ARC: Make way for pt_regs != user_regs_struct

These have been register compatible so far. However ARCv2 mandates
different pt_regs layout (due to h/w auto save). To keep pt_regs same
for both, we start by removing the assumption - used mainly for block
copies between the 2 structs in signal handling and ptrace

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

2 files changed, 137 insertions, 9 deletions

diff --git a/arch/arc/kernel/ptrace.c b/arch/arc/kernel/ptrace.c
index 13b3ffb27a38..4dd9e3a8c2da 100644
--- a/arch/arc/kernel/ptrace.c
+++ b/arch/arc/kernel/ptrace.c
@@ -47,10 +47,47 @@ static int genregs_get(struct task_struct *target,
                         offsetof(struct user_regs_struct, LOC) + 4);
 
         REG_O_ZERO(pad);
-        REG_O_CHUNK(scratch, callee, ptregs);
+        REG_O_ONE(scratch.bta, &ptregs->bta);
+        REG_O_ONE(scratch.lp_start, &ptregs->lp_start);
+        REG_O_ONE(scratch.lp_end, &ptregs->lp_end);
+        REG_O_ONE(scratch.lp_count, &ptregs->lp_count);
+        REG_O_ONE(scratch.status32, &ptregs->status32);
+        REG_O_ONE(scratch.ret, &ptregs->ret);
+        REG_O_ONE(scratch.blink, &ptregs->blink);
+        REG_O_ONE(scratch.fp, &ptregs->fp);
+        REG_O_ONE(scratch.gp, &ptregs->r26);
+        REG_O_ONE(scratch.r12, &ptregs->r12);
+        REG_O_ONE(scratch.r11, &ptregs->r11);
+        REG_O_ONE(scratch.r10, &ptregs->r10);
+        REG_O_ONE(scratch.r9, &ptregs->r9);
+        REG_O_ONE(scratch.r8, &ptregs->r8);
+        REG_O_ONE(scratch.r7, &ptregs->r7);
+        REG_O_ONE(scratch.r6, &ptregs->r6);
+        REG_O_ONE(scratch.r5, &ptregs->r5);
+        REG_O_ONE(scratch.r4, &ptregs->r4);
+        REG_O_ONE(scratch.r3, &ptregs->r3);
+        REG_O_ONE(scratch.r2, &ptregs->r2);
+        REG_O_ONE(scratch.r1, &ptregs->r1);
+        REG_O_ONE(scratch.r0, &ptregs->r0);
+        REG_O_ONE(scratch.sp, &ptregs->sp);
+
         REG_O_ZERO(pad2);
-        REG_O_CHUNK(callee, efa, cregs);
-        REG_O_CHUNK(efa, stop_pc, &target->thread.fault_address);
+
+        REG_O_ONE(callee.r25, &cregs->r25);
+        REG_O_ONE(callee.r24, &cregs->r24);
+        REG_O_ONE(callee.r23, &cregs->r23);
+        REG_O_ONE(callee.r22, &cregs->r22);
+        REG_O_ONE(callee.r21, &cregs->r21);
+        REG_O_ONE(callee.r20, &cregs->r20);
+        REG_O_ONE(callee.r19, &cregs->r19);
+        REG_O_ONE(callee.r18, &cregs->r18);
+        REG_O_ONE(callee.r17, &cregs->r17);
+        REG_O_ONE(callee.r16, &cregs->r16);
+        REG_O_ONE(callee.r15, &cregs->r15);
+        REG_O_ONE(callee.r14, &cregs->r14);
+        REG_O_ONE(callee.r13, &cregs->r13);
+
+        REG_O_ONE(efa, &target->thread.fault_address);
 
         if (!ret) {
                 if (in_brkpt_trap(ptregs)) {
@@ -97,12 +134,51 @@ static int genregs_set(struct task_struct *target,
                         offsetof(struct user_regs_struct, LOC) + 4);
 
         REG_IGNORE_ONE(pad);
-        /* TBD: disallow updates to STATUS32 etc*/
-        REG_IN_CHUNK(scratch, pad2, ptregs);    /* pt_regs[bta..sp] */
+
+        REG_IN_ONE(scratch.bta, &ptregs->bta);
+        REG_IN_ONE(scratch.lp_start, &ptregs->lp_start);
+        REG_IN_ONE(scratch.lp_end, &ptregs->lp_end);
+        REG_IN_ONE(scratch.lp_count, &ptregs->lp_count);
+
+        REG_IGNORE_ONE(scratch.status32);
+
+        REG_IN_ONE(scratch.ret, &ptregs->ret);
+        REG_IN_ONE(scratch.blink, &ptregs->blink);
+        REG_IN_ONE(scratch.fp, &ptregs->fp);
+        REG_IN_ONE(scratch.gp, &ptregs->r26);
+        REG_IN_ONE(scratch.r12, &ptregs->r12);
+        REG_IN_ONE(scratch.r11, &ptregs->r11);
+        REG_IN_ONE(scratch.r10, &ptregs->r10);
+        REG_IN_ONE(scratch.r9, &ptregs->r9);
+        REG_IN_ONE(scratch.r8, &ptregs->r8);
+        REG_IN_ONE(scratch.r7, &ptregs->r7);
+        REG_IN_ONE(scratch.r6, &ptregs->r6);
+        REG_IN_ONE(scratch.r5, &ptregs->r5);
+        REG_IN_ONE(scratch.r4, &ptregs->r4);
+        REG_IN_ONE(scratch.r3, &ptregs->r3);
+        REG_IN_ONE(scratch.r2, &ptregs->r2);
+        REG_IN_ONE(scratch.r1, &ptregs->r1);
+        REG_IN_ONE(scratch.r0, &ptregs->r0);
+        REG_IN_ONE(scratch.sp, &ptregs->sp);
+
         REG_IGNORE_ONE(pad2);
-        REG_IN_CHUNK(callee, efa, cregs);       /* callee_regs[r25..r13] */
+
+        REG_IN_ONE(callee.r25, &cregs->r25);
+        REG_IN_ONE(callee.r24, &cregs->r24);
+        REG_IN_ONE(callee.r23, &cregs->r23);
+        REG_IN_ONE(callee.r22, &cregs->r22);
+        REG_IN_ONE(callee.r21, &cregs->r21);
+        REG_IN_ONE(callee.r20, &cregs->r20);
+        REG_IN_ONE(callee.r19, &cregs->r19);
+        REG_IN_ONE(callee.r18, &cregs->r18);
+        REG_IN_ONE(callee.r17, &cregs->r17);
+        REG_IN_ONE(callee.r16, &cregs->r16);
+        REG_IN_ONE(callee.r15, &cregs->r15);
+        REG_IN_ONE(callee.r14, &cregs->r14);
+        REG_IN_ONE(callee.r13, &cregs->r13);
+
         REG_IGNORE_ONE(efa);                    /* efa update invalid */
-        REG_IGNORE_ONE(stop_pc);                        /* PC updated via @ret */
+        REG_IGNORE_ONE(stop_pc);                /* PC updated via @ret */
 
         return ret;
 }
diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c
index 2251fb4bbfd7..b15d2fe9c461 100644
--- a/arch/arc/kernel/signal.c
+++ b/arch/arc/kernel/signal.c
@@ -67,7 +67,33 @@ stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs,
                sigset_t *set)
 {
         int err;
-        err = __copy_to_user(&(sf->uc.uc_mcontext.regs.scratch), regs,
+        struct user_regs_struct uregs;
+
+        uregs.scratch.bta       = regs->bta;
+        uregs.scratch.lp_start  = regs->lp_start;
+        uregs.scratch.lp_end    = regs->lp_end;
+        uregs.scratch.lp_count  = regs->lp_count;
+        uregs.scratch.status32  = regs->status32;
+        uregs.scratch.ret       = regs->ret;
+        uregs.scratch.blink     = regs->blink;
+        uregs.scratch.fp        = regs->fp;
+        uregs.scratch.gp        = regs->r26;
+        uregs.scratch.r12       = regs->r12;
+        uregs.scratch.r11       = regs->r11;
+        uregs.scratch.r10       = regs->r10;
+        uregs.scratch.r9        = regs->r9;
+        uregs.scratch.r8        = regs->r8;
+        uregs.scratch.r7        = regs->r7;
+        uregs.scratch.r6        = regs->r6;
+        uregs.scratch.r5        = regs->r5;
+        uregs.scratch.r4        = regs->r4;
+        uregs.scratch.r3        = regs->r3;
+        uregs.scratch.r2        = regs->r2;
+        uregs.scratch.r1        = regs->r1;
+        uregs.scratch.r0        = regs->r0;
+        uregs.scratch.sp        = regs->sp;
+
+        err = __copy_to_user(&(sf->uc.uc_mcontext.regs.scratch), &uregs.scratch,
                              sizeof(sf->uc.uc_mcontext.regs.scratch));
         err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t));
 
@@ -78,14 +104,40 @@ static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
 {
         sigset_t set;
         int err;
+        struct user_regs_struct uregs;
 
         err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
         if (!err)
                 set_current_blocked(&set);
 
-        err |= __copy_from_user(regs, &(sf->uc.uc_mcontext.regs.scratch),
+        err |= __copy_from_user(&uregs.scratch,
+                                &(sf->uc.uc_mcontext.regs.scratch),
                                 sizeof(sf->uc.uc_mcontext.regs.scratch));
 
+        regs->bta       = uregs.scratch.bta;
+        regs->lp_start  = uregs.scratch.lp_start;
+        regs->lp_end    = uregs.scratch.lp_end;
+        regs->lp_count  = uregs.scratch.lp_count;
+        regs->status32  = uregs.scratch.status32;
+        regs->ret       = uregs.scratch.ret;
+        regs->blink     = uregs.scratch.blink;
+        regs->fp        = uregs.scratch.fp;
+        regs->r26       = uregs.scratch.gp;
+        regs->r12       = uregs.scratch.r12;
+        regs->r11       = uregs.scratch.r11;
+        regs->r10       = uregs.scratch.r10;
+        regs->r9        = uregs.scratch.r9;
+        regs->r8        = uregs.scratch.r8;
+        regs->r7        = uregs.scratch.r7;
+        regs->r6        = uregs.scratch.r6;
+        regs->r5        = uregs.scratch.r5;
+        regs->r4        = uregs.scratch.r4;
+        regs->r3        = uregs.scratch.r3;
+        regs->r2        = uregs.scratch.r2;
+        regs->r1        = uregs.scratch.r1;
+        regs->r0        = uregs.scratch.r0;
+        regs->sp        = uregs.scratch.sp;
+
         return err;
 }