* [PATCH v5 23/38] drm: tegra: fix common struct sg_table related issues
[not found] ` <20200513133245.6408-1-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
@ 2020-05-13 13:32 ` Marek Szyprowski
2020-05-13 13:32 ` [PATCH v5 28/38] drm: host1x: " Marek Szyprowski
2020-05-13 13:32 ` [PATCH v5 33/38] staging: tegra-vde: " Marek Szyprowski
2 siblings, 0 replies; 4+ messages in thread
From: Marek Szyprowski @ 2020-05-13 13:32 UTC (permalink / raw)
To: dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW,
iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA,
linaro-mm-sig-cunTk1MwBs8s++Sfvej+rw,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: Bartlomiej Zolnierkiewicz, David Airlie, Jonathan Hunter,
Thierry Reding, Daniel Vetter,
linux-tegra-u79uwXL29TY76Z2rM5mHXA, Robin Murphy,
Christoph Hellwig,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
returns the number of the created entries in the DMA address space.
However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and
dma_unmap_sg must be called with the original number of the entries
passed to the dma_map_sg().
struct sg_table is a common structure used for describing a non-contiguous
memory buffer, used commonly in the DRM and graphics subsystems. It
consists of a scatterlist with memory pages and DMA addresses (sgl entry),
as well as the number of scatterlist entries: CPU pages (orig_nents entry)
and DMA mapped pages (nents entry).
It turned out that it was a common mistake to misuse nents and orig_nents
entries, calling DMA-mapping functions with a wrong number of entries or
ignoring the number of mapped entries returned by the dma_map_sg()
function.
To avoid such issues, lets use a common dma-mapping wrappers operating
directly on the struct sg_table objects and use scatterlist page
iterators where possible. This, almost always, hides references to the
nents and orig_nents entries, making the code robust, easier to follow
and copy/paste safe.
Signed-off-by: Marek Szyprowski <m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
---
For more information, see '[PATCH v5 00/38] DRM: fix struct sg_table nents
vs. orig_nents misuse' thread:
https://lore.kernel.org/linux-iommu/20200513132114.6046-1-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org/T/
---
drivers/gpu/drm/tegra/gem.c | 27 ++++++++++-----------------
drivers/gpu/drm/tegra/plane.c | 15 +++++----------
2 files changed, 15 insertions(+), 27 deletions(-)
diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index 6237681..2169130 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -98,8 +98,8 @@ static struct sg_table *tegra_bo_pin(struct device *dev, struct host1x_bo *bo,
* the SG table needs to be copied to avoid overwriting any
* other potential users of the original SG table.
*/
- err = sg_alloc_table_from_sg(sgt, obj->sgt->sgl, obj->sgt->nents,
- GFP_KERNEL);
+ err = sg_alloc_table_from_sg(sgt, obj->sgt->sgl,
+ obj->sgt->orig_nents, GFP_KERNEL);
if (err < 0)
goto free;
} else {
@@ -196,8 +196,7 @@ static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
bo->iova = bo->mm->start;
- bo->size = iommu_map_sg(tegra->domain, bo->iova, bo->sgt->sgl,
- bo->sgt->nents, prot);
+ bo->size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
if (!bo->size) {
dev_err(tegra->drm->dev, "failed to map buffer\n");
err = -ENOMEM;
@@ -264,8 +263,7 @@ static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm,
static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo)
{
if (bo->pages) {
- dma_unmap_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents,
- DMA_FROM_DEVICE);
+ dma_unmap_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
drm_gem_put_pages(&bo->gem, bo->pages, true, true);
sg_free_table(bo->sgt);
kfree(bo->sgt);
@@ -290,12 +288,9 @@ static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)
goto put_pages;
}
- err = dma_map_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents,
- DMA_FROM_DEVICE);
- if (err == 0) {
- err = -EFAULT;
+ err = dma_map_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
+ if (err)
goto free_sgt;
- }
return 0;
@@ -571,7 +566,7 @@ int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
goto free;
}
- if (dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir) == 0)
+ if (dma_map_sgtable(attach->dev, sgt, dir, 0))
goto free;
return sgt;
@@ -590,7 +585,7 @@ static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
struct tegra_bo *bo = to_tegra_bo(gem);
if (bo->pages)
- dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir);
+ dma_unmap_sgtable(attach->dev, sgt, dir, 0);
sg_free_table(sgt);
kfree(sgt);
@@ -609,8 +604,7 @@ static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf,
struct drm_device *drm = gem->dev;
if (bo->pages)
- dma_sync_sg_for_cpu(drm->dev, bo->sgt->sgl, bo->sgt->nents,
- DMA_FROM_DEVICE);
+ dma_sync_sgtable_for_cpu(drm->dev, bo->sgt, DMA_FROM_DEVICE);
return 0;
}
@@ -623,8 +617,7 @@ static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf,
struct drm_device *drm = gem->dev;
if (bo->pages)
- dma_sync_sg_for_device(drm->dev, bo->sgt->sgl, bo->sgt->nents,
- DMA_TO_DEVICE);
+ dma_sync_sgtable_for_device(drm->dev, bo->sgt, DMA_TO_DEVICE);
return 0;
}
diff --git a/drivers/gpu/drm/tegra/plane.c b/drivers/gpu/drm/tegra/plane.c
index 9ccfb56..0d2ef16 100644
--- a/drivers/gpu/drm/tegra/plane.c
+++ b/drivers/gpu/drm/tegra/plane.c
@@ -130,12 +130,9 @@ static int tegra_dc_pin(struct tegra_dc *dc, struct tegra_plane_state *state)
}
if (sgt) {
- err = dma_map_sg(dc->dev, sgt->sgl, sgt->nents,
- DMA_TO_DEVICE);
- if (err == 0) {
- err = -ENOMEM;
+ err = dma_map_sgtable(dc->dev, sgt, DMA_TO_DEVICE, 0);
+ if (err)
goto unpin;
- }
/*
* The display controller needs contiguous memory, so
@@ -143,7 +140,7 @@ static int tegra_dc_pin(struct tegra_dc *dc, struct tegra_plane_state *state)
* map its SG table to a single contiguous chunk of
* I/O virtual memory.
*/
- if (err > 1) {
+ if (sgt->nents > 1) {
err = -EINVAL;
goto unpin;
}
@@ -165,8 +162,7 @@ static int tegra_dc_pin(struct tegra_dc *dc, struct tegra_plane_state *state)
struct sg_table *sgt = state->sgt[i];
if (sgt)
- dma_unmap_sg(dc->dev, sgt->sgl, sgt->nents,
- DMA_TO_DEVICE);
+ dma_unmap_sgtable(dc->dev, sgt, DMA_TO_DEVICE, 0);
host1x_bo_unpin(dc->dev, &bo->base, sgt);
state->iova[i] = DMA_MAPPING_ERROR;
@@ -185,8 +181,7 @@ static void tegra_dc_unpin(struct tegra_dc *dc, struct tegra_plane_state *state)
struct sg_table *sgt = state->sgt[i];
if (sgt)
- dma_unmap_sg(dc->dev, sgt->sgl, sgt->nents,
- DMA_TO_DEVICE);
+ dma_unmap_sgtable(dc->dev, sgt, DMA_TO_DEVICE, 0);
host1x_bo_unpin(dc->dev, &bo->base, sgt);
state->iova[i] = DMA_MAPPING_ERROR;
--
1.9.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v5 28/38] drm: host1x: fix common struct sg_table related issues
[not found] ` <20200513133245.6408-1-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
2020-05-13 13:32 ` [PATCH v5 23/38] drm: tegra: fix common struct sg_table related issues Marek Szyprowski
@ 2020-05-13 13:32 ` Marek Szyprowski
2020-05-13 13:32 ` [PATCH v5 33/38] staging: tegra-vde: " Marek Szyprowski
2 siblings, 0 replies; 4+ messages in thread
From: Marek Szyprowski @ 2020-05-13 13:32 UTC (permalink / raw)
To: dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW,
iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA,
linaro-mm-sig-cunTk1MwBs8s++Sfvej+rw,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: Bartlomiej Zolnierkiewicz, David Airlie, Thierry Reding,
Daniel Vetter, linux-tegra-u79uwXL29TY76Z2rM5mHXA, Robin Murphy,
Christoph Hellwig,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
returns the number of the created entries in the DMA address space.
However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and
dma_unmap_sg must be called with the original number of the entries
passed to the dma_map_sg().
struct sg_table is a common structure used for describing a non-contiguous
memory buffer, used commonly in the DRM and graphics subsystems. It
consists of a scatterlist with memory pages and DMA addresses (sgl entry),
as well as the number of scatterlist entries: CPU pages (orig_nents entry)
and DMA mapped pages (nents entry).
It turned out that it was a common mistake to misuse nents and orig_nents
entries, calling DMA-mapping functions with a wrong number of entries or
ignoring the number of mapped entries returned by the dma_map_sg()
function.
To avoid such issues, lets use a common dma-mapping wrappers operating
directly on the struct sg_table objects and use scatterlist page
iterators where possible. This, almost always, hides references to the
nents and orig_nents entries, making the code robust, easier to follow
and copy/paste safe.
Signed-off-by: Marek Szyprowski <m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
---
For more information, see '[PATCH v5 00/38] DRM: fix struct sg_table nents
vs. orig_nents misuse' thread:
https://lore.kernel.org/linux-iommu/20200513132114.6046-1-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org/T/
---
drivers/gpu/host1x/job.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c
index a10643a..4832b57 100644
--- a/drivers/gpu/host1x/job.c
+++ b/drivers/gpu/host1x/job.c
@@ -166,11 +166,9 @@ static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
goto unpin;
}
- err = dma_map_sg(dev, sgt->sgl, sgt->nents, dir);
- if (!err) {
- err = -ENOMEM;
+ err = dma_map_sgtable(dev, sgt, dir, 0);
+ if (err)
goto unpin;
- }
job->unpins[job->num_unpins].dev = dev;
job->unpins[job->num_unpins].dir = dir;
@@ -217,7 +215,7 @@ static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
}
if (!IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL) && host->domain) {
- for_each_sg(sgt->sgl, sg, sgt->nents, j)
+ for_each_sgtable_sg(sgt, sg, j)
gather_size += sg->length;
gather_size = iova_align(&host->iova, gather_size);
@@ -229,9 +227,9 @@ static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
goto unpin;
}
- err = iommu_map_sg(host->domain,
+ err = iommu_map_sgtable(host->domain,
iova_dma_addr(&host->iova, alloc),
- sgt->sgl, sgt->nents, IOMMU_READ);
+ sgt, IOMMU_READ);
if (err == 0) {
__free_iova(&host->iova, alloc);
err = -EINVAL;
@@ -241,12 +239,9 @@ static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
job->unpins[job->num_unpins].size = gather_size;
phys_addr = iova_dma_addr(&host->iova, alloc);
} else if (sgt) {
- err = dma_map_sg(host->dev, sgt->sgl, sgt->nents,
- DMA_TO_DEVICE);
- if (!err) {
- err = -ENOMEM;
+ err = dma_map_sgtable(host->dev, sgt, DMA_TO_DEVICE, 0);
+ if (err)
goto unpin;
- }
job->unpins[job->num_unpins].dir = DMA_TO_DEVICE;
job->unpins[job->num_unpins].dev = host->dev;
@@ -647,8 +642,7 @@ void host1x_job_unpin(struct host1x_job *job)
}
if (unpin->dev && sgt)
- dma_unmap_sg(unpin->dev, sgt->sgl, sgt->nents,
- unpin->dir);
+ dma_unmap_sgtable(unpin->dev, sgt, unpin->dir, 0);
host1x_bo_unpin(dev, unpin->bo, sgt);
host1x_bo_put(unpin->bo);
--
1.9.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v5 33/38] staging: tegra-vde: fix common struct sg_table related issues
[not found] ` <20200513133245.6408-1-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
2020-05-13 13:32 ` [PATCH v5 23/38] drm: tegra: fix common struct sg_table related issues Marek Szyprowski
2020-05-13 13:32 ` [PATCH v5 28/38] drm: host1x: " Marek Szyprowski
@ 2020-05-13 13:32 ` Marek Szyprowski
[not found] ` <20200513133245.6408-33-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
2 siblings, 1 reply; 4+ messages in thread
From: Marek Szyprowski @ 2020-05-13 13:32 UTC (permalink / raw)
To: dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW,
iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA,
linaro-mm-sig-cunTk1MwBs8s++Sfvej+rw,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: Marek Szyprowski, Christoph Hellwig, Robin Murphy,
Bartlomiej Zolnierkiewicz,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, David Airlie,
Daniel Vetter, Dmitry Osipenko, Mauro Carvalho Chehab,
Greg Kroah-Hartman, Thierry Reding, Jonathan Hunter,
linux-media-u79uwXL29TY76Z2rM5mHXA,
linux-tegra-u79uwXL29TY76Z2rM5mHXA,
devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b
The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
returns the number of the created entries in the DMA address space.
However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and
dma_unmap_sg must be called with the original number of the entries
passed to the dma_map_sg().
struct sg_table is a common structure used for describing a non-contiguous
memory buffer, used commonly in the DRM and graphics subsystems. It
consists of a scatterlist with memory pages and DMA addresses (sgl entry),
as well as the number of scatterlist entries: CPU pages (orig_nents entry)
and DMA mapped pages (nents entry).
It turned out that it was a common mistake to misuse nents and orig_nents
entries, calling DMA-mapping functions with a wrong number of entries or
ignoring the number of mapped entries returned by the dma_map_sg()
function.
To avoid such issues, lets use a common dma-mapping wrappers operating
directly on the struct sg_table objects and use scatterlist page
iterators where possible. This, almost always, hides references to the
nents and orig_nents entries, making the code robust, easier to follow
and copy/paste safe.
Signed-off-by: Marek Szyprowski <m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
---
For more information, see '[PATCH v5 00/38] DRM: fix struct sg_table nents
vs. orig_nents misuse' thread:
https://lore.kernel.org/linux-iommu/20200513132114.6046-1-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org/T/
---
drivers/staging/media/tegra-vde/iommu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/media/tegra-vde/iommu.c b/drivers/staging/media/tegra-vde/iommu.c
index 6af863d..adf8dc7 100644
--- a/drivers/staging/media/tegra-vde/iommu.c
+++ b/drivers/staging/media/tegra-vde/iommu.c
@@ -36,8 +36,8 @@ int tegra_vde_iommu_map(struct tegra_vde *vde,
addr = iova_dma_addr(&vde->iova, iova);
- size = iommu_map_sg(vde->domain, addr, sgt->sgl, sgt->nents,
- IOMMU_READ | IOMMU_WRITE);
+ size = iommu_map_sgtable(vde->domain, addr, sgt,
+ IOMMU_READ | IOMMU_WRITE);
if (!size) {
__free_iova(&vde->iova, iova);
return -ENXIO;
--
1.9.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v5 33/38] staging: tegra-vde: fix common struct sg_table related issues
[not found] ` <20200513133245.6408-33-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
@ 2020-05-14 20:07 ` Dmitry Osipenko
0 siblings, 0 replies; 4+ messages in thread
From: Dmitry Osipenko @ 2020-05-14 20:07 UTC (permalink / raw)
To: Marek Szyprowski, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW,
iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA,
linaro-mm-sig-cunTk1MwBs8s++Sfvej+rw,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: Christoph Hellwig, Robin Murphy, Bartlomiej Zolnierkiewicz,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, David Airlie,
Daniel Vetter, Mauro Carvalho Chehab, Greg Kroah-Hartman,
Thierry Reding, Jonathan Hunter,
linux-media-u79uwXL29TY76Z2rM5mHXA,
linux-tegra-u79uwXL29TY76Z2rM5mHXA,
devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b
13.05.2020 16:32, Marek Szyprowski пишет:
> The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
> returns the number of the created entries in the DMA address space.
> However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and
> dma_unmap_sg must be called with the original number of the entries
> passed to the dma_map_sg().
>
> struct sg_table is a common structure used for describing a non-contiguous
> memory buffer, used commonly in the DRM and graphics subsystems. It
> consists of a scatterlist with memory pages and DMA addresses (sgl entry),
> as well as the number of scatterlist entries: CPU pages (orig_nents entry)
> and DMA mapped pages (nents entry).
>
> It turned out that it was a common mistake to misuse nents and orig_nents
> entries, calling DMA-mapping functions with a wrong number of entries or
> ignoring the number of mapped entries returned by the dma_map_sg()
> function.
>
> To avoid such issues, lets use a common dma-mapping wrappers operating
> directly on the struct sg_table objects and use scatterlist page
> iterators where possible. This, almost always, hides references to the
> nents and orig_nents entries, making the code robust, easier to follow
> and copy/paste safe.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> ---
> For more information, see '[PATCH v5 00/38] DRM: fix struct sg_table nents
> vs. orig_nents misuse' thread:
> https://lore.kernel.org/linux-iommu/20200513132114.6046-1-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org/T/
> ---
> drivers/staging/media/tegra-vde/iommu.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/media/tegra-vde/iommu.c b/drivers/staging/media/tegra-vde/iommu.c
> index 6af863d..adf8dc7 100644
> --- a/drivers/staging/media/tegra-vde/iommu.c
> +++ b/drivers/staging/media/tegra-vde/iommu.c
> @@ -36,8 +36,8 @@ int tegra_vde_iommu_map(struct tegra_vde *vde,
>
> addr = iova_dma_addr(&vde->iova, iova);
>
> - size = iommu_map_sg(vde->domain, addr, sgt->sgl, sgt->nents,
> - IOMMU_READ | IOMMU_WRITE);
> + size = iommu_map_sgtable(vde->domain, addr, sgt,
> + IOMMU_READ | IOMMU_WRITE);
> if (!size) {
> __free_iova(&vde->iova, iova);
> return -ENXIO;
>
Reviewed-by: Dmitry Osipenko <digetx-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-05-14 20:07 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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[not found] ` <20200513133245.6408-1-m.szyprowski@samsung.com>
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2020-05-13 13:32 ` [PATCH v5 23/38] drm: tegra: fix common struct sg_table related issues Marek Szyprowski
2020-05-13 13:32 ` [PATCH v5 28/38] drm: host1x: " Marek Szyprowski
2020-05-13 13:32 ` [PATCH v5 33/38] staging: tegra-vde: " Marek Szyprowski
[not found] ` <20200513133245.6408-33-m.szyprowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
2020-05-14 20:07 ` Dmitry Osipenko
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