4 * Copyright (C) 1991, 1992 Linus Torvalds
7 #include <linux/string.h>
9 #include <linux/utime.h>
10 #include <linux/file.h>
11 #include <linux/smp_lock.h>
12 #include <linux/quotaops.h>
13 #include <linux/fsnotify.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/tty.h>
17 #include <linux/namei.h>
18 #include <linux/backing-dev.h>
19 #include <linux/capability.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/vs_limit.h>
32 #include <linux/vs_dlimit.h>
33 #include <linux/vserver/xid.h>
35 #include <asm/unistd.h>
37 int vfs_statfs(struct super_block *sb, struct kstatfs *buf)
43 if (sb->s_op->statfs) {
44 memset(buf, 0, sizeof(*buf));
45 retval = security_sb_statfs(sb);
48 retval = sb->s_op->statfs(sb, buf);
49 if (retval == 0 && buf->f_frsize == 0)
50 buf->f_frsize = buf->f_bsize;
52 if (!vx_check(0, VX_ADMIN|VX_WATCH))
53 vx_vsi_statfs(sb, buf);
58 EXPORT_SYMBOL(vfs_statfs);
60 static int vfs_statfs_native(struct super_block *sb, struct statfs *buf)
65 retval = vfs_statfs(sb, &st);
69 if (sizeof(*buf) == sizeof(st))
70 memcpy(buf, &st, sizeof(st));
72 if (sizeof buf->f_blocks == 4) {
73 if ((st.f_blocks | st.f_bfree | st.f_bavail) &
74 0xffffffff00000000ULL)
77 * f_files and f_ffree may be -1; it's okay to stuff
80 if (st.f_files != -1 &&
81 (st.f_files & 0xffffffff00000000ULL))
83 if (st.f_ffree != -1 &&
84 (st.f_ffree & 0xffffffff00000000ULL))
88 buf->f_type = st.f_type;
89 buf->f_bsize = st.f_bsize;
90 buf->f_blocks = st.f_blocks;
91 buf->f_bfree = st.f_bfree;
92 buf->f_bavail = st.f_bavail;
93 buf->f_files = st.f_files;
94 buf->f_ffree = st.f_ffree;
95 buf->f_fsid = st.f_fsid;
96 buf->f_namelen = st.f_namelen;
97 buf->f_frsize = st.f_frsize;
98 memset(buf->f_spare, 0, sizeof(buf->f_spare));
103 static int vfs_statfs64(struct super_block *sb, struct statfs64 *buf)
108 retval = vfs_statfs(sb, &st);
112 if (sizeof(*buf) == sizeof(st))
113 memcpy(buf, &st, sizeof(st));
115 buf->f_type = st.f_type;
116 buf->f_bsize = st.f_bsize;
117 buf->f_blocks = st.f_blocks;
118 buf->f_bfree = st.f_bfree;
119 buf->f_bavail = st.f_bavail;
120 buf->f_files = st.f_files;
121 buf->f_ffree = st.f_ffree;
122 buf->f_fsid = st.f_fsid;
123 buf->f_namelen = st.f_namelen;
124 buf->f_frsize = st.f_frsize;
125 memset(buf->f_spare, 0, sizeof(buf->f_spare));
130 asmlinkage long sys_statfs(const char __user * path, struct statfs __user * buf)
135 error = user_path_walk(path, &nd);
138 error = vfs_statfs_native(nd.dentry->d_inode->i_sb, &tmp);
139 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
147 asmlinkage long sys_statfs64(const char __user *path, size_t sz, struct statfs64 __user *buf)
152 if (sz != sizeof(*buf))
154 error = user_path_walk(path, &nd);
157 error = vfs_statfs64(nd.dentry->d_inode->i_sb, &tmp);
158 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
166 asmlinkage long sys_fstatfs(unsigned int fd, struct statfs __user * buf)
176 error = vfs_statfs_native(file->f_dentry->d_inode->i_sb, &tmp);
177 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
184 asmlinkage long sys_fstatfs64(unsigned int fd, size_t sz, struct statfs64 __user *buf)
190 if (sz != sizeof(*buf))
197 error = vfs_statfs64(file->f_dentry->d_inode->i_sb, &tmp);
198 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
205 int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
209 struct iattr newattrs;
211 /* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */
215 newattrs.ia_size = length;
216 newattrs.ia_valid = ATTR_SIZE | time_attrs;
218 newattrs.ia_file = filp;
219 newattrs.ia_valid |= ATTR_FILE;
222 mutex_lock(&dentry->d_inode->i_mutex);
223 err = notify_change(dentry, &newattrs);
224 mutex_unlock(&dentry->d_inode->i_mutex);
228 static long do_sys_truncate(const char __user * path, loff_t length)
231 struct inode * inode;
235 if (length < 0) /* sorry, but loff_t says... */
238 error = user_path_walk(path, &nd);
241 inode = nd.dentry->d_inode;
243 /* For directories it's -EISDIR, for other non-regulars - -EINVAL */
245 if (S_ISDIR(inode->i_mode))
249 if (!S_ISREG(inode->i_mode))
252 error = vfs_permission(&nd, MAY_WRITE);
257 if (IS_RDONLY(inode) || MNT_IS_RDONLY(nd.mnt))
261 if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
265 * Make sure that there are no leases.
267 error = break_lease(inode, FMODE_WRITE);
271 error = get_write_access(inode);
275 error = locks_verify_truncate(inode, NULL, length);
278 error = do_truncate(nd.dentry, length, 0, NULL);
280 put_write_access(inode);
288 asmlinkage long sys_truncate(const char __user * path, unsigned long length)
290 /* on 32-bit boxen it will cut the range 2^31--2^32-1 off */
291 return do_sys_truncate(path, (long)length);
294 static long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
296 struct inode * inode;
297 struct dentry *dentry;
309 /* explicitly opened as large or we are on 64-bit box */
310 if (file->f_flags & O_LARGEFILE)
313 dentry = file->f_dentry;
314 inode = dentry->d_inode;
316 if (!S_ISREG(inode->i_mode) || !(file->f_mode & FMODE_WRITE))
320 /* Cannot ftruncate over 2^31 bytes without large file support */
321 if (small && length > MAX_NON_LFS)
325 if (IS_APPEND(inode))
328 error = locks_verify_truncate(inode, file, length);
330 error = do_truncate(dentry, length, 0, file);
337 asmlinkage long sys_ftruncate(unsigned int fd, unsigned long length)
339 long ret = do_sys_ftruncate(fd, length, 1);
340 /* avoid REGPARM breakage on x86: */
341 prevent_tail_call(ret);
345 /* LFS versions of truncate are only needed on 32 bit machines */
346 #if BITS_PER_LONG == 32
347 asmlinkage long sys_truncate64(const char __user * path, loff_t length)
349 return do_sys_truncate(path, length);
352 asmlinkage long sys_ftruncate64(unsigned int fd, loff_t length)
354 long ret = do_sys_ftruncate(fd, length, 0);
355 /* avoid REGPARM breakage on x86: */
356 prevent_tail_call(ret);
361 #ifdef __ARCH_WANT_SYS_UTIME
364 * sys_utime() can be implemented in user-level using sys_utimes().
365 * Is this for backwards compatibility? If so, why not move it
366 * into the appropriate arch directory (for those architectures that
370 /* If times==NULL, set access and modification to current time,
371 * must be owner or have write permission.
372 * Else, update from *times, must be owner or super user.
374 asmlinkage long sys_utime(char __user * filename, struct utimbuf __user * times)
378 struct inode * inode;
379 struct iattr newattrs;
381 error = user_path_walk(filename, &nd);
384 inode = nd.dentry->d_inode;
387 if (IS_RDONLY(inode) || MNT_IS_RDONLY(nd.mnt))
390 /* Don't worry, the checks are done in inode_change_ok() */
391 newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
394 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
397 error = get_user(newattrs.ia_atime.tv_sec, ×->actime);
398 newattrs.ia_atime.tv_nsec = 0;
400 error = get_user(newattrs.ia_mtime.tv_sec, ×->modtime);
401 newattrs.ia_mtime.tv_nsec = 0;
405 newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
408 if (IS_IMMUTABLE(inode))
411 if (current->fsuid != inode->i_uid &&
412 (error = vfs_permission(&nd, MAY_WRITE)) != 0)
415 mutex_lock(&inode->i_mutex);
416 error = notify_change(nd.dentry, &newattrs);
417 mutex_unlock(&inode->i_mutex);
426 /* If times==NULL, set access and modification to current time,
427 * must be owner or have write permission.
428 * Else, update from *times, must be owner or super user.
430 long do_utimes(int dfd, char __user *filename, struct timeval *times)
434 struct inode * inode;
435 struct iattr newattrs;
437 error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd);
441 inode = nd.dentry->d_inode;
444 if (IS_RDONLY(inode) || MNT_IS_RDONLY(nd.mnt))
447 /* Don't worry, the checks are done in inode_change_ok() */
448 newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
451 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
454 newattrs.ia_atime.tv_sec = times[0].tv_sec;
455 newattrs.ia_atime.tv_nsec = times[0].tv_usec * 1000;
456 newattrs.ia_mtime.tv_sec = times[1].tv_sec;
457 newattrs.ia_mtime.tv_nsec = times[1].tv_usec * 1000;
458 newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
461 if (IS_IMMUTABLE(inode))
464 if (current->fsuid != inode->i_uid &&
465 (error = vfs_permission(&nd, MAY_WRITE)) != 0)
468 mutex_lock(&inode->i_mutex);
469 error = notify_change(nd.dentry, &newattrs);
470 mutex_unlock(&inode->i_mutex);
477 asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes)
479 struct timeval times[2];
481 if (utimes && copy_from_user(×, utimes, sizeof(times)))
483 return do_utimes(dfd, filename, utimes ? times : NULL);
486 asmlinkage long sys_utimes(char __user *filename, struct timeval __user *utimes)
488 return sys_futimesat(AT_FDCWD, filename, utimes);
493 * access() needs to use the real uid/gid, not the effective uid/gid.
494 * We do this by temporarily clearing all FS-related capabilities and
495 * switching the fsuid/fsgid around to the real ones.
497 asmlinkage long sys_faccessat(int dfd, const char __user *filename, int mode)
500 int old_fsuid, old_fsgid;
501 kernel_cap_t old_cap;
504 if (mode & ~S_IRWXO) /* where's F_OK, X_OK, W_OK, R_OK? */
507 old_fsuid = current->fsuid;
508 old_fsgid = current->fsgid;
509 old_cap = current->cap_effective;
511 current->fsuid = current->uid;
512 current->fsgid = current->gid;
515 * Clear the capabilities if we switch to a non-root user
517 * FIXME: There is a race here against sys_capset. The
518 * capabilities can change yet we will restore the old
519 * value below. We should hold task_capabilities_lock,
520 * but we cannot because user_path_walk can sleep.
523 cap_clear(current->cap_effective);
525 current->cap_effective = current->cap_permitted;
527 res = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW|LOOKUP_ACCESS, &nd);
529 res = vfs_permission(&nd, mode);
530 /* SuS v2 requires we report a read only fs too */
531 if(!res && (mode & S_IWOTH)
532 && (IS_RDONLY(nd.dentry->d_inode) || MNT_IS_RDONLY(nd.mnt))
533 && !special_file(nd.dentry->d_inode->i_mode))
538 current->fsuid = old_fsuid;
539 current->fsgid = old_fsgid;
540 current->cap_effective = old_cap;
545 asmlinkage long sys_access(const char __user *filename, int mode)
547 return sys_faccessat(AT_FDCWD, filename, mode);
550 asmlinkage long sys_chdir(const char __user * filename)
555 error = __user_walk(filename, LOOKUP_FOLLOW|LOOKUP_DIRECTORY, &nd);
559 error = vfs_permission(&nd, MAY_EXEC);
563 set_fs_pwd(current->fs, nd.mnt, nd.dentry);
571 EXPORT_SYMBOL_GPL(sys_chdir);
573 asmlinkage long sys_fchdir(unsigned int fd)
576 struct dentry *dentry;
578 struct vfsmount *mnt;
586 dentry = file->f_dentry;
587 mnt = file->f_vfsmnt;
588 inode = dentry->d_inode;
591 if (!S_ISDIR(inode->i_mode))
594 error = file_permission(file, MAY_EXEC);
596 set_fs_pwd(current->fs, mnt, dentry);
603 asmlinkage long sys_chroot(const char __user * filename)
608 error = __user_walk(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY | LOOKUP_NOALT, &nd);
612 error = vfs_permission(&nd, MAY_EXEC);
617 if (!capable(CAP_SYS_CHROOT))
620 set_fs_root(current->fs, nd.mnt, nd.dentry);
629 EXPORT_SYMBOL_GPL(sys_chroot);
631 asmlinkage long sys_fchmod(unsigned int fd, mode_t mode)
633 struct inode * inode;
634 struct dentry * dentry;
637 struct iattr newattrs;
643 dentry = file->f_dentry;
644 inode = dentry->d_inode;
646 audit_inode(NULL, inode, 0);
649 if (IS_RDONLY(inode) || MNT_IS_RDONLY(file->f_vfsmnt))
652 if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
654 mutex_lock(&inode->i_mutex);
655 if (mode == (mode_t) -1)
656 mode = inode->i_mode;
657 newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
658 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
659 err = notify_change(dentry, &newattrs);
660 mutex_unlock(&inode->i_mutex);
668 asmlinkage long sys_fchmodat(int dfd, const char __user *filename,
672 struct inode * inode;
674 struct iattr newattrs;
676 error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd);
679 inode = nd.dentry->d_inode;
682 if (IS_RDONLY(inode) || MNT_IS_RDONLY(nd.mnt))
686 if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
689 mutex_lock(&inode->i_mutex);
690 if (mode == (mode_t) -1)
691 mode = inode->i_mode;
692 newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
693 newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
694 error = notify_change(nd.dentry, &newattrs);
695 mutex_unlock(&inode->i_mutex);
703 asmlinkage long sys_chmod(const char __user *filename, mode_t mode)
705 return sys_fchmodat(AT_FDCWD, filename, mode);
708 static int chown_common(struct dentry *dentry, struct vfsmount *mnt,
709 uid_t user, gid_t group)
711 struct inode * inode;
713 struct iattr newattrs;
716 if (!(inode = dentry->d_inode)) {
717 printk(KERN_ERR "chown_common: NULL inode\n");
721 if (IS_RDONLY(inode) || MNT_IS_RDONLY(mnt))
724 if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
726 newattrs.ia_valid = ATTR_CTIME;
727 if (user != (uid_t) -1) {
728 newattrs.ia_valid |= ATTR_UID;
729 newattrs.ia_uid = vx_map_uid(user);
731 if (group != (gid_t) -1) {
732 newattrs.ia_valid |= ATTR_GID;
733 newattrs.ia_gid = vx_map_gid(group);
735 if (!S_ISDIR(inode->i_mode))
736 newattrs.ia_valid |= ATTR_KILL_SUID|ATTR_KILL_SGID;
737 mutex_lock(&inode->i_mutex);
738 error = notify_change(dentry, &newattrs);
739 mutex_unlock(&inode->i_mutex);
744 asmlinkage long sys_chown(const char __user * filename, uid_t user, gid_t group)
749 error = user_path_walk(filename, &nd);
751 error = chown_common(nd.dentry, nd.mnt, user, group);
757 asmlinkage long sys_fchownat(int dfd, const char __user *filename, uid_t user,
758 gid_t group, int flag)
764 if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
767 follow = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
768 error = __user_walk_fd(dfd, filename, follow, &nd);
770 error = chown_common(nd.dentry, nd.mnt, user, group);
777 asmlinkage long sys_lchown(const char __user * filename, uid_t user, gid_t group)
782 error = user_path_walk_link(filename, &nd);
784 error = chown_common(nd.dentry, nd.mnt, user, group);
791 asmlinkage long sys_fchown(unsigned int fd, uid_t user, gid_t group)
798 struct dentry * dentry;
799 dentry = file->f_dentry;
800 audit_inode(NULL, dentry->d_inode, 0);
801 error = chown_common(dentry, file->f_vfsmnt, user, group);
807 static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt,
808 int flags, struct file *f,
809 int (*open)(struct inode *, struct file *))
815 f->f_mode = ((flags+1) & O_ACCMODE) | FMODE_LSEEK |
816 FMODE_PREAD | FMODE_PWRITE;
817 inode = dentry->d_inode;
818 if (f->f_mode & FMODE_WRITE) {
819 error = get_write_access(inode);
824 f->f_mapping = inode->i_mapping;
825 f->f_dentry = dentry;
828 f->f_op = fops_get(inode->i_fop);
829 file_move(f, &inode->i_sb->s_files);
831 if (!open && f->f_op)
832 open = f->f_op->open;
834 error = open(inode, f);
839 f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
841 file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
843 /* NB: we're sure to have correct a_ops only after f_op->open */
844 if (f->f_flags & O_DIRECT) {
845 if (!f->f_mapping->a_ops ||
846 ((!f->f_mapping->a_ops->direct_IO) &&
847 (!f->f_mapping->a_ops->get_xip_page))) {
849 f = ERR_PTR(-EINVAL);
857 if (f->f_mode & FMODE_WRITE)
858 put_write_access(inode);
866 return ERR_PTR(error);
870 * Note that while the flag value (low two bits) for sys_open means:
876 * 00 - no permissions needed
877 * 01 - read-permission
878 * 10 - write-permission
880 * for the internal routines (ie open_namei()/follow_link() etc). 00 is
883 static struct file *do_filp_open(int dfd, const char *filename, int flags,
886 int namei_flags, error;
890 if ((namei_flags+1) & O_ACCMODE)
893 error = open_namei(dfd, filename, namei_flags, mode, &nd);
895 return nameidata_to_filp(&nd, flags);
897 return ERR_PTR(error);
900 struct file *filp_open(const char *filename, int flags, int mode)
902 return do_filp_open(AT_FDCWD, filename, flags, mode);
904 EXPORT_SYMBOL(filp_open);
907 * lookup_instantiate_filp - instantiates the open intent filp
908 * @nd: pointer to nameidata
909 * @dentry: pointer to dentry
910 * @open: open callback
912 * Helper for filesystems that want to use lookup open intents and pass back
913 * a fully instantiated struct file to the caller.
914 * This function is meant to be called from within a filesystem's
916 * Beware of calling it for non-regular files! Those ->open methods might block
917 * (e.g. in fifo_open), leaving you with parent locked (and in case of fifo,
918 * leading to a deadlock, as nobody can open that fifo anymore, because
919 * another process to open fifo will block on locked parent when doing lookup).
920 * Note that in case of error, nd->intent.open.file is destroyed, but the
921 * path information remains valid.
922 * If the open callback is set to NULL, then the standard f_op->open()
923 * filesystem callback is substituted.
925 struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
926 int (*open)(struct inode *, struct file *))
928 if (IS_ERR(nd->intent.open.file))
932 nd->intent.open.file = __dentry_open(dget(dentry), mntget(nd->mnt),
933 nd->intent.open.flags - 1,
934 nd->intent.open.file,
937 return nd->intent.open.file;
939 release_open_intent(nd);
940 nd->intent.open.file = (struct file *)dentry;
943 EXPORT_SYMBOL_GPL(lookup_instantiate_filp);
946 * nameidata_to_filp - convert a nameidata to an open filp.
947 * @nd: pointer to nameidata
950 * Note that this function destroys the original nameidata
952 struct file *nameidata_to_filp(struct nameidata *nd, int flags)
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_dentry == NULL)
960 filp = __dentry_open(nd->dentry, nd->mnt, flags, filp, NULL);
967 * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an
970 struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
976 f = get_empty_filp();
980 return ERR_PTR(error);
983 return __dentry_open(dentry, mnt, flags, f, NULL);
985 EXPORT_SYMBOL(dentry_open);
988 * Find an empty file descriptor entry, and mark it busy.
990 int get_unused_fd(void)
992 struct files_struct * files = current->files;
997 spin_lock(&files->file_lock);
1000 fdt = files_fdtable(files);
1001 fd = find_next_zero_bit(fdt->open_fds->fds_bits,
1006 * N.B. For clone tasks sharing a files structure, this test
1007 * will limit the total number of files that can be opened.
1009 if (fd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
1012 /* Do we need to expand the fd array or fd set? */
1013 error = expand_files(files, fd);
1019 * If we needed to expand the fs array we
1020 * might have blocked - try again.
1026 FD_SET(fd, fdt->open_fds);
1027 FD_CLR(fd, fdt->close_on_exec);
1028 files->next_fd = fd + 1;
1032 if (fdt->fd[fd] != NULL) {
1033 printk(KERN_WARNING "get_unused_fd: slot %d not NULL!\n", fd);
1040 spin_unlock(&files->file_lock);
1044 EXPORT_SYMBOL(get_unused_fd);
1046 static void __put_unused_fd(struct files_struct *files, unsigned int fd)
1048 struct fdtable *fdt = files_fdtable(files);
1049 __FD_CLR(fd, fdt->open_fds);
1050 if (fd < files->next_fd)
1051 files->next_fd = fd;
1055 void fastcall put_unused_fd(unsigned int fd)
1057 struct files_struct *files = current->files;
1058 spin_lock(&files->file_lock);
1059 __put_unused_fd(files, fd);
1060 spin_unlock(&files->file_lock);
1063 EXPORT_SYMBOL(put_unused_fd);
1066 * Install a file pointer in the fd array.
1068 * The VFS is full of places where we drop the files lock between
1069 * setting the open_fds bitmap and installing the file in the file
1070 * array. At any such point, we are vulnerable to a dup2() race
1071 * installing a file in the array before us. We need to detect this and
1072 * fput() the struct file we are about to overwrite in this case.
1074 * It should never happen - if we allow dup2() do it, _really_ bad things
1078 void fastcall fd_install(unsigned int fd, struct file * file)
1080 struct files_struct *files = current->files;
1081 struct fdtable *fdt;
1082 spin_lock(&files->file_lock);
1083 fdt = files_fdtable(files);
1084 BUG_ON(fdt->fd[fd] != NULL);
1085 rcu_assign_pointer(fdt->fd[fd], file);
1086 spin_unlock(&files->file_lock);
1089 EXPORT_SYMBOL(fd_install);
1091 long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
1093 char *tmp = getname(filename);
1094 int fd = PTR_ERR(tmp);
1097 fd = get_unused_fd();
1099 struct file *f = do_filp_open(dfd, tmp, flags, mode);
1104 fsnotify_open(f->f_dentry);
1113 asmlinkage long sys_open(const char __user *filename, int flags, int mode)
1117 if (force_o_largefile())
1118 flags |= O_LARGEFILE;
1120 ret = do_sys_open(AT_FDCWD, filename, flags, mode);
1121 /* avoid REGPARM breakage on x86: */
1122 prevent_tail_call(ret);
1126 asmlinkage long sys_openat(int dfd, const char __user *filename, int flags,
1131 if (force_o_largefile())
1132 flags |= O_LARGEFILE;
1134 ret = do_sys_open(dfd, filename, flags, mode);
1135 /* avoid REGPARM breakage on x86: */
1136 prevent_tail_call(ret);
1143 * For backward compatibility? Maybe this should be moved
1144 * into arch/i386 instead?
1146 asmlinkage long sys_creat(const char __user * pathname, int mode)
1148 return sys_open(pathname, O_CREAT | O_WRONLY | O_TRUNC, mode);
1154 * "id" is the POSIX thread ID. We use the
1155 * files pointer for this..
1157 int filp_close(struct file *filp, fl_owner_t id)
1161 if (!file_count(filp)) {
1162 printk(KERN_ERR "VFS: Close: file count is 0\n");
1166 if (filp->f_op && filp->f_op->flush)
1167 retval = filp->f_op->flush(filp);
1169 dnotify_flush(filp, id);
1170 locks_remove_posix(filp, id);
1175 EXPORT_SYMBOL(filp_close);
1178 * Careful here! We test whether the file pointer is NULL before
1179 * releasing the fd. This ensures that one clone task can't release
1180 * an fd while another clone is opening it.
1182 asmlinkage long sys_close(unsigned int fd)
1185 struct files_struct *files = current->files;
1186 struct fdtable *fdt;
1188 spin_lock(&files->file_lock);
1189 fdt = files_fdtable(files);
1190 if (fd >= fdt->max_fds)
1195 rcu_assign_pointer(fdt->fd[fd], NULL);
1196 FD_CLR(fd, fdt->close_on_exec);
1197 __put_unused_fd(files, fd);
1198 spin_unlock(&files->file_lock);
1199 return filp_close(filp, files);
1202 spin_unlock(&files->file_lock);
1206 EXPORT_SYMBOL(sys_close);
1209 * This routine simulates a hangup on the tty, to arrange that users
1210 * are given clean terminals at login time.
1212 asmlinkage long sys_vhangup(void)
1214 if (capable(CAP_SYS_TTY_CONFIG)) {
1215 tty_vhangup(current->signal->tty);
1222 * Called when an inode is about to be open.
1223 * We use this to disallow opening large files on 32bit systems if
1224 * the caller didn't specify O_LARGEFILE. On 64bit systems we force
1225 * on this flag in sys_open.
1227 int generic_file_open(struct inode * inode, struct file * filp)
1229 if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
1234 EXPORT_SYMBOL(generic_file_open);
1237 * This is used by subsystems that don't want seekable
1240 int nonseekable_open(struct inode *inode, struct file *filp)
1242 filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE);
1246 EXPORT_SYMBOL(nonseekable_open);