From: Christoph Hellwig <hch@lst.de>
To: Robin Murphy <robin.murphy@arm.com>
Cc: David Rientjes <rientjes@google.com>,
Christoph Hellwig <hch@lst.de>,
"Lendacky, Thomas" <Thomas.Lendacky@amd.com>,
"Singh, Brijesh" <brijesh.singh@amd.com>,
"Grimm, Jon" <jon.grimm@amd.com>,
baekhw@google.com,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"iommu@lists.linux-foundation.org"
<iommu@lists.linux-foundation.org>
Subject: Re: [rfc] dma-mapping: preallocate unencrypted DMA atomic pool
Date: Tue, 7 Jan 2020 11:54:58 +0100 [thread overview]
Message-ID: <20200107105458.GA3139@lst.de> (raw)
In-Reply-To: <3213a6ac-5aad-62bc-bf95-fae8ba088b9e@arm.com>
On Mon, Jan 06, 2020 at 05:34:00PM +0000, Robin Murphy wrote:
> On 01/01/2020 1:54 am, David Rientjes via iommu wrote:
>> Christoph, Thomas, is something like this (without the diagnosic
>> information included in this patch) acceptable for these allocations?
>> Adding expansion support when the pool is half depleted wouldn't be *that*
>> hard.
>>
>> Or are there alternatives we should consider? Thanks!
>
> Are there any platforms which require both non-cacheable remapping *and*
> unencrypted remapping for distinct subsets of devices?
>
> If not (and I'm assuming there aren't, because otherwise this patch is
> incomplete in covering only 2 of the 3 possible combinations), then
> couldn't we keep things simpler by just attributing both properties to the
> single "atomic pool" on the basis that one or the other will always be a
> no-op? In other words, basically just tweaking the existing "!coherent"
> tests to "!coherent || force_dma_unencrypted()" and doing
> set_dma_unencrypted() unconditionally in atomic_pool_init().
I think that would make most sense.
next prev parent reply other threads:[~2020-01-07 10:55 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-01 1:54 [rfc] dma-mapping: preallocate unencrypted DMA atomic pool David Rientjes
2020-01-06 17:34 ` Robin Murphy
2020-01-07 10:54 ` Christoph Hellwig [this message]
2020-01-07 19:57 ` David Rientjes
2020-01-09 14:31 ` Christoph Hellwig
2020-01-09 18:58 ` David Rientjes
2020-01-17 15:28 ` Tom Lendacky
2020-02-28 9:27 ` David Rientjes
2020-03-02 0:05 ` [rfc 0/6] unencrypted atomic DMA pools with dynamic expansion David Rientjes
2020-03-02 0:05 ` [rfc 1/6] dma-mapping: pass device to atomic allocation functions David Rientjes
2020-03-02 0:05 ` [rfc 2/6] dma-remap: add additional atomic pools to map to gfp mask David Rientjes
2020-03-05 15:42 ` Christoph Hellwig
2020-03-02 0:05 ` [rfc 3/6] dma-remap: wire up the atomic pools depending on " David Rientjes
2020-03-05 15:43 ` Christoph Hellwig
2020-03-02 0:05 ` [rfc 4/6] dma-remap: dynamically expanding atomic pools David Rientjes
2020-03-03 22:29 ` David Rientjes
2020-03-02 0:05 ` [rfc 5/6] dma-direct: atomic allocations must come from unencrypted pools David Rientjes
2020-03-05 15:44 ` Christoph Hellwig
2020-03-07 0:36 ` David Rientjes
2020-03-10 18:47 ` Christoph Hellwig
2020-03-02 0:05 ` [rfc 6/6] dma-remap: double the default DMA coherent pool size David Rientjes
2020-03-05 15:45 ` Christoph Hellwig
2020-04-08 21:21 ` [rfc v2 0/6] unencrypted atomic DMA pools with dynamic expansion David Rientjes
2020-04-08 21:21 ` [rfc v2 1/6] dma-remap: separate DMA atomic pools from direct remap code David Rientjes
2020-04-14 6:35 ` Christoph Hellwig
2020-04-08 21:21 ` [rfc v2 2/6] dma-pool: add additional coherent pools to map to gfp mask David Rientjes
2020-04-08 21:21 ` [rfc v2 3/6] dma-pool: dynamically expanding atomic pools David Rientjes
2020-04-08 21:21 ` [rfc v2 4/6] dma-direct: atomic allocations must come from atomic coherent pools David Rientjes
2020-04-09 21:24 ` Tom Lendacky
2020-04-14 19:18 ` David Rientjes
2020-04-14 6:43 ` Christoph Hellwig
2020-04-14 19:20 ` David Rientjes
2020-04-08 21:21 ` [rfc v2 5/6] x86/mm: unencrypted non-blocking DMA allocations use " David Rientjes
2020-04-08 21:21 ` [rfc v2 6/6] dma-pool: scale the default DMA coherent pool size with memory capacity David Rientjes
[not found] ` <20200410145520.17864-1-hdanton@sina.com>
2020-04-10 19:37 ` [rfc v2 3/6] dma-pool: dynamically expanding atomic pools David Rientjes
2020-04-14 6:44 ` Christoph Hellwig
2020-04-14 19:23 ` David Rientjes
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200107105458.GA3139@lst.de \
--to=hch@lst.de \
--cc=Thomas.Lendacky@amd.com \
--cc=baekhw@google.com \
--cc=brijesh.singh@amd.com \
--cc=iommu@lists.linux-foundation.org \
--cc=jon.grimm@amd.com \
--cc=linux-kernel@vger.kernel.org \
--cc=rientjes@google.com \
--cc=robin.murphy@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).