diff options
| -rw-r--r-- | drivers/base/dma-buf.c | 34 | ||||
| -rw-r--r-- | include/linux/dma-buf.h | 14 |
2 files changed, 48 insertions, 0 deletions
diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c index 7cfb405b1ad..d43d80256fd 100644 --- a/drivers/base/dma-buf.c +++ b/drivers/base/dma-buf.c @@ -468,3 +468,37 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma, return dmabuf->ops->mmap(dmabuf, vma); } EXPORT_SYMBOL_GPL(dma_buf_mmap); + +/** + * dma_buf_vmap - Create virtual mapping for the buffer object into kernel address space. Same restrictions as for vmap and friends apply. + * @dma_buf: [in] buffer to vmap + * + * This call may fail due to lack of virtual mapping address space. + * These calls are optional in drivers. The intended use for them + * is for mapping objects linear in kernel space for high use objects. + * Please attempt to use kmap/kunmap before thinking about these interfaces. + */ +void *dma_buf_vmap(struct dma_buf *dmabuf) +{ + if (WARN_ON(!dmabuf)) + return NULL; + + if (dmabuf->ops->vmap) + return dmabuf->ops->vmap(dmabuf); + return NULL; +} +EXPORT_SYMBOL_GPL(dma_buf_vmap); + +/** + * dma_buf_vunmap - Unmap a vmap obtained by dma_buf_vmap. + * @dma_buf: [in] buffer to vmap + */ +void dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr) +{ + if (WARN_ON(!dmabuf)) + return; + + if (dmabuf->ops->vunmap) + dmabuf->ops->vunmap(dmabuf, vaddr); +} +EXPORT_SYMBOL_GPL(dma_buf_vunmap); diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 1f78d1594cc..a02b1ff6488 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -98,6 +98,9 @@ struct dma_buf_ops { void (*kunmap)(struct dma_buf *, unsigned long, void *); int (*mmap)(struct dma_buf *, struct vm_area_struct *vma); + + void *(*vmap)(struct dma_buf *); + void (*vunmap)(struct dma_buf *, void *vaddr); }; /** @@ -176,6 +179,8 @@ void dma_buf_kunmap(struct dma_buf *, unsigned long, void *); int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *, unsigned long); +void *dma_buf_vmap(struct dma_buf *); +void dma_buf_vunmap(struct dma_buf *, void *vaddr); #else static inline struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, @@ -264,6 +269,15 @@ static inline int dma_buf_mmap(struct dma_buf *dmabuf, { return -ENODEV; } + +static inline void *dma_buf_vmap(struct dma_buf *dmabuf) +{ + return NULL; +} + +static inline void dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr) +{ +} #endif /* CONFIG_DMA_SHARED_BUFFER */ #endif /* __DMA_BUF_H__ */ |