Re: Kmalloc

Norm Dresner <ndrez@xxxxxxx> wrote:
> "Peter T. Breuer" <ptb@xxxxxxxxxxxxxxx> wrote in message
> news:0gru93-le4.ln1@xxxxxxxxxxxxxxxxxx
>> Anand <anand.vt@xxxxxxxxx> wrote:
>>> Can any one help in knowing whether Kmalloc will always allocate
>>> contiguous memory.
>>
>> Yep, never. And you don't know anyway, since the addresses you see are
>> remapped from the physical addresses. So - non-question.

> Umm ... if the buffer in question is being allocated for DMA purposes, it's
> vital to know if it's physically contiguous or not. It's not a
> "non-question".

Actuallywise, I should apologize, because I read that as "malloc", for
some reason, not "kmalloc", thus changing the sense of the question.

Kmalloc does deliver contiguous lumps of underlying physical memory even
taking remapping into account, I believe, even if a 4K boundary is
crossed (at least, using the buddy allocater). But caveat emptor - I'm
only really sure up to 4KB.

Peter
.

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