return 0;
}
+/* TODO Remove (deprecated since 2.11)
+ * Block drivers are not supposed to automatically change bs->read_only.
+ * Instead, they should just check whether they can provide what the user
+ * explicitly requested and error out if read-write is requested, but they can
+ * only provide read-only access. */
int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp)
{
int ret = 0;
{
BlockDriver *drv = bs->drv;
+ if (!drv) {
+ return -ENOMEDIUM;
+ }
+
/* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
if (bdrv_is_sg(bs))
return 0;
*child_flags = flags;
}
+static int bdrv_backing_update_filename(BdrvChild *c, BlockDriverState *base,
+ const char *filename, Error **errp)
+{
+ BlockDriverState *parent = c->opaque;
+ int orig_flags = bdrv_get_flags(parent);
+ int ret;
+
+ if (!(orig_flags & BDRV_O_RDWR)) {
+ ret = bdrv_reopen(parent, orig_flags | BDRV_O_RDWR, errp);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ ret = bdrv_change_backing_file(parent, filename,
+ base->drv ? base->drv->format_name : "");
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "Could not update backing file link");
+ }
+
+ if (!(orig_flags & BDRV_O_RDWR)) {
+ bdrv_reopen(parent, orig_flags, NULL);
+ }
+
+ return ret;
+}
+
const BdrvChildRole child_backing = {
.get_parent_desc = bdrv_child_get_parent_desc,
.attach = bdrv_backing_attach,
.drained_begin = bdrv_child_cb_drained_begin,
.drained_end = bdrv_child_cb_drained_end,
.inactivate = bdrv_child_cb_inactivate,
+ .update_filename = bdrv_backing_update_filename,
};
static int bdrv_open_flags(BlockDriverState *bs, int flags)
goto free_exit;
}
- if (bs->backing_format[0] != '\0' && !qdict_haskey(options, "driver")) {
+ if (!reference &&
+ bs->backing_format[0] != '\0' && !qdict_haskey(options, "driver")) {
qdict_put_str(options, "driver", bs->backing_format);
}
goto fail;
}
if (file_bs != NULL) {
- file = blk_new(BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL);
+ /* Not requesting BLK_PERM_CONSISTENT_READ because we're only
+ * looking at the header to guess the image format. This works even
+ * in cases where a guest would not see a consistent state. */
+ file = blk_new(0, BLK_PERM_ALL);
blk_insert_bs(file, file_bs, &local_err);
bdrv_unref(file_bs);
if (local_err) {
const QDictEntry *entry = qdict_first(reopen_state->options);
do {
- QString *new_obj = qobject_to_qstring(entry->value);
- const char *new = qstring_get_str(new_obj);
+ QObject *new = entry->value;
+ QObject *old = qdict_get(reopen_state->bs->options, entry->key);
+
/*
- * Caution: while qdict_get_try_str() is fine, getting
- * non-string types would require more care. When
- * bs->options come from -blockdev or blockdev_add, its
- * members are typed according to the QAPI schema, but
- * when they come from -drive, they're all QString.
+ * TODO: When using -drive to specify blockdev options, all values
+ * will be strings; however, when using -blockdev, blockdev-add or
+ * filenames using the json:{} pseudo-protocol, they will be
+ * correctly typed.
+ * In contrast, reopening options are (currently) always strings
+ * (because you can only specify them through qemu-io; all other
+ * callers do not specify any options).
+ * Therefore, when using anything other than -drive to create a BDS,
+ * this cannot detect non-string options as unchanged, because
+ * qobject_is_equal() always returns false for objects of different
+ * type. In the future, this should be remedied by correctly typing
+ * all options. For now, this is not too big of an issue because
+ * the user can simply omit options which cannot be changed anyway,
+ * so they will stay unchanged.
*/
- const char *old = qdict_get_try_str(reopen_state->bs->options,
- entry->key);
-
- if (!old || strcmp(new, old)) {
+ if (!qobject_is_equal(new, old)) {
error_setg(errp, "Cannot change the option '%s'", entry->key);
ret = -EINVAL;
goto error;
static void bdrv_close(BlockDriverState *bs)
{
BdrvAioNotifier *ban, *ban_next;
+ BdrvChild *child, *next;
assert(!bs->job);
assert(!bs->refcnt);
bdrv_drain(bs); /* in case flush left pending I/O */
if (bs->drv) {
- BdrvChild *child, *next;
-
bs->drv->bdrv_close(bs);
bs->drv = NULL;
+ }
- bdrv_set_backing_hd(bs, NULL, &error_abort);
+ bdrv_set_backing_hd(bs, NULL, &error_abort);
- if (bs->file != NULL) {
- bdrv_unref_child(bs, bs->file);
- bs->file = NULL;
- }
+ if (bs->file != NULL) {
+ bdrv_unref_child(bs, bs->file);
+ bs->file = NULL;
+ }
- QLIST_FOREACH_SAFE(child, &bs->children, next, next) {
- /* TODO Remove bdrv_unref() from drivers' close function and use
- * bdrv_unref_child() here */
- if (child->bs->inherits_from == bs) {
- child->bs->inherits_from = NULL;
- }
- bdrv_detach_child(child);
+ QLIST_FOREACH_SAFE(child, &bs->children, next, next) {
+ /* TODO Remove bdrv_unref() from drivers' close function and use
+ * bdrv_unref_child() here */
+ if (child->bs->inherits_from == bs) {
+ child->bs->inherits_from = NULL;
}
-
- g_free(bs->opaque);
- bs->opaque = NULL;
- atomic_set(&bs->copy_on_read, 0);
- bs->backing_file[0] = '\0';
- bs->backing_format[0] = '\0';
- bs->total_sectors = 0;
- bs->encrypted = false;
- bs->sg = false;
- QDECREF(bs->options);
- QDECREF(bs->explicit_options);
- bs->options = NULL;
- bs->explicit_options = NULL;
- QDECREF(bs->full_open_options);
- bs->full_open_options = NULL;
+ bdrv_detach_child(child);
}
+ g_free(bs->opaque);
+ bs->opaque = NULL;
+ atomic_set(&bs->copy_on_read, 0);
+ bs->backing_file[0] = '\0';
+ bs->backing_format[0] = '\0';
+ bs->total_sectors = 0;
+ bs->encrypted = false;
+ bs->sg = false;
+ QDECREF(bs->options);
+ QDECREF(bs->explicit_options);
+ bs->options = NULL;
+ bs->explicit_options = NULL;
+ QDECREF(bs->full_open_options);
+ bs->full_open_options = NULL;
+
bdrv_release_named_dirty_bitmaps(bs);
assert(QLIST_EMPTY(&bs->dirty_bitmaps));
BlockDriver *drv = bs->drv;
int ret;
+ if (!drv) {
+ return -ENOMEDIUM;
+ }
+
/* Backing file format doesn't make sense without a backing file */
if (backing_fmt && !backing_file) {
return -EINVAL;
* if active == top, that is considered an error
*
*/
-int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
- BlockDriverState *base, const char *backing_file_str)
+int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base,
+ const char *backing_file_str)
{
- BlockDriverState *new_top_bs = NULL;
+ BdrvChild *c, *next;
Error *local_err = NULL;
int ret = -EIO;
- if (!top->drv || !base->drv) {
- goto exit;
- }
-
- new_top_bs = bdrv_find_overlay(active, top);
-
- if (new_top_bs == NULL) {
- /* we could not find the image above 'top', this is an error */
- goto exit;
- }
+ bdrv_ref(top);
- /* special case of new_top_bs->backing->bs already pointing to base - nothing
- * to do, no intermediate images */
- if (backing_bs(new_top_bs) == base) {
- ret = 0;
+ if (!top->drv || !base->drv) {
goto exit;
}
}
/* success - we can delete the intermediate states, and link top->base */
+ /* TODO Check graph modification op blockers (BLK_PERM_GRAPH_MOD) once
+ * we've figured out how they should work. */
backing_file_str = backing_file_str ? backing_file_str : base->filename;
- ret = bdrv_change_backing_file(new_top_bs, backing_file_str,
- base->drv ? base->drv->format_name : "");
- if (ret) {
- goto exit;
- }
- bdrv_set_backing_hd(new_top_bs, base, &local_err);
- if (local_err) {
- ret = -EPERM;
- error_report_err(local_err);
- goto exit;
+ QLIST_FOREACH_SAFE(c, &top->parents, next_parent, next) {
+ /* Check whether we are allowed to switch c from top to base */
+ GSList *ignore_children = g_slist_prepend(NULL, c);
+ bdrv_check_update_perm(base, NULL, c->perm, c->shared_perm,
+ ignore_children, &local_err);
+ if (local_err) {
+ ret = -EPERM;
+ error_report_err(local_err);
+ goto exit;
+ }
+ g_slist_free(ignore_children);
+
+ /* If so, update the backing file path in the image file */
+ if (c->role->update_filename) {
+ ret = c->role->update_filename(c, base, backing_file_str,
+ &local_err);
+ if (ret < 0) {
+ bdrv_abort_perm_update(base);
+ error_report_err(local_err);
+ goto exit;
+ }
+ }
+
+ /* Do the actual switch in the in-memory graph.
+ * Completes bdrv_check_update_perm() transaction internally. */
+ bdrv_ref(base);
+ bdrv_replace_child(c, base);
+ bdrv_unref(top);
}
ret = 0;
exit:
+ bdrv_unref(top);
return ret;
}
assert(!(bs->open_flags & BDRV_O_INACTIVE));
ret = drv->bdrv_truncate(bs, offset, prealloc, errp);
- if (ret == 0) {
- ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
- bdrv_dirty_bitmap_truncate(bs);
- bdrv_parent_cb_resize(bs);
- atomic_inc(&bs->write_gen);
+ if (ret < 0) {
+ return ret;
+ }
+ ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "Could not refresh total sector count");
+ } else {
+ offset = bs->total_sectors * BDRV_SECTOR_SIZE;
}
+ bdrv_dirty_bitmap_truncate(bs, offset);
+ bdrv_parent_cb_resize(bs);
+ atomic_inc(&bs->write_gen);
return ret;
}
int bdrv_has_zero_init(BlockDriverState *bs)
{
- assert(bs->drv);
+ if (!bs->drv) {
+ return 0;
+ }
/* If BS is a copy on write image, it is initialized to
the contents of the base image, which may not be zeroes. */
}
}
+ /*
+ * Update permissions, they may differ for inactive nodes.
+ *
+ * Note that the required permissions of inactive images are always a
+ * subset of the permissions required after activating the image. This
+ * allows us to just get the permissions upfront without restricting
+ * drv->bdrv_invalidate_cache().
+ *
+ * It also means that in error cases, we don't have to try and revert to
+ * the old permissions (which is an operation that could fail, too). We can
+ * just keep the extended permissions for the next time that an activation
+ * of the image is tried.
+ */
bs->open_flags &= ~BDRV_O_INACTIVE;
+ bdrv_get_cumulative_perm(bs, &perm, &shared_perm);
+ ret = bdrv_check_perm(bs, NULL, perm, shared_perm, NULL, &local_err);
+ if (ret < 0) {
+ bs->open_flags |= BDRV_O_INACTIVE;
+ error_propagate(errp, local_err);
+ return;
+ }
+ bdrv_set_perm(bs, perm, shared_perm);
+
if (bs->drv->bdrv_invalidate_cache) {
bs->drv->bdrv_invalidate_cache(bs, &local_err);
if (local_err) {
return;
}
- /* Update permissions, they may differ for inactive nodes */
- bdrv_get_cumulative_perm(bs, &perm, &shared_perm);
- ret = bdrv_check_perm(bs, NULL, perm, shared_perm, NULL, &local_err);
- if (ret < 0) {
- bs->open_flags |= BDRV_O_INACTIVE;
- error_propagate(errp, local_err);
- return;
- }
- bdrv_set_perm(bs, perm, shared_perm);
-
QLIST_FOREACH(parent, &bs->parents, next_parent) {
if (parent->role->activate) {
parent->role->activate(parent, &local_err);
aio_context_release(aio_context);
if (local_err) {
error_propagate(errp, local_err);
+ bdrv_next_cleanup(&it);
return;
}
}
BdrvChild *child, *parent;
int ret;
+ if (!bs->drv) {
+ return -ENOMEDIUM;
+ }
+
if (!setting_flag && bs->drv->bdrv_inactivate) {
ret = bs->drv->bdrv_inactivate(bs);
if (ret < 0) {
for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
ret = bdrv_inactivate_recurse(bs, pass);
if (ret < 0) {
+ bdrv_next_cleanup(&it);
goto out;
}
}
/* The size for the image must always be specified, unless we have a backing
* file and we have not been forbidden from opening it. */
- size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, 0);
+ size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, img_size);
if (backing_file && !(flags & BDRV_O_NO_BACKING)) {
BlockDriverState *bs;
char *full_backing = g_new0(char, PATH_MAX);
int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts,
BlockDriverAmendStatusCB *status_cb, void *cb_opaque)
{
+ if (!bs->drv) {
+ return -ENOMEDIUM;
+ }
if (!bs->drv->bdrv_amend_options) {
return -ENOTSUP;
}
/* candidate is the first non filter */
if (perm) {
+ bdrv_next_cleanup(&it);
return true;
}
}
projects / mirror_qemu.git / blobdiff