@@ -35,7 +35,7 @@ struct system_heap_buffer {
struct dma_heap_attachment {
struct device *dev;
- struct sg_table *table;
+ struct sg_table table;
struct list_head list;
bool mapped;
};
@@ -54,29 +54,22 @@ static gfp_t order_flags[] = {HIGH_ORDER_GFP, HIGH_ORDER_GFP, LOW_ORDER_GFP};
static const unsigned int orders[] = {8, 4, 0};
#define NUM_ORDERS ARRAY_SIZE(orders)
-static struct sg_table *dup_sg_table(struct sg_table *table)
+static int dup_sg_table(struct sg_table *from, struct sg_table *to)
{
- struct sg_table *new_table;
- int ret, i;
struct scatterlist *sg, *new_sg;
+ int ret, i;
- new_table = kzalloc(sizeof(*new_table), GFP_KERNEL);
- if (!new_table)
- return ERR_PTR(-ENOMEM);
-
- ret = sg_alloc_table(new_table, table->orig_nents, GFP_KERNEL);
- if (ret) {
- kfree(new_table);
- return ERR_PTR(-ENOMEM);
- }
+ ret = sg_alloc_table(to, from->orig_nents, GFP_KERNEL);
+ if (ret)
+ return ret;
- new_sg = new_table->sgl;
- for_each_sgtable_sg(table, sg, i) {
+ new_sg = to->sgl;
+ for_each_sgtable_sg(from, sg, i) {
sg_set_page(new_sg, sg_page(sg), sg->length, sg->offset);
new_sg = sg_next(new_sg);
}
- return new_table;
+ return 0;
}
static int system_heap_attach(struct dma_buf *dmabuf,
@@ -84,19 +77,18 @@ static int system_heap_attach(struct dma_buf *dmabuf,
{
struct system_heap_buffer *buffer = dmabuf->priv;
struct dma_heap_attachment *a;
- struct sg_table *table;
+ int ret;
a = kzalloc(sizeof(*a), GFP_KERNEL);
if (!a)
return -ENOMEM;
- table = dup_sg_table(&buffer->sg_table);
- if (IS_ERR(table)) {
+ ret = dup_sg_table(&buffer->sg_table, &a->table);
+ if (ret) {
kfree(a);
- return -ENOMEM;
+ return ret;
}
- a->table = table;
a->dev = attachment->dev;
INIT_LIST_HEAD(&a->list);
a->mapped = false;
@@ -120,8 +112,7 @@ static void system_heap_detach(struct dma_buf *dmabuf,
list_del(&a->list);
mutex_unlock(&buffer->lock);
- sg_free_table(a->table);
- kfree(a->table);
+ sg_free_table(&a->table);
kfree(a);
}
@@ -129,7 +120,7 @@ static struct sg_table *system_heap_map_dma_buf(struct dma_buf_attachment *attac
enum dma_data_direction direction)
{
struct dma_heap_attachment *a = attachment->priv;
- struct sg_table *table = a->table;
+ struct sg_table *table = &a->table;
int ret;
ret = dma_map_sgtable(attachment->dev, table, direction, 0);
@@ -164,7 +155,7 @@ static int system_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
list_for_each_entry(a, &buffer->attachments, list) {
if (!a->mapped)
continue;
- dma_sync_sgtable_for_cpu(a->dev, a->table, direction);
+ dma_sync_sgtable_for_cpu(a->dev, &a->table, direction);
}
mutex_unlock(&buffer->lock);
@@ -185,7 +176,7 @@ static int system_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
list_for_each_entry(a, &buffer->attachments, list) {
if (!a->mapped)
continue;
- dma_sync_sgtable_for_device(a->dev, a->table, direction);
+ dma_sync_sgtable_for_device(a->dev, &a->table, direction);
}
mutex_unlock(&buffer->lock);
struct dma_heap_attachment is a separate allocation from the struct sg_table it contains, but there is no reason for this. Let's use the slab allocator just once instead of twice for dma_heap_attachment. Signed-off-by: T.J. Mercier <tjmercier@google.com> --- drivers/dma-buf/heaps/system_heap.c | 43 ++++++++++++----------------- 1 file changed, 17 insertions(+), 26 deletions(-) base-commit: 8ffd015db85fea3e15a77027fda6c02ced4d2444