1 files changed, 40 insertions, 26 deletions

diff --git a/drivers/staging/comedi/comedi_buf.c b/drivers/staging/comedi/comedi_buf.c
index 257595016161..df4a9c4bca35 100644
--- a/drivers/staging/comedi/comedi_buf.c
+++ b/drivers/staging/comedi/comedi_buf.c
@@ -183,9 +183,9 @@ comedi_buf_map_from_subdev_get(struct comedi_subdevice *s)
 	return bm;
 }
 
-bool comedi_buf_is_mmapped(struct comedi_async *async)
+bool comedi_buf_is_mmapped(struct comedi_subdevice *s)
 {
-	struct comedi_buf_map *bm = async->buf_map;
+	struct comedi_buf_map *bm = s->async->buf_map;
 
 	return bm && (atomic_read(&bm->refcount.refcount) > 1);
 }
@@ -222,8 +222,10 @@ int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s,
 	return 0;
 }
 
-void comedi_buf_reset(struct comedi_async *async)
+void comedi_buf_reset(struct comedi_subdevice *s)
 {
+	struct comedi_async *async = s->async;
+
 	async->buf_write_alloc_count = 0;
 	async->buf_write_count = 0;
 	async->buf_read_alloc_count = 0;
@@ -241,18 +243,20 @@ void comedi_buf_reset(struct comedi_async *async)
 	async->events = 0;
 }
 
-static unsigned int comedi_buf_write_n_available(struct comedi_async *async)
+static unsigned int comedi_buf_write_n_available(struct comedi_subdevice *s)
 {
+	struct comedi_async *async = s->async;
 	unsigned int free_end = async->buf_read_count + async->prealloc_bufsz;
 
 	return free_end - async->buf_write_alloc_count;
 }
 
-static unsigned int __comedi_buf_write_alloc(struct comedi_async *async,
+static unsigned int __comedi_buf_write_alloc(struct comedi_subdevice *s,
 					     unsigned int nbytes,
 					     int strict)
 {
-	unsigned int available = comedi_buf_write_n_available(async);
+	struct comedi_async *async = s->async;
+	unsigned int available = comedi_buf_write_n_available(s);
 
 	if (nbytes > available)
 		nbytes = strict ? 0 : available;
@@ -269,10 +273,10 @@ static unsigned int __comedi_buf_write_alloc(struct comedi_async *async,
 }
 
 /* allocates chunk for the writer from free buffer space */
-unsigned int comedi_buf_write_alloc(struct comedi_async *async,
+unsigned int comedi_buf_write_alloc(struct comedi_subdevice *s,
 				    unsigned int nbytes)
 {
-	return __comedi_buf_write_alloc(async, nbytes, 0);
+	return __comedi_buf_write_alloc(s, nbytes, 0);
 }
 EXPORT_SYMBOL_GPL(comedi_buf_write_alloc);
 
@@ -280,10 +284,10 @@ EXPORT_SYMBOL_GPL(comedi_buf_write_alloc);
  * munging is applied to data by core as it passes between user
  * and kernel space
  */
-static unsigned int comedi_buf_munge(struct comedi_async *async,
+static unsigned int comedi_buf_munge(struct comedi_subdevice *s,
 				     unsigned int num_bytes)
 {
-	struct comedi_subdevice *s = async->subdevice;
+	struct comedi_async *async = s->async;
 	unsigned int count = 0;
 	const unsigned num_sample_bytes = bytes_per_sample(s);
 
@@ -323,23 +327,26 @@ static unsigned int comedi_buf_munge(struct comedi_async *async,
 	return count;
 }
 
-unsigned int comedi_buf_write_n_allocated(struct comedi_async *async)
+unsigned int comedi_buf_write_n_allocated(struct comedi_subdevice *s)
 {
+	struct comedi_async *async = s->async;
+
 	return async->buf_write_alloc_count - async->buf_write_count;
 }
 
 /* transfers a chunk from writer to filled buffer space */
-unsigned int comedi_buf_write_free(struct comedi_async *async,
+unsigned int comedi_buf_write_free(struct comedi_subdevice *s,
 				   unsigned int nbytes)
 {
-	unsigned int allocated = comedi_buf_write_n_allocated(async);
+	struct comedi_async *async = s->async;
+	unsigned int allocated = comedi_buf_write_n_allocated(s);
 
 	if (nbytes > allocated)
 		nbytes = allocated;
 
 	async->buf_write_count += nbytes;
 	async->buf_write_ptr += nbytes;
-	comedi_buf_munge(async, async->buf_write_count - async->munge_count);
+	comedi_buf_munge(s, async->buf_write_count - async->munge_count);
 	if (async->buf_write_ptr >= async->prealloc_bufsz)
 		async->buf_write_ptr %= async->prealloc_bufsz;
 
@@ -347,8 +354,9 @@ unsigned int comedi_buf_write_free(struct comedi_async *async,
 }
 EXPORT_SYMBOL_GPL(comedi_buf_write_free);
 
-unsigned int comedi_buf_read_n_available(struct comedi_async *async)
+unsigned int comedi_buf_read_n_available(struct comedi_subdevice *s)
 {
+	struct comedi_async *async = s->async;
 	unsigned num_bytes;
 
 	if (!async)
@@ -367,9 +375,10 @@ unsigned int comedi_buf_read_n_available(struct comedi_async *async)
 EXPORT_SYMBOL_GPL(comedi_buf_read_n_available);
 
 /* allocates a chunk for the reader from filled (and munged) buffer space */
-unsigned int comedi_buf_read_alloc(struct comedi_async *async,
+unsigned int comedi_buf_read_alloc(struct comedi_subdevice *s,
 				   unsigned int nbytes)
 {
+	struct comedi_async *async = s->async;
 	unsigned int available;
 
 	available = async->munge_count - async->buf_read_alloc_count;
@@ -394,9 +403,10 @@ static unsigned int comedi_buf_read_n_allocated(struct comedi_async *async)
 }
 
 /* transfers control of a chunk from reader to free buffer space */
-unsigned int comedi_buf_read_free(struct comedi_async *async,
+unsigned int comedi_buf_read_free(struct comedi_subdevice *s,
 				  unsigned int nbytes)
 {
+	struct comedi_async *async = s->async;
 	unsigned int allocated;
 
 	/*
@@ -416,36 +426,39 @@ unsigned int comedi_buf_read_free(struct comedi_async *async,
 }
 EXPORT_SYMBOL_GPL(comedi_buf_read_free);
 
-int comedi_buf_put(struct comedi_async *async, unsigned short x)
+int comedi_buf_put(struct comedi_subdevice *s, unsigned short x)
 {
-	unsigned int n = __comedi_buf_write_alloc(async, sizeof(short), 1);
+	struct comedi_async *async = s->async;
+	unsigned int n = __comedi_buf_write_alloc(s, sizeof(short), 1);
 
 	if (n < sizeof(short)) {
 		async->events |= COMEDI_CB_ERROR;
 		return 0;
 	}
 	*(unsigned short *)(async->prealloc_buf + async->buf_write_ptr) = x;
-	comedi_buf_write_free(async, sizeof(short));
+	comedi_buf_write_free(s, sizeof(short));
 	return 1;
 }
 EXPORT_SYMBOL_GPL(comedi_buf_put);
 
-int comedi_buf_get(struct comedi_async *async, unsigned short *x)
+int comedi_buf_get(struct comedi_subdevice *s, unsigned short *x)
 {
-	unsigned int n = comedi_buf_read_n_available(async);
+	struct comedi_async *async = s->async;
+	unsigned int n = comedi_buf_read_n_available(s);
 
 	if (n < sizeof(short))
 		return 0;
-	comedi_buf_read_alloc(async, sizeof(short));
+	comedi_buf_read_alloc(s, sizeof(short));
 	*x = *(unsigned short *)(async->prealloc_buf + async->buf_read_ptr);
-	comedi_buf_read_free(async, sizeof(short));
+	comedi_buf_read_free(s, sizeof(short));
 	return 1;
 }
 EXPORT_SYMBOL_GPL(comedi_buf_get);
 
-void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset,
+void comedi_buf_memcpy_to(struct comedi_subdevice *s, unsigned int offset,
 			  const void *data, unsigned int num_bytes)
 {
+	struct comedi_async *async = s->async;
 	unsigned int write_ptr = async->buf_write_ptr + offset;
 
 	if (write_ptr >= async->prealloc_bufsz)
@@ -469,10 +482,11 @@ void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset,
 }
 EXPORT_SYMBOL_GPL(comedi_buf_memcpy_to);
 
-void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset,
+void comedi_buf_memcpy_from(struct comedi_subdevice *s, unsigned int offset,
 			    void *dest, unsigned int nbytes)
 {
 	void *src;
+	struct comedi_async *async = s->async;
 	unsigned int read_ptr = async->buf_read_ptr + offset;
 
 	if (read_ptr >= async->prealloc_bufsz)