Coda File System

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4. Volumes

Volumes are recorded using an umbrella data structure called the volume database (VDB), defined in venusvol.h.

Contained in the volume database are above all entries for individual volumes: volents. Volents are stored in persistent storage. Volents are described in venusvol.h as well and contain the following important fields:

XXX What are observers? What are pre-allocated fids?

A volume carries a client modification log. The umbrella data structure is the ClientModifyLog, which contains entries of type cmlent. These are all persistent. A structure of type ClientModifyLog has an owner, who is responsible for writing all the entries of the log. XXX What is an mle versus a cmle

An entry in the CML is a higly technical structure reflecting the filesystem updates. It contains opcodes and a union (u) of data containing the fid and update details. All cmlents are held in RVM.

A very small structure holds the data associated to a cop2 event. This data is transient. cop2ent -- entry for pending COP2 events (transient)

Another small structure holds data associated with fids needing resolution.

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