#include "qmp-commands.h"
#include "qemu/timer.h"
#include "qapi-event.h"
-#include "block/throttle-groups.h"
#include "qemu/cutils.h"
#include "qemu/id.h"
void bdrv_register(BlockDriver *bdrv)
{
- bdrv_setup_io_funcs(bdrv);
-
QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list);
}
QLIST_INIT(&bs->op_blockers[i]);
}
notifier_with_return_list_init(&bs->before_write_notifiers);
- qemu_co_queue_init(&bs->throttled_reqs[0]);
- qemu_co_queue_init(&bs->throttled_reqs[1]);
bs->refcnt = 1;
bs->aio_context = qemu_get_aio_context();
*
* Return 0 on success, -1 if the cache mode was invalid.
*/
-int bdrv_parse_cache_flags(const char *mode, int *flags)
+int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough)
{
*flags &= ~BDRV_O_CACHE_MASK;
if (!strcmp(mode, "off") || !strcmp(mode, "none")) {
- *flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
+ *writethrough = false;
+ *flags |= BDRV_O_NOCACHE;
} else if (!strcmp(mode, "directsync")) {
+ *writethrough = true;
*flags |= BDRV_O_NOCACHE;
} else if (!strcmp(mode, "writeback")) {
- *flags |= BDRV_O_CACHE_WB;
+ *writethrough = false;
} else if (!strcmp(mode, "unsafe")) {
- *flags |= BDRV_O_CACHE_WB;
+ *writethrough = false;
*flags |= BDRV_O_NO_FLUSH;
} else if (!strcmp(mode, "writethrough")) {
- /* this is the default */
+ *writethrough = true;
} else {
return -1;
}
return 0;
}
-int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough)
-{
- int ret = bdrv_parse_cache_flags(mode, flags);
- if (ret < 0) {
- return ret;
- }
-
- if (*flags & BDRV_O_CACHE_WB) {
- *flags &= ~BDRV_O_CACHE_WB;
- *writethrough = false;
- } else {
- *writethrough = true;
- }
-
- return 0;
-}
-
/*
* Returns the options and flags that a temporary snapshot should get, based on
* the originally requested flags (the originally requested image will have
*child_flags = (parent_flags & ~BDRV_O_SNAPSHOT) | BDRV_O_TEMPORARY;
/* For temporary files, unconditional cache=unsafe is fine */
- qdict_set_default_str(child_options, BDRV_OPT_CACHE_WB, "on");
qdict_set_default_str(child_options, BDRV_OPT_CACHE_DIRECT, "off");
qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on");
}
/* Our block drivers take care to send flushes and respect unmap policy,
* so we can default to enable both on lower layers regardless of the
* corresponding parent options. */
- qdict_set_default_str(child_options, BDRV_OPT_CACHE_WB, "on");
flags |= BDRV_O_UNMAP;
/* Clear flags that only apply to the top layer */
/* The cache mode is inherited unmodified for backing files; except WCE,
* which is only applied on the top level (BlockBackend) */
- qdict_set_default_str(child_options, BDRV_OPT_CACHE_WB, "on");
qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIRECT);
qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FLUSH);
static int bdrv_open_flags(BlockDriverState *bs, int flags)
{
- int open_flags = flags | BDRV_O_CACHE_WB;
+ int open_flags = flags;
/*
* Clear flags that are internal to the block layer before opening the
{
*flags &= ~BDRV_O_CACHE_MASK;
- assert(qemu_opt_find(opts, BDRV_OPT_CACHE_WB));
- if (qemu_opt_get_bool(opts, BDRV_OPT_CACHE_WB, false)) {
- *flags |= BDRV_O_CACHE_WB;
- }
-
assert(qemu_opt_find(opts, BDRV_OPT_CACHE_NO_FLUSH));
if (qemu_opt_get_bool(opts, BDRV_OPT_CACHE_NO_FLUSH, false)) {
*flags |= BDRV_O_NO_FLUSH;
static void update_options_from_flags(QDict *options, int flags)
{
- if (!qdict_haskey(options, BDRV_OPT_CACHE_WB)) {
- qdict_put(options, BDRV_OPT_CACHE_WB,
- qbool_from_bool(flags & BDRV_O_CACHE_WB));
- }
if (!qdict_haskey(options, BDRV_OPT_CACHE_DIRECT)) {
qdict_put(options, BDRV_OPT_CACHE_DIRECT,
qbool_from_bool(flags & BDRV_O_NOCACHE));
.type = QEMU_OPT_STRING,
.help = "Block driver to use for the node",
},
- {
- .name = BDRV_OPT_CACHE_WB,
- .type = QEMU_OPT_BOOL,
- .help = "Enable writeback mode",
- },
{
.name = BDRV_OPT_CACHE_DIRECT,
.type = QEMU_OPT_BOOL,
/* Apply cache mode options */
update_flags_from_options(&bs->open_flags, opts);
- if (!bs->blk && (bs->open_flags & BDRV_O_CACHE_WB) == 0) {
- error_setg(errp, "Can't set writethrough mode except for the root");
- ret = -EINVAL;
- goto free_and_fail;
- }
-
- bdrv_set_enable_write_cache(bs, bs->open_flags & BDRV_O_CACHE_WB);
-
/* Open the image, either directly or using a protocol */
open_flags = bdrv_open_flags(bs, bs->open_flags);
if (drv->bdrv_file_open) {
return child;
}
-static BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
- BlockDriverState *child_bs,
- const char *child_name,
- const BdrvChildRole *child_role)
+BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
+ BlockDriverState *child_bs,
+ const char *child_name,
+ const BdrvChildRole *child_role)
{
BdrvChild *child = bdrv_root_attach_child(child_bs, child_name, child_role);
QLIST_INSERT_HEAD(&parent_bs->children, child, next);
bdrv_root_unref_child(child);
}
+
+static void bdrv_parent_cb_change_media(BlockDriverState *bs, bool load)
+{
+ BdrvChild *c;
+ QLIST_FOREACH(c, &bs->parents, next_parent) {
+ if (c->role->change_media) {
+ c->role->change_media(c, load);
+ }
+ }
+}
+
+static void bdrv_parent_cb_resize(BlockDriverState *bs)
+{
+ BdrvChild *c;
+ QLIST_FOREACH(c, &bs->parents, next_parent) {
+ if (c->role->resize) {
+ c->role->resize(c);
+ }
+ }
+}
+
/*
* 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().
if (!bs) {
return -ENODEV;
}
+
bdrv_ref(bs);
*pbs = bs;
return 0;
}
if (!bdrv_key_required(bs)) {
- if (bs->blk) {
- blk_dev_change_media_cb(bs->blk, true);
- }
+ bdrv_parent_cb_change_media(bs, true);
} else if (!runstate_check(RUN_STATE_PRELAUNCH)
&& !runstate_check(RUN_STATE_INMIGRATE)
&& !runstate_check(RUN_STATE_PAUSED)) { /* HACK */
update_flags_from_options(&reopen_state->flags, opts);
- /* WCE is a BlockBackend level option, can't change it */
- bool old_wce = bdrv_enable_write_cache(reopen_state->bs);
- bool new_wce = (reopen_state->flags & BDRV_O_CACHE_WB);
-
- if (old_wce != new_wce) {
- error_setg(errp, "Cannot change cache.writeback");
- ret = -EINVAL;
- goto error;
- }
-
/* node-name and driver must be unchanged. Put them back into the QDict, so
* that they are checked at the end of this function. */
value = qemu_opt_get(opts, "node-name");
reopen_state->bs->open_flags = reopen_state->flags;
reopen_state->bs->read_only = !(reopen_state->flags & BDRV_O_RDWR);
- bdrv_set_enable_write_cache(reopen_state->bs,
- !!(reopen_state->flags & BDRV_O_CACHE_WB));
bdrv_refresh_limits(reopen_state->bs, NULL);
}
assert(!bs->job);
- /* Disable I/O limits and drain all pending throttled requests */
- if (bs->throttle_state) {
- bdrv_io_limits_disable(bs);
- }
-
bdrv_drained_begin(bs); /* complete I/O */
bdrv_flush(bs);
bdrv_drain(bs); /* in case flush left pending I/O */
bdrv_release_named_dirty_bitmaps(bs);
assert(QLIST_EMPTY(&bs->dirty_bitmaps));
- if (bs->blk) {
- blk_dev_change_media_cb(bs->blk, false);
- }
+ bdrv_parent_cb_change_media(bs, false);
if (bs->drv) {
BdrvChild *child, *next;
}
}
-/* Fields that need to stay with the top-level BDS */
-static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
- BlockDriverState *bs_src)
-{
- /* move some fields that need to stay attached to the device */
-}
-
static void change_parent_backing_link(BlockDriverState *from,
BlockDriverState *to)
{
}
}
-static void swap_feature_fields(BlockDriverState *bs_top,
- BlockDriverState *bs_new)
-{
- BlockDriverState tmp;
-
- bdrv_move_feature_fields(&tmp, bs_top);
- bdrv_move_feature_fields(bs_top, bs_new);
- bdrv_move_feature_fields(bs_new, &tmp);
-
- assert(!bs_new->throttle_state);
- if (bs_top->throttle_state) {
- assert(bs_top->io_limits_enabled);
- bdrv_io_limits_enable(bs_new, throttle_group_get_name(bs_top));
- bdrv_io_limits_disable(bs_top);
- }
-}
-
/*
* Add new bs contents at the top of an image chain while the chain is
* live, while keeping required fields on the top layer.
assert(!bdrv_requests_pending(bs_new));
bdrv_ref(bs_top);
- change_parent_backing_link(bs_top, bs_new);
-
- /* Some fields always stay on top of the backing file chain */
- swap_feature_fields(bs_top, bs_new);
+ change_parent_backing_link(bs_top, bs_new);
bdrv_set_backing_hd(bs_new, bs_top);
bdrv_unref(bs_top);
bdrv_ref(old);
- if (old->blk) {
- /* As long as these fields aren't in BlockBackend, but in the top-level
- * BlockDriverState, it's not possible for a BDS to have two BBs.
- *
- * We really want to copy the fields from old to new, but we go for a
- * swap instead so that pointers aren't duplicated and cause trouble.
- * (Also, bdrv_swap() used to do the same.) */
- assert(!new->blk);
- swap_feature_fields(old, new);
- }
change_parent_backing_link(old, new);
/* Change backing files if a previously independent node is added to the
if (ret == 0) {
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
bdrv_dirty_bitmap_truncate(bs);
- if (bs->blk) {
- blk_dev_resize_cb(bs->blk);
- }
+ bdrv_parent_cb_resize(bs);
}
return ret;
}
return bs->sg;
}
-int bdrv_enable_write_cache(BlockDriverState *bs)
-{
- if (bs->blk) {
- return blk_enable_write_cache(bs->blk);
- } else {
- return true;
- }
-}
-
-void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce)
-{
- if (bs->blk) {
- blk_set_enable_write_cache(bs->blk, wce);
- }
-
- /* so a reopen() will preserve wce */
- if (wce) {
- bs->open_flags |= BDRV_O_CACHE_WB;
- } else {
- bs->open_flags &= ~BDRV_O_CACHE_WB;
- }
-}
-
int bdrv_is_encrypted(BlockDriverState *bs)
{
if (bs->backing && bs->backing->bs->encrypted) {
if (ret < 0) {
bs->valid_key = 0;
} else if (!bs->valid_key) {
+ /* call the change callback now, we skipped it on open */
bs->valid_key = 1;
- if (bs->blk) {
- /* call the change callback now, we skipped it on open */
- blk_dev_change_media_cb(bs->blk, true);
- }
+ bdrv_parent_cb_change_media(bs, true);
}
return ret;
}
return bs->node_name;
}
+static const char *bdrv_get_parent_name(const BlockDriverState *bs)
+{
+ BdrvChild *c;
+ const char *name;
+
+ /* If multiple parents have a name, just pick the first one. */
+ QLIST_FOREACH(c, &bs->parents, next_parent) {
+ if (c->role->get_name) {
+ name = c->role->get_name(c);
+ if (name && *name) {
+ return name;
+ }
+ }
+ }
+
+ return NULL;
+}
+
/* TODO check what callers really want: bs->node_name or blk_name() */
const char *bdrv_get_device_name(const BlockDriverState *bs)
{
- return bs->blk ? blk_name(bs->blk) : "";
+ return bdrv_get_parent_name(bs) ?: "";
}
/* This can be used to identify nodes that might not have a device
* absent, then this returns an empty (non-null) string. */
const char *bdrv_get_device_or_node_name(const BlockDriverState *bs)
{
- return bs->blk ? blk_name(bs->blk) : bs->node_name;
+ return bdrv_get_parent_name(bs) ?: bs->node_name;
}
int bdrv_get_flags(BlockDriverState *bs)
void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
{
+ BdrvChild *child;
Error *local_err = NULL;
int ret;
if (bs->drv->bdrv_invalidate_cache) {
bs->drv->bdrv_invalidate_cache(bs, &local_err);
- } else if (bs->file) {
- bdrv_invalidate_cache(bs->file->bs, &local_err);
+ if (local_err) {
+ bs->open_flags |= BDRV_O_INACTIVE;
+ error_propagate(errp, local_err);
+ return;
+ }
}
- if (local_err) {
- bs->open_flags |= BDRV_O_INACTIVE;
- error_propagate(errp, local_err);
- return;
+
+ QLIST_FOREACH(child, &bs->children, next) {
+ bdrv_invalidate_cache(child->bs, &local_err);
+ if (local_err) {
+ bs->open_flags |= BDRV_O_INACTIVE;
+ error_propagate(errp, local_err);
+ return;
+ }
}
ret = refresh_total_sectors(bs, bs->total_sectors);
}
}
-static int bdrv_inactivate(BlockDriverState *bs)
+static int bdrv_inactivate_recurse(BlockDriverState *bs,
+ bool setting_flag)
{
+ BdrvChild *child;
int ret;
- if (bs->drv->bdrv_inactivate) {
+ if (!setting_flag && bs->drv->bdrv_inactivate) {
ret = bs->drv->bdrv_inactivate(bs);
if (ret < 0) {
return ret;
}
}
- bs->open_flags |= BDRV_O_INACTIVE;
+ QLIST_FOREACH(child, &bs->children, next) {
+ ret = bdrv_inactivate_recurse(child->bs, setting_flag);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ if (setting_flag) {
+ bs->open_flags |= BDRV_O_INACTIVE;
+ }
return 0;
}
int bdrv_inactivate_all(void)
{
BlockDriverState *bs = NULL;
- int ret;
+ int ret = 0;
+ int pass;
while ((bs = bdrv_next(bs)) != NULL) {
- AioContext *aio_context = bdrv_get_aio_context(bs);
+ aio_context_acquire(bdrv_get_aio_context(bs));
+ }
- aio_context_acquire(aio_context);
- ret = bdrv_inactivate(bs);
- aio_context_release(aio_context);
- if (ret < 0) {
- return ret;
+ /* 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++) {
+ bs = NULL;
+ while ((bs = bdrv_next(bs)) != NULL) {
+ ret = bdrv_inactivate_recurse(bs, pass);
+ if (ret < 0) {
+ goto out;
+ }
}
}
- return 0;
+out:
+ bs = NULL;
+ while ((bs = bdrv_next(bs)) != NULL) {
+ aio_context_release(bdrv_get_aio_context(bs));
+ }
+
+ return ret;
}
/**************************************************************/
}
/* backing files always opened read-only */
- back_flags = flags | BDRV_O_CACHE_WB;
+ back_flags = flags;
back_flags &= ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
if (backing_fmt) {
baf->detach_aio_context(baf->opaque);
}
- if (bs->throttle_state) {
- throttle_timers_detach_aio_context(&bs->throttle_timers);
- }
if (bs->drv->bdrv_detach_aio_context) {
bs->drv->bdrv_detach_aio_context(bs);
}
if (bs->drv->bdrv_attach_aio_context) {
bs->drv->bdrv_attach_aio_context(bs, new_context);
}
- if (bs->throttle_state) {
- throttle_timers_attach_aio_context(&bs->throttle_timers, new_context);
- }
QLIST_FOREACH(ban, &bs->aio_notifiers, list) {
ban->attached_aio_context(new_context, ban->opaque);
QDECREF(json);
}
}
+
+/*
+ * Hot add/remove a BDS's child. So the user can take a child offline when
+ * it is broken and take a new child online
+ */
+void bdrv_add_child(BlockDriverState *parent_bs, BlockDriverState *child_bs,
+ Error **errp)
+{
+
+ if (!parent_bs->drv || !parent_bs->drv->bdrv_add_child) {
+ error_setg(errp, "The node %s does not support adding a child",
+ bdrv_get_device_or_node_name(parent_bs));
+ return;
+ }
+
+ if (!QLIST_EMPTY(&child_bs->parents)) {
+ error_setg(errp, "The node %s already has a parent",
+ child_bs->node_name);
+ return;
+ }
+
+ parent_bs->drv->bdrv_add_child(parent_bs, child_bs, errp);
+}
+
+void bdrv_del_child(BlockDriverState *parent_bs, BdrvChild *child, Error **errp)
+{
+ BdrvChild *tmp;
+
+ if (!parent_bs->drv || !parent_bs->drv->bdrv_del_child) {
+ error_setg(errp, "The node %s does not support removing a child",
+ bdrv_get_device_or_node_name(parent_bs));
+ return;
+ }
+
+ QLIST_FOREACH(tmp, &parent_bs->children, next) {
+ if (tmp == child) {
+ break;
+ }
+ }
+
+ if (!tmp) {
+ error_setg(errp, "The node %s does not have a child named %s",
+ bdrv_get_device_or_node_name(parent_bs),
+ bdrv_get_device_or_node_name(child->bs));
+ return;
+ }
+
+ parent_bs->drv->bdrv_del_child(parent_bs, child, errp);
+}
projects / mirror_qemu.git / blobdiff