Commit 534f2aaa authored by Jens Axboe's avatar Jens Axboe
Browse files

sys_sendfile: switch to using ->splice_read, if available 



This patch makes sendfile prefer to use ->splice_read(), if it's
available in the file_operations structure.

Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent 6a14b90b

fs/read_write.c

+20 −4
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <linux/module.h>

#include <linux/syscalls.h>

#include <linux/pagemap.h>

#include <linux/pipe_fs_i.h>

#include "read_write.h"



#include <asm/uaccess.h>
@@ -25,7 +26,7 @@ const struct file_operations generic_ro_fops = { 
	.read		= do_sync_read,

	.aio_read	= generic_file_aio_read,

	.mmap		= generic_file_readonly_mmap,

	.sendfile	= generic_file_sendfile,

	.splice_read	= generic_file_splice_read,

};



EXPORT_SYMBOL(generic_ro_fops);
@@ -708,7 +709,7 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, 
	struct inode * in_inode, * out_inode;

	loff_t pos;

	ssize_t retval;

	int fput_needed_in, fput_needed_out;

	int fput_needed_in, fput_needed_out, fl;



	/*

	 * Get input file, and verify that it is ok..
@@ -723,7 +724,8 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, 
	in_inode = in_file->f_path.dentry->d_inode;

	if (!in_inode)

		goto fput_in;

	if (!in_file->f_op || !in_file->f_op->sendfile)

	if (!in_file->f_op || (!in_file->f_op->sendfile &&

	    !in_file->f_op->splice_read))

		goto fput_in;

	retval = -ESPIPE;

	if (!ppos)
@@ -776,6 +778,20 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, 
		count = max - pos;

	}



	if (in_file->f_op->splice_read) {

		fl = 0;

#if 0

		/*

		 * We need to debate whether we can enable this or not. The

		 * man page documents EAGAIN return for the output at least,

		 * and the application is arguably buggy if it doesn't expect

		 * EAGAIN on a non-blocking file descriptor.

		 */

		if (in_file->f_flags & O_NONBLOCK)

			fl = SPLICE_F_NONBLOCK;

#endif

		retval = do_splice_direct(in_file, ppos, out_file, count, fl);

	} else

		retval = in_file->f_op->sendfile(in_file, ppos, count, file_send_actor, out_file);



	if (retval > 0) {