In fuse_open(), set these flags:
- direct_io: We probably actually don't want to have the host page cache
be used for our exports. QEMU block exports are supposed to represent
the image as-is (and thus potentially changing).
This causes a change in iotest 308's reference output.
- parallel_direct_writes: We can (now) cope with parallel writes, so we
should set this flag. For some reason, it doesn't seem to make an
actual performance difference with libfuse, but it does make a
difference without it, so let's set it.
(See "fuse: Copy write buffer content before polling" for further
discussion.)
Signed-off-by: Hanna Czenczek <hre...@redhat.com>
---
block/export/fuse.c | 2 ++
tests/qemu-iotests/308.out | 2 +-
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/block/export/fuse.c b/block/export/fuse.c
index 0d20995a0e..2df6297d61 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -576,6 +576,8 @@ static void fuse_setattr(fuse_req_t req, fuse_ino_t inode,
struct stat *statbuf,
static void fuse_open(fuse_req_t req, fuse_ino_t inode,
struct fuse_file_info *fi)
{
+ fi->direct_io = true;
+ fi->parallel_direct_writes = true;
fuse_reply_open(req, fi);
}
diff --git a/tests/qemu-iotests/308.out b/tests/qemu-iotests/308.out
index aa96faab6d..2d7a38d63d 100644
--- a/tests/qemu-iotests/308.out
+++ b/tests/qemu-iotests/308.out
@@ -131,7 +131,7 @@ wrote 65536/65536 bytes at offset 1048576
--- Try growing non-growable export ---
(OK: Lengths of export and original are the same)
-dd: error writing 'TEST_DIR/t.IMGFMT.fuse': Input/output error
+dd: error writing 'TEST_DIR/t.IMGFMT.fuse': No space left on device
1+0 records in
0+0 records out
--
2.48.1
