| Message ID | 20200420060834.44461-1-amistry@google.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 9a67bc4aac82d18132e8a5677926f05d43e44e77 |
| Headers | show |
| Series | drm/mediatek: stop iterating dma addresses when sg_dma_len() == 0 | expand |
Hi, Anand: Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > If dma_map_sg() merges pages when creating the mapping, only the first > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > entries with sg_dma_len() == 0. > > Signed-off-by: Anand K Mistry <amistry@google.com> > --- > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > expected = sg_dma_address(sg->sgl); > for_each_sg(sg->sgl, s, sg->nents, i) { > + if (!sg_dma_len(s)) > + break; I think this should be 'continue' Regards, Chun-Kuang. > + > if (sg_dma_address(s) != expected) { > DRM_ERROR("sg_table is not contiguous"); > ret = -EINVAL; > -- > 2.26.1.301.g55bc3eb7cb9-goog > > > _______________________________________________ > Linux-mediatek mailing list > Linux-mediatek@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-mediatek
On Sun, 26 Apr 2020 at 18:04, Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > Hi, Anand: > > Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > > > If dma_map_sg() merges pages when creating the mapping, only the first > > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > > entries with sg_dma_len() == 0. > > > > Signed-off-by: Anand K Mistry <amistry@google.com> > > --- > > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > > > expected = sg_dma_address(sg->sgl); > > for_each_sg(sg->sgl, s, sg->nents, i) { > > + if (!sg_dma_len(s)) > > + break; > > I think this should be 'continue' scatterlist.h has the comment: /* * These macros should be used after a dma_map_sg call has been done * to get bus addresses of each of the SG entries and their lengths. * You should only work with the number of sg entries dma_map_sg * returns, or alternatively stop on the first sg_dma_len(sg) which * is 0. */ So breaking on the first sg_dma_len(sg) == 0 appears to be (one of) the documented approach. > > Regards, > Chun-Kuang. > > > + > > if (sg_dma_address(s) != expected) { > > DRM_ERROR("sg_table is not contiguous"); > > ret = -EINVAL; > > -- > > 2.26.1.301.g55bc3eb7cb9-goog > > > > > > _______________________________________________ > > Linux-mediatek mailing list > > Linux-mediatek@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
Hi, Anand, Anand K. Mistry <amistry@chromium.org> 於 2020年4月28日 週二 上午9:54寫道： > > On Sun, 26 Apr 2020 at 18:04, Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > Hi, Anand: > > > > Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > > > > > If dma_map_sg() merges pages when creating the mapping, only the first > > > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > > > entries with sg_dma_len() == 0. > > > > > > Signed-off-by: Anand K Mistry <amistry@google.com> > > > --- > > > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > > > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > > > > > expected = sg_dma_address(sg->sgl); > > > for_each_sg(sg->sgl, s, sg->nents, i) { > > > + if (!sg_dma_len(s)) > > > + break; > > > > I think this should be 'continue' > > scatterlist.h has the comment: > /* > * These macros should be used after a dma_map_sg call has been done > * to get bus addresses of each of the SG entries and their lengths. > * You should only work with the number of sg entries dma_map_sg > * returns, or alternatively stop on the first sg_dma_len(sg) which > * is 0. > */ > > So breaking on the first sg_dma_len(sg) == 0 appears to be (one of) > the documented approach. > Okay, you're right. So Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> > > > > Regards, > > Chun-Kuang. > > > > > + > > > if (sg_dma_address(s) != expected) { > > > DRM_ERROR("sg_table is not contiguous"); > > > ret = -EINVAL; > > > -- > > > 2.26.1.301.g55bc3eb7cb9-goog > > > > > > > > > _______________________________________________ > > > Linux-mediatek mailing list > > > Linux-mediatek@lists.infradead.org > > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
Hi, Anand, Chun-Kuang Hu <chunkuang.hu@kernel.org> 於 2020年4月29日 週三 上午12:37寫道： > > Hi, Anand, > > Anand K. Mistry <amistry@chromium.org> 於 2020年4月28日 週二 上午9:54寫道： > > > > On Sun, 26 Apr 2020 at 18:04, Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > > > Hi, Anand: > > > > > > Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > > > > > > > If dma_map_sg() merges pages when creating the mapping, only the first > > > > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > > > > entries with sg_dma_len() == 0. > > > > > > > > Signed-off-by: Anand K Mistry <amistry@google.com> Author should sign off this patch, please give a sign off tag by author. Regards, Chun-Kuang. > > > > --- > > > > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > > > > 1 file changed, 3 insertions(+) > > > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > > > > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > > > > > > > expected = sg_dma_address(sg->sgl); > > > > for_each_sg(sg->sgl, s, sg->nents, i) { > > > > + if (!sg_dma_len(s)) > > > > + break; > > > > > > I think this should be 'continue' > > > > scatterlist.h has the comment: > > /* > > * These macros should be used after a dma_map_sg call has been done > > * to get bus addresses of each of the SG entries and their lengths. > > * You should only work with the number of sg entries dma_map_sg > > * returns, or alternatively stop on the first sg_dma_len(sg) which > > * is 0. > > */ > > > > So breaking on the first sg_dma_len(sg) == 0 appears to be (one of) > > the documented approach. > > > > Okay, you're right. So > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> > > > > > > > Regards, > > > Chun-Kuang. > > > > > > > + > > > > if (sg_dma_address(s) != expected) { > > > > DRM_ERROR("sg_table is not contiguous"); > > > > ret = -EINVAL; > > > > -- > > > > 2.26.1.301.g55bc3eb7cb9-goog > > > > > > > > > > > > _______________________________________________ > > > > Linux-mediatek mailing list > > > > Linux-mediatek@lists.infradead.org > > > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
On Wed, May 6, 2020 at 10:25 AM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > Hi, Anand, > > Chun-Kuang Hu <chunkuang.hu@kernel.org> 於 2020年4月29日 週三 上午12:37寫道： > > > > Hi, Anand, > > > > Anand K. Mistry <amistry@chromium.org> 於 2020年4月28日 週二 上午9:54寫道： > > > > > > On Sun, 26 Apr 2020 at 18:04, Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > > > > > Hi, Anand: > > > > > > > > Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > > > > > > > > > If dma_map_sg() merges pages when creating the mapping, only the first > > > > > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > > > > > entries with sg_dma_len() == 0. > > > > > > > > > > Signed-off-by: Anand K Mistry <amistry@google.com> > > Author should sign off this patch, please give a sign off tag by author. Sorry, email issues meant i sent the patch from a different account. Should I re-send the patch from the same account as the sign-off line? I'm still working my way through the kernel patch process. > > Regards, > Chun-Kuang. > > > > > > --- > > > > > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > > > > > 1 file changed, 3 insertions(+) > > > > > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > > > > > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > > > > > > > > > expected = sg_dma_address(sg->sgl); > > > > > for_each_sg(sg->sgl, s, sg->nents, i) { > > > > > + if (!sg_dma_len(s)) > > > > > + break; > > > > > > > > I think this should be 'continue' > > > > > > scatterlist.h has the comment: > > > /* > > > * These macros should be used after a dma_map_sg call has been done > > > * to get bus addresses of each of the SG entries and their lengths. > > > * You should only work with the number of sg entries dma_map_sg > > > * returns, or alternatively stop on the first sg_dma_len(sg) which > > > * is 0. > > > */ > > > > > > So breaking on the first sg_dma_len(sg) == 0 appears to be (one of) > > > the documented approach. > > > > > > > Okay, you're right. So > > > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> > > > > > > > > > > Regards, > > > > Chun-Kuang. > > > > > > > > > + > > > > > if (sg_dma_address(s) != expected) { > > > > > DRM_ERROR("sg_table is not contiguous"); > > > > > ret = -EINVAL; > > > > > -- > > > > > 2.26.1.301.g55bc3eb7cb9-goog > > > > > > > > > > > > > > > _______________________________________________ > > > > > Linux-mediatek mailing list > > > > > Linux-mediatek@lists.infradead.org > > > > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
Hi, Anand: Anand Mistry <amistry@chromium.org> 於 2020年5月6日 週三 下午7:03寫道： > > On Wed, May 6, 2020 at 10:25 AM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > Hi, Anand, > > > > Chun-Kuang Hu <chunkuang.hu@kernel.org> 於 2020年4月29日 週三 上午12:37寫道： > > > > > > Hi, Anand, > > > > > > Anand K. Mistry <amistry@chromium.org> 於 2020年4月28日 週二 上午9:54寫道： > > > > > > > > On Sun, 26 Apr 2020 at 18:04, Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > > > > > > > Hi, Anand: > > > > > > > > > > Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > > > > > > > > > > > If dma_map_sg() merges pages when creating the mapping, only the first > > > > > > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > > > > > > entries with sg_dma_len() == 0. > > > > > > > > > > > > Signed-off-by: Anand K Mistry <amistry@google.com> > > > > Author should sign off this patch, please give a sign off tag by author. > > Sorry, email issues meant i sent the patch from a different account. > Should I re-send the > patch from the same account as the sign-off line? I'm still working my > way through the kernel patch process. > If you want to use chromium account, you could simply reply this email with a sign-off-by tag of chromium account. Regards, Chun-Kuang. > > > > Regards, > > Chun-Kuang. > > > > > > > > --- > > > > > > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > > > > > > 1 file changed, 3 insertions(+) > > > > > > > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > > > > > > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > > > > > > > > > > > expected = sg_dma_address(sg->sgl); > > > > > > for_each_sg(sg->sgl, s, sg->nents, i) { > > > > > > + if (!sg_dma_len(s)) > > > > > > + break; > > > > > > > > > > I think this should be 'continue' > > > > > > > > scatterlist.h has the comment: > > > > /* > > > > * These macros should be used after a dma_map_sg call has been done > > > > * to get bus addresses of each of the SG entries and their lengths. > > > > * You should only work with the number of sg entries dma_map_sg > > > > * returns, or alternatively stop on the first sg_dma_len(sg) which > > > > * is 0. > > > > */ > > > > > > > > So breaking on the first sg_dma_len(sg) == 0 appears to be (one of) > > > > the documented approach. > > > > > > > > > > Okay, you're right. So > > > > > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> > > > > > > > > > > > > > Regards, > > > > > Chun-Kuang. > > > > > > > > > > > + > > > > > > if (sg_dma_address(s) != expected) { > > > > > > DRM_ERROR("sg_table is not contiguous"); > > > > > > ret = -EINVAL; > > > > > > -- > > > > > > 2.26.1.301.g55bc3eb7cb9-goog > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > > > Linux-mediatek mailing list > > > > > > Linux-mediatek@lists.infradead.org > > > > > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
On Wed, May 6, 2020 at 10:59 PM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > Hi, Anand: > > Anand Mistry <amistry@chromium.org> 於 2020年5月6日 週三 下午7:03寫道： > > > > On Wed, May 6, 2020 at 10:25 AM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > > > Hi, Anand, > > > > > > Chun-Kuang Hu <chunkuang.hu@kernel.org> 於 2020年4月29日 週三 上午12:37寫道： > > > > > > > > Hi, Anand, > > > > > > > > Anand K. Mistry <amistry@chromium.org> 於 2020年4月28日 週二 上午9:54寫道： > > > > > > > > > > On Sun, 26 Apr 2020 at 18:04, Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > > > > > > > > > Hi, Anand: > > > > > > > > > > > > Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > > > > > > > > > > > > > If dma_map_sg() merges pages when creating the mapping, only the first > > > > > > > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > > > > > > > entries with sg_dma_len() == 0. > > > > > > > > > > > > > > Signed-off-by: Anand K Mistry <amistry@google.com> > > > > > > Author should sign off this patch, please give a sign off tag by author. > > > > Sorry, email issues meant i sent the patch from a different account. > > Should I re-send the > > patch from the same account as the sign-off line? I'm still working my > > way through the kernel patch process. > > > > If you want to use chromium account, you could simply reply this email > with a sign-off-by tag of chromium account. Ack. This is fine for now. I'll try doing it better with the next patch. Signed-off-by: Anand K Mistry <amistry@chromium.org> > > Regards, > Chun-Kuang. > > > > > > > Regards, > > > Chun-Kuang. > > > > > > > > > > --- > > > > > > > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > > > > > > > 1 file changed, 3 insertions(+) > > > > > > > > > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > > > > > > > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > > > > > > > > > > > > > expected = sg_dma_address(sg->sgl); > > > > > > > for_each_sg(sg->sgl, s, sg->nents, i) { > > > > > > > + if (!sg_dma_len(s)) > > > > > > > + break; > > > > > > > > > > > > I think this should be 'continue' > > > > > > > > > > scatterlist.h has the comment: > > > > > /* > > > > > * These macros should be used after a dma_map_sg call has been done > > > > > * to get bus addresses of each of the SG entries and their lengths. > > > > > * You should only work with the number of sg entries dma_map_sg > > > > > * returns, or alternatively stop on the first sg_dma_len(sg) which > > > > > * is 0. > > > > > */ > > > > > > > > > > So breaking on the first sg_dma_len(sg) == 0 appears to be (one of) > > > > > the documented approach. > > > > > > > > > > > > > Okay, you're right. So > > > > > > > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> > > > > > > > > > > > > > > > > Regards, > > > > > > Chun-Kuang. > > > > > > > > > > > > > + > > > > > > > if (sg_dma_address(s) != expected) { > > > > > > > DRM_ERROR("sg_table is not contiguous"); > > > > > > > ret = -EINVAL; > > > > > > > -- > > > > > > > 2.26.1.301.g55bc3eb7cb9-goog > > > > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > > > > Linux-mediatek mailing list > > > > > > > Linux-mediatek@lists.infradead.org > > > > > > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
Hi, Anand: Anand Mistry <amistry@chromium.org> 於 2020年5月7日 週四 下午7:56寫道： > > On Wed, May 6, 2020 at 10:59 PM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > Hi, Anand: > > > > Anand Mistry <amistry@chromium.org> 於 2020年5月6日 週三 下午7:03寫道： > > > > > > On Wed, May 6, 2020 at 10:25 AM Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > > > > > Hi, Anand, > > > > > > > > Chun-Kuang Hu <chunkuang.hu@kernel.org> 於 2020年4月29日 週三 上午12:37寫道： > > > > > > > > > > Hi, Anand, > > > > > > > > > > Anand K. Mistry <amistry@chromium.org> 於 2020年4月28日 週二 上午9:54寫道： > > > > > > > > > > > > On Sun, 26 Apr 2020 at 18:04, Chun-Kuang Hu <chunkuang.hu@kernel.org> wrote: > > > > > > > > > > > > > > Hi, Anand: > > > > > > > > > > > > > > Anand K Mistry <amistry@chromium.org> 於 2020年4月20日 週一 下午2:09寫道： > > > > > > > > > > > > > > > > If dma_map_sg() merges pages when creating the mapping, only the first > > > > > > > > entries will have a valid sg_dma_address() and sg_dma_len(), followed by > > > > > > > > entries with sg_dma_len() == 0. > > > > > > > > > > > > > > > > Signed-off-by: Anand K Mistry <amistry@google.com> > > > > > > > > Author should sign off this patch, please give a sign off tag by author. > > > > > > Sorry, email issues meant i sent the patch from a different account. > > > Should I re-send the > > > patch from the same account as the sign-off line? I'm still working my > > > way through the kernel patch process. > > > > > > > If you want to use chromium account, you could simply reply this email > > with a sign-off-by tag of chromium account. > > Ack. As path of least resistance, here: > > Signed-off-by: Anand K Mistry <amistry@chromium.org> > Applied to mediatek-drm-next [1], thanks. [1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-next Regards, Chun-Kuang. > > > > > Regards, > > Chun-Kuang. > > > > > > > > > > Regards, > > > > Chun-Kuang. > > > > > > > > > > > > --- > > > > > > > > drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ > > > > > > > > 1 file changed, 3 insertions(+) > > > > > > > > > > > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > > > index b04a3c2b111e09..f8fd8b98c30e3d 100644 > > > > > > > > --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > > > +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c > > > > > > > > @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, > > > > > > > > > > > > > > > > expected = sg_dma_address(sg->sgl); > > > > > > > > for_each_sg(sg->sgl, s, sg->nents, i) { > > > > > > > > + if (!sg_dma_len(s)) > > > > > > > > + break; > > > > > > > > > > > > > > I think this should be 'continue' > > > > > > > > > > > > scatterlist.h has the comment: > > > > > > /* > > > > > > * These macros should be used after a dma_map_sg call has been done > > > > > > * to get bus addresses of each of the SG entries and their lengths. > > > > > > * You should only work with the number of sg entries dma_map_sg > > > > > > * returns, or alternatively stop on the first sg_dma_len(sg) which > > > > > > * is 0. > > > > > > */ > > > > > > > > > > > > So breaking on the first sg_dma_len(sg) == 0 appears to be (one of) > > > > > > the documented approach. > > > > > > > > > > > > > > > > Okay, you're right. So > > > > > > > > > > Reviewed-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> > > > > > > > > > > > > > > > > > > > Regards, > > > > > > > Chun-Kuang. > > > > > > > > > > > > > > > + > > > > > > > > if (sg_dma_address(s) != expected) { > > > > > > > > DRM_ERROR("sg_table is not contiguous"); > > > > > > > > ret = -EINVAL; > > > > > > > > -- > > > > > > > > 2.26.1.301.g55bc3eb7cb9-goog > > > > > > > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > > > > > Linux-mediatek mailing list > > > > > > > > Linux-mediatek@lists.infradead.org > > > > > > > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_gem.c b/drivers/gpu/drm/mediatek/mtk_drm_gem.c index b04a3c2b111e09..f8fd8b98c30e3d 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_gem.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_gem.c @@ -224,6 +224,9 @@ struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, expected = sg_dma_address(sg->sgl); for_each_sg(sg->sgl, s, sg->nents, i) { + if (!sg_dma_len(s)) + break; + if (sg_dma_address(s) != expected) { DRM_ERROR("sg_table is not contiguous"); ret = -EINVAL;
If dma_map_sg() merges pages when creating the mapping, only the first entries will have a valid sg_dma_address() and sg_dma_len(), followed by entries with sg_dma_len() == 0. Signed-off-by: Anand K Mistry <amistry@google.com> --- drivers/gpu/drm/mediatek/mtk_drm_gem.c | 3 +++ 1 file changed, 3 insertions(+)