This is a note to let you know that I've just added the patch titled
fs/pipe: move check to pipe_has_watch_queue()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fs-pipe-move-check-to-pipe_has_watch_queue.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7cd9eb3b5dad6933775395a0edf7a8023fb62989
Author: Max Kellermann <max.kellermann@xxxxxxxxx>
Date: Thu Sep 21 09:57:53 2023 +0200
fs/pipe: move check to pipe_has_watch_queue()
[ Upstream commit b4bd6b4bac8edd61eb8f7b836969d12c0c6af165 ]
This declutters the code by reducing the number of #ifdefs and makes
the watch_queue checks simpler. This has no runtime effect; the
machine code is identical.
Signed-off-by: Max Kellermann <max.kellermann@xxxxxxxxx>
Message-Id: <20230921075755.1378787-2-max.kellermann@xxxxxxxxx>
Reviewed-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
Stable-dep-of: e95aada4cb93 ("pipe: wakeup wr_wait after setting max_usage")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/pipe.c b/fs/pipe.c
index dbb090e1b026..7b3e94baba21 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -435,12 +435,10 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
goto out;
}
-#ifdef CONFIG_WATCH_QUEUE
- if (pipe->watch_queue) {
+ if (pipe_has_watch_queue(pipe)) {
ret = -EXDEV;
goto out;
}
-#endif
/*
* If it wasn't empty we try to merge new data into
@@ -1319,10 +1317,8 @@ static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long arg)
unsigned int nr_slots, size;
long ret = 0;
-#ifdef CONFIG_WATCH_QUEUE
- if (pipe->watch_queue)
+ if (pipe_has_watch_queue(pipe))
return -EBUSY;
-#endif
size = round_pipe_size(arg);
nr_slots = size >> PAGE_SHIFT;
@@ -1375,10 +1371,8 @@ struct pipe_inode_info *get_pipe_info(struct file *file, bool for_splice)
if (file->f_op != &pipefifo_fops || !pipe)
return NULL;
-#ifdef CONFIG_WATCH_QUEUE
- if (for_splice && pipe->watch_queue)
+ if (for_splice && pipe_has_watch_queue(pipe))
return NULL;
-#endif
return pipe;
}
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index ef236dbaa294..7b72d93c2653 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -124,6 +124,22 @@ struct pipe_buf_operations {
bool (*get)(struct pipe_inode_info *, struct pipe_buffer *);
};
+/**
+ * pipe_has_watch_queue - Check whether the pipe is a watch_queue,
+ * i.e. it was created with O_NOTIFICATION_PIPE
+ * @pipe: The pipe to check
+ *
+ * Return: true if pipe is a watch queue, false otherwise.
+ */
+static inline bool pipe_has_watch_queue(const struct pipe_inode_info *pipe)
+{
+#ifdef CONFIG_WATCH_QUEUE
+ return pipe->watch_queue != NULL;
+#else
+ return false;
+#endif
+}
+
/**
* pipe_empty - Return true if the pipe is empty
* @head: The pipe ring head pointer
