[PATCH 1/5] riscv: misaligned: factorize trap handling

["Clément Léger" <cleger@rivosinc.com>]

misaligned accesses traps are not nmi and should be treated as normal
one using irqentry_enter()/exit(). Since both load/store and user/kernel
should use almost the same path and that we are going to add some code
around that, factorize it.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
---
 arch/riscv/kernel/traps.c | 49 ++++++++++++++++-----------------------
 1 file changed, 20 insertions(+), 29 deletions(-)

diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 8ff8e8b36524..55d9f3450398 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -198,47 +198,38 @@ asmlinkage __visible __trap_section void do_trap_insn_illegal(struct pt_regs *re
 DO_ERROR_INFO(do_trap_load_fault,
 	SIGSEGV, SEGV_ACCERR, "load access fault");
 
-asmlinkage __visible __trap_section void do_trap_load_misaligned(struct pt_regs *regs)
+enum misaligned_access_type {
+	MISALIGNED_STORE,
+	MISALIGNED_LOAD,
+};
+
+static void do_trap_misaligned(struct pt_regs *regs, enum misaligned_access_type type)
 {
-	if (user_mode(regs)) {
-		irqentry_enter_from_user_mode(regs);
+	irqentry_state_t state = irqentry_enter(regs);
 
+	if (type ==  MISALIGNED_LOAD) {
 		if (handle_misaligned_load(regs))
 			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
-			      "Oops - load address misaligned");
-
-		irqentry_exit_to_user_mode(regs);
+				      "Oops - load address misaligned");
 	} else {
-		irqentry_state_t state = irqentry_nmi_enter(regs);
-
-		if (handle_misaligned_load(regs))
+		if (handle_misaligned_store(regs))
 			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
-			      "Oops - load address misaligned");
-
-		irqentry_nmi_exit(regs, state);
+				      "Oops - store (or AMO) address misaligned");
 	}
+
+	irqentry_exit(regs, state);
 }
 
-asmlinkage __visible __trap_section void do_trap_store_misaligned(struct pt_regs *regs)
+asmlinkage __visible __trap_section void do_trap_load_misaligned(struct pt_regs *regs)
 {
-	if (user_mode(regs)) {
-		irqentry_enter_from_user_mode(regs);
-
-		if (handle_misaligned_store(regs))
-			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
-				"Oops - store (or AMO) address misaligned");
-
-		irqentry_exit_to_user_mode(regs);
-	} else {
-		irqentry_state_t state = irqentry_nmi_enter(regs);
-
-		if (handle_misaligned_store(regs))
-			do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->epc,
-				"Oops - store (or AMO) address misaligned");
+	do_trap_misaligned(regs, MISALIGNED_LOAD);
+}
 
-		irqentry_nmi_exit(regs, state);
-	}
+asmlinkage __visible __trap_section void do_trap_store_misaligned(struct pt_regs *regs)
+{
+	do_trap_misaligned(regs, MISALIGNED_STORE);
 }
+
 DO_ERROR_INFO(do_trap_store_fault,
 	SIGSEGV, SEGV_ACCERR, "store (or AMO) access fault");
 DO_ERROR_INFO(do_trap_ecall_s,
-- 
2.49.0