video: tegra: nvmap: eliminate arm_attrib_allocator dependency

remove the dependency that nvmap has on the arm_attrib_allocator
and the lowmem in PTEs change by adding a private page allocator
utility function and calling vm_map_ram unconditionally for all
sysmem handles.

also, add Kconfig variables to allow platforms to disallow the
SYSMEM heap, and to optionally restrict the SYSMEM and IOVMM
heaps to just HIGHMEM.

Change-Id: I3dab1c7323f54a8ab3994dc672b27fd79a9057d7
Signed-off-by: Gary King <gking@nvidia.com>

drivers/video/tegra/Kconfig

@@ -28,22 +28,38 @@ config FB_TEGRA
 	  Framebuffer device support for the Tegra display controller.
 
 config TEGRA_NVMAP
-	bool "Tegra GPU memory management driver"
-	select ARM_ATTRIB_ALLOCATOR
+	bool "Tegra GPU memory management driver (nvmap)"
 	default y
 	help
 	  Say Y here to include the memory management driver for the Tegra
 	  GPU, multimedia and display subsystems
 
 config NVMAP_RECLAIM_UNPINNED_VM
-	bool "Allow /dev/nvmap to reclaim unpinned I/O virtual memory"
+	bool "Virtualize IOVMM memory in nvmap"
 	depends on TEGRA_NVMAP && TEGRA_IOVMM
 	default y
 	help
-	  Say Y here to enable /dev/nvmap to reclaim I/O virtual memory after
-	  it has been unpinned, and re-use it for other objects. This can
+	  Say Y here to enable nvmap to reclaim I/O virtual memory after
+	  it has been unpinned, and re-use it for other handles. This can
 	  allow a larger virtual I/O VM space than would normally be
 	  supported by the hardware, at a slight cost in performance.
 
+config NVMAP_ALLOW_SYSMEM
+	bool "Allow physical system memory to be used by nvmap"
+	depends on TEGRA_NVMAP
+	default y
+	help
+	  Say Y here to allow nvmap to use physical system memory (i.e.,
+	  shared with the operating system but not translated through
+	  an IOVMM device) for allocations.
+
+config NVMAP_HIGHMEM_ONLY
+	bool "Use only HIGHMEM for nvmap"
+	depends on TEGRA_NVMAP && (NVMAP_ALLOW_SYSMEM || TEGRA_IOVMM) && HIGHMEM
+	default n
+	help
+	  Say Y here to restrict nvmap system memory allocations (both
+	  physical system memory and IOVMM) to just HIGHMEM pages.
+
 endif
 

drivers/video/tegra/nvmap/nvmap.c

@@ -623,10 +623,7 @@ void *nvmap_mmap(struct nvmap_handle_ref *ref)
 
 	prot = nvmap_pgprot(h, pgprot_kernel);
 
-	if (h->heap_pgalloc && h->pgalloc.contig &&
-	    !PageHighMem(h->pgalloc.pages[0]))
-		return page_address(h->pgalloc.pages[0]);
-	else if (h->heap_pgalloc)
+	if (h->heap_pgalloc)
 		return vm_map_ram(h->pgalloc.pages, h->size >> PAGE_SHIFT,
 				  -1, prot);
 
@@ -687,10 +684,9 @@ void nvmap_munmap(struct nvmap_handle_ref *ref, void *addr)
 
 	h = ref->handle;
 
-	if (h->heap_pgalloc && (!h->pgalloc.contig ||
-				PageHighMem(h->pgalloc.pages[0]))) {
+	if (h->heap_pgalloc) {
 		vm_unmap_ram(addr, h->size >> PAGE_SHIFT);
-	} else if (!h->heap_pgalloc) {
+	} else {
 		struct vm_struct *vm;
 		addr -= (h->carveout->base & ~PAGE_MASK);
 		vm = remove_vm_area(addr);

drivers/video/tegra/nvmap/nvmap_handle.c

@@ -28,7 +28,8 @@
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 
-#include <asm/attrib_alloc.h>
+#include <asm/cacheflush.h>
+#include <asm/outercache.h>
 #include <asm/pgtable.h>
 
 #include <mach/iovmm.h>
@@ -38,7 +39,11 @@
 #include "nvmap_mru.h"
 
 #define NVMAP_SECURE_HEAPS	(NVMAP_HEAP_CARVEOUT_IRAM | NVMAP_HEAP_IOVMM)
+#ifdef CONFIG_NVMAP_HIGHMEM_ONLY
 #define GFP_NVMAP		(__GFP_HIGHMEM | __GFP_NOWARN)
+#else
+#define GFP_NVMAP		(GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN)
+#endif
 /* handles may be arbitrarily large (16+MiB), and any handle allocated from
  * the kernel (i.e., not a carveout handle) includes its array of pages. to
  * preserve kmalloc space, if the array of pages exceeds PAGELIST_VMALLOC_MIN,
@@ -90,7 +95,7 @@ void _nvmap_handle_free(struct nvmap_handle *h)
 		tegra_iovmm_free_vm(h->pgalloc.area);
 
 	for (i = 0; i < nr_page; i++)
-		arm_attrib_free_page(h->pgalloc.pages[i]);
+		__free_page(h->pgalloc.pages[i]);
 
 	altfree(h->pgalloc.pages, nr_page * sizeof(struct page *));
 
@@ -99,6 +104,36 @@ out:
 	nvmap_client_put(client);
 }
 
+extern void __flush_dcache_page(struct address_space *, struct page *);
+
+static struct page *nvmap_alloc_pages_exact(gfp_t gfp, size_t size)
+{
+	struct page *page, *p, *e;
+	unsigned int order;
+	unsigned long base;
+
+	size = PAGE_ALIGN(size);
+	order = get_order(size);
+	page = alloc_pages(gfp, order);
+
+	if (!page)
+		return NULL;
+
+	split_page(page, order);
+
+	e = page + (1 << order);
+	for (p = page + (size >> PAGE_SHIFT); p < e; p++)
+		__free_page(p);
+
+	e = page + (size >> PAGE_SHIFT);
+	for (p = page; p < e; p++)
+		__flush_dcache_page(page_mapping(p), p);
+
+	base = page_to_phys(page);
+	outer_flush_range(base, base + size);
+	return page;
+}
+
 static int handle_page_alloc(struct nvmap_client *client,
 			     struct nvmap_handle *h, bool contiguous)
 {
@@ -120,14 +155,16 @@ static int handle_page_alloc(struct nvmap_client *client,
 	h->pgalloc.area = NULL;
 	if (contiguous) {
 		struct page *page;
-		page = arm_attrib_alloc_pages_exact(GFP_NVMAP, size, prot);
+		page = nvmap_alloc_pages_exact(GFP_NVMAP, size);
+		if (!page)
+			goto fail;
 
 		for (i = 0; i < nr_page; i++)
 			pages[i] = nth_page(page, i);
 
 	} else {
 		for (i = 0; i < nr_page; i++) {
-			pages[i] = arm_attrib_alloc_page(GFP_NVMAP, prot);
+			pages[i] = nvmap_alloc_pages_exact(GFP_NVMAP, PAGE_SIZE);
 			if (!pages[i])
 				goto fail;
 		}
@@ -151,7 +188,7 @@ static int handle_page_alloc(struct nvmap_client *client,
 
 fail:
 	while (i--)
-		arm_attrib_free_page(pages[i]);
+		__free_page(pages[i]);
 	altfree(pages, nr_page * sizeof(*pages));
 	return -ENOMEM;
 }
@@ -210,7 +247,9 @@ static void alloc_handle(struct nvmap_client *client, size_t align,
  * sub-page splinters */
 static const unsigned int heap_policy_small[] = {
 	NVMAP_HEAP_CARVEOUT_IRAM,
+#ifdef CONFIG_NVMAP_ALLOW_SYSMEM
 	NVMAP_HEAP_SYSMEM,
+#endif
 	NVMAP_HEAP_CARVEOUT_MASK,
 	NVMAP_HEAP_IOVMM,
 	0,
@@ -220,7 +259,9 @@ static const unsigned int heap_policy_large[] = {
 	NVMAP_HEAP_CARVEOUT_IRAM,
 	NVMAP_HEAP_IOVMM,
 	NVMAP_HEAP_CARVEOUT_MASK,
+#ifdef CONFIG_NVMAP_ALLOW_SYSMEM
 	NVMAP_HEAP_SYSMEM,
+#endif
 	0,
 };