]>
git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - fs/open.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
7 #include <linux/string.h>
9 #include <linux/file.h>
10 #include <linux/fdtable.h>
11 #include <linux/fsnotify.h>
12 #include <linux/module.h>
13 #include <linux/tty.h>
14 #include <linux/namei.h>
15 #include <linux/backing-dev.h>
16 #include <linux/capability.h>
17 #include <linux/securebits.h>
18 #include <linux/security.h>
19 #include <linux/mount.h>
20 #include <linux/fcntl.h>
21 #include <linux/slab.h>
22 #include <asm/uaccess.h>
24 #include <linux/personality.h>
25 #include <linux/pagemap.h>
26 #include <linux/syscalls.h>
27 #include <linux/rcupdate.h>
28 #include <linux/audit.h>
29 #include <linux/falloc.h>
30 #include <linux/fs_struct.h>
31 #include <linux/ima.h>
32 #include <linux/dnotify.h>
36 int do_truncate(struct dentry
*dentry
, loff_t length
, unsigned int time_attrs
,
40 struct iattr newattrs
;
42 /* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */
46 newattrs
.ia_size
= length
;
47 newattrs
.ia_valid
= ATTR_SIZE
| time_attrs
;
49 newattrs
.ia_file
= filp
;
50 newattrs
.ia_valid
|= ATTR_FILE
;
53 /* Remove suid/sgid on truncate too */
54 ret
= should_remove_suid(dentry
);
56 newattrs
.ia_valid
|= ret
| ATTR_FORCE
;
58 mutex_lock(&dentry
->d_inode
->i_mutex
);
59 ret
= notify_change(dentry
, &newattrs
);
60 mutex_unlock(&dentry
->d_inode
->i_mutex
);
64 static long do_sys_truncate(const char __user
*pathname
, loff_t length
)
71 if (length
< 0) /* sorry, but loff_t says... */
74 error
= user_path(pathname
, &path
);
77 inode
= path
.dentry
->d_inode
;
79 /* For directories it's -EISDIR, for other non-regulars - -EINVAL */
81 if (S_ISDIR(inode
->i_mode
))
85 if (!S_ISREG(inode
->i_mode
))
88 error
= mnt_want_write(path
.mnt
);
92 error
= inode_permission(inode
, MAY_WRITE
);
94 goto mnt_drop_write_and_out
;
98 goto mnt_drop_write_and_out
;
100 error
= get_write_access(inode
);
102 goto mnt_drop_write_and_out
;
105 * Make sure that there are no leases. get_write_access() protects
106 * against the truncate racing with a lease-granting setlease().
108 error
= break_lease(inode
, O_WRONLY
);
110 goto put_write_and_out
;
112 error
= locks_verify_truncate(inode
, NULL
, length
);
114 error
= security_path_truncate(&path
);
116 error
= do_truncate(path
.dentry
, length
, 0, NULL
);
119 put_write_access(inode
);
120 mnt_drop_write_and_out
:
121 mnt_drop_write(path
.mnt
);
128 SYSCALL_DEFINE2(truncate
, const char __user
*, path
, long, length
)
130 return do_sys_truncate(path
, length
);
133 static long do_sys_ftruncate(unsigned int fd
, loff_t length
, int small
)
135 struct inode
* inode
;
136 struct dentry
*dentry
;
148 /* explicitly opened as large or we are on 64-bit box */
149 if (file
->f_flags
& O_LARGEFILE
)
152 dentry
= file
->f_path
.dentry
;
153 inode
= dentry
->d_inode
;
155 if (!S_ISREG(inode
->i_mode
) || !(file
->f_mode
& FMODE_WRITE
))
159 /* Cannot ftruncate over 2^31 bytes without large file support */
160 if (small
&& length
> MAX_NON_LFS
)
164 if (IS_APPEND(inode
))
167 error
= locks_verify_truncate(inode
, file
, length
);
169 error
= security_path_truncate(&file
->f_path
);
171 error
= do_truncate(dentry
, length
, ATTR_MTIME
|ATTR_CTIME
, file
);
178 SYSCALL_DEFINE2(ftruncate
, unsigned int, fd
, unsigned long, length
)
180 long ret
= do_sys_ftruncate(fd
, length
, 1);
181 /* avoid REGPARM breakage on x86: */
182 asmlinkage_protect(2, ret
, fd
, length
);
186 /* LFS versions of truncate are only needed on 32 bit machines */
187 #if BITS_PER_LONG == 32
188 SYSCALL_DEFINE(truncate64
)(const char __user
* path
, loff_t length
)
190 return do_sys_truncate(path
, length
);
192 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
193 asmlinkage
long SyS_truncate64(long path
, loff_t length
)
195 return SYSC_truncate64((const char __user
*) path
, length
);
197 SYSCALL_ALIAS(sys_truncate64
, SyS_truncate64
);
200 SYSCALL_DEFINE(ftruncate64
)(unsigned int fd
, loff_t length
)
202 long ret
= do_sys_ftruncate(fd
, length
, 0);
203 /* avoid REGPARM breakage on x86: */
204 asmlinkage_protect(2, ret
, fd
, length
);
207 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
208 asmlinkage
long SyS_ftruncate64(long fd
, loff_t length
)
210 return SYSC_ftruncate64((unsigned int) fd
, length
);
212 SYSCALL_ALIAS(sys_ftruncate64
, SyS_ftruncate64
);
214 #endif /* BITS_PER_LONG == 32 */
217 int do_fallocate(struct file
*file
, int mode
, loff_t offset
, loff_t len
)
219 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
222 if (offset
< 0 || len
<= 0)
225 /* Return error if mode is not supported */
226 if (mode
&& !(mode
& FALLOC_FL_KEEP_SIZE
))
229 if (!(file
->f_mode
& FMODE_WRITE
))
232 * Revalidate the write permissions, in case security policy has
233 * changed since the files were opened.
235 ret
= security_file_permission(file
, MAY_WRITE
);
239 if (S_ISFIFO(inode
->i_mode
))
243 * Let individual file system decide if it supports preallocation
244 * for directories or not.
246 if (!S_ISREG(inode
->i_mode
) && !S_ISDIR(inode
->i_mode
))
249 /* Check for wrap through zero too */
250 if (((offset
+ len
) > inode
->i_sb
->s_maxbytes
) || ((offset
+ len
) < 0))
253 if (!inode
->i_op
->fallocate
)
256 return inode
->i_op
->fallocate(inode
, mode
, offset
, len
);
259 SYSCALL_DEFINE(fallocate
)(int fd
, int mode
, loff_t offset
, loff_t len
)
266 error
= do_fallocate(file
, mode
, offset
, len
);
273 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
274 asmlinkage
long SyS_fallocate(long fd
, long mode
, loff_t offset
, loff_t len
)
276 return SYSC_fallocate((int)fd
, (int)mode
, offset
, len
);
278 SYSCALL_ALIAS(sys_fallocate
, SyS_fallocate
);
282 * access() needs to use the real uid/gid, not the effective uid/gid.
283 * We do this by temporarily clearing all FS-related capabilities and
284 * switching the fsuid/fsgid around to the real ones.
286 SYSCALL_DEFINE3(faccessat
, int, dfd
, const char __user
*, filename
, int, mode
)
288 const struct cred
*old_cred
;
289 struct cred
*override_cred
;
294 if (mode
& ~S_IRWXO
) /* where's F_OK, X_OK, W_OK, R_OK? */
297 override_cred
= prepare_creds();
301 override_cred
->fsuid
= override_cred
->uid
;
302 override_cred
->fsgid
= override_cred
->gid
;
304 if (!issecure(SECURE_NO_SETUID_FIXUP
)) {
305 /* Clear the capabilities if we switch to a non-root user */
306 if (override_cred
->uid
)
307 cap_clear(override_cred
->cap_effective
);
309 override_cred
->cap_effective
=
310 override_cred
->cap_permitted
;
313 old_cred
= override_creds(override_cred
);
315 res
= user_path_at(dfd
, filename
, LOOKUP_FOLLOW
, &path
);
319 inode
= path
.dentry
->d_inode
;
321 if ((mode
& MAY_EXEC
) && S_ISREG(inode
->i_mode
)) {
323 * MAY_EXEC on regular files is denied if the fs is mounted
324 * with the "noexec" flag.
327 if (path
.mnt
->mnt_flags
& MNT_NOEXEC
)
328 goto out_path_release
;
331 res
= inode_permission(inode
, mode
| MAY_ACCESS
);
332 /* SuS v2 requires we report a read only fs too */
333 if (res
|| !(mode
& S_IWOTH
) || special_file(inode
->i_mode
))
334 goto out_path_release
;
336 * This is a rare case where using __mnt_is_readonly()
337 * is OK without a mnt_want/drop_write() pair. Since
338 * no actual write to the fs is performed here, we do
339 * not need to telegraph to that to anyone.
341 * By doing this, we accept that this access is
342 * inherently racy and know that the fs may change
343 * state before we even see this result.
345 if (__mnt_is_readonly(path
.mnt
))
351 revert_creds(old_cred
);
352 put_cred(override_cred
);
356 SYSCALL_DEFINE2(access
, const char __user
*, filename
, int, mode
)
358 return sys_faccessat(AT_FDCWD
, filename
, mode
);
361 SYSCALL_DEFINE1(chdir
, const char __user
*, filename
)
366 error
= user_path_dir(filename
, &path
);
370 error
= inode_permission(path
.dentry
->d_inode
, MAY_EXEC
| MAY_CHDIR
);
374 set_fs_pwd(current
->fs
, &path
);
382 SYSCALL_DEFINE1(fchdir
, unsigned int, fd
)
393 inode
= file
->f_path
.dentry
->d_inode
;
396 if (!S_ISDIR(inode
->i_mode
))
399 error
= inode_permission(inode
, MAY_EXEC
| MAY_CHDIR
);
401 set_fs_pwd(current
->fs
, &file
->f_path
);
408 SYSCALL_DEFINE1(chroot
, const char __user
*, filename
)
413 error
= user_path_dir(filename
, &path
);
417 error
= inode_permission(path
.dentry
->d_inode
, MAY_EXEC
| MAY_CHDIR
);
422 if (!capable(CAP_SYS_CHROOT
))
424 error
= security_path_chroot(&path
);
428 set_fs_root(current
->fs
, &path
);
436 SYSCALL_DEFINE2(fchmod
, unsigned int, fd
, mode_t
, mode
)
438 struct inode
* inode
;
439 struct dentry
* dentry
;
442 struct iattr newattrs
;
448 dentry
= file
->f_path
.dentry
;
449 inode
= dentry
->d_inode
;
451 audit_inode(NULL
, dentry
);
453 err
= mnt_want_write_file(file
);
456 mutex_lock(&inode
->i_mutex
);
457 err
= security_path_chmod(dentry
, file
->f_vfsmnt
, mode
);
460 if (mode
== (mode_t
) -1)
461 mode
= inode
->i_mode
;
462 newattrs
.ia_mode
= (mode
& S_IALLUGO
) | (inode
->i_mode
& ~S_IALLUGO
);
463 newattrs
.ia_valid
= ATTR_MODE
| ATTR_CTIME
;
464 err
= notify_change(dentry
, &newattrs
);
466 mutex_unlock(&inode
->i_mutex
);
467 mnt_drop_write(file
->f_path
.mnt
);
474 SYSCALL_DEFINE3(fchmodat
, int, dfd
, const char __user
*, filename
, mode_t
, mode
)
479 struct iattr newattrs
;
481 error
= user_path_at(dfd
, filename
, LOOKUP_FOLLOW
, &path
);
484 inode
= path
.dentry
->d_inode
;
486 error
= mnt_want_write(path
.mnt
);
489 mutex_lock(&inode
->i_mutex
);
490 error
= security_path_chmod(path
.dentry
, path
.mnt
, mode
);
493 if (mode
== (mode_t
) -1)
494 mode
= inode
->i_mode
;
495 newattrs
.ia_mode
= (mode
& S_IALLUGO
) | (inode
->i_mode
& ~S_IALLUGO
);
496 newattrs
.ia_valid
= ATTR_MODE
| ATTR_CTIME
;
497 error
= notify_change(path
.dentry
, &newattrs
);
499 mutex_unlock(&inode
->i_mutex
);
500 mnt_drop_write(path
.mnt
);
507 SYSCALL_DEFINE2(chmod
, const char __user
*, filename
, mode_t
, mode
)
509 return sys_fchmodat(AT_FDCWD
, filename
, mode
);
512 static int chown_common(struct path
*path
, uid_t user
, gid_t group
)
514 struct inode
*inode
= path
->dentry
->d_inode
;
516 struct iattr newattrs
;
518 newattrs
.ia_valid
= ATTR_CTIME
;
519 if (user
!= (uid_t
) -1) {
520 newattrs
.ia_valid
|= ATTR_UID
;
521 newattrs
.ia_uid
= user
;
523 if (group
!= (gid_t
) -1) {
524 newattrs
.ia_valid
|= ATTR_GID
;
525 newattrs
.ia_gid
= group
;
527 if (!S_ISDIR(inode
->i_mode
))
529 ATTR_KILL_SUID
| ATTR_KILL_SGID
| ATTR_KILL_PRIV
;
530 mutex_lock(&inode
->i_mutex
);
531 error
= security_path_chown(path
, user
, group
);
533 error
= notify_change(path
->dentry
, &newattrs
);
534 mutex_unlock(&inode
->i_mutex
);
539 SYSCALL_DEFINE3(chown
, const char __user
*, filename
, uid_t
, user
, gid_t
, group
)
544 error
= user_path(filename
, &path
);
547 error
= mnt_want_write(path
.mnt
);
550 error
= chown_common(&path
, user
, group
);
551 mnt_drop_write(path
.mnt
);
558 SYSCALL_DEFINE5(fchownat
, int, dfd
, const char __user
*, filename
, uid_t
, user
,
559 gid_t
, group
, int, flag
)
565 if ((flag
& ~AT_SYMLINK_NOFOLLOW
) != 0)
568 follow
= (flag
& AT_SYMLINK_NOFOLLOW
) ? 0 : LOOKUP_FOLLOW
;
569 error
= user_path_at(dfd
, filename
, follow
, &path
);
572 error
= mnt_want_write(path
.mnt
);
575 error
= chown_common(&path
, user
, group
);
576 mnt_drop_write(path
.mnt
);
583 SYSCALL_DEFINE3(lchown
, const char __user
*, filename
, uid_t
, user
, gid_t
, group
)
588 error
= user_lpath(filename
, &path
);
591 error
= mnt_want_write(path
.mnt
);
594 error
= chown_common(&path
, user
, group
);
595 mnt_drop_write(path
.mnt
);
602 SYSCALL_DEFINE3(fchown
, unsigned int, fd
, uid_t
, user
, gid_t
, group
)
606 struct dentry
* dentry
;
612 error
= mnt_want_write_file(file
);
615 dentry
= file
->f_path
.dentry
;
616 audit_inode(NULL
, dentry
);
617 error
= chown_common(&file
->f_path
, user
, group
);
618 mnt_drop_write(file
->f_path
.mnt
);
626 * You have to be very careful that these write
627 * counts get cleaned up in error cases and
628 * upon __fput(). This should probably never
629 * be called outside of __dentry_open().
631 static inline int __get_file_write_access(struct inode
*inode
,
632 struct vfsmount
*mnt
)
635 error
= get_write_access(inode
);
639 * Do not take mount writer counts on
640 * special files since no writes to
641 * the mount itself will occur.
643 if (!special_file(inode
->i_mode
)) {
645 * Balanced in __fput()
647 error
= mnt_want_write(mnt
);
649 put_write_access(inode
);
654 static struct file
*__dentry_open(struct dentry
*dentry
, struct vfsmount
*mnt
,
656 int (*open
)(struct inode
*, struct file
*),
657 const struct cred
*cred
)
662 f
->f_mode
= OPEN_FMODE(f
->f_flags
) | FMODE_LSEEK
|
663 FMODE_PREAD
| FMODE_PWRITE
;
664 inode
= dentry
->d_inode
;
665 if (f
->f_mode
& FMODE_WRITE
) {
666 error
= __get_file_write_access(inode
, mnt
);
669 if (!special_file(inode
->i_mode
))
673 f
->f_mapping
= inode
->i_mapping
;
674 f
->f_path
.dentry
= dentry
;
677 f
->f_op
= fops_get(inode
->i_fop
);
678 file_sb_list_add(f
, inode
->i_sb
);
680 error
= security_dentry_open(f
, cred
);
684 if (!open
&& f
->f_op
)
685 open
= f
->f_op
->open
;
687 error
= open(inode
, f
);
693 f
->f_flags
&= ~(O_CREAT
| O_EXCL
| O_NOCTTY
| O_TRUNC
);
695 file_ra_state_init(&f
->f_ra
, f
->f_mapping
->host
->i_mapping
);
697 /* NB: we're sure to have correct a_ops only after f_op->open */
698 if (f
->f_flags
& O_DIRECT
) {
699 if (!f
->f_mapping
->a_ops
||
700 ((!f
->f_mapping
->a_ops
->direct_IO
) &&
701 (!f
->f_mapping
->a_ops
->get_xip_mem
))) {
703 f
= ERR_PTR(-EINVAL
);
711 if (f
->f_mode
& FMODE_WRITE
) {
712 put_write_access(inode
);
713 if (!special_file(inode
->i_mode
)) {
715 * We don't consider this a real
716 * mnt_want/drop_write() pair
717 * because it all happenend right
718 * here, so just reset the state.
725 f
->f_path
.dentry
= NULL
;
726 f
->f_path
.mnt
= NULL
;
731 return ERR_PTR(error
);
735 * lookup_instantiate_filp - instantiates the open intent filp
736 * @nd: pointer to nameidata
737 * @dentry: pointer to dentry
738 * @open: open callback
740 * Helper for filesystems that want to use lookup open intents and pass back
741 * a fully instantiated struct file to the caller.
742 * This function is meant to be called from within a filesystem's
744 * Beware of calling it for non-regular files! Those ->open methods might block
745 * (e.g. in fifo_open), leaving you with parent locked (and in case of fifo,
746 * leading to a deadlock, as nobody can open that fifo anymore, because
747 * another process to open fifo will block on locked parent when doing lookup).
748 * Note that in case of error, nd->intent.open.file is destroyed, but the
749 * path information remains valid.
750 * If the open callback is set to NULL, then the standard f_op->open()
751 * filesystem callback is substituted.
753 struct file
*lookup_instantiate_filp(struct nameidata
*nd
, struct dentry
*dentry
,
754 int (*open
)(struct inode
*, struct file
*))
756 const struct cred
*cred
= current_cred();
758 if (IS_ERR(nd
->intent
.open
.file
))
762 nd
->intent
.open
.file
= __dentry_open(dget(dentry
), mntget(nd
->path
.mnt
),
763 nd
->intent
.open
.file
,
766 return nd
->intent
.open
.file
;
768 release_open_intent(nd
);
769 nd
->intent
.open
.file
= (struct file
*)dentry
;
772 EXPORT_SYMBOL_GPL(lookup_instantiate_filp
);
775 * nameidata_to_filp - convert a nameidata to an open filp.
776 * @nd: pointer to nameidata
779 * Note that this function destroys the original nameidata
781 struct file
*nameidata_to_filp(struct nameidata
*nd
)
783 const struct cred
*cred
= current_cred();
786 /* Pick up the filp from the open intent */
787 filp
= nd
->intent
.open
.file
;
788 /* Has the filesystem initialised the file for us? */
789 if (filp
->f_path
.dentry
== NULL
) {
791 filp
= __dentry_open(nd
->path
.dentry
, nd
->path
.mnt
, filp
,
798 * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an
801 struct file
*dentry_open(struct dentry
*dentry
, struct vfsmount
*mnt
, int flags
,
802 const struct cred
*cred
)
807 validate_creds(cred
);
810 * We must always pass in a valid mount pointer. Historically
811 * callers got away with not passing it, but we must enforce this at
812 * the earliest possible point now to avoid strange problems deep in the
816 printk(KERN_WARNING
"%s called with NULL vfsmount\n", __func__
);
818 return ERR_PTR(-EINVAL
);
822 f
= get_empty_filp();
826 return ERR_PTR(error
);
830 return __dentry_open(dentry
, mnt
, f
, NULL
, cred
);
832 EXPORT_SYMBOL(dentry_open
);
834 static void __put_unused_fd(struct files_struct
*files
, unsigned int fd
)
836 struct fdtable
*fdt
= files_fdtable(files
);
837 __FD_CLR(fd
, fdt
->open_fds
);
838 if (fd
< files
->next_fd
)
842 void put_unused_fd(unsigned int fd
)
844 struct files_struct
*files
= current
->files
;
845 spin_lock(&files
->file_lock
);
846 __put_unused_fd(files
, fd
);
847 spin_unlock(&files
->file_lock
);
850 EXPORT_SYMBOL(put_unused_fd
);
853 * Install a file pointer in the fd array.
855 * The VFS is full of places where we drop the files lock between
856 * setting the open_fds bitmap and installing the file in the file
857 * array. At any such point, we are vulnerable to a dup2() race
858 * installing a file in the array before us. We need to detect this and
859 * fput() the struct file we are about to overwrite in this case.
861 * It should never happen - if we allow dup2() do it, _really_ bad things
865 void fd_install(unsigned int fd
, struct file
*file
)
867 struct files_struct
*files
= current
->files
;
869 spin_lock(&files
->file_lock
);
870 fdt
= files_fdtable(files
);
871 BUG_ON(fdt
->fd
[fd
] != NULL
);
872 rcu_assign_pointer(fdt
->fd
[fd
], file
);
873 spin_unlock(&files
->file_lock
);
876 EXPORT_SYMBOL(fd_install
);
878 long do_sys_open(int dfd
, const char __user
*filename
, int flags
, int mode
)
880 char *tmp
= getname(filename
);
881 int fd
= PTR_ERR(tmp
);
884 fd
= get_unused_fd_flags(flags
);
886 struct file
*f
= do_filp_open(dfd
, tmp
, flags
, mode
, 0);
900 SYSCALL_DEFINE3(open
, const char __user
*, filename
, int, flags
, int, mode
)
904 if (force_o_largefile())
905 flags
|= O_LARGEFILE
;
907 ret
= do_sys_open(AT_FDCWD
, filename
, flags
, mode
);
908 /* avoid REGPARM breakage on x86: */
909 asmlinkage_protect(3, ret
, filename
, flags
, mode
);
913 SYSCALL_DEFINE4(openat
, int, dfd
, const char __user
*, filename
, int, flags
,
918 if (force_o_largefile())
919 flags
|= O_LARGEFILE
;
921 ret
= do_sys_open(dfd
, filename
, flags
, mode
);
922 /* avoid REGPARM breakage on x86: */
923 asmlinkage_protect(4, ret
, dfd
, filename
, flags
, mode
);
930 * For backward compatibility? Maybe this should be moved
931 * into arch/i386 instead?
933 SYSCALL_DEFINE2(creat
, const char __user
*, pathname
, int, mode
)
935 return sys_open(pathname
, O_CREAT
| O_WRONLY
| O_TRUNC
, mode
);
941 * "id" is the POSIX thread ID. We use the
942 * files pointer for this..
944 int filp_close(struct file
*filp
, fl_owner_t id
)
948 if (!file_count(filp
)) {
949 printk(KERN_ERR
"VFS: Close: file count is 0\n");
953 if (filp
->f_op
&& filp
->f_op
->flush
)
954 retval
= filp
->f_op
->flush(filp
, id
);
956 dnotify_flush(filp
, id
);
957 locks_remove_posix(filp
, id
);
962 EXPORT_SYMBOL(filp_close
);
965 * Careful here! We test whether the file pointer is NULL before
966 * releasing the fd. This ensures that one clone task can't release
967 * an fd while another clone is opening it.
969 SYSCALL_DEFINE1(close
, unsigned int, fd
)
972 struct files_struct
*files
= current
->files
;
976 spin_lock(&files
->file_lock
);
977 fdt
= files_fdtable(files
);
978 if (fd
>= fdt
->max_fds
)
983 rcu_assign_pointer(fdt
->fd
[fd
], NULL
);
984 FD_CLR(fd
, fdt
->close_on_exec
);
985 __put_unused_fd(files
, fd
);
986 spin_unlock(&files
->file_lock
);
987 retval
= filp_close(filp
, files
);
989 /* can't restart close syscall because file table entry was cleared */
990 if (unlikely(retval
== -ERESTARTSYS
||
991 retval
== -ERESTARTNOINTR
||
992 retval
== -ERESTARTNOHAND
||
993 retval
== -ERESTART_RESTARTBLOCK
))
999 spin_unlock(&files
->file_lock
);
1002 EXPORT_SYMBOL(sys_close
);
1005 * This routine simulates a hangup on the tty, to arrange that users
1006 * are given clean terminals at login time.
1008 SYSCALL_DEFINE0(vhangup
)
1010 if (capable(CAP_SYS_TTY_CONFIG
)) {
1018 * Called when an inode is about to be open.
1019 * We use this to disallow opening large files on 32bit systems if
1020 * the caller didn't specify O_LARGEFILE. On 64bit systems we force
1021 * on this flag in sys_open.
1023 int generic_file_open(struct inode
* inode
, struct file
* filp
)
1025 if (!(filp
->f_flags
& O_LARGEFILE
) && i_size_read(inode
) > MAX_NON_LFS
)
1030 EXPORT_SYMBOL(generic_file_open
);
1033 * This is used by subsystems that don't want seekable
1034 * file descriptors. The function is not supposed to ever fail, the only
1035 * reason it returns an 'int' and not 'void' is so that it can be plugged
1036 * directly into file_operations structure.
1038 int nonseekable_open(struct inode
*inode
, struct file
*filp
)
1040 filp
->f_mode
&= ~(FMODE_LSEEK
| FMODE_PREAD
| FMODE_PWRITE
);
1044 EXPORT_SYMBOL(nonseekable_open
);