From 9eee8bd81421c5e961cbb1a3c3fa1a06fad545e8 Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 22 May 2023 14:50:18 +0100 Subject: splice: kdoc for filemap_splice_read() and copy_splice_read() Provide kerneldoc comments for filemap_splice_read() and copy_splice_read(). Signed-off-by: David Howells cc: Christian Brauner cc: Christoph Hellwig cc: Jens Axboe cc: Steve French cc: Al Viro cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20230522135018.2742245-32-dhowells@redhat.com Signed-off-by: Jens Axboe --- fs/splice.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) (limited to 'fs/splice.c') diff --git a/fs/splice.c b/fs/splice.c index 9be4cb3b9879..2420ead610a7 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -299,8 +299,25 @@ void splice_shrink_spd(struct splice_pipe_desc *spd) kfree(spd->partial); } -/* - * Copy data from a file into pages and then splice those into the output pipe. +/** + * copy_splice_read - Copy data from a file and splice the copy into a pipe + * @in: The file to read from + * @ppos: Pointer to the file position to read from + * @pipe: The pipe to splice into + * @len: The amount to splice + * @flags: The SPLICE_F_* flags + * + * This function allocates a bunch of pages sufficient to hold the requested + * amount of data (but limited by the remaining pipe capacity), passes it to + * the file's ->read_iter() to read into and then splices the used pages into + * the pipe. + * + * Return: On success, the number of bytes read will be returned and *@ppos + * will be updated if appropriate; 0 will be returned if there is no more data + * to be read; -EAGAIN will be returned if the pipe had no space, and some + * other negative error code will be returned on error. A short read may occur + * if the pipe has insufficient space, we reach the end of the data or we hit a + * hole. */ ssize_t copy_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, -- cgit v1.2.3