From 3562c76dcb9ce84853c835eec12a911bf3a8e2da Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 12 Apr 2013 19:12:02 +0100 Subject: ARM: KVM: fix HYP mapping limitations around zero The current code for creating HYP mapping doesn't like to wrap around zero, which prevents from mapping anything into the last page of the virtual address space. It doesn't take much effort to remove this limitation, making the code more consistent with the rest of the kernel in the process. Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/mmu.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) (limited to 'arch/arm/kvm/mmu.c') diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 30033219df8..96d61daa23b 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -131,11 +131,12 @@ static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start, pte_t *pte; unsigned long addr; - for (addr = start; addr < end; addr += PAGE_SIZE) { + addr = start; + do { pte = pte_offset_kernel(pmd, addr); kvm_set_pte(pte, pfn_pte(pfn, prot)); pfn++; - } + } while (addr += PAGE_SIZE, addr != end); } static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start, @@ -146,7 +147,8 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start, pte_t *pte; unsigned long addr, next; - for (addr = start; addr < end; addr = next) { + addr = start; + do { pmd = pmd_offset(pud, addr); BUG_ON(pmd_sect(*pmd)); @@ -164,7 +166,7 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start, create_hyp_pte_mappings(pmd, addr, next, pfn, prot); pfn += (next - addr) >> PAGE_SHIFT; - } + } while (addr = next, addr != end); return 0; } @@ -179,11 +181,10 @@ static int __create_hyp_mappings(pgd_t *pgdp, unsigned long addr, next; int err = 0; - if (start >= end) - return -EINVAL; - mutex_lock(&kvm_hyp_pgd_mutex); - for (addr = start & PAGE_MASK; addr < end; addr = next) { + addr = start & PAGE_MASK; + end = PAGE_ALIGN(end); + do { pgd = pgdp + pgd_index(addr); pud = pud_offset(pgd, addr); @@ -202,7 +203,7 @@ static int __create_hyp_mappings(pgd_t *pgdp, if (err) goto out; pfn += (next - addr) >> PAGE_SHIFT; - } + } while (addr = next, addr != end); out: mutex_unlock(&kvm_hyp_pgd_mutex); return err; @@ -216,8 +217,6 @@ out: * The same virtual address as the kernel virtual address is also used * in Hyp-mode mapping (modulo HYP_PAGE_OFFSET) 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) { -- cgit v1.2.3