diff --git a/block.c b/block.c index 84c0eac671..fd05a8008a 100644 --- a/block.c +++ b/block.c @@ -778,8 +778,13 @@ static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file, } assert(bs->copy_on_read == 0); /* bdrv_new() and bdrv_close() make it so */ - if (!bs->read_only && (flags & BDRV_O_COPY_ON_READ)) { - bdrv_enable_copy_on_read(bs); + if (flags & BDRV_O_COPY_ON_READ) { + if (!bs->read_only) { + bdrv_enable_copy_on_read(bs); + } else { + error_setg(errp, "Can't use copy-on-read on read-only device"); + return -EINVAL; + } } if (filename != NULL) { diff --git a/blockdev.c b/blockdev.c index e1ad319281..1f14514bea 100644 --- a/blockdev.c +++ b/blockdev.c @@ -510,10 +510,6 @@ static DriveInfo *blockdev_init(QDict *bs_opts, bdrv_flags |= ro ? 0 : BDRV_O_RDWR; - if (ro && copy_on_read) { - error_report("warning: disabling copy_on_read on read-only drive"); - } - QINCREF(bs_opts); ret = bdrv_open(dinfo->bdrv, file, bs_opts, bdrv_flags, drv, &error); @@ -601,6 +597,18 @@ QemuOptsList qemu_legacy_drive_opts = { .type = QEMU_OPT_STRING, .help = "pci address (virtio only)", }, + + /* Options that are passed on, but have special semantics with -drive */ + { + .name = "read-only", + .type = QEMU_OPT_BOOL, + .help = "open drive file as read-only", + },{ + .name = "copy-on-read", + .type = QEMU_OPT_BOOL, + .help = "copy read data from backing file into image file", + }, + { /* end of list */ } }, }; @@ -616,6 +624,7 @@ DriveInfo *drive_init(QemuOpts *all_opts, BlockInterfaceType block_default_type) int cyls, heads, secs, translation; int max_devs, bus_id, unit_id, index; const char *devaddr; + bool read_only, copy_on_read; Error *local_err = NULL; /* Change legacy command line options into QMP ones */ @@ -698,6 +707,20 @@ DriveInfo *drive_init(QemuOpts *all_opts, BlockInterfaceType block_default_type) } } + /* copy-on-read is disabled with a warning for read-only devices */ + read_only = qemu_opt_get_bool(legacy_opts, "read-only", false); + copy_on_read = qemu_opt_get_bool(legacy_opts, "copy-on-read", false); + + if (read_only && copy_on_read) { + error_report("warning: disabling copy-on-read on read-only drive"); + copy_on_read = false; + } + + qdict_put(bs_opts, "read-only", + qstring_from_str(read_only ? "on" : "off")); + qdict_put(bs_opts, "copy-on-read", + qstring_from_str(copy_on_read ? "on" :"off")); + /* Controller type */ value = qemu_opt_get(legacy_opts, "if"); if (value) {