xref: /netbsd-src/sys/miscfs/procfs/procfs_linux.c (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /*      $NetBSD: procfs_linux.c,v 1.76 2019/09/07 19:08:28 chs 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 1.76 2019/09/07 19:08:28 chs 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 proc *p, struct vm_map *map, unsigned long *stext,
79     unsigned long *etext, unsigned long *sstack)
80 {
81 	struct vm_map_entry *entry;
82 
83 	*stext = 0;
84 	*etext = 0;
85 	*sstack = 0;
86 
87 	vm_map_lock_read(map);
88 
89 	for (entry = map->header.next; entry != &map->header;
90 	    entry = entry->next) {
91 		if (UVM_ET_ISSUBMAP(entry))
92 			continue;
93 		/* assume text is the first entry */
94 		if (*stext == *etext) {
95 			*stext = entry->start;
96 			*etext = entry->end;
97 			break;
98 		}
99 	}
100 #if defined(LINUX_USRSTACK32) && defined(USRSTACK32)
101 	if (strcmp(p->p_emul->e_name, "linux32") == 0 &&
102 	    LINUX_USRSTACK32 < USRSTACK32)
103 		*sstack = (unsigned long)LINUX_USRSTACK32;
104 	else
105 #endif
106 #ifdef LINUX_USRSTACK
107 	if (strcmp(p->p_emul->e_name, "linux") == 0 &&
108 	    LINUX_USRSTACK < USRSTACK)
109 		*sstack = (unsigned long)LINUX_USRSTACK;
110 	else
111 #endif
112 #ifdef	USRSTACK32
113 	if (strstr(p->p_emul->e_name, "32") != NULL)
114 		*sstack = (unsigned long)USRSTACK32;
115 	else
116 #endif
117 		*sstack = (unsigned long)USRSTACK;
118 
119 	/*
120 	 * jdk 1.6 compares low <= addr && addr < high
121 	 * if we put addr == high, then the test fails
122 	 * so eat one page.
123 	 */
124 	*sstack -= PAGE_SIZE;
125 
126 	vm_map_unlock_read(map);
127 }
128 
129 /*
130  * Linux compatible /proc/meminfo. Only active when the -o linux
131  * mountflag is used.
132  */
133 int
134 procfs_domeminfo(struct lwp *curl, struct proc *p,
135     struct pfsnode *pfs, struct uio *uio)
136 {
137 	char *bf;
138 	int len;
139 	int error = 0;
140 
141 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
142 
143 	len = snprintf(bf, LBFSZ,
144 		"        total:    used:    free:  shared: buffers: cached:\n"
145 		"Mem:  %8lu %8lu %8lu %8lu %8lu %8lu\n"
146 		"Swap: %8lu %8lu %8lu\n"
147 		"MemTotal:  %8lu kB\n"
148 		"MemFree:   %8lu kB\n"
149 		"MemShared: %8lu kB\n"
150 		"Buffers:   %8lu kB\n"
151 		"Cached:    %8lu kB\n"
152 		"SwapTotal: %8lu kB\n"
153 		"SwapFree:  %8lu kB\n",
154 		PGTOB(uvmexp.npages),
155 		PGTOB(uvmexp.npages - uvmexp.free),
156 		PGTOB(uvmexp.free),
157 		0L,
158 		PGTOB(uvmexp.filepages),
159 		PGTOB(uvmexp.anonpages + uvmexp.filepages + uvmexp.execpages),
160 		PGTOB(uvmexp.swpages),
161 		PGTOB(uvmexp.swpginuse),
162 		PGTOB(uvmexp.swpages - uvmexp.swpginuse),
163 		PGTOKB(uvmexp.npages),
164 		PGTOKB(uvmexp.free),
165 		0L,
166 		PGTOKB(uvmexp.filepages),
167 		PGTOKB(uvmexp.anonpages + uvmexp.filepages + uvmexp.execpages),
168 		PGTOKB(uvmexp.swpages),
169 		PGTOKB(uvmexp.swpages - uvmexp.swpginuse));
170 
171 	if (len == 0)
172 		goto out;
173 
174 	error = uiomove_frombuf(bf, len, uio);
175 out:
176 	free(bf, M_TEMP);
177 	return error;
178 }
179 
180 /*
181  * Linux compatible /proc/devices. Only active when the -o linux
182  * mountflag is used.
183  */
184 int
185 procfs_dodevices(struct lwp *curl, struct proc *p,
186     struct pfsnode *pfs, struct uio *uio)
187 {
188 	char *bf;
189 	int offset = 0;
190 	int i, error = ENAMETOOLONG;
191 
192 	/* XXX elad - may need filtering. */
193 
194 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
195 
196 	offset += snprintf(&bf[offset], LBFSZ - offset, "Character devices:\n");
197 	if (offset >= LBFSZ)
198 		goto out;
199 
200 	mutex_enter(&device_lock);
201 	for (i = 0; i < max_devsw_convs; i++) {
202 		if ((devsw_conv[i].d_name == NULL) ||
203 		    (devsw_conv[i].d_cmajor == -1))
204 			continue;
205 
206 		offset += snprintf(&bf[offset], LBFSZ - offset,
207 		    "%3d %s\n", devsw_conv[i].d_cmajor, devsw_conv[i].d_name);
208 		if (offset >= LBFSZ) {
209 			mutex_exit(&device_lock);
210 			goto out;
211 		}
212 	}
213 
214 	offset += snprintf(&bf[offset], LBFSZ - offset, "\nBlock devices:\n");
215 	if (offset >= LBFSZ) {
216 		mutex_exit(&device_lock);
217 		goto out;
218 	}
219 
220 	for (i = 0; i < max_devsw_convs; i++) {
221 		if ((devsw_conv[i].d_name == NULL) ||
222 		    (devsw_conv[i].d_bmajor == -1))
223 			continue;
224 
225 		offset += snprintf(&bf[offset], LBFSZ - offset,
226 		    "%3d %s\n", devsw_conv[i].d_bmajor, devsw_conv[i].d_name);
227 		if (offset >= LBFSZ) {
228 			mutex_exit(&device_lock);
229 			goto out;
230 		}
231 	}
232 	mutex_exit(&device_lock);
233 
234 	error = uiomove_frombuf(bf, offset, uio);
235 out:
236 	free(bf, M_TEMP);
237 	return error;
238 }
239 
240 /*
241  * Linux compatible /proc/stat. Only active when the -o linux
242  * mountflag is used.
243  */
244 int
245 procfs_docpustat(struct lwp *curl, struct proc *p,
246     struct pfsnode *pfs, struct uio *uio)
247 {
248 	char		*bf;
249 	int	 	 error;
250 	int	 	 len;
251 #if defined(MULTIPROCESSOR)
252         struct cpu_info *ci;
253         CPU_INFO_ITERATOR cii;
254 #endif
255 	int	 	 i;
256 	uint64_t	nintr;
257 	uint64_t	nswtch;
258 
259 	error = ENAMETOOLONG;
260 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
261 
262 	len = snprintf(bf, LBFSZ,
263 		"cpu %" PRIu64 " %" PRIu64 " %" PRIu64 " %" PRIu64 "\n",
264 		curcpu()->ci_schedstate.spc_cp_time[CP_USER],
265 		curcpu()->ci_schedstate.spc_cp_time[CP_NICE],
266 		curcpu()->ci_schedstate.spc_cp_time[CP_SYS] /*+ [CP_INTR]*/,
267 		curcpu()->ci_schedstate.spc_cp_time[CP_IDLE]);
268 	if (len == 0)
269 		goto out;
270 
271 #if defined(MULTIPROCESSOR)
272 #define ALLCPUS	CPU_INFO_FOREACH(cii, ci)
273 #define CPUNAME	ci
274 #else
275 #define ALLCPUS	; i < 1 ;
276 #define CPUNAME	curcpu()
277 #endif
278 
279 	i = 0;
280 	nintr = 0;
281 	nswtch = 0;
282 	for (ALLCPUS) {
283 		len += snprintf(&bf[len], LBFSZ - len,
284 			"cpu%d %" PRIu64 " %" PRIu64 " %" PRIu64 " %" PRIu64
285 			"\n", i,
286 			CPUNAME->ci_schedstate.spc_cp_time[CP_USER],
287 			CPUNAME->ci_schedstate.spc_cp_time[CP_NICE],
288 			CPUNAME->ci_schedstate.spc_cp_time[CP_SYS],
289 			CPUNAME->ci_schedstate.spc_cp_time[CP_IDLE]);
290 		if (len >= LBFSZ)
291 			goto out;
292 		i += 1;
293 		nintr += CPUNAME->ci_data.cpu_nintr;
294 		nswtch += CPUNAME->ci_data.cpu_nswtch;
295 	}
296 
297 	len += snprintf(&bf[len], LBFSZ - len,
298 			"disk 0 0 0 0\n"
299 			"page %u %u\n"
300 			"swap %u %u\n"
301 			"intr %"PRIu64"\n"
302 			"ctxt %"PRIu64"\n"
303 			"btime %"PRId64"\n",
304 			uvmexp.pageins, uvmexp.pdpageouts,
305 			uvmexp.pgswapin, uvmexp.pgswapout,
306 			nintr,
307 			nswtch,
308 			boottime.tv_sec);
309 	if (len >= LBFSZ)
310 		goto out;
311 
312 	error = uiomove_frombuf(bf, len, uio);
313 out:
314 	free(bf, M_TEMP);
315 	return error;
316 }
317 
318 /*
319  * Linux compatible /proc/loadavg. Only active when the -o linux
320  * mountflag is used.
321  */
322 int
323 procfs_doloadavg(struct lwp *curl, struct proc *p,
324     struct pfsnode *pfs, struct uio *uio)
325 {
326 	char	*bf;
327 	int 	 error;
328 	int 	 len;
329 
330 	error = ENAMETOOLONG;
331 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
332 
333 	averunnable.fscale = FSCALE;
334 	len = snprintf(bf, LBFSZ,
335 	        "%d.%02d %d.%02d %d.%02d %d/%d %d\n",
336 		(int)(averunnable.ldavg[0] / averunnable.fscale),
337 		(int)(averunnable.ldavg[0] * 100 / averunnable.fscale % 100),
338 		(int)(averunnable.ldavg[1] / averunnable.fscale),
339 		(int)(averunnable.ldavg[1] * 100 / averunnable.fscale % 100),
340 		(int)(averunnable.ldavg[2] / averunnable.fscale),
341 		(int)(averunnable.ldavg[2] * 100 / averunnable.fscale % 100),
342 		1,		/* number of ONPROC processes */
343 		nprocs,
344 		30000);		/* last pid */
345 	if (len == 0)
346 		goto out;
347 
348 	error = uiomove_frombuf(bf, len, uio);
349 out:
350 	free(bf, M_TEMP);
351 	return error;
352 }
353 
354 /*
355  * Linux compatible /proc/<pid>/statm. Only active when the -o linux
356  * mountflag is used.
357  */
358 int
359 procfs_do_pid_statm(struct lwp *curl, struct lwp *l,
360     struct pfsnode *pfs, struct uio *uio)
361 {
362 	struct vmspace	*vm;
363 	struct proc	*p = l->l_proc;
364 	char		*bf;
365 	int	 	 error;
366 	int	 	 len;
367 	struct kinfo_proc2 ki;
368 
369 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
370 
371 	/* XXX - we use values from vmspace, since dsl says that ru figures
372 	   are always 0 except for zombies. See kvm_proc.c::kvm_getproc2() */
373 	if ((error = proc_vmspace_getref(p, &vm)) != 0) {
374 		goto out;
375 	}
376 
377 	mutex_enter(proc_lock);
378 	mutex_enter(p->p_lock);
379 
380 	/* retrieve RSS size */
381 	memset(&ki, 0, sizeof(ki));
382 	fill_kproc2(p, &ki, false, false);
383 
384 	mutex_exit(p->p_lock);
385 	mutex_exit(proc_lock);
386 
387 	uvmspace_free(vm);
388 
389 	len = snprintf(bf, LBFSZ,
390 	        "%lu %lu %lu %lu %lu %lu %lu\n",
391 		(unsigned long)(ki.p_vm_msize),	/* size */
392 		(unsigned long)(ki.p_vm_rssize),/* resident */
393 		(unsigned long)(ki.p_uru_ixrss),/* shared */
394 		(unsigned long)(ki.p_vm_tsize),	/* text */
395 		(unsigned long) 0,		/* library (unused) */
396 		(unsigned long)(ki.p_vm_dsize + ki.p_vm_ssize),	/* data+stack */
397 		(unsigned long) 0);		/* dirty */
398 
399 	if (len == 0)
400 		goto out;
401 
402 	error = uiomove_frombuf(bf, len, uio);
403 out:
404 	free(bf, M_TEMP);
405 	return error;
406 }
407 
408 #define UTIME2TICKS(s,u)	(((uint64_t)(s) * 1000000 + (u)) / 10000)
409 
410 /*
411  * Linux compatible /proc/<pid>/stat. Only active when the -o linux
412  * mountflag is used.
413  */
414 int
415 procfs_do_pid_stat(struct lwp *curl, struct lwp *l,
416     struct pfsnode *pfs, struct uio *uio)
417 {
418 	char *bf;
419 	struct proc *p = l->l_proc;
420 	int len;
421 	struct rusage *cru = &p->p_stats->p_cru;
422 	unsigned long stext = 0, etext = 0, sstack = 0;
423 	struct timeval rt;
424 	struct vmspace	*vm;
425 	struct kinfo_proc2 ki;
426 	int error;
427 
428 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
429 
430 	if ((error = proc_vmspace_getref(p, &vm)) != 0) {
431 		goto out;
432 	}
433 
434 	get_proc_size_info(p, &vm->vm_map, &stext, &etext, &sstack);
435 
436 	mutex_enter(proc_lock);
437 	mutex_enter(p->p_lock);
438 
439 	memset(&ki, 0, sizeof(ki));
440 	fill_kproc2(p, &ki, false, false);
441 	calcru(p, NULL, NULL, NULL, &rt);
442 
443 	len = snprintf(bf, LBFSZ,
444 	    "%d (%s) %c %d %d %d %u %d "
445 	    "%u "
446 	    "%"PRIu64" %lu %"PRIu64" %lu %"PRIu64" %"PRIu64" %"PRIu64" %"PRIu64" "
447 	    "%d %d %"PRIu64" "
448 	    "%lld %"PRIu64" %"PRId64" %lu %"PRIu64" "
449 	    "%lu %lu %lu "
450 	    "%u %u "
451 	    "%u %u %u %u "
452 	    "%"PRIu64" %"PRIu64" %"PRIu64" %d %"PRIu64"\n",
453 
454 	    ki.p_pid,						/* 1 pid */
455 	    ki.p_comm,						/* 2 tcomm */
456 	    "0RRSTZXR8"[(ki.p_stat > 8) ? 0 : (int)ki.p_stat],	/* 3 state */
457 	    ki.p_ppid,						/* 4 ppid */
458 	    ki.p__pgid,						/* 5 pgrp */
459 	    ki.p_sid,						/* 6 sid */
460 	    (ki.p_tdev != (uint32_t)NODEV) ? ki.p_tdev : 0,	/* 7 tty_nr */
461 	    ki.p_tpgid,						/* 8 tty_pgrp */
462 
463 	    ki.p_flag,						/* 9 flags */
464 
465 	    ki.p_uru_minflt,					/* 10 min_flt */
466 	    cru->ru_minflt,
467 	    ki.p_uru_majflt,					/* 12 maj_flt */
468 	    cru->ru_majflt,
469 	    UTIME2TICKS(ki.p_uutime_sec, ki.p_uutime_usec),	/* 14 utime */
470 	    UTIME2TICKS(ki.p_ustime_sec, ki.p_ustime_usec),	/* 15 stime */
471 	    UTIME2TICKS(cru->ru_utime.tv_sec, cru->ru_utime.tv_usec), /* 16 cutime */
472 	    UTIME2TICKS(cru->ru_stime.tv_sec, cru->ru_stime.tv_usec), /* 17 cstime */
473 
474 	    ki.p_priority,				/* XXX: 18 priority */
475 	    ki.p_nice - NZERO,				/* 19 nice */
476 	    ki.p_nlwps,					/* 20 num_threads */
477 
478 	    (long long)rt.tv_sec,
479 	    UTIME2TICKS(ki.p_ustart_sec, ki.p_ustart_usec), /* 22 start_time */
480 	    ki.p_vm_msize,				/* 23 vsize */
481 	    PGTOKB(ki.p_vm_rssize),			/* 24 rss */
482 	    p->p_rlimit[RLIMIT_RSS].rlim_cur,		/* 25 rsslim */
483 
484 	    stext,					/* 26 start_code */
485 	    etext,					/* 27 end_code */
486 	    sstack,					/* 28 start_stack */
487 
488 	    0,						/* XXX: 29 esp */
489 	    0,						/* XXX: 30 eip */
490 
491 	    ki.p_siglist.__bits[0],			/* XXX: 31 pending */
492 	    0,						/* XXX: 32 blocked */
493 	    ki.p_sigignore.__bits[0],		/* 33 sigign */
494 	    ki.p_sigcatch.__bits[0],		/* 34 sigcatch */
495 
496 	    ki.p_wchan,					/* 35 wchan */
497 	    ki.p_uru_nvcsw,
498 	    ki.p_uru_nivcsw,
499 	    ki.p_exitsig,				/* 38 exit_signal */
500 	    ki.p_cpuid);				/* 39 task_cpu */
501 
502 	mutex_exit(p->p_lock);
503 	mutex_exit(proc_lock);
504 
505 	uvmspace_free(vm);
506 
507 	if (len == 0)
508 		goto out;
509 
510 	error = uiomove_frombuf(bf, len, uio);
511 out:
512 	free(bf, M_TEMP);
513 	return error;
514 }
515 
516 int
517 procfs_docpuinfo(struct lwp *curl, struct proc *p,
518     struct pfsnode *pfs, struct uio *uio)
519 {
520 	size_t len = LBFSZ;
521 	char *bf = NULL;
522 	int error;
523 
524 	do {
525 		if (bf)
526 			free(bf, M_TEMP);
527 		bf = malloc(len, M_TEMP, M_WAITOK);
528 	} while (procfs_getcpuinfstr(bf, &len) < 0);
529 
530 	if (len == 0) {
531 		error = 0;
532 		goto done;
533 	}
534 
535 	error = uiomove_frombuf(bf, len, uio);
536 done:
537 	free(bf, M_TEMP);
538 	return error;
539 }
540 
541 int
542 procfs_douptime(struct lwp *curl, struct proc *p,
543     struct pfsnode *pfs, struct uio *uio)
544 {
545 	char *bf;
546 	int len;
547 	struct timeval runtime;
548 	u_int64_t idle;
549 	int error = 0;
550 
551 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
552 
553 	microuptime(&runtime);
554 	idle = curcpu()->ci_schedstate.spc_cp_time[CP_IDLE];
555 	len = snprintf(bf, LBFSZ,
556 	    "%lld.%02lu %" PRIu64 ".%02" PRIu64 "\n",
557 	    (long long)runtime.tv_sec, (long)runtime.tv_usec / 10000,
558 	    idle / hz, (((idle % hz) * 100) / hz) % 100);
559 
560 	if (len == 0)
561 		goto out;
562 
563 	error = uiomove_frombuf(bf, len, uio);
564 out:
565 	free(bf, M_TEMP);
566 	return error;
567 }
568 
569 static int
570 procfs_format_sfs(char **mtab, size_t *mlen, char *buf, size_t blen,
571     const struct statvfs *sfs, struct lwp *curl, int suser)
572 {
573 	const char *fsname;
574 
575 	/* Linux uses different names for some filesystems */
576 	fsname = sfs->f_fstypename;
577 	if (strcmp(fsname, "procfs") == 0)
578 		fsname = "proc";
579 	else if (strcmp(fsname, "ext2fs") == 0)
580 		fsname = "ext2";
581 
582 	blen = snprintf(buf, blen, "%s %s %s %s%s%s%s%s%s 0 0\n",
583 	    sfs->f_mntfromname, sfs->f_mntonname, fsname,
584 	    (sfs->f_flag & ST_RDONLY) ? "ro" : "rw",
585 	    (sfs->f_flag & ST_NOSUID) ? ",nosuid" : "",
586 	    (sfs->f_flag & ST_NOEXEC) ? ",noexec" : "",
587 	    (sfs->f_flag & ST_NODEV) ? ",nodev" : "",
588 	    (sfs->f_flag & ST_SYNCHRONOUS) ? ",sync" : "",
589 	    (sfs->f_flag & ST_NOATIME) ? ",noatime" : "");
590 
591 	*mtab = realloc(*mtab, *mlen + blen, M_TEMP, M_WAITOK);
592 	memcpy(*mtab + *mlen, buf, blen);
593 	*mlen += blen;
594 	return sfs->f_mntonname[0] == '/' && sfs->f_mntonname[1] == '\0';
595 }
596 
597 int
598 procfs_domounts(struct lwp *curl, struct proc *p,
599     struct pfsnode *pfs, struct uio *uio)
600 {
601 	char *bf, *mtab = NULL;
602 	size_t mtabsz = 0;
603 	mount_iterator_t *iter;
604 	struct mount *mp;
605 	int error = 0, root = 0;
606 	struct cwdinfo *cwdi = curl->l_proc->p_cwdi;
607 
608 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
609 
610 	mountlist_iterator_init(&iter);
611 	while ((mp = mountlist_iterator_next(iter)) != NULL) {
612 		struct statvfs sfs;
613 
614 		if ((error = dostatvfs(mp, &sfs, curl, MNT_WAIT, 0)) == 0)
615 			root |= procfs_format_sfs(&mtab, &mtabsz, bf, LBFSZ,
616 			    &sfs, curl, 0);
617 	}
618 	mountlist_iterator_destroy(iter);
619 
620 	/*
621 	 * If we are inside a chroot that is not itself a mount point,
622 	 * fake a root entry.
623 	 */
624 	if (!root && cwdi->cwdi_rdir)
625 		(void)procfs_format_sfs(&mtab, &mtabsz, bf, LBFSZ,
626 		    &cwdi->cwdi_rdir->v_mount->mnt_stat, curl, 1);
627 
628 	free(bf, M_TEMP);
629 
630 	if (mtabsz > 0) {
631 		error = uiomove_frombuf(mtab, mtabsz, uio);
632 		free(mtab, M_TEMP);
633 	}
634 
635 	return error;
636 }
637 
638 /*
639  * Linux compatible /proc/version. Only active when the -o linux
640  * mountflag is used.
641  */
642 int
643 procfs_doversion(struct lwp *curl, struct proc *p,
644     struct pfsnode *pfs, struct uio *uio)
645 {
646 	char *bf;
647 	char lostype[20], losrelease[20], lversion[80];
648 	const char *postype, *posrelease, *pversion;
649 	const char *emulname = curlwp->l_proc->p_emul->e_name;
650 	int len;
651 	int error = 0;
652 	int nm[4];
653 	size_t buflen;
654 
655 	CTASSERT(EMUL_LINUX_KERN_OSTYPE == EMUL_LINUX32_KERN_OSTYPE);
656 	CTASSERT(EMUL_LINUX_KERN_OSRELEASE == EMUL_LINUX32_KERN_OSRELEASE);
657 	CTASSERT(EMUL_LINUX_KERN_VERSION == EMUL_LINUX32_KERN_VERSION);
658 
659 	bf = malloc(LBFSZ, M_TEMP, M_WAITOK);
660 
661 	sysctl_lock(false);
662 
663 	if (strncmp(emulname, "linux", 5) == 0) {
664 		/*
665 		 * Lookup the emulation ostype, osrelease, and version.
666 		 * Since compat_linux and compat_linux32 can be built as
667 		 * modules, we use sysctl to obtain the values instead of
668 		 * using the symbols directly.
669 		 */
670 
671 		if (strcmp(emulname, "linux32") == 0) {
672 			nm[0] = CTL_EMUL;
673 			nm[1] = EMUL_LINUX32;
674 			nm[2] = EMUL_LINUX32_KERN;
675 		} else {
676 			nm[0] = CTL_EMUL;
677 			nm[1] = EMUL_LINUX;
678 			nm[2] = EMUL_LINUX_KERN;
679 		}
680 
681 		nm[3] = EMUL_LINUX_KERN_OSTYPE;
682 		buflen = sizeof(lostype);
683 		error = sysctl_dispatch(nm, __arraycount(nm),
684 		    lostype, &buflen,
685 		    NULL, 0, NULL, NULL, NULL);
686 		if (error)
687 			goto out;
688 
689 		nm[3] = EMUL_LINUX_KERN_OSRELEASE;
690 		buflen = sizeof(losrelease);
691 		error = sysctl_dispatch(nm, __arraycount(nm),
692 		    losrelease, &buflen,
693 		    NULL, 0, NULL, NULL, NULL);
694 		if (error)
695 			goto out;
696 
697 		nm[3] = EMUL_LINUX_KERN_VERSION;
698 		buflen = sizeof(lversion);
699 		error = sysctl_dispatch(nm, __arraycount(nm),
700 		    lversion, &buflen,
701 		    NULL, 0, NULL, NULL, NULL);
702 		if (error)
703 			goto out;
704 
705 		postype = lostype;
706 		posrelease = losrelease;
707 		pversion = lversion;
708 	} else {
709 		postype = ostype;
710 		posrelease = osrelease;
711 		strlcpy(lversion, version, sizeof(lversion));
712 		if (strchr(lversion, '\n'))
713 			*strchr(lversion, '\n') = '\0';
714 		pversion = lversion;
715 	}
716 
717 	len = snprintf(bf, LBFSZ,
718 		"%s version %s (%s@localhost) (gcc version %s) %s\n",
719 		postype, posrelease, emulname,
720 #ifdef __VERSION__
721 		__VERSION__,
722 #else
723 		"unknown",
724 #endif
725 		pversion);
726 
727 	if (len == 0)
728 		goto out;
729 
730 	error = uiomove_frombuf(bf, len, uio);
731 out:
732 	free(bf, M_TEMP);
733 	sysctl_unlock();
734 	return error;
735 }
736