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
scatterlist related calls.
Signed-off-by: Marek Szyprowski <[email protected]>
Reviewed-by: Robin Murphy <[email protected]>
---
.../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);
--
2.17.1
On Mon, Sep 7, 2020 at 4:02 PM Marek Szyprowski
<[email protected]> wrote:
>
> Hi Tomasz,
>
> On 07.09.2020 15:07, Tomasz Figa wrote:
> > On Fri, Sep 4, 2020 at 3:35 PM Marek Szyprowski
> > <[email protected]> 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
> >> scatterlist related calls.
> >>
> >> Signed-off-by: Marek Szyprowski <[email protected]>
> >> Reviewed-by: Robin Murphy <[email protected]>
> >> ---
> >> .../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(-)
> >>
> > Thanks for the patch! Please see my comments inline.
> >
> >> 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);
> > As opposed to dma_map_sg_attrs(), dma_map_sgtable() now returns an
> > error code on its own. Is it expected to ignore it and return -EIO?
>
> Those errors are more or less propagated to userspace and -EIO has been
> already widely documented in V4L2 documentation as the error code for
> the most of the V4L2 ioctls. I don't want to change it. A possible
> -EINVAL returned from dma_map_sgtable() was just one of the 'generic'
> error codes, not very descriptive in that case. Probably the main
> problem here is that dma_map_sg() and friend doesn't return any error
> codes...
True for the alloc/get_*() callbacks, but the dmabuf_ops_map() ones
are used for the in-kernel DMA-buf exporter ops, called by DMA-buf
importers.
As a side note, returning user-facing error codes from deep internals
of vb2 and having the userspace rely on particular values sounds quite
fragile. For example, I see vb2_dc_attach_dmabuf() returning a return
value coming from dma_buf_attach() directly and __prepare_dmabuf()
propagating it back to __buf_prepare(), which can just return that
back to the userspace. I guess we might have to do some follow-up work
to clean it up.
Best regards,
Tomasz
Hi Tomasz,
On 07.09.2020 15:07, Tomasz Figa wrote:
> On Fri, Sep 4, 2020 at 3:35 PM Marek Szyprowski
> <[email protected]> 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
>> scatterlist related calls.
>>
>> Signed-off-by: Marek Szyprowski <[email protected]>
>> Reviewed-by: Robin Murphy <[email protected]>
>> ---
>> .../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(-)
>>
> Thanks for the patch! Please see my comments inline.
>
>> 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);
> As opposed to dma_map_sg_attrs(), dma_map_sgtable() now returns an
> error code on its own. Is it expected to ignore it and return -EIO?
Those errors are more or less propagated to userspace and -EIO has been
already widely documented in V4L2 documentation as the error code for
the most of the V4L2 ioctls. I don't want to change it. A possible
-EINVAL returned from dma_map_sgtable() was just one of the 'generic'
error codes, not very descriptive in that case. Probably the main
problem here is that dma_map_sg() and friend doesn't return any error
codes...
> ...
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
Hi Marek,
On Fri, Sep 4, 2020 at 3:35 PM Marek Szyprowski
<[email protected]> 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
> scatterlist related calls.
>
> Signed-off-by: Marek Szyprowski <[email protected]>
> Reviewed-by: Robin Murphy <[email protected]>
> ---
> .../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(-)
>
Thanks for the patch! Please see my comments inline.
> 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);
As opposed to dma_map_sg_attrs(), dma_map_sgtable() now returns an
error code on its own. Is it expected to ignore it and return -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;
Ditto.
> 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;
>
Ditto.
> 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;
>
Ditto.
> 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);
Ditto.
> 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);
Ditto.
Best regards,
Tomasz
On 04/09/2020 15:17, 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
> scatterlist related calls.
>
> Signed-off-by: Marek Szyprowski <[email protected]>
> Reviewed-by: Robin Murphy <[email protected]>
Acked-by: Hans Verkuil <[email protected]>
Note that I agree with Marek to keep returning -EIO. If we want to propagate
low-level errors, then that should be done in a separate patch. But I think EIO
is fine.
Regards,
Hans
> ---
> .../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);
>
On Thu, Sep 10, 2020 at 11:17 AM Hans Verkuil <[email protected]> wrote:
>
> On 04/09/2020 15:17, 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
> > scatterlist related calls.
> >
> > Signed-off-by: Marek Szyprowski <[email protected]>
> > Reviewed-by: Robin Murphy <[email protected]>
>
> Acked-by: Hans Verkuil <[email protected]>
>
> Note that I agree with Marek to keep returning -EIO. If we want to propagate
> low-level errors, then that should be done in a separate patch. But I think EIO
> is fine.
As I mentioned, there are 2 different cases here - UAPI and kAPI. I
agree that we should keep -EIO for UAPI, but kAPI is another story.
But if we're convinced that -EIO is also fine for the latter, I'm fine
with that.
Best regards,
Tomasz
>
> Regards,
>
> Hans
>
> > ---
> > .../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);
> >
>