[RFC PATCH 05/12] staging: android: ion: Remove page faulting support

Laura Abbott
2017-03-02T21:44:37Z

The new method of syncing with dma_map means that the page faulting sync
implementation is no longer applicable. Remove it.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
drivers/staging/android/ion/ion.c | 117 --------------------------------------
1 file changed, 117 deletions(-)

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index a931b30..8eef1d7 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -41,37 +41,11 @@
#include "ion_priv.h"
#include "compat_ion.h"

-bool ion_buffer_fault_user_mappings(struct ion_buffer *buffer)
-{
- return (buffer->flags & ION_FLAG_CACHED) &&
- !(buffer->flags & ION_FLAG_CACHED_NEEDS_SYNC);
-}
-
bool ion_buffer_cached(struct ion_buffer *buffer)
{
return !!(buffer->flags & ION_FLAG_CACHED);
}

-static inline struct page *ion_buffer_page(struct page *page)
-{
- return (struct page *)((unsigned long)page & ~(1UL));
-}
-
-static inline bool ion_buffer_page_is_dirty(struct page *page)
-{
- return !!((unsigned long)page & 1UL);
-}
-
-static inline void ion_buffer_page_dirty(struct page **page)
-{
- *page = (struct page *)((unsigned long)(*page) | 1UL);
-}
-
-static inline void ion_buffer_page_clean(struct page **page)
-{
- *page = (struct page *)((unsigned long)(*page) & ~(1UL));
-}
-
/* this function should only be called while dev->lock is held */
static void ion_buffer_add(struct ion_device *dev,
struct ion_buffer *buffer)
@@ -139,25 +113,6 @@ static struct ion_buffer *ion_buffer_create(struct ion_heap *heap,
buffer->dev = dev;
buffer->size = len;

- if (ion_buffer_fault_user_mappings(buffer)) {
- int num_pages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;
- struct scatterlist *sg;
- int i, j, k = 0;
-
- buffer->pages = vmalloc(sizeof(struct page *) * num_pages);
- if (!buffer->pages) {
- ret = -ENOMEM;
- goto err1;
- }
-
- for_each_sg(table->sgl, sg, table->nents, i) {
- struct page *page = sg_page(sg);
-
- for (j = 0; j < sg->length / PAGE_SIZE; j++)
- buffer->pages[k++] = page++;
- }
- }
-
buffer->dev = dev;
buffer->size = len;
INIT_LIST_HEAD(&buffer->vmas);
@@ -876,69 +831,6 @@ void ion_pages_sync_for_device(struct device *dev, struct page *page,
dma_sync_sg_for_device(dev, &sg, 1, dir);
}

-struct ion_vma_list {
- struct list_head list;
- struct vm_area_struct *vma;
-};
-
-static int ion_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
-{
- struct ion_buffer *buffer = vma->vm_private_data;
- unsigned long pfn;
- int ret;
-
- mutex_lock(&buffer->lock);
- ion_buffer_page_dirty(buffer->pages + vmf->pgoff);
- BUG_ON(!buffer->pages || !buffer->pages[vmf->pgoff]);
-
- pfn = page_to_pfn(ion_buffer_page(buffer->pages[vmf->pgoff]));
- ret = vm_insert_pfn(vma, vmf->address, pfn);
- mutex_unlock(&buffer->lock);
- if (ret)
- return VM_FAULT_ERROR;
-
- return VM_FAULT_NOPAGE;
-}
-
-static void ion_vm_open(struct vm_area_struct *vma)
-{
- struct ion_buffer *buffer = vma->vm_private_data;
- struct ion_vma_list *vma_list;
-
- vma_list = kmalloc(sizeof(*vma_list), GFP_KERNEL);
- if (!vma_list)
- return;
- vma_list->vma = vma;
- mutex_lock(&buffer->lock);
- list_add(&vma_list->list, &buffer->vmas);
- mutex_unlock(&buffer->lock);
- pr_debug("%s: adding %p\n", __func__, vma);
-}
-
-static void ion_vm_close(struct vm_area_struct *vma)
-{
- struct ion_buffer *buffer = vma->vm_private_data;
- struct ion_vma_list *vma_list, *tmp;
-
- pr_debug("%s\n", __func__);
- mutex_lock(&buffer->lock);
- list_for_each_entry_safe(vma_list, tmp, &buffer->vmas, list) {
- if (vma_list->vma != vma)
- continue;
- list_del(&vma_list->list);
- kfree(vma_list);
- pr_debug("%s: deleting %p\n", __func__, vma);
- break;
- }
- mutex_unlock(&buffer->lock);
-}
-
-static const struct vm_operations_struct ion_vma_ops = {
- .open = ion_vm_open,
- .close = ion_vm_close,
- .fault = ion_vm_fault,
-};
-
static int ion_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
{
struct ion_buffer *buffer = dmabuf->priv;
@@ -950,15 +842,6 @@ static int ion_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
return -EINVAL;
}

- if (ion_buffer_fault_user_mappings(buffer)) {
- vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND |
- VM_DONTDUMP;
- vma->vm_private_data = buffer;
- vma->vm_ops = &ion_vma_ops;
- ion_vm_open(vma);
- return 0;
- }
-
if (!(buffer->flags & ION_FLAG_CACHED))
vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);

--
2.7.4