From: Johannes Thumshirn Date: Thu, 18 Nov 2021 08:58:15 +0000 (+0900) Subject: btrfs: zoned: only allow one process to add pages to a relocation inode X-Git-Tag: accepted/tizen/unified/20230118.172025~5131 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f716e9827838f1554a770deec16c2968b9445b50;p=platform%2Fkernel%2Flinux-rpi.git btrfs: zoned: only allow one process to add pages to a relocation inode 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 Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Johannes Thumshirn Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index aaddd72..a40fb9c 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -5120,6 +5120,9 @@ int extent_write_locked_range(struct inode *inode, u64 start, u64 end, 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_space *mapping, .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);