fs/pipe: Use pipe_buf() helper to retrieve pipe buffer

Use pipe_buf() helper to retrieve the pipe buffer throughout the file
replacing the open-coded the logic.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20250307052919.34542-4-kprateek.nayak@amd.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/pipe.c b/fs/pipe.c
index 88e81f84e3eaf887989f1a791ce83987d24c75f8..4d6ca0f892b1cc2683a925c7831140f061eb392c 100644 (file)
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -274,7 +274,6 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to)
                /* Read ->head with a barrier vs post_one_notification() */
                unsigned int head = smp_load_acquire(&pipe->head);
                unsigned int tail = pipe->tail;
-               unsigned int mask = pipe->ring_size - 1;
 
 #ifdef CONFIG_WATCH_QUEUE
                if (pipe->note_loss) {
@@ -301,7 +300,7 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to)
 #endif
 
                if (!pipe_empty(head, tail)) {
-                       struct pipe_buffer *buf = &pipe->bufs[tail & mask];
+                       struct pipe_buffer *buf = pipe_buf(pipe, tail);
                        size_t chars = buf->len;
                        size_t written;
                        int error;
@@ -471,8 +470,7 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
        was_empty = pipe_empty(head, pipe->tail);
        chars = total_len & (PAGE_SIZE-1);
        if (chars && !was_empty) {
-               unsigned int mask = pipe->ring_size - 1;
-               struct pipe_buffer *buf = &pipe->bufs[(head - 1) & mask];
+               struct pipe_buffer *buf = pipe_buf(pipe, head - 1);
                int offset = buf->offset + buf->len;
 
                if ((buf->flags & PIPE_BUF_FLAG_CAN_MERGE) &&
@@ -503,7 +501,6 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
 
                head = pipe->head;
                if (!pipe_full(head, pipe->tail, pipe->max_usage)) {
-                       unsigned int mask = pipe->ring_size - 1;
                        struct pipe_buffer *buf;
                        struct page *page = pipe->tmp_page;
                        int copied;
@@ -525,7 +522,7 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
                        pipe->head = head + 1;
 
                        /* Insert it into the buffer array */
-                       buf = &pipe->bufs[head & mask];
+                       buf = pipe_buf(pipe, head);
                        buf->page = page;
                        buf->ops = &anon_pipe_buf_ops;
                        buf->offset = 0;