[PATCH 110/115] ion: add helper to zero contiguous region of pages

John Stultz
2013-12-14T03:27:58Z

From: Colin Cross <ccross@android.com>

Add ion_heap_pages_zero for ion heaps to use to zero pages
during initialization or allocation, when a struct ion_buffer
may not be available. Use it from the chunk heap and carveout
heaps.

Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
drivers/staging/android/ion/ion_carveout_heap.c | 13 ++++++
drivers/staging/android/ion/ion_chunk_heap.c | 39 ++++++------------
drivers/staging/android/ion/ion_heap.c | 53 +++++++++++++++----------
drivers/staging/android/ion/ion_priv.h | 1 +
4 files changed, 58 insertions(+), 48 deletions(-)

diff --git a/drivers/staging/android/ion/ion_carveout_heap.c b/drivers/staging/android/ion/ion_carveout_heap.c
index 66dec4c..3cb05b9 100644
--- a/drivers/staging/android/ion/ion_carveout_heap.c
+++ b/drivers/staging/android/ion/ion_carveout_heap.c
@@ -150,6 +150,19 @@ static struct ion_heap_ops carveout_heap_ops = {
struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *heap_data)
{
struct ion_carveout_heap *carveout_heap;
+ int ret;
+
+ struct page *page;
+ size_t size;
+
+ page = pfn_to_page(PFN_DOWN(heap_data->base));
+ size = heap_data->size;
+
+ ion_pages_sync_for_device(NULL, page, size, DMA_BIDIRECTIONAL);
+
+ ret = ion_heap_pages_zero(page, size, pgprot_writecombine(PAGE_KERNEL));
+ if (ret)
+ return ERR_PTR(ret);

carveout_heap = kzalloc(sizeof(struct ion_carveout_heap), GFP_KERNEL);
if (!carveout_heap)
diff --git a/drivers/staging/android/ion/ion_chunk_heap.c b/drivers/staging/android/ion/ion_chunk_heap.c
index 46e8a3b..f21530f 100644
--- a/drivers/staging/android/ion/ion_chunk_heap.c
+++ b/drivers/staging/android/ion/ion_chunk_heap.c
@@ -140,9 +140,18 @@ static struct ion_heap_ops chunk_heap_ops = {
struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *heap_data)
{
struct ion_chunk_heap *chunk_heap;
- struct vm_struct *vm_struct;
- pgprot_t pgprot = pgprot_writecombine(PAGE_KERNEL);
- int i, ret;
+ int ret;
+ struct page *page;
+ size_t size;
+
+ page = pfn_to_page(PFN_DOWN(heap_data->base));
+ size = heap_data->size;
+
+ ion_pages_sync_for_device(NULL, page, size, DMA_BIDIRECTIONAL);
+
+ ret = ion_heap_pages_zero(page, size, pgprot_writecombine(PAGE_KERNEL));
+ if (ret)
+ return ERR_PTR(ret);

chunk_heap = kzalloc(sizeof(struct ion_chunk_heap), GFP_KERNEL);
if (!chunk_heap)
@@ -159,26 +168,6 @@ struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *heap_data)
chunk_heap->size = heap_data->size;
chunk_heap->allocated = 0;

- vm_struct = get_vm_area(PAGE_SIZE, VM_ALLOC);
- if (!vm_struct) {
- ret = -ENOMEM;
- goto error;
- }
- for (i = 0; i < chunk_heap->size; i += PAGE_SIZE) {
- struct page *page = pfn_to_page(PFN_DOWN(chunk_heap->base + i));
- struct page **pages = &page;
-
- ret = map_vm_area(vm_struct, pgprot, &pages);
- if (ret)
- goto error_map_vm_area;
- memset(vm_struct->addr, 0, PAGE_SIZE);
- unmap_kernel_range((unsigned long)vm_struct->addr, PAGE_SIZE);
- }
- free_vm_area(vm_struct);
-
- ion_pages_sync_for_device(NULL, pfn_to_page(PFN_DOWN(heap_data->base)),
- heap_data->size, DMA_BIDIRECTIONAL);
-
gen_pool_add(chunk_heap->pool, chunk_heap->base, heap_data->size, -1);
chunk_heap->heap.ops = &chunk_heap_ops;
chunk_heap->heap.type = ION_HEAP_TYPE_CHUNK;
@@ -188,10 +177,6 @@ struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *heap_data)

return &chunk_heap->heap;

-error_map_vm_area:
- free_vm_area(vm_struct);
-error:
- gen_pool_destroy(chunk_heap->pool);
error_gen_pool_create:
kfree(chunk_heap);
return ERR_PTR(ret);
diff --git a/drivers/staging/android/ion/ion_heap.c b/drivers/staging/android/ion/ion_heap.c
index c3a213b..2d1d555 100644
--- a/drivers/staging/android/ion/ion_heap.c
+++ b/drivers/staging/android/ion/ion_heap.c
@@ -114,38 +114,49 @@ static int ion_heap_clear_pages(struct page **pages, int num, pgprot_t pgprot)
return 0;
}

+static int ion_heap_sglist_zero(struct scatterlist *sgl, unsigned int nents,
+ pgprot_t pgprot)
+{
+ int p = 0;
+ int ret = 0;
+ struct sg_page_iter piter;
+ struct page *pages[32];
+
+ for_each_sg_page(sgl, &piter, nents, 0) {
+ pages[p++] = sg_page_iter_page(&piter);
+ if (p == ARRAY_SIZE(pages)) {
+ ret = ion_heap_clear_pages(pages, p, pgprot);
+ if (ret)
+ return ret;
+ p = 0;
+ }
+ }
+ if (p)
+ ret = ion_heap_clear_pages(pages, p, pgprot);
+
+ return ret;
+}
+
int ion_heap_buffer_zero(struct ion_buffer *buffer)
{
struct sg_table *table = buffer->sg_table;
pgprot_t pgprot;
- struct scatterlist *sg;
- int i, j, ret = 0;
- struct page *pages[32];
- int k = 0;

if (buffer->flags & ION_FLAG_CACHED)
pgprot = PAGE_KERNEL;
else
pgprot = pgprot_writecombine(PAGE_KERNEL);

- for_each_sg(table->sgl, sg, table->nents, i) {
- struct page *page = sg_page(sg);
- unsigned long len = sg->length;
+ return ion_heap_sglist_zero(table->sgl, table->nents, pgprot);
+}

- for (j = 0; j < len / PAGE_SIZE; j++) {
- pages[k++] = page + j;
- if (k == ARRAY_SIZE(pages)) {
- ret = ion_heap_clear_pages(pages, k, pgprot);
- if (ret)
- goto end;
- k = 0;
- }
- }
- if (k)
- ret = ion_heap_clear_pages(pages, k, pgprot);
- }
-end:
- return ret;
+int ion_heap_pages_zero(struct page *page, size_t size, pgprot_t pgprot)
+{
+ struct scatterlist sg;
+
+ sg_init_table(&sg, 1);
+ sg_set_page(&sg, page, size, 0);
+ return ion_heap_sglist_zero(&sg, 1, pgprot);
}

void ion_heap_freelist_add(struct ion_heap *heap, struct ion_buffer * buffer)
diff --git a/drivers/staging/android/ion/ion_priv.h b/drivers/staging/android/ion/ion_priv.h
index c9b507d..fa96175 100644
--- a/drivers/staging/android/ion/ion_priv.h
+++ b/drivers/staging/android/ion/ion_priv.h
@@ -215,6 +215,7 @@ void ion_heap_unmap_kernel(struct ion_heap *, struct ion_buffer *);
int ion_heap_map_user(struct ion_heap *, struct ion_buffer *,
struct vm_area_struct *);
int ion_heap_buffer_zero(struct ion_buffer *buffer);
+int ion_heap_pages_zero(struct page *page, size_t size, pgprot_t pgprot);

/**
* ion_heap_init_deferred_free -- initialize deferred free functionality
--
1.8.3.2