[PATCH RFC 03/17] arm64: provide cpu_replace_ttbr1_phys()

[Russell King (Oracle)]

Provide a version of cpu_replace_ttbr1_phys() which operates using a
physical address rather than the virtual address of the page tables.

Signed-off-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>
---
 arch/arm64/include/asm/mmu_context.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h
index 56911691bef0..4aa6afc6f935 100644
--- a/arch/arm64/include/asm/mmu_context.h
+++ b/arch/arm64/include/asm/mmu_context.h
@@ -148,7 +148,7 @@ static inline void cpu_install_ttbr0(phys_addr_t ttbr0, unsigned long t0sz)
  * Atomically replaces the active TTBR1_EL1 PGD with a new VA-compatible PGD,
  * avoiding the possibility of conflicting TLB entries being allocated.
  */
-static inline void cpu_replace_ttbr1(pgd_t *pgdp, pgd_t *idmap)
+static inline void cpu_replace_ttbr1_phys(phys_addr_t pgd_phys, pgd_t *idmap)
 {
 	typedef void (ttbr_replace_func)(phys_addr_t);
 	extern ttbr_replace_func idmap_cpu_replace_ttbr1;
@@ -156,9 +156,10 @@ static inline void cpu_replace_ttbr1(pgd_t *pgdp, pgd_t *idmap)
 	unsigned long daif;
 
 	/* phys_to_ttbr() zeros lower 2 bits of ttbr with 52-bit PA */
-	phys_addr_t ttbr1 = phys_to_ttbr(virt_to_phys(pgdp));
+	phys_addr_t ttbr1 = phys_to_ttbr(pgd_phys);
 
-	if (system_supports_cnp() && !WARN_ON(pgdp != lm_alias(swapper_pg_dir))) {
+	if (system_supports_cnp() &&
+	    !WARN_ON(pgd_phys != virt_to_phys(lm_alias(swapper_pg_dir)))) {
 		/*
 		 * cpu_replace_ttbr1() is used when there's a boot CPU
 		 * up (i.e. cpufeature framework is not up yet) and
@@ -185,6 +186,11 @@ static inline void cpu_replace_ttbr1(pgd_t *pgdp, pgd_t *idmap)
 	cpu_uninstall_idmap();
 }
 
+static inline void __nocfi cpu_replace_ttbr1(pgd_t *pgdp, pgd_t *idmap)
+{
+	cpu_replace_ttbr1_phys(virt_to_phys(pgdp), idmap);
+}
+
 /*
  * It would be nice to return ASIDs back to the allocator, but unfortunately
  * that introduces a race with a generation rollover where we could erroneously
-- 
2.30.2