afs: Set error flag rather than return error from file status decode

Set a flag in the call struct to indicate an unmarshalling error rather
than return and handle an error from the decoding of file statuses.  This
flag is checked on a successful return from the delivery function.

Signed-off-by: David Howells <dhowells@redhat.com>

fs/afs/fsclient.c

@@ -56,16 +56,15 @@ static void xdr_dump_bad(const __be32 *bp)
 /*
  * decode an AFSFetchStatus block
  */
-static int xdr_decode_AFSFetchStatus(const __be32 **_bp,
+static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
-				     struct afs_call *call,
+				      struct afs_call *call,
-				     struct afs_status_cb *scb)
+				      struct afs_status_cb *scb)
 {
 	const struct afs_xdr_AFSFetchStatus *xdr = (const void *)*_bp;
 	struct afs_file_status *status = &scb->status;
 	bool inline_error = (call->operation_ID == afs_FS_InlineBulkStatus);
 	u64 data_version, size;
 	u32 type, abort_code;
-	int ret;
 
 	abort_code = ntohl(xdr->abort_code);
 
@@ -79,7 +78,7 @@ static int xdr_decode_AFSFetchStatus(const __be32 **_bp,
 			 */
 			status->abort_code = abort_code;
 			scb->have_error = true;
-			goto good;
+			goto advance;
 		}
 
 		pr_warn("Unknown AFSFetchStatus version %u\n", ntohl(xdr->if_version));
@@ -89,7 +88,7 @@ static int xdr_decode_AFSFetchStatus(const __be32 **_bp,
 	if (abort_code != 0 && inline_error) {
 		status->abort_code = abort_code;
 		scb->have_error = true;
-		goto good;
+		goto advance;
 	}
 
 	type = ntohl(xdr->type);
@@ -125,15 +124,13 @@ static int xdr_decode_AFSFetchStatus(const __be32 **_bp,
 	data_version |= (u64)ntohl(xdr->data_version_hi) << 32;
 	status->data_version = data_version;
 	scb->have_status = true;
-good:
-	ret = 0;
 advance:
 	*_bp = (const void *)*_bp + sizeof(*xdr);
-	return ret;
+	return;
 
 bad:
 	xdr_dump_bad(*_bp);
-	ret = afs_protocol_error(call, -EBADMSG, afs_eproto_bad_status);
+	afs_protocol_error(call, -EBADMSG, afs_eproto_bad_status);
 	goto advance;
 }
 
@@ -254,9 +251,7 @@ static int afs_deliver_fs_fetch_status_vnode(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSCallBack(&bp, call, call->out_scb);
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
@@ -419,9 +414,7 @@ static int afs_deliver_fs_fetch_data(struct afs_call *call)
 			return ret;
 
 		bp = call->buffer;
-		ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+		xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-		if (ret < 0)
-			return ret;
 		xdr_decode_AFSCallBack(&bp, call, call->out_scb);
 		xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
@@ -577,12 +570,8 @@ static int afs_deliver_fs_create_vnode(struct afs_call *call)
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
 	xdr_decode_AFSFid(&bp, call->out_fid);
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-		return ret;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSCallBack(&bp, call, call->out_scb);
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
@@ -691,9 +680,7 @@ static int afs_deliver_fs_dir_status_and_vol(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -784,12 +771,8 @@ static int afs_deliver_fs_link(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-		return ret;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -878,12 +861,8 @@ static int afs_deliver_fs_symlink(struct afs_call *call)
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
 	xdr_decode_AFSFid(&bp, call->out_fid);
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-		return ret;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -986,16 +965,12 @@ static int afs_deliver_fs_rename(struct afs_call *call)
 	if (ret < 0)
 		return ret;
 
+	bp = call->buffer;
 	/* If the two dirs are the same, we have two copies of the same status
 	 * report, so we just decode it twice.
 	 */
-	bp = call->buffer;
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_dir_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -1103,9 +1078,7 @@ static int afs_deliver_fs_store_data(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -1283,9 +1256,7 @@ static int afs_deliver_fs_store_status(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -1952,9 +1923,7 @@ static int afs_deliver_fs_fetch_status(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSCallBack(&bp, call, call->out_scb);
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
@@ -2060,10 +2029,7 @@ static int afs_deliver_fs_inline_bulk_status(struct afs_call *call)
 
 		bp = call->buffer;
 		scb = &call->out_scb[call->count];
-		ret = xdr_decode_AFSFetchStatus(&bp, call, scb);
+		xdr_decode_AFSFetchStatus(&bp, call, scb);
-		if (ret < 0)
-			return ret;
-
 		call->count++;
 		if (call->count < call->count2)
 			goto more_counts;
@@ -2241,9 +2207,7 @@ static int afs_deliver_fs_fetch_acl(struct afs_call *call)
 			return ret;
 
 		bp = call->buffer;
-		ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+		xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-		if (ret < 0)
-			return ret;
 		xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 		call->unmarshall++;
@@ -2324,9 +2288,7 @@ static int afs_deliver_fs_file_status_and_vol(struct afs_call *call)
 		return ret;
 
 	bp = call->buffer;
-	ret = xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_AFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_AFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");

fs/afs/internal.h

@@ -160,6 +160,7 @@ struct afs_call {
 	bool			upgrade;	/* T to request service upgrade */
 	bool			have_reply_time; /* T if have got reply_time */
 	bool			intr;		/* T if interruptible */
+	bool			unmarshalling_error; /* T if an unmarshalling error occurred */
 	u16			service_id;	/* Actual service ID (after upgrade) */
 	unsigned int		debug_id;	/* Trace ID */
 	u32			operation_ID;	/* operation ID for an incoming call */

fs/afs/rxrpc.c

@@ -540,6 +540,8 @@ static void afs_deliver_to_call(struct afs_call *call)
 
 		ret = call->type->deliver(call);
 		state = READ_ONCE(call->state);
+		if (ret == 0 && call->unmarshalling_error)
+			ret = -EBADMSG;
 		switch (ret) {
 		case 0:
 			afs_queue_call_work(call);
@@ -963,5 +965,7 @@ noinline int afs_protocol_error(struct afs_call *call, int error,
 				enum afs_eproto_cause cause)
 {
 	trace_afs_protocol_error(call, error, cause);
+	if (call)
+		call->unmarshalling_error = true;
 	return error;
 }

fs/afs/yfsclient.c

@@ -179,21 +179,20 @@ static void xdr_dump_bad(const __be32 *bp)
 /*
  * Decode a YFSFetchStatus block
  */
-static int xdr_decode_YFSFetchStatus(const __be32 **_bp,
+static void xdr_decode_YFSFetchStatus(const __be32 **_bp,
-				     struct afs_call *call,
+				      struct afs_call *call,
-				     struct afs_status_cb *scb)
+				      struct afs_status_cb *scb)
 {
 	const struct yfs_xdr_YFSFetchStatus *xdr = (const void *)*_bp;
 	struct afs_file_status *status = &scb->status;
 	u32 type;
-	int ret;
 
 	status->abort_code = ntohl(xdr->abort_code);
 	if (status->abort_code != 0) {
 		if (status->abort_code == VNOVNODE)
 			status->nlink = 0;
 		scb->have_error = true;
-		goto good;
+		goto advance;
 	}
 
 	type = ntohl(xdr->type);
@@ -221,15 +220,13 @@ static int xdr_decode_YFSFetchStatus(const __be32 **_bp,
 	status->size		= xdr_to_u64(xdr->size);
 	status->data_version	= xdr_to_u64(xdr->data_version);
 	scb->have_status	= true;
-good:
-	ret = 0;
 advance:
 	*_bp += xdr_size(xdr);
-	return ret;
+	return;
 
 bad:
 	xdr_dump_bad(*_bp);
-	ret = afs_protocol_error(call, -EBADMSG, afs_eproto_bad_status);
+	afs_protocol_error(call, -EBADMSG, afs_eproto_bad_status);
 	goto advance;
 }
 
@@ -348,9 +345,7 @@ static int yfs_deliver_fs_status_cb_and_volsync(struct afs_call *call)
 
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_YFSCallBack(&bp, call, call->out_scb);
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
 
@@ -372,9 +367,7 @@ static int yfs_deliver_status_and_volsync(struct afs_call *call)
 		return ret;
 
 	bp = call->buffer;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -534,9 +527,7 @@ static int yfs_deliver_fs_fetch_data64(struct afs_call *call)
 			return ret;
 
 		bp = call->buffer;
-		ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+		xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-		if (ret < 0)
-			return ret;
 		xdr_decode_YFSCallBack(&bp, call, call->out_scb);
 		xdr_decode_YFSVolSync(&bp, call->out_volsync);
 
@@ -644,12 +635,8 @@ static int yfs_deliver_fs_create_vnode(struct afs_call *call)
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
 	xdr_decode_YFSFid(&bp, call->out_fid);
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-		return ret;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_YFSCallBack(&bp, call, call->out_scb);
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
 
@@ -802,14 +789,9 @@ static int yfs_deliver_fs_remove_file2(struct afs_call *call)
 		return ret;
 
 	bp = call->buffer;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
-
 	xdr_decode_YFSFid(&bp, &fid);
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
-		return ret;
 	/* Was deleted if vnode->status.abort_code == VNOVNODE. */
 
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
@@ -889,10 +871,7 @@ static int yfs_deliver_fs_remove(struct afs_call *call)
 		return ret;
 
 	bp = call->buffer;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
-
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
 	return 0;
 }
@@ -974,12 +953,8 @@ static int yfs_deliver_fs_link(struct afs_call *call)
 		return ret;
 
 	bp = call->buffer;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-		return ret;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
 	_leave(" = 0 [done]");
 	return 0;
@@ -1061,12 +1036,8 @@ static int yfs_deliver_fs_symlink(struct afs_call *call)
 	/* unmarshall the reply once we've received all of it */
 	bp = call->buffer;
 	xdr_decode_YFSFid(&bp, call->out_fid);
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-	if (ret < 0)
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-		return ret;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
-		return ret;
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
 
 	_leave(" = 0 [done]");
@@ -1154,13 +1125,11 @@ static int yfs_deliver_fs_rename(struct afs_call *call)
 		return ret;
 
 	bp = call->buffer;
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
+	/* If the two dirs are the same, we have two copies of the same status
-	if (ret < 0)
+	 * report, so we just decode it twice.
-		return ret;
+	 */
-	ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_dir_scb);
-	if (ret < 0)
+	xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-		return ret;
-
 	xdr_decode_YFSVolSync(&bp, call->out_volsync);
 	_leave(" = 0 [done]");
 	return 0;
@@ -1845,9 +1814,7 @@ static int yfs_deliver_fs_inline_bulk_status(struct afs_call *call)
 
 		bp = call->buffer;
 		scb = &call->out_scb[call->count];
-		ret = xdr_decode_YFSFetchStatus(&bp, call, scb);
+		xdr_decode_YFSFetchStatus(&bp, call, scb);
-		if (ret < 0)
-			return ret;
 
 		call->count++;
 		if (call->count < call->count2)
@@ -2067,9 +2034,7 @@ static int yfs_deliver_fs_fetch_opaque_acl(struct afs_call *call)
 		bp = call->buffer;
 		yacl->inherit_flag = ntohl(*bp++);
 		yacl->num_cleaned = ntohl(*bp++);
-		ret = xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
+		xdr_decode_YFSFetchStatus(&bp, call, call->out_scb);
-		if (ret < 0)
-			return ret;
 		xdr_decode_YFSVolSync(&bp, call->out_volsync);
 
 		call->unmarshall++;