cvs commit: src/sbin/atacontrol atacontrol.c

[Poul-Henning Kamp]

In message <4766951B.8090504 at incunabulum.net>, Bruce M Simpson writes:

>Ah, let me rephrase, I meant:
>
>* NAND Flash embedded ATA controllers should not erase sectors 
>containing data unless absolutely necessary, to implement wear levelling.

That's part of the job description, but it is more complex than that.

> * BIO_DELETE provides the necessary hint from the OS, by way of the ATA 
>CFA ERASE command, to tell the flash controller that the upper layer 
>consumer of the blocks has marked the data as being erased.

Yes.

> * The NAND flash ATA controller is *then* in a position to know how 
>best to implement that wear levelling as the OS has told it "I'm not 
>using these sectors any more".

Possibly.  For "best" substitute "better" and I might agree.

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