diff options
| -rw-r--r-- | block/qcow2.c | 111 | ||||
| -rw-r--r-- | block/qcow2.h | 3 |
2 files changed, 103 insertions, 11 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 0f1be2e384..f9e045ff2b 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -442,6 +442,22 @@ static QemuOptsList qcow2_runtime_opts = { .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 */ } }, }; @@ -457,6 +473,61 @@ static const char *overlap_bool_option_names[QCOW2_OL_MAX_BITNR] = { [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) { @@ -707,17 +778,43 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, } } - /* alloc L2 table/refcount block cache */ - l2_cache_size = DEFAULT_L2_CACHE_BYTE_SIZE / s->cluster_size; + /* 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 = l2_cache_size / DEFAULT_L2_REFCOUNT_SIZE_RATIO; + 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); if (s->l2_table_cache == NULL || s->refcount_block_cache == NULL) { @@ -809,14 +906,6 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, } /* 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)); diff --git a/block/qcow2.h b/block/qcow2.h index 671783defe..6aeb7ea90f 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -91,6 +91,9 @@ #define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table" #define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1" #define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2" +#define QCOW2_OPT_CACHE_SIZE "cache-size" +#define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size" +#define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size" typedef struct QCowHeader { uint32_t magic; 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