[Qemu-devel] [PATCH 5/8] block/raw-posix: refactor handle_aiocb_write_zeroes a bit

["Denis V. Lunev" <den@openvz.org>]

move code dealing with a block device to a separate function. This will
allow to implement additional processing for an ordinary files.

Pls note, that xfs_code has been moved before checking for
s->has_write_zeroes as xfs_write_zeroes does not touch this flag inside.
This makes code a bit more consistent.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Peter Lieven <pl@kamp.de>
---
 block/raw-posix.c | 60 +++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 38 insertions(+), 22 deletions(-)

diff --git a/block/raw-posix.c b/block/raw-posix.c
index 25a6947..7866d31 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -915,46 +915,62 @@ static int do_fallocate(int fd, int mode, off_t offset, off_t len)
 }
 #endif
 
-static ssize_t handle_aiocb_write_zeroes(RawPosixAIOData *aiocb)
+static ssize_t handle_aiocb_write_zeroes_block(RawPosixAIOData *aiocb)
 {
     int ret = -EOPNOTSUPP;
     BDRVRawState *s = aiocb->bs->opaque;
 
-    if (s->has_write_zeroes == 0) {
+    if (!s->has_write_zeroes) {
         return -ENOTSUP;
     }
 
-    if (aiocb->aio_type & QEMU_AIO_BLKDEV) {
 #ifdef BLKZEROOUT
-        do {
-            uint64_t range[2] = { aiocb->aio_offset, aiocb->aio_nbytes };
-            if (ioctl(aiocb->aio_fildes, BLKZEROOUT, range) == 0) {
-                return 0;
-            }
-        } while (errno == EINTR);
-
-        ret = -errno;
-#endif
-    } else {
-#ifdef CONFIG_XFS
-        if (s->is_xfs) {
-            return xfs_write_zeroes(s, aiocb->aio_offset, aiocb->aio_nbytes);
+    do {
+        uint64_t range[2] = { aiocb->aio_offset, aiocb->aio_nbytes };
+        if (ioctl(aiocb->aio_fildes, BLKZEROOUT, range) == 0) {
+            return 0;
         }
-#endif
+    } while (errno == EINTR);
 
-#ifdef CONFIG_FALLOCATE_ZERO_RANGE
-        ret = do_fallocate(s->fd, FALLOC_FL_ZERO_RANGE,
-                           aiocb->aio_offset, aiocb->aio_nbytes);
+    ret = translate_err(-errno);
 #endif
-    }
 
-    ret = translate_err(ret);
     if (ret == -ENOTSUP) {
         s->has_write_zeroes = false;
     }
     return ret;
 }
 
+static ssize_t handle_aiocb_write_zeroes(RawPosixAIOData *aiocb)
+{
+    BDRVRawState *s;
+
+    if (aiocb->aio_type & QEMU_AIO_BLKDEV) {
+        return handle_aiocb_write_zeroes_block(aiocb);
+    }
+
+#ifdef CONFIG_XFS
+    if (s->is_xfs) {
+        return xfs_write_zeroes(s, aiocb->aio_offset, aiocb->aio_nbytes);
+    }
+#endif
+
+    s = aiocb->bs->opaque;
+
+#ifdef CONFIG_FALLOCATE_ZERO_RANGE
+    if (s->has_write_zeroes) {
+        int ret = do_fallocate(s->fd, FALLOC_FL_ZERO_RANGE,
+                               aiocb->aio_offset, aiocb->aio_nbytes);
+        if (ret == 0 && ret != -ENOTSUP) {
+            return ret;
+        }
+    }
+#endif
+
+    s->has_write_zeroes = false;
+    return -ENOTSUP;
+}
+
 static ssize_t handle_aiocb_discard(RawPosixAIOData *aiocb)
 {
     int ret = -EOPNOTSUPP;
-- 
1.9.1