343 lines
8.7 KiB
C
343 lines
8.7 KiB
C
/* BSD Kernel Data Access Library (libkvm) interface.
|
||
|
||
Copyright 2004, 2005 Free Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 2 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program; if not, write to the Free Software
|
||
Foundation, Inc., 59 Temple Place - Suite 330,
|
||
Boston, MA 02111-1307, USA. */
|
||
|
||
#include "defs.h"
|
||
#include "cli/cli-cmds.h"
|
||
#include "command.h"
|
||
#include "frame.h"
|
||
#include "regcache.h"
|
||
#include "target.h"
|
||
#include "value.h"
|
||
#include "gdbcore.h" /* for get_exec_file */
|
||
|
||
#include "gdb_assert.h"
|
||
#include <fcntl.h>
|
||
#include <kvm.h>
|
||
#ifdef HAVE_NLIST_H
|
||
#include <nlist.h>
|
||
#endif
|
||
#include <paths.h>
|
||
#include "readline/readline.h"
|
||
#include <sys/param.h>
|
||
#include <sys/proc.h>
|
||
#include <sys/user.h>
|
||
|
||
#include "bsd-kvm.h"
|
||
|
||
/* Kernel memory device file. */
|
||
static const char *bsd_kvm_corefile;
|
||
|
||
/* Kernel memory interface descriptor. */
|
||
static kvm_t *core_kd;
|
||
|
||
/* Address of process control block. */
|
||
static struct pcb *bsd_kvm_paddr;
|
||
|
||
/* Pointer to architecture-specific function that reconstructs the
|
||
register state from PCB and supplies it to REGCACHE. */
|
||
static int (*bsd_kvm_supply_pcb)(struct regcache *regcache, struct pcb *pcb);
|
||
|
||
/* Target ops for libkvm interface. */
|
||
static struct target_ops bsd_kvm_ops;
|
||
|
||
static void
|
||
bsd_kvm_open (char *filename, int from_tty)
|
||
{
|
||
char errbuf[_POSIX2_LINE_MAX];
|
||
char *execfile = NULL;
|
||
kvm_t *temp_kd;
|
||
|
||
target_preopen (from_tty);
|
||
|
||
if (filename)
|
||
{
|
||
char *temp;
|
||
|
||
filename = tilde_expand (filename);
|
||
if (filename[0] != '/')
|
||
{
|
||
temp = concat (current_directory, "/", filename, (char *)NULL);
|
||
xfree (filename);
|
||
filename = temp;
|
||
}
|
||
}
|
||
|
||
execfile = get_exec_file (0);
|
||
temp_kd = kvm_openfiles (execfile, filename, NULL, O_RDONLY, errbuf);
|
||
if (temp_kd == NULL)
|
||
error (("%s"), errbuf);
|
||
|
||
bsd_kvm_corefile = filename;
|
||
unpush_target (&bsd_kvm_ops);
|
||
core_kd = temp_kd;
|
||
push_target (&bsd_kvm_ops);
|
||
|
||
target_fetch_registers (-1);
|
||
|
||
flush_cached_frames ();
|
||
select_frame (get_current_frame ());
|
||
print_stack_frame (get_selected_frame (NULL), -1, 1);
|
||
}
|
||
|
||
static void
|
||
bsd_kvm_close (int quitting)
|
||
{
|
||
if (core_kd)
|
||
{
|
||
if (kvm_close (core_kd) == -1)
|
||
warning (("%s"), kvm_geterr(core_kd));
|
||
core_kd = NULL;
|
||
}
|
||
}
|
||
|
||
static LONGEST
|
||
bsd_kvm_xfer_memory (CORE_ADDR addr, ULONGEST len,
|
||
gdb_byte *readbuf, const gdb_byte *writebuf)
|
||
{
|
||
ssize_t nbytes = len;
|
||
|
||
if (readbuf)
|
||
nbytes = kvm_read (core_kd, addr, readbuf, nbytes);
|
||
if (writebuf && nbytes > 0)
|
||
nbytes = kvm_write (core_kd, addr, writebuf, nbytes);
|
||
return nbytes;
|
||
}
|
||
|
||
static LONGEST
|
||
bsd_kvm_xfer_partial (struct target_ops *ops, enum target_object object,
|
||
const char *annex, gdb_byte *readbuf,
|
||
const gdb_byte *writebuf,
|
||
ULONGEST offset, LONGEST len)
|
||
{
|
||
switch (object)
|
||
{
|
||
case TARGET_OBJECT_MEMORY:
|
||
return bsd_kvm_xfer_memory (offset, len, readbuf, writebuf);
|
||
|
||
default:
|
||
return -1;
|
||
}
|
||
}
|
||
|
||
static void
|
||
bsd_kvm_files_info (struct target_ops *ops)
|
||
{
|
||
if (bsd_kvm_corefile && strcmp (bsd_kvm_corefile, _PATH_MEM) != 0)
|
||
printf_filtered (_("\tUsing the kernel crash dump %s.\n"),
|
||
bsd_kvm_corefile);
|
||
else
|
||
printf_filtered (_("\tUsing the currently running kernel.\n"));
|
||
}
|
||
|
||
/* Fetch process control block at address PADDR. */
|
||
|
||
static int
|
||
bsd_kvm_fetch_pcb (struct pcb *paddr)
|
||
{
|
||
struct pcb pcb;
|
||
|
||
if (kvm_read (core_kd, (unsigned long) paddr, &pcb, sizeof pcb) == -1)
|
||
error (("%s"), kvm_geterr (core_kd));
|
||
|
||
gdb_assert (bsd_kvm_supply_pcb);
|
||
return bsd_kvm_supply_pcb (current_regcache, &pcb);
|
||
}
|
||
|
||
static void
|
||
bsd_kvm_fetch_registers (int regnum)
|
||
{
|
||
struct nlist nl[2];
|
||
|
||
if (bsd_kvm_paddr)
|
||
{
|
||
bsd_kvm_fetch_pcb (bsd_kvm_paddr);
|
||
return;
|
||
}
|
||
|
||
/* On dumping core, BSD kernels store the faulting context (PCB)
|
||
in the variable "dumppcb". */
|
||
memset (nl, 0, sizeof nl);
|
||
nl[0].n_name = "_dumppcb";
|
||
|
||
if (kvm_nlist (core_kd, nl) == -1)
|
||
error (("%s"), kvm_geterr (core_kd));
|
||
|
||
if (nl[0].n_value != 0)
|
||
{
|
||
/* Found dumppcb. If it contains a valid context, return
|
||
immediately. */
|
||
if (bsd_kvm_fetch_pcb ((struct pcb *) nl[0].n_value))
|
||
return;
|
||
}
|
||
|
||
/* Traditional BSD kernels have a process proc0 that should always
|
||
be present. The address of proc0's PCB is stored in the variable
|
||
"proc0paddr". */
|
||
|
||
memset (nl, 0, sizeof nl);
|
||
nl[0].n_name = "_proc0paddr";
|
||
|
||
if (kvm_nlist (core_kd, nl) == -1)
|
||
error (("%s"), kvm_geterr (core_kd));
|
||
|
||
if (nl[0].n_value != 0)
|
||
{
|
||
struct pcb *paddr;
|
||
|
||
/* Found proc0paddr. */
|
||
if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1)
|
||
error (("%s"), kvm_geterr (core_kd));
|
||
|
||
bsd_kvm_fetch_pcb (paddr);
|
||
return;
|
||
}
|
||
|
||
#ifdef HAVE_STRUCT_THREAD_TD_PCB
|
||
/* In FreeBSD kernels for 5.0-RELEASE and later, the PCB no longer
|
||
lives in `struct proc' but in `struct thread'. The `struct
|
||
thread' for the initial thread for proc0 can be found in the
|
||
variable "thread0". */
|
||
|
||
memset (nl, 0, sizeof nl);
|
||
nl[0].n_name = "_thread0";
|
||
|
||
if (kvm_nlist (core_kd, nl) == -1)
|
||
error (("%s"), kvm_geterr (core_kd));
|
||
|
||
if (nl[0].n_value != 0)
|
||
{
|
||
struct pcb *paddr;
|
||
|
||
/* Found thread0. */
|
||
nl[0].n_value += offsetof (struct thread, td_pcb);
|
||
if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1)
|
||
error (("%s"), kvm_geterr (core_kd));
|
||
|
||
bsd_kvm_fetch_pcb (paddr);
|
||
return;
|
||
}
|
||
#endif
|
||
|
||
/* i18n: PCB == "Process Control Block" */
|
||
error (_("Cannot find a valid PCB"));
|
||
}
|
||
|
||
|
||
/* Kernel memory interface commands. */
|
||
struct cmd_list_element *bsd_kvm_cmdlist;
|
||
|
||
static void
|
||
bsd_kvm_cmd (char *arg, int fromtty)
|
||
{
|
||
/* ??? Should this become an alias for "target kvm"? */
|
||
}
|
||
|
||
#ifndef HAVE_STRUCT_THREAD_TD_PCB
|
||
|
||
static void
|
||
bsd_kvm_proc_cmd (char *arg, int fromtty)
|
||
{
|
||
CORE_ADDR addr;
|
||
|
||
if (arg == NULL)
|
||
error_no_arg (_("proc address"));
|
||
|
||
if (core_kd == NULL)
|
||
error (_("No kernel memory image."));
|
||
|
||
addr = parse_and_eval_address (arg);
|
||
#ifdef HAVE_STRUCT_LWP
|
||
addr += offsetof (struct lwp, l_addr);
|
||
#else
|
||
addr += offsetof (struct proc, p_addr);
|
||
#endif
|
||
|
||
if (kvm_read (core_kd, addr, &bsd_kvm_paddr, sizeof bsd_kvm_paddr) == -1)
|
||
error (("%s"), kvm_geterr (core_kd));
|
||
|
||
target_fetch_registers (-1);
|
||
|
||
flush_cached_frames ();
|
||
select_frame (get_current_frame ());
|
||
print_stack_frame (get_selected_frame (NULL), -1, 1);
|
||
}
|
||
|
||
#endif
|
||
|
||
static void
|
||
bsd_kvm_pcb_cmd (char *arg, int fromtty)
|
||
{
|
||
if (arg == NULL)
|
||
/* i18n: PCB == "Process Control Block" */
|
||
error_no_arg (_("pcb address"));
|
||
|
||
if (core_kd == NULL)
|
||
error (_("No kernel memory image."));
|
||
|
||
bsd_kvm_paddr = (struct pcb *)(u_long) parse_and_eval_address (arg);
|
||
|
||
target_fetch_registers (-1);
|
||
|
||
flush_cached_frames ();
|
||
select_frame (get_current_frame ());
|
||
print_stack_frame (get_selected_frame (NULL), -1, 1);
|
||
}
|
||
|
||
/* Add the libkvm interface to the list of all possible targets and
|
||
register CUPPLY_PCB as the architecture-specific process control
|
||
block interpreter. */
|
||
|
||
void
|
||
bsd_kvm_add_target (int (*supply_pcb)(struct regcache *, struct pcb *))
|
||
{
|
||
gdb_assert (bsd_kvm_supply_pcb == NULL);
|
||
bsd_kvm_supply_pcb = supply_pcb;
|
||
|
||
bsd_kvm_ops.to_shortname = "kvm";
|
||
bsd_kvm_ops.to_longname = _("Kernel memory interface");
|
||
bsd_kvm_ops.to_doc = _("Use a kernel virtual memory image as a target.\n\
|
||
Optionally specify the filename of a core dump.");
|
||
bsd_kvm_ops.to_open = bsd_kvm_open;
|
||
bsd_kvm_ops.to_close = bsd_kvm_close;
|
||
bsd_kvm_ops.to_fetch_registers = bsd_kvm_fetch_registers;
|
||
bsd_kvm_ops.to_xfer_partial = bsd_kvm_xfer_partial;
|
||
bsd_kvm_ops.to_files_info = bsd_kvm_files_info;
|
||
bsd_kvm_ops.to_stratum = process_stratum;
|
||
bsd_kvm_ops.to_has_memory = 1;
|
||
bsd_kvm_ops.to_has_stack = 1;
|
||
bsd_kvm_ops.to_has_registers = 1;
|
||
bsd_kvm_ops.to_magic = OPS_MAGIC;
|
||
|
||
add_target (&bsd_kvm_ops);
|
||
|
||
add_prefix_cmd ("kvm", class_obscure, bsd_kvm_cmd, _("\
|
||
Generic command for manipulating the kernel memory interface."),
|
||
&bsd_kvm_cmdlist, "kvm ", 0, &cmdlist);
|
||
|
||
#ifndef HAVE_STRUCT_THREAD_TD_PCB
|
||
add_cmd ("proc", class_obscure, bsd_kvm_proc_cmd,
|
||
_("Set current context from proc address"), &bsd_kvm_cmdlist);
|
||
#endif
|
||
add_cmd ("pcb", class_obscure, bsd_kvm_pcb_cmd,
|
||
/* i18n: PCB == "Process Control Block" */
|
||
_("Set current context from pcb address"), &bsd_kvm_cmdlist);
|
||
}
|