@@ -367,6 +367,10 @@ static inline int first_pte_in_page(struct dma_pte *pte)
* do the same thing as crashdump kernel.
*/
+static struct context_entry *device_to_existing_context_entry(
+ struct intel_iommu *iommu,
+ u8 bus, u8 devfn);
+
/*
* This domain is a statically identity mapping domain.
@@ -4810,3 +4814,22 @@ static void __init check_tylersburg_isoch(void)
printk(KERN_WARNING "DMAR: Recommended TLB entries for ISOCH unit is 16; your BIOS set %d\n",
vtisochctrl);
}
+
+static struct context_entry *device_to_existing_context_entry(
+ struct intel_iommu *iommu,
+ u8 bus, u8 devfn)
+{
+ struct root_entry *root;
+ struct context_entry *context;
+ struct context_entry *ret = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+ root = &iommu->root_entry[bus];
+ context = get_context_addr_from_root(root);
+ if (context && context_present(context+devfn))
+ ret = &context[devfn];
+ spin_unlock_irqrestore(&iommu->lock, flags);
+ return ret;
+}
+
Interface for when a new domain in the old kernel needs some values from the panicked kernel's context entries. Signed-off-by: Li, Zhen-Hua <zhen-hual@hp.com> --- drivers/iommu/intel-iommu.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)