Revert "dmabuf-sync: add select system call support."

This reverts commit 4439a419906d4fe3d7e5093292bd2f4f4fbfc8c2.

3 files changed, 0 insertions, 71 deletions

diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c
index fa42c56b30d..3d2d12bd058 100644
--- a/drivers/base/dma-buf.c
+++ b/drivers/base/dma-buf.c
@@ -29,7 +29,6 @@
 #include <linux/export.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
-#include <linux/poll.h>
 #include <linux/dmabuf-sync.h>
 
 static inline int is_dma_buf_file(struct file *);
@@ -81,52 +80,6 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
 	return dmabuf->ops->mmap(dmabuf, vma);
 }
 
-static unsigned int dma_buf_poll(struct file *filp,
-					struct poll_table_struct *poll)
-{
-	struct dma_buf *dmabuf;
-	struct dmabuf_sync_reservation *robj;
-	int ret = 0;
-
-	if (!is_dma_buf_file(filp))
-		return POLLERR;
-
-	dmabuf = filp->private_data;
-	if (!dmabuf || !dmabuf->sync)
-		return POLLERR;
-
-	robj = dmabuf->sync;
-
-	mutex_lock(&robj->lock);
-
-	robj->polled = true;
-
-	/*
-	 * CPU or DMA access to this buffer has been completed, and
-	 * the blocked task has been waked up. Return poll event
-	 * so that the task can get out of select().
-	 */
-	if (robj->poll_event) {
-		robj->poll_event = false;
-		mutex_unlock(&robj->lock);
-		return POLLIN | POLLOUT;
-	}
-
-	/*
-	 * There is no anyone accessing this buffer so just return POLLERR.
-	 */
-	if (!robj->locked) {
-		mutex_unlock(&robj->lock);
-		return POLLERR;
-	}
-
-	poll_wait(filp, &robj->poll_wait, poll);
-
-	mutex_unlock(&robj->lock);
-
-	return ret;
-}
-
 static int dma_buf_lock(struct file *file, int cmd, struct file_lock *fl)
 {
 	struct dma_buf *dmabuf;
@@ -162,7 +115,6 @@ static int dma_buf_lock(struct file *file, int cmd, struct file_lock *fl)
 static const struct file_operations dma_buf_fops = {
 	.release	= dma_buf_release,
 	.mmap		= dma_buf_mmap_internal,
-	.poll		= dma_buf_poll,
 	.lock		= dma_buf_lock,
 };
 
diff --git a/drivers/base/dmabuf-sync.c b/drivers/base/dmabuf-sync.c
index dab5b32a833..abfd8e3f009 100644
--- a/drivers/base/dmabuf-sync.c
+++ b/drivers/base/dmabuf-sync.c
@@ -63,12 +63,6 @@ static void dmabuf_sync_timeout_worker(struct work_struct *work)
 			continue;
 		}
 
-		if (sobj->robj->polled) {
-			sobj->robj->poll_event = true;
-			sobj->robj->polled = false;
-			wake_up_interruptible(&sobj->robj->poll_wait);
-		}
-
 		if (atomic_add_unless(&sobj->robj->shared_cnt, -1, 1)) {
 			mutex_unlock(&sobj->robj->lock);
 			continue;
@@ -283,12 +277,6 @@ static void dmabuf_sync_unlock_objs(struct dmabuf_sync *sync,
 	list_for_each_entry(sobj, &sync->syncs, head) {
 		mutex_lock(&sobj->robj->lock);
 
-		if (sobj->robj->polled) {
-			sobj->robj->poll_event = true;
-			sobj->robj->polled = false;
-			wake_up_interruptible(&sobj->robj->poll_wait);
-		}
-
 		if (atomic_add_unless(&sobj->robj->shared_cnt, -1, 1)) {
 			mutex_unlock(&sobj->robj->lock);
 			continue;
@@ -636,12 +624,6 @@ void dmabuf_sync_single_unlock(struct dma_buf *dmabuf)
 
 	mutex_lock(&robj->lock);
 
-	if (robj->polled) {
-		robj->poll_event = true;
-		robj->polled = false;
-		wake_up_interruptible(&robj->poll_wait);
-	}
-
 	if (atomic_add_unless(&robj->shared_cnt, -1 , 1)) {
 		mutex_unlock(&robj->lock);
 		dma_buf_put(dmabuf);
diff --git a/include/linux/dmabuf-sync.h b/include/linux/dmabuf-sync.h
index 9a3afc4870a..d4dcf4f84cd 100644
--- a/include/linux/dmabuf-sync.h
+++ b/include/linux/dmabuf-sync.h
@@ -22,9 +22,6 @@ enum dmabuf_sync_status {
 struct dmabuf_sync_reservation {
 	struct ww_mutex		sync_lock;
 	struct mutex		lock;
-	wait_queue_head_t	poll_wait;
-	unsigned int		poll_event;
-	unsigned int		polled;
 	atomic_t		shared_cnt;
 	unsigned int		accessed_type;
 	unsigned int		locked;
@@ -94,8 +91,6 @@ static inline void dmabuf_sync_reservation_init(struct dma_buf *dmabuf)
 
 	mutex_init(&obj->lock);
 	atomic_set(&obj->shared_cnt, 1);
-
-	init_waitqueue_head(&obj->poll_wait);
 }
 
 static inline void dmabuf_sync_reservation_fini(struct dma_buf *dmabuf)