[RFC,2/4] fs/splice: add helper of splice_dismiss_pipe()
Commit Message
Add helper of splice_dismiss_pipe(), so cleanup iter_file_splice_write
a bit.
And this helper will be reused in the following patch for supporting
to consume pipe by ->splice_read().
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
fs/splice.c | 47 ++++++++++++++++++++++++++++++-----------------
1 file changed, 30 insertions(+), 17 deletions(-)
@@ -282,6 +282,34 @@ void splice_shrink_spd(struct splice_pipe_desc *spd)
kfree(spd->partial);
}
+/* return if wakeup is needed */
+static bool splice_dismiss_pipe(struct pipe_inode_info *pipe, ssize_t bytes)
+{
+ unsigned int mask = pipe->ring_size - 1;
+ unsigned int tail = pipe->tail;
+ bool need_wakeup = false;
+
+ while (bytes) {
+ struct pipe_buffer *buf = &pipe->bufs[tail & mask];
+
+ if (bytes >= buf->len) {
+ bytes -= buf->len;
+ buf->len = 0;
+ pipe_buf_release(pipe, buf);
+ tail++;
+ pipe->tail = tail;
+ if (pipe->files)
+ need_wakeup = true;
+ } else {
+ buf->offset += bytes;
+ buf->len -= bytes;
+ bytes = 0;
+ }
+ }
+
+ return need_wakeup;
+}
+
/**
* generic_file_splice_read - splice data from file to a pipe
* @in: file to splice from
@@ -692,23 +720,8 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
*ppos = sd.pos;
/* dismiss the fully eaten buffers, adjust the partial one */
- tail = pipe->tail;
- while (ret) {
- struct pipe_buffer *buf = &pipe->bufs[tail & mask];
- if (ret >= buf->len) {
- ret -= buf->len;
- buf->len = 0;
- pipe_buf_release(pipe, buf);
- tail++;
- pipe->tail = tail;
- if (pipe->files)
- sd.need_wakeup = true;
- } else {
- buf->offset += ret;
- buf->len -= ret;
- ret = 0;
- }
- }
+ if (splice_dismiss_pipe(pipe, ret))
+ sd.need_wakeup = true;
}
done:
kfree(array);