Re: [Virtio-fs] [PATCH v4 1/2] virtiofsd: add definition of fuse_buf_writev()

[piaojun <piaojun@huawei.com>]

Hi Dave,

I just found a little mistake of this patch as below. Could you help
squash into this patch?

Fixes: fea3e6e5ec76 ("add definition of fuse_buf_writev()")

Thanks,
Jun

On 2019/8/15 1:07, Dr. David Alan Gilbert wrote:
> * piaojun (piaojun@huawei.com) wrote:
>> Define fuse_buf_writev() which use pwritev and writev to improve io
>> bandwidth.
>>
>> Signed-off-by: Jun Piao <piaojun@huawei.com>
>> Suggested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
>> Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
> 
> Yep, this part looks OK,
> 
> 
> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> 
>> ---
>>  contrib/virtiofsd/buffer.c  | 31 +++++++++++++++++++++++++++++++
>>  contrib/virtiofsd/seccomp.c |  2 ++
>>  2 files changed, 33 insertions(+)
>>
>> diff --git a/contrib/virtiofsd/buffer.c b/contrib/virtiofsd/buffer.c
>> index 655be137..cec762f 100644
>> --- a/contrib/virtiofsd/buffer.c
>> +++ b/contrib/virtiofsd/buffer.c
>> @@ -15,6 +15,7 @@
>>  #include <unistd.h>
>>  #include <errno.h>
>>  #include <assert.h>
>> +#include <stdlib.h>
>>
>>  size_t fuse_buf_size(const struct fuse_bufvec *bufv)
>>  {
>> @@ -71,6 +72,36 @@ static ssize_t fuse_buf_write(const struct fuse_buf *dst, size_t dst_off,
>>  	return copied;
>>  }
>>
>> +static ssize_t fuse_buf_writev(fuse_req_t req,
>> +			     struct fuse_buf *out_buf,
>> +			     struct fuse_bufvec *in_buf)

*req* could be cleaned up as it is unused.

>> +{
>> +	ssize_t res, i;
>> +	size_t iovcnt = in_buf->count;
>> +	struct iovec * iov;
>> +	int fd = out_buf->fd;
>> +
>> +	iov = calloc(iovcnt, sizeof(struct iovec));
>> +	if (!iov)
>> +		return -ENOMEM;
>> +
>> +	for (i = 0; i < iovcnt; i++) {
>> +		iov[i].iov_base = in_buf->buf[i].mem;
>> +		iov[i].iov_len = in_buf->buf[i].size;
>> +	}
>> +
>> +	if (out_buf->flags & FUSE_BUF_FD_SEEK)
>> +		res = pwritev(fd, iov, iovcnt, out_buf->pos);
>> +	else
>> +		res = writev(fd, iov, iovcnt);
>> +
>> +	if (res == -1)
>> +		res = -errno;
>> +
>> +	free(iov);
>> +	return res;
>> +}
>> +
>>  static ssize_t fuse_buf_read(const struct fuse_buf *dst, size_t dst_off,
>>  			     const struct fuse_buf *src, size_t src_off,
>>  			     size_t len)
>> diff --git a/contrib/virtiofsd/seccomp.c b/contrib/virtiofsd/seccomp.c
>> index 5f1c873..4bba30b 100644
>> --- a/contrib/virtiofsd/seccomp.c
>> +++ b/contrib/virtiofsd/seccomp.c
>> @@ -60,6 +60,7 @@ static const int syscall_whitelist[] = {
>>  	SCMP_SYS(ppoll),
>>  	SCMP_SYS(prctl), /* TODO restrict to just PR_SET_NAME? */
>>  	SCMP_SYS(preadv),
>> +	SCMP_SYS(pwritev),
>>  	SCMP_SYS(pwrite64),
>>  	SCMP_SYS(read),
>>  	SCMP_SYS(readlinkat),
>> @@ -78,6 +79,7 @@ static const int syscall_whitelist[] = {
>>  	SCMP_SYS(unlinkat),
>>  	SCMP_SYS(utimensat),
>>  	SCMP_SYS(write),
>> +	SCMP_SYS(writev),
>>  };
>>
>>  /* Syscalls used when --syslog is enabled */
>> -- 
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> .
>