[PATCH v2 16/18] xfs: Roll delayed attr operations by returning EAGAIN

[Allison Collins <allison.henderson@oracle.com>]

Modify delayed operations to use the new xfs_attr_da*
routines

In this patch, xfs_trans_attr is modified to use the new
xfs_attr_da_* scheme, and pass the -EAGAIN back to the
calling function.  The leaf_bp is also factored up to
be released after the transactions are handled.

xfs_attri_recover will need to handle the -EAGAIN by
logging and committing the transaction before recalling
xfs_trans_attr.

xfs_attr_finish_item does not need to handle the -EAGAIN
since it is handled by its calling function.  But it
does need to plumb in xfs_da_args from the log item since
it cant keep args instantiated in its own function context.

Signed-off-by: Allison Collins <allison.henderson@oracle.com>
---
 fs/xfs/xfs_attr_item.c | 83 +++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 62 insertions(+), 21 deletions(-)

diff --git a/fs/xfs/xfs_attr_item.c b/fs/xfs/xfs_attr_item.c
index 88efaf9..6693880 100644
--- a/fs/xfs/xfs_attr_item.c
+++ b/fs/xfs/xfs_attr_item.c
@@ -65,6 +65,7 @@ int
 xfs_trans_attr(
 	struct xfs_da_args		*args,
 	struct xfs_attrd_log_item	*attrdp,
+	struct xfs_buf			**leaf_bp,
 	uint32_t			op_flags)
 {
 	int				error;
@@ -76,11 +77,11 @@ xfs_trans_attr(
 	switch (op_flags) {
 	case XFS_ATTR_OP_FLAGS_SET:
 		args->op_flags |= XFS_DA_OP_ADDNAME;
-		error = xfs_attr_set_args(args);
+		error = xfs_attr_da_set_args(args, leaf_bp);
 		break;
 	case XFS_ATTR_OP_FLAGS_REMOVE:
 		ASSERT(XFS_IFORK_Q((args->dp)));
-		error = xfs_attr_remove_args(args);
+		error = xfs_attr_da_remove_args(args);
 		break;
 	default:
 		error = -EFSCORRUPTED;
@@ -187,29 +188,40 @@ xfs_attr_finish_item(
 	char				*name_value;
 	int				error;
 	int				local;
-	struct xfs_da_args		args;
+	struct xfs_da_args		*args;
 	struct xfs_name			name;
 	struct xfs_attrd_log_item	*attrdp;
 	struct xfs_attri_log_item	*attrip;
 
 	attr = container_of(item, struct xfs_attr_item, xattri_list);
-	name_value = ((char *)attr) + sizeof(struct xfs_attr_item);
+	args = &attr->xattri_args;
 
+	name_value = ((char *)attr) + sizeof(struct xfs_attr_item);
 	name.name = name_value;
 	name.len = attr->xattri_name_len;
 	name.type = attr->xattri_flags;
-	error = xfs_attr_args_init(&args, attr->xattri_ip, &name);
-	if (error)
-		goto out;
 
-	args.hashval = xfs_da_hashname(args.name, args.namelen);
-	args.value = &name_value[attr->xattri_name_len];
-	args.valuelen = attr->xattri_value_len;
-	args.op_flags = XFS_DA_OP_OKNOENT;
-	args.total = xfs_attr_calc_size(&args, &local);
-	args.trans = tp;
+	if (!(args->dc.flags & XFS_DC_INIT)) {
+		/* Only need to initialize args context once */
+		error = xfs_attr_args_init(args, attr->xattri_ip, &name);
+		if (error)
+			goto out;
+
+		args->hashval = xfs_da_hashname(args->name, args->namelen);
+		args->value = &name_value[attr->xattri_name_len];
+		args->valuelen = attr->xattri_value_len;
+		args->op_flags = XFS_DA_OP_OKNOENT;
+		args->total = xfs_attr_calc_size(args, &local);
+		args->dc.flags |= XFS_DC_INIT;
+	}
+
+	/*
+	 * Always reset trans after EAGAIN cycle
+	 * since the transaction is new
+	 */
+	args->trans = tp;
 
-	error = xfs_trans_attr(&args, done_item,
+	error = xfs_trans_attr(args, done_item, &args->dc.leaf_bp,
 			attr->xattri_op_flags);
 out:
 	/*
@@ -223,7 +235,9 @@ xfs_attr_finish_item(
 	attrip->attri_name_len = 0;
 	attrip->attri_value_len = 0;
 
-	kmem_free(attr);
+	if (error != -EAGAIN)
+		kmem_free(attr);
+
 	return error;
 }
 
@@ -678,9 +692,10 @@ xfs_attri_recover(
 	struct xfs_attri_log_format	*attrp;
 	struct xfs_trans_res		tres;
 	int				local;
-	int				error = 0;
+	int				error, err2 = 0;
 	int				rsvd = 0;
 	struct xfs_name			name;
+	struct xfs_buf			*leaf_bp = NULL;
 
 	ASSERT(!test_bit(XFS_ATTRI_RECOVERED, &attrip->attri_flags));
 
@@ -737,14 +752,40 @@ xfs_attri_recover(
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
 
 	xfs_trans_ijoin(args.trans, ip, 0);
-	error = xfs_trans_attr(&args, attrdp, attrp->alfi_op_flags);
-	if (error)
-		goto abort_error;
 
+	do {
+		leaf_bp = NULL;
+
+		error = xfs_trans_attr(&args, attrdp, &leaf_bp,
+				       attrp->alfi_op_flags);
+		if (error && error != -EAGAIN)
+			goto abort_error;
+
+		xfs_trans_log_inode(args.trans, ip,
+				XFS_ILOG_CORE | XFS_ILOG_ADATA);
+
+		err2 = xfs_trans_commit(args.trans);
+		if (err2) {
+			error = err2;
+			goto abort_error;
+		}
+
+		if (error == -EAGAIN) {
+			err2 = xfs_trans_alloc(mp, &tres, args.total, 0,
+				XFS_TRANS_PERM_LOG_RES, &args.trans);
+			if (err2) {
+				error = err2;
+				goto abort_error;
+			}
+			xfs_trans_ijoin(args.trans, ip, 0);
+		}
+
+	} while (error == -EAGAIN);
+
+	if (leaf_bp)
+		xfs_trans_brelse(args.trans, leaf_bp);
 
 	set_bit(XFS_ATTRI_RECOVERED, &attrip->attri_flags);
-	xfs_trans_log_inode(args.trans, ip, XFS_ILOG_CORE | XFS_ILOG_ADATA);
-	error = xfs_trans_commit(args.trans);
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 	return error;
 
-- 
2.7.4