[Qemu-devel] [PATCH 09/17] block: Add .bdrv_co_pdiscard() driver callback

[Eric Blake <eblake@redhat.com>]

There's enough drivers with a sector-based callback that it will
be easier to switch one at a time.  This patch adds a byte-based
callback, and then after all drivers are swapped, we'll drop the
sector-based callback.

[checkpatch doesn't like the space after coroutine_fn in
block_int.h, but it's consistent with the rest of the file]

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 include/block/block_int.h | 2 ++
 block/io.c                | 7 +++++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/include/block/block_int.h b/include/block/block_int.h
index 880a6d8..61e5b5a 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -167,6 +167,8 @@ struct BlockDriver {
         int64_t offset, int count, BdrvRequestFlags flags);
     int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs,
         int64_t sector_num, int nb_sectors);
+    int coroutine_fn (*bdrv_co_pdiscard)(BlockDriverState *bs,
+        int64_t offset, int count);
     int64_t coroutine_fn (*bdrv_co_get_block_status)(BlockDriverState *bs,
         int64_t sector_num, int nb_sectors, int *pnum,
         BlockDriverState **file);
diff --git a/block/io.c b/block/io.c
index d8dc014..9d1f36d 100644
--- a/block/io.c
+++ b/block/io.c
@@ -2394,7 +2394,8 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset,
         return 0;
     }

-    if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_aio_pdiscard) {
+    if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_co_pdiscard &&
+        !bs->drv->bdrv_aio_pdiscard) {
         return 0;
     }

@@ -2426,7 +2427,9 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset,
         int ret;
         int num = MIN(count, max_pdiscard);

-        if (bs->drv->bdrv_co_discard) {
+        if (bs->drv->bdrv_co_pdiscard) {
+            ret = bs->drv->bdrv_co_pdiscard(bs, offset, num);
+        } else if (bs->drv->bdrv_co_discard) {
             ret = bs->drv->bdrv_co_discard(bs, offset >> BDRV_SECTOR_BITS,
                                            num >> BDRV_SECTOR_BITS);
         } else {
-- 
2.5.5