]> bbs.cooldavid.org Git - net-next-2.6.git/blame - fs/proc/base.c
git://bbs.cooldavid.org / net-next-2.6.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Merge branch 'pdc-regression' into release
[net-next-2.6.git] / fs / proc / base.c
CommitLineData
1da177e4
LT		 1/*
2 * linux/fs/proc/base.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * proc base directory handling functions
7 *
8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
9 * Instead of using magical inumbers to determine the kind of object
10 * we allocate and fill in-core inodes upon lookup. They don't even
11 * go into icache. We cache the reference to task_struct upon lookup too.
12 * Eventually it should become a filesystem in its own. We don't use the
13 * rest of procfs anymore.
e070ad49
ML		 14 *
15 *
16 * Changelog:
17 * 17-Jan-2005
18 * Allan Bezerra
19 * Bruna Moreira <bruna.moreira@indt.org.br>
20 * Edjard Mota <edjard.mota@indt.org.br>
21 * Ilias Biris <ilias.biris@indt.org.br>
22 * Mauricio Lin <mauricio.lin@indt.org.br>
23 *
24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
25 *
26 * A new process specific entry (smaps) included in /proc. It shows the
27 * size of rss for each memory area. The maps entry lacks information
28 * about physical memory size (rss) for each mapped file, i.e.,
29 * rss information for executables and library files.
30 * This additional information is useful for any tools that need to know
31 * about physical memory consumption for a process specific library.
32 *
33 * Changelog:
34 * 21-Feb-2005
35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
36 * Pud inclusion in the page table walking.
37 *
38 * ChangeLog:
39 * 10-Mar-2005
40 * 10LE Instituto Nokia de Tecnologia - INdT:
41 * A better way to walks through the page table as suggested by Hugh Dickins.
42 *
43 * Simo Piiroinen <simo.piiroinen@nokia.com>:
44 * Smaps information related to shared, private, clean and dirty pages.
45 *
46 * Paul Mundt <paul.mundt@nokia.com>:
47 * Overall revision about smaps.
1da177e4
LT		 48 */
49
50#include <asm/uaccess.h>
51
1da177e4
LT		 52#include <linux/errno.h>
53#include <linux/time.h>
54#include <linux/proc_fs.h>
55#include <linux/stat.h>
5995477a 56#include <linux/task_io_accounting_ops.h>
1da177e4 57#include <linux/init.h>
16f7e0fe 58#include <linux/capability.h>
1da177e4 59#include <linux/file.h>
9f3acc31 60#include <linux/fdtable.h>
1da177e4
LT		 61#include <linux/string.h>
62#include <linux/seq_file.h>
63#include <linux/namei.h>
6b3286ed 64#include <linux/mnt_namespace.h>
1da177e4 65#include <linux/mm.h>
a63d83f4 66#include <linux/swap.h>
b835996f 67#include <linux/rcupdate.h>
1da177e4 68#include <linux/kallsyms.h>
2ec220e2 69#include <linux/stacktrace.h>
d85f50d5 70#include <linux/resource.h>
5096add8 71#include <linux/module.h>
1da177e4
LT		 72#include <linux/mount.h>
73#include <linux/security.h>
74#include <linux/ptrace.h>
0d094efe 75#include <linux/tracehook.h>
a424316c 76#include <linux/cgroup.h>
1da177e4
LT		 77#include <linux/cpuset.h>
78#include <linux/audit.h>
5addc5dd 79#include <linux/poll.h>
1651e14e 80#include <linux/nsproxy.h>
8ac773b4 81#include <linux/oom.h>
3cb4a0bb 82#include <linux/elf.h>
60347f67 83#include <linux/pid_namespace.h>
5ad4e53b 84#include <linux/fs_struct.h>
5a0e3ad6 85#include <linux/slab.h>
1da177e4
LT		 86#include "internal.h"
87
0f2fe20f
EB		 88/* NOTE:
89 * Implementing inode permission operations in /proc is almost
90 * certainly an error. Permission checks need to happen during
91 * each system call not at open time. The reason is that most of
92 * what we wish to check for permissions in /proc varies at runtime.
93 *
94 * The classic example of a problem is opening file descriptors
95 * in /proc for a task before it execs a suid executable.
96 */
97
1da177e4 98struct pid_entry {
1da177e4 99 char *name;
c5141e6d 100 int len;
1da177e4 101 mode_t mode;
c5ef1c42 102 const struct inode_operations *iop;
00977a59 103 const struct file_operations *fop;
20cdc894 104 union proc_op op;
1da177e4
LT		 105};
106
61a28784 107#define NOD(NAME, MODE, IOP, FOP, OP) { \
20cdc894 108 .name = (NAME), \
c5141e6d 109 .len = sizeof(NAME) - 1, \
20cdc894
EB		 110 .mode = MODE, \
111 .iop = IOP, \
112 .fop = FOP, \
113 .op = OP, \
114}
115
631f9c18
AD		 116#define DIR(NAME, MODE, iops, fops) \
117 NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} )
118#define LNK(NAME, get_link) \
61a28784 119 NOD(NAME, (S_IFLNK|S_IRWXUGO), \
20cdc894 120 &proc_pid_link_inode_operations, NULL, \
631f9c18
AD		 121 { .proc_get_link = get_link } )
122#define REG(NAME, MODE, fops) \
123 NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {})
124#define INF(NAME, MODE, read) \
61a28784 125 NOD(NAME, (S_IFREG|(MODE)), \
20cdc894 126 NULL, &proc_info_file_operations, \
631f9c18
AD		 127 { .proc_read = read } )
128#define ONE(NAME, MODE, show) \
be614086
EB		 129 NOD(NAME, (S_IFREG|(MODE)), \
130 NULL, &proc_single_file_operations, \
631f9c18 131 { .proc_show = show } )
1da177e4 132
aed54175
VN		 133/*
134 * Count the number of hardlinks for the pid_entry table, excluding the .
135 * and .. links.
136 */
137static unsigned int pid_entry_count_dirs(const struct pid_entry *entries,
138 unsigned int n)
139{
140 unsigned int i;
141 unsigned int count;
142
143 count = 0;
144 for (i = 0; i < n; ++i) {
145 if (S_ISDIR(entries[i].mode))
146 ++count;
147 }
148
149 return count;
150}
151
f7ad3c6b 152static int get_task_root(struct task_struct *task, struct path *root)
1da177e4 153{
7c2c7d99
HD		 154 int result = -ENOENT;
155
0494f6ec 156 task_lock(task);
f7ad3c6b
MS		 157 if (task->fs) {
158 get_fs_root(task->fs, root);
7c2c7d99
HD		 159 result = 0;
160 }
0494f6ec 161 task_unlock(task);
7c2c7d99 162 return result;
0494f6ec
MS		 163}
164
3dcd25f3 165static int proc_cwd_link(struct inode *inode, struct path *path)
0494f6ec 166{
99f89551 167 struct task_struct *task = get_proc_task(inode);
0494f6ec 168 int result = -ENOENT;
99f89551
EB		 169
170 if (task) {
f7ad3c6b
MS		 171 task_lock(task);
172 if (task->fs) {
173 get_fs_pwd(task->fs, path);
174 result = 0;
175 }
176 task_unlock(task);
99f89551
EB		 177 put_task_struct(task);
178 }
1da177e4
LT		 179 return result;
180}
181
3dcd25f3 182static int proc_root_link(struct inode *inode, struct path *path)
1da177e4 183{
99f89551 184 struct task_struct *task = get_proc_task(inode);
1da177e4 185 int result = -ENOENT;
99f89551
EB		 186
187 if (task) {
f7ad3c6b 188 result = get_task_root(task, path);
99f89551
EB		 189 put_task_struct(task);
190 }
1da177e4
LT		 191 return result;
192}
193
638fa202
RM		 194/*
195 * Return zero if current may access user memory in @task, -error if not.
196 */
197static int check_mem_permission(struct task_struct *task)
198{
199 /*
200 * A task can always look at itself, in case it chooses
201 * to use system calls instead of load instructions.
202 */
203 if (task == current)
204 return 0;
205
206 /*
207 * If current is actively ptrace'ing, and would also be
208 * permitted to freshly attach with ptrace now, permit it.
209 */
0d094efe
RM		 210 if (task_is_stopped_or_traced(task)) {
211 int match;
212 rcu_read_lock();
213 match = (tracehook_tracer_task(task) == current);
214 rcu_read_unlock();
215 if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
216 return 0;
217 }
638fa202
RM		 218
219 /*
220 * Noone else is allowed.
221 */
222 return -EPERM;
223}
1da177e4 224
831830b5
AV		 225struct mm_struct *mm_for_maps(struct task_struct *task)
226{
704b836c
ON		 227 struct mm_struct *mm;
228
229 if (mutex_lock_killable(&task->cred_guard_mutex))
230 return NULL;
00f89d21 231
704b836c
ON		 232 mm = get_task_mm(task);
233 if (mm && mm != current->mm &&
234 !ptrace_may_access(task, PTRACE_MODE_READ)) {
235 mmput(mm);
236 mm = NULL;
13f0feaf 237 }
704b836c
ON		 238 mutex_unlock(&task->cred_guard_mutex);
239
831830b5 240 return mm;
831830b5
AV		 241}
242
1da177e4
LT		 243static int proc_pid_cmdline(struct task_struct *task, char * buffer)
244{
245 int res = 0;
246 unsigned int len;
247 struct mm_struct *mm = get_task_mm(task);
248 if (!mm)
249 goto out;
250 if (!mm->arg_end)
251 goto out_mm; /* Shh! No looking before we're done */
252
253 len = mm->arg_end - mm->arg_start;
254
255 if (len > PAGE_SIZE)
256 len = PAGE_SIZE;
257
258 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
259
260 // If the nul at the end of args has been overwritten, then
261 // assume application is using setproctitle(3).
262 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
263 len = strnlen(buffer, res);
264 if (len < res) {
265 res = len;
266 } else {
267 len = mm->env_end - mm->env_start;
268 if (len > PAGE_SIZE - res)
269 len = PAGE_SIZE - res;
270 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
271 res = strnlen(buffer, res);
272 }
273 }
274out_mm:
275 mmput(mm);
276out:
277 return res;
278}
279
280static int proc_pid_auxv(struct task_struct *task, char *buffer)
281{
282 int res = 0;
283 struct mm_struct *mm = get_task_mm(task);
284 if (mm) {
285 unsigned int nwords = 0;
dfe6b7d9 286 do {
1da177e4 287 nwords += 2;
dfe6b7d9 288 } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
1da177e4
LT		 289 res = nwords * sizeof(mm->saved_auxv[0]);
290 if (res > PAGE_SIZE)
291 res = PAGE_SIZE;
292 memcpy(buffer, mm->saved_auxv, res);
293 mmput(mm);
294 }
295 return res;
296}
297
298
299#ifdef CONFIG_KALLSYMS
300/*
301 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
302 * Returns the resolved symbol. If that fails, simply return the address.
303 */
304static int proc_pid_wchan(struct task_struct *task, char *buffer)
305{
ffb45122 306 unsigned long wchan;
9281acea 307 char symname[KSYM_NAME_LEN];
1da177e4
LT		 308
309 wchan = get_wchan(task);
310
9d65cb4a 311 if (lookup_symbol_name(wchan, symname) < 0)
f83ce3e6
JE		 312 if (!ptrace_may_access(task, PTRACE_MODE_READ))
313 return 0;
314 else
315 return sprintf(buffer, "%lu", wchan);
9d65cb4a
AD		 316 else
317 return sprintf(buffer, "%s", symname);
1da177e4
LT		 318}
319#endif /* CONFIG_KALLSYMS */
320
2ec220e2
KC		 321#ifdef CONFIG_STACKTRACE
322
323#define MAX_STACK_TRACE_DEPTH 64
324
325static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns,
326 struct pid *pid, struct task_struct *task)
327{
328 struct stack_trace trace;
329 unsigned long *entries;
330 int i;
331
332 entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL);
333 if (!entries)
334 return -ENOMEM;
335
336 trace.nr_entries = 0;
337 trace.max_entries = MAX_STACK_TRACE_DEPTH;
338 trace.entries = entries;
339 trace.skip = 0;
340 save_stack_trace_tsk(task, &trace);
341
342 for (i = 0; i < trace.nr_entries; i++) {
343 seq_printf(m, "[<%p>] %pS\n",
344 (void *)entries[i], (void *)entries[i]);
345 }
346 kfree(entries);
347
348 return 0;
349}
350#endif
351
1da177e4
LT		 352#ifdef CONFIG_SCHEDSTATS
353/*
354 * Provides /proc/PID/schedstat
355 */
356static int proc_pid_schedstat(struct task_struct *task, char *buffer)
357{
172ba844 358 return sprintf(buffer, "%llu %llu %lu\n",
826e08b0
IM		 359 (unsigned long long)task->se.sum_exec_runtime,
360 (unsigned long long)task->sched_info.run_delay,
2d72376b 361 task->sched_info.pcount);
1da177e4
LT		 362}
363#endif
364
9745512c
AV		 365#ifdef CONFIG_LATENCYTOP
366static int lstats_show_proc(struct seq_file *m, void *v)
367{
368 int i;
13d77c37
HS		 369 struct inode *inode = m->private;
370 struct task_struct *task = get_proc_task(inode);
9745512c 371
13d77c37
HS		 372 if (!task)
373 return -ESRCH;
374 seq_puts(m, "Latency Top version : v0.1\n");
9745512c
AV		 375 for (i = 0; i < 32; i++) {
376 if (task->latency_record[i].backtrace[0]) {
377 int q;
378 seq_printf(m, "%i %li %li ",
379 task->latency_record[i].count,
380 task->latency_record[i].time,
381 task->latency_record[i].max);
382 for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
9c246247 383 char sym[KSYM_SYMBOL_LEN];
9745512c
AV		 384 char *c;
385 if (!task->latency_record[i].backtrace[q])
386 break;
387 if (task->latency_record[i].backtrace[q] == ULONG_MAX)
388 break;
389 sprint_symbol(sym, task->latency_record[i].backtrace[q]);
390 c = strchr(sym, '+');
391 if (c)
392 *c = 0;
393 seq_printf(m, "%s ", sym);
394 }
395 seq_printf(m, "\n");
396 }
397
398 }
13d77c37 399 put_task_struct(task);
9745512c
AV		 400 return 0;
401}
402
403static int lstats_open(struct inode *inode, struct file *file)
404{
13d77c37 405 return single_open(file, lstats_show_proc, inode);
d6643d12
HS		 406}
407
9745512c
AV		 408static ssize_t lstats_write(struct file *file, const char __user *buf,
409 size_t count, loff_t *offs)
410{
13d77c37 411 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
9745512c 412
13d77c37
HS		 413 if (!task)
414 return -ESRCH;
9745512c 415 clear_all_latency_tracing(task);
13d77c37 416 put_task_struct(task);
9745512c
AV		 417
418 return count;
419}
420
421static const struct file_operations proc_lstats_operations = {
422 .open = lstats_open,
423 .read = seq_read,
424 .write = lstats_write,
425 .llseek = seq_lseek,
13d77c37 426 .release = single_release,
9745512c
AV		 427};
428
429#endif
430
1da177e4
LT		 431static int proc_oom_score(struct task_struct *task, char *buffer)
432{
b95c35e7 433 unsigned long points = 0;
1da177e4 434
19c5d45a 435 read_lock(&tasklist_lock);
b95c35e7 436 if (pid_alive(task))
a63d83f4
DR		 437 points = oom_badness(task, NULL, NULL,
438 totalram_pages + total_swap_pages);
19c5d45a 439 read_unlock(&tasklist_lock);
1da177e4
LT		 440 return sprintf(buffer, "%lu\n", points);
441}
442
d85f50d5
NH		 443struct limit_names {
444 char *name;
445 char *unit;
446};
447
448static const struct limit_names lnames[RLIM_NLIMITS] = {
cff4edb5 449 [RLIMIT_CPU] = {"Max cpu time", "seconds"},
d85f50d5
NH		 450 [RLIMIT_FSIZE] = {"Max file size", "bytes"},
451 [RLIMIT_DATA] = {"Max data size", "bytes"},
452 [RLIMIT_STACK] = {"Max stack size", "bytes"},
453 [RLIMIT_CORE] = {"Max core file size", "bytes"},
454 [RLIMIT_RSS] = {"Max resident set", "bytes"},
455 [RLIMIT_NPROC] = {"Max processes", "processes"},
456 [RLIMIT_NOFILE] = {"Max open files", "files"},
457 [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
458 [RLIMIT_AS] = {"Max address space", "bytes"},
459 [RLIMIT_LOCKS] = {"Max file locks", "locks"},
460 [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
461 [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
462 [RLIMIT_NICE] = {"Max nice priority", NULL},
463 [RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
8808117c 464 [RLIMIT_RTTIME] = {"Max realtime timeout", "us"},
d85f50d5
NH		 465};
466
467/* Display limits for a process */
468static int proc_pid_limits(struct task_struct *task, char *buffer)
469{
470 unsigned int i;
471 int count = 0;
472 unsigned long flags;
473 char *bufptr = buffer;
474
475 struct rlimit rlim[RLIM_NLIMITS];
476
a6bebbc8 477 if (!lock_task_sighand(task, &flags))
d85f50d5 478 return 0;
d85f50d5
NH		 479 memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
480 unlock_task_sighand(task, &flags);
d85f50d5
NH		 481
482 /*
483 * print the file header
484 */
485 count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
486 "Limit", "Soft Limit", "Hard Limit", "Units");
487
488 for (i = 0; i < RLIM_NLIMITS; i++) {
489 if (rlim[i].rlim_cur == RLIM_INFINITY)
490 count += sprintf(&bufptr[count], "%-25s %-20s ",
491 lnames[i].name, "unlimited");
492 else
493 count += sprintf(&bufptr[count], "%-25s %-20lu ",
494 lnames[i].name, rlim[i].rlim_cur);
495
496 if (rlim[i].rlim_max == RLIM_INFINITY)
497 count += sprintf(&bufptr[count], "%-20s ", "unlimited");
498 else
499 count += sprintf(&bufptr[count], "%-20lu ",
500 rlim[i].rlim_max);
501
502 if (lnames[i].unit)
503 count += sprintf(&bufptr[count], "%-10s\n",
504 lnames[i].unit);
505 else
506 count += sprintf(&bufptr[count], "\n");
507 }
508
509 return count;
510}
511
ebcb6734
RM		 512#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
513static int proc_pid_syscall(struct task_struct *task, char *buffer)
514{
515 long nr;
516 unsigned long args[6], sp, pc;
517
518 if (task_current_syscall(task, &nr, args, 6, &sp, &pc))
519 return sprintf(buffer, "running\n");
520
521 if (nr < 0)
522 return sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc);
523
524 return sprintf(buffer,
525 "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
526 nr,
527 args[0], args[1], args[2], args[3], args[4], args[5],
528 sp, pc);
529}
530#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
531
1da177e4
LT		 532/************************************************************************/
533/* Here the fs part begins */
534/************************************************************************/
535
536/* permission checks */
778c1144 537static int proc_fd_access_allowed(struct inode *inode)
1da177e4 538{
778c1144
EB		 539 struct task_struct *task;
540 int allowed = 0;
df26c40e
EB		 541 /* Allow access to a task's file descriptors if it is us or we
542 * may use ptrace attach to the process and find out that
543 * information.
778c1144
EB		 544 */
545 task = get_proc_task(inode);
df26c40e 546 if (task) {
006ebb40 547 allowed = ptrace_may_access(task, PTRACE_MODE_READ);
778c1144 548 put_task_struct(task);
df26c40e 549 }
778c1144 550 return allowed;
1da177e4
LT		 551}
552
6d76fa58
LT		 553static int proc_setattr(struct dentry *dentry, struct iattr *attr)
554{
555 int error;
556 struct inode *inode = dentry->d_inode;
557
558 if (attr->ia_valid & ATTR_MODE)
559 return -EPERM;
560
561 error = inode_change_ok(inode, attr);
1025774c
CH		 562 if (error)
563 return error;
564
565 if ((attr->ia_valid & ATTR_SIZE) &&
566 attr->ia_size != i_size_read(inode)) {
567 error = vmtruncate(inode, attr->ia_size);
568 if (error)
569 return error;
570 }
571
572 setattr_copy(inode, attr);
573 mark_inode_dirty(inode);
574 return 0;
6d76fa58
LT		 575}
576
c5ef1c42 577static const struct inode_operations proc_def_inode_operations = {
6d76fa58
LT		 578 .setattr = proc_setattr,
579};
580
a1a2c409
MS		 581static int mounts_open_common(struct inode *inode, struct file *file,
582 const struct seq_operations *op)
1da177e4 583{
99f89551 584 struct task_struct *task = get_proc_task(inode);
cf7b708c 585 struct nsproxy *nsp;
6b3286ed 586 struct mnt_namespace *ns = NULL;
a1a2c409 587 struct path root;
5addc5dd
AV		 588 struct proc_mounts *p;
589 int ret = -EINVAL;
1da177e4 590
99f89551 591 if (task) {
cf7b708c
PE		 592 rcu_read_lock();
593 nsp = task_nsproxy(task);
594 if (nsp) {
595 ns = nsp->mnt_ns;
863c4702
AD		 596 if (ns)
597 get_mnt_ns(ns);
598 }
cf7b708c 599 rcu_read_unlock();
f7ad3c6b 600 if (ns && get_task_root(task, &root) == 0)
7c2c7d99 601 ret = 0;
99f89551
EB		 602 put_task_struct(task);
603 }
5addc5dd 604
a1a2c409
MS		 605 if (!ns)
606 goto err;
7c2c7d99 607 if (ret)
a1a2c409
MS		 608 goto err_put_ns;
609
a1a2c409
MS		 610 ret = -ENOMEM;
611 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
612 if (!p)
613 goto err_put_path;
614
615 file->private_data = &p->m;
616 ret = seq_open(file, op);
617 if (ret)
618 goto err_free;
619
620 p->m.private = p;
621 p->ns = ns;
622 p->root = root;
623 p->event = ns->event;
624
625 return 0;
626
627 err_free:
628 kfree(p);
629 err_put_path:
630 path_put(&root);
631 err_put_ns:
632 put_mnt_ns(ns);
633 err:
1da177e4
LT		 634 return ret;
635}
636
637static int mounts_release(struct inode *inode, struct file *file)
638{
a1a2c409
MS		 639 struct proc_mounts *p = file->private_data;
640 path_put(&p->root);
641 put_mnt_ns(p->ns);
1da177e4
LT		 642 return seq_release(inode, file);
643}
644
5addc5dd
AV		 645static unsigned mounts_poll(struct file *file, poll_table *wait)
646{
647 struct proc_mounts *p = file->private_data;
31b07093 648 unsigned res = POLLIN | POLLRDNORM;
5addc5dd 649
9f5596af
AV		 650 poll_wait(file, &p->ns->poll, wait);
651 if (mnt_had_events(p))
31b07093 652 res |= POLLERR | POLLPRI;
5addc5dd
AV		 653
654 return res;
655}
656
a1a2c409
MS		 657static int mounts_open(struct inode *inode, struct file *file)
658{
659 return mounts_open_common(inode, file, &mounts_op);
660}
661
00977a59 662static const struct file_operations proc_mounts_operations = {
1da177e4
LT		 663 .open = mounts_open,
664 .read = seq_read,
665 .llseek = seq_lseek,
666 .release = mounts_release,
5addc5dd 667 .poll = mounts_poll,
1da177e4
LT		 668};
669
2d4d4864
RP		 670static int mountinfo_open(struct inode *inode, struct file *file)
671{
672 return mounts_open_common(inode, file, &mountinfo_op);
673}
674
675static const struct file_operations proc_mountinfo_operations = {
676 .open = mountinfo_open,
677 .read = seq_read,
678 .llseek = seq_lseek,
679 .release = mounts_release,
680 .poll = mounts_poll,
681};
682
b4629fe2
CL		 683static int mountstats_open(struct inode *inode, struct file *file)
684{
a1a2c409 685 return mounts_open_common(inode, file, &mountstats_op);
b4629fe2
CL		 686}
687
00977a59 688static const struct file_operations proc_mountstats_operations = {
b4629fe2
CL		 689 .open = mountstats_open,
690 .read = seq_read,
691 .llseek = seq_lseek,
692 .release = mounts_release,
693};
694
1da177e4
LT		 695#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
696
697static ssize_t proc_info_read(struct file * file, char __user * buf,
698 size_t count, loff_t *ppos)
699{
2fddfeef 700 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 701 unsigned long page;
702 ssize_t length;
99f89551
EB		 703 struct task_struct *task = get_proc_task(inode);
704
705 length = -ESRCH;
706 if (!task)
707 goto out_no_task;
1da177e4
LT		 708
709 if (count > PROC_BLOCK_SIZE)
710 count = PROC_BLOCK_SIZE;
99f89551
EB		 711
712 length = -ENOMEM;
e12ba74d 713 if (!(page = __get_free_page(GFP_TEMPORARY)))
99f89551 714 goto out;
1da177e4
LT		 715
716 length = PROC_I(inode)->op.proc_read(task, (char*)page);
717
718 if (length >= 0)
719 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
720 free_page(page);
99f89551
EB		 721out:
722 put_task_struct(task);
723out_no_task:
1da177e4
LT		 724 return length;
725}
726
00977a59 727static const struct file_operations proc_info_file_operations = {
1da177e4 728 .read = proc_info_read,
87df8424 729 .llseek = generic_file_llseek,
1da177e4
LT		 730};
731
be614086
EB		 732static int proc_single_show(struct seq_file *m, void *v)
733{
734 struct inode *inode = m->private;
735 struct pid_namespace *ns;
736 struct pid *pid;
737 struct task_struct *task;
738 int ret;
739
740 ns = inode->i_sb->s_fs_info;
741 pid = proc_pid(inode);
742 task = get_pid_task(pid, PIDTYPE_PID);
743 if (!task)
744 return -ESRCH;
745
746 ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
747
748 put_task_struct(task);
749 return ret;
750}
751
752static int proc_single_open(struct inode *inode, struct file *filp)
753{
754 int ret;
755 ret = single_open(filp, proc_single_show, NULL);
756 if (!ret) {
757 struct seq_file *m = filp->private_data;
758
759 m->private = inode;
760 }
761 return ret;
762}
763
764static const struct file_operations proc_single_file_operations = {
765 .open = proc_single_open,
766 .read = seq_read,
767 .llseek = seq_lseek,
768 .release = single_release,
769};
770
1da177e4
LT		 771static int mem_open(struct inode* inode, struct file* file)
772{
773 file->private_data = (void*)((long)current->self_exec_id);
774 return 0;
775}
776
777static ssize_t mem_read(struct file * file, char __user * buf,
778 size_t count, loff_t *ppos)
779{
2fddfeef 780 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1da177e4
LT		 781 char *page;
782 unsigned long src = *ppos;
783 int ret = -ESRCH;
784 struct mm_struct *mm;
785
99f89551
EB		 786 if (!task)
787 goto out_no_task;
788
638fa202 789 if (check_mem_permission(task))
1da177e4
LT		 790 goto out;
791
792 ret = -ENOMEM;
e12ba74d 793 page = (char *)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 794 if (!page)
795 goto out;
796
797 ret = 0;
798
799 mm = get_task_mm(task);
800 if (!mm)
801 goto out_free;
802
803 ret = -EIO;
804
805 if (file->private_data != (void*)((long)current->self_exec_id))
806 goto out_put;
807
808 ret = 0;
809
810 while (count > 0) {
811 int this_len, retval;
812
813 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
814 retval = access_process_vm(task, src, page, this_len, 0);
638fa202 815 if (!retval || check_mem_permission(task)) {
1da177e4
LT		 816 if (!ret)
817 ret = -EIO;
818 break;
819 }
820
821 if (copy_to_user(buf, page, retval)) {
822 ret = -EFAULT;
823 break;
824 }
825
826 ret += retval;
827 src += retval;
828 buf += retval;
829 count -= retval;
830 }
831 *ppos = src;
832
833out_put:
834 mmput(mm);
835out_free:
836 free_page((unsigned long) page);
837out:
99f89551
EB		 838 put_task_struct(task);
839out_no_task:
1da177e4
LT		 840 return ret;
841}
842
843#define mem_write NULL
844
845#ifndef mem_write
846/* This is a security hazard */
63967fa9 847static ssize_t mem_write(struct file * file, const char __user *buf,
1da177e4
LT		 848 size_t count, loff_t *ppos)
849{
f7ca54f4 850 int copied;
1da177e4 851 char *page;
2fddfeef 852 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1da177e4
LT		 853 unsigned long dst = *ppos;
854
99f89551
EB		 855 copied = -ESRCH;
856 if (!task)
857 goto out_no_task;
858
638fa202 859 if (check_mem_permission(task))
99f89551 860 goto out;
1da177e4 861
99f89551 862 copied = -ENOMEM;
e12ba74d 863 page = (char *)__get_free_page(GFP_TEMPORARY);
1da177e4 864 if (!page)
99f89551 865 goto out;
1da177e4 866
f7ca54f4 867 copied = 0;
1da177e4
LT		 868 while (count > 0) {
869 int this_len, retval;
870
871 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
872 if (copy_from_user(page, buf, this_len)) {
873 copied = -EFAULT;
874 break;
875 }
876 retval = access_process_vm(task, dst, page, this_len, 1);
877 if (!retval) {
878 if (!copied)
879 copied = -EIO;
880 break;
881 }
882 copied += retval;
883 buf += retval;
884 dst += retval;
885 count -= retval;
886 }
887 *ppos = dst;
888 free_page((unsigned long) page);
99f89551
EB		 889out:
890 put_task_struct(task);
891out_no_task:
1da177e4
LT		 892 return copied;
893}
894#endif
895
85863e47 896loff_t mem_lseek(struct file *file, loff_t offset, int orig)
1da177e4
LT		 897{
898 switch (orig) {
899 case 0:
900 file->f_pos = offset;
901 break;
902 case 1:
903 file->f_pos += offset;
904 break;
905 default:
906 return -EINVAL;
907 }
908 force_successful_syscall_return();
909 return file->f_pos;
910}
911
00977a59 912static const struct file_operations proc_mem_operations = {
1da177e4
LT		 913 .llseek = mem_lseek,
914 .read = mem_read,
915 .write = mem_write,
916 .open = mem_open,
917};
918
315e28c8
JP		 919static ssize_t environ_read(struct file *file, char __user *buf,
920 size_t count, loff_t *ppos)
921{
922 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
923 char *page;
924 unsigned long src = *ppos;
925 int ret = -ESRCH;
926 struct mm_struct *mm;
927
928 if (!task)
929 goto out_no_task;
930
006ebb40 931 if (!ptrace_may_access(task, PTRACE_MODE_READ))
315e28c8
JP		 932 goto out;
933
934 ret = -ENOMEM;
935 page = (char *)__get_free_page(GFP_TEMPORARY);
936 if (!page)
937 goto out;
938
939 ret = 0;
940
941 mm = get_task_mm(task);
942 if (!mm)
943 goto out_free;
944
945 while (count > 0) {
946 int this_len, retval, max_len;
947
948 this_len = mm->env_end - (mm->env_start + src);
949
950 if (this_len <= 0)
951 break;
952
953 max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
954 this_len = (this_len > max_len) ? max_len : this_len;
955
956 retval = access_process_vm(task, (mm->env_start + src),
957 page, this_len, 0);
958
959 if (retval <= 0) {
960 ret = retval;
961 break;
962 }
963
964 if (copy_to_user(buf, page, retval)) {
965 ret = -EFAULT;
966 break;
967 }
968
969 ret += retval;
970 src += retval;
971 buf += retval;
972 count -= retval;
973 }
974 *ppos = src;
975
976 mmput(mm);
977out_free:
978 free_page((unsigned long) page);
979out:
980 put_task_struct(task);
981out_no_task:
982 return ret;
983}
984
985static const struct file_operations proc_environ_operations = {
986 .read = environ_read,
87df8424 987 .llseek = generic_file_llseek,
315e28c8
JP		 988};
989
1da177e4
LT		 990static ssize_t oom_adjust_read(struct file *file, char __user *buf,
991 size_t count, loff_t *ppos)
992{
2fddfeef 993 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
8578cea7 994 char buffer[PROC_NUMBUF];
1da177e4 995 size_t len;
28b83c51
KM		 996 int oom_adjust = OOM_DISABLE;
997 unsigned long flags;
1da177e4 998
99f89551
EB		 999 if (!task)
1000 return -ESRCH;
28b83c51
KM		 1001
1002 if (lock_task_sighand(task, &flags)) {
1003 oom_adjust = task->signal->oom_adj;
1004 unlock_task_sighand(task, &flags);
1005 }
1006
99f89551
EB		 1007 put_task_struct(task);
1008
8578cea7 1009 len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
0c28f287
AM		 1010
1011 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1da177e4
LT		 1012}
1013
1014static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
1015 size_t count, loff_t *ppos)
1016{
99f89551 1017 struct task_struct *task;
5d863b89
KM		 1018 char buffer[PROC_NUMBUF];
1019 long oom_adjust;
28b83c51 1020 unsigned long flags;
5d863b89 1021 int err;
1da177e4 1022
8578cea7
EB		 1023 memset(buffer, 0, sizeof(buffer));
1024 if (count > sizeof(buffer) - 1)
1025 count = sizeof(buffer) - 1;
1da177e4
LT		 1026 if (copy_from_user(buffer, buf, count))
1027 return -EFAULT;
5d863b89
KM		 1028
1029 err = strict_strtol(strstrip(buffer), 0, &oom_adjust);
1030 if (err)
1031 return -EINVAL;
8ac773b4
AD		 1032 if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
1033 oom_adjust != OOM_DISABLE)
1da177e4 1034 return -EINVAL;
5d863b89 1035
2fddfeef 1036 task = get_proc_task(file->f_path.dentry->d_inode);
99f89551
EB		 1037 if (!task)
1038 return -ESRCH;
28b83c51
KM		 1039 if (!lock_task_sighand(task, &flags)) {
1040 put_task_struct(task);
1041 return -ESRCH;
1042 }
1043
1044 if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
1045 unlock_task_sighand(task, &flags);
8fb4fc68
GJ		 1046 put_task_struct(task);
1047 return -EACCES;
1048 }
28b83c51 1049
51b1bd2a
DR		 1050 /*
1051 * Warn that /proc/pid/oom_adj is deprecated, see
1052 * Documentation/feature-removal-schedule.txt.
1053 */
1054 printk_once(KERN_WARNING "%s (%d): /proc/%d/oom_adj is deprecated, "
1055 "please use /proc/%d/oom_score_adj instead.\n",
1056 current->comm, task_pid_nr(current),
1057 task_pid_nr(task), task_pid_nr(task));
28b83c51 1058 task->signal->oom_adj = oom_adjust;
a63d83f4
DR		 1059 /*
1060 * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum
1061 * value is always attainable.
1062 */
1063 if (task->signal->oom_adj == OOM_ADJUST_MAX)
1064 task->signal->oom_score_adj = OOM_SCORE_ADJ_MAX;
1065 else
1066 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
1067 -OOM_DISABLE;
28b83c51 1068 unlock_task_sighand(task, &flags);
99f89551 1069 put_task_struct(task);
5d863b89
KM		 1070
1071 return count;
1da177e4
LT		 1072}
1073
00977a59 1074static const struct file_operations proc_oom_adjust_operations = {
1da177e4
LT		 1075 .read = oom_adjust_read,
1076 .write = oom_adjust_write,
87df8424 1077 .llseek = generic_file_llseek,
1da177e4
LT		 1078};
1079
a63d83f4
DR		 1080static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
1081 size_t count, loff_t *ppos)
1082{
1083 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
1084 char buffer[PROC_NUMBUF];
1085 int oom_score_adj = OOM_SCORE_ADJ_MIN;
1086 unsigned long flags;
1087 size_t len;
1088
1089 if (!task)
1090 return -ESRCH;
1091 if (lock_task_sighand(task, &flags)) {
1092 oom_score_adj = task->signal->oom_score_adj;
1093 unlock_task_sighand(task, &flags);
1094 }
1095 put_task_struct(task);
1096 len = snprintf(buffer, sizeof(buffer), "%d\n", oom_score_adj);
1097 return simple_read_from_buffer(buf, count, ppos, buffer, len);
1098}
1099
1100static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
1101 size_t count, loff_t *ppos)
1102{
1103 struct task_struct *task;
1104 char buffer[PROC_NUMBUF];
1105 unsigned long flags;
1106 long oom_score_adj;
1107 int err;
1108
1109 memset(buffer, 0, sizeof(buffer));
1110 if (count > sizeof(buffer) - 1)
1111 count = sizeof(buffer) - 1;
1112 if (copy_from_user(buffer, buf, count))
1113 return -EFAULT;
1114
1115 err = strict_strtol(strstrip(buffer), 0, &oom_score_adj);
1116 if (err)
1117 return -EINVAL;
1118 if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
1119 oom_score_adj > OOM_SCORE_ADJ_MAX)
1120 return -EINVAL;
1121
1122 task = get_proc_task(file->f_path.dentry->d_inode);
1123 if (!task)
1124 return -ESRCH;
1125 if (!lock_task_sighand(task, &flags)) {
1126 put_task_struct(task);
1127 return -ESRCH;
1128 }
1129 if (oom_score_adj < task->signal->oom_score_adj &&
1130 !capable(CAP_SYS_RESOURCE)) {
1131 unlock_task_sighand(task, &flags);
1132 put_task_struct(task);
1133 return -EACCES;
1134 }
1135
1136 task->signal->oom_score_adj = oom_score_adj;
1137 /*
1138 * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
1139 * always attainable.
1140 */
1141 if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
1142 task->signal->oom_adj = OOM_DISABLE;
1143 else
1144 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
1145 OOM_SCORE_ADJ_MAX;
1146 unlock_task_sighand(task, &flags);
1147 put_task_struct(task);
1148 return count;
1149}
1150
1151static const struct file_operations proc_oom_score_adj_operations = {
1152 .read = oom_score_adj_read,
1153 .write = oom_score_adj_write,
1154};
1155
1da177e4
LT		 1156#ifdef CONFIG_AUDITSYSCALL
1157#define TMPBUFLEN 21
1158static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
1159 size_t count, loff_t *ppos)
1160{
2fddfeef 1161 struct inode * inode = file->f_path.dentry->d_inode;
99f89551 1162 struct task_struct *task = get_proc_task(inode);
1da177e4
LT		 1163 ssize_t length;
1164 char tmpbuf[TMPBUFLEN];
1165
99f89551
EB		 1166 if (!task)
1167 return -ESRCH;
1da177e4 1168 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
0c11b942 1169 audit_get_loginuid(task));
99f89551 1170 put_task_struct(task);
1da177e4
LT		 1171 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1172}
1173
1174static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1175 size_t count, loff_t *ppos)
1176{
2fddfeef 1177 struct inode * inode = file->f_path.dentry->d_inode;
1da177e4
LT		 1178 char *page, *tmp;
1179 ssize_t length;
1da177e4
LT		 1180 uid_t loginuid;
1181
1182 if (!capable(CAP_AUDIT_CONTROL))
1183 return -EPERM;
1184
7dc52157
PM		 1185 rcu_read_lock();
1186 if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) {
1187 rcu_read_unlock();
1da177e4 1188 return -EPERM;
7dc52157
PM		 1189 }
1190 rcu_read_unlock();
1da177e4 1191
e0182909
AV		 1192 if (count >= PAGE_SIZE)
1193 count = PAGE_SIZE - 1;
1da177e4
LT		 1194
1195 if (*ppos != 0) {
1196 /* No partial writes. */
1197 return -EINVAL;
1198 }
e12ba74d 1199 page = (char*)__get_free_page(GFP_TEMPORARY);
1da177e4
LT		 1200 if (!page)
1201 return -ENOMEM;
1202 length = -EFAULT;
1203 if (copy_from_user(page, buf, count))
1204 goto out_free_page;
1205
e0182909 1206 page[count] = '\0';
1da177e4
LT		 1207 loginuid = simple_strtoul(page, &tmp, 10);
1208 if (tmp == page) {
1209 length = -EINVAL;
1210 goto out_free_page;
1211
1212 }
99f89551 1213 length = audit_set_loginuid(current, loginuid);
1da177e4
LT		 1214 if (likely(length == 0))
1215 length = count;
1216
1217out_free_page:
1218 free_page((unsigned long) page);
1219 return length;
1220}
1221
00977a59 1222static const struct file_operations proc_loginuid_operations = {
1da177e4
LT		 1223 .read = proc_loginuid_read,
1224 .write = proc_loginuid_write,
87df8424 1225 .llseek = generic_file_llseek,
1da177e4 1226};
1e0bd755
EP		 1227
1228static ssize_t proc_sessionid_read(struct file * file, char __user * buf,
1229 size_t count, loff_t *ppos)
1230{
1231 struct inode * inode = file->f_path.dentry->d_inode;
1232 struct task_struct *task = get_proc_task(inode);
1233 ssize_t length;
1234 char tmpbuf[TMPBUFLEN];
1235
1236 if (!task)
1237 return -ESRCH;
1238 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1239 audit_get_sessionid(task));
1240 put_task_struct(task);
1241 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1242}
1243
1244static const struct file_operations proc_sessionid_operations = {
1245 .read = proc_sessionid_read,
87df8424 1246 .llseek = generic_file_llseek,
1e0bd755 1247};
1da177e4
LT		 1248#endif
1249
f4f154fd
AM		 1250#ifdef CONFIG_FAULT_INJECTION
1251static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
1252 size_t count, loff_t *ppos)
1253{
1254 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
1255 char buffer[PROC_NUMBUF];
1256 size_t len;
1257 int make_it_fail;
f4f154fd
AM		 1258
1259 if (!task)
1260 return -ESRCH;
1261 make_it_fail = task->make_it_fail;
1262 put_task_struct(task);
1263
1264 len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
0c28f287
AM		 1265
1266 return simple_read_from_buffer(buf, count, ppos, buffer, len);
f4f154fd
AM		 1267}
1268
1269static ssize_t proc_fault_inject_write(struct file * file,
1270 const char __user * buf, size_t count, loff_t *ppos)
1271{
1272 struct task_struct *task;
1273 char buffer[PROC_NUMBUF], *end;
1274 int make_it_fail;
1275
1276 if (!capable(CAP_SYS_RESOURCE))
1277 return -EPERM;
1278 memset(buffer, 0, sizeof(buffer));
1279 if (count > sizeof(buffer) - 1)
1280 count = sizeof(buffer) - 1;
1281 if (copy_from_user(buffer, buf, count))
1282 return -EFAULT;
cba8aafe
VL		 1283 make_it_fail = simple_strtol(strstrip(buffer), &end, 0);
1284 if (*end)
1285 return -EINVAL;
f4f154fd
AM		 1286 task = get_proc_task(file->f_dentry->d_inode);
1287 if (!task)
1288 return -ESRCH;
1289 task->make_it_fail = make_it_fail;
1290 put_task_struct(task);
cba8aafe
VL		 1291
1292 return count;
f4f154fd
AM		 1293}
1294
00977a59 1295static const struct file_operations proc_fault_inject_operations = {
f4f154fd
AM		 1296 .read = proc_fault_inject_read,
1297 .write = proc_fault_inject_write,
87df8424 1298 .llseek = generic_file_llseek,
f4f154fd
AM		 1299};
1300#endif
1301
9745512c 1302
43ae34cb
IM		 1303#ifdef CONFIG_SCHED_DEBUG
1304/*
1305 * Print out various scheduling related per-task fields:
1306 */
1307static int sched_show(struct seq_file *m, void *v)
1308{
1309 struct inode *inode = m->private;
1310 struct task_struct *p;
1311
43ae34cb
IM		 1312 p = get_proc_task(inode);
1313 if (!p)
1314 return -ESRCH;
1315 proc_sched_show_task(p, m);
1316
1317 put_task_struct(p);
1318
1319 return 0;
1320}
1321
1322static ssize_t
1323sched_write(struct file *file, const char __user *buf,
1324 size_t count, loff_t *offset)
1325{
1326 struct inode *inode = file->f_path.dentry->d_inode;
1327 struct task_struct *p;
1328
43ae34cb
IM		 1329 p = get_proc_task(inode);
1330 if (!p)
1331 return -ESRCH;
1332 proc_sched_set_task(p);
1333
1334 put_task_struct(p);
1335
1336 return count;
1337}
1338
1339static int sched_open(struct inode *inode, struct file *filp)
1340{
1341 int ret;
1342
1343 ret = single_open(filp, sched_show, NULL);
1344 if (!ret) {
1345 struct seq_file *m = filp->private_data;
1346
1347 m->private = inode;
1348 }
1349 return ret;
1350}
1351
1352static const struct file_operations proc_pid_sched_operations = {
1353 .open = sched_open,
1354 .read = seq_read,
1355 .write = sched_write,
1356 .llseek = seq_lseek,
5ea473a1 1357 .release = single_release,
43ae34cb
IM		 1358};
1359
1360#endif
1361
4614a696
JS		 1362static ssize_t comm_write(struct file *file, const char __user *buf,
1363 size_t count, loff_t *offset)
1364{
1365 struct inode *inode = file->f_path.dentry->d_inode;
1366 struct task_struct *p;
1367 char buffer[TASK_COMM_LEN];
1368
1369 memset(buffer, 0, sizeof(buffer));
1370 if (count > sizeof(buffer) - 1)
1371 count = sizeof(buffer) - 1;
1372 if (copy_from_user(buffer, buf, count))
1373 return -EFAULT;
1374
1375 p = get_proc_task(inode);
1376 if (!p)
1377 return -ESRCH;
1378
1379 if (same_thread_group(current, p))
1380 set_task_comm(p, buffer);
1381 else
1382 count = -EINVAL;
1383
1384 put_task_struct(p);
1385
1386 return count;
1387}
1388
1389static int comm_show(struct seq_file *m, void *v)
1390{
1391 struct inode *inode = m->private;
1392 struct task_struct *p;
1393
1394 p = get_proc_task(inode);
1395 if (!p)
1396 return -ESRCH;
1397
1398 task_lock(p);
1399 seq_printf(m, "%s\n", p->comm);
1400 task_unlock(p);
1401
1402 put_task_struct(p);
1403
1404 return 0;
1405}
1406
1407static int comm_open(struct inode *inode, struct file *filp)
1408{
1409 int ret;
1410
1411 ret = single_open(filp, comm_show, NULL);
1412 if (!ret) {
1413 struct seq_file *m = filp->private_data;
1414
1415 m->private = inode;
1416 }
1417 return ret;
1418}
1419
1420static const struct file_operations proc_pid_set_comm_operations = {
1421 .open = comm_open,
1422 .read = seq_read,
1423 .write = comm_write,
1424 .llseek = seq_lseek,
1425 .release = single_release,
1426};
1427
925d1c40
MH		 1428/*
1429 * We added or removed a vma mapping the executable. The vmas are only mapped
1430 * during exec and are not mapped with the mmap system call.
1431 * Callers must hold down_write() on the mm's mmap_sem for these
1432 */
1433void added_exe_file_vma(struct mm_struct *mm)
1434{
1435 mm->num_exe_file_vmas++;
1436}
1437
1438void removed_exe_file_vma(struct mm_struct *mm)
1439{
1440 mm->num_exe_file_vmas--;
1441 if ((mm->num_exe_file_vmas == 0) && mm->exe_file){
1442 fput(mm->exe_file);
1443 mm->exe_file = NULL;
1444 }
1445
1446}
1447
1448void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file)
1449{
1450 if (new_exe_file)
1451 get_file(new_exe_file);
1452 if (mm->exe_file)
1453 fput(mm->exe_file);
1454 mm->exe_file = new_exe_file;
1455 mm->num_exe_file_vmas = 0;
1456}
1457
1458struct file *get_mm_exe_file(struct mm_struct *mm)
1459{
1460 struct file *exe_file;
1461
1462 /* We need mmap_sem to protect against races with removal of
1463 * VM_EXECUTABLE vmas */
1464 down_read(&mm->mmap_sem);
1465 exe_file = mm->exe_file;
1466 if (exe_file)
1467 get_file(exe_file);
1468 up_read(&mm->mmap_sem);
1469 return exe_file;
1470}
1471
1472void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm)
1473{
1474 /* It's safe to write the exe_file pointer without exe_file_lock because
1475 * this is called during fork when the task is not yet in /proc */
1476 newmm->exe_file = get_mm_exe_file(oldmm);
1477}
1478
1479static int proc_exe_link(struct inode *inode, struct path *exe_path)
1480{
1481 struct task_struct *task;
1482 struct mm_struct *mm;
1483 struct file *exe_file;
1484
1485 task = get_proc_task(inode);
1486 if (!task)
1487 return -ENOENT;
1488 mm = get_task_mm(task);
1489 put_task_struct(task);
1490 if (!mm)
1491 return -ENOENT;
1492 exe_file = get_mm_exe_file(mm);
1493 mmput(mm);
1494 if (exe_file) {
1495 *exe_path = exe_file->f_path;
1496 path_get(&exe_file->f_path);
1497 fput(exe_file);
1498 return 0;
1499 } else
1500 return -ENOENT;
1501}
1502
008b150a 1503static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT		 1504{
1505 struct inode *inode = dentry->d_inode;
1506 int error = -EACCES;
1507
1508 /* We don't need a base pointer in the /proc filesystem */
1d957f9b 1509 path_put(&nd->path);
1da177e4 1510
778c1144
EB		 1511 /* Are we allowed to snoop on the tasks file descriptors? */
1512 if (!proc_fd_access_allowed(inode))
1da177e4 1513 goto out;
1da177e4 1514
3dcd25f3 1515 error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
1da177e4 1516out:
008b150a 1517 return ERR_PTR(error);
1da177e4
LT		 1518}
1519
3dcd25f3 1520static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
1da177e4 1521{
e12ba74d 1522 char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
3dcd25f3 1523 char *pathname;
1da177e4
LT		 1524 int len;
1525
1526 if (!tmp)
1527 return -ENOMEM;
0c28f287 1528
8df9d1a4 1529 pathname = d_path_with_unreachable(path, tmp, PAGE_SIZE);
3dcd25f3
JB		 1530 len = PTR_ERR(pathname);
1531 if (IS_ERR(pathname))
1da177e4 1532 goto out;
3dcd25f3 1533 len = tmp + PAGE_SIZE - 1 - pathname;
1da177e4
LT		 1534
1535 if (len > buflen)
1536 len = buflen;
3dcd25f3 1537 if (copy_to_user(buffer, pathname, len))
1da177e4
LT		 1538 len = -EFAULT;
1539 out:
1540 free_page((unsigned long)tmp);
1541 return len;
1542}
1543
1544static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1545{
1546 int error = -EACCES;
1547 struct inode *inode = dentry->d_inode;
3dcd25f3 1548 struct path path;
1da177e4 1549
778c1144
EB		 1550 /* Are we allowed to snoop on the tasks file descriptors? */
1551 if (!proc_fd_access_allowed(inode))
1da177e4 1552 goto out;
1da177e4 1553
3dcd25f3 1554 error = PROC_I(inode)->op.proc_get_link(inode, &path);
1da177e4
LT		 1555 if (error)
1556 goto out;
1557
3dcd25f3
JB		 1558 error = do_proc_readlink(&path, buffer, buflen);
1559 path_put(&path);
1da177e4 1560out:
1da177e4
LT		 1561 return error;
1562}
1563
c5ef1c42 1564static const struct inode_operations proc_pid_link_inode_operations = {
1da177e4 1565 .readlink = proc_pid_readlink,
6d76fa58
LT		 1566 .follow_link = proc_pid_follow_link,
1567 .setattr = proc_setattr,
1da177e4
LT		 1568};
1569
28a6d671
EB		 1570
1571/* building an inode */
1572
1573static int task_dumpable(struct task_struct *task)
1da177e4 1574{
28a6d671
EB		 1575 int dumpable = 0;
1576 struct mm_struct *mm;
1da177e4 1577
28a6d671
EB		 1578 task_lock(task);
1579 mm = task->mm;
1580 if (mm)
6c5d5238 1581 dumpable = get_dumpable(mm);
28a6d671
EB		 1582 task_unlock(task);
1583 if(dumpable == 1)
1584 return 1;
1585 return 0;
1586}
1da177e4 1587
1da177e4 1588
61a28784 1589static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
28a6d671
EB		 1590{
1591 struct inode * inode;
1592 struct proc_inode *ei;
c69e8d9c 1593 const struct cred *cred;
1da177e4 1594
28a6d671 1595 /* We need a new inode */
1da177e4 1596
28a6d671
EB		 1597 inode = new_inode(sb);
1598 if (!inode)
1599 goto out;
1600
1601 /* Common stuff */
1602 ei = PROC_I(inode);
1603 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
28a6d671
EB		 1604 inode->i_op = &proc_def_inode_operations;
1605
1606 /*
1607 * grab the reference to task.
1608 */
1a657f78 1609 ei->pid = get_task_pid(task, PIDTYPE_PID);
28a6d671
EB		 1610 if (!ei->pid)
1611 goto out_unlock;
1612
28a6d671 1613 if (task_dumpable(task)) {
c69e8d9c
DH		 1614 rcu_read_lock();
1615 cred = __task_cred(task);
1616 inode->i_uid = cred->euid;
1617 inode->i_gid = cred->egid;
1618 rcu_read_unlock();
1da177e4 1619 }
28a6d671
EB		 1620 security_task_to_inode(task, inode);
1621
1da177e4 1622out:
28a6d671
EB		 1623 return inode;
1624
1625out_unlock:
1626 iput(inode);
1627 return NULL;
1da177e4
LT		 1628}
1629
28a6d671 1630static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
1da177e4 1631{
1da177e4 1632 struct inode *inode = dentry->d_inode;
28a6d671 1633 struct task_struct *task;
c69e8d9c
DH		 1634 const struct cred *cred;
1635
28a6d671 1636 generic_fillattr(inode, stat);
1da177e4 1637
28a6d671
EB		 1638 rcu_read_lock();
1639 stat->uid = 0;
1640 stat->gid = 0;
1641 task = pid_task(proc_pid(inode), PIDTYPE_PID);
1642 if (task) {
1643 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1644 task_dumpable(task)) {
c69e8d9c
DH		 1645 cred = __task_cred(task);
1646 stat->uid = cred->euid;
1647 stat->gid = cred->egid;
1da177e4
LT		 1648 }
1649 }
28a6d671 1650 rcu_read_unlock();
d6e71144 1651 return 0;
1da177e4
LT		 1652}
1653
1da177e4
LT		 1654/* dentry stuff */
1655
1656/*
1657 * Exceptional case: normally we are not allowed to unhash a busy
1658 * directory. In this case, however, we can do it - no aliasing problems
1659 * due to the way we treat inodes.
1660 *
1661 * Rewrite the inode's ownerships here because the owning task may have
1662 * performed a setuid(), etc.
99f89551
EB		 1663 *
1664 * Before the /proc/pid/status file was created the only way to read
1665 * the effective uid of a /process was to stat /proc/pid. Reading
1666 * /proc/pid/status is slow enough that procps and other packages
1667 * kept stating /proc/pid. To keep the rules in /proc simple I have
1668 * made this apply to all per process world readable and executable
1669 * directories.
1da177e4
LT		 1670 */
1671static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1672{
1673 struct inode *inode = dentry->d_inode;
99f89551 1674 struct task_struct *task = get_proc_task(inode);
c69e8d9c
DH		 1675 const struct cred *cred;
1676
99f89551
EB		 1677 if (task) {
1678 if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
1679 task_dumpable(task)) {
c69e8d9c
DH		 1680 rcu_read_lock();
1681 cred = __task_cred(task);
1682 inode->i_uid = cred->euid;
1683 inode->i_gid = cred->egid;
1684 rcu_read_unlock();
1da177e4
LT		 1685 } else {
1686 inode->i_uid = 0;
1687 inode->i_gid = 0;
1688 }
9ee8ab9f 1689 inode->i_mode &= ~(S_ISUID | S_ISGID);
1da177e4 1690 security_task_to_inode(task, inode);
99f89551 1691 put_task_struct(task);
1da177e4
LT		 1692 return 1;
1693 }
1694 d_drop(dentry);
1695 return 0;
1696}
1697
28a6d671 1698static int pid_delete_dentry(struct dentry * dentry)
99f89551 1699{
28a6d671
EB		 1700 /* Is the task we represent dead?
1701 * If so, then don't put the dentry on the lru list,
1702 * kill it immediately.
1703 */
1704 return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
1705}
1706
d72f71eb 1707static const struct dentry_operations pid_dentry_operations =
28a6d671
EB		 1708{
1709 .d_revalidate = pid_revalidate,
1710 .d_delete = pid_delete_dentry,
1711};
1712
1713/* Lookups */
1714
c5141e6d
ED		 1715typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
1716 struct task_struct *, const void *);
61a28784 1717
1c0d04c9
EB		 1718/*
1719 * Fill a directory entry.
1720 *
1721 * If possible create the dcache entry and derive our inode number and
1722 * file type from dcache entry.
1723 *
1724 * Since all of the proc inode numbers are dynamically generated, the inode
1725 * numbers do not exist until the inode is cache. This means creating the
1726 * the dcache entry in readdir is necessary to keep the inode numbers
1727 * reported by readdir in sync with the inode numbers reported
1728 * by stat.
1729 */
61a28784
EB		 1730static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
1731 char *name, int len,
c5141e6d 1732 instantiate_t instantiate, struct task_struct *task, const void *ptr)
61a28784 1733{
2fddfeef 1734 struct dentry *child, *dir = filp->f_path.dentry;
61a28784
EB		 1735 struct inode *inode;
1736 struct qstr qname;
1737 ino_t ino = 0;
1738 unsigned type = DT_UNKNOWN;
1739
1740 qname.name = name;
1741 qname.len = len;
1742 qname.hash = full_name_hash(name, len);
1743
1744 child = d_lookup(dir, &qname);
1745 if (!child) {
1746 struct dentry *new;
1747 new = d_alloc(dir, &qname);
1748 if (new) {
1749 child = instantiate(dir->d_inode, new, task, ptr);
1750 if (child)
1751 dput(new);
1752 else
1753 child = new;
1754 }
1755 }
1756 if (!child || IS_ERR(child) || !child->d_inode)
1757 goto end_instantiate;
1758 inode = child->d_inode;
1759 if (inode) {
1760 ino = inode->i_ino;
1761 type = inode->i_mode >> 12;
1762 }
1763 dput(child);
1764end_instantiate:
1765 if (!ino)
1766 ino = find_inode_number(dir, &qname);
1767 if (!ino)
1768 ino = 1;
1769 return filldir(dirent, name, len, filp->f_pos, ino, type);
1770}
1771
28a6d671
EB		 1772static unsigned name_to_int(struct dentry *dentry)
1773{
1774 const char *name = dentry->d_name.name;
1775 int len = dentry->d_name.len;
1776 unsigned n = 0;
1777
1778 if (len > 1 && *name == '0')
1779 goto out;
1780 while (len-- > 0) {
1781 unsigned c = *name++ - '0';
1782 if (c > 9)
1783 goto out;
1784 if (n >= (~0U-9)/10)
1785 goto out;
1786 n *= 10;
1787 n += c;
1788 }
1789 return n;
1790out:
1791 return ~0U;
1792}
1793
27932742
MS		 1794#define PROC_FDINFO_MAX 64
1795
3dcd25f3 1796static int proc_fd_info(struct inode *inode, struct path *path, char *info)
28a6d671
EB		 1797{
1798 struct task_struct *task = get_proc_task(inode);
1799 struct files_struct *files = NULL;
1800 struct file *file;
1801 int fd = proc_fd(inode);
99f89551 1802
99f89551 1803 if (task) {
28a6d671
EB		 1804 files = get_files_struct(task);
1805 put_task_struct(task);
1806 }
1807 if (files) {
1808 /*
1809 * We are not taking a ref to the file structure, so we must
1810 * hold ->file_lock.
1811 */
1812 spin_lock(&files->file_lock);
1813 file = fcheck_files(files, fd);
1814 if (file) {
3dcd25f3
JB		 1815 if (path) {
1816 *path = file->f_path;
1817 path_get(&file->f_path);
1818 }
27932742
MS		 1819 if (info)
1820 snprintf(info, PROC_FDINFO_MAX,
1821 "pos:\t%lli\n"
1822 "flags:\t0%o\n",
1823 (long long) file->f_pos,
1824 file->f_flags);
28a6d671
EB		 1825 spin_unlock(&files->file_lock);
1826 put_files_struct(files);
1827 return 0;
99f89551 1828 }
28a6d671
EB		 1829 spin_unlock(&files->file_lock);
1830 put_files_struct(files);
99f89551 1831 }
28a6d671 1832 return -ENOENT;
99f89551
EB		 1833}
1834
3dcd25f3 1835static int proc_fd_link(struct inode *inode, struct path *path)
27932742 1836{
3dcd25f3 1837 return proc_fd_info(inode, path, NULL);
27932742
MS		 1838}
1839
1da177e4
LT		 1840static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1841{
1842 struct inode *inode = dentry->d_inode;
99f89551 1843 struct task_struct *task = get_proc_task(inode);
aed7a6c4 1844 int fd = proc_fd(inode);
1da177e4 1845 struct files_struct *files;
c69e8d9c 1846 const struct cred *cred;
1da177e4 1847
99f89551
EB		 1848 if (task) {
1849 files = get_files_struct(task);
1850 if (files) {
1851 rcu_read_lock();
1852 if (fcheck_files(files, fd)) {
1853 rcu_read_unlock();
1854 put_files_struct(files);
1855 if (task_dumpable(task)) {
c69e8d9c
DH		 1856 rcu_read_lock();
1857 cred = __task_cred(task);
1858 inode->i_uid = cred->euid;
1859 inode->i_gid = cred->egid;
1860 rcu_read_unlock();
99f89551
EB		 1861 } else {
1862 inode->i_uid = 0;
1863 inode->i_gid = 0;
1864 }
9ee8ab9f 1865 inode->i_mode &= ~(S_ISUID | S_ISGID);
99f89551
EB		 1866 security_task_to_inode(task, inode);
1867 put_task_struct(task);
1868 return 1;
1869 }
b835996f 1870 rcu_read_unlock();
1da177e4 1871 put_files_struct(files);
1da177e4 1872 }
99f89551 1873 put_task_struct(task);
1da177e4
LT		 1874 }
1875 d_drop(dentry);
1876 return 0;
1877}
1878
d72f71eb 1879static const struct dentry_operations tid_fd_dentry_operations =
1da177e4
LT		 1880{
1881 .d_revalidate = tid_fd_revalidate,
1882 .d_delete = pid_delete_dentry,
1883};
1884
444ceed8 1885static struct dentry *proc_fd_instantiate(struct inode *dir,
c5141e6d 1886 struct dentry *dentry, struct task_struct *task, const void *ptr)
1da177e4 1887{
c5141e6d 1888 unsigned fd = *(const unsigned *)ptr;
444ceed8
EB		 1889 struct file *file;
1890 struct files_struct *files;
1891 struct inode *inode;
1892 struct proc_inode *ei;
1893 struct dentry *error = ERR_PTR(-ENOENT);
1da177e4 1894
61a28784 1895 inode = proc_pid_make_inode(dir->i_sb, task);
1da177e4
LT		 1896 if (!inode)
1897 goto out;
1898 ei = PROC_I(inode);
aed7a6c4 1899 ei->fd = fd;
1da177e4
LT		 1900 files = get_files_struct(task);
1901 if (!files)
444ceed8 1902 goto out_iput;
1da177e4 1903 inode->i_mode = S_IFLNK;
ca99c1da
DS		 1904
1905 /*
1906 * We are not taking a ref to the file structure, so we must
1907 * hold ->file_lock.
1908 */
1909 spin_lock(&files->file_lock);
1da177e4
LT		 1910 file = fcheck_files(files, fd);
1911 if (!file)
444ceed8 1912 goto out_unlock;
aeb5d727 1913 if (file->f_mode & FMODE_READ)
1da177e4 1914 inode->i_mode |= S_IRUSR | S_IXUSR;
aeb5d727 1915 if (file->f_mode & FMODE_WRITE)
1da177e4 1916 inode->i_mode |= S_IWUSR | S_IXUSR;
ca99c1da 1917 spin_unlock(&files->file_lock);
1da177e4 1918 put_files_struct(files);
444ceed8 1919
1da177e4
LT		 1920 inode->i_op = &proc_pid_link_inode_operations;
1921 inode->i_size = 64;
1922 ei->op.proc_get_link = proc_fd_link;
1923 dentry->d_op = &tid_fd_dentry_operations;
1924 d_add(dentry, inode);
cd6a3ce9
EB		 1925 /* Close the race of the process dying before we return the dentry */
1926 if (tid_fd_revalidate(dentry, NULL))
444ceed8 1927 error = NULL;
1da177e4 1928
444ceed8
EB		 1929 out:
1930 return error;
1931out_unlock:
ca99c1da 1932 spin_unlock(&files->file_lock);
1da177e4 1933 put_files_struct(files);
444ceed8 1934out_iput:
1da177e4 1935 iput(inode);
cd6a3ce9 1936 goto out;
1da177e4
LT		 1937}
1938
27932742
MS		 1939static struct dentry *proc_lookupfd_common(struct inode *dir,
1940 struct dentry *dentry,
1941 instantiate_t instantiate)
444ceed8
EB		 1942{
1943 struct task_struct *task = get_proc_task(dir);
1944 unsigned fd = name_to_int(dentry);
1945 struct dentry *result = ERR_PTR(-ENOENT);
1946
1947 if (!task)
1948 goto out_no_task;
1949 if (fd == ~0U)
1950 goto out;
1951
27932742 1952 result = instantiate(dir, dentry, task, &fd);
444ceed8
EB		 1953out:
1954 put_task_struct(task);
1955out_no_task:
1956 return result;
1957}
1958
27932742
MS		 1959static int proc_readfd_common(struct file * filp, void * dirent,
1960 filldir_t filldir, instantiate_t instantiate)
28a6d671 1961{
2fddfeef 1962 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 1963 struct inode *inode = dentry->d_inode;
1964 struct task_struct *p = get_proc_task(inode);
457c2510 1965 unsigned int fd, ino;
28a6d671 1966 int retval;
28a6d671 1967 struct files_struct * files;
1da177e4 1968
28a6d671
EB		 1969 retval = -ENOENT;
1970 if (!p)
1971 goto out_no_task;
1972 retval = 0;
28a6d671
EB		 1973
1974 fd = filp->f_pos;
1975 switch (fd) {
1976 case 0:
1977 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
1978 goto out;
1979 filp->f_pos++;
1980 case 1:
1981 ino = parent_ino(dentry);
1982 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
1983 goto out;
1984 filp->f_pos++;
1985 default:
1986 files = get_files_struct(p);
1987 if (!files)
1988 goto out;
1989 rcu_read_lock();
28a6d671 1990 for (fd = filp->f_pos-2;
9b4f526c 1991 fd < files_fdtable(files)->max_fds;
28a6d671 1992 fd++, filp->f_pos++) {
27932742
MS		 1993 char name[PROC_NUMBUF];
1994 int len;
28a6d671
EB		 1995
1996 if (!fcheck_files(files, fd))
1997 continue;
1998 rcu_read_unlock();
1999
27932742
MS		 2000 len = snprintf(name, sizeof(name), "%d", fd);
2001 if (proc_fill_cache(filp, dirent, filldir,
2002 name, len, instantiate,
2003 p, &fd) < 0) {
28a6d671
EB		 2004 rcu_read_lock();
2005 break;
2006 }
2007 rcu_read_lock();
2008 }
2009 rcu_read_unlock();
2010 put_files_struct(files);
2011 }
2012out:
2013 put_task_struct(p);
2014out_no_task:
2015 return retval;
2016}
2017
27932742
MS		 2018static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
2019 struct nameidata *nd)
2020{
2021 return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
2022}
2023
2024static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
2025{
2026 return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
2027}
2028
2029static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
2030 size_t len, loff_t *ppos)
2031{
2032 char tmp[PROC_FDINFO_MAX];
3dcd25f3 2033 int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp);
27932742
MS		 2034 if (!err)
2035 err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
2036 return err;
2037}
2038
2039static const struct file_operations proc_fdinfo_file_operations = {
87df8424 2040 .open = nonseekable_open,
27932742
MS		 2041 .read = proc_fdinfo_read,
2042};
2043
00977a59 2044static const struct file_operations proc_fd_operations = {
28a6d671
EB		 2045 .read = generic_read_dir,
2046 .readdir = proc_readfd,
1da177e4
LT		 2047};
2048
8948e11f
AD		 2049/*
2050 * /proc/pid/fd needs a special permission handler so that a process can still
2051 * access /proc/self/fd after it has executed a setuid().
2052 */
e6305c43 2053static int proc_fd_permission(struct inode *inode, int mask)
8948e11f
AD		 2054{
2055 int rv;
2056
2057 rv = generic_permission(inode, mask, NULL);
2058 if (rv == 0)
2059 return 0;
2060 if (task_pid(current) == proc_pid(inode))
2061 rv = 0;
2062 return rv;
2063}
2064
1da177e4
LT		 2065/*
2066 * proc directories can do almost nothing..
2067 */
c5ef1c42 2068static const struct inode_operations proc_fd_inode_operations = {
1da177e4 2069 .lookup = proc_lookupfd,
8948e11f 2070 .permission = proc_fd_permission,
6d76fa58 2071 .setattr = proc_setattr,
1da177e4
LT		 2072};
2073
27932742
MS		 2074static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
2075 struct dentry *dentry, struct task_struct *task, const void *ptr)
2076{
2077 unsigned fd = *(unsigned *)ptr;
2078 struct inode *inode;
2079 struct proc_inode *ei;
2080 struct dentry *error = ERR_PTR(-ENOENT);
2081
2082 inode = proc_pid_make_inode(dir->i_sb, task);
2083 if (!inode)
2084 goto out;
2085 ei = PROC_I(inode);
2086 ei->fd = fd;
2087 inode->i_mode = S_IFREG | S_IRUSR;
2088 inode->i_fop = &proc_fdinfo_file_operations;
2089 dentry->d_op = &tid_fd_dentry_operations;
2090 d_add(dentry, inode);
2091 /* Close the race of the process dying before we return the dentry */
2092 if (tid_fd_revalidate(dentry, NULL))
2093 error = NULL;
2094
2095 out:
2096 return error;
2097}
2098
2099static struct dentry *proc_lookupfdinfo(struct inode *dir,
2100 struct dentry *dentry,
2101 struct nameidata *nd)
2102{
2103 return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
2104}
2105
2106static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
2107{
2108 return proc_readfd_common(filp, dirent, filldir,
2109 proc_fdinfo_instantiate);
2110}
2111
2112static const struct file_operations proc_fdinfo_operations = {
2113 .read = generic_read_dir,
2114 .readdir = proc_readfdinfo,
2115};
2116
2117/*
2118 * proc directories can do almost nothing..
2119 */
2120static const struct inode_operations proc_fdinfo_inode_operations = {
2121 .lookup = proc_lookupfdinfo,
2122 .setattr = proc_setattr,
2123};
2124
2125
444ceed8 2126static struct dentry *proc_pident_instantiate(struct inode *dir,
c5141e6d 2127 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8 2128{
c5141e6d 2129 const struct pid_entry *p = ptr;
444ceed8
EB		 2130 struct inode *inode;
2131 struct proc_inode *ei;
bd6daba9 2132 struct dentry *error = ERR_PTR(-ENOENT);
444ceed8 2133
61a28784 2134 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2135 if (!inode)
2136 goto out;
2137
2138 ei = PROC_I(inode);
2139 inode->i_mode = p->mode;
2140 if (S_ISDIR(inode->i_mode))
2141 inode->i_nlink = 2; /* Use getattr to fix if necessary */
2142 if (p->iop)
2143 inode->i_op = p->iop;
2144 if (p->fop)
2145 inode->i_fop = p->fop;
2146 ei->op = p->op;
2147 dentry->d_op = &pid_dentry_operations;
2148 d_add(dentry, inode);
2149 /* Close the race of the process dying before we return the dentry */
2150 if (pid_revalidate(dentry, NULL))
2151 error = NULL;
2152out:
2153 return error;
2154}
2155
1da177e4
LT		 2156static struct dentry *proc_pident_lookup(struct inode *dir,
2157 struct dentry *dentry,
c5141e6d 2158 const struct pid_entry *ents,
7bcd6b0e 2159 unsigned int nents)
1da177e4 2160{
cd6a3ce9 2161 struct dentry *error;
99f89551 2162 struct task_struct *task = get_proc_task(dir);
c5141e6d 2163 const struct pid_entry *p, *last;
1da177e4 2164
cd6a3ce9 2165 error = ERR_PTR(-ENOENT);
1da177e4 2166
99f89551
EB		 2167 if (!task)
2168 goto out_no_task;
1da177e4 2169
20cdc894
EB		 2170 /*
2171 * Yes, it does not scale. And it should not. Don't add
2172 * new entries into /proc/<tgid>/ without very good reasons.
2173 */
7bcd6b0e
EB		 2174 last = &ents[nents - 1];
2175 for (p = ents; p <= last; p++) {
1da177e4
LT		 2176 if (p->len != dentry->d_name.len)
2177 continue;
2178 if (!memcmp(dentry->d_name.name, p->name, p->len))
2179 break;
2180 }
7bcd6b0e 2181 if (p > last)
1da177e4
LT		 2182 goto out;
2183
444ceed8 2184 error = proc_pident_instantiate(dir, dentry, task, p);
1da177e4 2185out:
99f89551
EB		 2186 put_task_struct(task);
2187out_no_task:
cd6a3ce9 2188 return error;
1da177e4
LT		 2189}
2190
c5141e6d
ED		 2191static int proc_pident_fill_cache(struct file *filp, void *dirent,
2192 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2193{
2194 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2195 proc_pident_instantiate, task, p);
2196}
2197
28a6d671
EB		 2198static int proc_pident_readdir(struct file *filp,
2199 void *dirent, filldir_t filldir,
c5141e6d 2200 const struct pid_entry *ents, unsigned int nents)
28a6d671
EB		 2201{
2202 int i;
2fddfeef 2203 struct dentry *dentry = filp->f_path.dentry;
28a6d671
EB		 2204 struct inode *inode = dentry->d_inode;
2205 struct task_struct *task = get_proc_task(inode);
c5141e6d 2206 const struct pid_entry *p, *last;
28a6d671
EB		 2207 ino_t ino;
2208 int ret;
2209
2210 ret = -ENOENT;
2211 if (!task)
61a28784 2212 goto out_no_task;
28a6d671
EB		 2213
2214 ret = 0;
28a6d671
EB		 2215 i = filp->f_pos;
2216 switch (i) {
2217 case 0:
2218 ino = inode->i_ino;
2219 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
2220 goto out;
2221 i++;
2222 filp->f_pos++;
2223 /* fall through */
2224 case 1:
2225 ino = parent_ino(dentry);
2226 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
2227 goto out;
2228 i++;
2229 filp->f_pos++;
2230 /* fall through */
2231 default:
2232 i -= 2;
2233 if (i >= nents) {
2234 ret = 1;
2235 goto out;
2236 }
2237 p = ents + i;
7bcd6b0e
EB		 2238 last = &ents[nents - 1];
2239 while (p <= last) {
61a28784 2240 if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
28a6d671
EB		 2241 goto out;
2242 filp->f_pos++;
2243 p++;
2244 }
2245 }
2246
2247 ret = 1;
2248out:
61a28784
EB		 2249 put_task_struct(task);
2250out_no_task:
28a6d671 2251 return ret;
1da177e4
LT		 2252}
2253
28a6d671
EB		 2254#ifdef CONFIG_SECURITY
2255static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
2256 size_t count, loff_t *ppos)
2257{
2fddfeef 2258 struct inode * inode = file->f_path.dentry->d_inode;
04ff9708 2259 char *p = NULL;
28a6d671
EB		 2260 ssize_t length;
2261 struct task_struct *task = get_proc_task(inode);
2262
28a6d671 2263 if (!task)
04ff9708 2264 return -ESRCH;
28a6d671
EB		 2265
2266 length = security_getprocattr(task,
2fddfeef 2267 (char*)file->f_path.dentry->d_name.name,
04ff9708 2268 &p);
28a6d671 2269 put_task_struct(task);
04ff9708
AV		 2270 if (length > 0)
2271 length = simple_read_from_buffer(buf, count, ppos, p, length);
2272 kfree(p);
28a6d671 2273 return length;
1da177e4
LT		 2274}
2275
28a6d671
EB		 2276static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
2277 size_t count, loff_t *ppos)
2278{
2fddfeef 2279 struct inode * inode = file->f_path.dentry->d_inode;
28a6d671
EB		 2280 char *page;
2281 ssize_t length;
2282 struct task_struct *task = get_proc_task(inode);
2283
2284 length = -ESRCH;
2285 if (!task)
2286 goto out_no_task;
2287 if (count > PAGE_SIZE)
2288 count = PAGE_SIZE;
2289
2290 /* No partial writes. */
2291 length = -EINVAL;
2292 if (*ppos != 0)
2293 goto out;
2294
2295 length = -ENOMEM;
e12ba74d 2296 page = (char*)__get_free_page(GFP_TEMPORARY);
28a6d671
EB		 2297 if (!page)
2298 goto out;
2299
2300 length = -EFAULT;
2301 if (copy_from_user(page, buf, count))
2302 goto out_free;
2303
107db7c7
DH		 2304 /* Guard against adverse ptrace interaction */
2305 length = mutex_lock_interruptible(&task->cred_guard_mutex);
2306 if (length < 0)
2307 goto out_free;
2308
28a6d671 2309 length = security_setprocattr(task,
2fddfeef 2310 (char*)file->f_path.dentry->d_name.name,
28a6d671 2311 (void*)page, count);
107db7c7 2312 mutex_unlock(&task->cred_guard_mutex);
28a6d671
EB		 2313out_free:
2314 free_page((unsigned long) page);
2315out:
2316 put_task_struct(task);
2317out_no_task:
2318 return length;
2319}
2320
00977a59 2321static const struct file_operations proc_pid_attr_operations = {
28a6d671
EB		 2322 .read = proc_pid_attr_read,
2323 .write = proc_pid_attr_write,
87df8424 2324 .llseek = generic_file_llseek,
28a6d671
EB		 2325};
2326
c5141e6d 2327static const struct pid_entry attr_dir_stuff[] = {
631f9c18
AD		 2328 REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2329 REG("prev", S_IRUGO, proc_pid_attr_operations),
2330 REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2331 REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2332 REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
2333 REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations),
28a6d671
EB		 2334};
2335
72d9dcfc 2336static int proc_attr_dir_readdir(struct file * filp,
28a6d671
EB		 2337 void * dirent, filldir_t filldir)
2338{
2339 return proc_pident_readdir(filp,dirent,filldir,
72d9dcfc 2340 attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2341}
2342
00977a59 2343static const struct file_operations proc_attr_dir_operations = {
1da177e4 2344 .read = generic_read_dir,
72d9dcfc 2345 .readdir = proc_attr_dir_readdir,
1da177e4
LT		 2346};
2347
72d9dcfc 2348static struct dentry *proc_attr_dir_lookup(struct inode *dir,
28a6d671
EB		 2349 struct dentry *dentry, struct nameidata *nd)
2350{
7bcd6b0e
EB		 2351 return proc_pident_lookup(dir, dentry,
2352 attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
28a6d671
EB		 2353}
2354
c5ef1c42 2355static const struct inode_operations proc_attr_dir_inode_operations = {
72d9dcfc 2356 .lookup = proc_attr_dir_lookup,
99f89551 2357 .getattr = pid_getattr,
6d76fa58 2358 .setattr = proc_setattr,
1da177e4
LT		 2359};
2360
28a6d671
EB		 2361#endif
2362
698ba7b5 2363#ifdef CONFIG_ELF_CORE
3cb4a0bb
KH		 2364static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
2365 size_t count, loff_t *ppos)
2366{
2367 struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
2368 struct mm_struct *mm;
2369 char buffer[PROC_NUMBUF];
2370 size_t len;
2371 int ret;
2372
2373 if (!task)
2374 return -ESRCH;
2375
2376 ret = 0;
2377 mm = get_task_mm(task);
2378 if (mm) {
2379 len = snprintf(buffer, sizeof(buffer), "%08lx\n",
2380 ((mm->flags & MMF_DUMP_FILTER_MASK) >>
2381 MMF_DUMP_FILTER_SHIFT));
2382 mmput(mm);
2383 ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
2384 }
2385
2386 put_task_struct(task);
2387
2388 return ret;
2389}
2390
2391static ssize_t proc_coredump_filter_write(struct file *file,
2392 const char __user *buf,
2393 size_t count,
2394 loff_t *ppos)
2395{
2396 struct task_struct *task;
2397 struct mm_struct *mm;
2398 char buffer[PROC_NUMBUF], *end;
2399 unsigned int val;
2400 int ret;
2401 int i;
2402 unsigned long mask;
2403
2404 ret = -EFAULT;
2405 memset(buffer, 0, sizeof(buffer));
2406 if (count > sizeof(buffer) - 1)
2407 count = sizeof(buffer) - 1;
2408 if (copy_from_user(buffer, buf, count))
2409 goto out_no_task;
2410
2411 ret = -EINVAL;
2412 val = (unsigned int)simple_strtoul(buffer, &end, 0);
2413 if (*end == '\n')
2414 end++;
2415 if (end - buffer == 0)
2416 goto out_no_task;
2417
2418 ret = -ESRCH;
2419 task = get_proc_task(file->f_dentry->d_inode);
2420 if (!task)
2421 goto out_no_task;
2422
2423 ret = end - buffer;
2424 mm = get_task_mm(task);
2425 if (!mm)
2426 goto out_no_mm;
2427
2428 for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
2429 if (val & mask)
2430 set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2431 else
2432 clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
2433 }
2434
2435 mmput(mm);
2436 out_no_mm:
2437 put_task_struct(task);
2438 out_no_task:
2439 return ret;
2440}
2441
2442static const struct file_operations proc_coredump_filter_operations = {
2443 .read = proc_coredump_filter_read,
2444 .write = proc_coredump_filter_write,
87df8424 2445 .llseek = generic_file_llseek,
3cb4a0bb
KH		 2446};
2447#endif
2448
28a6d671
EB		 2449/*
2450 * /proc/self:
2451 */
2452static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
2453 int buflen)
2454{
488e5bc4 2455 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2456 pid_t tgid = task_tgid_nr_ns(current, ns);
28a6d671 2457 char tmp[PROC_NUMBUF];
b55fcb22 2458 if (!tgid)
488e5bc4 2459 return -ENOENT;
b55fcb22 2460 sprintf(tmp, "%d", tgid);
28a6d671
EB		 2461 return vfs_readlink(dentry,buffer,buflen,tmp);
2462}
2463
2464static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
2465{
488e5bc4 2466 struct pid_namespace *ns = dentry->d_sb->s_fs_info;
b55fcb22 2467 pid_t tgid = task_tgid_nr_ns(current, ns);
7fee4868
AV		 2468 char *name = ERR_PTR(-ENOENT);
2469 if (tgid) {
2470 name = __getname();
2471 if (!name)
2472 name = ERR_PTR(-ENOMEM);
2473 else
2474 sprintf(name, "%d", tgid);
2475 }
2476 nd_set_link(nd, name);
2477 return NULL;
2478}
2479
2480static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
2481 void *cookie)
2482{
2483 char *s = nd_get_link(nd);
2484 if (!IS_ERR(s))
2485 __putname(s);
28a6d671
EB		 2486}
2487
c5ef1c42 2488static const struct inode_operations proc_self_inode_operations = {
28a6d671
EB		 2489 .readlink = proc_self_readlink,
2490 .follow_link = proc_self_follow_link,
7fee4868 2491 .put_link = proc_self_put_link,
28a6d671
EB		 2492};
2493
801199ce
EB		 2494/*
2495 * proc base
2496 *
2497 * These are the directory entries in the root directory of /proc
2498 * that properly belong to the /proc filesystem, as they describe
2499 * describe something that is process related.
2500 */
c5141e6d 2501static const struct pid_entry proc_base_stuff[] = {
61a28784 2502 NOD("self", S_IFLNK|S_IRWXUGO,
801199ce 2503 &proc_self_inode_operations, NULL, {}),
801199ce
EB		 2504};
2505
2506/*
2507 * Exceptional case: normally we are not allowed to unhash a busy
2508 * directory. In this case, however, we can do it - no aliasing problems
2509 * due to the way we treat inodes.
2510 */
2511static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
2512{
2513 struct inode *inode = dentry->d_inode;
2514 struct task_struct *task = get_proc_task(inode);
2515 if (task) {
2516 put_task_struct(task);
2517 return 1;
2518 }
2519 d_drop(dentry);
2520 return 0;
2521}
2522
d72f71eb 2523static const struct dentry_operations proc_base_dentry_operations =
801199ce
EB		 2524{
2525 .d_revalidate = proc_base_revalidate,
2526 .d_delete = pid_delete_dentry,
2527};
2528
444ceed8 2529static struct dentry *proc_base_instantiate(struct inode *dir,
c5141e6d 2530 struct dentry *dentry, struct task_struct *task, const void *ptr)
801199ce 2531{
c5141e6d 2532 const struct pid_entry *p = ptr;
801199ce 2533 struct inode *inode;
801199ce 2534 struct proc_inode *ei;
73d36460 2535 struct dentry *error;
801199ce
EB		 2536
2537 /* Allocate the inode */
2538 error = ERR_PTR(-ENOMEM);
2539 inode = new_inode(dir->i_sb);
2540 if (!inode)
2541 goto out;
2542
2543 /* Initialize the inode */
2544 ei = PROC_I(inode);
2545 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
801199ce
EB		 2546
2547 /*
2548 * grab the reference to the task.
2549 */
1a657f78 2550 ei->pid = get_task_pid(task, PIDTYPE_PID);
801199ce
EB		 2551 if (!ei->pid)
2552 goto out_iput;
2553
801199ce
EB		 2554 inode->i_mode = p->mode;
2555 if (S_ISDIR(inode->i_mode))
2556 inode->i_nlink = 2;
2557 if (S_ISLNK(inode->i_mode))
2558 inode->i_size = 64;
2559 if (p->iop)
2560 inode->i_op = p->iop;
2561 if (p->fop)
2562 inode->i_fop = p->fop;
2563 ei->op = p->op;
2564 dentry->d_op = &proc_base_dentry_operations;
2565 d_add(dentry, inode);
2566 error = NULL;
2567out:
801199ce
EB		 2568 return error;
2569out_iput:
2570 iput(inode);
2571 goto out;
2572}
2573
444ceed8
EB		 2574static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
2575{
2576 struct dentry *error;
2577 struct task_struct *task = get_proc_task(dir);
c5141e6d 2578 const struct pid_entry *p, *last;
444ceed8
EB		 2579
2580 error = ERR_PTR(-ENOENT);
2581
2582 if (!task)
2583 goto out_no_task;
2584
2585 /* Lookup the directory entry */
7bcd6b0e
EB		 2586 last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
2587 for (p = proc_base_stuff; p <= last; p++) {
444ceed8
EB		 2588 if (p->len != dentry->d_name.len)
2589 continue;
2590 if (!memcmp(dentry->d_name.name, p->name, p->len))
2591 break;
2592 }
7bcd6b0e 2593 if (p > last)
444ceed8
EB		 2594 goto out;
2595
2596 error = proc_base_instantiate(dir, dentry, task, p);
2597
2598out:
2599 put_task_struct(task);
2600out_no_task:
2601 return error;
2602}
2603
c5141e6d
ED		 2604static int proc_base_fill_cache(struct file *filp, void *dirent,
2605 filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
61a28784
EB		 2606{
2607 return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
2608 proc_base_instantiate, task, p);
2609}
2610
aba76fdb 2611#ifdef CONFIG_TASK_IO_ACCOUNTING
297c5d92
AR		 2612static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
2613{
940389b8 2614 struct task_io_accounting acct = task->ioac;
5995477a
AR		 2615 unsigned long flags;
2616
2617 if (whole && lock_task_sighand(task, &flags)) {
2618 struct task_struct *t = task;
2619
2620 task_io_accounting_add(&acct, &task->signal->ioac);
2621 while_each_thread(task, t)
2622 task_io_accounting_add(&acct, &t->ioac);
2623
2624 unlock_task_sighand(task, &flags);
297c5d92 2625 }
aba76fdb
AM		 2626 return sprintf(buffer,
2627 "rchar: %llu\n"
2628 "wchar: %llu\n"
2629 "syscr: %llu\n"
2630 "syscw: %llu\n"
2631 "read_bytes: %llu\n"
2632 "write_bytes: %llu\n"
2633 "cancelled_write_bytes: %llu\n",
7c44319d
AB		 2634 (unsigned long long)acct.rchar,
2635 (unsigned long long)acct.wchar,
2636 (unsigned long long)acct.syscr,
2637 (unsigned long long)acct.syscw,
2638 (unsigned long long)acct.read_bytes,
2639 (unsigned long long)acct.write_bytes,
2640 (unsigned long long)acct.cancelled_write_bytes);
297c5d92
AR		 2641}
2642
2643static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
2644{
2645 return do_io_accounting(task, buffer, 0);
aba76fdb 2646}
297c5d92
AR		 2647
2648static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
2649{
2650 return do_io_accounting(task, buffer, 1);
2651}
2652#endif /* CONFIG_TASK_IO_ACCOUNTING */
aba76fdb 2653
47830723
KC		 2654static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns,
2655 struct pid *pid, struct task_struct *task)
2656{
2657 seq_printf(m, "%08x\n", task->personality);
2658 return 0;
2659}
2660
28a6d671
EB		 2661/*
2662 * Thread groups
2663 */
00977a59 2664static const struct file_operations proc_task_operations;
c5ef1c42 2665static const struct inode_operations proc_task_inode_operations;
20cdc894 2666
c5141e6d 2667static const struct pid_entry tgid_base_stuff[] = {
631f9c18
AD		 2668 DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
2669 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
2670 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
b2211a36 2671#ifdef CONFIG_NET
631f9c18 2672 DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations),
b2211a36 2673#endif
631f9c18
AD		 2674 REG("environ", S_IRUSR, proc_environ_operations),
2675 INF("auxv", S_IRUSR, proc_pid_auxv),
2676 ONE("status", S_IRUGO, proc_pid_status),
2677 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 2678 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 2679#ifdef CONFIG_SCHED_DEBUG
631f9c18 2680 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 2681#endif
4614a696 2682 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 2683#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 2684 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 2685#endif
631f9c18
AD		 2686 INF("cmdline", S_IRUGO, proc_pid_cmdline),
2687 ONE("stat", S_IRUGO, proc_tgid_stat),
2688 ONE("statm", S_IRUGO, proc_pid_statm),
2689 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 2690#ifdef CONFIG_NUMA
631f9c18 2691 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 2692#endif
631f9c18
AD		 2693 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
2694 LNK("cwd", proc_cwd_link),
2695 LNK("root", proc_root_link),
2696 LNK("exe", proc_exe_link),
2697 REG("mounts", S_IRUGO, proc_mounts_operations),
2698 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
2699 REG("mountstats", S_IRUSR, proc_mountstats_operations),
1e883281 2700#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 2701 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
2702 REG("smaps", S_IRUGO, proc_smaps_operations),
2703 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 2704#endif
2705#ifdef CONFIG_SECURITY
631f9c18 2706 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 2707#endif
2708#ifdef CONFIG_KALLSYMS
631f9c18 2709 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 2710#endif
2ec220e2
KC		 2711#ifdef CONFIG_STACKTRACE
2712 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 2713#endif
2714#ifdef CONFIG_SCHEDSTATS
631f9c18 2715 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 2716#endif
9745512c 2717#ifdef CONFIG_LATENCYTOP
631f9c18 2718 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 2719#endif
8793d854 2720#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 2721 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 2722#endif
2723#ifdef CONFIG_CGROUPS
631f9c18 2724 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 2725#endif
631f9c18
AD		 2726 INF("oom_score", S_IRUGO, proc_oom_score),
2727 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 2728 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 2729#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 2730 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
2731 REG("sessionid", S_IRUGO, proc_sessionid_operations),
28a6d671 2732#endif
f4f154fd 2733#ifdef CONFIG_FAULT_INJECTION
631f9c18 2734 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 2735#endif
698ba7b5 2736#ifdef CONFIG_ELF_CORE
631f9c18 2737 REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
3cb4a0bb 2738#endif
aba76fdb 2739#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 2740 INF("io", S_IRUGO, proc_tgid_io_accounting),
aba76fdb 2741#endif
28a6d671 2742};
1da177e4 2743
28a6d671 2744static int proc_tgid_base_readdir(struct file * filp,
1da177e4
LT		 2745 void * dirent, filldir_t filldir)
2746{
2747 return proc_pident_readdir(filp,dirent,filldir,
28a6d671 2748 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2749}
2750
00977a59 2751static const struct file_operations proc_tgid_base_operations = {
1da177e4 2752 .read = generic_read_dir,
28a6d671 2753 .readdir = proc_tgid_base_readdir,
1da177e4
LT		 2754};
2755
28a6d671 2756static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 2757 return proc_pident_lookup(dir, dentry,
2758 tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
1da177e4
LT		 2759}
2760
c5ef1c42 2761static const struct inode_operations proc_tgid_base_inode_operations = {
28a6d671 2762 .lookup = proc_tgid_base_lookup,
99f89551 2763 .getattr = pid_getattr,
6d76fa58 2764 .setattr = proc_setattr,
1da177e4 2765};
1da177e4 2766
60347f67 2767static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
1da177e4 2768{
48e6484d 2769 struct dentry *dentry, *leader, *dir;
8578cea7 2770 char buf[PROC_NUMBUF];
48e6484d
EB		 2771 struct qstr name;
2772
2773 name.name = buf;
60347f67
PE		 2774 name.len = snprintf(buf, sizeof(buf), "%d", pid);
2775 dentry = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d 2776 if (dentry) {
29f12ca3 2777 shrink_dcache_parent(dentry);
48e6484d
EB		 2778 d_drop(dentry);
2779 dput(dentry);
2780 }
1da177e4 2781
48e6484d 2782 name.name = buf;
60347f67
PE		 2783 name.len = snprintf(buf, sizeof(buf), "%d", tgid);
2784 leader = d_hash_and_lookup(mnt->mnt_root, &name);
48e6484d
EB		 2785 if (!leader)
2786 goto out;
1da177e4 2787
48e6484d
EB		 2788 name.name = "task";
2789 name.len = strlen(name.name);
2790 dir = d_hash_and_lookup(leader, &name);
2791 if (!dir)
2792 goto out_put_leader;
2793
2794 name.name = buf;
60347f67 2795 name.len = snprintf(buf, sizeof(buf), "%d", pid);
48e6484d
EB		 2796 dentry = d_hash_and_lookup(dir, &name);
2797 if (dentry) {
2798 shrink_dcache_parent(dentry);
2799 d_drop(dentry);
2800 dput(dentry);
1da177e4 2801 }
48e6484d
EB		 2802
2803 dput(dir);
2804out_put_leader:
2805 dput(leader);
2806out:
2807 return;
1da177e4
LT		 2808}
2809
0895e91d
RD		 2810/**
2811 * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
2812 * @task: task that should be flushed.
2813 *
2814 * When flushing dentries from proc, one needs to flush them from global
60347f67 2815 * proc (proc_mnt) and from all the namespaces' procs this task was seen
0895e91d
RD		 2816 * in. This call is supposed to do all of this job.
2817 *
2818 * Looks in the dcache for
2819 * /proc/@pid
2820 * /proc/@tgid/task/@pid
2821 * if either directory is present flushes it and all of it'ts children
2822 * from the dcache.
2823 *
2824 * It is safe and reasonable to cache /proc entries for a task until
2825 * that task exits. After that they just clog up the dcache with
2826 * useless entries, possibly causing useful dcache entries to be
2827 * flushed instead. This routine is proved to flush those useless
2828 * dcache entries at process exit time.
2829 *
2830 * NOTE: This routine is just an optimization so it does not guarantee
2831 * that no dcache entries will exist at process exit time it
2832 * just makes it very unlikely that any will persist.
60347f67
PE		 2833 */
2834
2835void proc_flush_task(struct task_struct *task)
2836{
9fcc2d15 2837 int i;
9b4d1cbe 2838 struct pid *pid, *tgid;
130f77ec
PE		 2839 struct upid *upid;
2840
130f77ec 2841 pid = task_pid(task);
9b4d1cbe 2842 tgid = task_tgid(task);
130f77ec 2843
9fcc2d15 2844 for (i = 0; i <= pid->level; i++) {
130f77ec
PE		 2845 upid = &pid->numbers[i];
2846 proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
9b4d1cbe 2847 tgid->numbers[i].nr);
130f77ec 2848 }
6f4e6433
PE		 2849
2850 upid = &pid->numbers[pid->level];
2851 if (upid->nr == 1)
2852 pid_ns_release_proc(upid->ns);
60347f67
PE		 2853}
2854
9711ef99
AB		 2855static struct dentry *proc_pid_instantiate(struct inode *dir,
2856 struct dentry * dentry,
c5141e6d 2857 struct task_struct *task, const void *ptr)
444ceed8
EB		 2858{
2859 struct dentry *error = ERR_PTR(-ENOENT);
2860 struct inode *inode;
2861
61a28784 2862 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 2863 if (!inode)
2864 goto out;
2865
2866 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2867 inode->i_op = &proc_tgid_base_inode_operations;
2868 inode->i_fop = &proc_tgid_base_operations;
2869 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 2870
2871 inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff,
2872 ARRAY_SIZE(tgid_base_stuff));
444ceed8
EB		 2873
2874 dentry->d_op = &pid_dentry_operations;
2875
2876 d_add(dentry, inode);
2877 /* Close the race of the process dying before we return the dentry */
2878 if (pid_revalidate(dentry, NULL))
2879 error = NULL;
2880out:
2881 return error;
2882}
2883
1da177e4
LT		 2884struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2885{
73d36460 2886 struct dentry *result;
1da177e4 2887 struct task_struct *task;
1da177e4 2888 unsigned tgid;
b488893a 2889 struct pid_namespace *ns;
1da177e4 2890
801199ce
EB		 2891 result = proc_base_lookup(dir, dentry);
2892 if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
2893 goto out;
2894
1da177e4
LT		 2895 tgid = name_to_int(dentry);
2896 if (tgid == ~0U)
2897 goto out;
2898
b488893a 2899 ns = dentry->d_sb->s_fs_info;
de758734 2900 rcu_read_lock();
b488893a 2901 task = find_task_by_pid_ns(tgid, ns);
1da177e4
LT		 2902 if (task)
2903 get_task_struct(task);
de758734 2904 rcu_read_unlock();
1da177e4
LT		 2905 if (!task)
2906 goto out;
2907
444ceed8 2908 result = proc_pid_instantiate(dir, dentry, task, NULL);
1da177e4 2909 put_task_struct(task);
1da177e4 2910out:
cd6a3ce9 2911 return result;
1da177e4
LT		 2912}
2913
1da177e4 2914/*
0804ef4b 2915 * Find the first task with tgid >= tgid
0bc58a91 2916 *
1da177e4 2917 */
19fd4bb2
EB		 2918struct tgid_iter {
2919 unsigned int tgid;
0804ef4b 2920 struct task_struct *task;
19fd4bb2
EB		 2921};
2922static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
2923{
0804ef4b 2924 struct pid *pid;
1da177e4 2925
19fd4bb2
EB		 2926 if (iter.task)
2927 put_task_struct(iter.task);
454cc105 2928 rcu_read_lock();
0804ef4b 2929retry:
19fd4bb2
EB		 2930 iter.task = NULL;
2931 pid = find_ge_pid(iter.tgid, ns);
0804ef4b 2932 if (pid) {
19fd4bb2
EB		 2933 iter.tgid = pid_nr_ns(pid, ns);
2934 iter.task = pid_task(pid, PIDTYPE_PID);
0804ef4b
EB		 2935 /* What we to know is if the pid we have find is the
2936 * pid of a thread_group_leader. Testing for task
2937 * being a thread_group_leader is the obvious thing
2938 * todo but there is a window when it fails, due to
2939 * the pid transfer logic in de_thread.
2940 *
2941 * So we perform the straight forward test of seeing
2942 * if the pid we have found is the pid of a thread
2943 * group leader, and don't worry if the task we have
2944 * found doesn't happen to be a thread group leader.
2945 * As we don't care in the case of readdir.
2946 */
19fd4bb2
EB		 2947 if (!iter.task || !has_group_leader_pid(iter.task)) {
2948 iter.tgid += 1;
0804ef4b 2949 goto retry;
19fd4bb2
EB		 2950 }
2951 get_task_struct(iter.task);
0bc58a91 2952 }
454cc105 2953 rcu_read_unlock();
19fd4bb2 2954 return iter;
1da177e4
LT		 2955}
2956
7bcd6b0e 2957#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
0804ef4b 2958
61a28784 2959static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
19fd4bb2 2960 struct tgid_iter iter)
61a28784
EB		 2961{
2962 char name[PROC_NUMBUF];
19fd4bb2 2963 int len = snprintf(name, sizeof(name), "%d", iter.tgid);
61a28784 2964 return proc_fill_cache(filp, dirent, filldir, name, len,
19fd4bb2 2965 proc_pid_instantiate, iter.task, NULL);
61a28784
EB		 2966}
2967
1da177e4
LT		 2968/* for the /proc/ directory itself, after non-process stuff has been done */
2969int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
2970{
1da177e4 2971 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2fddfeef 2972 struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
19fd4bb2 2973 struct tgid_iter iter;
b488893a 2974 struct pid_namespace *ns;
1da177e4 2975
61a28784
EB		 2976 if (!reaper)
2977 goto out_no_task;
2978
7bcd6b0e 2979 for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
c5141e6d 2980 const struct pid_entry *p = &proc_base_stuff[nr];
61a28784 2981 if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
801199ce 2982 goto out;
1da177e4
LT		 2983 }
2984
b488893a 2985 ns = filp->f_dentry->d_sb->s_fs_info;
19fd4bb2
EB		 2986 iter.task = NULL;
2987 iter.tgid = filp->f_pos - TGID_OFFSET;
2988 for (iter = next_tgid(ns, iter);
2989 iter.task;
2990 iter.tgid += 1, iter = next_tgid(ns, iter)) {
2991 filp->f_pos = iter.tgid + TGID_OFFSET;
2992 if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
2993 put_task_struct(iter.task);
0804ef4b 2994 goto out;
1da177e4 2995 }
0bc58a91 2996 }
0804ef4b
EB		 2997 filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
2998out:
61a28784
EB		 2999 put_task_struct(reaper);
3000out_no_task:
0bc58a91
EB		 3001 return 0;
3002}
1da177e4 3003
28a6d671
EB		 3004/*
3005 * Tasks
3006 */
c5141e6d 3007static const struct pid_entry tid_base_stuff[] = {
631f9c18 3008 DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
3835541d 3009 DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
631f9c18
AD		 3010 REG("environ", S_IRUSR, proc_environ_operations),
3011 INF("auxv", S_IRUSR, proc_pid_auxv),
3012 ONE("status", S_IRUGO, proc_pid_status),
3013 ONE("personality", S_IRUSR, proc_pid_personality),
3036e7b4 3014 INF("limits", S_IRUGO, proc_pid_limits),
43ae34cb 3015#ifdef CONFIG_SCHED_DEBUG
631f9c18 3016 REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations),
ebcb6734 3017#endif
4614a696 3018 REG("comm", S_IRUGO|S_IWUSR, proc_pid_set_comm_operations),
ebcb6734 3019#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
631f9c18 3020 INF("syscall", S_IRUSR, proc_pid_syscall),
43ae34cb 3021#endif
631f9c18
AD		 3022 INF("cmdline", S_IRUGO, proc_pid_cmdline),
3023 ONE("stat", S_IRUGO, proc_tid_stat),
3024 ONE("statm", S_IRUGO, proc_pid_statm),
3025 REG("maps", S_IRUGO, proc_maps_operations),
28a6d671 3026#ifdef CONFIG_NUMA
631f9c18 3027 REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
28a6d671 3028#endif
631f9c18
AD		 3029 REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
3030 LNK("cwd", proc_cwd_link),
3031 LNK("root", proc_root_link),
3032 LNK("exe", proc_exe_link),
3033 REG("mounts", S_IRUGO, proc_mounts_operations),
3034 REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
1e883281 3035#ifdef CONFIG_PROC_PAGE_MONITOR
631f9c18
AD		 3036 REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
3037 REG("smaps", S_IRUGO, proc_smaps_operations),
3038 REG("pagemap", S_IRUSR, proc_pagemap_operations),
28a6d671
EB		 3039#endif
3040#ifdef CONFIG_SECURITY
631f9c18 3041 DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations),
28a6d671
EB		 3042#endif
3043#ifdef CONFIG_KALLSYMS
631f9c18 3044 INF("wchan", S_IRUGO, proc_pid_wchan),
28a6d671 3045#endif
2ec220e2
KC		 3046#ifdef CONFIG_STACKTRACE
3047 ONE("stack", S_IRUSR, proc_pid_stack),
28a6d671
EB		 3048#endif
3049#ifdef CONFIG_SCHEDSTATS
631f9c18 3050 INF("schedstat", S_IRUGO, proc_pid_schedstat),
28a6d671 3051#endif
9745512c 3052#ifdef CONFIG_LATENCYTOP
631f9c18 3053 REG("latency", S_IRUGO, proc_lstats_operations),
9745512c 3054#endif
8793d854 3055#ifdef CONFIG_PROC_PID_CPUSET
631f9c18 3056 REG("cpuset", S_IRUGO, proc_cpuset_operations),
a424316c
PM		 3057#endif
3058#ifdef CONFIG_CGROUPS
631f9c18 3059 REG("cgroup", S_IRUGO, proc_cgroup_operations),
28a6d671 3060#endif
631f9c18
AD		 3061 INF("oom_score", S_IRUGO, proc_oom_score),
3062 REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations),
a63d83f4 3063 REG("oom_score_adj", S_IRUGO|S_IWUSR, proc_oom_score_adj_operations),
28a6d671 3064#ifdef CONFIG_AUDITSYSCALL
631f9c18
AD		 3065 REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
3066 REG("sessionid", S_IRUSR, proc_sessionid_operations),
28a6d671 3067#endif
f4f154fd 3068#ifdef CONFIG_FAULT_INJECTION
631f9c18 3069 REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
f4f154fd 3070#endif
297c5d92 3071#ifdef CONFIG_TASK_IO_ACCOUNTING
631f9c18 3072 INF("io", S_IRUGO, proc_tid_io_accounting),
297c5d92 3073#endif
28a6d671
EB		 3074};
3075
3076static int proc_tid_base_readdir(struct file * filp,
3077 void * dirent, filldir_t filldir)
3078{
3079 return proc_pident_readdir(filp,dirent,filldir,
3080 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
3081}
3082
3083static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
7bcd6b0e
EB		 3084 return proc_pident_lookup(dir, dentry,
3085 tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
28a6d671
EB		 3086}
3087
00977a59 3088static const struct file_operations proc_tid_base_operations = {
28a6d671
EB		 3089 .read = generic_read_dir,
3090 .readdir = proc_tid_base_readdir,
3091};
3092
c5ef1c42 3093static const struct inode_operations proc_tid_base_inode_operations = {
28a6d671
EB		 3094 .lookup = proc_tid_base_lookup,
3095 .getattr = pid_getattr,
3096 .setattr = proc_setattr,
3097};
3098
444ceed8 3099static struct dentry *proc_task_instantiate(struct inode *dir,
c5141e6d 3100 struct dentry *dentry, struct task_struct *task, const void *ptr)
444ceed8
EB		 3101{
3102 struct dentry *error = ERR_PTR(-ENOENT);
3103 struct inode *inode;
61a28784 3104 inode = proc_pid_make_inode(dir->i_sb, task);
444ceed8
EB		 3105
3106 if (!inode)
3107 goto out;
3108 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
3109 inode->i_op = &proc_tid_base_inode_operations;
3110 inode->i_fop = &proc_tid_base_operations;
3111 inode->i_flags|=S_IMMUTABLE;
aed54175
VN		 3112
3113 inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff,
3114 ARRAY_SIZE(tid_base_stuff));
444ceed8
EB		 3115
3116 dentry->d_op = &pid_dentry_operations;
3117
3118 d_add(dentry, inode);
3119 /* Close the race of the process dying before we return the dentry */
3120 if (pid_revalidate(dentry, NULL))
3121 error = NULL;
3122out:
3123 return error;
3124}
3125
28a6d671
EB		 3126static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
3127{
3128 struct dentry *result = ERR_PTR(-ENOENT);
3129 struct task_struct *task;
3130 struct task_struct *leader = get_proc_task(dir);
28a6d671 3131 unsigned tid;
b488893a 3132 struct pid_namespace *ns;
28a6d671
EB		 3133
3134 if (!leader)
3135 goto out_no_task;
3136
3137 tid = name_to_int(dentry);
3138 if (tid == ~0U)
3139 goto out;
3140
b488893a 3141 ns = dentry->d_sb->s_fs_info;
28a6d671 3142 rcu_read_lock();
b488893a 3143 task = find_task_by_pid_ns(tid, ns);
28a6d671
EB		 3144 if (task)
3145 get_task_struct(task);
3146 rcu_read_unlock();
3147 if (!task)
3148 goto out;
bac0abd6 3149 if (!same_thread_group(leader, task))
28a6d671
EB		 3150 goto out_drop_task;
3151
444ceed8 3152 result = proc_task_instantiate(dir, dentry, task, NULL);
28a6d671
EB		 3153out_drop_task:
3154 put_task_struct(task);
3155out:
3156 put_task_struct(leader);
3157out_no_task:
3158 return result;
3159}
3160
0bc58a91
EB		 3161/*
3162 * Find the first tid of a thread group to return to user space.
3163 *
3164 * Usually this is just the thread group leader, but if the users
3165 * buffer was too small or there was a seek into the middle of the
3166 * directory we have more work todo.
3167 *
3168 * In the case of a short read we start with find_task_by_pid.
3169 *
3170 * In the case of a seek we start with the leader and walk nr
3171 * threads past it.
3172 */
cc288738 3173static struct task_struct *first_tid(struct task_struct *leader,
b488893a 3174 int tid, int nr, struct pid_namespace *ns)
0bc58a91 3175{
a872ff0c 3176 struct task_struct *pos;
1da177e4 3177
cc288738 3178 rcu_read_lock();
0bc58a91
EB		 3179 /* Attempt to start with the pid of a thread */
3180 if (tid && (nr > 0)) {
b488893a 3181 pos = find_task_by_pid_ns(tid, ns);
a872ff0c
ON		 3182 if (pos && (pos->group_leader == leader))
3183 goto found;
0bc58a91 3184 }
1da177e4 3185
0bc58a91 3186 /* If nr exceeds the number of threads there is nothing todo */
a872ff0c
ON		 3187 pos = NULL;
3188 if (nr && nr >= get_nr_threads(leader))
3189 goto out;
1da177e4 3190
a872ff0c
ON		 3191 /* If we haven't found our starting place yet start
3192 * with the leader and walk nr threads forward.
0bc58a91 3193 */
a872ff0c
ON		 3194 for (pos = leader; nr > 0; --nr) {
3195 pos = next_thread(pos);
3196 if (pos == leader) {
3197 pos = NULL;
3198 goto out;
3199 }
1da177e4 3200 }
a872ff0c
ON		 3201found:
3202 get_task_struct(pos);
3203out:
cc288738 3204 rcu_read_unlock();
0bc58a91
EB		 3205 return pos;
3206}
3207
3208/*
3209 * Find the next thread in the thread list.
3210 * Return NULL if there is an error or no next thread.
3211 *
3212 * The reference to the input task_struct is released.
3213 */
3214static struct task_struct *next_tid(struct task_struct *start)
3215{
c1df7fb8 3216 struct task_struct *pos = NULL;
cc288738 3217 rcu_read_lock();
c1df7fb8 3218 if (pid_alive(start)) {
0bc58a91 3219 pos = next_thread(start);
c1df7fb8
ON		 3220 if (thread_group_leader(pos))
3221 pos = NULL;
3222 else
3223 get_task_struct(pos);
3224 }
cc288738 3225 rcu_read_unlock();
0bc58a91
EB		 3226 put_task_struct(start);
3227 return pos;
1da177e4
LT		 3228}
3229
61a28784
EB		 3230static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
3231 struct task_struct *task, int tid)
3232{
3233 char name[PROC_NUMBUF];
3234 int len = snprintf(name, sizeof(name), "%d", tid);
3235 return proc_fill_cache(filp, dirent, filldir, name, len,
3236 proc_task_instantiate, task, NULL);
3237}
3238
1da177e4
LT		 3239/* for the /proc/TGID/task/ directories */
3240static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
3241{
2fddfeef 3242 struct dentry *dentry = filp->f_path.dentry;
1da177e4 3243 struct inode *inode = dentry->d_inode;
7d895244 3244 struct task_struct *leader = NULL;
0bc58a91 3245 struct task_struct *task;
1da177e4
LT		 3246 int retval = -ENOENT;
3247 ino_t ino;
0bc58a91 3248 int tid;
b488893a 3249 struct pid_namespace *ns;
1da177e4 3250
7d895244
GC		 3251 task = get_proc_task(inode);
3252 if (!task)
3253 goto out_no_task;
3254 rcu_read_lock();
3255 if (pid_alive(task)) {
3256 leader = task->group_leader;
3257 get_task_struct(leader);
3258 }
3259 rcu_read_unlock();
3260 put_task_struct(task);
99f89551
EB		 3261 if (!leader)
3262 goto out_no_task;
1da177e4
LT		 3263 retval = 0;
3264
ee568b25 3265 switch ((unsigned long)filp->f_pos) {
1da177e4
LT		 3266 case 0:
3267 ino = inode->i_ino;
ee6f779b 3268 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3269 goto out;
ee6f779b 3270 filp->f_pos++;
1da177e4
LT		 3271 /* fall through */
3272 case 1:
3273 ino = parent_ino(dentry);
ee6f779b 3274 if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0)
1da177e4 3275 goto out;
ee6f779b 3276 filp->f_pos++;
1da177e4
LT		 3277 /* fall through */
3278 }
3279
0bc58a91
EB		 3280 /* f_version caches the tgid value that the last readdir call couldn't
3281 * return. lseek aka telldir automagically resets f_version to 0.
3282 */
b488893a 3283 ns = filp->f_dentry->d_sb->s_fs_info;
2b47c361 3284 tid = (int)filp->f_version;
0bc58a91 3285 filp->f_version = 0;
ee6f779b 3286 for (task = first_tid(leader, tid, filp->f_pos - 2, ns);
0bc58a91 3287 task;
ee6f779b 3288 task = next_tid(task), filp->f_pos++) {
b488893a 3289 tid = task_pid_nr_ns(task, ns);
61a28784 3290 if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
0bc58a91
EB		 3291 /* returning this tgid failed, save it as the first
3292 * pid for the next readir call */
2b47c361 3293 filp->f_version = (u64)tid;
0bc58a91 3294 put_task_struct(task);
1da177e4 3295 break;
0bc58a91 3296 }
1da177e4
LT		 3297 }
3298out:
99f89551
EB		 3299 put_task_struct(leader);
3300out_no_task:
1da177e4
LT		 3301 return retval;
3302}
6e66b52b
EB		 3303
3304static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
3305{
3306 struct inode *inode = dentry->d_inode;
99f89551 3307 struct task_struct *p = get_proc_task(inode);
6e66b52b
EB		 3308 generic_fillattr(inode, stat);
3309
99f89551 3310 if (p) {
99f89551 3311 stat->nlink += get_nr_threads(p);
99f89551 3312 put_task_struct(p);
6e66b52b
EB		 3313 }
3314
3315 return 0;
3316}
28a6d671 3317
c5ef1c42 3318static const struct inode_operations proc_task_inode_operations = {
28a6d671
EB		 3319 .lookup = proc_task_lookup,
3320 .getattr = proc_task_getattr,
3321 .setattr = proc_setattr,
3322};
3323
00977a59 3324static const struct file_operations proc_task_operations = {
28a6d671
EB		 3325 .read = generic_read_dir,
3326 .readdir = proc_task_readdir,
3327};
Clone of davem's net-next-2.6 tree