How to write a Linux block device driver for Linux?

Question

I would like to write a Linux block device driver. The driver will not need to access the equipment so that it can be in user space.

To get started, I tried to build an example block device driver with this Makefile:

obj-m = sbd.o
KVERSION = $(shell pwd)
PWD = $(shell pwd)

all:
    make -C /lib/modules/$(KVERSION)/build M=$(PWD) modules

I am still getting these errors, which I don’t know how to fix. Here is stdout and stderr:

make -C /lib/modules/2.6.31-19-generic/build M=/home/andreas/sp/nivoa/src/driver/sbd modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.31-19-generic'
  CC [M]  /home/andreas/sp/nivoa/src/driver/sbd/sbd.o
/home/andreas/sp/nivoa/src/driver/sbd/sbd.c:72: error: expected ‘)’ before ‘*’ token
/home/andreas/sp/nivoa/src/driver/sbd/sbd.c:128: warning: initialization from incompatible pointer type
/home/andreas/sp/nivoa/src/driver/sbd/sbd.c: In function ‘sbd_init’:
/home/andreas/sp/nivoa/src/driver/sbd/sbd.c:143: error: ‘sbd_request’ undeclared (first use in this function)
/home/andreas/sp/nivoa/src/driver/sbd/sbd.c:143: error: (Each undeclared identifier is reported only once
/home/andreas/sp/nivoa/src/driver/sbd/sbd.c:143: error: for each function it appears in.)
/home/andreas/sp/nivoa/src/driver/sbd/sbd.c:146: error: implicit declaration of function ‘blk_queue_hardsect_size’
make[2]: *** [/home/andreas/sp/nivoa/src/driver/sbd/sbd.o] Error 1
make[1]: *** [_module_/home/andreas/sp/nivoa/src/driver/sbd] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.31-19-generic'
make: *** [all] Error 2

Any help on this would be greatly appreciated.

Thanks Andreas

Answer 1

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Answer 2

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Answer 3

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Answer 4

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Answer 5

NBD. nbdkit, ( C, ). FOSDEM 2019, Linux .