[PATCH STABLE 4.4 6/8] pipe: add pipe_buf_get() helper

From: Vlastimil Babka
Date: Fri Nov 08 2019 - 04:38:32 EST


From: Miklos Szeredi <mszeredi@xxxxxxxxxx>

commit 7bf2d1df80822ec056363627e2014990f068f7aa upstream.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
---
fs/fuse/dev.c | 2 +-
fs/splice.c | 4 ++--
include/linux/pipe_fs_i.h | 11 +++++++++++
3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index f5d2d2340b44..36a5df92eb9c 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -2052,7 +2052,7 @@ static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
pipe->nrbufs--;
} else {
- ibuf->ops->get(pipe, ibuf);
+ pipe_buf_get(pipe, ibuf);
*obuf = *ibuf;
obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
obuf->len = rem;
diff --git a/fs/splice.c b/fs/splice.c
index 8398974e1538..fde126369966 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -1876,7 +1876,7 @@ static int splice_pipe_to_pipe(struct pipe_inode_info *ipipe,
* Get a reference to this pipe buffer,
* so we can copy the contents over.
*/
- ibuf->ops->get(ipipe, ibuf);
+ pipe_buf_get(ipipe, ibuf);
*obuf = *ibuf;

/*
@@ -1948,7 +1948,7 @@ static int link_pipe(struct pipe_inode_info *ipipe,
* Get a reference to this pipe buffer,
* so we can copy the contents over.
*/
- ibuf->ops->get(ipipe, ibuf);
+ pipe_buf_get(ipipe, ibuf);

obuf = opipe->bufs + nbuf;
*obuf = *ibuf;
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index 24f5470d3944..10876f3cb3da 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -115,6 +115,17 @@ struct pipe_buf_operations {
void (*get)(struct pipe_inode_info *, struct pipe_buffer *);
};

+/**
+ * pipe_buf_get - get a reference to a pipe_buffer
+ * @pipe: the pipe that the buffer belongs to
+ * @buf: the buffer to get a reference to
+ */
+static inline void pipe_buf_get(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ buf->ops->get(pipe, buf);
+}
+
/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
#define PIPE_SIZE PAGE_SIZE
--
2.23.0