1 files changed, 153 insertions, 26 deletions

diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 602b12d7470d..dd0f83ee505b 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -20,6 +20,7 @@
 #include <linux/debugfs.h>
 #include <linux/module.h>
 #include <linux/seq_file.h>
+#include <linux/sync_file.h>
 #include <linux/poll.h>
 #include <linux/dma-resv.h>
 #include <linux/mm.h>
@@ -52,7 +53,7 @@ static char *dmabuffs_dname(struct dentry *dentry, char *buffer, int buflen)
 		ret = strlcpy(name, dmabuf->name, DMA_BUF_NAME_LEN);
 	spin_unlock(&dmabuf->name_lock);
 
-	return dynamic_dname(dentry, buffer, buflen, "/%s:%s",
+	return dynamic_dname(buffer, buflen, "/%s:%s",
 			     dentry->d_name.name, ret > 0 ? name : "");
 }
 
@@ -192,6 +193,9 @@ static loff_t dma_buf_llseek(struct file *file, loff_t offset, int whence)
  * Note that this only signals the completion of the respective fences, i.e. the
  * DMA transfers are complete. Cache flushing and any other necessary
  * preparations before CPU access can begin still need to happen.
+ *
+ * As an alternative to poll(), the set of fences on DMA buffer can be
+ * exported as a &sync_file using &dma_buf_sync_file_export.
  */
 
 static void dma_buf_poll_cb(struct dma_fence *fence, struct dma_fence_cb *cb)
@@ -216,7 +220,8 @@ static bool dma_buf_poll_add_cb(struct dma_resv *resv, bool write,
 	struct dma_fence *fence;
 	int r;
 
-	dma_resv_for_each_fence(&cursor, resv, write, fence) {
+	dma_resv_for_each_fence(&cursor, resv, dma_resv_usage_rw(write),
+				fence) {
 		dma_fence_get(fence);
 		r = dma_fence_add_callback(fence, &dcb->cb, dma_buf_poll_cb);
 		if (!r)
@@ -325,6 +330,101 @@ static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf)
 	return 0;
 }
 
+#if IS_ENABLED(CONFIG_SYNC_FILE)
+static long dma_buf_export_sync_file(struct dma_buf *dmabuf,
+				     void __user *user_data)
+{
+	struct dma_buf_export_sync_file arg;
+	enum dma_resv_usage usage;
+	struct dma_fence *fence = NULL;
+	struct sync_file *sync_file;
+	int fd, ret;
+
+	if (copy_from_user(&arg, user_data, sizeof(arg)))
+		return -EFAULT;
+
+	if (arg.flags & ~DMA_BUF_SYNC_RW)
+		return -EINVAL;
+
+	if ((arg.flags & DMA_BUF_SYNC_RW) == 0)
+		return -EINVAL;
+
+	fd = get_unused_fd_flags(O_CLOEXEC);
+	if (fd < 0)
+		return fd;
+
+	usage = dma_resv_usage_rw(arg.flags & DMA_BUF_SYNC_WRITE);
+	ret = dma_resv_get_singleton(dmabuf->resv, usage, &fence);
+	if (ret)
+		goto err_put_fd;
+
+	if (!fence)
+		fence = dma_fence_get_stub();
+
+	sync_file = sync_file_create(fence);
+
+	dma_fence_put(fence);
+
+	if (!sync_file) {
+		ret = -ENOMEM;
+		goto err_put_fd;
+	}
+
+	arg.fd = fd;
+	if (copy_to_user(user_data, &arg, sizeof(arg))) {
+		ret = -EFAULT;
+		goto err_put_file;
+	}
+
+	fd_install(fd, sync_file->file);
+
+	return 0;
+
+err_put_file:
+	fput(sync_file->file);
+err_put_fd:
+	put_unused_fd(fd);
+	return ret;
+}
+
+static long dma_buf_import_sync_file(struct dma_buf *dmabuf,
+				     const void __user *user_data)
+{
+	struct dma_buf_import_sync_file arg;
+	struct dma_fence *fence;
+	enum dma_resv_usage usage;
+	int ret = 0;
+
+	if (copy_from_user(&arg, user_data, sizeof(arg)))
+		return -EFAULT;
+
+	if (arg.flags & ~DMA_BUF_SYNC_RW)
+		return -EINVAL;
+
+	if ((arg.flags & DMA_BUF_SYNC_RW) == 0)
+		return -EINVAL;
+
+	fence = sync_file_get_fence(arg.fd);
+	if (!fence)
+		return -EINVAL;
+
+	usage = (arg.flags & DMA_BUF_SYNC_WRITE) ? DMA_RESV_USAGE_WRITE :
+						   DMA_RESV_USAGE_READ;
+
+	dma_resv_lock(dmabuf->resv, NULL);
+
+	ret = dma_resv_reserve_fences(dmabuf->resv, 1);
+	if (!ret)
+		dma_resv_add_fence(dmabuf->resv, fence, usage);
+
+	dma_resv_unlock(dmabuf->resv);
+
+	dma_fence_put(fence);
+
+	return ret;
+}
+#endif
+
 static long dma_buf_ioctl(struct file *file,
 			  unsigned int cmd, unsigned long arg)
 {
@@ -368,6 +468,13 @@ static long dma_buf_ioctl(struct file *file,
 	case DMA_BUF_SET_NAME_B:
 		return dma_buf_set_name(dmabuf, (const char __user *)arg);
 
+#if IS_ENABLED(CONFIG_SYNC_FILE)
+	case DMA_BUF_IOCTL_EXPORT_SYNC_FILE:
+		return dma_buf_export_sync_file(dmabuf, (void __user *)arg);
+	case DMA_BUF_IOCTL_IMPORT_SYNC_FILE:
+		return dma_buf_import_sync_file(dmabuf, (const void __user *)arg);
+#endif
+
 	default:
 		return -ENOTTY;
 	}
@@ -407,6 +514,7 @@ static inline int is_dma_buf_file(struct file *file)
 
 static struct file *dma_buf_getfile(struct dma_buf *dmabuf, int flags)
 {
+	static atomic64_t dmabuf_inode = ATOMIC64_INIT(0);
 	struct file *file;
 	struct inode *inode = alloc_anon_inode(dma_buf_mnt->mnt_sb);
 
@@ -416,11 +524,18 @@ static struct file *dma_buf_getfile(struct dma_buf *dmabuf, int flags)
 	inode->i_size = dmabuf->size;
 	inode_set_bytes(inode, dmabuf->size);
 
+	/*
+	 * The ->i_ino acquired from get_next_ino() is not unique thus
+	 * not suitable for using it as dentry name by dmabuf stats.
+	 * Override ->i_ino with the unique and dmabuffs specific
+	 * value.
+	 */
+	inode->i_ino = atomic64_add_return(1, &dmabuf_inode);
+	flags &= O_ACCMODE | O_NONBLOCK;
 	file = alloc_file_pseudo(inode, dma_buf_mnt, "dmabuf",
 				 flags, &dma_buf_fops);
 	if (IS_ERR(file))
 		goto err_alloc_file;
-	file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
 	file->private_data = dmabuf;
 	file->f_path.dentry->d_fsdata = dmabuf;
 
@@ -443,7 +558,7 @@ err_alloc_file:
  *    as a file descriptor by calling dma_buf_fd().
  *
  * 2. Userspace passes this file-descriptors to all drivers it wants this buffer
- *    to share with: First the filedescriptor is converted to a &dma_buf using
+ *    to share with: First the file descriptor is converted to a &dma_buf using
  *    dma_buf_get(). Then the buffer is attached to the device using
  *    dma_buf_attach().
  *
@@ -540,13 +655,8 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
 		goto err_dmabuf;
 	}
 
-	file->f_mode |= FMODE_LSEEK;
 	dmabuf->file = file;
 
-	ret = dma_buf_stats_setup(dmabuf);
-	if (ret)
-		goto err_sysfs;
-
 	mutex_init(&dmabuf->lock);
 	INIT_LIST_HEAD(&dmabuf->attachments);
 
@@ -554,6 +664,10 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
 	list_add(&dmabuf->list_node, &db_list.head);
 	mutex_unlock(&db_list.lock);
 
+	ret = dma_buf_stats_setup(dmabuf);
+	if (ret)
+		goto err_sysfs;
+
 	return dmabuf;
 
 err_sysfs:
@@ -660,12 +774,24 @@ static struct sg_table * __map_dma_buf(struct dma_buf_attachment *attach,
 				       enum dma_data_direction direction)
 {
 	struct sg_table *sg_table;
+	signed long ret;
 
 	sg_table = attach->dmabuf->ops->map_dma_buf(attach, direction);
+	if (IS_ERR_OR_NULL(sg_table))
+		return sg_table;
+
+	if (!dma_buf_attachment_is_dynamic(attach)) {
+		ret = dma_resv_wait_timeout(attach->dmabuf->resv,
+					    DMA_RESV_USAGE_KERNEL, true,
+					    MAX_SCHEDULE_TIMEOUT);
+		if (ret < 0) {
+			attach->dmabuf->ops->unmap_dma_buf(attach, sg_table,
+							   direction);
+			return ERR_PTR(ret);
+		}
+	}
 
-	if (!IS_ERR_OR_NULL(sg_table))
-		mangle_sg_table(sg_table);
-
+	mangle_sg_table(sg_table);
 	return sg_table;
 }
 
@@ -1047,8 +1173,8 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_move_notify, DMA_BUF);
  *
  *   Interfaces::
  *
- *      void \*dma_buf_vmap(struct dma_buf \*dmabuf, struct dma_buf_map \*map)
- *      void dma_buf_vunmap(struct dma_buf \*dmabuf, struct dma_buf_map \*map)
+ *      void \*dma_buf_vmap(struct dma_buf \*dmabuf, struct iosys_map \*map)
+ *      void dma_buf_vunmap(struct dma_buf \*dmabuf, struct iosys_map \*map)
  *
  *   The vmap call can fail if there is no vmap support in the exporter, or if
  *   it runs out of vmalloc space. Note that the dma-buf layer keeps a reference
@@ -1124,7 +1250,8 @@ static int __dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
 	long ret;
 
 	/* Wait on any implicit rendering fences */
-	ret = dma_resv_wait_timeout(resv, write, true, MAX_SCHEDULE_TIMEOUT);
+	ret = dma_resv_wait_timeout(resv, dma_resv_usage_rw(write),
+				    true, MAX_SCHEDULE_TIMEOUT);
 	if (ret < 0)
 		return ret;
 
@@ -1260,12 +1387,12 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_mmap, DMA_BUF);
  *
  * Returns 0 on success, or a negative errno code otherwise.
  */
-int dma_buf_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
-	struct dma_buf_map ptr;
+	struct iosys_map ptr;
 	int ret = 0;
 
-	dma_buf_map_clear(map);
+	iosys_map_clear(map);
 
 	if (WARN_ON(!dmabuf))
 		return -EINVAL;
@@ -1276,12 +1403,12 @@ int dma_buf_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
 	mutex_lock(&dmabuf->lock);
 	if (dmabuf->vmapping_counter) {
 		dmabuf->vmapping_counter++;
-		BUG_ON(dma_buf_map_is_null(&dmabuf->vmap_ptr));
+		BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr));
 		*map = dmabuf->vmap_ptr;
 		goto out_unlock;
 	}
 
-	BUG_ON(dma_buf_map_is_set(&dmabuf->vmap_ptr));
+	BUG_ON(iosys_map_is_set(&dmabuf->vmap_ptr));
 
 	ret = dmabuf->ops->vmap(dmabuf, &ptr);
 	if (WARN_ON_ONCE(ret))
@@ -1303,20 +1430,20 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_vmap, DMA_BUF);
  * @dmabuf:	[in]	buffer to vunmap
  * @map:	[in]	vmap pointer to vunmap
  */
-void dma_buf_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map)
+void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map)
 {
 	if (WARN_ON(!dmabuf))
 		return;
 
-	BUG_ON(dma_buf_map_is_null(&dmabuf->vmap_ptr));
+	BUG_ON(iosys_map_is_null(&dmabuf->vmap_ptr));
 	BUG_ON(dmabuf->vmapping_counter == 0);
-	BUG_ON(!dma_buf_map_is_equal(&dmabuf->vmap_ptr, map));
+	BUG_ON(!iosys_map_is_equal(&dmabuf->vmap_ptr, map));
 
 	mutex_lock(&dmabuf->lock);
 	if (--dmabuf->vmapping_counter == 0) {
 		if (dmabuf->ops->vunmap)
 			dmabuf->ops->vunmap(dmabuf, map);
-		dma_buf_map_clear(&dmabuf->vmap_ptr);
+		iosys_map_clear(&dmabuf->vmap_ptr);
 	}
 	mutex_unlock(&dmabuf->lock);
 }
@@ -1337,7 +1464,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
 		return ret;
 
 	seq_puts(s, "\nDma-buf Objects:\n");
-	seq_printf(s, "%-8s\t%-8s\t%-8s\t%-8s\texp_name\t%-8s\n",
+	seq_printf(s, "%-8s\t%-8s\t%-8s\t%-8s\texp_name\t%-8s\tname\n",
 		   "size", "flags", "mode", "count", "ino");
 
 	list_for_each_entry(buf_obj, &db_list.head, list_node) {
@@ -1354,7 +1481,7 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
 				file_count(buf_obj->file),
 				buf_obj->exp_name,
 				file_inode(buf_obj->file)->i_ino,
-				buf_obj->name ?: "");
+				buf_obj->name ?: "<none>");
 		spin_unlock(&buf_obj->name_lock);
 
 		dma_resv_describe(buf_obj->resv, s);