ARM: KVM: simplify HYP mapping population
The way we populate HYP mappings is a bit convoluted, to say the least.
Passing a pointer around to keep track of the current PFN is quite
odd, and we end-up having two different PTE accessors for no good
reason.
Simplify the whole thing by unifying the two PTE accessors, passing
a pgprot_t around, and moving the various validity checks to the
upper layers.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 2f12e40..3003321 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -125,54 +125,34 @@
}
static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
- unsigned long end)
-{
- pte_t *pte;
- unsigned long addr;
- struct page *page;
-
- for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
- unsigned long hyp_addr = KERN_TO_HYP(addr);
-
- pte = pte_offset_kernel(pmd, hyp_addr);
- BUG_ON(!virt_addr_valid(addr));
- page = virt_to_page(addr);
- kvm_set_pte(pte, mk_pte(page, PAGE_HYP));
- }
-}
-
-static void create_hyp_io_pte_mappings(pmd_t *pmd, unsigned long start,
- unsigned long end,
- unsigned long *pfn_base)
+ unsigned long end, unsigned long pfn,
+ pgprot_t prot)
{
pte_t *pte;
unsigned long addr;
- for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
- unsigned long hyp_addr = KERN_TO_HYP(addr);
-
- pte = pte_offset_kernel(pmd, hyp_addr);
- BUG_ON(pfn_valid(*pfn_base));
- kvm_set_pte(pte, pfn_pte(*pfn_base, PAGE_HYP_DEVICE));
- (*pfn_base)++;
+ for (addr = start; addr < end; addr += PAGE_SIZE) {
+ pte = pte_offset_kernel(pmd, addr);
+ kvm_set_pte(pte, pfn_pte(pfn, prot));
+ pfn++;
}
}
static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
- unsigned long end, unsigned long *pfn_base)
+ unsigned long end, unsigned long pfn,
+ pgprot_t prot)
{
pmd_t *pmd;
pte_t *pte;
unsigned long addr, next;
for (addr = start; addr < end; addr = next) {
- unsigned long hyp_addr = KERN_TO_HYP(addr);
- pmd = pmd_offset(pud, hyp_addr);
+ pmd = pmd_offset(pud, addr);
BUG_ON(pmd_sect(*pmd));
if (pmd_none(*pmd)) {
- pte = pte_alloc_one_kernel(NULL, hyp_addr);
+ pte = pte_alloc_one_kernel(NULL, addr);
if (!pte) {
kvm_err("Cannot allocate Hyp pte\n");
return -ENOMEM;
@@ -182,25 +162,17 @@
next = pmd_addr_end(addr, end);
- /*
- * 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[.
- */
- if (!pfn_base)
- create_hyp_pte_mappings(pmd, addr, next);
- else
- create_hyp_io_pte_mappings(pmd, addr, next, pfn_base);
+ create_hyp_pte_mappings(pmd, addr, next, pfn, prot);
+ pfn += (next - addr) >> PAGE_SHIFT;
}
return 0;
}
-static int __create_hyp_mappings(void *from, void *to, unsigned long *pfn_base)
+static int __create_hyp_mappings(pgd_t *pgdp,
+ unsigned long start, unsigned long end,
+ unsigned long pfn, pgprot_t prot)
{
- unsigned long start = (unsigned long)from;
- unsigned long end = (unsigned long)to;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
@@ -209,21 +181,14 @@
if (start >= end)
return -EINVAL;
- /* Check for a valid kernel memory mapping */
- if (!pfn_base && (!virt_addr_valid(from) || !virt_addr_valid(to - 1)))
- return -EINVAL;
- /* Check for a valid kernel IO mapping */
- if (pfn_base && (!is_vmalloc_addr(from) || !is_vmalloc_addr(to - 1)))
- return -EINVAL;
mutex_lock(&kvm_hyp_pgd_mutex);
- for (addr = start; addr < end; addr = next) {
- unsigned long hyp_addr = KERN_TO_HYP(addr);
- pgd = hyp_pgd + pgd_index(hyp_addr);
- pud = pud_offset(pgd, hyp_addr);
+ for (addr = start & PAGE_MASK; addr < end; addr = next) {
+ pgd = pgdp + pgd_index(addr);
+ pud = pud_offset(pgd, addr);
if (pud_none_or_clear_bad(pud)) {
- pmd = pmd_alloc_one(NULL, hyp_addr);
+ pmd = pmd_alloc_one(NULL, addr);
if (!pmd) {
kvm_err("Cannot allocate Hyp pmd\n");
err = -ENOMEM;
@@ -233,9 +198,10 @@
}
next = pgd_addr_end(addr, end);
- err = create_hyp_pmd_mappings(pud, addr, next, pfn_base);
+ err = create_hyp_pmd_mappings(pud, addr, next, pfn, prot);
if (err)
goto out;
+ pfn += (next - addr) >> PAGE_SHIFT;
}
out:
mutex_unlock(&kvm_hyp_pgd_mutex);
@@ -255,22 +221,38 @@
*/
int create_hyp_mappings(void *from, void *to)
{
- return __create_hyp_mappings(from, to, NULL);
+ unsigned long phys_addr = virt_to_phys(from);
+ unsigned long start = KERN_TO_HYP((unsigned long)from);
+ unsigned long end = KERN_TO_HYP((unsigned long)to);
+
+ /* Check for a valid kernel memory mapping */
+ if (!virt_addr_valid(from) || !virt_addr_valid(to - 1))
+ return -EINVAL;
+
+ return __create_hyp_mappings(hyp_pgd, start, end,
+ __phys_to_pfn(phys_addr), PAGE_HYP);
}
/**
* create_hyp_io_mappings - duplicate a kernel IO mapping into Hyp mode
* @from: The kernel start VA of the range
* @to: The kernel end VA of the range (exclusive)
- * @addr: The physical start address which gets mapped
+ * @phys_addr: The physical start address which gets mapped
*
* The resulting HYP VA is the same as the kernel VA, modulo
* HYP_PAGE_OFFSET.
*/
-int create_hyp_io_mappings(void *from, void *to, phys_addr_t addr)
+int create_hyp_io_mappings(void *from, void *to, phys_addr_t phys_addr)
{
- unsigned long pfn = __phys_to_pfn(addr);
- return __create_hyp_mappings(from, to, &pfn);
+ unsigned long start = KERN_TO_HYP((unsigned long)from);
+ unsigned long end = KERN_TO_HYP((unsigned long)to);
+
+ /* Check for a valid kernel IO mapping */
+ if (!is_vmalloc_addr(from) || !is_vmalloc_addr(to - 1))
+ return -EINVAL;
+
+ return __create_hyp_mappings(hyp_pgd, start, end,
+ __phys_to_pfn(phys_addr), PAGE_HYP_DEVICE);
}
/**