linux/fs/fcntl.c
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   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/fdtable.h>
  13#include <linux/capability.h>
  14#include <linux/dnotify.h>
  15#include <linux/slab.h>
  16#include <linux/module.h>
  17#include <linux/pipe_fs_i.h>
  18#include <linux/security.h>
  19#include <linux/ptrace.h>
  20#include <linux/signal.h>
  21#include <linux/rcupdate.h>
  22#include <linux/pid_namespace.h>
  23#include <linux/user_namespace.h>
  24
  25#include <asm/poll.h>
  26#include <asm/siginfo.h>
  27#include <asm/uaccess.h>
  28
  29#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
  30
  31static int setfl(int fd, struct file * filp, unsigned long arg)
  32{
  33        struct inode * inode = file_inode(filp);
  34        int error = 0;
  35
  36        /*
  37         * O_APPEND cannot be cleared if the file is marked as append-only
  38         * and the file is open for write.
  39         */
  40        if (((arg ^ filp->f_flags) & O_APPEND) && IS_APPEND(inode))
  41                return -EPERM;
  42
  43        /* O_NOATIME can only be set by the owner or superuser */
  44        if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
  45                if (!inode_owner_or_capable(inode))
  46                        return -EPERM;
  47
  48        /* required for strict SunOS emulation */
  49        if (O_NONBLOCK != O_NDELAY)
  50               if (arg & O_NDELAY)
  51                   arg |= O_NONBLOCK;
  52
  53        if (arg & O_DIRECT) {
  54                if (!filp->f_mapping || !filp->f_mapping->a_ops ||
  55                        !filp->f_mapping->a_ops->direct_IO)
  56                                return -EINVAL;
  57        }
  58
  59        if (filp->f_op && filp->f_op->check_flags)
  60                error = filp->f_op->check_flags(arg);
  61        if (error)
  62                return error;
  63
  64        /*
  65         * ->fasync() is responsible for setting the FASYNC bit.
  66         */
  67        if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op &&
  68                        filp->f_op->fasync) {
  69                error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
  70                if (error < 0)
  71                        goto out;
  72                if (error > 0)
  73                        error = 0;
  74        }
  75        spin_lock(&filp->f_lock);
  76        filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
  77        spin_unlock(&filp->f_lock);
  78
  79 out:
  80        return error;
  81}
  82
  83static void f_modown(struct file *filp, struct pid *pid, enum pid_type type,
  84                     int force)
  85{
  86        write_lock_irq(&filp->f_owner.lock);
  87        if (force || !filp->f_owner.pid) {
  88                put_pid(filp->f_owner.pid);
  89                filp->f_owner.pid = get_pid(pid);
  90                filp->f_owner.pid_type = type;
  91
  92                if (pid) {
  93                        const struct cred *cred = current_cred();
  94                        filp->f_owner.uid = cred->uid;
  95                        filp->f_owner.euid = cred->euid;
  96                }
  97        }
  98        write_unlock_irq(&filp->f_owner.lock);
  99}
 100
 101int __f_setown(struct file *filp, struct pid *pid, enum pid_type type,
 102                int force)
 103{
 104        int err;
 105
 106        err = security_file_set_fowner(filp);
 107        if (err)
 108                return err;
 109
 110        f_modown(filp, pid, type, force);
 111        return 0;
 112}
 113EXPORT_SYMBOL(__f_setown);
 114
 115int f_setown(struct file *filp, unsigned long arg, int force)
 116{
 117        enum pid_type type;
 118        struct pid *pid;
 119        int who = arg;
 120        int result;
 121        type = PIDTYPE_PID;
 122        if (who < 0) {
 123                type = PIDTYPE_PGID;
 124                who = -who;
 125        }
 126        rcu_read_lock();
 127        pid = find_vpid(who);
 128        result = __f_setown(filp, pid, type, force);
 129        rcu_read_unlock();
 130        return result;
 131}
 132EXPORT_SYMBOL(f_setown);
 133
 134void f_delown(struct file *filp)
 135{
 136        f_modown(filp, NULL, PIDTYPE_PID, 1);
 137}
 138
 139pid_t f_getown(struct file *filp)
 140{
 141        pid_t pid;
 142        read_lock(&filp->f_owner.lock);
 143        pid = pid_vnr(filp->f_owner.pid);
 144        if (filp->f_owner.pid_type == PIDTYPE_PGID)
 145                pid = -pid;
 146        read_unlock(&filp->f_owner.lock);
 147        return pid;
 148}
 149
 150static int f_setown_ex(struct file *filp, unsigned long arg)
 151{
 152        struct f_owner_ex __user *owner_p = (void __user *)arg;
 153        struct f_owner_ex owner;
 154        struct pid *pid;
 155        int type;
 156        int ret;
 157
 158        ret = copy_from_user(&owner, owner_p, sizeof(owner));
 159        if (ret)
 160                return -EFAULT;
 161
 162        switch (owner.type) {
 163        case F_OWNER_TID:
 164                type = PIDTYPE_MAX;
 165                break;
 166
 167        case F_OWNER_PID:
 168                type = PIDTYPE_PID;
 169                break;
 170
 171        case F_OWNER_PGRP:
 172                type = PIDTYPE_PGID;
 173                break;
 174
 175        default:
 176                return -EINVAL;
 177        }
 178
 179        rcu_read_lock();
 180        pid = find_vpid(owner.pid);
 181        if (owner.pid && !pid)
 182                ret = -ESRCH;
 183        else
 184                ret = __f_setown(filp, pid, type, 1);
 185        rcu_read_unlock();
 186
 187        return ret;
 188}
 189
 190static int f_getown_ex(struct file *filp, unsigned long arg)
 191{
 192        struct f_owner_ex __user *owner_p = (void __user *)arg;
 193        struct f_owner_ex owner;
 194        int ret = 0;
 195
 196        read_lock(&filp->f_owner.lock);
 197        owner.pid = pid_vnr(filp->f_owner.pid);
 198        switch (filp->f_owner.pid_type) {
 199        case PIDTYPE_MAX:
 200                owner.type = F_OWNER_TID;
 201                break;
 202
 203        case PIDTYPE_PID:
 204                owner.type = F_OWNER_PID;
 205                break;
 206
 207        case PIDTYPE_PGID:
 208                owner.type = F_OWNER_PGRP;
 209                break;
 210
 211        default:
 212                WARN_ON(1);
 213                ret = -EINVAL;
 214                break;
 215        }
 216        read_unlock(&filp->f_owner.lock);
 217
 218        if (!ret) {
 219                ret = copy_to_user(owner_p, &owner, sizeof(owner));
 220                if (ret)
 221                        ret = -EFAULT;
 222        }
 223        return ret;
 224}
 225
 226#ifdef CONFIG_CHECKPOINT_RESTORE
 227static int f_getowner_uids(struct file *filp, unsigned long arg)
 228{
 229        struct user_namespace *user_ns = current_user_ns();
 230        uid_t __user *dst = (void __user *)arg;
 231        uid_t src[2];
 232        int err;
 233
 234        read_lock(&filp->f_owner.lock);
 235        src[0] = from_kuid(user_ns, filp->f_owner.uid);
 236        src[1] = from_kuid(user_ns, filp->f_owner.euid);
 237        read_unlock(&filp->f_owner.lock);
 238
 239        err  = put_user(src[0], &dst[0]);
 240        err |= put_user(src[1], &dst[1]);
 241
 242        return err;
 243}
 244#else
 245static int f_getowner_uids(struct file *filp, unsigned long arg)
 246{
 247        return -EINVAL;
 248}
 249#endif
 250
 251static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 252                struct file *filp)
 253{
 254        long err = -EINVAL;
 255
 256        switch (cmd) {
 257        case F_DUPFD:
 258                err = f_dupfd(arg, filp, 0);
 259                break;
 260        case F_DUPFD_CLOEXEC:
 261                err = f_dupfd(arg, filp, O_CLOEXEC);
 262                break;
 263        case F_GETFD:
 264                err = get_close_on_exec(fd) ? FD_CLOEXEC : 0;
 265                break;
 266        case F_SETFD:
 267                err = 0;
 268                set_close_on_exec(fd, arg & FD_CLOEXEC);
 269                break;
 270        case F_GETFL:
 271                err = filp->f_flags;
 272                break;
 273        case F_SETFL:
 274                err = setfl(fd, filp, arg);
 275                break;
 276        case F_GETLK:
 277                err = fcntl_getlk(filp, (struct flock __user *) arg);
 278                break;
 279        case F_SETLK:
 280        case F_SETLKW:
 281                err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
 282                break;
 283        case F_GETOWN:
 284                /*
 285                 * XXX If f_owner is a process group, the
 286                 * negative return value will get converted
 287                 * into an error.  Oops.  If we keep the
 288                 * current syscall conventions, the only way
 289                 * to fix this will be in libc.
 290                 */
 291                err = f_getown(filp);
 292                force_successful_syscall_return();
 293                break;
 294        case F_SETOWN:
 295                err = f_setown(filp, arg, 1);
 296                break;
 297        case F_GETOWN_EX:
 298                err = f_getown_ex(filp, arg);
 299                break;
 300        case F_SETOWN_EX:
 301                err = f_setown_ex(filp, arg);
 302                break;
 303        case F_GETOWNER_UIDS:
 304                err = f_getowner_uids(filp, arg);
 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 (!valid_signal(arg)) {
 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        case F_SETPIPE_SZ:
 327        case F_GETPIPE_SZ:
 328                err = pipe_fcntl(filp, cmd, arg);
 329                break;
 330        default:
 331                break;
 332        }
 333        return err;
 334}
 335
 336static int check_fcntl_cmd(unsigned cmd)
 337{
 338        switch (cmd) {
 339        case F_DUPFD:
 340        case F_DUPFD_CLOEXEC:
 341        case F_GETFD:
 342        case F_SETFD:
 343        case F_GETFL:
 344                return 1;
 345        }
 346        return 0;
 347}
 348
 349SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
 350{       
 351        struct fd f = fdget_raw(fd);
 352        long err = -EBADF;
 353
 354        if (!f.file)
 355                goto out;
 356
 357        if (unlikely(f.file->f_mode & FMODE_PATH)) {
 358                if (!check_fcntl_cmd(cmd))
 359                        goto out1;
 360        }
 361
 362        err = security_file_fcntl(f.file, cmd, arg);
 363        if (!err)
 364                err = do_fcntl(fd, cmd, arg, f.file);
 365
 366out1:
 367        fdput(f);
 368out:
 369        return err;
 370}
 371
 372#if BITS_PER_LONG == 32
 373SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
 374                unsigned long, arg)
 375{       
 376        struct fd f = fdget_raw(fd);
 377        long err = -EBADF;
 378
 379        if (!f.file)
 380                goto out;
 381
 382        if (unlikely(f.file->f_mode & FMODE_PATH)) {
 383                if (!check_fcntl_cmd(cmd))
 384                        goto out1;
 385        }
 386
 387        err = security_file_fcntl(f.file, cmd, arg);
 388        if (err)
 389                goto out1;
 390        
 391        switch (cmd) {
 392                case F_GETLK64:
 393                        err = fcntl_getlk64(f.file, (struct flock64 __user *) arg);
 394                        break;
 395                case F_SETLK64:
 396                case F_SETLKW64:
 397                        err = fcntl_setlk64(fd, f.file, cmd,
 398                                        (struct flock64 __user *) arg);
 399                        break;
 400                default:
 401                        err = do_fcntl(fd, cmd, arg, f.file);
 402                        break;
 403        }
 404out1:
 405        fdput(f);
 406out:
 407        return err;
 408}
 409#endif
 410
 411/* Table to convert sigio signal codes into poll band bitmaps */
 412
 413static const long band_table[NSIGPOLL] = {
 414        POLLIN | POLLRDNORM,                    /* POLL_IN */
 415        POLLOUT | POLLWRNORM | POLLWRBAND,      /* POLL_OUT */
 416        POLLIN | POLLRDNORM | POLLMSG,          /* POLL_MSG */
 417        POLLERR,                                /* POLL_ERR */
 418        POLLPRI | POLLRDBAND,                   /* POLL_PRI */
 419        POLLHUP | POLLERR                       /* POLL_HUP */
 420};
 421
 422static inline int sigio_perm(struct task_struct *p,
 423                             struct fown_struct *fown, int sig)
 424{
 425        const struct cred *cred;
 426        int ret;
 427
 428        rcu_read_lock();
 429        cred = __task_cred(p);
 430        ret = ((uid_eq(fown->euid, GLOBAL_ROOT_UID) ||
 431                uid_eq(fown->euid, cred->suid) || uid_eq(fown->euid, cred->uid) ||
 432                uid_eq(fown->uid,  cred->suid) || uid_eq(fown->uid,  cred->uid)) &&
 433               !security_file_send_sigiotask(p, fown, sig));
 434        rcu_read_unlock();
 435        return ret;
 436}
 437
 438static void send_sigio_to_task(struct task_struct *p,
 439                               struct fown_struct *fown,
 440                               int fd, int reason, int group)
 441{
 442        /*
 443         * F_SETSIG can change ->signum lockless in parallel, make
 444         * sure we read it once and use the same value throughout.
 445         */
 446        int signum = ACCESS_ONCE(fown->signum);
 447
 448        if (!sigio_perm(p, fown, signum))
 449                return;
 450
 451        switch (signum) {
 452                siginfo_t si;
 453                default:
 454                        /* Queue a rt signal with the appropriate fd as its
 455                           value.  We use SI_SIGIO as the source, not 
 456                           SI_KERNEL, since kernel signals always get 
 457                           delivered even if we can't queue.  Failure to
 458                           queue in this case _should_ be reported; we fall
 459                           back to SIGIO in that case. --sct */
 460                        si.si_signo = signum;
 461                        si.si_errno = 0;
 462                        si.si_code  = reason;
 463                        /* Make sure we are called with one of the POLL_*
 464                           reasons, otherwise we could leak kernel stack into
 465                           userspace.  */
 466                        BUG_ON((reason & __SI_MASK) != __SI_POLL);
 467                        if (reason - POLL_IN >= NSIGPOLL)
 468                                si.si_band  = ~0L;
 469                        else
 470                                si.si_band = band_table[reason - POLL_IN];
 471                        si.si_fd    = fd;
 472                        if (!do_send_sig_info(signum, &si, p, group))
 473                                break;
 474                /* fall-through: fall back on the old plain SIGIO signal */
 475                case 0:
 476                        do_send_sig_info(SIGIO, SEND_SIG_PRIV, p, group);
 477        }
 478}
 479
 480void send_sigio(struct fown_struct *fown, int fd, int band)
 481{
 482        struct task_struct *p;
 483        enum pid_type type;
 484        struct pid *pid;
 485        int group = 1;
 486        
 487        read_lock(&fown->lock);
 488
 489        type = fown->pid_type;
 490        if (type == PIDTYPE_MAX) {
 491                group = 0;
 492                type = PIDTYPE_PID;
 493        }
 494
 495        pid = fown->pid;
 496        if (!pid)
 497                goto out_unlock_fown;
 498        
 499        read_lock(&tasklist_lock);
 500        do_each_pid_task(pid, type, p) {
 501                send_sigio_to_task(p, fown, fd, band, group);
 502        } while_each_pid_task(pid, type, p);
 503        read_unlock(&tasklist_lock);
 504 out_unlock_fown:
 505        read_unlock(&fown->lock);
 506}
 507
 508static void send_sigurg_to_task(struct task_struct *p,
 509                                struct fown_struct *fown, int group)
 510{
 511        if (sigio_perm(p, fown, SIGURG))
 512                do_send_sig_info(SIGURG, SEND_SIG_PRIV, p, group);
 513}
 514
 515int send_sigurg(struct fown_struct *fown)
 516{
 517        struct task_struct *p;
 518        enum pid_type type;
 519        struct pid *pid;
 520        int group = 1;
 521        int ret = 0;
 522        
 523        read_lock(&fown->lock);
 524
 525        type = fown->pid_type;
 526        if (type == PIDTYPE_MAX) {
 527                group = 0;
 528                type = PIDTYPE_PID;
 529        }
 530
 531        pid = fown->pid;
 532        if (!pid)
 533                goto out_unlock_fown;
 534
 535        ret = 1;
 536        
 537        read_lock(&tasklist_lock);
 538        do_each_pid_task(pid, type, p) {
 539                send_sigurg_to_task(p, fown, group);
 540        } while_each_pid_task(pid, type, p);
 541        read_unlock(&tasklist_lock);
 542 out_unlock_fown:
 543        read_unlock(&fown->lock);
 544        return ret;
 545}
 546
 547static DEFINE_SPINLOCK(fasync_lock);
 548static struct kmem_cache *fasync_cache __read_mostly;
 549
 550static void fasync_free_rcu(struct rcu_head *head)
 551{
 552        kmem_cache_free(fasync_cache,
 553                        container_of(head, struct fasync_struct, fa_rcu));
 554}
 555
 556/*
 557 * Remove a fasync entry. If successfully removed, return
 558 * positive and clear the FASYNC flag. If no entry exists,
 559 * do nothing and return 0.
 560 *
 561 * NOTE! It is very important that the FASYNC flag always
 562 * match the state "is the filp on a fasync list".
 563 *
 564 */
 565int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)
 566{
 567        struct fasync_struct *fa, **fp;
 568        int result = 0;
 569
 570        spin_lock(&filp->f_lock);
 571        spin_lock(&fasync_lock);
 572        for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
 573                if (fa->fa_file != filp)
 574                        continue;
 575
 576                spin_lock_irq(&fa->fa_lock);
 577                fa->fa_file = NULL;
 578                spin_unlock_irq(&fa->fa_lock);
 579
 580                *fp = fa->fa_next;
 581                call_rcu(&fa->fa_rcu, fasync_free_rcu);
 582                filp->f_flags &= ~FASYNC;
 583                result = 1;
 584                break;
 585        }
 586        spin_unlock(&fasync_lock);
 587        spin_unlock(&filp->f_lock);
 588        return result;
 589}
 590
 591struct fasync_struct *fasync_alloc(void)
 592{
 593        return kmem_cache_alloc(fasync_cache, GFP_KERNEL);
 594}
 595
 596/*
 597 * NOTE! This can be used only for unused fasync entries:
 598 * entries that actually got inserted on the fasync list
 599 * need to be released by rcu - see fasync_remove_entry.
 600 */
 601void fasync_free(struct fasync_struct *new)
 602{
 603        kmem_cache_free(fasync_cache, new);
 604}
 605
 606/*
 607 * Insert a new entry into the fasync list.  Return the pointer to the
 608 * old one if we didn't use the new one.
 609 *
 610 * NOTE! It is very important that the FASYNC flag always
 611 * match the state "is the filp on a fasync list".
 612 */
 613struct fasync_struct *fasync_insert_entry(int fd, struct file *filp, struct fasync_struct **fapp, struct fasync_struct *new)
 614{
 615        struct fasync_struct *fa, **fp;
 616
 617        spin_lock(&filp->f_lock);
 618        spin_lock(&fasync_lock);
 619        for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
 620                if (fa->fa_file != filp)
 621                        continue;
 622
 623                spin_lock_irq(&fa->fa_lock);
 624                fa->fa_fd = fd;
 625                spin_unlock_irq(&fa->fa_lock);
 626                goto out;
 627        }
 628
 629        spin_lock_init(&new->fa_lock);
 630        new->magic = FASYNC_MAGIC;
 631        new->fa_file = filp;
 632        new->fa_fd = fd;
 633        new->fa_next = *fapp;
 634        rcu_assign_pointer(*fapp, new);
 635        filp->f_flags |= FASYNC;
 636
 637out:
 638        spin_unlock(&fasync_lock);
 639        spin_unlock(&filp->f_lock);
 640        return fa;
 641}
 642
 643/*
 644 * Add a fasync entry. Return negative on error, positive if
 645 * added, and zero if did nothing but change an existing one.
 646 */
 647static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)
 648{
 649        struct fasync_struct *new;
 650
 651        new = fasync_alloc();
 652        if (!new)
 653                return -ENOMEM;
 654
 655        /*
 656         * fasync_insert_entry() returns the old (update) entry if
 657         * it existed.
 658         *
 659         * So free the (unused) new entry and return 0 to let the
 660         * caller know that we didn't add any new fasync entries.
 661         */
 662        if (fasync_insert_entry(fd, filp, fapp, new)) {
 663                fasync_free(new);
 664                return 0;
 665        }
 666
 667        return 1;
 668}
 669
 670/*
 671 * fasync_helper() is used by almost all character device drivers
 672 * to set up the fasync queue, and for regular files by the file
 673 * lease code. It returns negative on error, 0 if it did no changes
 674 * and positive if it added/deleted the entry.
 675 */
 676int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
 677{
 678        if (!on)
 679                return fasync_remove_entry(filp, fapp);
 680        return fasync_add_entry(fd, filp, fapp);
 681}
 682
 683EXPORT_SYMBOL(fasync_helper);
 684
 685/*
 686 * rcu_read_lock() is held
 687 */
 688static void kill_fasync_rcu(struct fasync_struct *fa, int sig, int band)
 689{
 690        while (fa) {
 691                struct fown_struct *fown;
 692                unsigned long flags;
 693
 694                if (fa->magic != FASYNC_MAGIC) {
 695                        printk(KERN_ERR "kill_fasync: bad magic number in "
 696                               "fasync_struct!\n");
 697                        return;
 698                }
 699                spin_lock_irqsave(&fa->fa_lock, flags);
 700                if (fa->fa_file) {
 701                        fown = &fa->fa_file->f_owner;
 702                        /* Don't send SIGURG to processes which have not set a
 703                           queued signum: SIGURG has its own default signalling
 704                           mechanism. */
 705                        if (!(sig == SIGURG && fown->signum == 0))
 706                                send_sigio(fown, fa->fa_fd, band);
 707                }
 708                spin_unlock_irqrestore(&fa->fa_lock, flags);
 709                fa = rcu_dereference(fa->fa_next);
 710        }
 711}
 712
 713void kill_fasync(struct fasync_struct **fp, int sig, int band)
 714{
 715        /* First a quick test without locking: usually
 716         * the list is empty.
 717         */
 718        if (*fp) {
 719                rcu_read_lock();
 720                kill_fasync_rcu(rcu_dereference(*fp), sig, band);
 721                rcu_read_unlock();
 722        }
 723}
 724EXPORT_SYMBOL(kill_fasync);
 725
 726static int __init fcntl_init(void)
 727{
 728        /*
 729         * Please add new bits here to ensure allocation uniqueness.
 730         * Exceptions: O_NONBLOCK is a two bit define on parisc; O_NDELAY
 731         * is defined as O_NONBLOCK on some platforms and not on others.
 732         */
 733        BUILD_BUG_ON(20 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
 734                O_RDONLY        | O_WRONLY      | O_RDWR        |
 735                O_CREAT         | O_EXCL        | O_NOCTTY      |
 736                O_TRUNC         | O_APPEND      | /* O_NONBLOCK | */
 737                __O_SYNC        | O_DSYNC       | FASYNC        |
 738                O_DIRECT        | O_LARGEFILE   | O_DIRECTORY   |
 739                O_NOFOLLOW      | O_NOATIME     | O_CLOEXEC     |
 740                __FMODE_EXEC    | O_PATH        | __O_TMPFILE
 741                ));
 742
 743        fasync_cache = kmem_cache_create("fasync_cache",
 744                sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);
 745        return 0;
 746}
 747
 748module_init(fcntl_init)
 749