This is a note to let you know that I've just added the patch titled
btrfs: zoned: only allow one process to add pages to a relocation inode
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
btrfs-zoned-only-allow-one-process-to-add-pages-to-a-relocation-inode.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Fri Nov 19 01:33:42 PM CET 2021
From: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Date: Thu, 18 Nov 2021 17:58:15 +0900
Subject: btrfs: zoned: only allow one process to add pages to a relocation inode
To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: linux-btrfs@xxxxxxxxxxxxxxx, stable@xxxxxxxxxxxxxxx, Naohiro Aota <naohiro.aota@xxxxxxx>, David Sterba <dsterba@xxxxxxxx>, Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Message-ID: <c2c15d9992727dc6473d3dedb3d863874a3d3222.1637225333.git.johannes.thumshirn@xxxxxxx>
From: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
commit 35156d852762b58855f513b4f8bb7f32d69dc9c5 upstream
Don't allow more than one process to add pages to a relocation inode on
a zoned filesystem, otherwise we cannot guarantee the sequential write
rule once we're filling preallocated extents on a zoned filesystem.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/extent_io.c | 11 +++++++++++
1 file changed, 11 insertions(+)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -5120,6 +5120,9 @@ int extent_write_locked_range(struct ino
int extent_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
+ struct inode *inode = mapping->host;
+ const bool data_reloc = btrfs_is_data_reloc_root(BTRFS_I(inode)->root);
+ const bool zoned = btrfs_is_zoned(BTRFS_I(inode)->root->fs_info);
int ret = 0;
struct extent_page_data epd = {
.bio_ctrl = { 0 },
@@ -5127,7 +5130,15 @@ int extent_writepages(struct address_spa
.sync_io = wbc->sync_mode == WB_SYNC_ALL,
};
+ /*
+ * Allow only a single thread to do the reloc work in zoned mode to
+ * protect the write pointer updates.
+ */
+ if (data_reloc && zoned)
+ btrfs_inode_lock(inode, 0);
ret = extent_write_cache_pages(mapping, wbc, &epd);
+ if (data_reloc && zoned)
+ btrfs_inode_unlock(inode, 0);
ASSERT(ret <= 0);
if (ret < 0) {
end_write_bio(&epd, ret);
Patches currently in stable-queue which might be from johannes.thumshirn@xxxxxxx are
queue-5.15/btrfs-zoned-add-a-dedicated-data-relocation-block-group.patch
queue-5.15/btrfs-check-for-relocation-inodes-on-zoned-btrfs-in-should_nocow.patch
queue-5.15/btrfs-zoned-use-regular-writes-for-relocation.patch
queue-5.15/btrfs-introduce-btrfs_is_data_reloc_root.patch
queue-5.15/btrfs-zoned-allow-preallocation-for-relocation-inodes.patch
queue-5.15/btrfs-zoned-only-allow-one-process-to-add-pages-to-a-relocation-inode.patch
