diff mbox series

[098/104] virtiofsd: add definition of fuse_buf_writev()

Message ID 20191212163904.159893-99-dgilbert@redhat.com
State New
Headers show
Series virtiofs daemon [all] | expand

Commit Message

Dr. David Alan Gilbert Dec. 12, 2019, 4:38 p.m. UTC 
From: piaojun <piaojun@huawei.com>

Define fuse_buf_writev() which use pwritev and writev to improve io
bandwidth. Especially, the src bufs with 0 size should be skipped as
their mems are not *block_size* aligned which will cause writev failed
in direct io mode.

Signed-off-by: Jun Piao <piaojun@huawei.com>
Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 tools/virtiofsd/buffer.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

Comments

Daniel P. Berrangé Jan. 7, 2020, 12:21 p.m. UTC | #1 
On Thu, Dec 12, 2019 at 04:38:58PM +0000, Dr. David Alan Gilbert (git) wrote:
> From: piaojun <piaojun@huawei.com>
> 
> Define fuse_buf_writev() which use pwritev and writev to improve io
> bandwidth. Especially, the src bufs with 0 size should be skipped as
> their mems are not *block_size* aligned which will cause writev failed
> in direct io mode.
> 
> Signed-off-by: Jun Piao <piaojun@huawei.com>
> Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  tools/virtiofsd/buffer.c | 39 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


Regards,
Daniel
diff mbox series

Patch

diff --git a/tools/virtiofsd/buffer.c b/tools/virtiofsd/buffer.c
index f59d8d72eb..ae420c70c4 100644
--- a/tools/virtiofsd/buffer.c
+++ b/tools/virtiofsd/buffer.c
@@ -13,6 +13,7 @@ 
 #include "fuse_lowlevel.h"
 #include <assert.h>
 #include <errno.h>
+#include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 
@@ -32,6 +33,44 @@  size_t fuse_buf_size(const struct fuse_bufvec *bufv)
     return size;
 }
 
+__attribute__((unused))
+static ssize_t fuse_buf_writev(fuse_req_t req,
+                               struct fuse_buf *out_buf,
+                               struct fuse_bufvec *in_buf)
+{
+    ssize_t res, i, j;
+    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, j = 0; i < iovcnt; i++) {
+        /* Skip the buf with 0 size */
+        if (in_buf->buf[i].size) {
+            iov[j].iov_base = in_buf->buf[i].mem;
+            iov[j].iov_len = in_buf->buf[i].size;
+            j++;
+        }
+    }
+
+    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 size_t min_size(size_t s1, size_t s2)
 {
     return s1 < s2 ? s1 : s2;