Import kernel part of SMB/CIFS requester.

Add smbfs(CIFS) filesystem.

Userland part will be in the ports tree for a while.

Obtained from:	smbfs-1.3.7-dev package.

1 files changed, 672 insertions, 0 deletions

diff --git a/sys/fs/smbfs/smbfs_io.c b/sys/fs/smbfs/smbfs_io.c
new file mode 100644
index 0000000..b275d74
--- /dev/null
+++ b/sys/fs/smbfs/smbfs_io.c
@@ -0,0 +1,672 @@
+/*
+ * Copyright (c) 2000-2001, Boris Popov
+ * 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 Boris Popov.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ * $FreeBSD$
+ *
+ */
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/resourcevar.h>	/* defines plimit structure in proc struct */
+#include <sys/kernel.h>
+#include <sys/proc.h>
+#include <sys/fcntl.h>
+#include <sys/bio.h>
+#include <sys/buf.h>
+#include <sys/mount.h>
+#include <sys/namei.h>
+#include <sys/vnode.h>
+#include <sys/dirent.h>
+#include <sys/signalvar.h>
+#include <sys/sysctl.h>
+
+#include <vm/vm.h>
+#if __FreeBSD_version < 400000
+#include <vm/vm_prot.h>
+#endif
+#include <vm/vm_page.h>
+#include <vm/vm_extern.h>
+#include <vm/vm_object.h>
+#include <vm/vm_pager.h>
+#include <vm/vnode_pager.h>
+/*
+#include <sys/ioccom.h>
+*/
+#include <netsmb/smb.h>
+#include <netsmb/smb_conn.h>
+#include <netsmb/smb_subr.h>
+
+#include <fs/smbfs/smbfs.h>
+#include <fs/smbfs/smbfs_node.h>
+#include <fs/smbfs/smbfs_subr.h>
+
+/*#define SMBFS_RWGENERIC*/
+
+extern int smbfs_pbuf_freecnt;
+
+static int smbfs_fastlookup = 1;
+
+extern struct linker_set sysctl_vfs_smbfs;
+
+SYSCTL_DECL(_vfs_smbfs);
+SYSCTL_INT(_vfs_smbfs, OID_AUTO, fastlookup, CTLFLAG_RW, &smbfs_fastlookup, 0, "");
+
+
+#define DE_SIZE	(sizeof(struct dirent))
+
+static int
+smbfs_readvdir(struct vnode *vp, struct uio *uio, struct ucred *cred)
+{
+	struct dirent de;
+	struct componentname cn;
+	struct smb_cred scred;
+	struct smbfs_fctx *ctx;
+	struct vnode *newvp;
+	struct smbnode *np = VTOSMB(vp);
+	int error/*, *eofflag = ap->a_eofflag*/;
+	long offset, limit;
+
+	np = VTOSMB(vp);
+	SMBVDEBUG("dirname='%s'\n", np->n_name);
+	smb_makescred(&scred, uio->uio_procp, cred);
+	offset = uio->uio_offset / DE_SIZE; 	/* offset in the directory */
+	limit = uio->uio_resid / DE_SIZE;
+	if (uio->uio_resid < DE_SIZE || uio->uio_offset < 0)
+		return EINVAL;
+	while (limit && offset < 2) {
+		limit--;
+		bzero((caddr_t)&de, DE_SIZE);
+		de.d_reclen = DE_SIZE;
+		de.d_fileno = (offset == 0) ? np->n_ino :
+		    (np->n_parent ? np->n_parent->n_ino : 2);
+		if (de.d_fileno == 0)
+			de.d_fileno = 0x7ffffffd + offset;
+		de.d_namlen = offset + 1;
+		de.d_name[0] = '.';
+		de.d_name[1] = '.';
+		de.d_name[offset + 1] = '\0';
+		de.d_type = DT_DIR;
+		error = uiomove((caddr_t)&de, DE_SIZE, uio);
+		if (error)
+			return error;
+		offset++;
+		uio->uio_offset += DE_SIZE;
+	}
+	if (limit == 0)
+		return 0;
+	if (offset != np->n_dirofs || np->n_dirseq == NULL) {
+		SMBVDEBUG("Reopening search %ld:%ld\n", offset, np->n_dirofs);
+		if (np->n_dirseq) {
+			smbfs_findclose(np->n_dirseq, &scred);
+			np->n_dirseq = NULL;
+		}
+		np->n_dirofs = 2;
+		error = smbfs_findopen(np, "*", 1,
+		    SMB_FA_SYSTEM | SMB_FA_HIDDEN | SMB_FA_DIR,
+		    &scred, &ctx);
+		if (error) {
+			SMBVDEBUG("can not open search, error = %d", error);
+			return error;
+		}
+		np->n_dirseq = ctx;
+	} else
+		ctx = np->n_dirseq;
+	while (np->n_dirofs < offset) {
+		error = smbfs_findnext(ctx, offset - np->n_dirofs++, &scred);
+		if (error) {
+			smbfs_findclose(np->n_dirseq, &scred);
+			np->n_dirseq = NULL;
+			return error == ENOENT ? 0 : error;
+		}
+	}
+	error = 0;
+	for (; limit; limit--, offset++) {
+		error = smbfs_findnext(ctx, limit, &scred);
+		if (error)
+			break;
+		np->n_dirofs++;
+		bzero((caddr_t)&de, DE_SIZE);
+		de.d_reclen = DE_SIZE;
+		de.d_fileno = ctx->f_attr.fa_ino;
+		de.d_type = (ctx->f_attr.fa_attr & SMB_FA_DIR) ? DT_DIR : DT_REG;
+		de.d_namlen = ctx->f_nmlen;
+		bcopy(ctx->f_name, de.d_name, de.d_namlen);
+		de.d_name[de.d_namlen] = '\0';
+		if (smbfs_fastlookup) {
+			error = smbfs_nget(vp->v_mount, vp, ctx->f_name,
+			    ctx->f_nmlen, &ctx->f_attr, &newvp);
+			if (!error) {
+				cn.cn_nameptr = de.d_name;
+				cn.cn_namelen = de.d_namlen;
+		    		cache_enter(vp, newvp, &cn);
+				vput(newvp);
+			}
+		}
+		error = uiomove((caddr_t)&de, DE_SIZE, uio);
+		if (error)
+			break;
+	}
+	if (error == ENOENT)
+		error = 0;
+	uio->uio_offset = offset * DE_SIZE;
+	return error;
+}
+
+int
+smbfs_readvnode(struct vnode *vp, struct uio *uiop, struct ucred *cred)
+{
+	struct smbmount *smp = VFSTOSMBFS(vp->v_mount);
+	struct smbnode *np = VTOSMB(vp);
+	struct proc *p;
+	struct vattr vattr;
+	struct smb_cred scred;
+	int error, lks;
+
+	if (vp->v_type != VREG && vp->v_type != VDIR) {
+		SMBFSERR("vn types other than VREG or VDIR are unsupported !\n");
+		return EIO;
+	}
+	if (uiop->uio_resid == 0)
+		return 0;
+	if (uiop->uio_offset < 0)
+		return EINVAL;
+/*	if (uiop->uio_offset + uiop->uio_resid > smp->nm_maxfilesize)
+		return EFBIG;*/
+	p = uiop->uio_procp;
+	if (vp->v_type == VDIR) {
+		lks = LK_EXCLUSIVE;/*lockstatus(&vp->v_lock, p);*/
+		if (lks == LK_SHARED)
+			vn_lock(vp, LK_UPGRADE | LK_RETRY, p);
+		error = smbfs_readvdir(vp, uiop, cred);
+		if (lks == LK_SHARED)
+			vn_lock(vp, LK_DOWNGRADE | LK_RETRY, p);
+		return error;
+	}
+
+/*	biosize = SSTOCN(smp->sm_share)->sc_txmax;*/
+	if (np->n_flag & NMODIFIED) {
+		smbfs_attr_cacheremove(vp);
+		error = VOP_GETATTR(vp, &vattr, cred, p);
+		if (error)
+			return error;
+		np->n_mtime.tv_sec = vattr.va_mtime.tv_sec;
+	} else {
+		error = VOP_GETATTR(vp, &vattr, cred, p);
+		if (error)
+			return error;
+		if (np->n_mtime.tv_sec != vattr.va_mtime.tv_sec) {
+			error = smbfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+			if (error)
+				return error;
+			np->n_mtime.tv_sec = vattr.va_mtime.tv_sec;
+		}
+	}
+	smb_makescred(&scred, p, cred);
+	return smb_read(smp->sm_share, np->n_fid, uiop, &scred);
+}
+
+int
+smbfs_writevnode(struct vnode *vp, struct uio *uiop,
+	struct ucred *cred, int ioflag)
+{
+	struct smbmount *smp = VTOSMBFS(vp);
+	struct smbnode *np = VTOSMB(vp);
+	struct smb_cred scred;
+	struct proc *p;
+	int error = 0;
+
+	if (vp->v_type != VREG) {
+		SMBERROR("vn types other than VREG unsupported !\n");
+		return EIO;
+	}
+	SMBVDEBUG("ofs=%d,resid=%d\n",(int)uiop->uio_offset, uiop->uio_resid);
+	if (uiop->uio_offset < 0)
+		return EINVAL;
+/*	if (uiop->uio_offset + uiop->uio_resid > smp->nm_maxfilesize)
+		return (EFBIG);*/
+	p = uiop->uio_procp;
+	if (ioflag & (IO_APPEND | IO_SYNC)) {
+		if (np->n_flag & NMODIFIED) {
+			smbfs_attr_cacheremove(vp);
+			error = smbfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+			if (error)
+				return error;
+		}
+		if (ioflag & IO_APPEND) {
+#if notyet
+			/*
+			 * File size can be changed by another client
+			 */
+			smbfs_attr_cacheremove(vp);
+			error = VOP_GETATTR(vp, &vattr, cred, p);
+			if (error) return (error);
+#endif
+			uiop->uio_offset = np->n_size;
+		}
+	}
+	if (uiop->uio_resid == 0)
+		return 0;
+	if (p && uiop->uio_offset + uiop->uio_resid > p->p_rlimit[RLIMIT_FSIZE].rlim_cur) {
+		psignal(p, SIGXFSZ);
+		return EFBIG;
+	}
+	smb_makescred(&scred, p, cred);
+	error = smb_write(smp->sm_share, np->n_fid, uiop, &scred);
+	SMBVDEBUG("after: ofs=%d,resid=%d\n",(int)uiop->uio_offset, uiop->uio_resid);
+	if (!error) {
+		if (uiop->uio_offset > np->n_size) {
+			np->n_size = uiop->uio_offset;
+			vnode_pager_setsize(vp, np->n_size);
+		}
+	}
+	return error;
+}
+
+/*
+ * Do an I/O operation to/from a cache block.
+ */
+int
+smbfs_doio(struct buf *bp, struct ucred *cr, struct proc *p)
+{
+	struct vnode *vp = bp->b_vp;
+	struct smbmount *smp = VFSTOSMBFS(vp->v_mount);
+	struct smbnode *np = VTOSMB(vp);
+	struct uio uio, *uiop = &uio;
+	struct iovec io;
+	struct smb_cred scred;
+	int error = 0;
+
+	uiop->uio_iov = &io;
+	uiop->uio_iovcnt = 1;
+	uiop->uio_segflg = UIO_SYSSPACE;
+	uiop->uio_procp = p;
+
+	smb_makescred(&scred, p, cr);
+
+	if (bp->b_iocmd == BIO_READ) {
+	    io.iov_len = uiop->uio_resid = bp->b_bcount;
+	    io.iov_base = bp->b_data;
+	    uiop->uio_rw = UIO_READ;
+	    switch (vp->v_type) {
+	      case VREG:
+		uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE;
+		error = smb_read(smp->sm_share, np->n_fid, uiop, &scred);
+		if (error)
+			break;
+		if (uiop->uio_resid) {
+			int left = uiop->uio_resid;
+			int nread = bp->b_bcount - left;
+			if (left > 0)
+			    bzero((char *)bp->b_data + nread, left);
+		}
+		break;
+	    default:
+		printf("smbfs_doio:  type %x unexpected\n",vp->v_type);
+		break;
+	    };
+	    if (error) {
+		bp->b_error = error;
+		bp->b_ioflags |= BIO_ERROR;
+	    }
+	} else { /* write */
+	    if (((bp->b_blkno * DEV_BSIZE) + bp->b_dirtyend) > np->n_size)
+		bp->b_dirtyend = np->n_size - (bp->b_blkno * DEV_BSIZE);
+
+	    if (bp->b_dirtyend > bp->b_dirtyoff) {
+		io.iov_len = uiop->uio_resid = bp->b_dirtyend - bp->b_dirtyoff;
+		uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff;
+		io.iov_base = (char *)bp->b_data + bp->b_dirtyoff;
+		uiop->uio_rw = UIO_WRITE;
+		bp->b_flags |= B_WRITEINPROG;
+		error = smb_write(smp->sm_share, np->n_fid, uiop, &scred);
+		bp->b_flags &= ~B_WRITEINPROG;
+
+		/*
+		 * For an interrupted write, the buffer is still valid
+		 * and the write hasn't been pushed to the server yet,
+		 * so we can't set BIO_ERROR and report the interruption
+		 * by setting B_EINTR. For the B_ASYNC case, B_EINTR
+		 * is not relevant, so the rpc attempt is essentially
+		 * a noop.  For the case of a V3 write rpc not being
+		 * committed to stable storage, the block is still
+		 * dirty and requires either a commit rpc or another
+		 * write rpc with iomode == NFSV3WRITE_FILESYNC before
+		 * the block is reused. This is indicated by setting
+		 * the B_DELWRI and B_NEEDCOMMIT flags.
+		 */
+    		if (error == EINTR
+		    || (!error && (bp->b_flags & B_NEEDCOMMIT))) {
+			int s;
+
+			s = splbio();
+			bp->b_flags &= ~(B_INVAL|B_NOCACHE);
+			if ((bp->b_flags & B_ASYNC) == 0)
+			    bp->b_flags |= B_EINTR;
+			if ((bp->b_flags & B_PAGING) == 0) {
+			    bdirty(bp);
+			    bp->b_flags &= ~B_DONE;
+			}
+			if ((bp->b_flags & B_ASYNC) == 0)
+			    bp->b_flags |= B_EINTR;
+			splx(s);
+	    	} else {
+			if (error) {
+				bp->b_ioflags |= BIO_ERROR;
+				bp->b_error = error;
+			}
+			bp->b_dirtyoff = bp->b_dirtyend = 0;
+		}
+	    } else {
+		bp->b_resid = 0;
+		bufdone(bp);
+		return 0;
+	    }
+	}
+	bp->b_resid = uiop->uio_resid;
+	bufdone(bp);
+	return error;
+}
+
+/*
+ * Vnode op for VM getpages.
+ * Wish wish .... get rid from multiple IO routines
+ */
+int
+smbfs_getpages(ap)
+	struct vop_getpages_args /* {
+		struct vnode *a_vp;
+		vm_page_t *a_m;
+		int a_count;
+		int a_reqpage;
+		vm_ooffset_t a_offset;
+	} */ *ap;
+{
+#ifdef SMBFS_RWGENERIC
+	return vnode_pager_generic_getpages(ap->a_vp, ap->a_m, ap->a_count,
+		ap->a_reqpage);
+#else
+	int i, error, nextoff, size, toff, npages, count;
+	struct uio uio;
+	struct iovec iov;
+	vm_offset_t kva;
+	struct buf *bp;
+	struct vnode *vp;
+	struct proc *p;
+	struct ucred *cred;
+	struct smbmount *smp;
+	struct smbnode *np;
+	struct smb_cred scred;
+	vm_page_t *pages;
+
+	vp = ap->a_vp;
+	p = curproc;				/* XXX */
+	cred = curproc->p_ucred;		/* XXX */
+	np = VTOSMB(vp);
+	smp = VFSTOSMBFS(vp->v_mount);
+	pages = ap->a_m;
+	count = ap->a_count;
+
+	if (vp->v_object == NULL) {
+		printf("smbfs_getpages: called with non-merged cache vnode??\n");
+		return VM_PAGER_ERROR;
+	}
+	smb_makescred(&scred, p, cred);
+
+#if __FreeBSD_version >= 400000
+	bp = getpbuf(&smbfs_pbuf_freecnt);
+#else
+	bp = getpbuf();
+#endif
+	npages = btoc(count);
+	kva = (vm_offset_t) bp->b_data;
+	pmap_qenter(kva, pages, npages);
+
+	iov.iov_base = (caddr_t) kva;
+	iov.iov_len = count;
+	uio.uio_iov = &iov;
+	uio.uio_iovcnt = 1;
+	uio.uio_offset = IDX_TO_OFF(pages[0]->pindex);
+	uio.uio_resid = count;
+	uio.uio_segflg = UIO_SYSSPACE;
+	uio.uio_rw = UIO_READ;
+	uio.uio_procp = p;
+
+	error = smb_read(smp->sm_share, np->n_fid, &uio, &scred);
+	pmap_qremove(kva, npages);
+
+#if __FreeBSD_version >= 400000
+	relpbuf(bp, &smbfs_pbuf_freecnt);
+#else
+	relpbuf(bp);
+#endif
+
+	if (error && (uio.uio_resid == count)) {
+		printf("smbfs_getpages: error %d\n",error);
+		for (i = 0; i < npages; i++) {
+			if (ap->a_reqpage != i)
+				vnode_pager_freepage(pages[i]);
+		}
+		return VM_PAGER_ERROR;
+	}
+
+	size = count - uio.uio_resid;
+
+	for (i = 0, toff = 0; i < npages; i++, toff = nextoff) {
+		vm_page_t m;
+		nextoff = toff + PAGE_SIZE;
+		m = pages[i];
+
+		m->flags &= ~PG_ZERO;
+
+		if (nextoff <= size) {
+			m->valid = VM_PAGE_BITS_ALL;
+			m->dirty = 0;
+		} else {
+			int nvalid = ((size + DEV_BSIZE - 1) - toff) & ~(DEV_BSIZE - 1);
+			vm_page_set_validclean(m, 0, nvalid);
+		}
+		
+		if (i != ap->a_reqpage) {
+			/*
+			 * Whether or not to leave the page activated is up in
+			 * the air, but we should put the page on a page queue
+			 * somewhere (it already is in the object).  Result:
+			 * It appears that emperical results show that
+			 * deactivating pages is best.
+			 */
+
+			/*
+			 * Just in case someone was asking for this page we
+			 * now tell them that it is ok to use.
+			 */
+			if (!error) {
+				if (m->flags & PG_WANTED)
+					vm_page_activate(m);
+				else
+					vm_page_deactivate(m);
+				vm_page_wakeup(m);
+			} else {
+				vnode_pager_freepage(m);
+			}
+		}
+	}
+	return 0;
+#endif /* SMBFS_RWGENERIC */
+}
+
+/*
+ * Vnode op for VM putpages.
+ * possible bug: all IO done in sync mode
+ * Note that vop_close always invalidate pages before close, so it's
+ * not necessary to open vnode.
+ */
+int
+smbfs_putpages(ap)
+	struct vop_putpages_args /* {
+		struct vnode *a_vp;
+		vm_page_t *a_m;
+		int a_count;
+		int a_sync;
+		int *a_rtvals;
+		vm_ooffset_t a_offset;
+	} */ *ap;
+{
+	int error;
+	struct vnode *vp = ap->a_vp;
+	struct proc *p;
+	struct ucred *cred;
+
+#ifdef SMBFS_RWGENERIC
+	p = curproc;			/* XXX */
+	cred = p->p_ucred;		/* XXX */
+	VOP_OPEN(vp, FWRITE, cred, p);
+	error = vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count,
+		ap->a_sync, ap->a_rtvals);
+	VOP_CLOSE(vp, FWRITE, cred, p);
+	return error;
+#else
+	struct uio uio;
+	struct iovec iov;
+	vm_offset_t kva;
+	struct buf *bp;
+	int i, npages, count;
+	int *rtvals;
+	struct smbmount *smp;
+	struct smbnode *np;
+	struct smb_cred scred;
+	vm_page_t *pages;
+
+	p = curproc;			/* XXX */
+	cred = p->p_ucred;		/* XXX */
+/*	VOP_OPEN(vp, FWRITE, cred, p);*/
+	np = VTOSMB(vp);
+	smp = VFSTOSMBFS(vp->v_mount);
+	pages = ap->a_m;
+	count = ap->a_count;
+	rtvals = ap->a_rtvals;
+	npages = btoc(count);
+
+	for (i = 0; i < npages; i++) {
+		rtvals[i] = VM_PAGER_AGAIN;
+	}
+
+#if __FreeBSD_version >= 400000
+	bp = getpbuf(&smbfs_pbuf_freecnt);
+#else
+	bp = getpbuf();
+#endif
+	kva = (vm_offset_t) bp->b_data;
+	pmap_qenter(kva, pages, npages);
+
+	iov.iov_base = (caddr_t) kva;
+	iov.iov_len = count;
+	uio.uio_iov = &iov;
+	uio.uio_iovcnt = 1;
+	uio.uio_offset = IDX_TO_OFF(pages[0]->pindex);
+	uio.uio_resid = count;
+	uio.uio_segflg = UIO_SYSSPACE;
+	uio.uio_rw = UIO_WRITE;
+	uio.uio_procp = p;
+	SMBVDEBUG("ofs=%d,resid=%d\n",(int)uio.uio_offset, uio.uio_resid);
+
+	smb_makescred(&scred, p, cred);
+	error = smb_write(smp->sm_share, np->n_fid, &uio, &scred);
+/*	VOP_CLOSE(vp, FWRITE, cred, p);*/
+	SMBVDEBUG("paged write done: %d\n", error);
+
+	pmap_qremove(kva, npages);
+#if __FreeBSD_version >= 400000
+	relpbuf(bp, &smbfs_pbuf_freecnt);
+#else
+	relpbuf(bp);
+#endif
+
+	if (!error) {
+		int nwritten = round_page(count - uio.uio_resid) / PAGE_SIZE;
+		for (i = 0; i < nwritten; i++) {
+			rtvals[i] = VM_PAGER_OK;
+			pages[i]->dirty = 0;
+		}
+	}
+	return rtvals[0];
+#endif /* SMBFS_RWGENERIC */
+}
+
+/*
+ * Flush and invalidate all dirty buffers. If another process is already
+ * doing the flush, just wait for completion.
+ */
+int
+smbfs_vinvalbuf(vp, flags, cred, p, intrflg)
+	struct vnode *vp;
+	int flags;
+	struct ucred *cred;
+	struct proc *p;
+	int intrflg;
+{
+	struct smbnode *np = VTOSMB(vp);
+	int error = 0, slpflag, slptimeo;
+
+	if (vp->v_flag & VXLOCK)
+		return 0;
+	if (intrflg) {
+		slpflag = PCATCH;
+		slptimeo = 2 * hz;
+	} else {
+		slpflag = 0;
+		slptimeo = 0;
+	}
+	while (np->n_flag & NFLUSHINPROG) {
+		np->n_flag |= NFLUSHWANT;
+		error = tsleep((caddr_t)&np->n_flag, PRIBIO + 2, "smfsvinv", slptimeo);
+		error = smb_proc_intr(p);
+		if (error == EINTR && intrflg)
+			return EINTR;
+	}
+	np->n_flag |= NFLUSHINPROG;
+	error = vinvalbuf(vp, flags, cred, p, slpflag, 0);
+	while (error) {
+		if (intrflg && (error == ERESTART || error == EINTR)) {
+			np->n_flag &= ~NFLUSHINPROG;
+			if (np->n_flag & NFLUSHWANT) {
+				np->n_flag &= ~NFLUSHWANT;
+				wakeup((caddr_t)&np->n_flag);
+			}
+			return EINTR;
+		}
+		error = vinvalbuf(vp, flags, cred, p, slpflag, 0);
+	}
+	np->n_flag &= ~(NMODIFIED | NFLUSHINPROG);
+	if (np->n_flag & NFLUSHWANT) {
+		np->n_flag &= ~NFLUSHWANT;
+		wakeup((caddr_t)&np->n_flag);
+	}
+	return (error);
+}