Signed-off-by: Jan Kara <jack at suse.cz>
---
 drivers/media/v4l2-core/videobuf2-dma-sg.c | 97 +++++-------------------------
 1 file changed, 15 insertions(+), 82 deletions(-)

diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c 
b/drivers/media/v4l2-core/videobuf2-dma-sg.c
index 71510e4f7d7c..cc82c30d02cf 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
@@ -38,6 +38,7 @@ struct vb2_dma_sg_buf {
        struct device                   *dev;
        void                            *vaddr;
        struct page                     **pages;
+       struct pinned_pfns              *pfns;
        int                             offset;
        enum dma_data_direction         dma_dir;
        struct sg_table                 sg_table;
@@ -51,7 +52,6 @@ struct vb2_dma_sg_buf {
        unsigned int                    num_pages;
        atomic_t                        refcount;
        struct vb2_vmarea_handler       handler;
-       struct vm_area_struct           *vma;

        struct dma_buf_attachment       *db_attach;
 };
@@ -224,25 +224,17 @@ static void vb2_dma_sg_finish(void *buf_priv)
        dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
 }

-static inline int vma_is_io(struct vm_area_struct *vma)
-{
-       return !!(vma->vm_flags & (VM_IO | VM_PFNMAP));
-}
-
 static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
                                    unsigned long size,
                                    enum dma_data_direction dma_dir)
 {
        struct vb2_dma_sg_conf *conf = alloc_ctx;
        struct vb2_dma_sg_buf *buf;
-       unsigned long first, last;
-       int num_pages_from_user;
-       struct vm_area_struct *vma;
        struct sg_table *sgt;
        DEFINE_DMA_ATTRS(attrs);
+       struct pinned_pfns *pfns;

        dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
-
        buf = kzalloc(sizeof *buf, GFP_KERNEL);
        if (!buf)
                return NULL;
@@ -253,63 +245,19 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, 
unsigned long vaddr,
        buf->offset = vaddr & ~PAGE_MASK;
        buf->size = size;
        buf->dma_sgt = &buf->sg_table;
+       pfns = vb2_create_pfnvec(vaddr, size, buf->dma_dir == DMA_FROM_DEVICE);
+       if (IS_ERR(pfns))
+               goto userptr_fail_pfnvec;
+       buf->pfns = pfns;

-       first = (vaddr           & PAGE_MASK) >> PAGE_SHIFT;
-       last  = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT;
-       buf->num_pages = last - first + 1;
-
-       buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
-                            GFP_KERNEL);
-       if (!buf->pages)
-               goto userptr_fail_alloc_pages;
-
-       down_read(&current->mm->mmap_sem);
-       vma = find_vma(current->mm, vaddr);
-       if (!vma) {
-               dprintk(1, "no vma for address %lu\n", vaddr);
-               goto userptr_fail_find_vma;
-       }
-
-       if (vma->vm_end < vaddr + size) {
-               dprintk(1, "vma at %lu is too small for %lu bytes\n",
-                       vaddr, size);
-               goto userptr_fail_find_vma;
-       }
-
-       buf->vma = vb2_get_vma(vma);
-       if (!buf->vma) {
-               dprintk(1, "failed to copy vma\n");
-               goto userptr_fail_find_vma;
-       }
-
-       if (vma_is_io(buf->vma)) {
-               for (num_pages_from_user = 0;
-                    num_pages_from_user < buf->num_pages;
-                    ++num_pages_from_user, vaddr += PAGE_SIZE) {
-                       unsigned long pfn;
-
-                       if (follow_pfn(vma, vaddr, &pfn)) {
-                               dprintk(1, "no page for address %lu\n", vaddr);
-                               break;
-                       }
-                       buf->pages[num_pages_from_user] = pfn_to_page(pfn);
-               }
-       } else
-               num_pages_from_user = get_user_pages(current, current->mm,
-                                            vaddr & PAGE_MASK,
-                                            buf->num_pages,
-                                            buf->dma_dir == DMA_FROM_DEVICE,
-                                            1, /* force */
-                                            buf->pages,
-                                            NULL);
-       up_read(&current->mm->mmap_sem);
-
-       if (num_pages_from_user != buf->num_pages)
-               goto userptr_fail_get_user_pages;
+       if (pfns_vector_to_pages(pfns))
+               goto userptr_fail_sgtable;
+       buf->pages = pfns_vector_pages(pfns);
+       buf->num_pages = pfns_vector_count(pfns);

        if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
                        buf->num_pages, buf->offset, size, 0))
-               goto userptr_fail_alloc_table_from_pages;
+               goto userptr_fail_sgtable;

        sgt = &buf->sg_table;
        /*
@@ -323,19 +271,9 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, 
unsigned long vaddr,

 userptr_fail_map:
        sg_free_table(&buf->sg_table);
-userptr_fail_alloc_table_from_pages:
-userptr_fail_get_user_pages:
-       dprintk(1, "get_user_pages requested/got: %d/%d]\n",
-               buf->num_pages, num_pages_from_user);
-       if (!vma_is_io(buf->vma))
-               while (--num_pages_from_user >= 0)
-                       put_page(buf->pages[num_pages_from_user]);
-       down_read(&current->mm->mmap_sem);
-       vb2_put_vma(buf->vma);
-userptr_fail_find_vma:
-       up_read(&current->mm->mmap_sem);
-       kfree(buf->pages);
-userptr_fail_alloc_pages:
+userptr_fail_sgtable:
+       vb2_destroy_pfnvec(pfns);
+userptr_fail_pfnvec:
        kfree(buf);
        return NULL;
 }
@@ -362,13 +300,8 @@ static void vb2_dma_sg_put_userptr(void *buf_priv)
        while (--i >= 0) {
                if (buf->dma_dir == DMA_FROM_DEVICE)
                        set_page_dirty_lock(buf->pages[i]);
-               if (!vma_is_io(buf->vma))
-                       put_page(buf->pages[i]);
        }
-       kfree(buf->pages);
-       down_read(&current->mm->mmap_sem);
-       vb2_put_vma(buf->vma);
-       up_read(&current->mm->mmap_sem);
+       vb2_destroy_pfnvec(buf->pfns);
        kfree(buf);
 }

-- 
2.1.4

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