staging: android: ion: Call dma_map_sg for syncing and mapping

Technically, calling dma_buf_map_attachment should return a buffer
properly dma_mapped. Add calls to dma_map_sg to begin_cpu_access to
ensure this happens. As a side effect, this lets Ion buffers take
advantage of the dma_buf sync ioctls.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index 7dcb8a94de8a452c01f8f39c2f0474334a41d705..6aac935ea19848036fb2f76d23adc0c236dd7921 100644 (file)
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -162,6 +162,7 @@ static struct ion_buffer *ion_buffer_create(struct ion_heap *heap,
        buffer->dev = dev;
        buffer->size = len;
        INIT_LIST_HEAD(&buffer->vmas);
+       INIT_LIST_HEAD(&buffer->attachments);
        mutex_init(&buffer->lock);
        /*
         * this will set up dma addresses for the sglist -- it is not
@@ -796,10 +797,6 @@ void ion_client_destroy(struct ion_client *client)
 }
 EXPORT_SYMBOL(ion_client_destroy);
 
-static void ion_buffer_sync_for_device(struct ion_buffer *buffer,
-                                      struct device *dev,
-                                      enum dma_data_direction direction);
-
 static struct sg_table *dup_sg_table(struct sg_table *table)
 {
        struct sg_table *new_table;
@@ -826,22 +823,89 @@ static struct sg_table *dup_sg_table(struct sg_table *table)
        return new_table;
 }
 
+static void free_duped_table(struct sg_table *table)
+{
+       sg_free_table(table);
+       kfree(table);
+}
+
+struct ion_dma_buf_attachment {
+       struct device *dev;
+       struct sg_table *table;
+       struct list_head list;
+};
+
+static int ion_dma_buf_attach(struct dma_buf *dmabuf, struct device *dev,
+                               struct dma_buf_attachment *attachment)
+{
+       struct ion_dma_buf_attachment *a;
+       struct sg_table *table;
+       struct ion_buffer *buffer = dmabuf->priv;
+
+       a = kzalloc(sizeof(*a), GFP_KERNEL);
+       if (!a)
+               return -ENOMEM;
+
+       table = dup_sg_table(buffer->sg_table);
+       if (IS_ERR(table)) {
+               kfree(a);
+               return -ENOMEM;
+       }
+
+       a->table = table;
+       a->dev = dev;
+       INIT_LIST_HEAD(&a->list);
+
+       attachment->priv = a;
+
+       mutex_lock(&buffer->lock);
+       list_add(&a->list, &buffer->attachments);
+       mutex_unlock(&buffer->lock);
+
+       return 0;
+}
+
+static void ion_dma_buf_detatch(struct dma_buf *dmabuf,
+                               struct dma_buf_attachment *attachment)
+{
+       struct ion_dma_buf_attachment *a = attachment->priv;
+       struct ion_buffer *buffer = dmabuf->priv;
+
+       free_duped_table(a->table);
+       mutex_lock(&buffer->lock);
+       list_del(&a->list);
+       mutex_unlock(&buffer->lock);
+
+       kfree(a);
+}
+
+
 static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,
                                        enum dma_data_direction direction)
 {
-       struct dma_buf *dmabuf = attachment->dmabuf;
-       struct ion_buffer *buffer = dmabuf->priv;
+       struct ion_dma_buf_attachment *a = attachment->priv;
+       struct sg_table *table;
+       int ret;
+
+       table = a->table;
 
-       ion_buffer_sync_for_device(buffer, attachment->dev, direction);
-       return dup_sg_table(buffer->sg_table);
+       if (!dma_map_sg(attachment->dev, table->sgl, table->nents,
+                       direction)){
+               ret = -ENOMEM;
+               goto err;
+       }
+       return table;
+
+err:
+       free_duped_table(table);
+       return ERR_PTR(ret);
 }
 
 static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
                              struct sg_table *table,
                              enum dma_data_direction direction)
 {
-       sg_free_table(table);
-       kfree(table);
+       dma_unmap_sg(attachment->dev, table->sgl, table->nents, direction);
 }
 
 void ion_pages_sync_for_device(struct device *dev, struct page *page,
@@ -865,38 +929,6 @@ struct ion_vma_list {
        struct vm_area_struct *vma;
 };
 
-static void ion_buffer_sync_for_device(struct ion_buffer *buffer,
-                                      struct device *dev,
-                                      enum dma_data_direction dir)
-{
-       struct ion_vma_list *vma_list;
-       int pages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;
-       int i;
-
-       pr_debug("%s: syncing for device %s\n", __func__,
-                dev ? dev_name(dev) : "null");
-
-       if (!ion_buffer_fault_user_mappings(buffer))
-               return;
-
-       mutex_lock(&buffer->lock);
-       for (i = 0; i < pages; i++) {
-               struct page *page = buffer->pages[i];
-
-               if (ion_buffer_page_is_dirty(page))
-                       ion_pages_sync_for_device(dev, ion_buffer_page(page),
-                                                 PAGE_SIZE, dir);
-
-               ion_buffer_page_clean(buffer->pages + i);
-       }
-       list_for_each_entry(vma_list, &buffer->vmas, list) {
-               struct vm_area_struct *vma = vma_list->vma;
-
-               zap_page_range(vma, vma->vm_start, vma->vm_end - vma->vm_start);
-       }
-       mutex_unlock(&buffer->lock);
-}
-
 static int ion_vm_fault(struct vm_fault *vmf)
 {
        struct ion_buffer *buffer = vmf->vma->vm_private_data;
@@ -1014,26 +1046,45 @@ static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
 {
        struct ion_buffer *buffer = dmabuf->priv;
        void *vaddr;
+       struct ion_dma_buf_attachment *a;
 
-       if (!buffer->heap->ops->map_kernel) {
-               pr_err("%s: map kernel is not implemented by this heap.\n",
-                      __func__);
-               return -ENODEV;
+       /*
+        * TODO: Move this elsewhere because we don't always need a vaddr
+        */
+       if (buffer->heap->ops->map_kernel) {
+               mutex_lock(&buffer->lock);
+               vaddr = ion_buffer_kmap_get(buffer);
+               mutex_unlock(&buffer->lock);
        }
 
+
        mutex_lock(&buffer->lock);
-       vaddr = ion_buffer_kmap_get(buffer);
+       list_for_each_entry(a, &buffer->attachments, list) {
+               dma_sync_sg_for_cpu(a->dev, a->table->sgl, a->table->nents,
+                                       DMA_BIDIRECTIONAL);
+       }
        mutex_unlock(&buffer->lock);
-       return PTR_ERR_OR_ZERO(vaddr);
+
+       return 0;
 }
 
 static int ion_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
                                      enum dma_data_direction direction)
 {
        struct ion_buffer *buffer = dmabuf->priv;
+       struct ion_dma_buf_attachment *a;
+
+       if (buffer->heap->ops->map_kernel) {
+               mutex_lock(&buffer->lock);
+               ion_buffer_kmap_put(buffer);
+               mutex_unlock(&buffer->lock);
+       }
 
        mutex_lock(&buffer->lock);
-       ion_buffer_kmap_put(buffer);
+       list_for_each_entry(a, &buffer->attachments, list) {
+               dma_sync_sg_for_device(a->dev, a->table->sgl, a->table->nents,
+                                       DMA_BIDIRECTIONAL);
+       }
        mutex_unlock(&buffer->lock);
 
        return 0;
@@ -1044,6 +1095,8 @@ static const struct dma_buf_ops dma_buf_ops = {
        .unmap_dma_buf = ion_unmap_dma_buf,
        .mmap = ion_mmap,
        .release = ion_dma_buf_release,
+       .attach = ion_dma_buf_attach,
+       .detach = ion_dma_buf_detatch,
        .begin_cpu_access = ion_dma_buf_begin_cpu_access,
        .end_cpu_access = ion_dma_buf_end_cpu_access,
        .kmap_atomic = ion_dma_buf_kmap,

diff --git a/drivers/staging/android/ion/ion_priv.h b/drivers/staging/android/ion/ion_priv.h
index b09bc7cdf2db94486465f7f6f36eeee7f35962f5..297d99d310a92cec09baf7b82104db6ecefdfbae 100644 (file)
--- a/drivers/staging/android/ion/ion_priv.h
+++ b/drivers/staging/android/ion/ion_priv.h
@@ -72,6 +72,7 @@ struct ion_buffer {
        struct sg_table *sg_table;
        struct page **pages;
        struct list_head vmas;
+       struct list_head attachments;
        /* used to track orphaned buffers */
        int handle_count;
        char task_comm[TASK_COMM_LEN];