diff options
Diffstat (limited to 'drivers/media/v4l2-core/videobuf2-vmalloc.c')
| -rw-r--r-- | drivers/media/v4l2-core/videobuf2-vmalloc.c | 194 |
1 files changed, 184 insertions, 10 deletions
diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c index 313d9771b2bc..fba944e50227 100644 --- a/drivers/media/v4l2-core/videobuf2-vmalloc.c +++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c @@ -25,7 +25,7 @@ struct vb2_vmalloc_buf { void *vaddr; struct page **pages; struct vm_area_struct *vma; - int write; + enum dma_data_direction dma_dir; unsigned long size; unsigned int n_pages; atomic_t refcount; @@ -35,7 +35,8 @@ struct vb2_vmalloc_buf { static void vb2_vmalloc_put(void *buf_priv); -static void *vb2_vmalloc_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_flags) +static void *vb2_vmalloc_alloc(void *alloc_ctx, unsigned long size, + enum dma_data_direction dma_dir, gfp_t gfp_flags) { struct vb2_vmalloc_buf *buf; @@ -45,6 +46,7 @@ static void *vb2_vmalloc_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_fl buf->size = size; buf->vaddr = vmalloc_user(buf->size); + buf->dma_dir = dma_dir; buf->handler.refcount = &buf->refcount; buf->handler.put = vb2_vmalloc_put; buf->handler.arg = buf; @@ -70,7 +72,8 @@ static void vb2_vmalloc_put(void *buf_priv) } static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr, - unsigned long size, int write) + unsigned long size, + enum dma_data_direction dma_dir) { struct vb2_vmalloc_buf *buf; unsigned long first, last; @@ -82,7 +85,7 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr, if (!buf) return NULL; - buf->write = write; + buf->dma_dir = dma_dir; offset = vaddr & ~PAGE_MASK; buf->size = size; @@ -107,7 +110,8 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr, /* current->mm->mmap_sem is taken by videobuf2 core */ n_pages = get_user_pages(current, current->mm, vaddr & PAGE_MASK, buf->n_pages, - write, 1, /* force */ + dma_dir == DMA_FROM_DEVICE, + 1, /* force */ buf->pages, NULL); if (n_pages != buf->n_pages) goto fail_get_user_pages; @@ -144,14 +148,13 @@ static void vb2_vmalloc_put_userptr(void *buf_priv) if (vaddr) vm_unmap_ram((void *)vaddr, buf->n_pages); for (i = 0; i < buf->n_pages; ++i) { - if (buf->write) + if (buf->dma_dir == DMA_FROM_DEVICE) set_page_dirty_lock(buf->pages[i]); put_page(buf->pages[i]); } kfree(buf->pages); } else { - if (buf->vma) - vb2_put_vma(buf->vma); + vb2_put_vma(buf->vma); iounmap(buf->vaddr); } kfree(buf); @@ -209,6 +212,176 @@ static int vb2_vmalloc_mmap(void *buf_priv, struct vm_area_struct *vma) } /*********************************************/ +/* DMABUF ops for exporters */ +/*********************************************/ + +struct vb2_vmalloc_attachment { + struct sg_table sgt; + enum dma_data_direction dma_dir; +}; + +static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev, + struct dma_buf_attachment *dbuf_attach) +{ + struct vb2_vmalloc_attachment *attach; + struct vb2_vmalloc_buf *buf = dbuf->priv; + int num_pages = PAGE_ALIGN(buf->size) / PAGE_SIZE; + struct sg_table *sgt; + struct scatterlist *sg; + void *vaddr = buf->vaddr; + int ret; + int i; + + attach = kzalloc(sizeof(*attach), GFP_KERNEL); + if (!attach) + return -ENOMEM; + + sgt = &attach->sgt; + ret = sg_alloc_table(sgt, num_pages, GFP_KERNEL); + if (ret) { + kfree(attach); + return ret; + } + for_each_sg(sgt->sgl, sg, sgt->nents, i) { + struct page *page = vmalloc_to_page(vaddr); + + if (!page) { + sg_free_table(sgt); + kfree(attach); + return -ENOMEM; + } + sg_set_page(sg, page, PAGE_SIZE, 0); + vaddr += PAGE_SIZE; + } + + attach->dma_dir = DMA_NONE; + dbuf_attach->priv = attach; + return 0; +} + +static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf *dbuf, + struct dma_buf_attachment *db_attach) +{ + struct vb2_vmalloc_attachment *attach = db_attach->priv; + struct sg_table *sgt; + + if (!attach) + return; + + sgt = &attach->sgt; + + /* release the scatterlist cache */ + if (attach->dma_dir != DMA_NONE) + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dma_dir); + sg_free_table(sgt); + kfree(attach); + db_attach->priv = NULL; +} + +static struct sg_table *vb2_vmalloc_dmabuf_ops_map( + struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir) +{ + struct vb2_vmalloc_attachment *attach = db_attach->priv; + /* stealing dmabuf mutex to serialize map/unmap operations */ + struct mutex *lock = &db_attach->dmabuf->lock; + struct sg_table *sgt; + int ret; + + mutex_lock(lock); + + sgt = &attach->sgt; + /* return previously mapped sg table */ + if (attach->dma_dir == dma_dir) { + mutex_unlock(lock); + return sgt; + } + + /* release any previous cache */ + if (attach->dma_dir != DMA_NONE) { + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dma_dir); + attach->dma_dir = DMA_NONE; + } + + /* mapping to the client with new direction */ + ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dma_dir); + if (ret <= 0) { + pr_err("failed to map scatterlist\n"); + mutex_unlock(lock); + return ERR_PTR(-EIO); + } + + attach->dma_dir = dma_dir; + + mutex_unlock(lock); + + return sgt; +} + +static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach, + struct sg_table *sgt, enum dma_data_direction dma_dir) +{ + /* nothing to be done here */ +} + +static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf *dbuf) +{ + /* drop reference obtained in vb2_vmalloc_get_dmabuf */ + vb2_vmalloc_put(dbuf->priv); +} + +static void *vb2_vmalloc_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum) +{ + struct vb2_vmalloc_buf *buf = dbuf->priv; + + return buf->vaddr + pgnum * PAGE_SIZE; +} + +static void *vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf *dbuf) +{ + struct vb2_vmalloc_buf *buf = dbuf->priv; + + return buf->vaddr; +} + +static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf *dbuf, + struct vm_area_struct *vma) +{ + return vb2_vmalloc_mmap(dbuf->priv, vma); +} + +static struct dma_buf_ops vb2_vmalloc_dmabuf_ops = { + .attach = vb2_vmalloc_dmabuf_ops_attach, + .detach = vb2_vmalloc_dmabuf_ops_detach, + .map_dma_buf = vb2_vmalloc_dmabuf_ops_map, + .unmap_dma_buf = vb2_vmalloc_dmabuf_ops_unmap, + .kmap = vb2_vmalloc_dmabuf_ops_kmap, + .kmap_atomic = vb2_vmalloc_dmabuf_ops_kmap, + .vmap = vb2_vmalloc_dmabuf_ops_vmap, + .mmap = vb2_vmalloc_dmabuf_ops_mmap, + .release = vb2_vmalloc_dmabuf_ops_release, +}; + +static struct dma_buf *vb2_vmalloc_get_dmabuf(void *buf_priv, unsigned long flags) +{ + struct vb2_vmalloc_buf *buf = buf_priv; + struct dma_buf *dbuf; + + if (WARN_ON(!buf->vaddr)) + return NULL; + + dbuf = dma_buf_export(buf, &vb2_vmalloc_dmabuf_ops, buf->size, flags, NULL); + if (IS_ERR(dbuf)) + return NULL; + + /* dmabuf keeps reference to vb2 buffer */ + atomic_inc(&buf->refcount); + + return dbuf; +} + +/*********************************************/ /* callbacks for DMABUF buffers */ /*********************************************/ @@ -240,7 +413,7 @@ static void vb2_vmalloc_detach_dmabuf(void *mem_priv) } static void *vb2_vmalloc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf, - unsigned long size, int write) + unsigned long size, enum dma_data_direction dma_dir) { struct vb2_vmalloc_buf *buf; @@ -252,7 +425,7 @@ static void *vb2_vmalloc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf, return ERR_PTR(-ENOMEM); buf->dbuf = dbuf; - buf->write = write; + buf->dma_dir = dma_dir; buf->size = size; return buf; @@ -264,6 +437,7 @@ const struct vb2_mem_ops vb2_vmalloc_memops = { .put = vb2_vmalloc_put, .get_userptr = vb2_vmalloc_get_userptr, .put_userptr = vb2_vmalloc_put_userptr, + .get_dmabuf = vb2_vmalloc_get_dmabuf, .map_dmabuf = vb2_vmalloc_map_dmabuf, .unmap_dmabuf = vb2_vmalloc_unmap_dmabuf, .attach_dmabuf = vb2_vmalloc_attach_dmabuf, |