gpu: nvgpu: Remove <linux/mm.h> from the page allocator

Remove the <linux/mm.h> include from the VIDMEM page allocator. To
do this PAGE_SIZE needed to be defined for VIDMEM. Technically using
the Linux PAGE_SIZE macro for VIDMEM was a bug since PAGE_SIZE need
not be 4K on Linux so this patch also fixes a theoretical bug.

Also usage of ERR_PTR(), PTR_ERR() and IS_ERR() was removed. These
are Linux specific error handling macros.

Change-Id: Iadaf5b8e0154b0c3adf593449023005afffad90d
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: http://git-master/r/1472371
Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 24 insertions, 10 deletions

diff --git a/drivers/gpu/nvgpu/common/mm/page_allocator.c b/drivers/gpu/nvgpu/common/mm/page_allocator.c
index 2ffff63d..14b5da3c 100644
--- a/drivers/gpu/nvgpu/common/mm/page_allocator.c
+++ b/drivers/gpu/nvgpu/common/mm/page_allocator.c
@@ -14,8 +14,6 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <linux/mm.h>
-
 #include <nvgpu/bitops.h>
 #include <nvgpu/allocator.h>
 #include <nvgpu/page_allocator.h>
@@ -29,6 +27,22 @@
         alloc_dbg(palloc_owner(a), fmt, ##arg)
 
 /*
+ * Since some Linux headers are still leaked into common code this is necessary
+ * for some builds.
+ */
+#ifdef PAGE_SIZE
+#undef PAGE_SIZE
+#undef PAGE_ALIGN
+#endif
+
+/*
+ * VIDMEM page size is 4k.
+ */
+#define PAGE_SIZE               0x1000
+#define PAGE_ALIGN(addr)        ((addr + (PAGE_SIZE - 1)) &             \
+                                 ((typeof(addr)) ~(PAGE_SIZE - 1)))
+
+/*
  * Handle the book-keeping for these operations.
  */
 static inline void add_slab_page_to_empty(struct page_alloc_slab *slab,
@@ -186,7 +200,7 @@ static struct page_alloc_slab_page *alloc_slab_page(
         slab_page = nvgpu_kmem_cache_alloc(a->slab_page_cache);
         if (!slab_page) {
                 palloc_dbg(a, "OOM: unable to alloc slab_page struct!\n");
-                return ERR_PTR(-ENOMEM);
+                return NULL;
         }
 
         memset(slab_page, 0, sizeof(*slab_page));
@@ -195,7 +209,7 @@ static struct page_alloc_slab_page *alloc_slab_page(
         if (!slab_page->page_addr) {
                 nvgpu_kmem_cache_free(a->slab_page_cache, slab_page);
                 palloc_dbg(a, "OOM: vidmem is full!\n");
-                return ERR_PTR(-ENOMEM);
+                return NULL;
         }
 
         nvgpu_init_list_node(&slab_page->list_entry);
@@ -259,8 +273,8 @@ static int __do_slab_alloc(struct nvgpu_page_allocator *a,
 
         if (!slab_page) {
                 slab_page = alloc_slab_page(a, slab);
-                if (IS_ERR(slab_page))
-                        return PTR_ERR(slab_page);
+                if (!slab_page)
+                        return -ENOMEM;
         }
 
         /*
@@ -500,7 +514,7 @@ fail_cleanup:
         }
         nvgpu_kmem_cache_free(a->alloc_cache, alloc);
 fail:
-        return ERR_PTR(-ENOMEM);
+        return NULL;
 }
 
 static struct nvgpu_page_alloc *__nvgpu_alloc_pages(
@@ -514,7 +528,7 @@ static struct nvgpu_page_alloc *__nvgpu_alloc_pages(
         pages = ALIGN(len, a->page_size) >> a->page_shift;
 
         alloc = __do_nvgpu_alloc_pages(a, pages);
-        if (IS_ERR(alloc)) {
+        if (!alloc) {
                 palloc_dbg(a, "Alloc 0x%llx (%llu) (failed)\n",
                            pages << a->page_shift, pages);
                 return NULL;
@@ -652,7 +666,7 @@ fail:
                 nvgpu_kmem_cache_free(a->chunk_cache, c);
         if (alloc)
                 nvgpu_kmem_cache_free(a->alloc_cache, alloc);
-        return ERR_PTR(-ENOMEM);
+        return NULL;
 }
 
 /*
@@ -673,7 +687,7 @@ static u64 nvgpu_page_alloc_fixed(struct nvgpu_allocator *__a,
         alloc_lock(__a);
 
         alloc = __nvgpu_alloc_pages_fixed(a, base, aligned_len, 0);
-        if (IS_ERR(alloc)) {
+        if (!alloc) {
                 alloc_unlock(__a);
                 return 0;
         }