drm/msm: Unblock writer if reader closes file

[ Upstream commit 99c66bc051e7407fe0bf0607b142ec0be1a1d1dd ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/msm/msm_rd.c b/drivers/gpu/drm/msm/msm_rd.c
index 9a78c48817c6a46e7baf181a87cd737d88abdd70..909a52b21ebe78100e3c4d6996c65628e96b1fb4 100644 (file)
--- a/drivers/gpu/drm/msm/msm_rd.c
+++ b/drivers/gpu/drm/msm/msm_rd.c
@@ -103,7 +103,9 @@ 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;
 
                n = min(sz, circ_space_to_end(&rd->fifo));
                memcpy(fptr, ptr, n);
@@ -192,7 +194,10 @@ 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;
 }