From 02cf01aea5af7a4d1a38045712fe11bffcc206b0 Mon Sep 17 00:00:00 2001
From: Jens Axboe <jens.axboe@oracle.com>
Date: Wed, 20 Feb 2008 10:34:51 +0100
Subject: splice: only return -EAGAIN if there's hope of more data

sys_tee() currently is a bit eager in returning -EAGAIN, it may do so
even if we don't have a chance of anymore data becoming available. So
improve the logic and only return -EAGAIN if we have an attached writer
to the input pipe.

Reported by Johann Felix Soden <johfel@gmx.de> and
Patrick McManus <mcmanus@ducksong.com>.

Tested-by: Johann Felix Soden <johfel@users.sourceforge.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 fs/splice.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

(limited to 'fs')

diff --git a/fs/splice.c b/fs/splice.c
index 9b559ee711a..0670c915cd3 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -1669,6 +1669,13 @@ static int link_pipe(struct pipe_inode_info *ipipe,
 		i++;
 	} while (len);
 
+	/*
+	 * return EAGAIN if we have the potential of some data in the
+	 * future, otherwise just return 0
+	 */
+	if (!ret && ipipe->waiting_writers && (flags & SPLICE_F_NONBLOCK))
+		ret = -EAGAIN;
+
 	inode_double_unlock(ipipe->inode, opipe->inode);
 
 	/*
@@ -1709,11 +1716,8 @@ static long do_tee(struct file *in, struct file *out, size_t len,
 		ret = link_ipipe_prep(ipipe, flags);
 		if (!ret) {
 			ret = link_opipe_prep(opipe, flags);
-			if (!ret) {
+			if (!ret)
 				ret = link_pipe(ipipe, opipe, len, flags);
-				if (!ret && (flags & SPLICE_F_NONBLOCK))
-					ret = -EAGAIN;
-			}
 		}
 	}
 
-- 
cgit v1.2.3


From a0db701a6bf767320e4471bd55e70702d230f6fb Mon Sep 17 00:00:00 2001
From: Adrian Bunk <bunk@kernel.org>
Date: Tue, 4 Mar 2008 11:23:50 +0100
Subject: block/genhd.c: proper externs

This patch adds proper externs for two structs in include/linux/genhd.h

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 fs/proc/proc_misc.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

(limited to 'fs')

diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index 468805d40e2..2d563979cb0 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -32,6 +32,7 @@
 #include <linux/interrupt.h>
 #include <linux/swap.h>
 #include <linux/slab.h>
+#include <linux/genhd.h>
 #include <linux/smp.h>
 #include <linux/signal.h>
 #include <linux/module.h>
@@ -377,7 +378,6 @@ static int stram_read_proc(char *page, char **start, off_t off,
 #endif
 
 #ifdef CONFIG_BLOCK
-extern const struct seq_operations partitions_op;
 static int partitions_open(struct inode *inode, struct file *file)
 {
 	return seq_open(file, &partitions_op);
@@ -389,7 +389,6 @@ static const struct file_operations proc_partitions_operations = {
 	.release	= seq_release,
 };
 
-extern const struct seq_operations diskstats_op;
 static int diskstats_open(struct inode *inode, struct file *file)
 {
 	return seq_open(file, &diskstats_op);
-- 
cgit v1.2.3