FRV: Add support for emulation of userspace atomic ops [try #2]

[linux-2.6-omap-h63xx.git] / arch / frv / kernel / traps.c

diff --git a/arch/frv/kernel/traps.c b/arch/frv/kernel/traps.c
index 2e6098c855787de54e82953bb740110be9ed0011..2f7e66877f3bd17c6b078d00f058f9c1959ff081 100644 (file)
--- a/arch/frv/kernel/traps.c
+++ b/arch/frv/kernel/traps.c
@@ -100,6 +100,233 @@ asmlinkage void illegal_instruction(unsigned long esfr1, unsigned long epcr0, un
        force_sig_info(info.si_signo, &info, current);
 } /* end illegal_instruction() */
 
+/*****************************************************************************/
+/*
+ * handle atomic operations with errors
+ * - arguments in gr8, gr9, gr10
+ * - original memory value placed in gr5
+ * - replacement memory value placed in gr9
+ */
+asmlinkage void atomic_operation(unsigned long esfr1, unsigned long epcr0,
+                                unsigned long esr0)
+{
+       static DEFINE_SPINLOCK(atomic_op_lock);
+       unsigned long x, y, z, *p;
+       mm_segment_t oldfs;
+       siginfo_t info;
+       int ret;
+
+       y = 0;
+       z = 0;
+
+       oldfs = get_fs();
+       if (!user_mode(__frame))
+               set_fs(KERNEL_DS);
+
+       switch (__frame->tbr & TBR_TT) {
+               /* TIRA gr0,#120
+                * u32 __atomic_user_cmpxchg32(u32 *ptr, u32 test, u32 new)
+                */
+       case TBR_TT_ATOMIC_CMPXCHG32:
+               p = (unsigned long *) __frame->gr8;
+               x = __frame->gr9;
+               y = __frame->gr10;
+
+               for (;;) {
+                       ret = get_user(z, p);
+                       if (ret < 0)
+                               goto error;
+
+                       if (z != x)
+                               goto done;
+
+                       spin_lock_irq(&atomic_op_lock);
+
+                       if (__get_user(z, p) == 0) {
+                               if (z != x)
+                                       goto done2;
+
+                               if (__put_user(y, p) == 0)
+                                       goto done2;
+                               goto error2;
+                       }
+
+                       spin_unlock_irq(&atomic_op_lock);
+               }
+
+               /* TIRA gr0,#121
+                * u32 __atomic_kernel_xchg32(void *v, u32 new)
+                */
+       case TBR_TT_ATOMIC_XCHG32:
+               p = (unsigned long *) __frame->gr8;
+               y = __frame->gr9;
+
+               for (;;) {
+                       ret = get_user(z, p);
+                       if (ret < 0)
+                               goto error;
+
+                       spin_lock_irq(&atomic_op_lock);
+
+                       if (__get_user(z, p) == 0) {
+                               if (__put_user(y, p) == 0)
+                                       goto done2;
+                               goto error2;
+                       }
+
+                       spin_unlock_irq(&atomic_op_lock);
+               }
+
+               /* TIRA gr0,#122
+                * ulong __atomic_kernel_XOR_return(ulong i, ulong *v)
+                */
+       case TBR_TT_ATOMIC_XOR:
+               p = (unsigned long *) __frame->gr8;
+               x = __frame->gr9;
+
+               for (;;) {
+                       ret = get_user(z, p);
+                       if (ret < 0)
+                               goto error;
+
+                       spin_lock_irq(&atomic_op_lock);
+
+                       if (__get_user(z, p) == 0) {
+                               y = x ^ z;
+                               if (__put_user(y, p) == 0)
+                                       goto done2;
+                               goto error2;
+                       }
+
+                       spin_unlock_irq(&atomic_op_lock);
+               }
+
+               /* TIRA gr0,#123
+                * ulong __atomic_kernel_OR_return(ulong i, ulong *v)
+                */
+       case TBR_TT_ATOMIC_OR:
+               p = (unsigned long *) __frame->gr8;
+               x = __frame->gr9;
+
+               for (;;) {
+                       ret = get_user(z, p);
+                       if (ret < 0)
+                               goto error;
+
+                       spin_lock_irq(&atomic_op_lock);
+
+                       if (__get_user(z, p) == 0) {
+                               y = x ^ z;
+                               if (__put_user(y, p) == 0)
+                                       goto done2;
+                               goto error2;
+                       }
+
+                       spin_unlock_irq(&atomic_op_lock);
+               }
+
+               /* TIRA gr0,#124
+                * ulong __atomic_kernel_AND_return(ulong i, ulong *v)
+                */
+       case TBR_TT_ATOMIC_AND:
+               p = (unsigned long *) __frame->gr8;
+               x = __frame->gr9;
+
+               for (;;) {
+                       ret = get_user(z, p);
+                       if (ret < 0)
+                               goto error;
+
+                       spin_lock_irq(&atomic_op_lock);
+
+                       if (__get_user(z, p) == 0) {
+                               y = x & z;
+                               if (__put_user(y, p) == 0)
+                                       goto done2;
+                               goto error2;
+                       }
+
+                       spin_unlock_irq(&atomic_op_lock);
+               }
+
+               /* TIRA gr0,#125
+                * int __atomic_user_sub_return(atomic_t *v, int i)
+                */
+       case TBR_TT_ATOMIC_SUB:
+               p = (unsigned long *) __frame->gr8;
+               x = __frame->gr9;
+
+               for (;;) {
+                       ret = get_user(z, p);
+                       if (ret < 0)
+                               goto error;
+
+                       spin_lock_irq(&atomic_op_lock);
+
+                       if (__get_user(z, p) == 0) {
+                               y = z - x;
+                               if (__put_user(y, p) == 0)
+                                       goto done2;
+                               goto error2;
+                       }
+
+                       spin_unlock_irq(&atomic_op_lock);
+               }
+
+               /* TIRA gr0,#126
+                * int __atomic_user_add_return(atomic_t *v, int i)
+                */
+       case TBR_TT_ATOMIC_ADD:
+               p = (unsigned long *) __frame->gr8;
+               x = __frame->gr9;
+
+               for (;;) {
+                       ret = get_user(z, p);
+                       if (ret < 0)
+                               goto error;
+
+                       spin_lock_irq(&atomic_op_lock);
+
+                       if (__get_user(z, p) == 0) {
+                               y = z + x;
+                               if (__put_user(y, p) == 0)
+                                       goto done2;
+                               goto error2;
+                       }
+
+                       spin_unlock_irq(&atomic_op_lock);
+               }
+
+       default:
+               BUG();
+       }
+
+done2:
+       spin_unlock_irq(&atomic_op_lock);
+done:
+       if (!user_mode(__frame))
+               set_fs(oldfs);
+       __frame->gr5 = z;
+       __frame->gr9 = y;
+       return;
+
+error2:
+       spin_unlock_irq(&atomic_op_lock);
+error:
+       if (!user_mode(__frame))
+               set_fs(oldfs);
+       __frame->pc -= 4;
+
+       die_if_kernel("-- Atomic Op Error --\n");
+
+       info.si_signo   = SIGSEGV;
+       info.si_code    = SEGV_ACCERR;
+       info.si_errno   = 0;
+       info.si_addr    = (void *) __frame->pc;
+
+       force_sig_info(info.si_signo, &info, current);
+}
+
 /*****************************************************************************/
 /*
  *