| Message ID | 20210302004624.31294-9-senozhatsky@chromium.org |
|---|---|
| State | New, archived |
| Headers | show |
| Series |
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| Related | show |
On 02/03/2021 01:46, Sergey Senozhatsky wrote: > This adds support for new noncontiguous DMA API, which > requires allocators to have two execution branches: one > for the current API, and one for the new one. > > Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> > [hch: untested conversion to the ne API] > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > .../common/videobuf2/videobuf2-dma-contig.c | 141 +++++++++++++++--- > 1 file changed, 117 insertions(+), 24 deletions(-) > > diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c > index 1e218bc440c6..d6a9f7b682f3 100644 > --- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c > +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c > @@ -17,6 +17,7 @@ > #include <linux/sched.h> > #include <linux/slab.h> > #include <linux/dma-mapping.h> > +#include <linux/highmem.h> > > #include <media/videobuf2-v4l2.h> > #include <media/videobuf2-dma-contig.h> > @@ -42,8 +43,14 @@ struct vb2_dc_buf { > struct dma_buf_attachment *db_attach; > > struct vb2_buffer *vb; > + unsigned int non_coherent_mem:1; Just use a bool here. > }; > > +static bool vb2_dc_is_coherent(struct vb2_dc_buf *buf) > +{ > + return !buf->non_coherent_mem; > +} I would just drop this 'helper' function. Testing against buf->non_coherent_mem seems perfectly understandable to me. And better than negating that bool in this helper function. You can choose to invert non_coherent_mem: i.e. add a coherent_mem bool instead of a non_coherent_mem bool if you think that is easier to understand. It's set in just one place (alloc), so that's easy enough. Calling it 'bool is_coherent;' would perhaps be the easiest to understand. > + > /*********************************************/ > /* scatterlist table functions */ > /*********************************************/ > @@ -78,12 +85,21 @@ static void *vb2_dc_cookie(struct vb2_buffer *vb, void *buf_priv) > static void *vb2_dc_vaddr(struct vb2_buffer *vb, void *buf_priv) > { > struct vb2_dc_buf *buf = buf_priv; > - struct dma_buf_map map; > - int ret; > > - if (!buf->vaddr && buf->db_attach) { > - ret = dma_buf_vmap(buf->db_attach->dmabuf, &map); > - buf->vaddr = ret ? NULL : map.vaddr; > + if (buf->vaddr) > + return buf->vaddr; > + > + if (buf->db_attach) { > + struct dma_buf_map map; > + > + if (!dma_buf_vmap(buf->db_attach->dmabuf, &map)) > + buf->vaddr = map.vaddr; > + } > + > + if (!vb2_dc_is_coherent(buf)) { > + buf->vaddr = dma_vmap_noncontiguous(buf->dev, > + buf->size, > + buf->dma_sgt); > } > > return buf->vaddr; > @@ -101,13 +117,26 @@ static void vb2_dc_prepare(void *buf_priv) > struct vb2_dc_buf *buf = buf_priv; > struct sg_table *sgt = buf->dma_sgt; > > + /* This takes care of DMABUF and user-enforced cache sync hint */ > if (buf->vb->skip_cache_sync_on_prepare) > return; > > + /* > + * Coherent MMAP buffers do not need to be synced, unlike coherent > + * USERPTR and non-coherent MMAP buffers. > + */ > + if (buf->vb->memory == V4L2_MEMORY_MMAP && vb2_dc_is_coherent(buf)) > + return; > + > if (!sgt) > return; > > + /* For both USERPTR and non-coherent MMAP */ > dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir); > + > + /* Non-coherrent MMAP only */ Typo: coherrent -> coherent > + if (!vb2_dc_is_coherent(buf) && buf->vaddr) > + flush_kernel_vmap_range(buf->vaddr, buf->size); > } > > static void vb2_dc_finish(void *buf_priv) > @@ -115,19 +144,46 @@ static void vb2_dc_finish(void *buf_priv) > struct vb2_dc_buf *buf = buf_priv; > struct sg_table *sgt = buf->dma_sgt; > > + /* This takes care of DMABUF and user-enforced cache sync hint */ > if (buf->vb->skip_cache_sync_on_finish) > return; > > + /* > + * Coherent MMAP buffers do not need to be synced, unlike coherent > + * USERPTR and non-coherent MMAP buffers. > + */ > + if (buf->vb->memory == V4L2_MEMORY_MMAP && vb2_dc_is_coherent(buf)) > + return; > + > if (!sgt) > return; > > + /* For both USERPTR and non-coherent MMAP */ > dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir); > + > + /* Non-coherrent MMAP only */ Same typo. > + if (!vb2_dc_is_coherent(buf) && buf->vaddr) > + invalidate_kernel_vmap_range(buf->vaddr, buf->size); > } > > /*********************************************/ > /* callbacks for MMAP buffers */ > /*********************************************/ > > +static void __vb2_dc_put(struct vb2_dc_buf *buf) > +{ > + if (vb2_dc_is_coherent(buf)) { > + dma_free_attrs(buf->dev, buf->size, buf->cookie, > + buf->dma_addr, buf->attrs); > + return; > + } > + > + if (buf->vaddr) > + dma_vunmap_noncontiguous(buf->dev, buf->vaddr); > + dma_free_noncontiguous(buf->dev, buf->size, > + buf->dma_sgt, buf->dma_addr); > +} > + > static void vb2_dc_put(void *buf_priv) > { > struct vb2_dc_buf *buf = buf_priv; > @@ -139,17 +195,47 @@ static void vb2_dc_put(void *buf_priv) > sg_free_table(buf->sgt_base); > kfree(buf->sgt_base); > } > - dma_free_attrs(buf->dev, buf->size, buf->cookie, buf->dma_addr, > - buf->attrs); > + __vb2_dc_put(buf); > put_device(buf->dev); > kfree(buf); > } > > +static int vb2_dc_alloc_coherent(struct vb2_dc_buf *buf) > +{ > + struct vb2_queue *q = buf->vb->vb2_queue; > + > + buf->cookie = dma_alloc_attrs(buf->dev, > + buf->size, > + &buf->dma_addr, > + GFP_KERNEL | q->gfp_flags, > + buf->attrs); > + if (!buf->cookie) > + return -ENOMEM; > + if ((q->dma_attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0) > + buf->vaddr = buf->cookie; > + return 0; > +} > + > +static int vb2_dc_alloc_non_coherent(struct vb2_dc_buf *buf) > +{ > + struct vb2_queue *q = buf->vb->vb2_queue; > + > + buf->dma_sgt = dma_alloc_noncontiguous(buf->dev, > + buf->size, > + buf->dma_dir, > + GFP_KERNEL | q->gfp_flags, > + buf->attrs); > + if (!buf->dma_sgt) > + return -ENOMEM; DMA_ATTR_NO_KERNEL_MAPPING makes no sense here? If so, then it would be good to document that here. > + return 0; > +} > + > static void *vb2_dc_alloc(struct vb2_buffer *vb, > struct device *dev, > unsigned long size) > { > struct vb2_dc_buf *buf; > + int ret; > > if (WARN_ON(!dev)) > return ERR_PTR(-EINVAL); > @@ -159,27 +245,28 @@ static void *vb2_dc_alloc(struct vb2_buffer *vb, > return ERR_PTR(-ENOMEM); > > buf->attrs = vb->vb2_queue->dma_attrs; > - buf->cookie = dma_alloc_attrs(dev, size, &buf->dma_addr, > - GFP_KERNEL | vb->vb2_queue->gfp_flags, > - buf->attrs); > - if (!buf->cookie) { > - dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size); > - kfree(buf); > - return ERR_PTR(-ENOMEM); > - } > - > - if ((buf->attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0) > - buf->vaddr = buf->cookie; > + buf->dma_dir = vb->vb2_queue->dma_dir; > + buf->vb = vb; > + buf->non_coherent_mem = vb->vb2_queue->non_coherent_mem; > > + buf->size = size; > /* Prevent the device from being released while the buffer is used */ > buf->dev = get_device(dev); > - buf->size = size; > - buf->dma_dir = vb->vb2_queue->dma_dir; > + > + if (vb2_dc_is_coherent(buf)) > + ret = vb2_dc_alloc_coherent(buf); > + else > + ret = vb2_dc_alloc_non_coherent(buf); > + > + if (ret) { > + dev_err(dev, "dma alloc of size %ld failed\n", size); > + kfree(buf); > + return ERR_PTR(-ENOMEM); > + } > > buf->handler.refcount = &buf->refcount; > buf->handler.put = vb2_dc_put; > buf->handler.arg = buf; > - buf->vb = vb; > > refcount_set(&buf->refcount, 1); > > @@ -196,9 +283,12 @@ static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) > return -EINVAL; > } > > - ret = dma_mmap_attrs(buf->dev, vma, buf->cookie, > - buf->dma_addr, buf->size, buf->attrs); > - > + if (vb2_dc_is_coherent(buf)) > + ret = dma_mmap_attrs(buf->dev, vma, buf->cookie, buf->dma_addr, > + buf->size, buf->attrs); > + else > + ret = dma_mmap_noncontiguous(buf->dev, vma, buf->size, > + buf->dma_sgt); > if (ret) { > pr_err("Remapping memory failed, error: %d\n", ret); > return ret; > @@ -390,6 +480,9 @@ static struct sg_table *vb2_dc_get_base_sgt(struct vb2_dc_buf *buf) > int ret; > struct sg_table *sgt; > > + if (!vb2_dc_is_coherent(buf)) > + return buf->dma_sgt; > + > sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); > if (!sgt) { > dev_err(buf->dev, "failed to alloc sg table\n"); > Regards, Hans
On Tue, Mar 02, 2021 at 09:46:24AM +0900, Sergey Senozhatsky wrote: > This adds support for new noncontiguous DMA API, which > requires allocators to have two execution branches: one > for the current API, and one for the new one. > > Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> > [hch: untested conversion to the ne API] > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > .../common/videobuf2/videobuf2-dma-contig.c | 141 +++++++++++++++--- > 1 file changed, 117 insertions(+), 24 deletions(-) > > diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c > index 1e218bc440c6..d6a9f7b682f3 100644 > --- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c > +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c > @@ -17,6 +17,7 @@ > #include <linux/sched.h> > #include <linux/slab.h> > #include <linux/dma-mapping.h> > +#include <linux/highmem.h> > > #include <media/videobuf2-v4l2.h> > #include <media/videobuf2-dma-contig.h> > @@ -42,8 +43,14 @@ struct vb2_dc_buf { > struct dma_buf_attachment *db_attach; > > struct vb2_buffer *vb; > + unsigned int non_coherent_mem:1; > }; > > +static bool vb2_dc_is_coherent(struct vb2_dc_buf *buf) > +{ > + return !buf->non_coherent_mem; > +} nit: Given that this is just a simple negated return, do we need a dedicated helper for it? > + > /*********************************************/ > /* scatterlist table functions */ > /*********************************************/ > @@ -78,12 +85,21 @@ static void *vb2_dc_cookie(struct vb2_buffer *vb, void *buf_priv) > static void *vb2_dc_vaddr(struct vb2_buffer *vb, void *buf_priv) > { > struct vb2_dc_buf *buf = buf_priv; > - struct dma_buf_map map; > - int ret; > > - if (!buf->vaddr && buf->db_attach) { > - ret = dma_buf_vmap(buf->db_attach->dmabuf, &map); > - buf->vaddr = ret ? NULL : map.vaddr; > + if (buf->vaddr) > + return buf->vaddr; > + > + if (buf->db_attach) { > + struct dma_buf_map map; > + > + if (!dma_buf_vmap(buf->db_attach->dmabuf, &map)) > + buf->vaddr = map.vaddr; > + } > + > + if (!vb2_dc_is_coherent(buf)) { I believe it's not possible for both buf->db_attach and !vb2_dc_is_coherent() to be true, but nevertheless the code can be misleading for the reader. Would it make sense to just return early in the if that handles db_attach? > + buf->vaddr = dma_vmap_noncontiguous(buf->dev, > + buf->size, > + buf->dma_sgt); > } > > return buf->vaddr; > @@ -101,13 +117,26 @@ static void vb2_dc_prepare(void *buf_priv) > struct vb2_dc_buf *buf = buf_priv; > struct sg_table *sgt = buf->dma_sgt; > > + /* This takes care of DMABUF and user-enforced cache sync hint */ > if (buf->vb->skip_cache_sync_on_prepare) > return; > > + /* > + * Coherent MMAP buffers do not need to be synced, unlike coherent > + * USERPTR and non-coherent MMAP buffers. USERPTR buffers are always considered non-coherent. > + */ > + if (buf->vb->memory == V4L2_MEMORY_MMAP && vb2_dc_is_coherent(buf)) > + return; > + > if (!sgt) > return; > > + /* For both USERPTR and non-coherent MMAP */ > dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir); > + > + /* Non-coherrent MMAP only */ > + if (!vb2_dc_is_coherent(buf) && buf->vaddr) > + flush_kernel_vmap_range(buf->vaddr, buf->size); > } > > static void vb2_dc_finish(void *buf_priv) > @@ -115,19 +144,46 @@ static void vb2_dc_finish(void *buf_priv) > struct vb2_dc_buf *buf = buf_priv; > struct sg_table *sgt = buf->dma_sgt; > > + /* This takes care of DMABUF and user-enforced cache sync hint */ > if (buf->vb->skip_cache_sync_on_finish) > return; > > + /* > + * Coherent MMAP buffers do not need to be synced, unlike coherent > + * USERPTR and non-coherent MMAP buffers. Ditto. > + */ > + if (buf->vb->memory == V4L2_MEMORY_MMAP && vb2_dc_is_coherent(buf)) > + return; > + > if (!sgt) > return; > > + /* For both USERPTR and non-coherent MMAP */ > dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir); > + > + /* Non-coherrent MMAP only */ > + if (!vb2_dc_is_coherent(buf) && buf->vaddr) > + invalidate_kernel_vmap_range(buf->vaddr, buf->size); > } > > /*********************************************/ > /* callbacks for MMAP buffers */ > /*********************************************/ > > +static void __vb2_dc_put(struct vb2_dc_buf *buf) > +{ > + if (vb2_dc_is_coherent(buf)) { > + dma_free_attrs(buf->dev, buf->size, buf->cookie, > + buf->dma_addr, buf->attrs); > + return; > + } > + > + if (buf->vaddr) > + dma_vunmap_noncontiguous(buf->dev, buf->vaddr); > + dma_free_noncontiguous(buf->dev, buf->size, > + buf->dma_sgt, buf->dma_addr); > +} > + > static void vb2_dc_put(void *buf_priv) nit: Unrelated to this patch or series, but could be a follow-up clean-up: Could we rename this and the newly added function to include mmap in the name, since it's only for MMAP buffers? Best regards, Tomasz
diff --git a/drivers/media/common/videobuf2/videobuf2-dma-contig.c b/drivers/media/common/videobuf2/videobuf2-dma-contig.c index 1e218bc440c6..d6a9f7b682f3 100644 --- a/drivers/media/common/videobuf2/videobuf2-dma-contig.c +++ b/drivers/media/common/videobuf2/videobuf2-dma-contig.c @@ -17,6 +17,7 @@ #include <linux/sched.h> #include <linux/slab.h> #include <linux/dma-mapping.h> +#include <linux/highmem.h> #include <media/videobuf2-v4l2.h> #include <media/videobuf2-dma-contig.h> @@ -42,8 +43,14 @@ struct vb2_dc_buf { struct dma_buf_attachment *db_attach; struct vb2_buffer *vb; + unsigned int non_coherent_mem:1; }; +static bool vb2_dc_is_coherent(struct vb2_dc_buf *buf) +{ + return !buf->non_coherent_mem; +} + /*********************************************/ /* scatterlist table functions */ /*********************************************/ @@ -78,12 +85,21 @@ static void *vb2_dc_cookie(struct vb2_buffer *vb, void *buf_priv) static void *vb2_dc_vaddr(struct vb2_buffer *vb, void *buf_priv) { struct vb2_dc_buf *buf = buf_priv; - struct dma_buf_map map; - int ret; - if (!buf->vaddr && buf->db_attach) { - ret = dma_buf_vmap(buf->db_attach->dmabuf, &map); - buf->vaddr = ret ? NULL : map.vaddr; + if (buf->vaddr) + return buf->vaddr; + + if (buf->db_attach) { + struct dma_buf_map map; + + if (!dma_buf_vmap(buf->db_attach->dmabuf, &map)) + buf->vaddr = map.vaddr; + } + + if (!vb2_dc_is_coherent(buf)) { + buf->vaddr = dma_vmap_noncontiguous(buf->dev, + buf->size, + buf->dma_sgt); } return buf->vaddr; @@ -101,13 +117,26 @@ static void vb2_dc_prepare(void *buf_priv) struct vb2_dc_buf *buf = buf_priv; struct sg_table *sgt = buf->dma_sgt; + /* This takes care of DMABUF and user-enforced cache sync hint */ if (buf->vb->skip_cache_sync_on_prepare) return; + /* + * Coherent MMAP buffers do not need to be synced, unlike coherent + * USERPTR and non-coherent MMAP buffers. + */ + if (buf->vb->memory == V4L2_MEMORY_MMAP && vb2_dc_is_coherent(buf)) + return; + if (!sgt) return; + /* For both USERPTR and non-coherent MMAP */ dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir); + + /* Non-coherrent MMAP only */ + if (!vb2_dc_is_coherent(buf) && buf->vaddr) + flush_kernel_vmap_range(buf->vaddr, buf->size); } static void vb2_dc_finish(void *buf_priv) @@ -115,19 +144,46 @@ static void vb2_dc_finish(void *buf_priv) struct vb2_dc_buf *buf = buf_priv; struct sg_table *sgt = buf->dma_sgt; + /* This takes care of DMABUF and user-enforced cache sync hint */ if (buf->vb->skip_cache_sync_on_finish) return; + /* + * Coherent MMAP buffers do not need to be synced, unlike coherent + * USERPTR and non-coherent MMAP buffers. + */ + if (buf->vb->memory == V4L2_MEMORY_MMAP && vb2_dc_is_coherent(buf)) + return; + if (!sgt) return; + /* For both USERPTR and non-coherent MMAP */ dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir); + + /* Non-coherrent MMAP only */ + if (!vb2_dc_is_coherent(buf) && buf->vaddr) + invalidate_kernel_vmap_range(buf->vaddr, buf->size); } /*********************************************/ /* callbacks for MMAP buffers */ /*********************************************/ +static void __vb2_dc_put(struct vb2_dc_buf *buf) +{ + if (vb2_dc_is_coherent(buf)) { + dma_free_attrs(buf->dev, buf->size, buf->cookie, + buf->dma_addr, buf->attrs); + return; + } + + if (buf->vaddr) + dma_vunmap_noncontiguous(buf->dev, buf->vaddr); + dma_free_noncontiguous(buf->dev, buf->size, + buf->dma_sgt, buf->dma_addr); +} + static void vb2_dc_put(void *buf_priv) { struct vb2_dc_buf *buf = buf_priv; @@ -139,17 +195,47 @@ static void vb2_dc_put(void *buf_priv) sg_free_table(buf->sgt_base); kfree(buf->sgt_base); } - dma_free_attrs(buf->dev, buf->size, buf->cookie, buf->dma_addr, - buf->attrs); + __vb2_dc_put(buf); put_device(buf->dev); kfree(buf); } +static int vb2_dc_alloc_coherent(struct vb2_dc_buf *buf) +{ + struct vb2_queue *q = buf->vb->vb2_queue; + + buf->cookie = dma_alloc_attrs(buf->dev, + buf->size, + &buf->dma_addr, + GFP_KERNEL | q->gfp_flags, + buf->attrs); + if (!buf->cookie) + return -ENOMEM; + if ((q->dma_attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0) + buf->vaddr = buf->cookie; + return 0; +} + +static int vb2_dc_alloc_non_coherent(struct vb2_dc_buf *buf) +{ + struct vb2_queue *q = buf->vb->vb2_queue; + + buf->dma_sgt = dma_alloc_noncontiguous(buf->dev, + buf->size, + buf->dma_dir, + GFP_KERNEL | q->gfp_flags, + buf->attrs); + if (!buf->dma_sgt) + return -ENOMEM; + return 0; +} + static void *vb2_dc_alloc(struct vb2_buffer *vb, struct device *dev, unsigned long size) { struct vb2_dc_buf *buf; + int ret; if (WARN_ON(!dev)) return ERR_PTR(-EINVAL); @@ -159,27 +245,28 @@ static void *vb2_dc_alloc(struct vb2_buffer *vb, return ERR_PTR(-ENOMEM); buf->attrs = vb->vb2_queue->dma_attrs; - buf->cookie = dma_alloc_attrs(dev, size, &buf->dma_addr, - GFP_KERNEL | vb->vb2_queue->gfp_flags, - buf->attrs); - if (!buf->cookie) { - dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size); - kfree(buf); - return ERR_PTR(-ENOMEM); - } - - if ((buf->attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0) - buf->vaddr = buf->cookie; + buf->dma_dir = vb->vb2_queue->dma_dir; + buf->vb = vb; + buf->non_coherent_mem = vb->vb2_queue->non_coherent_mem; + buf->size = size; /* Prevent the device from being released while the buffer is used */ buf->dev = get_device(dev); - buf->size = size; - buf->dma_dir = vb->vb2_queue->dma_dir; + + if (vb2_dc_is_coherent(buf)) + ret = vb2_dc_alloc_coherent(buf); + else + ret = vb2_dc_alloc_non_coherent(buf); + + if (ret) { + dev_err(dev, "dma alloc of size %ld failed\n", size); + kfree(buf); + return ERR_PTR(-ENOMEM); + } buf->handler.refcount = &buf->refcount; buf->handler.put = vb2_dc_put; buf->handler.arg = buf; - buf->vb = vb; refcount_set(&buf->refcount, 1); @@ -196,9 +283,12 @@ static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) return -EINVAL; } - ret = dma_mmap_attrs(buf->dev, vma, buf->cookie, - buf->dma_addr, buf->size, buf->attrs); - + if (vb2_dc_is_coherent(buf)) + ret = dma_mmap_attrs(buf->dev, vma, buf->cookie, buf->dma_addr, + buf->size, buf->attrs); + else + ret = dma_mmap_noncontiguous(buf->dev, vma, buf->size, + buf->dma_sgt); if (ret) { pr_err("Remapping memory failed, error: %d\n", ret); return ret; @@ -390,6 +480,9 @@ static struct sg_table *vb2_dc_get_base_sgt(struct vb2_dc_buf *buf) int ret; struct sg_table *sgt; + if (!vb2_dc_is_coherent(buf)) + return buf->dma_sgt; + sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) { dev_err(buf->dev, "failed to alloc sg table\n");