IPKDB(9) BSD Kernel Developer's Manual IPKDB(9)NAME
ipkdb — machine-dependent interface to ipkdb
SYNOPSIS
#include <ipkdb/ipkdb.h>
void
ipkdb_init(void);
void
ipkdb_connect(int when);
int
ipkdbcmds(void);
void
ipkdbinit(void);
void
ipkdb_trap(void);
int
ipkdb_poll(void);
int
ipkdbif_init(struct ipkdb_if *kip);
int
ipkdbfbyte(u_char *c);
int
ipkdbsbyte(u_char *c, int i);
DESCRIPTION
The machine-dependent code must support this interface for operation with
ipkdb(4).
During system bootstrap, machine-dependent code must invoke ipkdb_init().
If the kernel is booted with RB_KDB set in boothowto (see boothowto(9)),
ipkdb(4) is enabled by invoking ipkdb_connect(), setting the when argu‐
ment to 0.
ipkdbcmds() is invoked by machine-dependent code when the trap mechanism
determines that the debugger should be entered, i.e., on a single step or
breakpoint interrupt from kernel code. The trapping mechanism should
already have stored the registers into the global area ipkdbregs. The
layout of this area must be the same as that expected by gdb(1). Valid
return values are:
IPKDB_CMD_RUN user wants to continue
IPKDB_CMD_STEP user wants to do single stepping
IPKDB_CMD_EXIT user has detached from debugging
FUNCTIONS
The machine-dependent code must provide the following functions for the
machine-independent code.
ipkdbinit() This routine gets called when the debugger should be
entered for the first time.
ipkdb_trap() This routine is part of the trap handler. Whenever
a trap happens (e.g., when hitting a breakpoint dur‐
ing debugging), ipkdb_trap() decides if the Debugger
needs to be called. If there are other ways to
decide that, it's not necessary to provide an
ipkdb_trap() implementation.
ipkdb_poll() This routine gets called after a panic to check for
a key press by the user. If implemented it allows
the user to press any key on the console to do the
automatic reboot after a panic. Otherwise the
debugging interface will wait forever for some
remote debugger to attach in case of a panic.
ipkdbif_init(kip) In order to be able to find the debugging interface,
the network driver must invoke ipkdbif_init() with
kip specifying a struct ipkdb_if plus some addi‐
tional parameters that allow it to access the
devices registers, hopefully using bus_space(9)
methods. In the ipkdb_if structure, the attach rou‐
tine must initialize the following fields:
myenetaddr fill this with the own ethernet
address of the device/machine
flags mark at least IPKDB_MYHW here
name name of the device, only used for
a message
start routine called every time ipkdb is
entered
leave routine called every time ipkdb is
left
receive routine called to receive a packet
send routine called to send a packet
Additional fields that may be set are:
myinetaddr fill this with the own internet
address, and mark IPKDB_MYIP in
flags
port may be used as a pointer to some
device
ipkdbfbyte(c) This routine should fetch a byte from address c. It
must not enter any trap handling code, but instead
return -1 on inability to access the data.
ipkdbsbyte(c, i) This routine should set the byte pointed to by c to
the value given as i. The routine must not enter
any trap handling code. Furthermore it should reset
the modification bit in the relevant page table
entry to the value before the store.
SEE ALSOipkdb(4), boothowto(9)BSD September 4, 2009 BSD