iommu/core: pass a user-provided token to fault handlers
Sometimes a single IOMMU user may have to deal with several
different IOMMU devices (e.g. remoteproc).
When an IOMMU fault happens, such users have to regain their
context in order to deal with the fault.
Users can't use the private fields of neither the iommu_domain nor
the IOMMU device, because those are already used by the IOMMU core
and low level driver (respectively).
This patch just simply allows users to pass a private token (most
notably their own context pointer) to iommu_set_fault_handler(),
and then makes sure it is provided back to the users whenever
an IOMMU fault happens.
The patch also adopts remoteproc to the new fault handling
interface, but the real functionality using this (recovery of
remote processors) will only be added later in a subsequent patch
set.
Cc: Fernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index d937580..450293f 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -35,12 +35,13 @@
#define IOMMU_FAULT_WRITE 0x1
typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
- struct device *, unsigned long, int);
+ struct device *, unsigned long, int, void *);
struct iommu_domain {
struct iommu_ops *ops;
void *priv;
iommu_fault_handler_t handler;
+ void *handler_token;
};
#define IOMMU_CAP_CACHE_COHERENCY 0x1
@@ -95,7 +96,7 @@
extern int iommu_domain_has_cap(struct iommu_domain *domain,
unsigned long cap);
extern void iommu_set_fault_handler(struct iommu_domain *domain,
- iommu_fault_handler_t handler);
+ iommu_fault_handler_t handler, void *token);
extern int iommu_device_group(struct device *dev, unsigned int *groupid);
/**
@@ -132,7 +133,8 @@
* invoke it.
*/
if (domain->handler)
- ret = domain->handler(domain, dev, iova, flags);
+ ret = domain->handler(domain, dev, iova, flags,
+ domain->handler_token);
return ret;
}
@@ -191,7 +193,7 @@
}
static inline void iommu_set_fault_handler(struct iommu_domain *domain,
- iommu_fault_handler_t handler)
+ iommu_fault_handler_t handler, void *token)
{
}