drm/msm: Unblock writer if reader closes file
authorKristian H. Kristensen <hoegsberg@gmail.com>
Wed, 19 Dec 2018 16:57:41 +0000 (08:57 -0800)
committerRob Clark <robdclark@gmail.com>
Wed, 19 Dec 2018 19:43:25 +0000 (14:43 -0500)
Prevents deadlock when fifo is full and reader closes file.

Signed-off-by: Kristian H. Kristensen <hoegsberg@chromium.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
drivers/gpu/drm/msm/msm_rd.c

index b567206..d990b5f 100644 (file)
@@ -115,7 +115,9 @@ static void rd_write(struct msm_rd_state *rd, const void *buf, int sz)
                char *fptr = &fifo->buf[fifo->head];
                int n;
 
-               wait_event(rd->fifo_event, circ_space(&rd->fifo) > 0);
+               wait_event(rd->fifo_event, circ_space(&rd->fifo) > 0 || !rd->open);
+               if (!rd->open)
+                       return;
 
                /* Note that smp_load_acquire() is not strictly required
                 * as CIRC_SPACE_TO_END() does not access the tail more
@@ -213,7 +215,10 @@ out:
 static int rd_release(struct inode *inode, struct file *file)
 {
        struct msm_rd_state *rd = inode->i_private;
+
        rd->open = false;
+       wake_up_all(&rd->fifo_event);
+
        return 0;
 }