#include "qemu/error-report.h"
#include "qapi/qmp/qerror.h"
#include "qapi/qmp/qbool.h"
+#include "qapi/util.h"
+#include "qapi/qmp/types.h"
+#include "qapi-event.h"
#include "trace.h"
#include "qemu/option_int.h"
#ifdef DEBUG_EXT
printf("ext.magic = 0x%x\n", ext.magic);
#endif
- if (ext.len > end_offset - offset) {
+ if (offset > end_offset || ext.len > end_offset - offset) {
error_setg(errp, "Header extension too large");
return -EINVAL;
}
vsnprintf(msg, sizeof(msg), fmt, ap);
va_end(ap);
- error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, bs->device_name, "qcow2",
- msg);
+ error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
+ bdrv_get_device_name(bs), "qcow2", msg);
}
static void report_unsupported_feature(BlockDriverState *bs,
.help = "Selects which overlap checks to perform from a range of "
"templates (none, constant, cached, all)",
},
+ {
+ .name = QCOW2_OPT_OVERLAP_TEMPLATE,
+ .type = QEMU_OPT_STRING,
+ .help = "Selects which overlap checks to perform from a range of "
+ "templates (none, constant, cached, all)",
+ },
{
.name = QCOW2_OPT_OVERLAP_MAIN_HEADER,
.type = QEMU_OPT_BOOL,
.type = QEMU_OPT_BOOL,
.help = "Check for unintended writes into an inactive L2 table",
},
+ {
+ .name = QCOW2_OPT_CACHE_SIZE,
+ .type = QEMU_OPT_SIZE,
+ .help = "Maximum combined metadata (L2 tables and refcount blocks) "
+ "cache size",
+ },
+ {
+ .name = QCOW2_OPT_L2_CACHE_SIZE,
+ .type = QEMU_OPT_SIZE,
+ .help = "Maximum L2 table cache size",
+ },
+ {
+ .name = QCOW2_OPT_REFCOUNT_CACHE_SIZE,
+ .type = QEMU_OPT_SIZE,
+ .help = "Maximum refcount block cache size",
+ },
{ /* end of list */ }
},
};
[QCOW2_OL_INACTIVE_L2_BITNR] = QCOW2_OPT_OVERLAP_INACTIVE_L2,
};
+static void read_cache_sizes(QemuOpts *opts, uint64_t *l2_cache_size,
+ uint64_t *refcount_cache_size, Error **errp)
+{
+ uint64_t combined_cache_size;
+ bool l2_cache_size_set, refcount_cache_size_set, combined_cache_size_set;
+
+ combined_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_CACHE_SIZE);
+ l2_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_L2_CACHE_SIZE);
+ refcount_cache_size_set = qemu_opt_get(opts, QCOW2_OPT_REFCOUNT_CACHE_SIZE);
+
+ combined_cache_size = qemu_opt_get_size(opts, QCOW2_OPT_CACHE_SIZE, 0);
+ *l2_cache_size = qemu_opt_get_size(opts, QCOW2_OPT_L2_CACHE_SIZE, 0);
+ *refcount_cache_size = qemu_opt_get_size(opts,
+ QCOW2_OPT_REFCOUNT_CACHE_SIZE, 0);
+
+ if (combined_cache_size_set) {
+ if (l2_cache_size_set && refcount_cache_size_set) {
+ error_setg(errp, QCOW2_OPT_CACHE_SIZE ", " QCOW2_OPT_L2_CACHE_SIZE
+ " and " QCOW2_OPT_REFCOUNT_CACHE_SIZE " may not be set "
+ "the same time");
+ return;
+ } else if (*l2_cache_size > combined_cache_size) {
+ error_setg(errp, QCOW2_OPT_L2_CACHE_SIZE " may not exceed "
+ QCOW2_OPT_CACHE_SIZE);
+ return;
+ } else if (*refcount_cache_size > combined_cache_size) {
+ error_setg(errp, QCOW2_OPT_REFCOUNT_CACHE_SIZE " may not exceed "
+ QCOW2_OPT_CACHE_SIZE);
+ return;
+ }
+
+ if (l2_cache_size_set) {
+ *refcount_cache_size = combined_cache_size - *l2_cache_size;
+ } else if (refcount_cache_size_set) {
+ *l2_cache_size = combined_cache_size - *refcount_cache_size;
+ } else {
+ *refcount_cache_size = combined_cache_size
+ / (DEFAULT_L2_REFCOUNT_SIZE_RATIO + 1);
+ *l2_cache_size = combined_cache_size - *refcount_cache_size;
+ }
+ } else {
+ if (!l2_cache_size_set && !refcount_cache_size_set) {
+ *l2_cache_size = DEFAULT_L2_CACHE_BYTE_SIZE;
+ *refcount_cache_size = *l2_cache_size
+ / DEFAULT_L2_REFCOUNT_SIZE_RATIO;
+ } else if (!l2_cache_size_set) {
+ *l2_cache_size = *refcount_cache_size
+ * DEFAULT_L2_REFCOUNT_SIZE_RATIO;
+ } else if (!refcount_cache_size_set) {
+ *refcount_cache_size = *l2_cache_size
+ / DEFAULT_L2_REFCOUNT_SIZE_RATIO;
+ }
+ }
+}
+
static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
unsigned int len, i;
int ret = 0;
QCowHeader header;
- QemuOpts *opts;
+ QemuOpts *opts = NULL;
Error *local_err = NULL;
uint64_t ext_end;
uint64_t l1_vm_state_index;
- const char *opt_overlap_check;
+ const char *opt_overlap_check, *opt_overlap_check_template;
int overlap_check_template = 0;
+ uint64_t l2_cache_size, refcount_cache_size;
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
if (ret < 0) {
s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */
s->l2_size = 1 << s->l2_bits;
+ /* 2^(s->refcount_order - 3) is the refcount width in bytes */
+ s->refcount_block_bits = s->cluster_bits - (s->refcount_order - 3);
+ s->refcount_block_size = 1 << s->refcount_block_bits;
bs->total_sectors = header.size / 512;
s->csize_shift = (62 - (s->cluster_bits - 8));
s->csize_mask = (1 << (s->cluster_bits - 8)) - 1;
if (s->l1_size > 0) {
- s->l1_table = g_malloc0(
+ s->l1_table = qemu_try_blockalign(bs->file,
align_offset(s->l1_size * sizeof(uint64_t), 512));
+ if (s->l1_table == NULL) {
+ error_setg(errp, "Could not allocate L1 table");
+ ret = -ENOMEM;
+ goto fail;
+ }
ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table,
s->l1_size * sizeof(uint64_t));
if (ret < 0) {
}
}
+ /* get L2 table/refcount block cache size from command line options */
+ opts = qemu_opts_create(&qcow2_runtime_opts, NULL, 0, &error_abort);
+ qemu_opts_absorb_qdict(opts, options, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ read_cache_sizes(opts, &l2_cache_size, &refcount_cache_size, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ l2_cache_size /= s->cluster_size;
+ if (l2_cache_size < MIN_L2_CACHE_SIZE) {
+ l2_cache_size = MIN_L2_CACHE_SIZE;
+ }
+ if (l2_cache_size > INT_MAX) {
+ error_setg(errp, "L2 cache size too big");
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ refcount_cache_size /= s->cluster_size;
+ if (refcount_cache_size < MIN_REFCOUNT_CACHE_SIZE) {
+ refcount_cache_size = MIN_REFCOUNT_CACHE_SIZE;
+ }
+ if (refcount_cache_size > INT_MAX) {
+ error_setg(errp, "Refcount cache size too big");
+ ret = -EINVAL;
+ goto fail;
+ }
+
/* alloc L2 table/refcount block cache */
- s->l2_table_cache = qcow2_cache_create(bs, L2_CACHE_SIZE);
- s->refcount_block_cache = qcow2_cache_create(bs, REFCOUNT_CACHE_SIZE);
+ s->l2_table_cache = qcow2_cache_create(bs, l2_cache_size);
+ s->refcount_block_cache = qcow2_cache_create(bs, refcount_cache_size);
+ if (s->l2_table_cache == NULL || s->refcount_block_cache == NULL) {
+ error_setg(errp, "Could not allocate metadata caches");
+ ret = -ENOMEM;
+ goto fail;
+ }
s->cluster_cache = g_malloc(s->cluster_size);
/* one more sector for decompressed data alignment */
- s->cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size
- + 512);
+ s->cluster_data = qemu_try_blockalign(bs->file, QCOW_MAX_CRYPT_CLUSTERS
+ * s->cluster_size + 512);
+ if (s->cluster_data == NULL) {
+ error_setg(errp, "Could not allocate temporary cluster buffer");
+ ret = -ENOMEM;
+ goto fail;
+ }
+
s->cluster_cache_offset = -1;
s->flags = flags;
(s->incompatible_features & QCOW2_INCOMPAT_DIRTY)) {
BdrvCheckResult result = {0};
- ret = qcow2_check(bs, &result, BDRV_FIX_ERRORS);
+ ret = qcow2_check(bs, &result, BDRV_FIX_ERRORS | BDRV_FIX_LEAKS);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not repair dirty image");
goto fail;
}
/* Enable lazy_refcounts according to image and command line options */
- opts = qemu_opts_create(&qcow2_runtime_opts, NULL, 0, &error_abort);
- qemu_opts_absorb_qdict(opts, options, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
- ret = -EINVAL;
- goto fail;
- }
-
s->use_lazy_refcounts = qemu_opt_get_bool(opts, QCOW2_OPT_LAZY_REFCOUNTS,
(s->compatible_features & QCOW2_COMPAT_LAZY_REFCOUNTS));
s->discard_passthrough[QCOW2_DISCARD_OTHER] =
qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false);
- opt_overlap_check = qemu_opt_get(opts, "overlap-check") ?: "cached";
+ opt_overlap_check = qemu_opt_get(opts, QCOW2_OPT_OVERLAP);
+ opt_overlap_check_template = qemu_opt_get(opts, QCOW2_OPT_OVERLAP_TEMPLATE);
+ if (opt_overlap_check_template && opt_overlap_check &&
+ strcmp(opt_overlap_check_template, opt_overlap_check))
+ {
+ error_setg(errp, "Conflicting values for qcow2 options '"
+ QCOW2_OPT_OVERLAP "' ('%s') and '" QCOW2_OPT_OVERLAP_TEMPLATE
+ "' ('%s')", opt_overlap_check, opt_overlap_check_template);
+ ret = -EINVAL;
+ goto fail;
+ }
+ if (!opt_overlap_check) {
+ opt_overlap_check = opt_overlap_check_template ?: "cached";
+ }
+
if (!strcmp(opt_overlap_check, "none")) {
overlap_check_template = 0;
} else if (!strcmp(opt_overlap_check, "constant")) {
error_setg(errp, "Unsupported value '%s' for qcow2 option "
"'overlap-check'. Allowed are either of the following: "
"none, constant, cached, all", opt_overlap_check);
- qemu_opts_del(opts);
ret = -EINVAL;
goto fail;
}
}
qemu_opts_del(opts);
+ opts = NULL;
if (s->use_lazy_refcounts && s->qcow_version < 3) {
error_setg(errp, "Lazy refcounts require a qcow2 image with at least "
return ret;
fail:
+ qemu_opts_del(opts);
g_free(s->unknown_header_fields);
cleanup_unknown_header_ext(bs);
qcow2_free_snapshots(bs);
qcow2_refcount_close(bs);
- g_free(s->l1_table);
+ qemu_vfree(s->l1_table);
/* else pre-write overlap checks in cache_destroy may crash */
s->l1_table = NULL;
if (s->l2_table_cache) {
*/
if (!cluster_data) {
cluster_data =
- qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
+ qemu_try_blockalign(bs->file, QCOW_MAX_CRYPT_CLUSTERS
+ * s->cluster_size);
+ if (cluster_data == NULL) {
+ ret = -ENOMEM;
+ goto fail;
+ }
}
assert(cur_nr_sectors <=
if (s->crypt_method) {
if (!cluster_data) {
- cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS *
- s->cluster_size);
+ cluster_data = qemu_try_blockalign(bs->file,
+ QCOW_MAX_CRYPT_CLUSTERS
+ * s->cluster_size);
+ if (cluster_data == NULL) {
+ ret = -ENOMEM;
+ goto fail;
+ }
}
assert(hd_qiov.size <=
static void qcow2_close(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
- g_free(s->l1_table);
+ qemu_vfree(s->l1_table);
/* else pre-write overlap checks in cache_destroy may crash */
s->l1_table = NULL;
int ret;
QCowL2Meta *meta;
- nb_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+ nb_sectors = bdrv_nb_sectors(bs);
offset = 0;
while (nb_sectors) {
static int qcow2_create2(const char *filename, int64_t total_size,
const char *backing_file, const char *backing_format,
- int flags, size_t cluster_size, int prealloc,
+ int flags, size_t cluster_size, PreallocMode prealloc,
QemuOpts *opts, int version,
Error **errp)
{
Error *local_err = NULL;
int ret;
+ if (prealloc == PREALLOC_MODE_FULL || prealloc == PREALLOC_MODE_FALLOC) {
+ int64_t meta_size = 0;
+ uint64_t nreftablee, nrefblocke, nl1e, nl2e;
+ int64_t aligned_total_size = align_offset(total_size, cluster_size);
+
+ /* header: 1 cluster */
+ meta_size += cluster_size;
+
+ /* total size of L2 tables */
+ nl2e = aligned_total_size / cluster_size;
+ nl2e = align_offset(nl2e, cluster_size / sizeof(uint64_t));
+ meta_size += nl2e * sizeof(uint64_t);
+
+ /* total size of L1 tables */
+ nl1e = nl2e * sizeof(uint64_t) / cluster_size;
+ nl1e = align_offset(nl1e, cluster_size / sizeof(uint64_t));
+ meta_size += nl1e * sizeof(uint64_t);
+
+ /* total size of refcount blocks
+ *
+ * note: every host cluster is reference-counted, including metadata
+ * (even refcount blocks are recursively included).
+ * Let:
+ * a = total_size (this is the guest disk size)
+ * m = meta size not including refcount blocks and refcount tables
+ * c = cluster size
+ * y1 = number of refcount blocks entries
+ * y2 = meta size including everything
+ * then,
+ * y1 = (y2 + a)/c
+ * y2 = y1 * sizeof(u16) + y1 * sizeof(u16) * sizeof(u64) / c + m
+ * we can get y1:
+ * y1 = (a + m) / (c - sizeof(u16) - sizeof(u16) * sizeof(u64) / c)
+ */
+ nrefblocke = (aligned_total_size + meta_size + cluster_size) /
+ (cluster_size - sizeof(uint16_t) -
+ 1.0 * sizeof(uint16_t) * sizeof(uint64_t) / cluster_size);
+ nrefblocke = align_offset(nrefblocke, cluster_size / sizeof(uint16_t));
+ meta_size += nrefblocke * sizeof(uint16_t);
+
+ /* total size of refcount tables */
+ nreftablee = nrefblocke * sizeof(uint16_t) / cluster_size;
+ nreftablee = align_offset(nreftablee, cluster_size / sizeof(uint64_t));
+ meta_size += nreftablee * sizeof(uint64_t);
+
+ qemu_opt_set_number(opts, BLOCK_OPT_SIZE,
+ aligned_total_size + meta_size);
+ qemu_opt_set(opts, BLOCK_OPT_PREALLOC, PreallocMode_lookup[prealloc]);
+ }
+
ret = bdrv_create_file(filename, opts, &local_err);
if (ret < 0) {
error_propagate(errp, local_err);
.l1_size = cpu_to_be32(0),
.refcount_table_offset = cpu_to_be64(cluster_size),
.refcount_table_clusters = cpu_to_be32(1),
- .refcount_order = cpu_to_be32(3 + REFCOUNT_SHIFT),
+ .refcount_order = cpu_to_be32(4),
.header_length = cpu_to_be32(sizeof(*header)),
};
}
/* Okay, now that we have a valid image, let's give it the right size */
- ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE);
+ ret = bdrv_truncate(bs, total_size);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not resize image");
goto out;
}
/* And if we're supposed to preallocate metadata, do that now */
- if (prealloc) {
+ if (prealloc != PREALLOC_MODE_OFF) {
BDRVQcowState *s = bs->opaque;
qemu_co_mutex_lock(&s->lock);
ret = preallocate(bs);
char *backing_file = NULL;
char *backing_fmt = NULL;
char *buf = NULL;
- uint64_t sectors = 0;
+ uint64_t size = 0;
int flags = 0;
size_t cluster_size = DEFAULT_CLUSTER_SIZE;
- int prealloc = 0;
+ PreallocMode prealloc;
int version = 3;
Error *local_err = NULL;
int ret;
/* Read out options */
- sectors = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0) / 512;
+ size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
+ BDRV_SECTOR_SIZE);
backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
backing_fmt = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FMT);
if (qemu_opt_get_bool_del(opts, BLOCK_OPT_ENCRYPT, false)) {
cluster_size = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE,
DEFAULT_CLUSTER_SIZE);
buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);
- if (!buf || !strcmp(buf, "off")) {
- prealloc = 0;
- } else if (!strcmp(buf, "metadata")) {
- prealloc = 1;
- } else {
- error_setg(errp, "Invalid preallocation mode: '%s'", buf);
+ prealloc = qapi_enum_parse(PreallocMode_lookup, buf,
+ PREALLOC_MODE_MAX, PREALLOC_MODE_OFF,
+ &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
ret = -EINVAL;
goto finish;
}
flags |= BLOCK_FLAG_LAZY_REFCOUNTS;
}
- if (backing_file && prealloc) {
+ if (backing_file && prealloc != PREALLOC_MODE_OFF) {
error_setg(errp, "Backing file and preallocation cannot be used at "
"the same time");
ret = -EINVAL;
goto finish;
}
- ret = qcow2_create2(filename, sectors, backing_file, backing_fmt, flags,
+ ret = qcow2_create2(filename, size, backing_file, backing_fmt, flags,
cluster_size, prealloc, opts, version, &local_err);
if (local_err) {
error_propagate(errp, local_err);
qemu_co_mutex_lock(&s->lock);
ret = qcow2_discard_clusters(bs, sector_num << BDRV_SECTOR_BITS,
- nb_sectors, QCOW2_DISCARD_REQUEST);
+ nb_sectors, QCOW2_DISCARD_REQUEST, false);
qemu_co_mutex_unlock(&s->lock);
return ret;
}
/* align end of file to a sector boundary to ease reading with
sector based I/Os */
cluster_offset = bdrv_getlength(bs->file);
- cluster_offset = (cluster_offset + 511) & ~511;
bdrv_truncate(bs->file, cluster_offset);
return 0;
}
return ret;
}
+static int make_completely_empty(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ int ret, l1_clusters;
+ int64_t offset;
+ uint64_t *new_reftable = NULL;
+ uint64_t rt_entry, l1_size2;
+ struct {
+ uint64_t l1_offset;
+ uint64_t reftable_offset;
+ uint32_t reftable_clusters;
+ } QEMU_PACKED l1_ofs_rt_ofs_cls;
+
+ ret = qcow2_cache_empty(bs, s->l2_table_cache);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ ret = qcow2_cache_empty(bs, s->refcount_block_cache);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ /* Refcounts will be broken utterly */
+ ret = qcow2_mark_dirty(bs);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE);
+
+ l1_clusters = DIV_ROUND_UP(s->l1_size, s->cluster_size / sizeof(uint64_t));
+ l1_size2 = (uint64_t)s->l1_size * sizeof(uint64_t);
+
+ /* After this call, neither the in-memory nor the on-disk refcount
+ * information accurately describe the actual references */
+
+ ret = bdrv_write_zeroes(bs->file, s->l1_table_offset / BDRV_SECTOR_SIZE,
+ l1_clusters * s->cluster_sectors, 0);
+ if (ret < 0) {
+ goto fail_broken_refcounts;
+ }
+ memset(s->l1_table, 0, l1_size2);
+
+ BLKDBG_EVENT(bs->file, BLKDBG_EMPTY_IMAGE_PREPARE);
+
+ /* Overwrite enough clusters at the beginning of the sectors to place
+ * the refcount table, a refcount block and the L1 table in; this may
+ * overwrite parts of the existing refcount and L1 table, which is not
+ * an issue because the dirty flag is set, complete data loss is in fact
+ * desired and partial data loss is consequently fine as well */
+ ret = bdrv_write_zeroes(bs->file, s->cluster_size / BDRV_SECTOR_SIZE,
+ (2 + l1_clusters) * s->cluster_size /
+ BDRV_SECTOR_SIZE, 0);
+ /* This call (even if it failed overall) may have overwritten on-disk
+ * refcount structures; in that case, the in-memory refcount information
+ * will probably differ from the on-disk information which makes the BDS
+ * unusable */
+ if (ret < 0) {
+ goto fail_broken_refcounts;
+ }
+
+ BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE);
+ BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_UPDATE);
+
+ /* "Create" an empty reftable (one cluster) directly after the image
+ * header and an empty L1 table three clusters after the image header;
+ * the cluster between those two will be used as the first refblock */
+ cpu_to_be64w(&l1_ofs_rt_ofs_cls.l1_offset, 3 * s->cluster_size);
+ cpu_to_be64w(&l1_ofs_rt_ofs_cls.reftable_offset, s->cluster_size);
+ cpu_to_be32w(&l1_ofs_rt_ofs_cls.reftable_clusters, 1);
+ ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, l1_table_offset),
+ &l1_ofs_rt_ofs_cls, sizeof(l1_ofs_rt_ofs_cls));
+ if (ret < 0) {
+ goto fail_broken_refcounts;
+ }
+
+ s->l1_table_offset = 3 * s->cluster_size;
+
+ new_reftable = g_try_new0(uint64_t, s->cluster_size / sizeof(uint64_t));
+ if (!new_reftable) {
+ ret = -ENOMEM;
+ goto fail_broken_refcounts;
+ }
+
+ s->refcount_table_offset = s->cluster_size;
+ s->refcount_table_size = s->cluster_size / sizeof(uint64_t);
+
+ g_free(s->refcount_table);
+ s->refcount_table = new_reftable;
+ new_reftable = NULL;
+
+ /* Now the in-memory refcount information again corresponds to the on-disk
+ * information (reftable is empty and no refblocks (the refblock cache is
+ * empty)); however, this means some clusters (e.g. the image header) are
+ * referenced, but not refcounted, but the normal qcow2 code assumes that
+ * the in-memory information is always correct */
+
+ BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC);
+
+ /* Enter the first refblock into the reftable */
+ rt_entry = cpu_to_be64(2 * s->cluster_size);
+ ret = bdrv_pwrite_sync(bs->file, s->cluster_size,
+ &rt_entry, sizeof(rt_entry));
+ if (ret < 0) {
+ goto fail_broken_refcounts;
+ }
+ s->refcount_table[0] = 2 * s->cluster_size;
+
+ s->free_cluster_index = 0;
+ assert(3 + l1_clusters <= s->refcount_block_size);
+ offset = qcow2_alloc_clusters(bs, 3 * s->cluster_size + l1_size2);
+ if (offset < 0) {
+ ret = offset;
+ goto fail_broken_refcounts;
+ } else if (offset > 0) {
+ error_report("First cluster in emptied image is in use");
+ abort();
+ }
+
+ /* Now finally the in-memory information corresponds to the on-disk
+ * structures and is correct */
+ ret = qcow2_mark_clean(bs);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ ret = bdrv_truncate(bs->file, (3 + l1_clusters) * s->cluster_size);
+ if (ret < 0) {
+ goto fail;
+ }
+
+ return 0;
+
+fail_broken_refcounts:
+ /* The BDS is unusable at this point. If we wanted to make it usable, we
+ * would have to call qcow2_refcount_close(), qcow2_refcount_init(),
+ * qcow2_check_refcounts(), qcow2_refcount_close() and qcow2_refcount_init()
+ * again. However, because the functions which could have caused this error
+ * path to be taken are used by those functions as well, it's very likely
+ * that that sequence will fail as well. Therefore, just eject the BDS. */
+ bs->drv = NULL;
+
+fail:
+ g_free(new_reftable);
+ return ret;
+}
+
+static int qcow2_make_empty(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint64_t start_sector;
+ int sector_step = INT_MAX / BDRV_SECTOR_SIZE;
+ int l1_clusters, ret = 0;
+
+ l1_clusters = DIV_ROUND_UP(s->l1_size, s->cluster_size / sizeof(uint64_t));
+
+ if (s->qcow_version >= 3 && !s->snapshots &&
+ 3 + l1_clusters <= s->refcount_block_size) {
+ /* The following function only works for qcow2 v3 images (it requires
+ * the dirty flag) and only as long as there are no snapshots (because
+ * it completely empties the image). Furthermore, the L1 table and three
+ * additional clusters (image header, refcount table, one refcount
+ * block) have to fit inside one refcount block. */
+ return make_completely_empty(bs);
+ }
+
+ /* This fallback code simply discards every active cluster; this is slow,
+ * but works in all cases */
+ for (start_sector = 0; start_sector < bs->total_sectors;
+ start_sector += sector_step)
+ {
+ /* As this function is generally used after committing an external
+ * snapshot, QCOW2_DISCARD_SNAPSHOT seems appropriate. Also, the
+ * default action for this kind of discard is to pass the discard,
+ * which will ideally result in an actually smaller image file, as
+ * is probably desired. */
+ ret = qcow2_discard_clusters(bs, start_sector * BDRV_SECTOR_SIZE,
+ MIN(sector_step,
+ bs->total_sectors - start_sector),
+ QCOW2_DISCARD_SNAPSHOT, true);
+ if (ret < 0) {
+ break;
+ }
+ }
+
+ return ret;
+}
+
static coroutine_fn int qcow2_co_flush_to_os(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
.lazy_refcounts = s->compatible_features &
QCOW2_COMPAT_LAZY_REFCOUNTS,
.has_lazy_refcounts = true,
+ .corrupt = s->incompatible_features &
+ QCOW2_INCOMPAT_CORRUPT,
+ .has_corrupt = true,
};
}
* Downgrades an image's version. To achieve this, any incompatible features
* have to be removed.
*/
-static int qcow2_downgrade(BlockDriverState *bs, int target_version)
+static int qcow2_downgrade(BlockDriverState *bs, int target_version,
+ BlockDriverAmendStatusCB *status_cb)
{
BDRVQcowState *s = bs->opaque;
int current_version = s->qcow_version;
/* clearing autoclear features is trivial */
s->autoclear_features = 0;
- ret = qcow2_expand_zero_clusters(bs);
+ ret = qcow2_expand_zero_clusters(bs, status_cb);
if (ret < 0) {
return ret;
}
return 0;
}
-static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts)
+static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,
+ BlockDriverAmendStatusCB *status_cb)
{
BDRVQcowState *s = bs->opaque;
int old_version = s->qcow_version, new_version = old_version;
return ret;
}
} else {
- ret = qcow2_downgrade(bs, new_version);
+ ret = qcow2_downgrade(bs, new_version, status_cb);
if (ret < 0) {
return ret;
}
return 0;
}
+/*
+ * If offset or size are negative, respectively, they will not be included in
+ * the BLOCK_IMAGE_CORRUPTED event emitted.
+ * fatal will be ignored for read-only BDS; corruptions found there will always
+ * be considered non-fatal.
+ */
+void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
+ int64_t size, const char *message_format, ...)
+{
+ BDRVQcowState *s = bs->opaque;
+ char *message;
+ va_list ap;
+
+ fatal = fatal && !bs->read_only;
+
+ if (s->signaled_corruption &&
+ (!fatal || (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT)))
+ {
+ return;
+ }
+
+ va_start(ap, message_format);
+ message = g_strdup_vprintf(message_format, ap);
+ va_end(ap);
+
+ if (fatal) {
+ fprintf(stderr, "qcow2: Marking image as corrupt: %s; further "
+ "corruption events will be suppressed\n", message);
+ } else {
+ fprintf(stderr, "qcow2: Image is corrupt: %s; further non-fatal "
+ "corruption events will be suppressed\n", message);
+ }
+
+ qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs), message,
+ offset >= 0, offset, size >= 0, size,
+ fatal, &error_abort);
+ g_free(message);
+
+ if (fatal) {
+ qcow2_mark_corrupt(bs);
+ bs->drv = NULL; /* make BDS unusable */
+ }
+
+ s->signaled_corruption = true;
+}
+
static QemuOptsList qcow2_create_opts = {
.name = "qcow2-create-opts",
.head = QTAILQ_HEAD_INITIALIZER(qcow2_create_opts.head),
{
.name = BLOCK_OPT_PREALLOC,
.type = QEMU_OPT_STRING,
- .help = "Preallocation mode (allowed values: off, metadata)"
+ .help = "Preallocation mode (allowed values: off, metadata, "
+ "falloc, full)"
},
{
.name = BLOCK_OPT_LAZY_REFCOUNTS,
}
};
-static BlockDriver bdrv_qcow2 = {
+BlockDriver bdrv_qcow2 = {
.format_name = "qcow2",
.instance_size = sizeof(BDRVQcowState),
.bdrv_probe = qcow2_probe,
.bdrv_co_discard = qcow2_co_discard,
.bdrv_truncate = qcow2_truncate,
.bdrv_write_compressed = qcow2_write_compressed,
+ .bdrv_make_empty = qcow2_make_empty,
.bdrv_snapshot_create = qcow2_snapshot_create,
.bdrv_snapshot_goto = qcow2_snapshot_goto,
projects / qemu.git / blobdiff