[PATCH 07/11] pipe: remove generic_pipe_buf_confirm()

[Miklos Szeredi]

Now all instances of .confirm are set to generic_pipe_buf_confirm().  The
method and the helper can be removed.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
---
 fs/pipe.c                 | 18 ------------------
 fs/splice.c               |  4 ----
 include/linux/pipe_fs_i.h | 18 +-----------------
 kernel/relay.c            |  1 -
 kernel/trace/trace.c      |  2 --
 5 files changed, 1 insertion(+), 42 deletions(-)

diff --git a/fs/pipe.c b/fs/pipe.c
index 4fc422f0dea8..47b41568b3fc 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -200,22 +200,6 @@ void generic_pipe_buf_get(struct pipe_inode_info *pipe, struct pipe_buffer *buf)
 EXPORT_SYMBOL(generic_pipe_buf_get);
 
 /**
- * generic_pipe_buf_confirm - verify contents of the pipe buffer
- * @info:	the pipe that the buffer belongs to
- * @buf:	the buffer to confirm
- *
- * Description:
- *	This function does nothing, because the generic pipe code uses
- *	pages that are always good when inserted into the pipe.
- */
-int generic_pipe_buf_confirm(struct pipe_inode_info *info,
-			     struct pipe_buffer *buf)
-{
-	return 0;
-}
-EXPORT_SYMBOL(generic_pipe_buf_confirm);
-
-/**
  * generic_pipe_buf_release - put a reference to a &struct pipe_buffer
  * @pipe:	the pipe that the buffer belongs to
  * @buf:	the buffer to put a reference to
@@ -232,7 +216,6 @@ EXPORT_SYMBOL(generic_pipe_buf_release);
 
 static const struct pipe_buf_operations anon_pipe_buf_ops = {
 	.can_merge = 1,
-	.confirm = generic_pipe_buf_confirm,
 	.release = anon_pipe_buf_release,
 	.steal = anon_pipe_buf_steal,
 	.get = generic_pipe_buf_get,
@@ -240,7 +223,6 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = {
 
 static const struct pipe_buf_operations packet_pipe_buf_ops = {
 	.can_merge = 0,
-	.confirm = generic_pipe_buf_confirm,
 	.release = anon_pipe_buf_release,
 	.steal = anon_pipe_buf_steal,
 	.get = generic_pipe_buf_get,
diff --git a/fs/splice.c b/fs/splice.c
index 0ecbe3011796..dc4648ba6e8d 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -95,7 +95,6 @@ static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe,
 
 const struct pipe_buf_operations page_cache_pipe_buf_ops = {
 	.can_merge = 0,
-	.confirm = generic_pipe_buf_confirm,
 	.release = page_cache_pipe_buf_release,
 	.steal = page_cache_pipe_buf_steal,
 	.get = generic_pipe_buf_get,
@@ -113,7 +112,6 @@ static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe,
 
 static const struct pipe_buf_operations user_page_pipe_buf_ops = {
 	.can_merge = 0,
-	.confirm = generic_pipe_buf_confirm,
 	.release = page_cache_pipe_buf_release,
 	.steal = user_page_pipe_buf_steal,
 	.get = generic_pipe_buf_get,
@@ -507,7 +505,6 @@ EXPORT_SYMBOL(generic_file_splice_read);
 
 static const struct pipe_buf_operations default_pipe_buf_ops = {
 	.can_merge = 0,
-	.confirm = generic_pipe_buf_confirm,
 	.release = generic_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
 	.get = generic_pipe_buf_get,
@@ -522,7 +519,6 @@ static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe,
 /* Pipe buffer operations for a socket and similar. */
 const struct pipe_buf_operations nosteal_pipe_buf_ops = {
 	.can_merge = 0,
-	.confirm = generic_pipe_buf_confirm,
 	.release = generic_pipe_buf_release,
 	.steal = generic_pipe_buf_nosteal,
 	.get = generic_pipe_buf_get,
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index e7497c9dde7f..ae9d87ea95cb 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -62,12 +62,6 @@ struct pipe_inode_info {
 };
 
 /*
- * Note on the nesting of these functions:
- *
- * ->confirm()
- *	->steal()
- *
- * That is, ->steal() must be called on a confirmed buffer.
  * See below for the meaning of each operation. Also see kerneldoc
  * in fs/pipe.c for the pipe and generic variants of these hooks.
  */
@@ -80,15 +74,6 @@ struct pipe_buf_operations {
 	int can_merge;
 
 	/*
-	 * ->confirm() verifies that the data in the pipe buffer is there
-	 * and that the contents are good. If the pages in the pipe belong
-	 * to a file system, we may need to wait for IO completion in this
-	 * hook. Returns 0 for good, or a negative error value in case of
-	 * error.
-	 */
-	int (*confirm)(struct pipe_inode_info *, struct pipe_buffer *);
-
-	/*
 	 * When the contents of this pipe buffer has been completely
 	 * consumed by a reader, ->release() is called.
 	 */
@@ -143,7 +128,7 @@ static inline void pipe_buf_release(struct pipe_inode_info *pipe,
 static inline int pipe_buf_confirm(struct pipe_inode_info *pipe,
 				   struct pipe_buffer *buf)
 {
-	return buf->ops->confirm(pipe, buf);
+	return 0;
 }
 
 /**
@@ -179,7 +164,6 @@ void free_pipe_info(struct pipe_inode_info *);
 
 /* Generic pipe buffer ops functions */
 void generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *);
-int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *);
 int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *);
 void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *);
 
diff --git a/kernel/relay.c b/kernel/relay.c
index d797502140b9..da954ce520b2 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -1223,7 +1223,6 @@ static void relay_pipe_buf_release(struct pipe_inode_info *pipe,
 
 static const struct pipe_buf_operations relay_pipe_buf_ops = {
 	.can_merge = 0,
-	.confirm = generic_pipe_buf_confirm,
 	.release = relay_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
 	.get = generic_pipe_buf_get,
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index dade4c9559cc..bdf891c78708 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5219,7 +5219,6 @@ static void tracing_spd_release_pipe(struct splice_pipe_desc *spd,
 
 static const struct pipe_buf_operations tracing_pipe_buf_ops = {
 	.can_merge		= 0,
-	.confirm		= generic_pipe_buf_confirm,
 	.release		= generic_pipe_buf_release,
 	.steal			= generic_pipe_buf_steal,
 	.get			= generic_pipe_buf_get,
@@ -6114,7 +6113,6 @@ static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
 /* Pipe buffer operations for a buffer. */
 static const struct pipe_buf_operations buffer_pipe_buf_ops = {
 	.can_merge		= 0,
-	.confirm		= generic_pipe_buf_confirm,
 	.release		= buffer_pipe_buf_release,
 	.steal			= generic_pipe_buf_steal,
 	.get			= buffer_pipe_buf_get,
-- 
2.5.5