Lines Matching refs:memory
14 particular user pointer method (not only memory mapping) is supported
16 with the memory type set to ``V4L2_MEMORY_USERPTR``.
18 This I/O method combines advantages of the read/write and memory mapping
20 can reside for example in virtual or shared memory. Only pointers to
39 reqbuf.memory = V4L2_MEMORY_USERPTR;
54 driver swaps memory pages within physical memory to create a continuous
55 area of memory. This happens transparently to the application in the
56 virtual memory subsystem of the kernel. When buffer pages have been
58 memory for DMA. [#f1]_
62 memory pages at any time between the completion of the DMA and this
63 ioctl. The memory is also unlocked when
67 Firstly, the buffers remain locked for longer, wasting physical memory.
68 Secondly the driver will not be notified when the memory is returned to
113 memory usage drivers can limit the number of buffers locked in