From: will.deacon@arm•com (Will Deacon)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH V3 0/8] IOMMU probe deferral support
Date: Wed, 9 Nov 2016 16:59:49 +0000 [thread overview]
Message-ID: <20161109165949.GF17771@arm.com> (raw)
In-Reply-To: <002001d23a51$ecb01390$c6103ab0$@codeaurora.org>
On Wed, Nov 09, 2016 at 11:54:20AM +0530, Sricharan wrote:
> >> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> >> index 71ce4b6..a1d0b3c 100644
> >> --- a/drivers/iommu/arm-smmu.c
> >> +++ b/drivers/iommu/arm-smmu.c
> >> @@ -1516,8 +1516,10 @@ static struct iommu_group *arm_smmu_device_group(struct device *dev)
> >> group = smmu->s2crs[idx].group;
> >> }
> >>
> >> - if (group)
> >> + if (group) {
> >> + iommu_group_get_by_id(iommu_group_id(group));
> >> return group;
> >
> >This might as well just be inline, i.e.:
> >
> > return iommu_group_get_by_id(iommu_group_id(group));
> >
> >It's a shame we have to go all round the houses when we have the group
> >right there, but this is probably the most expedient fix. I guess we can
> >extend the API with some sort of iommu_group_get(group) overload in
> >future if we really want to.
> >
>
> ok, i can send this fix separately then. Otherwise, Will was suggesting on the
> other thread that there should probably be a separate API to increment
> the group refcount or get the group from the existing aliasing device.
> As per me adding the api, looks like another option or post the above ?
I think adding a new function to the API is the way to go -- having code
like what you propose above littered around the drivers is hard to read and
pretty error-prone, since it looks like a NOP to people who aren't already
thinking about ref counts.
Will
next prev parent reply other threads:[~2016-11-09 16:59 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20161004170414eucas1p141bebe16e1bf241862833e7ad0270c72@eucas1p1.samsung.com>
2016-10-04 17:03 ` [PATCH V3 0/8] IOMMU probe deferral support Sricharan R
2016-10-04 17:03 ` [PATCH V3 1/8] arm: dma-mapping: Don't override dma_ops in arch_setup_dma_ops() Sricharan R
2016-10-04 17:03 ` [PATCH V3 2/8] of: dma: Move range size workaround to of_dma_get_range() Sricharan R
2016-10-04 17:03 ` [PATCH V3 3/8] of: dma: Make of_dma_deconfigure() public Sricharan R
2016-10-04 17:03 ` [PATCH V3 4/8] drivers: platform: Configure dma operations at probe time Sricharan R
2016-10-26 14:07 ` Robin Murphy
2016-10-26 15:04 ` Sricharan
2016-10-27 10:49 ` Lorenzo Pieralisi
2016-11-02 7:05 ` Sricharan
2016-10-04 17:03 ` [PATCH V3 5/8] iommu: of: Handle IOMMU lookup failure with deferred probing or error Sricharan R
2016-10-26 14:52 ` Robin Murphy
2016-10-27 2:55 ` Sricharan
2016-10-04 17:03 ` [PATCH V3 6/8] arm: dma-mapping: Reset the device's dma_ops Sricharan R
2016-10-26 15:07 ` Robin Murphy
2016-10-27 3:37 ` Sricharan
2017-05-23 16:25 ` Russell King - ARM Linux
2017-05-23 16:55 ` Robin Murphy
2017-05-23 17:53 ` Russell King - ARM Linux
2017-05-23 21:46 ` Laurent Pinchart
2017-05-23 22:42 ` Russell King - ARM Linux
2017-05-24 10:31 ` Sricharan R
2017-05-24 11:26 ` Laurent Pinchart
2017-05-24 11:38 ` Sricharan R
2017-05-25 15:05 ` Russell King - ARM Linux
2017-05-26 5:18 ` Sricharan R
2017-05-26 14:04 ` Laurent Pinchart
2016-10-04 17:03 ` [PATCH V3 7/8] arm/arm64: dma-mapping: Call iommu's remove_device callback during device detach Sricharan R
2016-10-26 15:16 ` Robin Murphy
2016-10-27 5:16 ` Sricharan
2016-10-04 17:03 ` [PATCH V3 8/8] arm64: dma-mapping: Remove the notifier trick to handle early setting of dma_ops Sricharan R
2016-10-07 15:40 ` Sricharan
2016-10-26 15:34 ` Robin Murphy
2016-10-27 5:19 ` Sricharan
2016-10-10 12:36 ` [PATCH V3 0/8] IOMMU probe deferral support Marek Szyprowski
2016-10-12 6:24 ` Sricharan
2016-10-24 6:34 ` Marek Szyprowski
2016-10-24 12:30 ` Sricharan
2016-10-17 6:58 ` Sricharan
2016-10-17 7:02 ` Sricharan
2016-10-25 6:25 ` Archit Taneja
2016-10-25 14:35 ` Robin Murphy
2016-10-26 14:44 ` Sricharan
2016-10-26 17:14 ` Robin Murphy
2016-10-27 8:37 ` Sricharan
2016-11-03 22:25 ` Sricharan
2016-11-04 15:16 ` Sricharan
2016-11-07 19:13 ` Will Deacon
2016-11-07 19:22 ` Robin Murphy
2016-11-09 6:24 ` Sricharan
2016-11-09 16:59 ` Will Deacon [this message]
2016-11-14 3:41 ` Sricharan
2016-11-20 15:11 ` Sricharan
2016-11-23 19:54 ` Robin Murphy
2016-11-24 16:10 ` Sricharan
2016-11-24 19:11 ` Robin Murphy
2016-11-28 17:42 ` Sricharan
2016-11-28 18:13 ` Lorenzo Pieralisi
2016-11-30 0:34 ` Sricharan
2016-11-30 12:07 ` Lorenzo Pieralisi
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