[XFS] Fix attr2 corruption with btree data extents

SGI-PV: 958747
SGI-Modid: xfs-linux-melb:xfs-kern:27792a
Signed-off-by: Barry Naujok <bnaujok@sgi.com>
Signed-off-by: Russell Cattelan <cattelan@thebarn.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>

fs/xfs/xfs_attr.c

@@ -198,19 +198,15 @@ xfs_attr_set_int(xfs_inode_t *dp, const char *name, int namelen,
 	if ((error = XFS_QM_DQATTACH(mp, dp, 0)))
 		return (error);
 
-	/*
-	 * Determine space new attribute will use, and if it would be
-	 * "local" or "remote" (note: local != inline).
-	 */
-	size = xfs_attr_leaf_newentsize(namelen, valuelen,
-					mp->m_sb.sb_blocksize, &local);
-
 	/*
 	 * If the inode doesn't have an attribute fork, add one.
 	 * (inode must not be locked when we call this routine)
 	 */
 	if (XFS_IFORK_Q(dp) == 0) {
-		if ((error = xfs_bmap_add_attrfork(dp, size, rsvd)))
+		int sf_size = sizeof(xfs_attr_sf_hdr_t) +
+			      XFS_ATTR_SF_ENTSIZE_BYNAME(namelen, valuelen);
+
+		if ((error = xfs_bmap_add_attrfork(dp, sf_size, rsvd)))
 			return(error);
 	}
 
@@ -231,6 +227,13 @@ xfs_attr_set_int(xfs_inode_t *dp, const char *name, int namelen,
 	args.addname = 1;
 	args.oknoent = 1;
 
+	/*
+	 * Determine space new attribute will use, and if it would be
+	 * "local" or "remote" (note: local != inline).
+	 */
+	size = xfs_attr_leaf_newentsize(namelen, valuelen,
+					mp->m_sb.sb_blocksize, &local);
+
 	nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
 	if (local) {
 		if (size > (mp->m_sb.sb_blocksize >> 1)) {

fs/xfs/xfs_attr_leaf.c

@@ -150,6 +150,7 @@ xfs_attr_shortform_bytesfit(xfs_inode_t *dp, int bytes)
 	int offset;
 	int minforkoff;	/* lower limit on valid forkoff locations */
 	int maxforkoff;	/* upper limit on valid forkoff locations */
+	int dsize;	
 	xfs_mount_t *mp = dp->i_mount;
 
 	offset = (XFS_LITINO(mp) - bytes) >> 3; /* rounded down */
@@ -169,8 +170,43 @@ xfs_attr_shortform_bytesfit(xfs_inode_t *dp, int bytes)
 		return 0;
 	}
 
-	/* data fork btree root can have at least this many key/ptr pairs */
-	minforkoff = MAX(dp->i_df.if_bytes, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
+	dsize = dp->i_df.if_bytes;
+	
+	switch (dp->i_d.di_format) {
+	case XFS_DINODE_FMT_EXTENTS:
+		/* 
+		 * If there is no attr fork and the data fork is extents, 
+		 * determine if creating the default attr fork will result 
+		 * in the extents form migrating to btree. If so, the 
+		 * minimum offset only needs to be the space required for 
+		 * the btree root.
+		 */ 
+		if (!dp->i_d.di_forkoff && dp->i_df.if_bytes > mp->m_attroffset)
+			dsize = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
+		break;
+		
+	case XFS_DINODE_FMT_BTREE:
+		/*
+		 * If have data btree then keep forkoff if we have one,
+		 * otherwise we are adding a new attr, so then we set 
+		 * minforkoff to where the btree root can finish so we have 
+		 * plenty of room for attrs
+		 */
+		if (dp->i_d.di_forkoff) {
+			if (offset < dp->i_d.di_forkoff) 
+				return 0;
+			else 
+				return dp->i_d.di_forkoff;
+		} else
+			dsize = XFS_BMAP_BROOT_SPACE(dp->i_df.if_broot);
+		break;
+	}
+	
+	/* 
+	 * A data fork btree root must have space for at least 
+	 * MINDBTPTRS key/ptr pairs if the data fork is small or empty.
+	 */
+	minforkoff = MAX(dsize, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
 	minforkoff = roundup(minforkoff, 8) >> 3;
 
 	/* attr fork btree root can have at least this many key/ptr pairs */
@@ -336,7 +372,8 @@ xfs_attr_shortform_remove(xfs_da_args_t *args)
 	 */
 	totsize -= size;
 	if (totsize == sizeof(xfs_attr_sf_hdr_t) && !args->addname &&
-	    (mp->m_flags & XFS_MOUNT_ATTR2)) {
+	    (mp->m_flags & XFS_MOUNT_ATTR2) && 
+	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE)) {
 		/*
 		 * Last attribute now removed, revert to original
 		 * inode format making all literal area available
@@ -748,6 +785,7 @@ xfs_attr_shortform_allfit(xfs_dabuf_t *bp, xfs_inode_t *dp)
 				+ be16_to_cpu(name_loc->valuelen);
 	}
 	if ((dp->i_mount->m_flags & XFS_MOUNT_ATTR2) &&
+	    (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
 	    (bytes == sizeof(struct xfs_attr_sf_hdr)))
 		return(-1);
 	return(xfs_attr_shortform_bytesfit(dp, bytes));
@@ -786,6 +824,7 @@ xfs_attr_leaf_to_shortform(xfs_dabuf_t *bp, xfs_da_args_t *args, int forkoff)
 
 	if (forkoff == -1) {
 		ASSERT(dp->i_mount->m_flags & XFS_MOUNT_ATTR2);
+		ASSERT(dp->i_d.di_format != XFS_DINODE_FMT_BTREE);
 
 		/*
 		 * Last attribute was removed, revert to original

fs/xfs/xfs_bmap.c

@@ -3543,6 +3543,7 @@ xfs_bmap_forkoff_reset(
 	if (whichfork == XFS_ATTR_FORK &&
 	    (ip->i_d.di_format != XFS_DINODE_FMT_DEV) &&
 	    (ip->i_d.di_format != XFS_DINODE_FMT_UUID) &&
+	    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
 	    ((mp->m_attroffset >> 3) > ip->i_d.di_forkoff)) {
 		ip->i_d.di_forkoff = mp->m_attroffset >> 3;
 		ip->i_df.if_ext_max = XFS_IFORK_DSIZE(ip) /