block: consistently use bdrv_is_read_only()

It's better to use accessor function instead of bs->read_only directly.
In some places use bdrv_is_writable() instead of
checking both BDRV_O_RDWR set and BDRV_O_INACTIVE not set.

In bdrv_open_common() it's a bit strange to add one more variable, but
we are going to drop bs->read_only in the next patch, so new ro local
variable substitutes it here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210527154056.70294-2-vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/block.c b/block.c
index ef13076c4c..33e99d0c9e 100644
--- a/block.c
+++ b/block.c
@@ -1720,6 +1720,7 @@ static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file,
     QemuOpts *opts;
     BlockDriver *drv;
     Error *local_err = NULL;
+    bool ro;
 
     assert(bs->file == NULL);
     assert(options != NULL && bs->options != options);
@@ -1772,15 +1773,17 @@ static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file,
 
     bs->read_only = !(bs->open_flags & BDRV_O_RDWR);
 
-    if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) {
-        if (!bs->read_only && bdrv_is_whitelisted(drv, true)) {
+    ro = bdrv_is_read_only(bs);
+
+    if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, ro)) {
+        if (!ro && bdrv_is_whitelisted(drv, true)) {
             ret = bdrv_apply_auto_read_only(bs, NULL, NULL);
         } else {
             ret = -ENOTSUP;
         }
         if (ret < 0) {
             error_setg(errp,
-                       !bs->read_only && bdrv_is_whitelisted(drv, true)
+                       !ro && bdrv_is_whitelisted(drv, true)
                        ? "Driver '%s' can only be used for read-only devices"
                        : "Driver '%s' is not whitelisted",
                        drv->format_name);
@@ -1792,7 +1795,7 @@ static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file,
     assert(qatomic_read(&bs->copy_on_read) == 0);
 
     if (bs->open_flags & BDRV_O_COPY_ON_READ) {
-        if (!bs->read_only) {
+        if (!ro) {
             bdrv_enable_copy_on_read(bs);
         } else {
             error_setg(errp, "Can't use copy-on-read on read-only device");