diff options
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/loop.c | 128 | ||||
| -rw-r--r-- | drivers/block/n64cart.c | 2 | ||||
| -rw-r--r-- | drivers/block/nbd.c | 16 | ||||
| -rw-r--r-- | drivers/block/paride/pd.c | 2 | ||||
| -rw-r--r-- | drivers/block/rbd.c | 33 | ||||
| -rw-r--r-- | drivers/block/xen-blkfront.c | 224 |
6 files changed, 150 insertions, 255 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index f37b9e3d833c..f0cdff0c5fbf 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -88,6 +88,47 @@ static DEFINE_IDR(loop_index_idr); static DEFINE_MUTEX(loop_ctl_mutex); +static DEFINE_MUTEX(loop_validate_mutex); + +/** + * loop_global_lock_killable() - take locks for safe loop_validate_file() test + * + * @lo: struct loop_device + * @global: true if @lo is about to bind another "struct loop_device", false otherwise + * + * Returns 0 on success, -EINTR otherwise. + * + * Since loop_validate_file() traverses on other "struct loop_device" if + * is_loop_device() is true, we need a global lock for serializing concurrent + * loop_configure()/loop_change_fd()/__loop_clr_fd() calls. + */ +static int loop_global_lock_killable(struct loop_device *lo, bool global) +{ + int err; + + if (global) { + err = mutex_lock_killable(&loop_validate_mutex); + if (err) + return err; + } + err = mutex_lock_killable(&lo->lo_mutex); + if (err && global) + mutex_unlock(&loop_validate_mutex); + return err; +} + +/** + * loop_global_unlock() - release locks taken by loop_global_lock_killable() + * + * @lo: struct loop_device + * @global: true if @lo was about to bind another "struct loop_device", false otherwise + */ +static void loop_global_unlock(struct loop_device *lo, bool global) +{ + mutex_unlock(&lo->lo_mutex); + if (global) + mutex_unlock(&loop_validate_mutex); +} static int max_part; static int part_shift; @@ -672,13 +713,15 @@ static int loop_validate_file(struct file *file, struct block_device *bdev) while (is_loop_device(f)) { struct loop_device *l; + lockdep_assert_held(&loop_validate_mutex); if (f->f_mapping->host->i_rdev == bdev->bd_dev) return -EBADF; l = I_BDEV(f->f_mapping->host)->bd_disk->private_data; - if (l->lo_state != Lo_bound) { + if (l->lo_state != Lo_bound) return -EINVAL; - } + /* Order wrt setting lo->lo_backing_file in loop_configure(). */ + rmb(); f = l->lo_backing_file; } if (!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode)) @@ -697,13 +740,18 @@ static int loop_validate_file(struct file *file, struct block_device *bdev) static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, unsigned int arg) { - struct file *file = NULL, *old_file; - int error; - bool partscan; + struct file *file = fget(arg); + struct file *old_file; + int error; + bool partscan; + bool is_loop; - error = mutex_lock_killable(&lo->lo_mutex); + if (!file) + return -EBADF; + is_loop = is_loop_device(file); + error = loop_global_lock_killable(lo, is_loop); if (error) - return error; + goto out_putf; error = -ENXIO; if (lo->lo_state != Lo_bound) goto out_err; @@ -713,11 +761,6 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, if (!(lo->lo_flags & LO_FLAGS_READ_ONLY)) goto out_err; - error = -EBADF; - file = fget(arg); - if (!file) - goto out_err; - error = loop_validate_file(file, bdev); if (error) goto out_err; @@ -740,7 +783,16 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, loop_update_dio(lo); blk_mq_unfreeze_queue(lo->lo_queue); partscan = lo->lo_flags & LO_FLAGS_PARTSCAN; - mutex_unlock(&lo->lo_mutex); + loop_global_unlock(lo, is_loop); + + /* + * Flush loop_validate_file() before fput(), for l->lo_backing_file + * might be pointing at old_file which might be the last reference. + */ + if (!is_loop) { + mutex_lock(&loop_validate_mutex); + mutex_unlock(&loop_validate_mutex); + } /* * We must drop file reference outside of lo_mutex as dropping * the file ref can take open_mutex which creates circular locking @@ -752,9 +804,9 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, return 0; out_err: - mutex_unlock(&lo->lo_mutex); - if (file) - fput(file); + loop_global_unlock(lo, is_loop); +out_putf: + fput(file); return error; } @@ -1136,22 +1188,22 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, struct block_device *bdev, const struct loop_config *config) { - struct file *file; - struct inode *inode; + struct file *file = fget(config->fd); + struct inode *inode; struct address_space *mapping; - int error; - loff_t size; - bool partscan; - unsigned short bsize; + int error; + loff_t size; + bool partscan; + unsigned short bsize; + bool is_loop; + + if (!file) + return -EBADF; + is_loop = is_loop_device(file); /* This is safe, since we have a reference from open(). */ __module_get(THIS_MODULE); - error = -EBADF; - file = fget(config->fd); - if (!file) - goto out; - /* * If we don't hold exclusive handle for the device, upgrade to it * here to avoid changing device under exclusive owner. @@ -1162,7 +1214,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, goto out_putf; } - error = mutex_lock_killable(&lo->lo_mutex); + error = loop_global_lock_killable(lo, is_loop); if (error) goto out_bdev; @@ -1242,6 +1294,9 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, size = get_loop_size(lo, file); loop_set_size(lo, size); + /* Order wrt reading lo_state in loop_validate_file(). */ + wmb(); + lo->lo_state = Lo_bound; if (part_shift) lo->lo_flags |= LO_FLAGS_PARTSCAN; @@ -1253,7 +1308,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, * put /dev/loopXX inode. Later in __loop_clr_fd() we bdput(bdev). */ bdgrab(bdev); - mutex_unlock(&lo->lo_mutex); + loop_global_unlock(lo, is_loop); if (partscan) loop_reread_partitions(lo); if (!(mode & FMODE_EXCL)) @@ -1261,13 +1316,12 @@ static int loop_configure(struct loop_device *lo, fmode_t mode, return 0; out_unlock: - mutex_unlock(&lo->lo_mutex); + loop_global_unlock(lo, is_loop); out_bdev: if (!(mode & FMODE_EXCL)) bd_abort_claiming(bdev, loop_configure); out_putf: fput(file); -out: /* This is safe: open() is still holding a reference. */ module_put(THIS_MODULE); return error; @@ -1283,6 +1337,18 @@ static int __loop_clr_fd(struct loop_device *lo, bool release) int lo_number; struct loop_worker *pos, *worker; + /* + * Flush loop_configure() and loop_change_fd(). It is acceptable for + * loop_validate_file() to succeed, for actual clear operation has not + * started yet. + */ + mutex_lock(&loop_validate_mutex); + mutex_unlock(&loop_validate_mutex); + /* + * loop_validate_file() now fails because l->lo_state != Lo_bound + * became visible. + */ + mutex_lock(&lo->lo_mutex); if (WARN_ON_ONCE(lo->lo_state != Lo_rundown)) { err = -ENXIO; diff --git a/drivers/block/n64cart.c b/drivers/block/n64cart.c index 7b4dd10af9ec..c84be0028f63 100644 --- a/drivers/block/n64cart.c +++ b/drivers/block/n64cart.c @@ -74,7 +74,7 @@ static bool n64cart_do_bvec(struct device *dev, struct bio_vec *bv, u32 pos) n64cart_wait_dma(); - n64cart_write_reg(PI_DRAM_REG, dma_addr + bv->bv_offset); + n64cart_write_reg(PI_DRAM_REG, dma_addr); n64cart_write_reg(PI_CART_REG, (bstart | CART_DOMAIN) & CART_MAX); n64cart_write_reg(PI_WRITE_REG, bv->bv_len - 1); diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index b7d663736d35..19f5d5a8b16a 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -239,8 +239,8 @@ static void nbd_dev_remove(struct nbd_device *nbd) if (disk) { del_gendisk(disk); - blk_mq_free_tag_set(&nbd->tag_set); blk_cleanup_disk(disk); + blk_mq_free_tag_set(&nbd->tag_set); } /* @@ -818,6 +818,10 @@ static bool nbd_clear_req(struct request *req, void *data, bool reserved) { struct nbd_cmd *cmd = blk_mq_rq_to_pdu(req); + /* don't abort one completed request */ + if (blk_mq_request_completed(req)) + return true; + mutex_lock(&cmd->lock); cmd->status = BLK_STS_IOERR; mutex_unlock(&cmd->lock); @@ -2004,15 +2008,19 @@ static void nbd_disconnect_and_put(struct nbd_device *nbd) { mutex_lock(&nbd->config_lock); nbd_disconnect(nbd); - nbd_clear_sock(nbd); - mutex_unlock(&nbd->config_lock); + sock_shutdown(nbd); /* * Make sure recv thread has finished, so it does not drop the last * config ref and try to destroy the workqueue from inside the work - * queue. + * queue. And this also ensure that we can safely call nbd_clear_que() + * to cancel the inflight I/Os. */ if (nbd->recv_workq) flush_workqueue(nbd->recv_workq); + nbd_clear_que(nbd); + nbd->task_setup = NULL; + mutex_unlock(&nbd->config_lock); + if (test_and_clear_bit(NBD_RT_HAS_CONFIG_REF, &nbd->config->runtime_flags)) nbd_config_put(nbd); diff --git a/drivers/block/paride/pd.c b/drivers/block/paride/pd.c index 3b2b8e872beb..9b3298926356 100644 --- a/drivers/block/paride/pd.c +++ b/drivers/block/paride/pd.c @@ -1014,8 +1014,8 @@ static void __exit pd_exit(void) if (p) { disk->gd = NULL; del_gendisk(p); - blk_mq_free_tag_set(&disk->tag_set); blk_cleanup_disk(p); + blk_mq_free_tag_set(&disk->tag_set); pi_release(disk->pi); } } diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 531d390902dd..90b947c96402 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -4100,8 +4100,6 @@ again: static bool rbd_quiesce_lock(struct rbd_device *rbd_dev) { - bool need_wait; - dout("%s rbd_dev %p\n", __func__, rbd_dev); lockdep_assert_held_write(&rbd_dev->lock_rwsem); @@ -4113,11 +4111,11 @@ static bool rbd_quiesce_lock(struct rbd_device *rbd_dev) */ rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING; rbd_assert(!completion_done(&rbd_dev->releasing_wait)); - need_wait = !list_empty(&rbd_dev->running_list); - downgrade_write(&rbd_dev->lock_rwsem); - if (need_wait) - wait_for_completion(&rbd_dev->releasing_wait); - up_read(&rbd_dev->lock_rwsem); + if (list_empty(&rbd_dev->running_list)) + return true; + + up_write(&rbd_dev->lock_rwsem); + wait_for_completion(&rbd_dev->releasing_wait); down_write(&rbd_dev->lock_rwsem); if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING) @@ -4203,15 +4201,11 @@ static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v, if (!rbd_cid_equal(&cid, &rbd_empty_cid)) { down_write(&rbd_dev->lock_rwsem); if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) { - /* - * we already know that the remote client is - * the owner - */ - up_write(&rbd_dev->lock_rwsem); - return; + dout("%s rbd_dev %p cid %llu-%llu == owner_cid\n", + __func__, rbd_dev, cid.gid, cid.handle); + } else { + rbd_set_owner_cid(rbd_dev, &cid); } - - rbd_set_owner_cid(rbd_dev, &cid); downgrade_write(&rbd_dev->lock_rwsem); } else { down_read(&rbd_dev->lock_rwsem); @@ -4236,14 +4230,12 @@ static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v, if (!rbd_cid_equal(&cid, &rbd_empty_cid)) { down_write(&rbd_dev->lock_rwsem); if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) { - dout("%s rbd_dev %p unexpected owner, cid %llu-%llu != owner_cid %llu-%llu\n", + dout("%s rbd_dev %p cid %llu-%llu != owner_cid %llu-%llu\n", __func__, rbd_dev, cid.gid, cid.handle, rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle); - up_write(&rbd_dev->lock_rwsem); - return; + } else { + rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); } - - rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); downgrade_write(&rbd_dev->lock_rwsem); } else { down_read(&rbd_dev->lock_rwsem); @@ -4951,6 +4943,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev) disk->minors = RBD_MINORS_PER_MAJOR; } disk->fops = &rbd_bd_ops; + disk->private_data = rbd_dev; blk_queue_flag_set(QUEUE_FLAG_NONROT, q); /* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */ diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 8d49f8fa98bb..d83fee21f6c5 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -502,34 +502,21 @@ static int blkif_getgeo(struct block_device *bd, struct hd_geometry *hg) static int blkif_ioctl(struct block_device *bdev, fmode_t mode, unsigned command, unsigned long argument) { - struct blkfront_info *info = bdev->bd_disk->private_data; int i; - dev_dbg(&info->xbdev->dev, "command: 0x%x, argument: 0x%lx\n", - command, (long)argument); - switch (command) { case CDROMMULTISESSION: - dev_dbg(&info->xbdev->dev, "FIXME: support multisession CDs later\n"); for (i = 0; i < sizeof(struct cdrom_multisession); i++) if (put_user(0, (char __user *)(argument + i))) return -EFAULT; return 0; - - case CDROM_GET_CAPABILITY: { - struct gendisk *gd = info->gd; - if (gd->flags & GENHD_FL_CD) + case CDROM_GET_CAPABILITY: + if (bdev->bd_disk->flags & GENHD_FL_CD) return 0; return -EINVAL; - } - default: - /*printk(KERN_ALERT "ioctl %08x not supported by Xen blkdev\n", - command);*/ - return -EINVAL; /* same return as native Linux */ + return -EINVAL; } - - return 0; } static unsigned long blkif_ring_get_request(struct blkfront_ring_info *rinfo, @@ -1177,36 +1164,6 @@ out_release_minors: return err; } -static void xlvbd_release_gendisk(struct blkfront_info *info) -{ - unsigned int minor, nr_minors, i; - struct blkfront_ring_info *rinfo; - - if (info->rq == NULL) - return; - - /* No more blkif_request(). */ - blk_mq_stop_hw_queues(info->rq); - - for_each_rinfo(info, rinfo, i) { - /* No more gnttab callback work. */ - gnttab_cancel_free_callback(&rinfo->callback); - - /* Flush gnttab callback work. Must be done with no locks held. */ - flush_work(&rinfo->work); - } - - del_gendisk(info->gd); - - minor = info->gd->first_minor; - nr_minors = info->gd->minors; - xlbd_release_minors(minor, nr_minors); - - blk_cleanup_disk(info->gd); - info->gd = NULL; - blk_mq_free_tag_set(&info->tag_set); -} - /* Already hold rinfo->ring_lock. */ static inline void kick_pending_request_queues_locked(struct blkfront_ring_info *rinfo) { @@ -1756,12 +1713,6 @@ abort_transaction: return err; } -static void free_info(struct blkfront_info *info) -{ - list_del(&info->info_list); - kfree(info); -} - /* Common code used when first setting up, and when resuming. */ static int talk_to_blkback(struct xenbus_device *dev, struct blkfront_info *info) @@ -1880,13 +1831,6 @@ again: xenbus_dev_fatal(dev, err, "%s", message); destroy_blkring: blkif_free(info, 0); - - mutex_lock(&blkfront_mutex); - free_info(info); - mutex_unlock(&blkfront_mutex); - - dev_set_drvdata(&dev->dev, NULL); - return err; } @@ -2126,38 +2070,26 @@ static int blkfront_resume(struct xenbus_device *dev) static void blkfront_closing(struct blkfront_info *info) { struct xenbus_device *xbdev = info->xbdev; - struct block_device *bdev = NULL; - - mutex_lock(&info->mutex); + struct blkfront_ring_info *rinfo; + unsigned int i; - if (xbdev->state == XenbusStateClosing) { - mutex_unlock(&info->mutex); + if (xbdev->state == XenbusStateClosing) return; - } - if (info->gd) - bdev = bdgrab(info->gd->part0); - - mutex_unlock(&info->mutex); - - if (!bdev) { - xenbus_frontend_closed(xbdev); - return; - } + /* No more blkif_request(). */ + blk_mq_stop_hw_queues(info->rq); + blk_set_queue_dying(info->rq); + set_capacity(info->gd, 0); - mutex_lock(&bdev->bd_disk->open_mutex); + for_each_rinfo(info, rinfo, i) { + /* No more gnttab callback work. */ + gnttab_cancel_free_callback(&rinfo->callback); - if (bdev->bd_openers) { - xenbus_dev_error(xbdev, -EBUSY, - "Device in use; refusing to close"); - xenbus_switch_state(xbdev, XenbusStateClosing); - } else { - xlvbd_release_gendisk(info); - xenbus_frontend_closed(xbdev); + /* Flush gnttab callback work. Must be done with no locks held. */ + flush_work(&rinfo->work); } - mutex_unlock(&bdev->bd_disk->open_mutex); - bdput(bdev); + xenbus_frontend_closed(xbdev); } static void blkfront_setup_discard(struct blkfront_info *info) @@ -2472,8 +2404,7 @@ static void blkback_changed(struct xenbus_device *dev, break; fallthrough; case XenbusStateClosing: - if (info) - blkfront_closing(info); + blkfront_closing(info); break; } } @@ -2481,56 +2412,21 @@ static void blkback_changed(struct xenbus_device *dev, static int blkfront_remove(struct xenbus_device *xbdev) { struct blkfront_info *info = dev_get_drvdata(&xbdev->dev); - struct block_device *bdev = NULL; - struct gendisk *disk; dev_dbg(&xbdev->dev, "%s removed", xbdev->nodename); - if (!info) - return 0; - - blkif_free(info, 0); - - mutex_lock(&info->mutex); - - disk = info->gd; - if (disk) - bdev = bdgrab(disk->part0); - - info->xbdev = NULL; - mutex_unlock(&info->mutex); - - if (!bdev) { - mutex_lock(&blkfront_mutex); - free_info(info); - mutex_unlock(&blkfront_mutex); - return 0; - } - - /* - * The xbdev was removed before we reached the Closed - * state. See if it's safe to remove the disk. If the bdev - * isn't closed yet, we let release take care of it. - */ - - mutex_lock(&disk->open_mutex); - info = disk->private_data; - - dev_warn(disk_to_dev(disk), - "%s was hot-unplugged, %d stale handles\n", - xbdev->nodename, bdev->bd_openers); + del_gendisk(info->gd); - if (info && !bdev->bd_openers) { - xlvbd_release_gendisk(info); - disk->private_data = NULL; - mutex_lock(&blkfront_mutex); - free_info(info); - mutex_unlock(&blkfront_mutex); - } + mutex_lock(&blkfront_mutex); + list_del(&info->info_list); + mutex_unlock(&blkfront_mutex); - mutex_unlock(&disk->open_mutex); - bdput(bdev); + blkif_free(info, 0); + xlbd_release_minors(info->gd->first_minor, info->gd->minors); + blk_cleanup_disk(info->gd); + blk_mq_free_tag_set(&info->tag_set); + kfree(info); return 0; } @@ -2541,77 +2437,9 @@ static int blkfront_is_ready(struct xenbus_device *dev) return info->is_ready && info->xbdev; } -static int blkif_open(struct block_device *bdev, fmode_t mode) -{ - struct gendisk *disk = bdev->bd_disk; - struct blkfront_info *info; - int err = 0; - - mutex_lock(&blkfront_mutex); - - info = disk->private_data; - if (!info) { - /* xbdev gone */ - err = -ERESTARTSYS; - goto out; - } - - mutex_lock(&info->mutex); - - if (!info->gd) - /* xbdev is closed */ - err = -ERESTARTSYS; - - mutex_unlock(&info->mutex); - -out: - mutex_unlock(&blkfront_mutex); - return err; -} - -static void blkif_release(struct gendisk *disk, fmode_t mode) -{ - struct blkfront_info *info = disk->private_data; - struct xenbus_device *xbdev; - - mutex_lock(&blkfront_mutex); - if (disk->part0->bd_openers) - goto out_mutex; - - /* - * Check if we have been instructed to close. We will have - * deferred this request, because the bdev was still open. - */ - - mutex_lock(&info->mutex); - xbdev = info->xbdev; - - if (xbdev && xbdev->state == XenbusStateClosing) { - /* pending switch to state closed */ - dev_info(disk_to_dev(disk), "releasing disk\n"); - xlvbd_release_gendisk(info); - xenbus_frontend_closed(info->xbdev); - } - - mutex_unlock(&info->mutex); - - if (!xbdev) { - /* sudden device removal */ - dev_info(disk_to_dev(disk), "releasing disk\n"); - xlvbd_release_gendisk(info); - disk->private_data = NULL; - free_info(info); - } - -out_mutex: - mutex_unlock(&blkfront_mutex); -} - static const struct block_device_operations xlvbd_block_fops = { .owner = THIS_MODULE, - .open = blkif_open, - .release = blkif_release, .getgeo = blkif_getgeo, .ioctl = blkif_ioctl, .compat_ioctl = blkdev_compat_ptr_ioctl, |