Commit | Line | Data |
---|---|---|
2e0c3539 MK |
1 | /* BSD Kernel Data Access Library (libkvm) interface. |
2 | ||
3 | Copyright 2004 Free Software Foundation, Inc. | |
4 | ||
5 | This file is part of GDB. | |
6 | ||
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. | |
11 | ||
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. | |
16 | ||
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. */ | |
21 | ||
22 | #include "defs.h" | |
963c4174 MK |
23 | #include "cli/cli-cmds.h" |
24 | #include "command.h" | |
2e0c3539 MK |
25 | #include "frame.h" |
26 | #include "regcache.h" | |
27 | #include "target.h" | |
963c4174 | 28 | #include "value.h" |
2e0c3539 MK |
29 | |
30 | #include "gdb_assert.h" | |
31 | #include <fcntl.h> | |
32 | #include <kvm.h> | |
33 | #include <nlist.h> | |
34 | #include "readline/readline.h" | |
35 | #include <sys/param.h> | |
963c4174 | 36 | #include <sys/proc.h> |
2e0c3539 MK |
37 | #include <sys/user.h> |
38 | ||
39 | #include "bsd-kvm.h" | |
40 | ||
41 | /* Kernel memory interface descriptor. */ | |
42 | kvm_t *core_kd; | |
43 | ||
44 | /* Address of process control block. */ | |
45 | struct pcb *bsd_kvm_paddr; | |
46 | ||
47 | /* Pointer to architecture-specific function that reconstructs the | |
48 | register state from PCB and supplies it to REGCACHE. */ | |
49 | int (*bsd_kvm_supply_pcb)(struct regcache *regcache, struct pcb *pcb); | |
50 | ||
51 | /* Target ops for libkvm interface. */ | |
52 | struct target_ops bsd_kvm_ops; | |
53 | ||
54 | static void | |
55 | bsd_kvm_open (char *filename, int from_tty) | |
56 | { | |
57 | char errbuf[_POSIX2_LINE_MAX]; | |
58 | char *execfile = NULL; | |
59 | kvm_t *temp_kd; | |
60 | ||
61 | target_preopen (from_tty); | |
62 | ||
63 | if (filename) | |
64 | { | |
65 | char *temp; | |
66 | ||
67 | filename = tilde_expand (filename); | |
68 | if (filename[0] != '/') | |
69 | { | |
70 | temp = concat (current_directory, "/", filename, NULL); | |
71 | xfree (filename); | |
72 | filename = temp; | |
73 | } | |
74 | } | |
75 | ||
76 | temp_kd = kvm_openfiles (execfile, filename, NULL, O_RDONLY, errbuf); | |
77 | if (temp_kd == NULL) | |
78 | error ("%s", errbuf); | |
79 | ||
80 | unpush_target (&bsd_kvm_ops); | |
81 | core_kd = temp_kd; | |
82 | push_target (&bsd_kvm_ops); | |
83 | ||
84 | target_fetch_registers (-1); | |
85 | ||
86 | flush_cached_frames (); | |
87 | select_frame (get_current_frame ()); | |
88 | print_stack_frame (get_selected_frame (), -1, 1); | |
89 | } | |
90 | ||
91 | static void | |
92 | bsd_kvm_close (int quitting) | |
93 | { | |
94 | if (core_kd) | |
95 | { | |
96 | if (kvm_close (core_kd) == -1) | |
97 | warning ("%s", kvm_geterr(core_kd)); | |
98 | core_kd = NULL; | |
99 | } | |
100 | } | |
101 | ||
102 | static int | |
103 | bsd_kvm_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, | |
104 | int write, struct mem_attrib *attrib, | |
105 | struct target_ops *ops) | |
106 | { | |
107 | if (write) | |
108 | return kvm_write (core_kd, memaddr, myaddr, len); | |
109 | else | |
110 | return kvm_read (core_kd, memaddr, myaddr, len); | |
111 | ||
112 | return -1; | |
113 | } | |
114 | ||
115 | /* Fetch process control block at address PADDR. */ | |
116 | ||
117 | static int | |
118 | bsd_kvm_fetch_pcb (struct pcb *paddr) | |
119 | { | |
120 | struct pcb pcb; | |
121 | ||
122 | if (kvm_read (core_kd, (unsigned long) paddr, &pcb, sizeof pcb) == -1) | |
123 | error ("%s", kvm_geterr (core_kd)); | |
124 | ||
125 | gdb_assert (bsd_kvm_supply_pcb); | |
126 | return bsd_kvm_supply_pcb (current_regcache, &pcb); | |
127 | } | |
128 | ||
129 | static void | |
130 | bsd_kvm_fetch_registers (int regnum) | |
131 | { | |
132 | struct nlist nl[2]; | |
133 | ||
134 | if (bsd_kvm_paddr) | |
efe1d7b9 MK |
135 | { |
136 | bsd_kvm_fetch_pcb (bsd_kvm_paddr); | |
137 | return; | |
138 | } | |
2e0c3539 MK |
139 | |
140 | /* On dumping core, BSD kernels store the faulting context (PCB) | |
141 | in the variable "dumppcb". */ | |
142 | memset (nl, 0, sizeof nl); | |
143 | nl[0].n_name = "_dumppcb"; | |
144 | ||
145 | if (kvm_nlist (core_kd, nl) == -1) | |
146 | error ("%s", kvm_geterr (core_kd)); | |
147 | ||
148 | if (nl[0].n_value != 0) | |
149 | { | |
150 | /* Found dumppcb. If it contains a valid context, return | |
151 | immediately. */ | |
152 | if (bsd_kvm_fetch_pcb ((struct pcb *) nl[0].n_value)) | |
153 | return; | |
154 | } | |
155 | ||
156 | /* Traditional BSD kernels have a process proc0 that should always | |
157 | be present. The address of proc0's PCB is stored in the variable | |
158 | "proc0paddr". */ | |
159 | ||
160 | memset (nl, 0, sizeof nl); | |
161 | nl[0].n_name = "_proc0paddr"; | |
162 | ||
163 | if (kvm_nlist (core_kd, nl) == -1) | |
164 | error ("%s", kvm_geterr (core_kd)); | |
165 | ||
166 | if (nl[0].n_value != 0) | |
167 | { | |
168 | struct pcb *paddr; | |
169 | ||
170 | /* Found proc0paddr. */ | |
171 | if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1) | |
172 | error ("%s", kvm_geterr (core_kd)); | |
173 | ||
174 | bsd_kvm_fetch_pcb (paddr); | |
175 | return; | |
176 | } | |
177 | ||
178 | #ifdef HAVE_STRUCT_THREAD_TD_PCB | |
179 | /* In FreeBSD kernels for 5.0-RELEASE and later, the PCB no longer | |
180 | lives in `struct proc' but in `struct thread'. The `struct | |
181 | thread' for the initial thread for proc0 can be found in the | |
182 | variable "thread0". */ | |
183 | ||
184 | memset (nl, 0, sizeof nl); | |
185 | nl[0].n_name = "_thread0"; | |
186 | ||
187 | if (kvm_nlist (core_kd, nl) == -1) | |
188 | error ("%s", kvm_geterr (core_kd)); | |
189 | ||
190 | if (nl[0].n_value != 0) | |
191 | { | |
192 | struct pcb *paddr; | |
193 | ||
194 | /* Found thread0. */ | |
efe1d7b9 MK |
195 | nl[0].n_value += offsetof (struct thread, td_pcb); |
196 | if (kvm_read (core_kd, nl[0].n_value, &paddr, sizeof paddr) == -1) | |
2e0c3539 MK |
197 | error ("%s", kvm_geterr (core_kd)); |
198 | ||
199 | bsd_kvm_fetch_pcb (paddr); | |
200 | return; | |
201 | } | |
202 | #endif | |
203 | ||
204 | error ("Cannot find a valid PCB"); | |
205 | } | |
206 | \f | |
207 | ||
963c4174 | 208 | /* Kernel memory interface commands. */ |
fdb1bf9d | 209 | struct cmd_list_element *bsd_kvm_cmdlist; |
963c4174 MK |
210 | |
211 | static void | |
212 | bsd_kvm_cmd (char *arg, int fromtty) | |
213 | { | |
214 | /* ??? Should this become an alias for "target kvm"? */ | |
215 | } | |
216 | ||
217 | #ifndef HAVE_STRUCT_THREAD_TD_PCB | |
218 | ||
219 | static void | |
220 | bsd_kvm_proc_cmd (char *arg, int fromtty) | |
221 | { | |
222 | CORE_ADDR addr; | |
223 | ||
224 | if (arg == NULL) | |
225 | error_no_arg ("proc address"); | |
226 | ||
227 | if (core_kd == NULL) | |
228 | error ("No kernel memory image."); | |
229 | ||
230 | addr = parse_and_eval_address (arg); | |
231 | addr += offsetof (struct proc, p_addr); | |
232 | ||
233 | if (kvm_read (core_kd, addr, &bsd_kvm_paddr, sizeof bsd_kvm_paddr) == -1) | |
234 | error ("%s", kvm_geterr (core_kd)); | |
235 | ||
236 | target_fetch_registers (-1); | |
237 | ||
238 | flush_cached_frames (); | |
239 | select_frame (get_current_frame ()); | |
240 | print_stack_frame (get_selected_frame (), -1, 1); | |
241 | } | |
242 | ||
243 | #endif | |
244 | ||
245 | static void | |
246 | bsd_kvm_pcb_cmd (char *arg, int fromtty) | |
247 | { | |
248 | if (arg == NULL) | |
249 | error_no_arg ("pcb address"); | |
250 | ||
251 | if (core_kd == NULL) | |
252 | error ("No kernel memory image."); | |
253 | ||
254 | bsd_kvm_paddr = (struct pcb *) parse_and_eval_address (arg); | |
255 | ||
256 | target_fetch_registers (-1); | |
257 | ||
258 | flush_cached_frames (); | |
259 | select_frame (get_current_frame ()); | |
260 | print_stack_frame (get_selected_frame (), -1, 1); | |
261 | } | |
262 | ||
2e0c3539 MK |
263 | /* Add the libkvm interface to the list of all possible targets and |
264 | register CUPPLY_PCB as the architecture-specific process control | |
265 | block interpreter. */ | |
266 | ||
267 | void | |
268 | bsd_kvm_add_target (int (*supply_pcb)(struct regcache *, struct pcb *)) | |
269 | { | |
270 | gdb_assert (bsd_kvm_supply_pcb == NULL); | |
271 | bsd_kvm_supply_pcb = supply_pcb; | |
272 | ||
273 | bsd_kvm_ops.to_shortname = "kvm"; | |
274 | bsd_kvm_ops.to_longname = "Kernel memory interface"; | |
275 | bsd_kvm_ops.to_doc = "Use a kernel virtual memory image as a target.\n\ | |
276 | Optionally specify the filename of a core dump."; | |
277 | bsd_kvm_ops.to_open = bsd_kvm_open; | |
278 | bsd_kvm_ops.to_close = bsd_kvm_close; | |
279 | bsd_kvm_ops.to_fetch_registers = bsd_kvm_fetch_registers; | |
280 | bsd_kvm_ops.to_xfer_memory = bsd_kvm_xfer_memory; | |
281 | bsd_kvm_ops.to_stratum = process_stratum; | |
282 | bsd_kvm_ops.to_has_memory = 1; | |
283 | bsd_kvm_ops.to_has_stack = 1; | |
284 | bsd_kvm_ops.to_has_registers = 1; | |
285 | bsd_kvm_ops.to_magic = OPS_MAGIC; | |
286 | ||
287 | add_target (&bsd_kvm_ops); | |
963c4174 MK |
288 | |
289 | add_prefix_cmd ("kvm", class_obscure, bsd_kvm_cmd, "\ | |
290 | Generic command for manipulating the kernel memory interface.", | |
291 | &bsd_kvm_cmdlist, "kvm ", 0, &cmdlist); | |
292 | ||
293 | #ifndef HAVE_STRUCT_THREAD_TD_PCB | |
294 | add_cmd ("proc", class_obscure, bsd_kvm_proc_cmd, | |
295 | "Set current context from proc address", &bsd_kvm_cmdlist); | |
296 | #endif | |
297 | add_cmd ("pcb", class_obscure, bsd_kvm_pcb_cmd, | |
298 | "Set current context from pcb address", &bsd_kvm_cmdlist); | |
2e0c3539 | 299 | } |