Various of the ISP users have commented that the 1.41 version of the

nfs_bio.c code worked better than the 1.44.  This commit reverts
the important parts of 1.44 to 1.41, and we will fix it when we
can get a handle on the problem.

1 files changed, 19 insertions, 115 deletions

diff --git a/sys/nfsclient/nfs_bio.c b/sys/nfsclient/nfs_bio.c
index 2479c6ad..0356f42 100644
--- a/sys/nfsclient/nfs_bio.c
+++ b/sys/nfsclient/nfs_bio.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)nfs_bio.c	8.9 (Berkeley) 3/30/95
- * $Id: nfs_bio.c,v 1.43 1997/08/02 14:33:06 bde Exp $
+ * $Id: nfs_bio.c,v 1.44 1997/09/10 19:52:25 phk Exp $
  */
 
 
@@ -65,9 +65,6 @@
 
 static struct buf *nfs_getcacheblk __P((struct vnode *vp, daddr_t bn, int size,
 					struct proc *p));
-static struct buf *nfs_getwriteblk __P((struct vnode *vp, daddr_t bn,
-					int size, struct proc *p,
-					struct ucred *cred, int off, int len));
 
 extern int nfs_numasync;
 extern struct nfsstats nfsstats;
@@ -596,7 +593,7 @@ again:
 			bufsize = np->n_size - lbn * biosize;
 			bufsize = (bufsize + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1);
 		}
-		bp = nfs_getwriteblk(vp, lbn, bufsize, p, cred, on, n);
+		bp = nfs_getcacheblk(vp, lbn, bufsize, p);
 		if (!bp)
 			return (EINTR);
 		if (bp->b_wcred == NOCRED) {
@@ -605,6 +602,23 @@ again:
 		}
 		np->n_flag |= NMODIFIED;
 
+		if ((bp->b_blkno * DEV_BSIZE) + bp->b_dirtyend > np->n_size) {
+			bp->b_dirtyend = np->n_size - (bp->b_blkno * DEV_BSIZE);
+		}
+
+		/*
+		 * If the new write will leave a contiguous dirty
+		 * area, just update the b_dirtyoff and b_dirtyend,
+		 * otherwise force a write rpc of the old dirty area.
+		 */
+		if (bp->b_dirtyend > 0 &&
+		    (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) {
+			bp->b_proc = p;
+			if (VOP_BWRITE(bp) == EINTR)
+				return (EINTR);
+			goto again;
+		}
+
 		/*
 		 * Check for valid write lease and get one as required.
 		 * In case getblk() and/or bwrite() delayed us.
@@ -681,116 +695,6 @@ again:
 }
 
 /*
- * Get a cache block for writing.  The range to be written is
- * (off..off+len) within the block.  This routine ensures that the
- * block is either has no dirty region or that the given range is
- * contiguous with the existing dirty region.
- */
-static struct buf *
-nfs_getwriteblk(vp, bn, size, p, cred, off, len)
-	struct vnode *vp;
-	daddr_t bn;
-	int size;
-	struct proc *p;
-	struct ucred *cred;
-	int off, len;
-{
-	struct nfsnode *np = VTONFS(vp);
-	struct buf *bp;
-	int error;
-
- again:
-	bp = nfs_getcacheblk(vp, bn, size, p);
-	if (!bp)
-		return (NULL);
-	if (bp->b_wcred == NOCRED) {
-		crhold(cred);
-		bp->b_wcred = cred;
-	}
-
-	if ((bp->b_blkno * DEV_BSIZE) + bp->b_dirtyend > np->n_size) {
-		bp->b_dirtyend = np->n_size - (bp->b_blkno * DEV_BSIZE);
-	}
-
-	/*
-	 * If the new write will leave a contiguous dirty
-	 * area, just update the b_dirtyoff and b_dirtyend,
-	 * otherwise try to extend the dirty region.
-	 */
-	if (bp->b_dirtyend > 0 &&
-	    (off > bp->b_dirtyend || (off + len) < bp->b_dirtyoff)) {
-		struct iovec iov;
-		struct uio uio;
-		off_t boff, start, end;
-
-		boff = ((off_t)bp->b_blkno) * DEV_BSIZE;
-		if (off > bp->b_dirtyend) {
-			start = boff + bp->b_validend;
-			end = boff + off;
-		} else {
-			start = boff + off + len;
-			end = boff + bp->b_validoff;
-		}
-		
-		/*
-		 * It may be that the valid region in the buffer
-		 * covers the region we want, in which case just
-		 * extend the dirty region.  Otherwise we try to
-		 * extend the valid region.
-		 */
-		if (end > start) {
-			uio.uio_iov = &iov;
-			uio.uio_iovcnt = 1;
-			uio.uio_offset = start;
-			uio.uio_resid = end - start;
-			uio.uio_segflg = UIO_SYSSPACE;
-			uio.uio_rw = UIO_READ;
-			uio.uio_procp = p;
-			iov.iov_base = bp->b_data + (start - boff);
-			iov.iov_len = end - start;
-			error = nfs_readrpc(vp, &uio, cred);
-			if (error) {
-				/*
-				 * If we couldn't read, fall back to writing
-				 * out the old dirty region.
-				 */
-				bp->b_proc = p;
-				if (VOP_BWRITE(bp) == EINTR)
-					return (NULL);
-				goto again;
-			} else {
-				/*
-				 * The read worked.
-				 */
-				if (uio.uio_resid > 0) {
-					/*
-					 * If there was a short read,
-					 * just zero fill.
-					 */
-					bzero(iov.iov_base,
-					      uio.uio_resid);
-				}
-				if (off > bp->b_dirtyend)
-					bp->b_validend = off;
-				else
-					bp->b_validoff = off + len;
-			}
-		}
-
-		/*
-		 * We now have a valid region which extends up to the
-		 * dirty region which we want.
-		 */
-		if (off > bp->b_dirtyend)
-			bp->b_dirtyend = off;
-		else
-			bp->b_dirtyoff = off + len;
-	}
-
-	return bp;
-}
-
-/*
  * Get an nfs cache block.
  * Allocate a new one if the block isn't currently in the cache
  * and return the block marked busy. If the calling process is