xref: /netbsd-src/sys/miscfs/procfs/procfs_linux.c (revision aad9773e38ed2370a628a6416e098f9008fc10a7)
1 /*      $NetBSD: procfs_linux.c,v 1.70 2014/08/10 06:22:06 matt Exp $      */
2 
3 /*
4  * Copyright (c) 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Frank van der Linden for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: procfs_linux.c,v 1.70 2014/08/10 06:22:06 matt Exp $");
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/time.h>
44 #include <sys/cpu.h>
45 #include <sys/kernel.h>
46 #include <sys/proc.h>
47 #include <sys/vnode.h>
48 #include <sys/exec.h>
49 #include <sys/resource.h>
50 #include <sys/resourcevar.h>
51 #include <sys/signal.h>
52 #include <sys/signalvar.h>
53 #include <sys/tty.h>
54 #include <sys/malloc.h>
55 #include <sys/mount.h>
56 #include <sys/conf.h>
57 #include <sys/sysctl.h>
58 #include <sys/kauth.h>
59 #include <sys/filedesc.h>
60 
61 #include <miscfs/procfs/procfs.h>
62 
63 #include <compat/linux/common/linux_exec.h>
64 #include <compat/linux32/common/linux32_sysctl.h>
65 
66 #include <uvm/uvm_extern.h>
67 #include <uvm/uvm.h>
68 
69 extern struct devsw_conv *devsw_conv;
70 extern int max_devsw_convs;
71 
72 #define PGTOB(p)	((unsigned long)(p) << PAGE_SHIFT)
73 #define PGTOKB(p)	((unsigned long)(p) << (PAGE_SHIFT - 10))
74 
75 #define LBFSZ (8 * 1024)
76 
77 static void
78 get_proc_size_info(struct lwp *l, unsigned long *stext, unsigned long *etext, unsigned long *sstack)
79 {
80 	struct proc *p = l->l_proc;
81 	struct vmspace *vm;
82 	struct vm_map *map;
83 	struct vm_map_entry *entry;
84 
85 	*stext = 0;
86 	*etext = 0;
87 	*sstack = 0;
88 
89 	proc_vmspace_getref(p, &vm);
90 	map = &vm->vm_map;
91 	vm_map_lock_read(map);
92 
93 	for (entry = map->header.next; entry != &map->header;
94 	    entry = entry->next) {
95 		if (UVM_ET_ISSUBMAP(entry))
96 			continue;
97 		/* assume text is the first entry */
98 		if (*stext == *etext) {
99 			*stext = entry->start;
100 			*etext = entry->end;
101 			break;
102 		}
103 	}
104 #if defined(LINUX_USRSTACK32) && defined(USRSTACK32)
105 	if (strcmp(p->p_emul->e_name, "linux32") == 0 &&
106 	    LINUX_USRSTACK32 < USRSTACK32)
107 		*sstack = (unsigned long)LINUX_USRSTACK32;
108 	else
109 #endif
110 #ifdef LINUX_USRSTACK
111 	if (strcmp(p->p_emul->e_name, "linux") == 0 &&
112 	    LINUX_USRSTACK < USRSTACK)
113 		*sstack = (unsigned long)LINUX_USRSTACK;
114 	else
115 #endif
116 #ifdef	USRSTACK32
117 	if (strstr(p->p_emul->e_name, "32") != NULL)
118 		*sstack = (unsigned long)USRSTACK32;
119 	else
120 #endif
121 		*sstack = (unsigned long)USRSTACK;
122 
123 	/*
124 	 * jdk 1.6 compares low <= addr && addr < high
125 	 * if we put addr == high, then the test fails
126 	 * so eat one page.
127 	 */
128 	*sstack -= PAGE_SIZE;
129 
130 	vm_map_unlock_read(map);
131 	uvmspace_free(vm);
132 }
133 
134 /*
135  * Linux compatible /proc/meminfo. Only active when the -o linux
136  * mountflag is used.
137  */
138 int
139 procfs_domeminfo(struct lwp *curl, struct proc *p,
140     struct pfsnode *pfs, struct uio *uio)
141 {
142 	char *bf;
143 	int len;
144 	int error = 0;
145 
146 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
147 
148 	len = snprintf(bf, LBFSZ,
149 		"        total:    used:    free:  shared: buffers: cached:\n"
150 		"Mem:  %8lu %8lu %8lu %8lu %8lu %8lu\n"
151 		"Swap: %8lu %8lu %8lu\n"
152 		"MemTotal:  %8lu kB\n"
153 		"MemFree:   %8lu kB\n"
154 		"MemShared: %8lu kB\n"
155 		"Buffers:   %8lu kB\n"
156 		"Cached:    %8lu kB\n"
157 		"SwapTotal: %8lu kB\n"
158 		"SwapFree:  %8lu kB\n",
159 		PGTOB(uvmexp.npages),
160 		PGTOB(uvmexp.npages - uvmexp.free),
161 		PGTOB(uvmexp.free),
162 		0L,
163 		PGTOB(uvmexp.filepages),
164 		PGTOB(uvmexp.anonpages + uvmexp.filepages + uvmexp.execpages),
165 		PGTOB(uvmexp.swpages),
166 		PGTOB(uvmexp.swpginuse),
167 		PGTOB(uvmexp.swpages - uvmexp.swpginuse),
168 		PGTOKB(uvmexp.npages),
169 		PGTOKB(uvmexp.free),
170 		0L,
171 		PGTOKB(uvmexp.filepages),
172 		PGTOKB(uvmexp.anonpages + uvmexp.filepages + uvmexp.execpages),
173 		PGTOKB(uvmexp.swpages),
174 		PGTOKB(uvmexp.swpages - uvmexp.swpginuse));
175 
176 	if (len == 0)
177 		goto out;
178 
179 	error = uiomove_frombuf(bf, len, uio);
180 out:
181 	free(bf, M_TEMP);
182 	return error;
183 }
184 
185 /*
186  * Linux compatible /proc/devices. Only active when the -o linux
187  * mountflag is used.
188  */
189 int
190 procfs_dodevices(struct lwp *curl, struct proc *p,
191     struct pfsnode *pfs, struct uio *uio)
192 {
193 	char *bf;
194 	int offset = 0;
195 	int i, error = ENAMETOOLONG;
196 
197 	/* XXX elad - may need filtering. */
198 
199 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
200 
201 	offset += snprintf(&bf[offset], LBFSZ - offset, "Character devices:\n");
202 	if (offset >= LBFSZ)
203 		goto out;
204 
205 	mutex_enter(&device_lock);
206 	for (i = 0; i < max_devsw_convs; i++) {
207 		if ((devsw_conv[i].d_name == NULL) ||
208 		    (devsw_conv[i].d_cmajor == -1))
209 			continue;
210 
211 		offset += snprintf(&bf[offset], LBFSZ - offset,
212 		    "%3d %s\n", devsw_conv[i].d_cmajor, devsw_conv[i].d_name);
213 		if (offset >= LBFSZ) {
214 			mutex_exit(&device_lock);
215 			goto out;
216 		}
217 	}
218 
219 	offset += snprintf(&bf[offset], LBFSZ - offset, "\nBlock devices:\n");
220 	if (offset >= LBFSZ) {
221 		mutex_exit(&device_lock);
222 		goto out;
223 	}
224 
225 	for (i = 0; i < max_devsw_convs; i++) {
226 		if ((devsw_conv[i].d_name == NULL) ||
227 		    (devsw_conv[i].d_bmajor == -1))
228 			continue;
229 
230 		offset += snprintf(&bf[offset], LBFSZ - offset,
231 		    "%3d %s\n", devsw_conv[i].d_bmajor, devsw_conv[i].d_name);
232 		if (offset >= LBFSZ) {
233 			mutex_exit(&device_lock);
234 			goto out;
235 		}
236 	}
237 	mutex_exit(&device_lock);
238 
239 	error = uiomove_frombuf(bf, offset, uio);
240 out:
241 	free(bf, M_TEMP);
242 	return error;
243 }
244 
245 /*
246  * Linux compatible /proc/stat. Only active when the -o linux
247  * mountflag is used.
248  */
249 int
250 procfs_docpustat(struct lwp *curl, struct proc *p,
251     struct pfsnode *pfs, struct uio *uio)
252 {
253 	char		*bf;
254 	int	 	 error;
255 	int	 	 len;
256 #if defined(MULTIPROCESSOR)
257         struct cpu_info *ci;
258         CPU_INFO_ITERATOR cii;
259 #endif
260 	int	 	 i;
261 	uint64_t	nintr;
262 	uint64_t	nswtch;
263 
264 	error = ENAMETOOLONG;
265 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
266 
267 	len = snprintf(bf, LBFSZ,
268 		"cpu %" PRIu64 " %" PRIu64 " %" PRIu64 " %" PRIu64 "\n",
269 		curcpu()->ci_schedstate.spc_cp_time[CP_USER],
270 		curcpu()->ci_schedstate.spc_cp_time[CP_NICE],
271 		curcpu()->ci_schedstate.spc_cp_time[CP_SYS] /*+ [CP_INTR]*/,
272 		curcpu()->ci_schedstate.spc_cp_time[CP_IDLE]);
273 	if (len == 0)
274 		goto out;
275 
276 #if defined(MULTIPROCESSOR)
277 #define ALLCPUS	CPU_INFO_FOREACH(cii, ci)
278 #define CPUNAME	ci
279 #else
280 #define ALLCPUS	; i < 1 ;
281 #define CPUNAME	curcpu()
282 #endif
283 
284 	i = 0;
285 	nintr = 0;
286 	nswtch = 0;
287 	for (ALLCPUS) {
288 		len += snprintf(&bf[len], LBFSZ - len,
289 			"cpu%d %" PRIu64 " %" PRIu64 " %" PRIu64 " %" PRIu64
290 			"\n", i,
291 			CPUNAME->ci_schedstate.spc_cp_time[CP_USER],
292 			CPUNAME->ci_schedstate.spc_cp_time[CP_NICE],
293 			CPUNAME->ci_schedstate.spc_cp_time[CP_SYS],
294 			CPUNAME->ci_schedstate.spc_cp_time[CP_IDLE]);
295 		if (len >= LBFSZ)
296 			goto out;
297 		i += 1;
298 		nintr += CPUNAME->ci_data.cpu_nintr;
299 		nswtch += CPUNAME->ci_data.cpu_nswtch;
300 	}
301 
302 	len += snprintf(&bf[len], LBFSZ - len,
303 			"disk 0 0 0 0\n"
304 			"page %u %u\n"
305 			"swap %u %u\n"
306 			"intr %"PRIu64"\n"
307 			"ctxt %"PRIu64"\n"
308 			"btime %"PRId64"\n",
309 			uvmexp.pageins, uvmexp.pdpageouts,
310 			uvmexp.pgswapin, uvmexp.pgswapout,
311 			nintr,
312 			nswtch,
313 			boottime.tv_sec);
314 	if (len >= LBFSZ)
315 		goto out;
316 
317 	error = uiomove_frombuf(bf, len, uio);
318 out:
319 	free(bf, M_TEMP);
320 	return error;
321 }
322 
323 /*
324  * Linux compatible /proc/loadavg. Only active when the -o linux
325  * mountflag is used.
326  */
327 int
328 procfs_doloadavg(struct lwp *curl, struct proc *p,
329     struct pfsnode *pfs, struct uio *uio)
330 {
331 	char	*bf;
332 	int 	 error;
333 	int 	 len;
334 
335 	error = ENAMETOOLONG;
336 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
337 
338 	averunnable.fscale = FSCALE;
339 	len = snprintf(bf, LBFSZ,
340 	        "%d.%02d %d.%02d %d.%02d %d/%d %d\n",
341 		(int)(averunnable.ldavg[0] / averunnable.fscale),
342 		(int)(averunnable.ldavg[0] * 100 / averunnable.fscale % 100),
343 		(int)(averunnable.ldavg[1] / averunnable.fscale),
344 		(int)(averunnable.ldavg[1] * 100 / averunnable.fscale % 100),
345 		(int)(averunnable.ldavg[2] / averunnable.fscale),
346 		(int)(averunnable.ldavg[2] * 100 / averunnable.fscale % 100),
347 		1,		/* number of ONPROC processes */
348 		nprocs,
349 		30000);		/* last pid */
350 	if (len == 0)
351 		goto out;
352 
353 	error = uiomove_frombuf(bf, len, uio);
354 out:
355 	free(bf, M_TEMP);
356 	return error;
357 }
358 
359 /*
360  * Linux compatible /proc/<pid>/statm. Only active when the -o linux
361  * mountflag is used.
362  */
363 int
364 procfs_do_pid_statm(struct lwp *curl, struct lwp *l,
365     struct pfsnode *pfs, struct uio *uio)
366 {
367 	struct vmspace	*vm;
368 	struct proc	*p = l->l_proc;
369 	struct rusage	*ru = &p->p_stats->p_ru;
370 	char		*bf;
371 	int	 	 error;
372 	int	 	 len;
373 
374 	error = ENAMETOOLONG;
375 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
376 
377 	/* XXX - we use values from vmspace, since dsl says that ru figures
378 	   are always 0 except for zombies. See kvm_proc.c::kvm_getproc2() */
379 	if ((error = proc_vmspace_getref(p, &vm)) != 0) {
380 		goto out;
381 	}
382 
383 	len = snprintf(bf, LBFSZ,
384 	        "%lu %lu %lu %lu %lu %lu %lu\n",
385 		(unsigned long)(vm->vm_tsize + vm->vm_dsize + vm->vm_ssize), /* size */
386 		(unsigned long)(vm->vm_rssize),	/* resident */
387 		(unsigned long)(ru->ru_ixrss),	/* shared */
388 		(unsigned long)(vm->vm_tsize),	/* text size in pages */
389 		(unsigned long)(vm->vm_dsize),	/* data size in pages */
390 		(unsigned long)(vm->vm_ssize),	/* stack size in pages */
391 		(unsigned long) 0);
392 
393 	uvmspace_free(vm);
394 
395 	if (len == 0)
396 		goto out;
397 
398 	error = uiomove_frombuf(bf, len, uio);
399 out:
400 	free(bf, M_TEMP);
401 	return error;
402 }
403 
404 #define UTIME2TICKS(s,u)	(((uint64_t)(s) * 1000000 + (u)) / 10000)
405 
406 /*
407  * Linux compatible /proc/<pid>/stat. Only active when the -o linux
408  * mountflag is used.
409  */
410 int
411 procfs_do_pid_stat(struct lwp *curl, struct lwp *l,
412     struct pfsnode *pfs, struct uio *uio)
413 {
414 	char *bf;
415 	struct proc *p = l->l_proc;
416 	int len;
417 	struct rusage *cru = &p->p_stats->p_cru;
418 	unsigned long stext = 0, etext = 0, sstack = 0;
419 	struct timeval rt;
420 	struct vmspace	*vm;
421 	struct kinfo_proc2 ki;
422 	int error = 0;
423 
424 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
425 
426 	if ((error = proc_vmspace_getref(p, &vm)) != 0) {
427 		goto out;
428 	}
429 
430 	get_proc_size_info(l, &stext, &etext, &sstack);
431 
432 	mutex_enter(proc_lock);
433 	mutex_enter(p->p_lock);
434 
435 	fill_kproc2(p, &ki, false);
436 	calcru(p, NULL, NULL, NULL, &rt);
437 
438 	len = snprintf(bf, LBFSZ,
439 	    "%d (%s) %c %d %d %d %u %d "
440 	    "%u "
441 	    "%"PRIu64" %lu %"PRIu64" %lu %"PRIu64" %"PRIu64" %"PRIu64" %"PRIu64" "
442 	    "%d %d %"PRIu64" "
443 	    "%lld %"PRIu64" %"PRId64" %lu %"PRIu64" "
444 	    "%lu %lu %lu "
445 	    "%u %u "
446 	    "%u %u %u %u "
447 	    "%"PRIu64" %"PRIu64" %"PRIu64" %d %"PRIu64"\n",
448 
449 	    ki.p_pid,						/* 1 pid */
450 	    ki.p_comm,						/* 2 tcomm */
451 	    "0RRSTZXR8"[(ki.p_stat > 8) ? 0 : (int)ki.p_stat],	/* 3 state */
452 	    ki.p_ppid,						/* 4 ppid */
453 	    ki.p__pgid,						/* 5 pgrp */
454 	    ki.p_sid,						/* 6 sid */
455 	    (ki.p_tdev != (uint32_t)NODEV) ? ki.p_tdev : 0,	/* 7 tty_nr */
456 	    ki.p_tpgid,						/* 8 tty_pgrp */
457 
458 	    ki.p_flag,						/* 9 flags */
459 
460 	    ki.p_uru_minflt,					/* 10 min_flt */
461 	    cru->ru_minflt,
462 	    ki.p_uru_majflt,					/* 12 maj_flt */
463 	    cru->ru_majflt,
464 	    UTIME2TICKS(ki.p_uutime_sec, ki.p_uutime_usec),	/* 14 utime */
465 	    UTIME2TICKS(ki.p_ustime_sec, ki.p_ustime_usec),	/* 15 stime */
466 	    UTIME2TICKS(cru->ru_utime.tv_sec, cru->ru_utime.tv_usec), /* 16 cutime */
467 	    UTIME2TICKS(cru->ru_stime.tv_sec, cru->ru_stime.tv_usec), /* 17 cstime */
468 
469 	    ki.p_priority,				/* XXX: 18 priority */
470 	    ki.p_nice - NZERO,				/* 19 nice */
471 	    ki.p_nlwps,					/* 20 num_threads */
472 
473 	    (long long)rt.tv_sec,
474 	    UTIME2TICKS(ki.p_ustart_sec, ki.p_ustart_usec), /* 22 start_time */
475 	    ki.p_vm_msize,				/* 23 vsize */
476 	    PGTOKB(ki.p_vm_rssize),			/* 24 rss */
477 	    p->p_rlimit[RLIMIT_RSS].rlim_cur,		/* 25 rsslim */
478 
479 	    stext,					/* 26 start_code */
480 	    etext,					/* 27 end_code */
481 	    sstack,					/* 28 start_stack */
482 
483 	    0,						/* XXX: 29 esp */
484 	    0,						/* XXX: 30 eip */
485 
486 	    ki.p_siglist.__bits[0],			/* XXX: 31 pending */
487 	    0,						/* XXX: 32 blocked */
488 	    ki.p_sigignore.__bits[0],		/* 33 sigign */
489 	    ki.p_sigcatch.__bits[0],		/* 34 sigcatch */
490 
491 	    ki.p_wchan,					/* 35 wchan */
492 	    ki.p_uru_nvcsw,
493 	    ki.p_uru_nivcsw,
494 	    ki.p_exitsig,				/* 38 exit_signal */
495 	    ki.p_cpuid);				/* 39 task_cpu */
496 
497 	mutex_exit(p->p_lock);
498 	mutex_exit(proc_lock);
499 
500 	uvmspace_free(vm);
501 
502 	if (len == 0)
503 		goto out;
504 
505 	error = uiomove_frombuf(bf, len, uio);
506 out:
507 	free(bf, M_TEMP);
508 	return error;
509 }
510 
511 int
512 procfs_docpuinfo(struct lwp *curl, struct proc *p,
513     struct pfsnode *pfs, struct uio *uio)
514 {
515 	size_t len = LBFSZ;
516 	char *bf = NULL;
517 	int error;
518 
519 	do {
520 		if (bf)
521 			free(bf, M_TEMP);
522 		bf = malloc(len, M_TEMP, M_WAITOK);
523 	} while (procfs_getcpuinfstr(bf, &len) < 0);
524 
525 	if (len == 0) {
526 		error = 0;
527 		goto done;
528 	}
529 
530 	error = uiomove_frombuf(bf, len, uio);
531 done:
532 	free(bf, M_TEMP);
533 	return error;
534 }
535 
536 int
537 procfs_douptime(struct lwp *curl, struct proc *p,
538     struct pfsnode *pfs, struct uio *uio)
539 {
540 	char *bf;
541 	int len;
542 	struct timeval runtime;
543 	u_int64_t idle;
544 	int error = 0;
545 
546 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
547 
548 	microuptime(&runtime);
549 	idle = curcpu()->ci_schedstate.spc_cp_time[CP_IDLE];
550 	len = snprintf(bf, LBFSZ,
551 	    "%lld.%02lu %" PRIu64 ".%02" PRIu64 "\n",
552 	    (long long)runtime.tv_sec, (long)runtime.tv_usec / 10000,
553 	    idle / hz, (((idle % hz) * 100) / hz) % 100);
554 
555 	if (len == 0)
556 		goto out;
557 
558 	error = uiomove_frombuf(bf, len, uio);
559 out:
560 	free(bf, M_TEMP);
561 	return error;
562 }
563 
564 static int
565 procfs_format_sfs(char **mtab, size_t *mlen, char *buf, size_t blen,
566     const struct statvfs *sfs, struct lwp *curl, int suser)
567 {
568 	const char *fsname;
569 
570 	/* Linux uses different names for some filesystems */
571 	fsname = sfs->f_fstypename;
572 	if (strcmp(fsname, "procfs") == 0)
573 		fsname = "proc";
574 	else if (strcmp(fsname, "ext2fs") == 0)
575 		fsname = "ext2";
576 
577 	blen = snprintf(buf, blen, "%s %s %s %s%s%s%s%s%s 0 0\n",
578 	    sfs->f_mntfromname, sfs->f_mntonname, fsname,
579 	    (sfs->f_flag & ST_RDONLY) ? "ro" : "rw",
580 	    (sfs->f_flag & ST_NOSUID) ? ",nosuid" : "",
581 	    (sfs->f_flag & ST_NOEXEC) ? ",noexec" : "",
582 	    (sfs->f_flag & ST_NODEV) ? ",nodev" : "",
583 	    (sfs->f_flag & ST_SYNCHRONOUS) ? ",sync" : "",
584 	    (sfs->f_flag & ST_NOATIME) ? ",noatime" : "");
585 
586 	*mtab = realloc(*mtab, *mlen + blen, M_TEMP, M_WAITOK);
587 	memcpy(*mtab + *mlen, buf, blen);
588 	*mlen += blen;
589 	return sfs->f_mntonname[0] == '/' && sfs->f_mntonname[1] == '\0';
590 }
591 
592 int
593 procfs_domounts(struct lwp *curl, struct proc *p,
594     struct pfsnode *pfs, struct uio *uio)
595 {
596 	char *bf, *mtab = NULL;
597 	size_t mtabsz = 0;
598 	struct mount *mp, *nmp;
599 	int error = 0, root = 0;
600 	struct cwdinfo *cwdi = curl->l_proc->p_cwdi;
601 
602 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
603 
604 	mutex_enter(&mountlist_lock);
605 	for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
606 		struct statvfs sfs;
607 
608 		if (vfs_busy(mp, &nmp))
609 			continue;
610 
611 		if ((error = dostatvfs(mp, &sfs, curl, MNT_WAIT, 0)) == 0)
612 			root |= procfs_format_sfs(&mtab, &mtabsz, bf, LBFSZ,
613 			    &sfs, curl, 0);
614 
615 		vfs_unbusy(mp, false, &nmp);
616 	}
617 	mutex_exit(&mountlist_lock);
618 
619 	/*
620 	 * If we are inside a chroot that is not itself a mount point,
621 	 * fake a root entry.
622 	 */
623 	if (!root && cwdi->cwdi_rdir)
624 		(void)procfs_format_sfs(&mtab, &mtabsz, bf, LBFSZ,
625 		    &cwdi->cwdi_rdir->v_mount->mnt_stat, curl, 1);
626 
627 	free(bf, M_TEMP);
628 
629 	if (mtabsz > 0) {
630 		error = uiomove_frombuf(mtab, mtabsz, uio);
631 		free(mtab, M_TEMP);
632 	}
633 
634 	return error;
635 }
636 
637 /*
638  * Linux compatible /proc/version. Only active when the -o linux
639  * mountflag is used.
640  */
641 int
642 procfs_doversion(struct lwp *curl, struct proc *p,
643     struct pfsnode *pfs, struct uio *uio)
644 {
645 	char *bf;
646 	char lostype[20], losrelease[20], lversion[80];
647 	const char *postype, *posrelease, *pversion;
648 	const char *emulname = curlwp->l_proc->p_emul->e_name;
649 	int len;
650 	int error = 0;
651 	int nm[4];
652 	size_t buflen;
653 
654 	CTASSERT(EMUL_LINUX_KERN_OSTYPE == EMUL_LINUX32_KERN_OSTYPE);
655 	CTASSERT(EMUL_LINUX_KERN_OSRELEASE == EMUL_LINUX32_KERN_OSRELEASE);
656 	CTASSERT(EMUL_LINUX_KERN_VERSION == EMUL_LINUX32_KERN_VERSION);
657 
658 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
659 
660 	sysctl_lock(false);
661 
662 	if (strncmp(emulname, "linux", 5) == 0) {
663 		/*
664 		 * Lookup the emulation ostype, osrelease, and version.
665 		 * Since compat_linux and compat_linux32 can be built as
666 		 * modules, we use sysctl to obtain the values instead of
667 		 * using the symbols directly.
668 		 */
669 
670 		if (strcmp(emulname, "linux32") == 0) {
671 			nm[0] = CTL_EMUL;
672 			nm[1] = EMUL_LINUX32;
673 			nm[2] = EMUL_LINUX32_KERN;
674 		} else {
675 			nm[0] = CTL_EMUL;
676 			nm[1] = EMUL_LINUX;
677 			nm[2] = EMUL_LINUX_KERN;
678 		}
679 
680 		nm[3] = EMUL_LINUX_KERN_OSTYPE;
681 		buflen = sizeof(lostype);
682 		error = sysctl_dispatch(nm, __arraycount(nm),
683 		    lostype, &buflen,
684 		    NULL, 0, NULL, NULL, NULL);
685 		if (error)
686 			goto out;
687 
688 		nm[3] = EMUL_LINUX_KERN_OSRELEASE;
689 		buflen = sizeof(losrelease);
690 		error = sysctl_dispatch(nm, __arraycount(nm),
691 		    losrelease, &buflen,
692 		    NULL, 0, NULL, NULL, NULL);
693 		if (error)
694 			goto out;
695 
696 		nm[3] = EMUL_LINUX_KERN_VERSION;
697 		buflen = sizeof(lversion);
698 		error = sysctl_dispatch(nm, __arraycount(nm),
699 		    lversion, &buflen,
700 		    NULL, 0, NULL, NULL, NULL);
701 		if (error)
702 			goto out;
703 
704 		postype = lostype;
705 		posrelease = losrelease;
706 		pversion = lversion;
707 	} else {
708 		postype = ostype;
709 		posrelease = osrelease;
710 		strlcpy(lversion, version, sizeof(lversion));
711 		if (strchr(lversion, '\n'))
712 			*strchr(lversion, '\n') = '\0';
713 		pversion = lversion;
714 	}
715 
716 	len = snprintf(bf, LBFSZ,
717 		"%s version %s (%s@localhost) (gcc version %s) %s\n",
718 		postype, posrelease, emulname,
719 #ifdef __VERSION__
720 		__VERSION__,
721 #else
722 		"unknown",
723 #endif
724 		pversion);
725 
726 	if (len == 0)
727 		goto out;
728 
729 	error = uiomove_frombuf(bf, len, uio);
730 out:
731 	free(bf, M_TEMP);
732 	sysctl_unlock();
733 	return error;
734 }
735