-----Original Message----- From: dri-devel dri-devel-bounces@lists.freedesktop.org On Behalf Of Marek Szyprowski Sent: Tuesday, May 12, 2020 5:01 AM To: dri-devel@lists.freedesktop.org; iommu@lists.linux-foundation.org; linaro-mm-sig@lists.linaro.org; linux-kernel@vger.kernel.org Cc: Pawel Osciak pawel@osciak.com; Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com; David Airlie airlied@linux.ie; linux- media@vger.kernel.org; Hans Verkuil hverkuil-cisco@xs4all.nl; Mauro Carvalho Chehab mchehab@kernel.org; Robin Murphy robin.murphy@arm.com; Christoph Hellwig hch@lst.de; linux-arm- kernel@lists.infradead.org; Marek Szyprowski m.szyprowski@samsung.com Subject: [PATCH v4 38/38] videobuf2: use sgtable-based scatterlist wrappers
Use recently introduced common wrappers operating directly on the struct sg_table objects and scatterlist page iterators to make the code a bit more compact, robust, easier to follow and copy/paste safe.
No functional change, because the code already properly did all the scaterlist related calls.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com
For more information, see '[PATCH v4 00/38] DRM: fix struct sg_table nents vs. orig_nents misuse' thread: https://lore.kernel.org/dri-devel/20200512085710.14688-1- m.szyprowski@samsung.com/T/
.../media/common/videobuf2/videobuf2-dma-contig.c | 41 ++++++++++----
drivers/media/common/videobuf2/videobuf2-dma-sg.c | 32 +++++++--------
drivers/media/common/videobuf2/videobuf2-vmalloc.c | 12 +++---- 3 files changed, 34 insertions(+), 51 deletions(-)
diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c index d3a3ee5..bf31a9d 100644 --- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c @@ -48,16 +48,15 @@ struct vb2_dc_buf {
static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt) {
- struct scatterlist *s; dma_addr_t expected = sg_dma_address(sgt->sgl);
- unsigned int i;
- struct sg_dma_page_iter dma_iter; unsigned long size = 0;
- for_each_sg(sgt->sgl, s, sgt->nents, i) {
if (sg_dma_address(s) != expected)
- for_each_sgtable_dma_page(sgt, &dma_iter, 0) {
if (sg_page_iter_dma_address(&dma_iter) != expected) break;
expected = sg_dma_address(s) + sg_dma_len(s);size += sg_dma_len(s);
expected += PAGE_SIZE;size += PAGE_SIZE;
This code in drm_prime_t_contiguous_size and here. I seem to remember seeing the same pattern in other drivers.
Would it worthwhile to make this a helper as well?
Also, isn't the sg_dma_len() the actual length of the chunk we are looking at?
If its I not PAGE_SIZE (ie. dma chunk is 4 * PAGE_SIZE?), does your loop/calculation still work?
Thanks,
Mike
} return size; } @@ -99,8 +98,7 @@ static void vb2_dc_prepare(void *buf_priv) if (!sgt || buf->db_attach) return;
- dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir);
- dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir);
}
static void vb2_dc_finish(void *buf_priv) @@ -112,7 +110,7 @@ static void vb2_dc_finish(void *buf_priv) if (!sgt || buf->db_attach) return;
- dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->orig_nents, buf-
dma_dir);
- dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir);
}
/*********************************************/ @@ -273,8 +271,8 @@ static void vb2_dc_dmabuf_ops_detach(struct dma_buf *dbuf, * memory locations do not require any explicit cache * maintenance prior or after being used by the device. */
dma_unmap_sg_attrs(db_attach->dev, sgt->sgl, sgt-orig_nents,
attach->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);
dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);@@ -299,8 +297,8 @@ static struct sg_table *vb2_dc_dmabuf_ops_map(
/* release any previous cache */ if (attach->dma_dir != DMA_NONE) {
dma_unmap_sg_attrs(db_attach->dev, sgt->sgl, sgt-orig_nents,
attach->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);
dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);@@ -308,9 +306,8 @@ static struct sg_table *vb2_dc_dmabuf_ops_map( * mapping to the client with new direction, no cache sync * required see comment in vb2_dc_dmabuf_ops_detach() */
- sgt->nents = dma_map_sg_attrs(db_attach->dev, sgt->sgl, sgt-
orig_nents,
dma_dir, DMA_ATTR_SKIP_CPU_SYNC);- if (!sgt->nents) {
- if (dma_map_sgtable(db_attach->dev, sgt, dma_dir,
DMA_ATTR_SKIP_CPU_SYNC)) {@@ -423,8 +420,8 @@ static void vb2_dc_put_userptr(void *buf_priv) * No need to sync to CPU, it's already synced to the CPU * since the finish() memop will have been called before this. */
dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,buf->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);
dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);@@ -521,9 +518,8 @@ static void *vb2_dc_get_userptr(struct device *dev, unsigned long vaddr, * No need to sync to the device, this will happen later when the * prepare() memop is called. */
- sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);
- if (sgt->nents <= 0) {
- if (dma_map_sgtable(buf->dev, sgt, buf->dma_dir,
DMA_ATTR_SKIP_CPU_SYNC)) {@@ -545,8 +541,7 @@ static void *vb2_dc_get_userptr(struct device *dev, unsigned long vaddr, return buf;
fail_map_sg:
- dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
- dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,
DMA_ATTR_SKIP_CPU_SYNC);
fail_sgt_init: sg_free_table(sgt); diff --git a/drivers/media/common/videobuf2/videobuf2-dma-sg.c b/drivers/media/common/videobuf2/videobuf2-dma-sg.c index 92072a0..6ddf953 100644 --- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c +++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c @@ -142,9 +142,8 @@ static void *vb2_dma_sg_alloc(struct device *dev, unsigned long dma_attrs, * No need to sync to the device, this will happen later when the * prepare() memop is called. */
- sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);
- if (!sgt->nents)
if (dma_map_sgtable(buf->dev, sgt, buf->dma_dir,
DMA_ATTR_SKIP_CPU_SYNC)) {goto fail_map;
buf->handler.refcount = &buf->refcount;
@@ -180,8 +179,8 @@ static void vb2_dma_sg_put(void *buf_priv) if (refcount_dec_and_test(&buf->refcount)) { dprintk(1, "%s: Freeing buffer of %d pages\n", __func__, buf->num_pages);
dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,buf->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);
dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);@@ -202,8 +201,7 @@ static void vb2_dma_sg_prepare(void *buf_priv) if (buf->db_attach) return;
- dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir);
- dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir);
}
static void vb2_dma_sg_finish(void *buf_priv) @@ -215,7 +213,7 @@ static void vb2_dma_sg_finish(void *buf_priv) if (buf->db_attach) return;
- dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->orig_nents, buf-
dma_dir);
- dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir);
}
static void *vb2_dma_sg_get_userptr(struct device *dev, unsigned long vaddr, @@ -258,9 +256,8 @@ static void *vb2_dma_sg_get_userptr(struct device *dev, unsigned long vaddr, * No need to sync to the device, this will happen later when the * prepare() memop is called. */
- sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
buf->dma_dir,DMA_ATTR_SKIP_CPU_SYNC);
- if (!sgt->nents)
if (dma_map_sgtable(buf->dev, sgt, buf->dma_dir,
DMA_ATTR_SKIP_CPU_SYNC)) {goto userptr_fail_map;
return buf;
@@ -286,8 +283,7 @@ static void vb2_dma_sg_put_userptr(void *buf_priv)
dprintk(1, "%s: Releasing userspace buffer of %d pages\n", __func__, buf->num_pages);
- dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents, buf-
dma_dir,
DMA_ATTR_SKIP_CPU_SYNC);
- dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,
DMA_ATTR_SKIP_CPU_SYNC); if (buf->vaddr) vm_unmap_ram(buf->vaddr, buf->num_pages); sg_free_table(buf->dma_sgt); @@ -410,8 +406,7 @@ static void vb2_dma_sg_dmabuf_ops_detach(struct dma_buf *dbuf,
/* release the scatterlist cache */ if (attach->dma_dir != DMA_NONE)
dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,attach->dma_dir);
dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir);@@ -436,15 +431,12 @@ static struct sg_table *vb2_dma_sg_dmabuf_ops_map(
/* release any previous cache */ if (attach->dma_dir != DMA_NONE) {
dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,attach->dma_dir);
dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir);attach->dma_dir = DMA_NONE; }
/* mapping to the client with new direction */
- sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
dma_dir);- if (!sgt->nents) {
- if (dma_map_sgtable(db_attach->dev, sgt, dma_dir, 0)) { pr_err("failed to map scatterlist\n"); mutex_unlock(lock); return ERR_PTR(-EIO);
diff --git a/drivers/media/common/videobuf2/videobuf2-vmalloc.c b/drivers/media/common/videobuf2/videobuf2-vmalloc.c index c66fda4..bf5ac63 100644 --- a/drivers/media/common/videobuf2/videobuf2-vmalloc.c +++ b/drivers/media/common/videobuf2/videobuf2-vmalloc.c @@ -229,7 +229,7 @@ static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf *dbuf, kfree(attach); return ret; }
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
for_each_sgtable_sg(sgt, sg, i) { struct page *page = vmalloc_to_page(vaddr);
if (!page) {
@@ -259,8 +259,7 @@ static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf,
/* release the scatterlist cache */ if (attach->dma_dir != DMA_NONE)
dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,attach->dma_dir);
dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir,0); sg_free_table(sgt); kfree(attach); db_attach->priv = NULL; @@ -285,15 +284,12 @@ static struct sg_table *vb2_vmalloc_dmabuf_ops_map(
/* release any previous cache */ if (attach->dma_dir != DMA_NONE) {
dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,attach->dma_dir);
dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir,0); attach->dma_dir = DMA_NONE; }
/* mapping to the client with new direction */
- sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
dma_dir);- if (!sgt->nents) {
- if (dma_map_sgtable(db_attach->dev, sgt, dma_dir, 0)) { pr_err("failed to map scatterlist\n"); mutex_unlock(lock); return ERR_PTR(-EIO);
-- 1.9.1
dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel