diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 17 |
1 files changed, 16 insertions, 1 deletions
@@ -765,7 +765,7 @@ static void bdrv_inherited_options(int *child_flags, QDict *child_options, /* Our block drivers take care to send flushes and respect unmap policy, * so we can default to enable both on lower layers regardless of the * corresponding parent options. */ - flags |= BDRV_O_UNMAP; + qdict_set_default_str(child_options, BDRV_OPT_DISCARD, "unmap"); /* Clear flags that only apply to the top layer */ flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ | @@ -960,6 +960,11 @@ static QemuOptsList bdrv_runtime_opts = { .type = QEMU_OPT_STRING, .help = "try to optimize zero writes (off, on, unmap)", }, + { + .name = "discard", + .type = QEMU_OPT_STRING, + .help = "discard operation (ignore/off, unmap/on)", + }, { /* end of list */ } }, }; @@ -976,6 +981,7 @@ static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file, const char *filename; const char *driver_name = NULL; const char *node_name = NULL; + const char *discard; const char *detect_zeroes; QemuOpts *opts; BlockDriver *drv; @@ -1045,6 +1051,15 @@ static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file, } } + discard = qemu_opt_get(opts, "discard"); + if (discard != NULL) { + if (bdrv_parse_discard_flags(discard, &bs->open_flags) != 0) { + error_setg(errp, "Invalid discard option"); + ret = -EINVAL; + goto fail_opts; + } + } + detect_zeroes = qemu_opt_get(opts, "detect-zeroes"); if (detect_zeroes) { BlockdevDetectZeroesOptions value = |