From cb3e217bdb39e390f8e64af519acb02af336b53d Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Sun, 13 Nov 2022 09:32:07 +0800 Subject: btrfs: use btrfs_dev_name() helper to handle missing devices better [BUG] If dev-replace failed to re-construct its data/metadata, the kernel message would be incorrect for the missing device: BTRFS info (device dm-1): dev_replace from (devid 2) to /dev/mapper/test-scratch2 started BTRFS error (device dm-1): failed to rebuild valid logical 38862848 for dev (efault) Note the above "dev (efault)" of the second line. While the first line is properly reporting "". [CAUSE] Although dev-replace is using btrfs_dev_name(), the heavy lifting work is still done by scrub (scrub is reused by both dev-replace and regular scrub). Unfortunately scrub code never uses btrfs_dev_name() helper, as it's only declared locally inside dev-replace.c. [FIX] Fix the output by: - Move the btrfs_dev_name() helper to volumes.h - Use btrfs_dev_name() to replace open-coded rcu_str_deref() calls Only zoned code is not touched, as I'm not familiar with degraded zoned code. - Constify return value and parameter Now the output looks pretty sane: BTRFS info (device dm-1): dev_replace from (devid 2) to /dev/mapper/test-scratch2 started BTRFS error (device dm-1): failed to rebuild valid logical 38862848 for dev Reviewed-by: Anand Jain Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/dev-replace.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) (limited to 'fs/btrfs/dev-replace.c') diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c index 9c4a8649a0f4..78696d331639 100644 --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -18,7 +18,6 @@ #include "volumes.h" #include "async-thread.h" #include "check-integrity.h" -#include "rcu-string.h" #include "dev-replace.h" #include "sysfs.h" #include "zoned.h" @@ -451,14 +450,6 @@ out: return ret; } -static char* btrfs_dev_name(struct btrfs_device *device) -{ - if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) - return ""; - else - return rcu_str_deref(device->name); -} - static int mark_block_group_to_copy(struct btrfs_fs_info *fs_info, struct btrfs_device *src_dev) { @@ -674,7 +665,7 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, "dev_replace from %s (devid %llu) to %s started", btrfs_dev_name(src_device), src_device->devid, - rcu_str_deref(tgt_device->name)); + btrfs_dev_name(tgt_device)); /* * from now on, the writes to the srcdev are all duplicated to @@ -933,7 +924,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, "btrfs_scrub_dev(%s, %llu, %s) failed %d", btrfs_dev_name(src_device), src_device->devid, - rcu_str_deref(tgt_device->name), scrub_ret); + btrfs_dev_name(tgt_device), scrub_ret); error: up_write(&dev_replace->rwsem); mutex_unlock(&fs_info->chunk_mutex); @@ -951,7 +942,7 @@ error: "dev_replace from %s (devid %llu) to %s finished", btrfs_dev_name(src_device), src_device->devid, - rcu_str_deref(tgt_device->name)); + btrfs_dev_name(tgt_device)); clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &tgt_device->dev_state); tgt_device->devid = src_device->devid; src_device->devid = BTRFS_DEV_REPLACE_DEVID; -- cgit v1.2.3-73-gaa49b