devlink: Allow large formatted message of binary output

Devlink supports pair output of name and value. When the value is
binary, it must be presented in an array. If the length of the binary
value exceeds fmsg limitation, break the value into chunks internally.
Signed-off-by: NAya Levin <ayal@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/devlink.h

@@ -967,8 +967,6 @@ int devlink_fmsg_u8_put(struct devlink_fmsg *fmsg, u8 value);
 int devlink_fmsg_u32_put(struct devlink_fmsg *fmsg, u32 value);
 int devlink_fmsg_u64_put(struct devlink_fmsg *fmsg, u64 value);
 int devlink_fmsg_string_put(struct devlink_fmsg *fmsg, const char *value);
-int devlink_fmsg_binary_put(struct devlink_fmsg *fmsg, const void *value,
-			    u16 value_len);
 
 int devlink_fmsg_bool_pair_put(struct devlink_fmsg *fmsg, const char *name,
 			       bool value);
@@ -981,7 +979,7 @@ int devlink_fmsg_u64_pair_put(struct devlink_fmsg *fmsg, const char *name,
 int devlink_fmsg_string_pair_put(struct devlink_fmsg *fmsg, const char *name,
 				 const char *value);
 int devlink_fmsg_binary_pair_put(struct devlink_fmsg *fmsg, const char *name,
-				 const void *value, u16 value_len);
+				 const void *value, u32 value_len);
 
 struct devlink_health_reporter *
 devlink_health_reporter_create(struct devlink *devlink,

net/core/devlink.c

@@ -4414,12 +4414,11 @@ int devlink_fmsg_string_put(struct devlink_fmsg *fmsg, const char *value)
 }
 EXPORT_SYMBOL_GPL(devlink_fmsg_string_put);
 
-int devlink_fmsg_binary_put(struct devlink_fmsg *fmsg, const void *value,
-			    u16 value_len)
+static int devlink_fmsg_binary_put(struct devlink_fmsg *fmsg, const void *value,
+				   u16 value_len)
 {
 	return devlink_fmsg_put_value(fmsg, value, value_len, NLA_BINARY);
 }
-EXPORT_SYMBOL_GPL(devlink_fmsg_binary_put);
 
 int devlink_fmsg_bool_pair_put(struct devlink_fmsg *fmsg, const char *name,
 			       bool value)
@@ -4527,19 +4526,26 @@ int devlink_fmsg_string_pair_put(struct devlink_fmsg *fmsg, const char *name,
 EXPORT_SYMBOL_GPL(devlink_fmsg_string_pair_put);
 
 int devlink_fmsg_binary_pair_put(struct devlink_fmsg *fmsg, const char *name,
-				 const void *value, u16 value_len)
+				 const void *value, u32 value_len)
 {
+	u32 data_size;
+	u32 offset;
 	int err;
 
-	err = devlink_fmsg_pair_nest_start(fmsg, name);
+	err = devlink_fmsg_arr_pair_nest_start(fmsg, name);
 	if (err)
 		return err;
 
-	err = devlink_fmsg_binary_put(fmsg, value, value_len);
-	if (err)
-		return err;
+	for (offset = 0; offset < value_len; offset += data_size) {
+		data_size = value_len - offset;
+		if (data_size > DEVLINK_FMSG_MAX_SIZE)
+			data_size = DEVLINK_FMSG_MAX_SIZE;
+		err = devlink_fmsg_binary_put(fmsg, value + offset, data_size);
+		if (err)
+			return err;
+	}
 
-	err = devlink_fmsg_pair_nest_end(fmsg);
+	err = devlink_fmsg_arr_pair_nest_end(fmsg);
 	if (err)
 		return err;