| Message ID | 20180622141103.1787-4-christian.koenig@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 06/22/2018 10:11 PM, Christian König wrote: > The caching of SGT's done by the DRM code is actually quite harmful and > should probably removed altogether in the long term. > > Start by providing a separate DMA-buf export implementation in amdgpu. This is > also a prerequisite of unpinned DMA-buf handling. > > v2: fix unintended recursion, remove debugging leftovers > v3: split out from unpinned DMA-buf work > > Signed-off-by: Christian König <christian.koenig@amd.com> > --- > drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 - > drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 - > drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 94 +++++++++++++------------------ > 3 files changed, 39 insertions(+), 57 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h > index d8e0cc08f9db..5e71af8dd3a7 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h > @@ -373,7 +373,6 @@ int amdgpu_gem_object_open(struct drm_gem_object *obj, > void amdgpu_gem_object_close(struct drm_gem_object *obj, > struct drm_file *file_priv); > unsigned long amdgpu_gem_timeout(uint64_t timeout_ns); > -struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object *obj); > struct drm_gem_object * > amdgpu_gem_prime_import_sg_table(struct drm_device *dev, > struct dma_buf_attachment *attach, > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > index a549483032b0..cdf0be85d361 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c > @@ -919,7 +919,6 @@ static struct drm_driver kms_driver = { > .gem_prime_export = amdgpu_gem_prime_export, > .gem_prime_import = amdgpu_gem_prime_import, > .gem_prime_res_obj = amdgpu_gem_prime_res_obj, > - .gem_prime_get_sg_table = amdgpu_gem_prime_get_sg_table, I may miss some patches or important info. Even applied the series of patch, I still could find below code in drm_gem_map_dma_buf(). In this case, it will cause NULL pointer access. Please help me out of here. {{{ sgt = obj->dev->driver->gem_prime_get_sg_table(obj); }}} Jerry > .gem_prime_import_sg_table = amdgpu_gem_prime_import_sg_table, > .gem_prime_vmap = amdgpu_gem_prime_vmap, > .gem_prime_vunmap = amdgpu_gem_prime_vunmap, > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c > index b2286bc41aec..038a8c8488b7 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c > @@ -40,22 +40,6 @@ > > static const struct dma_buf_ops amdgpu_dmabuf_ops; > > -/** > - * amdgpu_gem_prime_get_sg_table - &drm_driver.gem_prime_get_sg_table > - * implementation > - * @obj: GEM buffer object > - * > - * Returns: > - * A scatter/gather table for the pinned pages of the buffer object's memory. > - */ > -struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object *obj) > -{ > - struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); > - int npages = bo->tbo.num_pages; > - > - return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages); > -} > - > /** > * amdgpu_gem_prime_vmap - &dma_buf_ops.vmap implementation > * @obj: GEM buffer object > @@ -189,35 +173,29 @@ amdgpu_gem_prime_import_sg_table(struct drm_device *dev, > } > > /** > - * amdgpu_gem_map_attach - &dma_buf_ops.attach implementation > - * @dma_buf: shared DMA buffer > - * @target_dev: target device > + * amdgpu_gem_map_dma_buf - &dma_buf_ops.map_dma_buf implementation > * @attach: DMA-buf attachment > + * @dir: DMA direction > * > * Makes sure that the shared DMA buffer can be accessed by the target device. > * For now, simply pins it to the GTT domain, where it should be accessible by > * all DMA devices. > * > * Returns: > - * 0 on success or negative error code. > + * sg_table filled with the DMA addresses to use or ERR_PRT with negative error > + * code. > */ > -static int amdgpu_gem_map_attach(struct dma_buf *dma_buf, > - struct dma_buf_attachment *attach) > +static struct sg_table * > +amdgpu_gem_map_dma_buf(struct dma_buf_attachment *attach, > + enum dma_data_direction dir) > { > + struct dma_buf *dma_buf = attach->dmabuf; > struct drm_gem_object *obj = dma_buf->priv; > struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); > struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); > + struct sg_table *sgt; > long r; > > - r = drm_gem_map_attach(dma_buf, attach); > - if (r) > - return r; > - > - r = amdgpu_bo_reserve(bo, false); > - if (unlikely(r != 0)) > - goto error_detach; > - > - > if (attach->dev->driver != adev->dev->driver) { > /* > * Wait for all shared fences to complete before we switch to future > @@ -228,54 +206,62 @@ static int amdgpu_gem_map_attach(struct dma_buf *dma_buf, > MAX_SCHEDULE_TIMEOUT); > if (unlikely(r < 0)) { > DRM_DEBUG_PRIME("Fence wait failed: %li\n", r); > - goto error_unreserve; > + return ERR_PTR(r); > } > } > > /* pin buffer into GTT */ > r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT, NULL); > if (r) > - goto error_unreserve; > + return ERR_PTR(r); > + > + sgt = drm_prime_pages_to_sg(bo->tbo.ttm->pages, bo->tbo.num_pages); > + if (IS_ERR(sgt)) > + return sgt; > + > + if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir, > + DMA_ATTR_SKIP_CPU_SYNC)) > + goto error_free; > > if (attach->dev->driver != adev->dev->driver) > bo->prime_shared_count++; > > -error_unreserve: > - amdgpu_bo_unreserve(bo); > + return sgt; > > -error_detach: > - if (r) > - drm_gem_map_detach(dma_buf, attach); > - return r; > +error_free: > + sg_free_table(sgt); > + kfree(sgt); > + return ERR_PTR(-ENOMEM); > } > > /** > - * amdgpu_gem_map_detach - &dma_buf_ops.detach implementation > - * @dma_buf: shared DMA buffer > + * amdgpu_gem_unmap_dma_buf - &dma_buf_ops.unmap_dma_buf implementation > * @attach: DMA-buf attachment > + * @sgt: sg_table to unmap > + * @dir: DMA direction > * > * This is called when a shared DMA buffer no longer needs to be accessible by > * the other device. For now, simply unpins the buffer from GTT. > */ > -static void amdgpu_gem_map_detach(struct dma_buf *dma_buf, > - struct dma_buf_attachment *attach) > +static void amdgpu_gem_unmap_dma_buf(struct dma_buf_attachment *attach, > + struct sg_table *sgt, > + enum dma_data_direction dir) > { > + struct dma_buf *dma_buf = attach->dmabuf; > struct drm_gem_object *obj = dma_buf->priv; > struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); > struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); > - int ret = 0; > - > - ret = amdgpu_bo_reserve(bo, true); > - if (unlikely(ret != 0)) > - goto error; > > amdgpu_bo_unpin(bo); > + > if (attach->dev->driver != adev->dev->driver && bo->prime_shared_count) > bo->prime_shared_count--; > - amdgpu_bo_unreserve(bo); > > -error: > - drm_gem_map_detach(dma_buf, attach); > + if (sgt) { > + dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir); > + sg_free_table(sgt); > + kfree(sgt); > + } > } > > /** > @@ -333,10 +319,8 @@ static int amdgpu_gem_begin_cpu_access(struct dma_buf *dma_buf, > } > > static const struct dma_buf_ops amdgpu_dmabuf_ops = { > - .attach = amdgpu_gem_map_attach, > - .detach = amdgpu_gem_map_detach, > - .map_dma_buf = drm_gem_map_dma_buf, > - .unmap_dma_buf = drm_gem_unmap_dma_buf, > + .map_dma_buf = amdgpu_gem_map_dma_buf, > + .unmap_dma_buf = amdgpu_gem_unmap_dma_buf, > .release = drm_gem_dmabuf_release, > .begin_cpu_access = amdgpu_gem_begin_cpu_access, > .map = drm_gem_dmabuf_kmap, >
Am 28.06.2018 um 11:58 schrieb Zhang, Jerry (Junwei): > On 06/22/2018 10:11 PM, Christian König wrote: >> The caching of SGT's done by the DRM code is actually quite harmful and >> should probably removed altogether in the long term. >> >> Start by providing a separate DMA-buf export implementation in >> amdgpu. This is >> also a prerequisite of unpinned DMA-buf handling. >> >> v2: fix unintended recursion, remove debugging leftovers >> v3: split out from unpinned DMA-buf work >> >> Signed-off-by: Christian König <christian.koenig@amd.com> >> --- >> drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 - >> drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 - >> drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 94 >> +++++++++++++------------------ >> 3 files changed, 39 insertions(+), 57 deletions(-) >> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h >> b/drivers/gpu/drm/amd/amdgpu/amdgpu.h >> index d8e0cc08f9db..5e71af8dd3a7 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h >> @@ -373,7 +373,6 @@ int amdgpu_gem_object_open(struct drm_gem_object >> *obj, >> void amdgpu_gem_object_close(struct drm_gem_object *obj, >> struct drm_file *file_priv); >> unsigned long amdgpu_gem_timeout(uint64_t timeout_ns); >> -struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object >> *obj); >> struct drm_gem_object * >> amdgpu_gem_prime_import_sg_table(struct drm_device *dev, >> struct dma_buf_attachment *attach, >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c >> index a549483032b0..cdf0be85d361 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c >> @@ -919,7 +919,6 @@ static struct drm_driver kms_driver = { >> .gem_prime_export = amdgpu_gem_prime_export, >> .gem_prime_import = amdgpu_gem_prime_import, >> .gem_prime_res_obj = amdgpu_gem_prime_res_obj, >> - .gem_prime_get_sg_table = amdgpu_gem_prime_get_sg_table, > > I may miss some patches or important info. > > Even applied the series of patch, I still could find below code in > drm_gem_map_dma_buf(). > In this case, it will cause NULL pointer access. Please help me out of > here. > {{{ > sgt = obj->dev->driver->gem_prime_get_sg_table(obj); > }}} Take a look at the change a bit further down. > > Jerry > >> .gem_prime_import_sg_table = amdgpu_gem_prime_import_sg_table, >> .gem_prime_vmap = amdgpu_gem_prime_vmap, >> .gem_prime_vunmap = amdgpu_gem_prime_vunmap, >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c >> index b2286bc41aec..038a8c8488b7 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c >> @@ -40,22 +40,6 @@ >> >> static const struct dma_buf_ops amdgpu_dmabuf_ops; >> >> -/** >> - * amdgpu_gem_prime_get_sg_table - &drm_driver.gem_prime_get_sg_table >> - * implementation >> - * @obj: GEM buffer object >> - * >> - * Returns: >> - * A scatter/gather table for the pinned pages of the buffer >> object's memory. >> - */ >> -struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object >> *obj) >> -{ >> - struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); >> - int npages = bo->tbo.num_pages; >> - >> - return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages); >> -} >> - >> /** >> * amdgpu_gem_prime_vmap - &dma_buf_ops.vmap implementation >> * @obj: GEM buffer object >> @@ -189,35 +173,29 @@ amdgpu_gem_prime_import_sg_table(struct >> drm_device *dev, >> } >> >> /** >> - * amdgpu_gem_map_attach - &dma_buf_ops.attach implementation >> - * @dma_buf: shared DMA buffer >> - * @target_dev: target device >> + * amdgpu_gem_map_dma_buf - &dma_buf_ops.map_dma_buf implementation >> * @attach: DMA-buf attachment >> + * @dir: DMA direction >> * >> * Makes sure that the shared DMA buffer can be accessed by the >> target device. >> * For now, simply pins it to the GTT domain, where it should be >> accessible by >> * all DMA devices. >> * >> * Returns: >> - * 0 on success or negative error code. >> + * sg_table filled with the DMA addresses to use or ERR_PRT with >> negative error >> + * code. >> */ >> -static int amdgpu_gem_map_attach(struct dma_buf *dma_buf, >> - struct dma_buf_attachment *attach) >> +static struct sg_table * >> +amdgpu_gem_map_dma_buf(struct dma_buf_attachment *attach, >> + enum dma_data_direction dir) >> { >> + struct dma_buf *dma_buf = attach->dmabuf; >> struct drm_gem_object *obj = dma_buf->priv; >> struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); >> struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); >> + struct sg_table *sgt; >> long r; >> >> - r = drm_gem_map_attach(dma_buf, attach); >> - if (r) >> - return r; >> - >> - r = amdgpu_bo_reserve(bo, false); >> - if (unlikely(r != 0)) >> - goto error_detach; >> - >> - >> if (attach->dev->driver != adev->dev->driver) { >> /* >> * Wait for all shared fences to complete before we switch >> to future >> @@ -228,54 +206,62 @@ static int amdgpu_gem_map_attach(struct dma_buf >> *dma_buf, >> MAX_SCHEDULE_TIMEOUT); >> if (unlikely(r < 0)) { >> DRM_DEBUG_PRIME("Fence wait failed: %li\n", r); >> - goto error_unreserve; >> + return ERR_PTR(r); >> } >> } >> >> /* pin buffer into GTT */ >> r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT, NULL); >> if (r) >> - goto error_unreserve; >> + return ERR_PTR(r); >> + >> + sgt = drm_prime_pages_to_sg(bo->tbo.ttm->pages, bo->tbo.num_pages); >> + if (IS_ERR(sgt)) >> + return sgt; >> + >> + if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir, >> + DMA_ATTR_SKIP_CPU_SYNC)) >> + goto error_free; >> >> if (attach->dev->driver != adev->dev->driver) >> bo->prime_shared_count++; >> >> -error_unreserve: >> - amdgpu_bo_unreserve(bo); >> + return sgt; >> >> -error_detach: >> - if (r) >> - drm_gem_map_detach(dma_buf, attach); >> - return r; >> +error_free: >> + sg_free_table(sgt); >> + kfree(sgt); >> + return ERR_PTR(-ENOMEM); >> } >> >> /** >> - * amdgpu_gem_map_detach - &dma_buf_ops.detach implementation >> - * @dma_buf: shared DMA buffer >> + * amdgpu_gem_unmap_dma_buf - &dma_buf_ops.unmap_dma_buf implementation >> * @attach: DMA-buf attachment >> + * @sgt: sg_table to unmap >> + * @dir: DMA direction >> * >> * This is called when a shared DMA buffer no longer needs to be >> accessible by >> * the other device. For now, simply unpins the buffer from GTT. >> */ >> -static void amdgpu_gem_map_detach(struct dma_buf *dma_buf, >> - struct dma_buf_attachment *attach) >> +static void amdgpu_gem_unmap_dma_buf(struct dma_buf_attachment *attach, >> + struct sg_table *sgt, >> + enum dma_data_direction dir) >> { >> + struct dma_buf *dma_buf = attach->dmabuf; >> struct drm_gem_object *obj = dma_buf->priv; >> struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); >> struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); >> - int ret = 0; >> - >> - ret = amdgpu_bo_reserve(bo, true); >> - if (unlikely(ret != 0)) >> - goto error; >> >> amdgpu_bo_unpin(bo); >> + >> if (attach->dev->driver != adev->dev->driver && >> bo->prime_shared_count) >> bo->prime_shared_count--; >> - amdgpu_bo_unreserve(bo); >> >> -error: >> - drm_gem_map_detach(dma_buf, attach); >> + if (sgt) { >> + dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir); >> + sg_free_table(sgt); >> + kfree(sgt); >> + } >> } >> >> /** >> @@ -333,10 +319,8 @@ static int amdgpu_gem_begin_cpu_access(struct >> dma_buf *dma_buf, >> } >> >> static const struct dma_buf_ops amdgpu_dmabuf_ops = { >> - .attach = amdgpu_gem_map_attach, >> - .detach = amdgpu_gem_map_detach, >> - .map_dma_buf = drm_gem_map_dma_buf, >> - .unmap_dma_buf = drm_gem_unmap_dma_buf, Here we are stopping to use drm_gem_map_dma_buf(), so we don't need amdgpu_gem_prime_get_sg_table() any more either. Christian. >> + .map_dma_buf = amdgpu_gem_map_dma_buf, >> + .unmap_dma_buf = amdgpu_gem_unmap_dma_buf, >> .release = drm_gem_dmabuf_release, >> .begin_cpu_access = amdgpu_gem_begin_cpu_access, >> .map = drm_gem_dmabuf_kmap, >>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index d8e0cc08f9db..5e71af8dd3a7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -373,7 +373,6 @@ int amdgpu_gem_object_open(struct drm_gem_object *obj, void amdgpu_gem_object_close(struct drm_gem_object *obj, struct drm_file *file_priv); unsigned long amdgpu_gem_timeout(uint64_t timeout_ns); -struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object *obj); struct drm_gem_object * amdgpu_gem_prime_import_sg_table(struct drm_device *dev, struct dma_buf_attachment *attach, diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index a549483032b0..cdf0be85d361 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -919,7 +919,6 @@ static struct drm_driver kms_driver = { .gem_prime_export = amdgpu_gem_prime_export, .gem_prime_import = amdgpu_gem_prime_import, .gem_prime_res_obj = amdgpu_gem_prime_res_obj, - .gem_prime_get_sg_table = amdgpu_gem_prime_get_sg_table, .gem_prime_import_sg_table = amdgpu_gem_prime_import_sg_table, .gem_prime_vmap = amdgpu_gem_prime_vmap, .gem_prime_vunmap = amdgpu_gem_prime_vunmap, diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c index b2286bc41aec..038a8c8488b7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c @@ -40,22 +40,6 @@ static const struct dma_buf_ops amdgpu_dmabuf_ops; -/** - * amdgpu_gem_prime_get_sg_table - &drm_driver.gem_prime_get_sg_table - * implementation - * @obj: GEM buffer object - * - * Returns: - * A scatter/gather table for the pinned pages of the buffer object's memory. - */ -struct sg_table *amdgpu_gem_prime_get_sg_table(struct drm_gem_object *obj) -{ - struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); - int npages = bo->tbo.num_pages; - - return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages); -} - /** * amdgpu_gem_prime_vmap - &dma_buf_ops.vmap implementation * @obj: GEM buffer object @@ -189,35 +173,29 @@ amdgpu_gem_prime_import_sg_table(struct drm_device *dev, } /** - * amdgpu_gem_map_attach - &dma_buf_ops.attach implementation - * @dma_buf: shared DMA buffer - * @target_dev: target device + * amdgpu_gem_map_dma_buf - &dma_buf_ops.map_dma_buf implementation * @attach: DMA-buf attachment + * @dir: DMA direction * * Makes sure that the shared DMA buffer can be accessed by the target device. * For now, simply pins it to the GTT domain, where it should be accessible by * all DMA devices. * * Returns: - * 0 on success or negative error code. + * sg_table filled with the DMA addresses to use or ERR_PRT with negative error + * code. */ -static int amdgpu_gem_map_attach(struct dma_buf *dma_buf, - struct dma_buf_attachment *attach) +static struct sg_table * +amdgpu_gem_map_dma_buf(struct dma_buf_attachment *attach, + enum dma_data_direction dir) { + struct dma_buf *dma_buf = attach->dmabuf; struct drm_gem_object *obj = dma_buf->priv; struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); + struct sg_table *sgt; long r; - r = drm_gem_map_attach(dma_buf, attach); - if (r) - return r; - - r = amdgpu_bo_reserve(bo, false); - if (unlikely(r != 0)) - goto error_detach; - - if (attach->dev->driver != adev->dev->driver) { /* * Wait for all shared fences to complete before we switch to future @@ -228,54 +206,62 @@ static int amdgpu_gem_map_attach(struct dma_buf *dma_buf, MAX_SCHEDULE_TIMEOUT); if (unlikely(r < 0)) { DRM_DEBUG_PRIME("Fence wait failed: %li\n", r); - goto error_unreserve; + return ERR_PTR(r); } } /* pin buffer into GTT */ r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT, NULL); if (r) - goto error_unreserve; + return ERR_PTR(r); + + sgt = drm_prime_pages_to_sg(bo->tbo.ttm->pages, bo->tbo.num_pages); + if (IS_ERR(sgt)) + return sgt; + + if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir, + DMA_ATTR_SKIP_CPU_SYNC)) + goto error_free; if (attach->dev->driver != adev->dev->driver) bo->prime_shared_count++; -error_unreserve: - amdgpu_bo_unreserve(bo); + return sgt; -error_detach: - if (r) - drm_gem_map_detach(dma_buf, attach); - return r; +error_free: + sg_free_table(sgt); + kfree(sgt); + return ERR_PTR(-ENOMEM); } /** - * amdgpu_gem_map_detach - &dma_buf_ops.detach implementation - * @dma_buf: shared DMA buffer + * amdgpu_gem_unmap_dma_buf - &dma_buf_ops.unmap_dma_buf implementation * @attach: DMA-buf attachment + * @sgt: sg_table to unmap + * @dir: DMA direction * * This is called when a shared DMA buffer no longer needs to be accessible by * the other device. For now, simply unpins the buffer from GTT. */ -static void amdgpu_gem_map_detach(struct dma_buf *dma_buf, - struct dma_buf_attachment *attach) +static void amdgpu_gem_unmap_dma_buf(struct dma_buf_attachment *attach, + struct sg_table *sgt, + enum dma_data_direction dir) { + struct dma_buf *dma_buf = attach->dmabuf; struct drm_gem_object *obj = dma_buf->priv; struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); - int ret = 0; - - ret = amdgpu_bo_reserve(bo, true); - if (unlikely(ret != 0)) - goto error; amdgpu_bo_unpin(bo); + if (attach->dev->driver != adev->dev->driver && bo->prime_shared_count) bo->prime_shared_count--; - amdgpu_bo_unreserve(bo); -error: - drm_gem_map_detach(dma_buf, attach); + if (sgt) { + dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir); + sg_free_table(sgt); + kfree(sgt); + } } /** @@ -333,10 +319,8 @@ static int amdgpu_gem_begin_cpu_access(struct dma_buf *dma_buf, } static const struct dma_buf_ops amdgpu_dmabuf_ops = { - .attach = amdgpu_gem_map_attach, - .detach = amdgpu_gem_map_detach, - .map_dma_buf = drm_gem_map_dma_buf, - .unmap_dma_buf = drm_gem_unmap_dma_buf, + .map_dma_buf = amdgpu_gem_map_dma_buf, + .unmap_dma_buf = amdgpu_gem_unmap_dma_buf, .release = drm_gem_dmabuf_release, .begin_cpu_access = amdgpu_gem_begin_cpu_access, .map = drm_gem_dmabuf_kmap,
The caching of SGT's done by the DRM code is actually quite harmful and should probably removed altogether in the long term. Start by providing a separate DMA-buf export implementation in amdgpu. This is also a prerequisite of unpinned DMA-buf handling. v2: fix unintended recursion, remove debugging leftovers v3: split out from unpinned DMA-buf work Signed-off-by: Christian König <christian.koenig@amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 - drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 - drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 94 +++++++++++++------------------ 3 files changed, 39 insertions(+), 57 deletions(-)