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author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-12-15 23:53:37 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-12-15 23:53:37 +0300 |
commit | ee1b43ece1533ee60b876fd75ddb20ba1ea186bb (patch) | |
tree | d049463295c3aa2fdb21d08509821452b67d2d4f /drivers/md | |
parent | 66dbbd72005c5ebdd1de35ba5a41393f01df48d6 (diff) | |
parent | fbc7c07ec23c040179384a1f16b62b6030eb6bdd (diff) | |
download | linux-ee1b43ece1533ee60b876fd75ddb20ba1ea186bb.tar.xz |
Merge tag 'for-4.15/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- fix a particularly nasty DM core bug in a 4.15 refcount_t conversion.
- fix various targets to dm_register_target after module __init
resources created; otherwise racing lvm2 commands could result in a
NULL pointer during initialization of associated DM kernel module.
- fix regression in bio-based DM multipath queue_if_no_path handling.
- fix DM bufio's shrinker to reclaim more than one buffer per scan.
* tag 'for-4.15/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm bufio: fix shrinker scans when (nr_to_scan < retain_target)
dm mpath: fix bio-based multipath queue_if_no_path handling
dm: fix various targets to dm_register_target after module __init resources created
dm table: fix regression from improper dm_dev_internal.count refcount_t conversion
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/dm-bufio.c | 8 | ||||
-rw-r--r-- | drivers/md/dm-cache-target.c | 12 | ||||
-rw-r--r-- | drivers/md/dm-mpath.c | 67 | ||||
-rw-r--r-- | drivers/md/dm-snap.c | 48 | ||||
-rw-r--r-- | drivers/md/dm-table.c | 5 | ||||
-rw-r--r-- | drivers/md/dm-thin.c | 22 |
6 files changed, 100 insertions, 62 deletions
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index b8ac591aaaa7..c546b567f3b5 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -1611,7 +1611,8 @@ static unsigned long __scan(struct dm_bufio_client *c, unsigned long nr_to_scan, int l; struct dm_buffer *b, *tmp; unsigned long freed = 0; - unsigned long count = nr_to_scan; + unsigned long count = c->n_buffers[LIST_CLEAN] + + c->n_buffers[LIST_DIRTY]; unsigned long retain_target = get_retain_buffers(c); for (l = 0; l < LIST_SIZE; l++) { @@ -1647,8 +1648,11 @@ static unsigned long dm_bufio_shrink_count(struct shrinker *shrink, struct shrink_control *sc) { struct dm_bufio_client *c = container_of(shrink, struct dm_bufio_client, shrinker); + unsigned long count = READ_ONCE(c->n_buffers[LIST_CLEAN]) + + READ_ONCE(c->n_buffers[LIST_DIRTY]); + unsigned long retain_target = get_retain_buffers(c); - return READ_ONCE(c->n_buffers[LIST_CLEAN]) + READ_ONCE(c->n_buffers[LIST_DIRTY]); + return (count < retain_target) ? 0 : (count - retain_target); } /* diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index cf23a14f9c6a..47407e43b96a 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -3472,18 +3472,18 @@ static int __init dm_cache_init(void) { int r; - r = dm_register_target(&cache_target); - if (r) { - DMERR("cache target registration failed: %d", r); - return r; - } - migration_cache = KMEM_CACHE(dm_cache_migration, 0); if (!migration_cache) { dm_unregister_target(&cache_target); return -ENOMEM; } + r = dm_register_target(&cache_target); + if (r) { + DMERR("cache target registration failed: %d", r); + return r; + } + return 0; } diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index c8faa2b85842..f7810cc869ac 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -458,6 +458,38 @@ do { \ } while (0) /* + * Check whether bios must be queued in the device-mapper core rather + * than here in the target. + * + * If MPATHF_QUEUE_IF_NO_PATH and MPATHF_SAVED_QUEUE_IF_NO_PATH hold + * the same value then we are not between multipath_presuspend() + * and multipath_resume() calls and we have no need to check + * for the DMF_NOFLUSH_SUSPENDING flag. + */ +static bool __must_push_back(struct multipath *m, unsigned long flags) +{ + return ((test_bit(MPATHF_QUEUE_IF_NO_PATH, &flags) != + test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &flags)) && + dm_noflush_suspending(m->ti)); +} + +/* + * Following functions use READ_ONCE to get atomic access to + * all m->flags to avoid taking spinlock + */ +static bool must_push_back_rq(struct multipath *m) +{ + unsigned long flags = READ_ONCE(m->flags); + return test_bit(MPATHF_QUEUE_IF_NO_PATH, &flags) || __must_push_back(m, flags); +} + +static bool must_push_back_bio(struct multipath *m) +{ + unsigned long flags = READ_ONCE(m->flags); + return __must_push_back(m, flags); +} + +/* * Map cloned requests (request-based multipath) */ static int multipath_clone_and_map(struct dm_target *ti, struct request *rq, @@ -478,7 +510,7 @@ static int multipath_clone_and_map(struct dm_target *ti, struct request *rq, pgpath = choose_pgpath(m, nr_bytes); if (!pgpath) { - if (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) + if (must_push_back_rq(m)) return DM_MAPIO_DELAY_REQUEUE; dm_report_EIO(m); /* Failed */ return DM_MAPIO_KILL; @@ -553,7 +585,7 @@ static int __multipath_map_bio(struct multipath *m, struct bio *bio, struct dm_m } if (!pgpath) { - if (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) + if (must_push_back_bio(m)) return DM_MAPIO_REQUEUE; dm_report_EIO(m); return DM_MAPIO_KILL; @@ -651,8 +683,7 @@ static int queue_if_no_path(struct multipath *m, bool queue_if_no_path, assign_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags, (save_old_value && test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) || (!save_old_value && queue_if_no_path)); - assign_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags, - queue_if_no_path || dm_noflush_suspending(m->ti)); + assign_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags, queue_if_no_path); spin_unlock_irqrestore(&m->lock, flags); if (!queue_if_no_path) { @@ -1486,7 +1517,7 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone, fail_path(pgpath); if (atomic_read(&m->nr_valid_paths) == 0 && - !test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) { + !must_push_back_rq(m)) { if (error == BLK_STS_IOERR) dm_report_EIO(m); /* complete with the original error */ @@ -1521,8 +1552,12 @@ static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, if (atomic_read(&m->nr_valid_paths) == 0 && !test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) { - dm_report_EIO(m); - *error = BLK_STS_IOERR; + if (must_push_back_bio(m)) { + r = DM_ENDIO_REQUEUE; + } else { + dm_report_EIO(m); + *error = BLK_STS_IOERR; + } goto done; } @@ -1957,13 +1992,6 @@ static int __init dm_multipath_init(void) { int r; - r = dm_register_target(&multipath_target); - if (r < 0) { - DMERR("request-based register failed %d", r); - r = -EINVAL; - goto bad_register_target; - } - kmultipathd = alloc_workqueue("kmpathd", WQ_MEM_RECLAIM, 0); if (!kmultipathd) { DMERR("failed to create workqueue kmpathd"); @@ -1985,13 +2013,20 @@ static int __init dm_multipath_init(void) goto bad_alloc_kmpath_handlerd; } + r = dm_register_target(&multipath_target); + if (r < 0) { + DMERR("request-based register failed %d", r); + r = -EINVAL; + goto bad_register_target; + } + return 0; +bad_register_target: + destroy_workqueue(kmpath_handlerd); bad_alloc_kmpath_handlerd: destroy_workqueue(kmultipathd); bad_alloc_kmultipathd: - dm_unregister_target(&multipath_target); -bad_register_target: return r; } diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 1113b42e1eda..a0613bd8ed00 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -2411,24 +2411,6 @@ static int __init dm_snapshot_init(void) return r; } - r = dm_register_target(&snapshot_target); - if (r < 0) { - DMERR("snapshot target register failed %d", r); - goto bad_register_snapshot_target; - } - - r = dm_register_target(&origin_target); - if (r < 0) { - DMERR("Origin target register failed %d", r); - goto bad_register_origin_target; - } - - r = dm_register_target(&merge_target); - if (r < 0) { - DMERR("Merge target register failed %d", r); - goto bad_register_merge_target; - } - r = init_origin_hash(); if (r) { DMERR("init_origin_hash failed."); @@ -2449,19 +2431,37 @@ static int __init dm_snapshot_init(void) goto bad_pending_cache; } + r = dm_register_target(&snapshot_target); + if (r < 0) { + DMERR("snapshot target register failed %d", r); + goto bad_register_snapshot_target; + } + + r = dm_register_target(&origin_target); + if (r < 0) { + DMERR("Origin target register failed %d", r); + goto bad_register_origin_target; + } + + r = dm_register_target(&merge_target); + if (r < 0) { + DMERR("Merge target register failed %d", r); + goto bad_register_merge_target; + } + return 0; -bad_pending_cache: - kmem_cache_destroy(exception_cache); -bad_exception_cache: - exit_origin_hash(); -bad_origin_hash: - dm_unregister_target(&merge_target); bad_register_merge_target: dm_unregister_target(&origin_target); bad_register_origin_target: dm_unregister_target(&snapshot_target); bad_register_snapshot_target: + kmem_cache_destroy(pending_cache); +bad_pending_cache: + kmem_cache_destroy(exception_cache); +bad_exception_cache: + exit_origin_hash(); +bad_origin_hash: dm_exception_store_exit(); return r; diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 88130b5d95f9..aaffd0c0ee9a 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -453,14 +453,15 @@ int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, refcount_set(&dd->count, 1); list_add(&dd->list, &t->devices); + goto out; } else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) { r = upgrade_mode(dd, mode, t->md); if (r) return r; - refcount_inc(&dd->count); } - + refcount_inc(&dd->count); +out: *result = dd->dm_dev; return 0; } diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 89e5dff9b4cf..f91d771fff4b 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -4355,30 +4355,28 @@ static struct target_type thin_target = { static int __init dm_thin_init(void) { - int r; + int r = -ENOMEM; pool_table_init(); + _new_mapping_cache = KMEM_CACHE(dm_thin_new_mapping, 0); + if (!_new_mapping_cache) + return r; + r = dm_register_target(&thin_target); if (r) - return r; + goto bad_new_mapping_cache; r = dm_register_target(&pool_target); if (r) - goto bad_pool_target; - - r = -ENOMEM; - - _new_mapping_cache = KMEM_CACHE(dm_thin_new_mapping, 0); - if (!_new_mapping_cache) - goto bad_new_mapping_cache; + goto bad_thin_target; return 0; -bad_new_mapping_cache: - dm_unregister_target(&pool_target); -bad_pool_target: +bad_thin_target: dm_unregister_target(&thin_target); +bad_new_mapping_cache: + kmem_cache_destroy(_new_mapping_cache); return r; } |