1 /* BSD Kernel Data Access Library (libkvm) interface.
3 Copyright 2004, 2005 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"
37 #include "readline/readline.h"
38 #include <sys/param.h>
44 /* Kernel memory interface descriptor. */
47 /* Address of process control block. */
48 struct pcb *bsd_kvm_paddr;
50 /* Pointer to architecture-specific function that reconstructs the
51 register state from PCB and supplies it to REGCACHE. */
52 int (*bsd_kvm_supply_pcb)(struct regcache *regcache, struct pcb *pcb);
54 /* Target ops for libkvm interface. */
55 struct target_ops bsd_kvm_ops;
58 bsd_kvm_open (char *filename, int from_tty)
60 char errbuf[_POSIX2_LINE_MAX];
61 char *execfile = NULL;
64 target_preopen (from_tty);
70 filename = tilde_expand (filename);
71 if (filename[0] != '/')
73 temp = concat (current_directory, "/", filename, NULL);
79 execfile = get_exec_file (0);
80 temp_kd = kvm_openfiles (execfile, filename, NULL, O_RDONLY, errbuf);
82 error (("%s"), errbuf);
84 unpush_target (&bsd_kvm_ops);
86 push_target (&bsd_kvm_ops);
88 target_fetch_registers (-1);
90 flush_cached_frames ();
91 select_frame (get_current_frame ());
92 print_stack_frame (get_selected_frame (NULL), -1, 1);
96 bsd_kvm_close (int quitting)
100 if (kvm_close (core_kd) == -1)
101 warning (("%s"), kvm_geterr(core_kd));
107 bsd_kvm_xfer_memory (CORE_ADDR addr, ULONGEST len,
108 gdb_byte *readbuf, const gdb_byte *writebuf)
110 ssize_t nbytes = len;
113 nbytes = kvm_read (core_kd, addr, readbuf, nbytes);
114 if (writebuf && nbytes > 0)
115 nbytes = kvm_write (core_kd, addr, writebuf, nbytes);
120 bsd_kvm_xfer_partial (struct target_ops *ops, enum target_object object,
121 const char *annex, gdb_byte *readbuf,
122 const gdb_byte *writebuf,
123 ULONGEST offset, LONGEST len)
127 case TARGET_OBJECT_MEMORY:
128 return bsd_kvm_xfer_memory (offset, len, readbuf, writebuf);
135 /* Fetch process control block at address PADDR. */
138 bsd_kvm_fetch_pcb (struct pcb *paddr)
142 if (kvm_read (core_kd, (unsigned long) paddr, &pcb, sizeof pcb) == -1)
143 error (("%s"), kvm_geterr (core_kd));
145 gdb_assert (bsd_kvm_supply_pcb);
146 return bsd_kvm_supply_pcb (current_regcache, &pcb);
150 bsd_kvm_fetch_registers (int regnum)
156 bsd_kvm_fetch_pcb (bsd_kvm_paddr);
160 /* On dumping core, BSD kernels store the faulting context (PCB)
161 in the variable "dumppcb". */
162 memset (nl, 0, sizeof nl);
163 nl[0].n_name = "_dumppcb";
165 if (kvm_nlist (core_kd, nl) == -1)
166 error (("%s"), kvm_geterr (core_kd));
168 if (nl[0].n_value != 0)
170 /* Found dumppcb. If it contains a valid context, return
172 if (bsd_kvm_fetch_pcb ((struct pcb *) nl[0].n_value))
176 /* Traditional BSD kernels have a process proc0 that should always
177 be present. The address of proc0's PCB is stored in the variable
180 memset (nl, 0, sizeof nl);
181 nl[0].n_name = "_proc0paddr";
183 if (kvm_nlist (core_kd, nl) == -1)
184 error (("%s"), kvm_geterr (core_kd));
186 if (nl[0].n_value != 0)
190 /* Found proc0paddr. */
191 if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1)
192 error (("%s"), kvm_geterr (core_kd));
194 bsd_kvm_fetch_pcb (paddr);
198 #ifdef HAVE_STRUCT_THREAD_TD_PCB
199 /* In FreeBSD kernels for 5.0-RELEASE and later, the PCB no longer
200 lives in `struct proc' but in `struct thread'. The `struct
201 thread' for the initial thread for proc0 can be found in the
202 variable "thread0". */
204 memset (nl, 0, sizeof nl);
205 nl[0].n_name = "_thread0";
207 if (kvm_nlist (core_kd, nl) == -1)
208 error (("%s"), kvm_geterr (core_kd));
210 if (nl[0].n_value != 0)
215 nl[0].n_value += offsetof (struct thread, td_pcb);
216 if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1)
217 error (("%s"), kvm_geterr (core_kd));
219 bsd_kvm_fetch_pcb (paddr);
224 /* i18n: PCB == "Process Control Block" */
225 error (_("Cannot find a valid PCB"));
229 /* Kernel memory interface commands. */
230 struct cmd_list_element *bsd_kvm_cmdlist;
233 bsd_kvm_cmd (char *arg, int fromtty)
235 /* ??? Should this become an alias for "target kvm"? */
238 #ifndef HAVE_STRUCT_THREAD_TD_PCB
241 bsd_kvm_proc_cmd (char *arg, int fromtty)
246 error_no_arg (_("proc address"));
249 error (_("No kernel memory image."));
251 addr = parse_and_eval_address (arg);
252 #ifdef HAVE_STRUCT_LWP
253 addr += offsetof (struct lwp, l_addr);
255 addr += offsetof (struct proc, p_addr);
258 if (kvm_read (core_kd, addr, &bsd_kvm_paddr, sizeof bsd_kvm_paddr) == -1)
259 error (("%s"), kvm_geterr (core_kd));
261 target_fetch_registers (-1);
263 flush_cached_frames ();
264 select_frame (get_current_frame ());
265 print_stack_frame (get_selected_frame (NULL), -1, 1);
271 bsd_kvm_pcb_cmd (char *arg, int fromtty)
274 /* i18n: PCB == "Process Control Block" */
275 error_no_arg (_("pcb address"));
278 error (_("No kernel memory image."));
280 bsd_kvm_paddr = (struct pcb *)(u_long) parse_and_eval_address (arg);
282 target_fetch_registers (-1);
284 flush_cached_frames ();
285 select_frame (get_current_frame ());
286 print_stack_frame (get_selected_frame (NULL), -1, 1);
289 /* Add the libkvm interface to the list of all possible targets and
290 register CUPPLY_PCB as the architecture-specific process control
291 block interpreter. */
294 bsd_kvm_add_target (int (*supply_pcb)(struct regcache *, struct pcb *))
296 gdb_assert (bsd_kvm_supply_pcb == NULL);
297 bsd_kvm_supply_pcb = supply_pcb;
299 bsd_kvm_ops.to_shortname = "kvm";
300 bsd_kvm_ops.to_longname = _("Kernel memory interface");
301 bsd_kvm_ops.to_doc = _("Use a kernel virtual memory image as a target.\n\
302 Optionally specify the filename of a core dump.");
303 bsd_kvm_ops.to_open = bsd_kvm_open;
304 bsd_kvm_ops.to_close = bsd_kvm_close;
305 bsd_kvm_ops.to_fetch_registers = bsd_kvm_fetch_registers;
306 bsd_kvm_ops.to_xfer_partial = bsd_kvm_xfer_partial;
307 bsd_kvm_ops.to_stratum = process_stratum;
308 bsd_kvm_ops.to_has_memory = 1;
309 bsd_kvm_ops.to_has_stack = 1;
310 bsd_kvm_ops.to_has_registers = 1;
311 bsd_kvm_ops.to_magic = OPS_MAGIC;
313 add_target (&bsd_kvm_ops);
315 add_prefix_cmd ("kvm", class_obscure, bsd_kvm_cmd, _("\
316 Generic command for manipulating the kernel memory interface."),
317 &bsd_kvm_cmdlist, "kvm ", 0, &cmdlist);
319 #ifndef HAVE_STRUCT_THREAD_TD_PCB
320 add_cmd ("proc", class_obscure, bsd_kvm_proc_cmd,
321 _("Set current context from proc address"), &bsd_kvm_cmdlist);
323 add_cmd ("pcb", class_obscure, bsd_kvm_pcb_cmd,
324 /* i18n: PCB == "Process Control Block" */
325 _("Set current context from pcb address"), &bsd_kvm_cmdlist);