[PATCH 2/5] Btrfs: treat RWF_{,D}SYNC writes as sync for CRCs

[Omar Sandoval <osandov@osandov.com>]

From: Omar Sandoval <osandov@fb.com>

In btrfs_file_write_iter(), we treat a write as synchrononous if the
file is marked as synchronous. However, with pwritev2(), a write with
RWF_SYNC or RWF_DSYNC is also synchronous even if the file isn't by
default. Make sure we bump the sync_writers counter in that case, too,
so that we'll do the CRCs synchronously.

Signed-off-by: Omar Sandoval <osandov@fb.com>
---
 fs/btrfs/file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 4393b6b24e02..27223753da7b 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1882,7 +1882,7 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
 	u64 start_pos;
 	u64 end_pos;
 	ssize_t num_written = 0;
-	bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host);
+	bool sync = iocb->ki_flags & IOCB_DSYNC;
 	ssize_t err;
 	loff_t pos;
 	size_t count;
-- 
2.17.1