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vfs_vnops.c revision 1.169.2.2
      1 /*	$NetBSD: vfs_vnops.c,v 1.169.2.2 2010/08/17 06:47:34 uebayasi Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2009 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Andrew Doran.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1982, 1986, 1989, 1993
     34  *	The Regents of the University of California.  All rights reserved.
     35  * (c) UNIX System Laboratories, Inc.
     36  * All or some portions of this file are derived from material licensed
     37  * to the University of California by American Telephone and Telegraph
     38  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
     39  * the permission of UNIX System Laboratories, Inc.
     40  *
     41  * Redistribution and use in source and binary forms, with or without
     42  * modification, are permitted provided that the following conditions
     43  * are met:
     44  * 1. Redistributions of source code must retain the above copyright
     45  *    notice, this list of conditions and the following disclaimer.
     46  * 2. Redistributions in binary form must reproduce the above copyright
     47  *    notice, this list of conditions and the following disclaimer in the
     48  *    documentation and/or other materials provided with the distribution.
     49  * 3. Neither the name of the University nor the names of its contributors
     50  *    may be used to endorse or promote products derived from this software
     51  *    without specific prior written permission.
     52  *
     53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     63  * SUCH DAMAGE.
     64  *
     65  *	@(#)vfs_vnops.c	8.14 (Berkeley) 6/15/95
     66  */
     67 
     68 #include <sys/cdefs.h>
     69 __KERNEL_RCSID(0, "$NetBSD: vfs_vnops.c,v 1.169.2.2 2010/08/17 06:47:34 uebayasi Exp $");
     70 
     71 #include "veriexec.h"
     72 
     73 #include <sys/param.h>
     74 #include <sys/systm.h>
     75 #include <sys/kernel.h>
     76 #include <sys/file.h>
     77 #include <sys/stat.h>
     78 #include <sys/buf.h>
     79 #include <sys/proc.h>
     80 #include <sys/mount.h>
     81 #include <sys/namei.h>
     82 #include <sys/vnode.h>
     83 #include <sys/ioctl.h>
     84 #include <sys/tty.h>
     85 #include <sys/poll.h>
     86 #include <sys/kauth.h>
     87 #include <sys/syslog.h>
     88 #include <sys/fstrans.h>
     89 #include <sys/atomic.h>
     90 #include <sys/filedesc.h>
     91 #include <sys/wapbl.h>
     92 
     93 #include <miscfs/specfs/specdev.h>
     94 #include <miscfs/fifofs/fifo.h>
     95 
     96 #include <uvm/uvm_extern.h>
     97 #include <uvm/uvm_readahead.h>
     98 
     99 #ifdef UNION
    100 #include <fs/union/union.h>
    101 #endif
    102 
    103 int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct lwp *);
    104 
    105 #include <sys/verified_exec.h>
    106 
    107 static int vn_read(file_t *fp, off_t *offset, struct uio *uio,
    108 	    kauth_cred_t cred, int flags);
    109 static int vn_write(file_t *fp, off_t *offset, struct uio *uio,
    110 	    kauth_cred_t cred, int flags);
    111 static int vn_closefile(file_t *fp);
    112 static int vn_poll(file_t *fp, int events);
    113 static int vn_fcntl(file_t *fp, u_int com, void *data);
    114 static int vn_statfile(file_t *fp, struct stat *sb);
    115 static int vn_ioctl(file_t *fp, u_long com, void *data);
    116 
    117 const struct fileops vnops = {
    118 	.fo_read = vn_read,
    119 	.fo_write = vn_write,
    120 	.fo_ioctl = vn_ioctl,
    121 	.fo_fcntl = vn_fcntl,
    122 	.fo_poll = vn_poll,
    123 	.fo_stat = vn_statfile,
    124 	.fo_close = vn_closefile,
    125 	.fo_kqfilter = vn_kqfilter,
    126 	.fo_restart = fnullop_restart,
    127 };
    128 
    129 /*
    130  * Common code for vnode open operations.
    131  * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
    132  */
    133 int
    134 vn_open(struct nameidata *ndp, int fmode, int cmode)
    135 {
    136 	struct vnode *vp;
    137 	struct lwp *l = curlwp;
    138 	kauth_cred_t cred = l->l_cred;
    139 	struct vattr va;
    140 	int error;
    141 	char *path;
    142 
    143 	ndp->ni_cnd.cn_flags &= TRYEMULROOT | NOCHROOT;
    144 
    145 	if (fmode & O_CREAT) {
    146 		ndp->ni_cnd.cn_nameiop = CREATE;
    147 		ndp->ni_cnd.cn_flags |= LOCKPARENT | LOCKLEAF;
    148 		if ((fmode & O_EXCL) == 0 &&
    149 		    ((fmode & O_NOFOLLOW) == 0))
    150 			ndp->ni_cnd.cn_flags |= FOLLOW;
    151 	} else {
    152 		ndp->ni_cnd.cn_nameiop = LOOKUP;
    153 		ndp->ni_cnd.cn_flags |= LOCKLEAF;
    154 		if ((fmode & O_NOFOLLOW) == 0)
    155 			ndp->ni_cnd.cn_flags |= FOLLOW;
    156 	}
    157 
    158 	VERIEXEC_PATH_GET(ndp->ni_dirp, ndp->ni_segflg, ndp->ni_dirp, path);
    159 
    160 	error = namei(ndp);
    161 	if (error)
    162 		goto out;
    163 
    164 	vp = ndp->ni_vp;
    165 
    166 #if NVERIEXEC > 0
    167 	error = veriexec_openchk(l, ndp->ni_vp, ndp->ni_dirp, fmode);
    168 	if (error)
    169 		goto bad;
    170 #endif /* NVERIEXEC > 0 */
    171 
    172 	if (fmode & O_CREAT) {
    173 		if (ndp->ni_vp == NULL) {
    174 			vattr_null(&va);
    175 			va.va_type = VREG;
    176 			va.va_mode = cmode;
    177 			if (fmode & O_EXCL)
    178 				 va.va_vaflags |= VA_EXCLUSIVE;
    179 			error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
    180 					   &ndp->ni_cnd, &va);
    181 			if (error)
    182 				goto out;
    183 			fmode &= ~O_TRUNC;
    184 			vp = ndp->ni_vp;
    185 		} else {
    186 			VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd);
    187 			if (ndp->ni_dvp == ndp->ni_vp)
    188 				vrele(ndp->ni_dvp);
    189 			else
    190 				vput(ndp->ni_dvp);
    191 			ndp->ni_dvp = NULL;
    192 			vp = ndp->ni_vp;
    193 			if (fmode & O_EXCL) {
    194 				error = EEXIST;
    195 				goto bad;
    196 			}
    197 			fmode &= ~O_CREAT;
    198 		}
    199 	} else {
    200 		vp = ndp->ni_vp;
    201 	}
    202 	if (vp->v_type == VSOCK) {
    203 		error = EOPNOTSUPP;
    204 		goto bad;
    205 	}
    206 	if (ndp->ni_vp->v_type == VLNK) {
    207 		error = EFTYPE;
    208 		goto bad;
    209 	}
    210 
    211 	if ((fmode & O_CREAT) == 0) {
    212 		error = vn_openchk(vp, cred, fmode);
    213 		if (error != 0)
    214 			goto bad;
    215 	}
    216 
    217 	if (fmode & O_TRUNC) {
    218 		VOP_UNLOCK(vp);			/* XXX */
    219 
    220 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);	/* XXX */
    221 		vattr_null(&va);
    222 		va.va_size = 0;
    223 		error = VOP_SETATTR(vp, &va, cred);
    224 		if (error != 0)
    225 			goto bad;
    226 	}
    227 	if ((error = VOP_OPEN(vp, fmode, cred)) != 0)
    228 		goto bad;
    229 	if (fmode & FWRITE) {
    230 		mutex_enter(&vp->v_interlock);
    231 		vp->v_writecount++;
    232 		mutex_exit(&vp->v_interlock);
    233 	}
    234 
    235 bad:
    236 	if (error)
    237 		vput(vp);
    238 out:
    239 	VERIEXEC_PATH_PUT(path);
    240 	return (error);
    241 }
    242 
    243 /*
    244  * Check for write permissions on the specified vnode.
    245  * Prototype text segments cannot be written.
    246  */
    247 int
    248 vn_writechk(struct vnode *vp)
    249 {
    250 
    251 	/*
    252 	 * If the vnode is in use as a process's text,
    253 	 * we can't allow writing.
    254 	 */
    255 	if (vp->v_iflag & VI_TEXT)
    256 		return (ETXTBSY);
    257 	return (0);
    258 }
    259 
    260 int
    261 vn_openchk(struct vnode *vp, kauth_cred_t cred, int fflags)
    262 {
    263 	int permbits = 0;
    264 	int error;
    265 
    266 	if ((fflags & FREAD) != 0) {
    267 		permbits = VREAD;
    268 	}
    269 	if ((fflags & (FWRITE | O_TRUNC)) != 0) {
    270 		permbits |= VWRITE;
    271 		if (vp->v_type == VDIR) {
    272 			error = EISDIR;
    273 			goto bad;
    274 		}
    275 		error = vn_writechk(vp);
    276 		if (error != 0)
    277 			goto bad;
    278 	}
    279 	error = VOP_ACCESS(vp, permbits, cred);
    280 bad:
    281 	return error;
    282 }
    283 
    284 /*
    285  * Mark a vnode as having executable mappings.
    286  */
    287 void
    288 vn_markexec(struct vnode *vp)
    289 {
    290 
    291 	if ((vp->v_iflag & VI_EXECMAP) != 0) {
    292 		/* Safe unlocked, as long as caller holds a reference. */
    293 		return;
    294 	}
    295 
    296 	mutex_enter(&vp->v_interlock);
    297 	if ((vp->v_iflag & VI_EXECMAP) == 0) {
    298 		atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages);
    299 		atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages);
    300 		vp->v_iflag |= VI_EXECMAP;
    301 	}
    302 	mutex_exit(&vp->v_interlock);
    303 }
    304 
    305 /*
    306  * Mark a vnode as being the text of a process.
    307  * Fail if the vnode is currently writable.
    308  */
    309 int
    310 vn_marktext(struct vnode *vp)
    311 {
    312 
    313 	if ((vp->v_iflag & (VI_TEXT|VI_EXECMAP)) == (VI_TEXT|VI_EXECMAP)) {
    314 		/* Safe unlocked, as long as caller holds a reference. */
    315 		return (0);
    316 	}
    317 
    318 	mutex_enter(&vp->v_interlock);
    319 	if (vp->v_writecount != 0) {
    320 		KASSERT((vp->v_iflag & VI_TEXT) == 0);
    321 		mutex_exit(&vp->v_interlock);
    322 		return (ETXTBSY);
    323 	}
    324 	if ((vp->v_iflag & VI_EXECMAP) == 0) {
    325 		atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages);
    326 		atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages);
    327 	}
    328 	vp->v_iflag |= (VI_TEXT | VI_EXECMAP);
    329 	mutex_exit(&vp->v_interlock);
    330 	return (0);
    331 }
    332 
    333 /*
    334  * Vnode close call
    335  *
    336  * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node.
    337  */
    338 int
    339 vn_close(struct vnode *vp, int flags, kauth_cred_t cred)
    340 {
    341 	int error;
    342 
    343 	if (flags & FWRITE) {
    344 		mutex_enter(&vp->v_interlock);
    345 		vp->v_writecount--;
    346 		mutex_exit(&vp->v_interlock);
    347 	}
    348 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
    349 	error = VOP_CLOSE(vp, flags, cred);
    350 	vput(vp);
    351 	return (error);
    352 }
    353 
    354 static int
    355 enforce_rlimit_fsize(struct vnode *vp, struct uio *uio, int ioflag)
    356 {
    357 	struct lwp *l = curlwp;
    358 	off_t testoff;
    359 
    360 	if (uio->uio_rw != UIO_WRITE || vp->v_type != VREG)
    361 		return 0;
    362 
    363 	KASSERT(VOP_ISLOCKED(vp) == LK_EXCLUSIVE);
    364 	if (ioflag & IO_APPEND)
    365 		testoff = vp->v_size;
    366 	else
    367 		testoff = uio->uio_offset;
    368 
    369 	if (testoff + uio->uio_resid >
    370 	    l->l_proc->p_rlimit[RLIMIT_FSIZE].rlim_cur) {
    371 		mutex_enter(proc_lock);
    372 		psignal(l->l_proc, SIGXFSZ);
    373 		mutex_exit(proc_lock);
    374 		return EFBIG;
    375 	}
    376 
    377 	return 0;
    378 }
    379 
    380 /*
    381  * Package up an I/O request on a vnode into a uio and do it.
    382  */
    383 int
    384 vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset,
    385     enum uio_seg segflg, int ioflg, kauth_cred_t cred, size_t *aresid,
    386     struct lwp *l)
    387 {
    388 	struct uio auio;
    389 	struct iovec aiov;
    390 	int error;
    391 
    392 	if ((ioflg & IO_NODELOCKED) == 0) {
    393 		if (rw == UIO_READ) {
    394 			vn_lock(vp, LK_SHARED | LK_RETRY);
    395 		} else /* UIO_WRITE */ {
    396 			vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
    397 		}
    398 	}
    399 	auio.uio_iov = &aiov;
    400 	auio.uio_iovcnt = 1;
    401 	aiov.iov_base = base;
    402 	aiov.iov_len = len;
    403 	auio.uio_resid = len;
    404 	auio.uio_offset = offset;
    405 	auio.uio_rw = rw;
    406 	if (segflg == UIO_SYSSPACE) {
    407 		UIO_SETUP_SYSSPACE(&auio);
    408 	} else {
    409 		auio.uio_vmspace = l->l_proc->p_vmspace;
    410 	}
    411 
    412 	if ((error = enforce_rlimit_fsize(vp, &auio, ioflg)) != 0)
    413 		goto out;
    414 
    415 	if (rw == UIO_READ) {
    416 		error = VOP_READ(vp, &auio, ioflg, cred);
    417 	} else {
    418 		error = VOP_WRITE(vp, &auio, ioflg, cred);
    419 	}
    420 
    421 	if (aresid)
    422 		*aresid = auio.uio_resid;
    423 	else
    424 		if (auio.uio_resid && error == 0)
    425 			error = EIO;
    426 
    427  out:
    428 	if ((ioflg & IO_NODELOCKED) == 0) {
    429 		VOP_UNLOCK(vp);
    430 	}
    431 	return (error);
    432 }
    433 
    434 int
    435 vn_readdir(file_t *fp, char *bf, int segflg, u_int count, int *done,
    436     struct lwp *l, off_t **cookies, int *ncookies)
    437 {
    438 	struct vnode *vp = (struct vnode *)fp->f_data;
    439 	struct iovec aiov;
    440 	struct uio auio;
    441 	int error, eofflag;
    442 
    443 	/* Limit the size on any kernel buffers used by VOP_READDIR */
    444 	count = min(MAXBSIZE, count);
    445 
    446 unionread:
    447 	if (vp->v_type != VDIR)
    448 		return (EINVAL);
    449 	aiov.iov_base = bf;
    450 	aiov.iov_len = count;
    451 	auio.uio_iov = &aiov;
    452 	auio.uio_iovcnt = 1;
    453 	auio.uio_rw = UIO_READ;
    454 	if (segflg == UIO_SYSSPACE) {
    455 		UIO_SETUP_SYSSPACE(&auio);
    456 	} else {
    457 		KASSERT(l == curlwp);
    458 		auio.uio_vmspace = l->l_proc->p_vmspace;
    459 	}
    460 	auio.uio_resid = count;
    461 	vn_lock(vp, LK_SHARED | LK_RETRY);
    462 	auio.uio_offset = fp->f_offset;
    463 	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies,
    464 		    ncookies);
    465 	mutex_enter(&fp->f_lock);
    466 	fp->f_offset = auio.uio_offset;
    467 	mutex_exit(&fp->f_lock);
    468 	VOP_UNLOCK(vp);
    469 	if (error)
    470 		return (error);
    471 
    472 	if (count == auio.uio_resid && vn_union_readdir_hook) {
    473 		struct vnode *ovp = vp;
    474 
    475 		error = (*vn_union_readdir_hook)(&vp, fp, l);
    476 		if (error)
    477 			return (error);
    478 		if (vp != ovp)
    479 			goto unionread;
    480 	}
    481 
    482 	if (count == auio.uio_resid && (vp->v_vflag & VV_ROOT) &&
    483 	    (vp->v_mount->mnt_flag & MNT_UNION)) {
    484 		struct vnode *tvp = vp;
    485 		vp = vp->v_mount->mnt_vnodecovered;
    486 		vref(vp);
    487 		mutex_enter(&fp->f_lock);
    488 		fp->f_data = vp;
    489 		fp->f_offset = 0;
    490 		mutex_exit(&fp->f_lock);
    491 		vrele(tvp);
    492 		goto unionread;
    493 	}
    494 	*done = count - auio.uio_resid;
    495 	return error;
    496 }
    497 
    498 /*
    499  * File table vnode read routine.
    500  */
    501 static int
    502 vn_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
    503     int flags)
    504 {
    505 	struct vnode *vp = (struct vnode *)fp->f_data;
    506 	int count, error, ioflag, fflag;
    507 
    508 	ioflag = IO_ADV_ENCODE(fp->f_advice);
    509 	fflag = fp->f_flag;
    510 	if (fflag & FNONBLOCK)
    511 		ioflag |= IO_NDELAY;
    512 	if ((fflag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC))
    513 		ioflag |= IO_SYNC;
    514 	if (fflag & FALTIO)
    515 		ioflag |= IO_ALTSEMANTICS;
    516 	if (fflag & FDIRECT)
    517 		ioflag |= IO_DIRECT;
    518 	vn_lock(vp, LK_SHARED | LK_RETRY);
    519 	uio->uio_offset = *offset;
    520 	count = uio->uio_resid;
    521 	error = VOP_READ(vp, uio, ioflag, cred);
    522 	if (flags & FOF_UPDATE_OFFSET)
    523 		*offset += count - uio->uio_resid;
    524 	VOP_UNLOCK(vp);
    525 	return (error);
    526 }
    527 
    528 /*
    529  * File table vnode write routine.
    530  */
    531 static int
    532 vn_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
    533     int flags)
    534 {
    535 	struct vnode *vp = (struct vnode *)fp->f_data;
    536 	int count, error, ioflag, fflag;
    537 
    538 	ioflag = IO_ADV_ENCODE(fp->f_advice) | IO_UNIT;
    539 	fflag = fp->f_flag;
    540 	if (vp->v_type == VREG && (fflag & O_APPEND))
    541 		ioflag |= IO_APPEND;
    542 	if (fflag & FNONBLOCK)
    543 		ioflag |= IO_NDELAY;
    544 	if (fflag & FFSYNC ||
    545 	    (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
    546 		ioflag |= IO_SYNC;
    547 	else if (fflag & FDSYNC)
    548 		ioflag |= IO_DSYNC;
    549 	if (fflag & FALTIO)
    550 		ioflag |= IO_ALTSEMANTICS;
    551 	if (fflag & FDIRECT)
    552 		ioflag |= IO_DIRECT;
    553 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
    554 	uio->uio_offset = *offset;
    555 	count = uio->uio_resid;
    556 
    557 	if ((error = enforce_rlimit_fsize(vp, uio, ioflag)) != 0)
    558 		goto out;
    559 
    560 	error = VOP_WRITE(vp, uio, ioflag, cred);
    561 
    562 	if (flags & FOF_UPDATE_OFFSET) {
    563 		if (ioflag & IO_APPEND) {
    564 			/*
    565 			 * SUSv3 describes behaviour for count = 0 as following:
    566 			 * "Before any action ... is taken, and if nbyte is zero
    567 			 * and the file is a regular file, the write() function
    568 			 * ... in the absence of errors ... shall return zero
    569 			 * and have no other results."
    570 			 */
    571 			if (count)
    572 				*offset = uio->uio_offset;
    573 		} else
    574 			*offset += count - uio->uio_resid;
    575 	}
    576 
    577  out:
    578 	VOP_UNLOCK(vp);
    579 	return (error);
    580 }
    581 
    582 /*
    583  * File table vnode stat routine.
    584  */
    585 static int
    586 vn_statfile(file_t *fp, struct stat *sb)
    587 {
    588 	struct vnode *vp = fp->f_data;
    589 	int error;
    590 
    591 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
    592 	error = vn_stat(vp, sb);
    593 	VOP_UNLOCK(vp);
    594 	return error;
    595 }
    596 
    597 int
    598 vn_stat(struct vnode *vp, struct stat *sb)
    599 {
    600 	struct vattr va;
    601 	int error;
    602 	mode_t mode;
    603 
    604 	memset(&va, 0, sizeof(va));
    605 	error = VOP_GETATTR(vp, &va, kauth_cred_get());
    606 	if (error)
    607 		return (error);
    608 	/*
    609 	 * Copy from vattr table
    610 	 */
    611 	sb->st_dev = va.va_fsid;
    612 	sb->st_ino = va.va_fileid;
    613 	mode = va.va_mode;
    614 	switch (vp->v_type) {
    615 	case VREG:
    616 		mode |= S_IFREG;
    617 		break;
    618 	case VDIR:
    619 		mode |= S_IFDIR;
    620 		break;
    621 	case VBLK:
    622 		mode |= S_IFBLK;
    623 		break;
    624 	case VCHR:
    625 		mode |= S_IFCHR;
    626 		break;
    627 	case VLNK:
    628 		mode |= S_IFLNK;
    629 		break;
    630 	case VSOCK:
    631 		mode |= S_IFSOCK;
    632 		break;
    633 	case VFIFO:
    634 		mode |= S_IFIFO;
    635 		break;
    636 	default:
    637 		return (EBADF);
    638 	};
    639 	sb->st_mode = mode;
    640 	sb->st_nlink = va.va_nlink;
    641 	sb->st_uid = va.va_uid;
    642 	sb->st_gid = va.va_gid;
    643 	sb->st_rdev = va.va_rdev;
    644 	sb->st_size = va.va_size;
    645 	sb->st_atimespec = va.va_atime;
    646 	sb->st_mtimespec = va.va_mtime;
    647 	sb->st_ctimespec = va.va_ctime;
    648 	sb->st_birthtimespec = va.va_birthtime;
    649 	sb->st_blksize = va.va_blocksize;
    650 	sb->st_flags = va.va_flags;
    651 	sb->st_gen = 0;
    652 	sb->st_blocks = va.va_bytes / S_BLKSIZE;
    653 	memset(sb->st_spare, 0, sizeof(sb->st_spare));
    654 	return (0);
    655 }
    656 
    657 /*
    658  * File table vnode fcntl routine.
    659  */
    660 static int
    661 vn_fcntl(file_t *fp, u_int com, void *data)
    662 {
    663 	struct vnode *vp = fp->f_data;
    664 	int error;
    665 
    666 	error = VOP_FCNTL(vp, com, data, fp->f_flag, kauth_cred_get());
    667 	return (error);
    668 }
    669 
    670 /*
    671  * File table vnode ioctl routine.
    672  */
    673 static int
    674 vn_ioctl(file_t *fp, u_long com, void *data)
    675 {
    676 	struct vnode *vp = fp->f_data, *ovp;
    677 	struct vattr vattr;
    678 	int error;
    679 
    680 	switch (vp->v_type) {
    681 
    682 	case VREG:
    683 	case VDIR:
    684 		if (com == FIONREAD) {
    685 			error = VOP_GETATTR(vp, &vattr,
    686 			    kauth_cred_get());
    687 			if (error)
    688 				return (error);
    689 			*(int *)data = vattr.va_size - fp->f_offset;
    690 			return (0);
    691 		}
    692 		if ((com == FIONWRITE) || (com == FIONSPACE)) {
    693 			/*
    694 			 * Files don't have send queues, so there never
    695 			 * are any bytes in them, nor is there any
    696 			 * open space in them.
    697 			 */
    698 			*(int *)data = 0;
    699 			return (0);
    700 		}
    701 		if (com == FIOGETBMAP) {
    702 			daddr_t *block;
    703 
    704 			if (*(daddr_t *)data < 0)
    705 				return (EINVAL);
    706 			block = (daddr_t *)data;
    707 			return (VOP_BMAP(vp, *block, NULL, block, NULL));
    708 		}
    709 		if (com == OFIOGETBMAP) {
    710 			daddr_t ibn, obn;
    711 
    712 			if (*(int32_t *)data < 0)
    713 				return (EINVAL);
    714 			ibn = (daddr_t)*(int32_t *)data;
    715 			error = VOP_BMAP(vp, ibn, NULL, &obn, NULL);
    716 			*(int32_t *)data = (int32_t)obn;
    717 			return error;
    718 		}
    719 		if (com == FIONBIO || com == FIOASYNC)	/* XXX */
    720 			return (0);			/* XXX */
    721 		/* fall into ... */
    722 	case VFIFO:
    723 	case VCHR:
    724 	case VBLK:
    725 		error = VOP_IOCTL(vp, com, data, fp->f_flag,
    726 		    kauth_cred_get());
    727 		if (error == 0 && com == TIOCSCTTY) {
    728 			vref(vp);
    729 			mutex_enter(proc_lock);
    730 			ovp = curproc->p_session->s_ttyvp;
    731 			curproc->p_session->s_ttyvp = vp;
    732 			mutex_exit(proc_lock);
    733 			if (ovp != NULL)
    734 				vrele(ovp);
    735 		}
    736 		return (error);
    737 
    738 	default:
    739 		return (EPASSTHROUGH);
    740 	}
    741 }
    742 
    743 /*
    744  * File table vnode poll routine.
    745  */
    746 static int
    747 vn_poll(file_t *fp, int events)
    748 {
    749 
    750 	return (VOP_POLL(fp->f_data, events));
    751 }
    752 
    753 /*
    754  * File table vnode kqfilter routine.
    755  */
    756 int
    757 vn_kqfilter(file_t *fp, struct knote *kn)
    758 {
    759 
    760 	return (VOP_KQFILTER(fp->f_data, kn));
    761 }
    762 
    763 /*
    764  * Check that the vnode is still valid, and if so
    765  * acquire requested lock.
    766  */
    767 int
    768 vn_lock(struct vnode *vp, int flags)
    769 {
    770 	int error;
    771 
    772 #if 0
    773 	KASSERT(vp->v_usecount > 0 || (vp->v_iflag & VI_ONWORKLST) != 0);
    774 #endif
    775 	KASSERT((flags & ~(LK_SHARED|LK_EXCLUSIVE|LK_NOWAIT|LK_RETRY)) == 0);
    776 	KASSERT(!mutex_owned(&vp->v_interlock));
    777 
    778 #ifdef DIAGNOSTIC
    779 	if (wapbl_vphaswapbl(vp))
    780 		WAPBL_JUNLOCK_ASSERT(wapbl_vptomp(vp));
    781 #endif
    782 
    783 	do {
    784 		/*
    785 		 * XXX PR 37706 forced unmount of file systems is unsafe.
    786 		 * Race between vclean() and this the remaining problem.
    787 		 */
    788 		mutex_enter(&vp->v_interlock);
    789 		if (vp->v_iflag & VI_XLOCK) {
    790 			if (flags & LK_NOWAIT) {
    791 				mutex_exit(&vp->v_interlock);
    792 				return EBUSY;
    793 			}
    794 			vwait(vp, VI_XLOCK);
    795 			mutex_exit(&vp->v_interlock);
    796 			error = ENOENT;
    797 		} else {
    798 			mutex_exit(&vp->v_interlock);
    799 			error = VOP_LOCK(vp, (flags & ~LK_RETRY));
    800 			if (error == 0 || error == EDEADLK || error == EBUSY)
    801 				return (error);
    802 		}
    803 	} while (flags & LK_RETRY);
    804 	return (error);
    805 }
    806 
    807 /*
    808  * File table vnode close routine.
    809  */
    810 static int
    811 vn_closefile(file_t *fp)
    812 {
    813 
    814 	return vn_close(fp->f_data, fp->f_flag, fp->f_cred);
    815 }
    816 
    817 /*
    818  * Simplified in-kernel wrapper calls for extended attribute access.
    819  * Both calls pass in a NULL credential, authorizing a "kernel" access.
    820  * Set IO_NODELOCKED in ioflg if the vnode is already locked.
    821  */
    822 int
    823 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
    824     const char *attrname, size_t *buflen, void *bf, struct lwp *l)
    825 {
    826 	struct uio auio;
    827 	struct iovec aiov;
    828 	int error;
    829 
    830 	aiov.iov_len = *buflen;
    831 	aiov.iov_base = bf;
    832 
    833 	auio.uio_iov = &aiov;
    834 	auio.uio_iovcnt = 1;
    835 	auio.uio_rw = UIO_READ;
    836 	auio.uio_offset = 0;
    837 	auio.uio_resid = *buflen;
    838 	UIO_SETUP_SYSSPACE(&auio);
    839 
    840 	if ((ioflg & IO_NODELOCKED) == 0)
    841 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
    842 
    843 	error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL);
    844 
    845 	if ((ioflg & IO_NODELOCKED) == 0)
    846 		VOP_UNLOCK(vp);
    847 
    848 	if (error == 0)
    849 		*buflen = *buflen - auio.uio_resid;
    850 
    851 	return (error);
    852 }
    853 
    854 /*
    855  * XXX Failure mode if partially written?
    856  */
    857 int
    858 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
    859     const char *attrname, size_t buflen, const void *bf, struct lwp *l)
    860 {
    861 	struct uio auio;
    862 	struct iovec aiov;
    863 	int error;
    864 
    865 	aiov.iov_len = buflen;
    866 	aiov.iov_base = __UNCONST(bf);		/* XXXUNCONST kills const */
    867 
    868 	auio.uio_iov = &aiov;
    869 	auio.uio_iovcnt = 1;
    870 	auio.uio_rw = UIO_WRITE;
    871 	auio.uio_offset = 0;
    872 	auio.uio_resid = buflen;
    873 	UIO_SETUP_SYSSPACE(&auio);
    874 
    875 	if ((ioflg & IO_NODELOCKED) == 0) {
    876 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
    877 	}
    878 
    879 	error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL);
    880 
    881 	if ((ioflg & IO_NODELOCKED) == 0) {
    882 		VOP_UNLOCK(vp);
    883 	}
    884 
    885 	return (error);
    886 }
    887 
    888 int
    889 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
    890     const char *attrname, struct lwp *l)
    891 {
    892 	int error;
    893 
    894 	if ((ioflg & IO_NODELOCKED) == 0) {
    895 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
    896 	}
    897 
    898 	error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL);
    899 	if (error == EOPNOTSUPP)
    900 		error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, NULL);
    901 
    902 	if ((ioflg & IO_NODELOCKED) == 0) {
    903 		VOP_UNLOCK(vp);
    904 	}
    905 
    906 	return (error);
    907 }
    908 
    909 void
    910 vn_ra_allocctx(struct vnode *vp)
    911 {
    912 	struct uvm_ractx *ra = NULL;
    913 
    914 	KASSERT(mutex_owned(&vp->v_interlock));
    915 
    916 	if (vp->v_type != VREG) {
    917 		return;
    918 	}
    919 	if (vp->v_ractx != NULL) {
    920 		return;
    921 	}
    922 	if (vp->v_ractx == NULL) {
    923 		mutex_exit(&vp->v_interlock);
    924 		ra = uvm_ra_allocctx();
    925 		mutex_enter(&vp->v_interlock);
    926 		if (ra != NULL && vp->v_ractx == NULL) {
    927 			vp->v_ractx = ra;
    928 			ra = NULL;
    929 		}
    930 	}
    931 	if (ra != NULL) {
    932 		uvm_ra_freectx(ra);
    933 	}
    934 }
    935 
    936 int
    937 vn_fifo_bypass(void *v)
    938 {
    939 	struct vop_generic_args *ap = v;
    940 
    941 	return VOCALL(fifo_vnodeop_p, ap->a_desc->vdesc_offset, v);
    942 }
    943