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Date: Sun, 12 Dec 2010 22:23:50 +0100 (CET)
From: Michał Mirosław <mirq-linux@...e.qmqm.pl>
To: Alexander Viro <viro@...iv.linux.org.uk>,
linux-fsdevel@...r.kernel.org
Cc: linux-kernel@...r.kernel.org,
"J. Bruce Fields" <bfields@...ldses.org>,
Neil Brown <neilb@...e.de>, Jens Axboe <jaxboe@...ionio.com>
Subject: [PATCH] fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
This patch pulls calls to buf->ops->confirm() from all actors passed
(also indirectly) to splice_from_pipe_feed().
Is avoiding the call to buf->ops->confirm() while splice()ing to
/dev/null is an intentional optimization? No other user does that
and this will remove this special case.
Against current linux.git 6313e3c21743cc88bb5bd8aa72948ee1e83937b6.
Signed-off-by: Michał Mirosław <mirq-linux@...e.qmqm.pl>
---
drivers/block/loop.c | 4 ----
fs/nfsd/vfs.c | 4 ----
fs/splice.c | 43 ++++++++++++++-----------------------------
3 files changed, 14 insertions(+), 37 deletions(-)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 7ea0bea..c87b084 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -397,10 +397,6 @@ lo_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
sector_t IV;
int size, ret;
- ret = buf->ops->confirm(pipe, buf);
- if (unlikely(ret))
- return ret;
-
IV = ((sector_t) page->index << (PAGE_CACHE_SHIFT - 9)) +
(buf->offset >> 9);
size = sd->len;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 184938f..c6e0866 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -847,10 +847,6 @@ nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
size_t size;
int ret;
- ret = buf->ops->confirm(pipe, buf);
- if (unlikely(ret))
- return ret;
-
size = sd->len;
if (rqstp->rq_res.page_len == 0) {
diff --git a/fs/splice.c b/fs/splice.c
index ce2f025..50a5d978 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -682,19 +682,14 @@ static int pipe_to_sendpage(struct pipe_inode_info *pipe,
{
struct file *file = sd->u.file;
loff_t pos = sd->pos;
- int ret, more;
-
- ret = buf->ops->confirm(pipe, buf);
- if (!ret) {
- more = (sd->flags & SPLICE_F_MORE) || sd->len < sd->total_len;
- if (file->f_op && file->f_op->sendpage)
- ret = file->f_op->sendpage(file, buf->page, buf->offset,
- sd->len, &pos, more);
- else
- ret = -EINVAL;
- }
+ int more;
- return ret;
+ if (!likely(file->f_op && file->f_op->sendpage))
+ return -EINVAL;
+
+ more = (sd->flags & SPLICE_F_MORE) || sd->len < sd->total_len;
+ return file->f_op->sendpage(file, buf->page, buf->offset,
+ sd->len, &pos, more);
}
/*
@@ -727,13 +722,6 @@ int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
void *fsdata;
int ret;
- /*
- * make sure the data in this buffer is uptodate
- */
- ret = buf->ops->confirm(pipe, buf);
- if (unlikely(ret))
- return ret;
-
offset = sd->pos & ~PAGE_CACHE_MASK;
this_len = sd->len;
@@ -805,12 +793,17 @@ int splice_from_pipe_feed(struct pipe_inode_info *pipe, struct splice_desc *sd,
if (sd->len > sd->total_len)
sd->len = sd->total_len;
- ret = actor(pipe, buf, sd);
- if (ret <= 0) {
+ ret = buf->ops->confirm(pipe, buf);
+ if (unlikely(ret)) {
if (ret == -ENODATA)
ret = 0;
return ret;
}
+
+ ret = actor(pipe, buf, sd);
+ if (ret <= 0)
+ return ret;
+
buf->offset += ret;
buf->len -= ret;
@@ -1044,10 +1037,6 @@ static int write_pipe_buf(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
int ret;
void *data;
- ret = buf->ops->confirm(pipe, buf);
- if (ret)
- return ret;
-
data = buf->ops->map(pipe, buf, 0);
ret = kernel_write(sd->u.file, data + buf->offset, sd->len, sd->pos);
buf->ops->unmap(pipe, buf, data);
@@ -1495,10 +1484,6 @@ static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
char *src;
int ret;
- ret = buf->ops->confirm(pipe, buf);
- if (unlikely(ret))
- return ret;
-
/*
* See if we can use the atomic maps, by prefaulting in the
* pages and doing an atomic copy
--
1.7.2.3
--
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