brcm2708: update to latest patches from RPi Foundation

[openwrt/staging/dedeckeh.git] / target / linux / brcm2708 / patches-4.19 / 950-0259-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch

diff --git a/target/linux/brcm2708/patches-4.19/950-0259-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch b/target/linux/brcm2708/patches-4.19/950-0259-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch
deleted file mode 100644 (file)
index 8bc1691..0000000
--- a/target/linux/brcm2708/patches-4.19/950-0259-media-vb2-Allow-reqbufs-0-with-in-use-MMAP-buffers.patch
+++ /dev/null
@@ -1,76 +0,0 @@
-From cf6f8129b6af78116e00b1d781e0bcc8c4b73890 Mon Sep 17 00:00:00 2001
-From: John Sheu <sheu@chromium.org>
-Date: Thu, 15 Oct 2015 18:05:25 +0900
-Subject: [PATCH] media: vb2: Allow reqbufs(0) with "in use" MMAP
- buffers
-
-Videobuf2 presently does not allow VIDIOC_REQBUFS to destroy outstanding
-buffers if the queue is of type V4L2_MEMORY_MMAP, and if the buffers are
-considered "in use".  This is different behavior than for other memory
-types and prevents us from deallocating buffers in following two cases:
-
-1) There are outstanding mmap()ed views on the buffer. However even if
-   we put the buffer in reqbufs(0), there will be remaining references,
-   due to vma .open/close() adjusting vb2 buffer refcount appropriately.
-   This means that the buffer will be in fact freed only when the last
-   mmap()ed view is unmapped.
-
-2) Buffer has been exported as a DMABUF. Refcount of the vb2 buffer
-   is managed properly by VB2 DMABUF ops, i.e. incremented on DMABUF
-   get and decremented on DMABUF release. This means that the buffer
-   will be alive until all importers release it.
-
-Considering both cases above, there does not seem to be any need to
-prevent reqbufs(0) operation, because buffer lifetime is already
-properly managed by both mmap() and DMABUF code paths. Let's remove it
-and allow userspace freeing the queue (and potentially allocating a new
-one) even though old buffers might be still in processing.
-
-Signed-off-by: John Sheu <sheu@chromium.org>
-Reviewed-by: Pawel Osciak <posciak@chromium.org>
-Reviewed-by: Tomasz Figa <tfiga@chromium.org>
-Signed-off-by: Tomasz Figa <tfiga@chromium.org>
----
- .../media/common/videobuf2/videobuf2-core.c   | 23 -------------------
- 1 file changed, 23 deletions(-)
-
---- a/drivers/media/common/videobuf2/videobuf2-core.c
-+++ b/drivers/media/common/videobuf2/videobuf2-core.c
-@@ -554,20 +554,6 @@ bool vb2_buffer_in_use(struct vb2_queue
- }
- EXPORT_SYMBOL(vb2_buffer_in_use);
- 
--/*
-- * __buffers_in_use() - return true if any buffers on the queue are in use and
-- * the queue cannot be freed (by the means of REQBUFS(0)) call
-- */
--static bool __buffers_in_use(struct vb2_queue *q)
--{
--      unsigned int buffer;
--      for (buffer = 0; buffer < q->num_buffers; ++buffer) {
--              if (vb2_buffer_in_use(q, q->bufs[buffer]))
--                      return true;
--      }
--      return false;
--}
--
- void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb)
- {
-       call_void_bufop(q, fill_user_buffer, q->bufs[index], pb);
-@@ -679,16 +665,7 @@ int vb2_core_reqbufs(struct vb2_queue *q
- 
-       if (*count == 0 || q->num_buffers != 0 ||
-           (q->memory != VB2_MEMORY_UNKNOWN && q->memory != memory)) {
--              /*
--               * We already have buffers allocated, so first check if they
--               * are not in use and can be freed.
--               */
-               mutex_lock(&q->mmap_lock);
--              if (q->memory == VB2_MEMORY_MMAP && __buffers_in_use(q)) {
--                      mutex_unlock(&q->mmap_lock);
--                      dprintk(1, "memory in use, cannot free\n");
--                      return -EBUSY;
--              }
- 
-               /*
-                * Call queue_cancel to clean up any buffers in the PREPARED or