powerpc/64s: Make kuap_check_amr() and kuap_get_and_check_amr() generic

In preparation of porting powerpc32 to C syscall entry/exit,
rename kuap_check_amr() and kuap_get_and_check_amr() as
kuap_assert_locked() and kuap_get_and_assert_locked(), and move in the
generic asm/kup.h the stub for when CONFIG_PPC_KUAP is not selected.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f82614d9b17b83abd739aa18fc08811815d0c2e3.1615552867.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 8bd9050..9700da3 100644 (file)
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -287,7 +287,7 @@ static inline void kuap_kernel_restore(struct pt_regs *regs,
         */
 }
 
-static inline unsigned long kuap_get_and_check_amr(void)
+static inline unsigned long kuap_get_and_assert_locked(void)
 {
        if (mmu_has_feature(MMU_FTR_BOOK3S_KUAP)) {
                unsigned long amr = mfspr(SPRN_AMR);
@@ -298,27 +298,7 @@ static inline unsigned long kuap_get_and_check_amr(void)
        return 0;
 }
 
-#else /* CONFIG_PPC_PKEY */
-
-static inline void kuap_user_restore(struct pt_regs *regs)
-{
-}
-
-static inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long amr)
-{
-}
-
-static inline unsigned long kuap_get_and_check_amr(void)
-{
-       return 0;
-}
-
-#endif /* CONFIG_PPC_PKEY */
-
-
-#ifdef CONFIG_PPC_KUAP
-
-static inline void kuap_check_amr(void)
+static inline void kuap_assert_locked(void)
 {
        if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG) && mmu_has_feature(MMU_FTR_BOOK3S_KUAP))
                WARN_ON_ONCE(mfspr(SPRN_AMR) != AMR_KUAP_BLOCKED);

diff --git a/arch/powerpc/include/asm/kup.h b/arch/powerpc/include/asm/kup.h
index 25671f7..aa5f774 100644 (file)
--- a/arch/powerpc/include/asm/kup.h
+++ b/arch/powerpc/include/asm/kup.h
@@ -74,7 +74,15 @@ bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
        return false;
 }
 
-static inline void kuap_check_amr(void) { }
+static inline void kuap_assert_locked(void) { }
+static inline void kuap_save_and_lock(struct pt_regs *regs) { }
+static inline void kuap_user_restore(struct pt_regs *regs) { }
+static inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) { }
+
+static inline unsigned long kuap_get_and_assert_locked(void)
+{
+       return 0;
+}
 
 /*
  * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush

diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
index 20ace87..a7cb511 100644 (file)
--- a/arch/powerpc/kernel/interrupt.c
+++ b/arch/powerpc/kernel/interrupt.c
@@ -76,7 +76,7 @@ notrace long system_call_exception(long r3, long r4, long r5,
        } else
 #endif
 #ifdef CONFIG_PPC64
-               kuap_check_amr();
+               kuap_assert_locked();
 #endif
 
        booke_restore_dbcr0();
@@ -254,7 +254,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
        CT_WARN_ON(ct_state() == CONTEXT_USER);
 
 #ifdef CONFIG_PPC64
-       kuap_check_amr();
+       kuap_assert_locked();
 #endif
 
        regs->result = r3;
@@ -380,7 +380,7 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned
         * AMR can only have been unlocked if we interrupted the kernel.
         */
 #ifdef CONFIG_PPC64
-       kuap_check_amr();
+       kuap_assert_locked();
 #endif
 
        local_irq_save(flags);
@@ -451,7 +451,7 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
        unsigned long flags;
        unsigned long ret = 0;
 #ifdef CONFIG_PPC64
-       unsigned long amr;
+       unsigned long kuap;
 #endif
 
        if (!IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x) &&
@@ -467,7 +467,7 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsign
                CT_WARN_ON(ct_state() == CONTEXT_USER);
 
 #ifdef CONFIG_PPC64
-       amr = kuap_get_and_check_amr();
+       kuap = kuap_get_and_assert_locked();
 #endif
 
        if (unlikely(current_thread_info()->flags & _TIF_EMULATE_STACK_STORE)) {
@@ -511,7 +511,7 @@ again:
         * value from the check above.
         */
 #ifdef CONFIG_PPC64
-       kuap_kernel_restore(regs, amr);
+       kuap_kernel_restore(regs, kuap);
 #endif
 
        return ret;

diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index d71fd10..5b72abb 100644 (file)
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -282,7 +282,7 @@ static inline void replay_soft_interrupts_irqrestore(void)
         * and re-locking AMR but we shouldn't get here in the first place,
         * hence the warning.
         */
-       kuap_check_amr();
+       kuap_assert_locked();
 
        if (kuap_state != AMR_KUAP_BLOCKED)
                set_kuap(AMR_KUAP_BLOCKED);