msm: kgsl: Create scatter gather lists for memory objects

Create and use scatter-gather lists for memory objects, which
avoids dynamically figuring the physical addresses of pages for
MMU mapping and cache operations.

Change-Id: Ic0dedbad9b973ecce4ae773b6bd682ba01010e5b
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
diff --git a/drivers/gpu/msm/kgsl_sharedmem.h b/drivers/gpu/msm/kgsl_sharedmem.h
index 9e57e78..a9abcf9 100644
--- a/drivers/gpu/msm/kgsl_sharedmem.h
+++ b/drivers/gpu/msm/kgsl_sharedmem.h
@@ -13,6 +13,7 @@
 #ifndef __KGSL_SHAREDMEM_H
 #define __KGSL_SHAREDMEM_H
 
+#include <linux/slab.h>
 #include <linux/dma-mapping.h>
 
 struct kgsl_device;
@@ -26,8 +27,6 @@
 #define KGSL_MEMFLAGS_CACHED    0x00000001
 
 struct kgsl_memdesc_ops {
-	unsigned long (*physaddr)(struct kgsl_memdesc *, unsigned int);
-	void (*outer_cache)(struct kgsl_memdesc *, int);
 	int (*vmflags)(struct kgsl_memdesc *);
 	int (*vmfault)(struct kgsl_memdesc *, struct vm_area_struct *,
 		       struct vm_fault *);
@@ -35,8 +34,6 @@
 };
 
 extern struct kgsl_memdesc_ops kgsl_vmalloc_ops;
-extern struct kgsl_memdesc_ops kgsl_contiguous_ops;
-extern struct kgsl_memdesc_ops kgsl_userptr_ops;
 
 int kgsl_sharedmem_vmalloc(struct kgsl_memdesc *memdesc,
 			   struct kgsl_pagetable *pagetable, size_t size);
@@ -78,6 +75,22 @@
 void kgsl_sharedmem_uninit_sysfs(void);
 
 static inline int
+memdesc_sg_phys(struct kgsl_memdesc *memdesc,
+		unsigned int physaddr, unsigned int size)
+{
+	struct page *page = phys_to_page(physaddr);
+
+	memdesc->sg = kmalloc(sizeof(struct scatterlist) * 1, GFP_KERNEL);
+	if (memdesc->sg == NULL)
+		return -ENOMEM;
+
+	memdesc->sglen = 1;
+	sg_init_table(memdesc->sg, 1);
+	sg_set_page(&memdesc->sg[0], page, size, 0);
+	return 0;
+}
+
+static inline int
 kgsl_allocate(struct kgsl_memdesc *memdesc,
 		struct kgsl_pagetable *pagetable, size_t size)
 {