Error occur when build kernel driver with open_bdev_excl function,why?

Autonomous Machines Jetson & Embedded Systems Jetson Xavier NX
#1

I write a driver in kernel,which use open_bdev_excl function to read block device
but when i build my driver,there are some error,as follow:
: ERROR： implicit declaration of function ‘open_bdev_excl’; did you mean ‘open_exec’? [-Werror=implicit-function-declaration]
bdev = open_bdev_excl(PATH, NULL, NULL);
^~~~~~~~~~~~~~
open_exec
/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/nvidia/drivers/media/i2c/ar0233.c:1069:8: ERROR： assignment makes pointer from integer without a cast [-Werror=int-conversion]
bdev = open_bdev_excl(PATH, NULL, NULL);
^
/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/nvidia/drivers/media/i2c/ar0233.c:1076:8: ERROR： implicit declaration of function ‘__bread’; did you mean ‘vread’? [-Werror=implicit-function-declaration]
bh = __bread(bdev, j, block_size);
^~~~~~~
vread
/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/nvidia/drivers/media/i2c/ar0233.c:1076:6: ERROR： assignment makes pointer from integer without a cast [-Werror=int-conversion]
bh = __bread(bdev, j, block_size);
^
/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/nvidia/drivers/media/i2c/ar0233.c:1082:17: ERROR： dereferencing pointer to incomplete type ‘struct buffer_head’
p = (char *)(bh->b_data);
^~
/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/nvidia/drivers/media/i2c/ar0233.c:1091:3: ERROR： Implicit function declaration ‘brelse’ [-Werror=implicit-function-declaration]
brelse(bh);
^~~~~~
/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/nvidia/drivers/media/i2c/ar0233.c:1096:1: ERROR： Implicit function declaration‘close_bdev_excl’ [-Werror=implicit-function-declaration]
close_bdev_excl(bdev);
^~~~~~~~~~~~~~~
cc1：所有的警告都被当作是错误
…/scripts/Makefile.build:341: recipe for target ‘drivers/media/i2c/ar0233.o’ failed
make[4]: *** [drivers/media/i2c/ar0233.o] Error 1
…/scripts/Makefile.build:649: recipe for target ‘drivers/media/i2c’ failed
make[3]: *** [drivers/media/i2c] Error 2
make[3]: *** 正在等待未完成的任务…
…/scripts/Makefile.build:649: recipe for target ‘drivers/media’ failed
make[2]: *** [drivers/media] Error 2
make[2]: *** 正在等待未完成的任务…
/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/kernel-4.9/Makefile:1104: recipe for target ‘drivers’ failed
make[1]: *** [drivers] Error 2
make[1]: 离开目录“/home/autel-lee/dolphin_project/git/optimus-kernel/kernel/kernel-4.9/build”
Makefile:171: recipe for target ‘sub-make’ failed
make: *** [sub-make] Error 2

I check my kernel is kernel 4.9, is this function(open_bdev_excl) available in current kernel version?

#3

Looks like didn’t include correct include file.

#4

I searched this in 4.9.10 kernel source code,but i didn’t find it

#5

Why need this API for a sensor driver? You may change an API that include in the kernel.

#6

i need API for disk partition read/write in kernel space,because i set a specified partition ,and write a config yaml file to this partition with dd command in user space.i want to read this config yaml file in my kernel driver.

#7

OK, you may need to make sure this API have include in the kernel space otherwise you may need other solution.

#9