dma-buf-map: Rename to iosys-map

Rename struct dma_buf_map to struct iosys_map and corresponding APIs.
Over time dma-buf-map grew up to more functionality than the one used by
dma-buf: in fact it's just a shim layer to abstract system memory, that
can be accessed via regular load and store, from IO memory that needs to
be acessed via arch helpers.

The idea is to extend this API so it can fulfill other needs, internal
to a single driver. Example: in the i915 driver it's desired to share
the implementation for integrated graphics, which uses mostly system
memory, with discrete graphics, which may need to access IO memory.

The conversion was mostly done with the following semantic patch:

	@r1@
	@@
	- struct dma_buf_map
	+ struct iosys_map

	@r2@
	@@
	(
	- DMA_BUF_MAP_INIT_VADDR
	+ IOSYS_MAP_INIT_VADDR
	|
	- dma_buf_map_set_vaddr
	+ iosys_map_set_vaddr
	|
	- dma_buf_map_set_vaddr_iomem
	+ iosys_map_set_vaddr_iomem
	|
	- dma_buf_map_is_equal
	+ iosys_map_is_equal
	|
	- dma_buf_map_is_null
	+ iosys_map_is_null
	|
	- dma_buf_map_is_set
	+ iosys_map_is_set
	|
	- dma_buf_map_clear
	+ iosys_map_clear
	|
	- dma_buf_map_memcpy_to
	+ iosys_map_memcpy_to
	|
	- dma_buf_map_incr
	+ iosys_map_incr
	)

	@@
	@@
	- #include <linux/dma-buf-map.h>
	+ #include <linux/iosys-map.h>

Then some files had their includes adjusted and some comments were
update to remove mentions to dma-buf-map.

Since this is not specific to dma-buf anymore, move the documentation to
the "Bus-Independent Device Accesses" section.

v2:
  - Squash patches

v3:
  - Fix wrong removal of dma-buf.h from MAINTAINERS
  - Move documentation from dma-buf.rst to device-io.rst

v4:
  - Change documentation title and level

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com

3 files changed, 21 insertions, 21 deletions

diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 602b12d7470d..df23239b04fc 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -1047,8 +1047,8 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_move_notify, DMA_BUF);
  *
  *   Interfaces::
  *
- *      void \*dma_buf_vmap(struct dma_buf \*dmabuf, struct dma_buf_map \*map)
- *      void dma_buf_vunmap(struct dma_buf \*dmabuf, struct dma_buf_map \*map)
+ *      void \*dma_buf_vmap(struct dma_buf \*dmabuf, struct iosys_map \*map)
+ *      void dma_buf_vunmap(struct dma_buf \*dmabuf, struct iosys_map \*map)
  *
  *   The vmap call can fail if there is no vmap support in the exporter, or if
  *   it runs out of vmalloc space. Note that the dma-buf layer keeps a reference
@@ -1260,12 +1260,12 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF);
  *
  * Returns 0 on success, or a negative errno code otherwise.
  */
-int dma_buf_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
-	struct dma_buf_map ptr;
+	struct iosys_map ptr;
 	int ret = 0;
 
-	dma_buf_map_clear(map);
+	iosys_map_clear(map);
 
 	if (WARN_ON(!dmabuf))
 		return -EINVAL;
@@ -1276,12 +1276,12 @@ int dma_buf_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 	mutex_lock(&dmabuf->lock);
 	if (dmabuf->vmapping_counter) {
 		dmabuf->vmapping_counter++;
-		BUG_ON(dma_buf_map_is_null(&dmabuf->vmap_ptr));
+		BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr));
 		*map = dmabuf->vmap_ptr;
 		goto out_unlock;
 	}
 
-	BUG_ON(dma_buf_map_is_set(&dmabuf->vmap_ptr));
+	BUG_ON(iosys_map_is_set(&dmabuf->vmap_ptr));
 
 	ret = dmabuf->ops->vmap(dmabuf, &ptr);
 	if (WARN_ON_ONCE(ret))
@@ -1303,20 +1303,20 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_vmap, DMA_BUF);
  * @dmabuf:	[in]	buffer to vunmap
  * @map:	[in]	vmap pointer to vunmap
  */
-void dma_buf_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	if (WARN_ON(!dmabuf))
 		return;
 
-	BUG_ON(dma_buf_map_is_null(&dmabuf->vmap_ptr));
+	BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr));
 	BUG_ON(dmabuf->vmapping_counter == 0);
-	BUG_ON(!dma_buf_map_is_equal(&dmabuf->vmap_ptr, map));
+	BUG_ON(!iosys_map_is_equal(&dmabuf->vmap_ptr, map));
 
 	mutex_lock(&dmabuf->lock);
 	if (--dmabuf->vmapping_counter == 0) {
 		if (dmabuf->ops->vunmap)
 			dmabuf->ops->vunmap(dmabuf, map);
-		dma_buf_map_clear(&dmabuf->vmap_ptr);
+		iosys_map_clear(&dmabuf->vmap_ptr);
 	}
 	mutex_unlock(&dmabuf->lock);
 }
diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
index 83f02bd51dda..28fb04eccdd0 100644
--- a/drivers/dma-buf/heaps/cma_heap.c
+++ b/drivers/dma-buf/heaps/cma_heap.c
@@ -202,7 +202,7 @@ static void *cma_heap_do_vmap(struct cma_heap_buffer *buffer)
 	return vaddr;
 }
 
-static int cma_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+static int cma_heap_vmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	struct cma_heap_buffer *buffer = dmabuf->priv;
 	void *vaddr;
@@ -211,7 +211,7 @@ static int cma_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 	mutex_lock(&buffer->lock);
 	if (buffer->vmap_cnt) {
 		buffer->vmap_cnt++;
-		dma_buf_map_set_vaddr(map, buffer->vaddr);
+		iosys_map_set_vaddr(map, buffer->vaddr);
 		goto out;
 	}
 
@@ -222,14 +222,14 @@ static int cma_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 	}
 	buffer->vaddr = vaddr;
 	buffer->vmap_cnt++;
-	dma_buf_map_set_vaddr(map, buffer->vaddr);
+	iosys_map_set_vaddr(map, buffer->vaddr);
 out:
 	mutex_unlock(&buffer->lock);
 
 	return ret;
 }
 
-static void cma_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+static void cma_heap_vunmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	struct cma_heap_buffer *buffer = dmabuf->priv;
 
@@ -239,7 +239,7 @@ static void cma_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 		buffer->vaddr = NULL;
 	}
 	mutex_unlock(&buffer->lock);
-	dma_buf_map_clear(map);
+	iosys_map_clear(map);
 }
 
 static void cma_heap_dma_buf_release(struct dma_buf *dmabuf)
diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c
index ab7fd896d2c4..fcf836ba9c1f 100644
--- a/drivers/dma-buf/heaps/system_heap.c
+++ b/drivers/dma-buf/heaps/system_heap.c
@@ -241,7 +241,7 @@ static void *system_heap_do_vmap(struct system_heap_buffer *buffer)
 	return vaddr;
 }
 
-static int system_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+static int system_heap_vmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	struct system_heap_buffer *buffer = dmabuf->priv;
 	void *vaddr;
@@ -250,7 +250,7 @@ static int system_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 	mutex_lock(&buffer->lock);
 	if (buffer->vmap_cnt) {
 		buffer->vmap_cnt++;
-		dma_buf_map_set_vaddr(map, buffer->vaddr);
+		iosys_map_set_vaddr(map, buffer->vaddr);
 		goto out;
 	}
 
@@ -262,14 +262,14 @@ static int system_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 
 	buffer->vaddr = vaddr;
 	buffer->vmap_cnt++;
-	dma_buf_map_set_vaddr(map, buffer->vaddr);
+	iosys_map_set_vaddr(map, buffer->vaddr);
 out:
 	mutex_unlock(&buffer->lock);
 
 	return ret;
 }
 
-static void system_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+static void system_heap_vunmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	struct system_heap_buffer *buffer = dmabuf->priv;
 
@@ -279,7 +279,7 @@ static void system_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 		buffer->vaddr = NULL;
 	}
 	mutex_unlock(&buffer->lock);
-	dma_buf_map_clear(map);
+	iosys_map_clear(map);
 }
 
 static void system_heap_dma_buf_release(struct dma_buf *dmabuf)