From: Nicolin Chen <nicolinc@nvidia.com>
To: "Tian, Kevin" <kevin.tian@intel.com>
Cc: "jgg@nvidia.com" <jgg@nvidia.com>,
"Liu, Yi L" <yi.l.liu@intel.com>,
"joro@8bytes.org" <joro@8bytes.org>,
"will@kernel.org" <will@kernel.org>,
"robin.murphy@arm.com" <robin.murphy@arm.com>,
"alex.williamson@redhat.com" <alex.williamson@redhat.com>,
"shuah@kernel.org" <shuah@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"iommu@lists.linux.dev" <iommu@lists.linux.dev>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
"linux-kselftest@vger.kernel.org"
<linux-kselftest@vger.kernel.org>,
"mjrosato@linux.ibm.com" <mjrosato@linux.ibm.com>,
"farman@linux.ibm.com" <farman@linux.ibm.com>
Subject: Re: [PATCH v10 3/6] iommufd: Add iommufd_access_change_ioas(_id) helpers
Date: Thu, 27 Jul 2023 21:44:14 -0700 [thread overview]
Message-ID: <ZMNHnmydMM1zExZW@Asurada-Nvidia> (raw)
In-Reply-To: <BN9PR11MB5276C3F296F27696AFD92D0F8C06A@BN9PR11MB5276.namprd11.prod.outlook.com>
On Fri, Jul 28, 2023 at 04:41:18AM +0000, Tian, Kevin wrote:
> > From: Nicolin Chen <nicolinc@nvidia.com>
> > Sent: Friday, July 28, 2023 12:37 PM
> >
> > On Fri, Jul 28, 2023 at 04:23:03AM +0000, Tian, Kevin wrote:
> > > > From: Nicolin Chen <nicolinc@nvidia.com>
> > > > Sent: Friday, July 28, 2023 4:25 AM
> > > >
> > > > +static int iommufd_access_change_ioas(struct iommufd_access *access,
> > > > + struct iommufd_ioas *new_ioas)
> > > > +{
> > > > + u32 iopt_access_list_id = access->iopt_access_list_id;
> > > > + struct iommufd_ioas *cur_ioas = access->ioas;
> > > > + int rc;
> > > > +
> > > > + lockdep_assert_held(&access->ioas_lock);
> > > > +
> > > > + /* We are racing with a concurrent detach, bail */
> > > > + if (cur_ioas != access->ioas_unpin)
> > > > + return -EBUSY;
> > > > +
> > > > + if (IS_ERR(new_ioas))
> > > > + return PTR_ERR(new_ioas);
> > >
> > > iommufd_access_change_ioas_id() already checks errors.
> >
> > I've thought about that: given that iommufd_access_change_ioas
> > is a standalone API, though it's not used anywhere else at the
> > moment, it might be safer to have this check again. Otherwise,
> > we would need a line of comments saying that "caller must make
> > sure that the input new_ioas is not holding an error code" or
> > so?
> >
>
> I don't think it's a common practice for the caller to pass in
> an error pointer when it already knows it's an error...
OK. I will just drop it then.
next prev parent reply other threads:[~2023-07-28 4:44 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-27 20:24 [PATCH v10 0/6] Add IO page table replacement support Nicolin Chen
2023-07-27 20:24 ` [PATCH v10 1/6] vfio: Do not allow !ops->dma_unmap in vfio_pin/unpin_pages() Nicolin Chen
2023-07-27 20:24 ` [PATCH v10 2/6] iommufd: Allow passing in iopt_access_list_id to iopt_remove_access() Nicolin Chen
2023-07-28 4:18 ` Tian, Kevin
2023-07-27 20:24 ` [PATCH v10 3/6] iommufd: Add iommufd_access_change_ioas(_id) helpers Nicolin Chen
2023-07-28 4:23 ` Tian, Kevin
2023-07-28 4:36 ` Nicolin Chen
2023-07-28 4:41 ` Tian, Kevin
2023-07-28 4:44 ` Nicolin Chen [this message]
2023-07-27 20:24 ` [PATCH v10 4/6] iommufd: Add iommufd_access_replace() API Nicolin Chen
2023-07-28 4:23 ` Tian, Kevin
2023-07-27 20:24 ` [PATCH v10 5/6] iommufd/selftest: Add IOMMU_TEST_OP_ACCESS_REPLACE_IOAS coverage Nicolin Chen
2023-07-27 20:24 ` [PATCH v10 6/6] vfio: Support IO page table replacement Nicolin Chen
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=ZMNHnmydMM1zExZW@Asurada-Nvidia \
--to=nicolinc@nvidia.com \
--cc=alex.williamson@redhat.com \
--cc=farman@linux.ibm.com \
--cc=iommu@lists.linux.dev \
--cc=jgg@nvidia.com \
--cc=joro@8bytes.org \
--cc=kevin.tian@intel.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=mjrosato@linux.ibm.com \
--cc=robin.murphy@arm.com \
--cc=shuah@kernel.org \
--cc=will@kernel.org \
--cc=yi.l.liu@intel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.