[PATCH v2 07/15] riscv: misaligned: factorize trap handling

[Clément Léger]

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 <cle...@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,
-- 
2.47.2