Modify the framework to adapt to more map modes, add benchmark
support for dma_map_sg, and add support sg map mode in ioctl.

The result:
[root@localhost]# ./dma_map_benchmark -m 1 -g 8 -t 8 -s 30 -d 2
dma mapping mode: DMA_MAP_SG_MODE
dma mapping benchmark: threads:8 seconds:30 node:-1 dir:FROM_DEVICE granule/sg_nents: 8
average map latency(us):1.4 standard deviation:0.3
average unmap latency(us):1.3 standard deviation:0.3
[root@localhost]# ./dma_map_benchmark -m 0 -g 8 -t 8 -s 30 -d 2
dma mapping mode: DMA_MAP_SINGLE_MODE
dma mapping benchmark: threads:8 seconds:30 node:-1 dir:FROM_DEVICE granule/sg_nents: 8
average map latency(us):1.0 standard deviation:0.3
average unmap latency(us):1.3 standard deviation:0.5

---
Qinxin Xia (3):
  dma-mapping: benchmark: modify the framework to adapt to more map
    modes
  dma-mapping: benchmark: add support for dma_map_sg
  dma-mapping benchmark:add support for dma_map_sg

 include/linux/map_benchmark.h                 |   7 +
 kernel/dma/map_benchmark.c                    | 224 ++++++++++++++++--
 .../testing/selftests/dma/dma_map_benchmark.c |  16 +-
 3 files changed, 222 insertions(+), 25 deletions(-)

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2.33.0