public inbox for linux-s390@vger.kernel.org
 help / color / mirror / Atom feed
From: Matthew Rosato <mjrosato@linux.ibm.com>
To: Niklas Schnelle <schnelle@linux.ibm.com>,
	joro@8bytes.org, will@kernel.org, robin.murphy@arm.com,
	gerald.schaefer@linux.ibm.com
Cc: hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com,
	svens@linux.ibm.com, borntraeger@linux.ibm.com,
	farman@linux.ibm.com, clegoate@redhat.com, iommu@lists.linux.dev,
	linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Subject: Re: [PATCH v2 2/3] s390/pci: store DMA offset in bus_dma_region
Date: Mon, 16 Dec 2024 11:51:58 -0500	[thread overview]
Message-ID: <ddebeba2-e32c-4c00-8107-4f4e3850c477@linux.ibm.com> (raw)
In-Reply-To: <d2d6c27d12a5d7770952a9c027d290204c4fac6d.camel@linux.ibm.com>


>>> +	map->cpu_start = 0;
>>> +	map->dma_start = PAGE_ALIGN(zdev->start_dma);
>>> +	map->size = (u64)virt_to_phys(high_memory);
>>
>> I don't think we should restrict the size here to the size of memory.
>> Instead I think it should be zdev->end_dma - zdev->start_dma.
>>
>> Since we handle the restriction to memory size as reserved regions I
>> think that should be compatible. Also I think otherwise this might
>> break the admittedly odd s390_iommu_aperture=X kernel parameter on
>> LPARs.
> 
> Correction, zdev->end_dma - zdev->start_dma + 1 because zdev->end_dma
> is inclusive ;-)
> 

Forgot about that parameter, thanks...  OK, will change to:

map->size = zdev->end_dma - zdev->start_dma + 1;

  reply	other threads:[~2024-12-16 16:52 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-12-13 22:49 [PATCH v2 0/3] iommu/s390: add support for IOMMU passthrough Matthew Rosato
2024-12-13 22:49 ` [PATCH v2 1/3] s390/pci: check for relaxed translation capability Matthew Rosato
2024-12-13 22:49 ` [PATCH v2 2/3] s390/pci: store DMA offset in bus_dma_region Matthew Rosato
2024-12-16  9:29   ` Niklas Schnelle
2024-12-16 10:18     ` Niklas Schnelle
2024-12-16 16:51       ` Matthew Rosato [this message]
2024-12-13 22:49 ` [PATCH v2 3/3] iommu/s390: implement iommu passthrough via identity domain Matthew Rosato

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=ddebeba2-e32c-4c00-8107-4f4e3850c477@linux.ibm.com \
    --to=mjrosato@linux.ibm.com \
    --cc=agordeev@linux.ibm.com \
    --cc=borntraeger@linux.ibm.com \
    --cc=clegoate@redhat.com \
    --cc=farman@linux.ibm.com \
    --cc=gerald.schaefer@linux.ibm.com \
    --cc=gor@linux.ibm.com \
    --cc=hca@linux.ibm.com \
    --cc=iommu@lists.linux.dev \
    --cc=joro@8bytes.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=schnelle@linux.ibm.com \
    --cc=svens@linux.ibm.com \
    --cc=will@kernel.org \
    /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