root / block / qcow2-refcount.c @ 6882c8fa
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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);
|
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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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static int cache_refcount_updates = 0; |
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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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} |
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|
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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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/* 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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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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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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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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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]; |
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if (!refcount_block_offset)
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return 0; |
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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); |
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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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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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} |
142 |
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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)); |
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|
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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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} |
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return refcount_table_clusters << (s->cluster_bits - 3); |
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} |
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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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} |
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|
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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); |
185 |
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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); |
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if (refcount_table_index < s->refcount_table_size) {
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uint64_t refcount_block_offset = |
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s->refcount_table[refcount_table_index]; |
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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); |
198 |
if (ret < 0) { |
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return ret;
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} |
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} |
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return refcount_block_offset;
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} |
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} |
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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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if (cache_refcount_updates) {
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ret = write_refcount_block(bs); |
230 |
if (ret < 0) { |
231 |
return ret;
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} |
233 |
} |
234 |
|
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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); |
237 |
if (new_block < 0) { |
238 |
return new_block;
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} |
240 |
|
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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); |
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#endif
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|
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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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memset(s->refcount_block_cache, 0, s->cluster_size);
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s->refcount_block_cache_offset = new_block; |
251 |
|
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/* The block describes itself, need to update the cache */
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int block_index = (new_block >> s->cluster_bits) &
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((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
255 |
s->refcount_block_cache[block_index] = cpu_to_be16(1);
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256 |
} else {
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/* Described somewhere else. This can recurse at most twice before we
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* arrive at a block that describes itself. */
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ret = update_refcount(bs, new_block, s->cluster_size, 1);
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260 |
if (ret < 0) { |
261 |
goto fail_block;
|
262 |
} |
263 |
|
264 |
/* Initialize the new refcount block only after updating its refcount,
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265 |
* update_refcount uses the refcount cache itself */
|
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memset(s->refcount_block_cache, 0, s->cluster_size);
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s->refcount_block_cache_offset = new_block; |
268 |
} |
269 |
|
270 |
/* Now the new refcount block needs to be written to disk */
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BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE); |
272 |
ret = bdrv_pwrite_sync(bs->file, new_block, s->refcount_block_cache, |
273 |
s->cluster_size); |
274 |
if (ret < 0) { |
275 |
goto fail_block;
|
276 |
} |
277 |
|
278 |
/* If the refcount table is big enough, just hook the block up there */
|
279 |
if (refcount_table_index < s->refcount_table_size) {
|
280 |
uint64_t data64 = cpu_to_be64(new_block); |
281 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP); |
282 |
ret = bdrv_pwrite_sync(bs->file, |
283 |
s->refcount_table_offset + refcount_table_index * sizeof(uint64_t),
|
284 |
&data64, sizeof(data64));
|
285 |
if (ret < 0) { |
286 |
goto fail_block;
|
287 |
} |
288 |
|
289 |
s->refcount_table[refcount_table_index] = new_block; |
290 |
return new_block;
|
291 |
} |
292 |
|
293 |
/*
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294 |
* If we come here, we need to grow the refcount table. Again, a new
|
295 |
* refcount table needs some space and we can't simply allocate to avoid
|
296 |
* endless recursion.
|
297 |
*
|
298 |
* Therefore let's grab new refcount blocks at the end of the image, which
|
299 |
* will describe themselves and the new refcount table. This way we can
|
300 |
* reference them only in the new table and do the switch to the new
|
301 |
* refcount table at once without producing an inconsistent state in
|
302 |
* between.
|
303 |
*/
|
304 |
BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_GROW); |
305 |
|
306 |
/* Calculate the number of refcount blocks needed so far */
|
307 |
uint64_t refcount_block_clusters = 1 << (s->cluster_bits - REFCOUNT_SHIFT);
|
308 |
uint64_t blocks_used = (s->free_cluster_index + |
309 |
refcount_block_clusters - 1) / refcount_block_clusters;
|
310 |
|
311 |
/* And now we need at least one block more for the new metadata */
|
312 |
uint64_t table_size = next_refcount_table_size(s, blocks_used + 1);
|
313 |
uint64_t last_table_size; |
314 |
uint64_t blocks_clusters; |
315 |
do {
|
316 |
uint64_t table_clusters = size_to_clusters(s, table_size); |
317 |
blocks_clusters = 1 +
|
318 |
((table_clusters + refcount_block_clusters - 1)
|
319 |
/ refcount_block_clusters); |
320 |
uint64_t meta_clusters = table_clusters + blocks_clusters; |
321 |
|
322 |
last_table_size = table_size; |
323 |
table_size = next_refcount_table_size(s, blocks_used + |
324 |
((meta_clusters + refcount_block_clusters - 1)
|
325 |
/ refcount_block_clusters)); |
326 |
|
327 |
} while (last_table_size != table_size);
|
328 |
|
329 |
#ifdef DEBUG_ALLOC2
|
330 |
fprintf(stderr, "qcow2: Grow refcount table %" PRId32 " => %" PRId64 "\n", |
331 |
s->refcount_table_size, table_size); |
332 |
#endif
|
333 |
|
334 |
/* Create the new refcount table and blocks */
|
335 |
uint64_t meta_offset = (blocks_used * refcount_block_clusters) * |
336 |
s->cluster_size; |
337 |
uint64_t table_offset = meta_offset + blocks_clusters * s->cluster_size; |
338 |
uint16_t *new_blocks = qemu_mallocz(blocks_clusters * s->cluster_size); |
339 |
uint64_t *new_table = qemu_mallocz(table_size * sizeof(uint64_t));
|
340 |
|
341 |
assert(meta_offset >= (s->free_cluster_index * s->cluster_size)); |
342 |
|
343 |
/* Fill the new refcount table */
|
344 |
memcpy(new_table, s->refcount_table, |
345 |
s->refcount_table_size * sizeof(uint64_t));
|
346 |
new_table[refcount_table_index] = new_block; |
347 |
|
348 |
int i;
|
349 |
for (i = 0; i < blocks_clusters; i++) { |
350 |
new_table[blocks_used + i] = meta_offset + (i * s->cluster_size); |
351 |
} |
352 |
|
353 |
/* Fill the refcount blocks */
|
354 |
uint64_t table_clusters = size_to_clusters(s, table_size * sizeof(uint64_t));
|
355 |
int block = 0; |
356 |
for (i = 0; i < table_clusters + blocks_clusters; i++) { |
357 |
new_blocks[block++] = cpu_to_be16(1);
|
358 |
} |
359 |
|
360 |
/* Write refcount blocks to disk */
|
361 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS); |
362 |
ret = bdrv_pwrite_sync(bs->file, meta_offset, new_blocks, |
363 |
blocks_clusters * s->cluster_size); |
364 |
qemu_free(new_blocks); |
365 |
if (ret < 0) { |
366 |
goto fail_table;
|
367 |
} |
368 |
|
369 |
/* Write refcount table to disk */
|
370 |
for(i = 0; i < table_size; i++) { |
371 |
cpu_to_be64s(&new_table[i]); |
372 |
} |
373 |
|
374 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE); |
375 |
ret = bdrv_pwrite_sync(bs->file, table_offset, new_table, |
376 |
table_size * sizeof(uint64_t));
|
377 |
if (ret < 0) { |
378 |
goto fail_table;
|
379 |
} |
380 |
|
381 |
for(i = 0; i < table_size; i++) { |
382 |
cpu_to_be64s(&new_table[i]); |
383 |
} |
384 |
|
385 |
/* Hook up the new refcount table in the qcow2 header */
|
386 |
uint8_t data[12];
|
387 |
cpu_to_be64w((uint64_t*)data, table_offset); |
388 |
cpu_to_be32w((uint32_t*)(data + 8), table_clusters);
|
389 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE); |
390 |
ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, refcount_table_offset), |
391 |
data, sizeof(data));
|
392 |
if (ret < 0) { |
393 |
goto fail_table;
|
394 |
} |
395 |
|
396 |
/* And switch it in memory */
|
397 |
uint64_t old_table_offset = s->refcount_table_offset; |
398 |
uint64_t old_table_size = s->refcount_table_size; |
399 |
|
400 |
qemu_free(s->refcount_table); |
401 |
s->refcount_table = new_table; |
402 |
s->refcount_table_size = table_size; |
403 |
s->refcount_table_offset = table_offset; |
404 |
|
405 |
/* Free old table. Remember, we must not change free_cluster_index */
|
406 |
uint64_t old_free_cluster_index = s->free_cluster_index; |
407 |
qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
|
408 |
s->free_cluster_index = old_free_cluster_index; |
409 |
|
410 |
ret = load_refcount_block(bs, new_block); |
411 |
if (ret < 0) { |
412 |
goto fail_block;
|
413 |
} |
414 |
|
415 |
return new_block;
|
416 |
|
417 |
fail_table:
|
418 |
qemu_free(new_table); |
419 |
fail_block:
|
420 |
s->refcount_block_cache_offset = 0;
|
421 |
return ret;
|
422 |
} |
423 |
|
424 |
#define REFCOUNTS_PER_SECTOR (512 >> REFCOUNT_SHIFT) |
425 |
static int write_refcount_block_entries(BlockDriverState *bs, |
426 |
int64_t refcount_block_offset, int first_index, int last_index) |
427 |
{ |
428 |
BDRVQcowState *s = bs->opaque; |
429 |
size_t size; |
430 |
int ret;
|
431 |
|
432 |
if (cache_refcount_updates) {
|
433 |
return 0; |
434 |
} |
435 |
|
436 |
if (first_index < 0) { |
437 |
return 0; |
438 |
} |
439 |
|
440 |
first_index &= ~(REFCOUNTS_PER_SECTOR - 1);
|
441 |
last_index = (last_index + REFCOUNTS_PER_SECTOR) |
442 |
& ~(REFCOUNTS_PER_SECTOR - 1);
|
443 |
|
444 |
size = (last_index - first_index) << REFCOUNT_SHIFT; |
445 |
|
446 |
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE_PART); |
447 |
ret = bdrv_pwrite_sync(bs->file, |
448 |
refcount_block_offset + (first_index << REFCOUNT_SHIFT), |
449 |
&s->refcount_block_cache[first_index], size); |
450 |
if (ret < 0) { |
451 |
return ret;
|
452 |
} |
453 |
|
454 |
return 0; |
455 |
} |
456 |
|
457 |
/* XXX: cache several refcount block clusters ? */
|
458 |
static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, |
459 |
int64_t offset, int64_t length, int addend)
|
460 |
{ |
461 |
BDRVQcowState *s = bs->opaque; |
462 |
int64_t start, last, cluster_offset; |
463 |
int64_t refcount_block_offset = 0;
|
464 |
int64_t table_index = -1, old_table_index;
|
465 |
int first_index = -1, last_index = -1; |
466 |
int ret;
|
467 |
|
468 |
#ifdef DEBUG_ALLOC2
|
469 |
printf("update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n", |
470 |
offset, length, addend); |
471 |
#endif
|
472 |
if (length < 0) { |
473 |
return -EINVAL;
|
474 |
} else if (length == 0) { |
475 |
return 0; |
476 |
} |
477 |
|
478 |
start = offset & ~(s->cluster_size - 1);
|
479 |
last = (offset + length - 1) & ~(s->cluster_size - 1); |
480 |
for(cluster_offset = start; cluster_offset <= last;
|
481 |
cluster_offset += s->cluster_size) |
482 |
{ |
483 |
int block_index, refcount;
|
484 |
int64_t cluster_index = cluster_offset >> s->cluster_bits; |
485 |
int64_t new_block; |
486 |
|
487 |
/* Only write refcount block to disk when we are done with it */
|
488 |
old_table_index = table_index; |
489 |
table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
490 |
if ((old_table_index >= 0) && (table_index != old_table_index)) { |
491 |
|
492 |
ret = write_refcount_block_entries(bs, refcount_block_offset, |
493 |
first_index, last_index); |
494 |
if (ret < 0) { |
495 |
return ret;
|
496 |
} |
497 |
|
498 |
first_index = -1;
|
499 |
last_index = -1;
|
500 |
} |
501 |
|
502 |
/* Load the refcount block and allocate it if needed */
|
503 |
new_block = alloc_refcount_block(bs, cluster_index); |
504 |
if (new_block < 0) { |
505 |
ret = new_block; |
506 |
goto fail;
|
507 |
} |
508 |
refcount_block_offset = new_block; |
509 |
|
510 |
/* we can update the count and save it */
|
511 |
block_index = cluster_index & |
512 |
((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
513 |
if (first_index == -1 || block_index < first_index) { |
514 |
first_index = block_index; |
515 |
} |
516 |
if (block_index > last_index) {
|
517 |
last_index = block_index; |
518 |
} |
519 |
|
520 |
refcount = be16_to_cpu(s->refcount_block_cache[block_index]); |
521 |
refcount += addend; |
522 |
if (refcount < 0 || refcount > 0xffff) { |
523 |
ret = -EINVAL; |
524 |
goto fail;
|
525 |
} |
526 |
if (refcount == 0 && cluster_index < s->free_cluster_index) { |
527 |
s->free_cluster_index = cluster_index; |
528 |
} |
529 |
s->refcount_block_cache[block_index] = cpu_to_be16(refcount); |
530 |
} |
531 |
|
532 |
ret = 0;
|
533 |
fail:
|
534 |
|
535 |
/* Write last changed block to disk */
|
536 |
if (refcount_block_offset != 0) { |
537 |
int wret;
|
538 |
wret = write_refcount_block_entries(bs, refcount_block_offset, |
539 |
first_index, last_index); |
540 |
if (wret < 0) { |
541 |
return ret < 0 ? ret : wret; |
542 |
} |
543 |
} |
544 |
|
545 |
/*
|
546 |
* Try do undo any updates if an error is returned (This may succeed in
|
547 |
* some cases like ENOSPC for allocating a new refcount block)
|
548 |
*/
|
549 |
if (ret < 0) { |
550 |
int dummy;
|
551 |
dummy = update_refcount(bs, offset, cluster_offset - offset, -addend); |
552 |
} |
553 |
|
554 |
return ret;
|
555 |
} |
556 |
|
557 |
/*
|
558 |
* Increases or decreases the refcount of a given cluster by one.
|
559 |
* addend must be 1 or -1.
|
560 |
*
|
561 |
* If the return value is non-negative, it is the new refcount of the cluster.
|
562 |
* If it is negative, it is -errno and indicates an error.
|
563 |
*/
|
564 |
static int update_cluster_refcount(BlockDriverState *bs, |
565 |
int64_t cluster_index, |
566 |
int addend)
|
567 |
{ |
568 |
BDRVQcowState *s = bs->opaque; |
569 |
int ret;
|
570 |
|
571 |
ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
|
572 |
if (ret < 0) { |
573 |
return ret;
|
574 |
} |
575 |
|
576 |
return get_refcount(bs, cluster_index);
|
577 |
} |
578 |
|
579 |
|
580 |
|
581 |
/*********************************************************/
|
582 |
/* cluster allocation functions */
|
583 |
|
584 |
|
585 |
|
586 |
/* return < 0 if error */
|
587 |
static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
|
588 |
{ |
589 |
BDRVQcowState *s = bs->opaque; |
590 |
int i, nb_clusters, refcount;
|
591 |
|
592 |
nb_clusters = size_to_clusters(s, size); |
593 |
retry:
|
594 |
for(i = 0; i < nb_clusters; i++) { |
595 |
int64_t next_cluster_index = s->free_cluster_index++; |
596 |
refcount = get_refcount(bs, next_cluster_index); |
597 |
|
598 |
if (refcount < 0) { |
599 |
return refcount;
|
600 |
} else if (refcount != 0) { |
601 |
goto retry;
|
602 |
} |
603 |
} |
604 |
#ifdef DEBUG_ALLOC2
|
605 |
printf("alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n", |
606 |
size, |
607 |
(s->free_cluster_index - nb_clusters) << s->cluster_bits); |
608 |
#endif
|
609 |
return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
|
610 |
} |
611 |
|
612 |
int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size) |
613 |
{ |
614 |
int64_t offset; |
615 |
int ret;
|
616 |
|
617 |
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC); |
618 |
offset = alloc_clusters_noref(bs, size); |
619 |
if (offset < 0) { |
620 |
return offset;
|
621 |
} |
622 |
|
623 |
ret = update_refcount(bs, offset, size, 1);
|
624 |
if (ret < 0) { |
625 |
return ret;
|
626 |
} |
627 |
return offset;
|
628 |
} |
629 |
|
630 |
/* only used to allocate compressed sectors. We try to allocate
|
631 |
contiguous sectors. size must be <= cluster_size */
|
632 |
int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
|
633 |
{ |
634 |
BDRVQcowState *s = bs->opaque; |
635 |
int64_t offset, cluster_offset; |
636 |
int free_in_cluster;
|
637 |
|
638 |
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_BYTES); |
639 |
assert(size > 0 && size <= s->cluster_size);
|
640 |
if (s->free_byte_offset == 0) { |
641 |
s->free_byte_offset = qcow2_alloc_clusters(bs, s->cluster_size); |
642 |
if (s->free_byte_offset < 0) { |
643 |
return s->free_byte_offset;
|
644 |
} |
645 |
} |
646 |
redo:
|
647 |
free_in_cluster = s->cluster_size - |
648 |
(s->free_byte_offset & (s->cluster_size - 1));
|
649 |
if (size <= free_in_cluster) {
|
650 |
/* enough space in current cluster */
|
651 |
offset = s->free_byte_offset; |
652 |
s->free_byte_offset += size; |
653 |
free_in_cluster -= size; |
654 |
if (free_in_cluster == 0) |
655 |
s->free_byte_offset = 0;
|
656 |
if ((offset & (s->cluster_size - 1)) != 0) |
657 |
update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
658 |
} else {
|
659 |
offset = qcow2_alloc_clusters(bs, s->cluster_size); |
660 |
if (offset < 0) { |
661 |
return offset;
|
662 |
} |
663 |
cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
|
664 |
if ((cluster_offset + s->cluster_size) == offset) {
|
665 |
/* we are lucky: contiguous data */
|
666 |
offset = s->free_byte_offset; |
667 |
update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
|
668 |
s->free_byte_offset += size; |
669 |
} else {
|
670 |
s->free_byte_offset = offset; |
671 |
goto redo;
|
672 |
} |
673 |
} |
674 |
return offset;
|
675 |
} |
676 |
|
677 |
void qcow2_free_clusters(BlockDriverState *bs,
|
678 |
int64_t offset, int64_t size) |
679 |
{ |
680 |
int ret;
|
681 |
|
682 |
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE); |
683 |
ret = update_refcount(bs, offset, size, -1);
|
684 |
if (ret < 0) { |
685 |
fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
|
686 |
/* TODO Remember the clusters to free them later and avoid leaking */
|
687 |
} |
688 |
} |
689 |
|
690 |
/*
|
691 |
* free_any_clusters
|
692 |
*
|
693 |
* free clusters according to its type: compressed or not
|
694 |
*
|
695 |
*/
|
696 |
|
697 |
void qcow2_free_any_clusters(BlockDriverState *bs,
|
698 |
uint64_t cluster_offset, int nb_clusters)
|
699 |
{ |
700 |
BDRVQcowState *s = bs->opaque; |
701 |
|
702 |
/* free the cluster */
|
703 |
|
704 |
if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
|
705 |
int nb_csectors;
|
706 |
nb_csectors = ((cluster_offset >> s->csize_shift) & |
707 |
s->csize_mask) + 1;
|
708 |
qcow2_free_clusters(bs, |
709 |
(cluster_offset & s->cluster_offset_mask) & ~511,
|
710 |
nb_csectors * 512);
|
711 |
return;
|
712 |
} |
713 |
|
714 |
qcow2_free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits); |
715 |
|
716 |
return;
|
717 |
} |
718 |
|
719 |
|
720 |
|
721 |
/*********************************************************/
|
722 |
/* snapshots and image creation */
|
723 |
|
724 |
|
725 |
|
726 |
void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
|
727 |
int64_t size) |
728 |
{ |
729 |
int refcount;
|
730 |
int64_t start, last, cluster_offset; |
731 |
uint16_t *p; |
732 |
|
733 |
start = offset & ~(s->cluster_size - 1);
|
734 |
last = (offset + size - 1) & ~(s->cluster_size - 1); |
735 |
for(cluster_offset = start; cluster_offset <= last;
|
736 |
cluster_offset += s->cluster_size) { |
737 |
p = &s->refcount_block[cluster_offset >> s->cluster_bits]; |
738 |
refcount = be16_to_cpu(*p); |
739 |
refcount++; |
740 |
*p = cpu_to_be16(refcount); |
741 |
} |
742 |
} |
743 |
|
744 |
/* update the refcounts of snapshots and the copied flag */
|
745 |
int qcow2_update_snapshot_refcount(BlockDriverState *bs,
|
746 |
int64_t l1_table_offset, int l1_size, int addend) |
747 |
{ |
748 |
BDRVQcowState *s = bs->opaque; |
749 |
uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; |
750 |
int64_t old_offset, old_l2_offset; |
751 |
int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount;
|
752 |
|
753 |
qcow2_l2_cache_reset(bs); |
754 |
cache_refcount_updates = 1;
|
755 |
|
756 |
l2_table = NULL;
|
757 |
l1_table = NULL;
|
758 |
l1_size2 = l1_size * sizeof(uint64_t);
|
759 |
if (l1_table_offset != s->l1_table_offset) {
|
760 |
if (l1_size2 != 0) { |
761 |
l1_table = qemu_mallocz(align_offset(l1_size2, 512));
|
762 |
} else {
|
763 |
l1_table = NULL;
|
764 |
} |
765 |
l1_allocated = 1;
|
766 |
if (bdrv_pread(bs->file, l1_table_offset,
|
767 |
l1_table, l1_size2) != l1_size2) |
768 |
goto fail;
|
769 |
for(i = 0;i < l1_size; i++) |
770 |
be64_to_cpus(&l1_table[i]); |
771 |
} else {
|
772 |
assert(l1_size == s->l1_size); |
773 |
l1_table = s->l1_table; |
774 |
l1_allocated = 0;
|
775 |
} |
776 |
|
777 |
l2_size = s->l2_size * sizeof(uint64_t);
|
778 |
l2_table = qemu_malloc(l2_size); |
779 |
l1_modified = 0;
|
780 |
for(i = 0; i < l1_size; i++) { |
781 |
l2_offset = l1_table[i]; |
782 |
if (l2_offset) {
|
783 |
old_l2_offset = l2_offset; |
784 |
l2_offset &= ~QCOW_OFLAG_COPIED; |
785 |
l2_modified = 0;
|
786 |
if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
|
787 |
goto fail;
|
788 |
for(j = 0; j < s->l2_size; j++) { |
789 |
offset = be64_to_cpu(l2_table[j]); |
790 |
if (offset != 0) { |
791 |
old_offset = offset; |
792 |
offset &= ~QCOW_OFLAG_COPIED; |
793 |
if (offset & QCOW_OFLAG_COMPRESSED) {
|
794 |
nb_csectors = ((offset >> s->csize_shift) & |
795 |
s->csize_mask) + 1;
|
796 |
if (addend != 0) { |
797 |
int ret;
|
798 |
ret = update_refcount(bs, |
799 |
(offset & s->cluster_offset_mask) & ~511,
|
800 |
nb_csectors * 512, addend);
|
801 |
if (ret < 0) { |
802 |
goto fail;
|
803 |
} |
804 |
} |
805 |
/* compressed clusters are never modified */
|
806 |
refcount = 2;
|
807 |
} else {
|
808 |
if (addend != 0) { |
809 |
refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend); |
810 |
} else {
|
811 |
refcount = get_refcount(bs, offset >> s->cluster_bits); |
812 |
} |
813 |
|
814 |
if (refcount < 0) { |
815 |
goto fail;
|
816 |
} |
817 |
} |
818 |
|
819 |
if (refcount == 1) { |
820 |
offset |= QCOW_OFLAG_COPIED; |
821 |
} |
822 |
if (offset != old_offset) {
|
823 |
l2_table[j] = cpu_to_be64(offset); |
824 |
l2_modified = 1;
|
825 |
} |
826 |
} |
827 |
} |
828 |
if (l2_modified) {
|
829 |
if (bdrv_pwrite_sync(bs->file,
|
830 |
l2_offset, l2_table, l2_size) < 0)
|
831 |
goto fail;
|
832 |
} |
833 |
|
834 |
if (addend != 0) { |
835 |
refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); |
836 |
} else {
|
837 |
refcount = get_refcount(bs, l2_offset >> s->cluster_bits); |
838 |
} |
839 |
if (refcount < 0) { |
840 |
goto fail;
|
841 |
} else if (refcount == 1) { |
842 |
l2_offset |= QCOW_OFLAG_COPIED; |
843 |
} |
844 |
if (l2_offset != old_l2_offset) {
|
845 |
l1_table[i] = l2_offset; |
846 |
l1_modified = 1;
|
847 |
} |
848 |
} |
849 |
} |
850 |
if (l1_modified) {
|
851 |
for(i = 0; i < l1_size; i++) |
852 |
cpu_to_be64s(&l1_table[i]); |
853 |
if (bdrv_pwrite_sync(bs->file, l1_table_offset, l1_table,
|
854 |
l1_size2) < 0)
|
855 |
goto fail;
|
856 |
for(i = 0; i < l1_size; i++) |
857 |
be64_to_cpus(&l1_table[i]); |
858 |
} |
859 |
if (l1_allocated)
|
860 |
qemu_free(l1_table); |
861 |
qemu_free(l2_table); |
862 |
cache_refcount_updates = 0;
|
863 |
write_refcount_block(bs); |
864 |
return 0; |
865 |
fail:
|
866 |
if (l1_allocated)
|
867 |
qemu_free(l1_table); |
868 |
qemu_free(l2_table); |
869 |
cache_refcount_updates = 0;
|
870 |
write_refcount_block(bs); |
871 |
return -EIO;
|
872 |
} |
873 |
|
874 |
|
875 |
|
876 |
|
877 |
/*********************************************************/
|
878 |
/* refcount checking functions */
|
879 |
|
880 |
|
881 |
|
882 |
/*
|
883 |
* Increases the refcount for a range of clusters in a given refcount table.
|
884 |
* This is used to construct a temporary refcount table out of L1 and L2 tables
|
885 |
* which can be compared the the refcount table saved in the image.
|
886 |
*
|
887 |
* Returns the number of errors in the image that were found
|
888 |
*/
|
889 |
static int inc_refcounts(BlockDriverState *bs, |
890 |
uint16_t *refcount_table, |
891 |
int refcount_table_size,
|
892 |
int64_t offset, int64_t size) |
893 |
{ |
894 |
BDRVQcowState *s = bs->opaque; |
895 |
int64_t start, last, cluster_offset; |
896 |
int k;
|
897 |
int errors = 0; |
898 |
|
899 |
if (size <= 0) |
900 |
return 0; |
901 |
|
902 |
start = offset & ~(s->cluster_size - 1);
|
903 |
last = (offset + size - 1) & ~(s->cluster_size - 1); |
904 |
for(cluster_offset = start; cluster_offset <= last;
|
905 |
cluster_offset += s->cluster_size) { |
906 |
k = cluster_offset >> s->cluster_bits; |
907 |
if (k < 0 || k >= refcount_table_size) { |
908 |
fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n", |
909 |
cluster_offset); |
910 |
errors++; |
911 |
} else {
|
912 |
if (++refcount_table[k] == 0) { |
913 |
fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
|
914 |
"\n", cluster_offset);
|
915 |
errors++; |
916 |
} |
917 |
} |
918 |
} |
919 |
|
920 |
return errors;
|
921 |
} |
922 |
|
923 |
/*
|
924 |
* Increases the refcount in the given refcount table for the all clusters
|
925 |
* referenced in the L2 table. While doing so, performs some checks on L2
|
926 |
* entries.
|
927 |
*
|
928 |
* Returns the number of errors found by the checks or -errno if an internal
|
929 |
* error occurred.
|
930 |
*/
|
931 |
static int check_refcounts_l2(BlockDriverState *bs, |
932 |
uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
|
933 |
int check_copied)
|
934 |
{ |
935 |
BDRVQcowState *s = bs->opaque; |
936 |
uint64_t *l2_table, offset; |
937 |
int i, l2_size, nb_csectors, refcount;
|
938 |
int errors = 0; |
939 |
|
940 |
/* Read L2 table from disk */
|
941 |
l2_size = s->l2_size * sizeof(uint64_t);
|
942 |
l2_table = qemu_malloc(l2_size); |
943 |
|
944 |
if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
|
945 |
goto fail;
|
946 |
|
947 |
/* Do the actual checks */
|
948 |
for(i = 0; i < s->l2_size; i++) { |
949 |
offset = be64_to_cpu(l2_table[i]); |
950 |
if (offset != 0) { |
951 |
if (offset & QCOW_OFLAG_COMPRESSED) {
|
952 |
/* Compressed clusters don't have QCOW_OFLAG_COPIED */
|
953 |
if (offset & QCOW_OFLAG_COPIED) {
|
954 |
fprintf(stderr, "ERROR: cluster %" PRId64 ": " |
955 |
"copied flag must never be set for compressed "
|
956 |
"clusters\n", offset >> s->cluster_bits);
|
957 |
offset &= ~QCOW_OFLAG_COPIED; |
958 |
errors++; |
959 |
} |
960 |
|
961 |
/* Mark cluster as used */
|
962 |
nb_csectors = ((offset >> s->csize_shift) & |
963 |
s->csize_mask) + 1;
|
964 |
offset &= s->cluster_offset_mask; |
965 |
errors += inc_refcounts(bs, refcount_table, |
966 |
refcount_table_size, |
967 |
offset & ~511, nb_csectors * 512); |
968 |
} else {
|
969 |
/* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
970 |
if (check_copied) {
|
971 |
uint64_t entry = offset; |
972 |
offset &= ~QCOW_OFLAG_COPIED; |
973 |
refcount = get_refcount(bs, offset >> s->cluster_bits); |
974 |
if (refcount < 0) { |
975 |
fprintf(stderr, "Can't get refcount for offset %"
|
976 |
PRIx64 ": %s\n", entry, strerror(-refcount));
|
977 |
} |
978 |
if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) { |
979 |
fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
|
980 |
PRIx64 " refcount=%d\n", entry, refcount);
|
981 |
errors++; |
982 |
} |
983 |
} |
984 |
|
985 |
/* Mark cluster as used */
|
986 |
offset &= ~QCOW_OFLAG_COPIED; |
987 |
errors += inc_refcounts(bs, refcount_table, |
988 |
refcount_table_size, |
989 |
offset, s->cluster_size); |
990 |
|
991 |
/* Correct offsets are cluster aligned */
|
992 |
if (offset & (s->cluster_size - 1)) { |
993 |
fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not " |
994 |
"properly aligned; L2 entry corrupted.\n", offset);
|
995 |
errors++; |
996 |
} |
997 |
} |
998 |
} |
999 |
} |
1000 |
|
1001 |
qemu_free(l2_table); |
1002 |
return errors;
|
1003 |
|
1004 |
fail:
|
1005 |
fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
|
1006 |
qemu_free(l2_table); |
1007 |
return -EIO;
|
1008 |
} |
1009 |
|
1010 |
/*
|
1011 |
* Increases the refcount for the L1 table, its L2 tables and all referenced
|
1012 |
* clusters in the given refcount table. While doing so, performs some checks
|
1013 |
* on L1 and L2 entries.
|
1014 |
*
|
1015 |
* Returns the number of errors found by the checks or -errno if an internal
|
1016 |
* error occurred.
|
1017 |
*/
|
1018 |
static int check_refcounts_l1(BlockDriverState *bs, |
1019 |
uint16_t *refcount_table, |
1020 |
int refcount_table_size,
|
1021 |
int64_t l1_table_offset, int l1_size,
|
1022 |
int check_copied)
|
1023 |
{ |
1024 |
BDRVQcowState *s = bs->opaque; |
1025 |
uint64_t *l1_table, l2_offset, l1_size2; |
1026 |
int i, refcount, ret;
|
1027 |
int errors = 0; |
1028 |
|
1029 |
l1_size2 = l1_size * sizeof(uint64_t);
|
1030 |
|
1031 |
/* Mark L1 table as used */
|
1032 |
errors += inc_refcounts(bs, refcount_table, refcount_table_size, |
1033 |
l1_table_offset, l1_size2); |
1034 |
|
1035 |
/* Read L1 table entries from disk */
|
1036 |
if (l1_size2 == 0) { |
1037 |
l1_table = NULL;
|
1038 |
} else {
|
1039 |
l1_table = qemu_malloc(l1_size2); |
1040 |
if (bdrv_pread(bs->file, l1_table_offset,
|
1041 |
l1_table, l1_size2) != l1_size2) |
1042 |
goto fail;
|
1043 |
for(i = 0;i < l1_size; i++) |
1044 |
be64_to_cpus(&l1_table[i]); |
1045 |
} |
1046 |
|
1047 |
/* Do the actual checks */
|
1048 |
for(i = 0; i < l1_size; i++) { |
1049 |
l2_offset = l1_table[i]; |
1050 |
if (l2_offset) {
|
1051 |
/* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
|
1052 |
if (check_copied) {
|
1053 |
refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) |
1054 |
>> s->cluster_bits); |
1055 |
if (refcount < 0) { |
1056 |
fprintf(stderr, "Can't get refcount for l2_offset %"
|
1057 |
PRIx64 ": %s\n", l2_offset, strerror(-refcount));
|
1058 |
} |
1059 |
if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { |
1060 |
fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
|
1061 |
" refcount=%d\n", l2_offset, refcount);
|
1062 |
errors++; |
1063 |
} |
1064 |
} |
1065 |
|
1066 |
/* Mark L2 table as used */
|
1067 |
l2_offset &= ~QCOW_OFLAG_COPIED; |
1068 |
errors += inc_refcounts(bs, refcount_table, |
1069 |
refcount_table_size, |
1070 |
l2_offset, |
1071 |
s->cluster_size); |
1072 |
|
1073 |
/* L2 tables are cluster aligned */
|
1074 |
if (l2_offset & (s->cluster_size - 1)) { |
1075 |
fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not " |
1076 |
"cluster aligned; L1 entry corrupted\n", l2_offset);
|
1077 |
errors++; |
1078 |
} |
1079 |
|
1080 |
/* Process and check L2 entries */
|
1081 |
ret = check_refcounts_l2(bs, refcount_table, refcount_table_size, |
1082 |
l2_offset, check_copied); |
1083 |
if (ret < 0) { |
1084 |
goto fail;
|
1085 |
} |
1086 |
errors += ret; |
1087 |
} |
1088 |
} |
1089 |
qemu_free(l1_table); |
1090 |
return errors;
|
1091 |
|
1092 |
fail:
|
1093 |
fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
|
1094 |
qemu_free(l1_table); |
1095 |
return -EIO;
|
1096 |
} |
1097 |
|
1098 |
/*
|
1099 |
* Checks an image for refcount consistency.
|
1100 |
*
|
1101 |
* Returns 0 if no errors are found, the number of errors in case the image is
|
1102 |
* detected as corrupted, and -errno when an internal error occured.
|
1103 |
*/
|
1104 |
int qcow2_check_refcounts(BlockDriverState *bs)
|
1105 |
{ |
1106 |
BDRVQcowState *s = bs->opaque; |
1107 |
int64_t size; |
1108 |
int nb_clusters, refcount1, refcount2, i;
|
1109 |
QCowSnapshot *sn; |
1110 |
uint16_t *refcount_table; |
1111 |
int ret, errors = 0; |
1112 |
|
1113 |
size = bdrv_getlength(bs->file); |
1114 |
nb_clusters = size_to_clusters(s, size); |
1115 |
refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
|
1116 |
|
1117 |
/* header */
|
1118 |
errors += inc_refcounts(bs, refcount_table, nb_clusters, |
1119 |
0, s->cluster_size);
|
1120 |
|
1121 |
/* current L1 table */
|
1122 |
ret = check_refcounts_l1(bs, refcount_table, nb_clusters, |
1123 |
s->l1_table_offset, s->l1_size, 1);
|
1124 |
if (ret < 0) { |
1125 |
return ret;
|
1126 |
} |
1127 |
errors += ret; |
1128 |
|
1129 |
/* snapshots */
|
1130 |
for(i = 0; i < s->nb_snapshots; i++) { |
1131 |
sn = s->snapshots + i; |
1132 |
check_refcounts_l1(bs, refcount_table, nb_clusters, |
1133 |
sn->l1_table_offset, sn->l1_size, 0);
|
1134 |
} |
1135 |
errors += inc_refcounts(bs, refcount_table, nb_clusters, |
1136 |
s->snapshots_offset, s->snapshots_size); |
1137 |
|
1138 |
/* refcount data */
|
1139 |
errors += inc_refcounts(bs, refcount_table, nb_clusters, |
1140 |
s->refcount_table_offset, |
1141 |
s->refcount_table_size * sizeof(uint64_t));
|
1142 |
for(i = 0; i < s->refcount_table_size; i++) { |
1143 |
uint64_t offset, cluster; |
1144 |
offset = s->refcount_table[i]; |
1145 |
cluster = offset >> s->cluster_bits; |
1146 |
|
1147 |
/* Refcount blocks are cluster aligned */
|
1148 |
if (offset & (s->cluster_size - 1)) { |
1149 |
fprintf(stderr, "ERROR refcount block %d is not "
|
1150 |
"cluster aligned; refcount table entry corrupted\n", i);
|
1151 |
errors++; |
1152 |
continue;
|
1153 |
} |
1154 |
|
1155 |
if (cluster >= nb_clusters) {
|
1156 |
fprintf(stderr, "ERROR refcount block %d is outside image\n", i);
|
1157 |
errors++; |
1158 |
continue;
|
1159 |
} |
1160 |
|
1161 |
if (offset != 0) { |
1162 |
errors += inc_refcounts(bs, refcount_table, nb_clusters, |
1163 |
offset, s->cluster_size); |
1164 |
if (refcount_table[cluster] != 1) { |
1165 |
fprintf(stderr, "ERROR refcount block %d refcount=%d\n",
|
1166 |
i, refcount_table[cluster]); |
1167 |
} |
1168 |
} |
1169 |
} |
1170 |
|
1171 |
/* compare ref counts */
|
1172 |
for(i = 0; i < nb_clusters; i++) { |
1173 |
refcount1 = get_refcount(bs, i); |
1174 |
if (refcount1 < 0) { |
1175 |
fprintf(stderr, "Can't get refcount for cluster %d: %s\n",
|
1176 |
i, strerror(-refcount1)); |
1177 |
} |
1178 |
|
1179 |
refcount2 = refcount_table[i]; |
1180 |
if (refcount1 != refcount2) {
|
1181 |
fprintf(stderr, "ERROR cluster %d refcount=%d reference=%d\n",
|
1182 |
i, refcount1, refcount2); |
1183 |
errors++; |
1184 |
} |
1185 |
} |
1186 |
|
1187 |
qemu_free(refcount_table); |
1188 |
|
1189 |
return errors;
|
1190 |
} |
1191 |
|