path: root/drivers
diff options
authorTang Junhui <tang.junhui@zte.com.cn>2018-02-07 11:41:46 -0800
committerJens Axboe <axboe@kernel.dk>2018-02-07 12:50:01 -0700
commit73ac105be390c1de42a2f21643c9778a5e002930 (patch)
tree9a9920614c0e4092f4479413d631912c58e5c952 /drivers
parent7f4fc93d4713394ee8f1cd44c238e046e11b4f15 (diff)
bcache: fix for data collapse after re-attaching an attached device
back-end device sdm has already attached a cache_set with ID f67ebe1f-f8bc-4d73-bfe5-9dc88607f119, then try to attach with another cache set, and it returns with an error: [root]# cd /sys/block/sdm/bcache [root]# echo 5ccd0a63-148e-48b8-afa2-aca9cbd6279f > attach -bash: echo: write error: Invalid argument After that, execute a command to modify the label of bcache device: [root]# echo data_disk1 > label Then we reboot the system, when the system power on, the back-end device can not attach to cache_set, a messages show in the log: Feb 5 12:05:52 ceph152 kernel: [922385.508498] bcache: bch_cached_dev_attach() couldn't find uuid for sdm in set In sysfs_attach(), dc->sb.set_uuid was assigned to the value which input through sysfs, no matter whether it is success or not in bch_cached_dev_attach(). For example, If the back-end device has already attached to an cache set, bch_cached_dev_attach() would fail, but dc->sb.set_uuid was changed. Then modify the label of bcache device, it will call bch_write_bdev_super(), which would write the dc->sb.set_uuid to the super block, so we record a wrong cache set ID in the super block, after the system reboot, the cache set couldn't find the uuid of the back-end device, so the bcache device couldn't exist and use any more. In this patch, we don't assigned cache set ID to dc->sb.set_uuid in sysfs_attach() directly, but input it into bch_cached_dev_attach(), and assigned dc->sb.set_uuid to the cache set ID after the back-end device attached to the cache set successful. Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn> Reviewed-by: Michael Lyle <mlyle@lyle.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers')
3 files changed, 11 insertions, 7 deletions
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index b8c2e1bef1f1..12e5197f186c 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -924,7 +924,7 @@ void bcache_write_super(struct cache_set *);
int bch_flash_dev_create(struct cache_set *c, uint64_t size);
-int bch_cached_dev_attach(struct cached_dev *, struct cache_set *);
+int bch_cached_dev_attach(struct cached_dev *, struct cache_set *, uint8_t *);
void bch_cached_dev_detach(struct cached_dev *);
void bch_cached_dev_run(struct cached_dev *);
void bcache_device_stop(struct bcache_device *);
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index a2ad37a8afc0..312895788036 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -957,7 +957,8 @@ void bch_cached_dev_detach(struct cached_dev *dc)
-int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c)
+int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
+ uint8_t *set_uuid)
uint32_t rtime = cpu_to_le32(get_seconds());
struct uuid_entry *u;
@@ -965,7 +966,8 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c)
bdevname(dc->bdev, buf);
- if (memcmp(dc->sb.set_uuid, c->sb.set_uuid, 16))
+ if ((set_uuid && memcmp(set_uuid, c->sb.set_uuid, 16)) ||
+ (!set_uuid && memcmp(dc->sb.set_uuid, c->sb.set_uuid, 16)))
return -ENOENT;
if (dc->disk.c) {
@@ -1194,7 +1196,7 @@ static void register_bdev(struct cache_sb *sb, struct page *sb_page,
list_add(&dc->list, &uncached_devices);
list_for_each_entry(c, &bch_cache_sets, list)
- bch_cached_dev_attach(dc, c);
+ bch_cached_dev_attach(dc, c, NULL);
if (BDEV_STATE(&dc->sb) == BDEV_STATE_NONE ||
@@ -1716,7 +1718,7 @@ static void run_cache_set(struct cache_set *c)
list_for_each_entry_safe(dc, t, &uncached_devices, list)
- bch_cached_dev_attach(dc, c);
+ bch_cached_dev_attach(dc, c, NULL);
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index a7552f509f50..78cd7bd50fdd 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -272,12 +272,14 @@ STORE(__cached_dev)
if (attr == &sysfs_attach) {
- if (bch_parse_uuid(buf, dc->sb.set_uuid) < 16)
+ uint8_t set_uuid[16];
+ if (bch_parse_uuid(buf, set_uuid) < 16)
return -EINVAL;
v = -ENOENT;
list_for_each_entry(c, &bch_cache_sets, list) {
- v = bch_cached_dev_attach(dc, c);
+ v = bch_cached_dev_attach(dc, c, set_uuid);
if (!v)
return size;

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