FreeBSD Device Drivers

A (Somewhat) Simple Example

Now that you’re familiar with the CAM subsystem, let’s work through some code. After that, I’ll detail the different CAM-related functions.

Example 14-1 is a SIM for a pseudo-HBA (taken from the mfi(4) code base).

Note

Take a quick look at this code and try to discern some of its structure. If you don’t understand all of it, don’t worry; an explanation follows.

Example 14-1. mfi_cam.c

#include <sys/param.h> #include <sys/module.h> #include <sys/kernel.h> #include <sys/systm.h> #include <sys/selinfo.h> #include <sys/bus.h> #include <sys/conf.h> #include <sys/bio.h> #include <sys/malloc.h> #include <sys/uio.h> #include <cam/cam.h> #include <cam/cam_ccb.h> #include <cam/cam_debug.h> #include <cam/cam_sim.h> #include <cam/cam_xpt_sim.h> ...