const char *filename, Error **errp)
{
BlockDriverState *parent = c->opaque;
- int orig_flags = bdrv_get_flags(parent);
+ bool read_only = bdrv_is_read_only(parent);
int ret;
- if (!(orig_flags & BDRV_O_RDWR)) {
- ret = bdrv_reopen(parent, orig_flags | BDRV_O_RDWR, errp);
+ if (read_only) {
+ ret = bdrv_reopen_set_read_only(parent, false, errp);
if (ret < 0) {
return ret;
}
error_setg_errno(errp, -ret, "Could not update backing file link");
}
- if (!(orig_flags & BDRV_O_RDWR)) {
- bdrv_reopen(parent, orig_flags, NULL);
+ if (read_only) {
+ bdrv_reopen_set_read_only(parent, true, NULL);
}
return ret;
static void update_flags_from_options(int *flags, QemuOpts *opts)
{
- *flags &= ~BDRV_O_CACHE_MASK;
+ *flags &= ~(BDRV_O_CACHE_MASK | BDRV_O_RDWR | BDRV_O_AUTO_RDONLY);
- assert(qemu_opt_find(opts, BDRV_OPT_CACHE_NO_FLUSH));
if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_NO_FLUSH, false)) {
*flags |= BDRV_O_NO_FLUSH;
}
- assert(qemu_opt_find(opts, BDRV_OPT_CACHE_DIRECT));
if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_DIRECT, false)) {
*flags |= BDRV_O_NOCACHE;
}
- *flags &= ~BDRV_O_RDWR;
-
- assert(qemu_opt_find(opts, BDRV_OPT_READ_ONLY));
if (!qemu_opt_get_bool_del(opts, BDRV_OPT_READ_ONLY, false)) {
*flags |= BDRV_O_RDWR;
}
- assert(qemu_opt_find(opts, BDRV_OPT_AUTO_READ_ONLY));
if (qemu_opt_get_bool_del(opts, BDRV_OPT_AUTO_READ_ONLY, false)) {
*flags |= BDRV_O_AUTO_RDONLY;
}
}
}
+/* Return true if you can reach parent going through child->inherits_from
+ * recursively. If parent or child are NULL, return false */
+static bool bdrv_inherits_from_recursive(BlockDriverState *child,
+ BlockDriverState *parent)
+{
+ while (child && child != parent) {
+ child = child->inherits_from;
+ }
+
+ return child != NULL;
+}
+
/*
* Sets the backing file link of a BDS. A new reference is created; callers
* which don't need their own reference any more must call bdrv_unref().
void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd,
Error **errp)
{
+ bool update_inherits_from = bdrv_chain_contains(bs, backing_hd) &&
+ bdrv_inherits_from_recursive(backing_hd, bs);
+
if (backing_hd) {
bdrv_ref(backing_hd);
}
bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing,
errp);
+ /* If backing_hd was already part of bs's backing chain, and
+ * inherits_from pointed recursively to bs then let's update it to
+ * point directly to bs (else it will become NULL). */
+ if (update_inherits_from) {
+ backing_hd->inherits_from = bs;
+ }
if (!bs->backing) {
bdrv_unref(backing_hd);
}
static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue,
BlockDriverState *bs,
QDict *options,
- int flags,
const BdrvChildRole *role,
QDict *parent_options,
int parent_flags)
BlockReopenQueueEntry *bs_entry;
BdrvChild *child;
- QDict *old_options, *explicit_options;
+ QDict *old_options, *explicit_options, *options_copy;
+ int flags;
+ QemuOpts *opts;
/* Make sure that the caller remembered to use a drained section. This is
* important to avoid graph changes between the recursive queuing here and
/*
* Precedence of options:
* 1. Explicitly passed in options (highest)
- * 2. Set in flags (only for top level)
- * 3. Retained from explicitly set options of bs
- * 4. Inherited from parent node
- * 5. Retained from effective options of bs
+ * 2. Retained from explicitly set options of bs
+ * 3. Inherited from parent node
+ * 4. Retained from effective options of bs
*/
- if (!parent_options) {
- /*
- * Any setting represented by flags is always updated. If the
- * corresponding QDict option is set, it takes precedence. Otherwise
- * the flag is translated into a QDict option. The old setting of bs is
- * not considered.
- */
- update_options_from_flags(options, flags);
- }
-
/* Old explicitly set values (don't overwrite by inherited value) */
if (bs_entry) {
old_options = qdict_clone_shallow(bs_entry->state.explicit_options);
/* Inherit from parent node */
if (parent_options) {
- QemuOpts *opts;
- QDict *options_copy;
- assert(!flags);
+ flags = 0;
role->inherit_options(&flags, options, parent_flags, parent_options);
- options_copy = qdict_clone_shallow(options);
- opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort);
- qemu_opts_absorb_qdict(opts, options_copy, NULL);
- update_flags_from_options(&flags, opts);
- qemu_opts_del(opts);
- qobject_unref(options_copy);
+ } else {
+ flags = bdrv_get_flags(bs);
}
/* Old values are used for options that aren't set yet */
bdrv_join_options(bs, options, old_options);
qobject_unref(old_options);
+ /* We have the final set of options so let's update the flags */
+ options_copy = qdict_clone_shallow(options);
+ opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort);
+ qemu_opts_absorb_qdict(opts, options_copy, NULL);
+ update_flags_from_options(&flags, opts);
+ qemu_opts_del(opts);
+ qobject_unref(options_copy);
+
/* bdrv_open_inherit() sets and clears some additional flags internally */
flags &= ~BDRV_O_PROTOCOL;
if (flags & BDRV_O_RDWR) {
qdict_extract_subqdict(options, &new_child_options, child_key_dot);
g_free(child_key_dot);
- bdrv_reopen_queue_child(bs_queue, child->bs, new_child_options, 0,
+ bdrv_reopen_queue_child(bs_queue, child->bs, new_child_options,
child->role, options, flags);
}
BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
BlockDriverState *bs,
- QDict *options, int flags)
+ QDict *options)
{
- return bdrv_reopen_queue_child(bs_queue, bs, options, flags,
- NULL, NULL, 0);
+ return bdrv_reopen_queue_child(bs_queue, bs, options, NULL, NULL, 0);
}
/*
return ret;
}
-
-/* Reopen a single BlockDriverState with the specified flags. */
-int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp)
+int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only,
+ Error **errp)
{
- int ret = -1;
- Error *local_err = NULL;
+ int ret;
BlockReopenQueue *queue;
+ QDict *opts = qdict_new();
- bdrv_subtree_drained_begin(bs);
-
- queue = bdrv_reopen_queue(NULL, bs, NULL, bdrv_flags);
- ret = bdrv_reopen_multiple(bdrv_get_aio_context(bs), queue, &local_err);
- if (local_err != NULL) {
- error_propagate(errp, local_err);
- }
+ qdict_put_bool(opts, BDRV_OPT_READ_ONLY, read_only);
+ bdrv_subtree_drained_begin(bs);
+ queue = bdrv_reopen_queue(NULL, bs, opts);
+ ret = bdrv_reopen_multiple(bdrv_get_aio_context(bs), queue, errp);
bdrv_subtree_drained_end(bs);
return ret;
Error **errp)
{
int ret = -1;
+ int old_flags;
Error *local_err = NULL;
BlockDriver *drv;
QemuOpts *opts;
QDict *orig_reopen_opts;
char *discard = NULL;
bool read_only;
+ bool drv_prepared = false;
assert(reopen_state != NULL);
assert(reopen_state->bs->drv != NULL);
goto error;
}
+ /* This was already called in bdrv_reopen_queue_child() so the flags
+ * are up-to-date. This time we simply want to remove the options from
+ * QemuOpts in order to indicate that they have been processed. */
+ old_flags = reopen_state->flags;
update_flags_from_options(&reopen_state->flags, opts);
+ assert(old_flags == reopen_state->flags);
discard = qemu_opt_get_del(opts, BDRV_OPT_DISCARD);
if (discard != NULL) {
goto error;
}
+ drv_prepared = true;
+
/* Options that are not handled are only okay if they are unchanged
* compared to the old state. It is expected that some options are only
* used for the initial open, but not reopen (e.g. filename) */
reopen_state->options = qobject_ref(orig_reopen_opts);
error:
+ if (ret < 0 && drv_prepared) {
+ /* drv->bdrv_reopen_prepare() has succeeded, so we need to
+ * call drv->bdrv_reopen_abort() before signaling an error
+ * (bdrv_reopen_multiple() will not call bdrv_reopen_abort()
+ * when the respective bdrv_reopen_prepare() has failed) */
+ if (drv->bdrv_reopen_abort) {
+ drv->bdrv_reopen_abort(reopen_state);
+ }
+ }
qemu_opts_del(opts);
qobject_unref(orig_reopen_opts);
g_free(discard);
int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base,
const char *backing_file_str)
{
+ BlockDriverState *explicit_top = top;
+ bool update_inherits_from;
BdrvChild *c, *next;
Error *local_err = NULL;
int ret = -EIO;
goto exit;
}
+ /* If 'base' recursively inherits from 'top' then we should set
+ * base->inherits_from to top->inherits_from after 'top' and all
+ * other intermediate nodes have been dropped.
+ * If 'top' is an implicit node (e.g. "commit_top") we should skip
+ * it because no one inherits from it. We use explicit_top for that. */
+ while (explicit_top && explicit_top->implicit) {
+ explicit_top = backing_bs(explicit_top);
+ }
+ update_inherits_from = bdrv_inherits_from_recursive(base, explicit_top);
+
/* 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. */
bdrv_unref(top);
}
+ if (update_inherits_from) {
+ base->inherits_from = explicit_top->inherits_from;
+ }
+
ret = 0;
exit:
bdrv_unref(top);
}
}
-static int bdrv_inactivate_recurse(BlockDriverState *bs,
- bool setting_flag)
+static bool bdrv_has_bds_parent(BlockDriverState *bs, bool only_active)
+{
+ BdrvChild *parent;
+
+ QLIST_FOREACH(parent, &bs->parents, next_parent) {
+ if (parent->role->parent_is_bds) {
+ BlockDriverState *parent_bs = parent->opaque;
+ if (!only_active || !(parent_bs->open_flags & BDRV_O_INACTIVE)) {
+ return true;
+ }
+ }
+ }
+
+ return false;
+}
+
+static int bdrv_inactivate_recurse(BlockDriverState *bs)
{
BdrvChild *child, *parent;
+ uint64_t perm, shared_perm;
int ret;
if (!bs->drv) {
return -ENOMEDIUM;
}
- if (!setting_flag && bs->drv->bdrv_inactivate) {
+ /* Make sure that we don't inactivate a child before its parent.
+ * It will be covered by recursion from the yet active parent. */
+ if (bdrv_has_bds_parent(bs, true)) {
+ return 0;
+ }
+
+ assert(!(bs->open_flags & BDRV_O_INACTIVE));
+
+ /* Inactivate this node */
+ if (bs->drv->bdrv_inactivate) {
ret = bs->drv->bdrv_inactivate(bs);
if (ret < 0) {
return ret;
}
}
- if (setting_flag && !(bs->open_flags & BDRV_O_INACTIVE)) {
- uint64_t perm, shared_perm;
-
- QLIST_FOREACH(parent, &bs->parents, next_parent) {
- if (parent->role->inactivate) {
- ret = parent->role->inactivate(parent);
- if (ret < 0) {
- return ret;
- }
+ QLIST_FOREACH(parent, &bs->parents, next_parent) {
+ if (parent->role->inactivate) {
+ ret = parent->role->inactivate(parent);
+ if (ret < 0) {
+ return ret;
}
}
+ }
- bs->open_flags |= BDRV_O_INACTIVE;
+ bs->open_flags |= BDRV_O_INACTIVE;
+
+ /* Update permissions, they may differ for inactive nodes */
+ bdrv_get_cumulative_perm(bs, &perm, &shared_perm);
+ bdrv_check_perm(bs, NULL, perm, shared_perm, NULL, &error_abort);
+ bdrv_set_perm(bs, perm, shared_perm);
- /* Update permissions, they may differ for inactive nodes */
- bdrv_get_cumulative_perm(bs, &perm, &shared_perm);
- bdrv_check_perm(bs, NULL, perm, shared_perm, NULL, &error_abort);
- bdrv_set_perm(bs, perm, shared_perm);
- }
+ /* Recursively inactivate children */
QLIST_FOREACH(child, &bs->children, next) {
- ret = bdrv_inactivate_recurse(child->bs, setting_flag);
+ ret = bdrv_inactivate_recurse(child->bs);
if (ret < 0) {
return ret;
}
BlockDriverState *bs = NULL;
BdrvNextIterator it;
int ret = 0;
- int pass;
GSList *aio_ctxs = NULL, *ctx;
for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
}
}
- /* We do two passes of inactivation. The first pass calls to drivers'
- * .bdrv_inactivate callbacks recursively so all cache is flushed to disk;
- * the second pass sets the BDRV_O_INACTIVE flag so that no further write
- * is allowed. */
- for (pass = 0; pass < 2; pass++) {
- 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;
- }
+ for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
+ /* Nodes with BDS parents are covered by recursion from the last
+ * parent that gets inactivated. Don't inactivate them a second
+ * time if that has already happened. */
+ if (bdrv_has_bds_parent(bs, false)) {
+ continue;
+ }
+ ret = bdrv_inactivate_recurse(bs);
+ if (ret < 0) {
+ bdrv_next_cleanup(&it);
+ goto out;
}
}
projects / qemu.git / blobdiff