15 files changed, 152 insertions, 63 deletions

diff --git a/Documentation/dma-buf-sharing.txt b/Documentation/dma-buf-sharing.txt
index bb9753b635a3..480c8de3c2c4 100644
--- a/Documentation/dma-buf-sharing.txt
+++ b/Documentation/dma-buf-sharing.txt
@@ -49,25 +49,26 @@ The dma_buf buffer sharing API usage contains the following steps:
    The buffer exporter announces its wish to export a buffer. In this, it
    connects its own private buffer data, provides implementation for operations
    that can be performed on the exported dma_buf, and flags for the file
-   associated with this buffer.
+   associated with this buffer. All these fields are filled in struct
+   dma_buf_export_info, defined via the DEFINE_DMA_BUF_EXPORT_INFO macro.
 
    Interface:
-      struct dma_buf *dma_buf_export_named(void *priv, struct dma_buf_ops *ops,
-                                     size_t size, int flags,
-                                     const char *exp_name)
+      DEFINE_DMA_BUF_EXPORT_INFO(exp_info)
+      struct dma_buf *dma_buf_export(struct dma_buf_export_info *exp_info)
 
-   If this succeeds, dma_buf_export_named allocates a dma_buf structure, and
+   If this succeeds, dma_buf_export allocates a dma_buf structure, and
    returns a pointer to the same. It also associates an anonymous file with this
    buffer, so it can be exported. On failure to allocate the dma_buf object,
    it returns NULL.
 
-   'exp_name' is the name of exporter - to facilitate information while
-   debugging.
+   'exp_name' in struct dma_buf_export_info is the name of exporter - to
+   facilitate information while debugging. It is set to KBUILD_MODNAME by
+   default, so exporters don't have to provide a specific name, if they don't
+   wish to.
+
+   DEFINE_DMA_BUF_EXPORT_INFO macro defines the struct dma_buf_export_info,
+   zeroes it out and pre-populates exp_name in it.
 
-   Exporting modules which do not wish to provide any specific name may use the
-   helper define 'dma_buf_export()', with the same arguments as above, but
-   without the last argument; a KBUILD_MODNAME pre-processor directive will be
-   inserted in place of 'exp_name' instead.
 
 2. Userspace gets a handle to pass around to potential buffer-users
 
diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 5be225c2ba98..c5a9138a6a8d 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -265,43 +265,40 @@ static inline int is_dma_buf_file(struct file *file)
 }
 
 /**
- * dma_buf_export_named - Creates a new dma_buf, and associates an anon file
+ * dma_buf_export - Creates a new dma_buf, and associates an anon file
  * with this buffer, so it can be exported.
  * Also connect the allocator specific data and ops to the buffer.
  * Additionally, provide a name string for exporter; useful in debugging.
  *
- * @priv:       [in]    Attach private data of allocator to this buffer
- * @ops:        [in]    Attach allocator-defined dma buf ops to the new buffer.
- * @size:       [in]    Size of the buffer
- * @flags:      [in]    mode flags for the file.
- * @exp_name:   [in]    name of the exporting module - useful for debugging.
- * @resv:       [in]    reservation-object, NULL to allocate default one.
+ * @exp_info:   [in]    holds all the export related information provided
+ *                      by the exporter. see struct dma_buf_export_info
+ *                      for further details.
  *
  * Returns, on success, a newly created dma_buf object, which wraps the
  * supplied private data and operations for dma_buf_ops. On either missing
  * ops, or error in allocating struct dma_buf, will return negative error.
  *
  */
-struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops,
-                                size_t size, int flags, const char *exp_name,
-                                struct reservation_object *resv)
+struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
 {
         struct dma_buf *dmabuf;
+        struct reservation_object *resv = exp_info->resv;
         struct file *file;
         size_t alloc_size = sizeof(struct dma_buf);
-        if (!resv)
+        if (!exp_info->resv)
                 alloc_size += sizeof(struct reservation_object);
         else
                 /* prevent &dma_buf[1] == dma_buf->resv */
                 alloc_size += 1;
 
-        if (WARN_ON(!priv || !ops
-                          || !ops->map_dma_buf
-                          || !ops->unmap_dma_buf
-                          || !ops->release
-                          || !ops->kmap_atomic
-                          || !ops->kmap
-                          || !ops->mmap)) {
+        if (WARN_ON(!exp_info->priv
+                          || !exp_info->ops
+                          || !exp_info->ops->map_dma_buf
+                          || !exp_info->ops->unmap_dma_buf
+                          || !exp_info->ops->release
+                          || !exp_info->ops->kmap_atomic
+                          || !exp_info->ops->kmap
+                          || !exp_info->ops->mmap)) {
                 return ERR_PTR(-EINVAL);
         }
 
@@ -309,10 +306,10 @@ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops,
         if (dmabuf == NULL)
                 return ERR_PTR(-ENOMEM);
 
-        dmabuf->priv = priv;
-        dmabuf->ops = ops;
-        dmabuf->size = size;
-        dmabuf->exp_name = exp_name;
+        dmabuf->priv = exp_info->priv;
+        dmabuf->ops = exp_info->ops;
+        dmabuf->size = exp_info->size;
+        dmabuf->exp_name = exp_info->exp_name;
         init_waitqueue_head(&dmabuf->poll);
         dmabuf->cb_excl.poll = dmabuf->cb_shared.poll = &dmabuf->poll;
         dmabuf->cb_excl.active = dmabuf->cb_shared.active = 0;
@@ -323,7 +320,8 @@ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops,
         }
         dmabuf->resv = resv;
 
-        file = anon_inode_getfile("dmabuf", &dma_buf_fops, dmabuf, flags);
+        file = anon_inode_getfile("dmabuf", &dma_buf_fops, dmabuf,
+                                        exp_info->flags);
         if (IS_ERR(file)) {
                 kfree(dmabuf);
                 return ERR_CAST(file);
@@ -341,8 +339,7 @@ struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops,
 
         return dmabuf;
 }
-EXPORT_SYMBOL_GPL(dma_buf_export_named);
-
+EXPORT_SYMBOL_GPL(dma_buf_export);
 
 /**
  * dma_buf_fd - returns a file descriptor for the given dma_buf
diff --git a/drivers/gpu/drm/armada/armada_gem.c b/drivers/gpu/drm/armada/armada_gem.c
index ef5feeecec84..580e10acaa3a 100644
--- a/drivers/gpu/drm/armada/armada_gem.c
+++ b/drivers/gpu/drm/armada/armada_gem.c
@@ -538,8 +538,14 @@ struct dma_buf *
 armada_gem_prime_export(struct drm_device *dev, struct drm_gem_object *obj,
         int flags)
 {
-        return dma_buf_export(obj, &armada_gem_prime_dmabuf_ops, obj->size,
-                              O_RDWR, NULL);
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &armada_gem_prime_dmabuf_ops;
+        exp_info.size = obj->size;
+        exp_info.flags = O_RDWR;
+        exp_info.priv = obj;
+
+        return dma_buf_export(&exp_info);
 }
 
 struct drm_gem_object *
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 7482b06cd08f..7fec191b45f7 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -339,13 +339,17 @@ static const struct dma_buf_ops drm_gem_prime_dmabuf_ops =  {
 struct dma_buf *drm_gem_prime_export(struct drm_device *dev,
                                      struct drm_gem_object *obj, int flags)
 {
-        struct reservation_object *robj = NULL;
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &drm_gem_prime_dmabuf_ops;
+        exp_info.size = obj->size;
+        exp_info.flags = flags;
+        exp_info.priv = obj;
 
         if (dev->driver->gem_prime_res_obj)
-                robj = dev->driver->gem_prime_res_obj(obj);
+                exp_info.resv = dev->driver->gem_prime_res_obj(obj);
 
-        return dma_buf_export(obj, &drm_gem_prime_dmabuf_ops, obj->size,
-                              flags, robj);
+        return dma_buf_export(&exp_info);
 }
 EXPORT_SYMBOL(drm_gem_prime_export);
 
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
index 3833bf8ca025..cd485c091b30 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
@@ -185,9 +185,14 @@ struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev,
                                 struct drm_gem_object *obj, int flags)
 {
         struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 
-        return dma_buf_export(obj, &exynos_dmabuf_ops,
-                                exynos_gem_obj->base.size, flags, NULL);
+        exp_info.ops = &exynos_dmabuf_ops;
+        exp_info.size = exynos_gem_obj->base.size;
+        exp_info.flags = flags;
+        exp_info.priv = obj;
+
+        return dma_buf_export(&exp_info);
 }
 
 struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
index 82a1f4b57778..7998da27c500 100644
--- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
@@ -230,6 +230,13 @@ struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
                                       struct drm_gem_object *gem_obj, int flags)
 {
         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &i915_dmabuf_ops;
+        exp_info.size = gem_obj->size;
+        exp_info.flags = flags;
+        exp_info.priv = gem_obj;
+
 
         if (obj->ops->dmabuf_export) {
                 int ret = obj->ops->dmabuf_export(obj);
@@ -237,8 +244,7 @@ struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
                         return ERR_PTR(ret);
         }
 
-        return dma_buf_export(gem_obj, &i915_dmabuf_ops, gem_obj->size, flags,
-                              NULL);
+        return dma_buf_export(&exp_info);
 }
 
 static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
diff --git a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
index b46dabd9faf7..344fd789170d 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
@@ -171,7 +171,14 @@ static struct dma_buf_ops omap_dmabuf_ops = {
 struct dma_buf *omap_gem_prime_export(struct drm_device *dev,
                 struct drm_gem_object *obj, int flags)
 {
-        return dma_buf_export(obj, &omap_dmabuf_ops, obj->size, flags, NULL);
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &omap_dmabuf_ops;
+        exp_info.size = obj->size;
+        exp_info.flags = flags;
+        exp_info.priv = obj;
+
+        return dma_buf_export(&exp_info);
 }
 
 struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev,
diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index cfb481943b6b..1217272a51f2 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -627,8 +627,14 @@ struct dma_buf *tegra_gem_prime_export(struct drm_device *drm,
                                        struct drm_gem_object *gem,
                                        int flags)
 {
-        return dma_buf_export(gem, &tegra_gem_prime_dmabuf_ops, gem->size,
-                              flags, NULL);
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &tegra_gem_prime_dmabuf_ops;
+        exp_info.size = gem->size;
+        exp_info.flags = flags;
+        exp_info.priv = gem;
+
+        return dma_buf_export(&exp_info);
 }
 
 struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,
diff --git a/drivers/gpu/drm/ttm/ttm_object.c b/drivers/gpu/drm/ttm/ttm_object.c
index 12c87110db3a..4f5fa8d65fe9 100644
--- a/drivers/gpu/drm/ttm/ttm_object.c
+++ b/drivers/gpu/drm/ttm/ttm_object.c
@@ -683,6 +683,12 @@ int ttm_prime_handle_to_fd(struct ttm_object_file *tfile,
 
         dma_buf = prime->dma_buf;
         if (!dma_buf || !get_dma_buf_unless_doomed(dma_buf)) {
+                DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+                exp_info.ops = &tdev->ops;
+                exp_info.size = prime->size;
+                exp_info.flags = flags;
+                exp_info.priv = prime;
 
                 /*
                  * Need to create a new dma_buf, with memory accounting.
@@ -694,8 +700,7 @@ int ttm_prime_handle_to_fd(struct ttm_object_file *tfile,
                         goto out_unref;
                 }
 
-                dma_buf = dma_buf_export(prime, &tdev->ops,
-                                         prime->size, flags, NULL);
+                dma_buf = dma_buf_export(&exp_info);
                 if (IS_ERR(dma_buf)) {
                         ret = PTR_ERR(dma_buf);
                         ttm_mem_global_free(tdev->mem_glob,
diff --git a/drivers/gpu/drm/udl/udl_dmabuf.c b/drivers/gpu/drm/udl/udl_dmabuf.c
index ac8a66b4dfc2..e2243edd1ce3 100644
--- a/drivers/gpu/drm/udl/udl_dmabuf.c
+++ b/drivers/gpu/drm/udl/udl_dmabuf.c
@@ -202,7 +202,14 @@ static struct dma_buf_ops udl_dmabuf_ops = {
 struct dma_buf *udl_gem_prime_export(struct drm_device *dev,
                                      struct drm_gem_object *obj, int flags)
 {
-        return dma_buf_export(obj, &udl_dmabuf_ops, obj->size, flags, NULL);
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &udl_dmabuf_ops;
+        exp_info.size = obj->size;
+        exp_info.flags = flags;
+        exp_info.priv = obj;
+
+        return dma_buf_export(&exp_info);
 }
 
 static int udl_prime_create(struct drm_device *dev,
diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c
index 69e0483adfee..644dec73d220 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-contig.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c
@@ -402,6 +402,12 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags)
 {
         struct vb2_dc_buf *buf = buf_priv;
         struct dma_buf *dbuf;
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &vb2_dc_dmabuf_ops;
+        exp_info.size = buf->size;
+        exp_info.flags = flags;
+        exp_info.priv = buf;
 
         if (!buf->sgt_base)
                 buf->sgt_base = vb2_dc_get_base_sgt(buf);
@@ -409,7 +415,7 @@ static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv, unsigned long flags)
         if (WARN_ON(!buf->sgt_base))
                 return NULL;
 
-        dbuf = dma_buf_export(buf, &vb2_dc_dmabuf_ops, buf->size, flags, NULL);
+        dbuf = dma_buf_export(&exp_info);
         if (IS_ERR(dbuf))
                 return NULL;
 
diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c
index b1838abb6d00..45c708e463b9 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
@@ -583,11 +583,17 @@ static struct dma_buf *vb2_dma_sg_get_dmabuf(void *buf_priv, unsigned long flags
 {
         struct vb2_dma_sg_buf *buf = buf_priv;
         struct dma_buf *dbuf;
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &vb2_dma_sg_dmabuf_ops;
+        exp_info.size = buf->size;
+        exp_info.flags = flags;
+        exp_info.priv = buf;
 
         if (WARN_ON(!buf->dma_sgt))
                 return NULL;
 
-        dbuf = dma_buf_export(buf, &vb2_dma_sg_dmabuf_ops, buf->size, flags, NULL);
+        dbuf = dma_buf_export(&exp_info);
         if (IS_ERR(dbuf))
                 return NULL;
 
diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c
index bcde88572429..657ab302a5cf 100644
--- a/drivers/media/v4l2-core/videobuf2-vmalloc.c
+++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c
@@ -368,11 +368,17 @@ static struct dma_buf *vb2_vmalloc_get_dmabuf(void *buf_priv, unsigned long flag
 {
         struct vb2_vmalloc_buf *buf = buf_priv;
         struct dma_buf *dbuf;
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &vb2_vmalloc_dmabuf_ops;
+        exp_info.size = buf->size;
+        exp_info.flags = flags;
+        exp_info.priv = buf;
 
         if (WARN_ON(!buf->vaddr))
                 return NULL;
 
-        dbuf = dma_buf_export(buf, &vb2_vmalloc_dmabuf_ops, buf->size, flags, NULL);
+        dbuf = dma_buf_export(&exp_info);
         if (IS_ERR(dbuf))
                 return NULL;
 
diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index 0e3d8c7add24..b94d69feff46 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -1106,6 +1106,12 @@ struct dma_buf *ion_share_dma_buf(struct ion_client *client,
         struct ion_buffer *buffer;
         struct dma_buf *dmabuf;
         bool valid_handle;
+        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+        exp_info.ops = &dma_buf_ops;
+        exp_info.size = buffer->size;
+        exp_info.flags = O_RDWR;
+        exp_info.priv = buffer;
 
         mutex_lock(&client->lock);
         valid_handle = ion_handle_validate(client, handle);
@@ -1118,8 +1124,7 @@ struct dma_buf *ion_share_dma_buf(struct ion_client *client,
         ion_buffer_get(buffer);
         mutex_unlock(&client->lock);
 
-        dmabuf = dma_buf_export(buffer, &dma_buf_ops, buffer->size, O_RDWR,
-                                NULL);
+        dmabuf = dma_buf_export(&exp_info);
         if (IS_ERR(dmabuf)) {
                 ion_buffer_put(buffer);
                 return dmabuf;
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index 694e1fe1c4b4..2f0b431b73e0 100644
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -163,6 +163,33 @@ struct dma_buf_attachment {
 };
 
 /**
+ * struct dma_buf_export_info - holds information needed to export a dma_buf
+ * @exp_name:   name of the exporting module - useful for debugging.
+ * @ops:        Attach allocator-defined dma buf ops to the new buffer
+ * @size:       Size of the buffer
+ * @flags:      mode flags for the file
+ * @resv:       reservation-object, NULL to allocate default one
+ * @priv:       Attach private data of allocator to this buffer
+ *
+ * This structure holds the information required to export the buffer. Used
+ * with dma_buf_export() only.
+ */
+struct dma_buf_export_info {
+        const char *exp_name;
+        const struct dma_buf_ops *ops;
+        size_t size;
+        int flags;
+        struct reservation_object *resv;
+        void *priv;
+};
+
+/**
+ * helper macro for exporters; zeros and fills in most common values
+ */
+#define DEFINE_DMA_BUF_EXPORT_INFO(a)   \
+        struct dma_buf_export_info a = { .exp_name = KBUILD_MODNAME }
+
+/**
  * get_dma_buf - convenience wrapper for get_file.
  * @dmabuf:     [in]    pointer to dma_buf
  *
@@ -181,12 +208,7 @@ struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf,
 void dma_buf_detach(struct dma_buf *dmabuf,
                                 struct dma_buf_attachment *dmabuf_attach);
 
-struct dma_buf *dma_buf_export_named(void *priv, const struct dma_buf_ops *ops,
-                               size_t size, int flags, const char *,
-                               struct reservation_object *);
-
-#define dma_buf_export(priv, ops, size, flags, resv)    \
-        dma_buf_export_named(priv, ops, size, flags, KBUILD_MODNAME, resv)
+struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info);
 
 int dma_buf_fd(struct dma_buf *dmabuf, int flags);
 struct dma_buf *dma_buf_get(int fd);