Re: [Qemu-devel] [PATCH] block/nfs: Implement .bdrv_co_preadv/pwritev interfaces

[Jeff Cody <jcody@redhat.com>]

On Mon, May 30, 2016 at 01:47:44PM +0200, Peter Lieven wrote:
> the libnfs read and write functions already take byte arguments
> so thats an easy change.
> 
> Signed-off-by: Peter Lieven <pl@kamp.de>
> ---
>  block/nfs.c | 40 +++++++++++++++++++---------------------
>  1 file changed, 19 insertions(+), 21 deletions(-)
> 
> diff --git a/block/nfs.c b/block/nfs.c
> index 9f51cc3..386f846 100644
> --- a/block/nfs.c
> +++ b/block/nfs.c
> @@ -133,20 +133,19 @@ nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
>      }
>  }
>  
> -static int coroutine_fn nfs_co_readv(BlockDriverState *bs,
> -                                     int64_t sector_num, int nb_sectors,
> -                                     QEMUIOVector *iov)
> +static int coroutine_fn
> +nfs_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
> +              QEMUIOVector *qiov, int flags)
>  {
>      NFSClient *client = bs->opaque;
>      NFSRPC task;
>  
>      nfs_co_init_task(client, &task);
> -    task.iov = iov;
> +    task.iov = qiov;
>  
>      if (nfs_pread_async(client->context, client->fh,
> -                        sector_num * BDRV_SECTOR_SIZE,
> -                        nb_sectors * BDRV_SECTOR_SIZE,
> -                        nfs_co_generic_cb, &task) != 0) {
> +                        offset, bytes, nfs_co_generic_cb,
> +                        &task) != 0) {
>          return -ENOMEM;
>      }
>  
> @@ -160,16 +159,16 @@ static int coroutine_fn nfs_co_readv(BlockDriverState *bs,
>      }
>  
>      /* zero pad short reads */
> -    if (task.ret < iov->size) {
> -        qemu_iovec_memset(iov, task.ret, 0, iov->size - task.ret);
> +    if (task.ret < qiov->size) {
> +        qemu_iovec_memset(qiov, task.ret, 0, qiov->size - task.ret);
>      }
>  
>      return 0;
>  }
>  
> -static int coroutine_fn nfs_co_writev(BlockDriverState *bs,
> -                                        int64_t sector_num, int nb_sectors,
> -                                        QEMUIOVector *iov)
> +static int coroutine_fn
> +nfs_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
> +               QEMUIOVector *qiov, int flags)
>  {
>      NFSClient *client = bs->opaque;
>      NFSRPC task;
> @@ -177,17 +176,16 @@ static int coroutine_fn nfs_co_writev(BlockDriverState *bs,
>  
>      nfs_co_init_task(client, &task);
>  
> -    buf = g_try_malloc(nb_sectors * BDRV_SECTOR_SIZE);
> -    if (nb_sectors && buf == NULL) {
> +    buf = g_try_malloc(bytes);
> +    if (bytes && buf == NULL) {
>          return -ENOMEM;
>      }
>  
> -    qemu_iovec_to_buf(iov, 0, buf, nb_sectors * BDRV_SECTOR_SIZE);
> +    qemu_iovec_to_buf(qiov, 0, buf, bytes);
>  
>      if (nfs_pwrite_async(client->context, client->fh,
> -                         sector_num * BDRV_SECTOR_SIZE,
> -                         nb_sectors * BDRV_SECTOR_SIZE,
> -                         buf, nfs_co_generic_cb, &task) != 0) {
> +                         offset, bytes, buf,
> +                         nfs_co_generic_cb, &task) != 0) {
>          g_free(buf);
>          return -ENOMEM;
>      }
> @@ -199,7 +197,7 @@ static int coroutine_fn nfs_co_writev(BlockDriverState *bs,
>  
>      g_free(buf);
>  
> -    if (task.ret != nb_sectors * BDRV_SECTOR_SIZE) {
> +    if (task.ret != bytes) {
>          return task.ret < 0 ? task.ret : -EIO;
>      }
>  
> @@ -547,8 +545,8 @@ static BlockDriver bdrv_nfs = {
>      .bdrv_create                    = nfs_file_create,
>      .bdrv_reopen_prepare            = nfs_reopen_prepare,
>  
> -    .bdrv_co_readv                  = nfs_co_readv,
> -    .bdrv_co_writev                 = nfs_co_writev,
> +    .bdrv_co_preadv                 = nfs_co_preadv,
> +    .bdrv_co_pwritev                = nfs_co_pwritev,
>      .bdrv_co_flush_to_disk          = nfs_co_flush,
>  
>      .bdrv_detach_aio_context        = nfs_detach_aio_context,
> -- 
> 1.9.1
>

Reviewed-by: Jeff Cody <jcody@redhat.com>