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include: linux: Update kernel headers to version v5.16-rc7

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Updated kernel headers to v5.16-rc7 using
utils/update-kernel-headers.sh and re-instating libcamera
local modifications.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
This commit is contained in:
David Plowman 2022-01-05 15:55:37 +00:00 • committed by Laurent Pinchart
parent d769a59566
commit aa45336399
8 changed files with 625 additions and 40 deletions
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50
include/linux/dma-buf.h
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@ -22,8 +22,56 @@
#include <linux/types.h>
/* begin/end dma-buf functions used for userspace mmap. */
/**
* struct dma_buf_sync - Synchronize with CPU access.
*
* When a DMA buffer is accessed from the CPU via mmap, it is not always
* possible to guarantee coherency between the CPU-visible map and underlying
* memory. To manage coherency, DMA_BUF_IOCTL_SYNC must be used to bracket
* any CPU access to give the kernel the chance to shuffle memory around if
* needed.
*
* Prior to accessing the map, the client must call DMA_BUF_IOCTL_SYNC
* with DMA_BUF_SYNC_START and the appropriate read/write flags. Once the
* access is complete, the client should call DMA_BUF_IOCTL_SYNC with
* DMA_BUF_SYNC_END and the same read/write flags.
*
* The synchronization provided via DMA_BUF_IOCTL_SYNC only provides cache
* coherency. It does not prevent other processes or devices from
* accessing the memory at the same time. If synchronization with a GPU or
* other device driver is required, it is the client's responsibility to
* wait for buffer to be ready for reading or writing before calling this
* ioctl with DMA_BUF_SYNC_START. Likewise, the client must ensure that
* follow-up work is not submitted to GPU or other device driver until
* after this ioctl has been called with DMA_BUF_SYNC_END?
*
* If the driver or API with which the client is interacting uses implicit
* synchronization, waiting for prior work to complete can be done via
* poll() on the DMA buffer file descriptor. If the driver or API requires
* explicit synchronization, the client may have to wait on a sync_file or
* other synchronization primitive outside the scope of the DMA buffer API.
*/
struct dma_buf_sync {
/**
* @flags: Set of access flags
*
* DMA_BUF_SYNC_START:
* Indicates the start of a map access session.
*
* DMA_BUF_SYNC_END:
* Indicates the end of a map access session.
*
* DMA_BUF_SYNC_READ:
* Indicates that the mapped DMA buffer will be read by the
* client via the CPU map.
*
* DMA_BUF_SYNC_WRITE:
* Indicates that the mapped DMA buffer will be written by the
* client via the CPU map.
*
* DMA_BUF_SYNC_RW:
* An alias for DMA_BUF_SYNC_READ | DMA_BUF_SYNC_WRITE.
*/
__u64 flags;
};