CHROMIUM: dma-buf/kds: allow KDS to be compiled out if dma-buf is enabled

[cascardo/linux.git] / include / linux / dma-buf.h

diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index 3efbfc2..5eb40e7 100644 (file)
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -30,6 +30,10 @@
 #include <linux/list.h>
 #include <linux/dma-mapping.h>
 #include <linux/fs.h>
+#ifdef CONFIG_DMA_SHARED_BUFFER_USES_KDS
+#include <linux/kds.h>
+#include <linux/wait.h>
+#endif
 
 struct device;
 struct dma_buf;
@@ -61,6 +65,13 @@ struct dma_buf_attachment;
  *                This Callback must not sleep.
  * @kmap: maps a page from the buffer into kernel address space.
  * @kunmap: [optional] unmaps a page from the buffer.
+ * @mmap: used to expose the backing storage to userspace. Note that the
+ *       mapping needs to be coherent - if the exporter doesn't directly
+ *       support this, it needs to fake coherency by shooting down any ptes
+ *       when transitioning away from the cpu domain.
+ * @vmap: [optional] creates a virtual mapping for the buffer into kernel
+ *       address space. Same restrictions as for vmap and friends apply.
+ * @vunmap: [optional] unmaps a vmap from the buffer
  */
 struct dma_buf_ops {
        int (*attach)(struct dma_buf *, struct device *,
@@ -92,6 +103,11 @@ struct dma_buf_ops {
        void (*kunmap_atomic)(struct dma_buf *, unsigned long, void *);
        void *(*kmap)(struct dma_buf *, unsigned long);
        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);
 };
 
 /**
@@ -109,6 +125,12 @@ struct dma_buf {
        const struct dma_buf_ops *ops;
        /* mutex to serialize list manipulation and attach/detach */
        struct mutex lock;
+#ifdef CONFIG_DMA_SHARED_BUFFER_USES_KDS
+       struct kds_resource kds;
+       wait_queue_head_t wq_exclusive;
+       wait_queue_head_t wq_shared;
+       struct kds_callback kds_cb;
+#endif
        void *priv;
 };
 
@@ -144,6 +166,23 @@ static inline void get_dma_buf(struct dma_buf *dmabuf)
        get_file(dmabuf->file);
 }
 
+#ifdef CONFIG_DMA_SHARED_BUFFER_USES_KDS
+/**
+ * get_dma_buf_kds_resource - get a KDS resource for this dma-buf
+ * @dmabuf:    [in]    pointer to dma_buf
+ *
+ * Returns a KDS resource that represents the dma-buf. This should be used by
+ * drivers to synchronize access to the buffer. Note that the caller should
+ * ensure that a reference to the dma-buf exists from the call to
+ * kds_async_wait until kds_resource_set_release is called.
+ */
+static inline struct kds_resource *
+       get_dma_buf_kds_resource(struct dma_buf *dmabuf)
+{
+       return &dmabuf->kds;
+}
+#endif
+
 #ifdef CONFIG_DMA_SHARED_BUFFER
 struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf,
                                                        struct device *dev);
@@ -167,6 +206,11 @@ void *dma_buf_kmap_atomic(struct dma_buf *, unsigned long);
 void dma_buf_kunmap_atomic(struct dma_buf *, unsigned long, void *);
 void *dma_buf_kmap(struct dma_buf *, unsigned long);
 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,
@@ -248,6 +292,22 @@ static inline void dma_buf_kunmap(struct dma_buf *dmabuf,
                                  unsigned long pnum, void *vaddr)
 {
 }
+
+static inline int dma_buf_mmap(struct dma_buf *dmabuf,
+                              struct vm_area_struct *vma,
+                              unsigned long pgoff)
+{
+       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__ */