Moving to the VGIC implies giving access to some ioremapped
devices (the VGIC virtual interface control registers) to the
hypervisor.
Define create_hyp_io_mappings() as the IO aware sibling of
create_hyp_mappings(), and extend the mapping functions
to support a pte mapping backend.
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm/include/asm/kvm_mmu.h | 1 +
arch/arm/kvm/mmu.c | 76 ++++++++++++++++++++++++++++++----------
2 files changed, 58 insertions(+), 19 deletions(-)
diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index 7ccd259..422ec45 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -30,6 +30,7 @@
#define PGD2_ORDER get_order(PTRS_PER_PGD2 * sizeof(pgd_t))
int create_hyp_mappings(void *from, void *to);
+int create_hyp_io_mappings(void *from, void *to, phys_addr_t);
void free_hyp_pmds(void);
int kvm_alloc_stage2_pgd(struct kvm *kvm);
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 33d34ea..c37afd0 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -18,6 +18,7 @@
#include <linux/mman.h>
#include <linux/kvm_host.h>
+#include <linux/io.h>
#include <trace/events/kvm.h>
#include <asm/idmap.h>
#include <asm/pgalloc.h>
@@ -25,6 +26,7 @@
#include <asm/kvm_mmu.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
+#include <asm/mach/map.h>
#include "trace.h"
@@ -74,24 +76,43 @@ void free_hyp_pmds(void)
mutex_unlock(&kvm_hyp_pgd_mutex);
}
+/*
+ * Create a HYP pte mapping.
+ *
+ * If pfn_base is NULL, we map kernel pages into HYP with the virtual
+ * address. Otherwise, this is considered an I/O mapping and we map
+ * the physical region starting at *pfn_base to [start, end[.
+ */
static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
- unsigned long end)
+ unsigned long end, unsigned long *pfn_base)
{
pte_t *pte;
- struct page *page;
unsigned long addr;
+ pgprot_t prot;
+
+ if (pfn_base)
+ prot = __pgprot(get_mem_type_prot_pte(MT_DEVICE) | L_PTE_USER);
+ else
+ prot = PAGE_HYP;
for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
pte = pte_offset_kernel(pmd, addr);
- BUG_ON(!virt_addr_valid(addr));
- page = virt_to_page(addr);
+ if (pfn_base) {
+ BUG_ON(pfn_valid(*pfn_base));
+ set_pte_ext(pte, pfn_pte(*pfn_base, prot), 0);
+ (*pfn_base)++;
+ } else {
+ struct page *page;
+ BUG_ON(!virt_addr_valid(addr));
+ page = virt_to_page(addr);
+ set_pte_ext(pte, mk_pte(page, prot), 0);
+ }
- set_pte_ext(pte, mk_pte(page, PAGE_HYP), 0);
}
}
static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
- unsigned long end)
+ unsigned long end, unsigned long *pfn_base)
{
pmd_t *pmd;
pte_t *pte;
@@ -112,23 +133,13 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
}
next = pmd_addr_end(addr, end);
- create_hyp_pte_mappings(pmd, addr, next);
+ create_hyp_pte_mappings(pmd, addr, next, pfn_base);
}
return 0;
}
-/**
- * create_hyp_mappings - map a kernel virtual address range in Hyp mode
- * @from: The virtual kernel start address of the range
- * @to: The virtual kernel end address of the range (exclusive)
- *
- * The same virtual address as the kernel virtual address is also used in
- * Hyp-mode mapping to the same underlying physical pages.
- *
- * Note: Wrapping around zero in the "to" address is not supported.
- */
-int create_hyp_mappings(void *from, void *to)
+static int __create_hyp_mappings(void *from, void *to, unsigned long *pfn_base)
{
unsigned long start = (unsigned long)from;
unsigned long end = (unsigned long)to;
@@ -158,7 +169,7 @@ int create_hyp_mappings(void *from, void *to)
}
next = pgd_addr_end(addr, end);
- err = create_hyp_pmd_mappings(pud, addr, next);
+ err = create_hyp_pmd_mappings(pud, addr, next, pfn_base);
if (err)
goto out;
}
@@ -168,6 +179,33 @@ out:
}
/**
+ * create_hyp_mappings - map a kernel virtual address range in Hyp mode
+ * @from: The virtual kernel start address of the range
+ * @to: The virtual kernel end address of the range (exclusive)
+ *
+ * The same virtual address as the kernel virtual address is also used in
+ * Hyp-mode mapping to the same underlying physical pages.
+ *
+ * Note: Wrapping around zero in the "to" address is not supported.
+ */
+int create_hyp_mappings(void *from, void *to)
+{
+ return __create_hyp_mappings(from, to, NULL);
+}
+
+/**
+ * create_hyp_io_mappings - map a physical IO range in Hyp mode
+ * @from: The virtual HYP start address of the range
+ * @to: The virtual HYP end address of the range (exclusive)
+ * @addr: The physical start address which gets mapped
+ */
+int create_hyp_io_mappings(void *from, void *to, phys_addr_t addr)
+{
+ unsigned long pfn = __phys_to_pfn(addr);
+ return __create_hyp_mappings(from, to, &pfn);
+}
+
+/**
* kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
* @kvm: The KVM struct pointer for the VM.
*
--
1.7.10.3
