diff options
Diffstat (limited to 'block/qcow2.c')
| -rw-r--r-- | block/qcow2.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index eee7eaf7b3..c1abaffa19 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -425,6 +425,8 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, Error *local_err = NULL; uint64_t ext_end; uint64_t l1_vm_state_index; + const char *opt_overlap_check; + int overlap_check_template = 0; ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); if (ret < 0) { @@ -688,7 +690,32 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, s->discard_passthrough[QCOW2_DISCARD_OTHER] = qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false); - s->overlap_check = QCOW2_OL_CACHED; + opt_overlap_check = qemu_opt_get(opts, "overlap-check") ?: "cached"; + if (!strcmp(opt_overlap_check, "none")) { + overlap_check_template = 0; + } else if (!strcmp(opt_overlap_check, "constant")) { + overlap_check_template = QCOW2_OL_CONSTANT; + } else if (!strcmp(opt_overlap_check, "cached")) { + overlap_check_template = QCOW2_OL_CACHED; + } else if (!strcmp(opt_overlap_check, "all")) { + overlap_check_template = QCOW2_OL_ALL; + } else { + 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; + } + + s->overlap_check = 0; + for (i = 0; i < QCOW2_OL_MAX_BITNR; i++) { + /* overlap-check defines a template bitmask, but every flag may be + * overwritten through the associated boolean option */ + s->overlap_check |= + qemu_opt_get_bool(opts, overlap_bool_option_names[i], + overlap_check_template & (1 << i)) << i; + } qemu_opts_del(opts); |