diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/fcntl.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/fcntl.c')
-rw-r--r-- | fs/fcntl.c | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/fs/fcntl.c b/fs/fcntl.c new file mode 100644 index 000000000000..c1708066bf55 --- /dev/null +++ b/fs/fcntl.c | |||
@@ -0,0 +1,601 @@ | |||
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> | ||
12 | #include <linux/dnotify.h> | ||
13 | #include <linux/smp_lock.h> | ||
14 | #include <linux/slab.h> | ||
15 | #include <linux/module.h> | ||
16 | #include <linux/security.h> | ||
17 | #include <linux/ptrace.h> | ||
18 | |||
19 | #include <asm/poll.h> | ||
20 | #include <asm/siginfo.h> | ||
21 | #include <asm/uaccess.h> | ||
22 | |||
23 | void fastcall set_close_on_exec(unsigned int fd, int flag) | ||
24 | { | ||
25 | struct files_struct *files = current->files; | ||
26 | spin_lock(&files->file_lock); | ||
27 | if (flag) | ||
28 | FD_SET(fd, files->close_on_exec); | ||
29 | else | ||
30 | FD_CLR(fd, files->close_on_exec); | ||
31 | spin_unlock(&files->file_lock); | ||
32 | } | ||
33 | |||
34 | static inline int get_close_on_exec(unsigned int fd) | ||
35 | { | ||
36 | struct files_struct *files = current->files; | ||
37 | int res; | ||
38 | spin_lock(&files->file_lock); | ||
39 | res = FD_ISSET(fd, files->close_on_exec); | ||
40 | spin_unlock(&files->file_lock); | ||
41 | return res; | ||
42 | } | ||
43 | |||
44 | /* | ||
45 | * locate_fd finds a free file descriptor in the open_fds fdset, | ||
46 | * expanding the fd arrays if necessary. Must be called with the | ||
47 | * file_lock held for write. | ||
48 | */ | ||
49 | |||
50 | static int locate_fd(struct files_struct *files, | ||
51 | struct file *file, unsigned int orig_start) | ||
52 | { | ||
53 | unsigned int newfd; | ||
54 | unsigned int start; | ||
55 | int error; | ||
56 | |||
57 | error = -EINVAL; | ||
58 | if (orig_start >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | ||
59 | goto out; | ||
60 | |||
61 | repeat: | ||
62 | /* | ||
63 | * Someone might have closed fd's in the range | ||
64 | * orig_start..files->next_fd | ||
65 | */ | ||
66 | start = orig_start; | ||
67 | if (start < files->next_fd) | ||
68 | start = files->next_fd; | ||
69 | |||
70 | newfd = start; | ||
71 | if (start < files->max_fdset) { | ||
72 | newfd = find_next_zero_bit(files->open_fds->fds_bits, | ||
73 | files->max_fdset, start); | ||
74 | } | ||
75 | |||
76 | error = -EMFILE; | ||
77 | if (newfd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | ||
78 | goto out; | ||
79 | |||
80 | error = expand_files(files, newfd); | ||
81 | if (error < 0) | ||
82 | goto out; | ||
83 | |||
84 | /* | ||
85 | * If we needed to expand the fs array we | ||
86 | * might have blocked - try again. | ||
87 | */ | ||
88 | if (error) | ||
89 | goto repeat; | ||
90 | |||
91 | if (start <= files->next_fd) | ||
92 | files->next_fd = newfd + 1; | ||
93 | |||
94 | error = newfd; | ||
95 | |||
96 | out: | ||
97 | return error; | ||
98 | } | ||
99 | |||
100 | static int dupfd(struct file *file, unsigned int start) | ||
101 | { | ||
102 | struct files_struct * files = current->files; | ||
103 | int fd; | ||
104 | |||
105 | spin_lock(&files->file_lock); | ||
106 | fd = locate_fd(files, file, start); | ||
107 | if (fd >= 0) { | ||
108 | FD_SET(fd, files->open_fds); | ||
109 | FD_CLR(fd, files->close_on_exec); | ||
110 | spin_unlock(&files->file_lock); | ||
111 | fd_install(fd, file); | ||
112 | } else { | ||
113 | spin_unlock(&files->file_lock); | ||
114 | fput(file); | ||
115 | } | ||
116 | |||
117 | return fd; | ||
118 | } | ||
119 | |||
120 | asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd) | ||
121 | { | ||
122 | int err = -EBADF; | ||
123 | struct file * file, *tofree; | ||
124 | struct files_struct * files = current->files; | ||
125 | |||
126 | spin_lock(&files->file_lock); | ||
127 | if (!(file = fcheck(oldfd))) | ||
128 | goto out_unlock; | ||
129 | err = newfd; | ||
130 | if (newfd == oldfd) | ||
131 | goto out_unlock; | ||
132 | err = -EBADF; | ||
133 | if (newfd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur) | ||
134 | goto out_unlock; | ||
135 | get_file(file); /* We are now finished with oldfd */ | ||
136 | |||
137 | err = expand_files(files, newfd); | ||
138 | if (err < 0) | ||
139 | goto out_fput; | ||
140 | |||
141 | /* To avoid races with open() and dup(), we will mark the fd as | ||
142 | * in-use in the open-file bitmap throughout the entire dup2() | ||
143 | * process. This is quite safe: do_close() uses the fd array | ||
144 | * entry, not the bitmap, to decide what work needs to be | ||
145 | * done. --sct */ | ||
146 | /* Doesn't work. open() might be there first. --AV */ | ||
147 | |||
148 | /* Yes. It's a race. In user space. Nothing sane to do */ | ||
149 | err = -EBUSY; | ||
150 | tofree = files->fd[newfd]; | ||
151 | if (!tofree && FD_ISSET(newfd, files->open_fds)) | ||
152 | goto out_fput; | ||
153 | |||
154 | files->fd[newfd] = file; | ||
155 | FD_SET(newfd, files->open_fds); | ||
156 | FD_CLR(newfd, files->close_on_exec); | ||
157 | spin_unlock(&files->file_lock); | ||
158 | |||
159 | if (tofree) | ||
160 | filp_close(tofree, files); | ||
161 | err = newfd; | ||
162 | out: | ||
163 | return err; | ||
164 | out_unlock: | ||
165 | spin_unlock(&files->file_lock); | ||
166 | goto out; | ||
167 | |||
168 | out_fput: | ||
169 | spin_unlock(&files->file_lock); | ||
170 | fput(file); | ||
171 | goto out; | ||
172 | } | ||
173 | |||
174 | asmlinkage long sys_dup(unsigned int fildes) | ||
175 | { | ||
176 | int ret = -EBADF; | ||
177 | struct file * file = fget(fildes); | ||
178 | |||
179 | if (file) | ||
180 | ret = dupfd(file, 0); | ||
181 | return ret; | ||
182 | } | ||
183 | |||
184 | #define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | FASYNC | O_DIRECT | O_NOATIME) | ||
185 | |||
186 | static int setfl(int fd, struct file * filp, unsigned long arg) | ||
187 | { | ||
188 | struct inode * inode = filp->f_dentry->d_inode; | ||
189 | int error = 0; | ||
190 | |||
191 | /* O_APPEND cannot be cleared if the file is marked as append-only */ | ||
192 | if (!(arg & O_APPEND) && IS_APPEND(inode)) | ||
193 | return -EPERM; | ||
194 | |||
195 | /* O_NOATIME can only be set by the owner or superuser */ | ||
196 | if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME)) | ||
197 | if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER)) | ||
198 | return -EPERM; | ||
199 | |||
200 | /* required for strict SunOS emulation */ | ||
201 | if (O_NONBLOCK != O_NDELAY) | ||
202 | if (arg & O_NDELAY) | ||
203 | arg |= O_NONBLOCK; | ||
204 | |||
205 | if (arg & O_DIRECT) { | ||
206 | if (!filp->f_mapping || !filp->f_mapping->a_ops || | ||
207 | !filp->f_mapping->a_ops->direct_IO) | ||
208 | return -EINVAL; | ||
209 | } | ||
210 | |||
211 | if (filp->f_op && filp->f_op->check_flags) | ||
212 | error = filp->f_op->check_flags(arg); | ||
213 | if (error) | ||
214 | return error; | ||
215 | |||
216 | lock_kernel(); | ||
217 | if ((arg ^ filp->f_flags) & FASYNC) { | ||
218 | if (filp->f_op && filp->f_op->fasync) { | ||
219 | error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0); | ||
220 | if (error < 0) | ||
221 | goto out; | ||
222 | } | ||
223 | } | ||
224 | |||
225 | filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK); | ||
226 | out: | ||
227 | unlock_kernel(); | ||
228 | return error; | ||
229 | } | ||
230 | |||
231 | static void f_modown(struct file *filp, unsigned long pid, | ||
232 | uid_t uid, uid_t euid, int force) | ||
233 | { | ||
234 | write_lock_irq(&filp->f_owner.lock); | ||
235 | if (force || !filp->f_owner.pid) { | ||
236 | filp->f_owner.pid = pid; | ||
237 | filp->f_owner.uid = uid; | ||
238 | filp->f_owner.euid = euid; | ||
239 | } | ||
240 | write_unlock_irq(&filp->f_owner.lock); | ||
241 | } | ||
242 | |||
243 | int f_setown(struct file *filp, unsigned long arg, int force) | ||
244 | { | ||
245 | int err; | ||
246 | |||
247 | err = security_file_set_fowner(filp); | ||
248 | if (err) | ||
249 | return err; | ||
250 | |||
251 | f_modown(filp, arg, current->uid, current->euid, force); | ||
252 | return 0; | ||
253 | } | ||
254 | |||
255 | EXPORT_SYMBOL(f_setown); | ||
256 | |||
257 | void f_delown(struct file *filp) | ||
258 | { | ||
259 | f_modown(filp, 0, 0, 0, 1); | ||
260 | } | ||
261 | |||
262 | static long do_fcntl(int fd, unsigned int cmd, unsigned long arg, | ||
263 | struct file *filp) | ||
264 | { | ||
265 | long err = -EINVAL; | ||
266 | |||
267 | switch (cmd) { | ||
268 | case F_DUPFD: | ||
269 | get_file(filp); | ||
270 | err = dupfd(filp, arg); | ||
271 | break; | ||
272 | case F_GETFD: | ||
273 | err = get_close_on_exec(fd) ? FD_CLOEXEC : 0; | ||
274 | break; | ||
275 | case F_SETFD: | ||
276 | err = 0; | ||
277 | set_close_on_exec(fd, arg & FD_CLOEXEC); | ||
278 | break; | ||
279 | case F_GETFL: | ||
280 | err = filp->f_flags; | ||
281 | break; | ||
282 | case F_SETFL: | ||
283 | err = setfl(fd, filp, arg); | ||
284 | break; | ||
285 | case F_GETLK: | ||
286 | err = fcntl_getlk(filp, (struct flock __user *) arg); | ||
287 | break; | ||
288 | case F_SETLK: | ||
289 | case F_SETLKW: | ||
290 | err = fcntl_setlk(filp, cmd, (struct flock __user *) arg); | ||
291 | break; | ||
292 | case F_GETOWN: | ||
293 | /* | ||
294 | * XXX If f_owner is a process group, the | ||
295 | * negative return value will get converted | ||
296 | * into an error. Oops. If we keep the | ||
297 | * current syscall conventions, the only way | ||
298 | * to fix this will be in libc. | ||
299 | */ | ||
300 | err = filp->f_owner.pid; | ||
301 | force_successful_syscall_return(); | ||
302 | break; | ||
303 | case F_SETOWN: | ||
304 | err = f_setown(filp, arg, 1); | ||
305 | break; | ||
306 | case F_GETSIG: | ||
307 | err = filp->f_owner.signum; | ||
308 | break; | ||
309 | case F_SETSIG: | ||
310 | /* arg == 0 restores default behaviour. */ | ||
311 | if (arg < 0 || arg > _NSIG) { | ||
312 | break; | ||
313 | } | ||
314 | err = 0; | ||
315 | filp->f_owner.signum = arg; | ||
316 | break; | ||
317 | case F_GETLEASE: | ||
318 | err = fcntl_getlease(filp); | ||
319 | break; | ||
320 | case F_SETLEASE: | ||
321 | err = fcntl_setlease(fd, filp, arg); | ||
322 | break; | ||
323 | case F_NOTIFY: | ||
324 | err = fcntl_dirnotify(fd, filp, arg); | ||
325 | break; | ||
326 | default: | ||
327 | break; | ||
328 | } | ||
329 | return err; | ||
330 | } | ||
331 | |||
332 | asmlinkage long sys_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg) | ||
333 | { | ||
334 | struct file *filp; | ||
335 | long err = -EBADF; | ||
336 | |||
337 | filp = fget(fd); | ||
338 | if (!filp) | ||
339 | goto out; | ||
340 | |||
341 | err = security_file_fcntl(filp, cmd, arg); | ||
342 | if (err) { | ||
343 | fput(filp); | ||
344 | return err; | ||
345 | } | ||
346 | |||
347 | err = do_fcntl(fd, cmd, arg, filp); | ||
348 | |||
349 | fput(filp); | ||
350 | out: | ||
351 | return err; | ||
352 | } | ||
353 | |||
354 | #if BITS_PER_LONG == 32 | ||
355 | asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg) | ||
356 | { | ||
357 | struct file * filp; | ||
358 | long err; | ||
359 | |||
360 | err = -EBADF; | ||
361 | filp = fget(fd); | ||
362 | if (!filp) | ||
363 | goto out; | ||
364 | |||
365 | err = security_file_fcntl(filp, cmd, arg); | ||
366 | if (err) { | ||
367 | fput(filp); | ||
368 | return err; | ||
369 | } | ||
370 | err = -EBADF; | ||
371 | |||
372 | switch (cmd) { | ||
373 | case F_GETLK64: | ||
374 | err = fcntl_getlk64(filp, (struct flock64 __user *) arg); | ||
375 | break; | ||
376 | case F_SETLK64: | ||
377 | case F_SETLKW64: | ||
378 | err = fcntl_setlk64(filp, cmd, (struct flock64 __user *) arg); | ||
379 | break; | ||
380 | default: | ||
381 | err = do_fcntl(fd, cmd, arg, filp); | ||
382 | break; | ||
383 | } | ||
384 | fput(filp); | ||
385 | out: | ||
386 | return err; | ||
387 | } | ||
388 | #endif | ||
389 | |||
390 | /* Table to convert sigio signal codes into poll band bitmaps */ | ||
391 | |||
392 | static long band_table[NSIGPOLL] = { | ||
393 | POLLIN | POLLRDNORM, /* POLL_IN */ | ||
394 | POLLOUT | POLLWRNORM | POLLWRBAND, /* POLL_OUT */ | ||
395 | POLLIN | POLLRDNORM | POLLMSG, /* POLL_MSG */ | ||
396 | POLLERR, /* POLL_ERR */ | ||
397 | POLLPRI | POLLRDBAND, /* POLL_PRI */ | ||
398 | POLLHUP | POLLERR /* POLL_HUP */ | ||
399 | }; | ||
400 | |||
401 | static inline int sigio_perm(struct task_struct *p, | ||
402 | struct fown_struct *fown, int sig) | ||
403 | { | ||
404 | return (((fown->euid == 0) || | ||
405 | (fown->euid == p->suid) || (fown->euid == p->uid) || | ||
406 | (fown->uid == p->suid) || (fown->uid == p->uid)) && | ||
407 | !security_file_send_sigiotask(p, fown, sig)); | ||
408 | } | ||
409 | |||
410 | static void send_sigio_to_task(struct task_struct *p, | ||
411 | struct fown_struct *fown, | ||
412 | int fd, | ||
413 | int reason) | ||
414 | { | ||
415 | if (!sigio_perm(p, fown, fown->signum)) | ||
416 | return; | ||
417 | |||
418 | switch (fown->signum) { | ||
419 | siginfo_t si; | ||
420 | default: | ||
421 | /* Queue a rt signal with the appropriate fd as its | ||
422 | value. We use SI_SIGIO as the source, not | ||
423 | SI_KERNEL, since kernel signals always get | ||
424 | delivered even if we can't queue. Failure to | ||
425 | queue in this case _should_ be reported; we fall | ||
426 | back to SIGIO in that case. --sct */ | ||
427 | si.si_signo = fown->signum; | ||
428 | si.si_errno = 0; | ||
429 | si.si_code = reason; | ||
430 | /* Make sure we are called with one of the POLL_* | ||
431 | reasons, otherwise we could leak kernel stack into | ||
432 | userspace. */ | ||
433 | if ((reason & __SI_MASK) != __SI_POLL) | ||
434 | BUG(); | ||
435 | if (reason - POLL_IN >= NSIGPOLL) | ||
436 | si.si_band = ~0L; | ||
437 | else | ||
438 | si.si_band = band_table[reason - POLL_IN]; | ||
439 | si.si_fd = fd; | ||
440 | if (!send_sig_info(fown->signum, &si, p)) | ||
441 | break; | ||
442 | /* fall-through: fall back on the old plain SIGIO signal */ | ||
443 | case 0: | ||
444 | send_group_sig_info(SIGIO, SEND_SIG_PRIV, p); | ||
445 | } | ||
446 | } | ||
447 | |||
448 | void send_sigio(struct fown_struct *fown, int fd, int band) | ||
449 | { | ||
450 | struct task_struct *p; | ||
451 | int pid; | ||
452 | |||
453 | read_lock(&fown->lock); | ||
454 | pid = fown->pid; | ||
455 | if (!pid) | ||
456 | goto out_unlock_fown; | ||
457 | |||
458 | read_lock(&tasklist_lock); | ||
459 | if (pid > 0) { | ||
460 | p = find_task_by_pid(pid); | ||
461 | if (p) { | ||
462 | send_sigio_to_task(p, fown, fd, band); | ||
463 | } | ||
464 | } else { | ||
465 | do_each_task_pid(-pid, PIDTYPE_PGID, p) { | ||
466 | send_sigio_to_task(p, fown, fd, band); | ||
467 | } while_each_task_pid(-pid, PIDTYPE_PGID, p); | ||
468 | } | ||
469 | read_unlock(&tasklist_lock); | ||
470 | out_unlock_fown: | ||
471 | read_unlock(&fown->lock); | ||
472 | } | ||
473 | |||
474 | static void send_sigurg_to_task(struct task_struct *p, | ||
475 | struct fown_struct *fown) | ||
476 | { | ||
477 | if (sigio_perm(p, fown, SIGURG)) | ||
478 | send_group_sig_info(SIGURG, SEND_SIG_PRIV, p); | ||
479 | } | ||
480 | |||
481 | int send_sigurg(struct fown_struct *fown) | ||
482 | { | ||
483 | struct task_struct *p; | ||
484 | int pid, ret = 0; | ||
485 | |||
486 | read_lock(&fown->lock); | ||
487 | pid = fown->pid; | ||
488 | if (!pid) | ||
489 | goto out_unlock_fown; | ||
490 | |||
491 | ret = 1; | ||
492 | |||
493 | read_lock(&tasklist_lock); | ||
494 | if (pid > 0) { | ||
495 | p = find_task_by_pid(pid); | ||
496 | if (p) { | ||
497 | send_sigurg_to_task(p, fown); | ||
498 | } | ||
499 | } else { | ||
500 | do_each_task_pid(-pid, PIDTYPE_PGID, p) { | ||
501 | send_sigurg_to_task(p, fown); | ||
502 | } while_each_task_pid(-pid, PIDTYPE_PGID, p); | ||
503 | } | ||
504 | read_unlock(&tasklist_lock); | ||
505 | out_unlock_fown: | ||
506 | read_unlock(&fown->lock); | ||
507 | return ret; | ||
508 | } | ||
509 | |||
510 | static DEFINE_RWLOCK(fasync_lock); | ||
511 | static kmem_cache_t *fasync_cache; | ||
512 | |||
513 | /* | ||
514 | * fasync_helper() is used by some character device drivers (mainly mice) | ||
515 | * to set up the fasync queue. It returns negative on error, 0 if it did | ||
516 | * no changes and positive if it added/deleted the entry. | ||
517 | */ | ||
518 | int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp) | ||
519 | { | ||
520 | struct fasync_struct *fa, **fp; | ||
521 | struct fasync_struct *new = NULL; | ||
522 | int result = 0; | ||
523 | |||
524 | if (on) { | ||
525 | new = kmem_cache_alloc(fasync_cache, SLAB_KERNEL); | ||
526 | if (!new) | ||
527 | return -ENOMEM; | ||
528 | } | ||
529 | write_lock_irq(&fasync_lock); | ||
530 | for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) { | ||
531 | if (fa->fa_file == filp) { | ||
532 | if(on) { | ||
533 | fa->fa_fd = fd; | ||
534 | kmem_cache_free(fasync_cache, new); | ||
535 | } else { | ||
536 | *fp = fa->fa_next; | ||
537 | kmem_cache_free(fasync_cache, fa); | ||
538 | result = 1; | ||
539 | } | ||
540 | goto out; | ||
541 | } | ||
542 | } | ||
543 | |||
544 | if (on) { | ||
545 | new->magic = FASYNC_MAGIC; | ||
546 | new->fa_file = filp; | ||
547 | new->fa_fd = fd; | ||
548 | new->fa_next = *fapp; | ||
549 | *fapp = new; | ||
550 | result = 1; | ||
551 | } | ||
552 | out: | ||
553 | write_unlock_irq(&fasync_lock); | ||
554 | return result; | ||
555 | } | ||
556 | |||
557 | EXPORT_SYMBOL(fasync_helper); | ||
558 | |||
559 | void __kill_fasync(struct fasync_struct *fa, int sig, int band) | ||
560 | { | ||
561 | while (fa) { | ||
562 | struct fown_struct * fown; | ||
563 | if (fa->magic != FASYNC_MAGIC) { | ||
564 | printk(KERN_ERR "kill_fasync: bad magic number in " | ||
565 | "fasync_struct!\n"); | ||
566 | return; | ||
567 | } | ||
568 | fown = &fa->fa_file->f_owner; | ||
569 | /* Don't send SIGURG to processes which have not set a | ||
570 | queued signum: SIGURG has its own default signalling | ||
571 | mechanism. */ | ||
572 | if (!(sig == SIGURG && fown->signum == 0)) | ||
573 | send_sigio(fown, fa->fa_fd, band); | ||
574 | fa = fa->fa_next; | ||
575 | } | ||
576 | } | ||
577 | |||
578 | EXPORT_SYMBOL(__kill_fasync); | ||
579 | |||
580 | void kill_fasync(struct fasync_struct **fp, int sig, int band) | ||
581 | { | ||
582 | /* First a quick test without locking: usually | ||
583 | * the list is empty. | ||
584 | */ | ||
585 | if (*fp) { | ||
586 | read_lock(&fasync_lock); | ||
587 | /* reread *fp after obtaining the lock */ | ||
588 | __kill_fasync(*fp, sig, band); | ||
589 | read_unlock(&fasync_lock); | ||
590 | } | ||
591 | } | ||
592 | EXPORT_SYMBOL(kill_fasync); | ||
593 | |||
594 | static int __init fasync_init(void) | ||
595 | { | ||
596 | fasync_cache = kmem_cache_create("fasync_cache", | ||
597 | sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL, NULL); | ||
598 | return 0; | ||
599 | } | ||
600 | |||
601 | module_init(fasync_init) | ||