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freebsd-skq/sys/fs/ext2fs/ext2_vnops.c
Pedro F. Giffuni 70097aac13 Define ext2fs local types and use them. 
Add definitions for e2fs_daddr_t, e4fs_daddr_t in addition
to the already existing e2fs_lbn_t and adjust them for ext4.
Other than making the code more readable these changes should
fix problems related to big filesystems.

Setting the proper types can be tricky so the process was
helped by looking at UFS. In our implementation, logical block
numbers can be negative and the code depends on it. In ext2,
block numbers are unsigned so it is convenient to keep
e2fs_daddr_t unsigned and use the complete 32 bits. In the
case of e4fs_daddr_t, while the value should be unsigned, for
ext4 we only need to support 48 bits so preserving an extra
bit from the sign is not an issue.

While here also drop the ext2_setblock() prototype that was
never used.

Discussed with:	mckusick, bde
MFC after:	3 weeks
2013-08-13 15:40:43 +00:00

2066 lines
51 KiB
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/*-
* modified for EXT2FS support in Lites 1.1
*
* Aug 1995, Godmar Back (gback@cs.utah.edu)
* University of Utah, Department of Computer Science
*/
/*-
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ufs_vnops.c 8.7 (Berkeley) 2/3/94
* @(#)ufs_vnops.c 8.27 (Berkeley) 5/27/95
* $FreeBSD$
*/
#include "opt_suiddir.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/filio.h>
#include <sys/stat.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/endian.h>
#include <sys/priv.h>
#include <sys/mount.h>
#include <sys/unistd.h>
#include <sys/time.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/lockf.h>
#include <sys/event.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <vm/vnode_pager.h>
#include "opt_directio.h"
#include <ufs/ufs/dir.h>
#include <fs/ext2fs/fs.h>
#include <fs/ext2fs/inode.h>
#include <fs/ext2fs/ext2_extern.h>
#include <fs/ext2fs/ext2fs.h>
#include <fs/ext2fs/ext2_dinode.h>
#include <fs/ext2fs/ext2_dir.h>
#include <fs/ext2fs/ext2_mount.h>
static int ext2_makeinode(int mode, struct vnode *, struct vnode **, struct componentname *);
static void ext2_itimes_locked(struct vnode *);
static int ext4_ext_read(struct vop_read_args *);
static int ext2_ind_read(struct vop_read_args *);
static vop_access_t ext2_access;
static int ext2_chmod(struct vnode *, int, struct ucred *, struct thread *);
static int ext2_chown(struct vnode *, uid_t, gid_t, struct ucred *,
struct thread *);
static vop_close_t ext2_close;
static vop_create_t ext2_create;
static vop_fsync_t ext2_fsync;
static vop_getattr_t ext2_getattr;
static vop_ioctl_t ext2_ioctl;
static vop_link_t ext2_link;
static vop_mkdir_t ext2_mkdir;
static vop_mknod_t ext2_mknod;
static vop_open_t ext2_open;
static vop_pathconf_t ext2_pathconf;
static vop_print_t ext2_print;
static vop_read_t ext2_read;
static vop_readlink_t ext2_readlink;
static vop_remove_t ext2_remove;
static vop_rename_t ext2_rename;
static vop_rmdir_t ext2_rmdir;
static vop_setattr_t ext2_setattr;
static vop_strategy_t ext2_strategy;
static vop_symlink_t ext2_symlink;
static vop_write_t ext2_write;
static vop_vptofh_t ext2_vptofh;
static vop_close_t ext2fifo_close;
static vop_kqfilter_t ext2fifo_kqfilter;
/* Global vfs data structures for ext2. */
struct vop_vector ext2_vnodeops = {
.vop_default = &default_vnodeops,
.vop_access = ext2_access,
.vop_bmap = ext2_bmap,
.vop_cachedlookup = ext2_lookup,
.vop_close = ext2_close,
.vop_create = ext2_create,
.vop_fsync = ext2_fsync,
.vop_getattr = ext2_getattr,
.vop_inactive = ext2_inactive,
.vop_ioctl = ext2_ioctl,
.vop_link = ext2_link,
.vop_lookup = vfs_cache_lookup,
.vop_mkdir = ext2_mkdir,
.vop_mknod = ext2_mknod,
.vop_open = ext2_open,
.vop_pathconf = ext2_pathconf,
.vop_poll = vop_stdpoll,
.vop_print = ext2_print,
.vop_read = ext2_read,
.vop_readdir = ext2_readdir,
.vop_readlink = ext2_readlink,
.vop_reallocblks = ext2_reallocblks,
.vop_reclaim = ext2_reclaim,
.vop_remove = ext2_remove,
.vop_rename = ext2_rename,
.vop_rmdir = ext2_rmdir,
.vop_setattr = ext2_setattr,
.vop_strategy = ext2_strategy,
.vop_symlink = ext2_symlink,
.vop_write = ext2_write,
.vop_vptofh = ext2_vptofh,
};
struct vop_vector ext2_fifoops = {
.vop_default = &fifo_specops,
.vop_access = ext2_access,
.vop_close = ext2fifo_close,
.vop_fsync = ext2_fsync,
.vop_getattr = ext2_getattr,
.vop_inactive = ext2_inactive,
.vop_kqfilter = ext2fifo_kqfilter,
.vop_print = ext2_print,
.vop_read = VOP_PANIC,
.vop_reclaim = ext2_reclaim,
.vop_setattr = ext2_setattr,
.vop_write = VOP_PANIC,
.vop_vptofh = ext2_vptofh,
};
/*
* A virgin directory (no blushing please).
* Note that the type and namlen fields are reversed relative to ext2.
* Also, we don't use `struct odirtemplate', since it would just cause
* endianness problems.
*/
static struct dirtemplate mastertemplate = {
0, 12, 1, EXT2_FT_DIR, ".",
0, DIRBLKSIZ - 12, 2, EXT2_FT_DIR, ".."
};
static struct dirtemplate omastertemplate = {
0, 12, 1, EXT2_FT_UNKNOWN, ".",
0, DIRBLKSIZ - 12, 2, EXT2_FT_UNKNOWN, ".."
};
static void
ext2_itimes_locked(struct vnode *vp)
{
struct inode *ip;
struct timespec ts;
ASSERT_VI_LOCKED(vp, __func__);
ip = VTOI(vp);
if ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_UPDATE)) == 0)
return;
if ((vp->v_type == VBLK || vp->v_type == VCHR))
ip->i_flag |= IN_LAZYMOD;
else
ip->i_flag |= IN_MODIFIED;
if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
vfs_timestamp(&ts);
if (ip->i_flag & IN_ACCESS) {
ip->i_atime = ts.tv_sec;
ip->i_atimensec = ts.tv_nsec;
}
if (ip->i_flag & IN_UPDATE) {
ip->i_mtime = ts.tv_sec;
ip->i_mtimensec = ts.tv_nsec;
ip->i_modrev++;
}
if (ip->i_flag & IN_CHANGE) {
ip->i_ctime = ts.tv_sec;
ip->i_ctimensec = ts.tv_nsec;
}
}
ip->i_flag &= ~(IN_ACCESS | IN_CHANGE | IN_UPDATE);
}
void
ext2_itimes(struct vnode *vp)
{
VI_LOCK(vp);
ext2_itimes_locked(vp);
VI_UNLOCK(vp);
}
/*
* Create a regular file
*/
static int
ext2_create(struct vop_create_args *ap)
{
int error;
error =
ext2_makeinode(MAKEIMODE(ap->a_vap->va_type, ap->a_vap->va_mode),
ap->a_dvp, ap->a_vpp, ap->a_cnp);
if (error)
return (error);
return (0);
}
static int
ext2_open(struct vop_open_args *ap)
{
if (ap->a_vp->v_type == VBLK || ap->a_vp->v_type == VCHR)
return (EOPNOTSUPP);
/*
* Files marked append-only must be opened for appending.
*/
if ((VTOI(ap->a_vp)->i_flags & APPEND) &&
(ap->a_mode & (FWRITE | O_APPEND)) == FWRITE)
return (EPERM);
vnode_create_vobject(ap->a_vp, VTOI(ap->a_vp)->i_size, ap->a_td);
return (0);
}
/*
* Close called.
*
* Update the times on the inode.
*/
static int
ext2_close(struct vop_close_args *ap)
{
struct vnode *vp = ap->a_vp;
VI_LOCK(vp);
if (vp->v_usecount > 1)
ext2_itimes_locked(vp);
VI_UNLOCK(vp);
return (0);
}
static int
ext2_access(struct vop_access_args *ap)
{
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
accmode_t accmode = ap->a_accmode;
int error;
if (vp->v_type == VBLK || vp->v_type == VCHR)
return (EOPNOTSUPP);
/*
* Disallow write attempts on read-only file systems;
* unless the file is a socket, fifo, or a block or
* character device resident on the file system.
*/
if (accmode & VWRITE) {
switch (vp->v_type) {
case VDIR:
case VLNK:
case VREG:
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
break;
default:
break;
}
}
/* If immutable bit set, nobody gets to write it. */
if ((accmode & VWRITE) && (ip->i_flags & (SF_IMMUTABLE | SF_SNAPSHOT)))
return (EPERM);
error = vaccess(vp->v_type, ip->i_mode, ip->i_uid, ip->i_gid,
ap->a_accmode, ap->a_cred, NULL);
return (error);
}
static int
ext2_getattr(struct vop_getattr_args *ap)
{
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
struct vattr *vap = ap->a_vap;
ext2_itimes(vp);
/*
* Copy from inode table
*/
vap->va_fsid = dev2udev(ip->i_devvp->v_rdev);
vap->va_fileid = ip->i_number;
vap->va_mode = ip->i_mode & ~IFMT;
vap->va_nlink = ip->i_nlink;
vap->va_uid = ip->i_uid;
vap->va_gid = ip->i_gid;
vap->va_rdev = ip->i_rdev;
vap->va_size = ip->i_size;
vap->va_atime.tv_sec = ip->i_atime;
vap->va_atime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_atimensec : 0;
vap->va_mtime.tv_sec = ip->i_mtime;
vap->va_mtime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_mtimensec : 0;
vap->va_ctime.tv_sec = ip->i_ctime;
vap->va_ctime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_ctimensec : 0;
if E2DI_HAS_XTIME(ip) {
vap->va_birthtime.tv_sec = ip->i_birthtime;
vap->va_birthtime.tv_nsec = ip->i_birthnsec;
}
vap->va_flags = ip->i_flags;
vap->va_gen = ip->i_gen;
vap->va_blocksize = vp->v_mount->mnt_stat.f_iosize;
vap->va_bytes = dbtob((u_quad_t)ip->i_blocks);
vap->va_type = IFTOVT(ip->i_mode);
vap->va_filerev = ip->i_modrev;
return (0);
}
/*
* Set attribute vnode op. called from several syscalls
*/
static int
ext2_setattr(struct vop_setattr_args *ap)
{
struct vattr *vap = ap->a_vap;
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
struct ucred *cred = ap->a_cred;
struct thread *td = curthread;
int error;
/*
* Check for unsettable attributes.
*/
if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
(vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
(vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
return (EINVAL);
}
if (vap->va_flags != VNOVAL) {
/* Disallow flags not supported by ext2fs. */
if(vap->va_flags & ~(SF_APPEND | SF_IMMUTABLE | UF_NODUMP))
return (EOPNOTSUPP);
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
/*
* Callers may only modify the file flags on objects they
* have VADMIN rights for.
*/
if ((error = VOP_ACCESS(vp, VADMIN, cred, td)))
return (error);
/*
* Unprivileged processes and privileged processes in
* jail() are not permitted to unset system flags, or
* modify flags if any system flags are set.
* Privileged non-jail processes may not modify system flags
* if securelevel > 0 and any existing system flags are set.
*/
if (!priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0)) {
if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND)) {
error = securelevel_gt(cred, 0);
if (error)
return (error);
}
} else {
if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND) ||
((vap->va_flags ^ ip->i_flags) & SF_SETTABLE))
return (EPERM);
}
ip->i_flags = vap->va_flags;
ip->i_flag |= IN_CHANGE;
if (ip->i_flags & (IMMUTABLE | APPEND))
return (0);
}
if (ip->i_flags & (IMMUTABLE | APPEND))
return (EPERM);
/*
* Go through the fields and update iff not VNOVAL.
*/
if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if ((error = ext2_chown(vp, vap->va_uid, vap->va_gid, cred,
td)) != 0)
return (error);
}
if (vap->va_size != VNOVAL) {
/*
* Disallow write attempts on read-only file systems;
* unless the file is a socket, fifo, or a block or
* character device resident on the file system.
*/
switch (vp->v_type) {
case VDIR:
return (EISDIR);
case VLNK:
case VREG:
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
break;
default:
break;
}
if ((error = ext2_truncate(vp, vap->va_size, 0, cred, td)) != 0)
return (error);
}
if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
/*
* From utimes(2):
* If times is NULL, ... The caller must be the owner of
* the file, have permission to write the file, or be the
* super-user.
* If times is non-NULL, ... The caller must be the owner of
* the file or be the super-user.
*/
if ((error = VOP_ACCESS(vp, VADMIN, cred, td)) &&
((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
(error = VOP_ACCESS(vp, VWRITE, cred, td))))
return (error);
if (vap->va_atime.tv_sec != VNOVAL)
ip->i_flag |= IN_ACCESS;
if (vap->va_mtime.tv_sec != VNOVAL)
ip->i_flag |= IN_CHANGE | IN_UPDATE;
ext2_itimes(vp);
if (vap->va_atime.tv_sec != VNOVAL) {
ip->i_atime = vap->va_atime.tv_sec;
ip->i_atimensec = vap->va_atime.tv_nsec;
}
if (vap->va_mtime.tv_sec != VNOVAL) {
ip->i_mtime = vap->va_mtime.tv_sec;
ip->i_mtimensec = vap->va_mtime.tv_nsec;
}
ip->i_birthtime = vap->va_birthtime.tv_sec;
ip->i_birthnsec = vap->va_birthtime.tv_nsec;
error = ext2_update(vp, 0);
if (error)
return (error);
}
error = 0;
if (vap->va_mode != (mode_t)VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
error = ext2_chmod(vp, (int)vap->va_mode, cred, td);
}
return (error);
}
/*
* Change the mode on a file.
* Inode must be locked before calling.
*/
static int
ext2_chmod(struct vnode *vp, int mode, struct ucred *cred, struct thread *td)
{
struct inode *ip = VTOI(vp);
int error;
/*
* To modify the permissions on a file, must possess VADMIN
* for that file.
*/
if ((error = VOP_ACCESS(vp, VADMIN, cred, td)))
return (error);
/*
* Privileged processes may set the sticky bit on non-directories,
* as well as set the setgid bit on a file with a group that the
* process is not a member of.
*/
if (vp->v_type != VDIR && (mode & S_ISTXT)) {
error = priv_check_cred(cred, PRIV_VFS_STICKYFILE, 0);
if (error)
return (EFTYPE);
}
if (!groupmember(ip->i_gid, cred) && (mode & ISGID)) {
error = priv_check_cred(cred, PRIV_VFS_SETGID, 0);
if (error)
return (error);
}
ip->i_mode &= ~ALLPERMS;
ip->i_mode |= (mode & ALLPERMS);
ip->i_flag |= IN_CHANGE;
return (0);
}
/*
* Perform chown operation on inode ip;
* inode must be locked prior to call.
*/
static int
ext2_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred,
struct thread *td)
{
struct inode *ip = VTOI(vp);
uid_t ouid;
gid_t ogid;
int error = 0;
if (uid == (uid_t)VNOVAL)
uid = ip->i_uid;
if (gid == (gid_t)VNOVAL)
gid = ip->i_gid;
/*
* To modify the ownership of a file, must possess VADMIN
* for that file.
*/
if ((error = VOP_ACCESS(vp, VADMIN, cred, td)))
return (error);
/*
* To change the owner of a file, or change the group of a file
* to a group of which we are not a member, the caller must
* have privilege.
*/
if (uid != ip->i_uid || (gid != ip->i_gid &&
!groupmember(gid, cred))) {
error = priv_check_cred(cred, PRIV_VFS_CHOWN, 0);
if (error)
return (error);
}
ogid = ip->i_gid;
ouid = ip->i_uid;
ip->i_gid = gid;
ip->i_uid = uid;
ip->i_flag |= IN_CHANGE;
if ((ip->i_mode & (ISUID | ISGID)) && (ouid != uid || ogid != gid)) {
if (priv_check_cred(cred, PRIV_VFS_RETAINSUGID, 0) != 0)
ip->i_mode &= ~(ISUID | ISGID);
}
return (0);
}
/*
* Synch an open file.
*/
/* ARGSUSED */
static int
ext2_fsync(struct vop_fsync_args *ap)
{
/*
* Flush all dirty buffers associated with a vnode.
*/
vop_stdfsync(ap);
return (ext2_update(ap->a_vp, ap->a_waitfor == MNT_WAIT));
}
/*
* Mknod vnode call
*/
/* ARGSUSED */
static int
ext2_mknod(struct vop_mknod_args *ap)
{
struct vattr *vap = ap->a_vap;
struct vnode **vpp = ap->a_vpp;
struct inode *ip;
ino_t ino;
int error;
error = ext2_makeinode(MAKEIMODE(vap->va_type, vap->va_mode),
ap->a_dvp, vpp, ap->a_cnp);
if (error)
return (error);
ip = VTOI(*vpp);
ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
if (vap->va_rdev != VNOVAL) {
/*
* Want to be able to use this to make badblock
* inodes, so don't truncate the dev number.
*/
ip->i_rdev = vap->va_rdev;
}
/*
* Remove inode, then reload it through VFS_VGET so it is
* checked to see if it is an alias of an existing entry in
* the inode cache. XXX I don't believe this is necessary now.
*/
(*vpp)->v_type = VNON;
ino = ip->i_number; /* Save this before vgone() invalidates ip. */
vgone(*vpp);
vput(*vpp);
error = VFS_VGET(ap->a_dvp->v_mount, ino, LK_EXCLUSIVE, vpp);
if (error) {
*vpp = NULL;
return (error);
}
return (0);
}
static int
ext2_remove(struct vop_remove_args *ap)
{
struct inode *ip;
struct vnode *vp = ap->a_vp;
struct vnode *dvp = ap->a_dvp;
int error;
ip = VTOI(vp);
if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
(VTOI(dvp)->i_flags & APPEND)) {
error = EPERM;
goto out;
}
error = ext2_dirremove(dvp, ap->a_cnp);
if (error == 0) {
ip->i_nlink--;
ip->i_flag |= IN_CHANGE;
}
out:
return (error);
}
/*
* link vnode call
*/
static int
ext2_link(struct vop_link_args *ap)
{
struct vnode *vp = ap->a_vp;
struct vnode *tdvp = ap->a_tdvp;
struct componentname *cnp = ap->a_cnp;
struct inode *ip;
int error;
#ifdef INVARIANTS
if ((cnp->cn_flags & HASBUF) == 0)
panic("ext2_link: no name");
#endif
if (tdvp->v_mount != vp->v_mount) {
error = EXDEV;
goto out;
}
ip = VTOI(vp);
if ((nlink_t)ip->i_nlink >= EXT2_LINK_MAX) {
error = EMLINK;
goto out;
}
if (ip->i_flags & (IMMUTABLE | APPEND)) {
error = EPERM;
goto out;
}
ip->i_nlink++;
ip->i_flag |= IN_CHANGE;
error = ext2_update(vp, !DOINGASYNC(vp));
if (!error)
error = ext2_direnter(ip, tdvp, cnp);
if (error) {
ip->i_nlink--;
ip->i_flag |= IN_CHANGE;
}
out:
return (error);
}
/*
* Rename system call.
* rename("foo", "bar");
* is essentially
* unlink("bar");
* link("foo", "bar");
* unlink("foo");
* but ``atomically''. Can't do full commit without saving state in the
* inode on disk which isn't feasible at this time. Best we can do is
* always guarantee the target exists.
*
* Basic algorithm is:
*
* 1) Bump link count on source while we're linking it to the
* target. This also ensure the inode won't be deleted out
* from underneath us while we work (it may be truncated by
* a concurrent `trunc' or `open' for creation).
* 2) Link source to destination. If destination already exists,
* delete it first.
* 3) Unlink source reference to inode if still around. If a
* directory was moved and the parent of the destination
* is different from the source, patch the ".." entry in the
* directory.
*/
static int
ext2_rename(struct vop_rename_args *ap)
{
struct vnode *tvp = ap->a_tvp;
struct vnode *tdvp = ap->a_tdvp;
struct vnode *fvp = ap->a_fvp;
struct vnode *fdvp = ap->a_fdvp;
struct componentname *tcnp = ap->a_tcnp;
struct componentname *fcnp = ap->a_fcnp;
struct inode *ip, *xp, *dp;
struct dirtemplate dirbuf;
int doingdirectory = 0, oldparent = 0, newparent = 0;
int error = 0;
u_char namlen;
#ifdef INVARIANTS
if ((tcnp->cn_flags & HASBUF) == 0 ||
(fcnp->cn_flags & HASBUF) == 0)
panic("ext2_rename: no name");
#endif
/*
* Check for cross-device rename.
*/
if ((fvp->v_mount != tdvp->v_mount) ||
(tvp && (fvp->v_mount != tvp->v_mount))) {
error = EXDEV;
abortit:
if (tdvp == tvp)
vrele(tdvp);
else
vput(tdvp);
if (tvp)
vput(tvp);
vrele(fdvp);
vrele(fvp);
return (error);
}
if (tvp && ((VTOI(tvp)->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
(VTOI(tdvp)->i_flags & APPEND))) {
error = EPERM;
goto abortit;
}
/*
* Renaming a file to itself has no effect. The upper layers should
* not call us in that case. Temporarily just warn if they do.
*/
if (fvp == tvp) {
printf("ext2_rename: fvp == tvp (can't happen)\n");
error = 0;
goto abortit;
}
if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
goto abortit;
dp = VTOI(fdvp);
ip = VTOI(fvp);
if (ip->i_nlink >= EXT2_LINK_MAX) {
VOP_UNLOCK(fvp, 0);
error = EMLINK;
goto abortit;
}
if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))
|| (dp->i_flags & APPEND)) {
VOP_UNLOCK(fvp, 0);
error = EPERM;
goto abortit;
}
if ((ip->i_mode & IFMT) == IFDIR) {
/*
* Avoid ".", "..", and aliases of "." for obvious reasons.
*/
if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
dp == ip || (fcnp->cn_flags | tcnp->cn_flags) & ISDOTDOT ||
(ip->i_flag & IN_RENAME)) {
VOP_UNLOCK(fvp, 0);
error = EINVAL;
goto abortit;
}
ip->i_flag |= IN_RENAME;
oldparent = dp->i_number;
doingdirectory++;
}
vrele(fdvp);
/*
* When the target exists, both the directory
* and target vnodes are returned locked.
*/
dp = VTOI(tdvp);
xp = NULL;
if (tvp)
xp = VTOI(tvp);
/*
* 1) Bump link count while we're moving stuff
* around. If we crash somewhere before
* completing our work, the link count
* may be wrong, but correctable.
*/
ip->i_nlink++;
ip->i_flag |= IN_CHANGE;
if ((error = ext2_update(fvp, !DOINGASYNC(fvp))) != 0) {
VOP_UNLOCK(fvp, 0);
goto bad;
}
/*
* If ".." must be changed (ie the directory gets a new
* parent) then the source directory must not be in the
* directory hierarchy above the target, as this would
* orphan everything below the source directory. Also
* the user must have write permission in the source so
* as to be able to change "..". We must repeat the call
* to namei, as the parent directory is unlocked by the
* call to checkpath().
*/
error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_thread);
VOP_UNLOCK(fvp, 0);
if (oldparent != dp->i_number)
newparent = dp->i_number;
if (doingdirectory && newparent) {
if (error) /* write access check above */
goto bad;
if (xp != NULL)
vput(tvp);
error = ext2_checkpath(ip, dp, tcnp->cn_cred);
if (error)
goto out;
VREF(tdvp);
error = relookup(tdvp, &tvp, tcnp);
if (error)
goto out;
vrele(tdvp);
dp = VTOI(tdvp);
xp = NULL;
if (tvp)
xp = VTOI(tvp);
}
/*
* 2) If target doesn't exist, link the target
* to the source and unlink the source.
* Otherwise, rewrite the target directory
* entry to reference the source inode and
* expunge the original entry's existence.
*/
if (xp == NULL) {
if (dp->i_devvp != ip->i_devvp)
panic("ext2_rename: EXDEV");
/*
* Account for ".." in new directory.
* When source and destination have the same
* parent we don't fool with the link count.
*/
if (doingdirectory && newparent) {
if ((nlink_t)dp->i_nlink >= EXT2_LINK_MAX) {
error = EMLINK;
goto bad;
}
dp->i_nlink++;
dp->i_flag |= IN_CHANGE;
error = ext2_update(tdvp, !DOINGASYNC(tdvp));
if (error)
goto bad;
}
error = ext2_direnter(ip, tdvp, tcnp);
if (error) {
if (doingdirectory && newparent) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
(void)ext2_update(tdvp, 1);
}
goto bad;
}
vput(tdvp);
} else {
if (xp->i_devvp != dp->i_devvp || xp->i_devvp != ip->i_devvp)
panic("ext2_rename: EXDEV");
/*
* Short circuit rename(foo, foo).
*/
if (xp->i_number == ip->i_number)
panic("ext2_rename: same file");
/*
* If the parent directory is "sticky", then the user must
* own the parent directory, or the destination of the rename,
* otherwise the destination may not be changed (except by
* root). This implements append-only directories.
*/
if ((dp->i_mode & S_ISTXT) && tcnp->cn_cred->cr_uid != 0 &&
tcnp->cn_cred->cr_uid != dp->i_uid &&
xp->i_uid != tcnp->cn_cred->cr_uid) {
error = EPERM;
goto bad;
}
/*
* Target must be empty if a directory and have no links
* to it. Also, ensure source and target are compatible
* (both directories, or both not directories).
*/
if ((xp->i_mode&IFMT) == IFDIR) {
if (! ext2_dirempty(xp, dp->i_number, tcnp->cn_cred) ||
xp->i_nlink > 2) {
error = ENOTEMPTY;
goto bad;
}
if (!doingdirectory) {
error = ENOTDIR;
goto bad;
}
cache_purge(tdvp);
} else if (doingdirectory) {
error = EISDIR;
goto bad;
}
error = ext2_dirrewrite(dp, ip, tcnp);
if (error)
goto bad;
/*
* If the target directory is in the same
* directory as the source directory,
* decrement the link count on the parent
* of the target directory.
*/
if (doingdirectory && !newparent) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
}
vput(tdvp);
/*
* Adjust the link count of the target to
* reflect the dirrewrite above. If this is
* a directory it is empty and there are
* no links to it, so we can squash the inode and
* any space associated with it. We disallowed
* renaming over top of a directory with links to
* it above, as the remaining link would point to
* a directory without "." or ".." entries.
*/
xp->i_nlink--;
if (doingdirectory) {
if (--xp->i_nlink != 0)
panic("ext2_rename: linked directory");
error = ext2_truncate(tvp, (off_t)0, IO_SYNC,
tcnp->cn_cred, tcnp->cn_thread);
}
xp->i_flag |= IN_CHANGE;
vput(tvp);
xp = NULL;
}
/*
* 3) Unlink the source.
*/
fcnp->cn_flags &= ~MODMASK;
fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
VREF(fdvp);
error = relookup(fdvp, &fvp, fcnp);
if (error == 0)
vrele(fdvp);
if (fvp != NULL) {
xp = VTOI(fvp);
dp = VTOI(fdvp);
} else {
/*
* From name has disappeared.
*/
if (doingdirectory)
panic("ext2_rename: lost dir entry");
vrele(ap->a_fvp);
return (0);
}
/*
* Ensure that the directory entry still exists and has not
* changed while the new name has been entered. If the source is
* a file then the entry may have been unlinked or renamed. In
* either case there is no further work to be done. If the source
* is a directory then it cannot have been rmdir'ed; its link
* count of three would cause a rmdir to fail with ENOTEMPTY.
* The IN_RENAME flag ensures that it cannot be moved by another
* rename.
*/
if (xp != ip) {
if (doingdirectory)
panic("ext2_rename: lost dir entry");
} else {
/*
* If the source is a directory with a
* new parent, the link count of the old
* parent directory must be decremented
* and ".." set to point to the new parent.
*/
if (doingdirectory && newparent) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
error = vn_rdwr(UIO_READ, fvp, (caddr_t)&dirbuf,
sizeof(struct dirtemplate), (off_t)0,
UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK,
tcnp->cn_cred, NOCRED, NULL, NULL);
if (error == 0) {
/* Like ufs little-endian: */
namlen = dirbuf.dotdot_type;
if (namlen != 2 ||
dirbuf.dotdot_name[0] != '.' ||
dirbuf.dotdot_name[1] != '.') {
ext2_dirbad(xp, (doff_t)12,
"rename: mangled dir");
} else {
dirbuf.dotdot_ino = newparent;
(void) vn_rdwr(UIO_WRITE, fvp,
(caddr_t)&dirbuf,
sizeof(struct dirtemplate),
(off_t)0, UIO_SYSSPACE,
IO_NODELOCKED | IO_SYNC |
IO_NOMACCHECK, tcnp->cn_cred,
NOCRED, NULL, NULL);
cache_purge(fdvp);
}
}
}
error = ext2_dirremove(fdvp, fcnp);
if (!error) {
xp->i_nlink--;
xp->i_flag |= IN_CHANGE;
}
xp->i_flag &= ~IN_RENAME;
}
if (dp)
vput(fdvp);
if (xp)
vput(fvp);
vrele(ap->a_fvp);
return (error);
bad:
if (xp)
vput(ITOV(xp));
vput(ITOV(dp));
out:
if (doingdirectory)
ip->i_flag &= ~IN_RENAME;
if (vn_lock(fvp, LK_EXCLUSIVE) == 0) {
ip->i_nlink--;
ip->i_flag |= IN_CHANGE;
ip->i_flag &= ~IN_RENAME;
vput(fvp);
} else
vrele(fvp);
return (error);
}
/*
* Mkdir system call
*/
static int
ext2_mkdir(struct vop_mkdir_args *ap)
{
struct vnode *dvp = ap->a_dvp;
struct vattr *vap = ap->a_vap;
struct componentname *cnp = ap->a_cnp;
struct inode *ip, *dp;
struct vnode *tvp;
struct dirtemplate dirtemplate, *dtp;
int error, dmode;
#ifdef INVARIANTS
if ((cnp->cn_flags & HASBUF) == 0)
panic("ext2_mkdir: no name");
#endif
dp = VTOI(dvp);
if ((nlink_t)dp->i_nlink >= EXT2_LINK_MAX) {
error = EMLINK;
goto out;
}
dmode = vap->va_mode & 0777;
dmode |= IFDIR;
/*
* Must simulate part of ext2_makeinode here to acquire the inode,
* but not have it entered in the parent directory. The entry is
* made later after writing "." and ".." entries.
*/
error = ext2_valloc(dvp, dmode, cnp->cn_cred, &tvp);
if (error)
goto out;
ip = VTOI(tvp);
ip->i_gid = dp->i_gid;
#ifdef SUIDDIR
{
/*
* if we are hacking owners here, (only do this where told to)
* and we are not giving it TOO root, (would subvert quotas)
* then go ahead and give it to the other user.
* The new directory also inherits the SUID bit.
* If user's UID and dir UID are the same,
* 'give it away' so that the SUID is still forced on.
*/
if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
(dp->i_mode & ISUID) && dp->i_uid) {
dmode |= ISUID;
ip->i_uid = dp->i_uid;
} else {
ip->i_uid = cnp->cn_cred->cr_uid;
}
}
#else
ip->i_uid = cnp->cn_cred->cr_uid;
#endif
ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
ip->i_mode = dmode;
tvp->v_type = VDIR; /* Rest init'd in getnewvnode(). */
ip->i_nlink = 2;
if (cnp->cn_flags & ISWHITEOUT)
ip->i_flags |= UF_OPAQUE;
error = ext2_update(tvp, 1);
/*
* Bump link count in parent directory
* to reflect work done below. Should
* be done before reference is created
* so reparation is possible if we crash.
*/
dp->i_nlink++;
dp->i_flag |= IN_CHANGE;
error = ext2_update(dvp, !DOINGASYNC(dvp));
if (error)
goto bad;
/* Initialize directory with "." and ".." from static template. */
if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs,
EXT2F_INCOMPAT_FTYPE))
dtp = &mastertemplate;
else
dtp = &omastertemplate;
dirtemplate = *dtp;
dirtemplate.dot_ino = ip->i_number;
dirtemplate.dotdot_ino = dp->i_number;
/* note that in ext2 DIRBLKSIZ == blocksize, not DEV_BSIZE
* so let's just redefine it - for this function only
*/
#undef DIRBLKSIZ
#define DIRBLKSIZ VTOI(dvp)->i_e2fs->e2fs_bsize
dirtemplate.dotdot_reclen = DIRBLKSIZ - 12;
error = vn_rdwr(UIO_WRITE, tvp, (caddr_t)&dirtemplate,
sizeof(dirtemplate), (off_t)0, UIO_SYSSPACE,
IO_NODELOCKED | IO_SYNC | IO_NOMACCHECK, cnp->cn_cred, NOCRED,
NULL, NULL);
if (error) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
goto bad;
}
if (DIRBLKSIZ > VFSTOEXT2(dvp->v_mount)->um_mountp->mnt_stat.f_bsize)
/* XXX should grow with balloc() */
panic("ext2_mkdir: blksize");
else {
ip->i_size = DIRBLKSIZ;
ip->i_flag |= IN_CHANGE;
}
/* Directory set up, now install its entry in the parent directory. */
error = ext2_direnter(ip, dvp, cnp);
if (error) {
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
}
bad:
/*
* No need to do an explicit VOP_TRUNCATE here, vrele will do this
* for us because we set the link count to 0.
*/
if (error) {
ip->i_nlink = 0;
ip->i_flag |= IN_CHANGE;
vput(tvp);
} else
*ap->a_vpp = tvp;
out:
return (error);
#undef DIRBLKSIZ
#define DIRBLKSIZ DEV_BSIZE
}
/*
* Rmdir system call.
*/
static int
ext2_rmdir(struct vop_rmdir_args *ap)
{
struct vnode *vp = ap->a_vp;
struct vnode *dvp = ap->a_dvp;
struct componentname *cnp = ap->a_cnp;
struct inode *ip, *dp;
int error;
ip = VTOI(vp);
dp = VTOI(dvp);
/*
* Verify the directory is empty (and valid).
* (Rmdir ".." won't be valid since
* ".." will contain a reference to
* the current directory and thus be
* non-empty.)
*/
error = 0;
if (ip->i_nlink != 2 || !ext2_dirempty(ip, dp->i_number, cnp->cn_cred)) {
error = ENOTEMPTY;
goto out;
}
if ((dp->i_flags & APPEND)
|| (ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
error = EPERM;
goto out;
}
/*
* Delete reference to directory before purging
* inode. If we crash in between, the directory
* will be reattached to lost+found,
*/
error = ext2_dirremove(dvp, cnp);
if (error)
goto out;
dp->i_nlink--;
dp->i_flag |= IN_CHANGE;
cache_purge(dvp);
VOP_UNLOCK(dvp, 0);
/*
* Truncate inode. The only stuff left
* in the directory is "." and "..". The
* "." reference is inconsequential since
* we're quashing it. The ".." reference
* has already been adjusted above. We've
* removed the "." reference and the reference
* in the parent directory, but there may be
* other hard links so decrement by 2 and
* worry about them later.
*/
ip->i_nlink -= 2;
error = ext2_truncate(vp, (off_t)0, IO_SYNC, cnp->cn_cred,
cnp->cn_thread);
cache_purge(ITOV(ip));
if (vn_lock(dvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
VOP_UNLOCK(vp, 0);
vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
}
out:
return (error);
}
/*
* symlink -- make a symbolic link
*/
static int
ext2_symlink(struct vop_symlink_args *ap)
{
struct vnode *vp, **vpp = ap->a_vpp;
struct inode *ip;
int len, error;
error = ext2_makeinode(IFLNK | ap->a_vap->va_mode, ap->a_dvp,
vpp, ap->a_cnp);
if (error)
return (error);
vp = *vpp;
len = strlen(ap->a_target);
if (len < vp->v_mount->mnt_maxsymlinklen) {
ip = VTOI(vp);
bcopy(ap->a_target, (char *)ip->i_shortlink, len);
ip->i_size = len;
ip->i_flag |= IN_CHANGE | IN_UPDATE;
} else
error = vn_rdwr(UIO_WRITE, vp, ap->a_target, len, (off_t)0,
UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK,
ap->a_cnp->cn_cred, NOCRED, NULL, NULL);
if (error)
vput(vp);
return (error);
}
/*
* Return target name of a symbolic link
*/
static int
ext2_readlink(struct vop_readlink_args *ap)
{
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
int isize;
isize = ip->i_size;
if (isize < vp->v_mount->mnt_maxsymlinklen) {
uiomove((char *)ip->i_shortlink, isize, ap->a_uio);
return (0);
}
return (VOP_READ(vp, ap->a_uio, 0, ap->a_cred));
}
/*
* Calculate the logical to physical mapping if not done already,
* then call the device strategy routine.
*
* In order to be able to swap to a file, the ext2_bmaparray() operation may not
* deadlock on memory. See ext2_bmap() for details.
*/
static int
ext2_strategy(struct vop_strategy_args *ap)
{
struct buf *bp = ap->a_bp;
struct vnode *vp = ap->a_vp;
struct inode *ip;
struct bufobj *bo;
daddr_t blkno;
int error;
ip = VTOI(vp);
if (vp->v_type == VBLK || vp->v_type == VCHR)
panic("ext2_strategy: spec");
if (bp->b_blkno == bp->b_lblkno) {
error = ext2_bmaparray(vp, bp->b_lblkno, &blkno, NULL, NULL);
bp->b_blkno = blkno;
if (error) {
bp->b_error = error;
bp->b_ioflags |= BIO_ERROR;
bufdone(bp);
return (0);
}
if ((long)bp->b_blkno == -1)
vfs_bio_clrbuf(bp);
}
if ((long)bp->b_blkno == -1) {
bufdone(bp);
return (0);
}
bp->b_iooffset = dbtob(bp->b_blkno);
bo = VFSTOEXT2(vp->v_mount)->um_bo;
BO_STRATEGY(bo, bp);
return (0);
}
/*
* Print out the contents of an inode.
*/
static int
ext2_print(struct vop_print_args *ap)
{
struct vnode *vp = ap->a_vp;
struct inode *ip = VTOI(vp);
vn_printf(ip->i_devvp, "\tino %lu", (u_long)ip->i_number);
if (vp->v_type == VFIFO)
fifo_printinfo(vp);
printf("\n");
return (0);
}
/*
* Close wrapper for fifos.
*
* Update the times on the inode then do device close.
*/
static int
ext2fifo_close(struct vop_close_args *ap)
{
struct vnode *vp = ap->a_vp;
VI_LOCK(vp);
if (vp->v_usecount > 1)
ext2_itimes_locked(vp);
VI_UNLOCK(vp);
return (fifo_specops.vop_close(ap));
}
/*
* Kqfilter wrapper for fifos.
*
* Fall through to ext2 kqfilter routines if needed
*/
static int
ext2fifo_kqfilter(struct vop_kqfilter_args *ap)
{
int error;
error = fifo_specops.vop_kqfilter(ap);
if (error)
error = vfs_kqfilter(ap);
return (error);
}
/*
* Return POSIX pathconf information applicable to ext2 filesystems.
*/
static int
ext2_pathconf(struct vop_pathconf_args *ap)
{
int error = 0;
switch (ap->a_name) {
case _PC_LINK_MAX:
*ap->a_retval = EXT2_LINK_MAX;
break;
case _PC_NAME_MAX:
*ap->a_retval = NAME_MAX;
break;
case _PC_PATH_MAX:
*ap->a_retval = PATH_MAX;
break;
case _PC_PIPE_BUF:
*ap->a_retval = PIPE_BUF;
break;
case _PC_CHOWN_RESTRICTED:
*ap->a_retval = 1;
break;
case _PC_NO_TRUNC:
*ap->a_retval = 1;
break;
case _PC_MIN_HOLE_SIZE:
*ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize;
break;
case _PC_ASYNC_IO:
/* _PC_ASYNC_IO should have been handled by upper layers. */
KASSERT(0, ("_PC_ASYNC_IO should not get here"));
error = EINVAL;
break;
case _PC_PRIO_IO:
*ap->a_retval = 0;
break;
case _PC_SYNC_IO:
*ap->a_retval = 0;
break;
case _PC_ALLOC_SIZE_MIN:
*ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_bsize;
break;
case _PC_FILESIZEBITS:
*ap->a_retval = 64;
break;
case _PC_REC_INCR_XFER_SIZE:
*ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize;
break;
case _PC_REC_MAX_XFER_SIZE:
*ap->a_retval = -1; /* means ``unlimited'' */
break;
case _PC_REC_MIN_XFER_SIZE:
*ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize;
break;
case _PC_REC_XFER_ALIGN:
*ap->a_retval = PAGE_SIZE;
break;
case _PC_SYMLINK_MAX:
*ap->a_retval = MAXPATHLEN;
break;
default:
error = EINVAL;
break;
}
return (error);
}
/*
* Vnode pointer to File handle
*/
/* ARGSUSED */
static int
ext2_vptofh(struct vop_vptofh_args *ap)
{
struct inode *ip;
struct ufid *ufhp;
ip = VTOI(ap->a_vp);
ufhp = (struct ufid *)ap->a_fhp;
ufhp->ufid_len = sizeof(struct ufid);
ufhp->ufid_ino = ip->i_number;
ufhp->ufid_gen = ip->i_gen;
return (0);
}
/*
* Initialize the vnode associated with a new inode, handle aliased
* vnodes.
*/
int
ext2_vinit(struct mount *mntp, struct vop_vector *fifoops, struct vnode **vpp)
{
struct inode *ip;
struct vnode *vp;
vp = *vpp;
ip = VTOI(vp);
vp->v_type = IFTOVT(ip->i_mode);
if (vp->v_type == VFIFO)
vp->v_op = fifoops;
if (ip->i_number == EXT2_ROOTINO)
vp->v_vflag |= VV_ROOT;
ip->i_modrev = init_va_filerev();
*vpp = vp;
return (0);
}
/*
* Allocate a new inode.
*/
static int
ext2_makeinode(int mode, struct vnode *dvp, struct vnode **vpp,
struct componentname *cnp)
{
struct inode *ip, *pdir;
struct vnode *tvp;
int error;
pdir = VTOI(dvp);
#ifdef INVARIANTS
if ((cnp->cn_flags & HASBUF) == 0)
panic("ext2_makeinode: no name");
#endif
*vpp = NULL;
if ((mode & IFMT) == 0)
mode |= IFREG;
error = ext2_valloc(dvp, mode, cnp->cn_cred, &tvp);
if (error) {
return (error);
}
ip = VTOI(tvp);
ip->i_gid = pdir->i_gid;
#ifdef SUIDDIR
{
/*
* if we are
* not the owner of the directory,
* and we are hacking owners here, (only do this where told to)
* and we are not giving it TOO root, (would subvert quotas)
* then go ahead and give it to the other user.
* Note that this drops off the execute bits for security.
*/
if ( (dvp->v_mount->mnt_flag & MNT_SUIDDIR) &&
(pdir->i_mode & ISUID) &&
(pdir->i_uid != cnp->cn_cred->cr_uid) && pdir->i_uid) {
ip->i_uid = pdir->i_uid;
mode &= ~07111;
} else {
ip->i_uid = cnp->cn_cred->cr_uid;
}
}
#else
ip->i_uid = cnp->cn_cred->cr_uid;
#endif
ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE;
ip->i_mode = mode;
tvp->v_type = IFTOVT(mode); /* Rest init'd in getnewvnode(). */
ip->i_nlink = 1;
if ((ip->i_mode & ISGID) && !groupmember(ip->i_gid, cnp->cn_cred)) {
if (priv_check_cred(cnp->cn_cred, PRIV_VFS_RETAINSUGID, 0))
ip->i_mode &= ~ISGID;
}
if (cnp->cn_flags & ISWHITEOUT)
ip->i_flags |= UF_OPAQUE;
/*
* Make sure inode goes to disk before directory entry.
*/
error = ext2_update(tvp, !DOINGASYNC(tvp));
if (error)
goto bad;
error = ext2_direnter(ip, dvp, cnp);
if (error)
goto bad;
*vpp = tvp;
return (0);
bad:
/*
* Write error occurred trying to update the inode
* or the directory so must deallocate the inode.
*/
ip->i_nlink = 0;
ip->i_flag |= IN_CHANGE;
vput(tvp);
return (error);
}
/*
* Vnode op for reading.
*/
static int
ext2_read(struct vop_read_args *ap)
{
struct vnode *vp;
struct inode *ip;
int error;
vp = ap->a_vp;
ip = VTOI(vp);
/*EXT4_EXT_LOCK(ip);*/
if (ip->i_flags & EXT4_EXTENTS)
error = ext4_ext_read(ap);
else
error = ext2_ind_read(ap);
/*EXT4_EXT_UNLOCK(ip);*/
return (error);
}
/*
* Vnode op for reading.
*/
static int
ext2_ind_read(struct vop_read_args *ap)
{
struct vnode *vp;
struct inode *ip;
struct uio *uio;
struct m_ext2fs *fs;
struct buf *bp;
daddr_t lbn, nextlbn;
off_t bytesinfile;
long size, xfersize, blkoffset;
int error, orig_resid, seqcount;
int ioflag;
vp = ap->a_vp;
uio = ap->a_uio;
ioflag = ap->a_ioflag;
seqcount = ap->a_ioflag >> IO_SEQSHIFT;
ip = VTOI(vp);
#ifdef INVARIANTS
if (uio->uio_rw != UIO_READ)
panic("%s: mode", "ext2_read");
if (vp->v_type == VLNK) {
if ((int)ip->i_size < vp->v_mount->mnt_maxsymlinklen)
panic("%s: short symlink", "ext2_read");
} else if (vp->v_type != VREG && vp->v_type != VDIR)
panic("%s: type %d", "ext2_read", vp->v_type);
#endif
orig_resid = uio->uio_resid;
KASSERT(orig_resid >= 0, ("ext2_read: uio->uio_resid < 0"));
if (orig_resid == 0)
return (0);
KASSERT(uio->uio_offset >= 0, ("ext2_read: uio->uio_offset < 0"));
fs = ip->i_e2fs;
if (uio->uio_offset < ip->i_size &&
uio->uio_offset >= fs->e2fs_maxfilesize)
return (EOVERFLOW);
for (error = 0, bp = NULL; uio->uio_resid > 0; bp = NULL) {
if ((bytesinfile = ip->i_size - uio->uio_offset) <= 0)
break;
lbn = lblkno(fs, uio->uio_offset);
nextlbn = lbn + 1;
size = blksize(fs, ip, lbn);
blkoffset = blkoff(fs, uio->uio_offset);
xfersize = fs->e2fs_fsize - blkoffset;
if (uio->uio_resid < xfersize)
xfersize = uio->uio_resid;
if (bytesinfile < xfersize)
xfersize = bytesinfile;
if (lblktosize(fs, nextlbn) >= ip->i_size)
error = bread(vp, lbn, size, NOCRED, &bp);
else if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
error = cluster_read(vp, ip->i_size, lbn, size,
NOCRED, blkoffset + uio->uio_resid, seqcount,
0, &bp);
} else if (seqcount > 1) {
int nextsize = blksize(fs, ip, nextlbn);
error = breadn(vp, lbn,
size, &nextlbn, &nextsize, 1, NOCRED, &bp);
} else
error = bread(vp, lbn, size, NOCRED, &bp);
if (error) {
brelse(bp);
bp = NULL;
break;
}
/*
* If IO_DIRECT then set B_DIRECT for the buffer. This
* will cause us to attempt to release the buffer later on
* and will cause the buffer cache to attempt to free the
* underlying pages.
*/
if (ioflag & IO_DIRECT)
bp->b_flags |= B_DIRECT;
/*
* We should only get non-zero b_resid when an I/O error
* has occurred, which should cause us to break above.
* However, if the short read did not cause an error,
* then we want to ensure that we do not uiomove bad
* or uninitialized data.
*/
size -= bp->b_resid;
if (size < xfersize) {
if (size == 0)
break;
xfersize = size;
}
error = uiomove((char *)bp->b_data + blkoffset,
(int)xfersize, uio);
if (error)
break;
if (ioflag & (IO_VMIO|IO_DIRECT)) {
/*
* If it's VMIO or direct I/O, then we don't
* need the buf, mark it available for
* freeing. If it's non-direct VMIO, the VM has
* the data.
*/
bp->b_flags |= B_RELBUF;
brelse(bp);
} else {
/*
* Otherwise let whoever
* made the request take care of
* freeing it. We just queue
* it onto another list.
*/
bqrelse(bp);
}
}
/*
* This can only happen in the case of an error
* because the loop above resets bp to NULL on each iteration
* and on normal completion has not set a new value into it.
* so it must have come from a 'break' statement
*/
if (bp != NULL) {
if (ioflag & (IO_VMIO|IO_DIRECT)) {
bp->b_flags |= B_RELBUF;
brelse(bp);
} else {
bqrelse(bp);
}
}
if ((error == 0 || uio->uio_resid != orig_resid) &&
(vp->v_mount->mnt_flag & MNT_NOATIME) == 0)
ip->i_flag |= IN_ACCESS;
return (error);
}
static int
ext2_ioctl(struct vop_ioctl_args *ap)
{
switch (ap->a_command) {
case FIOSEEKDATA:
case FIOSEEKHOLE:
return (vn_bmap_seekhole(ap->a_vp, ap->a_command,
(off_t *)ap->a_data, ap->a_cred));
default:
return (ENOTTY);
}
}
/*
* this function handles ext4 extents block mapping
*/
static int
ext4_ext_read(struct vop_read_args *ap)
{
struct vnode *vp;
struct inode *ip;
struct uio *uio;
struct m_ext2fs *fs;
struct buf *bp;
struct ext4_extent nex, *ep;
struct ext4_extent_path path;
daddr_t lbn, newblk;
off_t bytesinfile;
int cache_type;
ssize_t orig_resid;
int error;
long size, xfersize, blkoffset;
vp = ap->a_vp;
ip = VTOI(vp);
uio = ap->a_uio;
memset(&path, 0, sizeof(path));
orig_resid = uio->uio_resid;
KASSERT(orig_resid >= 0, ("%s: uio->uio_resid < 0", __func__));
if (orig_resid == 0)
return (0);
KASSERT(uio->uio_offset >= 0, ("%s: uio->uio_offset < 0", __func__));
fs = ip->i_e2fs;
if (uio->uio_offset < ip->i_size && uio->uio_offset >= fs->e2fs_maxfilesize)
return (EOVERFLOW);
while (uio->uio_resid > 0) {
if ((bytesinfile = ip->i_size - uio->uio_offset) <= 0)
break;
lbn = lblkno(fs, uio->uio_offset);
size = blksize(fs, ip, lbn);
blkoffset = blkoff(fs, uio->uio_offset);
xfersize = fs->e2fs_fsize - blkoffset;
xfersize = MIN(xfersize, uio->uio_resid);
xfersize = MIN(xfersize, bytesinfile);
/* get block from ext4 extent cache */
cache_type = ext4_ext_in_cache(ip, lbn, &nex);
switch (cache_type) {
case EXT4_EXT_CACHE_NO:
ext4_ext_find_extent(fs, ip, lbn, &path);
ep = path.ep_ext;
if (ep == NULL)
return (EIO);
ext4_ext_put_cache(ip, ep, EXT4_EXT_CACHE_IN);
newblk = lbn - ep->e_blk + (ep->e_start_lo |
(daddr_t)ep->e_start_hi << 32);
if (path.ep_bp != NULL) {
brelse(path.ep_bp);
path.ep_bp = NULL;
}
break;
case EXT4_EXT_CACHE_GAP:
/* block has not been allocated yet */
return (0);
case EXT4_EXT_CACHE_IN:
newblk = lbn - nex.e_blk + (nex.e_start_lo |
(daddr_t)nex.e_start_hi << 32);
break;
default:
panic("%s: invalid cache type", __func__);
}
error = bread(ip->i_devvp, fsbtodb(fs, newblk), size, NOCRED, &bp);
if (error) {
brelse(bp);
return (error);
}
size -= bp->b_resid;
if (size < xfersize) {
if (size == 0) {
bqrelse(bp);
break;
}
xfersize = size;
}
error = uiomove(bp->b_data + blkoffset, (int)xfersize, uio);
bqrelse(bp);
if (error)
return (error);
}
return (0);
}
/*
* Vnode op for writing.
*/
static int
ext2_write(struct vop_write_args *ap)
{
struct vnode *vp;
struct uio *uio;
struct inode *ip;
struct m_ext2fs *fs;
struct buf *bp;
daddr_t lbn;
off_t osize;
int blkoffset, error, flags, ioflag, resid, size, seqcount, xfersize;
ioflag = ap->a_ioflag;
uio = ap->a_uio;
vp = ap->a_vp;
seqcount = ioflag >> IO_SEQSHIFT;
ip = VTOI(vp);
#ifdef INVARIANTS
if (uio->uio_rw != UIO_WRITE)
panic("%s: mode", "ext2_write");
#endif
switch (vp->v_type) {
case VREG:
if (ioflag & IO_APPEND)
uio->uio_offset = ip->i_size;
if ((ip->i_flags & APPEND) && uio->uio_offset != ip->i_size)
return (EPERM);
/* FALLTHROUGH */
case VLNK:
break;
case VDIR:
/* XXX differs from ffs -- this is called from ext2_mkdir(). */
if ((ioflag & IO_SYNC) == 0)
panic("ext2_write: nonsync dir write");
break;
default:
panic("ext2_write: type %p %d (%jd,%jd)", (void *)vp,
vp->v_type, (intmax_t)uio->uio_offset,
(intmax_t)uio->uio_resid);
}
KASSERT(uio->uio_resid >= 0, ("ext2_write: uio->uio_resid < 0"));
KASSERT(uio->uio_offset >= 0, ("ext2_write: uio->uio_offset < 0"));
fs = ip->i_e2fs;
if ((uoff_t)uio->uio_offset + uio->uio_resid > fs->e2fs_maxfilesize)
return (EFBIG);
/*
* Maybe this should be above the vnode op call, but so long as
* file servers have no limits, I don't think it matters.
*/
if (vn_rlimit_fsize(vp, uio, uio->uio_td))
return (EFBIG);
resid = uio->uio_resid;
osize = ip->i_size;
if (seqcount > BA_SEQMAX)
flags = BA_SEQMAX << BA_SEQSHIFT;
else
flags = seqcount << BA_SEQSHIFT;
if ((ioflag & IO_SYNC) && !DOINGASYNC(vp))
flags |= IO_SYNC;
for (error = 0; uio->uio_resid > 0;) {
lbn = lblkno(fs, uio->uio_offset);
blkoffset = blkoff(fs, uio->uio_offset);
xfersize = fs->e2fs_fsize - blkoffset;
if (uio->uio_resid < xfersize)
xfersize = uio->uio_resid;
if (uio->uio_offset + xfersize > ip->i_size)
vnode_pager_setsize(vp, uio->uio_offset + xfersize);
/*
* We must perform a read-before-write if the transfer size
* does not cover the entire buffer.
*/
if (fs->e2fs_bsize > xfersize)
flags |= BA_CLRBUF;
else
flags &= ~BA_CLRBUF;
error = ext2_balloc(ip, lbn, blkoffset + xfersize,
ap->a_cred, &bp, flags);
if (error != 0)
break;
if ((ioflag & (IO_SYNC|IO_INVAL)) == (IO_SYNC|IO_INVAL))
bp->b_flags |= B_NOCACHE;
if (uio->uio_offset + xfersize > ip->i_size)
ip->i_size = uio->uio_offset + xfersize;
size = blksize(fs, ip, lbn) - bp->b_resid;
if (size < xfersize)
xfersize = size;
error =
uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio);
/*
* If the buffer is not already filled and we encounter an
* error while trying to fill it, we have to clear out any
* garbage data from the pages instantiated for the buffer.
* If we do not, a failed uiomove() during a write can leave
* the prior contents of the pages exposed to a userland mmap.
*
* Note that we need only clear buffers with a transfer size
* equal to the block size because buffers with a shorter
* transfer size were cleared above by the call to ext2_balloc()
* with the BA_CLRBUF flag set.
*
* If the source region for uiomove identically mmaps the
* buffer, uiomove() performed the NOP copy, and the buffer
* content remains valid because the page fault handler
* validated the pages.
*/
if (error != 0 && (bp->b_flags & B_CACHE) == 0 &&
fs->e2fs_bsize == xfersize)
vfs_bio_clrbuf(bp);
if (ioflag & (IO_VMIO|IO_DIRECT)) {
bp->b_flags |= B_RELBUF;
}
/*
* If IO_SYNC each buffer is written synchronously. Otherwise
* if we have a severe page deficiency write the buffer
* asynchronously. Otherwise try to cluster, and if that
* doesn't do it then either do an async write (if O_DIRECT),
* or a delayed write (if not).
*/
if (ioflag & IO_SYNC) {
(void)bwrite(bp);
} else if (vm_page_count_severe() ||
buf_dirty_count_severe() ||
(ioflag & IO_ASYNC)) {
bp->b_flags |= B_CLUSTEROK;
bawrite(bp);
} else if (xfersize + blkoffset == fs->e2fs_fsize) {
if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) {
bp->b_flags |= B_CLUSTEROK;
cluster_write(vp, bp, ip->i_size, seqcount, 0);
} else {
bawrite(bp);
}
} else if (ioflag & IO_DIRECT) {
bp->b_flags |= B_CLUSTEROK;
bawrite(bp);
} else {
bp->b_flags |= B_CLUSTEROK;
bdwrite(bp);
}
if (error || xfersize == 0)
break;
}
/*
* If we successfully wrote any data, and we are not the superuser
* we clear the setuid and setgid bits as a precaution against
* tampering.
*/
if ((ip->i_mode & (ISUID | ISGID)) && resid > uio->uio_resid &&
ap->a_cred) {
if (priv_check_cred(ap->a_cred, PRIV_VFS_RETAINSUGID, 0))
ip->i_mode &= ~(ISUID | ISGID);
}
if (error) {
if (ioflag & IO_UNIT) {
(void)ext2_truncate(vp, osize,
ioflag & IO_SYNC, ap->a_cred, uio->uio_td);
uio->uio_offset -= resid - uio->uio_resid;
uio->uio_resid = resid;
}
}
if (uio->uio_resid != resid) {
ip->i_flag |= IN_CHANGE | IN_UPDATE;
if (ioflag & IO_SYNC)
error = ext2_update(vp, 1);
}
return (error);
}
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