sh: Tidy up NEFF-based sign extension for SH-5.

This consolidates all of the NEFF-based sign extension for SH-5.
In the future the other SH code will need to make use of this as well,
so make it generic in preparation for more 32/64 consolidation.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 13 insertions, 25 deletions

diff --git a/arch/sh/kernel/signal_64.c b/arch/sh/kernel/signal_64.c
index 0663a0ee6021..026fd1cfe17d 100644
--- a/arch/sh/kernel/signal_64.c
+++ b/arch/sh/kernel/signal_64.c
@@ -561,13 +561,11 @@ static int setup_frame(int sig, struct k_sigaction *ka,
         /* Set up to return from userspace.  If provided, use a stub
            already in userspace.  */
         if (ka->sa.sa_flags & SA_RESTORER) {
-                DEREF_REG_PR = (unsigned long) ka->sa.sa_restorer | 0x1;
-
                 /*
                  * On SH5 all edited pointers are subject to NEFF
                  */
-                DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ?
-                        (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR;
+                DEREF_REG_PR = neff_sign_extend((unsigned long)
+                        ka->sa.sa_restorer | 0x1);
         } else {
                 /*
                  * Different approach on SH5.
@@ -580,9 +578,8 @@ static int setup_frame(int sig, struct k_sigaction *ka,
                  * . being code, linker turns ShMedia bit on, always
                  *   dereference index -1.
                  */
-                DEREF_REG_PR = (unsigned long) frame->retcode | 0x01;
-                DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ?
-                        (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR;
+                DEREF_REG_PR = neff_sign_extend((unsigned long)
+                        frame->retcode | 0x01);
 
                 if (__copy_to_user(frame->retcode,
                         (void *)((unsigned long)sa_default_restorer & (~1)), 16) != 0)
@@ -596,9 +593,7 @@ static int setup_frame(int sig, struct k_sigaction *ka,
          * Set up registers for signal handler.
          * All edited pointers are subject to NEFF.
          */
-        regs->regs[REG_SP] = (unsigned long) frame;
-        regs->regs[REG_SP] = (regs->regs[REG_SP] & NEFF_SIGN) ?
-                 (regs->regs[REG_SP] | NEFF_MASK) : regs->regs[REG_SP];
+        regs->regs[REG_SP] = neff_sign_extend((unsigned long)frame);
         regs->regs[REG_ARG1] = signal; /* Arg for signal handler */
 
         /* FIXME:
@@ -613,8 +608,7 @@ static int setup_frame(int sig, struct k_sigaction *ka,
         regs->regs[REG_ARG2] = (unsigned long long)(unsigned long)(signed long)&frame->sc;
         regs->regs[REG_ARG3] = (unsigned long long)(unsigned long)(signed long)&frame->sc;
 
-        regs->pc = (unsigned long) ka->sa.sa_handler;
-        regs->pc = (regs->pc & NEFF_SIGN) ? (regs->pc | NEFF_MASK) : regs->pc;
+        regs->pc = neff_sign_extend((unsigned long)ka->sa.sa_handler);
 
         set_fs(USER_DS);
 
@@ -676,13 +670,11 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
         /* Set up to return from userspace.  If provided, use a stub
            already in userspace.  */
         if (ka->sa.sa_flags & SA_RESTORER) {
-                DEREF_REG_PR = (unsigned long) ka->sa.sa_restorer | 0x1;
-
                 /*
                  * On SH5 all edited pointers are subject to NEFF
                  */
-                DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ?
-                        (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR;
+                DEREF_REG_PR = neff_sign_extend((unsigned long)
+                        ka->sa.sa_restorer | 0x1);
         } else {
                 /*
                  * Different approach on SH5.
@@ -695,15 +687,14 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                  * . being code, linker turns ShMedia bit on, always
                  *   dereference index -1.
                  */
-
-                DEREF_REG_PR = (unsigned long) frame->retcode | 0x01;
-                DEREF_REG_PR = (DEREF_REG_PR & NEFF_SIGN) ?
-                        (DEREF_REG_PR | NEFF_MASK) : DEREF_REG_PR;
+                DEREF_REG_PR = neff_sign_extend((unsigned long)
+                        frame->retcode | 0x01);
 
                 if (__copy_to_user(frame->retcode,
                         (void *)((unsigned long)sa_default_rt_restorer & (~1)), 16) != 0)
                         goto give_sigsegv;
 
+                /* Cohere the trampoline with the I-cache. */
                 flush_icache_range(DEREF_REG_PR-1, DEREF_REG_PR-1+15);
         }
 
@@ -711,14 +702,11 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
          * Set up registers for signal handler.
          * All edited pointers are subject to NEFF.
          */
-        regs->regs[REG_SP] = (unsigned long) frame;
-        regs->regs[REG_SP] = (regs->regs[REG_SP] & NEFF_SIGN) ?
-                 (regs->regs[REG_SP] | NEFF_MASK) : regs->regs[REG_SP];
+        regs->regs[REG_SP] = neff_sign_extend((unsigned long)frame);
         regs->regs[REG_ARG1] = signal; /* Arg for signal handler */
         regs->regs[REG_ARG2] = (unsigned long long)(unsigned long)(signed long)&frame->info;
         regs->regs[REG_ARG3] = (unsigned long long)(unsigned long)(signed long)&frame->uc.uc_mcontext;
-        regs->pc = (unsigned long) ka->sa.sa_handler;
-        regs->pc = (regs->pc & NEFF_SIGN) ? (regs->pc | NEFF_MASK) : regs->pc;
+        regs->pc = neff_sign_extend((unsigned long)ka->sa.sa_handler);
 
         set_fs(USER_DS);