Merge remote-tracking branch 'kwolf/tags/for-anthony' into staging

Block patches for 2.0 (flushing block-next)

# gpg: Signature made Fri 29 Nov 2013 08:43:18 AM PST using RSA key ID C88F2FD6
# gpg: Can't check signature: public key not found

# By Peter Lieven (17) and others
# Via Kevin Wolf
* kwolf/tags/for-anthony: (41 commits)
  qemu-iotests: Add sample image and test for VMDK version 3
  vmdk: Allow read only open of VMDK version 3
  qemu-iotests: Filter out 'qemu-io> ' prompt
  qemu-iotests: Filter qemu-io output in 025
  block: Use BDRV_O_NO_BACKING where appropriate
  qemu-iotests: Test snapshot mode
  block: Enable BDRV_O_SNAPSHOT with driver-specific options
  qemu-iotests: Make test case 030, 040 and 055 deterministic
  qemu-iotest: Add pause_drive and resume_drive methods
  blkdebug: add "remove_break" command
  qemu-iotests: Drop local version of cancel_and_wait from 040
  sheepdog: support user-defined redundancy option
  sheepdog: refactor do_sd_create()
  qdict: Optimise qdict_do_flatten()
  qdict: Fix memory leak in qdict_do_flatten()
  MAINTAINERS: add sheepdog development mailing list
  COW: Extend checking allocated bits to beyond one sector
  COW: Speed up writes
  qapi: Change BlockDirtyInfo to list
  block: per caller dirty bitmap
  ...

Message-id: 1385743555-27888-1-git-send-email-kwolf@redhat.com
Signed-off-by: Anthony Liguori <aliguori@amazon.com>

1 files changed, 16 insertions, 4 deletions

diff --git a/qemu-img.c b/qemu-img.c
index b6b5644cb6..dc0c2f0ed3 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -100,8 +100,12 @@ static void help(void)
            "  '-h' with or without a command shows this help and lists the supported formats\n"
            "  '-p' show progress of command (only certain commands)\n"
            "  '-q' use Quiet mode - do not print any output (except errors)\n"
-           "  '-S' indicates the consecutive number of bytes that must contain only zeros\n"
-           "       for qemu-img to create a sparse image during conversion\n"
+           "  '-S' indicates the consecutive number of bytes (defaults to 4k) that must\n"
+           "       contain only zeros for qemu-img to create a sparse image during\n"
+           "       conversion. If the number of bytes is 0, the source will not be scanned for\n"
+           "       unallocated or zero sectors, and the destination image will always be\n"
+           "       fully allocated\n"
+           "       images will always be fully allocated\n"
            "  '--output' takes the format in which the output must be done (human or json)\n"
            "  '-n' skips the target volume creation (useful if the volume is created\n"
            "       prior to running qemu-img)\n"
@@ -1351,7 +1355,7 @@ static int img_convert(int argc, char **argv)
         }
     }
 
-    flags = BDRV_O_RDWR;
+    flags = min_sparse ? (BDRV_O_RDWR | BDRV_O_UNMAP) : BDRV_O_RDWR;
     ret = bdrv_parse_cache_flags(cache, &flags);
     if (ret < 0) {
         error_report("Invalid cache option: %s", cache);
@@ -1465,7 +1469,15 @@ static int img_convert(int argc, char **argv)
         /* signal EOF to align */
         bdrv_write_compressed(out_bs, 0, NULL, 0);
     } else {
-        int has_zero_init = bdrv_has_zero_init(out_bs);
+        int has_zero_init = min_sparse ? bdrv_has_zero_init(out_bs) : 0;
+
+        if (!has_zero_init && bdrv_can_write_zeroes_with_unmap(out_bs)) {
+            ret = bdrv_make_zero(out_bs, BDRV_REQ_MAY_UNMAP);
+            if (ret < 0) {
+                goto out;
+            }
+            has_zero_init = 1;
+        }
 
         sector_num = 0; // total number of sectors converted so far
         nb_sectors = total_sectors - sector_num;