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author | Artur Paszkiewicz <artur.paszkiewicz@intel.com> | 2017-05-08 11:56:55 +0200 |
---|---|---|
committer | Shaohua Li <shli@fb.com> | 2017-05-08 10:32:59 -0700 |
commit | 2214c260c72b0bd94e6c1c19bf451686212025d3 (patch) | |
tree | 829a3494857d6bd61c38171a39e2e207de585e38 /drivers/md | |
parent | 3d05f3aed5d721c2c77d20288c29ab26c6193ed5 (diff) | |
download | linux-stable-2214c260c72b0bd94e6c1c19bf451686212025d3.tar.gz linux-stable-2214c260c72b0bd94e6c1c19bf451686212025d3.tar.bz2 linux-stable-2214c260c72b0bd94e6c1c19bf451686212025d3.zip |
md: don't return -EAGAIN in md_allow_write for external metadata arrays
This essentially reverts commit b5470dc5fc18 ("md: resolve external
metadata handling deadlock in md_allow_write") with some adjustments.
Since commit 6791875e2e53 ("md: make reconfig_mutex optional for writes
to md sysfs files.") changing array_state to 'active' does not use
mddev_lock() and will not cause a deadlock with md_allow_write(). This
revert simplifies userspace tools that write to sysfs attributes like
"stripe_cache_size" or "consistency_policy" because it removes the need
for special handling for external metadata arrays, checking for EAGAIN
and retrying the write.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/md.c | 20 | ||||
-rw-r--r-- | drivers/md/md.h | 2 | ||||
-rw-r--r-- | drivers/md/raid1.c | 9 | ||||
-rw-r--r-- | drivers/md/raid5.c | 12 |
4 files changed, 15 insertions, 28 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 82f798be964f..10367ffe92e3 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -8022,18 +8022,15 @@ EXPORT_SYMBOL(md_write_end); * may proceed without blocking. It is important to call this before * attempting a GFP_KERNEL allocation while holding the mddev lock. * Must be called with mddev_lock held. - * - * In the ->external case MD_SB_CHANGE_PENDING can not be cleared until mddev->lock - * is dropped, so return -EAGAIN after notifying userspace. */ -int md_allow_write(struct mddev *mddev) +void md_allow_write(struct mddev *mddev) { if (!mddev->pers) - return 0; + return; if (mddev->ro) - return 0; + return; if (!mddev->pers->sync_request) - return 0; + return; spin_lock(&mddev->lock); if (mddev->in_sync) { @@ -8046,13 +8043,12 @@ int md_allow_write(struct mddev *mddev) spin_unlock(&mddev->lock); md_update_sb(mddev, 0); sysfs_notify_dirent_safe(mddev->sysfs_state); + /* wait for the dirty state to be recorded in the metadata */ + wait_event(mddev->sb_wait, + !test_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags) && + !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)); } else spin_unlock(&mddev->lock); - - if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) - return -EAGAIN; - else - return 0; } EXPORT_SYMBOL_GPL(md_allow_write); diff --git a/drivers/md/md.h b/drivers/md/md.h index 4e75d121bfcc..11f15146ce51 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -665,7 +665,7 @@ extern int sync_page_io(struct md_rdev *rdev, sector_t sector, int size, bool metadata_op); extern void md_do_sync(struct md_thread *thread); extern void md_new_event(struct mddev *mddev); -extern int md_allow_write(struct mddev *mddev); +extern void md_allow_write(struct mddev *mddev); extern void md_wait_for_blocked_rdev(struct md_rdev *rdev, struct mddev *mddev); extern void md_set_array_sectors(struct mddev *mddev, sector_t array_sectors); extern int md_check_no_bitmap(struct mddev *mddev); diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 7ed59351fe97..7c1f73398800 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -3197,7 +3197,7 @@ static int raid1_reshape(struct mddev *mddev) struct r1conf *conf = mddev->private; int cnt, raid_disks; unsigned long flags; - int d, d2, err; + int d, d2; /* Cannot change chunk_size, layout, or level */ if (mddev->chunk_sectors != mddev->new_chunk_sectors || @@ -3209,11 +3209,8 @@ static int raid1_reshape(struct mddev *mddev) return -EINVAL; } - if (!mddev_is_clustered(mddev)) { - err = md_allow_write(mddev); - if (err) - return err; - } + if (!mddev_is_clustered(mddev)) + md_allow_write(mddev); raid_disks = mddev->raid_disks + mddev->delta_disks; diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 3809a2192132..f8055a7abb4b 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2309,14 +2309,12 @@ static int resize_stripes(struct r5conf *conf, int newsize) struct stripe_head *osh, *nsh; LIST_HEAD(newstripes); struct disk_info *ndisks; - int err; + int err = 0; struct kmem_cache *sc; int i; int hash, cnt; - err = md_allow_write(conf->mddev); - if (err) - return err; + md_allow_write(conf->mddev); /* Step 1 */ sc = kmem_cache_create(conf->cache_name[1-conf->active_name], @@ -6310,7 +6308,6 @@ int raid5_set_cache_size(struct mddev *mddev, int size) { struct r5conf *conf = mddev->private; - int err; if (size <= 16 || size > 32768) return -EINVAL; @@ -6322,10 +6319,7 @@ raid5_set_cache_size(struct mddev *mddev, int size) ; mutex_unlock(&conf->cache_size_mutex); - - err = md_allow_write(mddev); - if (err) - return err; + md_allow_write(mddev); mutex_lock(&conf->cache_size_mutex); while (size > conf->max_nr_stripes) |