diff options
| -rw-r--r-- | block/qcow2.c | 47 | ||||
| -rw-r--r-- | block/qcow2.h | 7 | ||||
| -rw-r--r-- | docs/specs/qcow2.txt | 7 | ||||
| -rw-r--r-- | tests/qemu-iotests/031.out | 12 | ||||
| -rw-r--r-- | tests/qemu-iotests/036.out | 2 |
5 files changed, 66 insertions, 9 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 5e5f4132d9..fe915681b2 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -272,6 +272,37 @@ static int qcow2_mark_clean(BlockDriverState *bs) return 0; } +/* + * Marks the image as corrupt. + */ +int qcow2_mark_corrupt(BlockDriverState *bs) +{ + BDRVQcowState *s = bs->opaque; + + s->incompatible_features |= QCOW2_INCOMPAT_CORRUPT; + return qcow2_update_header(bs); +} + +/* + * Marks the image as consistent, i.e., unsets the corrupt bit, and flushes + * before if necessary. + */ +int qcow2_mark_consistent(BlockDriverState *bs) +{ + BDRVQcowState *s = bs->opaque; + + if (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT) { + int ret = bdrv_flush(bs); + if (ret < 0) { + return ret; + } + + s->incompatible_features &= ~QCOW2_INCOMPAT_CORRUPT; + return qcow2_update_header(bs); + } + return 0; +} + static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result, BdrvCheckMode fix) { @@ -402,6 +433,17 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags) goto fail; } + if (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT) { + /* Corrupt images may not be written to unless they are being repaired + */ + if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_CHECK)) { + error_report("qcow2: Image is corrupt; cannot be opened " + "read/write."); + ret = -EACCES; + goto fail; + } + } + /* Check support for various header values */ if (header.refcount_order != 4) { report_unsupported(bs, "%d bit reference counts", @@ -1130,6 +1172,11 @@ int qcow2_update_header(BlockDriverState *bs) .name = "dirty bit", }, { + .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, + .bit = QCOW2_INCOMPAT_CORRUPT_BITNR, + .name = "corrupt bit", + }, + { .type = QCOW2_FEAT_TYPE_COMPATIBLE, .bit = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR, .name = "lazy refcounts", diff --git a/block/qcow2.h b/block/qcow2.h index 365a17e4e8..32ecb338ab 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -119,9 +119,12 @@ enum { /* Incompatible feature bits */ enum { QCOW2_INCOMPAT_DIRTY_BITNR = 0, + QCOW2_INCOMPAT_CORRUPT_BITNR = 1, QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR, + QCOW2_INCOMPAT_CORRUPT = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR, - QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY, + QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY + | QCOW2_INCOMPAT_CORRUPT, }; /* Compatible feature bits */ @@ -361,6 +364,8 @@ int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov, int64_t sector_num, int nb_sectors); int qcow2_mark_dirty(BlockDriverState *bs); +int qcow2_mark_corrupt(BlockDriverState *bs); +int qcow2_mark_consistent(BlockDriverState *bs); int qcow2_update_header(BlockDriverState *bs); /* qcow2-refcount.c functions */ diff --git a/docs/specs/qcow2.txt b/docs/specs/qcow2.txt index 36a559d886..33eca360cc 100644 --- a/docs/specs/qcow2.txt +++ b/docs/specs/qcow2.txt @@ -80,7 +80,12 @@ in the description of a field. tables to repair refcounts before accessing the image. - Bits 1-63: Reserved (set to 0) + Bit 1: Corrupt bit. If this bit is set then any data + structure may be corrupt and the image must not + be written to (unless for regaining + consistency). + + Bits 2-63: Reserved (set to 0) 80 - 87: compatible_features Bitmask of compatible features. An implementation can diff --git a/tests/qemu-iotests/031.out b/tests/qemu-iotests/031.out index 796c993df2..a94334478e 100644 --- a/tests/qemu-iotests/031.out +++ b/tests/qemu-iotests/031.out @@ -54,7 +54,7 @@ header_length 72 Header extension: magic 0x6803f857 -length 96 +length 144 data <binary> Header extension: @@ -68,7 +68,7 @@ No errors were found on the image. magic 0x514649fb version 2 -backing_file_offset 0xf8 +backing_file_offset 0x128 backing_file_size 0x17 cluster_bits 16 size 67108864 @@ -92,7 +92,7 @@ data 'host_device' Header extension: magic 0x6803f857 -length 96 +length 144 data <binary> Header extension: @@ -155,7 +155,7 @@ header_length 104 Header extension: magic 0x6803f857 -length 96 +length 144 data <binary> Header extension: @@ -169,7 +169,7 @@ No errors were found on the image. magic 0x514649fb version 3 -backing_file_offset 0x118 +backing_file_offset 0x148 backing_file_size 0x17 cluster_bits 16 size 67108864 @@ -193,7 +193,7 @@ data 'host_device' Header extension: magic 0x6803f857 -length 96 +length 144 data <binary> Header extension: diff --git a/tests/qemu-iotests/036.out b/tests/qemu-iotests/036.out index 063ca22d66..55a3e6e441 100644 --- a/tests/qemu-iotests/036.out +++ b/tests/qemu-iotests/036.out @@ -46,7 +46,7 @@ header_length 104 Header extension: magic 0x6803f857 -length 96 +length 144 data <binary> *** done |