@@ -48,8 +48,24 @@ struct dma_buf_list {
static struct dma_buf_list db_list;
+static char *dmabuffs_dname(struct dentry *dentry, char *buffer, int buflen)
+{
+ struct dma_buf *dmabuf;
+ char name[DMA_BUF_NAME_LEN];
+ size_t ret = 0;
+
+ dmabuf = dentry->d_fsdata;
+ mutex_lock(&dmabuf->lock);
+ if (dmabuf->name)
+ ret = strlcpy(name, dmabuf->name, DMA_BUF_NAME_LEN);
+ mutex_unlock(&dmabuf->lock);
+
+ return dynamic_dname(dentry, buffer, buflen, "/%s:%s",
+ dentry->d_name.name, ret > 0 ? name : "");
+}
+
static const struct dentry_operations dma_buf_dentry_ops = {
- .d_dname = simple_dname,
+ .d_dname = dmabuffs_dname,
};
static struct vfsmount *dma_buf_mnt;
@@ -297,6 +313,27 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll)
return events;
}
+static long dma_buf_set_name(struct dma_buf *dmabuf, const char __user *buf)
+{
+ char *name = strndup_user(buf, DMA_BUF_NAME_LEN);
+ long ret = 0;
+
+ if (IS_ERR(name))
+ return PTR_ERR(name);
+
+ mutex_lock(&dmabuf->lock);
+ if (!list_empty(&dmabuf->attachments)) {
+ ret = -EBUSY;
+ goto out_unlock;
+ }
+ kfree(dmabuf->name);
+ dmabuf->name = name;
+
+out_unlock:
+ mutex_unlock(&dmabuf->lock);
+ return ret;
+}
+
static long dma_buf_ioctl(struct file *file,
unsigned int cmd, unsigned long arg)
{
@@ -335,6 +372,10 @@ static long dma_buf_ioctl(struct file *file,
ret = dma_buf_begin_cpu_access(dmabuf, direction);
return ret;
+
+ case DMA_BUF_SET_NAME:
+ return dma_buf_set_name(dmabuf, (const char __user *)arg);
+
default:
return -ENOTTY;
}
@@ -376,6 +417,7 @@ static struct file *dma_buf_getfile(struct dma_buf *dmabuf, int flags)
goto err_alloc_file;
file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
file->private_data = dmabuf;
+ file->f_path.dentry->d_fsdata = dmabuf;
return file;
@@ -1082,12 +1124,13 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
continue;
}
- seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\t%08lu\n",
+ seq_printf(s, "%08zu\t%08x\t%08x\t%08ld\t%s\t%08lu\t%s\n",
buf_obj->size,
buf_obj->file->f_flags, buf_obj->file->f_mode,
file_count(buf_obj->file),
buf_obj->exp_name,
- file_inode(buf_obj->file)->i_ino);
+ file_inode(buf_obj->file)->i_ino,
+ buf_obj->name ?: "");
robj = buf_obj->resv;
while (true) {
@@ -255,10 +255,12 @@ struct dma_buf_ops {
* @file: file pointer used for sharing buffers across, and for refcounting.
* @attachments: list of dma_buf_attachment that denotes all devices attached.
* @ops: dma_buf_ops associated with this buffer object.
- * @lock: used internally to serialize list manipulation, attach/detach and vmap/unmap
+ * @lock: used internally to serialize list manipulation, attach/detach and
+ * vmap/unmap, and accesses to name
* @vmapping_counter: used internally to refcnt the vmaps
* @vmap_ptr: the current vmap ptr if vmapping_counter > 0
* @exp_name: name of the exporter; useful for debugging.
+ * @name: userspace-provided name; useful for accounting and debugging.
* @owner: pointer to exporter module; used for refcounting when exporter is a
* kernel module.
* @list_node: node for dma_buf accounting and debugging.
@@ -286,6 +288,7 @@ struct dma_buf {
unsigned vmapping_counter;
void *vmap_ptr;
const char *exp_name;
+ const char *name;
struct module *owner;
struct list_head list_node;
void *priv;
@@ -35,7 +35,10 @@ struct dma_buf_sync {
#define DMA_BUF_SYNC_VALID_FLAGS_MASK \
(DMA_BUF_SYNC_RW | DMA_BUF_SYNC_END)
+#define DMA_BUF_NAME_LEN 32
+
#define DMA_BUF_BASE 'b'
#define DMA_BUF_IOCTL_SYNC _IOW(DMA_BUF_BASE, 0, struct dma_buf_sync)
+#define DMA_BUF_SET_NAME _IOW(DMA_BUF_BASE, 1, const char *)
#endif