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/quotaops.h>
12 #include <linux/fsnotify.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/tty.h>
16 #include <linux/namei.h>
17 #include <linux/backing-dev.h>
18 #include <linux/capability.h>
19 #include <linux/securebits.h>
20 #include <linux/security.h>
21 #include <linux/mount.h>
22 #include <linux/vfs.h>
23 #include <linux/fcntl.h>
24 #include <asm/uaccess.h>
26 #include <linux/personality.h>
27 #include <linux/pagemap.h>
28 #include <linux/syscalls.h>
29 #include <linux/rcupdate.h>
30 #include <linux/audit.h>
31 #include <linux/falloc.h>
32 #include <linux/fs_struct.h>
34 int vfs_statfs(struct dentry *dentry, struct kstatfs *buf)
40 if (dentry->d_sb->s_op->statfs) {
41 memset(buf, 0, sizeof(*buf));
42 retval = security_sb_statfs(dentry);
45 retval = dentry->d_sb->s_op->statfs(dentry, buf);
46 if (retval == 0 && buf->f_frsize == 0)
47 buf->f_frsize = buf->f_bsize;
53 EXPORT_SYMBOL(vfs_statfs);
55 static int vfs_statfs_native(struct dentry *dentry, struct statfs *buf)
60 retval = vfs_statfs(dentry, &st);
64 if (sizeof(*buf) == sizeof(st))
65 memcpy(buf, &st, sizeof(st));
67 if (sizeof buf->f_blocks == 4) {
68 if ((st.f_blocks | st.f_bfree | st.f_bavail |
69 st.f_bsize | st.f_frsize) &
70 0xffffffff00000000ULL)
73 * f_files and f_ffree may be -1; it's okay to stuff
76 if (st.f_files != -1 &&
77 (st.f_files & 0xffffffff00000000ULL))
79 if (st.f_ffree != -1 &&
80 (st.f_ffree & 0xffffffff00000000ULL))
84 buf->f_type = st.f_type;
85 buf->f_bsize = st.f_bsize;
86 buf->f_blocks = st.f_blocks;
87 buf->f_bfree = st.f_bfree;
88 buf->f_bavail = st.f_bavail;
89 buf->f_files = st.f_files;
90 buf->f_ffree = st.f_ffree;
91 buf->f_fsid = st.f_fsid;
92 buf->f_namelen = st.f_namelen;
93 buf->f_frsize = st.f_frsize;
94 memset(buf->f_spare, 0, sizeof(buf->f_spare));
99 static int vfs_statfs64(struct dentry *dentry, struct statfs64 *buf)
104 retval = vfs_statfs(dentry, &st);
108 if (sizeof(*buf) == sizeof(st))
109 memcpy(buf, &st, sizeof(st));
111 buf->f_type = st.f_type;
112 buf->f_bsize = st.f_bsize;
113 buf->f_blocks = st.f_blocks;
114 buf->f_bfree = st.f_bfree;
115 buf->f_bavail = st.f_bavail;
116 buf->f_files = st.f_files;
117 buf->f_ffree = st.f_ffree;
118 buf->f_fsid = st.f_fsid;
119 buf->f_namelen = st.f_namelen;
120 buf->f_frsize = st.f_frsize;
121 memset(buf->f_spare, 0, sizeof(buf->f_spare));
126 SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf)
131 error = user_path(pathname, &path);
134 error = vfs_statfs_native(path.dentry, &tmp);
135 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
142 SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf)
147 if (sz != sizeof(*buf))
149 error = user_path(pathname, &path);
152 error = vfs_statfs64(path.dentry, &tmp);
153 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
160 SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)
170 error = vfs_statfs_native(file->f_path.dentry, &tmp);
171 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
178 SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)
184 if (sz != sizeof(*buf))
191 error = vfs_statfs64(file->f_path.dentry, &tmp);
192 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
199 int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
203 struct iattr newattrs;
205 /* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */
209 newattrs.ia_size = length;
210 newattrs.ia_valid = ATTR_SIZE | time_attrs;
212 newattrs.ia_file = filp;
213 newattrs.ia_valid |= ATTR_FILE;
216 /* Remove suid/sgid on truncate too */
217 ret = should_remove_suid(dentry);
219 newattrs.ia_valid |= ret | ATTR_FORCE;
221 mutex_lock(&dentry->d_inode->i_mutex);
222 ret = notify_change(dentry, &newattrs);
223 mutex_unlock(&dentry->d_inode->i_mutex);
227 static long do_sys_truncate(const char __user *pathname, loff_t length)
234 if (length < 0) /* sorry, but loff_t says... */
237 error = user_path(pathname, &path);
240 inode = path.dentry->d_inode;
242 /* For directories it's -EISDIR, for other non-regulars - -EINVAL */
244 if (S_ISDIR(inode->i_mode))
248 if (!S_ISREG(inode->i_mode))
251 error = mnt_want_write(path.mnt);
255 error = inode_permission(inode, MAY_WRITE);
257 goto mnt_drop_write_and_out;
260 if (IS_APPEND(inode))
261 goto mnt_drop_write_and_out;
263 error = get_write_access(inode);
265 goto mnt_drop_write_and_out;
268 * Make sure that there are no leases. get_write_access() protects
269 * against the truncate racing with a lease-granting setlease().
271 error = break_lease(inode, FMODE_WRITE);
273 goto put_write_and_out;
275 error = locks_verify_truncate(inode, NULL, length);
277 error = security_path_truncate(&path, length, 0);
280 error = do_truncate(path.dentry, length, 0, NULL);
284 put_write_access(inode);
285 mnt_drop_write_and_out:
286 mnt_drop_write(path.mnt);
293 SYSCALL_DEFINE2(truncate, const char __user *, path, long, length)
295 return do_sys_truncate(path, length);
298 static long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
300 struct inode * inode;
301 struct dentry *dentry;
313 /* explicitly opened as large or we are on 64-bit box */
314 if (file->f_flags & O_LARGEFILE)
317 dentry = file->f_path.dentry;
318 inode = dentry->d_inode;
320 if (!S_ISREG(inode->i_mode) || !(file->f_mode & FMODE_WRITE))
324 /* Cannot ftruncate over 2^31 bytes without large file support */
325 if (small && length > MAX_NON_LFS)
329 if (IS_APPEND(inode))
332 error = locks_verify_truncate(inode, file, length);
334 error = security_path_truncate(&file->f_path, length,
335 ATTR_MTIME|ATTR_CTIME);
337 error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, file);
344 SYSCALL_DEFINE2(ftruncate, unsigned int, fd, unsigned long, length)
346 long ret = do_sys_ftruncate(fd, length, 1);
347 /* avoid REGPARM breakage on x86: */
348 asmlinkage_protect(2, ret, fd, length);
352 /* LFS versions of truncate are only needed on 32 bit machines */
353 #if BITS_PER_LONG == 32
354 SYSCALL_DEFINE(truncate64)(const char __user * path, loff_t length)
356 return do_sys_truncate(path, length);
358 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
359 asmlinkage long SyS_truncate64(long path, loff_t length)
361 return SYSC_truncate64((const char __user *) path, length);
363 SYSCALL_ALIAS(sys_truncate64, SyS_truncate64);
366 SYSCALL_DEFINE(ftruncate64)(unsigned int fd, loff_t length)
368 long ret = do_sys_ftruncate(fd, length, 0);
369 /* avoid REGPARM breakage on x86: */
370 asmlinkage_protect(2, ret, fd, length);
373 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
374 asmlinkage long SyS_ftruncate64(long fd, loff_t length)
376 return SYSC_ftruncate64((unsigned int) fd, length);
378 SYSCALL_ALIAS(sys_ftruncate64, SyS_ftruncate64);
380 #endif /* BITS_PER_LONG == 32 */
383 int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
385 struct inode *inode = file->f_path.dentry->d_inode;
388 if (offset < 0 || len <= 0)
391 /* Return error if mode is not supported */
392 if (mode && !(mode & FALLOC_FL_KEEP_SIZE))
395 if (!(file->f_mode & FMODE_WRITE))
398 * Revalidate the write permissions, in case security policy has
399 * changed since the files were opened.
401 ret = security_file_permission(file, MAY_WRITE);
405 if (S_ISFIFO(inode->i_mode))
409 * Let individual file system decide if it supports preallocation
410 * for directories or not.
412 if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
415 /* Check for wrap through zero too */
416 if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0))
419 if (!inode->i_op->fallocate)
422 return inode->i_op->fallocate(inode, mode, offset, len);
425 SYSCALL_DEFINE(fallocate)(int fd, int mode, loff_t offset, loff_t len)
432 error = do_fallocate(file, mode, offset, len);
439 #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
440 asmlinkage long SyS_fallocate(long fd, long mode, loff_t offset, loff_t len)
442 return SYSC_fallocate((int)fd, (int)mode, offset, len);
444 SYSCALL_ALIAS(sys_fallocate, SyS_fallocate);
448 * access() needs to use the real uid/gid, not the effective uid/gid.
449 * We do this by temporarily clearing all FS-related capabilities and
450 * switching the fsuid/fsgid around to the real ones.
452 SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode)
454 const struct cred *old_cred;
455 struct cred *override_cred;
460 if (mode & ~S_IRWXO) /* where's F_OK, X_OK, W_OK, R_OK? */
463 override_cred = prepare_creds();
467 override_cred->fsuid = override_cred->uid;
468 override_cred->fsgid = override_cred->gid;
470 if (!issecure(SECURE_NO_SETUID_FIXUP)) {
471 /* Clear the capabilities if we switch to a non-root user */
472 if (override_cred->uid)
473 cap_clear(override_cred->cap_effective);
475 override_cred->cap_effective =
476 override_cred->cap_permitted;
479 old_cred = override_creds(override_cred);
481 res = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path);
485 inode = path.dentry->d_inode;
487 if ((mode & MAY_EXEC) && S_ISREG(inode->i_mode)) {
489 * MAY_EXEC on regular files is denied if the fs is mounted
490 * with the "noexec" flag.
493 if (path.mnt->mnt_flags & MNT_NOEXEC)
494 goto out_path_release;
497 res = inode_permission(inode, mode | MAY_ACCESS);
498 /* SuS v2 requires we report a read only fs too */
499 if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
500 goto out_path_release;
502 * This is a rare case where using __mnt_is_readonly()
503 * is OK without a mnt_want/drop_write() pair. Since
504 * no actual write to the fs is performed here, we do
505 * not need to telegraph to that to anyone.
507 * By doing this, we accept that this access is
508 * inherently racy and know that the fs may change
509 * state before we even see this result.
511 if (__mnt_is_readonly(path.mnt))
517 revert_creds(old_cred);
518 put_cred(override_cred);
522 SYSCALL_DEFINE2(access, const char __user *, filename, int, mode)
524 return sys_faccessat(AT_FDCWD, filename, mode);
527 SYSCALL_DEFINE1(chdir, const char __user *, filename)
532 error = user_path_dir(filename, &path);
536 error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_ACCESS);
540 set_fs_pwd(current->fs, &path);
548 SYSCALL_DEFINE1(fchdir, unsigned int, fd)
559 inode = file->f_path.dentry->d_inode;
562 if (!S_ISDIR(inode->i_mode))
565 error = inode_permission(inode, MAY_EXEC | MAY_ACCESS);
567 set_fs_pwd(current->fs, &file->f_path);
574 SYSCALL_DEFINE1(chroot, const char __user *, filename)
579 error = user_path_dir(filename, &path);
583 error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_ACCESS);
588 if (!capable(CAP_SYS_CHROOT))
591 set_fs_root(current->fs, &path);
599 SYSCALL_DEFINE2(fchmod, unsigned int, fd, mode_t, mode)
601 struct inode * inode;
602 struct dentry * dentry;
605 struct iattr newattrs;
611 dentry = file->f_path.dentry;
612 inode = dentry->d_inode;
614 audit_inode(NULL, dentry);
616 err = mnt_want_write_file(file);
619 err = security_path_chmod(dentry, file->f_vfsmnt, mode);
622 mutex_lock(&inode->i_mutex);
623 if (mode == (mode_t) -1)
624 mode = inode->i_mode;
625 newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
626 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
627 err = notify_change(dentry, &newattrs);
628 mutex_unlock(&inode->i_mutex);
630 mnt_drop_write(file->f_path.mnt);
637 SYSCALL_DEFINE3(fchmodat, int, dfd, const char __user *, filename, mode_t, mode)
642 struct iattr newattrs;
644 error = user_path_at(dfd, filename, LOOKUP_FOLLOW, &path);
647 inode = path.dentry->d_inode;
649 error = mnt_want_write(path.mnt);
652 error = security_path_chmod(path.dentry, path.mnt, mode);
655 mutex_lock(&inode->i_mutex);
656 if (mode == (mode_t) -1)
657 mode = inode->i_mode;
658 newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
659 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
660 error = notify_change(path.dentry, &newattrs);
661 mutex_unlock(&inode->i_mutex);
663 mnt_drop_write(path.mnt);
670 SYSCALL_DEFINE2(chmod, const char __user *, filename, mode_t, mode)
672 return sys_fchmodat(AT_FDCWD, filename, mode);
675 static int chown_common(struct dentry * dentry, uid_t user, gid_t group)
677 struct inode *inode = dentry->d_inode;
679 struct iattr newattrs;
681 newattrs.ia_valid = ATTR_CTIME;
682 if (user != (uid_t) -1) {
683 newattrs.ia_valid |= ATTR_UID;
684 newattrs.ia_uid = user;
686 if (group != (gid_t) -1) {
687 newattrs.ia_valid |= ATTR_GID;
688 newattrs.ia_gid = group;
690 if (!S_ISDIR(inode->i_mode))
692 ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
693 mutex_lock(&inode->i_mutex);
694 error = notify_change(dentry, &newattrs);
695 mutex_unlock(&inode->i_mutex);
700 SYSCALL_DEFINE3(chown, const char __user *, filename, uid_t, user, gid_t, group)
705 error = user_path(filename, &path);
708 error = mnt_want_write(path.mnt);
711 error = security_path_chown(&path, user, group);
713 error = chown_common(path.dentry, user, group);
714 mnt_drop_write(path.mnt);
721 SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user,
722 gid_t, group, int, flag)
728 if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
731 follow = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
732 error = user_path_at(dfd, filename, follow, &path);
735 error = mnt_want_write(path.mnt);
738 error = security_path_chown(&path, user, group);
740 error = chown_common(path.dentry, user, group);
741 mnt_drop_write(path.mnt);
748 SYSCALL_DEFINE3(lchown, const char __user *, filename, uid_t, user, gid_t, group)
753 error = user_lpath(filename, &path);
756 error = mnt_want_write(path.mnt);
759 error = security_path_chown(&path, user, group);
761 error = chown_common(path.dentry, user, group);
762 mnt_drop_write(path.mnt);
769 SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group)
773 struct dentry * dentry;
779 error = mnt_want_write_file(file);
782 dentry = file->f_path.dentry;
783 audit_inode(NULL, dentry);
784 error = security_path_chown(&file->f_path, user, group);
786 error = chown_common(dentry, user, group);
787 mnt_drop_write(file->f_path.mnt);
795 * You have to be very careful that these write
796 * counts get cleaned up in error cases and
797 * upon __fput(). This should probably never
798 * be called outside of __dentry_open().
800 static inline int __get_file_write_access(struct inode *inode,
801 struct vfsmount *mnt)
804 error = get_write_access(inode);
808 * Do not take mount writer counts on
809 * special files since no writes to
810 * the mount itself will occur.
812 if (!special_file(inode->i_mode)) {
814 * Balanced in __fput()
816 error = mnt_want_write(mnt);
818 put_write_access(inode);
823 static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
824 int flags, struct file *f,
825 int (*open)(struct inode *, struct file *),
826 const struct cred *cred)
832 f->f_mode = (__force fmode_t)((flags+1) & O_ACCMODE) | FMODE_LSEEK |
833 FMODE_PREAD | FMODE_PWRITE;
834 inode = dentry->d_inode;
835 if (f->f_mode & FMODE_WRITE) {
836 error = __get_file_write_access(inode, mnt);
839 if (!special_file(inode->i_mode))
843 f->f_mapping = inode->i_mapping;
844 f->f_path.dentry = dentry;
847 f->f_op = fops_get(inode->i_fop);
848 file_move(f, &inode->i_sb->s_files);
850 error = security_dentry_open(f, cred);
854 if (!open && f->f_op)
855 open = f->f_op->open;
857 error = open(inode, f);
862 f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
864 file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
866 /* NB: we're sure to have correct a_ops only after f_op->open */
867 if (f->f_flags & O_DIRECT) {
868 if (!f->f_mapping->a_ops ||
869 ((!f->f_mapping->a_ops->direct_IO) &&
870 (!f->f_mapping->a_ops->get_xip_mem))) {
872 f = ERR_PTR(-EINVAL);
880 if (f->f_mode & FMODE_WRITE) {
881 put_write_access(inode);
882 if (!special_file(inode->i_mode)) {
884 * We don't consider this a real
885 * mnt_want/drop_write() pair
886 * because it all happenend right
887 * here, so just reset the state.
894 f->f_path.dentry = NULL;
895 f->f_path.mnt = NULL;
900 return ERR_PTR(error);
904 * lookup_instantiate_filp - instantiates the open intent filp
905 * @nd: pointer to nameidata
906 * @dentry: pointer to dentry
907 * @open: open callback
909 * Helper for filesystems that want to use lookup open intents and pass back
910 * a fully instantiated struct file to the caller.
911 * This function is meant to be called from within a filesystem's
913 * Beware of calling it for non-regular files! Those ->open methods might block
914 * (e.g. in fifo_open), leaving you with parent locked (and in case of fifo,
915 * leading to a deadlock, as nobody can open that fifo anymore, because
916 * another process to open fifo will block on locked parent when doing lookup).
917 * Note that in case of error, nd->intent.open.file is destroyed, but the
918 * path information remains valid.
919 * If the open callback is set to NULL, then the standard f_op->open()
920 * filesystem callback is substituted.
922 struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
923 int (*open)(struct inode *, struct file *))
925 const struct cred *cred = current_cred();
927 if (IS_ERR(nd->intent.open.file))
931 nd->intent.open.file = __dentry_open(dget(dentry), mntget(nd->path.mnt),
932 nd->intent.open.flags - 1,
933 nd->intent.open.file,
936 return nd->intent.open.file;
938 release_open_intent(nd);
939 nd->intent.open.file = (struct file *)dentry;
942 EXPORT_SYMBOL_GPL(lookup_instantiate_filp);
945 * nameidata_to_filp - convert a nameidata to an open filp.
946 * @nd: pointer to nameidata
949 * Note that this function destroys the original nameidata
951 struct file *nameidata_to_filp(struct nameidata *nd, int flags)
953 const struct cred *cred = current_cred();
956 /* Pick up the filp from the open intent */
957 filp = nd->intent.open.file;
958 /* Has the filesystem initialised the file for us? */
959 if (filp->f_path.dentry == NULL)
960 filp = __dentry_open(nd->path.dentry, nd->path.mnt, flags, filp,
968 * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an
971 struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags,
972 const struct cred *cred)
977 validate_creds(cred);
980 * We must always pass in a valid mount pointer. Historically
981 * callers got away with not passing it, but we must enforce this at
982 * the earliest possible point now to avoid strange problems deep in the
986 printk(KERN_WARNING "%s called with NULL vfsmount\n", __func__);
988 return ERR_PTR(-EINVAL);
992 f = get_empty_filp();
996 return ERR_PTR(error);
999 return __dentry_open(dentry, mnt, flags, f, NULL, cred);
1001 EXPORT_SYMBOL(dentry_open);
1003 static void __put_unused_fd(struct files_struct *files, unsigned int fd)
1005 struct fdtable *fdt = files_fdtable(files);
1006 __FD_CLR(fd, fdt->open_fds);
1007 if (fd < files->next_fd)
1008 files->next_fd = fd;
1011 void put_unused_fd(unsigned int fd)
1013 struct files_struct *files = current->files;
1014 spin_lock(&files->file_lock);
1015 __put_unused_fd(files, fd);
1016 spin_unlock(&files->file_lock);
1019 EXPORT_SYMBOL(put_unused_fd);
1022 * Install a file pointer in the fd array.
1024 * The VFS is full of places where we drop the files lock between
1025 * setting the open_fds bitmap and installing the file in the file
1026 * array. At any such point, we are vulnerable to a dup2() race
1027 * installing a file in the array before us. We need to detect this and
1028 * fput() the struct file we are about to overwrite in this case.
1030 * It should never happen - if we allow dup2() do it, _really_ bad things
1034 void fd_install(unsigned int fd, struct file *file)
1036 struct files_struct *files = current->files;
1037 struct fdtable *fdt;
1038 spin_lock(&files->file_lock);
1039 fdt = files_fdtable(files);
1040 BUG_ON(fdt->fd[fd] != NULL);
1041 rcu_assign_pointer(fdt->fd[fd], file);
1042 spin_unlock(&files->file_lock);
1045 EXPORT_SYMBOL(fd_install);
1047 long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
1049 char *tmp = getname(filename);
1050 int fd = PTR_ERR(tmp);
1053 fd = get_unused_fd_flags(flags);
1055 struct file *f = do_filp_open(dfd, tmp, flags, mode, 0);
1060 fsnotify_open(f->f_path.dentry);
1069 SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, int, mode)
1073 if (force_o_largefile())
1074 flags |= O_LARGEFILE;
1076 ret = do_sys_open(AT_FDCWD, filename, flags, mode);
1077 /* avoid REGPARM breakage on x86: */
1078 asmlinkage_protect(3, ret, filename, flags, mode);
1082 SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags,
1087 if (force_o_largefile())
1088 flags |= O_LARGEFILE;
1090 ret = do_sys_open(dfd, filename, flags, mode);
1091 /* avoid REGPARM breakage on x86: */
1092 asmlinkage_protect(4, ret, dfd, filename, flags, mode);
1099 * For backward compatibility? Maybe this should be moved
1100 * into arch/i386 instead?
1102 SYSCALL_DEFINE2(creat, const char __user *, pathname, int, mode)
1104 return sys_open(pathname, O_CREAT | O_WRONLY | O_TRUNC, mode);
1110 * "id" is the POSIX thread ID. We use the
1111 * files pointer for this..
1113 int filp_close(struct file *filp, fl_owner_t id)
1117 if (!file_count(filp)) {
1118 printk(KERN_ERR "VFS: Close: file count is 0\n");
1122 if (filp->f_op && filp->f_op->flush)
1123 retval = filp->f_op->flush(filp, id);
1125 dnotify_flush(filp, id);
1126 locks_remove_posix(filp, id);
1131 EXPORT_SYMBOL(filp_close);
1134 * Careful here! We test whether the file pointer is NULL before
1135 * releasing the fd. This ensures that one clone task can't release
1136 * an fd while another clone is opening it.
1138 SYSCALL_DEFINE1(close, unsigned int, fd)
1141 struct files_struct *files = current->files;
1142 struct fdtable *fdt;
1145 spin_lock(&files->file_lock);
1146 fdt = files_fdtable(files);
1147 if (fd >= fdt->max_fds)
1152 rcu_assign_pointer(fdt->fd[fd], NULL);
1153 FD_CLR(fd, fdt->close_on_exec);
1154 __put_unused_fd(files, fd);
1155 spin_unlock(&files->file_lock);
1156 retval = filp_close(filp, files);
1158 /* can't restart close syscall because file table entry was cleared */
1159 if (unlikely(retval == -ERESTARTSYS ||
1160 retval == -ERESTARTNOINTR ||
1161 retval == -ERESTARTNOHAND ||
1162 retval == -ERESTART_RESTARTBLOCK))
1168 spin_unlock(&files->file_lock);
1171 EXPORT_SYMBOL(sys_close);
1174 * This routine simulates a hangup on the tty, to arrange that users
1175 * are given clean terminals at login time.
1177 SYSCALL_DEFINE0(vhangup)
1179 if (capable(CAP_SYS_TTY_CONFIG)) {
1187 * Called when an inode is about to be open.
1188 * We use this to disallow opening large files on 32bit systems if
1189 * the caller didn't specify O_LARGEFILE. On 64bit systems we force
1190 * on this flag in sys_open.
1192 int generic_file_open(struct inode * inode, struct file * filp)
1194 if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
1199 EXPORT_SYMBOL(generic_file_open);
1202 * This is used by subsystems that don't want seekable
1205 int nonseekable_open(struct inode *inode, struct file *filp)
1207 filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE);
1211 EXPORT_SYMBOL(nonseekable_open);