smbfs_io.c revision 95314
1/*
2 * Copyright (c) 2000-2001, Boris Popov
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *    This product includes software developed by Boris Popov.
16 * 4. Neither the name of the author nor the names of any co-contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * $FreeBSD: head/sys/fs/smbfs/smbfs_io.c 95314 2002-04-23 13:55:14Z bp $
33 *
34 */
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/resourcevar.h>	/* defines plimit structure in proc struct */
38#include <sys/kernel.h>
39#include <sys/proc.h>
40#include <sys/fcntl.h>
41#include <sys/bio.h>
42#include <sys/buf.h>
43#include <sys/mount.h>
44#include <sys/namei.h>
45#include <sys/vnode.h>
46#include <sys/dirent.h>
47#include <sys/signalvar.h>
48#include <sys/sysctl.h>
49#include <sys/vmmeter.h>
50
51#include <vm/vm.h>
52#include <vm/vm_page.h>
53#include <vm/vm_extern.h>
54#include <vm/vm_object.h>
55#include <vm/vm_pager.h>
56#include <vm/vnode_pager.h>
57/*
58#include <sys/ioccom.h>
59*/
60#include <netsmb/smb.h>
61#include <netsmb/smb_conn.h>
62#include <netsmb/smb_subr.h>
63
64#include <fs/smbfs/smbfs.h>
65#include <fs/smbfs/smbfs_node.h>
66#include <fs/smbfs/smbfs_subr.h>
67
68/*#define SMBFS_RWGENERIC*/
69
70extern int smbfs_pbuf_freecnt;
71
72static int smbfs_fastlookup = 1;
73
74SYSCTL_DECL(_vfs_smbfs);
75SYSCTL_INT(_vfs_smbfs, OID_AUTO, fastlookup, CTLFLAG_RW, &smbfs_fastlookup, 0, "");
76
77
78#define DE_SIZE	(sizeof(struct dirent))
79
80static int
81smbfs_readvdir(struct vnode *vp, struct uio *uio, struct ucred *cred)
82{
83	struct dirent de;
84	struct componentname cn;
85	struct smb_cred scred;
86	struct smbfs_fctx *ctx;
87	struct vnode *newvp;
88	struct smbnode *np = VTOSMB(vp);
89	int error/*, *eofflag = ap->a_eofflag*/;
90	long offset, limit;
91
92	np = VTOSMB(vp);
93	SMBVDEBUG("dirname='%s'\n", np->n_name);
94	smb_makescred(&scred, uio->uio_td, cred);
95	offset = uio->uio_offset / DE_SIZE; 	/* offset in the directory */
96	limit = uio->uio_resid / DE_SIZE;
97	if (uio->uio_resid < DE_SIZE || uio->uio_offset < 0)
98		return EINVAL;
99	while (limit && offset < 2) {
100		limit--;
101		bzero((caddr_t)&de, DE_SIZE);
102		de.d_reclen = DE_SIZE;
103		de.d_fileno = (offset == 0) ? np->n_ino :
104		    (np->n_parent ? np->n_parent->n_ino : 2);
105		if (de.d_fileno == 0)
106			de.d_fileno = 0x7ffffffd + offset;
107		de.d_namlen = offset + 1;
108		de.d_name[0] = '.';
109		de.d_name[1] = '.';
110		de.d_name[offset + 1] = '\0';
111		de.d_type = DT_DIR;
112		error = uiomove((caddr_t)&de, DE_SIZE, uio);
113		if (error)
114			return error;
115		offset++;
116		uio->uio_offset += DE_SIZE;
117	}
118	if (limit == 0)
119		return 0;
120	if (offset != np->n_dirofs || np->n_dirseq == NULL) {
121		SMBVDEBUG("Reopening search %ld:%ld\n", offset, np->n_dirofs);
122		if (np->n_dirseq) {
123			smbfs_findclose(np->n_dirseq, &scred);
124			np->n_dirseq = NULL;
125		}
126		np->n_dirofs = 2;
127		error = smbfs_findopen(np, "*", 1,
128		    SMB_FA_SYSTEM | SMB_FA_HIDDEN | SMB_FA_DIR,
129		    &scred, &ctx);
130		if (error) {
131			SMBVDEBUG("can not open search, error = %d", error);
132			return error;
133		}
134		np->n_dirseq = ctx;
135	} else
136		ctx = np->n_dirseq;
137	while (np->n_dirofs < offset) {
138		error = smbfs_findnext(ctx, offset - np->n_dirofs++, &scred);
139		if (error) {
140			smbfs_findclose(np->n_dirseq, &scred);
141			np->n_dirseq = NULL;
142			return error == ENOENT ? 0 : error;
143		}
144	}
145	error = 0;
146	for (; limit; limit--, offset++) {
147		error = smbfs_findnext(ctx, limit, &scred);
148		if (error)
149			break;
150		np->n_dirofs++;
151		bzero((caddr_t)&de, DE_SIZE);
152		de.d_reclen = DE_SIZE;
153		de.d_fileno = ctx->f_attr.fa_ino;
154		de.d_type = (ctx->f_attr.fa_attr & SMB_FA_DIR) ? DT_DIR : DT_REG;
155		de.d_namlen = ctx->f_nmlen;
156		bcopy(ctx->f_name, de.d_name, de.d_namlen);
157		de.d_name[de.d_namlen] = '\0';
158		if (smbfs_fastlookup) {
159			error = smbfs_nget(vp->v_mount, vp, ctx->f_name,
160			    ctx->f_nmlen, &ctx->f_attr, &newvp);
161			if (!error) {
162				cn.cn_nameptr = de.d_name;
163				cn.cn_namelen = de.d_namlen;
164		    		cache_enter(vp, newvp, &cn);
165				vput(newvp);
166			}
167		}
168		error = uiomove((caddr_t)&de, DE_SIZE, uio);
169		if (error)
170			break;
171	}
172	if (error == ENOENT)
173		error = 0;
174	uio->uio_offset = offset * DE_SIZE;
175	return error;
176}
177
178int
179smbfs_readvnode(struct vnode *vp, struct uio *uiop, struct ucred *cred)
180{
181	struct smbmount *smp = VFSTOSMBFS(vp->v_mount);
182	struct smbnode *np = VTOSMB(vp);
183	struct thread *td;
184	struct vattr vattr;
185	struct smb_cred scred;
186	int error, lks;
187
188	if (vp->v_type != VREG && vp->v_type != VDIR) {
189		SMBFSERR("vn types other than VREG or VDIR are unsupported !\n");
190		return EIO;
191	}
192	if (uiop->uio_resid == 0)
193		return 0;
194	if (uiop->uio_offset < 0)
195		return EINVAL;
196/*	if (uiop->uio_offset + uiop->uio_resid > smp->nm_maxfilesize)
197		return EFBIG;*/
198	td = uiop->uio_td;
199	if (vp->v_type == VDIR) {
200		lks = LK_EXCLUSIVE;/*lockstatus(&vp->v_lock, td);*/
201		if (lks == LK_SHARED)
202			vn_lock(vp, LK_UPGRADE | LK_RETRY, td);
203		error = smbfs_readvdir(vp, uiop, cred);
204		if (lks == LK_SHARED)
205			vn_lock(vp, LK_DOWNGRADE | LK_RETRY, td);
206		return error;
207	}
208
209/*	biosize = SSTOCN(smp->sm_share)->sc_txmax;*/
210	if (np->n_flag & NMODIFIED) {
211		smbfs_attr_cacheremove(vp);
212		error = VOP_GETATTR(vp, &vattr, cred, td);
213		if (error)
214			return error;
215		np->n_mtime.tv_sec = vattr.va_mtime.tv_sec;
216	} else {
217		error = VOP_GETATTR(vp, &vattr, cred, td);
218		if (error)
219			return error;
220		if (np->n_mtime.tv_sec != vattr.va_mtime.tv_sec) {
221			error = smbfs_vinvalbuf(vp, V_SAVE, cred, td, 1);
222			if (error)
223				return error;
224			np->n_mtime.tv_sec = vattr.va_mtime.tv_sec;
225		}
226	}
227	smb_makescred(&scred, td, cred);
228	return smb_read(smp->sm_share, np->n_fid, uiop, &scred);
229}
230
231int
232smbfs_writevnode(struct vnode *vp, struct uio *uiop,
233	struct ucred *cred, int ioflag)
234{
235	struct smbmount *smp = VTOSMBFS(vp);
236	struct smbnode *np = VTOSMB(vp);
237	struct smb_cred scred;
238	struct proc *p;
239	struct thread *td;
240	int error = 0;
241
242	if (vp->v_type != VREG) {
243		SMBERROR("vn types other than VREG unsupported !\n");
244		return EIO;
245	}
246	SMBVDEBUG("ofs=%d,resid=%d\n",(int)uiop->uio_offset, uiop->uio_resid);
247	if (uiop->uio_offset < 0)
248		return EINVAL;
249/*	if (uiop->uio_offset + uiop->uio_resid > smp->nm_maxfilesize)
250		return (EFBIG);*/
251	td = uiop->uio_td;
252	p = td->td_proc;
253	if (ioflag & (IO_APPEND | IO_SYNC)) {
254		if (np->n_flag & NMODIFIED) {
255			smbfs_attr_cacheremove(vp);
256			error = smbfs_vinvalbuf(vp, V_SAVE, cred, td, 1);
257			if (error)
258				return error;
259		}
260		if (ioflag & IO_APPEND) {
261#if notyet
262			/*
263			 * File size can be changed by another client
264			 */
265			smbfs_attr_cacheremove(vp);
266			error = VOP_GETATTR(vp, &vattr, cred, td);
267			if (error) return (error);
268#endif
269			uiop->uio_offset = np->n_size;
270		}
271	}
272	if (uiop->uio_resid == 0)
273		return 0;
274	if (p && uiop->uio_offset + uiop->uio_resid > p->p_rlimit[RLIMIT_FSIZE].rlim_cur) {
275		PROC_LOCK(td->td_proc);
276		psignal(td->td_proc, SIGXFSZ);
277		PROC_UNLOCK(td->td_proc);
278		return EFBIG;
279	}
280	smb_makescred(&scred, td, cred);
281	error = smb_write(smp->sm_share, np->n_fid, uiop, &scred);
282	SMBVDEBUG("after: ofs=%d,resid=%d\n",(int)uiop->uio_offset, uiop->uio_resid);
283	if (!error) {
284		if (uiop->uio_offset > np->n_size) {
285			np->n_size = uiop->uio_offset;
286			vnode_pager_setsize(vp, np->n_size);
287		}
288	}
289	return error;
290}
291
292/*
293 * Do an I/O operation to/from a cache block.
294 */
295int
296smbfs_doio(struct buf *bp, struct ucred *cr, struct thread *td)
297{
298	struct vnode *vp = bp->b_vp;
299	struct smbmount *smp = VFSTOSMBFS(vp->v_mount);
300	struct smbnode *np = VTOSMB(vp);
301	struct uio uio, *uiop = &uio;
302	struct iovec io;
303	struct smb_cred scred;
304	int error = 0;
305
306	uiop->uio_iov = &io;
307	uiop->uio_iovcnt = 1;
308	uiop->uio_segflg = UIO_SYSSPACE;
309	uiop->uio_td = td;
310
311	smb_makescred(&scred, td, cr);
312
313	if (bp->b_iocmd == BIO_READ) {
314	    io.iov_len = uiop->uio_resid = bp->b_bcount;
315	    io.iov_base = bp->b_data;
316	    uiop->uio_rw = UIO_READ;
317	    switch (vp->v_type) {
318	      case VREG:
319		uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE;
320		error = smb_read(smp->sm_share, np->n_fid, uiop, &scred);
321		if (error)
322			break;
323		if (uiop->uio_resid) {
324			int left = uiop->uio_resid;
325			int nread = bp->b_bcount - left;
326			if (left > 0)
327			    bzero((char *)bp->b_data + nread, left);
328		}
329		break;
330	    default:
331		printf("smbfs_doio:  type %x unexpected\n",vp->v_type);
332		break;
333	    };
334	    if (error) {
335		bp->b_error = error;
336		bp->b_ioflags |= BIO_ERROR;
337	    }
338	} else { /* write */
339	    if (((bp->b_blkno * DEV_BSIZE) + bp->b_dirtyend) > np->n_size)
340		bp->b_dirtyend = np->n_size - (bp->b_blkno * DEV_BSIZE);
341
342	    if (bp->b_dirtyend > bp->b_dirtyoff) {
343		io.iov_len = uiop->uio_resid = bp->b_dirtyend - bp->b_dirtyoff;
344		uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff;
345		io.iov_base = (char *)bp->b_data + bp->b_dirtyoff;
346		uiop->uio_rw = UIO_WRITE;
347		bp->b_flags |= B_WRITEINPROG;
348		error = smb_write(smp->sm_share, np->n_fid, uiop, &scred);
349		bp->b_flags &= ~B_WRITEINPROG;
350
351		/*
352		 * For an interrupted write, the buffer is still valid
353		 * and the write hasn't been pushed to the server yet,
354		 * so we can't set BIO_ERROR and report the interruption
355		 * by setting B_EINTR. For the B_ASYNC case, B_EINTR
356		 * is not relevant, so the rpc attempt is essentially
357		 * a noop.  For the case of a V3 write rpc not being
358		 * committed to stable storage, the block is still
359		 * dirty and requires either a commit rpc or another
360		 * write rpc with iomode == NFSV3WRITE_FILESYNC before
361		 * the block is reused. This is indicated by setting
362		 * the B_DELWRI and B_NEEDCOMMIT flags.
363		 */
364    		if (error == EINTR
365		    || (!error && (bp->b_flags & B_NEEDCOMMIT))) {
366			int s;
367
368			s = splbio();
369			bp->b_flags &= ~(B_INVAL|B_NOCACHE);
370			if ((bp->b_flags & B_ASYNC) == 0)
371			    bp->b_flags |= B_EINTR;
372			if ((bp->b_flags & B_PAGING) == 0) {
373			    bdirty(bp);
374			    bp->b_flags &= ~B_DONE;
375			}
376			if ((bp->b_flags & B_ASYNC) == 0)
377			    bp->b_flags |= B_EINTR;
378			splx(s);
379	    	} else {
380			if (error) {
381				bp->b_ioflags |= BIO_ERROR;
382				bp->b_error = error;
383			}
384			bp->b_dirtyoff = bp->b_dirtyend = 0;
385		}
386	    } else {
387		bp->b_resid = 0;
388		bufdone(bp);
389		return 0;
390	    }
391	}
392	bp->b_resid = uiop->uio_resid;
393	bufdone(bp);
394	return error;
395}
396
397/*
398 * Vnode op for VM getpages.
399 * Wish wish .... get rid from multiple IO routines
400 */
401int
402smbfs_getpages(ap)
403	struct vop_getpages_args /* {
404		struct vnode *a_vp;
405		vm_page_t *a_m;
406		int a_count;
407		int a_reqpage;
408		vm_ooffset_t a_offset;
409	} */ *ap;
410{
411#ifdef SMBFS_RWGENERIC
412	return vop_stdgetpages(ap);
413#else
414	int i, error, nextoff, size, toff, npages, count;
415	struct uio uio;
416	struct iovec iov;
417	vm_offset_t kva;
418	struct buf *bp;
419	struct vnode *vp;
420	struct thread *td;
421	struct ucred *cred;
422	struct smbmount *smp;
423	struct smbnode *np;
424	struct smb_cred scred;
425	vm_page_t *pages;
426
427	vp = ap->a_vp;
428	td = curthread;				/* XXX */
429	cred = td->td_ucred;		/* XXX */
430	np = VTOSMB(vp);
431	smp = VFSTOSMBFS(vp->v_mount);
432	pages = ap->a_m;
433	count = ap->a_count;
434
435	if (vp->v_object == NULL) {
436		printf("smbfs_getpages: called with non-merged cache vnode??\n");
437		return VM_PAGER_ERROR;
438	}
439	smb_makescred(&scred, td, cred);
440
441	bp = getpbuf(&smbfs_pbuf_freecnt);
442
443	npages = btoc(count);
444	kva = (vm_offset_t) bp->b_data;
445	pmap_qenter(kva, pages, npages);
446	cnt.v_vnodein++;
447	cnt.v_vnodepgsin += count;
448
449	iov.iov_base = (caddr_t) kva;
450	iov.iov_len = count;
451	uio.uio_iov = &iov;
452	uio.uio_iovcnt = 1;
453	uio.uio_offset = IDX_TO_OFF(pages[0]->pindex);
454	uio.uio_resid = count;
455	uio.uio_segflg = UIO_SYSSPACE;
456	uio.uio_rw = UIO_READ;
457	uio.uio_td = td;
458
459	error = smb_read(smp->sm_share, np->n_fid, &uio, &scred);
460	pmap_qremove(kva, npages);
461
462	relpbuf(bp, &smbfs_pbuf_freecnt);
463
464	if (error && (uio.uio_resid == count)) {
465		printf("smbfs_getpages: error %d\n",error);
466		for (i = 0; i < npages; i++) {
467			if (ap->a_reqpage != i)
468				vm_page_free(pages[i]);
469		}
470		return VM_PAGER_ERROR;
471	}
472
473	size = count - uio.uio_resid;
474
475	for (i = 0, toff = 0; i < npages; i++, toff = nextoff) {
476		vm_page_t m;
477		nextoff = toff + PAGE_SIZE;
478		m = pages[i];
479
480		m->flags &= ~PG_ZERO;
481
482		if (nextoff <= size) {
483			m->valid = VM_PAGE_BITS_ALL;
484			vm_page_undirty(m);
485		} else {
486			int nvalid = ((size + DEV_BSIZE - 1) - toff) & ~(DEV_BSIZE - 1);
487			vm_page_set_validclean(m, 0, nvalid);
488		}
489
490		if (i != ap->a_reqpage) {
491			/*
492			 * Whether or not to leave the page activated is up in
493			 * the air, but we should put the page on a page queue
494			 * somewhere (it already is in the object).  Result:
495			 * It appears that emperical results show that
496			 * deactivating pages is best.
497			 */
498
499			/*
500			 * Just in case someone was asking for this page we
501			 * now tell them that it is ok to use.
502			 */
503			if (!error) {
504				if (m->flags & PG_WANTED)
505					vm_page_activate(m);
506				else
507					vm_page_deactivate(m);
508				vm_page_wakeup(m);
509			} else {
510				vm_page_free(m);
511			}
512		}
513	}
514	return 0;
515#endif /* SMBFS_RWGENERIC */
516}
517
518/*
519 * Vnode op for VM putpages.
520 * possible bug: all IO done in sync mode
521 * Note that vop_close always invalidate pages before close, so it's
522 * not necessary to open vnode.
523 */
524int
525smbfs_putpages(ap)
526	struct vop_putpages_args /* {
527		struct vnode *a_vp;
528		vm_page_t *a_m;
529		int a_count;
530		int a_sync;
531		int *a_rtvals;
532		vm_ooffset_t a_offset;
533	} */ *ap;
534{
535	int error;
536	struct vnode *vp = ap->a_vp;
537	struct thread *td;
538	struct ucred *cred;
539
540#ifdef SMBFS_RWGENERIC
541	td = curthread;			/* XXX */
542	cred = td->td_ucred;		/* XXX */
543	VOP_OPEN(vp, FWRITE, cred, td);
544	error = vop_stdputpages(ap);
545	VOP_CLOSE(vp, FWRITE, cred, td);
546	return error;
547#else
548	struct uio uio;
549	struct iovec iov;
550	vm_offset_t kva;
551	struct buf *bp;
552	int i, npages, count;
553	int *rtvals;
554	struct smbmount *smp;
555	struct smbnode *np;
556	struct smb_cred scred;
557	vm_page_t *pages;
558
559	td = curthread;			/* XXX */
560	cred = td->td_ucred;		/* XXX */
561/*	VOP_OPEN(vp, FWRITE, cred, td);*/
562	np = VTOSMB(vp);
563	smp = VFSTOSMBFS(vp->v_mount);
564	pages = ap->a_m;
565	count = ap->a_count;
566	rtvals = ap->a_rtvals;
567	npages = btoc(count);
568
569	for (i = 0; i < npages; i++) {
570		rtvals[i] = VM_PAGER_AGAIN;
571	}
572
573	bp = getpbuf(&smbfs_pbuf_freecnt);
574
575	kva = (vm_offset_t) bp->b_data;
576	pmap_qenter(kva, pages, npages);
577	cnt.v_vnodeout++;
578	cnt.v_vnodepgsout += count;
579
580	iov.iov_base = (caddr_t) kva;
581	iov.iov_len = count;
582	uio.uio_iov = &iov;
583	uio.uio_iovcnt = 1;
584	uio.uio_offset = IDX_TO_OFF(pages[0]->pindex);
585	uio.uio_resid = count;
586	uio.uio_segflg = UIO_SYSSPACE;
587	uio.uio_rw = UIO_WRITE;
588	uio.uio_td = td;
589	SMBVDEBUG("ofs=%d,resid=%d\n",(int)uio.uio_offset, uio.uio_resid);
590
591	smb_makescred(&scred, td, cred);
592	error = smb_write(smp->sm_share, np->n_fid, &uio, &scred);
593/*	VOP_CLOSE(vp, FWRITE, cred, td);*/
594	SMBVDEBUG("paged write done: %d\n", error);
595
596	pmap_qremove(kva, npages);
597
598	relpbuf(bp, &smbfs_pbuf_freecnt);
599
600	if (!error) {
601		int nwritten = round_page(count - uio.uio_resid) / PAGE_SIZE;
602		for (i = 0; i < nwritten; i++) {
603			rtvals[i] = VM_PAGER_OK;
604			vm_page_undirty(pages[i]);
605		}
606	}
607	return rtvals[0];
608#endif /* SMBFS_RWGENERIC */
609}
610
611/*
612 * Flush and invalidate all dirty buffers. If another process is already
613 * doing the flush, just wait for completion.
614 */
615int
616smbfs_vinvalbuf(vp, flags, cred, td, intrflg)
617	struct vnode *vp;
618	int flags;
619	struct ucred *cred;
620	struct thread *td;
621	int intrflg;
622{
623	struct smbnode *np = VTOSMB(vp);
624	int error = 0, slpflag, slptimeo;
625
626	if (vp->v_flag & VXLOCK)
627		return 0;
628	if (intrflg) {
629		slpflag = PCATCH;
630		slptimeo = 2 * hz;
631	} else {
632		slpflag = 0;
633		slptimeo = 0;
634	}
635	while (np->n_flag & NFLUSHINPROG) {
636		np->n_flag |= NFLUSHWANT;
637		error = tsleep((caddr_t)&np->n_flag, PRIBIO + 2, "smfsvinv", slptimeo);
638		error = smb_proc_intr(td->td_proc);
639		if (error == EINTR && intrflg)
640			return EINTR;
641	}
642	np->n_flag |= NFLUSHINPROG;
643	error = vinvalbuf(vp, flags, cred, td, slpflag, 0);
644	while (error) {
645		if (intrflg && (error == ERESTART || error == EINTR)) {
646			np->n_flag &= ~NFLUSHINPROG;
647			if (np->n_flag & NFLUSHWANT) {
648				np->n_flag &= ~NFLUSHWANT;
649				wakeup((caddr_t)&np->n_flag);
650			}
651			return EINTR;
652		}
653		error = vinvalbuf(vp, flags, cred, td, slpflag, 0);
654	}
655	np->n_flag &= ~(NMODIFIED | NFLUSHINPROG);
656	if (np->n_flag & NFLUSHWANT) {
657		np->n_flag &= ~NFLUSHWANT;
658		wakeup((caddr_t)&np->n_flag);
659	}
660	return (error);
661}
662