diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2011-10-20 13:16:22 +0200 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2011-10-21 17:34:14 +0200 |
| commit | 2914caa088e3fbbdbfd73106af0cae49af1d472e (patch) | |
| tree | 07d3de39e3839400dd903e53c3a86e5224c58def /block/nbd.c | |
| parent | 848c66e8f5b631961580f7f010a5831430dc84c2 (diff) | |
block: take lock around bdrv_read implementations
This does the first part of the conversion to coroutines, by
wrapping bdrv_read implementations to take the mutex.
Drivers that implement bdrv_read rather than bdrv_co_readv can
then benefit from asynchronous operation (at least if the underlying
protocol supports it, which is not the case for raw-win32), even
though they still operate with a bounce buffer.
raw-win32 does not need the lock, because it cannot yield.
nbd also doesn't probably, but better be safe.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block/nbd.c')
| -rw-r--r-- | block/nbd.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/block/nbd.c b/block/nbd.c index 14ab2259c2..6b22ae1d15 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -240,6 +240,17 @@ static int nbd_write(BlockDriverState *bs, int64_t sector_num, return 0; } +static coroutine_fn int nbd_co_read(BlockDriverState *bs, int64_t sector_num, + uint8_t *buf, int nb_sectors) +{ + int ret; + BDRVNBDState *s = bs->opaque; + qemu_co_mutex_lock(&s->lock); + ret = nbd_read(bs, sector_num, buf, nb_sectors); + qemu_co_mutex_unlock(&s->lock); + return ret; +} + static void nbd_close(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; @@ -260,7 +271,7 @@ static BlockDriver bdrv_nbd = { .format_name = "nbd", .instance_size = sizeof(BDRVNBDState), .bdrv_file_open = nbd_open, - .bdrv_read = nbd_read, + .bdrv_read = nbd_co_read, .bdrv_write = nbd_write, .bdrv_close = nbd_close, .bdrv_getlength = nbd_getlength, |