[Qemu-devel] [PATCH v3 06/19] block: do not parse BDRV_O_CACHE_WB in block drivers

[Jeff Cody <jcody@redhat.com>]

Block drivers should ignore BDRV_O_CACHE_WB in .bdrv_open flags,
and in the bs->open_flags.

This patch removes the code, leaving the behaviour behind as if
BDRV_O_CACHE_WB was set.

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/iscsi.c     |  4 ----
 block/raw-posix.c |  3 ---
 block/raw-win32.c |  3 ---
 block/rbd.c       |  6 ------
 block/sheepdog.c  | 14 ++++++--------
 5 files changed, 6 insertions(+), 24 deletions(-)

diff --git a/block/iscsi.c b/block/iscsi.c
index 0b96165..70cf700 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -268,10 +268,6 @@ iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num,
     acb->task->xfer_dir = SCSI_XFER_WRITE;
     acb->task->cdb_size = 16;
     acb->task->cdb[0] = 0x8a;
-    if (!(bs->open_flags & BDRV_O_CACHE_WB)) {
-        /* set FUA on writes when cache mode is write through */
-        acb->task->cdb[1] |= 0x04;
-    }
     lba = sector_qemu2lun(sector_num, iscsilun);
     *(uint32_t *)&acb->task->cdb[2]  = htonl(lba >> 32);
     *(uint32_t *)&acb->task->cdb[6]  = htonl(lba & 0xffffffff);
diff --git a/block/raw-posix.c b/block/raw-posix.c
index 7d3ac9d..4a1047c 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -202,9 +202,6 @@ static void raw_parse_flags(int bdrv_flags, int *open_flags)
     if ((bdrv_flags & BDRV_O_NOCACHE)) {
         *open_flags |= O_DIRECT;
     }
-    if (!(bdrv_flags & BDRV_O_CACHE_WB)) {
-        *open_flags |= O_DSYNC;
-    }
 }
 
 static int raw_set_aio(void **aio_ctx, int *use_aio, int bdrv_flags)
diff --git a/block/raw-win32.c b/block/raw-win32.c
index 335c06a..78c8306 100644
--- a/block/raw-win32.c
+++ b/block/raw-win32.c
@@ -92,9 +92,6 @@ static void raw_parse_flags(int flags, int *access_flags, DWORD *overlapped)
     if (flags & BDRV_O_NOCACHE) {
         *overlapped |= FILE_FLAG_NO_BUFFERING;
     }
-    if (!(flags & BDRV_O_CACHE_WB)) {
-        *overlapped |= FILE_FLAG_WRITE_THROUGH;
-    }
 }
 
 static int raw_open(BlockDriverState *bs, const char *filename, int flags)
diff --git a/block/rbd.c b/block/rbd.c
index 5a0f79f..015a9db 100644
--- a/block/rbd.c
+++ b/block/rbd.c
@@ -487,12 +487,6 @@ static int qemu_rbd_open(BlockDriverState *bs, const char *filename, int flags)
         rados_conf_set(s->cluster, "rbd_cache", "false");
     } else {
         rados_conf_set(s->cluster, "rbd_cache", "true");
-        if (!(flags & BDRV_O_CACHE_WB)) {
-            r = rados_conf_set(s->cluster, "rbd_cache_max_dirty", "0");
-            if (r < 0) {
-                rados_conf_set(s->cluster, "rbd_cache", "false");
-            }
-        }
     }
 
     if (strstr(conf, "conf=") == NULL) {
diff --git a/block/sheepdog.c b/block/sheepdog.c
index df4f441..5b553db 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -1114,14 +1114,12 @@ static int sd_open(BlockDriverState *bs, const char *filename, int flags)
         goto out;
     }
 
-    if (flags & BDRV_O_CACHE_WB) {
-        s->cache_enabled = 1;
-        s->flush_fd = connect_to_sdog(s->addr, s->port);
-        if (s->flush_fd < 0) {
-            error_report("failed to connect");
-            ret = s->flush_fd;
-            goto out;
-        }
+    s->cache_enabled = 1;
+    s->flush_fd = connect_to_sdog(s->addr, s->port);
+    if (s->flush_fd < 0) {
+        error_report("failed to connect");
+        ret = s->flush_fd;
+        goto out;
     }
 
     if (snapid || tag[0] != '\0') {
-- 
1.7.11.4