s390/tlb: Convert MACHINE_HAS_TLB_GUEST to machine_has_tlb_guest()

Use static branch(es) to implement and use machine_has_tlb_guest()
instead of a runtime check via MACHINE_HAS_TLB_GUEST.

Also add sclp_early_detect_machine_features() in order to allow for
feature detection from the decompressor.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

10 files changed, 30 insertions, 15 deletions

diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 1c7367a338cd..4ef2622f3d30 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -482,6 +482,7 @@ void startup_kernel(void)
 
 	read_ipl_report();
 	sclp_early_read_info();
+	sclp_early_detect_machine_features();
 	detect_facilities();
 	cmma_init();
 	sanitize_prot_virt_host();
diff --git a/arch/s390/include/asm/machine.h b/arch/s390/include/asm/machine.h
index e0a0e4121d08..33cb4403fc82 100644
--- a/arch/s390/include/asm/machine.h
+++ b/arch/s390/include/asm/machine.h
@@ -11,6 +11,7 @@
 #define MFEATURE_LOWCORE	0
 #define MFEATURE_PCI_MIO	1
 #define MFEATURE_SCC		2
+#define MFEATURE_TLB_GUEST	3
 
 #ifndef __ASSEMBLY__
 
@@ -80,6 +81,7 @@ static __always_inline bool machine_has_##name(void)				\
 
 DEFINE_MACHINE_HAS_FEATURE(relocated_lowcore, MFEATURE_LOWCORE)
 DEFINE_MACHINE_HAS_FEATURE(scc, MFEATURE_SCC)
+DEFINE_MACHINE_HAS_FEATURE(tlb_guest, MFEATURE_TLB_GUEST)
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_S390_MACHINE_H */
diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index 18f37dff03c9..1e62919bacf4 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -168,6 +168,7 @@ int sclp_early_read_storage_info(void);
 int sclp_early_get_core_info(struct sclp_core_info *info);
 void sclp_early_get_ipl_info(struct sclp_ipl_info *info);
 void sclp_early_detect(void);
+void sclp_early_detect_machine_features(void);
 void sclp_early_printk(const char *s);
 void __sclp_early_printk(const char *s, unsigned int len);
 void sclp_emergency_printk(const char *s);
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index b1f6ea1e000a..bb9d701ec9a6 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -23,7 +23,6 @@
 #define MACHINE_FLAG_DIAG9C	BIT(3)
 #define MACHINE_FLAG_ESOP	BIT(4)
 #define MACHINE_FLAG_TE		BIT(11)
-#define MACHINE_FLAG_TLB_GUEST	BIT(14)
 
 #define LPP_MAGIC		BIT(31)
 #define LPP_PID_MASK		_AC(0xffffffff, UL)
@@ -74,7 +73,6 @@ extern unsigned long mio_wb_bit_mask;
 #define MACHINE_HAS_DIAG9C	(get_lowcore()->machine_flags & MACHINE_FLAG_DIAG9C)
 #define MACHINE_HAS_ESOP	(get_lowcore()->machine_flags & MACHINE_FLAG_ESOP)
 #define MACHINE_HAS_TE		(get_lowcore()->machine_flags & MACHINE_FLAG_TE)
-#define MACHINE_HAS_TLB_GUEST	(get_lowcore()->machine_flags & MACHINE_FLAG_TLB_GUEST)
 
 /*
  * Console mode. Override with conmode=
diff --git a/arch/s390/include/asm/tlbflush.h b/arch/s390/include/asm/tlbflush.h
index 4a062317ca71..75491baa2197 100644
--- a/arch/s390/include/asm/tlbflush.h
+++ b/arch/s390/include/asm/tlbflush.h
@@ -6,6 +6,7 @@
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <asm/processor.h>
+#include <asm/machine.h>
 
 /*
  * Flush all TLB entries on the local CPU.
@@ -23,7 +24,7 @@ static inline void __tlb_flush_idte(unsigned long asce)
 	unsigned long opt;
 
 	opt = IDTE_PTOA;
-	if (MACHINE_HAS_TLB_GUEST)
+	if (machine_has_tlb_guest())
 		opt |= IDTE_GUEST_ASCE;
 	/* Global TLB flush for the mm */
 	asm volatile("idte 0,%1,%0" : : "a" (opt), "a" (asce) : "cc");
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 703a6594cfaf..df21ea6fbd59 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -37,6 +37,7 @@
 #include <asm/access-regs.h>
 #include <asm/asm-offsets.h>
 #include <asm/lowcore.h>
+#include <asm/machine.h>
 #include <asm/stp.h>
 #include <asm/gmap.h>
 #include <asm/nmi.h>
@@ -3397,7 +3398,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	/* we emulate STHYI in kvm */
 	set_kvm_facility(kvm->arch.model.fac_mask, 74);
 	set_kvm_facility(kvm->arch.model.fac_list, 74);
-	if (MACHINE_HAS_TLB_GUEST) {
+	if (machine_has_tlb_guest()) {
 		set_kvm_facility(kvm->arch.model.fac_mask, 147);
 		set_kvm_facility(kvm->arch.model.fac_list, 147);
 	}
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 7a2f5effd626..0d7cce4f3e83 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -21,6 +21,7 @@
 #include <linux/pgtable.h>
 #include <asm/page-states.h>
 #include <asm/pgalloc.h>
+#include <asm/machine.h>
 #include <asm/gmap.h>
 #include <asm/page.h>
 #include <asm/tlb.h>
@@ -2026,7 +2027,7 @@ static void gmap_pmdp_xchg(struct gmap *gmap, pmd_t *pmdp, pmd_t new,
 	gaddr &= HPAGE_MASK;
 	pmdp_notify_gmap(gmap, pmdp, gaddr);
 	new = clear_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_GMAP_IN));
-	if (MACHINE_HAS_TLB_GUEST)
+	if (machine_has_tlb_guest())
 		__pmdp_idte(gaddr, (pmd_t *)pmdp, IDTE_GUEST_ASCE, gmap->asce,
 			    IDTE_GLOBAL);
 	else if (cpu_has_idte())
@@ -2104,7 +2105,7 @@ void gmap_pmdp_idte_local(struct mm_struct *mm, unsigned long vmaddr)
 			WARN_ON(pmd_val(*pmdp) & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE |
 						   _SEGMENT_ENTRY_GMAP_UC |
 						   _SEGMENT_ENTRY));
-			if (MACHINE_HAS_TLB_GUEST)
+			if (machine_has_tlb_guest())
 				__pmdp_idte(gaddr, pmdp, IDTE_GUEST_ASCE,
 					    gmap->asce, IDTE_LOCAL);
 			else if (cpu_has_idte())
@@ -2137,7 +2138,7 @@ void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr)
 			WARN_ON(pmd_val(*pmdp) & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE |
 						   _SEGMENT_ENTRY_GMAP_UC |
 						   _SEGMENT_ENTRY));
-			if (MACHINE_HAS_TLB_GUEST)
+			if (machine_has_tlb_guest())
 				__pmdp_idte(gaddr, pmdp, IDTE_GUEST_ASCE,
 					    gmap->asce, IDTE_GLOBAL);
 			else if (cpu_has_idte())
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index ee3c4fec5055..f6712781d8a1 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -24,6 +24,7 @@
 #include <asm/tlbflush.h>
 #include <asm/mmu_context.h>
 #include <asm/page-states.h>
+#include <asm/machine.h>
 
 pgprot_t pgprot_writecombine(pgprot_t prot)
 {
@@ -50,7 +51,7 @@ static inline void ptep_ipte_local(struct mm_struct *mm, unsigned long addr,
 {
 	unsigned long opt, asce;
 
-	if (MACHINE_HAS_TLB_GUEST) {
+	if (machine_has_tlb_guest()) {
 		opt = 0;
 		asce = READ_ONCE(mm->context.gmap_asce);
 		if (asce == 0UL || nodat)
@@ -70,7 +71,7 @@ static inline void ptep_ipte_global(struct mm_struct *mm, unsigned long addr,
 {
 	unsigned long opt, asce;
 
-	if (MACHINE_HAS_TLB_GUEST) {
+	if (machine_has_tlb_guest()) {
 		opt = 0;
 		asce = READ_ONCE(mm->context.gmap_asce);
 		if (asce == 0UL || nodat)
@@ -375,7 +376,7 @@ void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
 static inline void pmdp_idte_local(struct mm_struct *mm,
 				   unsigned long addr, pmd_t *pmdp)
 {
-	if (MACHINE_HAS_TLB_GUEST)
+	if (machine_has_tlb_guest())
 		__pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE,
 			    mm->context.asce, IDTE_LOCAL);
 	else
@@ -387,7 +388,7 @@ static inline void pmdp_idte_local(struct mm_struct *mm,
 static inline void pmdp_idte_global(struct mm_struct *mm,
 				    unsigned long addr, pmd_t *pmdp)
 {
-	if (MACHINE_HAS_TLB_GUEST) {
+	if (machine_has_tlb_guest()) {
 		__pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE,
 			    mm->context.asce, IDTE_GLOBAL);
 		if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
@@ -506,7 +507,7 @@ EXPORT_SYMBOL(pmdp_xchg_lazy);
 static inline void pudp_idte_local(struct mm_struct *mm,
 				   unsigned long addr, pud_t *pudp)
 {
-	if (MACHINE_HAS_TLB_GUEST)
+	if (machine_has_tlb_guest())
 		__pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
 			    mm->context.asce, IDTE_LOCAL);
 	else
@@ -516,7 +517,7 @@ static inline void pudp_idte_local(struct mm_struct *mm,
 static inline void pudp_idte_global(struct mm_struct *mm,
 				    unsigned long addr, pud_t *pudp)
 {
-	if (MACHINE_HAS_TLB_GUEST)
+	if (machine_has_tlb_guest())
 		__pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
 			    mm->context.asce, IDTE_GLOBAL);
 	else if (cpu_has_idte())
diff --git a/drivers/s390/char/sclp_early.c b/drivers/s390/char/sclp_early.c
index d9d6edaf8de8..fc83f157c4e4 100644
--- a/drivers/s390/char/sclp_early.c
+++ b/drivers/s390/char/sclp_early.c
@@ -52,8 +52,6 @@ static void __init sclp_early_facilities_detect(void)
 	sclp.has_zpci_lsi = !!(sccb->fac118 & 0x01);
 	if (sccb->fac85 & 0x02)
 		get_lowcore()->machine_flags |= MACHINE_FLAG_ESOP;
-	if (sccb->fac91 & 0x40)
-		get_lowcore()->machine_flags |= MACHINE_FLAG_TLB_GUEST;
 	sclp.has_diag204_bif = !!(sccb->fac98 & 0x80);
 	sclp.has_diag310 = !!(sccb->fac91 & 0x80);
 	if (sccb->cpuoff > 134) {
diff --git a/drivers/s390/char/sclp_early_core.c b/drivers/s390/char/sclp_early_core.c
index 5a5383cceb6f..d03ad01082d0 100644
--- a/drivers/s390/char/sclp_early_core.c
+++ b/drivers/s390/char/sclp_early_core.c
@@ -13,6 +13,7 @@
 #include <asm/sections.h>
 #include <asm/physmem_info.h>
 #include <asm/facility.h>
+#include <asm/machine.h>
 #include "sclp.h"
 #include "sclp_rw.h"
 
@@ -335,6 +336,16 @@ int __init sclp_early_get_hsa_size(unsigned long *hsa_size)
 	return 0;
 }
 
+void __init sclp_early_detect_machine_features(void)
+{
+	struct read_info_sccb *sccb = &sclp_info_sccb;
+
+	if (!sclp_info_sccb_valid)
+		return;
+	if (sccb->fac91 & 0x40)
+		set_machine_feature(MFEATURE_TLB_GUEST);
+}
+
 #define SCLP_STORAGE_INFO_FACILITY     0x0000400000000000UL
 
 void __weak __init add_physmem_online_range(u64 start, u64 end) {}