lotus-miner: add more help text to storage / attach

cmd/lotus-storage-miner/storage.go

@@ -31,6 +31,10 @@ const metaFile = "sectorstore.json"
 var storageCmd = &cli.Command{
 	Name:  "storage",
 	Usage: "manage sector storage",
+	Description: `Sectors can be stored across many filesystem paths. These
+commands provide ways to manage the storage the miner will used to store sectors
+long term for proving (references as 'store') as well as how sectors will be
+stored while moving through the sealing pipeline (references as 'seal').`,
 	Subcommands: []*cli.Command{
 		storageAttachCmd,
 		storageListCmd,
@@ -41,6 +45,25 @@ var storageCmd = &cli.Command{
 var storageAttachCmd = &cli.Command{
 	Name:  "attach",
 	Usage: "attach local storage path",
+	Description: `Storage can be attached to the miner using this command. The storage volume
+list is stored local to the miner in $LOTUS_MINER_PATH/storage.json. We do not
+recommend manually modifying this value without further understanding of the
+storage system.
+
+Each storage volume contains a configuration file which describes the
+capabilities of the volume. When the '--init' flag is provided, this file will
+be created using the additional flags.
+
+Weight
+A high weight value means data will be more likely to be stored in this path
+
+Seal
+Data for the sealing process will be stored here
+
+Store
+Finalized sectors that will be moved here for long term storage and be proven
+over time
+   `,
 	Flags: []cli.Flag{
 		&cli.BoolFlag{
 			Name:  "init",

extern/sector-storage/stores/local.go

@@ -30,10 +30,15 @@ type StoragePath struct {
 
 // LocalStorageMeta [path]/sectorstore.json
 type LocalStorageMeta struct {
-	ID     ID
+	ID ID
+
+	// A high weight means data is more likely to be stored in this path
 	Weight uint64 // 0 = readonly
 
-	CanSeal  bool
+	// Intermediate data for the sealing process will be stored here
+	CanSeal bool
+
+	// Finalized sectors that will be proved over time will be stored here
 	CanStore bool
 }