path: root/virt
diff options
authorKristina Martsenko <kristina.martsenko@arm.com>2017-12-13 17:07:24 +0000
committerCatalin Marinas <catalin.marinas@arm.com>2017-12-22 17:37:33 +0000
commitfa2a8445b1d3810c52f2a6b3a006456bd1aacb7e (patch)
tree61ab6a749b01e7ad21b5a96ecf1be2011bc13223 /virt
parent75387b92635e7dca410c1ef92cfe510019248f76 (diff)
arm64: allow ID map to be extended to 52 bits
Currently, when using VA_BITS < 48, if the ID map text happens to be placed in physical memory above VA_BITS, we increase the VA size (up to 48) and create a new table level, in order to map in the ID map text. This is okay because the system always supports 48 bits of VA. This patch extends the code such that if the system supports 52 bits of VA, and the ID map text is placed that high up, then we increase the VA size accordingly, up to 52. One difference from the current implementation is that so far the condition of VA_BITS < 48 has meant that the top level table is always "full", with the maximum number of entries, and an extra table level is always needed. Now, when VA_BITS = 48 (and using 64k pages), the top level table is not full, and we simply need to increase the number of entries in it, instead of creating a new table level. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()] [catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'virt')
1 files changed, 8 insertions, 2 deletions
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index b36945d49986..761787befd3b 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -629,14 +629,20 @@ static int __create_hyp_mappings(pgd_t *pgdp,
pgd_t *pgd;
pud_t *pud;
- unsigned long addr, next;
+ unsigned long addr, next, ptrs_per_pgd = PTRS_PER_PGD;
int err = 0;
+ /*
+ * If it's not the hyp_pgd, fall back to the kvm idmap layout.
+ */
+ if (pgdp != hyp_pgd)
+ ptrs_per_pgd = __kvm_idmap_ptrs_per_pgd();
addr = start & PAGE_MASK;
end = PAGE_ALIGN(end);
do {
- pgd = pgdp + pgd_index(addr);
+ pgd = pgdp + ((addr >> PGDIR_SHIFT) & (ptrs_per_pgd - 1));
if (pgd_none(*pgd)) {
pud = pud_alloc_one(NULL, addr);