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

---
Changes since V3:
- Address the comments from Barry, change mode to a more specific namespace.
- Link: https://lore.kernel.org/all/20250509020238.3378396-1-xiaqinxin@huawei.com/

Changes since V2:
- Address the comments from Barry and ALOK, some commit information and function
  input parameter names are modified to make them more accurate.
- Link: https://lore.kernel.org/all/20250506030100.394376-1-xiaqinxin@huawei.com/

Changes since V1:
- Address the comments from Barry, added some comments and changed the unmap type to void.
- Link: https://lore.kernel.org/lkml/20250212022718.1995504-1-xiaqinxin@huawei.com/


Qinxin Xia (4):
  dma-mapping: benchmark: Add padding to ensure uABI remained consistent
  dma-mapping: benchmark: modify the framework to adapt to more map
    modes
  dma-mapping: benchmark: add support for dma_map_sg
  selftests/dma: Add dma_map_sg support for dma_map_benchmark

 include/linux/map_benchmark.h                 |  46 +++-
 kernel/dma/map_benchmark.c                    | 225 ++++++++++++++++--
 .../testing/selftests/dma/dma_map_benchmark.c |  16 +-
 3 files changed, 252 insertions(+), 35 deletions(-)

-- 
2.33.0