From f21a79cab3773bc17aa845b7738c7f200778a260 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Fri, 15 Dec 2017 16:08:16 -0800 Subject: [PATCH] xtensa: clean up exception handling structure Instead of using flat array of longs use normal C structure and generate EXC_TABLE_* constants in the asm-offsets.c Signed-off-by: Max Filippov --- arch/xtensa/include/asm/ptrace.h | 12 ---------- arch/xtensa/include/asm/regs.h | 1 + arch/xtensa/include/asm/traps.h | 23 +++++++++++++++++++ arch/xtensa/kernel/asm-offsets.c | 13 +++++++++++ arch/xtensa/kernel/traps.c | 39 ++++++++++++++++---------------- 5 files changed, 56 insertions(+), 32 deletions(-) diff --git a/arch/xtensa/include/asm/ptrace.h b/arch/xtensa/include/asm/ptrace.h index 05beae3c6376..3a5c5918aea3 100644 --- a/arch/xtensa/include/asm/ptrace.h +++ b/arch/xtensa/include/asm/ptrace.h @@ -39,18 +39,6 @@ * +-----------------------+ -------- */ -/* Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables). */ - -#define EXC_TABLE_KSTK 0x004 /* Kernel Stack */ -#define EXC_TABLE_DOUBLE_SAVE 0x008 /* Double exception save area for a0 */ -#define EXC_TABLE_FIXUP 0x00c /* Fixup handler */ -#define EXC_TABLE_PARAM 0x010 /* For passing a parameter to fixup */ -#define EXC_TABLE_SYSCALL_SAVE 0x014 /* For fast syscall handler */ -#define EXC_TABLE_FAST_USER 0x100 /* Fast user exception handler */ -#define EXC_TABLE_FAST_KERNEL 0x200 /* Fast kernel exception handler */ -#define EXC_TABLE_DEFAULT 0x300 /* Default C-Handler */ -#define EXC_TABLE_SIZE 0x400 - #ifndef __ASSEMBLY__ #include diff --git a/arch/xtensa/include/asm/regs.h b/arch/xtensa/include/asm/regs.h index 881a1134a4b4..477594e5817f 100644 --- a/arch/xtensa/include/asm/regs.h +++ b/arch/xtensa/include/asm/regs.h @@ -76,6 +76,7 @@ #define EXCCAUSE_COPROCESSOR5_DISABLED 37 #define EXCCAUSE_COPROCESSOR6_DISABLED 38 #define EXCCAUSE_COPROCESSOR7_DISABLED 39 +#define EXCCAUSE_N 64 /* PS register fields. */ diff --git a/arch/xtensa/include/asm/traps.h b/arch/xtensa/include/asm/traps.h index 2e69aa4b843f..5bd197097b77 100644 --- a/arch/xtensa/include/asm/traps.h +++ b/arch/xtensa/include/asm/traps.h @@ -12,6 +12,29 @@ #include +/* + * Per-CPU exception handling data structure. + * EXCSAVE1 points to it. + */ +struct exc_table { + /* Kernel Stack */ + void *kstk; + /* Double exception save area for a0 */ + unsigned long double_save; + /* Fixup handler */ + void *fixup; + /* For passing a parameter to fixup */ + void *fixup_param; + /* For fast syscall handler */ + unsigned long syscall_save; + /* Fast user exception handlers */ + void *fast_user_handler[EXCCAUSE_N]; + /* Fast kernel exception handlers */ + void *fast_kernel_handler[EXCCAUSE_N]; + /* Default C-Handlers */ + void *default_handler[EXCCAUSE_N]; +}; + /* * handler must be either of the following: * void (*)(struct pt_regs *regs); diff --git a/arch/xtensa/kernel/asm-offsets.c b/arch/xtensa/kernel/asm-offsets.c index 3b119b372efd..022cf918ec20 100644 --- a/arch/xtensa/kernel/asm-offsets.c +++ b/arch/xtensa/kernel/asm-offsets.c @@ -132,5 +132,18 @@ int main(void) offsetof(struct debug_table, icount_level_save)); #endif + /* struct exc_table */ + DEFINE(EXC_TABLE_KSTK, offsetof(struct exc_table, kstk)); + DEFINE(EXC_TABLE_DOUBLE_SAVE, offsetof(struct exc_table, double_save)); + DEFINE(EXC_TABLE_FIXUP, offsetof(struct exc_table, fixup)); + DEFINE(EXC_TABLE_PARAM, offsetof(struct exc_table, fixup_param)); + DEFINE(EXC_TABLE_SYSCALL_SAVE, + offsetof(struct exc_table, syscall_save)); + DEFINE(EXC_TABLE_FAST_USER, + offsetof(struct exc_table, fast_user_handler)); + DEFINE(EXC_TABLE_FAST_KERNEL, + offsetof(struct exc_table, fast_kernel_handler)); + DEFINE(EXC_TABLE_DEFAULT, offsetof(struct exc_table, default_handler)); + return 0; } diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c index 9a1fef9c1cc6..32c5207f1226 100644 --- a/arch/xtensa/kernel/traps.c +++ b/arch/xtensa/kernel/traps.c @@ -159,8 +159,7 @@ COPROCESSOR(7), * 2. it is a temporary memory buffer for the exception handlers. */ -DEFINE_PER_CPU(unsigned long, exc_table[EXC_TABLE_SIZE/4]); - +DEFINE_PER_CPU(struct exc_table, exc_table); DEFINE_PER_CPU(struct debug_table, debug_table); void die(const char*, struct pt_regs*, long); @@ -368,28 +367,28 @@ do_debug(struct pt_regs *regs) } -static void set_handler(int idx, void *handler) -{ - unsigned int cpu; - - for_each_possible_cpu(cpu) - per_cpu(exc_table, cpu)[idx] = (unsigned long)handler; -} +#define set_handler(type, cause, handler) \ + do { \ + unsigned int cpu; \ + \ + for_each_possible_cpu(cpu) \ + per_cpu(exc_table, cpu).type[cause] = (handler);\ + } while (0) /* Set exception C handler - for temporary use when probing exceptions */ void * __init trap_set_handler(int cause, void *handler) { - void *previous = (void *)per_cpu(exc_table, 0)[ - EXC_TABLE_DEFAULT / 4 + cause]; - set_handler(EXC_TABLE_DEFAULT / 4 + cause, handler); + void *previous = per_cpu(exc_table, 0).default_handler[cause]; + + set_handler(default_handler, cause, handler); return previous; } static void trap_init_excsave(void) { - unsigned long excsave1 = (unsigned long)this_cpu_ptr(exc_table); + unsigned long excsave1 = (unsigned long)this_cpu_ptr(&exc_table); __asm__ __volatile__("wsr %0, excsave1\n" : : "a" (excsave1)); } @@ -421,10 +420,10 @@ void __init trap_init(void) /* Setup default vectors. */ - for(i = 0; i < 64; i++) { - set_handler(EXC_TABLE_FAST_USER/4 + i, user_exception); - set_handler(EXC_TABLE_FAST_KERNEL/4 + i, kernel_exception); - set_handler(EXC_TABLE_DEFAULT/4 + i, do_unhandled); + for (i = 0; i < EXCCAUSE_N; i++) { + set_handler(fast_user_handler, i, user_exception); + set_handler(fast_kernel_handler, i, kernel_exception); + set_handler(default_handler, i, do_unhandled); } /* Setup specific handlers. */ @@ -436,11 +435,11 @@ void __init trap_init(void) void *handler = dispatch_init_table[i].handler; if (fast == 0) - set_handler (EXC_TABLE_DEFAULT/4 + cause, handler); + set_handler(default_handler, cause, handler); if (fast && fast & USER) - set_handler (EXC_TABLE_FAST_USER/4 + cause, handler); + set_handler(fast_user_handler, cause, handler); if (fast && fast & KRNL) - set_handler (EXC_TABLE_FAST_KERNEL/4 + cause, handler); + set_handler(fast_kernel_handler, cause, handler); } /* Initialize EXCSAVE_1 to hold the address of the exception table. */