[Intel-gfx] [PATCH 1/9] relay: remove unused buf_mapped and buf_unmapped callbacks

[Jani Nikula]

No relay client uses the buf_mapped or buf_unmapped callbacks. Remove
them. This makes relay's vm_operations_struct close callback a dummy,
remove it as well.

Suggested-by: Christoph Hellwig <hch at infradead.org>
Cc: Christoph Hellwig <hch at infradead.org>
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 include/linux/relay.h | 19 -------------------
 kernel/relay.c        | 34 ----------------------------------
 2 files changed, 53 deletions(-)

diff --git a/include/linux/relay.h b/include/linux/relay.h
index e13a333e7c37..b3c4f49f6951 100644
--- a/include/linux/relay.h
+++ b/include/linux/relay.h
@@ -101,25 +101,6 @@ struct rchan_callbacks
 			     void *prev_subbuf,
 			     size_t prev_padding);
 
-	/*
-	 * buf_mapped - relay buffer mmap notification
-	 * @buf: the channel buffer
-	 * @filp: relay file pointer
-	 *
-	 * Called when a relay file is successfully mmapped
-	 */
-        void (*buf_mapped)(struct rchan_buf *buf,
-			   struct file *filp);
-
-	/*
-	 * buf_unmapped - relay buffer unmap notification
-	 * @buf: the channel buffer
-	 * @filp: relay file pointer
-	 *
-	 * Called when a relay file is successfully unmapped
-	 */
-        void (*buf_unmapped)(struct rchan_buf *buf,
-			     struct file *filp);
 	/*
 	 * create_buf_file - create file to represent a relay channel buffer
 	 * @filename: the name of the file to create
diff --git a/kernel/relay.c b/kernel/relay.c
index b08d936d5fa7..b51343642bf4 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -27,15 +27,6 @@
 static DEFINE_MUTEX(relay_channels_mutex);
 static LIST_HEAD(relay_channels);
 
-/*
- * close() vm_op implementation for relay file mapping.
- */
-static void relay_file_mmap_close(struct vm_area_struct *vma)
-{
-	struct rchan_buf *buf = vma->vm_private_data;
-	buf->chan->cb->buf_unmapped(buf, vma->vm_file);
-}
-
 /*
  * fault() vm_op implementation for relay file mapping.
  */
@@ -62,7 +53,6 @@ static vm_fault_t relay_buf_fault(struct vm_fault *vmf)
  */
 static const struct vm_operations_struct relay_file_mmap_ops = {
 	.fault = relay_buf_fault,
-	.close = relay_file_mmap_close,
 };
 
 /*
@@ -96,7 +86,6 @@ static void relay_free_page_array(struct page **array)
 static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
 {
 	unsigned long length = vma->vm_end - vma->vm_start;
-	struct file *filp = vma->vm_file;
 
 	if (!buf)
 		return -EBADF;
@@ -107,7 +96,6 @@ static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma)
 	vma->vm_ops = &relay_file_mmap_ops;
 	vma->vm_flags |= VM_DONTEXPAND;
 	vma->vm_private_data = buf;
-	buf->chan->cb->buf_mapped(buf, filp);
 
 	return 0;
 }
@@ -283,22 +271,6 @@ static int subbuf_start_default_callback (struct rchan_buf *buf,
 	return 1;
 }
 
-/*
- * buf_mapped() default callback.  Does nothing.
- */
-static void buf_mapped_default_callback(struct rchan_buf *buf,
-					struct file *filp)
-{
-}
-
-/*
- * buf_unmapped() default callback.  Does nothing.
- */
-static void buf_unmapped_default_callback(struct rchan_buf *buf,
-					  struct file *filp)
-{
-}
-
 /*
  * create_buf_file_create() default callback.  Does nothing.
  */
@@ -322,8 +294,6 @@ static int remove_buf_file_default_callback(struct dentry *dentry)
 /* relay channel default callbacks */
 static struct rchan_callbacks default_channel_callbacks = {
 	.subbuf_start = subbuf_start_default_callback,
-	.buf_mapped = buf_mapped_default_callback,
-	.buf_unmapped = buf_unmapped_default_callback,
 	.create_buf_file = create_buf_file_default_callback,
 	.remove_buf_file = remove_buf_file_default_callback,
 };
@@ -509,10 +479,6 @@ static void setup_callbacks(struct rchan *chan,
 
 	if (!cb->subbuf_start)
 		cb->subbuf_start = subbuf_start_default_callback;
-	if (!cb->buf_mapped)
-		cb->buf_mapped = buf_mapped_default_callback;
-	if (!cb->buf_unmapped)
-		cb->buf_unmapped = buf_unmapped_default_callback;
 	if (!cb->create_buf_file)
 		cb->create_buf_file = create_buf_file_default_callback;
 	if (!cb->remove_buf_file)
-- 
2.20.1