Convert vb2_dc_get_userptr() to use passed vector of pfns. When we are doing that there's no need to allocate page array and some code can be simplified.
Signed-off-by: Jan Kara jack@suse.cz --- drivers/media/v4l2-core/videobuf2-dma-contig.c | 213 ++++--------------------- 1 file changed, 32 insertions(+), 181 deletions(-)
diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c index 96eceabb307b..d3cefc5c98bc 100644 --- a/drivers/media/v4l2-core/videobuf2-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c @@ -32,15 +32,13 @@ struct vb2_dc_buf { dma_addr_t dma_addr; enum dma_data_direction dma_dir; struct sg_table *dma_sgt; + struct pinned_pfns *pfns;
/* MMAP related */ struct vb2_vmarea_handler handler; atomic_t refcount; struct sg_table *sgt_base;
- /* USERPTR related */ - struct vm_area_struct *vma; - /* DMABUF related */ struct dma_buf_attachment *db_attach; }; @@ -49,24 +47,6 @@ struct vb2_dc_buf { /* scatterlist table functions */ /*********************************************/
- -static void vb2_dc_sgt_foreach_page(struct sg_table *sgt, - void (*cb)(struct page *pg)) -{ - struct scatterlist *s; - unsigned int i; - - for_each_sg(sgt->sgl, s, sgt->orig_nents, i) { - struct page *page = sg_page(s); - unsigned int n_pages = PAGE_ALIGN(s->offset + s->length) - >> PAGE_SHIFT; - unsigned int j; - - for (j = 0; j < n_pages; ++j, ++page) - cb(page); - } -} - static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt) { struct scatterlist *s; @@ -423,92 +403,12 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags) /* callbacks for USERPTR buffers */ /*********************************************/
-static inline int vma_is_io(struct vm_area_struct *vma) -{ - return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); -} - -static int vb2_dc_get_user_pfn(unsigned long start, int n_pages, - struct vm_area_struct *vma, unsigned long *res) -{ - unsigned long pfn, start_pfn, prev_pfn; - unsigned int i; - int ret; - - if (!vma_is_io(vma)) - return -EFAULT; - - ret = follow_pfn(vma, start, &pfn); - if (ret) - return ret; - - start_pfn = pfn; - start += PAGE_SIZE; - - for (i = 1; i < n_pages; ++i, start += PAGE_SIZE) { - prev_pfn = pfn; - ret = follow_pfn(vma, start, &pfn); - - if (ret) { - pr_err("no page for address %lu\n", start); - return ret; - } - if (pfn != prev_pfn + 1) - return -EINVAL; - } - - *res = start_pfn; - return 0; -} - -static int vb2_dc_get_user_pages(unsigned long start, struct page **pages, - int n_pages, struct vm_area_struct *vma, - enum dma_data_direction dma_dir) -{ - if (vma_is_io(vma)) { - unsigned int i; - - for (i = 0; i < n_pages; ++i, start += PAGE_SIZE) { - unsigned long pfn; - int ret = follow_pfn(vma, start, &pfn); - - if (!pfn_valid(pfn)) - return -EINVAL; - - if (ret) { - pr_err("no page for address %lu\n", start); - return ret; - } - pages[i] = pfn_to_page(pfn); - } - } else { - int n; - - n = get_user_pages(current, current->mm, start & PAGE_MASK, - n_pages, dma_dir == DMA_FROM_DEVICE, 1, pages, NULL); - /* negative error means that no page was pinned */ - n = max(n, 0); - if (n != n_pages) { - pr_err("got only %d of %d user pages\n", n, n_pages); - while (n) - put_page(pages[--n]); - return -EFAULT; - } - } - - return 0; -} - -static void vb2_dc_put_dirty_page(struct page *page) -{ - set_page_dirty_lock(page); - put_page(page); -} - static void vb2_dc_put_userptr(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv; struct sg_table *sgt = buf->dma_sgt; + int i; + struct page **pages;
if (sgt) { DEFINE_DMA_ATTRS(attrs); @@ -520,15 +420,13 @@ static void vb2_dc_put_userptr(void *buf_priv) */ dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir, &attrs); - if (!vma_is_io(buf->vma)) - vb2_dc_sgt_foreach_page(sgt, vb2_dc_put_dirty_page); - + pages = pfns_vector_pages(buf->pfns); + for (i = 0; i < pfns_vector_count(buf->pfns); i++) + set_page_dirty_lock(pages[i]); sg_free_table(sgt); kfree(sgt); } - down_read(¤t->mm->mmap_sem); - vb2_put_vma(buf->vma); - up_read(¤t->mm->mmap_sem); + vb2_destroy_pfnvec(buf->pfns); kfree(buf); }
@@ -568,13 +466,10 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, { struct vb2_dc_conf *conf = alloc_ctx; struct vb2_dc_buf *buf; - unsigned long start; - unsigned long end; + struct pinned_pfns *pfns; unsigned long offset; - struct page **pages; - int n_pages; + int n_pages, i; int ret = 0; - struct vm_area_struct *vma; struct sg_table *sgt; unsigned long contig_size; unsigned long dma_align = dma_get_cache_alignment(); @@ -600,76 +495,43 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, buf->dev = conf->dev; buf->dma_dir = dma_dir;
- start = vaddr & PAGE_MASK; offset = vaddr & ~PAGE_MASK; - end = PAGE_ALIGN(vaddr + size); - n_pages = (end - start) >> PAGE_SHIFT; - - pages = kmalloc(n_pages * sizeof(pages[0]), GFP_KERNEL); - if (!pages) { - ret = -ENOMEM; - pr_err("failed to allocate pages table\n"); + pfns = vb2_create_pfnvec(vaddr, size, dma_dir == DMA_FROM_DEVICE); + if (IS_ERR(pfns)) { + ret = PTR_ERR(pfns); goto fail_buf; } + buf->pfns = pfns; + n_pages = pfns_vector_count(pfns); + ret = pfns_vector_to_pages(pfns); + if (ret < 0) { + unsigned long *nums = pfns_vector_pfns(pfns);
- down_read(¤t->mm->mmap_sem); - /* current->mm->mmap_sem is taken by videobuf2 core */ - vma = find_vma(current->mm, vaddr); - if (!vma) { - pr_err("no vma for address %lu\n", vaddr); - ret = -EFAULT; - goto fail_pages; - } - - if (vma->vm_end < vaddr + size) { - pr_err("vma at %lu is too small for %lu bytes\n", vaddr, size); - ret = -EFAULT; - goto fail_pages; - } - - buf->vma = vb2_get_vma(vma); - if (!buf->vma) { - pr_err("failed to copy vma\n"); - ret = -ENOMEM; - goto fail_pages; - } - - /* extract page list from userspace mapping */ - ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, - dma_dir == DMA_FROM_DEVICE); - if (ret) { - unsigned long pfn; - if (vb2_dc_get_user_pfn(start, n_pages, vma, &pfn) == 0) { - up_read(¤t->mm->mmap_sem); - buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, pfn); - buf->size = size; - kfree(pages); - return buf; - } - - pr_err("failed to get user pages\n"); - goto fail_vma; + /* + * Failed to convert to pages... Check the memory is physically + * contiguous and use direct mapping + */ + for (i = 1; i < n_pages; i++) + if (nums[i-1] + 1 != nums[i]) + goto fail_pfnvec; + buf->dma_addr = vb2_dc_pfn_to_dma(buf->dev, nums[0]); + goto out; } - up_read(¤t->mm->mmap_sem);
sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) { pr_err("failed to allocate sg table\n"); ret = -ENOMEM; - goto fail_get_user_pages; + goto fail_pfnvec; }
- ret = sg_alloc_table_from_pages(sgt, pages, n_pages, + ret = sg_alloc_table_from_pages(sgt, pfns_vector_pages(pfns), n_pages, offset, size, GFP_KERNEL); if (ret) { pr_err("failed to initialize sg table\n"); goto fail_sgt; }
- /* pages are no longer needed */ - kfree(pages); - pages = NULL; - /* * No need to sync to the device, this will happen later when the * prepare() memop is called. @@ -691,8 +553,9 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr, }
buf->dma_addr = sg_dma_address(sgt->sgl); - buf->size = size; buf->dma_sgt = sgt; +out: + buf->size = size;
return buf;
@@ -701,25 +564,13 @@ fail_map_sg: buf->dma_dir, &attrs);
fail_sgt_init: - if (!vma_is_io(buf->vma)) - vb2_dc_sgt_foreach_page(sgt, put_page); sg_free_table(sgt);
fail_sgt: kfree(sgt);
-fail_get_user_pages: - if (pages && !vma_is_io(buf->vma)) - while (n_pages) - put_page(pages[--n_pages]); - - down_read(¤t->mm->mmap_sem); -fail_vma: - vb2_put_vma(buf->vma); - -fail_pages: - up_read(¤t->mm->mmap_sem); - kfree(pages); /* kfree is NULL-proof */ +fail_pfnvec: + vb2_destroy_pfnvec(pfns);
fail_buf: kfree(buf);