1 /* BSD Kernel Data Access Library (libkvm) interface.
3 Copyright 2004 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 #include "cli/cli-cmds.h"
29 #include "gdbcore.h" /* for get_exec_file */
31 #include "gdb_assert.h"
35 #include "readline/readline.h"
36 #include <sys/param.h>
42 /* Kernel memory interface descriptor. */
45 /* Address of process control block. */
46 struct pcb *bsd_kvm_paddr;
48 /* Pointer to architecture-specific function that reconstructs the
49 register state from PCB and supplies it to REGCACHE. */
50 int (*bsd_kvm_supply_pcb)(struct regcache *regcache, struct pcb *pcb);
52 /* Target ops for libkvm interface. */
53 struct target_ops bsd_kvm_ops;
56 bsd_kvm_open (char *filename, int from_tty)
58 char errbuf[_POSIX2_LINE_MAX];
59 char *execfile = NULL;
62 target_preopen (from_tty);
68 filename = tilde_expand (filename);
69 if (filename[0] != '/')
71 temp = concat (current_directory, "/", filename, NULL);
77 execfile = get_exec_file (0);
78 temp_kd = kvm_openfiles (execfile, filename, NULL, O_RDONLY, errbuf);
82 unpush_target (&bsd_kvm_ops);
84 push_target (&bsd_kvm_ops);
86 target_fetch_registers (-1);
88 flush_cached_frames ();
89 select_frame (get_current_frame ());
90 print_stack_frame (get_selected_frame (), -1, 1);
94 bsd_kvm_close (int quitting)
98 if (kvm_close (core_kd) == -1)
99 warning ("%s", kvm_geterr(core_kd));
105 bsd_kvm_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len,
106 int write, struct mem_attrib *attrib,
107 struct target_ops *ops)
110 return kvm_write (core_kd, memaddr, myaddr, len);
112 return kvm_read (core_kd, memaddr, myaddr, len);
117 /* Fetch process control block at address PADDR. */
120 bsd_kvm_fetch_pcb (struct pcb *paddr)
124 if (kvm_read (core_kd, (unsigned long) paddr, &pcb, sizeof pcb) == -1)
125 error ("%s", kvm_geterr (core_kd));
127 gdb_assert (bsd_kvm_supply_pcb);
128 return bsd_kvm_supply_pcb (current_regcache, &pcb);
132 bsd_kvm_fetch_registers (int regnum)
138 bsd_kvm_fetch_pcb (bsd_kvm_paddr);
142 /* On dumping core, BSD kernels store the faulting context (PCB)
143 in the variable "dumppcb". */
144 memset (nl, 0, sizeof nl);
145 nl[0].n_name = "_dumppcb";
147 if (kvm_nlist (core_kd, nl) == -1)
148 error ("%s", kvm_geterr (core_kd));
150 if (nl[0].n_value != 0)
152 /* Found dumppcb. If it contains a valid context, return
154 if (bsd_kvm_fetch_pcb ((struct pcb *) nl[0].n_value))
158 /* Traditional BSD kernels have a process proc0 that should always
159 be present. The address of proc0's PCB is stored in the variable
162 memset (nl, 0, sizeof nl);
163 nl[0].n_name = "_proc0paddr";
165 if (kvm_nlist (core_kd, nl) == -1)
166 error ("%s", kvm_geterr (core_kd));
168 if (nl[0].n_value != 0)
172 /* Found proc0paddr. */
173 if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1)
174 error ("%s", kvm_geterr (core_kd));
176 bsd_kvm_fetch_pcb (paddr);
180 #ifdef HAVE_STRUCT_THREAD_TD_PCB
181 /* In FreeBSD kernels for 5.0-RELEASE and later, the PCB no longer
182 lives in `struct proc' but in `struct thread'. The `struct
183 thread' for the initial thread for proc0 can be found in the
184 variable "thread0". */
186 memset (nl, 0, sizeof nl);
187 nl[0].n_name = "_thread0";
189 if (kvm_nlist (core_kd, nl) == -1)
190 error ("%s", kvm_geterr (core_kd));
192 if (nl[0].n_value != 0)
197 nl[0].n_value += offsetof (struct thread, td_pcb);
198 if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1)
199 error ("%s", kvm_geterr (core_kd));
201 bsd_kvm_fetch_pcb (paddr);
206 error ("Cannot find a valid PCB");
210 /* Kernel memory interface commands. */
211 struct cmd_list_element *bsd_kvm_cmdlist;
214 bsd_kvm_cmd (char *arg, int fromtty)
216 /* ??? Should this become an alias for "target kvm"? */
219 #ifndef HAVE_STRUCT_THREAD_TD_PCB
222 bsd_kvm_proc_cmd (char *arg, int fromtty)
227 error_no_arg ("proc address");
230 error ("No kernel memory image.");
232 addr = parse_and_eval_address (arg);
233 addr += offsetof (struct proc, p_addr);
235 if (kvm_read (core_kd, addr, &bsd_kvm_paddr, sizeof bsd_kvm_paddr) == -1)
236 error ("%s", kvm_geterr (core_kd));
238 target_fetch_registers (-1);
240 flush_cached_frames ();
241 select_frame (get_current_frame ());
242 print_stack_frame (get_selected_frame (), -1, 1);
248 bsd_kvm_pcb_cmd (char *arg, int fromtty)
251 error_no_arg ("pcb address");
254 error ("No kernel memory image.");
256 bsd_kvm_paddr = (struct pcb *) parse_and_eval_address (arg);
258 target_fetch_registers (-1);
260 flush_cached_frames ();
261 select_frame (get_current_frame ());
262 print_stack_frame (get_selected_frame (), -1, 1);
265 /* Add the libkvm interface to the list of all possible targets and
266 register CUPPLY_PCB as the architecture-specific process control
267 block interpreter. */
270 bsd_kvm_add_target (int (*supply_pcb)(struct regcache *, struct pcb *))
272 gdb_assert (bsd_kvm_supply_pcb == NULL);
273 bsd_kvm_supply_pcb = supply_pcb;
275 bsd_kvm_ops.to_shortname = "kvm";
276 bsd_kvm_ops.to_longname = "Kernel memory interface";
277 bsd_kvm_ops.to_doc = "Use a kernel virtual memory image as a target.\n\
278 Optionally specify the filename of a core dump.";
279 bsd_kvm_ops.to_open = bsd_kvm_open;
280 bsd_kvm_ops.to_close = bsd_kvm_close;
281 bsd_kvm_ops.to_fetch_registers = bsd_kvm_fetch_registers;
282 bsd_kvm_ops.to_xfer_memory = bsd_kvm_xfer_memory;
283 bsd_kvm_ops.to_stratum = process_stratum;
284 bsd_kvm_ops.to_has_memory = 1;
285 bsd_kvm_ops.to_has_stack = 1;
286 bsd_kvm_ops.to_has_registers = 1;
287 bsd_kvm_ops.to_magic = OPS_MAGIC;
289 add_target (&bsd_kvm_ops);
291 add_prefix_cmd ("kvm", class_obscure, bsd_kvm_cmd, "\
292 Generic command for manipulating the kernel memory interface.",
293 &bsd_kvm_cmdlist, "kvm ", 0, &cmdlist);
295 #ifndef HAVE_STRUCT_THREAD_TD_PCB
296 add_cmd ("proc", class_obscure, bsd_kvm_proc_cmd,
297 "Set current context from proc address", &bsd_kvm_cmdlist);
299 add_cmd ("pcb", class_obscure, bsd_kvm_pcb_cmd,
300 "Set current context from pcb address", &bsd_kvm_cmdlist);