bdrv_is_allocated can detect coroutine context and go through a fast
path, similar to other block layer functions.
Reviewed-by: Eric Blake <ebl...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
block.c | 24 +++++++++++++++---------
block/backup.c | 4 ++--
block/raw_bsd.c | 2 +-
block/stream.c | 4 ++--
include/block/block.h | 2 --
5 files changed, 20 insertions(+), 16 deletions(-)
diff --git a/block.c b/block.c
index d5800fc..0e95b47 100644
--- a/block.c
+++ b/block.c
@@ -2559,7 +2559,7 @@ static int coroutine_fn bdrv_co_do_readv(BlockDriverState
*bs,
if (flags & BDRV_REQ_COPY_ON_READ) {
int pnum;
- ret = bdrv_co_is_allocated(bs, sector_num, nb_sectors, &pnum);
+ ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum);
if (ret < 0) {
goto out;
}
@@ -3041,8 +3041,9 @@ typedef struct BdrvCoIsAllocatedData {
* 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes
* beyond the end of the disk image it will be clamped.
*/
-int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, int *pnum)
+static int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs,
+ int64_t sector_num,
+ int nb_sectors, int *pnum)
{
int64_t n;
@@ -3092,10 +3093,15 @@ int bdrv_is_allocated(BlockDriverState *bs, int64_t
sector_num, int nb_sectors,
.done = false,
};
- co = qemu_coroutine_create(bdrv_is_allocated_co_entry);
- qemu_coroutine_enter(co, &data);
- while (!data.done) {
- qemu_aio_wait();
+ if (qemu_in_coroutine()) {
+ /* Fast-path if already in coroutine context */
+ bdrv_is_allocated_co_entry(&data);
+ } else {
+ co = qemu_coroutine_create(bdrv_is_allocated_co_entry);
+ qemu_coroutine_enter(co, &data);
+ while (!data.done) {
+ qemu_aio_wait();
+ }
}
return data.ret;
}
@@ -3123,8 +3129,8 @@ int coroutine_fn
bdrv_co_is_allocated_above(BlockDriverState *top,
intermediate = top;
while (intermediate && intermediate != base) {
int pnum_inter;
- ret = bdrv_co_is_allocated(intermediate, sector_num, nb_sectors,
- &pnum_inter);
+ ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors,
+ &pnum_inter);
if (ret < 0) {
return ret;
} else if (ret) {
diff --git a/block/backup.c b/block/backup.c
index 23c7264..481758d 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -289,14 +289,14 @@ static void coroutine_fn backup_run(void *opaque)
* backing file. */
for (i = 0; i < BACKUP_SECTORS_PER_CLUSTER;) {
- /* bdrv_co_is_allocated() only returns true/false based
+ /* bdrv_is_allocated() only returns true/false based
* on the first set of sectors it comes across that
* are are all in the same state.
* For that reason we must verify each sector in the
* backup cluster length. We end up copying more than
* needed but at some point that is always the case. */
alloced =
- bdrv_co_is_allocated(bs,
+ bdrv_is_allocated(bs,
start * BACKUP_SECTORS_PER_CLUSTER + i,
BACKUP_SECTORS_PER_CLUSTER - i, &n);
i += n;
diff --git a/block/raw_bsd.c b/block/raw_bsd.c
index ab2b0fd..926712e 100644
--- a/block/raw_bsd.c
+++ b/block/raw_bsd.c
@@ -62,7 +62,7 @@ static int coroutine_fn raw_co_is_allocated(BlockDriverState
*bs,
int64_t sector_num, int nb_sectors,
int *pnum)
{
- return bdrv_co_is_allocated(bs->file, sector_num, nb_sectors, pnum);
+ return bdrv_is_allocated(bs->file, sector_num, nb_sectors, pnum);
}
static int coroutine_fn raw_co_write_zeroes(BlockDriverState *bs,
diff --git a/block/stream.c b/block/stream.c
index 9982125..cc131e8 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -119,8 +119,8 @@ wait:
break;
}
- ret = bdrv_co_is_allocated(bs, sector_num,
- STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n);
+ ret = bdrv_is_allocated(bs, sector_num,
+ STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n);
if (ret == 1) {
/* Allocated in the top, no need to copy. */
copy = false;
diff --git a/include/block/block.h b/include/block/block.h
index e6b391c..33f7a9d 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -181,8 +181,6 @@ int coroutine_fn bdrv_co_writev(BlockDriverState *bs,
int64_t sector_num,
*/
int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
int nb_sectors);
-int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, int *pnum);
int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top,
BlockDriverState *base,
int64_t sector_num,
--
1.8.3.1
