gpu: ion: use vmalloc to allocate page array to map kernel

When ion_map_kernel is execute the system must allocate
an array large enough to hold a pointer to each page in
the buffer.  If the buffer is very large and the system
memory has become very fragmented, there may not be
sufficient high order allocations available from kmalloc.
Use vmalloc instead.

Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c
index 25b02556076ad9b5a70015250e80de43ec8f9141..fcfbb661f2df200fc7ae6c009143bb212a025e9a 100644 (file)
--- a/drivers/staging/android/ion/ion_system_heap.c
+++ b/drivers/staging/android/ion/ion_system_heap.c
@@ -174,10 +174,12 @@ void *ion_system_heap_map_kernel(struct ion_heap *heap,
        pgprot_t pgprot;
        struct sg_table *table = buffer->priv_virt;
        int npages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;
-       struct page **pages = kzalloc(sizeof(struct page *) * npages,
-                                    GFP_KERNEL);
+       struct page **pages = vmalloc(sizeof(struct page *) * npages);
        struct page **tmp = pages;
 
+       if (!pages)
+               return 0;
+
        if (buffer->flags & ION_FLAG_CACHED)
                pgprot = PAGE_KERNEL;
        else
@@ -192,7 +194,7 @@ void *ion_system_heap_map_kernel(struct ion_heap *heap,
                }
        }
        vaddr = vmap(pages, npages, VM_MAP, pgprot);
-       kfree(pages);
+       vfree(pages);
 
        return vaddr;
 }