diff options
| -rw-r--r-- | block/qcow2-refcount.c | 72 | ||||
| -rw-r--r-- | block/qcow2.c | 11 | ||||
| -rw-r--r-- | tests/qemu-iotests/026.out | 6 | ||||
| -rw-r--r-- | tests/qemu-iotests/044.out | 2 | ||||
| -rwxr-xr-x | tests/qemu-iotests/080 | 11 | ||||
| -rw-r--r-- | tests/qemu-iotests/080.out | 7 |
6 files changed, 65 insertions, 44 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index e3c7ecdcc9..220b322aa5 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -194,10 +194,11 @@ static int alloc_refcount_block(BlockDriverState *bs, * they can describe them themselves. * * - We need to consider that at this point we are inside update_refcounts - * and doing the initial refcount increase. This means that some clusters - * have already been allocated by the caller, but their refcount isn't - * accurate yet. free_cluster_index tells us where this allocation ends - * as long as we don't overwrite it by freeing clusters. + * and potentially doing an initial refcount increase. This means that + * some clusters have already been allocated by the caller, but their + * refcount isn't accurate yet. If we allocate clusters for metadata, we + * need to return -EAGAIN to signal the caller that it needs to restart + * the search for free clusters. * * - alloc_clusters_noref and qcow2_free_clusters may load a different * refcount block into the cache @@ -282,7 +283,10 @@ static int alloc_refcount_block(BlockDriverState *bs, } s->refcount_table[refcount_table_index] = new_block; - return 0; + + /* The new refcount block may be where the caller intended to put its + * data, so let it restart the search. */ + return -EAGAIN; } ret = qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block); @@ -305,8 +309,7 @@ static int alloc_refcount_block(BlockDriverState *bs, /* Calculate the number of refcount blocks needed so far */ uint64_t refcount_block_clusters = 1 << (s->cluster_bits - REFCOUNT_SHIFT); - uint64_t blocks_used = (s->free_cluster_index + - refcount_block_clusters - 1) / refcount_block_clusters; + uint64_t blocks_used = DIV_ROUND_UP(cluster_index, refcount_block_clusters); /* And now we need at least one block more for the new metadata */ uint64_t table_size = next_refcount_table_size(s, blocks_used + 1); @@ -339,8 +342,6 @@ static int alloc_refcount_block(BlockDriverState *bs, uint16_t *new_blocks = g_malloc0(blocks_clusters * s->cluster_size); uint64_t *new_table = g_malloc0(table_size * sizeof(uint64_t)); - assert(meta_offset >= (s->free_cluster_index * s->cluster_size)); - /* Fill the new refcount table */ memcpy(new_table, s->refcount_table, s->refcount_table_size * sizeof(uint64_t)); @@ -403,18 +404,19 @@ static int alloc_refcount_block(BlockDriverState *bs, s->refcount_table_size = table_size; s->refcount_table_offset = table_offset; - /* Free old table. Remember, we must not change free_cluster_index */ - uint64_t old_free_cluster_index = s->free_cluster_index; + /* Free old table. */ qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t), QCOW2_DISCARD_OTHER); - s->free_cluster_index = old_free_cluster_index; ret = load_refcount_block(bs, new_block, (void**) refcount_block); if (ret < 0) { return ret; } - return 0; + /* If we were trying to do the initial refcount update for some cluster + * allocation, we might have used the same clusters to store newly + * allocated metadata. Make the caller search some new space. */ + return -EAGAIN; fail_table: g_free(new_table); @@ -660,12 +662,15 @@ int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size) int ret; BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC); - offset = alloc_clusters_noref(bs, size); - if (offset < 0) { - return offset; - } + do { + offset = alloc_clusters_noref(bs, size); + if (offset < 0) { + return offset; + } + + ret = update_refcount(bs, offset, size, 1, QCOW2_DISCARD_NEVER); + } while (ret == -EAGAIN); - ret = update_refcount(bs, offset, size, 1, QCOW2_DISCARD_NEVER); if (ret < 0) { return ret; } @@ -678,7 +683,6 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, { BDRVQcowState *s = bs->opaque; uint64_t cluster_index; - uint64_t old_free_cluster_index; uint64_t i; int refcount, ret; @@ -687,30 +691,28 @@ int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, return 0; } - /* Check how many clusters there are free */ - cluster_index = offset >> s->cluster_bits; - for(i = 0; i < nb_clusters; i++) { - refcount = get_refcount(bs, cluster_index++); + do { + /* Check how many clusters there are free */ + cluster_index = offset >> s->cluster_bits; + for(i = 0; i < nb_clusters; i++) { + refcount = get_refcount(bs, cluster_index++); - if (refcount < 0) { - return refcount; - } else if (refcount != 0) { - break; + if (refcount < 0) { + return refcount; + } else if (refcount != 0) { + break; + } } - } - /* And then allocate them */ - old_free_cluster_index = s->free_cluster_index; - s->free_cluster_index = cluster_index + i; + /* And then allocate them */ + ret = update_refcount(bs, offset, i << s->cluster_bits, 1, + QCOW2_DISCARD_NEVER); + } while (ret == -EAGAIN); - ret = update_refcount(bs, offset, i << s->cluster_bits, 1, - QCOW2_DISCARD_NEVER); if (ret < 0) { return ret; } - s->free_cluster_index = old_free_cluster_index; - return i; } diff --git a/block/qcow2.c b/block/qcow2.c index cc1bfebf29..d4d991cbb3 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1602,7 +1602,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, */ BlockDriverState* bs; QCowHeader *header; - uint8_t* refcount_table; + uint64_t* refcount_table; Error *local_err = NULL; int ret; @@ -1654,9 +1654,10 @@ static int qcow2_create2(const char *filename, int64_t total_size, goto out; } - /* Write an empty refcount table */ - refcount_table = g_malloc0(cluster_size); - ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size); + /* Write a refcount table with one refcount block */ + refcount_table = g_malloc0(2 * cluster_size); + refcount_table[0] = cpu_to_be64(2 * cluster_size); + ret = bdrv_pwrite(bs, cluster_size, refcount_table, 2 * cluster_size); g_free(refcount_table); if (ret < 0) { @@ -1681,7 +1682,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, goto out; } - ret = qcow2_alloc_clusters(bs, 2 * cluster_size); + ret = qcow2_alloc_clusters(bs, 3 * cluster_size); if (ret < 0) { error_setg_errno(errp, -ret, "Could not allocate clusters for qcow2 " "header and refcount table"); diff --git a/tests/qemu-iotests/026.out b/tests/qemu-iotests/026.out index 15045799a2..f7c78e712a 100644 --- a/tests/qemu-iotests/026.out +++ b/tests/qemu-iotests/026.out @@ -475,7 +475,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc.write_blocks; errno: 28; imm: off; once: off; write write failed: No space left on device -10 leaked clusters were found on the image. +11 leaked clusters were found on the image. This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 @@ -499,7 +499,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc.write_table; errno: 28; imm: off; once: off; write write failed: No space left on device -10 leaked clusters were found on the image. +11 leaked clusters were found on the image. This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 @@ -523,7 +523,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 Event: refblock_alloc.switch_table; errno: 28; imm: off; once: off; write write failed: No space left on device -10 leaked clusters were found on the image. +11 leaked clusters were found on the image. This means waste of disk space, but no harm to data. Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824 diff --git a/tests/qemu-iotests/044.out b/tests/qemu-iotests/044.out index 5c5aa929fb..4789a5310e 100644 --- a/tests/qemu-iotests/044.out +++ b/tests/qemu-iotests/044.out @@ -1,6 +1,6 @@ No errors were found on the image. 7292415/33554432 = 21.73% allocated, 0.00% fragmented, 0.00% compressed clusters -Image end offset: 4296448000 +Image end offset: 4296152064 . ---------------------------------------------------------------------- Ran 1 tests diff --git a/tests/qemu-iotests/080 b/tests/qemu-iotests/080 index f3091a9377..56f890395c 100755 --- a/tests/qemu-iotests/080 +++ b/tests/qemu-iotests/080 @@ -56,6 +56,8 @@ offset_header_size=100 offset_ext_magic=$header_size offset_ext_size=$((header_size + 4)) +offset_l2_table_0=$((0x40000)) + echo echo "== Huge header size ==" _make_test_img 64M @@ -143,6 +145,15 @@ poke_file "$TEST_IMG" "$offset_backing_file_offset" "\x00\x00\x00\x00\x00\x00\x1 poke_file "$TEST_IMG" "$offset_backing_file_size" "\xff\xff\xff\xff" { $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir +echo +echo "== Invalid L2 entry (huge physical offset) ==" +_make_test_img 64M +{ $QEMU_IO -c "write 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir +poke_file "$TEST_IMG" "$offset_l2_table_0" "\xbf\xff\xff\xff\xff\xff\x00\x00" +{ $QEMU_IMG snapshot -c test $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir +poke_file "$TEST_IMG" "$offset_l2_table_0" "\x80\x00\x00\xff\xff\xff\x00\x00" +{ $QEMU_IMG snapshot -c test $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir + # success, all done echo "*** done" rm -f $seq.full diff --git a/tests/qemu-iotests/080.out b/tests/qemu-iotests/080.out index 8103211064..303d6c3465 100644 --- a/tests/qemu-iotests/080.out +++ b/tests/qemu-iotests/080.out @@ -63,4 +63,11 @@ no file open, try 'help open' Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 qemu-io: can't open device TEST_DIR/t.qcow2: Backing file name too long no file open, try 'help open' + +== Invalid L2 entry (huge physical offset) == +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 +wrote 512/512 bytes at offset 0 +512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +qemu-img: Could not create snapshot 'test': -27 (File too large) +qemu-img: Could not create snapshot 'test': -11 (Resource temporarily unavailable) *** done |