sh: use opcode_t and enable unaligned code for sh2a

This patch converts the unaligned access handling code to use opcode_t
instead of u16. While at it, enable unaligned access handling for sh2a.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 25 insertions, 34 deletions

diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index 2e7dd2ebec9a..25b1b8672cf0 100644
--- a/arch/sh/kernel/traps_32.c
+++ b/arch/sh/kernel/traps_32.c
@@ -179,7 +179,7 @@ static inline void sign_extend(unsigned int count, unsigned char *dst)
  *   (if that instruction is in a branch delay slot)
  * - return 0 if emulation okay, -EFAULT on existential error
  */
-static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
+static int handle_unaligned_ins(opcode_t instruction, struct pt_regs *regs)
 {
         int ret, index, count;
         unsigned long *rm, *rn;
@@ -320,11 +320,13 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
  * emulate the instruction in the delay slot
  * - fetches the instruction from PC+2
  */
-static inline int handle_unaligned_delayslot(struct pt_regs *regs)
+static inline int handle_unaligned_delayslot(struct pt_regs *regs,
+                                             opcode_t old_instruction)
 {
-        u16 instruction;
+        opcode_t instruction;
+        void *addr = (void *)(regs->pc + instruction_size(old_instruction));
 
-        if (copy_from_user(&instruction, (u16 *)(regs->pc+2), 2)) {
+        if (copy_from_user(&instruction, addr, sizeof(instruction))) {
                 /* the instruction-fetch faulted */
                 if (user_mode(regs))
                         return -EFAULT;
@@ -334,7 +336,7 @@ static inline int handle_unaligned_delayslot(struct pt_regs *regs)
                     regs, 0);
         }
 
-        return handle_unaligned_ins(instruction,regs);
+        return handle_unaligned_ins(instruction, regs);
 }
 
 /*
@@ -357,10 +359,10 @@ static inline int handle_unaligned_delayslot(struct pt_regs *regs)
  * XXX: SH-2A needs this too, but it needs an overhaul thanks to mixed 32-bit
  * opcodes..
  */
-#ifndef CONFIG_CPU_SH2A
+
 static int handle_unaligned_notify_count = 10;
 
-static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
+static int handle_unaligned_access(opcode_t instruction, struct pt_regs *regs)
 {
         u_int rm;
         int ret, index;
@@ -375,7 +377,7 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
                 printk(KERN_NOTICE "Fixing up unaligned userspace access "
                        "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
                        current->comm, task_pid_nr(current),
-                       (u16 *)regs->pc, instruction);
+                       (void *)regs->pc, instruction);
         }
 
         ret = -EFAULT;
@@ -383,19 +385,19 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
         case 0x0000:
                 if (instruction==0x000B) {
                         /* rts */
-                        ret = handle_unaligned_delayslot(regs);
+                        ret = handle_unaligned_delayslot(regs, instruction);
                         if (ret==0)
                                 regs->pc = regs->pr;
                 }
                 else if ((instruction&0x00FF)==0x0023) {
                         /* braf @Rm */
-                        ret = handle_unaligned_delayslot(regs);
+                        ret = handle_unaligned_delayslot(regs, instruction);
                         if (ret==0)
                                 regs->pc += rm + 4;
                 }
                 else if ((instruction&0x00FF)==0x0003) {
                         /* bsrf @Rm */
-                        ret = handle_unaligned_delayslot(regs);
+                        ret = handle_unaligned_delayslot(regs, instruction);
                         if (ret==0) {
                                 regs->pr = regs->pc + 4;
                                 regs->pc += rm + 4;
@@ -416,13 +418,13 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
         case 0x4000:
                 if ((instruction&0x00FF)==0x002B) {
                         /* jmp @Rm */
-                        ret = handle_unaligned_delayslot(regs);
+                        ret = handle_unaligned_delayslot(regs, instruction);
                         if (ret==0)
                                 regs->pc = rm;
                 }
                 else if ((instruction&0x00FF)==0x000B) {
                         /* jsr @Rm */
-                        ret = handle_unaligned_delayslot(regs);
+                        ret = handle_unaligned_delayslot(regs, instruction);
                         if (ret==0) {
                                 regs->pr = regs->pc + 4;
                                 regs->pc = rm;
@@ -449,7 +451,7 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
                 case 0x0B00: /* bf   lab - no delayslot*/
                         break;
                 case 0x0F00: /* bf/s lab */
-                        ret = handle_unaligned_delayslot(regs);
+                        ret = handle_unaligned_delayslot(regs, instruction);
                         if (ret==0) {
 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
                                 if ((regs->sr & 0x00000001) != 0)
@@ -462,7 +464,7 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
                 case 0x0900: /* bt   lab - no delayslot */
                         break;
                 case 0x0D00: /* bt/s lab */
-                        ret = handle_unaligned_delayslot(regs);
+                        ret = handle_unaligned_delayslot(regs, instruction);
                         if (ret==0) {
 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
                                 if ((regs->sr & 0x00000001) == 0)
@@ -476,13 +478,13 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
                 break;
 
         case 0xA000: /* bra label */
-                ret = handle_unaligned_delayslot(regs);
+                ret = handle_unaligned_delayslot(regs, instruction);
                 if (ret==0)
                         regs->pc += SH_PC_12BIT_OFFSET(instruction);
                 break;
 
         case 0xB000: /* bsr label */
-                ret = handle_unaligned_delayslot(regs);
+                ret = handle_unaligned_delayslot(regs, instruction);
                 if (ret==0) {
                         regs->pr = regs->pc + 4;
                         regs->pc += SH_PC_12BIT_OFFSET(instruction);
@@ -493,12 +495,11 @@ static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
 
         /* handle non-delay-slot instruction */
  simple:
-        ret = handle_unaligned_ins(instruction,regs);
+        ret = handle_unaligned_ins(instruction, regs);
         if (ret==0)
                 regs->pc += instruction_size(instruction);
         return ret;
 }
-#endif /* CONFIG_CPU_SH2A */
 
 #ifdef CONFIG_CPU_HAS_SR_RB
 #define lookup_exception_vector(x)      \
@@ -526,10 +527,8 @@ asmlinkage void do_address_error(struct pt_regs *regs,
         unsigned long error_code = 0;
         mm_segment_t oldfs;
         siginfo_t info;
-#ifndef CONFIG_CPU_SH2A
-        u16 instruction;
+        opcode_t instruction;
         int tmp;
-#endif
 
         /* Intentional ifdef */
 #ifdef CONFIG_CPU_HAS_SR_RB
@@ -549,9 +548,9 @@ asmlinkage void do_address_error(struct pt_regs *regs,
                         goto uspace_segv;
                 }
 
-#ifndef CONFIG_CPU_SH2A
                 set_fs(USER_DS);
-                if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) {
+                if (copy_from_user(&instruction, (void *)(regs->pc),
+                                   sizeof(instruction))) {
                         /* Argh. Fault on the instruction itself.
                            This should never happen non-SMP
                         */
@@ -564,8 +563,6 @@ asmlinkage void do_address_error(struct pt_regs *regs,
 
                 if (tmp==0)
                         return; /* sorted */
-#endif
-
 uspace_segv:
                 printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
                        "access (PC %lx PR %lx)\n", current->comm, regs->pc,
@@ -580,9 +577,9 @@ uspace_segv:
                 if (regs->pc & 1)
                         die("unaligned program counter", regs, error_code);
 
-#ifndef CONFIG_CPU_SH2A
                 set_fs(KERNEL_DS);
-                if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) {
+                if (copy_from_user(&instruction, (void *)(regs->pc),
+                                   sizeof(instruction))) {
                         /* Argh. Fault on the instruction itself.
                            This should never happen non-SMP
                         */
@@ -592,12 +589,6 @@ uspace_segv:
 
                 handle_unaligned_access(instruction, regs);
                 set_fs(oldfs);
-#else
-                printk(KERN_NOTICE "Killing process \"%s\" due to unaligned "
-                       "access\n", current->comm);
-
-                force_sig(SIGSEGV, current);
-#endif
         }
 }