Re: [PATCH 3/5] pagemap: Make pagemap_read enforce reading in multiples of 8

From: Thomas Tuttle
Date: Thu Jun 05 2008 - 12:15:33 EST


On Thu, Jun 5, 2008 at 12:09 PM, Matt Mackall <mpm@xxxxxxxxxxx> wrote:
> Yes, I got that, I'm just mathematically impaired this morning. Read
> that as "when someone tries to do a *20* byte read, do a 16-byte read.."
> In other words, round down to the nearest multiple of 8.

Oh. I would seriously question doing that, because it would allow
reads that are improperly split up to fail silently. What happens if
someone tries to read 40 bytes, and (for some reason) it gets split
into two 20-byte reads? Instead of "12345" they'll get "12.34."
(where . is 4 zero or garbage bytes). I'd rather they get an error.

--ttuttle
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