+/*
+ * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
+ * All rights reserved.
+ *
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 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.
+ *
+ * @(#)vfs_vnops.c 7.33 (Berkeley) 6/27/91
+ */
+
+#include "param.h"
+#include "systm.h"
+#include "kernel.h"
+#include "file.h"
+#include "stat.h"
+#include "buf.h"
+#include "proc.h"
+#include "mount.h"
+#include "namei.h"
+#include "vnode.h"
+#include "ioctl.h"
+#include "tty.h"
+
+struct fileops vnops =
+ { vn_read, vn_write, vn_ioctl, vn_select, vn_closefile };
+
+/*
+ * Common code for vnode open operations.
+ * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
+ */
+vn_open(ndp, p, fmode, cmode)
+ register struct nameidata *ndp;
+ struct proc *p;
+ int fmode, cmode;
+{
+ register struct vnode *vp;
+ register struct ucred *cred = p->p_ucred;
+ struct vattr vat;
+ struct vattr *vap = &vat;
+ int error;
+
+ if (fmode & O_CREAT) {
+ ndp->ni_nameiop = CREATE | LOCKPARENT | LOCKLEAF;
+ if ((fmode & O_EXCL) == 0)
+ ndp->ni_nameiop |= FOLLOW;
+ if (error = namei(ndp, p))
+ return (error);
+ if (ndp->ni_vp == NULL) {
+ VATTR_NULL(vap);
+ vap->va_type = VREG;
+ vap->va_mode = cmode;
+ if (error = VOP_CREATE(ndp, vap, p))
+ return (error);
+ fmode &= ~O_TRUNC;
+ vp = ndp->ni_vp;
+ } else {
+ VOP_ABORTOP(ndp);
+ if (ndp->ni_dvp == ndp->ni_vp)
+ vrele(ndp->ni_dvp);
+ else
+ vput(ndp->ni_dvp);
+ ndp->ni_dvp = NULL;
+ vp = ndp->ni_vp;
+ if (fmode & O_EXCL) {
+ error = EEXIST;
+ goto bad;
+ }
+ fmode &= ~O_CREAT;
+ }
+ } else {
+ ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
+ if (error = namei(ndp, p))
+ return (error);
+ vp = ndp->ni_vp;
+ }
+ if (vp->v_type == VSOCK) {
+ error = EOPNOTSUPP;
+ goto bad;
+ }
+ if ((fmode & O_CREAT) == 0) {
+ if (fmode & FREAD) {
+ if (error = VOP_ACCESS(vp, VREAD, cred, p))
+ goto bad;
+ }
+ if (fmode & (FWRITE | O_TRUNC)) {
+ if (vp->v_type == VDIR) {
+ error = EISDIR;
+ goto bad;
+ }
+ if ((error = vn_writechk(vp)) ||
+ (error = VOP_ACCESS(vp, VWRITE, cred, p)))
+ goto bad;
+ }
+ }
+ if (fmode & O_TRUNC) {
+ VATTR_NULL(vap);
+ vap->va_size = 0;
+ if (error = VOP_SETATTR(vp, vap, cred, p))
+ goto bad;
+ }
+ if (error = VOP_OPEN(vp, fmode, cred, p))
+ goto bad;
+ if (fmode & FWRITE)
+ vp->v_writecount++;
+ return (0);
+bad:
+ vput(vp);
+ return (error);
+}
+
+/*
+ * Check for write permissions on the specified vnode.
+ * The read-only status of the file system is checked.
+ * Also, prototype text segments cannot be written.
+ */
+vn_writechk(vp)
+ register struct vnode *vp;
+{
+
+ /*
+ * Disallow write attempts on read-only file systems;
+ * unless the file is a socket or a block or character
+ * device resident on the file system.
+ */
+ if (vp->v_mount->mnt_flag & MNT_RDONLY) {
+ switch (vp->v_type) {
+ case VREG: case VDIR: case VLNK:
+ return (EROFS);
+ }
+ }
+ /*
+ * If there's shared text associated with
+ * the vnode, try to free it up once. If
+ * we fail, we can't allow writing.
+ */
+ if ((vp->v_flag & VTEXT) && !vnode_pager_uncache(vp))
+ return (ETXTBSY);
+ return (0);
+}
+
+/*
+ * Vnode close call
+ */
+vn_close(vp, flags, cred, p)
+ register struct vnode *vp;
+ int flags;
+ struct ucred *cred;
+ struct proc *p;
+{
+ int error;
+
+ if (flags & FWRITE)
+ vp->v_writecount--;
+ error = VOP_CLOSE(vp, flags, cred, p);
+ vrele(vp);
+ return (error);
+}
+
+/*
+ * Package up an I/O request on a vnode into a uio and do it.
+ * [internal interface to file i/o for kernel only]
+ */
+vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p)
+ enum uio_rw rw;
+ struct vnode *vp;
+ caddr_t base;
+ int len;
+ off_t offset;
+ enum uio_seg segflg;
+ int ioflg;
+ struct ucred *cred;
+ int *aresid;
+ struct proc *p;
+{
+ struct uio auio;
+ struct iovec aiov;
+ int error;
+
+ if ((ioflg & IO_NODELOCKED) == 0)
+ VOP_LOCK(vp);
+ auio.uio_iov = &aiov;
+ auio.uio_iovcnt = 1;
+ aiov.iov_base = base;
+ aiov.iov_len = len;
+ auio.uio_resid = len;
+ auio.uio_offset = offset;
+ auio.uio_segflg = segflg;
+ auio.uio_rw = rw;
+ auio.uio_procp = p;
+ if (rw == UIO_READ)
+ error = VOP_READ(vp, &auio, ioflg, cred);
+ else
+ error = VOP_WRITE(vp, &auio, ioflg, cred);
+ if (aresid)
+ *aresid = auio.uio_resid;
+ else
+ if (auio.uio_resid && error == 0)
+ error = EIO;
+ if ((ioflg & IO_NODELOCKED) == 0)
+ VOP_UNLOCK(vp);
+ return (error);
+}
+
+/*
+ * File table vnode read routine.
+ */
+vn_read(fp, uio, cred)
+ struct file *fp;
+ struct uio *uio;
+ struct ucred *cred;
+{
+ register struct vnode *vp = (struct vnode *)fp->f_data;
+ int count, error;
+
+ VOP_LOCK(vp);
+ uio->uio_offset = fp->f_offset;
+ count = uio->uio_resid;
+ error = VOP_READ(vp, uio, (fp->f_flag & FNONBLOCK) ? IO_NDELAY : 0,
+ cred);
+ fp->f_offset += count - uio->uio_resid;
+ VOP_UNLOCK(vp);
+ return (error);
+}
+
+/*
+ * File table vnode write routine.
+ */
+vn_write(fp, uio, cred)
+ struct file *fp;
+ struct uio *uio;
+ struct ucred *cred;
+{
+ register struct vnode *vp = (struct vnode *)fp->f_data;
+ int count, error, ioflag = 0;
+
+ if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
+ ioflag |= IO_APPEND;
+ if (fp->f_flag & FNONBLOCK)
+ ioflag |= IO_NDELAY;
+ VOP_LOCK(vp);
+ uio->uio_offset = fp->f_offset;
+ count = uio->uio_resid;
+ error = VOP_WRITE(vp, uio, ioflag, cred);
+ if (ioflag & IO_APPEND)
+ fp->f_offset = uio->uio_offset;
+ else
+ fp->f_offset += count - uio->uio_resid;
+ VOP_UNLOCK(vp);
+ return (error);
+}
+
+/*
+ * File table vnode stat routine.
+ */
+vn_stat(vp, sb, p)
+ struct vnode *vp;
+ register struct stat *sb;
+ struct proc *p;
+{
+ struct vattr vattr;
+ register struct vattr *vap;
+ int error;
+ u_short mode;
+
+ vap = &vattr;
+ error = VOP_GETATTR(vp, vap, p->p_ucred, p);
+ if (error)
+ return (error);
+ /*
+ * Copy from vattr table
+ */
+ sb->st_dev = vap->va_fsid;
+ sb->st_ino = vap->va_fileid;
+ mode = vap->va_mode;
+ switch (vp->v_type) {
+ case VREG:
+ mode |= S_IFREG;
+ break;
+ case VDIR:
+ mode |= S_IFDIR;
+ break;
+ case VBLK:
+ mode |= S_IFBLK;
+ break;
+ case VCHR:
+ mode |= S_IFCHR;
+ break;
+ case VLNK:
+ mode |= S_IFLNK;
+ break;
+ case VSOCK:
+ mode |= S_IFSOCK;
+ break;
+ case VFIFO:
+ mode |= S_IFIFO;
+ break;
+ default:
+ return (EBADF);
+ };
+ sb->st_mode = mode;
+ sb->st_nlink = vap->va_nlink;
+ sb->st_uid = vap->va_uid;
+ sb->st_gid = vap->va_gid;
+ sb->st_rdev = vap->va_rdev;
+ sb->st_size = vap->va_size;
+ sb->st_atime = vap->va_atime.tv_sec;
+ sb->st_spare1 = 0;
+ sb->st_mtime = vap->va_mtime.tv_sec;
+ sb->st_spare2 = 0;
+ sb->st_ctime = vap->va_ctime.tv_sec;
+ sb->st_spare3 = 0;
+ sb->st_blksize = vap->va_blocksize;
+ sb->st_flags = vap->va_flags;
+ sb->st_gen = vap->va_gen;
+ sb->st_blocks = vap->va_bytes / S_BLKSIZE;
+ return (0);
+}
+
+/*
+ * File table vnode ioctl routine.
+ */
+vn_ioctl(fp, com, data, p)
+ struct file *fp;
+ int com;
+ caddr_t data;
+ struct proc *p;
+{
+ register struct vnode *vp = ((struct vnode *)fp->f_data);
+ struct vattr vattr;
+ int error;
+
+ switch (vp->v_type) {
+
+ case VREG:
+ case VDIR:
+ if (com == FIONREAD) {
+ if (error = VOP_GETATTR(vp, &vattr, p->p_ucred, p))
+ return (error);
+ *(off_t *)data = vattr.va_size - fp->f_offset;
+ return (0);
+ }
+ if (com == FIONBIO || com == FIOASYNC) /* XXX */
+ return (0); /* XXX */
+ /* fall into ... */
+
+ default:
+ return (ENOTTY);
+
+ case VFIFO:
+ case VCHR:
+ case VBLK:
+ error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p);
+ if (error == 0 && com == TIOCSCTTY) {
+ p->p_session->s_ttyvp = vp;
+ VREF(vp);
+ }
+ return (error);
+ }
+}
+
+/*
+ * File table vnode select routine.
+ */
+vn_select(fp, which, p)
+ struct file *fp;
+ int which;
+ struct proc *p;
+{
+
+ return (VOP_SELECT(((struct vnode *)fp->f_data), which, fp->f_flag,
+ fp->f_cred, p));
+}
+
+/*
+ * File table vnode close routine.
+ */
+vn_closefile(fp, p)
+ struct file *fp;
+ struct proc *p;
+{
+
+ return (vn_close(((struct vnode *)fp->f_data), fp->f_flag,
+ fp->f_cred, p));
+}
+
+/*
+ * vn_fhtovp() - convert a fh to a vnode ptr (optionally locked)
+ * - look up fsid in mount list (if not found ret error)
+ * - get vp by calling VFS_FHTOVP() macro
+ * - if lockflag lock it with VOP_LOCK()
+ */
+vn_fhtovp(fhp, lockflag, vpp)
+ fhandle_t *fhp;
+ int lockflag;
+ struct vnode **vpp;
+{
+ register struct mount *mp;
+
+ if ((mp = getvfs(&fhp->fh_fsid)) == NULL)
+ return (ESTALE);
+ if (VFS_FHTOVP(mp, &fhp->fh_fid, vpp))
+ return (ESTALE);
+ if (!lockflag)
+ VOP_UNLOCK(*vpp);
+ return (0);
+}
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