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2016-12-08md: separate flags for superblock changesShaohua Li1-2/+2
The mddev->flags are used for different purposes. There are a lot of places we check/change the flags without masking unrelated flags, we could check/change unrelated flags. These usage are most for superblock write, so spearate superblock related flags. This should make the code clearer and also fix real bugs. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-11-22md: Use REQ_FAILFAST_* on metadata writes where appropriateNeilBrown1-3/+12
This can only be supported on personalities which ensure that md_error() never causes an array to enter the 'failed' state. i.e. if marking a device Faulty would cause some data to be inaccessible, the device is status is left as non-Faulty. This is true for RAID1 and RAID10. If we get a failure writing metadata but the device doesn't fail, it must be the last device so we re-write without FAILFAST to improve chance of success. We also flag the device as LastDev so that future metadata updates don't waste time on failfast writes. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-11-18md/bitmap: add blktrace event for writes to the bitmapNeilBrown1-1/+10
We trace wheneven bitmap_unplug() finds that it needs to write to the bitmap, or when bitmap_daemon_work() find there is work to do. This makes it easier to correlate bitmap updates with data writes. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-11-07md/bitmap: Don't write bitmap while earlier writes might be in-flightNeilBrown1-5/+22
As we don't wait for writes to complete in bitmap_daemon_work, they could still be in-flight when bitmap_unplug writes again. Or when bitmap_daemon_work tries to write again. This can be confusing and could risk the wrong data being written last. So make sure we wait for old writes to complete before new writes start. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-11-07md/bitmap: change all printk() to pr_*()NeilBrown1-57/+50
Follow err/warn distinction introduced in md.c Join multi-part strings into single string. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-11-07md/bitmap: call bitmap_file_unmap once bitmap_storage_alloc returns -ENOMEMGuoqing Jiang1-1/+3
It is possible that bitmap_storage_alloc could return -ENOMEM, and some member inside store could be allocated such as filemap. To avoid memory leak, we need to call bitmap_file_unmap to free those members in the bitmap_resize. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21md/bitmap: fix wrong cleanupShaohua Li1-3/+1
if bitmap_create fails, the bitmap is already cleaned up and the returned value is an error number. We can't do the cleanup again. Reported-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Shaohua Li <shli@fb.com>
2016-08-05MD: hold mddev lock to change bitmap locationShaohua Li1-14/+33
Changing the location changes a lot of things. Holding the lock to avoid race. This makes the .quiesce called with mddev lock hold too. Acked-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-06-07md: use bio op accessorsMike Christie1-1/+1
Separate the op from the rq_flag_bits and have md set/get the bio using bio_set_op_attrs/bio_op. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07fs: have submit_bh users pass in op and flags separatelyMike Christie1-2/+2
This has submit_bh users pass in the operation and flags separately, so submit_bh_wbc can setup the bio op and bi_rw flags on the bio that is submitted. Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-09md-cluster: gather resync infos and enable recv_thread after bitmap is readyGuoqing Jiang1-0/+3
The in-memory bitmap is not ready when node joins cluster, so it doesn't make sense to make gather_all_resync_info() called so earlier, we need to call it after the node's bitmap is setup. Also, recv_thread could be wake up after node joins cluster, but it could cause problem if node receives RESYNCING message without persionality since mddev->pers->quiesce is called in process_suspend_info. This commit introduces a new cluster interface load_bitmaps to fix above problems, load_bitmaps is called in bitmap_load where bitmap and persionality are ready, and load_bitmaps does the following tasks: 1. call gather_all_resync_info to load all the node's bitmap info. 2. set MD_CLUSTER_ALREADY_IN_CLUSTER bit to recv_thread could be wake up, and wake up recv_thread if there is pending recv event. Then ack_bast only wakes up recv_thread after IN_CLUSTER bit is ready otherwise MD_CLUSTER_PENDING_RESYNC_EVENT is set. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-04md-cluster: fix ifnullfree.cocci warningskbuild test robot1-2/+1
drivers/md/bitmap.c:2049:6-11: WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values. NULL check before some freeing functions is not needed. Based on checkpatch warning "kfree(NULL) is safe this check is probably not required" and kfreeaddr.cocci by Julia Lawall. Generated by: scripts/coccinelle/free/ifnullfree.cocci Acked-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-04md-cluster/bitmap: unplug bitmap to sync dirty pages to diskGuoqing Jiang1-5/+5
This patch is doing two distinct but related things. 1. It adds bitmap_unplug() for the main bitmap (mddev->bitmap). As bit have been set, BITMAP_PAGE_DIRTY is set so bitmap_deamon_work() will not write those pages out in its regular scans, only bitmap_unplug() will. If there are no writes to the array, bitmap_unplug() won't be called, so we need to call it explicitly here. 2. bitmap_write_all() is a bit of a confusing interface as it doesn't actually write anything. The current code for writing "bitmap" works but this change makes it a bit clearer. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-04md-cluster/bitmap: fix wrong page num in bitmap_file_clear_bit and bitmap_file_set_bitGuoqing Jiang1-3/+13
The pnum passed to set_page_attr and test_page_attr should from 0 to storage.file_pages - 1, but bitmap_file_set_bit and bitmap_file_clear_bit call set_page_attr and test_page_attr with page->index parameter while page->index has already added node_offset before. So we need to minus node_offset in both bitmap_file_clear_bit and bitmap_file_set_bit. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-04md-cluster/bitmap: fix wrong calcuation of offsetGuoqing Jiang1-1/+1
The offset is wrong in bitmap_storage_alloc, we should set it like below in bitmap_init_from_disk(). node_offset = bitmap->cluster_slot * (DIV_ROUND_UP(store->bytes, PAGE_SIZE)); Because 'offset' is only assigned to 'page->index' and that is usually over-written by read_sb_page. So it does not cause problem in general, but it still need to be fixed. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-04md-cluster: sync bitmap when node received RESYNCING msgGuoqing Jiang1-0/+21
If the node received RESYNCING message which means another node will perform resync with the area, then we don't want to do it again in another node. Let's set RESYNC_MASK and clear NEEDED_MASK for the region from old-low to new-low which has finished syncing, and the region from old-hi to new-hi is about to syncing, bitmap_sync_with_cluste is introduced for the purpose. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-05-04md-cluster: always setup in-memory bitmapGuoqing Jiang1-2/+35
The in-memory bitmap for raid is allocated on demand, then for cluster scenario, it is possible that slave node which received RESYNCING message doesn't have the in-memory bitmap when master node is perform resyncing, so we can't make bitmap is match up well among each nodes. So for cluster scenario, we need always preserve the bitmap, and ensure the page will not be freed. And a no_hijack flag is introduced to both bitmap_checkpage and bitmap_get_counter, which makes cluster raid returns fail once allocate failed. And the next patch is relied on this change since it keeps sync bitmap among each nodes during resyncing stage. Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-04-09Merge tag 'md/4.6-rc2-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/mdLinus Torvalds1-8/+11
Pull MD fixes from Shaohua Li: "This update mainly fixes bugs: - fix error handling (Guoqing) - fix a crash when a disk is hotremoved (me) - fix a dead loop (Wei Fang)" * tag 'md/4.6-rc2-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: md/bitmap: clear bitmap if bitmap_create failed MD: add rdev reference for super write md: fix a trivial typo in comments md:raid1: fix a dead loop when read from a WriteMostly disk
2016-04-04mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macrosKirill A. Shutemov1-1/+1
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01md/bitmap: clear bitmap if bitmap_create failedGuoqing Jiang1-8/+11
If bitmap_create returns an error, we need to call either bitmap_destroy or bitmap_free to do clean up, and the selection is based on mddev->bitmap is set or not. And the sysfs_put(bitmap->sysfs_can_clear) is moved from bitmap_destroy to bitmap_free, and the comment of bitmap_create is changed as well. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-03-14md/bitmap: remove redundant return in bitmap_checkpageGuoqing Jiang1-1/+0
The "return 0" is not needed since bitmap_checkpage will finally return 0 for the case. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-03-07md/bitmap: remove redundant checkEric Engestrom1-2/+1
daemon_sleep is an unsigned, so testing if it's 0 or less than 1 does the same thing. Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com> Signed-off-by: Shaohua Li <shli@fb.com>
2016-01-24md-cluster: delete useless codeShaohua Li1-4/+0
page->index already considers node offset. The node_offset calculation in write_sb_page is useless and confusion. Cc: Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: NeilBrown <neilb@suse.com> Acked-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
2015-10-12md-cluster: Use a small window for resyncGoldwyn Rodrigues1-2/+2
Suspending the entire device for resync could take too long. Resync in small chunks. cluster's resync window (32M) is maintained in r1conf as cluster_sync_low and cluster_sync_high and processed in raid1's sync_request(). If the current resync is outside the cluster resync window: 1. Set the cluster_sync_low to curr_resync_completed. 2. Check if the sync will fit in the new window, if not issue a wait_barrier() and set cluster_sync_low to sector_nr. 3. Set cluster_sync_high to cluster_sync_low + resync_window. 4. Send a message to all nodes so they may add it in their suspension list. bitmap_cond_end_sync is modified to allow to force a sync inorder to get the curr_resync_completed uptodate with the sector passed. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-10-12md: Increment version for clustered bitmapsGoldwyn Rodrigues1-6/+4
Add BITMAP_MAJOR_CLUSTERED as 5, in order to prevent older kernels to assemble a clustered device. In order to maximize compatibility, the major version is set to BITMAP_MAJOR_CLUSTERED *only* if the bitmap is clustered. Added MD_FEATURE_CLUSTERED in order to return error for older kernels which would assemble MD even if the bitmap is corrupted. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.com>
2015-10-02md/bitmap: don't pass -1 to bitmap_storage_alloc.NeilBrown1-1/+2
Passing -1 to bitmap_storage_alloc() causes page->index to be set to -1, which is quite problematic. So only pass ->cluster_slot if mddev_is_clustered(). Fixes: b97e92574c0b ("Use separate bitmaps for each nodes in the cluster") Cc: stable@vger.kernel.org (v4.1+) Signed-off-by: NeilBrown <neilb@suse.com>
2015-07-25Merge tag 'md/4.2-fixes' of git://neil.brown.name/mdLinus Torvalds1-11/+17
Pull md fixes from Neil Brown: "Some md fixes for 4.2 Several are tagged for -stable. A few aren't because they are not very, serious or because they are in the 'experimental' cluster code" * tag 'md/4.2-fixes' of git://neil.brown.name/md: md/raid5: clear R5_NeedReplace when no longer needed. Fix read-balancing during node failure md-cluster: fix bitmap sub-offset in bitmap_read_sb md: Return error if request_module fails and returns positive value md: Skip cluster setup in case of error while reading bitmap md/raid1: fix test for 'was read error from last working device'. md: Skip cluster setup for dm-raid md: flush ->event_work before stopping array. md/raid10: always set reshape_safe when initializing reshape_position. md/raid5: avoid races when changing cache size.
2015-07-24md-cluster: fix bitmap sub-offset in bitmap_read_sbGoldwyn Rodrigues1-7/+4
bitmap_read_sb is modifying mddev->bitmap_info.offset. This works for the first bitmap read. However, when multiple bitmaps need to be opened by the same node, it ends up corrupting the offset. Fix it by using a local variable. Also, bitmap_read_sb is not required in bitmap_copy_from_slot since it is called in bitmap_create. Remove bitmap_read_sb(). Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.com>
2015-07-24md: Skip cluster setup in case of error while reading bitmapGoldwyn Rodrigues1-1/+1
If the bitmap read fails, the error code set is -EINVAL. However, we don't check for errors and go ahead with cluster_setup. Skip the cluster setup in case of error. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.com>
2015-07-23md: Skip cluster setup for dm-raidGoldwyn Rodrigues1-3/+12
There is a bug that the bitmap superblock isn't initialised properly for dm-raid, so a new field can have garbage in new fields. (dm-raid does initialisation in the kernel - md initialised the superblock in mdadm). This means that for dm-raid we cannot currently trust the new ->nodes field. So: - use __GFP_ZERO to initialise the superblock properly for all new arrays - initialise all fields in bitmap_info in bitmap_new_disk_sb - ignore ->nodes for dm arrays (yes, this is a hack) This bug exposes dm-raid to bug in the (still experimental) md-cluster code, so it is suitable for -stable. It does cause crashes. References: https://bugzilla.kernel.org/show_bug.cgi?id=100491 Cc: stable@vger.kernel.org (v4.1) Signed-off-By: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.com>
2015-07-04Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds1-2/+2
Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...
2015-06-23vfs: add seq_file_path() helperMiklos Szeredi1-1/+1
Turn seq_path(..., &file->f_path, ...); into seq_file_path(..., file, ...); Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23vfs: add file_path() helperMiklos Szeredi1-1/+1
Turn d_path(&file->f_path, ...); into file_path(file, ...); Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-21md/bitmap: remove rcu annotation from pointer arithmetic.NeilBrown1-1/+6
Evaluating "&mddev->disks" is simple pointer arithmetic, so it does not need 'rcu' annotations - no dereferencing is happening. Also enhance the comment to explain that 'rdev' in that case is not actually a pointer to an rdev. Reported-by: Patrick Marlier <patrick.marlier@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-22md-cluster: re-add capabilitiesGoldwyn Rodrigues1-9/+11
When "re-add" is writted to /sys/block/mdXX/md/dev-YYY/state, the clustered md: 1. Sends RE_ADD message with the desc_nr. Nodes receiving the message clear the Faulty bit in their respective rdev->flags. 2. The node initiating re-add, gathers the bitmaps of all nodes and copies them into the local bitmap. It does not clear the bitmap from which it is copying. 3. Initiating node schedules a md recovery to sync the devices. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-03-25md: Fix bitmap offset calculationsGoldwyn Rodrigues1-4/+3
The calculations of bitmap offset is incorrect with respect to bits to bytes conversion. Also, remove an irrelevant duplicate message. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-03-04md/bitmap: use sector_div for sector_t divisionsStephen Rothwell1-2/+3
neilb: modified to not corrupt ->resync_max_sectors. sector_div usage fixed by Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: NeilBrown <neilb@suse.de>
2015-03-04md/bitmap: fix incorrect DIV_ROUND_UP usage.NeilBrown1-2/+2
DIV_ROUTND_UP doesn't work on "long long", - and it should be sector_t anyway. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-23Copy set bits from another slotGoldwyn Rodrigues1-1/+77
bitmap_copy_from_slot reads the bitmap from the slot mentioned. It then copies the set bits to the node local bitmap. This is helper function for the resync operation on node failure. bitmap_set_memory_bits() currently assumes it is only run at startup and that they bitmap is currently empty. So if it finds that a region is already marked as dirty, it won't mark it dirty again. Change bitmap_set_memory_bits() to always set the NEEDED_MASK bit if 'needed' is set. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23bitmap_create returns bitmap pointerGoldwyn Rodrigues1-24/+36
This is done to have multiple bitmaps open at the same time. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Use separate bitmaps for each nodes in the clusterGoldwyn Rodrigues1-10/+57
On-disk format: 0 4k 8k 12k ------------------------------------------------------------------- | idle | md super | bm super [0] + bits | | bm bits[0, contd] | bm super[1] + bits | bm bits[1, contd] | | bm super[2] + bits | bm bits [2, contd] | bm super[3] + bits | | bm bits [3, contd] | | | Bitmap super has a field nodes, which defines the maximum number of nodes the device can use. While reading the bitmap super, if the cluster finds out that the number of nodes is > 0: 1. Requests the md-cluster module. 2. Calls md_cluster_ops->join(), which sets up clustering such as joining DLM lockspace. Since the first time, the first bitmap is read. After the call to the cluster_setup, the bitmap offset is adjusted and the superblock is re-read. This also ensures the bitmap is read the bitmap lock (when bitmap lock is introduced in later patches) Questions: 1. cluster name is repeated in all bitmap supers. Is that okay? Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Add node recovery callbacksGoldwyn Rodrigues1-0/+1
DLM offers callbacks when a node fails and the lock remastery is performed: 1. recover_prep: called when DLM discovers a node is down 2. recover_slot: called when DLM identifies the node and recovery can start 3. recover_done: called when all nodes have completed recover_slot recover_slot() and recover_done() are also called when the node joins initially in order to inform the node with its slot number. These slot numbers start from one, so we deduct one to make it start with zero which the cluster-md code uses. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Introduce md_cluster_infoGoldwyn Rodrigues1-1/+8
md_cluster_info stores the cluster information in the MD device. The join() is called when mddev detects it is a clustered device. The main responsibilities are: 1. Setup a DLM lockspace 2. Setup all initial locks such as super block locks and bitmap lock (will come later) The leave() clears up the lockspace and all the locks held. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-06md: remove mddev_lock() from md_attr_show()NeilBrown1-3/+10
Most attributes can be read safely without any locking. A race might lead to a slightly out-dated value, but nothing wrong. We already have locking in some places where needed. All that remains is can_clear_show(), behind_writes_used_show() and action_show() which are easily fixed. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-06md/bitmap: protect clearing of ->bitmap by mddev->lockNeilBrown1-0/+2
This makes it safe to inspect the struct while holding only the spinlock. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-02md/bitmap: fix a might_sleep() warning.NeilBrown1-0/+13
commit 8eb23b9f35aae413140d3fda766a98092c21e9b0 sched: Debug nested sleeps causes false-positive warnings in RAID5 code. This annotation removes them and adds a comment explaining why there is no real problem. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-09md/bitmap: always wait for writes on unplug.NeilBrown1-10/+6
If two threads call bitmap_unplug at the same time, then one might schedule all the writes, and the other might decide that it doesn't need to wait. But really it does. It rarely hurts to wait when it isn't absolutely necessary, and the current code doesn't really focus on 'absolutely necessary' anyway. So just wait always. This can potentially lead to data corruption if a crash happens at an awkward time and data was written before the bitmap was updated. It is very unlikely, but this should go to -stable just to be safe. Appropriate for any -stable. Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@vger.kernel.org (please delay until 3.18 is released)
2014-05-29md/bitmap: remove confusing code from filemap_get_page.NeilBrown1-5/+1
file_page_index(store, 0) is *always* 0. This is because the bitmap sb, at 256 bytes, is *always* less than one page. So subtracting it has no effect and the code should be removed. Reported-by: Goldwyn Rodrigues <rgoldwyn@suse.de> Signed-off-by: NeilBrown <neilb@suse.de>
2014-04-09md/bitmap: don't abuse i_writecount for bitmap files.NeilBrown1-1/+0
md bitmap code currently tries to use i_writecount to stop any other process from writing to out bitmap file. But that is really an abuse and has bit-rotted so locking is all wrong. So discard that - root should be allowed to shoot self in foot. Still use it in a much less intrusive way to stop the same file being used as bitmap on two different array, and apply other checks to ensure the file is at least vaguely usable for bitmap storage (is regular, is open for write. Support for ->bmap is already checked elsewhere). Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: NeilBrown <neilb@suse.de>
2013-12-11kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordinglyTejun Heo1-1/+1
kernfs has just been separated out from sysfs and we're already in full conflict mode. Nothing can make the situation any worse. Let's take the chance to name things properly. This patch performs the following renames. * s/sysfs_elem_dir/kernfs_elem_dir/ * s/sysfs_elem_symlink/kernfs_elem_symlink/ * s/sysfs_elem_attr/kernfs_elem_file/ * s/sysfs_dirent/kernfs_node/ * s/sd/kn/ in kernfs proper * s/parent_sd/parent/ * s/target_sd/target/ * s/dir_sd/parent/ * s/to_sysfs_dirent()/rb_to_kn()/ * misc renames of local vars when they conflict with the above Because md, mic and gpio dig into sysfs details, this patch ends up modifying them. All are sysfs_dirent renames and trivial. While we can avoid these by introducing a dummy wrapping struct sysfs_dirent around kernfs_node, given the limited usage outside kernfs and sysfs proper, I don't think such workaround is called for. This patch is strictly rename only and doesn't introduce any functional difference. - mic / gpio renames were missing. Spotted by kbuild test robot. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Neil Brown <neilb@suse.de> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Ashutosh Dixit <ashutosh.dixit@intel.com> Cc: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>