block: add BLOCK_O_CHECK for qemu-img check

Image formats with a dirty bit, like qed and qcow2, repair dirty image
files upon open with BDRV_O_RDWR.  Performing automatic repair when
qemu-img check runs is not ideal because the bdrv_open() call repairs
the image before the actual bdrv_check() call from qemu-img.c.

Fix this "double repair" since it leads to confusing output from
qemu-img check.  Tell the block driver that this image is being opened
just for bdrv_check().  This skips automatic repair and qemu-img.c can
invoke it manually with bdrv_check().

Update the golden output for qemu-iotests 039 to reflect the new
qemu-img check output.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/block.h b/block.h
index 650d872f461fe88f6c6ff17c7331cbab0f7bc708..2e2be110710a05462ef55cd3f22308da2e9d427f 100644 (file)
--- a/block.h
+++ b/block.h
@@ -79,6 +79,7 @@ typedef struct BlockDevOps {
 #define BDRV_O_NO_FLUSH    0x0200 /* disable flushing on this disk */
 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
 #define BDRV_O_INCOMING    0x0800  /* consistency hint for incoming migration */
+#define BDRV_O_CHECK       0x1000  /* open solely for consistency check */
 
 #define BDRV_O_CACHE_MASK  (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH)
 

diff --git a/block/qcow2.c b/block/qcow2.c
index 5896fd6d9ca8c754b7c96bece3e5159523a08502..8f183f146554cf3287649bddfe63b031afb0ecfa 100644 (file)
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -484,8 +484,8 @@ static int qcow2_open(BlockDriverState *bs, int flags)
     qemu_co_mutex_init(&s->lock);
 
     /* Repair image if dirty */
-    if ((s->incompatible_features & QCOW2_INCOMPAT_DIRTY) &&
-        !bs->read_only) {
+    if (!(flags & BDRV_O_CHECK) && !bs->read_only &&
+        (s->incompatible_features & QCOW2_INCOMPAT_DIRTY)) {
         BdrvCheckResult result = {0};
 
         ret = qcow2_check(bs, &result, BDRV_FIX_ERRORS);

diff --git a/block/qed.c b/block/qed.c
index 226545d8e703bc81bffb198695af42013c854aca..a02dbfd72de50bee77146535f0e9f704a0c02e10 100644 (file)
--- a/block/qed.c
+++ b/block/qed.c
@@ -477,7 +477,7 @@ static int bdrv_qed_open(BlockDriverState *bs, int flags)
     }
 
     /* If image was not closed cleanly, check consistency */
-    if (s->header.features & QED_F_NEED_CHECK) {
+    if (!(flags & BDRV_O_CHECK) && (s->header.features & QED_F_NEED_CHECK)) {
         /* Read-only images cannot be fixed.  There is no risk of corruption
          * since write operations are not possible.  Therefore, allow
          * potentially inconsistent images to be opened read-only.  This can

diff --git a/qemu-img.c b/qemu-img.c
index 94a31ad9f0aecaa3761d342e75b8594157808f0f..b41e670a6184e85acbf6f4567db1349e6511eb5b 100644 (file)
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -379,7 +379,7 @@ static int img_check(int argc, char **argv)
     BlockDriverState *bs;
     BdrvCheckResult result;
     int fix = 0;
-    int flags = BDRV_O_FLAGS;
+    int flags = BDRV_O_FLAGS | BDRV_O_CHECK;
 
     fmt = NULL;
     for(;;) {

diff --git a/tests/qemu-iotests/039.out b/tests/qemu-iotests/039.out
index 155a05e1093835e7db170dc9d1222721e1363dba..cb510d6716636f525e16b2577f537ed3a59a5323 100644 (file)
--- a/tests/qemu-iotests/039.out
+++ b/tests/qemu-iotests/039.out
@@ -26,6 +26,12 @@ incompatible_features     0x1
 == Repairing the image file must succeed ==
 ERROR OFLAG_COPIED: offset=8000000000050000 refcount=0
 Repairing cluster 5 refcount=0 reference=1
+The following inconsistencies were found and repaired:
+
+    0 leaked clusters
+    1 corruptions
+
+Double checking the fixed image now...
 No errors were found on the image.
 incompatible_features     0x0