diff options
| -rw-r--r-- | block/qcow2-refcount.c | 5 | ||||
| -rw-r--r-- | block/qcow2.c | 26 | ||||
| -rw-r--r-- | block/qcow2.h | 5 |
3 files changed, 36 insertions, 0 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 6d35e49d32..7488988a9a 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -488,6 +488,11 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, s->free_cluster_index = cluster_index; } refcount_block[block_index] = cpu_to_be16(refcount); + if (refcount == 0 && s->discard_passthrough[type]) { + /* Try discarding, ignore errors */ + /* FIXME Doing this cluster by cluster will be painfully slow */ + bdrv_discard(bs->file, cluster_offset, 1); + } } ret = 0; diff --git a/block/qcow2.c b/block/qcow2.c index e28ea47d3d..ef8a2cac39 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -295,6 +295,22 @@ static QemuOptsList qcow2_runtime_opts = { .type = QEMU_OPT_BOOL, .help = "Postpone refcount updates", }, + { + .name = QCOW2_OPT_DISCARD_REQUEST, + .type = QEMU_OPT_BOOL, + .help = "Pass guest discard requests to the layer below", + }, + { + .name = QCOW2_OPT_DISCARD_SNAPSHOT, + .type = QEMU_OPT_BOOL, + .help = "Generate discard requests when snapshot related space " + "is freed", + }, + { + .name = QCOW2_OPT_DISCARD_OTHER, + .type = QEMU_OPT_BOOL, + .help = "Generate discard requests when other clusters are freed", + }, { /* end of list */ } }, }; @@ -532,6 +548,16 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags) 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_NEVER] = false; + s->discard_passthrough[QCOW2_DISCARD_ALWAYS] = true; + s->discard_passthrough[QCOW2_DISCARD_REQUEST] = + qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_REQUEST, + flags & BDRV_O_UNMAP); + s->discard_passthrough[QCOW2_DISCARD_SNAPSHOT] = + qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_SNAPSHOT, true); + s->discard_passthrough[QCOW2_DISCARD_OTHER] = + qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false); + qemu_opts_del(opts); if (s->use_lazy_refcounts && s->qcow_version < 3) { diff --git a/block/qcow2.h b/block/qcow2.h index 64a647938a..6f91b9a016 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -60,6 +60,9 @@ #define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts" +#define QCOW2_OPT_DISCARD_REQUEST "pass_discard_request" +#define QCOW2_OPT_DISCARD_SNAPSHOT "pass_discard_snapshot" +#define QCOW2_OPT_DISCARD_OTHER "pass_discard_other" typedef struct QCowHeader { uint32_t magic; @@ -187,6 +190,8 @@ typedef struct BDRVQcowState { int qcow_version; bool use_lazy_refcounts; + bool discard_passthrough[QCOW2_DISCARD_MAX]; + uint64_t incompatible_features; uint64_t compatible_features; uint64_t autoclear_features; |