From: Matthew Wilcox <willy@infradead.org>
To: Christoph Hellwig <hch@infradead.org>
Cc: David Howells <dhowells@redhat.com>,
Jesper Dangaard Brouer <brouer@redhat.com>,
Christoph Lameter <cl@linux.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-mm <linux-mm@kvack.org>
Subject: Re: Bulk kmalloc
Date: Fri, 10 May 2019 10:35:29 -0700 [thread overview]
Message-ID: <20190510173529.GA24921@bombadil.infradead.org> (raw)
In-Reply-To: <20190510171110.GA3449@infradead.org>
On Fri, May 10, 2019 at 10:11:10AM -0700, Christoph Hellwig wrote:
> On Fri, May 10, 2019 at 09:50:01AM -0700, Matthew Wilcox wrote:
> > kvmalloc() is the normal solution here. Usual reasons for not being
> > able to do that would be that you do DMA to the memory or that you need
> > to be able to free each of these objects individually.
>
> Note that you absolutely can do DMA to vmalloced buffers. It just is
> very painful due to the manual coherency management..
... and we don't have proper APIs for it. The last time we discussed
it was January, I think.
https://lore.kernel.org/patchwork/patch/1033921/
I haven't made any effort to try to come up with decent APIs for this.
next prev parent reply other threads:[~2019-05-10 17:35 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <14647.1557415738@warthog.procyon.org.uk>
2019-05-10 11:50 ` Bulk kmalloc Jesper Dangaard Brouer
2019-05-10 16:23 ` David Howells
2019-05-10 16:50 ` Matthew Wilcox
2019-05-10 17:11 ` Christoph Hellwig
2019-05-10 17:35 ` Matthew Wilcox [this message]
2019-05-13 12:04 ` David Howells
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