[v4,20/27] btrfs: wait existing extents before truncating
diff mbox series

Message ID 20190823101036.796932-21-naohiro.aota@wdc.com
State New
Headers show
Series
  • btrfs zoned block device support
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Commit Message

Naohiro Aota Aug. 23, 2019, 10:10 a.m. UTC
When truncating a file, file buffers which have already been allocated but
not yet written may be truncated.  Truncating these buffers could cause
breakage of a sequential write pattern in a block group if the truncated
blocks are for example followed by blocks allocated to another file. To
avoid this problem, always wait for write out of all unwritten buffers
before proceeding with the truncate execution.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/inode.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

Patch
diff mbox series

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d7be97c6a069..95f4ce8ac8d0 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -5236,6 +5236,16 @@  static int btrfs_setsize(struct inode *inode, struct iattr *attr)
 		btrfs_end_write_no_snapshotting(root);
 		btrfs_end_transaction(trans);
 	} else {
+		struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+
+		if (btrfs_fs_incompat(fs_info, HMZONED)) {
+			ret = btrfs_wait_ordered_range(
+				inode,
+				ALIGN(newsize, fs_info->sectorsize),
+				(u64)-1);
+			if (ret)
+				return ret;
+		}
 
 		/*
 		 * We're truncating a file that used to have good data down to