BLOCK_OBJS=cutils.o cache-utils.o qemu-malloc.o qemu-option.o module.o
BLOCK_OBJS+=block/cow.o block/qcow.o aes.o block/vmdk.o block/cloop.o
BLOCK_OBJS+=block/dmg.o block/bochs.o block/vpc.o block/vvfat.o
-BLOCK_OBJS+=block/qcow2.o block/qcow2-refcount.o
+BLOCK_OBJS+=block/qcow2.o block/qcow2-refcount.o block/qcow2-cluster.o
BLOCK_OBJS+=block/parallels.o block/nbd.o
BLOCK_OBJS+=nbd.o block.o aio.o
--- /dev/null
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <zlib.h>
+
+#include "qemu-common.h"
+#include "block_int.h"
+#include "block/qcow2.h"
+
+int grow_l1_table(BlockDriverState *bs, int min_size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int new_l1_size, new_l1_size2, ret, i;
+ uint64_t *new_l1_table;
+ uint64_t new_l1_table_offset;
+ uint8_t data[12];
+
+ new_l1_size = s->l1_size;
+ if (min_size <= new_l1_size)
+ return 0;
+ while (min_size > new_l1_size) {
+ new_l1_size = (new_l1_size * 3 + 1) / 2;
+ }
+#ifdef DEBUG_ALLOC2
+ printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size);
+#endif
+
+ new_l1_size2 = sizeof(uint64_t) * new_l1_size;
+ new_l1_table = qemu_mallocz(new_l1_size2);
+ memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
+
+ /* write new table (align to cluster) */
+ new_l1_table_offset = alloc_clusters(bs, new_l1_size2);
+
+ for(i = 0; i < s->l1_size; i++)
+ new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
+ ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2);
+ if (ret != new_l1_size2)
+ goto fail;
+ for(i = 0; i < s->l1_size; i++)
+ new_l1_table[i] = be64_to_cpu(new_l1_table[i]);
+
+ /* set new table */
+ cpu_to_be32w((uint32_t*)data, new_l1_size);
+ cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset);
+ if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data,
+ sizeof(data)) != sizeof(data))
+ goto fail;
+ qemu_free(s->l1_table);
+ free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
+ s->l1_table_offset = new_l1_table_offset;
+ s->l1_table = new_l1_table;
+ s->l1_size = new_l1_size;
+ return 0;
+ fail:
+ qemu_free(s->l1_table);
+ return -EIO;
+}
+
+void l2_cache_reset(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+
+ memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
+ memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
+ memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
+}
+
+static inline int l2_cache_new_entry(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint32_t min_count;
+ int min_index, i;
+
+ /* find a new entry in the least used one */
+ min_index = 0;
+ min_count = 0xffffffff;
+ for(i = 0; i < L2_CACHE_SIZE; i++) {
+ if (s->l2_cache_counts[i] < min_count) {
+ min_count = s->l2_cache_counts[i];
+ min_index = i;
+ }
+ }
+ return min_index;
+}
+
+/*
+ * seek_l2_table
+ *
+ * seek l2_offset in the l2_cache table
+ * if not found, return NULL,
+ * if found,
+ * increments the l2 cache hit count of the entry,
+ * if counter overflow, divide by two all counters
+ * return the pointer to the l2 cache entry
+ *
+ */
+
+static uint64_t *seek_l2_table(BDRVQcowState *s, uint64_t l2_offset)
+{
+ int i, j;
+
+ for(i = 0; i < L2_CACHE_SIZE; i++) {
+ if (l2_offset == s->l2_cache_offsets[i]) {
+ /* increment the hit count */
+ if (++s->l2_cache_counts[i] == 0xffffffff) {
+ for(j = 0; j < L2_CACHE_SIZE; j++) {
+ s->l2_cache_counts[j] >>= 1;
+ }
+ }
+ return s->l2_cache + (i << s->l2_bits);
+ }
+ }
+ return NULL;
+}
+
+/*
+ * l2_load
+ *
+ * Loads a L2 table into memory. If the table is in the cache, the cache
+ * is used; otherwise the L2 table is loaded from the image file.
+ *
+ * Returns a pointer to the L2 table on success, or NULL if the read from
+ * the image file failed.
+ */
+
+static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset)
+{
+ BDRVQcowState *s = bs->opaque;
+ int min_index;
+ uint64_t *l2_table;
+
+ /* seek if the table for the given offset is in the cache */
+
+ l2_table = seek_l2_table(s, l2_offset);
+ if (l2_table != NULL)
+ return l2_table;
+
+ /* not found: load a new entry in the least used one */
+
+ min_index = l2_cache_new_entry(bs);
+ l2_table = s->l2_cache + (min_index << s->l2_bits);
+ if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
+ s->l2_size * sizeof(uint64_t))
+ return NULL;
+ s->l2_cache_offsets[min_index] = l2_offset;
+ s->l2_cache_counts[min_index] = 1;
+
+ return l2_table;
+}
+
+/*
+ * l2_allocate
+ *
+ * Allocate a new l2 entry in the file. If l1_index points to an already
+ * used entry in the L2 table (i.e. we are doing a copy on write for the L2
+ * table) copy the contents of the old L2 table into the newly allocated one.
+ * Otherwise the new table is initialized with zeros.
+ *
+ */
+
+static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index)
+{
+ BDRVQcowState *s = bs->opaque;
+ int min_index;
+ uint64_t old_l2_offset, tmp;
+ uint64_t *l2_table, l2_offset;
+
+ old_l2_offset = s->l1_table[l1_index];
+
+ /* allocate a new l2 entry */
+
+ l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
+
+ /* update the L1 entry */
+
+ s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED;
+
+ tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED);
+ if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp),
+ &tmp, sizeof(tmp)) != sizeof(tmp))
+ return NULL;
+
+ /* allocate a new entry in the l2 cache */
+
+ min_index = l2_cache_new_entry(bs);
+ l2_table = s->l2_cache + (min_index << s->l2_bits);
+
+ if (old_l2_offset == 0) {
+ /* if there was no old l2 table, clear the new table */
+ memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
+ } else {
+ /* if there was an old l2 table, read it from the disk */
+ if (bdrv_pread(s->hd, old_l2_offset,
+ l2_table, s->l2_size * sizeof(uint64_t)) !=
+ s->l2_size * sizeof(uint64_t))
+ return NULL;
+ }
+ /* write the l2 table to the file */
+ if (bdrv_pwrite(s->hd, l2_offset,
+ l2_table, s->l2_size * sizeof(uint64_t)) !=
+ s->l2_size * sizeof(uint64_t))
+ return NULL;
+
+ /* update the l2 cache entry */
+
+ s->l2_cache_offsets[min_index] = l2_offset;
+ s->l2_cache_counts[min_index] = 1;
+
+ return l2_table;
+}
+
+static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size,
+ uint64_t *l2_table, uint64_t start, uint64_t mask)
+{
+ int i;
+ uint64_t offset = be64_to_cpu(l2_table[0]) & ~mask;
+
+ if (!offset)
+ return 0;
+
+ for (i = start; i < start + nb_clusters; i++)
+ if (offset + i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask))
+ break;
+
+ return (i - start);
+}
+
+static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table)
+{
+ int i = 0;
+
+ while(nb_clusters-- && l2_table[i] == 0)
+ i++;
+
+ return i;
+}
+
+/* The crypt function is compatible with the linux cryptoloop
+ algorithm for < 4 GB images. NOTE: out_buf == in_buf is
+ supported */
+void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+ uint8_t *out_buf, const uint8_t *in_buf,
+ int nb_sectors, int enc,
+ const AES_KEY *key)
+{
+ union {
+ uint64_t ll[2];
+ uint8_t b[16];
+ } ivec;
+ int i;
+
+ for(i = 0; i < nb_sectors; i++) {
+ ivec.ll[0] = cpu_to_le64(sector_num);
+ ivec.ll[1] = 0;
+ AES_cbc_encrypt(in_buf, out_buf, 512, key,
+ ivec.b, enc);
+ sector_num++;
+ in_buf += 512;
+ out_buf += 512;
+ }
+}
+
+
+static int qcow_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ BDRVQcowState *s = bs->opaque;
+ int ret, index_in_cluster, n, n1;
+ uint64_t cluster_offset;
+
+ while (nb_sectors > 0) {
+ n = nb_sectors;
+ cluster_offset = get_cluster_offset(bs, sector_num << 9, &n);
+ index_in_cluster = sector_num & (s->cluster_sectors - 1);
+ if (!cluster_offset) {
+ if (bs->backing_hd) {
+ /* read from the base image */
+ n1 = backing_read1(bs->backing_hd, sector_num, buf, n);
+ if (n1 > 0) {
+ ret = bdrv_read(bs->backing_hd, sector_num, buf, n1);
+ if (ret < 0)
+ return -1;
+ }
+ } else {
+ memset(buf, 0, 512 * n);
+ }
+ } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
+ if (decompress_cluster(s, cluster_offset) < 0)
+ return -1;
+ memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);
+ } else {
+ ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);
+ if (ret != n * 512)
+ return -1;
+ if (s->crypt_method) {
+ encrypt_sectors(s, sector_num, buf, buf, n, 0,
+ &s->aes_decrypt_key);
+ }
+ }
+ nb_sectors -= n;
+ sector_num += n;
+ buf += n * 512;
+ }
+ return 0;
+}
+
+static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
+ uint64_t cluster_offset, int n_start, int n_end)
+{
+ BDRVQcowState *s = bs->opaque;
+ int n, ret;
+
+ n = n_end - n_start;
+ if (n <= 0)
+ return 0;
+ ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n);
+ if (ret < 0)
+ return ret;
+ if (s->crypt_method) {
+ encrypt_sectors(s, start_sect + n_start,
+ s->cluster_data,
+ s->cluster_data, n, 1,
+ &s->aes_encrypt_key);
+ }
+ ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start,
+ s->cluster_data, n);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+
+/*
+ * get_cluster_offset
+ *
+ * For a given offset of the disk image, return cluster offset in
+ * qcow2 file.
+ *
+ * on entry, *num is the number of contiguous clusters we'd like to
+ * access following offset.
+ *
+ * on exit, *num is the number of contiguous clusters we can read.
+ *
+ * Return 1, if the offset is found
+ * Return 0, otherwise.
+ *
+ */
+
+uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int *num)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l1_index, l2_index;
+ uint64_t l2_offset, *l2_table, cluster_offset;
+ int l1_bits, c;
+ int index_in_cluster, nb_available, nb_needed, nb_clusters;
+
+ index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1);
+ nb_needed = *num + index_in_cluster;
+
+ l1_bits = s->l2_bits + s->cluster_bits;
+
+ /* compute how many bytes there are between the offset and
+ * the end of the l1 entry
+ */
+
+ nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1));
+
+ /* compute the number of available sectors */
+
+ nb_available = (nb_available >> 9) + index_in_cluster;
+
+ if (nb_needed > nb_available) {
+ nb_needed = nb_available;
+ }
+
+ cluster_offset = 0;
+
+ /* seek the the l2 offset in the l1 table */
+
+ l1_index = offset >> l1_bits;
+ if (l1_index >= s->l1_size)
+ goto out;
+
+ l2_offset = s->l1_table[l1_index];
+
+ /* seek the l2 table of the given l2 offset */
+
+ if (!l2_offset)
+ goto out;
+
+ /* load the l2 table in memory */
+
+ l2_offset &= ~QCOW_OFLAG_COPIED;
+ l2_table = l2_load(bs, l2_offset);
+ if (l2_table == NULL)
+ return 0;
+
+ /* find the cluster offset for the given disk offset */
+
+ l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
+ cluster_offset = be64_to_cpu(l2_table[l2_index]);
+ nb_clusters = size_to_clusters(s, nb_needed << 9);
+
+ if (!cluster_offset) {
+ /* how many empty clusters ? */
+ c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]);
+ } else {
+ /* how many allocated clusters ? */
+ c = count_contiguous_clusters(nb_clusters, s->cluster_size,
+ &l2_table[l2_index], 0, QCOW_OFLAG_COPIED);
+ }
+
+ nb_available = (c * s->cluster_sectors);
+out:
+ if (nb_available > nb_needed)
+ nb_available = nb_needed;
+
+ *num = nb_available - index_in_cluster;
+
+ return cluster_offset & ~QCOW_OFLAG_COPIED;
+}
+
+/*
+ * get_cluster_table
+ *
+ * for a given disk offset, load (and allocate if needed)
+ * the l2 table.
+ *
+ * the l2 table offset in the qcow2 file and the cluster index
+ * in the l2 table are given to the caller.
+ *
+ */
+
+static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
+ uint64_t **new_l2_table,
+ uint64_t *new_l2_offset,
+ int *new_l2_index)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l1_index, l2_index, ret;
+ uint64_t l2_offset, *l2_table;
+
+ /* seek the the l2 offset in the l1 table */
+
+ l1_index = offset >> (s->l2_bits + s->cluster_bits);
+ if (l1_index >= s->l1_size) {
+ ret = grow_l1_table(bs, l1_index + 1);
+ if (ret < 0)
+ return 0;
+ }
+ l2_offset = s->l1_table[l1_index];
+
+ /* seek the l2 table of the given l2 offset */
+
+ if (l2_offset & QCOW_OFLAG_COPIED) {
+ /* load the l2 table in memory */
+ l2_offset &= ~QCOW_OFLAG_COPIED;
+ l2_table = l2_load(bs, l2_offset);
+ if (l2_table == NULL)
+ return 0;
+ } else {
+ if (l2_offset)
+ free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
+ l2_table = l2_allocate(bs, l1_index);
+ if (l2_table == NULL)
+ return 0;
+ l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED;
+ }
+
+ /* find the cluster offset for the given disk offset */
+
+ l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
+
+ *new_l2_table = l2_table;
+ *new_l2_offset = l2_offset;
+ *new_l2_index = l2_index;
+
+ return 1;
+}
+
+/*
+ * alloc_compressed_cluster_offset
+ *
+ * For a given offset of the disk image, return cluster offset in
+ * qcow2 file.
+ *
+ * If the offset is not found, allocate a new compressed cluster.
+ *
+ * Return the cluster offset if successful,
+ * Return 0, otherwise.
+ *
+ */
+
+uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int compressed_size)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l2_index, ret;
+ uint64_t l2_offset, *l2_table, cluster_offset;
+ int nb_csectors;
+
+ ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
+ if (ret == 0)
+ return 0;
+
+ cluster_offset = be64_to_cpu(l2_table[l2_index]);
+ if (cluster_offset & QCOW_OFLAG_COPIED)
+ return cluster_offset & ~QCOW_OFLAG_COPIED;
+
+ if (cluster_offset)
+ free_any_clusters(bs, cluster_offset, 1);
+
+ cluster_offset = alloc_bytes(bs, compressed_size);
+ nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
+ (cluster_offset >> 9);
+
+ cluster_offset |= QCOW_OFLAG_COMPRESSED |
+ ((uint64_t)nb_csectors << s->csize_shift);
+
+ /* update L2 table */
+
+ /* compressed clusters never have the copied flag */
+
+ l2_table[l2_index] = cpu_to_be64(cluster_offset);
+ if (bdrv_pwrite(s->hd,
+ l2_offset + l2_index * sizeof(uint64_t),
+ l2_table + l2_index,
+ sizeof(uint64_t)) != sizeof(uint64_t))
+ return 0;
+
+ return cluster_offset;
+}
+
+int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
+ QCowL2Meta *m)
+{
+ BDRVQcowState *s = bs->opaque;
+ int i, j = 0, l2_index, ret;
+ uint64_t *old_cluster, start_sect, l2_offset, *l2_table;
+
+ if (m->nb_clusters == 0)
+ return 0;
+
+ old_cluster = qemu_malloc(m->nb_clusters * sizeof(uint64_t));
+
+ /* copy content of unmodified sectors */
+ start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9;
+ if (m->n_start) {
+ ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start);
+ if (ret < 0)
+ goto err;
+ }
+
+ if (m->nb_available & (s->cluster_sectors - 1)) {
+ uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1);
+ ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9),
+ m->nb_available - end, s->cluster_sectors);
+ if (ret < 0)
+ goto err;
+ }
+
+ ret = -EIO;
+ /* update L2 table */
+ if (!get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index))
+ goto err;
+
+ for (i = 0; i < m->nb_clusters; i++) {
+ /* if two concurrent writes happen to the same unallocated cluster
+ * each write allocates separate cluster and writes data concurrently.
+ * The first one to complete updates l2 table with pointer to its
+ * cluster the second one has to do RMW (which is done above by
+ * copy_sectors()), update l2 table with its cluster pointer and free
+ * old cluster. This is what this loop does */
+ if(l2_table[l2_index + i] != 0)
+ old_cluster[j++] = l2_table[l2_index + i];
+
+ l2_table[l2_index + i] = cpu_to_be64((cluster_offset +
+ (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);
+ }
+
+ if (bdrv_pwrite(s->hd, l2_offset + l2_index * sizeof(uint64_t),
+ l2_table + l2_index, m->nb_clusters * sizeof(uint64_t)) !=
+ m->nb_clusters * sizeof(uint64_t))
+ goto err;
+
+ for (i = 0; i < j; i++)
+ free_any_clusters(bs, be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED,
+ 1);
+
+ ret = 0;
+err:
+ qemu_free(old_cluster);
+ return ret;
+ }
+
+/*
+ * alloc_cluster_offset
+ *
+ * For a given offset of the disk image, return cluster offset in
+ * qcow2 file.
+ *
+ * If the offset is not found, allocate a new cluster.
+ *
+ * Return the cluster offset if successful,
+ * Return 0, otherwise.
+ *
+ */
+
+uint64_t alloc_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int n_start, int n_end,
+ int *num, QCowL2Meta *m)
+{
+ BDRVQcowState *s = bs->opaque;
+ int l2_index, ret;
+ uint64_t l2_offset, *l2_table, cluster_offset;
+ int nb_clusters, i = 0;
+
+ ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
+ if (ret == 0)
+ return 0;
+
+ nb_clusters = size_to_clusters(s, n_end << 9);
+
+ nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+
+ cluster_offset = be64_to_cpu(l2_table[l2_index]);
+
+ /* We keep all QCOW_OFLAG_COPIED clusters */
+
+ if (cluster_offset & QCOW_OFLAG_COPIED) {
+ nb_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size,
+ &l2_table[l2_index], 0, 0);
+
+ cluster_offset &= ~QCOW_OFLAG_COPIED;
+ m->nb_clusters = 0;
+
+ goto out;
+ }
+
+ /* for the moment, multiple compressed clusters are not managed */
+
+ if (cluster_offset & QCOW_OFLAG_COMPRESSED)
+ nb_clusters = 1;
+
+ /* how many available clusters ? */
+
+ while (i < nb_clusters) {
+ i += count_contiguous_clusters(nb_clusters - i, s->cluster_size,
+ &l2_table[l2_index], i, 0);
+
+ if(be64_to_cpu(l2_table[l2_index + i]))
+ break;
+
+ i += count_contiguous_free_clusters(nb_clusters - i,
+ &l2_table[l2_index + i]);
+
+ cluster_offset = be64_to_cpu(l2_table[l2_index + i]);
+
+ if ((cluster_offset & QCOW_OFLAG_COPIED) ||
+ (cluster_offset & QCOW_OFLAG_COMPRESSED))
+ break;
+ }
+ nb_clusters = i;
+
+ /* allocate a new cluster */
+
+ cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size);
+
+ /* save info needed for meta data update */
+ m->offset = offset;
+ m->n_start = n_start;
+ m->nb_clusters = nb_clusters;
+
+out:
+ m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end);
+
+ *num = m->nb_available - n_start;
+
+ return cluster_offset;
+}
+
+static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
+ const uint8_t *buf, int buf_size)
+{
+ z_stream strm1, *strm = &strm1;
+ int ret, out_len;
+
+ memset(strm, 0, sizeof(*strm));
+
+ strm->next_in = (uint8_t *)buf;
+ strm->avail_in = buf_size;
+ strm->next_out = out_buf;
+ strm->avail_out = out_buf_size;
+
+ ret = inflateInit2(strm, -12);
+ if (ret != Z_OK)
+ return -1;
+ ret = inflate(strm, Z_FINISH);
+ out_len = strm->next_out - out_buf;
+ if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
+ out_len != out_buf_size) {
+ inflateEnd(strm);
+ return -1;
+ }
+ inflateEnd(strm);
+ return 0;
+}
+
+int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
+{
+ int ret, csize, nb_csectors, sector_offset;
+ uint64_t coffset;
+
+ coffset = cluster_offset & s->cluster_offset_mask;
+ if (s->cluster_cache_offset != coffset) {
+ nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
+ sector_offset = coffset & 511;
+ csize = nb_csectors * 512 - sector_offset;
+ ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors);
+ if (ret < 0) {
+ return -1;
+ }
+ if (decompress_buffer(s->cluster_cache, s->cluster_size,
+ s->cluster_data + sector_offset, csize) < 0) {
+ return -1;
+ }
+ s->cluster_cache_offset = coffset;
+ }
+ return 0;
+}
update_refcount(bs, offset, size, -1);
}
+/*
+ * free_any_clusters
+ *
+ * free clusters according to its type: compressed or not
+ *
+ */
+
+void free_any_clusters(BlockDriverState *bs,
+ uint64_t cluster_offset, int nb_clusters)
+{
+ BDRVQcowState *s = bs->opaque;
+
+ /* free the cluster */
+
+ if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
+ int nb_csectors;
+ nb_csectors = ((cluster_offset >> s->csize_shift) &
+ s->csize_mask) + 1;
+ free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511,
+ nb_csectors * 512);
+ return;
+ }
+
+ free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits);
+
+ return;
+}
+
/*********************************************************/
} QCowSnapshotHeader;
-static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
-static int qcow_read(BlockDriverState *bs, int64_t sector_num,
- uint8_t *buf, int nb_sectors);
static int qcow_read_snapshots(BlockDriverState *bs);
static void qcow_free_snapshots(BlockDriverState *bs);
return 0;
}
-/* The crypt function is compatible with the linux cryptoloop
- algorithm for < 4 GB images. NOTE: out_buf == in_buf is
- supported */
-static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
- uint8_t *out_buf, const uint8_t *in_buf,
- int nb_sectors, int enc,
- const AES_KEY *key)
-{
- union {
- uint64_t ll[2];
- uint8_t b[16];
- } ivec;
- int i;
-
- for(i = 0; i < nb_sectors; i++) {
- ivec.ll[0] = cpu_to_le64(sector_num);
- ivec.ll[1] = 0;
- AES_cbc_encrypt(in_buf, out_buf, 512, key,
- ivec.b, enc);
- sector_num++;
- in_buf += 512;
- out_buf += 512;
- }
-}
-
-static int copy_sectors(BlockDriverState *bs, uint64_t start_sect,
- uint64_t cluster_offset, int n_start, int n_end)
-{
- BDRVQcowState *s = bs->opaque;
- int n, ret;
-
- n = n_end - n_start;
- if (n <= 0)
- return 0;
- ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n);
- if (ret < 0)
- return ret;
- if (s->crypt_method) {
- encrypt_sectors(s, start_sect + n_start,
- s->cluster_data,
- s->cluster_data, n, 1,
- &s->aes_encrypt_key);
- }
- ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start,
- s->cluster_data, n);
- if (ret < 0)
- return ret;
- return 0;
-}
-
-void l2_cache_reset(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
-
- memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
- memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
- memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
-}
-
-static inline int l2_cache_new_entry(BlockDriverState *bs)
-{
- BDRVQcowState *s = bs->opaque;
- uint32_t min_count;
- int min_index, i;
-
- /* find a new entry in the least used one */
- min_index = 0;
- min_count = 0xffffffff;
- for(i = 0; i < L2_CACHE_SIZE; i++) {
- if (s->l2_cache_counts[i] < min_count) {
- min_count = s->l2_cache_counts[i];
- min_index = i;
- }
- }
- return min_index;
-}
-
static int64_t align_offset(int64_t offset, int n)
{
offset = (offset + n - 1) & ~(n - 1);
return offset;
}
-static int grow_l1_table(BlockDriverState *bs, int min_size)
-{
- BDRVQcowState *s = bs->opaque;
- int new_l1_size, new_l1_size2, ret, i;
- uint64_t *new_l1_table;
- uint64_t new_l1_table_offset;
- uint8_t data[12];
-
- new_l1_size = s->l1_size;
- if (min_size <= new_l1_size)
- return 0;
- while (min_size > new_l1_size) {
- new_l1_size = (new_l1_size * 3 + 1) / 2;
- }
-#ifdef DEBUG_ALLOC2
- printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size);
-#endif
-
- new_l1_size2 = sizeof(uint64_t) * new_l1_size;
- new_l1_table = qemu_mallocz(new_l1_size2);
- memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
-
- /* write new table (align to cluster) */
- new_l1_table_offset = alloc_clusters(bs, new_l1_size2);
-
- for(i = 0; i < s->l1_size; i++)
- new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
- ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2);
- if (ret != new_l1_size2)
- goto fail;
- for(i = 0; i < s->l1_size; i++)
- new_l1_table[i] = be64_to_cpu(new_l1_table[i]);
-
- /* set new table */
- cpu_to_be32w((uint32_t*)data, new_l1_size);
- cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset);
- if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data,
- sizeof(data)) != sizeof(data))
- goto fail;
- qemu_free(s->l1_table);
- free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
- s->l1_table_offset = new_l1_table_offset;
- s->l1_table = new_l1_table;
- s->l1_size = new_l1_size;
- return 0;
- fail:
- qemu_free(s->l1_table);
- return -EIO;
-}
-
-/*
- * seek_l2_table
- *
- * seek l2_offset in the l2_cache table
- * if not found, return NULL,
- * if found,
- * increments the l2 cache hit count of the entry,
- * if counter overflow, divide by two all counters
- * return the pointer to the l2 cache entry
- *
- */
-
-static uint64_t *seek_l2_table(BDRVQcowState *s, uint64_t l2_offset)
-{
- int i, j;
-
- for(i = 0; i < L2_CACHE_SIZE; i++) {
- if (l2_offset == s->l2_cache_offsets[i]) {
- /* increment the hit count */
- if (++s->l2_cache_counts[i] == 0xffffffff) {
- for(j = 0; j < L2_CACHE_SIZE; j++) {
- s->l2_cache_counts[j] >>= 1;
- }
- }
- return s->l2_cache + (i << s->l2_bits);
- }
- }
- return NULL;
-}
-
-/*
- * l2_load
- *
- * Loads a L2 table into memory. If the table is in the cache, the cache
- * is used; otherwise the L2 table is loaded from the image file.
- *
- * Returns a pointer to the L2 table on success, or NULL if the read from
- * the image file failed.
- */
-
-static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset)
-{
- BDRVQcowState *s = bs->opaque;
- int min_index;
- uint64_t *l2_table;
-
- /* seek if the table for the given offset is in the cache */
-
- l2_table = seek_l2_table(s, l2_offset);
- if (l2_table != NULL)
- return l2_table;
-
- /* not found: load a new entry in the least used one */
-
- min_index = l2_cache_new_entry(bs);
- l2_table = s->l2_cache + (min_index << s->l2_bits);
- if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
- s->l2_size * sizeof(uint64_t))
- return NULL;
- s->l2_cache_offsets[min_index] = l2_offset;
- s->l2_cache_counts[min_index] = 1;
-
- return l2_table;
-}
-
-/*
- * l2_allocate
- *
- * Allocate a new l2 entry in the file. If l1_index points to an already
- * used entry in the L2 table (i.e. we are doing a copy on write for the L2
- * table) copy the contents of the old L2 table into the newly allocated one.
- * Otherwise the new table is initialized with zeros.
- *
- */
-
-static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index)
-{
- BDRVQcowState *s = bs->opaque;
- int min_index;
- uint64_t old_l2_offset, tmp;
- uint64_t *l2_table, l2_offset;
-
- old_l2_offset = s->l1_table[l1_index];
-
- /* allocate a new l2 entry */
-
- l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
-
- /* update the L1 entry */
-
- s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED;
-
- tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED);
- if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp),
- &tmp, sizeof(tmp)) != sizeof(tmp))
- return NULL;
-
- /* allocate a new entry in the l2 cache */
-
- min_index = l2_cache_new_entry(bs);
- l2_table = s->l2_cache + (min_index << s->l2_bits);
-
- if (old_l2_offset == 0) {
- /* if there was no old l2 table, clear the new table */
- memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
- } else {
- /* if there was an old l2 table, read it from the disk */
- if (bdrv_pread(s->hd, old_l2_offset,
- l2_table, s->l2_size * sizeof(uint64_t)) !=
- s->l2_size * sizeof(uint64_t))
- return NULL;
- }
- /* write the l2 table to the file */
- if (bdrv_pwrite(s->hd, l2_offset,
- l2_table, s->l2_size * sizeof(uint64_t)) !=
- s->l2_size * sizeof(uint64_t))
- return NULL;
-
- /* update the l2 cache entry */
-
- s->l2_cache_offsets[min_index] = l2_offset;
- s->l2_cache_counts[min_index] = 1;
-
- return l2_table;
-}
-
-static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size,
- uint64_t *l2_table, uint64_t start, uint64_t mask)
-{
- int i;
- uint64_t offset = be64_to_cpu(l2_table[0]) & ~mask;
-
- if (!offset)
- return 0;
-
- for (i = start; i < start + nb_clusters; i++)
- if (offset + i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask))
- break;
-
- return (i - start);
-}
-
-static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table)
-{
- int i = 0;
-
- while(nb_clusters-- && l2_table[i] == 0)
- i++;
-
- return i;
-}
-
-/*
- * get_cluster_offset
- *
- * For a given offset of the disk image, return cluster offset in
- * qcow2 file.
- *
- * on entry, *num is the number of contiguous clusters we'd like to
- * access following offset.
- *
- * on exit, *num is the number of contiguous clusters we can read.
- *
- * Return 1, if the offset is found
- * Return 0, otherwise.
- *
- */
-
-static uint64_t get_cluster_offset(BlockDriverState *bs,
- uint64_t offset, int *num)
-{
- BDRVQcowState *s = bs->opaque;
- int l1_index, l2_index;
- uint64_t l2_offset, *l2_table, cluster_offset;
- int l1_bits, c;
- int index_in_cluster, nb_available, nb_needed, nb_clusters;
-
- index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1);
- nb_needed = *num + index_in_cluster;
-
- l1_bits = s->l2_bits + s->cluster_bits;
-
- /* compute how many bytes there are between the offset and
- * the end of the l1 entry
- */
-
- nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1));
-
- /* compute the number of available sectors */
-
- nb_available = (nb_available >> 9) + index_in_cluster;
-
- if (nb_needed > nb_available) {
- nb_needed = nb_available;
- }
-
- cluster_offset = 0;
-
- /* seek the the l2 offset in the l1 table */
-
- l1_index = offset >> l1_bits;
- if (l1_index >= s->l1_size)
- goto out;
-
- l2_offset = s->l1_table[l1_index];
-
- /* seek the l2 table of the given l2 offset */
-
- if (!l2_offset)
- goto out;
-
- /* load the l2 table in memory */
-
- l2_offset &= ~QCOW_OFLAG_COPIED;
- l2_table = l2_load(bs, l2_offset);
- if (l2_table == NULL)
- return 0;
-
- /* find the cluster offset for the given disk offset */
-
- l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
- cluster_offset = be64_to_cpu(l2_table[l2_index]);
- nb_clusters = size_to_clusters(s, nb_needed << 9);
-
- if (!cluster_offset) {
- /* how many empty clusters ? */
- c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]);
- } else {
- /* how many allocated clusters ? */
- c = count_contiguous_clusters(nb_clusters, s->cluster_size,
- &l2_table[l2_index], 0, QCOW_OFLAG_COPIED);
- }
-
- nb_available = (c * s->cluster_sectors);
-out:
- if (nb_available > nb_needed)
- nb_available = nb_needed;
-
- *num = nb_available - index_in_cluster;
-
- return cluster_offset & ~QCOW_OFLAG_COPIED;
-}
-
-/*
- * free_any_clusters
- *
- * free clusters according to its type: compressed or not
- *
- */
-
-static void free_any_clusters(BlockDriverState *bs,
- uint64_t cluster_offset, int nb_clusters)
-{
- BDRVQcowState *s = bs->opaque;
-
- /* free the cluster */
-
- if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
- int nb_csectors;
- nb_csectors = ((cluster_offset >> s->csize_shift) &
- s->csize_mask) + 1;
- free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511,
- nb_csectors * 512);
- return;
- }
-
- free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits);
-
- return;
-}
-
-/*
- * get_cluster_table
- *
- * for a given disk offset, load (and allocate if needed)
- * the l2 table.
- *
- * the l2 table offset in the qcow2 file and the cluster index
- * in the l2 table are given to the caller.
- *
- */
-
-static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
- uint64_t **new_l2_table,
- uint64_t *new_l2_offset,
- int *new_l2_index)
-{
- BDRVQcowState *s = bs->opaque;
- int l1_index, l2_index, ret;
- uint64_t l2_offset, *l2_table;
-
- /* seek the the l2 offset in the l1 table */
-
- l1_index = offset >> (s->l2_bits + s->cluster_bits);
- if (l1_index >= s->l1_size) {
- ret = grow_l1_table(bs, l1_index + 1);
- if (ret < 0)
- return 0;
- }
- l2_offset = s->l1_table[l1_index];
-
- /* seek the l2 table of the given l2 offset */
-
- if (l2_offset & QCOW_OFLAG_COPIED) {
- /* load the l2 table in memory */
- l2_offset &= ~QCOW_OFLAG_COPIED;
- l2_table = l2_load(bs, l2_offset);
- if (l2_table == NULL)
- return 0;
- } else {
- if (l2_offset)
- free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
- l2_table = l2_allocate(bs, l1_index);
- if (l2_table == NULL)
- return 0;
- l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED;
- }
-
- /* find the cluster offset for the given disk offset */
-
- l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
-
- *new_l2_table = l2_table;
- *new_l2_offset = l2_offset;
- *new_l2_index = l2_index;
-
- return 1;
-}
-
-/*
- * alloc_compressed_cluster_offset
- *
- * For a given offset of the disk image, return cluster offset in
- * qcow2 file.
- *
- * If the offset is not found, allocate a new compressed cluster.
- *
- * Return the cluster offset if successful,
- * Return 0, otherwise.
- *
- */
-
-static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
- uint64_t offset,
- int compressed_size)
-{
- BDRVQcowState *s = bs->opaque;
- int l2_index, ret;
- uint64_t l2_offset, *l2_table, cluster_offset;
- int nb_csectors;
-
- ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
- if (ret == 0)
- return 0;
-
- cluster_offset = be64_to_cpu(l2_table[l2_index]);
- if (cluster_offset & QCOW_OFLAG_COPIED)
- return cluster_offset & ~QCOW_OFLAG_COPIED;
-
- if (cluster_offset)
- free_any_clusters(bs, cluster_offset, 1);
-
- cluster_offset = alloc_bytes(bs, compressed_size);
- nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
- (cluster_offset >> 9);
-
- cluster_offset |= QCOW_OFLAG_COMPRESSED |
- ((uint64_t)nb_csectors << s->csize_shift);
-
- /* update L2 table */
-
- /* compressed clusters never have the copied flag */
-
- l2_table[l2_index] = cpu_to_be64(cluster_offset);
- if (bdrv_pwrite(s->hd,
- l2_offset + l2_index * sizeof(uint64_t),
- l2_table + l2_index,
- sizeof(uint64_t)) != sizeof(uint64_t))
- return 0;
-
- return cluster_offset;
-}
-
-typedef struct QCowL2Meta
-{
- uint64_t offset;
- int n_start;
- int nb_available;
- int nb_clusters;
-} QCowL2Meta;
-
-static int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
- QCowL2Meta *m)
-{
- BDRVQcowState *s = bs->opaque;
- int i, j = 0, l2_index, ret;
- uint64_t *old_cluster, start_sect, l2_offset, *l2_table;
-
- if (m->nb_clusters == 0)
- return 0;
-
- old_cluster = qemu_malloc(m->nb_clusters * sizeof(uint64_t));
-
- /* copy content of unmodified sectors */
- start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9;
- if (m->n_start) {
- ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start);
- if (ret < 0)
- goto err;
- }
-
- if (m->nb_available & (s->cluster_sectors - 1)) {
- uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1);
- ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9),
- m->nb_available - end, s->cluster_sectors);
- if (ret < 0)
- goto err;
- }
-
- ret = -EIO;
- /* update L2 table */
- if (!get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index))
- goto err;
-
- for (i = 0; i < m->nb_clusters; i++) {
- /* if two concurrent writes happen to the same unallocated cluster
- * each write allocates separate cluster and writes data concurrently.
- * The first one to complete updates l2 table with pointer to its
- * cluster the second one has to do RMW (which is done above by
- * copy_sectors()), update l2 table with its cluster pointer and free
- * old cluster. This is what this loop does */
- if(l2_table[l2_index + i] != 0)
- old_cluster[j++] = l2_table[l2_index + i];
-
- l2_table[l2_index + i] = cpu_to_be64((cluster_offset +
- (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);
- }
-
- if (bdrv_pwrite(s->hd, l2_offset + l2_index * sizeof(uint64_t),
- l2_table + l2_index, m->nb_clusters * sizeof(uint64_t)) !=
- m->nb_clusters * sizeof(uint64_t))
- goto err;
-
- for (i = 0; i < j; i++)
- free_any_clusters(bs, be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED,
- 1);
-
- ret = 0;
-err:
- qemu_free(old_cluster);
- return ret;
- }
-
-/*
- * alloc_cluster_offset
- *
- * For a given offset of the disk image, return cluster offset in
- * qcow2 file.
- *
- * If the offset is not found, allocate a new cluster.
- *
- * Return the cluster offset if successful,
- * Return 0, otherwise.
- *
- */
-
-static uint64_t alloc_cluster_offset(BlockDriverState *bs,
- uint64_t offset,
- int n_start, int n_end,
- int *num, QCowL2Meta *m)
-{
- BDRVQcowState *s = bs->opaque;
- int l2_index, ret;
- uint64_t l2_offset, *l2_table, cluster_offset;
- int nb_clusters, i = 0;
-
- ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
- if (ret == 0)
- return 0;
-
- nb_clusters = size_to_clusters(s, n_end << 9);
-
- nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
-
- cluster_offset = be64_to_cpu(l2_table[l2_index]);
-
- /* We keep all QCOW_OFLAG_COPIED clusters */
-
- if (cluster_offset & QCOW_OFLAG_COPIED) {
- nb_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size,
- &l2_table[l2_index], 0, 0);
-
- cluster_offset &= ~QCOW_OFLAG_COPIED;
- m->nb_clusters = 0;
-
- goto out;
- }
-
- /* for the moment, multiple compressed clusters are not managed */
-
- if (cluster_offset & QCOW_OFLAG_COMPRESSED)
- nb_clusters = 1;
-
- /* how many available clusters ? */
-
- while (i < nb_clusters) {
- i += count_contiguous_clusters(nb_clusters - i, s->cluster_size,
- &l2_table[l2_index], i, 0);
-
- if(be64_to_cpu(l2_table[l2_index + i]))
- break;
-
- i += count_contiguous_free_clusters(nb_clusters - i,
- &l2_table[l2_index + i]);
-
- cluster_offset = be64_to_cpu(l2_table[l2_index + i]);
-
- if ((cluster_offset & QCOW_OFLAG_COPIED) ||
- (cluster_offset & QCOW_OFLAG_COMPRESSED))
- break;
- }
- nb_clusters = i;
-
- /* allocate a new cluster */
-
- cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size);
-
- /* save info needed for meta data update */
- m->offset = offset;
- m->n_start = n_start;
- m->nb_clusters = nb_clusters;
-
-out:
- m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end);
-
- *num = m->nb_available - n_start;
-
- return cluster_offset;
-}
-
static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, int *pnum)
{
return (cluster_offset != 0);
}
-static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
- const uint8_t *buf, int buf_size)
-{
- z_stream strm1, *strm = &strm1;
- int ret, out_len;
-
- memset(strm, 0, sizeof(*strm));
-
- strm->next_in = (uint8_t *)buf;
- strm->avail_in = buf_size;
- strm->next_out = out_buf;
- strm->avail_out = out_buf_size;
-
- ret = inflateInit2(strm, -12);
- if (ret != Z_OK)
- return -1;
- ret = inflate(strm, Z_FINISH);
- out_len = strm->next_out - out_buf;
- if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
- out_len != out_buf_size) {
- inflateEnd(strm);
- return -1;
- }
- inflateEnd(strm);
- return 0;
-}
-
-static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset)
-{
- int ret, csize, nb_csectors, sector_offset;
- uint64_t coffset;
-
- coffset = cluster_offset & s->cluster_offset_mask;
- if (s->cluster_cache_offset != coffset) {
- nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
- sector_offset = coffset & 511;
- csize = nb_csectors * 512 - sector_offset;
- ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors);
- if (ret < 0) {
- return -1;
- }
- if (decompress_buffer(s->cluster_cache, s->cluster_size,
- s->cluster_data + sector_offset, csize) < 0) {
- return -1;
- }
- s->cluster_cache_offset = coffset;
- }
- return 0;
-}
-
/* handle reading after the end of the backing file */
-static int backing_read1(BlockDriverState *bs,
- int64_t sector_num, uint8_t *buf, int nb_sectors)
+int backing_read1(BlockDriverState *bs,
+ int64_t sector_num, uint8_t *buf, int nb_sectors)
{
int n1;
if ((sector_num + nb_sectors) <= bs->total_sectors)
return n1;
}
-static int qcow_read(BlockDriverState *bs, int64_t sector_num,
- uint8_t *buf, int nb_sectors)
-{
- BDRVQcowState *s = bs->opaque;
- int ret, index_in_cluster, n, n1;
- uint64_t cluster_offset;
-
- while (nb_sectors > 0) {
- n = nb_sectors;
- cluster_offset = get_cluster_offset(bs, sector_num << 9, &n);
- index_in_cluster = sector_num & (s->cluster_sectors - 1);
- if (!cluster_offset) {
- if (bs->backing_hd) {
- /* read from the base image */
- n1 = backing_read1(bs->backing_hd, sector_num, buf, n);
- if (n1 > 0) {
- ret = bdrv_read(bs->backing_hd, sector_num, buf, n1);
- if (ret < 0)
- return -1;
- }
- } else {
- memset(buf, 0, 512 * n);
- }
- } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
- if (decompress_cluster(s, cluster_offset) < 0)
- return -1;
- memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n);
- } else {
- ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512);
- if (ret != n * 512)
- return -1;
- if (s->crypt_method) {
- encrypt_sectors(s, sector_num, buf, buf, n, 0,
- &s->aes_decrypt_key);
- }
- }
- nb_sectors -= n;
- sector_num += n;
- buf += n * 512;
- }
- return 0;
-}
-
typedef struct QCowAIOCB {
BlockDriverAIOCB common;
int64_t sector_num;
int64_t refcount_block_offset;
} QCowCreateState;
-static int size_to_clusters(BDRVQcowState *s, int64_t size)
+/* XXX This could be private for qcow2-cluster.c */
+typedef struct QCowL2Meta
+{
+ uint64_t offset;
+ int n_start;
+ int nb_available;
+ int nb_clusters;
+} QCowL2Meta;
+
+static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
{
return (size + (s->cluster_size - 1)) >> s->cluster_bits;
}
/* qcow2.c functions */
void l2_cache_reset(BlockDriverState *bs);
+int backing_read1(BlockDriverState *bs,
+ int64_t sector_num, uint8_t *buf, int nb_sectors);
/* qcow2-refcount.c functions */
int refcount_init(BlockDriverState *bs);
int64_t alloc_clusters(BlockDriverState *bs, int64_t size);
int64_t alloc_bytes(BlockDriverState *bs, int size);
void free_clusters(BlockDriverState *bs,
- int64_t offset, int64_t size);
+ int64_t offset, int64_t size);
+void free_any_clusters(BlockDriverState *bs,
+ uint64_t cluster_offset, int nb_clusters);
void create_refcount_update(QCowCreateState *s, int64_t offset, int64_t size);
int update_snapshot_refcount(BlockDriverState *bs,
int check_refcounts(BlockDriverState *bs);
+/* qcow2-cluster.c functions */
+int grow_l1_table(BlockDriverState *bs, int min_size);
+int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset);
+void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+ uint8_t *out_buf, const uint8_t *in_buf,
+ int nb_sectors, int enc,
+ const AES_KEY *key);
+
+uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int *num);
+uint64_t alloc_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int n_start, int n_end,
+ int *num, QCowL2Meta *m);
+uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs,
+ uint64_t offset,
+ int compressed_size);
+
+int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
+ QCowL2Meta *m);
+
#endif
projects / sdk / emulator / qemu.git / commitdiff