return 0;
}
+/**
+ * Set open flags for a given discard mode
+ *
+ * Return 0 on success, -1 if the discard mode was invalid.
+ */
+int bdrv_parse_discard_flags(const char *mode, int *flags)
+{
+ *flags &= ~BDRV_O_UNMAP;
+
+ if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) {
+ /* do nothing */
+ } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) {
+ *flags |= BDRV_O_UNMAP;
+ } else {
+ return -1;
+ }
+
+ return 0;
+}
+
/**
* Set open flags for a given cache mode
*
/*
* Common part for opening disk images and files
+ *
+ * Removes all processed options from *options.
*/
static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
- const char *filename,
+ const char *filename, QDict *options,
int flags, BlockDriver *drv)
{
int ret, open_flags;
assert(drv != NULL);
assert(bs->file == NULL);
+ assert(options != NULL && bs->options != options);
trace_bdrv_open_common(bs, filename, flags, drv->format_name);
+ if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) {
+ return -ENOTSUP;
+ }
+
+ /* bdrv_open() with directly using a protocol as drv. This layer is already
+ * opened, so assign it to bs (while file becomes a closed BlockDriverState)
+ * and return immediately. */
+ if (file != NULL && drv->bdrv_file_open) {
+ bdrv_swap(file, bs);
+ return 0;
+ }
+
bs->open_flags = flags;
bs->buffer_alignment = 512;
bdrv_enable_copy_on_read(bs);
}
- pstrcpy(bs->filename, sizeof(bs->filename), filename);
-
- if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) {
- return -ENOTSUP;
+ if (filename != NULL) {
+ pstrcpy(bs->filename, sizeof(bs->filename), filename);
+ } else {
+ bs->filename[0] = '\0';
}
bs->drv = drv;
/* Open the image, either directly or using a protocol */
if (drv->bdrv_file_open) {
- if (file != NULL) {
- bdrv_swap(file, bs);
- ret = 0;
- } else {
- ret = drv->bdrv_file_open(bs, filename, open_flags);
- }
+ assert(file == NULL);
+ assert(drv->bdrv_parse_filename || filename != NULL);
+ ret = drv->bdrv_file_open(bs, filename, options, open_flags);
} else {
assert(file != NULL);
bs->file = file;
- ret = drv->bdrv_open(bs, open_flags);
+ ret = drv->bdrv_open(bs, options, open_flags);
}
if (ret < 0) {
#ifndef _WIN32
if (bs->is_temporary) {
+ assert(filename != NULL);
unlink(filename);
}
#endif
/*
* Opens a file using a protocol (file, host_device, nbd, ...)
+ *
+ * options is a QDict of options to pass to the block drivers, or NULL for an
+ * empty set of options. The reference to the QDict belongs to the block layer
+ * after the call (even on failure), so if the caller intends to reuse the
+ * dictionary, it needs to use QINCREF() before calling bdrv_file_open.
*/
-int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
+int bdrv_file_open(BlockDriverState **pbs, const char *filename,
+ QDict *options, int flags)
{
BlockDriverState *bs;
BlockDriver *drv;
+ const char *drvname;
int ret;
- drv = bdrv_find_protocol(filename);
- if (!drv) {
- return -ENOENT;
+ /* NULL means an empty set of options */
+ if (options == NULL) {
+ options = qdict_new();
}
bs = bdrv_new("");
- ret = bdrv_open_common(bs, NULL, filename, flags, drv);
+ bs->options = options;
+ options = qdict_clone_shallow(options);
+
+ /* Find the right block driver */
+ drvname = qdict_get_try_str(options, "driver");
+ if (drvname) {
+ drv = bdrv_find_whitelisted_format(drvname);
+ qdict_del(options, "driver");
+ } else if (filename) {
+ drv = bdrv_find_protocol(filename);
+ } else {
+ qerror_report(ERROR_CLASS_GENERIC_ERROR,
+ "Must specify either driver or file");
+ drv = NULL;
+ }
+
+ if (!drv) {
+ ret = -ENOENT;
+ goto fail;
+ }
+
+ /* Parse the filename and open it */
+ if (drv->bdrv_parse_filename && filename) {
+ Error *local_err = NULL;
+ drv->bdrv_parse_filename(filename, options, &local_err);
+ if (error_is_set(&local_err)) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ ret = -EINVAL;
+ goto fail;
+ }
+ } else if (!drv->bdrv_parse_filename && !filename) {
+ qerror_report(ERROR_CLASS_GENERIC_ERROR,
+ "The '%s' block driver requires a file name",
+ drv->format_name);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ ret = bdrv_open_common(bs, NULL, filename, options, flags, drv);
if (ret < 0) {
- bdrv_delete(bs);
- return ret;
+ goto fail;
+ }
+
+ /* Check if any unknown options were used */
+ if (qdict_size(options) != 0) {
+ const QDictEntry *entry = qdict_first(options);
+ qerror_report(ERROR_CLASS_GENERIC_ERROR, "Block protocol '%s' doesn't "
+ "support the option '%s'",
+ drv->format_name, entry->key);
+ ret = -EINVAL;
+ goto fail;
}
+ QDECREF(options);
+
bs->growable = 1;
*pbs = bs;
return 0;
+
+fail:
+ QDECREF(options);
+ if (!bs->drv) {
+ QDECREF(bs->options);
+ }
+ bdrv_delete(bs);
+ return ret;
}
int bdrv_open_backing_file(BlockDriverState *bs)
/* backing files always opened read-only */
back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT);
- ret = bdrv_open(bs->backing_hd, backing_filename, back_flags, back_drv);
+ ret = bdrv_open(bs->backing_hd, backing_filename, NULL,
+ back_flags, back_drv);
if (ret < 0) {
bdrv_delete(bs->backing_hd);
bs->backing_hd = NULL;
return 0;
}
+static void extract_subqdict(QDict *src, QDict **dst, const char *start)
+{
+ const QDictEntry *entry, *next;
+ const char *p;
+
+ *dst = qdict_new();
+ entry = qdict_first(src);
+
+ while (entry != NULL) {
+ next = qdict_next(src, entry);
+ if (strstart(entry->key, start, &p)) {
+ qobject_incref(entry->value);
+ qdict_put_obj(*dst, p, entry->value);
+ qdict_del(src, entry->key);
+ }
+ entry = next;
+ }
+}
+
/*
* Opens a disk image (raw, qcow2, vmdk, ...)
+ *
+ * options is a QDict of options to pass to the block drivers, or NULL for an
+ * empty set of options. The reference to the QDict belongs to the block layer
+ * after the call (even on failure), so if the caller intends to reuse the
+ * dictionary, it needs to use QINCREF() before calling bdrv_open.
*/
-int bdrv_open(BlockDriverState *bs, const char *filename, int flags,
- BlockDriver *drv)
+int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
+ int flags, BlockDriver *drv)
{
int ret;
/* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */
char tmp_filename[PATH_MAX + 1];
BlockDriverState *file = NULL;
+ QDict *file_options = NULL;
+
+ /* NULL means an empty set of options */
+ if (options == NULL) {
+ options = qdict_new();
+ }
+ bs->options = options;
+ options = qdict_clone_shallow(options);
+
+ /* For snapshot=on, create a temporary qcow2 overlay */
if (flags & BDRV_O_SNAPSHOT) {
BlockDriverState *bs1;
int64_t total_size;
- int is_protocol = 0;
BlockDriver *bdrv_qcow2;
- QEMUOptionParameter *options;
+ QEMUOptionParameter *create_options;
char backing_filename[PATH_MAX];
+ if (qdict_size(options) != 0) {
+ error_report("Can't use snapshot=on with driver-specific options");
+ ret = -EINVAL;
+ goto fail;
+ }
+ assert(filename != NULL);
+
/* if snapshot, we create a temporary backing file and open it
instead of opening 'filename' directly */
/* if there is a backing file, use it */
bs1 = bdrv_new("");
- ret = bdrv_open(bs1, filename, 0, drv);
+ ret = bdrv_open(bs1, filename, NULL, 0, drv);
if (ret < 0) {
bdrv_delete(bs1);
- return ret;
+ goto fail;
}
total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK;
- if (bs1->drv && bs1->drv->protocol_name)
- is_protocol = 1;
-
bdrv_delete(bs1);
ret = get_tmp_filename(tmp_filename, sizeof(tmp_filename));
if (ret < 0) {
- return ret;
+ goto fail;
}
/* Real path is meaningless for protocols */
- if (is_protocol)
+ if (path_has_protocol(filename)) {
snprintf(backing_filename, sizeof(backing_filename),
"%s", filename);
- else if (!realpath(filename, backing_filename))
- return -errno;
+ } else if (!realpath(filename, backing_filename)) {
+ ret = -errno;
+ goto fail;
+ }
bdrv_qcow2 = bdrv_find_format("qcow2");
- options = parse_option_parameters("", bdrv_qcow2->create_options, NULL);
+ create_options = parse_option_parameters("", bdrv_qcow2->create_options,
+ NULL);
- set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size);
- set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename);
+ set_option_parameter_int(create_options, BLOCK_OPT_SIZE, total_size);
+ set_option_parameter(create_options, BLOCK_OPT_BACKING_FILE,
+ backing_filename);
if (drv) {
- set_option_parameter(options, BLOCK_OPT_BACKING_FMT,
+ set_option_parameter(create_options, BLOCK_OPT_BACKING_FMT,
drv->format_name);
}
- ret = bdrv_create(bdrv_qcow2, tmp_filename, options);
- free_option_parameters(options);
+ ret = bdrv_create(bdrv_qcow2, tmp_filename, create_options);
+ free_option_parameters(create_options);
if (ret < 0) {
- return ret;
+ goto fail;
}
filename = tmp_filename;
flags |= BDRV_O_ALLOW_RDWR;
}
- ret = bdrv_file_open(&file, filename, bdrv_open_flags(bs, flags));
+ extract_subqdict(options, &file_options, "file.");
+
+ ret = bdrv_file_open(&file, filename, file_options,
+ bdrv_open_flags(bs, flags));
if (ret < 0) {
- return ret;
+ goto fail;
}
/* Find the right image format driver */
}
/* Open the image */
- ret = bdrv_open_common(bs, file, filename, flags, drv);
+ ret = bdrv_open_common(bs, file, filename, options, flags, drv);
if (ret < 0) {
goto unlink_and_fail;
}
if ((flags & BDRV_O_NO_BACKING) == 0) {
ret = bdrv_open_backing_file(bs);
if (ret < 0) {
- bdrv_close(bs);
- return ret;
+ goto close_and_fail;
}
}
+ /* Check if any unknown options were used */
+ if (qdict_size(options) != 0) {
+ const QDictEntry *entry = qdict_first(options);
+ qerror_report(ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by "
+ "device '%s' doesn't support the option '%s'",
+ drv->format_name, bs->device_name, entry->key);
+
+ ret = -EINVAL;
+ goto close_and_fail;
+ }
+ QDECREF(options);
+
if (!bdrv_key_required(bs)) {
bdrv_dev_change_media_cb(bs, true);
}
if (bs->is_temporary) {
unlink(filename);
}
+fail:
+ QDECREF(bs->options);
+ QDECREF(options);
+ bs->options = NULL;
+ return ret;
+
+close_and_fail:
+ bdrv_close(bs);
+ QDECREF(options);
return ret;
}
bs->valid_key = 0;
bs->sg = 0;
bs->growable = 0;
+ QDECREF(bs->options);
+ bs->options = NULL;
if (bs->file != NULL) {
bdrv_delete(bs->file);
BlockDriverState *bs;
QTAILQ_FOREACH(bs, &bdrv_states, list) {
- int ret = bdrv_commit(bs);
- if (ret < 0) {
- return ret;
+ if (bs->drv && bs->backing_hd) {
+ int ret = bdrv_commit(bs);
+ if (ret < 0) {
+ return ret;
+ }
}
}
return 0;
return -EACCES;
if (bdrv_in_use(bs))
return -EBUSY;
-
- /* There better not be any in-flight IOs when we truncate the device. */
- bdrv_drain_all();
-
ret = drv->bdrv_truncate(bs, offset);
if (ret == 0) {
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
if (bs->file) {
drv->bdrv_close(bs);
ret = bdrv_snapshot_goto(bs->file, snapshot_id);
- open_ret = drv->bdrv_open(bs, bs->open_flags);
+ open_ret = drv->bdrv_open(bs, NULL, bs->open_flags);
if (open_ret < 0) {
bdrv_delete(bs->file);
bs->drv = NULL;
bdrv_reset_dirty(bs, sector_num, nb_sectors);
}
+ /* Do nothing if disabled. */
+ if (!(bs->open_flags & BDRV_O_UNMAP)) {
+ return 0;
+ }
+
if (bs->drv->bdrv_co_discard) {
return bs->drv->bdrv_co_discard(bs, sector_num, nb_sectors);
} else if (bs->drv->bdrv_aio_discard) {
bs = bdrv_new("");
- ret = bdrv_open(bs, backing_file->value.s, back_flags, backing_drv);
+ ret = bdrv_open(bs, backing_file->value.s, NULL, back_flags,
+ backing_drv);
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not open '%s'",
backing_file->value.s);
bdrv_delete(bs);
}
}
+
+AioContext *bdrv_get_aio_context(BlockDriverState *bs)
+{
+ /* Currently BlockDriverState always uses the main loop AioContext */
+ return qemu_get_aio_context();
+}