| Message ID | 20180924004153.8232-16-digetx@gmail.com |
|---|---|
| State | Deferred |
| Headers | show |
| Series | IOMMU: Tegra GART driver clean up and optimization | expand |
On Mon, Sep 24, 2018 at 03:41:48AM +0300, Dmitry Osipenko wrote: > GART has a single address space that is shared by all devices, hence only > one domain could be active at a time. > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/iommu/tegra-gart.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c > index 1d45b023adea..9f7d3afb686f 100644 > --- a/drivers/iommu/tegra-gart.c > +++ b/drivers/iommu/tegra-gart.c > @@ -55,6 +55,7 @@ struct gart_device { > spinlock_t pte_lock; /* for pagetable */ > struct list_head client; > spinlock_t client_lock; /* for client list */ > + struct iommu_domain *active_domain; /* current active domain */ The active_ prefix seems a little unnecessary here, but either way: Acked-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c index 1d45b023adea..9f7d3afb686f 100644 --- a/drivers/iommu/tegra-gart.c +++ b/drivers/iommu/tegra-gart.c @@ -55,6 +55,7 @@ struct gart_device { spinlock_t pte_lock; /* for pagetable */ struct list_head client; spinlock_t client_lock; /* for client list */ + struct iommu_domain *active_domain; /* current active domain */ struct device *dev; struct iommu_device iommu; /* IOMMU Core handle */ @@ -184,6 +185,12 @@ static int gart_iommu_attach_dev(struct iommu_domain *domain, goto fail; } } + if (gart->active_domain && gart->active_domain != domain) { + dev_err(gart->dev, "Only one domain can be active at a time\n"); + err = -EINVAL; + goto fail; + } + gart->active_domain = domain; list_add(&client->list, &gart->client); spin_unlock(&gart->client_lock); dev_dbg(gart->dev, "Attached %s\n", dev_name(dev)); @@ -206,6 +213,8 @@ static void __gart_iommu_detach_dev(struct iommu_domain *domain, if (c->dev == dev) { list_del(&c->list); devm_kfree(gart->dev, c); + if (list_empty(&gart->client)) + gart->active_domain = NULL; dev_dbg(gart->dev, "Detached %s\n", dev_name(dev)); return; }
GART has a single address space that is shared by all devices, hence only one domain could be active at a time. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/iommu/tegra-gart.c | 9 +++++++++ 1 file changed, 9 insertions(+)