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Date: Sat, 22 Dec 2012 11:37:02 +0800
Subject: The relationship between flag: BH_Uptodate & BH_Dirty in 
 buffer_head
From: cyhung.cs00g@nctu.edu.tw
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Hi, all

I want ask a question.

As we know, structure buffer_head has a member called b_state.
And this state could be defined by many flags.

The question is that, I want to know the relationship between BH_Uptodate
& BH_Dirty.

If a data is verified, the BH_Dirty will setup, and what about BH_Uptodate?

Under what circumstance the BH_Uptodate would be set up?


Thanks. :)