Understanding the rationale behind dropping of "block devices"

[Poul-Henning Kamp]

--------
In message <20170121235131.GF1768 at funkthat.com>, John-Mark Gurney writes:
>Aijaz Baig wrote this message on Mon, Jan 16, 2017 at 14:19 +0530:
>> Nevertheless my question still holds. What does 'removing support for block
>> device' mean in this context? Was what I mentioned earlier with regards to
>> my understanding correct? Viz. all disk devices now have a character (or
>> raw) interface and are no longer served via the "page cache" but rather the
>> "buffer cache". Does that mean all disk accesses are now direct by passing
>> the file system??
>
>One of the other reasons block devices were removed was that if there
>was a write error on the underlying device, there was no way for the
>writer to know that the write failed.  This could/would lead to corrupted
>data which is bad.

This paper hopefully answers a lot of the questions:

    https://www.usenix.org/conference/bsdcon02/rethinking-dev-and-devices-unix-kernel


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