6 files changed, 132 insertions, 43 deletions

diff --git a/arch/powerpc/include/asm/nohash/32/kup-8xx.h b/arch/powerpc/include/asm/nohash/32/kup-8xx.h
index 882a0bc7887a..c44d97751723 100644
--- a/arch/powerpc/include/asm/nohash/32/kup-8xx.h
+++ b/arch/powerpc/include/asm/nohash/32/kup-8xx.h
@@ -20,11 +20,12 @@ static __always_inline bool kuap_is_disabled(void)
 	return static_branch_unlikely(&disable_kuap_key);
 }
 
-static inline void kuap_save_and_lock(struct pt_regs *regs)
+static inline void __kuap_lock(void)
 {
-	if (kuap_is_disabled())
-		return;
+}
 
+static inline void __kuap_save_and_lock(struct pt_regs *regs)
+{
 	regs->kuap = mfspr(SPRN_MD_AP);
 	mtspr(SPRN_MD_AP, MD_APG_KUAP);
 }
@@ -33,21 +34,15 @@ static inline void kuap_user_restore(struct pt_regs *regs)
 {
 }
 
-static inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap)
+static inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap)
 {
-	if (kuap_is_disabled())
-		return;
-
 	mtspr(SPRN_MD_AP, regs->kuap);
 }
 
-static inline unsigned long kuap_get_and_assert_locked(void)
+static inline unsigned long __kuap_get_and_assert_locked(void)
 {
 	unsigned long kuap;
 
-	if (kuap_is_disabled())
-		return MD_APG_INIT;
-
 	kuap = mfspr(SPRN_MD_AP);
 
 	if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG))
@@ -56,36 +51,21 @@ static inline unsigned long kuap_get_and_assert_locked(void)
 	return kuap;
 }
 
-static inline void kuap_assert_locked(void)
-{
-	if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) && !kuap_is_disabled())
-		kuap_get_and_assert_locked();
-}
-
-static inline void allow_user_access(void __user *to, const void __user *from,
-				     unsigned long size, unsigned long dir)
+static inline void __allow_user_access(void __user *to, const void __user *from,
+				       unsigned long size, unsigned long dir)
 {
-	if (kuap_is_disabled())
-		return;
-
 	mtspr(SPRN_MD_AP, MD_APG_INIT);
 }
 
-static inline void prevent_user_access(unsigned long dir)
+static inline void __prevent_user_access(unsigned long dir)
 {
-	if (kuap_is_disabled())
-		return;
-
 	mtspr(SPRN_MD_AP, MD_APG_KUAP);
 }
 
-static inline unsigned long prevent_user_access_return(void)
+static inline unsigned long __prevent_user_access_return(void)
 {
 	unsigned long flags;
 
-	if (kuap_is_disabled())
-		return MD_APG_INIT;
-
 	flags = mfspr(SPRN_MD_AP);
 
 	mtspr(SPRN_MD_AP, MD_APG_KUAP);
@@ -93,20 +73,14 @@ static inline unsigned long prevent_user_access_return(void)
 	return flags;
 }
 
-static inline void restore_user_access(unsigned long flags)
+static inline void __restore_user_access(unsigned long flags)
 {
-	if (kuap_is_disabled())
-		return;
-
 	mtspr(SPRN_MD_AP, flags);
 }
 
 static inline bool
-bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
+__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
 {
-	if (kuap_is_disabled())
-		return false;
-
 	return !((regs->kuap ^ MD_APG_KUAP) & 0xff000000);
 }
 
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-44x.h b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
index 43ceca128531..2d92a39d8f2e 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-44x.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-44x.h
@@ -113,7 +113,6 @@ typedef struct {
 
 /* patch sites */
 extern s32 patch__tlb_44x_hwater_D, patch__tlb_44x_hwater_I;
-extern s32 patch__tlb_44x_kuep, patch__tlb_47x_kuep;
 
 #endif /* !__ASSEMBLY__ */
 
diff --git a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
index 997cec973406..0e93a4728c9e 100644
--- a/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
+++ b/arch/powerpc/include/asm/nohash/32/mmu-8xx.h
@@ -39,12 +39,10 @@
  * 0 => Kernel => 11 (all accesses performed according as user iaw page definition)
  * 1 => Kernel+Accessed => 01 (all accesses performed according to page definition)
  * 2 => User => 11 (all accesses performed according as user iaw page definition)
- * 3 => User+Accessed => 00 (all accesses performed as supervisor iaw page definition) for INIT
- *                    => 10 (all accesses performed according to swaped page definition) for KUEP
+ * 3 => User+Accessed => 10 (all accesses performed according to swaped page definition) for KUEP
  * 4-15 => Not Used
  */
-#define MI_APG_INIT	0xdc000000
-#define MI_APG_KUEP	0xde000000
+#define MI_APG_INIT	0xde000000
 
 /* The effective page number register.  When read, contains the information
  * about the last instruction TLB miss.  When MI_RPN is written, bits in
diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index b67742e2a9b2..d959c2a73fbf 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -64,6 +64,7 @@ extern int icache_44x_need_flush;
 #ifndef __ASSEMBLY__
 
 int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot);
+void unmap_kernel_page(unsigned long va);
 
 #endif /* !__ASSEMBLY__ */
 
diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
index 9d2905a47410..2816d158280a 100644
--- a/arch/powerpc/include/asm/nohash/64/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
@@ -308,11 +308,18 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
 #define __swp_entry_to_pte(x)		__pte((x).val)
 
 int map_kernel_page(unsigned long ea, unsigned long pa, pgprot_t prot);
+void unmap_kernel_page(unsigned long va);
 extern int __meminit vmemmap_create_mapping(unsigned long start,
 					    unsigned long page_size,
 					    unsigned long phys);
 extern void vmemmap_remove_mapping(unsigned long start,
 				   unsigned long page_size);
+void __patch_exception(int exc, unsigned long addr);
+#define patch_exception(exc, name) do { \
+	extern unsigned int name; \
+	__patch_exception((exc), (unsigned long)&name); \
+} while (0)
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_POWERPC_NOHASH_64_PGTABLE_H */
diff --git a/arch/powerpc/include/asm/nohash/kup-booke.h b/arch/powerpc/include/asm/nohash/kup-booke.h
new file mode 100644
index 000000000000..49bb41ed0816
--- /dev/null
+++ b/arch/powerpc/include/asm/nohash/kup-booke.h
@@ -0,0 +1,110 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_KUP_BOOKE_H_
+#define _ASM_POWERPC_KUP_BOOKE_H_
+
+#include <asm/bug.h>
+
+#ifdef CONFIG_PPC_KUAP
+
+#ifdef __ASSEMBLY__
+
+.macro kuap_check_amr	gpr1, gpr2
+.endm
+
+#else
+
+#include <linux/jump_label.h>
+#include <linux/sched.h>
+
+#include <asm/reg.h>
+
+extern struct static_key_false disable_kuap_key;
+
+static __always_inline bool kuap_is_disabled(void)
+{
+	return static_branch_unlikely(&disable_kuap_key);
+}
+
+static inline void __kuap_lock(void)
+{
+	mtspr(SPRN_PID, 0);
+	isync();
+}
+
+static inline void __kuap_save_and_lock(struct pt_regs *regs)
+{
+	regs->kuap = mfspr(SPRN_PID);
+	mtspr(SPRN_PID, 0);
+	isync();
+}
+
+static inline void kuap_user_restore(struct pt_regs *regs)
+{
+	if (kuap_is_disabled())
+		return;
+
+	mtspr(SPRN_PID, current->thread.pid);
+
+	/* Context synchronisation is performed by rfi */
+}
+
+static inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap)
+{
+	if (regs->kuap)
+		mtspr(SPRN_PID, current->thread.pid);
+
+	/* Context synchronisation is performed by rfi */
+}
+
+static inline unsigned long __kuap_get_and_assert_locked(void)
+{
+	unsigned long kuap = mfspr(SPRN_PID);
+
+	if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG))
+		WARN_ON_ONCE(kuap);
+
+	return kuap;
+}
+
+static inline void __allow_user_access(void __user *to, const void __user *from,
+				       unsigned long size, unsigned long dir)
+{
+	mtspr(SPRN_PID, current->thread.pid);
+	isync();
+}
+
+static inline void __prevent_user_access(unsigned long dir)
+{
+	mtspr(SPRN_PID, 0);
+	isync();
+}
+
+static inline unsigned long __prevent_user_access_return(void)
+{
+	unsigned long flags = mfspr(SPRN_PID);
+
+	mtspr(SPRN_PID, 0);
+	isync();
+
+	return flags;
+}
+
+static inline void __restore_user_access(unsigned long flags)
+{
+	if (flags) {
+		mtspr(SPRN_PID, current->thread.pid);
+		isync();
+	}
+}
+
+static inline bool
+__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
+{
+	return !regs->kuap;
+}
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* CONFIG_PPC_KUAP */
+
+#endif /* _ASM_POWERPC_KUP_BOOKE_H_ */