gpu: ion: Switch to using kmalloc rather than kmap during allocation

Previously, metadata was stored in the allocated pages themselves
during allocation.  However the system can only have a limited
number of kmapped pages.  A very large allocation might exceed
this limit.

Change-Id: Ibe972096e83924bf5e621d8282c4cd133ca75b0a
Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>

diff --git a/drivers/gpu/ion/ion_system_heap.c b/drivers/gpu/ion/ion_system_heap.c
index e7fb07d45a2aa77a9dca0d89302a619b1303b987..ca6de04f6c29ff202ec7510471ee051e22449105 100644 (file)
--- a/drivers/gpu/ion/ion_system_heap.c
+++ b/drivers/gpu/ion/ion_system_heap.c
@@ -46,7 +46,7 @@ static struct page_info *alloc_largest_available(unsigned long size)
                if (!page)
                        continue;
                split_page(page, orders[i]);
-               info = kmap(page);
+               info = kmalloc(sizeof(struct page_info *), GFP_KERNEL);
                info->page = page;
                info->order = orders[i];
                return info;
@@ -93,7 +93,7 @@ static int ion_system_heap_allocate(struct ion_heap *heap,
                }
                list_del(&info->list);
                memset(info, 0, sizeof(struct page_info));
-               kunmap(page);
+               kfree(info);
        }
 
        dma_sync_sg_for_device(NULL, table->sgl, table->nents,
@@ -107,7 +107,7 @@ err:
        list_for_each_entry(info, &pages, list) {
                for (i = 0; i < (1 << info->order); i++)
                        __free_page(info->page + i);
-               kunmap(info->page);
+               kfree(info);
        }
        return -ENOMEM;
 }