From: Yu Kuai <yukuai3(a)huawei.com>
stable inclusion
from stable-v5.10.224
commit c384dd4f1fb3b14a2fd199360701cc163ea88705
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAMNBN
CVE: CVE-2024-43914
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id…
--------------------------------
[ Upstream commit 305a5170dc5cf3d395bb4c4e9239bca6d0b54b49 ]
Currently, mdadm support --revert-reshape to abort the reshape while
reassembling, as the test 07revert-grow. However, following BUG_ON()
can be triggerred by the test:
kernel BUG at drivers/md/raid5.c:6278!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
irq event stamp: 158985
CPU: 6 PID: 891 Comm: md0_reshape Not tainted 6.9.0-03335-g7592a0b0049a #94
RIP: 0010:reshape_request+0x3f1/0xe60
Call Trace:
<TASK>
raid5_sync_request+0x43d/0x550
md_do_sync+0xb7a/0x2110
md_thread+0x294/0x2b0
kthread+0x147/0x1c0
ret_from_fork+0x59/0x70
ret_from_fork_asm+0x1a/0x30
</TASK>
Root cause is that --revert-reshape update the raid_disks from 5 to 4,
while reshape position is still set, and after reassembling the array,
reshape position will be read from super block, then during reshape the
checking of 'writepos' that is caculated by old reshape position will
fail.
Fix this panic the easy way first, by converting the BUG_ON() to
WARN_ON(), and stop the reshape if checkings fail.
Noted that mdadm must fix --revert-shape as well, and probably md/raid
should enhance metadata validation as well, however this means
reassemble will fail and there must be user tools to fix the wrong
metadata.
Signed-off-by: Yu Kuai <yukuai3(a)huawei.com>
Signed-off-by: Song Liu <song(a)kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-13-yukuai1@huaweicloud.com
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
Signed-off-by: Li Nan <linan122(a)huawei.com>
---
drivers/md/raid5.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 3cb90d7e88d9..126b9ecfe750 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5997,7 +5997,9 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
safepos = conf->reshape_safe;
sector_div(safepos, data_disks);
if (mddev->reshape_backwards) {
- BUG_ON(writepos < reshape_sectors);
+ if (WARN_ON(writepos < reshape_sectors))
+ return MaxSector;
+
writepos -= reshape_sectors;
readpos += reshape_sectors;
safepos += reshape_sectors;
@@ -6015,14 +6017,18 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
* to set 'stripe_addr' which is where we will write to.
*/
if (mddev->reshape_backwards) {
- BUG_ON(conf->reshape_progress == 0);
+ if (WARN_ON(conf->reshape_progress == 0))
+ return MaxSector;
+
stripe_addr = writepos;
- BUG_ON((mddev->dev_sectors &
- ~((sector_t)reshape_sectors - 1))
- - reshape_sectors - stripe_addr
- != sector_nr);
+ if (WARN_ON((mddev->dev_sectors &
+ ~((sector_t)reshape_sectors - 1)) -
+ reshape_sectors - stripe_addr != sector_nr))
+ return MaxSector;
} else {
- BUG_ON(writepos != sector_nr + reshape_sectors);
+ if (WARN_ON(writepos != sector_nr + reshape_sectors))
+ return MaxSector;
+
stripe_addr = sector_nr;
}
--
2.39.2
From: Josef Bacik <josef(a)toxicpanda.com>
stable inclusion
from stable-v5.15.26
commit 6599d5e8bd758d897fd2ef4dc388ae50278b1f7e
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IALPSL
CVE: CVE-2022-48901
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=…
--------------------------------
commit b4be6aefa73c9a6899ef3ba9c5faaa8a66e333ef upstream.
We hit a bug with a recovering relocation on mount for one of our file
systems in production. I reproduced this locally by injecting errors
into snapshot delete with balance running at the same time. This
presented as an error while looking up an extent item
WARNING: CPU: 5 PID: 1501 at fs/btrfs/extent-tree.c:866 lookup_inline_extent_backref+0x647/0x680
CPU: 5 PID: 1501 Comm: btrfs-balance Not tainted 5.16.0-rc8+ #8
RIP: 0010:lookup_inline_extent_backref+0x647/0x680
RSP: 0018:ffffae0a023ab960 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000000
RBP: ffff943fd2a39b60 R08: 0000000000000000 R09: 0000000000000001
R10: 0001434088152de0 R11: 0000000000000000 R12: 0000000001d05000
R13: ffff943fd2a39b60 R14: ffff943fdb96f2a0 R15: ffff9442fc923000
FS: 0000000000000000(0000) GS:ffff944e9eb40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1157b1fca8 CR3: 000000010f092000 CR4: 0000000000350ee0
Call Trace:
<TASK>
insert_inline_extent_backref+0x46/0xd0
__btrfs_inc_extent_ref.isra.0+0x5f/0x200
? btrfs_merge_delayed_refs+0x164/0x190
__btrfs_run_delayed_refs+0x561/0xfa0
? btrfs_search_slot+0x7b4/0xb30
? btrfs_update_root+0x1a9/0x2c0
btrfs_run_delayed_refs+0x73/0x1f0
? btrfs_update_root+0x1a9/0x2c0
btrfs_commit_transaction+0x50/0xa50
? btrfs_update_reloc_root+0x122/0x220
prepare_to_merge+0x29f/0x320
relocate_block_group+0x2b8/0x550
btrfs_relocate_block_group+0x1a6/0x350
btrfs_relocate_chunk+0x27/0xe0
btrfs_balance+0x777/0xe60
balance_kthread+0x35/0x50
? btrfs_balance+0xe60/0xe60
kthread+0x16b/0x190
? set_kthread_struct+0x40/0x40
ret_from_fork+0x22/0x30
</TASK>
Normally snapshot deletion and relocation are excluded from running at
the same time by the fs_info->cleaner_mutex. However if we had a
pending balance waiting to get the ->cleaner_mutex, and a snapshot
deletion was running, and then the box crashed, we would come up in a
state where we have a half deleted snapshot.
Again, in the normal case the snapshot deletion needs to complete before
relocation can start, but in this case relocation could very well start
before the snapshot deletion completes, as we simply add the root to the
dead roots list and wait for the next time the cleaner runs to clean up
the snapshot.
Fix this by setting a bit on the fs_info if we have any DEAD_ROOT's that
had a pending drop_progress key. If they do then we know we were in the
middle of the drop operation and set a flag on the fs_info. Then
balance can wait until this flag is cleared to start up again.
If there are DEAD_ROOT's that don't have a drop_progress set then we're
safe to start balance right away as we'll be properly protected by the
cleaner_mutex.
CC: stable(a)vger.kernel.org # 5.10+
Reviewed-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: Josef Bacik <josef(a)toxicpanda.com>
Reviewed-by: David Sterba <dsterba(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Conflicts:
fs/btrfs/disk-io.c
fs/btrfs/ctree.h
fs/btrfs/transaction.h
[conflicts due to 8cd2908846d1 ("btrfs: clear oneshot options on mount
and remount") not mergered]
Signed-off-by: Long Li <leo.lilong(a)huawei.com>
---
fs/btrfs/ctree.h | 10 ++++++++++
fs/btrfs/disk-io.c | 10 ++++++++++
fs/btrfs/extent-tree.c | 10 ++++++++++
fs/btrfs/relocation.c | 13 +++++++++++++
fs/btrfs/root-tree.c | 15 +++++++++++++++
fs/btrfs/transaction.c | 33 ++++++++++++++++++++++++++++++++-
fs/btrfs/transaction.h | 1 +
7 files changed, 91 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 84ac3642023f..90b46ac13003 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -567,6 +567,9 @@ enum {
/* Indicate that we can't trust the free space tree for caching yet */
BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED,
+
+ /* Indicate we have half completed snapshot deletions pending. */
+ BTRFS_FS_UNFINISHED_DROPS,
};
/*
@@ -1033,8 +1036,15 @@ enum {
BTRFS_ROOT_HAS_LOG_TREE,
/* Qgroup flushing is in progress */
BTRFS_ROOT_QGROUP_FLUSHING,
+ /* This root has a drop operation that was started previously. */
+ BTRFS_ROOT_UNFINISHED_DROP,
};
+static inline void btrfs_wake_unfinished_drop(struct btrfs_fs_info *fs_info)
+{
+ clear_and_wake_up_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags);
+}
+
/*
* Record swapped tree blocks of a subvolume tree for delayed subtree trace
* code. For detail check comment in fs/btrfs/qgroup.c.
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b9a3bdacdede..05bc52003e19 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3427,6 +3427,10 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
}
set_bit(BTRFS_FS_OPEN, &fs_info->flags);
+ /* Kick the cleaner thread so it'll start deleting snapshots. */
+ if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
+ wake_up_process(fs_info->cleaner_kthread);
+
/*
* backuproot only affect mount behavior, and if open_ctree succeeded,
* no need to keep the flag
@@ -4092,6 +4096,12 @@ void __cold close_ctree(struct btrfs_fs_info *fs_info)
*/
kthread_park(fs_info->cleaner_kthread);
+ /*
+ * If we had UNFINISHED_DROPS we could still be processing them, so
+ * clear that bit and wake up relocation so it can stop.
+ */
+ btrfs_wake_unfinished_drop(fs_info);
+
/* wait for the qgroup rescan worker to stop */
btrfs_qgroup_wait_for_completion(fs_info, false);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 284294620e9f..578b217bc4ea 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5353,6 +5353,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
int ret;
int level;
bool root_dropped = false;
+ bool unfinished_drop = false;
btrfs_debug(fs_info, "Drop subvolume %llu", root->root_key.objectid);
@@ -5395,6 +5396,8 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
* already dropped.
*/
set_bit(BTRFS_ROOT_DELETING, &root->state);
+ unfinished_drop = test_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state);
+
if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
level = btrfs_header_level(root->node);
path->nodes[level] = btrfs_lock_root_node(root);
@@ -5571,6 +5574,13 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
kfree(wc);
btrfs_free_path(path);
out:
+ /*
+ * We were an unfinished drop root, check to see if there are any
+ * pending, and if not clear and wake up any waiters.
+ */
+ if (!err && unfinished_drop)
+ btrfs_maybe_wake_unfinished_drop(fs_info);
+
/*
* So if we need to stop dropping the snapshot for whatever reason we
* need to make sure to add it back to the dead root list so that we
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index c21545c5b34b..cf7a8fcea4d6 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -3595,6 +3595,19 @@ int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start)
int rw = 0;
int err = 0;
+ /*
+ * This only gets set if we had a half-deleted snapshot on mount. We
+ * cannot allow relocation to start while we're still trying to clean up
+ * these pending deletions.
+ */
+ ret = wait_on_bit(&fs_info->flags, BTRFS_FS_UNFINISHED_DROPS, TASK_INTERRUPTIBLE);
+ if (ret)
+ return ret;
+
+ /* We may have been woken up by close_ctree, so bail if we're closing. */
+ if (btrfs_fs_closing(fs_info))
+ return -EINTR;
+
bg = btrfs_lookup_block_group(fs_info, group_start);
if (!bg)
return -ENOENT;
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index cd40e7a92552..7bdaccb58ec0 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -280,6 +280,21 @@ int btrfs_find_orphan_roots(struct btrfs_fs_info *fs_info)
WARN_ON(!test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state));
if (btrfs_root_refs(&root->root_item) == 0) {
+ struct btrfs_key drop_key;
+
+ btrfs_disk_key_to_cpu(&drop_key, &root->root_item.drop_progress);
+ /*
+ * If we have a non-zero drop_progress then we know we
+ * made it partly through deleting this snapshot, and
+ * thus we need to make sure we block any balance from
+ * happening until this snapshot is completely dropped.
+ */
+ if (drop_key.objectid != 0 || drop_key.type != 0 ||
+ drop_key.offset != 0) {
+ set_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags);
+ set_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state);
+ }
+
set_bit(BTRFS_ROOT_DEAD_TREE, &root->state);
btrfs_add_dead_root(root);
}
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index a6ddf91d5c40..cf7e8a20bb02 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1294,6 +1294,32 @@ static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans)
return 0;
}
+/*
+ * If we had a pending drop we need to see if there are any others left in our
+ * dead roots list, and if not clear our bit and wake any waiters.
+ */
+void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info)
+{
+ /*
+ * We put the drop in progress roots at the front of the list, so if the
+ * first entry doesn't have UNFINISHED_DROP set we can wake everybody
+ * up.
+ */
+ spin_lock(&fs_info->trans_lock);
+ if (!list_empty(&fs_info->dead_roots)) {
+ struct btrfs_root *root = list_first_entry(&fs_info->dead_roots,
+ struct btrfs_root,
+ root_list);
+ if (test_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state)) {
+ spin_unlock(&fs_info->trans_lock);
+ return;
+ }
+ }
+ spin_unlock(&fs_info->trans_lock);
+
+ btrfs_wake_unfinished_drop(fs_info);
+}
+
/*
* dead roots are old snapshots that need to be deleted. This allocates
* a dirty root struct and adds it into the list of dead roots that need to
@@ -1306,7 +1332,12 @@ void btrfs_add_dead_root(struct btrfs_root *root)
spin_lock(&fs_info->trans_lock);
if (list_empty(&root->root_list)) {
btrfs_grab_root(root);
- list_add_tail(&root->root_list, &fs_info->dead_roots);
+
+ /* We want to process the partially complete drops first. */
+ if (test_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state))
+ list_add(&root->root_list, &fs_info->dead_roots);
+ else
+ list_add_tail(&root->root_list, &fs_info->dead_roots);
}
spin_unlock(&fs_info->trans_lock);
}
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index eb26eb068fe8..0599e3994633 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -216,6 +216,7 @@ int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
void btrfs_add_dead_root(struct btrfs_root *root);
int btrfs_defrag_root(struct btrfs_root *root);
+void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info);
int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
--
2.39.2
From: Josef Bacik <josef(a)toxicpanda.com>
stable inclusion
from stable-v5.15.26
commit 6599d5e8bd758d897fd2ef4dc388ae50278b1f7e
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IALPSL
CVE: CVE-2022-48901
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=…
--------------------------------
commit b4be6aefa73c9a6899ef3ba9c5faaa8a66e333ef upstream.
We hit a bug with a recovering relocation on mount for one of our file
systems in production. I reproduced this locally by injecting errors
into snapshot delete with balance running at the same time. This
presented as an error while looking up an extent item
WARNING: CPU: 5 PID: 1501 at fs/btrfs/extent-tree.c:866 lookup_inline_extent_backref+0x647/0x680
CPU: 5 PID: 1501 Comm: btrfs-balance Not tainted 5.16.0-rc8+ #8
RIP: 0010:lookup_inline_extent_backref+0x647/0x680
RSP: 0018:ffffae0a023ab960 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000000
RBP: ffff943fd2a39b60 R08: 0000000000000000 R09: 0000000000000001
R10: 0001434088152de0 R11: 0000000000000000 R12: 0000000001d05000
R13: ffff943fd2a39b60 R14: ffff943fdb96f2a0 R15: ffff9442fc923000
FS: 0000000000000000(0000) GS:ffff944e9eb40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1157b1fca8 CR3: 000000010f092000 CR4: 0000000000350ee0
Call Trace:
<TASK>
insert_inline_extent_backref+0x46/0xd0
__btrfs_inc_extent_ref.isra.0+0x5f/0x200
? btrfs_merge_delayed_refs+0x164/0x190
__btrfs_run_delayed_refs+0x561/0xfa0
? btrfs_search_slot+0x7b4/0xb30
? btrfs_update_root+0x1a9/0x2c0
btrfs_run_delayed_refs+0x73/0x1f0
? btrfs_update_root+0x1a9/0x2c0
btrfs_commit_transaction+0x50/0xa50
? btrfs_update_reloc_root+0x122/0x220
prepare_to_merge+0x29f/0x320
relocate_block_group+0x2b8/0x550
btrfs_relocate_block_group+0x1a6/0x350
btrfs_relocate_chunk+0x27/0xe0
btrfs_balance+0x777/0xe60
balance_kthread+0x35/0x50
? btrfs_balance+0xe60/0xe60
kthread+0x16b/0x190
? set_kthread_struct+0x40/0x40
ret_from_fork+0x22/0x30
</TASK>
Normally snapshot deletion and relocation are excluded from running at
the same time by the fs_info->cleaner_mutex. However if we had a
pending balance waiting to get the ->cleaner_mutex, and a snapshot
deletion was running, and then the box crashed, we would come up in a
state where we have a half deleted snapshot.
Again, in the normal case the snapshot deletion needs to complete before
relocation can start, but in this case relocation could very well start
before the snapshot deletion completes, as we simply add the root to the
dead roots list and wait for the next time the cleaner runs to clean up
the snapshot.
Fix this by setting a bit on the fs_info if we have any DEAD_ROOT's that
had a pending drop_progress key. If they do then we know we were in the
middle of the drop operation and set a flag on the fs_info. Then
balance can wait until this flag is cleared to start up again.
If there are DEAD_ROOT's that don't have a drop_progress set then we're
safe to start balance right away as we'll be properly protected by the
cleaner_mutex.
CC: stable(a)vger.kernel.org # 5.10+
Reviewed-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: Josef Bacik <josef(a)toxicpanda.com>
Reviewed-by: David Sterba <dsterba(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Conflicts:
fs/btrfs/disk-io.c
fs/btrfs/ctree.h
fs/btrfs/transaction.h
[conflicts due to 8cd2908846d1 ("btrfs: clear oneshot options on mount
and remount") not mergered]
Signed-off-by: Long Li <leo.lilong(a)huawei.com>
---
fs/btrfs/ctree.h | 10 ++++++++++
fs/btrfs/disk-io.c | 10 ++++++++++
fs/btrfs/extent-tree.c | 10 ++++++++++
fs/btrfs/relocation.c | 13 +++++++++++++
fs/btrfs/root-tree.c | 15 +++++++++++++++
fs/btrfs/transaction.c | 33 ++++++++++++++++++++++++++++++++-
fs/btrfs/transaction.h | 1 +
7 files changed, 91 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 482842ac397b..abc1e72a4464 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -565,6 +565,9 @@ enum {
/* Indicate that we can't trust the free space tree for caching yet */
BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED,
+
+ /* Indicate we have half completed snapshot deletions pending. */
+ BTRFS_FS_UNFINISHED_DROPS,
};
/*
@@ -1031,8 +1034,15 @@ enum {
BTRFS_ROOT_HAS_LOG_TREE,
/* Qgroup flushing is in progress */
BTRFS_ROOT_QGROUP_FLUSHING,
+ /* This root has a drop operation that was started previously. */
+ BTRFS_ROOT_UNFINISHED_DROP,
};
+static inline void btrfs_wake_unfinished_drop(struct btrfs_fs_info *fs_info)
+{
+ clear_and_wake_up_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags);
+}
+
/*
* Record swapped tree blocks of a subvolume tree for delayed subtree trace
* code. For detail check comment in fs/btrfs/qgroup.c.
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 707344288b1c..b923011dec85 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3444,6 +3444,10 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
}
set_bit(BTRFS_FS_OPEN, &fs_info->flags);
+ /* Kick the cleaner thread so it'll start deleting snapshots. */
+ if (test_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags))
+ wake_up_process(fs_info->cleaner_kthread);
+
/*
* backuproot only affect mount behavior, and if open_ctree succeeded,
* no need to keep the flag
@@ -4109,6 +4113,12 @@ void __cold close_ctree(struct btrfs_fs_info *fs_info)
*/
kthread_park(fs_info->cleaner_kthread);
+ /*
+ * If we had UNFINISHED_DROPS we could still be processing them, so
+ * clear that bit and wake up relocation so it can stop.
+ */
+ btrfs_wake_unfinished_drop(fs_info);
+
/* wait for the qgroup rescan worker to stop */
btrfs_qgroup_wait_for_completion(fs_info, false);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 3ba43a40032c..1cf787209798 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5365,6 +5365,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
int ret;
int level;
bool root_dropped = false;
+ bool unfinished_drop = false;
btrfs_debug(fs_info, "Drop subvolume %llu", root->root_key.objectid);
@@ -5407,6 +5408,8 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
* already dropped.
*/
set_bit(BTRFS_ROOT_DELETING, &root->state);
+ unfinished_drop = test_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state);
+
if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
level = btrfs_header_level(root->node);
path->nodes[level] = btrfs_lock_root_node(root);
@@ -5583,6 +5586,13 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref, int for_reloc)
kfree(wc);
btrfs_free_path(path);
out:
+ /*
+ * We were an unfinished drop root, check to see if there are any
+ * pending, and if not clear and wake up any waiters.
+ */
+ if (!err && unfinished_drop)
+ btrfs_maybe_wake_unfinished_drop(fs_info);
+
/*
* So if we need to stop dropping the snapshot for whatever reason we
* need to make sure to add it back to the dead root list so that we
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 93db4486a943..bdfa4a93d373 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -3601,6 +3601,19 @@ int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start)
int rw = 0;
int err = 0;
+ /*
+ * This only gets set if we had a half-deleted snapshot on mount. We
+ * cannot allow relocation to start while we're still trying to clean up
+ * these pending deletions.
+ */
+ ret = wait_on_bit(&fs_info->flags, BTRFS_FS_UNFINISHED_DROPS, TASK_INTERRUPTIBLE);
+ if (ret)
+ return ret;
+
+ /* We may have been woken up by close_ctree, so bail if we're closing. */
+ if (btrfs_fs_closing(fs_info))
+ return -EINTR;
+
bg = btrfs_lookup_block_group(fs_info, group_start);
if (!bg)
return -ENOENT;
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index cd40e7a92552..7bdaccb58ec0 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -280,6 +280,21 @@ int btrfs_find_orphan_roots(struct btrfs_fs_info *fs_info)
WARN_ON(!test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state));
if (btrfs_root_refs(&root->root_item) == 0) {
+ struct btrfs_key drop_key;
+
+ btrfs_disk_key_to_cpu(&drop_key, &root->root_item.drop_progress);
+ /*
+ * If we have a non-zero drop_progress then we know we
+ * made it partly through deleting this snapshot, and
+ * thus we need to make sure we block any balance from
+ * happening until this snapshot is completely dropped.
+ */
+ if (drop_key.objectid != 0 || drop_key.type != 0 ||
+ drop_key.offset != 0) {
+ set_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags);
+ set_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state);
+ }
+
set_bit(BTRFS_ROOT_DEAD_TREE, &root->state);
btrfs_add_dead_root(root);
}
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 89117cc2cf05..7d0ea8aeadb0 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1301,6 +1301,32 @@ static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans)
return 0;
}
+/*
+ * If we had a pending drop we need to see if there are any others left in our
+ * dead roots list, and if not clear our bit and wake any waiters.
+ */
+void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info)
+{
+ /*
+ * We put the drop in progress roots at the front of the list, so if the
+ * first entry doesn't have UNFINISHED_DROP set we can wake everybody
+ * up.
+ */
+ spin_lock(&fs_info->trans_lock);
+ if (!list_empty(&fs_info->dead_roots)) {
+ struct btrfs_root *root = list_first_entry(&fs_info->dead_roots,
+ struct btrfs_root,
+ root_list);
+ if (test_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state)) {
+ spin_unlock(&fs_info->trans_lock);
+ return;
+ }
+ }
+ spin_unlock(&fs_info->trans_lock);
+
+ btrfs_wake_unfinished_drop(fs_info);
+}
+
/*
* dead roots are old snapshots that need to be deleted. This allocates
* a dirty root struct and adds it into the list of dead roots that need to
@@ -1313,7 +1339,12 @@ void btrfs_add_dead_root(struct btrfs_root *root)
spin_lock(&fs_info->trans_lock);
if (list_empty(&root->root_list)) {
btrfs_grab_root(root);
- list_add_tail(&root->root_list, &fs_info->dead_roots);
+
+ /* We want to process the partially complete drops first. */
+ if (test_bit(BTRFS_ROOT_UNFINISHED_DROP, &root->state))
+ list_add(&root->root_list, &fs_info->dead_roots);
+ else
+ list_add_tail(&root->root_list, &fs_info->dead_roots);
}
spin_unlock(&fs_info->trans_lock);
}
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index eb26eb068fe8..0599e3994633 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -216,6 +216,7 @@ int btrfs_wait_for_commit(struct btrfs_fs_info *fs_info, u64 transid);
void btrfs_add_dead_root(struct btrfs_root *root);
int btrfs_defrag_root(struct btrfs_root *root);
+void btrfs_maybe_wake_unfinished_drop(struct btrfs_fs_info *fs_info);
int btrfs_clean_one_deleted_snapshot(struct btrfs_root *root);
int btrfs_commit_transaction(struct btrfs_trans_handle *trans);
int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
--
2.39.2