root / block / qcow2-refcount.c @ edcdd562
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/*
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* Block driver for the QCOW version 2 format
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*
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* Copyright (c) 2004-2006 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h" |
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#include "block_int.h" |
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#include "block/qcow2.h" |
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|
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static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size);
|
30 |
static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, |
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int64_t offset, int64_t length, |
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int addend);
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|
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|
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static int cache_refcount_updates = 0; |
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|
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static int write_refcount_block(BlockDriverState *bs) |
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{ |
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BDRVQcowState *s = bs->opaque; |
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size_t size = s->cluster_size; |
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|
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if (s->refcount_block_cache_offset == 0) { |
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return 0; |
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} |
45 |
|
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BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE); |
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if (bdrv_pwrite_sync(bs->file, s->refcount_block_cache_offset,
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s->refcount_block_cache, size) < 0)
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{ |
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return -EIO;
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} |
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return 0; |
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} |
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|
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/*********************************************************/
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/* refcount handling */
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|
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int qcow2_refcount_init(BlockDriverState *bs)
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{ |
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BDRVQcowState *s = bs->opaque; |
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int ret, refcount_table_size2, i;
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|
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s->refcount_block_cache = qemu_malloc(s->cluster_size); |
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refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
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s->refcount_table = qemu_malloc(refcount_table_size2); |
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if (s->refcount_table_size > 0) { |
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BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD); |
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ret = bdrv_pread(bs->file, s->refcount_table_offset, |
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s->refcount_table, refcount_table_size2); |
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if (ret != refcount_table_size2)
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goto fail;
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for(i = 0; i < s->refcount_table_size; i++) |
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be64_to_cpus(&s->refcount_table[i]); |
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} |
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return 0; |
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fail:
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return -ENOMEM;
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} |
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|
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void qcow2_refcount_close(BlockDriverState *bs)
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{ |
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BDRVQcowState *s = bs->opaque; |
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qemu_free(s->refcount_block_cache); |
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qemu_free(s->refcount_table); |
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} |
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|
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|
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static int load_refcount_block(BlockDriverState *bs, |
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int64_t refcount_block_offset) |
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{ |
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BDRVQcowState *s = bs->opaque; |
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int ret;
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|
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if (cache_refcount_updates) {
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ret = write_refcount_block(bs); |
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if (ret < 0) { |
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return ret;
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} |
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} |
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|
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BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_LOAD); |
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ret = bdrv_pread(bs->file, refcount_block_offset, s->refcount_block_cache, |
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s->cluster_size); |
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if (ret < 0) { |
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s->refcount_block_cache_offset = 0;
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return ret;
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} |
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s->refcount_block_cache_offset = refcount_block_offset; |
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return 0; |
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} |
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|
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/*
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* Returns the refcount of the cluster given by its index. Any non-negative
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* return value is the refcount of the cluster, negative values are -errno
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* and indicate an error.
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*/
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static int get_refcount(BlockDriverState *bs, int64_t cluster_index) |
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{ |
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BDRVQcowState *s = bs->opaque; |
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int refcount_table_index, block_index;
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int64_t refcount_block_offset; |
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int ret;
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|
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refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
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if (refcount_table_index >= s->refcount_table_size)
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return 0; |
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refcount_block_offset = s->refcount_table[refcount_table_index]; |
130 |
if (!refcount_block_offset)
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return 0; |
132 |
if (refcount_block_offset != s->refcount_block_cache_offset) {
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/* better than nothing: return allocated if read error */
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ret = load_refcount_block(bs, refcount_block_offset); |
135 |
if (ret < 0) { |
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return ret;
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} |
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} |
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block_index = cluster_index & |
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((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
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return be16_to_cpu(s->refcount_block_cache[block_index]);
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} |
143 |
|
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/*
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* Rounds the refcount table size up to avoid growing the table for each single
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* refcount block that is allocated.
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*/
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static unsigned int next_refcount_table_size(BDRVQcowState *s, |
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unsigned int min_size) |
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{ |
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unsigned int min_clusters = (min_size >> (s->cluster_bits - 3)) + 1; |
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unsigned int refcount_table_clusters = |
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MAX(1, s->refcount_table_size >> (s->cluster_bits - 3)); |
154 |
|
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while (min_clusters > refcount_table_clusters) {
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refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2; |
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} |
158 |
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return refcount_table_clusters << (s->cluster_bits - 3); |
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} |
161 |
|
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|
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/* Checks if two offsets are described by the same refcount block */
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static int in_same_refcount_block(BDRVQcowState *s, uint64_t offset_a, |
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uint64_t offset_b) |
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{ |
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uint64_t block_a = offset_a >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
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uint64_t block_b = offset_b >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
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return (block_a == block_b);
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} |
172 |
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/*
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* Loads a refcount block. If it doesn't exist yet, it is allocated first
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* (including growing the refcount table if needed).
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*
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* Returns the offset of the refcount block on success or -errno in error case
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*/
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static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
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{ |
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BDRVQcowState *s = bs->opaque; |
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unsigned int refcount_table_index; |
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int ret;
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BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC); |
186 |
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/* Find the refcount block for the given cluster */
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refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
189 |
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if (refcount_table_index < s->refcount_table_size) {
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191 |
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uint64_t refcount_block_offset = |
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s->refcount_table[refcount_table_index]; |
194 |
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/* If it's already there, we're done */
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if (refcount_block_offset) {
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if (refcount_block_offset != s->refcount_block_cache_offset) {
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ret = load_refcount_block(bs, refcount_block_offset); |
199 |
if (ret < 0) { |
200 |
return ret;
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201 |
} |
202 |
} |
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return refcount_block_offset;
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} |
205 |
} |
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/*
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* If we came here, we need to allocate something. Something is at least
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* a cluster for the new refcount block. It may also include a new refcount
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* table if the old refcount table is too small.
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*
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* Note that allocating clusters here needs some special care:
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*
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* - We can't use the normal qcow2_alloc_clusters(), it would try to
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* increase the refcount and very likely we would end up with an endless
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* recursion. Instead we must place the refcount blocks in a way that
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* they can describe them themselves.
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*
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* - We need to consider that at this point we are inside update_refcounts
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* and doing the initial refcount increase. This means that some clusters
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* have already been allocated by the caller, but their refcount isn't
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* accurate yet. free_cluster_index tells us where this allocation ends
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* as long as we don't overwrite it by freeing clusters.
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*
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* - alloc_clusters_noref and qcow2_free_clusters may load a different
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* refcount block into the cache
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*/
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|
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if (cache_refcount_updates) {
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ret = write_refcount_block(bs); |
231 |
if (ret < 0) { |
232 |
return ret;
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} |
234 |
} |
235 |
|
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/* Allocate the refcount block itself and mark it as used */
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int64_t new_block = alloc_clusters_noref(bs, s->cluster_size); |
238 |
if (new_block < 0) { |
239 |
return new_block;
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} |
241 |
|
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#ifdef DEBUG_ALLOC2
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fprintf(stderr, "qcow2: Allocate refcount block %d for %" PRIx64
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" at %" PRIx64 "\n", |
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refcount_table_index, cluster_index << s->cluster_bits, new_block); |
246 |
#endif
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247 |
|
248 |
if (in_same_refcount_block(s, new_block, cluster_index << s->cluster_bits)) {
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/* Zero the new refcount block before updating it */
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250 |
memset(s->refcount_block_cache, 0, s->cluster_size);
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s->refcount_block_cache_offset = new_block; |
252 |
|
253 |
/* The block describes itself, need to update the cache */
|
254 |
int block_index = (new_block >> s->cluster_bits) &
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((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
256 |
s->refcount_block_cache[block_index] = cpu_to_be16(1);
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257 |
} else {
|
258 |
/* Described somewhere else. This can recurse at most twice before we
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259 |
* arrive at a block that describes itself. */
|
260 |
ret = update_refcount(bs, new_block, s->cluster_size, 1);
|
261 |
if (ret < 0) { |
262 |
goto fail_block;
|
263 |
} |
264 |
|
265 |
bdrv_flush(bs->file); |
266 |
|
267 |
/* Initialize the new refcount block only after updating its refcount,
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268 |
* update_refcount uses the refcount cache itself */
|
269 |
memset(s->refcount_block_cache, 0, s->cluster_size);
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270 |
s->refcount_block_cache_offset = new_block; |
271 |
} |
272 |
|
273 |
/* Now the new refcount block needs to be written to disk */
|
274 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE); |
275 |
ret = bdrv_pwrite_sync(bs->file, new_block, s->refcount_block_cache, |
276 |
s->cluster_size); |
277 |
if (ret < 0) { |
278 |
goto fail_block;
|
279 |
} |
280 |
|
281 |
/* If the refcount table is big enough, just hook the block up there */
|
282 |
if (refcount_table_index < s->refcount_table_size) {
|
283 |
uint64_t data64 = cpu_to_be64(new_block); |
284 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP); |
285 |
ret = bdrv_pwrite_sync(bs->file, |
286 |
s->refcount_table_offset + refcount_table_index * sizeof(uint64_t),
|
287 |
&data64, sizeof(data64));
|
288 |
if (ret < 0) { |
289 |
goto fail_block;
|
290 |
} |
291 |
|
292 |
s->refcount_table[refcount_table_index] = new_block; |
293 |
return new_block;
|
294 |
} |
295 |
|
296 |
/*
|
297 |
* If we come here, we need to grow the refcount table. Again, a new
|
298 |
* refcount table needs some space and we can't simply allocate to avoid
|
299 |
* endless recursion.
|
300 |
*
|
301 |
* Therefore let's grab new refcount blocks at the end of the image, which
|
302 |
* will describe themselves and the new refcount table. This way we can
|
303 |
* reference them only in the new table and do the switch to the new
|
304 |
* refcount table at once without producing an inconsistent state in
|
305 |
* between.
|
306 |
*/
|
307 |
BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_GROW); |
308 |
|
309 |
/* Calculate the number of refcount blocks needed so far */
|
310 |
uint64_t refcount_block_clusters = 1 << (s->cluster_bits - REFCOUNT_SHIFT);
|
311 |
uint64_t blocks_used = (s->free_cluster_index + |
312 |
refcount_block_clusters - 1) / refcount_block_clusters;
|
313 |
|
314 |
/* And now we need at least one block more for the new metadata */
|
315 |
uint64_t table_size = next_refcount_table_size(s, blocks_used + 1);
|
316 |
uint64_t last_table_size; |
317 |
uint64_t blocks_clusters; |
318 |
do {
|
319 |
uint64_t table_clusters = size_to_clusters(s, table_size); |
320 |
blocks_clusters = 1 +
|
321 |
((table_clusters + refcount_block_clusters - 1)
|
322 |
/ refcount_block_clusters); |
323 |
uint64_t meta_clusters = table_clusters + blocks_clusters; |
324 |
|
325 |
last_table_size = table_size; |
326 |
table_size = next_refcount_table_size(s, blocks_used + |
327 |
((meta_clusters + refcount_block_clusters - 1)
|
328 |
/ refcount_block_clusters)); |
329 |
|
330 |
} while (last_table_size != table_size);
|
331 |
|
332 |
#ifdef DEBUG_ALLOC2
|
333 |
fprintf(stderr, "qcow2: Grow refcount table %" PRId32 " => %" PRId64 "\n", |
334 |
s->refcount_table_size, table_size); |
335 |
#endif
|
336 |
|
337 |
/* Create the new refcount table and blocks */
|
338 |
uint64_t meta_offset = (blocks_used * refcount_block_clusters) * |
339 |
s->cluster_size; |
340 |
uint64_t table_offset = meta_offset + blocks_clusters * s->cluster_size; |
341 |
uint16_t *new_blocks = qemu_mallocz(blocks_clusters * s->cluster_size); |
342 |
uint64_t *new_table = qemu_mallocz(table_size * sizeof(uint64_t));
|
343 |
|
344 |
assert(meta_offset >= (s->free_cluster_index * s->cluster_size)); |
345 |
|
346 |
/* Fill the new refcount table */
|
347 |
memcpy(new_table, s->refcount_table, |
348 |
s->refcount_table_size * sizeof(uint64_t));
|
349 |
new_table[refcount_table_index] = new_block; |
350 |
|
351 |
int i;
|
352 |
for (i = 0; i < blocks_clusters; i++) { |
353 |
new_table[blocks_used + i] = meta_offset + (i * s->cluster_size); |
354 |
} |
355 |
|
356 |
/* Fill the refcount blocks */
|
357 |
uint64_t table_clusters = size_to_clusters(s, table_size * sizeof(uint64_t));
|
358 |
int block = 0; |
359 |
for (i = 0; i < table_clusters + blocks_clusters; i++) { |
360 |
new_blocks[block++] = cpu_to_be16(1);
|
361 |
} |
362 |
|
363 |
/* Write refcount blocks to disk */
|
364 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS); |
365 |
ret = bdrv_pwrite_sync(bs->file, meta_offset, new_blocks, |
366 |
blocks_clusters * s->cluster_size); |
367 |
qemu_free(new_blocks); |
368 |
if (ret < 0) { |
369 |
goto fail_table;
|
370 |
} |
371 |
|
372 |
/* Write refcount table to disk */
|
373 |
for(i = 0; i < table_size; i++) { |
374 |
cpu_to_be64s(&new_table[i]); |
375 |
} |
376 |
|
377 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE); |
378 |
ret = bdrv_pwrite_sync(bs->file, table_offset, new_table, |
379 |
table_size * sizeof(uint64_t));
|
380 |
if (ret < 0) { |
381 |
goto fail_table;
|
382 |
} |
383 |
|
384 |
for(i = 0; i < table_size; i++) { |
385 |
cpu_to_be64s(&new_table[i]); |
386 |
} |
387 |
|
388 |
/* Hook up the new refcount table in the qcow2 header */
|
389 |
uint8_t data[12];
|
390 |
cpu_to_be64w((uint64_t*)data, table_offset); |
391 |
cpu_to_be32w((uint32_t*)(data + 8), table_clusters);
|
392 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE); |
393 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, refcount_table_offset), |
394 |
data, sizeof(data));
|
395 |
if (ret < 0) { |
396 |
goto fail_table;
|
397 |
} |
398 |
|
399 |
/* And switch it in memory */
|
400 |
uint64_t old_table_offset = s->refcount_table_offset; |
401 |
uint64_t old_table_size = s->refcount_table_size; |
402 |
|
403 |
qemu_free(s->refcount_table); |
404 |
s->refcount_table = new_table; |
405 |
s->refcount_table_size = table_size; |
406 |
s->refcount_table_offset = table_offset; |
407 |
|
408 |
/* Free old table. Remember, we must not change free_cluster_index */
|
409 |
uint64_t old_free_cluster_index = s->free_cluster_index; |
410 |
qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
|
411 |
s->free_cluster_index = old_free_cluster_index; |
412 |
|
413 |
ret = load_refcount_block(bs, new_block); |
414 |
if (ret < 0) { |
415 |
goto fail_block;
|
416 |
} |
417 |
|
418 |
return new_block;
|
419 |
|
420 |
fail_table:
|
421 |
qemu_free(new_table); |
422 |
fail_block:
|
423 |
s->refcount_block_cache_offset = 0;
|
424 |
return ret;
|
425 |
} |
426 |
|
427 |
#define REFCOUNTS_PER_SECTOR (512 >> REFCOUNT_SHIFT) |
428 |
static int write_refcount_block_entries(BlockDriverState *bs, |
429 |
int64_t refcount_block_offset, int first_index, int last_index) |
430 |
{ |
431 |
BDRVQcowState *s = bs->opaque; |
432 |
size_t size; |
433 |
int ret;
|
434 |
|
435 |
if (cache_refcount_updates) {
|
436 |
return 0; |
437 |
} |
438 |
|
439 |
if (first_index < 0) { |
440 |
return 0; |
441 |
} |
442 |
|
443 |
first_index &= ~(REFCOUNTS_PER_SECTOR - 1);
|
444 |
last_index = (last_index + REFCOUNTS_PER_SECTOR) |
445 |
& ~(REFCOUNTS_PER_SECTOR - 1);
|
446 |
|
447 |
size = (last_index - first_index) << REFCOUNT_SHIFT; |
448 |
|
449 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE_PART); |
450 |
ret = bdrv_pwrite(bs->file, |
451 |
refcount_block_offset + (first_index << REFCOUNT_SHIFT), |
452 |
&s->refcount_block_cache[first_index], size); |
453 |
if (ret < 0) { |
454 |
return ret;
|
455 |
} |
456 |
|
457 |
return 0; |
458 |
} |
459 |
|
460 |
/* XXX: cache several refcount block clusters ? */
|
461 |
static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, |
462 |
int64_t offset, int64_t length, int addend)
|
463 |
{ |
464 |
BDRVQcowState *s = bs->opaque; |
465 |
int64_t start, last, cluster_offset; |
466 |
int64_t refcount_block_offset = 0;
|
467 |
int64_t table_index = -1, old_table_index;
|
468 |
int first_index = -1, last_index = -1; |
469 |
int ret;
|
470 |
|
471 |
#ifdef DEBUG_ALLOC2
|
472 |
printf("update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n", |
473 |
offset, length, addend); |
474 |
#endif
|
475 |
if (length < 0) { |
476 |
return -EINVAL;
|
477 |
} else if (length == 0) { |
478 |
return 0; |
479 |
} |
480 |
|
481 |
start = offset & ~(s->cluster_size - 1);
|
482 |
last = (offset + length - 1) & ~(s->cluster_size - 1); |
483 |
for(cluster_offset = start; cluster_offset <= last;
|
484 |
cluster_offset += s->cluster_size) |
485 |
{ |
486 |
int block_index, refcount;
|
487 |
int64_t cluster_index = cluster_offset >> s->cluster_bits; |
488 |
int64_t new_block; |
489 |
|
490 |
/* Only write refcount block to disk when we are done with it */
|
491 |
old_table_index = table_index; |
492 |
table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
493 |
if ((old_table_index >= 0) && (table_index != old_table_index)) { |
494 |
|
495 |
ret = write_refcount_block_entries(bs, refcount_block_offset, |
496 |
first_index, last_index); |
497 |
if (ret < 0) { |
498 |
return ret;
|
499 |
} |
500 |
|
501 |
first_index = -1;
|
502 |
last_index = -1;
|
503 |
} |
504 |
|
505 |
/* Load the refcount block and allocate it if needed */
|
506 |
new_block = alloc_refcount_block(bs, cluster_index); |
507 |
if (new_block < 0) { |
508 |
ret = new_block; |
509 |
goto fail;
|
510 |
} |
511 |
refcount_block_offset = new_block; |
512 |
|
513 |
/* we can update the count and save it */
|
514 |
block_index = cluster_index & |
515 |
((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
516 |
if (first_index == -1 || block_index < first_index) { |
517 |
first_index = block_index; |
518 |
} |
519 |
if (block_index > last_index) {
|
520 |
last_index = block_index; |
521 |
} |
522 |
|
523 |
refcount = be16_to_cpu(s->refcount_block_cache[block_index]); |
524 |
refcount += addend; |
525 |
if (refcount < 0 || refcount > 0xffff) { |
526 |
ret = -EINVAL; |
527 |
goto fail;
|
528 |
} |
529 |
if (refcount == 0 && cluster_index < s->free_cluster_index) { |
530 |
s->free_cluster_index = cluster_index; |
531 |
} |
532 |
s->refcount_block_cache[block_index] = cpu_to_be16(refcount); |
533 |
} |
534 |
|
535 |
ret = 0;
|
536 |
fail:
|
537 |
|
538 |
/* Write last changed block to disk */
|
539 |
if (refcount_block_offset != 0) { |
540 |
int wret;
|
541 |
wret = write_refcount_block_entries(bs, refcount_block_offset, |
542 |
first_index, last_index); |
543 |
if (wret < 0) { |
544 |
return ret < 0 ? ret : wret; |
545 |
} |
546 |
} |
547 |
|
548 |
/*
|
549 |
* Try do undo any updates if an error is returned (This may succeed in
|
550 |
* some cases like ENOSPC for allocating a new refcount block)
|
551 |
*/
|
552 |
if (ret < 0) { |
553 |
int dummy;
|
554 |
dummy = update_refcount(bs, offset, cluster_offset - offset, -addend); |
555 |
(void)dummy;
|
556 |
} |
557 |
|
558 |
return ret;
|
559 |
} |
560 |
|
561 |
/*
|
562 |
* Increases or decreases the refcount of a given cluster by one.
|
563 |
* addend must be 1 or -1.
|
564 |
*
|
565 |
* If the return value is non-negative, it is the new refcount of the cluster.
|
566 |
* If it is negative, it is -errno and indicates an error.
|
567 |
*/
|
568 |
static int update_cluster_refcount(BlockDriverState *bs, |
569 |
int64_t cluster_index, |
570 |
int addend)
|
571 |
{ |
572 |
BDRVQcowState *s = bs->opaque; |
573 |
int ret;
|
574 |
|
575 |
ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
|
576 |
if (ret < 0) { |
577 |
return ret;
|
578 |
} |
579 |
|
580 |
bdrv_flush(bs->file); |
581 |
|
582 |
return get_refcount(bs, cluster_index);
|
583 |
} |
584 |
|
585 |
|
586 |
|
587 |
/*********************************************************/
|
588 |
/* cluster allocation functions */
|
589 |
|
590 |
|
591 |
|
592 |
/* return < 0 if error */
|
593 |
static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
|
594 |
{ |
595 |
BDRVQcowState *s = bs->opaque; |
596 |
int i, nb_clusters, refcount;
|
597 |
|
598 |
nb_clusters = size_to_clusters(s, size); |
599 |
retry:
|
600 |
for(i = 0; i < nb_clusters; i++) { |
601 |
int64_t next_cluster_index = s->free_cluster_index++; |
602 |
refcount = get_refcount(bs, next_cluster_index); |
603 |
|
604 |
if (refcount < 0) { |
605 |
return refcount;
|
606 |
} else if (refcount != 0) { |
607 |
goto retry;
|
608 |
} |
609 |
} |
610 |
#ifdef DEBUG_ALLOC2
|
611 |
printf("alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n", |
612 |
size, |
613 |
(s->free_cluster_index - nb_clusters) << s->cluster_bits); |
614 |
#endif
|
615 |
return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
|
616 |
} |
617 |
|
618 |
int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size) |
619 |
{ |
620 |
int64_t offset; |
621 |
int ret;
|
622 |
|
623 |
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC); |
624 |
offset = alloc_clusters_noref(bs, size); |
625 |
if (offset < 0) { |
626 |
return offset;
|
627 |
} |
628 |
|
629 |
ret = update_refcount(bs, offset, size, 1);
|
630 |
if (ret < 0) { |
631 |
return ret;
|
632 |
} |
633 |
|
634 |
return offset;
|
635 |
} |
636 |
|
637 |
/* only used to allocate compressed sectors. We try to allocate
|
638 |
contiguous sectors. size must be <= cluster_size */
|
639 |
int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
|
640 |
{ |
641 |
BDRVQcowState *s = bs->opaque; |
642 |
int64_t offset, cluster_offset; |
643 |
int free_in_cluster;
|
644 |
|
645 |
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_BYTES); |
646 |
assert(size > 0 && size <= s->cluster_size);
|
647 |
if (s->free_byte_offset == 0) { |
648 |
s->free_byte_offset = qcow2_alloc_clusters(bs, s->cluster_size); |
649 |
if (s->free_byte_offset < 0) { |
650 |
return s->free_byte_offset;
|
651 |
} |
652 |
} |
653 |
redo:
|
654 |
free_in_cluster = s->cluster_size - |
655 |
(s->free_byte_offset & (s->cluster_size - 1));
|
656 |
if (size <= free_in_cluster) {
|
657 |
/* enough space in current cluster */
|
658 |
offset = s->free_byte_offset; |
659 |
s->free_byte_offset += size; |
660 |
free_in_cluster -= size; |
661 |
if (free_in_cluster == 0) |
662 |
s->free_byte_offset = 0;
|
663 |
if ((offset & (s->cluster_size - 1)) != 0) |
664 |
update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
665 |
} else {
|
666 |
offset = qcow2_alloc_clusters(bs, s->cluster_size); |
667 |
if (offset < 0) { |
668 |
return offset;
|
669 |
} |
670 |
cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
|
671 |
if ((cluster_offset + s->cluster_size) == offset) {
|
672 |
/* we are lucky: contiguous data */
|
673 |
offset = s->free_byte_offset; |
674 |
update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
675 |
s->free_byte_offset += size; |
676 |
} else {
|
677 |
s->free_byte_offset = offset; |
678 |
goto redo;
|
679 |
} |
680 |
} |
681 |
|
682 |
bdrv_flush(bs->file); |
683 |
return offset;
|
684 |
} |
685 |
|
686 |
void qcow2_free_clusters(BlockDriverState *bs,
|
687 |
int64_t offset, int64_t size) |
688 |
{ |
689 |
int ret;
|
690 |
|
691 |
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE); |
692 |
ret = update_refcount(bs, offset, size, -1);
|
693 |
if (ret < 0) { |
694 |
fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
|
695 |
/* TODO Remember the clusters to free them later and avoid leaking */
|
696 |
} |
697 |
} |
698 |
|
699 |
/*
|
700 |
* free_any_clusters
|
701 |
*
|
702 |
* free clusters according to its type: compressed or not
|
703 |
*
|
704 |
*/
|
705 |
|
706 |
void qcow2_free_any_clusters(BlockDriverState *bs,
|
707 |
uint64_t cluster_offset, int nb_clusters)
|
708 |
{ |
709 |
BDRVQcowState *s = bs->opaque; |
710 |
|
711 |
/* free the cluster */
|
712 |
|
713 |
if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
|
714 |
int nb_csectors;
|
715 |
nb_csectors = ((cluster_offset >> s->csize_shift) & |
716 |
s->csize_mask) + 1;
|
717 |
qcow2_free_clusters(bs, |
718 |
(cluster_offset & s->cluster_offset_mask) & ~511,
|
719 |
nb_csectors * 512);
|
720 |
return;
|
721 |
} |
722 |
|
723 |
qcow2_free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits); |
724 |
|
725 |
return;
|
726 |
} |
727 |
|
728 |
|
729 |
|
730 |
/*********************************************************/
|
731 |
/* snapshots and image creation */
|
732 |
|
733 |
|
734 |
|
735 |
void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
|
736 |
int64_t size) |
737 |
{ |
738 |
int refcount;
|
739 |
int64_t start, last, cluster_offset; |
740 |
uint16_t *p; |
741 |
|
742 |
start = offset & ~(s->cluster_size - 1);
|
743 |
last = (offset + size - 1) & ~(s->cluster_size - 1); |
744 |
for(cluster_offset = start; cluster_offset <= last;
|
745 |
cluster_offset += s->cluster_size) { |
746 |
p = &s->refcount_block[cluster_offset >> s->cluster_bits]; |
747 |
refcount = be16_to_cpu(*p); |
748 |
refcount++; |
749 |
*p = cpu_to_be16(refcount); |
750 |
} |
751 |
} |
752 |
|
753 |
/* update the refcounts of snapshots and the copied flag */
|
754 |
int qcow2_update_snapshot_refcount(BlockDriverState *bs,
|
755 |
int64_t l1_table_offset, int l1_size, int addend) |
756 |
{ |
757 |
BDRVQcowState *s = bs->opaque; |
758 |
uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; |
759 |
int64_t old_offset, old_l2_offset; |
760 |
int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount;
|
761 |
|
762 |
qcow2_l2_cache_reset(bs); |
763 |
cache_refcount_updates = 1;
|
764 |
|
765 |
l2_table = NULL;
|
766 |
l1_table = NULL;
|
767 |
l1_size2 = l1_size * sizeof(uint64_t);
|
768 |
if (l1_table_offset != s->l1_table_offset) {
|
769 |
if (l1_size2 != 0) { |
770 |
l1_table = qemu_mallocz(align_offset(l1_size2, 512));
|
771 |
} else {
|
772 |
l1_table = NULL;
|
773 |
} |
774 |
l1_allocated = 1;
|
775 |
if (bdrv_pread(bs->file, l1_table_offset,
|
776 |
l1_table, l1_size2) != l1_size2) |
777 |
goto fail;
|
778 |
for(i = 0;i < l1_size; i++) |
779 |
be64_to_cpus(&l1_table[i]); |
780 |
} else {
|
781 |
assert(l1_size == s->l1_size); |
782 |
l1_table = s->l1_table; |
783 |
l1_allocated = 0;
|
784 |
} |
785 |
|
786 |
l2_size = s->l2_size * sizeof(uint64_t);
|
787 |
l2_table = qemu_malloc(l2_size); |
788 |
l1_modified = 0;
|
789 |
for(i = 0; i < l1_size; i++) { |
790 |
l2_offset = l1_table[i]; |
791 |
if (l2_offset) {
|
792 |
old_l2_offset = l2_offset; |
793 |
l2_offset &= ~QCOW_OFLAG_COPIED; |
794 |
l2_modified = 0;
|
795 |
if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
|
796 |
goto fail;
|
797 |
for(j = 0; j < s->l2_size; j++) { |
798 |
offset = be64_to_cpu(l2_table[j]); |
799 |
if (offset != 0) { |
800 |
old_offset = offset; |
801 |
offset &= ~QCOW_OFLAG_COPIED; |
802 |
if (offset & QCOW_OFLAG_COMPRESSED) {
|
803 |
nb_csectors = ((offset >> s->csize_shift) & |
804 |
s->csize_mask) + 1;
|
805 |
if (addend != 0) { |
806 |
int ret;
|
807 |
ret = update_refcount(bs, |
808 |
(offset & s->cluster_offset_mask) & ~511,
|
809 |
nb_csectors * 512, addend);
|
810 |
if (ret < 0) { |
811 |
goto fail;
|
812 |
} |
813 |
|
814 |
/* TODO Flushing once for the whole function should
|
815 |
* be enough */
|
816 |
bdrv_flush(bs->file); |
817 |
} |
818 |
/* compressed clusters are never modified */
|
819 |
refcount = 2;
|
820 |
} else {
|
821 |
if (addend != 0) { |
822 |
refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend); |
823 |
} else {
|
824 |
refcount = get_refcount(bs, offset >> s->cluster_bits); |
825 |
} |
826 |
|
827 |
if (refcount < 0) { |
828 |
goto fail;
|
829 |
} |
830 |
} |
831 |
|
832 |
if (refcount == 1) { |
833 |
offset |= QCOW_OFLAG_COPIED; |
834 |
} |
835 |
if (offset != old_offset) {
|
836 |
l2_table[j] = cpu_to_be64(offset); |
837 |
l2_modified = 1;
|
838 |
} |
839 |
} |
840 |
} |
841 |
if (l2_modified) {
|
842 |
if (bdrv_pwrite_sync(bs->file,
|
843 |
l2_offset, l2_table, l2_size) < 0)
|
844 |
goto fail;
|
845 |
} |
846 |
|
847 |
if (addend != 0) { |
848 |
refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); |
849 |
} else {
|
850 |
refcount = get_refcount(bs, l2_offset >> s->cluster_bits); |
851 |
} |
852 |
if (refcount < 0) { |
853 |
goto fail;
|
854 |
} else if (refcount == 1) { |
855 |
l2_offset |= QCOW_OFLAG_COPIED; |
856 |
} |
857 |
if (l2_offset != old_l2_offset) {
|
858 |
l1_table[i] = l2_offset; |
859 |
l1_modified = 1;
|
860 |
} |
861 |
} |
862 |
} |
863 |
if (l1_modified) {
|
864 |
for(i = 0; i < l1_size; i++) |
865 |
cpu_to_be64s(&l1_table[i]); |
866 |
if (bdrv_pwrite_sync(bs->file, l1_table_offset, l1_table,
|
867 |
l1_size2) < 0)
|
868 |
goto fail;
|
869 |
for(i = 0; i < l1_size; i++) |
870 |
be64_to_cpus(&l1_table[i]); |
871 |
} |
872 |
if (l1_allocated)
|
873 |
qemu_free(l1_table); |
874 |
qemu_free(l2_table); |
875 |
cache_refcount_updates = 0;
|
876 |
write_refcount_block(bs); |
877 |
return 0; |
878 |
fail:
|
879 |
if (l1_allocated)
|
880 |
qemu_free(l1_table); |
881 |
qemu_free(l2_table); |
882 |
cache_refcount_updates = 0;
|
883 |
write_refcount_block(bs); |
884 |
return -EIO;
|
885 |
} |
886 |
|
887 |
|
888 |
|
889 |
|
890 |
/*********************************************************/
|
891 |
/* refcount checking functions */
|
892 |
|
893 |
|
894 |
|
895 |
/*
|
896 |
* Increases the refcount for a range of clusters in a given refcount table.
|
897 |
* This is used to construct a temporary refcount table out of L1 and L2 tables
|
898 |
* which can be compared the the refcount table saved in the image.
|
899 |
*
|
900 |
* Modifies the number of errors in res.
|
901 |
*/
|
902 |
static void inc_refcounts(BlockDriverState *bs, |
903 |
BdrvCheckResult *res, |
904 |
uint16_t *refcount_table, |
905 |
int refcount_table_size,
|
906 |
int64_t offset, int64_t size) |
907 |
{ |
908 |
BDRVQcowState *s = bs->opaque; |
909 |
int64_t start, last, cluster_offset; |
910 |
int k;
|
911 |
|
912 |
if (size <= 0) |
913 |
return;
|
914 |
|
915 |
start = offset & ~(s->cluster_size - 1);
|
916 |
last = (offset + size - 1) & ~(s->cluster_size - 1); |
917 |
for(cluster_offset = start; cluster_offset <= last;
|
918 |
cluster_offset += s->cluster_size) { |
919 |
k = cluster_offset >> s->cluster_bits; |
920 |
if (k < 0) { |
921 |
fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n", |
922 |
cluster_offset); |
923 |
res->corruptions++; |
924 |
} else if (k >= refcount_table_size) { |
925 |
fprintf(stderr, "Warning: cluster offset=0x%" PRIx64 " is after " |
926 |
"the end of the image file, can't properly check refcounts.\n",
|
927 |
cluster_offset); |
928 |
res->check_errors++; |
929 |
} else {
|
930 |
if (++refcount_table[k] == 0) { |
931 |
fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
|
932 |
"\n", cluster_offset);
|
933 |
res->corruptions++; |
934 |
} |
935 |
} |
936 |
} |
937 |
} |
938 |
|
939 |
/*
|
940 |
* Increases the refcount in the given refcount table for the all clusters
|
941 |
* referenced in the L2 table. While doing so, performs some checks on L2
|
942 |
* entries.
|
943 |
*
|
944 |
* Returns the number of errors found by the checks or -errno if an internal
|
945 |
* error occurred.
|
946 |
*/
|
947 |
static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res, |
948 |
uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
|
949 |
int check_copied)
|
950 |
{ |
951 |
BDRVQcowState *s = bs->opaque; |
952 |
uint64_t *l2_table, offset; |
953 |
int i, l2_size, nb_csectors, refcount;
|
954 |
|
955 |
/* Read L2 table from disk */
|
956 |
l2_size = s->l2_size * sizeof(uint64_t);
|
957 |
l2_table = qemu_malloc(l2_size); |
958 |
|
959 |
if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
|
960 |
goto fail;
|
961 |
|
962 |
/* Do the actual checks */
|
963 |
for(i = 0; i < s->l2_size; i++) { |
964 |
offset = be64_to_cpu(l2_table[i]); |
965 |
if (offset != 0) { |
966 |
if (offset & QCOW_OFLAG_COMPRESSED) {
|
967 |
/* Compressed clusters don't have QCOW_OFLAG_COPIED */
|
968 |
if (offset & QCOW_OFLAG_COPIED) {
|
969 |
fprintf(stderr, "ERROR: cluster %" PRId64 ": " |
970 |
"copied flag must never be set for compressed "
|
971 |
"clusters\n", offset >> s->cluster_bits);
|
972 |
offset &= ~QCOW_OFLAG_COPIED; |
973 |
res->corruptions++; |
974 |
} |
975 |
|
976 |
/* Mark cluster as used */
|
977 |
nb_csectors = ((offset >> s->csize_shift) & |
978 |
s->csize_mask) + 1;
|
979 |
offset &= s->cluster_offset_mask; |
980 |
inc_refcounts(bs, res, refcount_table, refcount_table_size, |
981 |
offset & ~511, nb_csectors * 512); |
982 |
} else {
|
983 |
/* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
984 |
if (check_copied) {
|
985 |
uint64_t entry = offset; |
986 |
offset &= ~QCOW_OFLAG_COPIED; |
987 |
refcount = get_refcount(bs, offset >> s->cluster_bits); |
988 |
if (refcount < 0) { |
989 |
fprintf(stderr, "Can't get refcount for offset %"
|
990 |
PRIx64 ": %s\n", entry, strerror(-refcount));
|
991 |
goto fail;
|
992 |
} |
993 |
if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) { |
994 |
fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
|
995 |
PRIx64 " refcount=%d\n", entry, refcount);
|
996 |
res->corruptions++; |
997 |
} |
998 |
} |
999 |
|
1000 |
/* Mark cluster as used */
|
1001 |
offset &= ~QCOW_OFLAG_COPIED; |
1002 |
inc_refcounts(bs, res, refcount_table,refcount_table_size, |
1003 |
offset, s->cluster_size); |
1004 |
|
1005 |
/* Correct offsets are cluster aligned */
|
1006 |
if (offset & (s->cluster_size - 1)) { |
1007 |
fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not " |
1008 |
"properly aligned; L2 entry corrupted.\n", offset);
|
1009 |
res->corruptions++; |
1010 |
} |
1011 |
} |
1012 |
} |
1013 |
} |
1014 |
|
1015 |
qemu_free(l2_table); |
1016 |
return 0; |
1017 |
|
1018 |
fail:
|
1019 |
fprintf(stderr, "ERROR: I/O error in check_refcounts_l2\n");
|
1020 |
qemu_free(l2_table); |
1021 |
return -EIO;
|
1022 |
} |
1023 |
|
1024 |
/*
|
1025 |
* Increases the refcount for the L1 table, its L2 tables and all referenced
|
1026 |
* clusters in the given refcount table. While doing so, performs some checks
|
1027 |
* on L1 and L2 entries.
|
1028 |
*
|
1029 |
* Returns the number of errors found by the checks or -errno if an internal
|
1030 |
* error occurred.
|
1031 |
*/
|
1032 |
static int check_refcounts_l1(BlockDriverState *bs, |
1033 |
BdrvCheckResult *res, |
1034 |
uint16_t *refcount_table, |
1035 |
int refcount_table_size,
|
1036 |
int64_t l1_table_offset, int l1_size,
|
1037 |
int check_copied)
|
1038 |
{ |
1039 |
BDRVQcowState *s = bs->opaque; |
1040 |
uint64_t *l1_table, l2_offset, l1_size2; |
1041 |
int i, refcount, ret;
|
1042 |
|
1043 |
l1_size2 = l1_size * sizeof(uint64_t);
|
1044 |
|
1045 |
/* Mark L1 table as used */
|
1046 |
inc_refcounts(bs, res, refcount_table, refcount_table_size, |
1047 |
l1_table_offset, l1_size2); |
1048 |
|
1049 |
/* Read L1 table entries from disk */
|
1050 |
if (l1_size2 == 0) { |
1051 |
l1_table = NULL;
|
1052 |
} else {
|
1053 |
l1_table = qemu_malloc(l1_size2); |
1054 |
if (bdrv_pread(bs->file, l1_table_offset,
|
1055 |
l1_table, l1_size2) != l1_size2) |
1056 |
goto fail;
|
1057 |
for(i = 0;i < l1_size; i++) |
1058 |
be64_to_cpus(&l1_table[i]); |
1059 |
} |
1060 |
|
1061 |
/* Do the actual checks */
|
1062 |
for(i = 0; i < l1_size; i++) { |
1063 |
l2_offset = l1_table[i]; |
1064 |
if (l2_offset) {
|
1065 |
/* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
1066 |
if (check_copied) {
|
1067 |
refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) |
1068 |
>> s->cluster_bits); |
1069 |
if (refcount < 0) { |
1070 |
fprintf(stderr, "Can't get refcount for l2_offset %"
|
1071 |
PRIx64 ": %s\n", l2_offset, strerror(-refcount));
|
1072 |
goto fail;
|
1073 |
} |
1074 |
if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { |
1075 |
fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
|
1076 |
" refcount=%d\n", l2_offset, refcount);
|
1077 |
res->corruptions++; |
1078 |
} |
1079 |
} |
1080 |
|
1081 |
/* Mark L2 table as used */
|
1082 |
l2_offset &= ~QCOW_OFLAG_COPIED; |
1083 |
inc_refcounts(bs, res, refcount_table, refcount_table_size, |
1084 |
l2_offset, s->cluster_size); |
1085 |
|
1086 |
/* L2 tables are cluster aligned */
|
1087 |
if (l2_offset & (s->cluster_size - 1)) { |
1088 |
fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not " |
1089 |
"cluster aligned; L1 entry corrupted\n", l2_offset);
|
1090 |
res->corruptions++; |
1091 |
} |
1092 |
|
1093 |
/* Process and check L2 entries */
|
1094 |
ret = check_refcounts_l2(bs, res, refcount_table, |
1095 |
refcount_table_size, l2_offset, check_copied); |
1096 |
if (ret < 0) { |
1097 |
goto fail;
|
1098 |
} |
1099 |
} |
1100 |
} |
1101 |
qemu_free(l1_table); |
1102 |
return 0; |
1103 |
|
1104 |
fail:
|
1105 |
fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
|
1106 |
res->check_errors++; |
1107 |
qemu_free(l1_table); |
1108 |
return -EIO;
|
1109 |
} |
1110 |
|
1111 |
/*
|
1112 |
* Checks an image for refcount consistency.
|
1113 |
*
|
1114 |
* Returns 0 if no errors are found, the number of errors in case the image is
|
1115 |
* detected as corrupted, and -errno when an internal error occured.
|
1116 |
*/
|
1117 |
int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res)
|
1118 |
{ |
1119 |
BDRVQcowState *s = bs->opaque; |
1120 |
int64_t size; |
1121 |
int nb_clusters, refcount1, refcount2, i;
|
1122 |
QCowSnapshot *sn; |
1123 |
uint16_t *refcount_table; |
1124 |
int ret;
|
1125 |
|
1126 |
size = bdrv_getlength(bs->file); |
1127 |
nb_clusters = size_to_clusters(s, size); |
1128 |
refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
|
1129 |
|
1130 |
/* header */
|
1131 |
inc_refcounts(bs, res, refcount_table, nb_clusters, |
1132 |
0, s->cluster_size);
|
1133 |
|
1134 |
/* current L1 table */
|
1135 |
ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters, |
1136 |
s->l1_table_offset, s->l1_size, 1);
|
1137 |
if (ret < 0) { |
1138 |
return ret;
|
1139 |
} |
1140 |
|
1141 |
/* snapshots */
|
1142 |
for(i = 0; i < s->nb_snapshots; i++) { |
1143 |
sn = s->snapshots + i; |
1144 |
ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters, |
1145 |
sn->l1_table_offset, sn->l1_size, 0);
|
1146 |
if (ret < 0) { |
1147 |
return ret;
|
1148 |
} |
1149 |
} |
1150 |
inc_refcounts(bs, res, refcount_table, nb_clusters, |
1151 |
s->snapshots_offset, s->snapshots_size); |
1152 |
|
1153 |
/* refcount data */
|
1154 |
inc_refcounts(bs, res, refcount_table, nb_clusters, |
1155 |
s->refcount_table_offset, |
1156 |
s->refcount_table_size * sizeof(uint64_t));
|
1157 |
|
1158 |
for(i = 0; i < s->refcount_table_size; i++) { |
1159 |
uint64_t offset, cluster; |
1160 |
offset = s->refcount_table[i]; |
1161 |
cluster = offset >> s->cluster_bits; |
1162 |
|
1163 |
/* Refcount blocks are cluster aligned */
|
1164 |
if (offset & (s->cluster_size - 1)) { |
1165 |
fprintf(stderr, "ERROR refcount block %d is not "
|
1166 |
"cluster aligned; refcount table entry corrupted\n", i);
|
1167 |
res->corruptions++; |
1168 |
continue;
|
1169 |
} |
1170 |
|
1171 |
if (cluster >= nb_clusters) {
|
1172 |
fprintf(stderr, "ERROR refcount block %d is outside image\n", i);
|
1173 |
res->corruptions++; |
1174 |
continue;
|
1175 |
} |
1176 |
|
1177 |
if (offset != 0) { |
1178 |
inc_refcounts(bs, res, refcount_table, nb_clusters, |
1179 |
offset, s->cluster_size); |
1180 |
if (refcount_table[cluster] != 1) { |
1181 |
fprintf(stderr, "ERROR refcount block %d refcount=%d\n",
|
1182 |
i, refcount_table[cluster]); |
1183 |
res->corruptions++; |
1184 |
} |
1185 |
} |
1186 |
} |
1187 |
|
1188 |
/* compare ref counts */
|
1189 |
for(i = 0; i < nb_clusters; i++) { |
1190 |
refcount1 = get_refcount(bs, i); |
1191 |
if (refcount1 < 0) { |
1192 |
fprintf(stderr, "Can't get refcount for cluster %d: %s\n",
|
1193 |
i, strerror(-refcount1)); |
1194 |
res->check_errors++; |
1195 |
continue;
|
1196 |
} |
1197 |
|
1198 |
refcount2 = refcount_table[i]; |
1199 |
if (refcount1 != refcount2) {
|
1200 |
fprintf(stderr, "%s cluster %d refcount=%d reference=%d\n",
|
1201 |
refcount1 < refcount2 ? "ERROR" : "Leaked", |
1202 |
i, refcount1, refcount2); |
1203 |
if (refcount1 < refcount2) {
|
1204 |
res->corruptions++; |
1205 |
} else {
|
1206 |
res->leaks++; |
1207 |
} |
1208 |
} |
1209 |
} |
1210 |
|
1211 |
qemu_free(refcount_table); |
1212 |
|
1213 |
return 0; |
1214 |
} |
1215 |
|