (current->pid % num_stripes); break; } if (dev_replace_is_ongoing && fs_info->dev_replace.cont_reading_from_srcdev_mode == BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) srcdev = fs_info->dev_replace.srcdev; else srcdev = NULL; /* * try to avoid the drive that is the source drive for a * dev-replace procedure, only choose it if no other non-missing * mirror is available */ for (tolerance = 0; tolerance < 2; tolerance++) { if (map->stripes[preferred_mirror].dev->bdev && (tolerance || map->stripes[preferred_mirror].dev != srcdev)) return preferred_mirror; for (i = first; i < first + num_stripes; i++) { if (map->stripes[i].dev->bdev && (tolerance || map->stripes[i].dev != srcdev)) return i; } } /* we couldn't find one that doesn't fail. Just return something * and the io error handling code will clean up eventually */ return preferred_mirror; } static struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info, u64 logical, u16 total_stripes) { struct btrfs_io_context *bioc; bioc = kzalloc( /* The size of btrfs_io_context */ sizeof(struct btrfs_io_context) + /* Plus the variable array for the stripes */ sizeof(struct btrfs_io_stripe) * (total_stripes), GFP_NOFS); if (!bioc) return NULL; refcount_set(&bioc->refs, 1); bioc->fs_info = fs_info; bioc->replace_stripe_src = -1; bioc->full_stripe_logical = (u64)-1; bioc->logical = logical; return bioc; } void btrfs_get_bioc(struct btrfs_io_context *bioc) { WARN_ON(!refcount_read(&bioc->refs)); refcount_inc(&bioc->refs); } void btrfs_put_bioc(struct btrfs_io_context *bioc) { if (!bioc) return; if (refcount_dec_and_test(&bioc->refs)) kfree(bioc); } /* * Please note that, discard won't be sent to target device of device * replace. */ struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info, u64 logical, u64 *length_ret, u32 *num_stripes) { struct btrfs_chunk_map *map; struct btrfs_discard_stripe *stripes; u64 length = *length_ret; u64 offset; u32 stripe_nr; u32 stripe_nr_end; u32 stripe_cnt; u64 stripe_end_offset; u64 stripe_offset; u32 stripe_index; u32 factor = 0; u32 sub_stripes = 0; u32 stripes_per_dev = 0; u32 remaining_stripes = 0; u32 last_stripe = 0; int ret; int i; map = btrfs_get_chunk_map(fs_info, logical, length); if (IS_ERR(map)) return ERR_CAST(map); /* we don't discard raid56 yet */ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { ret = -EOPNOTSUPP; goto out_free_map; } offset = logical - map->start; length = min_t(u64, map->start + map->chunk_len - logical, length); *length_ret = length; /* * stripe_nr counts the total number of stripes we have to stride * to get to this block */ stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT; /* stripe_offset is the offset of this block in its stripe */ stripe_offset = offset - btrfs_stripe_nr_to_offset(stripe_nr); stripe_nr_end = round_up(offset + length, BTRFS_STRIPE_LEN) >> BTRFS_STRIPE_LEN_SHIFT; stripe_cnt = stripe_nr_end - stripe_nr; stripe_end_offset = btrfs_stripe_nr_to_offset(stripe_nr_end) - (offset + length); /* * after this, stripe_nr is the number of stripes on this * device we have to walk to find the data, and stripe_index is * the number of our device in the stripe array */ *num_stripes = 1; stripe_index = 0; if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { if (map->type & BTRFS_BLOCK_GROUP_RAID0) sub_stripes = 1; else sub_stripes = map->sub_stripes; factor = map->num_stripes / sub_stripes; *num_stripes = min_t(u64, map->num_stripes, sub_stripes * stripe_cnt); stripe_index = stripe_nr % factor; stripe_nr /= factor; stripe_index *= sub_stripes; remaining_stripes = stripe_cnt % factor; stripes_per_dev = stripe_cnt / factor; last_stripe = ((stripe_nr_end - 1) % factor) * sub_stripes; } else if (map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_DUP)) { *num_stripes = map->num_stripes; } else { stripe_index = stripe_nr % map->num_stripes; stripe_nr /= map->num_stripes; } stripes = kcalloc(*num_stripes, sizeof(*stripes), GFP_NOFS); if (!stripes) { ret = -ENOMEM; goto out_free_map; } for (i = 0; i < *num_stripes; i++) { stripes[i].physical = map->stripes[stripe_index].physical + stripe_offset + btrfs_stripe_nr_to_offset(stripe_nr); stripes[i].dev = map->stripes[stripe_index].dev; if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { stripes[i].length = btrfs_stripe_nr_to_offset(stripes_per_dev); if (i / sub_stripes < remaining_stripes) stripes[i].length += BTRFS_STRIPE_LEN; /* * Special for the first stripe and * the last stripe: * * |-------|...|-------| * |----------| * off end_off */ if (i < sub_stripes) stripes[i].length -= stripe_offset; if (stripe_index >= last_stripe && stripe_index <= (last_stripe + sub_stripes - 1)) stripes[i].length -= stripe_end_offset; if (i == sub_stripes - 1) stripe_offset = 0; } else { stripes[i].length = length; } stripe_index++; if (stripe_index == map->num_stripes) { stripe_index = 0; stripe_nr++; } } btrfs_free_chunk_map(map); return stripes; out_free_map: btrfs_free_chunk_map(map); return ERR_PTR(ret); } static bool is_block_group_to_copy(struct btrfs_fs_info *fs_info, u64 logical) { struct btrfs_block_group *cache; bool ret; /* Non zoned filesystem does not use "to_copy" flag */ if (!btrfs_is_zoned(fs_info)) return false; cache = btrfs_lookup_block_group(fs_info, logical); ret = test_bit(BLOCK_GROUP_FLAG_TO_COPY, &cache->runtime_flags); btrfs_put_block_group(cache); return ret; } static void handle_ops_on_dev_replace(enum btrfs_map_op op, struct btrfs_io_context *bioc, struct btrfs_dev_replace *dev_replace, u64 logical, int *num_stripes_ret, int *max_errors_ret) { u64 srcdev_devid = dev_replace->srcdev->devid; /* * At this stage, num_stripes is still the real number of stripes, * excluding the duplicated stripes. */ int num_stripes = *num_stripes_ret; int nr_extra_stripes = 0; int max_errors = *max_errors_ret; int i; /* * A block group which has "to_copy" set will eventually be copied by * the dev-replace process. We can avoid cloning IO here. */ if (is_block_group_to_copy(dev_replace->srcdev->fs_info, logical)) return; /* * Duplicate the write operations while the dev-replace procedure is * running. Since the copying of the old disk to the new disk takes * place at run time while the filesystem is mounted writable, the * regular write operations to the old disk have to be duplicated to go * to the new disk as well. * * Note that device->missing is handled by the caller, and that the * write to the old disk is already set up in the stripes array. */ for (i = 0; i < num_stripes; i++) { struct btrfs_io_stripe *old = &bioc->stripes[i]; struct btrfs_io_stripe *new = &bioc->stripes[num_stripes + nr_extra_stripes]; if (old->dev->devid != srcdev_devid) continue; new->physical = old->physical; new->dev = dev_replace->tgtdev; if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) bioc->replace_stripe_src = i; nr_extra_stripes++; } /* We can only have at most 2 extra nr_stripes (for DUP). */ ASSERT(nr_extra_stripes <= 2); /* * For GET_READ_MIRRORS, we can only return at most 1 extra stripe for * replace. * If we have 2 extra stripes, only choose the one with smaller physical. */ if (op == BTRFS_MAP_GET_READ_MIRRORS && nr_extra_stripes == 2) { struct btrfs_io_stripe *first = &bioc->stripes[num_stripes]; struct btrfs_io_stripe *second = &bioc->stripes[num_stripes + 1]; /* Only DUP can have two extra stripes. */ ASSERT(bioc->map_type & BTRFS_BLOCK_GROUP_DUP); /* * Swap the last stripe stripes and reduce @nr_extra_stripes. * The extra stripe would still be there, but won't be accessed. */ if (first->physical > second->physical) { swap(second->physical, first->physical); swap(second->dev, first->dev); nr_extra_stripes--; } } *num_stripes_ret = num_stripes + nr_extra_stripes; *max_errors_ret = max_errors + nr_extra_stripes; bioc->replace_nr_stripes = nr_extra_stripes; } static u64 btrfs_max_io_len(struct btrfs_chunk_map *map, u64 offset, struct btrfs_io_geometry *io_geom) { /* * Stripe_nr is the stripe where this block falls. stripe_offset is * the offset of this block in its stripe. */ io_geom->stripe_offset = offset & BTRFS_STRIPE_LEN_MASK; io_geom->stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT; ASSERT(io_geom->stripe_offset < U32_MAX); if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { unsigned long full_stripe_len = btrfs_stripe_nr_to_offset(nr_data_stripes(map)); /* * For full stripe start, we use previously calculated * @stripe_nr. Align it to nr_data_stripes, then multiply with * STRIPE_LEN. * * By this we can avoid u64 division completely. And we have * to go rounddown(), not round_down(), as nr_data_stripes is * not ensured to be power of 2. */ io_geom->raid56_full_stripe_start = btrfs_stripe_nr_to_offset( rounddown(io_geom->stripe_nr, nr_data_stripes(map))); ASSERT(io_geom->raid56_full_stripe_start + full_stripe_len > offset); ASSERT(io_geom->raid56_full_stripe_start <= offset); /* * For writes to RAID56, allow to write a full stripe set, but * no straddling of stripe sets. */ if (io_geom->op == BTRFS_MAP_WRITE) return full_stripe_len - (offset - io_geom->raid56_full_stripe_start); } /* * For other RAID types and for RAID56 reads, allow a single stripe (on * a single disk). */ if (map->type & BTRFS_BLOCK_GROUP_STRIPE_MASK) return BTRFS_STRIPE_LEN - io_geom->stripe_offset; return U64_MAX; } static int set_io_stripe(struct btrfs_fs_info *fs_info, u64 logical, u64 *length, struct btrfs_io_stripe *dst, struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom) { dst->dev = map->stripes[io_geom->stripe_index].dev; if (io_geom->op == BTRFS_MAP_READ && btrfs_need_stripe_tree_update(fs_info, map->type)) return btrfs_get_raid_extent_offset(fs_info, logical, length, map->type, io_geom->stripe_index, dst); dst->physical = map->stripes[io_geom->stripe_index].physical + io_geom->stripe_offset + btrfs_stripe_nr_to_offset(io_geom->stripe_nr); return 0; } static bool is_single_device_io(struct btrfs_fs_info *fs_info, const struct btrfs_io_stripe *smap, const struct btrfs_chunk_map *map, int num_alloc_stripes, enum btrfs_map_op op, int mirror_num) { if (!smap) return false; if (num_alloc_stripes != 1) return false; if (btrfs_need_stripe_tree_update(fs_info, map->type) && op != BTRFS_MAP_READ) return false; if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) && mirror_num > 1) return false; return true; } static void map_blocks_raid0(const struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom) { io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes; io_geom->stripe_nr /= map->num_stripes; if (io_geom->op == BTRFS_MAP_READ) io_geom->mirror_num = 1; } static void map_blocks_raid1(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom, bool dev_replace_is_ongoing) { if (io_geom->op != BTRFS_MAP_READ) { io_geom->num_stripes = map->num_stripes; return; } if (io_geom->mirror_num) { io_geom->stripe_index = io_geom->mirror_num - 1; return; } io_geom->stripe_index = find_live_mirror(fs_info, map, 0, dev_replace_is_ongoing); io_geom->mirror_num = io_geom->stripe_index + 1; } static void map_blocks_dup(const struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom) { if (io_geom->op != BTRFS_MAP_READ) { io_geom->num_stripes = map->num_stripes; return; } if (io_geom->mirror_num) { io_geom->stripe_index = io_geom->mirror_num - 1; return; } io_geom->mirror_num = 1; } static void map_blocks_raid10(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom, bool dev_replace_is_ongoing) { u32 factor = map->num_stripes / map->sub_stripes; int old_stripe_index; io_geom->stripe_index = (io_geom->stripe_nr % factor) * map->sub_stripes; io_geom->stripe_nr /= factor; if (io_geom->op != BTRFS_MAP_READ) { io_geom->num_stripes = map->sub_stripes; return; } if (io_geom->mirror_num) { io_geom->stripe_index += io_geom->mirror_num - 1; return; } old_stripe_index = io_geom->stripe_index; io_geom->stripe_index = find_live_mirror(fs_info, map, io_geom->stripe_index, dev_replace_is_ongoing); io_geom->mirror_num = io_geom->stripe_index - old_stripe_index + 1; } static void map_blocks_raid56_write(struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom, u64 logical, u64 *length) { int data_stripes = nr_data_stripes(map); /* * Needs full stripe mapping. * * Push stripe_nr back to the start of the full stripe For those cases * needing a full stripe, @stripe_nr is the full stripe number. * * Originally we go raid56_full_stripe_start / full_stripe_len, but * that can be expensive. Here we just divide @stripe_nr with * @data_stripes. */ io_geom->stripe_nr /= data_stripes; /* RAID[56] write or recovery. Return all stripes */ io_geom->num_stripes = map->num_stripes; io_geom->max_errors = btrfs_chunk_max_errors(map); /* Return the length to the full stripe end. */ *length = min(logical + *length, io_geom->raid56_full_stripe_start + map->start + btrfs_stripe_nr_to_offset(data_stripes)) - logical; io_geom->stripe_index = 0; io_geom->stripe_offset = 0; } static void map_blocks_raid56_read(struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom) { int data_stripes = nr_data_stripes(map); ASSERT(io_geom->mirror_num <= 1); /* Just grab the data stripe directly. */ io_geom->stripe_index = io_geom->stripe_nr % data_stripes; io_geom->stripe_nr /= data_stripes; /* We distribute the parity blocks across stripes. */ io_geom->stripe_index = (io_geom->stripe_nr + io_geom->stripe_index) % map->num_stripes; if (io_geom->op == BTRFS_MAP_READ && io_geom->mirror_num < 1) io_geom->mirror_num = 1; } static void map_blocks_single(const struct btrfs_chunk_map *map, struct btrfs_io_geometry *io_geom) { io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes; io_geom->stripe_nr /= map->num_stripes; io_geom->mirror_num = io_geom->stripe_index + 1; } /* * Map one logical range to one or more physical ranges. * * @length: (Mandatory) mapped length of this run. * One logical range can be split into different segments * due to factors like zones and RAID0/5/6/10 stripe * boundaries. * * @bioc_ret: (Mandatory) returned btrfs_io_context structure. * which has one or more physical ranges (btrfs_io_stripe) * recorded inside. * Caller should call btrfs_put_bioc() to free it after use. * * @smap: (Optional) single physical range optimization. * If the map request can be fulfilled by one single * physical range, and this is parameter is not NULL, * then @bioc_ret would be NULL, and @smap would be * updated. * * @mirror_num_ret: (Mandatory) returned mirror number if the original * value is 0. * * Mirror number 0 means to choose any live mirrors. * * For non-RAID56 profiles, non-zero mirror_num means * the Nth mirror. (e.g. mirror_num 1 means the first * copy). * * For RAID56 profile, mirror 1 means rebuild from P and * the remaining data stripes. * * For RAID6 profile, mirror > 2 means mark another * data/P stripe error and rebuild from the remaining * stripes.. */ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, u64 logical, u64 *length, struct btrfs_io_context **bioc_ret, struct btrfs_io_stripe *smap, int *mirror_num_ret) { struct btrfs_chunk_map *map; struct btrfs_io_geometry io_geom = { 0 }; u64 map_offset; int i; int ret = 0; int num_copies; struct btrfs_io_context *bioc = NULL; struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; int dev_replace_is_ongoing = 0; u16 num_alloc_stripes; u64 max_len; ASSERT(bioc_ret); io_geom.mirror_num = (mirror_num_ret ? *mirror_num_ret : 0); io_geom.num_stripes = 1; io_geom.stripe_index = 0; io_geom.op = op; num_copies = btrfs_num_copies(fs_info, logical, fs_info->sectorsize); if (io_geom.mirror_num > num_copies) return -EINVAL; map = btrfs_get_chunk_map(fs_info, logical, *length); if (IS_ERR(map)) return PTR_ERR(map); map_offset = logical - map->start; io_geom.raid56_full_stripe_start = (u64)-1; max_len = btrfs_max_io_len(map, map_offset, &io_geom); *length = min_t(u64, map->chunk_len - map_offset, max_len); down_read(&dev_replace->rwsem); dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); /* * Hold the semaphore for read during the whole operation, write is * requested at commit time but must wait. */ if (!dev_replace_is_ongoing) up_read(&dev_replace->rwsem); switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { case BTRFS_BLOCK_GROUP_RAID0: map_blocks_raid0(map, &io_geom); break; case BTRFS_BLOCK_GROUP_RAID1: case BTRFS_BLOCK_GROUP_RAID1C3: case BTRFS_BLOCK_GROUP_RAID1C4: map_blocks_raid1(fs_info, map, &io_geom, dev_replace_is_ongoing); break; case BTRFS_BLOCK_GROUP_DUP: map_blocks_dup(map, &io_geom); break; case BTRFS_BLOCK_GROUP_RAID10: map_blocks_raid10(fs_info, map, &io_geom, dev_replace_is_ongoing); break; case BTRFS_BLOCK_GROUP_RAID5: case BTRFS_BLOCK_GROUP_RAID6: if (op != BTRFS_MAP_READ || io_geom.mirror_num > 1) map_blocks_raid56_write(map, &io_geom, logical, length); else map_blocks_raid56_read(map, &io_geom); break; default: /* * After this, stripe_nr is the number of stripes on this * device we have to walk to find the data, and stripe_index is * the number of our device in the stripe array */ map_blocks_single(map, &io_geom); break; } if (io_geom.stripe_index >= map->num_stripes) { btrfs_crit(fs_info, "stripe index math went horribly wrong, got stripe_index=%u, num_stripes=%u", io_geom.stripe_index, map->num_stripes); ret = -EINVAL; goto out; } num_alloc_stripes = io_geom.num_stripes; if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL && op != BTRFS_MAP_READ) /* * For replace case, we need to add extra stripes for extra * duplicated stripes. * * For both WRITE and GET_READ_MIRRORS, we may have at most * 2 more stripes (DUP types, otherwise 1). */ num_alloc_stripes += 2; /* * If this I/O maps to a single device, try to return the device and * physical block information on the stack instead of allocating an * I/O context structure. */ if (is_single_device_io(fs_info, smap, map, num_alloc_stripes, op, io_geom.mirror_num)) { ret = set_io_stripe(fs_info, logical, length, smap, map, &io_geom); if (mirror_num_ret) *mirror_num_ret = io_geom.mirror_num; *bioc_ret = NULL; goto out; } bioc = alloc_btrfs_io_context(fs_info, logical, num_alloc_stripes); if (!bioc) { ret = -ENOMEM; goto out; } bioc->map_type = map->type; /* * For RAID56 full map, we need to make sure the stripes[] follows the * rule that data stripes are all ordered, then followed with P and Q * (if we have). * * It's still mostly the same as other profiles, just with extra rotation. */ if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK && (op != BTRFS_MAP_READ || io_geom.mirror_num > 1)) { /* * For RAID56 @stripe_nr is already the number of full stripes * before us, which is also the rotation value (needs to modulo * with num_stripes). * * In this case, we just add @stripe_nr with @i, then do the * modulo, to reduce one modulo call. */ bioc->full_stripe_logical = map->start + btrfs_stripe_nr_to_offset(io_geom.stripe_nr * nr_data_stripes(map)); for (int i = 0; i < io_geom.num_stripes; i++) { struct btrfs_io_stripe *dst = &bioc->stripes[i]; u32 stripe_index; stripe_index = (i + io_geom.stripe_nr) % io_geom.num_stripes; dst->dev = map->stripes[stripe_index].dev; dst->physical = map->stripes[stripe_index].physical + io_geom.stripe_offset + btrfs_stripe_nr_to_offset(io_geom.stripe_nr); } } else { /* * For all other non-RAID56 profiles, just copy the target * stripe into the bioc. */ for (i = 0; i < io_geom.num_stripes; i++) { ret = set_io_stripe(fs_info, logical, length, &bioc->stripes[i], map, &io_geom); if (ret < 0) break; io_geom.stripe_index++; } } if (ret) { *bioc_ret = NULL; btrfs_put_bioc(bioc); goto out; } if (op != BTRFS_MAP_READ) io_geom.max_errors = btrfs_chunk_max_errors(map); if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL && op != BTRFS_MAP_READ) { handle_ops_on_dev_replace(op, bioc, dev_replace, logical, &io_geom.num_stripes, &io_geom.max_errors); } *bioc_ret = bioc; bioc->num_stripes = io_geom.num_stripes; bioc->max_errors = io_geom.max_errors; bioc->mirror_num = io_geom.mirror_num; out: if (dev_replace_is_ongoing) { lockdep_assert_held(&dev_replace->rwsem); /* Unlock and let waiting writers proceed */ up_read(&dev_replace->rwsem); } btrfs_free_chunk_map(map); return ret; } static bool dev_args_match_fs_devices(const struct btrfs_dev_lookup_args *args, const struct btrfs_fs_devices *fs_devices) { if (args->fsid == NULL) return true; if (memcmp(fs_devices->metadata_uuid, args->fsid, BTRFS_FSID_SIZE) == 0) return true; return false; } static bool dev_args_match_device(const struct btrfs_dev_lookup_args *args, const struct btrfs_device *device) { if (args->missing) { if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state) && !device->bdev) return true; return false; } if (device->devid != args->devid) return false; if (args->uuid && memcmp(device->uuid, args->uuid, BTRFS_UUID_SIZE) != 0) return false; return true; } /* * Find a device specified by @devid or @uuid in the list of @fs_devices, or * return NULL. * * If devid and uuid are both specified, the match must be exact, otherwise * only devid is used. */ struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices, const struct btrfs_dev_lookup_args *args) { struct btrfs_device *device; struct btrfs_fs_devices *seed_devs; if (dev_args_match_fs_devices(args, fs_devices)) { list_for_each_entry(device, &fs_devices->devices, dev_list) { if (dev_args_match_device(args, device)) return device; } } list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) { if (!dev_args_match_fs_devices(args, seed_devs)) continue; list_for_each_entry(device, &seed_devs->devices, dev_list) { if (dev_args_match_device(args, device)) return device; } } return NULL; } static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices, u64 devid, u8 *dev_uuid) { struct btrfs_device *device; unsigned int nofs_flag; /* * We call this under the chunk_mutex, so we want to use NOFS for this * allocation, however we don't want to change btrfs_alloc_device() to * always do NOFS because we use it in a lot of other GFP_KERNEL safe * places. */ nofs_flag = memalloc_nofs_save(); device = btrfs_alloc_device(NULL, &devid, dev_uuid, NULL); memalloc_nofs_restore(nofs_flag); if (IS_ERR(device)) return device; list_add(&device->dev_list, &fs_devices->devices); device->fs_devices = fs_devices; fs_devices->num_devices++; set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); fs_devices->missing_devices++; return device; } /* * Allocate new device struct, set up devid and UUID. * * @fs_info: used only for generating a new devid, can be NULL if * devid is provided (i.e. @devid != NULL). * @devid: a pointer to devid for this device. If NULL a new devid * is generated. * @uuid: a pointer to UUID for this device. If NULL a new UUID * is generated. * @path: a pointer to device path if available, NULL otherwise. * * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR() * on error. Returned struct is not linked onto any lists and must be * destroyed with btrfs_free_device. */ struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, const u64 *devid, const u8 *uuid, const char *path) { struct btrfs_device *dev; u64 tmp; if (WARN_ON(!devid && !fs_info)) return ERR_PTR(-EINVAL); dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (!dev) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&dev->dev_list); INIT_LIST_HEAD(&dev->dev_alloc_list); INIT_LIST_HEAD(&dev->post_commit_list); atomic_set(&dev->dev_stats_ccnt, 0); btrfs_device_data_ordered_init(dev); extent_io_tree_init(fs_info, &dev->alloc_state, IO_TREE_DEVICE_ALLOC_STATE); if (devid) tmp = *devid; else { int ret; ret = find_next_devid(fs_info, &tmp); if (ret) { btrfs_free_device(dev); return ERR_PTR(ret); } } dev->devid = tmp; if (uuid) memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE); else generate_random_uuid(dev->uuid); if (path) { struct rcu_string *name; name = rcu_string_strdup(path, GFP_KERNEL); if (!name) { btrfs_free_device(dev); return ERR_PTR(-ENOMEM); } rcu_assign_pointer(dev->name, name); } return dev; } static void btrfs_report_missing_device(struct btrfs_fs_info *fs_info, u64 devid, u8 *uuid, bool error) { if (error) btrfs_err_rl(fs_info, "devid %llu uuid %pU is missing", devid, uuid); else btrfs_warn_rl(fs_info, "devid %llu uuid %pU is missing", devid, uuid); } u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map) { const int data_stripes = calc_data_stripes(map->type, map->num_stripes); return div_u64(map->chunk_len, data_stripes); } #if BITS_PER_LONG == 32 /* * Due to page cache limit, metadata beyond BTRFS_32BIT_MAX_FILE_SIZE * can't be accessed on 32bit systems. * * This function do mount time check to reject the fs if it already has * metadata chunk beyond that limit. */ static int check_32bit_meta_chunk(struct btrfs_fs_info *fs_info, u64 logical, u64 length, u64 type) { if (!(type & BTRFS_BLOCK_GROUP_METADATA)) return 0; if (logical + length < MAX_LFS_FILESIZE) return 0; btrfs_err_32bit_limit(fs_info); return -EOVERFLOW; } /* * This is to give early warning for any metadata chunk reaching * BTRFS_32BIT_EARLY_WARN_THRESHOLD. * Although we can still access the metadata, it's not going to be possible * once the limit is reached. */ static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info, u64 logical, u64 length, u64 type) { if (!(type & BTRFS_BLOCK_GROUP_METADATA)) return; if (logical + length < BTRFS_32BIT_EARLY_WARN_THRESHOLD) return; btrfs_warn_32bit_limit(fs_info); } #endif static struct btrfs_device *handle_missing_device(struct btrfs_fs_info *fs_info, u64 devid, u8 *uuid) { struct btrfs_device *dev; if (!btrfs_test_opt(fs_info, DEGRADED)) { btrfs_report_missing_device(fs_info, devid, uuid, true); return ERR_PTR(-ENOENT); } dev = add_missing_dev(fs_info->fs_devices, devid, uuid); if (IS_ERR(dev)) { btrfs_err(fs_info, "failed to init missing device %llu: %ld", devid, PTR_ERR(dev)); return dev; } btrfs_report_missing_device(fs_info, devid, uuid, false); return dev; } static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf, struct btrfs_chunk *chunk) { BTRFS_DEV_LOOKUP_ARGS(args); struct btrfs_fs_info *fs_info = leaf->fs_info; struct btrfs_chunk_map *map; u64 logical; u64 length; u64 devid; u64 type; u8 uuid[BTRFS_UUID_SIZE]; int index; int num_stripes; int ret; int i; logical = key->offset; length = btrfs_chunk_length(leaf, chunk); type = btrfs_chunk_type(leaf, chunk); index = btrfs_bg_flags_to_raid_index(type); num_stripes = btrfs_chunk_num_stripes(leaf, chunk); #if BITS_PER_LONG == 32 ret = check_32bit_meta_chunk(fs_info, logical, length, type); if (ret < 0) return ret; warn_32bit_meta_chunk(fs_info, logical, length, type); #endif /* * Only need to verify chunk item if we're reading from sys chunk array, * as chunk item in tree block is already verified by tree-checker. */ if (leaf->start == BTRFS_SUPER_INFO_OFFSET) { ret = btrfs_check_chunk_valid(leaf, chunk, logical); if (ret) return ret; } map = btrfs_find_chunk_map(fs_info, logical, 1); /* already mapped? */ if (map && map->start <= logical && map->start + map->chunk_len > logical) { btrfs_free_chunk_map(map); return 0; } else if (map) { btrfs_free_chunk_map(map); } map = btrfs_alloc_chunk_map(num_stripes, GFP_NOFS); if (!map) return -ENOMEM; map->start = logical; map->chunk_len = length; map->num_stripes = num_stripes; map->io_width = btrfs_chunk_io_width(leaf, chunk); map->io_align = btrfs_chunk_io_align(leaf, chunk); map->type = type; /* * We can't use the sub_stripes value, as for profiles other than * RAID10, they may have 0 as sub_stripes for filesystems created by * older mkfs (sub_stripes = btrfs_raid_array[index].sub_stripes; map->verified_stripes = 0; map->stripe_size = btrfs_calc_stripe_length(map); for (i = 0; i < num_stripes; i++) { map->stripes[i].physical = btrfs_stripe_offset_nr(leaf, chunk, i); devid = btrfs_stripe_devid_nr(leaf, chunk, i); args.devid = devid; read_extent_buffer(leaf, uuid, (unsigned long) btrfs_stripe_dev_uuid_nr(chunk, i), BTRFS_UUID_SIZE); args.uuid = uuid; map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, &args); if (!map->stripes[i].dev) { map->stripes[i].dev = handle_missing_device(fs_info, devid, uuid); if (IS_ERR(map->stripes[i].dev)) { ret = PTR_ERR(map->stripes[i].dev); btrfs_free_chunk_map(map); return ret; } } set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &(map->stripes[i].dev->dev_state)); } ret = btrfs_add_chunk_map(fs_info, map); if (ret < 0) { btrfs_err(fs_info, "failed to add chunk map, start=%llu len=%llu: %d", map->start, map->chunk_len, ret); } return ret; } static void fill_device_from_item(struct extent_buffer *leaf, struct btrfs_dev_item *dev_item, struct btrfs_device *device) { unsigned long ptr; device->devid = btrfs_device_id(leaf, dev_item); device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); device->total_bytes = device->disk_total_bytes; device->commit_total_bytes = device->disk_total_bytes; device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); device->commit_bytes_used = device->bytes_used; device->type = btrfs_device_type(leaf, dev_item); device->io_align = btrfs_device_io_align(leaf, dev_item); device->io_width = btrfs_device_io_width(leaf, dev_item); device->sector_size = btrfs_device_sector_size(leaf, dev_item); WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); ptr = btrfs_device_uuid(dev_item); read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); } static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info, u8 *fsid) { struct btrfs_fs_devices *fs_devices; int ret; lockdep_assert_held(&uuid_mutex); ASSERT(fsid); /* This will match only for multi-device seed fs */ list_for_each_entry(fs_devices, &fs_info->fs_devices->seed_list, seed_list) if (!memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE)) return fs_devices; fs_devices = find_fsid(fsid, NULL); if (!fs_devices) { if (!btrfs_test_opt(fs_info, DEGRADED)) return ERR_PTR(-ENOENT); fs_devices = alloc_fs_devices(fsid); if (IS_ERR(fs_devices)) return fs_devices; fs_devices->seeding = true; fs_devices->opened = 1; return fs_devices; } /* * Upon first call for a seed fs fsid, just create a private copy of the * respective fs_devices and anchor it at fs_info->fs_devices->seed_list */ fs_devices = clone_fs_devices(fs_devices); if (IS_ERR(fs_devices)) return fs_devices; ret = open_fs_devices(fs_devices, BLK_OPEN_READ, fs_info->bdev_holder); if (ret) { free_fs_devices(fs_devices); return ERR_PTR(ret); } if (!fs_devices->seeding) { close_fs_devices(fs_devices); free_fs_devices(fs_devices); return ERR_PTR(-EINVAL); } list_add(&fs_devices->seed_list, &fs_info->fs_devices->seed_list); return fs_devices; } static int read_one_dev(struct extent_buffer *leaf, struct btrfs_dev_item *dev_item) { BTRFS_DEV_LOOKUP_ARGS(args); struct btrfs_fs_info *fs_info = leaf->fs_info; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; struct btrfs_device *device; u64 devid; int ret; u8 fs_uuid[BTRFS_FSID_SIZE]; u8 dev_uuid[BTRFS_UUID_SIZE]; devid = btrfs_device_id(leaf, dev_item); args.devid = devid; read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item), BTRFS_UUID_SIZE); read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item), BTRFS_FSID_SIZE); args.uuid = dev_uuid; args.fsid = fs_uuid; if (memcmp(fs_uuid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE)) { fs_devices = open_seed_devices(fs_info, fs_uuid); if (IS_ERR(fs_devices)) return PTR_ERR(fs_devices); } device = btrfs_find_device(fs_info->fs_devices, &args); if (!device) { if (!btrfs_test_opt(fs_info, DEGRADED)) { btrfs_report_missing_device(fs_info, devid, dev_uuid, true); return -ENOENT; } device = add_missing_dev(fs_devices, devid, dev_uuid); if (IS_ERR(device)) { btrfs_err(fs_info, "failed to add missing dev %llu: %ld", devid, PTR_ERR(device)); return PTR_ERR(device); } btrfs_report_missing_device(fs_info, devid, dev_uuid, false); } else { if (!device->bdev) { if (!btrfs_test_opt(fs_info, DEGRADED)) { btrfs_report_missing_device(fs_info, devid, dev_uuid, true); return -ENOENT; } btrfs_report_missing_device(fs_info, devid, dev_uuid, false); } if (!device->bdev && !test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) { /* * this happens when a device that was properly setup * in the device info lists suddenly goes bad. * device->bdev is NULL, and so we have to set * device->missing to one here */ device->fs_devices->missing_devices++; set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); } /* Move the device to its own fs_devices */ if (device->fs_devices != fs_devices) { ASSERT(test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)); list_move(&device->dev_list, &fs_devices->devices); device->fs_devices->num_devices--; fs_devices->num_devices++; device->fs_devices->missing_devices--; fs_devices->missing_devices++; device->fs_devices = fs_devices; } } if (device->fs_devices != fs_info->fs_devices) { BUG_ON(test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)); if (device->generation != btrfs_device_generation(leaf, dev_item)) return -EINVAL; } fill_device_from_item(leaf, dev_item, device); if (device->bdev) { u64 max_total_bytes = bdev_nr_bytes(device->bdev); if (device->total_bytes > max_total_bytes) { btrfs_err(fs_info, "device total_bytes should be at most %llu but found %llu", max_total_bytes, device->total_bytes); return -EINVAL; } } set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { device->fs_devices->total_rw_bytes += device->total_bytes; atomic64_add(device->total_bytes - device->bytes_used, &fs_info->free_chunk_space); } ret = 0; return ret; } int btrfs_read_sys_array(struct btrfs_fs_info *fs_info) { struct btrfs_super_block *super_copy = fs_info->super_copy; struct extent_buffer *sb; struct btrfs_disk_key *disk_key; struct btrfs_chunk *chunk; u8 *array_ptr; unsigned long sb_array_offset; int ret = 0; u32 num_stripes; u32 array_size; u32 len = 0; u32 cur_offset; u64 type; struct btrfs_key key; ASSERT(BTRFS_SUPER_INFO_SIZE <= fs_info->nodesize); /* * We allocated a dummy extent, just to use extent buffer accessors. * There will be unused space after BTRFS_SUPER_INFO_SIZE, but * that's fine, we will not go beyond system chunk array anyway. */ sb = alloc_dummy_extent_buffer(fs_info, BTRFS_SUPER_INFO_OFFSET); if (!sb) return -ENOMEM; set_extent_buffer_uptodate(sb); write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); array_size = btrfs_super_sys_array_size(super_copy); array_ptr = super_copy->sys_chunk_array; sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array); cur_offset = 0; while (cur_offset < array_size) { disk_key = (struct btrfs_disk_key *)array_ptr; len = sizeof(*disk_key); if (cur_offset + len > array_size) goto out_short_read; btrfs_disk_key_to_cpu(&key, disk_key); array_ptr += len; sb_array_offset += len; cur_offset += len; if (key.type != BTRFS_CHUNK_ITEM_KEY) { btrfs_err(fs_info, "unexpected item type %u in sys_array at offset %u", (u32)key.type, cur_offset); ret = -EIO; break; } chunk = (struct btrfs_chunk *)sb_array_offset; /* * At least one btrfs_chunk with one stripe must be present, * exact stripe count check comes afterwards */ len = btrfs_chunk_item_size(1); if (cur_offset + len > array_size) goto out_short_read; num_stripes = btrfs_chunk_num_stripes(sb, chunk); if (!num_stripes) { btrfs_err(fs_info, "invalid number of stripes %u in sys_array at offset %u", num_stripes, cur_offset); ret = -EIO; break; } type = btrfs_chunk_type(sb, chunk); if ((type & BTRFS_BLOCK_GROUP_SYSTEM) == 0) { btrfs_err(fs_info, "invalid chunk type %llu in sys_array at offset %u", type, cur_offset); ret = -EIO; break; } len = btrfs_chunk_item_size(num_stripes); if (cur_offset + len > array_size) goto out_short_read; ret = read_one_chunk(&key, sb, chunk); if (ret) break; array_ptr += len; sb_array_offset += len; cur_offset += len; } clear_extent_buffer_uptodate(sb); free_extent_buffer_stale(sb); return ret; out_short_read: btrfs_err(fs_info, "sys_array too short to read %u bytes at offset %u", len, cur_offset); clear_extent_buffer_uptodate(sb); free_extent_buffer_stale(sb); return -EIO; } /* * Check if all chunks in the fs are OK for read-write degraded mount * * If the @failing_dev is specified, it's accounted as missing. * * Return true if all chunks meet the minimal RW mount requirements. * Return false if any chunk doesn't meet the minimal RW mount requirements. */ bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info, struct btrfs_device *failing_dev) { struct btrfs_chunk_map *map; u64 next_start; bool ret = true; map = btrfs_find_chunk_map(fs_info, 0, U64_MAX); /* No chunk at all? Return false anyway */ if (!map) { ret = false; goto out; } while (map) { int missing = 0; int max_tolerated; int i; max_tolerated = btrfs_get_num_tolerated_disk_barrier_failures( map->type); for (i = 0; i < map->num_stripes; i++) { struct btrfs_device *dev = map->stripes[i].dev; if (!dev || !dev->bdev || test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) || dev->last_flush_error) missing++; else if (failing_dev && failing_dev == dev) missing++; } if (missing > max_tolerated) { if (!failing_dev) btrfs_warn(fs_info, "chunk %llu missing %d devices, max tolerance is %d for writable mount", map->start, missing, max_tolerated); btrfs_free_chunk_map(map); ret = false; goto out; } next_start = map->start + map->chunk_len; btrfs_free_chunk_map(map); map = btrfs_find_chunk_map(fs_info, next_start, U64_MAX - next_start); } out: return ret; } static void readahead_tree_node_children(struct extent_buffer *node) { int i; const int nr_items = btrfs_header_nritems(node); for (i = 0; i < nr_items; i++) btrfs_readahead_node_child(node, i); } int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info) { struct btrfs_root *root = fs_info->chunk_root; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key; struct btrfs_key found_key; int ret; int slot; int iter_ret = 0; u64 total_dev = 0; u64 last_ra_node = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; /* * uuid_mutex is needed only if we are mounting a sprout FS * otherwise we don't need it. */ mutex_lock(&uuid_mutex); /* * It is possible for mount and umount to race in such a way that * we execute this code path, but open_fs_devices failed to clear * total_rw_bytes. We certainly want it cleared before reading the * device items, so clear it here. */ fs_info->fs_devices->total_rw_bytes = 0; /* * Lockdep complains about possible circular locking dependency between * a disk's open_mutex (struct gendisk.open_mutex), the rw semaphores * used for freeze procection of a fs (struct super_block.s_writers), * which we take when starting a transaction, and extent buffers of the * chunk tree if we call read_one_dev() while holding a lock on an * extent buffer of the chunk tree. Since we are mounting the filesystem * and at this point there can't be any concurrent task modifying the * chunk tree, to keep it simple, just skip locking on the chunk tree. */ ASSERT(!test_bit(BTRFS_FS_OPEN, &fs_info->flags)); path->skip_locking = 1; /* * Read all device items, and then all the chunk items. All * device items are found before any chunk item (their object id * is smaller than the lowest possible object id for a chunk * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID). */ key.objectid = BTRFS_DEV_ITEMS_OBJECTID; key.offset = 0; key.type = 0; btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) { struct extent_buffer *node = path->nodes[1]; leaf = path->nodes[0]; slot = path->slots[0]; if (node) { if (last_ra_node != node->start) { readahead_tree_node_children(node); last_ra_node = node->start; } } if (found_key.type == BTRFS_DEV_ITEM_KEY) { struct btrfs_dev_item *dev_item; dev_item = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item); ret = read_one_dev(leaf, dev_item); if (ret) goto error; total_dev++; } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { struct btrfs_chunk *chunk; /* * We are only called at mount time, so no need to take * fs_info->chunk_mutex. Plus, to avoid lockdep warnings, * we always lock first fs_info->chunk_mutex before * acquiring any locks on the chunk tree. This is a * requirement for chunk allocation, see the comment on * top of btrfs_chunk_alloc() for details. */ chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); ret = read_one_chunk(&found_key, leaf, chunk); if (ret) goto error; } } /* Catch error found during iteration */ if (iter_ret < 0) { ret = iter_ret; goto error; } /* * After loading chunk tree, we've got all device information, * do another round of validation checks. */ if (total_dev != fs_info->fs_devices->total_devices) { btrfs_warn(fs_info, "super block num_devices %llu mismatch with DEV_ITEM count %llu, will be repaired on next transaction commit", btrfs_super_num_devices(fs_info->super_copy), total_dev); fs_info->fs_devices->total_devices = total_dev; btrfs_set_super_num_devices(fs_info->super_copy, total_dev); } if (btrfs_super_total_bytes(fs_info->super_copy) < fs_info->fs_devices->total_rw_bytes) { btrfs_err(fs_info, "super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu", btrfs_super_total_bytes(fs_info->super_copy), fs_info->fs_devices->total_rw_bytes); ret = -EINVAL; goto error; } ret = 0; error: mutex_unlock(&uuid_mutex); btrfs_free_path(path); return ret; } int btrfs_init_devices_late(struct btrfs_fs_info *fs_info) { struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs; struct btrfs_device *device; int ret = 0; fs_devices->fs_info = fs_info; mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry(device, &fs_devices->devices, dev_list) device->fs_info = fs_info; list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) { list_for_each_entry(device, &seed_devs->devices, dev_list) { device->fs_info = fs_info; ret = btrfs_get_dev_zone_info(device, false); if (ret) break; } seed_devs->fs_info = fs_info; } mutex_unlock(&fs_devices->device_list_mutex); return ret; } static u64 btrfs_dev_stats_value(const struct extent_buffer *eb, const struct btrfs_dev_stats_item *ptr, int index) { u64 val; read_extent_buffer(eb, &val, offsetof(struct btrfs_dev_stats_item, values) + ((unsigned long)ptr) + (index * sizeof(u64)), sizeof(val)); return val; } static void btrfs_set_dev_stats_value(struct extent_buffer *eb, struct btrfs_dev_stats_item *ptr, int index, u64 val) { write_extent_buffer(eb, &val, offsetof(struct btrfs_dev_stats_item, values) + ((unsigned long)ptr) + (index * sizeof(u64)), sizeof(val)); } static int btrfs_device_init_dev_stats(struct btrfs_device *device, struct btrfs_path *path) { struct btrfs_dev_stats_item *ptr; struct extent_buffer *eb; struct btrfs_key key; int item_size; int i, ret, slot; if (!device->fs_info->dev_root) return 0; key.objectid = BTRFS_DEV_STATS_OBJECTID; key.type = BTRFS_PERSISTENT_ITEM_KEY; key.offset = device->devid; ret = btrfs_search_slot(NULL, device->fs_info->dev_root, &key, path, 0, 0); if (ret) { for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) btrfs_dev_stat_set(device, i, 0); device->dev_stats_valid = 1; btrfs_release_path(path); return ret < 0 ? ret : 0; } slot = path->slots[0]; eb = path->nodes[0]; item_size = btrfs_item_size(eb, slot); ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_stats_item); for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { if (item_size >= (1 + i) * sizeof(__le64)) btrfs_dev_stat_set(device, i, btrfs_dev_stats_value(eb, ptr, i)); else btrfs_dev_stat_set(device, i, 0); } device->dev_stats_valid = 1; btrfs_dev_stat_print_on_load(device); btrfs_release_path(path); return 0; } int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) { struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs; struct btrfs_device *device; struct btrfs_path *path = NULL; int ret = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry(device, &fs_devices->devices, dev_list) { ret = btrfs_device_init_dev_stats(device, path); if (ret) goto out; } list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) { list_for_each_entry(device, &seed_devs->devices, dev_list) { ret = btrfs_device_init_dev_stats(device, path); if (ret) goto out; } } out: mutex_unlock(&fs_devices->device_list_mutex); btrfs_free_path(path); return ret; } static int update_dev_stat_item(struct btrfs_trans_handle *trans, struct btrfs_device *device) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_root *dev_root = fs_info->dev_root; struct btrfs_path *path; struct btrfs_key key; struct extent_buffer *eb; struct btrfs_dev_stats_item *ptr; int ret; int i; key.objectid = BTRFS_DEV_STATS_OBJECTID; key.type = BTRFS_PERSISTENT_ITEM_KEY; key.offset = device->devid; path = btrfs_alloc_path(); if (!path) return -ENOMEM; ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); if (ret < 0) { btrfs_warn_in_rcu(fs_info, "error %d while searching for dev_stats item for device %s", ret, btrfs_dev_name(device)); goto out; } if (ret == 0 && btrfs_item_size(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { /* need to delete old one and insert a new one */ ret = btrfs_del_item(trans, dev_root, path); if (ret != 0) { btrfs_warn_in_rcu(fs_info, "delete too small dev_stats item for device %s failed %d", btrfs_dev_name(device), ret); goto out; } ret = 1; } if (ret == 1) { /* need to insert a new item */ btrfs_release_path(path); ret = btrfs_insert_empty_item(trans, dev_root, path, &key, sizeof(*ptr)); if (ret < 0) { btrfs_warn_in_rcu(fs_info, "insert dev_stats item for device %s failed %d", btrfs_dev_name(device), ret); goto out; } } eb = path->nodes[0]; ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) btrfs_set_dev_stats_value(eb, ptr, i, btrfs_dev_stat_read(device, i)); btrfs_mark_buffer_dirty(trans, eb); out: btrfs_free_path(path); return ret; } /* * called from commit_transaction. Writes all changed device stats to disk. */ int btrfs_run_dev_stats(struct btrfs_trans_handle *trans) { struct btrfs_fs_info *fs_info = trans->fs_info; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; struct btrfs_device *device; int stats_cnt; int ret = 0; mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry(device, &fs_devices->devices, dev_list) { stats_cnt = atomic_read(&device->dev_stats_ccnt); if (!device->dev_stats_valid || stats_cnt == 0) continue; /* * There is a LOAD-LOAD control dependency between the value of * dev_stats_ccnt and updating the on-disk values which requires * reading the in-memory counters. Such control dependencies * require explicit read memory barriers. * * This memory barriers pairs with smp_mb__before_atomic in * btrfs_dev_stat_inc/btrfs_dev_stat_set and with the full * barrier implied by atomic_xchg in * btrfs_dev_stats_read_and_reset */ smp_rmb(); ret = update_dev_stat_item(trans, device); if (!ret) atomic_sub(stats_cnt, &device->dev_stats_ccnt); } mutex_unlock(&fs_devices->device_list_mutex); return ret; } void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) { btrfs_dev_stat_inc(dev, index); if (!dev->dev_stats_valid) return; btrfs_err_rl_in_rcu(dev->fs_info, "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u", btrfs_dev_name(dev), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); } static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) { int i; for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) if (btrfs_dev_stat_read(dev, i) != 0) break; if (i == BTRFS_DEV_STAT_VALUES_MAX) return; /* all values == 0, suppress message */ btrfs_info_in_rcu(dev->fs_info, "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u", btrfs_dev_name(dev), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); } int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info, struct btrfs_ioctl_get_dev_stats *stats) { BTRFS_DEV_LOOKUP_ARGS(args); struct btrfs_device *dev; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; int i; mutex_lock(&fs_devices->device_list_mutex); args.devid = stats->devid; dev = btrfs_find_device(fs_info->fs_devices, &args); mutex_unlock(&fs_devices->device_list_mutex); if (!dev) { btrfs_warn(fs_info, "get dev_stats failed, device not found"); return -ENODEV; } else if (!dev->dev_stats_valid) { btrfs_warn(fs_info, "get dev_stats failed, not yet valid"); return -ENODEV; } else if (stats->flags & BTRFS_DEV_STATS_RESET) { for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { if (stats->nr_items > i) stats->values[i] = btrfs_dev_stat_read_and_reset(dev, i); else btrfs_dev_stat_set(dev, i, 0); } btrfs_info(fs_info, "device stats zeroed by %s (%d)", current->comm, task_pid_nr(current)); } else { for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) if (stats->nr_items > i) stats->values[i] = btrfs_dev_stat_read(dev, i); } if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; return 0; } /* * Update the size and bytes used for each device where it changed. This is * delayed since we would otherwise get errors while writing out the * superblocks. * * Must be invoked during transaction commit. */ void btrfs_commit_device_sizes(struct btrfs_transaction *trans) { struct btrfs_device *curr, *next; ASSERT(trans->state == TRANS_STATE_COMMIT_DOING); if (list_empty(&trans->dev_update_list)) return; /* * We don't need the device_list_mutex here. This list is owned by the * transaction and the transaction must complete before the device is * released. */ mutex_lock(&trans->fs_info->chunk_mutex); list_for_each_entry_safe(curr, next, &trans->dev_update_list, post_commit_list) { list_del_init(&curr->post_commit_list); curr->commit_total_bytes = curr->disk_total_bytes; curr->commit_bytes_used = curr->bytes_used; } mutex_unlock(&trans->fs_info->chunk_mutex); } /* * Multiplicity factor for simple profiles: DUP, RAID1-like and RAID10. */ int btrfs_bg_type_to_factor(u64 flags) { const int index = btrfs_bg_flags_to_raid_index(flags); return btrfs_raid_array[index].ncopies; } static int verify_one_dev_extent(struct btrfs_fs_info *fs_info, u64 chunk_offset, u64 devid, u64 physical_offset, u64 physical_len) { struct btrfs_dev_lookup_args args = { .devid = devid }; struct btrfs_chunk_map *map; struct btrfs_device *dev; u64 stripe_len; bool found = false; int ret = 0; int i; map = btrfs_find_chunk_map(fs_info, chunk_offset, 1); if (!map) { btrfs_err(fs_info, "dev extent physical offset %llu on devid %llu doesn't have corresponding chunk", physical_offset, devid); ret = -EUCLEAN; goto out; } stripe_len = btrfs_calc_stripe_length(map); if (physical_len != stripe_len) { btrfs_err(fs_info, "dev extent physical offset %llu on devid %llu length doesn't match chunk %llu, have %llu expect %llu", physical_offset, devid, map->start, physical_len, stripe_len); ret = -EUCLEAN; goto out; } /* * Very old mkfs.btrfs (before v4.1) will not respect the reserved * space. Although kernel can handle it without problem, better to warn * the users. */ if (physical_offset < BTRFS_DEVICE_RANGE_RESERVED) btrfs_warn(fs_info, "devid %llu physical %llu len %llu inside the reserved space", devid, physical_offset, physical_len); for (i = 0; i < map->num_stripes; i++) { if (map->stripes[i].dev->devid == devid && map->stripes[i].physical == physical_offset) { found = true; if (map->verified_stripes >= map->num_stripes) { btrfs_err(fs_info, "too many dev extents for chunk %llu found", map->start); ret = -EUCLEAN; goto out; } map->verified_stripes++; break; } } if (!found) { btrfs_err(fs_info, "dev extent physical offset %llu devid %llu has no corresponding chunk", physical_offset, devid); ret = -EUCLEAN; } /* Make sure no dev extent is beyond device boundary */ dev = btrfs_find_device(fs_info->fs_devices, &args); if (!dev) { btrfs_err(fs_info, "failed to find devid %llu", devid); ret = -EUCLEAN; goto out; } if (physical_offset + physical_len > dev->disk_total_bytes) { btrfs_err(fs_info, "dev extent devid %llu physical offset %llu len %llu is beyond device boundary %llu", devid, physical_offset, physical_len, dev->disk_total_bytes); ret = -EUCLEAN; goto out; } if (dev->zone_info) { u64 zone_size = dev->zone_info->zone_size; if (!IS_ALIGNED(physical_offset, zone_size) || !IS_ALIGNED(physical_len, zone_size)) { btrfs_err(fs_info, "zoned: dev extent devid %llu physical offset %llu len %llu is not aligned to device zone", devid, physical_offset, physical_len); ret = -EUCLEAN; goto out; } } out: btrfs_free_chunk_map(map); return ret; } static int verify_chunk_dev_extent_mapping(struct btrfs_fs_info *fs_info) { struct rb_node *node; int ret = 0; read_lock(&fs_info->mapping_tree_lock); for (node = rb_first_cached(&fs_info->mapping_tree); node; node = rb_next(node)) { struct btrfs_chunk_map *map; map = rb_entry(node, struct btrfs_chunk_map, rb_node); if (map->num_stripes != map->verified_stripes) { btrfs_err(fs_info, "chunk %llu has missing dev extent, have %d expect %d", map->start, map->verified_stripes, map->num_stripes); ret = -EUCLEAN; goto out; } } out: read_unlock(&fs_info->mapping_tree_lock); return ret; } /* * Ensure that all dev extents are mapped to correct chunk, otherwise * later chunk allocation/free would cause unexpected behavior. * * NOTE: This will iterate through the whole device tree, which should be of * the same size level as the chunk tree. This slightly increases mount time. */ int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info) { struct btrfs_path *path; struct btrfs_root *root = fs_info->dev_root; struct btrfs_key key; u64 prev_devid = 0; u64 prev_dev_ext_end = 0; int ret = 0; /* * We don't have a dev_root because we mounted with ignorebadroots and * failed to load the root, so we want to skip the verification in this * case for sure. * * However if the dev root is fine, but the tree itself is corrupted * we'd still fail to mount. This verification is only to make sure * writes can happen safely, so instead just bypass this check * completely in the case of IGNOREBADROOTS. */ if (btrfs_test_opt(fs_info, IGNOREBADROOTS)) return 0; key.objectid = 1; key.type = BTRFS_DEV_EXTENT_KEY; key.offset = 0; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = READA_FORWARD; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { ret = btrfs_next_leaf(root, path); if (ret < 0) goto out; /* No dev extents at all? Not good */ if (ret > 0) { ret = -EUCLEAN; goto out; } } while (1) { struct extent_buffer *leaf = path->nodes[0]; struct btrfs_dev_extent *dext; int slot = path->slots[0]; u64 chunk_offset; u64 physical_offset; u64 physical_len; u64 devid; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.type != BTRFS_DEV_EXTENT_KEY) break; devid = key.objectid; physical_offset = key.offset; dext = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent); chunk_offset = btrfs_dev_extent_chunk_offset(leaf, dext); physical_len = btrfs_dev_extent_length(leaf, dext); /* Check if this dev extent overlaps with the previous one */ if (devid == prev_devid && physical_offset < prev_dev_ext_end) { btrfs_err(fs_info, "dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu", devid, physical_offset, prev_dev_ext_end); ret = -EUCLEAN; goto out; } ret = verify_one_dev_extent(fs_info, chunk_offset, devid, physical_offset, physical_len); if (ret < 0) goto out; prev_devid = devid; prev_dev_ext_end = physical_offset + physical_len; ret = btrfs_next_item(root, path); if (ret < 0) goto out; if (ret > 0) { ret = 0; break; } } /* Ensure all chunks have corresponding dev extents */ ret = verify_chunk_dev_extent_mapping(fs_info); out: btrfs_free_path(path); return ret; } /* * Check whether the given block group or device is pinned by any inode being * used as a swapfile. */ bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr) { struct btrfs_swapfile_pin *sp; struct rb_node *node; spin_lock(&fs_info->swapfile_pins_lock); node = fs_info->swapfile_pins.rb_node; while (node) { sp = rb_entry(node, struct btrfs_swapfile_pin, node); if (ptr < sp->ptr) node = node->rb_left; else if (ptr > sp->ptr) node = node->rb_right; else break; } spin_unlock(&fs_info->swapfile_pins_lock); return node != NULL; } static int relocating_repair_kthread(void *data) { struct btrfs_block_group *cache = data; struct btrfs_fs_info *fs_info = cache->fs_info; u64 target; int ret = 0; target = cache->start; btrfs_put_block_group(cache); sb_start_write(fs_info->sb); if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) { btrfs_info(fs_info, "zoned: skip relocating block group %llu to repair: EBUSY", target); sb_end_write(fs_info->sb); return -EBUSY; } mutex_lock(&fs_info->reclaim_bgs_lock); /* Ensure block group still exists */ cache = btrfs_lookup_block_group(fs_info, target); if (!cache) goto out; if (!test_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags)) goto out; ret = btrfs_may_alloc_data_chunk(fs_info, target); if (ret < 0) goto out; btrfs_info(fs_info, "zoned: relocating block group %llu to repair IO failure", target); ret = btrfs_relocate_chunk(fs_info, target); out: if (cache) btrfs_put_block_group(cache); mutex_unlock(&fs_info->reclaim_bgs_lock); btrfs_exclop_finish(fs_info); sb_end_write(fs_info->sb); return ret; } bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical) { struct btrfs_block_group *cache; if (!btrfs_is_zoned(fs_info)) return false; /* Do not attempt to repair in degraded state */ if (btrfs_test_opt(fs_info, DEGRADED)) return true; cache = btrfs_lookup_block_group(fs_info, logical); if (!cache) return true; if (test_and_set_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags)) { btrfs_put_block_group(cache); return true; } kthread_run(relocating_repair_kthread, cache, "btrfs-relocating-repair"); return true; } static void map_raid56_repair_block(struct btrfs_io_context *bioc, struct btrfs_io_stripe *smap, u64 logical) { int data_stripes = nr_bioc_data_stripes(bioc); int i; for (i = 0; i < data_stripes; i++) { u64 stripe_start = bioc->full_stripe_logical + btrfs_stripe_nr_to_offset(i); if (logical >= stripe_start && logical < stripe_start + BTRFS_STRIPE_LEN) break; } ASSERT(i < data_stripes); smap->dev = bioc->stripes[i].dev; smap->physical = bioc->stripes[i].physical + ((logical - bioc->full_stripe_logical) & BTRFS_STRIPE_LEN_MASK); } /* * Map a repair write into a single device. * * A repair write is triggered by read time repair or scrub, which would only * update the contents of a single device. * Not update any other mirrors nor go through RMW path. * * Callers should ensure: * * - Call btrfs_bio_counter_inc_blocked() first * - The range does not cross stripe boundary * - Has a valid @mirror_num passed in. */ int btrfs_map_repair_block(struct btrfs_fs_info *fs_info, struct btrfs_io_stripe *smap, u64 logical, u32 length, int mirror_num) { struct btrfs_io_context *bioc = NULL; u64 map_length = length; int mirror_ret = mirror_num; int ret; ASSERT(mirror_num > 0); ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, &map_length, &bioc, smap, &mirror_ret); if (ret < 0) return ret; /* The map range should not cross stripe boundary. */ ASSERT(map_length >= length); /* Already mapped to single stripe. */ if (!bioc) goto out; /* Map the RAID56 multi-stripe writes to a single one. */ if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) { map_raid56_repair_block(bioc, smap, logical); goto out; } ASSERT(mirror_num <= bioc->num_stripes); smap->dev = bioc->stripes[mirror_num - 1].dev; smap->physical = bioc->stripes[mirror_num - 1].physical; out: btrfs_put_bioc(bioc); ASSERT(smap->dev); return 0; }