svn commit: r199460 - in user/kmacy/releng_8_fcs_buf/sys: cddl/contrib/opensolaris/uts/common/fs/zfs sys

[Kip Macy]

Author: kmacy
Date: Wed Nov 18 00:04:03 2009
New Revision: 199460
URL: http://svn.freebsd.org/changeset/base/199460

Log:
  don't rely on b_offset to be unmodified

Modified:
  user/kmacy/releng_8_fcs_buf/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
  user/kmacy/releng_8_fcs_buf/sys/sys/buf.h

Modified: user/kmacy/releng_8_fcs_buf/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c
==============================================================================
--- user/kmacy/releng_8_fcs_buf/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	Tue Nov 17 23:03:38 2009	(r199459)
+++ user/kmacy/releng_8_fcs_buf/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/arc.c	Wed Nov 18 00:04:03 2009	(r199460)
@@ -452,6 +452,7 @@ struct arc_write_callback {
 	arc_buf_t	*awcb_buf;
 };
 
+
 struct arc_buf_hdr {
 	/* protected by hash lock */
 	dva_t			b_dva;
@@ -1307,11 +1308,14 @@ arc_bgetvp(arc_buf_t *buf)
 	struct bufobj *bo = &vp->v_bufobj;
 	arc_buf_hdr_t *hdr = buf->b_hdr;
 
-	if (blkno == 0)
+	if (zfs_page_cache_disable)
+		return;
+
+	if (blkno == 0 || hdr->b_birth == 0)
 		return;
 
 	newbp = buf->b_bp;
-	newbp->b_offset = hdr->b_birth;
+	newbp->b_birth = hdr->b_birth;
 	newbp->b_blkno = newbp->b_lblkno = blkno;
 
 	BO_LOCK(bo);
@@ -1325,11 +1329,16 @@ arc_bgetvp(arc_buf_t *buf)
 		/*
 		 * buffer is usable for this mapping
 		 */
-		if (!(hdr->b_flags & ARC_IO_ERROR) &&
-		    (bp->b_offset <= hdr->b_birth) &&
-		    (bp->b_flags & (B_CACHE|B_INVAL)) == B_CACHE) { 
+		if (((bp->b_flags & (B_CACHE|B_INVAL)) == B_CACHE) &&
+		    (bp->b_birth > hdr->b_birth)) {
+			brelse(bp);
+		} else if (hdr->b_flags & ARC_IO_ERROR) {
 			bp->b_flags |= B_INVAL;
-			bp->b_flags &= ~B_CACHE;
+			bp->b_birth = 0;
+			brelse(bp);
+		} else {
+			bp->b_flags |= B_INVAL;
+			bp->b_birth = 0;
 			brelse(bp);
 			
 			newbp->b_flags |= B_CACHE;
@@ -1338,8 +1347,7 @@ arc_bgetvp(arc_buf_t *buf)
 			BO_LOCK(bo);
 			bgetvp(vp, newbp);
 			BO_UNLOCK(bo);
-		} else
-			brelse(bp);
+		}
 	} else {
 		newbp->b_flags |= B_CACHE;
 		newbp->b_flags &= ~B_INVAL;

Modified: user/kmacy/releng_8_fcs_buf/sys/sys/buf.h
==============================================================================
--- user/kmacy/releng_8_fcs_buf/sys/sys/buf.h	Tue Nov 17 23:03:38 2009	(r199459)
+++ user/kmacy/releng_8_fcs_buf/sys/sys/buf.h	Wed Nov 18 00:04:03 2009	(r199460)
@@ -104,7 +104,8 @@ struct buf {
 	long		b_resid;
 	void	(*b_iodone)(struct buf *);
 	daddr_t b_blkno;		/* Underlying physical block number. */
-	off_t	b_offset;		/* Offset into file. */
+	off_t		b_offset;	/* Offset into file. */
+	uint64_t	b_birth;	/* birth txg	    */	 
 	TAILQ_ENTRY(buf) b_bobufs;	/* (V) Buffer's associated vnode. */
 	struct buf	*b_left;	/* (V) splay tree link */
 	struct buf	*b_right;	/* (V) splay tree link */