On Thu, 12/12 16:33, Benoît Canet wrote:
> Add the minimum of code to prepare for the following patches.
>
> Signed-off-by: Benoit Canet <ben...@irqsave.net>
> ---
> block.c | 57
> +++++++++++++++++++++++++++++++++++------------
> include/block/block.h | 1 +
> include/block/block_int.h | 9 +++++++-
> 3 files changed, 52 insertions(+), 15 deletions(-)
>
> diff --git a/block.c b/block.c
> index 64e7d22..481d566 100644
> --- a/block.c
> +++ b/block.c
> @@ -90,6 +90,9 @@ static int coroutine_fn
> bdrv_co_do_write_zeroes(BlockDriverState *bs,
> static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
> QTAILQ_HEAD_INITIALIZER(bdrv_states);
>
> +static QTAILQ_HEAD(, BlockDriverState) graph_bdrv_states =
> + QTAILQ_HEAD_INITIALIZER(graph_bdrv_states);
> +
> static QLIST_HEAD(, BlockDriver) bdrv_drivers =
> QLIST_HEAD_INITIALIZER(bdrv_drivers);
>
> @@ -327,7 +330,7 @@ BlockDriverState *bdrv_new(const char *device_name)
> QLIST_INIT(&bs->dirty_bitmaps);
> pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
> if (device_name[0] != '\0') {
> - QTAILQ_INSERT_TAIL(&bdrv_states, bs, list);
> + QTAILQ_INSERT_TAIL(&bdrv_states, bs, device_list);
> }
> bdrv_iostatus_disable(bs);
> notifier_list_init(&bs->close_notifiers);
> @@ -1501,7 +1504,7 @@ void bdrv_close_all(void)
> {
> BlockDriverState *bs;
>
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> bdrv_close(bs);
> }
> }
> @@ -1530,7 +1533,7 @@ static bool bdrv_requests_pending(BlockDriverState *bs)
> static bool bdrv_requests_pending_all(void)
> {
> BlockDriverState *bs;
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> if (bdrv_requests_pending(bs)) {
> return true;
> }
> @@ -1557,7 +1560,7 @@ void bdrv_drain_all(void)
> BlockDriverState *bs;
>
> while (busy) {
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> bdrv_start_throttled_reqs(bs);
> }
>
> @@ -1566,14 +1569,19 @@ void bdrv_drain_all(void)
> }
> }
>
> -/* make a BlockDriverState anonymous by removing from bdrv_state list.
> +/* make a BlockDriverState anonymous by removing from bdrv_state and
> + * graph_bdrv_state list.
> Also, NULL terminate the device_name to prevent double remove */
> void bdrv_make_anon(BlockDriverState *bs)
> {
> if (bs->device_name[0] != '\0') {
> - QTAILQ_REMOVE(&bdrv_states, bs, list);
> + QTAILQ_REMOVE(&bdrv_states, bs, device_list);
> }
> bs->device_name[0] = '\0';
> + if (bs->node_name[0] != '\0') {
> + QTAILQ_REMOVE(&graph_bdrv_states, bs, node_list);
> + }
> + bs->node_name[0] = '\0';
> }
>
> static void bdrv_rebind(BlockDriverState *bs)
> @@ -1627,7 +1635,12 @@ static void bdrv_move_feature_fields(BlockDriverState
> *bs_dest,
> /* keep the same entry in bdrv_states */
> pstrcpy(bs_dest->device_name, sizeof(bs_dest->device_name),
> bs_src->device_name);
> - bs_dest->list = bs_src->list;
> + bs_dest->device_list = bs_src->device_list;
> +
> + /* keep the same entry in graph_bdrv_states
> + * We do want to swap name but don't want to swap linked list entries
> + */
> + bs_dest->node_list = bs_src->node_list;
> }
>
> /*
> @@ -1952,7 +1965,7 @@ int bdrv_commit_all(void)
> {
> BlockDriverState *bs;
>
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> if (bs->drv && bs->backing_hd) {
> int ret = bdrv_commit(bs);
> if (ret < 0) {
> @@ -3110,11 +3123,12 @@ void bdrv_iterate_format(void (*it)(void *opaque,
> const char *name),
> }
> }
>
> +/* This function is to find block backend bs */
> BlockDriverState *bdrv_find(const char *name)
> {
> BlockDriverState *bs;
>
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> if (!strcmp(name, bs->device_name)) {
> return bs;
> }
> @@ -3122,19 +3136,34 @@ BlockDriverState *bdrv_find(const char *name)
> return NULL;
> }
>
> +/* This function is to find a node in the bs graph */
> +BlockDriverState *bdrv_find_node(const char *node_name)
> +{
> + BlockDriverState *bs;
> +
> + assert(node_name);
> +
> + QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) {
> + if (!strcmp(node_name, bs->node_name)) {
> + return bs;
> + }
> + }
> + return NULL;
> +}
> +
> BlockDriverState *bdrv_next(BlockDriverState *bs)
> {
> if (!bs) {
> return QTAILQ_FIRST(&bdrv_states);
> }
> - return QTAILQ_NEXT(bs, list);
> + return QTAILQ_NEXT(bs, device_list);
> }
>
> void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void
> *opaque)
> {
> BlockDriverState *bs;
>
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> it(opaque, bs);
> }
> }
> @@ -3154,7 +3183,7 @@ int bdrv_flush_all(void)
> BlockDriverState *bs;
> int result = 0;
>
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> int ret = bdrv_flush(bs);
> if (ret < 0 && !result) {
> result = ret;
> @@ -4278,7 +4307,7 @@ void bdrv_invalidate_cache_all(void)
> {
> BlockDriverState *bs;
>
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> bdrv_invalidate_cache(bs);
> }
> }
> @@ -4287,7 +4316,7 @@ void bdrv_clear_incoming_migration_all(void)
> {
> BlockDriverState *bs;
>
> - QTAILQ_FOREACH(bs, &bdrv_states, list) {
> + QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
> bs->open_flags = bs->open_flags & ~(BDRV_O_INCOMING);
> }
> }
> diff --git a/include/block/block.h b/include/block/block.h
> index 36efaea..834abf9 100644
> --- a/include/block/block.h
> +++ b/include/block/block.h
> @@ -374,6 +374,7 @@ void bdrv_lock_medium(BlockDriverState *bs, bool locked);
> void bdrv_eject(BlockDriverState *bs, bool eject_flag);
> const char *bdrv_get_format_name(BlockDriverState *bs);
> BlockDriverState *bdrv_find(const char *name);
> +BlockDriverState *bdrv_find_node(const char *node_name);
> BlockDriverState *bdrv_next(BlockDriverState *bs);
> void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs),
> void *opaque);
> diff --git a/include/block/block_int.h b/include/block/block_int.h
> index 8b132d7..bd5220f 100644
> --- a/include/block/block_int.h
> +++ b/include/block/block_int.h
> @@ -325,11 +325,18 @@ struct BlockDriverState {
> BlockdevOnError on_read_error, on_write_error;
> bool iostatus_enabled;
> BlockDeviceIoStatus iostatus;
> +
> + /* the following member gives a name to every node on the bs graph. */
> + char node_name[32];
> + /* element of the list of named nodes building the graph */
> + QTAILQ_ENTRY(BlockDriverState) node_list;
> + /* Device name is the name associated with the "drive" the guest sees */
> char device_name[32];
> + /* element of the list of "drives" the guest sees */
> + QTAILQ_ENTRY(BlockDriverState) device_list;
> QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
> int refcnt;
> int in_use; /* users other than guest access, eg. block migration */
> - QTAILQ_ENTRY(BlockDriverState) list;
>
> QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
>
> --
> 1.8.3.2
>
>
Reviewed-by: Fam Zheng <f...@redhat.com>
