diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2013-06-19 13:44:19 +0200 |
|---|---|---|
| committer | Stefan Hajnoczi <stefanha@redhat.com> | 2013-06-24 10:25:17 +0200 |
| commit | 67af674e478054086f972811dd0a11289afa39a9 (patch) | |
| tree | 9d1fbd115bc79b44f4ae73345158d623976e06ee /block/qcow2.c | |
| parent | 6cfcb9b8b91d303ab51b78623f2299b5288d2d51 (diff) | |
qcow2: Options to enable discard for freed clusters
Deleted snapshots are discarded in the image file by default, discard
requests take their default from the -drive discard=... option and other
places that free clusters must always be enabled explicitly.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'block/qcow2.c')
| -rw-r--r-- | block/qcow2.c | 26 |
1 files changed, 26 insertions, 0 deletions
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) { |