#include "qemu/osdep.h"
#include <zlib.h>
+#include "qapi/error.h"
#include "qemu-common.h"
#include "block/block_int.h"
#include "block/qcow2.h"
new_l1_size2 = sizeof(uint64_t) * new_l1_size;
new_l1_table = qemu_try_blockalign(bs->file->bs,
- align_offset(new_l1_size2, 512));
+ ROUND_UP(new_l1_size2, 512));
if (new_l1_table == NULL) {
return -ENOMEM;
}
- memset(new_l1_table, 0, align_offset(new_l1_size2, 512));
+ memset(new_l1_table, 0, ROUND_UP(new_l1_size2, 512));
if (s->l1_size) {
memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
}
/*
- * Checks how many clusters in a given L2 table are contiguous in the image
+ * Checks how many clusters in a given L2 slice are contiguous in the image
* file. As soon as one of the flags in the bitmask stop_flags changes compared
* to the first cluster, the search is stopped and the cluster is not counted
* as contiguous. (This allows it, for example, to stop at the first compressed
* cluster which may require a different handling)
*/
static int count_contiguous_clusters(int nb_clusters, int cluster_size,
- uint64_t *l2_table, uint64_t stop_flags)
+ uint64_t *l2_slice, uint64_t stop_flags)
{
int i;
QCow2ClusterType first_cluster_type;
uint64_t mask = stop_flags | L2E_OFFSET_MASK | QCOW_OFLAG_COMPRESSED;
- uint64_t first_entry = be64_to_cpu(l2_table[0]);
+ uint64_t first_entry = be64_to_cpu(l2_slice[0]);
uint64_t offset = first_entry & mask;
if (!offset) {
first_cluster_type == QCOW2_CLUSTER_ZERO_ALLOC);
for (i = 0; i < nb_clusters; i++) {
- uint64_t l2_entry = be64_to_cpu(l2_table[i]) & mask;
+ uint64_t l2_entry = be64_to_cpu(l2_slice[i]) & mask;
if (offset + (uint64_t) i * cluster_size != l2_entry) {
break;
}
/*
* Checks how many consecutive unallocated clusters in a given L2
- * table have the same cluster type.
+ * slice have the same cluster type.
*/
static int count_contiguous_clusters_unallocated(int nb_clusters,
- uint64_t *l2_table,
+ uint64_t *l2_slice,
QCow2ClusterType wanted_type)
{
int i;
assert(wanted_type == QCOW2_CLUSTER_ZERO_PLAIN ||
wanted_type == QCOW2_CLUSTER_UNALLOCATED);
for (i = 0; i < nb_clusters; i++) {
- uint64_t entry = be64_to_cpu(l2_table[i]);
+ uint64_t entry = be64_to_cpu(l2_slice[i]);
QCow2ClusterType type = qcow2_get_cluster_type(entry);
if (type != wanted_type) {
{
BDRVQcow2State *s = bs->opaque;
int l2_index, ret;
- uint64_t *l2_table;
+ uint64_t *l2_slice;
int64_t cluster_offset;
int nb_csectors;
- ret = get_cluster_table(bs, offset, &l2_table, &l2_index);
+ ret = get_cluster_table(bs, offset, &l2_slice, &l2_index);
if (ret < 0) {
return 0;
}
/* Compression can't overwrite anything. Fail if the cluster was already
* allocated. */
- cluster_offset = be64_to_cpu(l2_table[l2_index]);
+ cluster_offset = be64_to_cpu(l2_slice[l2_index]);
if (cluster_offset & L2E_OFFSET_MASK) {
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
return 0;
}
cluster_offset = qcow2_alloc_bytes(bs, compressed_size);
if (cluster_offset < 0) {
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
return 0;
}
/* compressed clusters never have the copied flag */
BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE_COMPRESSED);
- qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
- l2_table[l2_index] = cpu_to_be64(cluster_offset);
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
+ qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_slice);
+ l2_slice[l2_index] = cpu_to_be64(cluster_offset);
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
return cluster_offset;
}
* which must copy from the backing file)
*/
static int count_cow_clusters(BDRVQcow2State *s, int nb_clusters,
- uint64_t *l2_table, int l2_index)
+ uint64_t *l2_slice, int l2_index)
{
int i;
for (i = 0; i < nb_clusters; i++) {
- uint64_t l2_entry = be64_to_cpu(l2_table[l2_index + i]);
+ uint64_t l2_entry = be64_to_cpu(l2_slice[l2_index + i]);
QCow2ClusterType cluster_type = qcow2_get_cluster_type(l2_entry);
switch(cluster_type) {
{
BDRVQcow2State *s = bs->opaque;
int l2_index;
- uint64_t *l2_table;
+ uint64_t *l2_slice;
uint64_t entry;
uint64_t nb_clusters;
int ret;
assert(*bytes > 0);
/*
- * Calculate the number of clusters to look for. We stop at L2 table
+ * Calculate the number of clusters to look for. We stop at L2 slice
* boundaries to keep things simple.
*/
nb_clusters =
size_to_clusters(s, offset_into_cluster(s, guest_offset) + *bytes);
- l2_index = offset_to_l2_index(s, guest_offset);
- nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+ l2_index = offset_to_l2_slice_index(s, guest_offset);
+ nb_clusters = MIN(nb_clusters, s->l2_slice_size - l2_index);
assert(nb_clusters <= INT_MAX);
/* Find L2 entry for the first involved cluster */
- ret = get_cluster_table(bs, guest_offset, &l2_table, &l2_index);
+ ret = get_cluster_table(bs, guest_offset, &l2_slice, &l2_index);
if (ret < 0) {
return ret;
}
- entry = be64_to_cpu(l2_table[l2_index]);
+ entry = be64_to_cpu(l2_slice[l2_index]);
/* For the moment, overwrite compressed clusters one by one */
if (entry & QCOW_OFLAG_COMPRESSED) {
nb_clusters = 1;
} else {
- nb_clusters = count_cow_clusters(s, nb_clusters, l2_table, l2_index);
+ nb_clusters = count_cow_clusters(s, nb_clusters, l2_slice, l2_index);
}
/* This function is only called when there were no non-COW clusters, so if
* nb_clusters already to a range of COW clusters */
preallocated_nb_clusters =
count_contiguous_clusters(nb_clusters, s->cluster_size,
- &l2_table[l2_index], QCOW_OFLAG_COPIED);
+ &l2_slice[l2_index], QCOW_OFLAG_COPIED);
assert(preallocated_nb_clusters > 0);
nb_clusters = preallocated_nb_clusters;
keep_old_clusters = true;
}
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
if (!alloc_cluster_offset) {
/* Allocate, if necessary at a given offset in the image file */
/*
* This discards as many clusters of nb_clusters as possible at once (i.e.
- * all clusters in the same L2 table) and returns the number of discarded
+ * all clusters in the same L2 slice) and returns the number of discarded
* clusters.
*/
-static int discard_single_l2(BlockDriverState *bs, uint64_t offset,
- uint64_t nb_clusters, enum qcow2_discard_type type,
- bool full_discard)
+static int discard_in_l2_slice(BlockDriverState *bs, uint64_t offset,
+ uint64_t nb_clusters,
+ enum qcow2_discard_type type, bool full_discard)
{
BDRVQcow2State *s = bs->opaque;
- uint64_t *l2_table;
+ uint64_t *l2_slice;
int l2_index;
int ret;
int i;
- ret = get_cluster_table(bs, offset, &l2_table, &l2_index);
+ ret = get_cluster_table(bs, offset, &l2_slice, &l2_index);
if (ret < 0) {
return ret;
}
- /* Limit nb_clusters to one L2 table */
- nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+ /* Limit nb_clusters to one L2 slice */
+ nb_clusters = MIN(nb_clusters, s->l2_slice_size - l2_index);
assert(nb_clusters <= INT_MAX);
for (i = 0; i < nb_clusters; i++) {
uint64_t old_l2_entry;
- old_l2_entry = be64_to_cpu(l2_table[l2_index + i]);
+ old_l2_entry = be64_to_cpu(l2_slice[l2_index + i]);
/*
* If full_discard is false, make sure that a discarded area reads back
}
/* First remove L2 entries */
- qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+ qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_slice);
if (!full_discard && s->qcow_version >= 3) {
- l2_table[l2_index + i] = cpu_to_be64(QCOW_OFLAG_ZERO);
+ l2_slice[l2_index + i] = cpu_to_be64(QCOW_OFLAG_ZERO);
} else {
- l2_table[l2_index + i] = cpu_to_be64(0);
+ l2_slice[l2_index + i] = cpu_to_be64(0);
}
/* Then decrease the refcount */
qcow2_free_any_clusters(bs, old_l2_entry, 1, type);
}
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
return nb_clusters;
}
s->cache_discards = true;
- /* Each L2 table is handled by its own loop iteration */
+ /* Each L2 slice is handled by its own loop iteration */
while (nb_clusters > 0) {
- cleared = discard_single_l2(bs, offset, nb_clusters, type,
- full_discard);
+ cleared = discard_in_l2_slice(bs, offset, nb_clusters, type,
+ full_discard);
if (cleared < 0) {
ret = cleared;
goto fail;
/*
* This zeroes as many clusters of nb_clusters as possible at once (i.e.
- * all clusters in the same L2 table) and returns the number of zeroed
+ * all clusters in the same L2 slice) and returns the number of zeroed
* clusters.
*/
-static int zero_single_l2(BlockDriverState *bs, uint64_t offset,
- uint64_t nb_clusters, int flags)
+static int zero_in_l2_slice(BlockDriverState *bs, uint64_t offset,
+ uint64_t nb_clusters, int flags)
{
BDRVQcow2State *s = bs->opaque;
- uint64_t *l2_table;
+ uint64_t *l2_slice;
int l2_index;
int ret;
int i;
bool unmap = !!(flags & BDRV_REQ_MAY_UNMAP);
- ret = get_cluster_table(bs, offset, &l2_table, &l2_index);
+ ret = get_cluster_table(bs, offset, &l2_slice, &l2_index);
if (ret < 0) {
return ret;
}
- /* Limit nb_clusters to one L2 table */
- nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+ /* Limit nb_clusters to one L2 slice */
+ nb_clusters = MIN(nb_clusters, s->l2_slice_size - l2_index);
assert(nb_clusters <= INT_MAX);
for (i = 0; i < nb_clusters; i++) {
uint64_t old_offset;
QCow2ClusterType cluster_type;
- old_offset = be64_to_cpu(l2_table[l2_index + i]);
+ old_offset = be64_to_cpu(l2_slice[l2_index + i]);
/*
* Minimize L2 changes if the cluster already reads back as
continue;
}
- qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+ qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_slice);
if (cluster_type == QCOW2_CLUSTER_COMPRESSED || unmap) {
- l2_table[l2_index + i] = cpu_to_be64(QCOW_OFLAG_ZERO);
+ l2_slice[l2_index + i] = cpu_to_be64(QCOW_OFLAG_ZERO);
qcow2_free_any_clusters(bs, old_offset, 1, QCOW2_DISCARD_REQUEST);
} else {
- l2_table[l2_index + i] |= cpu_to_be64(QCOW_OFLAG_ZERO);
+ l2_slice[l2_index + i] |= cpu_to_be64(QCOW_OFLAG_ZERO);
}
}
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
return nb_clusters;
}
return -ENOTSUP;
}
- /* Each L2 table is handled by its own loop iteration */
+ /* Each L2 slice is handled by its own loop iteration */
nb_clusters = size_to_clusters(s, bytes);
s->cache_discards = true;
while (nb_clusters > 0) {
- cleared = zero_single_l2(bs, offset, nb_clusters, flags);
+ cleared = zero_in_l2_slice(bs, offset, nb_clusters, flags);
if (cleared < 0) {
ret = cleared;
goto fail;
{
BDRVQcow2State *s = bs->opaque;
bool is_active_l1 = (l1_table == s->l1_table);
- uint64_t *l2_table = NULL;
+ uint64_t *l2_slice = NULL;
+ unsigned slice, slice_size2, n_slices;
int ret;
int i, j;
+ slice_size2 = s->l2_slice_size * sizeof(uint64_t);
+ n_slices = s->cluster_size / slice_size2;
+
if (!is_active_l1) {
/* inactive L2 tables require a buffer to be stored in when loading
* them from disk */
- l2_table = qemu_try_blockalign(bs->file->bs, s->cluster_size);
- if (l2_table == NULL) {
+ l2_slice = qemu_try_blockalign(bs->file->bs, slice_size2);
+ if (l2_slice == NULL) {
return -ENOMEM;
}
}
for (i = 0; i < l1_size; i++) {
uint64_t l2_offset = l1_table[i] & L1E_OFFSET_MASK;
- bool l2_dirty = false;
uint64_t l2_refcount;
if (!l2_offset) {
goto fail;
}
- if (is_active_l1) {
- /* get active L2 tables from cache */
- ret = qcow2_cache_get(bs, s->l2_table_cache, l2_offset,
- (void **)&l2_table);
- } else {
- /* load inactive L2 tables from disk */
- ret = bdrv_read(bs->file, l2_offset / BDRV_SECTOR_SIZE,
- (void *)l2_table, s->cluster_sectors);
- }
- if (ret < 0) {
- goto fail;
- }
-
ret = qcow2_get_refcount(bs, l2_offset >> s->cluster_bits,
&l2_refcount);
if (ret < 0) {
goto fail;
}
- for (j = 0; j < s->l2_size; j++) {
- uint64_t l2_entry = be64_to_cpu(l2_table[j]);
- int64_t offset = l2_entry & L2E_OFFSET_MASK;
- QCow2ClusterType cluster_type = qcow2_get_cluster_type(l2_entry);
-
- if (cluster_type != QCOW2_CLUSTER_ZERO_PLAIN &&
- cluster_type != QCOW2_CLUSTER_ZERO_ALLOC) {
- continue;
+ for (slice = 0; slice < n_slices; slice++) {
+ uint64_t slice_offset = l2_offset + slice * slice_size2;
+ bool l2_dirty = false;
+ if (is_active_l1) {
+ /* get active L2 tables from cache */
+ ret = qcow2_cache_get(bs, s->l2_table_cache, slice_offset,
+ (void **)&l2_slice);
+ } else {
+ /* load inactive L2 tables from disk */
+ ret = bdrv_pread(bs->file, slice_offset, l2_slice, slice_size2);
+ }
+ if (ret < 0) {
+ goto fail;
}
- if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
- if (!bs->backing) {
- /* not backed; therefore we can simply deallocate the
- * cluster */
- l2_table[j] = 0;
- l2_dirty = true;
+ for (j = 0; j < s->l2_slice_size; j++) {
+ uint64_t l2_entry = be64_to_cpu(l2_slice[j]);
+ int64_t offset = l2_entry & L2E_OFFSET_MASK;
+ QCow2ClusterType cluster_type =
+ qcow2_get_cluster_type(l2_entry);
+
+ if (cluster_type != QCOW2_CLUSTER_ZERO_PLAIN &&
+ cluster_type != QCOW2_CLUSTER_ZERO_ALLOC) {
continue;
}
- offset = qcow2_alloc_clusters(bs, s->cluster_size);
- if (offset < 0) {
- ret = offset;
- goto fail;
- }
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
+ if (!bs->backing) {
+ /* not backed; therefore we can simply deallocate the
+ * cluster */
+ l2_slice[j] = 0;
+ l2_dirty = true;
+ continue;
+ }
+
+ offset = qcow2_alloc_clusters(bs, s->cluster_size);
+ if (offset < 0) {
+ ret = offset;
+ goto fail;
+ }
- if (l2_refcount > 1) {
- /* For shared L2 tables, set the refcount accordingly (it is
- * already 1 and needs to be l2_refcount) */
- ret = qcow2_update_cluster_refcount(bs,
- offset >> s->cluster_bits,
+ if (l2_refcount > 1) {
+ /* For shared L2 tables, set the refcount accordingly
+ * (it is already 1 and needs to be l2_refcount) */
+ ret = qcow2_update_cluster_refcount(
+ bs, offset >> s->cluster_bits,
refcount_diff(1, l2_refcount), false,
QCOW2_DISCARD_OTHER);
- if (ret < 0) {
- qcow2_free_clusters(bs, offset, s->cluster_size,
- QCOW2_DISCARD_OTHER);
- goto fail;
+ if (ret < 0) {
+ qcow2_free_clusters(bs, offset, s->cluster_size,
+ QCOW2_DISCARD_OTHER);
+ goto fail;
+ }
}
}
- }
- if (offset_into_cluster(s, offset)) {
- qcow2_signal_corruption(bs, true, -1, -1,
- "Cluster allocation offset "
- "%#" PRIx64 " unaligned (L2 offset: %#"
- PRIx64 ", L2 index: %#x)", offset,
- l2_offset, j);
- if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
- qcow2_free_clusters(bs, offset, s->cluster_size,
- QCOW2_DISCARD_ALWAYS);
+ if (offset_into_cluster(s, offset)) {
+ int l2_index = slice * s->l2_slice_size + j;
+ qcow2_signal_corruption(
+ bs, true, -1, -1,
+ "Cluster allocation offset "
+ "%#" PRIx64 " unaligned (L2 offset: %#"
+ PRIx64 ", L2 index: %#x)", offset,
+ l2_offset, l2_index);
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
+ qcow2_free_clusters(bs, offset, s->cluster_size,
+ QCOW2_DISCARD_ALWAYS);
+ }
+ ret = -EIO;
+ goto fail;
}
- ret = -EIO;
- goto fail;
- }
- ret = qcow2_pre_write_overlap_check(bs, 0, offset, s->cluster_size);
- if (ret < 0) {
- if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
- qcow2_free_clusters(bs, offset, s->cluster_size,
- QCOW2_DISCARD_ALWAYS);
+ ret = qcow2_pre_write_overlap_check(bs, 0, offset,
+ s->cluster_size);
+ if (ret < 0) {
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
+ qcow2_free_clusters(bs, offset, s->cluster_size,
+ QCOW2_DISCARD_ALWAYS);
+ }
+ goto fail;
}
- goto fail;
- }
- ret = bdrv_pwrite_zeroes(bs->file, offset, s->cluster_size, 0);
- if (ret < 0) {
- if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
- qcow2_free_clusters(bs, offset, s->cluster_size,
- QCOW2_DISCARD_ALWAYS);
+ ret = bdrv_pwrite_zeroes(bs->file, offset, s->cluster_size, 0);
+ if (ret < 0) {
+ if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) {
+ qcow2_free_clusters(bs, offset, s->cluster_size,
+ QCOW2_DISCARD_ALWAYS);
+ }
+ goto fail;
}
- goto fail;
- }
- if (l2_refcount == 1) {
- l2_table[j] = cpu_to_be64(offset | QCOW_OFLAG_COPIED);
- } else {
- l2_table[j] = cpu_to_be64(offset);
+ if (l2_refcount == 1) {
+ l2_slice[j] = cpu_to_be64(offset | QCOW_OFLAG_COPIED);
+ } else {
+ l2_slice[j] = cpu_to_be64(offset);
+ }
+ l2_dirty = true;
}
- l2_dirty = true;
- }
- if (is_active_l1) {
- if (l2_dirty) {
- qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
- qcow2_cache_depends_on_flush(s->l2_table_cache);
- }
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
- } else {
- if (l2_dirty) {
- ret = qcow2_pre_write_overlap_check(bs,
- QCOW2_OL_INACTIVE_L2 | QCOW2_OL_ACTIVE_L2, l2_offset,
- s->cluster_size);
- if (ret < 0) {
- goto fail;
+ if (is_active_l1) {
+ if (l2_dirty) {
+ qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_slice);
+ qcow2_cache_depends_on_flush(s->l2_table_cache);
}
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
+ } else {
+ if (l2_dirty) {
+ ret = qcow2_pre_write_overlap_check(
+ bs, QCOW2_OL_INACTIVE_L2 | QCOW2_OL_ACTIVE_L2,
+ slice_offset, slice_size2);
+ if (ret < 0) {
+ goto fail;
+ }
- ret = bdrv_write(bs->file, l2_offset / BDRV_SECTOR_SIZE,
- (void *)l2_table, s->cluster_sectors);
- if (ret < 0) {
- goto fail;
+ ret = bdrv_pwrite(bs->file, slice_offset,
+ l2_slice, slice_size2);
+ if (ret < 0) {
+ goto fail;
+ }
}
}
}
ret = 0;
fail:
- if (l2_table) {
+ if (l2_slice) {
if (!is_active_l1) {
- qemu_vfree(l2_table);
+ qemu_vfree(l2_slice);
} else {
- qcow2_cache_put(s->l2_table_cache, (void **) &l2_table);
+ qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice);
}
}
return ret;
}
for (i = 0; i < s->nb_snapshots; i++) {
- int l1_sectors = DIV_ROUND_UP(s->snapshots[i].l1_size *
- sizeof(uint64_t), BDRV_SECTOR_SIZE);
+ int l1_size2;
+ uint64_t *new_l1_table;
+ Error *local_err = NULL;
+
+ ret = qcow2_validate_table(bs, s->snapshots[i].l1_table_offset,
+ s->snapshots[i].l1_size, sizeof(uint64_t),
+ QCOW_MAX_L1_SIZE, "Snapshot L1 table",
+ &local_err);
+ if (ret < 0) {
+ error_report_err(local_err);
+ goto fail;
+ }
- uint64_t *new_l1_table =
- g_try_realloc(l1_table, l1_sectors * BDRV_SECTOR_SIZE);
+ l1_size2 = s->snapshots[i].l1_size * sizeof(uint64_t);
+ new_l1_table = g_try_realloc(l1_table, l1_size2);
if (!new_l1_table) {
ret = -ENOMEM;
l1_table = new_l1_table;
- ret = bdrv_read(bs->file,
- s->snapshots[i].l1_table_offset / BDRV_SECTOR_SIZE,
- (void *)l1_table, l1_sectors);
+ ret = bdrv_pread(bs->file, s->snapshots[i].l1_table_offset,
+ l1_table, l1_size2);
if (ret < 0) {
goto fail;
}