Re: [PATCH v9 32/32] videobuf2: use sgtable-based scatterlist wrappers

From: Robin Murphy
Date: Tue Sep 01 2020 - 16:19:14 EST


On 2020-08-26 07:33, Marek Szyprowski wrote:
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.

^^ typo

Otherwise,

Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>

Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
.../common/videobuf2/videobuf2-dma-contig.c | 34 ++++++++-----------
.../media/common/videobuf2/videobuf2-dma-sg.c | 32 +++++++----------
.../common/videobuf2/videobuf2-vmalloc.c | 12 +++----
3 files changed, 31 insertions(+), 47 deletions(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
index ec3446cc45b8..1b242d844dde 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c
@@ -58,10 +58,10 @@ static unsigned long vb2_dc_get_contiguous_size(struct sg_table *sgt)
unsigned int i;
unsigned long size = 0;
- for_each_sg(sgt->sgl, s, sgt->nents, i) {
+ for_each_sgtable_dma_sg(sgt, s, i) {
if (sg_dma_address(s) != expected)
break;
- expected = sg_dma_address(s) + sg_dma_len(s);
+ expected += sg_dma_len(s);
size += sg_dma_len(s);
}
return size;
@@ -103,8 +103,7 @@ static void vb2_dc_prepare(void *buf_priv)
if (!sgt)
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)
@@ -115,7 +114,7 @@ static void vb2_dc_finish(void *buf_priv)
if (!sgt)
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);
}
/*********************************************/
@@ -275,8 +274,8 @@ 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);
sg_free_table(sgt);
kfree(attach);
db_attach->priv = NULL;
@@ -301,8 +300,8 @@ 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);
attach->dma_dir = DMA_NONE;
}
@@ -310,9 +309,8 @@ 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)) {
pr_err("failed to map scatterlist\n");
mutex_unlock(lock);
return ERR_PTR(-EIO);
@@ -455,8 +453,8 @@ 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);
pages = frame_vector_pages(buf->vec);
/* sgt should exist only if vector contains pages... */
BUG_ON(IS_ERR(pages));
@@ -553,9 +551,8 @@ 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)) {
pr_err("failed to map scatterlist\n");
ret = -EIO;
goto fail_sgt_init;
@@ -577,8 +574,7 @@ 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 0a40e00f0d7e..0dd3b19025e0 100644
--- a/drivers/media/common/videobuf2/videobuf2-dma-sg.c
+++ b/drivers/media/common/videobuf2/videobuf2-dma-sg.c
@@ -148,9 +148,8 @@ 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;
@@ -186,8 +185,8 @@ 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);
if (buf->vaddr)
vm_unmap_ram(buf->vaddr, buf->num_pages);
sg_free_table(buf->dma_sgt);
@@ -204,8 +203,7 @@ static void vb2_dma_sg_prepare(void *buf_priv)
struct vb2_dma_sg_buf *buf = buf_priv;
struct sg_table *sgt = buf->dma_sgt;
- 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)
@@ -213,7 +211,7 @@ static void vb2_dma_sg_finish(void *buf_priv)
struct vb2_dma_sg_buf *buf = buf_priv;
struct sg_table *sgt = buf->dma_sgt;
- 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,
@@ -256,9 +254,8 @@ 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;
@@ -284,8 +281,7 @@ 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);
@@ -408,8 +404,7 @@ 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, 0);
sg_free_table(sgt);
kfree(attach);
db_attach->priv = NULL;
@@ -434,15 +429,12 @@ 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, 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);
diff --git a/drivers/media/common/videobuf2/videobuf2-vmalloc.c b/drivers/media/common/videobuf2/videobuf2-vmalloc.c
index c66fda4a65e4..bf5ac63a5742 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);