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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/fcntl.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
7 | #include <linux/syscalls.h> | |
8 | #include <linux/init.h> | |
9 | #include <linux/mm.h> | |
10 | #include <linux/fs.h> | |
11 | #include <linux/file.h> | |
16f7e0fe | 12 | #include <linux/capability.h> |
1da177e4 LT |
13 | #include <linux/dnotify.h> |
14 | #include <linux/smp_lock.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/security.h> | |
18 | #include <linux/ptrace.h> | |
7ed20e1a | 19 | #include <linux/signal.h> |
ab2af1f5 | 20 | #include <linux/rcupdate.h> |
1da177e4 LT |
21 | |
22 | #include <asm/poll.h> | |
23 | #include <asm/siginfo.h> | |
24 | #include <asm/uaccess.h> | |
25 | ||
26 | void fastcall set_close_on_exec(unsigned int fd, int flag) | |
27 | { | |
28 | struct files_struct *files = current->files; | |
badf1662 | 29 | struct fdtable *fdt; |
1da177e4 | 30 | spin_lock(&files->file_lock); |
badf1662 | 31 | fdt = files_fdtable(files); |
1da177e4 | 32 | if (flag) |
badf1662 | 33 | FD_SET(fd, fdt->close_on_exec); |
1da177e4 | 34 | else |
badf1662 | 35 | FD_CLR(fd, fdt->close_on_exec); |
1da177e4 LT |
36 | spin_unlock(&files->file_lock); |
37 | } | |
38 | ||
858119e1 | 39 | static int get_close_on_exec(unsigned int fd) |
1da177e4 LT |
40 | { |
41 | struct files_struct *files = current->files; | |
badf1662 | 42 | struct fdtable *fdt; |
1da177e4 | 43 | int res; |
b835996f | 44 | rcu_read_lock(); |
badf1662 DS |
45 | fdt = files_fdtable(files); |
46 | res = FD_ISSET(fd, fdt->close_on_exec); | |
b835996f | 47 | rcu_read_unlock(); |
1da177e4 LT |
48 | return res; |
49 | } | |
50 | ||
51 | /* | |
52 | * locate_fd finds a free file descriptor in the open_fds fdset, | |
53 | * expanding the fd arrays if necessary. Must be called with the | |
54 | * file_lock held for write. | |
55 | */ | |
56 | ||
57 | static int locate_fd(struct files_struct *files, | |
58 | struct file *file, unsigned int orig_start) | |
59 | { | |
60 | unsigned int newfd; | |
61 | unsigned int start; | |
62 | int error; | |
badf1662 | 63 | struct fdtable *fdt; |
1da177e4 LT |
64 | |
65 | error = -EINVAL; | |
66 | if (orig_start >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | |
67 | goto out; | |
68 | ||
69 | repeat: | |
ab2af1f5 | 70 | fdt = files_fdtable(files); |
1da177e4 LT |
71 | /* |
72 | * Someone might have closed fd's in the range | |
badf1662 | 73 | * orig_start..fdt->next_fd |
1da177e4 LT |
74 | */ |
75 | start = orig_start; | |
0c9e63fd ED |
76 | if (start < files->next_fd) |
77 | start = files->next_fd; | |
1da177e4 LT |
78 | |
79 | newfd = start; | |
badf1662 DS |
80 | if (start < fdt->max_fdset) { |
81 | newfd = find_next_zero_bit(fdt->open_fds->fds_bits, | |
82 | fdt->max_fdset, start); | |
1da177e4 LT |
83 | } |
84 | ||
85 | error = -EMFILE; | |
86 | if (newfd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | |
87 | goto out; | |
88 | ||
89 | error = expand_files(files, newfd); | |
90 | if (error < 0) | |
91 | goto out; | |
92 | ||
93 | /* | |
94 | * If we needed to expand the fs array we | |
95 | * might have blocked - try again. | |
96 | */ | |
97 | if (error) | |
98 | goto repeat; | |
99 | ||
ab2af1f5 DS |
100 | /* |
101 | * We reacquired files_lock, so we are safe as long as | |
102 | * we reacquire the fdtable pointer and use it while holding | |
103 | * the lock, no one can free it during that time. | |
104 | */ | |
0c9e63fd ED |
105 | if (start <= files->next_fd) |
106 | files->next_fd = newfd + 1; | |
ab2af1f5 | 107 | |
1da177e4 LT |
108 | error = newfd; |
109 | ||
110 | out: | |
111 | return error; | |
112 | } | |
113 | ||
114 | static int dupfd(struct file *file, unsigned int start) | |
115 | { | |
116 | struct files_struct * files = current->files; | |
badf1662 | 117 | struct fdtable *fdt; |
1da177e4 LT |
118 | int fd; |
119 | ||
120 | spin_lock(&files->file_lock); | |
121 | fd = locate_fd(files, file, start); | |
122 | if (fd >= 0) { | |
badf1662 DS |
123 | /* locate_fd() may have expanded fdtable, load the ptr */ |
124 | fdt = files_fdtable(files); | |
125 | FD_SET(fd, fdt->open_fds); | |
126 | FD_CLR(fd, fdt->close_on_exec); | |
1da177e4 LT |
127 | spin_unlock(&files->file_lock); |
128 | fd_install(fd, file); | |
129 | } else { | |
130 | spin_unlock(&files->file_lock); | |
131 | fput(file); | |
132 | } | |
133 | ||
134 | return fd; | |
135 | } | |
136 | ||
137 | asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd) | |
138 | { | |
139 | int err = -EBADF; | |
140 | struct file * file, *tofree; | |
141 | struct files_struct * files = current->files; | |
badf1662 | 142 | struct fdtable *fdt; |
1da177e4 LT |
143 | |
144 | spin_lock(&files->file_lock); | |
145 | if (!(file = fcheck(oldfd))) | |
146 | goto out_unlock; | |
147 | err = newfd; | |
148 | if (newfd == oldfd) | |
149 | goto out_unlock; | |
150 | err = -EBADF; | |
151 | if (newfd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | |
152 | goto out_unlock; | |
153 | get_file(file); /* We are now finished with oldfd */ | |
154 | ||
155 | err = expand_files(files, newfd); | |
156 | if (err < 0) | |
157 | goto out_fput; | |
158 | ||
159 | /* To avoid races with open() and dup(), we will mark the fd as | |
160 | * in-use in the open-file bitmap throughout the entire dup2() | |
161 | * process. This is quite safe: do_close() uses the fd array | |
162 | * entry, not the bitmap, to decide what work needs to be | |
163 | * done. --sct */ | |
164 | /* Doesn't work. open() might be there first. --AV */ | |
165 | ||
166 | /* Yes. It's a race. In user space. Nothing sane to do */ | |
167 | err = -EBUSY; | |
badf1662 DS |
168 | fdt = files_fdtable(files); |
169 | tofree = fdt->fd[newfd]; | |
170 | if (!tofree && FD_ISSET(newfd, fdt->open_fds)) | |
1da177e4 LT |
171 | goto out_fput; |
172 | ||
ab2af1f5 | 173 | rcu_assign_pointer(fdt->fd[newfd], file); |
badf1662 DS |
174 | FD_SET(newfd, fdt->open_fds); |
175 | FD_CLR(newfd, fdt->close_on_exec); | |
1da177e4 LT |
176 | spin_unlock(&files->file_lock); |
177 | ||
178 | if (tofree) | |
179 | filp_close(tofree, files); | |
180 | err = newfd; | |
181 | out: | |
182 | return err; | |
183 | out_unlock: | |
184 | spin_unlock(&files->file_lock); | |
185 | goto out; | |
186 | ||
187 | out_fput: | |
188 | spin_unlock(&files->file_lock); | |
189 | fput(file); | |
190 | goto out; | |
191 | } | |
192 | ||
193 | asmlinkage long sys_dup(unsigned int fildes) | |
194 | { | |
195 | int ret = -EBADF; | |
196 | struct file * file = fget(fildes); | |
197 | ||
198 | if (file) | |
199 | ret = dupfd(file, 0); | |
200 | return ret; | |
201 | } | |
202 | ||
203 | #define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | FASYNC | O_DIRECT | O_NOATIME) | |
204 | ||
205 | static int setfl(int fd, struct file * filp, unsigned long arg) | |
206 | { | |
207 | struct inode * inode = filp->f_dentry->d_inode; | |
208 | int error = 0; | |
209 | ||
7d95c8f2 | 210 | /* |
211 | * O_APPEND cannot be cleared if the file is marked as append-only | |
212 | * and the file is open for write. | |
213 | */ | |
214 | if (((arg ^ filp->f_flags) & O_APPEND) && IS_APPEND(inode)) | |
1da177e4 LT |
215 | return -EPERM; |
216 | ||
217 | /* O_NOATIME can only be set by the owner or superuser */ | |
218 | if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME)) | |
219 | if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER)) | |
220 | return -EPERM; | |
221 | ||
222 | /* required for strict SunOS emulation */ | |
223 | if (O_NONBLOCK != O_NDELAY) | |
224 | if (arg & O_NDELAY) | |
225 | arg |= O_NONBLOCK; | |
226 | ||
227 | if (arg & O_DIRECT) { | |
228 | if (!filp->f_mapping || !filp->f_mapping->a_ops || | |
229 | !filp->f_mapping->a_ops->direct_IO) | |
230 | return -EINVAL; | |
231 | } | |
232 | ||
233 | if (filp->f_op && filp->f_op->check_flags) | |
234 | error = filp->f_op->check_flags(arg); | |
235 | if (error) | |
236 | return error; | |
237 | ||
238 | lock_kernel(); | |
239 | if ((arg ^ filp->f_flags) & FASYNC) { | |
240 | if (filp->f_op && filp->f_op->fasync) { | |
241 | error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0); | |
242 | if (error < 0) | |
243 | goto out; | |
244 | } | |
245 | } | |
246 | ||
247 | filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK); | |
248 | out: | |
249 | unlock_kernel(); | |
250 | return error; | |
251 | } | |
252 | ||
253 | static void f_modown(struct file *filp, unsigned long pid, | |
254 | uid_t uid, uid_t euid, int force) | |
255 | { | |
256 | write_lock_irq(&filp->f_owner.lock); | |
257 | if (force || !filp->f_owner.pid) { | |
258 | filp->f_owner.pid = pid; | |
259 | filp->f_owner.uid = uid; | |
260 | filp->f_owner.euid = euid; | |
261 | } | |
262 | write_unlock_irq(&filp->f_owner.lock); | |
263 | } | |
264 | ||
265 | int f_setown(struct file *filp, unsigned long arg, int force) | |
266 | { | |
267 | int err; | |
268 | ||
269 | err = security_file_set_fowner(filp); | |
270 | if (err) | |
271 | return err; | |
272 | ||
273 | f_modown(filp, arg, current->uid, current->euid, force); | |
274 | return 0; | |
275 | } | |
276 | ||
277 | EXPORT_SYMBOL(f_setown); | |
278 | ||
279 | void f_delown(struct file *filp) | |
280 | { | |
281 | f_modown(filp, 0, 0, 0, 1); | |
282 | } | |
283 | ||
284 | static long do_fcntl(int fd, unsigned int cmd, unsigned long arg, | |
285 | struct file *filp) | |
286 | { | |
287 | long err = -EINVAL; | |
288 | ||
289 | switch (cmd) { | |
290 | case F_DUPFD: | |
291 | get_file(filp); | |
292 | err = dupfd(filp, arg); | |
293 | break; | |
294 | case F_GETFD: | |
295 | err = get_close_on_exec(fd) ? FD_CLOEXEC : 0; | |
296 | break; | |
297 | case F_SETFD: | |
298 | err = 0; | |
299 | set_close_on_exec(fd, arg & FD_CLOEXEC); | |
300 | break; | |
301 | case F_GETFL: | |
302 | err = filp->f_flags; | |
303 | break; | |
304 | case F_SETFL: | |
305 | err = setfl(fd, filp, arg); | |
306 | break; | |
307 | case F_GETLK: | |
308 | err = fcntl_getlk(filp, (struct flock __user *) arg); | |
309 | break; | |
310 | case F_SETLK: | |
311 | case F_SETLKW: | |
c293621b | 312 | err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg); |
1da177e4 LT |
313 | break; |
314 | case F_GETOWN: | |
315 | /* | |
316 | * XXX If f_owner is a process group, the | |
317 | * negative return value will get converted | |
318 | * into an error. Oops. If we keep the | |
319 | * current syscall conventions, the only way | |
320 | * to fix this will be in libc. | |
321 | */ | |
322 | err = filp->f_owner.pid; | |
323 | force_successful_syscall_return(); | |
324 | break; | |
325 | case F_SETOWN: | |
326 | err = f_setown(filp, arg, 1); | |
327 | break; | |
328 | case F_GETSIG: | |
329 | err = filp->f_owner.signum; | |
330 | break; | |
331 | case F_SETSIG: | |
332 | /* arg == 0 restores default behaviour. */ | |
7ed20e1a | 333 | if (!valid_signal(arg)) { |
1da177e4 LT |
334 | break; |
335 | } | |
336 | err = 0; | |
337 | filp->f_owner.signum = arg; | |
338 | break; | |
339 | case F_GETLEASE: | |
340 | err = fcntl_getlease(filp); | |
341 | break; | |
342 | case F_SETLEASE: | |
343 | err = fcntl_setlease(fd, filp, arg); | |
344 | break; | |
345 | case F_NOTIFY: | |
346 | err = fcntl_dirnotify(fd, filp, arg); | |
347 | break; | |
348 | default: | |
349 | break; | |
350 | } | |
351 | return err; | |
352 | } | |
353 | ||
354 | asmlinkage long sys_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg) | |
355 | { | |
356 | struct file *filp; | |
357 | long err = -EBADF; | |
358 | ||
359 | filp = fget(fd); | |
360 | if (!filp) | |
361 | goto out; | |
362 | ||
363 | err = security_file_fcntl(filp, cmd, arg); | |
364 | if (err) { | |
365 | fput(filp); | |
366 | return err; | |
367 | } | |
368 | ||
369 | err = do_fcntl(fd, cmd, arg, filp); | |
370 | ||
371 | fput(filp); | |
372 | out: | |
373 | return err; | |
374 | } | |
375 | ||
376 | #if BITS_PER_LONG == 32 | |
377 | asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg) | |
378 | { | |
379 | struct file * filp; | |
380 | long err; | |
381 | ||
382 | err = -EBADF; | |
383 | filp = fget(fd); | |
384 | if (!filp) | |
385 | goto out; | |
386 | ||
387 | err = security_file_fcntl(filp, cmd, arg); | |
388 | if (err) { | |
389 | fput(filp); | |
390 | return err; | |
391 | } | |
392 | err = -EBADF; | |
393 | ||
394 | switch (cmd) { | |
395 | case F_GETLK64: | |
396 | err = fcntl_getlk64(filp, (struct flock64 __user *) arg); | |
397 | break; | |
398 | case F_SETLK64: | |
399 | case F_SETLKW64: | |
c293621b PS |
400 | err = fcntl_setlk64(fd, filp, cmd, |
401 | (struct flock64 __user *) arg); | |
1da177e4 LT |
402 | break; |
403 | default: | |
404 | err = do_fcntl(fd, cmd, arg, filp); | |
405 | break; | |
406 | } | |
407 | fput(filp); | |
408 | out: | |
409 | return err; | |
410 | } | |
411 | #endif | |
412 | ||
413 | /* Table to convert sigio signal codes into poll band bitmaps */ | |
414 | ||
415 | static long band_table[NSIGPOLL] = { | |
416 | POLLIN | POLLRDNORM, /* POLL_IN */ | |
417 | POLLOUT | POLLWRNORM | POLLWRBAND, /* POLL_OUT */ | |
418 | POLLIN | POLLRDNORM | POLLMSG, /* POLL_MSG */ | |
419 | POLLERR, /* POLL_ERR */ | |
420 | POLLPRI | POLLRDBAND, /* POLL_PRI */ | |
421 | POLLHUP | POLLERR /* POLL_HUP */ | |
422 | }; | |
423 | ||
424 | static inline int sigio_perm(struct task_struct *p, | |
425 | struct fown_struct *fown, int sig) | |
426 | { | |
427 | return (((fown->euid == 0) || | |
428 | (fown->euid == p->suid) || (fown->euid == p->uid) || | |
429 | (fown->uid == p->suid) || (fown->uid == p->uid)) && | |
430 | !security_file_send_sigiotask(p, fown, sig)); | |
431 | } | |
432 | ||
433 | static void send_sigio_to_task(struct task_struct *p, | |
434 | struct fown_struct *fown, | |
435 | int fd, | |
436 | int reason) | |
437 | { | |
438 | if (!sigio_perm(p, fown, fown->signum)) | |
439 | return; | |
440 | ||
441 | switch (fown->signum) { | |
442 | siginfo_t si; | |
443 | default: | |
444 | /* Queue a rt signal with the appropriate fd as its | |
445 | value. We use SI_SIGIO as the source, not | |
446 | SI_KERNEL, since kernel signals always get | |
447 | delivered even if we can't queue. Failure to | |
448 | queue in this case _should_ be reported; we fall | |
449 | back to SIGIO in that case. --sct */ | |
450 | si.si_signo = fown->signum; | |
451 | si.si_errno = 0; | |
452 | si.si_code = reason; | |
453 | /* Make sure we are called with one of the POLL_* | |
454 | reasons, otherwise we could leak kernel stack into | |
455 | userspace. */ | |
456 | if ((reason & __SI_MASK) != __SI_POLL) | |
457 | BUG(); | |
458 | if (reason - POLL_IN >= NSIGPOLL) | |
459 | si.si_band = ~0L; | |
460 | else | |
461 | si.si_band = band_table[reason - POLL_IN]; | |
462 | si.si_fd = fd; | |
850d6fbe | 463 | if (!group_send_sig_info(fown->signum, &si, p)) |
1da177e4 LT |
464 | break; |
465 | /* fall-through: fall back on the old plain SIGIO signal */ | |
466 | case 0: | |
850d6fbe | 467 | group_send_sig_info(SIGIO, SEND_SIG_PRIV, p); |
1da177e4 LT |
468 | } |
469 | } | |
470 | ||
471 | void send_sigio(struct fown_struct *fown, int fd, int band) | |
472 | { | |
473 | struct task_struct *p; | |
474 | int pid; | |
475 | ||
476 | read_lock(&fown->lock); | |
477 | pid = fown->pid; | |
478 | if (!pid) | |
479 | goto out_unlock_fown; | |
480 | ||
481 | read_lock(&tasklist_lock); | |
482 | if (pid > 0) { | |
483 | p = find_task_by_pid(pid); | |
484 | if (p) { | |
485 | send_sigio_to_task(p, fown, fd, band); | |
486 | } | |
487 | } else { | |
488 | do_each_task_pid(-pid, PIDTYPE_PGID, p) { | |
489 | send_sigio_to_task(p, fown, fd, band); | |
490 | } while_each_task_pid(-pid, PIDTYPE_PGID, p); | |
491 | } | |
492 | read_unlock(&tasklist_lock); | |
493 | out_unlock_fown: | |
494 | read_unlock(&fown->lock); | |
495 | } | |
496 | ||
497 | static void send_sigurg_to_task(struct task_struct *p, | |
498 | struct fown_struct *fown) | |
499 | { | |
500 | if (sigio_perm(p, fown, SIGURG)) | |
850d6fbe | 501 | group_send_sig_info(SIGURG, SEND_SIG_PRIV, p); |
1da177e4 LT |
502 | } |
503 | ||
504 | int send_sigurg(struct fown_struct *fown) | |
505 | { | |
506 | struct task_struct *p; | |
507 | int pid, ret = 0; | |
508 | ||
509 | read_lock(&fown->lock); | |
510 | pid = fown->pid; | |
511 | if (!pid) | |
512 | goto out_unlock_fown; | |
513 | ||
514 | ret = 1; | |
515 | ||
516 | read_lock(&tasklist_lock); | |
517 | if (pid > 0) { | |
518 | p = find_task_by_pid(pid); | |
519 | if (p) { | |
520 | send_sigurg_to_task(p, fown); | |
521 | } | |
522 | } else { | |
523 | do_each_task_pid(-pid, PIDTYPE_PGID, p) { | |
524 | send_sigurg_to_task(p, fown); | |
525 | } while_each_task_pid(-pid, PIDTYPE_PGID, p); | |
526 | } | |
527 | read_unlock(&tasklist_lock); | |
528 | out_unlock_fown: | |
529 | read_unlock(&fown->lock); | |
530 | return ret; | |
531 | } | |
532 | ||
533 | static DEFINE_RWLOCK(fasync_lock); | |
534 | static kmem_cache_t *fasync_cache; | |
535 | ||
536 | /* | |
537 | * fasync_helper() is used by some character device drivers (mainly mice) | |
538 | * to set up the fasync queue. It returns negative on error, 0 if it did | |
539 | * no changes and positive if it added/deleted the entry. | |
540 | */ | |
541 | int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp) | |
542 | { | |
543 | struct fasync_struct *fa, **fp; | |
544 | struct fasync_struct *new = NULL; | |
545 | int result = 0; | |
546 | ||
547 | if (on) { | |
548 | new = kmem_cache_alloc(fasync_cache, SLAB_KERNEL); | |
549 | if (!new) | |
550 | return -ENOMEM; | |
551 | } | |
552 | write_lock_irq(&fasync_lock); | |
553 | for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) { | |
554 | if (fa->fa_file == filp) { | |
555 | if(on) { | |
556 | fa->fa_fd = fd; | |
557 | kmem_cache_free(fasync_cache, new); | |
558 | } else { | |
559 | *fp = fa->fa_next; | |
560 | kmem_cache_free(fasync_cache, fa); | |
561 | result = 1; | |
562 | } | |
563 | goto out; | |
564 | } | |
565 | } | |
566 | ||
567 | if (on) { | |
568 | new->magic = FASYNC_MAGIC; | |
569 | new->fa_file = filp; | |
570 | new->fa_fd = fd; | |
571 | new->fa_next = *fapp; | |
572 | *fapp = new; | |
573 | result = 1; | |
574 | } | |
575 | out: | |
576 | write_unlock_irq(&fasync_lock); | |
577 | return result; | |
578 | } | |
579 | ||
580 | EXPORT_SYMBOL(fasync_helper); | |
581 | ||
582 | void __kill_fasync(struct fasync_struct *fa, int sig, int band) | |
583 | { | |
584 | while (fa) { | |
585 | struct fown_struct * fown; | |
586 | if (fa->magic != FASYNC_MAGIC) { | |
587 | printk(KERN_ERR "kill_fasync: bad magic number in " | |
588 | "fasync_struct!\n"); | |
589 | return; | |
590 | } | |
591 | fown = &fa->fa_file->f_owner; | |
592 | /* Don't send SIGURG to processes which have not set a | |
593 | queued signum: SIGURG has its own default signalling | |
594 | mechanism. */ | |
595 | if (!(sig == SIGURG && fown->signum == 0)) | |
596 | send_sigio(fown, fa->fa_fd, band); | |
597 | fa = fa->fa_next; | |
598 | } | |
599 | } | |
600 | ||
601 | EXPORT_SYMBOL(__kill_fasync); | |
602 | ||
603 | void kill_fasync(struct fasync_struct **fp, int sig, int band) | |
604 | { | |
605 | /* First a quick test without locking: usually | |
606 | * the list is empty. | |
607 | */ | |
608 | if (*fp) { | |
609 | read_lock(&fasync_lock); | |
610 | /* reread *fp after obtaining the lock */ | |
611 | __kill_fasync(*fp, sig, band); | |
612 | read_unlock(&fasync_lock); | |
613 | } | |
614 | } | |
615 | EXPORT_SYMBOL(kill_fasync); | |
616 | ||
617 | static int __init fasync_init(void) | |
618 | { | |
619 | fasync_cache = kmem_cache_create("fasync_cache", | |
620 | sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL, NULL); | |
621 | return 0; | |
622 | } | |
623 | ||
624 | module_init(fasync_init) |