* [Qemu-devel] [PATCH 1/4] qcow2: Split out refcount handling
2009-05-28 14:07 [Qemu-devel] [PATCH 0/4] Split qcow2 driver Kevin Wolf
@ 2009-05-28 14:07 ` Kevin Wolf
2009-05-28 14:07 ` [Qemu-devel] [PATCH 2/4] qcow2: Split out guest cluster functions Kevin Wolf
` (3 subsequent siblings)
4 siblings, 0 replies; 9+ messages in thread
From: Kevin Wolf @ 2009-05-28 14:07 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf
qcow2-refcount.c contains all functions which are related to cluster
allocation and management in the image file. A large part of this is the
reference counting of these clusters.
Also a header file qcow2.h is introduced which will contain the interface of
the split qcow2 modules.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
Makefile | 3 +-
block/qcow2-refcount.c | 808 ++++++++++++++++++++++++++++++++++++++++++++
block/qcow2.c | 871 +-----------------------------------------------
block/qcow2.h | 154 +++++++++
4 files changed, 966 insertions(+), 870 deletions(-)
create mode 100644 block/qcow2-refcount.c
create mode 100644 block/qcow2.h
diff --git a/Makefile b/Makefile
index d7b9985..5a0fdbe 100644
--- a/Makefile
+++ b/Makefile
@@ -68,7 +68,8 @@ recurse-all: $(SUBDIR_RULES)
BLOCK_OBJS=cutils.o cache-utils.o qemu-malloc.o qemu-option.o module.o
BLOCK_OBJS+=block/cow.o block/qcow.o aes.o block/vmdk.o block/cloop.o
BLOCK_OBJS+=block/dmg.o block/bochs.o block/vpc.o block/vvfat.o
-BLOCK_OBJS+=block/qcow2.o block/parallels.o block/nbd.o
+BLOCK_OBJS+=block/qcow2.o block/qcow2-refcount.o
+BLOCK_OBJS+=block/parallels.o block/nbd.o
BLOCK_OBJS+=nbd.o block.o aio.o
ifdef CONFIG_WIN32
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
new file mode 100644
index 0000000..b70afe9
--- /dev/null
+++ b/block/qcow2-refcount.c
@@ -0,0 +1,808 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu-common.h"
+#include "block_int.h"
+#include "block/qcow2.h"
+
+static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size);
+static int update_refcount(BlockDriverState *bs,
+ int64_t offset, int64_t length,
+ int addend);
+
+/*********************************************************/
+/* refcount handling */
+
+int refcount_init(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ int ret, refcount_table_size2, i;
+
+ s->refcount_block_cache = qemu_malloc(s->cluster_size);
+ refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
+ s->refcount_table = qemu_malloc(refcount_table_size2);
+ if (s->refcount_table_size > 0) {
+ ret = bdrv_pread(s->hd, s->refcount_table_offset,
+ s->refcount_table, refcount_table_size2);
+ if (ret != refcount_table_size2)
+ goto fail;
+ for(i = 0; i < s->refcount_table_size; i++)
+ be64_to_cpus(&s->refcount_table[i]);
+ }
+ return 0;
+ fail:
+ return -ENOMEM;
+}
+
+void refcount_close(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ qemu_free(s->refcount_block_cache);
+ qemu_free(s->refcount_table);
+}
+
+
+static int load_refcount_block(BlockDriverState *bs,
+ int64_t refcount_block_offset)
+{
+ BDRVQcowState *s = bs->opaque;
+ int ret;
+ ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache,
+ s->cluster_size);
+ if (ret != s->cluster_size)
+ return -EIO;
+ s->refcount_block_cache_offset = refcount_block_offset;
+ return 0;
+}
+
+static int get_refcount(BlockDriverState *bs, int64_t cluster_index)
+{
+ BDRVQcowState *s = bs->opaque;
+ int refcount_table_index, block_index;
+ int64_t refcount_block_offset;
+
+ refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
+ if (refcount_table_index >= s->refcount_table_size)
+ return 0;
+ refcount_block_offset = s->refcount_table[refcount_table_index];
+ if (!refcount_block_offset)
+ return 0;
+ if (refcount_block_offset != s->refcount_block_cache_offset) {
+ /* better than nothing: return allocated if read error */
+ if (load_refcount_block(bs, refcount_block_offset) < 0)
+ return 1;
+ }
+ block_index = cluster_index &
+ ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
+ return be16_to_cpu(s->refcount_block_cache[block_index]);
+}
+
+static int grow_refcount_table(BlockDriverState *bs, int min_size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int new_table_size, new_table_size2, refcount_table_clusters, i, ret;
+ uint64_t *new_table;
+ int64_t table_offset;
+ uint8_t data[12];
+ int old_table_size;
+ int64_t old_table_offset;
+
+ if (min_size <= s->refcount_table_size)
+ return 0;
+ /* compute new table size */
+ refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3);
+ for(;;) {
+ if (refcount_table_clusters == 0) {
+ refcount_table_clusters = 1;
+ } else {
+ refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2;
+ }
+ new_table_size = refcount_table_clusters << (s->cluster_bits - 3);
+ if (min_size <= new_table_size)
+ break;
+ }
+#ifdef DEBUG_ALLOC2
+ printf("grow_refcount_table from %d to %d\n",
+ s->refcount_table_size,
+ new_table_size);
+#endif
+ new_table_size2 = new_table_size * sizeof(uint64_t);
+ new_table = qemu_mallocz(new_table_size2);
+ memcpy(new_table, s->refcount_table,
+ s->refcount_table_size * sizeof(uint64_t));
+ for(i = 0; i < s->refcount_table_size; i++)
+ cpu_to_be64s(&new_table[i]);
+ /* Note: we cannot update the refcount now to avoid recursion */
+ table_offset = alloc_clusters_noref(bs, new_table_size2);
+ ret = bdrv_pwrite(s->hd, table_offset, new_table, new_table_size2);
+ if (ret != new_table_size2)
+ goto fail;
+ for(i = 0; i < s->refcount_table_size; i++)
+ be64_to_cpus(&new_table[i]);
+
+ cpu_to_be64w((uint64_t*)data, table_offset);
+ cpu_to_be32w((uint32_t*)(data + 8), refcount_table_clusters);
+ if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset),
+ data, sizeof(data)) != sizeof(data))
+ goto fail;
+ qemu_free(s->refcount_table);
+ old_table_offset = s->refcount_table_offset;
+ old_table_size = s->refcount_table_size;
+ s->refcount_table = new_table;
+ s->refcount_table_size = new_table_size;
+ s->refcount_table_offset = table_offset;
+
+ update_refcount(bs, table_offset, new_table_size2, 1);
+ free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
+ return 0;
+ fail:
+ free_clusters(bs, table_offset, new_table_size2);
+ qemu_free(new_table);
+ return -EIO;
+}
+
+
+static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
+{
+ BDRVQcowState *s = bs->opaque;
+ int64_t offset, refcount_block_offset;
+ int ret, refcount_table_index;
+ uint64_t data64;
+
+ /* Find L1 index and grow refcount table if needed */
+ refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
+ if (refcount_table_index >= s->refcount_table_size) {
+ ret = grow_refcount_table(bs, refcount_table_index + 1);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Load or allocate the refcount block */
+ refcount_block_offset = s->refcount_table[refcount_table_index];
+ if (!refcount_block_offset) {
+ /* create a new refcount block */
+ /* Note: we cannot update the refcount now to avoid recursion */
+ offset = alloc_clusters_noref(bs, s->cluster_size);
+ memset(s->refcount_block_cache, 0, s->cluster_size);
+ ret = bdrv_pwrite(s->hd, offset, s->refcount_block_cache, s->cluster_size);
+ if (ret != s->cluster_size)
+ return -EINVAL;
+ s->refcount_table[refcount_table_index] = offset;
+ data64 = cpu_to_be64(offset);
+ ret = bdrv_pwrite(s->hd, s->refcount_table_offset +
+ refcount_table_index * sizeof(uint64_t),
+ &data64, sizeof(data64));
+ if (ret != sizeof(data64))
+ return -EINVAL;
+
+ refcount_block_offset = offset;
+ s->refcount_block_cache_offset = offset;
+ update_refcount(bs, offset, s->cluster_size, 1);
+ } else {
+ if (refcount_block_offset != s->refcount_block_cache_offset) {
+ if (load_refcount_block(bs, refcount_block_offset) < 0)
+ return -EIO;
+ }
+ }
+
+ return refcount_block_offset;
+}
+
+/* XXX: cache several refcount block clusters ? */
+static int update_refcount(BlockDriverState *bs,
+ int64_t offset, int64_t length,
+ int addend)
+{
+ BDRVQcowState *s = bs->opaque;
+ int64_t start, last, cluster_offset;
+ int64_t refcount_block_offset = 0;
+ int64_t table_index = -1, old_table_index;
+ int first_index = -1, last_index = -1;
+
+#ifdef DEBUG_ALLOC2
+ printf("update_refcount: offset=%lld size=%lld addend=%d\n",
+ offset, length, addend);
+#endif
+ if (length <= 0)
+ return -EINVAL;
+ start = offset & ~(s->cluster_size - 1);
+ last = (offset + length - 1) & ~(s->cluster_size - 1);
+ for(cluster_offset = start; cluster_offset <= last;
+ cluster_offset += s->cluster_size)
+ {
+ int block_index, refcount;
+ int64_t cluster_index = cluster_offset >> s->cluster_bits;
+
+ /* Only write refcount block to disk when we are done with it */
+ old_table_index = table_index;
+ table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
+ if ((old_table_index >= 0) && (table_index != old_table_index)) {
+ size_t size = (last_index - first_index + 1) << REFCOUNT_SHIFT;
+ if (bdrv_pwrite(s->hd,
+ refcount_block_offset + (first_index << REFCOUNT_SHIFT),
+ &s->refcount_block_cache[first_index], size) != size)
+ {
+ return -EIO;
+ }
+
+ first_index = -1;
+ last_index = -1;
+ }
+
+ /* Load the refcount block and allocate it if needed */
+ refcount_block_offset = alloc_refcount_block(bs, cluster_index);
+ if (refcount_block_offset < 0) {
+ return refcount_block_offset;
+ }
+
+ /* we can update the count and save it */
+ block_index = cluster_index &
+ ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
+ if (first_index == -1 || block_index < first_index) {
+ first_index = block_index;
+ }
+ if (block_index > last_index) {
+ last_index = block_index;
+ }
+
+ refcount = be16_to_cpu(s->refcount_block_cache[block_index]);
+ refcount += addend;
+ if (refcount < 0 || refcount > 0xffff)
+ return -EINVAL;
+ if (refcount == 0 && cluster_index < s->free_cluster_index) {
+ s->free_cluster_index = cluster_index;
+ }
+ s->refcount_block_cache[block_index] = cpu_to_be16(refcount);
+ }
+
+ /* Write last changed block to disk */
+ if (refcount_block_offset != 0) {
+ size_t size = (last_index - first_index + 1) << REFCOUNT_SHIFT;
+ if (bdrv_pwrite(s->hd,
+ refcount_block_offset + (first_index << REFCOUNT_SHIFT),
+ &s->refcount_block_cache[first_index], size) != size)
+ {
+ return -EIO;
+ }
+ }
+
+ return 0;
+}
+
+/* addend must be 1 or -1 */
+static int update_cluster_refcount(BlockDriverState *bs,
+ int64_t cluster_index,
+ int addend)
+{
+ BDRVQcowState *s = bs->opaque;
+ int ret;
+
+ ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
+ if (ret < 0) {
+ return ret;
+ }
+
+ return get_refcount(bs, cluster_index);
+}
+
+
+
+/*********************************************************/
+/* cluster allocation functions */
+
+
+
+/* return < 0 if error */
+static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int i, nb_clusters;
+
+ nb_clusters = size_to_clusters(s, size);
+retry:
+ for(i = 0; i < nb_clusters; i++) {
+ int64_t i = s->free_cluster_index++;
+ if (get_refcount(bs, i) != 0)
+ goto retry;
+ }
+#ifdef DEBUG_ALLOC2
+ printf("alloc_clusters: size=%lld -> %lld\n",
+ size,
+ (s->free_cluster_index - nb_clusters) << s->cluster_bits);
+#endif
+ return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
+}
+
+int64_t alloc_clusters(BlockDriverState *bs, int64_t size)
+{
+ int64_t offset;
+
+ offset = alloc_clusters_noref(bs, size);
+ update_refcount(bs, offset, size, 1);
+ return offset;
+}
+
+/* only used to allocate compressed sectors. We try to allocate
+ contiguous sectors. size must be <= cluster_size */
+int64_t alloc_bytes(BlockDriverState *bs, int size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int64_t offset, cluster_offset;
+ int free_in_cluster;
+
+ assert(size > 0 && size <= s->cluster_size);
+ if (s->free_byte_offset == 0) {
+ s->free_byte_offset = alloc_clusters(bs, s->cluster_size);
+ }
+ redo:
+ free_in_cluster = s->cluster_size -
+ (s->free_byte_offset & (s->cluster_size - 1));
+ if (size <= free_in_cluster) {
+ /* enough space in current cluster */
+ offset = s->free_byte_offset;
+ s->free_byte_offset += size;
+ free_in_cluster -= size;
+ if (free_in_cluster == 0)
+ s->free_byte_offset = 0;
+ if ((offset & (s->cluster_size - 1)) != 0)
+ update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
+ } else {
+ offset = alloc_clusters(bs, s->cluster_size);
+ cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
+ if ((cluster_offset + s->cluster_size) == offset) {
+ /* we are lucky: contiguous data */
+ offset = s->free_byte_offset;
+ update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
+ s->free_byte_offset += size;
+ } else {
+ s->free_byte_offset = offset;
+ goto redo;
+ }
+ }
+ return offset;
+}
+
+void free_clusters(BlockDriverState *bs,
+ int64_t offset, int64_t size)
+{
+ update_refcount(bs, offset, size, -1);
+}
+
+
+
+/*********************************************************/
+/* snapshots and image creation */
+
+
+
+void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size)
+{
+ int refcount;
+ int64_t start, last, cluster_offset;
+ uint16_t *p;
+
+ start = offset & ~(s->cluster_size - 1);
+ last = (offset + size - 1) & ~(s->cluster_size - 1);
+ for(cluster_offset = start; cluster_offset <= last;
+ cluster_offset += s->cluster_size) {
+ p = &s->refcount_block[cluster_offset >> s->cluster_bits];
+ refcount = be16_to_cpu(*p);
+ refcount++;
+ *p = cpu_to_be16(refcount);
+ }
+}
+
+/* update the refcounts of snapshots and the copied flag */
+int update_snapshot_refcount(BlockDriverState *bs,
+ int64_t l1_table_offset,
+ int l1_size,
+ int addend)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated;
+ int64_t old_offset, old_l2_offset;
+ int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount;
+
+ l2_cache_reset(bs);
+
+ l2_table = NULL;
+ l1_table = NULL;
+ l1_size2 = l1_size * sizeof(uint64_t);
+ l1_allocated = 0;
+ if (l1_table_offset != s->l1_table_offset) {
+ l1_table = qemu_malloc(l1_size2);
+ l1_allocated = 1;
+ if (bdrv_pread(s->hd, l1_table_offset,
+ l1_table, l1_size2) != l1_size2)
+ goto fail;
+ for(i = 0;i < l1_size; i++)
+ be64_to_cpus(&l1_table[i]);
+ } else {
+ assert(l1_size == s->l1_size);
+ l1_table = s->l1_table;
+ l1_allocated = 0;
+ }
+
+ l2_size = s->l2_size * sizeof(uint64_t);
+ l2_table = qemu_malloc(l2_size);
+ l1_modified = 0;
+ for(i = 0; i < l1_size; i++) {
+ l2_offset = l1_table[i];
+ if (l2_offset) {
+ old_l2_offset = l2_offset;
+ l2_offset &= ~QCOW_OFLAG_COPIED;
+ l2_modified = 0;
+ if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
+ goto fail;
+ for(j = 0; j < s->l2_size; j++) {
+ offset = be64_to_cpu(l2_table[j]);
+ if (offset != 0) {
+ old_offset = offset;
+ offset &= ~QCOW_OFLAG_COPIED;
+ if (offset & QCOW_OFLAG_COMPRESSED) {
+ nb_csectors = ((offset >> s->csize_shift) &
+ s->csize_mask) + 1;
+ if (addend != 0)
+ update_refcount(bs, (offset & s->cluster_offset_mask) & ~511,
+ nb_csectors * 512, addend);
+ /* compressed clusters are never modified */
+ refcount = 2;
+ } else {
+ if (addend != 0) {
+ refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend);
+ } else {
+ refcount = get_refcount(bs, offset >> s->cluster_bits);
+ }
+ }
+
+ if (refcount == 1) {
+ offset |= QCOW_OFLAG_COPIED;
+ }
+ if (offset != old_offset) {
+ l2_table[j] = cpu_to_be64(offset);
+ l2_modified = 1;
+ }
+ }
+ }
+ if (l2_modified) {
+ if (bdrv_pwrite(s->hd,
+ l2_offset, l2_table, l2_size) != l2_size)
+ goto fail;
+ }
+
+ if (addend != 0) {
+ refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend);
+ } else {
+ refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
+ }
+ if (refcount == 1) {
+ l2_offset |= QCOW_OFLAG_COPIED;
+ }
+ if (l2_offset != old_l2_offset) {
+ l1_table[i] = l2_offset;
+ l1_modified = 1;
+ }
+ }
+ }
+ if (l1_modified) {
+ for(i = 0; i < l1_size; i++)
+ cpu_to_be64s(&l1_table[i]);
+ if (bdrv_pwrite(s->hd, l1_table_offset, l1_table,
+ l1_size2) != l1_size2)
+ goto fail;
+ for(i = 0; i < l1_size; i++)
+ be64_to_cpus(&l1_table[i]);
+ }
+ if (l1_allocated)
+ qemu_free(l1_table);
+ qemu_free(l2_table);
+ return 0;
+ fail:
+ if (l1_allocated)
+ qemu_free(l1_table);
+ qemu_free(l2_table);
+ return -EIO;
+}
+
+
+
+
+/*********************************************************/
+/* refcount checking functions */
+
+
+
+/*
+ * Increases the refcount for a range of clusters in a given refcount table.
+ * This is used to construct a temporary refcount table out of L1 and L2 tables
+ * which can be compared the the refcount table saved in the image.
+ *
+ * Returns the number of errors in the image that were found
+ */
+static int inc_refcounts(BlockDriverState *bs,
+ uint16_t *refcount_table,
+ int refcount_table_size,
+ int64_t offset, int64_t size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int64_t start, last, cluster_offset;
+ int k;
+ int errors = 0;
+
+ if (size <= 0)
+ return 0;
+
+ start = offset & ~(s->cluster_size - 1);
+ last = (offset + size - 1) & ~(s->cluster_size - 1);
+ for(cluster_offset = start; cluster_offset <= last;
+ cluster_offset += s->cluster_size) {
+ k = cluster_offset >> s->cluster_bits;
+ if (k < 0 || k >= refcount_table_size) {
+ fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n",
+ cluster_offset);
+ errors++;
+ } else {
+ if (++refcount_table[k] == 0) {
+ fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
+ "\n", cluster_offset);
+ errors++;
+ }
+ }
+ }
+
+ return errors;
+}
+
+/*
+ * Increases the refcount in the given refcount table for the all clusters
+ * referenced in the L2 table. While doing so, performs some checks on L2
+ * entries.
+ *
+ * Returns the number of errors found by the checks or -errno if an internal
+ * error occurred.
+ */
+static int check_refcounts_l2(BlockDriverState *bs,
+ uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
+ int check_copied)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint64_t *l2_table, offset;
+ int i, l2_size, nb_csectors, refcount;
+ int errors = 0;
+
+ /* Read L2 table from disk */
+ l2_size = s->l2_size * sizeof(uint64_t);
+ l2_table = qemu_malloc(l2_size);
+
+ if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
+ goto fail;
+
+ /* Do the actual checks */
+ for(i = 0; i < s->l2_size; i++) {
+ offset = be64_to_cpu(l2_table[i]);
+ if (offset != 0) {
+ if (offset & QCOW_OFLAG_COMPRESSED) {
+ /* Compressed clusters don't have QCOW_OFLAG_COPIED */
+ if (offset & QCOW_OFLAG_COPIED) {
+ fprintf(stderr, "ERROR: cluster %" PRId64 ": "
+ "copied flag must never be set for compressed "
+ "clusters\n", offset >> s->cluster_bits);
+ offset &= ~QCOW_OFLAG_COPIED;
+ errors++;
+ }
+
+ /* Mark cluster as used */
+ nb_csectors = ((offset >> s->csize_shift) &
+ s->csize_mask) + 1;
+ offset &= s->cluster_offset_mask;
+ errors += inc_refcounts(bs, refcount_table,
+ refcount_table_size,
+ offset & ~511, nb_csectors * 512);
+ } else {
+ /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
+ if (check_copied) {
+ uint64_t entry = offset;
+ offset &= ~QCOW_OFLAG_COPIED;
+ refcount = get_refcount(bs, offset >> s->cluster_bits);
+ if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) {
+ fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
+ PRIx64 " refcount=%d\n", entry, refcount);
+ errors++;
+ }
+ }
+
+ /* Mark cluster as used */
+ offset &= ~QCOW_OFLAG_COPIED;
+ errors += inc_refcounts(bs, refcount_table,
+ refcount_table_size,
+ offset, s->cluster_size);
+
+ /* Correct offsets are cluster aligned */
+ if (offset & (s->cluster_size - 1)) {
+ fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not "
+ "properly aligned; L2 entry corrupted.\n", offset);
+ errors++;
+ }
+ }
+ }
+ }
+
+ qemu_free(l2_table);
+ return errors;
+
+fail:
+ fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
+ qemu_free(l2_table);
+ return -EIO;
+}
+
+/*
+ * Increases the refcount for the L1 table, its L2 tables and all referenced
+ * clusters in the given refcount table. While doing so, performs some checks
+ * on L1 and L2 entries.
+ *
+ * Returns the number of errors found by the checks or -errno if an internal
+ * error occurred.
+ */
+static int check_refcounts_l1(BlockDriverState *bs,
+ uint16_t *refcount_table,
+ int refcount_table_size,
+ int64_t l1_table_offset, int l1_size,
+ int check_copied)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint64_t *l1_table, l2_offset, l1_size2;
+ int i, refcount, ret;
+ int errors = 0;
+
+ l1_size2 = l1_size * sizeof(uint64_t);
+
+ /* Mark L1 table as used */
+ errors += inc_refcounts(bs, refcount_table, refcount_table_size,
+ l1_table_offset, l1_size2);
+
+ /* Read L1 table entries from disk */
+ l1_table = qemu_malloc(l1_size2);
+ if (bdrv_pread(s->hd, l1_table_offset,
+ l1_table, l1_size2) != l1_size2)
+ goto fail;
+ for(i = 0;i < l1_size; i++)
+ be64_to_cpus(&l1_table[i]);
+
+ /* Do the actual checks */
+ for(i = 0; i < l1_size; i++) {
+ l2_offset = l1_table[i];
+ if (l2_offset) {
+ /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
+ if (check_copied) {
+ refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED)
+ >> s->cluster_bits);
+ if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) {
+ fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
+ " refcount=%d\n", l2_offset, refcount);
+ errors++;
+ }
+ }
+
+ /* Mark L2 table as used */
+ l2_offset &= ~QCOW_OFLAG_COPIED;
+ errors += inc_refcounts(bs, refcount_table,
+ refcount_table_size,
+ l2_offset,
+ s->cluster_size);
+
+ /* L2 tables are cluster aligned */
+ if (l2_offset & (s->cluster_size - 1)) {
+ fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not "
+ "cluster aligned; L1 entry corrupted\n", l2_offset);
+ errors++;
+ }
+
+ /* Process and check L2 entries */
+ ret = check_refcounts_l2(bs, refcount_table, refcount_table_size,
+ l2_offset, check_copied);
+ if (ret < 0) {
+ goto fail;
+ }
+ errors += ret;
+ }
+ }
+ qemu_free(l1_table);
+ return errors;
+
+fail:
+ fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
+ qemu_free(l1_table);
+ return -EIO;
+}
+
+/*
+ * Checks an image for refcount consistency.
+ *
+ * Returns 0 if no errors are found, the number of errors in case the image is
+ * detected as corrupted, and -errno when an internal error occured.
+ */
+int check_refcounts(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ int64_t size;
+ int nb_clusters, refcount1, refcount2, i;
+ QCowSnapshot *sn;
+ uint16_t *refcount_table;
+ int ret, errors = 0;
+
+ size = bdrv_getlength(s->hd);
+ nb_clusters = size_to_clusters(s, size);
+ refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
+
+ /* header */
+ errors += inc_refcounts(bs, refcount_table, nb_clusters,
+ 0, s->cluster_size);
+
+ /* current L1 table */
+ ret = check_refcounts_l1(bs, refcount_table, nb_clusters,
+ s->l1_table_offset, s->l1_size, 1);
+ if (ret < 0) {
+ return ret;
+ }
+ errors += ret;
+
+ /* snapshots */
+ for(i = 0; i < s->nb_snapshots; i++) {
+ sn = s->snapshots + i;
+ check_refcounts_l1(bs, refcount_table, nb_clusters,
+ sn->l1_table_offset, sn->l1_size, 0);
+ }
+ errors += inc_refcounts(bs, refcount_table, nb_clusters,
+ s->snapshots_offset, s->snapshots_size);
+
+ /* refcount data */
+ errors += inc_refcounts(bs, refcount_table, nb_clusters,
+ s->refcount_table_offset,
+ s->refcount_table_size * sizeof(uint64_t));
+ for(i = 0; i < s->refcount_table_size; i++) {
+ int64_t offset;
+ offset = s->refcount_table[i];
+ if (offset != 0) {
+ errors += inc_refcounts(bs, refcount_table, nb_clusters,
+ offset, s->cluster_size);
+ }
+ }
+
+ /* compare ref counts */
+ for(i = 0; i < nb_clusters; i++) {
+ refcount1 = get_refcount(bs, i);
+ refcount2 = refcount_table[i];
+ if (refcount1 != refcount2) {
+ fprintf(stderr, "ERROR cluster %d refcount=%d reference=%d\n",
+ i, refcount1, refcount2);
+ errors++;
+ }
+ }
+
+ qemu_free(refcount_table);
+
+ return errors;
+}
+
diff --git a/block/qcow2.c b/block/qcow2.c
index d1611d1..f9ff44f 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -26,6 +26,7 @@
#include "module.h"
#include <zlib.h>
#include "aes.h"
+#include "block/qcow2.h"
/*
Differences with QCOW:
@@ -47,40 +48,6 @@
//#define DEBUG_ALLOC2
//#define DEBUG_EXT
-#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
-#define QCOW_VERSION 2
-
-#define QCOW_CRYPT_NONE 0
-#define QCOW_CRYPT_AES 1
-
-#define QCOW_MAX_CRYPT_CLUSTERS 32
-
-/* indicate that the refcount of the referenced cluster is exactly one. */
-#define QCOW_OFLAG_COPIED (1LL << 63)
-/* indicate that the cluster is compressed (they never have the copied flag) */
-#define QCOW_OFLAG_COMPRESSED (1LL << 62)
-
-#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */
-
-#define MIN_CLUSTER_BITS 9
-#define MAX_CLUSTER_BITS 16
-
-typedef struct QCowHeader {
- uint32_t magic;
- uint32_t version;
- uint64_t backing_file_offset;
- uint32_t backing_file_size;
- uint32_t cluster_bits;
- uint64_t size; /* in bytes */
- uint32_t crypt_method;
- uint32_t l1_size; /* XXX: save number of clusters instead ? */
- uint64_t l1_table_offset;
- uint64_t refcount_table_offset;
- uint32_t refcount_table_clusters;
- uint32_t nb_snapshots;
- uint64_t snapshots_offset;
-} QCowHeader;
-
typedef struct {
uint32_t magic;
@@ -110,77 +77,12 @@ typedef struct __attribute__((packed)) QCowSnapshotHeader {
/* name follows */
} QCowSnapshotHeader;
-#define L2_CACHE_SIZE 16
-
-typedef struct QCowSnapshot {
- uint64_t l1_table_offset;
- uint32_t l1_size;
- char *id_str;
- char *name;
- uint32_t vm_state_size;
- uint32_t date_sec;
- uint32_t date_nsec;
- uint64_t vm_clock_nsec;
-} QCowSnapshot;
-
-typedef struct BDRVQcowState {
- BlockDriverState *hd;
- int cluster_bits;
- int cluster_size;
- int cluster_sectors;
- int l2_bits;
- int l2_size;
- int l1_size;
- int l1_vm_state_index;
- int csize_shift;
- int csize_mask;
- uint64_t cluster_offset_mask;
- uint64_t l1_table_offset;
- uint64_t *l1_table;
- uint64_t *l2_cache;
- uint64_t l2_cache_offsets[L2_CACHE_SIZE];
- uint32_t l2_cache_counts[L2_CACHE_SIZE];
- uint8_t *cluster_cache;
- uint8_t *cluster_data;
- uint64_t cluster_cache_offset;
-
- uint64_t *refcount_table;
- uint64_t refcount_table_offset;
- uint32_t refcount_table_size;
- uint64_t refcount_block_cache_offset;
- uint16_t *refcount_block_cache;
- int64_t free_cluster_index;
- int64_t free_byte_offset;
-
- uint32_t crypt_method; /* current crypt method, 0 if no key yet */
- uint32_t crypt_method_header;
- AES_KEY aes_encrypt_key;
- AES_KEY aes_decrypt_key;
- uint64_t snapshots_offset;
- int snapshots_size;
- int nb_snapshots;
- QCowSnapshot *snapshots;
-} BDRVQcowState;
static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
static int qcow_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors);
static int qcow_read_snapshots(BlockDriverState *bs);
static void qcow_free_snapshots(BlockDriverState *bs);
-static int refcount_init(BlockDriverState *bs);
-static void refcount_close(BlockDriverState *bs);
-static int get_refcount(BlockDriverState *bs, int64_t cluster_index);
-static int update_cluster_refcount(BlockDriverState *bs,
- int64_t cluster_index,
- int addend);
-static int update_refcount(BlockDriverState *bs,
- int64_t offset, int64_t length,
- int addend);
-static int64_t alloc_clusters(BlockDriverState *bs, int64_t size);
-static int64_t alloc_bytes(BlockDriverState *bs, int size);
-static void free_clusters(BlockDriverState *bs,
- int64_t offset, int64_t size);
-static int check_refcounts(BlockDriverState *bs);
static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
{
@@ -482,7 +384,7 @@ static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
return 0;
}
-static void l2_cache_reset(BlockDriverState *bs)
+void l2_cache_reset(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
@@ -691,11 +593,6 @@ static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index)
return l2_table;
}
-static int size_to_clusters(BDRVQcowState *s, int64_t size)
-{
- return (size + (s->cluster_size - 1)) >> s->cluster_bits;
-}
-
static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size,
uint64_t *l2_table, uint64_t start, uint64_t mask)
{
@@ -1522,35 +1419,6 @@ static void qcow_close(BlockDriverState *bs)
bdrv_delete(s->hd);
}
-/* XXX: use std qcow open function ? */
-typedef struct QCowCreateState {
- int cluster_size;
- int cluster_bits;
- uint16_t *refcount_block;
- uint64_t *refcount_table;
- int64_t l1_table_offset;
- int64_t refcount_table_offset;
- int64_t refcount_block_offset;
-} QCowCreateState;
-
-static void create_refcount_update(QCowCreateState *s,
- int64_t offset, int64_t size)
-{
- int refcount;
- int64_t start, last, cluster_offset;
- uint16_t *p;
-
- start = offset & ~(s->cluster_size - 1);
- last = (offset + size - 1) & ~(s->cluster_size - 1);
- for(cluster_offset = start; cluster_offset <= last;
- cluster_offset += s->cluster_size) {
- p = &s->refcount_block[cluster_offset >> s->cluster_bits];
- refcount = be16_to_cpu(*p);
- refcount++;
- *p = cpu_to_be16(refcount);
- }
-}
-
static int get_bits_from_size(size_t size)
{
int res = 0;
@@ -1834,117 +1702,6 @@ static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
/*********************************************************/
/* snapshot support */
-/* update the refcounts of snapshots and the copied flag */
-static int update_snapshot_refcount(BlockDriverState *bs,
- int64_t l1_table_offset,
- int l1_size,
- int addend)
-{
- BDRVQcowState *s = bs->opaque;
- uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated;
- int64_t old_offset, old_l2_offset;
- int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount;
-
- l2_cache_reset(bs);
-
- l2_table = NULL;
- l1_table = NULL;
- l1_size2 = l1_size * sizeof(uint64_t);
- l1_allocated = 0;
- if (l1_table_offset != s->l1_table_offset) {
- l1_table = qemu_malloc(l1_size2);
- l1_allocated = 1;
- if (bdrv_pread(s->hd, l1_table_offset,
- l1_table, l1_size2) != l1_size2)
- goto fail;
- for(i = 0;i < l1_size; i++)
- be64_to_cpus(&l1_table[i]);
- } else {
- assert(l1_size == s->l1_size);
- l1_table = s->l1_table;
- l1_allocated = 0;
- }
-
- l2_size = s->l2_size * sizeof(uint64_t);
- l2_table = qemu_malloc(l2_size);
- l1_modified = 0;
- for(i = 0; i < l1_size; i++) {
- l2_offset = l1_table[i];
- if (l2_offset) {
- old_l2_offset = l2_offset;
- l2_offset &= ~QCOW_OFLAG_COPIED;
- l2_modified = 0;
- if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
- goto fail;
- for(j = 0; j < s->l2_size; j++) {
- offset = be64_to_cpu(l2_table[j]);
- if (offset != 0) {
- old_offset = offset;
- offset &= ~QCOW_OFLAG_COPIED;
- if (offset & QCOW_OFLAG_COMPRESSED) {
- nb_csectors = ((offset >> s->csize_shift) &
- s->csize_mask) + 1;
- if (addend != 0)
- update_refcount(bs, (offset & s->cluster_offset_mask) & ~511,
- nb_csectors * 512, addend);
- /* compressed clusters are never modified */
- refcount = 2;
- } else {
- if (addend != 0) {
- refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend);
- } else {
- refcount = get_refcount(bs, offset >> s->cluster_bits);
- }
- }
-
- if (refcount == 1) {
- offset |= QCOW_OFLAG_COPIED;
- }
- if (offset != old_offset) {
- l2_table[j] = cpu_to_be64(offset);
- l2_modified = 1;
- }
- }
- }
- if (l2_modified) {
- if (bdrv_pwrite(s->hd,
- l2_offset, l2_table, l2_size) != l2_size)
- goto fail;
- }
-
- if (addend != 0) {
- refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend);
- } else {
- refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
- }
- if (refcount == 1) {
- l2_offset |= QCOW_OFLAG_COPIED;
- }
- if (l2_offset != old_l2_offset) {
- l1_table[i] = l2_offset;
- l1_modified = 1;
- }
- }
- }
- if (l1_modified) {
- for(i = 0; i < l1_size; i++)
- cpu_to_be64s(&l1_table[i]);
- if (bdrv_pwrite(s->hd, l1_table_offset, l1_table,
- l1_size2) != l1_size2)
- goto fail;
- for(i = 0; i < l1_size; i++)
- be64_to_cpus(&l1_table[i]);
- }
- if (l1_allocated)
- qemu_free(l1_table);
- qemu_free(l2_table);
- return 0;
- fail:
- if (l1_allocated)
- qemu_free(l1_table);
- qemu_free(l2_table);
- return -EIO;
-}
static void qcow_free_snapshots(BlockDriverState *bs)
{
@@ -2306,630 +2063,6 @@ static int qcow_snapshot_list(BlockDriverState *bs,
return s->nb_snapshots;
}
-/*********************************************************/
-/* refcount handling */
-
-static int refcount_init(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- int ret, refcount_table_size2, i;
-
- s->refcount_block_cache = qemu_malloc(s->cluster_size);
- refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
- s->refcount_table = qemu_malloc(refcount_table_size2);
- if (s->refcount_table_size > 0) {
- ret = bdrv_pread(s->hd, s->refcount_table_offset,
- s->refcount_table, refcount_table_size2);
- if (ret != refcount_table_size2)
- goto fail;
- for(i = 0; i < s->refcount_table_size; i++)
- be64_to_cpus(&s->refcount_table[i]);
- }
- return 0;
- fail:
- return -ENOMEM;
-}
-
-static void refcount_close(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- qemu_free(s->refcount_block_cache);
- qemu_free(s->refcount_table);
-}
-
-
-static int load_refcount_block(BlockDriverState *bs,
- int64_t refcount_block_offset)
-{
- BDRVQcowState *s = bs->opaque;
- int ret;
- ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache,
- s->cluster_size);
- if (ret != s->cluster_size)
- return -EIO;
- s->refcount_block_cache_offset = refcount_block_offset;
- return 0;
-}
-
-static int get_refcount(BlockDriverState *bs, int64_t cluster_index)
-{
- BDRVQcowState *s = bs->opaque;
- int refcount_table_index, block_index;
- int64_t refcount_block_offset;
-
- refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
- if (refcount_table_index >= s->refcount_table_size)
- return 0;
- refcount_block_offset = s->refcount_table[refcount_table_index];
- if (!refcount_block_offset)
- return 0;
- if (refcount_block_offset != s->refcount_block_cache_offset) {
- /* better than nothing: return allocated if read error */
- if (load_refcount_block(bs, refcount_block_offset) < 0)
- return 1;
- }
- block_index = cluster_index &
- ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
- return be16_to_cpu(s->refcount_block_cache[block_index]);
-}
-
-/* return < 0 if error */
-static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
-{
- BDRVQcowState *s = bs->opaque;
- int i, nb_clusters;
-
- nb_clusters = size_to_clusters(s, size);
-retry:
- for(i = 0; i < nb_clusters; i++) {
- int64_t i = s->free_cluster_index++;
- if (get_refcount(bs, i) != 0)
- goto retry;
- }
-#ifdef DEBUG_ALLOC2
- printf("alloc_clusters: size=%lld -> %lld\n",
- size,
- (s->free_cluster_index - nb_clusters) << s->cluster_bits);
-#endif
- return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
-}
-
-static int64_t alloc_clusters(BlockDriverState *bs, int64_t size)
-{
- int64_t offset;
-
- offset = alloc_clusters_noref(bs, size);
- update_refcount(bs, offset, size, 1);
- return offset;
-}
-
-/* only used to allocate compressed sectors. We try to allocate
- contiguous sectors. size must be <= cluster_size */
-static int64_t alloc_bytes(BlockDriverState *bs, int size)
-{
- BDRVQcowState *s = bs->opaque;
- int64_t offset, cluster_offset;
- int free_in_cluster;
-
- assert(size > 0 && size <= s->cluster_size);
- if (s->free_byte_offset == 0) {
- s->free_byte_offset = alloc_clusters(bs, s->cluster_size);
- }
- redo:
- free_in_cluster = s->cluster_size -
- (s->free_byte_offset & (s->cluster_size - 1));
- if (size <= free_in_cluster) {
- /* enough space in current cluster */
- offset = s->free_byte_offset;
- s->free_byte_offset += size;
- free_in_cluster -= size;
- if (free_in_cluster == 0)
- s->free_byte_offset = 0;
- if ((offset & (s->cluster_size - 1)) != 0)
- update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
- } else {
- offset = alloc_clusters(bs, s->cluster_size);
- cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
- if ((cluster_offset + s->cluster_size) == offset) {
- /* we are lucky: contiguous data */
- offset = s->free_byte_offset;
- update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
- s->free_byte_offset += size;
- } else {
- s->free_byte_offset = offset;
- goto redo;
- }
- }
- return offset;
-}
-
-static void free_clusters(BlockDriverState *bs,
- int64_t offset, int64_t size)
-{
- update_refcount(bs, offset, size, -1);
-}
-
-static int grow_refcount_table(BlockDriverState *bs, int min_size)
-{
- BDRVQcowState *s = bs->opaque;
- int new_table_size, new_table_size2, refcount_table_clusters, i, ret;
- uint64_t *new_table;
- int64_t table_offset;
- uint8_t data[12];
- int old_table_size;
- int64_t old_table_offset;
-
- if (min_size <= s->refcount_table_size)
- return 0;
- /* compute new table size */
- refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3);
- for(;;) {
- if (refcount_table_clusters == 0) {
- refcount_table_clusters = 1;
- } else {
- refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2;
- }
- new_table_size = refcount_table_clusters << (s->cluster_bits - 3);
- if (min_size <= new_table_size)
- break;
- }
-#ifdef DEBUG_ALLOC2
- printf("grow_refcount_table from %d to %d\n",
- s->refcount_table_size,
- new_table_size);
-#endif
- new_table_size2 = new_table_size * sizeof(uint64_t);
- new_table = qemu_mallocz(new_table_size2);
- memcpy(new_table, s->refcount_table,
- s->refcount_table_size * sizeof(uint64_t));
- for(i = 0; i < s->refcount_table_size; i++)
- cpu_to_be64s(&new_table[i]);
- /* Note: we cannot update the refcount now to avoid recursion */
- table_offset = alloc_clusters_noref(bs, new_table_size2);
- ret = bdrv_pwrite(s->hd, table_offset, new_table, new_table_size2);
- if (ret != new_table_size2)
- goto fail;
- for(i = 0; i < s->refcount_table_size; i++)
- be64_to_cpus(&new_table[i]);
-
- cpu_to_be64w((uint64_t*)data, table_offset);
- cpu_to_be32w((uint32_t*)(data + 8), refcount_table_clusters);
- if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset),
- data, sizeof(data)) != sizeof(data))
- goto fail;
- qemu_free(s->refcount_table);
- old_table_offset = s->refcount_table_offset;
- old_table_size = s->refcount_table_size;
- s->refcount_table = new_table;
- s->refcount_table_size = new_table_size;
- s->refcount_table_offset = table_offset;
-
- update_refcount(bs, table_offset, new_table_size2, 1);
- free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
- return 0;
- fail:
- free_clusters(bs, table_offset, new_table_size2);
- qemu_free(new_table);
- return -EIO;
-}
-
-
-static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
-{
- BDRVQcowState *s = bs->opaque;
- int64_t offset, refcount_block_offset;
- int ret, refcount_table_index;
- uint64_t data64;
-
- /* Find L1 index and grow refcount table if needed */
- refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
- if (refcount_table_index >= s->refcount_table_size) {
- ret = grow_refcount_table(bs, refcount_table_index + 1);
- if (ret < 0)
- return ret;
- }
-
- /* Load or allocate the refcount block */
- refcount_block_offset = s->refcount_table[refcount_table_index];
- if (!refcount_block_offset) {
- /* create a new refcount block */
- /* Note: we cannot update the refcount now to avoid recursion */
- offset = alloc_clusters_noref(bs, s->cluster_size);
- memset(s->refcount_block_cache, 0, s->cluster_size);
- ret = bdrv_pwrite(s->hd, offset, s->refcount_block_cache, s->cluster_size);
- if (ret != s->cluster_size)
- return -EINVAL;
- s->refcount_table[refcount_table_index] = offset;
- data64 = cpu_to_be64(offset);
- ret = bdrv_pwrite(s->hd, s->refcount_table_offset +
- refcount_table_index * sizeof(uint64_t),
- &data64, sizeof(data64));
- if (ret != sizeof(data64))
- return -EINVAL;
-
- refcount_block_offset = offset;
- s->refcount_block_cache_offset = offset;
- update_refcount(bs, offset, s->cluster_size, 1);
- } else {
- if (refcount_block_offset != s->refcount_block_cache_offset) {
- if (load_refcount_block(bs, refcount_block_offset) < 0)
- return -EIO;
- }
- }
-
- return refcount_block_offset;
-}
-
-/* addend must be 1 or -1 */
-static int update_cluster_refcount(BlockDriverState *bs,
- int64_t cluster_index,
- int addend)
-{
- BDRVQcowState *s = bs->opaque;
- int ret;
-
- ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
- if (ret < 0) {
- return ret;
- }
-
- return get_refcount(bs, cluster_index);
-}
-
-/* XXX: cache several refcount block clusters ? */
-static int update_refcount(BlockDriverState *bs,
- int64_t offset, int64_t length,
- int addend)
-{
- BDRVQcowState *s = bs->opaque;
- int64_t start, last, cluster_offset;
- int64_t refcount_block_offset = 0;
- int64_t table_index = -1, old_table_index;
- int first_index = -1, last_index = -1;
-
-#ifdef DEBUG_ALLOC2
- printf("update_refcount: offset=%lld size=%lld addend=%d\n",
- offset, length, addend);
-#endif
- if (length <= 0)
- return -EINVAL;
- start = offset & ~(s->cluster_size - 1);
- last = (offset + length - 1) & ~(s->cluster_size - 1);
- for(cluster_offset = start; cluster_offset <= last;
- cluster_offset += s->cluster_size)
- {
- int block_index, refcount;
- int64_t cluster_index = cluster_offset >> s->cluster_bits;
-
- /* Only write refcount block to disk when we are done with it */
- old_table_index = table_index;
- table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
- if ((old_table_index >= 0) && (table_index != old_table_index)) {
- size_t size = (last_index - first_index + 1) << REFCOUNT_SHIFT;
- if (bdrv_pwrite(s->hd,
- refcount_block_offset + (first_index << REFCOUNT_SHIFT),
- &s->refcount_block_cache[first_index], size) != size)
- {
- return -EIO;
- }
-
- first_index = -1;
- last_index = -1;
- }
-
- /* Load the refcount block and allocate it if needed */
- refcount_block_offset = alloc_refcount_block(bs, cluster_index);
- if (refcount_block_offset < 0) {
- return refcount_block_offset;
- }
-
- /* we can update the count and save it */
- block_index = cluster_index &
- ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
- if (first_index == -1 || block_index < first_index) {
- first_index = block_index;
- }
- if (block_index > last_index) {
- last_index = block_index;
- }
-
- refcount = be16_to_cpu(s->refcount_block_cache[block_index]);
- refcount += addend;
- if (refcount < 0 || refcount > 0xffff)
- return -EINVAL;
- if (refcount == 0 && cluster_index < s->free_cluster_index) {
- s->free_cluster_index = cluster_index;
- }
- s->refcount_block_cache[block_index] = cpu_to_be16(refcount);
- }
-
- /* Write last changed block to disk */
- if (refcount_block_offset != 0) {
- size_t size = (last_index - first_index + 1) << REFCOUNT_SHIFT;
- if (bdrv_pwrite(s->hd,
- refcount_block_offset + (first_index << REFCOUNT_SHIFT),
- &s->refcount_block_cache[first_index], size) != size)
- {
- return -EIO;
- }
- }
-
- return 0;
-}
-
-/*
- * Increases the refcount for a range of clusters in a given refcount table.
- * This is used to construct a temporary refcount table out of L1 and L2 tables
- * which can be compared the the refcount table saved in the image.
- *
- * Returns the number of errors in the image that were found
- */
-static int inc_refcounts(BlockDriverState *bs,
- uint16_t *refcount_table,
- int refcount_table_size,
- int64_t offset, int64_t size)
-{
- BDRVQcowState *s = bs->opaque;
- int64_t start, last, cluster_offset;
- int k;
- int errors = 0;
-
- if (size <= 0)
- return 0;
-
- start = offset & ~(s->cluster_size - 1);
- last = (offset + size - 1) & ~(s->cluster_size - 1);
- for(cluster_offset = start; cluster_offset <= last;
- cluster_offset += s->cluster_size) {
- k = cluster_offset >> s->cluster_bits;
- if (k < 0 || k >= refcount_table_size) {
- fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n",
- cluster_offset);
- errors++;
- } else {
- if (++refcount_table[k] == 0) {
- fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
- "\n", cluster_offset);
- errors++;
- }
- }
- }
-
- return errors;
-}
-
-/*
- * Increases the refcount in the given refcount table for the all clusters
- * referenced in the L2 table. While doing so, performs some checks on L2
- * entries.
- *
- * Returns the number of errors found by the checks or -errno if an internal
- * error occurred.
- */
-static int check_refcounts_l2(BlockDriverState *bs,
- uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
- int check_copied)
-{
- BDRVQcowState *s = bs->opaque;
- uint64_t *l2_table, offset;
- int i, l2_size, nb_csectors, refcount;
- int errors = 0;
-
- /* Read L2 table from disk */
- l2_size = s->l2_size * sizeof(uint64_t);
- l2_table = qemu_malloc(l2_size);
-
- if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size)
- goto fail;
-
- /* Do the actual checks */
- for(i = 0; i < s->l2_size; i++) {
- offset = be64_to_cpu(l2_table[i]);
- if (offset != 0) {
- if (offset & QCOW_OFLAG_COMPRESSED) {
- /* Compressed clusters don't have QCOW_OFLAG_COPIED */
- if (offset & QCOW_OFLAG_COPIED) {
- fprintf(stderr, "ERROR: cluster %" PRId64 ": "
- "copied flag must never be set for compressed "
- "clusters\n", offset >> s->cluster_bits);
- offset &= ~QCOW_OFLAG_COPIED;
- errors++;
- }
-
- /* Mark cluster as used */
- nb_csectors = ((offset >> s->csize_shift) &
- s->csize_mask) + 1;
- offset &= s->cluster_offset_mask;
- errors += inc_refcounts(bs, refcount_table,
- refcount_table_size,
- offset & ~511, nb_csectors * 512);
- } else {
- /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
- if (check_copied) {
- uint64_t entry = offset;
- offset &= ~QCOW_OFLAG_COPIED;
- refcount = get_refcount(bs, offset >> s->cluster_bits);
- if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) {
- fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
- PRIx64 " refcount=%d\n", entry, refcount);
- errors++;
- }
- }
-
- /* Mark cluster as used */
- offset &= ~QCOW_OFLAG_COPIED;
- errors += inc_refcounts(bs, refcount_table,
- refcount_table_size,
- offset, s->cluster_size);
-
- /* Correct offsets are cluster aligned */
- if (offset & (s->cluster_size - 1)) {
- fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not "
- "properly aligned; L2 entry corrupted.\n", offset);
- errors++;
- }
- }
- }
- }
-
- qemu_free(l2_table);
- return errors;
-
-fail:
- fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
- qemu_free(l2_table);
- return -EIO;
-}
-
-/*
- * Increases the refcount for the L1 table, its L2 tables and all referenced
- * clusters in the given refcount table. While doing so, performs some checks
- * on L1 and L2 entries.
- *
- * Returns the number of errors found by the checks or -errno if an internal
- * error occurred.
- */
-static int check_refcounts_l1(BlockDriverState *bs,
- uint16_t *refcount_table,
- int refcount_table_size,
- int64_t l1_table_offset, int l1_size,
- int check_copied)
-{
- BDRVQcowState *s = bs->opaque;
- uint64_t *l1_table, l2_offset, l1_size2;
- int i, refcount, ret;
- int errors = 0;
-
- l1_size2 = l1_size * sizeof(uint64_t);
-
- /* Mark L1 table as used */
- errors += inc_refcounts(bs, refcount_table, refcount_table_size,
- l1_table_offset, l1_size2);
-
- /* Read L1 table entries from disk */
- l1_table = qemu_malloc(l1_size2);
- if (bdrv_pread(s->hd, l1_table_offset,
- l1_table, l1_size2) != l1_size2)
- goto fail;
- for(i = 0;i < l1_size; i++)
- be64_to_cpus(&l1_table[i]);
-
- /* Do the actual checks */
- for(i = 0; i < l1_size; i++) {
- l2_offset = l1_table[i];
- if (l2_offset) {
- /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
- if (check_copied) {
- refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED)
- >> s->cluster_bits);
- if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) {
- fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
- " refcount=%d\n", l2_offset, refcount);
- errors++;
- }
- }
-
- /* Mark L2 table as used */
- l2_offset &= ~QCOW_OFLAG_COPIED;
- errors += inc_refcounts(bs, refcount_table,
- refcount_table_size,
- l2_offset,
- s->cluster_size);
-
- /* L2 tables are cluster aligned */
- if (l2_offset & (s->cluster_size - 1)) {
- fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not "
- "cluster aligned; L1 entry corrupted\n", l2_offset);
- errors++;
- }
-
- /* Process and check L2 entries */
- ret = check_refcounts_l2(bs, refcount_table, refcount_table_size,
- l2_offset, check_copied);
- if (ret < 0) {
- goto fail;
- }
- errors += ret;
- }
- }
- qemu_free(l1_table);
- return errors;
-
-fail:
- fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
- qemu_free(l1_table);
- return -EIO;
-}
-
-/*
- * Checks an image for refcount consistency.
- *
- * Returns 0 if no errors are found, the number of errors in case the image is
- * detected as corrupted, and -errno when an internal error occured.
- */
-static int check_refcounts(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- int64_t size;
- int nb_clusters, refcount1, refcount2, i;
- QCowSnapshot *sn;
- uint16_t *refcount_table;
- int ret, errors = 0;
-
- size = bdrv_getlength(s->hd);
- nb_clusters = size_to_clusters(s, size);
- refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
-
- /* header */
- errors += inc_refcounts(bs, refcount_table, nb_clusters,
- 0, s->cluster_size);
-
- /* current L1 table */
- ret = check_refcounts_l1(bs, refcount_table, nb_clusters,
- s->l1_table_offset, s->l1_size, 1);
- if (ret < 0) {
- return ret;
- }
- errors += ret;
-
- /* snapshots */
- for(i = 0; i < s->nb_snapshots; i++) {
- sn = s->snapshots + i;
- check_refcounts_l1(bs, refcount_table, nb_clusters,
- sn->l1_table_offset, sn->l1_size, 0);
- }
- errors += inc_refcounts(bs, refcount_table, nb_clusters,
- s->snapshots_offset, s->snapshots_size);
-
- /* refcount data */
- errors += inc_refcounts(bs, refcount_table, nb_clusters,
- s->refcount_table_offset,
- s->refcount_table_size * sizeof(uint64_t));
- for(i = 0; i < s->refcount_table_size; i++) {
- int64_t offset;
- offset = s->refcount_table[i];
- if (offset != 0) {
- errors += inc_refcounts(bs, refcount_table, nb_clusters,
- offset, s->cluster_size);
- }
- }
-
- /* compare ref counts */
- for(i = 0; i < nb_clusters; i++) {
- refcount1 = get_refcount(bs, i);
- refcount2 = refcount_table[i];
- if (refcount1 != refcount2) {
- fprintf(stderr, "ERROR cluster %d refcount=%d reference=%d\n",
- i, refcount1, refcount2);
- errors++;
- }
- }
-
- qemu_free(refcount_table);
-
- return errors;
-}
-
static int qcow_check(BlockDriverState *bs)
{
return check_refcounts(bs);
diff --git a/block/qcow2.h b/block/qcow2.h
new file mode 100644
index 0000000..3a34212
--- /dev/null
+++ b/block/qcow2.h
@@ -0,0 +1,154 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef BLOCK_QCOW2_H
+#define BLOCK_QCOW2_H
+
+#include "aes.h"
+
+#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
+#define QCOW_VERSION 2
+
+#define QCOW_CRYPT_NONE 0
+#define QCOW_CRYPT_AES 1
+
+#define QCOW_MAX_CRYPT_CLUSTERS 32
+
+/* indicate that the refcount of the referenced cluster is exactly one. */
+#define QCOW_OFLAG_COPIED (1LL << 63)
+/* indicate that the cluster is compressed (they never have the copied flag) */
+#define QCOW_OFLAG_COMPRESSED (1LL << 62)
+
+#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */
+
+#define MIN_CLUSTER_BITS 9
+#define MAX_CLUSTER_BITS 16
+
+#define L2_CACHE_SIZE 16
+
+typedef struct QCowHeader {
+ uint32_t magic;
+ uint32_t version;
+ uint64_t backing_file_offset;
+ uint32_t backing_file_size;
+ uint32_t cluster_bits;
+ uint64_t size; /* in bytes */
+ uint32_t crypt_method;
+ uint32_t l1_size; /* XXX: save number of clusters instead ? */
+ uint64_t l1_table_offset;
+ uint64_t refcount_table_offset;
+ uint32_t refcount_table_clusters;
+ uint32_t nb_snapshots;
+ uint64_t snapshots_offset;
+} QCowHeader;
+
+typedef struct QCowSnapshot {
+ uint64_t l1_table_offset;
+ uint32_t l1_size;
+ char *id_str;
+ char *name;
+ uint32_t vm_state_size;
+ uint32_t date_sec;
+ uint32_t date_nsec;
+ uint64_t vm_clock_nsec;
+} QCowSnapshot;
+
+typedef struct BDRVQcowState {
+ BlockDriverState *hd;
+ int cluster_bits;
+ int cluster_size;
+ int cluster_sectors;
+ int l2_bits;
+ int l2_size;
+ int l1_size;
+ int l1_vm_state_index;
+ int csize_shift;
+ int csize_mask;
+ uint64_t cluster_offset_mask;
+ uint64_t l1_table_offset;
+ uint64_t *l1_table;
+ uint64_t *l2_cache;
+ uint64_t l2_cache_offsets[L2_CACHE_SIZE];
+ uint32_t l2_cache_counts[L2_CACHE_SIZE];
+ uint8_t *cluster_cache;
+ uint8_t *cluster_data;
+ uint64_t cluster_cache_offset;
+
+ uint64_t *refcount_table;
+ uint64_t refcount_table_offset;
+ uint32_t refcount_table_size;
+ uint64_t refcount_block_cache_offset;
+ uint16_t *refcount_block_cache;
+ int64_t free_cluster_index;
+ int64_t free_byte_offset;
+
+ uint32_t crypt_method; /* current crypt method, 0 if no key yet */
+ uint32_t crypt_method_header;
+ AES_KEY aes_encrypt_key;
+ AES_KEY aes_decrypt_key;
+ uint64_t snapshots_offset;
+ int snapshots_size;
+ int nb_snapshots;
+ QCowSnapshot *snapshots;
+} BDRVQcowState;
+
+/* XXX: use std qcow open function ? */
+typedef struct QCowCreateState {
+ int cluster_size;
+ int cluster_bits;
+ uint16_t *refcount_block;
+ uint64_t *refcount_table;
+ int64_t l1_table_offset;
+ int64_t refcount_table_offset;
+ int64_t refcount_block_offset;
+} QCowCreateState;
+
+static int size_to_clusters(BDRVQcowState *s, int64_t size)
+{
+ return (size + (s->cluster_size - 1)) >> s->cluster_bits;
+}
+
+// FIXME Need qcow2_ prefix to global functions
+
+/* qcow2.c functions */
+void l2_cache_reset(BlockDriverState *bs);
+
+/* qcow2-refcount.c functions */
+int refcount_init(BlockDriverState *bs);
+void refcount_close(BlockDriverState *bs);
+
+int64_t alloc_clusters(BlockDriverState *bs, int64_t size);
+int64_t alloc_bytes(BlockDriverState *bs, int size);
+void free_clusters(BlockDriverState *bs,
+ int64_t offset, int64_t size);
+
+void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size);
+int update_snapshot_refcount(BlockDriverState *bs,
+ int64_t l1_table_offset,
+ int l1_size,
+ int addend);
+
+int check_refcounts(BlockDriverState *bs);
+
+#endif
--
1.6.0.6
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH 2/4] qcow2: Split out guest cluster functions
2009-05-28 14:07 [Qemu-devel] [PATCH 0/4] Split qcow2 driver Kevin Wolf
2009-05-28 14:07 ` [Qemu-devel] [PATCH 1/4] qcow2: Split out refcount handling Kevin Wolf
@ 2009-05-28 14:07 ` Kevin Wolf
2009-05-28 14:07 ` [Qemu-devel] [PATCH 3/4] qcow2: Split out snapshot functions Kevin Wolf
` (2 subsequent siblings)
4 siblings, 0 replies; 9+ messages in thread
From: Kevin Wolf @ 2009-05-28 14:07 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf
qcow2-cluster.c contains all functions related to the management of guest
clusters, i.e. what the guest sees on its virtual disk. This code is about
mapping these guest clusters to host clusters in the image file using the
two-level lookup tables.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
Makefile | 2 +-
block/qcow2-cluster.c | 754 +++++++++++++++++++++++++++++++++++++++++++++++
block/qcow2-refcount.c | 28 ++
block/qcow2.c | 767 +-----------------------------------------------
block/qcow2.h | 37 +++-
5 files changed, 820 insertions(+), 768 deletions(-)
create mode 100644 block/qcow2-cluster.c
diff --git a/Makefile b/Makefile
index 5a0fdbe..7bc37ce 100644
--- a/Makefile
+++ b/Makefile
@@ -68,7 +68,7 @@ recurse-all: $(SUBDIR_RULES)
BLOCK_OBJS=cutils.o cache-utils.o qemu-malloc.o qemu-option.o module.o
BLOCK_OBJS+=block/cow.o block/qcow.o aes.o block/vmdk.o block/cloop.o
BLOCK_OBJS+=block/dmg.o block/bochs.o block/vpc.o block/vvfat.o
-BLOCK_OBJS+=block/qcow2.o block/qcow2-refcount.o
+BLOCK_OBJS+=block/qcow2.o block/qcow2-refcount.o block/qcow2-cluster.o
BLOCK_OBJS+=block/parallels.o block/nbd.o
BLOCK_OBJS+=nbd.o block.o aio.o
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
new file mode 100644
index 0000000..494cc91
--- /dev/null
+++ b/block/qcow2-cluster.c
@@ -0,0 +1,754 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <zlib.h>
+
+#include "qemu-common.h"
+#include "block_int.h"
+#include "block/qcow2.h"
+
+int grow_l1_table(BlockDriverState *bs, int min_size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int new_l1_size, new_l1_size2, ret, i;
+ uint64_t *new_l1_table;
+ uint64_t new_l1_table_offset;
+ uint8_t data[12];
+
+ new_l1_size = s->l1_size;
+ if (min_size <= new_l1_size)
+ return 0;
+ while (min_size > new_l1_size) {
+ new_l1_size = (new_l1_size * 3 + 1) / 2;
+ }
+#ifdef DEBUG_ALLOC2
+ printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size);
+#endif
+
+ new_l1_size2 = sizeof(uint64_t) * new_l1_size;
+ new_l1_table = qemu_mallocz(new_l1_size2);
+ memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
+
+ /* write new table (align to cluster) */
+ new_l1_table_offset = alloc_clusters(bs, new_l1_size2);
+
+ for(i = 0; i < s->l1_size; i++)
+ new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
+ ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2);
+ if (ret != new_l1_size2)
+ goto fail;
+ for(i = 0; i < s->l1_size; i++)
+ new_l1_table[i] = be64_to_cpu(new_l1_table[i]);
+
+ /* set new table */
+ cpu_to_be32w((uint32_t*)data, new_l1_size);
+ cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset);
+ if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data,
+ sizeof(data)) != sizeof(data))
+ goto fail;
+ qemu_free(s->l1_table);
+ free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
+ s->l1_table_offset = new_l1_table_offset;
+ s->l1_table = new_l1_table;
+ s->l1_size = new_l1_size;
+ return 0;
+ fail:
+ qemu_free(s->l1_table);
+ return -EIO;
+}
+
+void l2_cache_reset(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+
+ memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
+ memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
+ memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
+}
+
+static inline int l2_cache_new_entry(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint32_t min_count;
+ int min_index, i;
+
+ /* find a new entry in the least used one */
+ min_index = 0;
+ min_count = 0xffffffff;
+ for(i = 0; i < L2_CACHE_SIZE; i++) {
+ if (s->l2_cache_counts[i] < min_count) {
+ min_count = s->l2_cache_counts[i];
+ min_index = i;
+ }
+ }
+ return min_index;
+}
+
+/*
+ * seek_l2_table
+ *
+ * seek l2_offset in the l2_cache table
+ * if not found, return NULL,
+ * if found,
+ * increments the l2 cache hit count of the entry,
+ * if counter overflow, divide by two all counters
+ * return the pointer to the l2 cache entry
+ *
+ */
+
+static uint64_t *seek_l2_table(BDRVQcowState *s, uint64_t l2_offset)
+{
+ int i, j;
+
+ for(i = 0; i < L2_CACHE_SIZE; i++) {
+ if (l2_offset == s->l2_cache_offsets[i]) {
+ /* increment the hit count */
+ if (++s->l2_cache_counts[i] == 0xffffffff) {
+ for(j = 0; j < L2_CACHE_SIZE; j++) {
+ s->l2_cache_counts[j] >>= 1;
+ }
+ }
+ return s->l2_cache + (i << s->l2_bits);
+ }
+ }
+ return NULL;
+}
+
+/*
+ * l2_load
+ *
+ * Loads a L2 table into memory. If the table is in the cache, the cache
+ * is used; otherwise the L2 table is loaded from the image file.
+ *
+ * Returns a pointer to the L2 table on success, or NULL if the read from
+ * the image file failed.
+ */
+
+static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset)
+{
+ BDRVQcowState *s = bs->opaque;
+ int min_index;
+ uint64_t *l2_table;
+
+ /* seek if the table for the given offset is in the cache */
+
+ l2_table = seek_l2_table(s, l2_offset);
+ if (l2_table != NULL)
+ return l2_table;
+
+ /* not found: load a new entry in the least used one */
+
+ min_index = l2_cache_new_entry(bs);
+ l2_table = s->l2_cache + (min_index << s->l2_bits);
+ if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
+ s->l2_size * sizeof(uint64_t))
+ return NULL;
+ s->l2_cache_offsets[min_index] = l2_offset;
+ s->l2_cache_counts[min_index] = 1;
+
+ return l2_table;
+}
+
+/*
+ * l2_allocate
+ *
+ * Allocate a new l2 entry in the file. If l1_index points to an already
+ * used entry in the L2 table (i.e. we are doing a copy on write for the L2
+ * table) copy the contents of the old L2 table into the newly allocated one.
+ * Otherwise the new table is initialized with zeros.
+ *
+ */
+
+static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index)
+{
+ BDRVQcowState *s = bs->opaque;
+ int min_index;
+ uint64_t old_l2_offset, tmp;
+ uint64_t *l2_table, l2_offset;
+
+ old_l2_offset = s->l1_table[l1_index];
+
+ /* allocate a new l2 entry */
+
+ l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
+
+ /* update the L1 entry */
+
+ s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED;
+
+ tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED);
+ if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp),
+ &tmp, sizeof(tmp)) != sizeof(tmp))
+ return NULL;
+
+ /* allocate a new entry in the l2 cache */
+
+ min_index = l2_cache_new_entry(bs);
+ l2_table = s->l2_cache + (min_index << s->l2_bits);
+
+ if (old_l2_offset == 0) {
+ /* if there was no old l2 table, clear the new table */
+ memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
+ } else {
+ /* if there was an old l2 table, read it from the disk */
+ if (bdrv_pread(s->hd, old_l2_offset,
+ l2_table, s->l2_size * sizeof(uint64_t)) !=
+ s->l2_size * sizeof(uint64_t))
+ return NULL;
+ }
+ /* write the l2 table to the file */
+ if (bdrv_pwrite(s->hd, l2_offset,
+ l2_table, s->l2_size * sizeof(uint64_t)) !=
+ s->l2_size * sizeof(uint64_t))
+ return NULL;
+
+ /* update the l2 cache entry */
+
+ s->l2_cache_offsets[min_index] = l2_offset;
+ s->l2_cache_counts[min_index] = 1;
+
+ return l2_table;
+}
+
+static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size,
+ uint64_t *l2_table, uint64_t start, uint64_t mask)
+{
+ int i;
+ uint64_t offset = be64_to_cpu(l2_table[0]) & ~mask;
+
+ if (!offset)
+ return 0;
+
+ for (i = start; i < start + nb_clusters; i++)
+ if (offset + i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask))
+ break;
+
+ return (i - start);
+}
+
+static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table)
+{
+ int i = 0;
+
+ while(nb_clusters-- && l2_table[i] == 0)
+ i++;
+
+ return i;
+}
+
+/* The crypt function is compatible with the linux cryptoloop
+ algorithm for < 4 GB images. NOTE: out_buf == in_buf is
+ supported */
+void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+ uint8_t *out_buf, const uint8_t *in_buf,
+ int nb_sectors, int enc,
+ const AES_KEY *key)
+{
+ union {
+ uint64_t ll[2];
+ uint8_t b[16];
+ } ivec;
+ int i;
+
+ for(i = 0; i < nb_sectors; i++) {
+ ivec.ll[0] = cpu_to_le64(sector_num);
+ ivec.ll[1] = 0;
+ AES_cbc_encrypt(in_buf, out_buf, 512, key,
+ ivec.b, enc);
+ sector_num++;
+ in_buf += 512;
+ out_buf += 512;
+ }
+}
+
+
+static int qcow_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ BDRVQcowState *s = bs->opaque;
+ int ret, index_in_cluster, n, n1;
+ uint64_t cluster_offset;
+
+ while (nb_sectors > 0) {
+ n = nb_sectors;
+ cluster_offset = get_cluster_offset(bs, sector_num << 9, &n);
+ index_in_cluster = sector_num & (s->cluster_sectors - 1);
+ if (!cluster_offset) {
+ if (bs->backing_hd) {
+ /* read from the base image */
+ n1 = backing_read1(bs->backing_hd, sector_num, buf, n);
+ if (n1 > 0) {
+ ret = bdrv_read(bs->backing_hd, sector_num, buf, n1);
+ if (ret < 0)
+ return -1;
+ }
+ } else {
+ memset(buf, 0, 512 * n);
+ }
+ } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
+ if (decompress_cluster(s, cluster_offset) < 0)
+ return -1;
+ memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);
+ } else {
+ ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);
+ if (ret != n * 512)
+ return -1;
+ if (s->crypt_method) {
+ encrypt_sectors(s, sector_num, buf, buf, n, 0,
+ &s->aes_decrypt_key);
+ }
+ }
+ nb_sectors -= n;
+ sector_num += n;
+ buf += n * 512;
+ }
+ return 0;
+}
+
+static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
+ uint64_t cluster_offset, int n_start, int n_end)
+{
+ BDRVQcowState *s = bs->opaque;
+ int n, ret;
+
+ n = n_end - n_start;
+ if (n <= 0)
+ return 0;
+ ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n);
+ if (ret < 0)
+ return ret;
+ if (s->crypt_method) {
+ encrypt_sectors(s, start_sect + n_start,
+ s->cluster_data,
+ s->cluster_data, n, 1,
+ &s->aes_encrypt_key);
+ }
+ ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start,
+ s->cluster_data, n);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+
+/*
+ * get_cluster_offset
+ *
+ * For a given offset of the disk image, return cluster offset in
+ * qcow2 file.
+ *
+ * on entry, *num is the number of contiguous clusters we'd like to
+ * access following offset.
+ *
+ * on exit, *num is the number of contiguous clusters we can read.
+ *
+ * Return 1, if the offset is found
+ * Return 0, otherwise.
+ *
+ */
+
+uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int *num)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l1_index, l2_index;
+ uint64_t l2_offset, *l2_table, cluster_offset;
+ int l1_bits, c;
+ int index_in_cluster, nb_available, nb_needed, nb_clusters;
+
+ index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1);
+ nb_needed = *num + index_in_cluster;
+
+ l1_bits = s->l2_bits + s->cluster_bits;
+
+ /* compute how many bytes there are between the offset and
+ * the end of the l1 entry
+ */
+
+ nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1));
+
+ /* compute the number of available sectors */
+
+ nb_available = (nb_available >> 9) + index_in_cluster;
+
+ if (nb_needed > nb_available) {
+ nb_needed = nb_available;
+ }
+
+ cluster_offset = 0;
+
+ /* seek the the l2 offset in the l1 table */
+
+ l1_index = offset >> l1_bits;
+ if (l1_index >= s->l1_size)
+ goto out;
+
+ l2_offset = s->l1_table[l1_index];
+
+ /* seek the l2 table of the given l2 offset */
+
+ if (!l2_offset)
+ goto out;
+
+ /* load the l2 table in memory */
+
+ l2_offset &= ~QCOW_OFLAG_COPIED;
+ l2_table = l2_load(bs, l2_offset);
+ if (l2_table == NULL)
+ return 0;
+
+ /* find the cluster offset for the given disk offset */
+
+ l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
+ cluster_offset = be64_to_cpu(l2_table[l2_index]);
+ nb_clusters = size_to_clusters(s, nb_needed << 9);
+
+ if (!cluster_offset) {
+ /* how many empty clusters ? */
+ c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]);
+ } else {
+ /* how many allocated clusters ? */
+ c = count_contiguous_clusters(nb_clusters, s->cluster_size,
+ &l2_table[l2_index], 0, QCOW_OFLAG_COPIED);
+ }
+
+ nb_available = (c * s->cluster_sectors);
+out:
+ if (nb_available > nb_needed)
+ nb_available = nb_needed;
+
+ *num = nb_available - index_in_cluster;
+
+ return cluster_offset & ~QCOW_OFLAG_COPIED;
+}
+
+/*
+ * get_cluster_table
+ *
+ * for a given disk offset, load (and allocate if needed)
+ * the l2 table.
+ *
+ * the l2 table offset in the qcow2 file and the cluster index
+ * in the l2 table are given to the caller.
+ *
+ */
+
+static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
+ uint64_t **new_l2_table,
+ uint64_t *new_l2_offset,
+ int *new_l2_index)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l1_index, l2_index, ret;
+ uint64_t l2_offset, *l2_table;
+
+ /* seek the the l2 offset in the l1 table */
+
+ l1_index = offset >> (s->l2_bits + s->cluster_bits);
+ if (l1_index >= s->l1_size) {
+ ret = grow_l1_table(bs, l1_index + 1);
+ if (ret < 0)
+ return 0;
+ }
+ l2_offset = s->l1_table[l1_index];
+
+ /* seek the l2 table of the given l2 offset */
+
+ if (l2_offset & QCOW_OFLAG_COPIED) {
+ /* load the l2 table in memory */
+ l2_offset &= ~QCOW_OFLAG_COPIED;
+ l2_table = l2_load(bs, l2_offset);
+ if (l2_table == NULL)
+ return 0;
+ } else {
+ if (l2_offset)
+ free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
+ l2_table = l2_allocate(bs, l1_index);
+ if (l2_table == NULL)
+ return 0;
+ l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED;
+ }
+
+ /* find the cluster offset for the given disk offset */
+
+ l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
+
+ *new_l2_table = l2_table;
+ *new_l2_offset = l2_offset;
+ *new_l2_index = l2_index;
+
+ return 1;
+}
+
+/*
+ * alloc_compressed_cluster_offset
+ *
+ * For a given offset of the disk image, return cluster offset in
+ * qcow2 file.
+ *
+ * If the offset is not found, allocate a new compressed cluster.
+ *
+ * Return the cluster offset if successful,
+ * Return 0, otherwise.
+ *
+ */
+
+uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int compressed_size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l2_index, ret;
+ uint64_t l2_offset, *l2_table, cluster_offset;
+ int nb_csectors;
+
+ ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
+ if (ret == 0)
+ return 0;
+
+ cluster_offset = be64_to_cpu(l2_table[l2_index]);
+ if (cluster_offset & QCOW_OFLAG_COPIED)
+ return cluster_offset & ~QCOW_OFLAG_COPIED;
+
+ if (cluster_offset)
+ free_any_clusters(bs, cluster_offset, 1);
+
+ cluster_offset = alloc_bytes(bs, compressed_size);
+ nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
+ (cluster_offset >> 9);
+
+ cluster_offset |= QCOW_OFLAG_COMPRESSED |
+ ((uint64_t)nb_csectors << s->csize_shift);
+
+ /* update L2 table */
+
+ /* compressed clusters never have the copied flag */
+
+ l2_table[l2_index] = cpu_to_be64(cluster_offset);
+ if (bdrv_pwrite(s->hd,
+ l2_offset + l2_index * sizeof(uint64_t),
+ l2_table + l2_index,
+ sizeof(uint64_t)) != sizeof(uint64_t))
+ return 0;
+
+ return cluster_offset;
+}
+
+int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
+ QCowL2Meta *m)
+{
+ BDRVQcowState *s = bs->opaque;
+ int i, j = 0, l2_index, ret;
+ uint64_t *old_cluster, start_sect, l2_offset, *l2_table;
+
+ if (m->nb_clusters == 0)
+ return 0;
+
+ old_cluster = qemu_malloc(m->nb_clusters * sizeof(uint64_t));
+
+ /* copy content of unmodified sectors */
+ start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9;
+ if (m->n_start) {
+ ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start);
+ if (ret < 0)
+ goto err;
+ }
+
+ if (m->nb_available & (s->cluster_sectors - 1)) {
+ uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1);
+ ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9),
+ m->nb_available - end, s->cluster_sectors);
+ if (ret < 0)
+ goto err;
+ }
+
+ ret = -EIO;
+ /* update L2 table */
+ if (!get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index))
+ goto err;
+
+ for (i = 0; i < m->nb_clusters; i++) {
+ /* if two concurrent writes happen to the same unallocated cluster
+ * each write allocates separate cluster and writes data concurrently.
+ * The first one to complete updates l2 table with pointer to its
+ * cluster the second one has to do RMW (which is done above by
+ * copy_sectors()), update l2 table with its cluster pointer and free
+ * old cluster. This is what this loop does */
+ if(l2_table[l2_index + i] != 0)
+ old_cluster[j++] = l2_table[l2_index + i];
+
+ l2_table[l2_index + i] = cpu_to_be64((cluster_offset +
+ (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);
+ }
+
+ if (bdrv_pwrite(s->hd, l2_offset + l2_index * sizeof(uint64_t),
+ l2_table + l2_index, m->nb_clusters * sizeof(uint64_t)) !=
+ m->nb_clusters * sizeof(uint64_t))
+ goto err;
+
+ for (i = 0; i < j; i++)
+ free_any_clusters(bs, be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED,
+ 1);
+
+ ret = 0;
+err:
+ qemu_free(old_cluster);
+ return ret;
+ }
+
+/*
+ * alloc_cluster_offset
+ *
+ * For a given offset of the disk image, return cluster offset in
+ * qcow2 file.
+ *
+ * If the offset is not found, allocate a new cluster.
+ *
+ * Return the cluster offset if successful,
+ * Return 0, otherwise.
+ *
+ */
+
+uint64_t alloc_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int n_start, int n_end,
+ int *num, QCowL2Meta *m)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l2_index, ret;
+ uint64_t l2_offset, *l2_table, cluster_offset;
+ int nb_clusters, i = 0;
+
+ ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
+ if (ret == 0)
+ return 0;
+
+ nb_clusters = size_to_clusters(s, n_end << 9);
+
+ nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+
+ cluster_offset = be64_to_cpu(l2_table[l2_index]);
+
+ /* We keep all QCOW_OFLAG_COPIED clusters */
+
+ if (cluster_offset & QCOW_OFLAG_COPIED) {
+ nb_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size,
+ &l2_table[l2_index], 0, 0);
+
+ cluster_offset &= ~QCOW_OFLAG_COPIED;
+ m->nb_clusters = 0;
+
+ goto out;
+ }
+
+ /* for the moment, multiple compressed clusters are not managed */
+
+ if (cluster_offset & QCOW_OFLAG_COMPRESSED)
+ nb_clusters = 1;
+
+ /* how many available clusters ? */
+
+ while (i < nb_clusters) {
+ i += count_contiguous_clusters(nb_clusters - i, s->cluster_size,
+ &l2_table[l2_index], i, 0);
+
+ if(be64_to_cpu(l2_table[l2_index + i]))
+ break;
+
+ i += count_contiguous_free_clusters(nb_clusters - i,
+ &l2_table[l2_index + i]);
+
+ cluster_offset = be64_to_cpu(l2_table[l2_index + i]);
+
+ if ((cluster_offset & QCOW_OFLAG_COPIED) ||
+ (cluster_offset & QCOW_OFLAG_COMPRESSED))
+ break;
+ }
+ nb_clusters = i;
+
+ /* allocate a new cluster */
+
+ cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size);
+
+ /* save info needed for meta data update */
+ m->offset = offset;
+ m->n_start = n_start;
+ m->nb_clusters = nb_clusters;
+
+out:
+ m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end);
+
+ *num = m->nb_available - n_start;
+
+ return cluster_offset;
+}
+
+static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
+ const uint8_t *buf, int buf_size)
+{
+ z_stream strm1, *strm = &strm1;
+ int ret, out_len;
+
+ memset(strm, 0, sizeof(*strm));
+
+ strm->next_in = (uint8_t *)buf;
+ strm->avail_in = buf_size;
+ strm->next_out = out_buf;
+ strm->avail_out = out_buf_size;
+
+ ret = inflateInit2(strm, -12);
+ if (ret != Z_OK)
+ return -1;
+ ret = inflate(strm, Z_FINISH);
+ out_len = strm->next_out - out_buf;
+ if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
+ out_len != out_buf_size) {
+ inflateEnd(strm);
+ return -1;
+ }
+ inflateEnd(strm);
+ return 0;
+}
+
+int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
+{
+ int ret, csize, nb_csectors, sector_offset;
+ uint64_t coffset;
+
+ coffset = cluster_offset & s->cluster_offset_mask;
+ if (s->cluster_cache_offset != coffset) {
+ nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
+ sector_offset = coffset & 511;
+ csize = nb_csectors * 512 - sector_offset;
+ ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors);
+ if (ret < 0) {
+ return -1;
+ }
+ if (decompress_buffer(s->cluster_cache, s->cluster_size,
+ s->cluster_data + sector_offset, csize) < 0) {
+ return -1;
+ }
+ s->cluster_cache_offset = coffset;
+ }
+ return 0;
+}
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index b70afe9..3f461c6 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -389,6 +389,34 @@ void free_clusters(BlockDriverState *bs,
update_refcount(bs, offset, size, -1);
}
+/*
+ * free_any_clusters
+ *
+ * free clusters according to its type: compressed or not
+ *
+ */
+
+void free_any_clusters(BlockDriverState *bs,
+ uint64_t cluster_offset, int nb_clusters)
+{
+ BDRVQcowState *s = bs->opaque;
+
+ /* free the cluster */
+
+ if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
+ int nb_csectors;
+ nb_csectors = ((cluster_offset >> s->csize_shift) &
+ s->csize_mask) + 1;
+ free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511,
+ nb_csectors * 512);
+ return;
+ }
+
+ free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits);
+
+ return;
+}
+
/*********************************************************/
diff --git a/block/qcow2.c b/block/qcow2.c
index f9ff44f..a91aaeb 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -78,9 +78,6 @@ typedef struct __attribute__((packed)) QCowSnapshotHeader {
} QCowSnapshotHeader;
-static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
-static int qcow_read(BlockDriverState *bs, int64_t sector_num,
- uint8_t *buf, int nb_sectors);
static int qcow_read_snapshots(BlockDriverState *bs);
static void qcow_free_snapshots(BlockDriverState *bs);
@@ -334,679 +331,12 @@ static int qcow_set_key(BlockDriverState *bs, const char *key)
return 0;
}
-/* The crypt function is compatible with the linux cryptoloop
- algorithm for < 4 GB images. NOTE: out_buf == in_buf is
- supported */
-static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
- uint8_t *out_buf, const uint8_t *in_buf,
- int nb_sectors, int enc,
- const AES_KEY *key)
-{
- union {
- uint64_t ll[2];
- uint8_t b[16];
- } ivec;
- int i;
-
- for(i = 0; i < nb_sectors; i++) {
- ivec.ll[0] = cpu_to_le64(sector_num);
- ivec.ll[1] = 0;
- AES_cbc_encrypt(in_buf, out_buf, 512, key,
- ivec.b, enc);
- sector_num++;
- in_buf += 512;
- out_buf += 512;
- }
-}
-
-static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
- uint64_t cluster_offset, int n_start, int n_end)
-{
- BDRVQcowState *s = bs->opaque;
- int n, ret;
-
- n = n_end - n_start;
- if (n <= 0)
- return 0;
- ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n);
- if (ret < 0)
- return ret;
- if (s->crypt_method) {
- encrypt_sectors(s, start_sect + n_start,
- s->cluster_data,
- s->cluster_data, n, 1,
- &s->aes_encrypt_key);
- }
- ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start,
- s->cluster_data, n);
- if (ret < 0)
- return ret;
- return 0;
-}
-
-void l2_cache_reset(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
-
- memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
- memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
- memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
-}
-
-static inline int l2_cache_new_entry(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- uint32_t min_count;
- int min_index, i;
-
- /* find a new entry in the least used one */
- min_index = 0;
- min_count = 0xffffffff;
- for(i = 0; i < L2_CACHE_SIZE; i++) {
- if (s->l2_cache_counts[i] < min_count) {
- min_count = s->l2_cache_counts[i];
- min_index = i;
- }
- }
- return min_index;
-}
-
static int64_t align_offset(int64_t offset, int n)
{
offset = (offset + n - 1) & ~(n - 1);
return offset;
}
-static int grow_l1_table(BlockDriverState *bs, int min_size)
-{
- BDRVQcowState *s = bs->opaque;
- int new_l1_size, new_l1_size2, ret, i;
- uint64_t *new_l1_table;
- uint64_t new_l1_table_offset;
- uint8_t data[12];
-
- new_l1_size = s->l1_size;
- if (min_size <= new_l1_size)
- return 0;
- while (min_size > new_l1_size) {
- new_l1_size = (new_l1_size * 3 + 1) / 2;
- }
-#ifdef DEBUG_ALLOC2
- printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size);
-#endif
-
- new_l1_size2 = sizeof(uint64_t) * new_l1_size;
- new_l1_table = qemu_mallocz(new_l1_size2);
- memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
-
- /* write new table (align to cluster) */
- new_l1_table_offset = alloc_clusters(bs, new_l1_size2);
-
- for(i = 0; i < s->l1_size; i++)
- new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
- ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2);
- if (ret != new_l1_size2)
- goto fail;
- for(i = 0; i < s->l1_size; i++)
- new_l1_table[i] = be64_to_cpu(new_l1_table[i]);
-
- /* set new table */
- cpu_to_be32w((uint32_t*)data, new_l1_size);
- cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset);
- if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data,
- sizeof(data)) != sizeof(data))
- goto fail;
- qemu_free(s->l1_table);
- free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
- s->l1_table_offset = new_l1_table_offset;
- s->l1_table = new_l1_table;
- s->l1_size = new_l1_size;
- return 0;
- fail:
- qemu_free(s->l1_table);
- return -EIO;
-}
-
-/*
- * seek_l2_table
- *
- * seek l2_offset in the l2_cache table
- * if not found, return NULL,
- * if found,
- * increments the l2 cache hit count of the entry,
- * if counter overflow, divide by two all counters
- * return the pointer to the l2 cache entry
- *
- */
-
-static uint64_t *seek_l2_table(BDRVQcowState *s, uint64_t l2_offset)
-{
- int i, j;
-
- for(i = 0; i < L2_CACHE_SIZE; i++) {
- if (l2_offset == s->l2_cache_offsets[i]) {
- /* increment the hit count */
- if (++s->l2_cache_counts[i] == 0xffffffff) {
- for(j = 0; j < L2_CACHE_SIZE; j++) {
- s->l2_cache_counts[j] >>= 1;
- }
- }
- return s->l2_cache + (i << s->l2_bits);
- }
- }
- return NULL;
-}
-
-/*
- * l2_load
- *
- * Loads a L2 table into memory. If the table is in the cache, the cache
- * is used; otherwise the L2 table is loaded from the image file.
- *
- * Returns a pointer to the L2 table on success, or NULL if the read from
- * the image file failed.
- */
-
-static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset)
-{
- BDRVQcowState *s = bs->opaque;
- int min_index;
- uint64_t *l2_table;
-
- /* seek if the table for the given offset is in the cache */
-
- l2_table = seek_l2_table(s, l2_offset);
- if (l2_table != NULL)
- return l2_table;
-
- /* not found: load a new entry in the least used one */
-
- min_index = l2_cache_new_entry(bs);
- l2_table = s->l2_cache + (min_index << s->l2_bits);
- if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
- s->l2_size * sizeof(uint64_t))
- return NULL;
- s->l2_cache_offsets[min_index] = l2_offset;
- s->l2_cache_counts[min_index] = 1;
-
- return l2_table;
-}
-
-/*
- * l2_allocate
- *
- * Allocate a new l2 entry in the file. If l1_index points to an already
- * used entry in the L2 table (i.e. we are doing a copy on write for the L2
- * table) copy the contents of the old L2 table into the newly allocated one.
- * Otherwise the new table is initialized with zeros.
- *
- */
-
-static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index)
-{
- BDRVQcowState *s = bs->opaque;
- int min_index;
- uint64_t old_l2_offset, tmp;
- uint64_t *l2_table, l2_offset;
-
- old_l2_offset = s->l1_table[l1_index];
-
- /* allocate a new l2 entry */
-
- l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
-
- /* update the L1 entry */
-
- s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED;
-
- tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED);
- if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp),
- &tmp, sizeof(tmp)) != sizeof(tmp))
- return NULL;
-
- /* allocate a new entry in the l2 cache */
-
- min_index = l2_cache_new_entry(bs);
- l2_table = s->l2_cache + (min_index << s->l2_bits);
-
- if (old_l2_offset == 0) {
- /* if there was no old l2 table, clear the new table */
- memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
- } else {
- /* if there was an old l2 table, read it from the disk */
- if (bdrv_pread(s->hd, old_l2_offset,
- l2_table, s->l2_size * sizeof(uint64_t)) !=
- s->l2_size * sizeof(uint64_t))
- return NULL;
- }
- /* write the l2 table to the file */
- if (bdrv_pwrite(s->hd, l2_offset,
- l2_table, s->l2_size * sizeof(uint64_t)) !=
- s->l2_size * sizeof(uint64_t))
- return NULL;
-
- /* update the l2 cache entry */
-
- s->l2_cache_offsets[min_index] = l2_offset;
- s->l2_cache_counts[min_index] = 1;
-
- return l2_table;
-}
-
-static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size,
- uint64_t *l2_table, uint64_t start, uint64_t mask)
-{
- int i;
- uint64_t offset = be64_to_cpu(l2_table[0]) & ~mask;
-
- if (!offset)
- return 0;
-
- for (i = start; i < start + nb_clusters; i++)
- if (offset + i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask))
- break;
-
- return (i - start);
-}
-
-static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table)
-{
- int i = 0;
-
- while(nb_clusters-- && l2_table[i] == 0)
- i++;
-
- return i;
-}
-
-/*
- * get_cluster_offset
- *
- * For a given offset of the disk image, return cluster offset in
- * qcow2 file.
- *
- * on entry, *num is the number of contiguous clusters we'd like to
- * access following offset.
- *
- * on exit, *num is the number of contiguous clusters we can read.
- *
- * Return 1, if the offset is found
- * Return 0, otherwise.
- *
- */
-
-static uint64_t get_cluster_offset(BlockDriverState *bs,
- uint64_t offset, int *num)
-{
- BDRVQcowState *s = bs->opaque;
- int l1_index, l2_index;
- uint64_t l2_offset, *l2_table, cluster_offset;
- int l1_bits, c;
- int index_in_cluster, nb_available, nb_needed, nb_clusters;
-
- index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1);
- nb_needed = *num + index_in_cluster;
-
- l1_bits = s->l2_bits + s->cluster_bits;
-
- /* compute how many bytes there are between the offset and
- * the end of the l1 entry
- */
-
- nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1));
-
- /* compute the number of available sectors */
-
- nb_available = (nb_available >> 9) + index_in_cluster;
-
- if (nb_needed > nb_available) {
- nb_needed = nb_available;
- }
-
- cluster_offset = 0;
-
- /* seek the the l2 offset in the l1 table */
-
- l1_index = offset >> l1_bits;
- if (l1_index >= s->l1_size)
- goto out;
-
- l2_offset = s->l1_table[l1_index];
-
- /* seek the l2 table of the given l2 offset */
-
- if (!l2_offset)
- goto out;
-
- /* load the l2 table in memory */
-
- l2_offset &= ~QCOW_OFLAG_COPIED;
- l2_table = l2_load(bs, l2_offset);
- if (l2_table == NULL)
- return 0;
-
- /* find the cluster offset for the given disk offset */
-
- l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
- cluster_offset = be64_to_cpu(l2_table[l2_index]);
- nb_clusters = size_to_clusters(s, nb_needed << 9);
-
- if (!cluster_offset) {
- /* how many empty clusters ? */
- c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]);
- } else {
- /* how many allocated clusters ? */
- c = count_contiguous_clusters(nb_clusters, s->cluster_size,
- &l2_table[l2_index], 0, QCOW_OFLAG_COPIED);
- }
-
- nb_available = (c * s->cluster_sectors);
-out:
- if (nb_available > nb_needed)
- nb_available = nb_needed;
-
- *num = nb_available - index_in_cluster;
-
- return cluster_offset & ~QCOW_OFLAG_COPIED;
-}
-
-/*
- * free_any_clusters
- *
- * free clusters according to its type: compressed or not
- *
- */
-
-static void free_any_clusters(BlockDriverState *bs,
- uint64_t cluster_offset, int nb_clusters)
-{
- BDRVQcowState *s = bs->opaque;
-
- /* free the cluster */
-
- if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
- int nb_csectors;
- nb_csectors = ((cluster_offset >> s->csize_shift) &
- s->csize_mask) + 1;
- free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511,
- nb_csectors * 512);
- return;
- }
-
- free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits);
-
- return;
-}
-
-/*
- * get_cluster_table
- *
- * for a given disk offset, load (and allocate if needed)
- * the l2 table.
- *
- * the l2 table offset in the qcow2 file and the cluster index
- * in the l2 table are given to the caller.
- *
- */
-
-static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
- uint64_t **new_l2_table,
- uint64_t *new_l2_offset,
- int *new_l2_index)
-{
- BDRVQcowState *s = bs->opaque;
- int l1_index, l2_index, ret;
- uint64_t l2_offset, *l2_table;
-
- /* seek the the l2 offset in the l1 table */
-
- l1_index = offset >> (s->l2_bits + s->cluster_bits);
- if (l1_index >= s->l1_size) {
- ret = grow_l1_table(bs, l1_index + 1);
- if (ret < 0)
- return 0;
- }
- l2_offset = s->l1_table[l1_index];
-
- /* seek the l2 table of the given l2 offset */
-
- if (l2_offset & QCOW_OFLAG_COPIED) {
- /* load the l2 table in memory */
- l2_offset &= ~QCOW_OFLAG_COPIED;
- l2_table = l2_load(bs, l2_offset);
- if (l2_table == NULL)
- return 0;
- } else {
- if (l2_offset)
- free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
- l2_table = l2_allocate(bs, l1_index);
- if (l2_table == NULL)
- return 0;
- l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED;
- }
-
- /* find the cluster offset for the given disk offset */
-
- l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
-
- *new_l2_table = l2_table;
- *new_l2_offset = l2_offset;
- *new_l2_index = l2_index;
-
- return 1;
-}
-
-/*
- * alloc_compressed_cluster_offset
- *
- * For a given offset of the disk image, return cluster offset in
- * qcow2 file.
- *
- * If the offset is not found, allocate a new compressed cluster.
- *
- * Return the cluster offset if successful,
- * Return 0, otherwise.
- *
- */
-
-static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
- uint64_t offset,
- int compressed_size)
-{
- BDRVQcowState *s = bs->opaque;
- int l2_index, ret;
- uint64_t l2_offset, *l2_table, cluster_offset;
- int nb_csectors;
-
- ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
- if (ret == 0)
- return 0;
-
- cluster_offset = be64_to_cpu(l2_table[l2_index]);
- if (cluster_offset & QCOW_OFLAG_COPIED)
- return cluster_offset & ~QCOW_OFLAG_COPIED;
-
- if (cluster_offset)
- free_any_clusters(bs, cluster_offset, 1);
-
- cluster_offset = alloc_bytes(bs, compressed_size);
- nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
- (cluster_offset >> 9);
-
- cluster_offset |= QCOW_OFLAG_COMPRESSED |
- ((uint64_t)nb_csectors << s->csize_shift);
-
- /* update L2 table */
-
- /* compressed clusters never have the copied flag */
-
- l2_table[l2_index] = cpu_to_be64(cluster_offset);
- if (bdrv_pwrite(s->hd,
- l2_offset + l2_index * sizeof(uint64_t),
- l2_table + l2_index,
- sizeof(uint64_t)) != sizeof(uint64_t))
- return 0;
-
- return cluster_offset;
-}
-
-typedef struct QCowL2Meta
-{
- uint64_t offset;
- int n_start;
- int nb_available;
- int nb_clusters;
-} QCowL2Meta;
-
-static int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
- QCowL2Meta *m)
-{
- BDRVQcowState *s = bs->opaque;
- int i, j = 0, l2_index, ret;
- uint64_t *old_cluster, start_sect, l2_offset, *l2_table;
-
- if (m->nb_clusters == 0)
- return 0;
-
- old_cluster = qemu_malloc(m->nb_clusters * sizeof(uint64_t));
-
- /* copy content of unmodified sectors */
- start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9;
- if (m->n_start) {
- ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start);
- if (ret < 0)
- goto err;
- }
-
- if (m->nb_available & (s->cluster_sectors - 1)) {
- uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1);
- ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9),
- m->nb_available - end, s->cluster_sectors);
- if (ret < 0)
- goto err;
- }
-
- ret = -EIO;
- /* update L2 table */
- if (!get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index))
- goto err;
-
- for (i = 0; i < m->nb_clusters; i++) {
- /* if two concurrent writes happen to the same unallocated cluster
- * each write allocates separate cluster and writes data concurrently.
- * The first one to complete updates l2 table with pointer to its
- * cluster the second one has to do RMW (which is done above by
- * copy_sectors()), update l2 table with its cluster pointer and free
- * old cluster. This is what this loop does */
- if(l2_table[l2_index + i] != 0)
- old_cluster[j++] = l2_table[l2_index + i];
-
- l2_table[l2_index + i] = cpu_to_be64((cluster_offset +
- (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);
- }
-
- if (bdrv_pwrite(s->hd, l2_offset + l2_index * sizeof(uint64_t),
- l2_table + l2_index, m->nb_clusters * sizeof(uint64_t)) !=
- m->nb_clusters * sizeof(uint64_t))
- goto err;
-
- for (i = 0; i < j; i++)
- free_any_clusters(bs, be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED,
- 1);
-
- ret = 0;
-err:
- qemu_free(old_cluster);
- return ret;
- }
-
-/*
- * alloc_cluster_offset
- *
- * For a given offset of the disk image, return cluster offset in
- * qcow2 file.
- *
- * If the offset is not found, allocate a new cluster.
- *
- * Return the cluster offset if successful,
- * Return 0, otherwise.
- *
- */
-
-static uint64_t alloc_cluster_offset(BlockDriverState *bs,
- uint64_t offset,
- int n_start, int n_end,
- int *num, QCowL2Meta *m)
-{
- BDRVQcowState *s = bs->opaque;
- int l2_index, ret;
- uint64_t l2_offset, *l2_table, cluster_offset;
- int nb_clusters, i = 0;
-
- ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
- if (ret == 0)
- return 0;
-
- nb_clusters = size_to_clusters(s, n_end << 9);
-
- nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
-
- cluster_offset = be64_to_cpu(l2_table[l2_index]);
-
- /* We keep all QCOW_OFLAG_COPIED clusters */
-
- if (cluster_offset & QCOW_OFLAG_COPIED) {
- nb_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size,
- &l2_table[l2_index], 0, 0);
-
- cluster_offset &= ~QCOW_OFLAG_COPIED;
- m->nb_clusters = 0;
-
- goto out;
- }
-
- /* for the moment, multiple compressed clusters are not managed */
-
- if (cluster_offset & QCOW_OFLAG_COMPRESSED)
- nb_clusters = 1;
-
- /* how many available clusters ? */
-
- while (i < nb_clusters) {
- i += count_contiguous_clusters(nb_clusters - i, s->cluster_size,
- &l2_table[l2_index], i, 0);
-
- if(be64_to_cpu(l2_table[l2_index + i]))
- break;
-
- i += count_contiguous_free_clusters(nb_clusters - i,
- &l2_table[l2_index + i]);
-
- cluster_offset = be64_to_cpu(l2_table[l2_index + i]);
-
- if ((cluster_offset & QCOW_OFLAG_COPIED) ||
- (cluster_offset & QCOW_OFLAG_COMPRESSED))
- break;
- }
- nb_clusters = i;
-
- /* allocate a new cluster */
-
- cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size);
-
- /* save info needed for meta data update */
- m->offset = offset;
- m->n_start = n_start;
- m->nb_clusters = nb_clusters;
-
-out:
- m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end);
-
- *num = m->nb_available - n_start;
-
- return cluster_offset;
-}
-
static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, int *pnum)
{
@@ -1018,59 +348,9 @@ static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num,
return (cluster_offset != 0);
}
-static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
- const uint8_t *buf, int buf_size)
-{
- z_stream strm1, *strm = &strm1;
- int ret, out_len;
-
- memset(strm, 0, sizeof(*strm));
-
- strm->next_in = (uint8_t *)buf;
- strm->avail_in = buf_size;
- strm->next_out = out_buf;
- strm->avail_out = out_buf_size;
-
- ret = inflateInit2(strm, -12);
- if (ret != Z_OK)
- return -1;
- ret = inflate(strm, Z_FINISH);
- out_len = strm->next_out - out_buf;
- if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
- out_len != out_buf_size) {
- inflateEnd(strm);
- return -1;
- }
- inflateEnd(strm);
- return 0;
-}
-
-static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
-{
- int ret, csize, nb_csectors, sector_offset;
- uint64_t coffset;
-
- coffset = cluster_offset & s->cluster_offset_mask;
- if (s->cluster_cache_offset != coffset) {
- nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
- sector_offset = coffset & 511;
- csize = nb_csectors * 512 - sector_offset;
- ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors);
- if (ret < 0) {
- return -1;
- }
- if (decompress_buffer(s->cluster_cache, s->cluster_size,
- s->cluster_data + sector_offset, csize) < 0) {
- return -1;
- }
- s->cluster_cache_offset = coffset;
- }
- return 0;
-}
-
/* handle reading after the end of the backing file */
-static int backing_read1(BlockDriverState *bs,
- int64_t sector_num, uint8_t *buf, int nb_sectors)
+int backing_read1(BlockDriverState *bs,
+ int64_t sector_num, uint8_t *buf, int nb_sectors)
{
int n1;
if ((sector_num + nb_sectors) <= bs->total_sectors)
@@ -1083,49 +363,6 @@ static int backing_read1(BlockDriverState *bs,
return n1;
}
-static int qcow_read(BlockDriverState *bs, int64_t sector_num,
- uint8_t *buf, int nb_sectors)
-{
- BDRVQcowState *s = bs->opaque;
- int ret, index_in_cluster, n, n1;
- uint64_t cluster_offset;
-
- while (nb_sectors > 0) {
- n = nb_sectors;
- cluster_offset = get_cluster_offset(bs, sector_num << 9, &n);
- index_in_cluster = sector_num & (s->cluster_sectors - 1);
- if (!cluster_offset) {
- if (bs->backing_hd) {
- /* read from the base image */
- n1 = backing_read1(bs->backing_hd, sector_num, buf, n);
- if (n1 > 0) {
- ret = bdrv_read(bs->backing_hd, sector_num, buf, n1);
- if (ret < 0)
- return -1;
- }
- } else {
- memset(buf, 0, 512 * n);
- }
- } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
- if (decompress_cluster(s, cluster_offset) < 0)
- return -1;
- memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);
- } else {
- ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);
- if (ret != n * 512)
- return -1;
- if (s->crypt_method) {
- encrypt_sectors(s, sector_num, buf, buf, n, 0,
- &s->aes_decrypt_key);
- }
- }
- nb_sectors -= n;
- sector_num += n;
- buf += n * 512;
- }
- return 0;
-}
-
typedef struct QCowAIOCB {
BlockDriverAIOCB common;
int64_t sector_num;
diff --git a/block/qcow2.h b/block/qcow2.h
index 3a34212..367d9bd 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -124,7 +124,16 @@ typedef struct QCowCreateState {
int64_t refcount_block_offset;
} QCowCreateState;
-static int size_to_clusters(BDRVQcowState *s, int64_t size)
+/* XXX This could be private for qcow2-cluster.c */
+typedef struct QCowL2Meta
+{
+ uint64_t offset;
+ int n_start;
+ int nb_available;
+ int nb_clusters;
+} QCowL2Meta;
+
+static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
{
return (size + (s->cluster_size - 1)) >> s->cluster_bits;
}
@@ -133,6 +142,8 @@ static int size_to_clusters(BDRVQcowState *s, int64_t size)
/* qcow2.c functions */
void l2_cache_reset(BlockDriverState *bs);
+int backing_read1(BlockDriverState *bs,
+ int64_t sector_num, uint8_t *buf, int nb_sectors);
/* qcow2-refcount.c functions */
int refcount_init(BlockDriverState *bs);
@@ -141,7 +152,9 @@ void refcount_close(BlockDriverState *bs);
int64_t alloc_clusters(BlockDriverState *bs, int64_t size);
int64_t alloc_bytes(BlockDriverState *bs, int size);
void free_clusters(BlockDriverState *bs,
- int64_t offset, int64_t size);
+ int64_t offset, int64_t size);
+void free_any_clusters(BlockDriverState *bs,
+ uint64_t cluster_offset, int nb_clusters);
void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size);
int update_snapshot_refcount(BlockDriverState *bs,
@@ -151,4 +164,24 @@ int update_snapshot_refcount(BlockDriverState *bs,
int check_refcounts(BlockDriverState *bs);
+/* qcow2-cluster.c functions */
+int grow_l1_table(BlockDriverState *bs, int min_size);
+int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
+void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+ uint8_t *out_buf, const uint8_t *in_buf,
+ int nb_sectors, int enc,
+ const AES_KEY *key);
+
+uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int *num);
+uint64_t alloc_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int n_start, int n_end,
+ int *num, QCowL2Meta *m);
+uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int compressed_size);
+
+int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
+ QCowL2Meta *m);
+
#endif
--
1.6.0.6
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH 3/4] qcow2: Split out snapshot functions
2009-05-28 14:07 [Qemu-devel] [PATCH 0/4] Split qcow2 driver Kevin Wolf
2009-05-28 14:07 ` [Qemu-devel] [PATCH 1/4] qcow2: Split out refcount handling Kevin Wolf
2009-05-28 14:07 ` [Qemu-devel] [PATCH 2/4] qcow2: Split out guest cluster functions Kevin Wolf
@ 2009-05-28 14:07 ` Kevin Wolf
2009-05-28 14:07 ` [Qemu-devel] [PATCH 4/4] qcow2: Rename global functions Kevin Wolf
2009-05-28 14:39 ` [Qemu-devel] [PATCH 0/4] Split qcow2 driver Anthony Liguori
4 siblings, 0 replies; 9+ messages in thread
From: Kevin Wolf @ 2009-05-28 14:07 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf
qcow2-snapshot.c contains the code related to snapshotting.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
Makefile | 1 +
block/qcow2-snapshot.c | 405 ++++++++++++++++++++++++++++++++++++++++++++++++
block/qcow2.c | 392 ----------------------------------------------
block/qcow2.h | 16 ++
4 files changed, 422 insertions(+), 392 deletions(-)
create mode 100644 block/qcow2-snapshot.c
diff --git a/Makefile b/Makefile
index 7bc37ce..32e2f68 100644
--- a/Makefile
+++ b/Makefile
@@ -69,6 +69,7 @@ BLOCK_OBJS=cutils.o cache-utils.o qemu-malloc.o qemu-option.o module.o
BLOCK_OBJS+=block/cow.o block/qcow.o aes.o block/vmdk.o block/cloop.o
BLOCK_OBJS+=block/dmg.o block/bochs.o block/vpc.o block/vvfat.o
BLOCK_OBJS+=block/qcow2.o block/qcow2-refcount.o block/qcow2-cluster.o
+BLOCK_OBJS+=block/qcow2-snapshot.o
BLOCK_OBJS+=block/parallels.o block/nbd.o
BLOCK_OBJS+=nbd.o block.o aio.o
diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c
new file mode 100644
index 0000000..2883e50
--- /dev/null
+++ b/block/qcow2-snapshot.c
@@ -0,0 +1,405 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu-common.h"
+#include "block_int.h"
+#include "block/qcow2.h"
+
+typedef struct __attribute__((packed)) QCowSnapshotHeader {
+ /* header is 8 byte aligned */
+ uint64_t l1_table_offset;
+
+ uint32_t l1_size;
+ uint16_t id_str_size;
+ uint16_t name_size;
+
+ uint32_t date_sec;
+ uint32_t date_nsec;
+
+ uint64_t vm_clock_nsec;
+
+ uint32_t vm_state_size;
+ uint32_t extra_data_size; /* for extension */
+ /* extra data follows */
+ /* id_str follows */
+ /* name follows */
+} QCowSnapshotHeader;
+
+void qcow_free_snapshots(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ int i;
+
+ for(i = 0; i < s->nb_snapshots; i++) {
+ qemu_free(s->snapshots[i].name);
+ qemu_free(s->snapshots[i].id_str);
+ }
+ qemu_free(s->snapshots);
+ s->snapshots = NULL;
+ s->nb_snapshots = 0;
+}
+
+int qcow_read_snapshots(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ QCowSnapshotHeader h;
+ QCowSnapshot *sn;
+ int i, id_str_size, name_size;
+ int64_t offset;
+ uint32_t extra_data_size;
+
+ if (!s->nb_snapshots) {
+ s->snapshots = NULL;
+ s->snapshots_size = 0;
+ return 0;
+ }
+
+ offset = s->snapshots_offset;
+ s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot));
+ for(i = 0; i < s->nb_snapshots; i++) {
+ offset = align_offset(offset, 8);
+ if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h))
+ goto fail;
+ offset += sizeof(h);
+ sn = s->snapshots + i;
+ sn->l1_table_offset = be64_to_cpu(h.l1_table_offset);
+ sn->l1_size = be32_to_cpu(h.l1_size);
+ sn->vm_state_size = be32_to_cpu(h.vm_state_size);
+ sn->date_sec = be32_to_cpu(h.date_sec);
+ sn->date_nsec = be32_to_cpu(h.date_nsec);
+ sn->vm_clock_nsec = be64_to_cpu(h.vm_clock_nsec);
+ extra_data_size = be32_to_cpu(h.extra_data_size);
+
+ id_str_size = be16_to_cpu(h.id_str_size);
+ name_size = be16_to_cpu(h.name_size);
+
+ offset += extra_data_size;
+
+ sn->id_str = qemu_malloc(id_str_size + 1);
+ if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
+ goto fail;
+ offset += id_str_size;
+ sn->id_str[id_str_size] = '\0';
+
+ sn->name = qemu_malloc(name_size + 1);
+ if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size)
+ goto fail;
+ offset += name_size;
+ sn->name[name_size] = '\0';
+ }
+ s->snapshots_size = offset - s->snapshots_offset;
+ return 0;
+ fail:
+ qcow_free_snapshots(bs);
+ return -1;
+}
+
+/* add at the end of the file a new list of snapshots */
+static int qcow_write_snapshots(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ QCowSnapshot *sn;
+ QCowSnapshotHeader h;
+ int i, name_size, id_str_size, snapshots_size;
+ uint64_t data64;
+ uint32_t data32;
+ int64_t offset, snapshots_offset;
+
+ /* compute the size of the snapshots */
+ offset = 0;
+ for(i = 0; i < s->nb_snapshots; i++) {
+ sn = s->snapshots + i;
+ offset = align_offset(offset, 8);
+ offset += sizeof(h);
+ offset += strlen(sn->id_str);
+ offset += strlen(sn->name);
+ }
+ snapshots_size = offset;
+
+ snapshots_offset = alloc_clusters(bs, snapshots_size);
+ offset = snapshots_offset;
+
+ for(i = 0; i < s->nb_snapshots; i++) {
+ sn = s->snapshots + i;
+ memset(&h, 0, sizeof(h));
+ h.l1_table_offset = cpu_to_be64(sn->l1_table_offset);
+ h.l1_size = cpu_to_be32(sn->l1_size);
+ h.vm_state_size = cpu_to_be32(sn->vm_state_size);
+ h.date_sec = cpu_to_be32(sn->date_sec);
+ h.date_nsec = cpu_to_be32(sn->date_nsec);
+ h.vm_clock_nsec = cpu_to_be64(sn->vm_clock_nsec);
+
+ id_str_size = strlen(sn->id_str);
+ name_size = strlen(sn->name);
+ h.id_str_size = cpu_to_be16(id_str_size);
+ h.name_size = cpu_to_be16(name_size);
+ offset = align_offset(offset, 8);
+ if (bdrv_pwrite(s->hd, offset, &h, sizeof(h)) != sizeof(h))
+ goto fail;
+ offset += sizeof(h);
+ if (bdrv_pwrite(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
+ goto fail;
+ offset += id_str_size;
+ if (bdrv_pwrite(s->hd, offset, sn->name, name_size) != name_size)
+ goto fail;
+ offset += name_size;
+ }
+
+ /* update the various header fields */
+ data64 = cpu_to_be64(snapshots_offset);
+ if (bdrv_pwrite(s->hd, offsetof(QCowHeader, snapshots_offset),
+ &data64, sizeof(data64)) != sizeof(data64))
+ goto fail;
+ data32 = cpu_to_be32(s->nb_snapshots);
+ if (bdrv_pwrite(s->hd, offsetof(QCowHeader, nb_snapshots),
+ &data32, sizeof(data32)) != sizeof(data32))
+ goto fail;
+
+ /* free the old snapshot table */
+ free_clusters(bs, s->snapshots_offset, s->snapshots_size);
+ s->snapshots_offset = snapshots_offset;
+ s->snapshots_size = snapshots_size;
+ return 0;
+ fail:
+ return -1;
+}
+
+static void find_new_snapshot_id(BlockDriverState *bs,
+ char *id_str, int id_str_size)
+{
+ BDRVQcowState *s = bs->opaque;
+ QCowSnapshot *sn;
+ int i, id, id_max = 0;
+
+ for(i = 0; i < s->nb_snapshots; i++) {
+ sn = s->snapshots + i;
+ id = strtoul(sn->id_str, NULL, 10);
+ if (id > id_max)
+ id_max = id;
+ }
+ snprintf(id_str, id_str_size, "%d", id_max + 1);
+}
+
+static int find_snapshot_by_id(BlockDriverState *bs, const char *id_str)
+{
+ BDRVQcowState *s = bs->opaque;
+ int i;
+
+ for(i = 0; i < s->nb_snapshots; i++) {
+ if (!strcmp(s->snapshots[i].id_str, id_str))
+ return i;
+ }
+ return -1;
+}
+
+static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name)
+{
+ BDRVQcowState *s = bs->opaque;
+ int i, ret;
+
+ ret = find_snapshot_by_id(bs, name);
+ if (ret >= 0)
+ return ret;
+ for(i = 0; i < s->nb_snapshots; i++) {
+ if (!strcmp(s->snapshots[i].name, name))
+ return i;
+ }
+ return -1;
+}
+
+/* if no id is provided, a new one is constructed */
+int qcow_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
+{
+ BDRVQcowState *s = bs->opaque;
+ QCowSnapshot *snapshots1, sn1, *sn = &sn1;
+ int i, ret;
+ uint64_t *l1_table = NULL;
+
+ memset(sn, 0, sizeof(*sn));
+
+ if (sn_info->id_str[0] == '\0') {
+ /* compute a new id */
+ find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str));
+ }
+
+ /* check that the ID is unique */
+ if (find_snapshot_by_id(bs, sn_info->id_str) >= 0)
+ return -ENOENT;
+
+ sn->id_str = qemu_strdup(sn_info->id_str);
+ if (!sn->id_str)
+ goto fail;
+ sn->name = qemu_strdup(sn_info->name);
+ if (!sn->name)
+ goto fail;
+ sn->vm_state_size = sn_info->vm_state_size;
+ sn->date_sec = sn_info->date_sec;
+ sn->date_nsec = sn_info->date_nsec;
+ sn->vm_clock_nsec = sn_info->vm_clock_nsec;
+
+ ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1);
+ if (ret < 0)
+ goto fail;
+
+ /* create the L1 table of the snapshot */
+ sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
+ sn->l1_size = s->l1_size;
+
+ l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
+ for(i = 0; i < s->l1_size; i++) {
+ l1_table[i] = cpu_to_be64(s->l1_table[i]);
+ }
+ if (bdrv_pwrite(s->hd, sn->l1_table_offset,
+ l1_table, s->l1_size * sizeof(uint64_t)) !=
+ (s->l1_size * sizeof(uint64_t)))
+ goto fail;
+ qemu_free(l1_table);
+ l1_table = NULL;
+
+ snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot));
+ if (s->snapshots) {
+ memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot));
+ qemu_free(s->snapshots);
+ }
+ s->snapshots = snapshots1;
+ s->snapshots[s->nb_snapshots++] = *sn;
+
+ if (qcow_write_snapshots(bs) < 0)
+ goto fail;
+#ifdef DEBUG_ALLOC
+ check_refcounts(bs);
+#endif
+ return 0;
+ fail:
+ qemu_free(sn->name);
+ qemu_free(l1_table);
+ return -1;
+}
+
+/* copy the snapshot 'snapshot_name' into the current disk image */
+int qcow_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
+{
+ BDRVQcowState *s = bs->opaque;
+ QCowSnapshot *sn;
+ int i, snapshot_index, l1_size2;
+
+ snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id);
+ if (snapshot_index < 0)
+ return -ENOENT;
+ sn = &s->snapshots[snapshot_index];
+
+ if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0)
+ goto fail;
+
+ if (grow_l1_table(bs, sn->l1_size) < 0)
+ goto fail;
+
+ s->l1_size = sn->l1_size;
+ l1_size2 = s->l1_size * sizeof(uint64_t);
+ /* copy the snapshot l1 table to the current l1 table */
+ if (bdrv_pread(s->hd, sn->l1_table_offset,
+ s->l1_table, l1_size2) != l1_size2)
+ goto fail;
+ if (bdrv_pwrite(s->hd, s->l1_table_offset,
+ s->l1_table, l1_size2) != l1_size2)
+ goto fail;
+ for(i = 0;i < s->l1_size; i++) {
+ be64_to_cpus(&s->l1_table[i]);
+ }
+
+ if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0)
+ goto fail;
+
+#ifdef DEBUG_ALLOC
+ check_refcounts(bs);
+#endif
+ return 0;
+ fail:
+ return -EIO;
+}
+
+int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
+{
+ BDRVQcowState *s = bs->opaque;
+ QCowSnapshot *sn;
+ int snapshot_index, ret;
+
+ snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id);
+ if (snapshot_index < 0)
+ return -ENOENT;
+ sn = &s->snapshots[snapshot_index];
+
+ ret = update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1);
+ if (ret < 0)
+ return ret;
+ /* must update the copied flag on the current cluster offsets */
+ ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
+ if (ret < 0)
+ return ret;
+ free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t));
+
+ qemu_free(sn->id_str);
+ qemu_free(sn->name);
+ memmove(sn, sn + 1, (s->nb_snapshots - snapshot_index - 1) * sizeof(*sn));
+ s->nb_snapshots--;
+ ret = qcow_write_snapshots(bs);
+ if (ret < 0) {
+ /* XXX: restore snapshot if error ? */
+ return ret;
+ }
+#ifdef DEBUG_ALLOC
+ check_refcounts(bs);
+#endif
+ return 0;
+}
+
+int qcow_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab)
+{
+ BDRVQcowState *s = bs->opaque;
+ QEMUSnapshotInfo *sn_tab, *sn_info;
+ QCowSnapshot *sn;
+ int i;
+
+ if (!s->nb_snapshots) {
+ *psn_tab = NULL;
+ return s->nb_snapshots;
+ }
+
+ sn_tab = qemu_mallocz(s->nb_snapshots * sizeof(QEMUSnapshotInfo));
+ for(i = 0; i < s->nb_snapshots; i++) {
+ sn_info = sn_tab + i;
+ sn = s->snapshots + i;
+ pstrcpy(sn_info->id_str, sizeof(sn_info->id_str),
+ sn->id_str);
+ pstrcpy(sn_info->name, sizeof(sn_info->name),
+ sn->name);
+ sn_info->vm_state_size = sn->vm_state_size;
+ sn_info->date_sec = sn->date_sec;
+ sn_info->date_nsec = sn->date_nsec;
+ sn_info->vm_clock_nsec = sn->vm_clock_nsec;
+ }
+ *psn_tab = sn_tab;
+ return s->nb_snapshots;
+}
+
diff --git a/block/qcow2.c b/block/qcow2.c
index a91aaeb..febdf67 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -57,29 +57,6 @@ typedef struct {
#define QCOW_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA
-typedef struct __attribute__((packed)) QCowSnapshotHeader {
- /* header is 8 byte aligned */
- uint64_t l1_table_offset;
-
- uint32_t l1_size;
- uint16_t id_str_size;
- uint16_t name_size;
-
- uint32_t date_sec;
- uint32_t date_nsec;
-
- uint64_t vm_clock_nsec;
-
- uint32_t vm_state_size;
- uint32_t extra_data_size; /* for extension */
- /* extra data follows */
- /* id_str follows */
- /* name follows */
-} QCowSnapshotHeader;
-
-
-static int qcow_read_snapshots(BlockDriverState *bs);
-static void qcow_free_snapshots(BlockDriverState *bs);
static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
{
@@ -331,12 +308,6 @@ static int qcow_set_key(BlockDriverState *bs, const char *key)
return 0;
}
-static int64_t align_offset(int64_t offset, int n)
-{
- offset = (offset + n - 1) & ~(n - 1);
- return offset;
-}
-
static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, int *pnum)
{
@@ -936,369 +907,6 @@ static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
return 0;
}
-/*********************************************************/
-/* snapshot support */
-
-
-static void qcow_free_snapshots(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- int i;
-
- for(i = 0; i < s->nb_snapshots; i++) {
- qemu_free(s->snapshots[i].name);
- qemu_free(s->snapshots[i].id_str);
- }
- qemu_free(s->snapshots);
- s->snapshots = NULL;
- s->nb_snapshots = 0;
-}
-
-static int qcow_read_snapshots(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- QCowSnapshotHeader h;
- QCowSnapshot *sn;
- int i, id_str_size, name_size;
- int64_t offset;
- uint32_t extra_data_size;
-
- if (!s->nb_snapshots) {
- s->snapshots = NULL;
- s->snapshots_size = 0;
- return 0;
- }
-
- offset = s->snapshots_offset;
- s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot));
- for(i = 0; i < s->nb_snapshots; i++) {
- offset = align_offset(offset, 8);
- if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h))
- goto fail;
- offset += sizeof(h);
- sn = s->snapshots + i;
- sn->l1_table_offset = be64_to_cpu(h.l1_table_offset);
- sn->l1_size = be32_to_cpu(h.l1_size);
- sn->vm_state_size = be32_to_cpu(h.vm_state_size);
- sn->date_sec = be32_to_cpu(h.date_sec);
- sn->date_nsec = be32_to_cpu(h.date_nsec);
- sn->vm_clock_nsec = be64_to_cpu(h.vm_clock_nsec);
- extra_data_size = be32_to_cpu(h.extra_data_size);
-
- id_str_size = be16_to_cpu(h.id_str_size);
- name_size = be16_to_cpu(h.name_size);
-
- offset += extra_data_size;
-
- sn->id_str = qemu_malloc(id_str_size + 1);
- if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
- goto fail;
- offset += id_str_size;
- sn->id_str[id_str_size] = '\0';
-
- sn->name = qemu_malloc(name_size + 1);
- if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size)
- goto fail;
- offset += name_size;
- sn->name[name_size] = '\0';
- }
- s->snapshots_size = offset - s->snapshots_offset;
- return 0;
- fail:
- qcow_free_snapshots(bs);
- return -1;
-}
-
-/* add at the end of the file a new list of snapshots */
-static int qcow_write_snapshots(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- QCowSnapshot *sn;
- QCowSnapshotHeader h;
- int i, name_size, id_str_size, snapshots_size;
- uint64_t data64;
- uint32_t data32;
- int64_t offset, snapshots_offset;
-
- /* compute the size of the snapshots */
- offset = 0;
- for(i = 0; i < s->nb_snapshots; i++) {
- sn = s->snapshots + i;
- offset = align_offset(offset, 8);
- offset += sizeof(h);
- offset += strlen(sn->id_str);
- offset += strlen(sn->name);
- }
- snapshots_size = offset;
-
- snapshots_offset = alloc_clusters(bs, snapshots_size);
- offset = snapshots_offset;
-
- for(i = 0; i < s->nb_snapshots; i++) {
- sn = s->snapshots + i;
- memset(&h, 0, sizeof(h));
- h.l1_table_offset = cpu_to_be64(sn->l1_table_offset);
- h.l1_size = cpu_to_be32(sn->l1_size);
- h.vm_state_size = cpu_to_be32(sn->vm_state_size);
- h.date_sec = cpu_to_be32(sn->date_sec);
- h.date_nsec = cpu_to_be32(sn->date_nsec);
- h.vm_clock_nsec = cpu_to_be64(sn->vm_clock_nsec);
-
- id_str_size = strlen(sn->id_str);
- name_size = strlen(sn->name);
- h.id_str_size = cpu_to_be16(id_str_size);
- h.name_size = cpu_to_be16(name_size);
- offset = align_offset(offset, 8);
- if (bdrv_pwrite(s->hd, offset, &h, sizeof(h)) != sizeof(h))
- goto fail;
- offset += sizeof(h);
- if (bdrv_pwrite(s->hd, offset, sn->id_str, id_str_size) != id_str_size)
- goto fail;
- offset += id_str_size;
- if (bdrv_pwrite(s->hd, offset, sn->name, name_size) != name_size)
- goto fail;
- offset += name_size;
- }
-
- /* update the various header fields */
- data64 = cpu_to_be64(snapshots_offset);
- if (bdrv_pwrite(s->hd, offsetof(QCowHeader, snapshots_offset),
- &data64, sizeof(data64)) != sizeof(data64))
- goto fail;
- data32 = cpu_to_be32(s->nb_snapshots);
- if (bdrv_pwrite(s->hd, offsetof(QCowHeader, nb_snapshots),
- &data32, sizeof(data32)) != sizeof(data32))
- goto fail;
-
- /* free the old snapshot table */
- free_clusters(bs, s->snapshots_offset, s->snapshots_size);
- s->snapshots_offset = snapshots_offset;
- s->snapshots_size = snapshots_size;
- return 0;
- fail:
- return -1;
-}
-
-static void find_new_snapshot_id(BlockDriverState *bs,
- char *id_str, int id_str_size)
-{
- BDRVQcowState *s = bs->opaque;
- QCowSnapshot *sn;
- int i, id, id_max = 0;
-
- for(i = 0; i < s->nb_snapshots; i++) {
- sn = s->snapshots + i;
- id = strtoul(sn->id_str, NULL, 10);
- if (id > id_max)
- id_max = id;
- }
- snprintf(id_str, id_str_size, "%d", id_max + 1);
-}
-
-static int find_snapshot_by_id(BlockDriverState *bs, const char *id_str)
-{
- BDRVQcowState *s = bs->opaque;
- int i;
-
- for(i = 0; i < s->nb_snapshots; i++) {
- if (!strcmp(s->snapshots[i].id_str, id_str))
- return i;
- }
- return -1;
-}
-
-static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name)
-{
- BDRVQcowState *s = bs->opaque;
- int i, ret;
-
- ret = find_snapshot_by_id(bs, name);
- if (ret >= 0)
- return ret;
- for(i = 0; i < s->nb_snapshots; i++) {
- if (!strcmp(s->snapshots[i].name, name))
- return i;
- }
- return -1;
-}
-
-/* if no id is provided, a new one is constructed */
-static int qcow_snapshot_create(BlockDriverState *bs,
- QEMUSnapshotInfo *sn_info)
-{
- BDRVQcowState *s = bs->opaque;
- QCowSnapshot *snapshots1, sn1, *sn = &sn1;
- int i, ret;
- uint64_t *l1_table = NULL;
-
- memset(sn, 0, sizeof(*sn));
-
- if (sn_info->id_str[0] == '\0') {
- /* compute a new id */
- find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str));
- }
-
- /* check that the ID is unique */
- if (find_snapshot_by_id(bs, sn_info->id_str) >= 0)
- return -ENOENT;
-
- sn->id_str = qemu_strdup(sn_info->id_str);
- if (!sn->id_str)
- goto fail;
- sn->name = qemu_strdup(sn_info->name);
- if (!sn->name)
- goto fail;
- sn->vm_state_size = sn_info->vm_state_size;
- sn->date_sec = sn_info->date_sec;
- sn->date_nsec = sn_info->date_nsec;
- sn->vm_clock_nsec = sn_info->vm_clock_nsec;
-
- ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1);
- if (ret < 0)
- goto fail;
-
- /* create the L1 table of the snapshot */
- sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
- sn->l1_size = s->l1_size;
-
- l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
- for(i = 0; i < s->l1_size; i++) {
- l1_table[i] = cpu_to_be64(s->l1_table[i]);
- }
- if (bdrv_pwrite(s->hd, sn->l1_table_offset,
- l1_table, s->l1_size * sizeof(uint64_t)) !=
- (s->l1_size * sizeof(uint64_t)))
- goto fail;
- qemu_free(l1_table);
- l1_table = NULL;
-
- snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot));
- if (s->snapshots) {
- memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot));
- qemu_free(s->snapshots);
- }
- s->snapshots = snapshots1;
- s->snapshots[s->nb_snapshots++] = *sn;
-
- if (qcow_write_snapshots(bs) < 0)
- goto fail;
-#ifdef DEBUG_ALLOC
- check_refcounts(bs);
-#endif
- return 0;
- fail:
- qemu_free(sn->name);
- qemu_free(l1_table);
- return -1;
-}
-
-/* copy the snapshot 'snapshot_name' into the current disk image */
-static int qcow_snapshot_goto(BlockDriverState *bs,
- const char *snapshot_id)
-{
- BDRVQcowState *s = bs->opaque;
- QCowSnapshot *sn;
- int i, snapshot_index, l1_size2;
-
- snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id);
- if (snapshot_index < 0)
- return -ENOENT;
- sn = &s->snapshots[snapshot_index];
-
- if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0)
- goto fail;
-
- if (grow_l1_table(bs, sn->l1_size) < 0)
- goto fail;
-
- s->l1_size = sn->l1_size;
- l1_size2 = s->l1_size * sizeof(uint64_t);
- /* copy the snapshot l1 table to the current l1 table */
- if (bdrv_pread(s->hd, sn->l1_table_offset,
- s->l1_table, l1_size2) != l1_size2)
- goto fail;
- if (bdrv_pwrite(s->hd, s->l1_table_offset,
- s->l1_table, l1_size2) != l1_size2)
- goto fail;
- for(i = 0;i < s->l1_size; i++) {
- be64_to_cpus(&s->l1_table[i]);
- }
-
- if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0)
- goto fail;
-
-#ifdef DEBUG_ALLOC
- check_refcounts(bs);
-#endif
- return 0;
- fail:
- return -EIO;
-}
-
-static int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
-{
- BDRVQcowState *s = bs->opaque;
- QCowSnapshot *sn;
- int snapshot_index, ret;
-
- snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id);
- if (snapshot_index < 0)
- return -ENOENT;
- sn = &s->snapshots[snapshot_index];
-
- ret = update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1);
- if (ret < 0)
- return ret;
- /* must update the copied flag on the current cluster offsets */
- ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
- if (ret < 0)
- return ret;
- free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t));
-
- qemu_free(sn->id_str);
- qemu_free(sn->name);
- memmove(sn, sn + 1, (s->nb_snapshots - snapshot_index - 1) * sizeof(*sn));
- s->nb_snapshots--;
- ret = qcow_write_snapshots(bs);
- if (ret < 0) {
- /* XXX: restore snapshot if error ? */
- return ret;
- }
-#ifdef DEBUG_ALLOC
- check_refcounts(bs);
-#endif
- return 0;
-}
-
-static int qcow_snapshot_list(BlockDriverState *bs,
- QEMUSnapshotInfo **psn_tab)
-{
- BDRVQcowState *s = bs->opaque;
- QEMUSnapshotInfo *sn_tab, *sn_info;
- QCowSnapshot *sn;
- int i;
-
- if (!s->nb_snapshots) {
- *psn_tab = NULL;
- return s->nb_snapshots;
- }
-
- sn_tab = qemu_mallocz(s->nb_snapshots * sizeof(QEMUSnapshotInfo));
- for(i = 0; i < s->nb_snapshots; i++) {
- sn_info = sn_tab + i;
- sn = s->snapshots + i;
- pstrcpy(sn_info->id_str, sizeof(sn_info->id_str),
- sn->id_str);
- pstrcpy(sn_info->name, sizeof(sn_info->name),
- sn->name);
- sn_info->vm_state_size = sn->vm_state_size;
- sn_info->date_sec = sn->date_sec;
- sn_info->date_nsec = sn->date_nsec;
- sn_info->vm_clock_nsec = sn->vm_clock_nsec;
- }
- *psn_tab = sn_tab;
- return s->nb_snapshots;
-}
static int qcow_check(BlockDriverState *bs)
{
diff --git a/block/qcow2.h b/block/qcow2.h
index 367d9bd..397f21d 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -138,6 +138,13 @@ static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
return (size + (s->cluster_size - 1)) >> s->cluster_bits;
}
+static inline int64_t align_offset(int64_t offset, int n)
+{
+ offset = (offset + n - 1) & ~(n - 1);
+ return offset;
+}
+
+
// FIXME Need qcow2_ prefix to global functions
/* qcow2.c functions */
@@ -184,4 +191,13 @@ uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
QCowL2Meta *m);
+/* qcow2-snapshot.c functions */
+int qcow_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
+int qcow_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
+int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
+int qcow_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
+
+void qcow_free_snapshots(BlockDriverState *bs);
+int qcow_read_snapshots(BlockDriverState *bs);
+
#endif
--
1.6.0.6
^ permalink raw reply related [flat|nested] 9+ messages in thread* [Qemu-devel] [PATCH 4/4] qcow2: Rename global functions
2009-05-28 14:07 [Qemu-devel] [PATCH 0/4] Split qcow2 driver Kevin Wolf
` (2 preceding siblings ...)
2009-05-28 14:07 ` [Qemu-devel] [PATCH 3/4] qcow2: Split out snapshot functions Kevin Wolf
@ 2009-05-28 14:07 ` Kevin Wolf
2009-05-28 14:39 ` [Qemu-devel] [PATCH 0/4] Split qcow2 driver Anthony Liguori
4 siblings, 0 replies; 9+ messages in thread
From: Kevin Wolf @ 2009-05-28 14:07 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf
The qcow2 source is now split into several more manageable files. During the
conversion quite some functions that were static before needed to be changed to
be global to make the source compile again.
We were lucky enough not to get name conflicts with these additional global
names, but they are not nice. This patch adds a qcow2_ prefix to all of the
global functions in qcow2.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
block/qcow2-cluster.c | 63 ++++++++++++++++++++++++-----------------------
block/qcow2-refcount.c | 40 +++++++++++++++---------------
block/qcow2-snapshot.c | 34 +++++++++++++-------------
block/qcow2.c | 55 ++++++++++++++++++++++-------------------
block/qcow2.h | 54 ++++++++++++++++++++--------------------
5 files changed, 125 insertions(+), 121 deletions(-)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 494cc91..99215fa 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -28,7 +28,7 @@
#include "block_int.h"
#include "block/qcow2.h"
-int grow_l1_table(BlockDriverState *bs, int min_size)
+int qcow2_grow_l1_table(BlockDriverState *bs, int min_size)
{
BDRVQcowState *s = bs->opaque;
int new_l1_size, new_l1_size2, ret, i;
@@ -51,7 +51,7 @@ int grow_l1_table(BlockDriverState *bs, int min_size)
memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
/* write new table (align to cluster) */
- new_l1_table_offset = alloc_clusters(bs, new_l1_size2);
+ new_l1_table_offset = qcow2_alloc_clusters(bs, new_l1_size2);
for(i = 0; i < s->l1_size; i++)
new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
@@ -68,7 +68,7 @@ int grow_l1_table(BlockDriverState *bs, int min_size)
sizeof(data)) != sizeof(data))
goto fail;
qemu_free(s->l1_table);
- free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
+ qcow2_free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
s->l1_table_offset = new_l1_table_offset;
s->l1_table = new_l1_table;
s->l1_size = new_l1_size;
@@ -78,7 +78,7 @@ int grow_l1_table(BlockDriverState *bs, int min_size)
return -EIO;
}
-void l2_cache_reset(BlockDriverState *bs)
+void qcow2_l2_cache_reset(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
@@ -191,7 +191,7 @@ static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index)
/* allocate a new l2 entry */
- l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
+ l2_offset = qcow2_alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
/* update the L1 entry */
@@ -260,10 +260,10 @@ static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_tab
/* The crypt function is compatible with the linux cryptoloop
algorithm for < 4 GB images. NOTE: out_buf == in_buf is
supported */
-void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
- uint8_t *out_buf, const uint8_t *in_buf,
- int nb_sectors, int enc,
- const AES_KEY *key)
+void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+ uint8_t *out_buf, const uint8_t *in_buf,
+ int nb_sectors, int enc,
+ const AES_KEY *key)
{
union {
uint64_t ll[2];
@@ -292,12 +292,12 @@ static int qcow_read(BlockDriverState *bs, int64_t sector_num,
while (nb_sectors > 0) {
n = nb_sectors;
- cluster_offset = get_cluster_offset(bs, sector_num << 9, &n);
+ cluster_offset = qcow2_get_cluster_offset(bs, sector_num << 9, &n);
index_in_cluster = sector_num & (s->cluster_sectors - 1);
if (!cluster_offset) {
if (bs->backing_hd) {
/* read from the base image */
- n1 = backing_read1(bs->backing_hd, sector_num, buf, n);
+ n1 = qcow2_backing_read1(bs->backing_hd, sector_num, buf, n);
if (n1 > 0) {
ret = bdrv_read(bs->backing_hd, sector_num, buf, n1);
if (ret < 0)
@@ -307,7 +307,7 @@ static int qcow_read(BlockDriverState *bs, int64_t sector_num,
memset(buf, 0, 512 * n);
}
} else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
- if (decompress_cluster(s, cluster_offset) < 0)
+ if (qcow2_decompress_cluster(s, cluster_offset) < 0)
return -1;
memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);
} else {
@@ -315,7 +315,7 @@ static int qcow_read(BlockDriverState *bs, int64_t sector_num,
if (ret != n * 512)
return -1;
if (s->crypt_method) {
- encrypt_sectors(s, sector_num, buf, buf, n, 0,
+ qcow2_encrypt_sectors(s, sector_num, buf, buf, n, 0,
&s->aes_decrypt_key);
}
}
@@ -339,7 +339,7 @@ static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
if (ret < 0)
return ret;
if (s->crypt_method) {
- encrypt_sectors(s, start_sect + n_start,
+ qcow2_encrypt_sectors(s, start_sect + n_start,
s->cluster_data,
s->cluster_data, n, 1,
&s->aes_encrypt_key);
@@ -368,7 +368,8 @@ static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
*
*/
-uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int *num)
+uint64_t qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
+ int *num)
{
BDRVQcowState *s = bs->opaque;
int l1_index, l2_index;
@@ -466,7 +467,7 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
l1_index = offset >> (s->l2_bits + s->cluster_bits);
if (l1_index >= s->l1_size) {
- ret = grow_l1_table(bs, l1_index + 1);
+ ret = qcow2_grow_l1_table(bs, l1_index + 1);
if (ret < 0)
return 0;
}
@@ -482,7 +483,7 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
return 0;
} else {
if (l2_offset)
- free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
+ qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
l2_table = l2_allocate(bs, l1_index);
if (l2_table == NULL)
return 0;
@@ -513,9 +514,9 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
*
*/
-uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
- uint64_t offset,
- int compressed_size)
+uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int compressed_size)
{
BDRVQcowState *s = bs->opaque;
int l2_index, ret;
@@ -531,9 +532,9 @@ uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
return cluster_offset & ~QCOW_OFLAG_COPIED;
if (cluster_offset)
- free_any_clusters(bs, cluster_offset, 1);
+ qcow2_free_any_clusters(bs, cluster_offset, 1);
- cluster_offset = alloc_bytes(bs, compressed_size);
+ cluster_offset = qcow2_alloc_bytes(bs, compressed_size);
nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
(cluster_offset >> 9);
@@ -554,7 +555,7 @@ uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
return cluster_offset;
}
-int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
+int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
QCowL2Meta *m)
{
BDRVQcowState *s = bs->opaque;
@@ -607,8 +608,8 @@ int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
goto err;
for (i = 0; i < j; i++)
- free_any_clusters(bs, be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED,
- 1);
+ qcow2_free_any_clusters(bs,
+ be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED, 1);
ret = 0;
err:
@@ -629,10 +630,10 @@ err:
*
*/
-uint64_t alloc_cluster_offset(BlockDriverState *bs,
- uint64_t offset,
- int n_start, int n_end,
- int *num, QCowL2Meta *m)
+uint64_t qcow2_alloc_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int n_start, int n_end,
+ int *num, QCowL2Meta *m)
{
BDRVQcowState *s = bs->opaque;
int l2_index, ret;
@@ -688,7 +689,7 @@ uint64_t alloc_cluster_offset(BlockDriverState *bs,
/* allocate a new cluster */
- cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size);
+ cluster_offset = qcow2_alloc_clusters(bs, nb_clusters * s->cluster_size);
/* save info needed for meta data update */
m->offset = offset;
@@ -730,7 +731,7 @@ static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
return 0;
}
-int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
+int qcow2_decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
{
int ret, csize, nb_csectors, sector_offset;
uint64_t coffset;
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 3f461c6..b38390c 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -34,7 +34,7 @@ static int update_refcount(BlockDriverState *bs,
/*********************************************************/
/* refcount handling */
-int refcount_init(BlockDriverState *bs)
+int qcow2_refcount_init(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
int ret, refcount_table_size2, i;
@@ -55,7 +55,7 @@ int refcount_init(BlockDriverState *bs)
return -ENOMEM;
}
-void refcount_close(BlockDriverState *bs)
+void qcow2_refcount_close(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
qemu_free(s->refcount_block_cache);
@@ -154,10 +154,10 @@ static int grow_refcount_table(BlockDriverState *bs, int min_size)
s->refcount_table_offset = table_offset;
update_refcount(bs, table_offset, new_table_size2, 1);
- free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
+ qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
return 0;
fail:
- free_clusters(bs, table_offset, new_table_size2);
+ qcow2_free_clusters(bs, table_offset, new_table_size2);
qemu_free(new_table);
return -EIO;
}
@@ -334,7 +334,7 @@ retry:
return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
}
-int64_t alloc_clusters(BlockDriverState *bs, int64_t size)
+int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size)
{
int64_t offset;
@@ -345,7 +345,7 @@ int64_t alloc_clusters(BlockDriverState *bs, int64_t size)
/* only used to allocate compressed sectors. We try to allocate
contiguous sectors. size must be <= cluster_size */
-int64_t alloc_bytes(BlockDriverState *bs, int size)
+int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
{
BDRVQcowState *s = bs->opaque;
int64_t offset, cluster_offset;
@@ -353,7 +353,7 @@ int64_t alloc_bytes(BlockDriverState *bs, int size)
assert(size > 0 && size <= s->cluster_size);
if (s->free_byte_offset == 0) {
- s->free_byte_offset = alloc_clusters(bs, s->cluster_size);
+ s->free_byte_offset = qcow2_alloc_clusters(bs, s->cluster_size);
}
redo:
free_in_cluster = s->cluster_size -
@@ -368,7 +368,7 @@ int64_t alloc_bytes(BlockDriverState *bs, int size)
if ((offset & (s->cluster_size - 1)) != 0)
update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
} else {
- offset = alloc_clusters(bs, s->cluster_size);
+ offset = qcow2_alloc_clusters(bs, s->cluster_size);
cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
if ((cluster_offset + s->cluster_size) == offset) {
/* we are lucky: contiguous data */
@@ -383,7 +383,7 @@ int64_t alloc_bytes(BlockDriverState *bs, int size)
return offset;
}
-void free_clusters(BlockDriverState *bs,
+void qcow2_free_clusters(BlockDriverState *bs,
int64_t offset, int64_t size)
{
update_refcount(bs, offset, size, -1);
@@ -396,7 +396,7 @@ void free_clusters(BlockDriverState *bs,
*
*/
-void free_any_clusters(BlockDriverState *bs,
+void qcow2_free_any_clusters(BlockDriverState *bs,
uint64_t cluster_offset, int nb_clusters)
{
BDRVQcowState *s = bs->opaque;
@@ -407,12 +407,13 @@ void free_any_clusters(BlockDriverState *bs,
int nb_csectors;
nb_csectors = ((cluster_offset >> s->csize_shift) &
s->csize_mask) + 1;
- free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511,
- nb_csectors * 512);
+ qcow2_free_clusters(bs,
+ (cluster_offset & s->cluster_offset_mask) & ~511,
+ nb_csectors * 512);
return;
}
- free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits);
+ qcow2_free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits);
return;
}
@@ -424,7 +425,8 @@ void free_any_clusters(BlockDriverState *bs,
-void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size)
+void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
+ int64_t size)
{
int refcount;
int64_t start, last, cluster_offset;
@@ -442,17 +444,15 @@ void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size)
}
/* update the refcounts of snapshots and the copied flag */
-int update_snapshot_refcount(BlockDriverState *bs,
- int64_t l1_table_offset,
- int l1_size,
- int addend)
+int qcow2_update_snapshot_refcount(BlockDriverState *bs,
+ int64_t l1_table_offset, int l1_size, int addend)
{
BDRVQcowState *s = bs->opaque;
uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated;
int64_t old_offset, old_l2_offset;
int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount;
- l2_cache_reset(bs);
+ qcow2_l2_cache_reset(bs);
l2_table = NULL;
l1_table = NULL;
@@ -771,7 +771,7 @@ fail:
* Returns 0 if no errors are found, the number of errors in case the image is
* detected as corrupted, and -errno when an internal error occured.
*/
-int check_refcounts(BlockDriverState *bs)
+int qcow2_check_refcounts(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
int64_t size;
diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c
index 2883e50..e1e4d89 100644
--- a/block/qcow2-snapshot.c
+++ b/block/qcow2-snapshot.c
@@ -46,7 +46,7 @@ typedef struct __attribute__((packed)) QCowSnapshotHeader {
/* name follows */
} QCowSnapshotHeader;
-void qcow_free_snapshots(BlockDriverState *bs)
+void qcow2_free_snapshots(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
int i;
@@ -60,7 +60,7 @@ void qcow_free_snapshots(BlockDriverState *bs)
s->nb_snapshots = 0;
}
-int qcow_read_snapshots(BlockDriverState *bs)
+int qcow2_read_snapshots(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
QCowSnapshotHeader h;
@@ -111,7 +111,7 @@ int qcow_read_snapshots(BlockDriverState *bs)
s->snapshots_size = offset - s->snapshots_offset;
return 0;
fail:
- qcow_free_snapshots(bs);
+ qcow2_free_snapshots(bs);
return -1;
}
@@ -137,7 +137,7 @@ static int qcow_write_snapshots(BlockDriverState *bs)
}
snapshots_size = offset;
- snapshots_offset = alloc_clusters(bs, snapshots_size);
+ snapshots_offset = qcow2_alloc_clusters(bs, snapshots_size);
offset = snapshots_offset;
for(i = 0; i < s->nb_snapshots; i++) {
@@ -177,7 +177,7 @@ static int qcow_write_snapshots(BlockDriverState *bs)
goto fail;
/* free the old snapshot table */
- free_clusters(bs, s->snapshots_offset, s->snapshots_size);
+ qcow2_free_clusters(bs, s->snapshots_offset, s->snapshots_size);
s->snapshots_offset = snapshots_offset;
s->snapshots_size = snapshots_size;
return 0;
@@ -229,7 +229,7 @@ static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name)
}
/* if no id is provided, a new one is constructed */
-int qcow_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
+int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
{
BDRVQcowState *s = bs->opaque;
QCowSnapshot *snapshots1, sn1, *sn = &sn1;
@@ -258,12 +258,12 @@ int qcow_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
sn->date_nsec = sn_info->date_nsec;
sn->vm_clock_nsec = sn_info->vm_clock_nsec;
- ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1);
+ ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1);
if (ret < 0)
goto fail;
/* create the L1 table of the snapshot */
- sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
+ sn->l1_table_offset = qcow2_alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
sn->l1_size = s->l1_size;
l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
@@ -298,7 +298,7 @@ int qcow_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
}
/* copy the snapshot 'snapshot_name' into the current disk image */
-int qcow_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
+int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
{
BDRVQcowState *s = bs->opaque;
QCowSnapshot *sn;
@@ -309,10 +309,10 @@ int qcow_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
return -ENOENT;
sn = &s->snapshots[snapshot_index];
- if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0)
+ if (qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0)
goto fail;
- if (grow_l1_table(bs, sn->l1_size) < 0)
+ if (qcow2_grow_l1_table(bs, sn->l1_size) < 0)
goto fail;
s->l1_size = sn->l1_size;
@@ -328,7 +328,7 @@ int qcow_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
be64_to_cpus(&s->l1_table[i]);
}
- if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0)
+ if (qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0)
goto fail;
#ifdef DEBUG_ALLOC
@@ -339,7 +339,7 @@ int qcow_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
return -EIO;
}
-int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
+int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
{
BDRVQcowState *s = bs->opaque;
QCowSnapshot *sn;
@@ -350,14 +350,14 @@ int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
return -ENOENT;
sn = &s->snapshots[snapshot_index];
- ret = update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1);
+ ret = qcow2_update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1);
if (ret < 0)
return ret;
/* must update the copied flag on the current cluster offsets */
- ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
+ ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
if (ret < 0)
return ret;
- free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t));
+ qcow2_free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t));
qemu_free(sn->id_str);
qemu_free(sn->name);
@@ -374,7 +374,7 @@ int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
return 0;
}
-int qcow_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab)
+int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab)
{
BDRVQcowState *s = bs->opaque;
QEMUSnapshotInfo *sn_tab, *sn_info;
diff --git a/block/qcow2.c b/block/qcow2.c
index febdf67..de3edc8 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -227,7 +227,7 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
+ 512);
s->cluster_cache_offset = -1;
- if (refcount_init(bs) < 0)
+ if (qcow2_refcount_init(bs) < 0)
goto fail;
/* read qcow2 extensions */
@@ -247,7 +247,7 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
goto fail;
bs->backing_file[len] = '\0';
}
- if (qcow_read_snapshots(bs) < 0)
+ if (qcow2_read_snapshots(bs) < 0)
goto fail;
#ifdef DEBUG_ALLOC
@@ -256,8 +256,8 @@ static int qcow_open(BlockDriverState *bs, const char *filename, int flags)
return 0;
fail:
- qcow_free_snapshots(bs);
- refcount_close(bs);
+ qcow2_free_snapshots(bs);
+ qcow2_refcount_close(bs);
qemu_free(s->l1_table);
qemu_free(s->l2_cache);
qemu_free(s->cluster_cache);
@@ -314,13 +314,13 @@ static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num,
uint64_t cluster_offset;
*pnum = nb_sectors;
- cluster_offset = get_cluster_offset(bs, sector_num << 9, pnum);
+ cluster_offset = qcow2_get_cluster_offset(bs, sector_num << 9, pnum);
return (cluster_offset != 0);
}
/* handle reading after the end of the backing file */
-int backing_read1(BlockDriverState *bs,
+int qcow2_backing_read1(BlockDriverState *bs,
int64_t sector_num, uint8_t *buf, int nb_sectors)
{
int n1;
@@ -405,7 +405,7 @@ static void qcow_aio_read_cb(void *opaque, int ret)
/* nothing to do */
} else {
if (s->crypt_method) {
- encrypt_sectors(s, acb->sector_num, acb->buf, acb->buf,
+ qcow2_encrypt_sectors(s, acb->sector_num, acb->buf, acb->buf,
acb->n, 0,
&s->aes_decrypt_key);
}
@@ -423,13 +423,14 @@ static void qcow_aio_read_cb(void *opaque, int ret)
/* prepare next AIO request */
acb->n = acb->nb_sectors;
- acb->cluster_offset = get_cluster_offset(bs, acb->sector_num << 9, &acb->n);
+ acb->cluster_offset =
+ qcow2_get_cluster_offset(bs, acb->sector_num << 9, &acb->n);
index_in_cluster = acb->sector_num & (s->cluster_sectors - 1);
if (!acb->cluster_offset) {
if (bs->backing_hd) {
/* read from the base image */
- n1 = backing_read1(bs->backing_hd, acb->sector_num,
+ n1 = qcow2_backing_read1(bs->backing_hd, acb->sector_num,
acb->buf, acb->n);
if (n1 > 0) {
acb->hd_iov.iov_base = (void *)acb->buf;
@@ -454,7 +455,7 @@ static void qcow_aio_read_cb(void *opaque, int ret)
}
} else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) {
/* add AIO support for compressed blocks ? */
- if (decompress_cluster(s, acb->cluster_offset) < 0)
+ if (qcow2_decompress_cluster(s, acb->cluster_offset) < 0)
goto done;
memcpy(acb->buf,
s->cluster_cache + index_in_cluster * 512, 512 * acb->n);
@@ -541,8 +542,8 @@ static void qcow_aio_write_cb(void *opaque, int ret)
if (ret < 0)
goto done;
- if (alloc_cluster_link_l2(bs, acb->cluster_offset, &acb->l2meta) < 0) {
- free_any_clusters(bs, acb->cluster_offset, acb->l2meta.nb_clusters);
+ if (qcow2_alloc_cluster_link_l2(bs, acb->cluster_offset, &acb->l2meta) < 0) {
+ qcow2_free_any_clusters(bs, acb->cluster_offset, acb->l2meta.nb_clusters);
goto done;
}
@@ -562,7 +563,7 @@ static void qcow_aio_write_cb(void *opaque, int ret)
n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors)
n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors;
- acb->cluster_offset = alloc_cluster_offset(bs, acb->sector_num << 9,
+ acb->cluster_offset = qcow2_alloc_cluster_offset(bs, acb->sector_num << 9,
index_in_cluster,
n_end, &acb->n, &acb->l2meta);
if (!acb->cluster_offset || (acb->cluster_offset & 511) != 0) {
@@ -574,7 +575,7 @@ static void qcow_aio_write_cb(void *opaque, int ret)
acb->cluster_data = qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS *
s->cluster_size);
}
- encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf,
+ qcow2_encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf,
acb->n, 1, &s->aes_encrypt_key);
src_buf = acb->cluster_data;
} else {
@@ -623,7 +624,7 @@ static void qcow_close(BlockDriverState *bs)
qemu_free(s->l2_cache);
qemu_free(s->cluster_cache);
qemu_free(s->cluster_data);
- refcount_close(bs);
+ qcow2_refcount_close(bs);
bdrv_delete(s->hd);
}
@@ -733,10 +734,12 @@ static int qcow_create2(const char *filename, int64_t total_size,
s->refcount_block = qemu_mallocz(ref_clusters * s->cluster_size);
/* update refcounts */
- create_refcount_update(s, 0, header_size);
- create_refcount_update(s, s->l1_table_offset, l1_size * sizeof(uint64_t));
- create_refcount_update(s, s->refcount_table_offset, s->cluster_size);
- create_refcount_update(s, s->refcount_block_offset, ref_clusters * s->cluster_size);
+ qcow2_create_refcount_update(s, 0, header_size);
+ qcow2_create_refcount_update(s, s->l1_table_offset,
+ l1_size * sizeof(uint64_t));
+ qcow2_create_refcount_update(s, s->refcount_table_offset, s->cluster_size);
+ qcow2_create_refcount_update(s, s->refcount_block_offset,
+ ref_clusters * s->cluster_size);
/* write all the data */
write(fd, &header, sizeof(header));
@@ -877,8 +880,8 @@ static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
/* could not compress: write normal cluster */
bdrv_write(bs, sector_num, buf, s->cluster_sectors);
} else {
- cluster_offset = alloc_compressed_cluster_offset(bs, sector_num << 9,
- out_len);
+ cluster_offset = qcow2_alloc_compressed_cluster_offset(bs,
+ sector_num << 9, out_len);
if (!cluster_offset)
return -1;
cluster_offset &= s->cluster_offset_mask;
@@ -910,7 +913,7 @@ static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
static int qcow_check(BlockDriverState *bs)
{
- return check_refcounts(bs);
+ return qcow2_check_refcounts(bs);
}
#if 0
@@ -983,10 +986,10 @@ static BlockDriver bdrv_qcow2 = {
.bdrv_aio_writev = qcow_aio_writev,
.bdrv_write_compressed = qcow_write_compressed,
- .bdrv_snapshot_create = qcow_snapshot_create,
- .bdrv_snapshot_goto = qcow_snapshot_goto,
- .bdrv_snapshot_delete = qcow_snapshot_delete,
- .bdrv_snapshot_list = qcow_snapshot_list,
+ .bdrv_snapshot_create = qcow2_snapshot_create,
+ .bdrv_snapshot_goto = qcow2_snapshot_goto,
+ .bdrv_snapshot_delete = qcow2_snapshot_delete,
+ .bdrv_snapshot_list = qcow2_snapshot_list,
.bdrv_get_info = qcow_get_info,
.bdrv_put_buffer = qcow_put_buffer,
diff --git a/block/qcow2.h b/block/qcow2.h
index 397f21d..d734003 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -148,56 +148,56 @@ static inline int64_t align_offset(int64_t offset, int n)
// FIXME Need qcow2_ prefix to global functions
/* qcow2.c functions */
-void l2_cache_reset(BlockDriverState *bs);
-int backing_read1(BlockDriverState *bs,
+int qcow2_backing_read1(BlockDriverState *bs,
int64_t sector_num, uint8_t *buf, int nb_sectors);
/* qcow2-refcount.c functions */
-int refcount_init(BlockDriverState *bs);
-void refcount_close(BlockDriverState *bs);
+int qcow2_refcount_init(BlockDriverState *bs);
+void qcow2_refcount_close(BlockDriverState *bs);
-int64_t alloc_clusters(BlockDriverState *bs, int64_t size);
-int64_t alloc_bytes(BlockDriverState *bs, int size);
-void free_clusters(BlockDriverState *bs,
+int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size);
+int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
+void qcow2_free_clusters(BlockDriverState *bs,
int64_t offset, int64_t size);
-void free_any_clusters(BlockDriverState *bs,
+void qcow2_free_any_clusters(BlockDriverState *bs,
uint64_t cluster_offset, int nb_clusters);
-void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size);
-int update_snapshot_refcount(BlockDriverState *bs,
- int64_t l1_table_offset,
- int l1_size,
- int addend);
+void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
+ int64_t size);
+int qcow2_update_snapshot_refcount(BlockDriverState *bs,
+ int64_t l1_table_offset, int l1_size, int addend);
-int check_refcounts(BlockDriverState *bs);
+int qcow2_check_refcounts(BlockDriverState *bs);
/* qcow2-cluster.c functions */
-int grow_l1_table(BlockDriverState *bs, int min_size);
-int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
-void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+int qcow2_grow_l1_table(BlockDriverState *bs, int min_size);
+void qcow2_l2_cache_reset(BlockDriverState *bs);
+int qcow2_decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
+void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
uint8_t *out_buf, const uint8_t *in_buf,
int nb_sectors, int enc,
const AES_KEY *key);
-uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int *num);
-uint64_t alloc_cluster_offset(BlockDriverState *bs,
+uint64_t qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
+ int *num);
+uint64_t qcow2_alloc_cluster_offset(BlockDriverState *bs,
uint64_t offset,
int n_start, int n_end,
int *num, QCowL2Meta *m);
-uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
+uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
uint64_t offset,
int compressed_size);
-int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
+int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
QCowL2Meta *m);
/* qcow2-snapshot.c functions */
-int qcow_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
-int qcow_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
-int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
-int qcow_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
+int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
+int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
+int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
+int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
-void qcow_free_snapshots(BlockDriverState *bs);
-int qcow_read_snapshots(BlockDriverState *bs);
+void qcow2_free_snapshots(BlockDriverState *bs);
+int qcow2_read_snapshots(BlockDriverState *bs);
#endif
--
1.6.0.6
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [Qemu-devel] [PATCH 0/4] Split qcow2 driver
2009-05-28 14:07 [Qemu-devel] [PATCH 0/4] Split qcow2 driver Kevin Wolf
` (3 preceding siblings ...)
2009-05-28 14:07 ` [Qemu-devel] [PATCH 4/4] qcow2: Rename global functions Kevin Wolf
@ 2009-05-28 14:39 ` Anthony Liguori
2009-05-28 14:56 ` Kevin Wolf
2009-05-28 15:11 ` Mark McLoughlin
4 siblings, 2 replies; 9+ messages in thread
From: Anthony Liguori @ 2009-05-28 14:39 UTC (permalink / raw)
To: Kevin Wolf; +Cc: Mark McLoughlin, qemu-devel
Kevin Wolf wrote:
> The current qcow2 code is a monster of 3000 lines of code. This is hardly
> manageable and doesn't exactly improve the driver's structure.
>
> This patch series tries to split the driver in smaller modules. It doesn't
> contain changes to functionality or structure, especially the latter might come
> later as this series makes it much clearer what the internal interfaces used by
> the qcow2 driver actually are.
>
> The first three patches mainly move code around. They also build up a qcow2.h
> header file which contains the common structs and functions used by several
> modules. Some functions need to become global to keep things compilable.
>
> The fourth patch cleans up the global namespace by adding a qcow2_ prefix to
> all of the new global functions introduced by the first patches.
>
> Kevin Wolf (4):
> qcow2: Split out refcount handling
> qcow2: Split out guest cluster functions
> qcow2: Split out snapshot functions
> qcow2: Rename global functions
>
Could you introduce a new qcow2 directory? Perhaps add a README too
that we can use to start trying to store some information about how the
qcow2 driver works to help other people dive into it.
I think markmc had started a document at one point, right?
> Makefile | 4 +-
> block/qcow2-cluster.c | 755 ++++++++++++++++++
> block/qcow2-refcount.c | 836 +++++++++++++++++++
> block/qcow2-snapshot.c | 405 ++++++++++
> block/qcow2.c | 2081 +-----------------------------------------------
> block/qcow2.h | 203 +++++
> 6 files changed, 2233 insertions(+), 2051 deletions(-)
> create mode 100644 block/qcow2-cluster.c
> create mode 100644 block/qcow2-refcount.c
> create mode 100644 block/qcow2-snapshot.c
> create mode 100644 block/qcow2.h
>
>
>
>
Regards,
Anthony Liguori
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [Qemu-devel] [PATCH 0/4] Split qcow2 driver
2009-05-28 14:39 ` [Qemu-devel] [PATCH 0/4] Split qcow2 driver Anthony Liguori
@ 2009-05-28 14:56 ` Kevin Wolf
2009-05-28 15:18 ` Anthony Liguori
2009-05-28 15:11 ` Mark McLoughlin
1 sibling, 1 reply; 9+ messages in thread
From: Kevin Wolf @ 2009-05-28 14:56 UTC (permalink / raw)
To: Anthony Liguori; +Cc: Mark McLoughlin, qemu-devel
Anthony Liguori schrieb:
> Kevin Wolf wrote:
>> The current qcow2 code is a monster of 3000 lines of code. This is hardly
>> manageable and doesn't exactly improve the driver's structure.
>>
>> This patch series tries to split the driver in smaller modules. It doesn't
>> contain changes to functionality or structure, especially the latter might come
>> later as this series makes it much clearer what the internal interfaces used by
>> the qcow2 driver actually are.
>>
>> The first three patches mainly move code around. They also build up a qcow2.h
>> header file which contains the common structs and functions used by several
>> modules. Some functions need to become global to keep things compilable.
>>
>> The fourth patch cleans up the global namespace by adding a qcow2_ prefix to
>> all of the new global functions introduced by the first patches.
>>
>> Kevin Wolf (4):
>> qcow2: Split out refcount handling
>> qcow2: Split out guest cluster functions
>> qcow2: Split out snapshot functions
>> qcow2: Rename global functions
>>
>
> Could you introduce a new qcow2 directory?
I certainly could, but don't you think this is a bit too much? I mean,
block/ isn't really crowded and if we end up having a separate directory
for each file I wouldn't call this a good directory structure either.
Maybe we should wait for a few other opinions and then decide if a new
directory is the way to go or not.
> Perhaps add a README too
> that we can use to start trying to store some information about how the
> qcow2 driver works to help other people dive into it.
That would obviously be a different patch, but in general documentation
certainly wouldn't hurt. The very first thing to document would be the
image format itself, before even starting with the driver.
Kevin
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Qemu-devel] [PATCH 0/4] Split qcow2 driver
2009-05-28 14:56 ` Kevin Wolf
@ 2009-05-28 15:18 ` Anthony Liguori
0 siblings, 0 replies; 9+ messages in thread
From: Anthony Liguori @ 2009-05-28 15:18 UTC (permalink / raw)
To: Kevin Wolf; +Cc: Mark McLoughlin, qemu-devel
Kevin Wolf wrote:
> Anthony Liguori schrieb:
>
>> Could you introduce a new qcow2 directory?
>>
>
> I certainly could, but don't you think this is a bit too much? I mean,
> block/ isn't really crowded and if we end up having a separate directory
> for each file I wouldn't call this a good directory structure either.
>
> Maybe we should wait for a few other opinions and then decide if a new
> directory is the way to go or not.
>
Not a blocker since renaming is reasonable enough in git. Just thought
it was worth bringing up since we're talking about reorganizing code for
better maintainability...
>> Perhaps add a README too
>> that we can use to start trying to store some information about how the
>> qcow2 driver works to help other people dive into it.
>>
>
> That would obviously be a different patch, but in general documentation
> certainly wouldn't hurt. The very first thing to document would be the
> image format itself, before even starting with the driver.
>
Regards,
Anthony Liguori
> Kevin
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Qemu-devel] [PATCH 0/4] Split qcow2 driver
2009-05-28 14:39 ` [Qemu-devel] [PATCH 0/4] Split qcow2 driver Anthony Liguori
2009-05-28 14:56 ` Kevin Wolf
@ 2009-05-28 15:11 ` Mark McLoughlin
1 sibling, 0 replies; 9+ messages in thread
From: Mark McLoughlin @ 2009-05-28 15:11 UTC (permalink / raw)
To: Anthony Liguori; +Cc: Kevin Wolf, qemu-devel
On Thu, 2009-05-28 at 09:39 -0500, Anthony Liguori wrote:
> Could you introduce a new qcow2 directory? Perhaps add a README too
> that we can use to start trying to store some information about how the
> qcow2 driver works to help other people dive into it.
>
> I think markmc had started a document at one point, right?
Here it is:
http://www.gnome.org/~markmc/qcow-image-format.html
Cheers,
Mark.
^ permalink raw reply [flat|nested] 9+ messages in thread