* [PATCH 1/4] btrfs: set fs_root = NULL on error
2020-02-13 15:47 [PATCH 0/4][v2] Error condition failure fixes Josef Bacik
@ 2020-02-13 15:47 ` Josef Bacik
2020-02-13 15:47 ` [PATCH 2/4] btrfs: do not check delayed items are empty for single trans cleanup Josef Bacik
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Josef Bacik @ 2020-02-13 15:47 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Nikolay Borisov, Johannes Thumshirn, Qu Wenruo
While running my error injection script I hit a panic when we tried to
clean up the fs_root when free'ing the fs_root. This is because
fs_info->fs_root == PTR_ERR(-EIO), which isn't great. Fix this by
setting fs_info->fs_root = NULL; if we fail to read the root.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/disk-io.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index eb441fa3711b..5b6140482cef 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3260,6 +3260,7 @@ int __cold open_ctree(struct super_block *sb,
if (IS_ERR(fs_info->fs_root)) {
err = PTR_ERR(fs_info->fs_root);
btrfs_warn(fs_info, "failed to read fs tree: %d", err);
+ fs_info->fs_root = NULL;
goto fail_qgroup;
}
--
2.24.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 2/4] btrfs: do not check delayed items are empty for single trans cleanup
2020-02-13 15:47 [PATCH 0/4][v2] Error condition failure fixes Josef Bacik
2020-02-13 15:47 ` [PATCH 1/4] btrfs: set fs_root = NULL on error Josef Bacik
@ 2020-02-13 15:47 ` Josef Bacik
2020-02-13 15:47 ` [PATCH 3/4] btrfs: handle logged extent failure properly Josef Bacik
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Josef Bacik @ 2020-02-13 15:47 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Johannes Thumshirn, Nikolay Borisov, Qu Wenruo
btrfs_assert_delayed_root_empty() will check if the delayed root is
completely empty, but this is a fs wide check. On cleanup we may have
allowed other transactions to begin, for whatever reason, and thus the
delayed root is not empty. So remove this check from
cleanup_one_transation(). This however can stay in
btrfs_cleanup_transaction(), because it checks only after all of the
transactions have been properly cleaned up, and thus is valid.
eviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/disk-io.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 5b6140482cef..601ed3335cf6 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -4543,7 +4543,6 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
wake_up(&fs_info->transaction_wait);
btrfs_destroy_delayed_inodes(fs_info);
- btrfs_assert_delayed_root_empty(fs_info);
btrfs_destroy_marked_extents(fs_info, &cur_trans->dirty_pages,
EXTENT_DIRTY);
--
2.24.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 3/4] btrfs: handle logged extent failure properly
2020-02-13 15:47 [PATCH 0/4][v2] Error condition failure fixes Josef Bacik
2020-02-13 15:47 ` [PATCH 1/4] btrfs: set fs_root = NULL on error Josef Bacik
2020-02-13 15:47 ` [PATCH 2/4] btrfs: do not check delayed items are empty for single trans cleanup Josef Bacik
@ 2020-02-13 15:47 ` Josef Bacik
2020-02-13 15:47 ` [PATCH 4/4] btrfs: fix bytes_may_use underflow in prealloc error condtition Josef Bacik
2020-02-18 15:00 ` [PATCH 0/4][v2] Error condition failure fixes David Sterba
4 siblings, 0 replies; 6+ messages in thread
From: Josef Bacik @ 2020-02-13 15:47 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Johannes Thumshirn, Nikolay Borisov, Qu Wenruo
If we're allocating a logged extent we attempt to insert an extent
record for the file extent directly. We increase
space_info->bytes_reserved, because the extent entry addition will call
btrfs_update_block_group(), which will convert the ->bytes_reserved to
->bytes_used. However if we fail at any point while inserting the
extent entry we will bail and leave space on ->bytes_reserved, which
will trigger a WARN_ON() on umount. Fix this by pinning the space if we
fail to insert, which is what happens in every other failure case that
involves adding the extent entry.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/extent-tree.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c43acb329fa6..2b4c3ca5e651 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4430,6 +4430,8 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
ret = alloc_reserved_file_extent(trans, 0, root_objectid, 0, owner,
offset, ins, 1);
+ if (ret)
+ btrfs_pin_extent(fs_info, ins->objectid, ins->offset, 1);
btrfs_put_block_group(block_group);
return ret;
}
--
2.24.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 4/4] btrfs: fix bytes_may_use underflow in prealloc error condtition
2020-02-13 15:47 [PATCH 0/4][v2] Error condition failure fixes Josef Bacik
` (2 preceding siblings ...)
2020-02-13 15:47 ` [PATCH 3/4] btrfs: handle logged extent failure properly Josef Bacik
@ 2020-02-13 15:47 ` Josef Bacik
2020-02-18 15:00 ` [PATCH 0/4][v2] Error condition failure fixes David Sterba
4 siblings, 0 replies; 6+ messages in thread
From: Josef Bacik @ 2020-02-13 15:47 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Qu Wenruo
I hit the following warning while running my error injection stress testing
------------[ cut here ]------------
WARNING: CPU: 3 PID: 1453 at fs/btrfs/space-info.h:108 btrfs_free_reserved_data_space_noquota+0xfd/0x160 [btrfs]
RIP: 0010:btrfs_free_reserved_data_space_noquota+0xfd/0x160 [btrfs]
Call Trace:
btrfs_free_reserved_data_space+0x4f/0x70 [btrfs]
__btrfs_prealloc_file_range+0x378/0x470 [btrfs]
elfcorehdr_read+0x40/0x40
? elfcorehdr_read+0x40/0x40
? btrfs_commit_transaction+0xca/0xa50 [btrfs]
? dput+0xb4/0x2a0
? btrfs_log_dentry_safe+0x55/0x70 [btrfs]
? btrfs_sync_file+0x30e/0x420 [btrfs]
? do_fsync+0x38/0x70
? __x64_sys_fdatasync+0x13/0x20
? do_syscall_64+0x5b/0x1b0
? entry_SYSCALL_64_after_hwframe+0x44/0xa9
---[ end trace 70ccb5d0fe51151c ]---
This happens if we fail to insert our reserved file extent. At this
point we've already converted our reservation from ->bytes_may_use to
->bytes_reserved. However once we break we will attempt to free
everything from [cur_offset, end] from ->bytes_may_use, but our extent
reservation will overlap part of this.
Fix this problem by adding ins.offset (our extent allocation size) to
cur_offset so we remove the actual remaining part from ->bytes_may_use.
I validated this fix using my inject-error.py script
python inject-error.py -o should_fail_bio -t cache_save_setup -t \
__btrfs_prealloc_file_range \
-t insert_reserved_file_extent.constprop.0 \
-r "-5" ./run-fsstress.sh
where run-fsstress.sh simply mounts and runs fsstress on a disk.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/inode.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 84e649724549..ffc6fcfe805c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -9876,6 +9876,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_key ins;
u64 cur_offset = start;
+ u64 clear_offset = start;
u64 i_size;
u64 cur_bytes;
u64 last_alloc = (u64)-1;
@@ -9910,6 +9911,15 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
btrfs_end_transaction(trans);
break;
}
+
+ /*
+ * We've reserved this space, and thus converted it from
+ * ->bytes_may_use to ->bytes_reserved. Any error that happens
+ * from here on out we will only need to clear our reservation
+ * for the remaining unreserved area, so advance our
+ * clear_offset by our extent size.
+ */
+ clear_offset += ins.offset;
btrfs_dec_block_group_reservations(fs_info, ins.objectid);
last_alloc = ins.offset;
@@ -9989,9 +9999,9 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
if (own_trans)
btrfs_end_transaction(trans);
}
- if (cur_offset < end)
- btrfs_free_reserved_data_space(inode, NULL, cur_offset,
- end - cur_offset + 1);
+ if (clear_offset < end)
+ btrfs_free_reserved_data_space(inode, NULL, clear_offset,
+ end - clear_offset + 1);
return ret;
}
--
2.24.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH 0/4][v2] Error condition failure fixes
2020-02-13 15:47 [PATCH 0/4][v2] Error condition failure fixes Josef Bacik
` (3 preceding siblings ...)
2020-02-13 15:47 ` [PATCH 4/4] btrfs: fix bytes_may_use underflow in prealloc error condtition Josef Bacik
@ 2020-02-18 15:00 ` David Sterba
4 siblings, 0 replies; 6+ messages in thread
From: David Sterba @ 2020-02-18 15:00 UTC (permalink / raw)
To: Josef Bacik; +Cc: linux-btrfs, kernel-team
On Thu, Feb 13, 2020 at 10:47:27AM -0500, Josef Bacik wrote:
> v1->v2:
> - Fixed the ins.objectid thing Nikolay pointed out, and reworked that patch a
> bit to do the right thing in case of a add_extent_mapping() further down in
> that function as well.
>
> ------------------- Original email -----------------------------
> I've been running my bpf error injection stress script and been fixing what has
> fallen out. I don't think I've fixed everything yet, but to reduce the noise
> from Dave's testing here's the current set of fixes I have. These are based on
> misc-next from late last week, but should apply cleanly to the recent set.
> These aren't super important, but will cut down on the noise from things like
> generic/019 and generic/475. Thanks,
The VM with 1G of memory does not complain anymore and completes the
whole fstests. Patchset moved from topic branch to misc-next and despite
the fixes are not considered serious I'll forward them to current rc.
Thanks.
^ permalink raw reply [flat|nested] 6+ messages in thread