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

1 files changed, 21 insertions, 21 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_resource.c b/drivers/gpu/drm/ttm/ttm_resource.c
index 035d71332d18..df9efafa0f2f 100644
--- a/drivers/gpu/drm/ttm/ttm_resource.c
+++ b/drivers/gpu/drm/ttm/ttm_resource.c
@@ -22,7 +22,7 @@
  * Authors: Christian König
  */
 
-#include <linux/dma-buf-map.h>
+#include <linux/iosys-map.h>
 #include <linux/io-mapping.h>
 #include <linux/scatterlist.h>
 
@@ -209,7 +209,7 @@ void ttm_resource_manager_debug(struct ttm_resource_manager *man,
 EXPORT_SYMBOL(ttm_resource_manager_debug);
 
 static void ttm_kmap_iter_iomap_map_local(struct ttm_kmap_iter *iter,
-					  struct dma_buf_map *dmap,
+					  struct iosys_map *dmap,
 					  pgoff_t i)
 {
 	struct ttm_kmap_iter_iomap *iter_io =
@@ -236,11 +236,11 @@ retry:
 	addr = io_mapping_map_local_wc(iter_io->iomap, iter_io->cache.offs +
 				       (((resource_size_t)i - iter_io->cache.i)
 					<< PAGE_SHIFT));
-	dma_buf_map_set_vaddr_iomem(dmap, addr);
+	iosys_map_set_vaddr_iomem(dmap, addr);
 }
 
 static void ttm_kmap_iter_iomap_unmap_local(struct ttm_kmap_iter *iter,
-					    struct dma_buf_map *map)
+					    struct iosys_map *map)
 {
 	io_mapping_unmap_local(map->vaddr_iomem);
 }
@@ -291,14 +291,14 @@ EXPORT_SYMBOL(ttm_kmap_iter_iomap_init);
  */
 
 static void ttm_kmap_iter_linear_io_map_local(struct ttm_kmap_iter *iter,
-					      struct dma_buf_map *dmap,
+					      struct iosys_map *dmap,
 					      pgoff_t i)
 {
 	struct ttm_kmap_iter_linear_io *iter_io =
 		container_of(iter, typeof(*iter_io), base);
 
 	*dmap = iter_io->dmap;
-	dma_buf_map_incr(dmap, i * PAGE_SIZE);
+	iosys_map_incr(dmap, i * PAGE_SIZE);
 }
 
 static const struct ttm_kmap_iter_ops ttm_kmap_iter_linear_io_ops = {
@@ -334,7 +334,7 @@ ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
 	}
 
 	if (mem->bus.addr) {
-		dma_buf_map_set_vaddr(&iter_io->dmap, mem->bus.addr);
+		iosys_map_set_vaddr(&iter_io->dmap, mem->bus.addr);
 		iter_io->needs_unmap = false;
 	} else {
 		size_t bus_size = (size_t)mem->num_pages << PAGE_SHIFT;
@@ -342,23 +342,23 @@ ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
 		iter_io->needs_unmap = true;
 		memset(&iter_io->dmap, 0, sizeof(iter_io->dmap));
 		if (mem->bus.caching == ttm_write_combined)
-			dma_buf_map_set_vaddr_iomem(&iter_io->dmap,
-						    ioremap_wc(mem->bus.offset,
-							       bus_size));
+			iosys_map_set_vaddr_iomem(&iter_io->dmap,
+						  ioremap_wc(mem->bus.offset,
+							     bus_size));
 		else if (mem->bus.caching == ttm_cached)
-			dma_buf_map_set_vaddr(&iter_io->dmap,
-					      memremap(mem->bus.offset, bus_size,
-						       MEMREMAP_WB |
-						       MEMREMAP_WT |
-						       MEMREMAP_WC));
+			iosys_map_set_vaddr(&iter_io->dmap,
+					    memremap(mem->bus.offset, bus_size,
+						     MEMREMAP_WB |
+						     MEMREMAP_WT |
+						     MEMREMAP_WC));
 
 		/* If uncached requested or if mapping cached or wc failed */
-		if (dma_buf_map_is_null(&iter_io->dmap))
-			dma_buf_map_set_vaddr_iomem(&iter_io->dmap,
-						    ioremap(mem->bus.offset,
-							    bus_size));
+		if (iosys_map_is_null(&iter_io->dmap))
+			iosys_map_set_vaddr_iomem(&iter_io->dmap,
+						  ioremap(mem->bus.offset,
+							  bus_size));
 
-		if (dma_buf_map_is_null(&iter_io->dmap)) {
+		if (iosys_map_is_null(&iter_io->dmap)) {
 			ret = -ENOMEM;
 			goto out_io_free;
 		}
@@ -387,7 +387,7 @@ ttm_kmap_iter_linear_io_fini(struct ttm_kmap_iter_linear_io *iter_io,
 			     struct ttm_device *bdev,
 			     struct ttm_resource *mem)
 {
-	if (iter_io->needs_unmap && dma_buf_map_is_set(&iter_io->dmap)) {
+	if (iter_io->needs_unmap && iosys_map_is_set(&iter_io->dmap)) {
 		if (iter_io->dmap.is_iomem)
 			iounmap(iter_io->dmap.vaddr_iomem);
 		else