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Diffstat (limited to 'block')
-rw-r--r--block/block-backend.c72
-rw-r--r--block/io.c13
-rw-r--r--block/snapshot.c30
3 files changed, 75 insertions, 40 deletions
diff --git a/block/block-backend.c b/block/block-backend.c
index 9dcac9792f..7f2eeb0559 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -75,6 +75,7 @@ static const AIOCBInfo block_backend_aiocb_info = {
};
static void drive_info_del(DriveInfo *dinfo);
+static BlockBackend *bdrv_first_blk(BlockDriverState *bs);
/* All BlockBackends */
static QTAILQ_HEAD(, BlockBackend) block_backends =
@@ -286,28 +287,50 @@ BlockBackend *blk_next(BlockBackend *blk)
: QTAILQ_FIRST(&monitor_block_backends);
}
-/*
- * Iterates over all BlockDriverStates which are attached to a BlockBackend.
- * This function is for use by bdrv_next().
- *
- * @bs must be NULL or a BDS that is attached to a BB.
- */
-BlockDriverState *blk_next_root_bs(BlockDriverState *bs)
-{
+struct BdrvNextIterator {
+ enum {
+ BDRV_NEXT_BACKEND_ROOTS,
+ BDRV_NEXT_MONITOR_OWNED,
+ } phase;
BlockBackend *blk;
+ BlockDriverState *bs;
+};
- if (bs) {
- assert(bs->blk);
- blk = bs->blk;
- } else {
- blk = NULL;
+/* Iterates over all top-level BlockDriverStates, i.e. BDSs that are owned by
+ * the monitor or attached to a BlockBackend */
+BdrvNextIterator *bdrv_next(BdrvNextIterator *it, BlockDriverState **bs)
+{
+ if (!it) {
+ it = g_new(BdrvNextIterator, 1);
+ *it = (BdrvNextIterator) {
+ .phase = BDRV_NEXT_BACKEND_ROOTS,
+ };
+ }
+
+ /* First, return all root nodes of BlockBackends. In order to avoid
+ * returning a BDS twice when multiple BBs refer to it, we only return it
+ * if the BB is the first one in the parent list of the BDS. */
+ if (it->phase == BDRV_NEXT_BACKEND_ROOTS) {
+ do {
+ it->blk = blk_all_next(it->blk);
+ *bs = it->blk ? blk_bs(it->blk) : NULL;
+ } while (it->blk && (*bs == NULL || bdrv_first_blk(*bs) != it->blk));
+
+ if (*bs) {
+ return it;
+ }
+ it->phase = BDRV_NEXT_MONITOR_OWNED;
}
+ /* Then return the monitor-owned BDSes without a BB attached. Ignore all
+ * BDSes that are attached to a BlockBackend here; they have been handled
+ * by the above block already */
do {
- blk = blk_all_next(blk);
- } while (blk && !blk->root);
+ it->bs = bdrv_next_monitor_owned(it->bs);
+ *bs = it->bs;
+ } while (*bs && bdrv_has_blk(*bs));
- return blk ? blk->root->bs : NULL;
+ return *bs ? it : NULL;
}
/*
@@ -394,21 +417,26 @@ BlockDriverState *blk_bs(BlockBackend *blk)
return blk->root ? blk->root->bs : NULL;
}
-/*
- * Returns true if @bs has an associated BlockBackend.
- */
-bool bdrv_has_blk(BlockDriverState *bs)
+static BlockBackend *bdrv_first_blk(BlockDriverState *bs)
{
BdrvChild *child;
QLIST_FOREACH(child, &bs->parents, next_parent) {
if (child->role == &child_root) {
assert(bs->blk);
- return true;
+ return child->opaque;
}
}
assert(!bs->blk);
- return false;
+ return NULL;
+}
+
+/*
+ * Returns true if @bs has an associated BlockBackend.
+ */
+bool bdrv_has_blk(BlockDriverState *bs)
+{
+ return bdrv_first_blk(bs) != NULL;
}
/*
diff --git a/block/io.c b/block/io.c
index 8a6f470478..60a6bd8bdb 100644
--- a/block/io.c
+++ b/block/io.c
@@ -270,10 +270,11 @@ void bdrv_drain_all(void)
{
/* Always run first iteration so any pending completion BHs run */
bool busy = true;
- BlockDriverState *bs = NULL;
+ BlockDriverState *bs;
+ BdrvNextIterator *it = NULL;
GSList *aio_ctxs = NULL, *ctx;
- while ((bs = bdrv_next(bs))) {
+ while ((it = bdrv_next(it, &bs))) {
AioContext *aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
@@ -301,10 +302,10 @@ void bdrv_drain_all(void)
for (ctx = aio_ctxs; ctx != NULL; ctx = ctx->next) {
AioContext *aio_context = ctx->data;
- bs = NULL;
+ it = NULL;
aio_context_acquire(aio_context);
- while ((bs = bdrv_next(bs))) {
+ while ((it = bdrv_next(it, &bs))) {
if (aio_context == bdrv_get_aio_context(bs)) {
if (bdrv_requests_pending(bs)) {
busy = true;
@@ -317,8 +318,8 @@ void bdrv_drain_all(void)
}
}
- bs = NULL;
- while ((bs = bdrv_next(bs))) {
+ it = NULL;
+ while ((it = bdrv_next(it, &bs))) {
AioContext *aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
diff --git a/block/snapshot.c b/block/snapshot.c
index e9d721df68..3917ec5c91 100644
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -373,9 +373,10 @@ int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs,
bool bdrv_all_can_snapshot(BlockDriverState **first_bad_bs)
{
bool ok = true;
- BlockDriverState *bs = NULL;
+ BlockDriverState *bs;
+ BdrvNextIterator *it = NULL;
- while (ok && (bs = bdrv_next(bs))) {
+ while (ok && (it = bdrv_next(it, &bs))) {
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
@@ -393,10 +394,11 @@ int bdrv_all_delete_snapshot(const char *name, BlockDriverState **first_bad_bs,
Error **err)
{
int ret = 0;
- BlockDriverState *bs = NULL;
+ BlockDriverState *bs;
+ BdrvNextIterator *it = NULL;
QEMUSnapshotInfo sn1, *snapshot = &sn1;
- while (ret == 0 && (bs = bdrv_next(bs))) {
+ while (ret == 0 && (it = bdrv_next(it, &bs))) {
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
@@ -415,9 +417,10 @@ int bdrv_all_delete_snapshot(const char *name, BlockDriverState **first_bad_bs,
int bdrv_all_goto_snapshot(const char *name, BlockDriverState **first_bad_bs)
{
int err = 0;
- BlockDriverState *bs = NULL;
+ BlockDriverState *bs;
+ BdrvNextIterator *it = NULL;
- while (err == 0 && (bs = bdrv_next(bs))) {
+ while (err == 0 && (it = bdrv_next(it, &bs))) {
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
@@ -435,9 +438,10 @@ int bdrv_all_find_snapshot(const char *name, BlockDriverState **first_bad_bs)
{
QEMUSnapshotInfo sn;
int err = 0;
- BlockDriverState *bs = NULL;
+ BlockDriverState *bs;
+ BdrvNextIterator *it = NULL;
- while (err == 0 && (bs = bdrv_next(bs))) {
+ while (err == 0 && (it = bdrv_next(it, &bs))) {
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
@@ -457,9 +461,10 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
BlockDriverState **first_bad_bs)
{
int err = 0;
- BlockDriverState *bs = NULL;
+ BlockDriverState *bs;
+ BdrvNextIterator *it = NULL;
- while (err == 0 && (bs = bdrv_next(bs))) {
+ while (err == 0 && (it = bdrv_next(it, &bs))) {
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
@@ -480,9 +485,10 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
BlockDriverState *bdrv_all_find_vmstate_bs(void)
{
bool not_found = true;
- BlockDriverState *bs = NULL;
+ BlockDriverState *bs;
+ BdrvNextIterator *it = NULL;
- while (not_found && (bs = bdrv_next(bs))) {
+ while (not_found && (it = bdrv_next(it, &bs))) {
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-24 05:20:19 +0000