[SPARC64]: Implement futex_atomic_op_inuser().
authorDavid S. Miller <davem@davemloft.net>
Sat, 25 Feb 2006 20:15:31 +0000 (12:15 -0800)
committerDavid S. Miller <davem@sunset.davemloft.net>
Mon, 27 Feb 2006 03:35:58 +0000 (19:35 -0800)
Signed-off-by: David S. Miller <davem@davemloft.net>
include/asm-sparc64/futex.h

index 6a332a9f099c2eafbf78ee5f79056a349d41a775..0caf60147e9746ed58627625066bff7cc3297aa9 100644 (file)
@@ -1,6 +1,86 @@
-#ifndef _ASM_FUTEX_H
-#define _ASM_FUTEX_H
+#ifndef _SPARC64_FUTEX_H
+#define _SPARC64_FUTEX_H
 
-#include <asm-generic/futex.h>
+#include <linux/futex.h>
+#include <asm/errno.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
 
-#endif
+#define __futex_cas_op(insn, ret, oldval, uaddr, oparg)        \
+       __asm__ __volatile__(                           \
+       "\n1:   lduwa   [%3] %%asi, %2\n"               \
+       "       " insn "\n"                             \
+       "2:     casa    [%3] %%asi, %2, %1\n"           \
+       "       cmp     %2, %1\n"                       \
+       "       bne,pn  %%icc, 1b\n"                    \
+       "        mov    0, %0\n"                        \
+       "3:\n"                                          \
+       "       .section .fixup,#alloc,#execinstr\n"    \
+       "       .align  4\n"                            \
+       "4:     ba      3b\n"                           \
+       "        mov    %5, %0\n"                       \
+       "       .previous\n"                            \
+       "       .section __ex_table,#alloc\n"           \
+       "       .align  4\n"                            \
+       "       .word   1b, 4b\n"                       \
+       "       .word   2b, 4b\n"                       \
+       "       .previous\n"                            \
+       : "=&r" (ret), "=&r" (oldval), "=&r" (tem)      \
+       : "r" (uaddr), "r" (oparg), "i" (-EFAULT)       \
+       : "memory")
+
+static inline int futex_atomic_op_inuser(int encoded_op, int __user *uaddr)
+{
+       int op = (encoded_op >> 28) & 7;
+       int cmp = (encoded_op >> 24) & 15;
+       int oparg = (encoded_op << 8) >> 20;
+       int cmparg = (encoded_op << 20) >> 20;
+       int oldval = 0, ret, tem;
+
+       if (unlikely(!access_ok(VERIFY_WRITE, uaddr, sizeof(int))))
+               return -EFAULT;
+       if (unlikely((((unsigned long) uaddr) & 0x3UL)))
+               return -EINVAL;
+
+       if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+               oparg = 1 << oparg;
+
+       inc_preempt_count();
+
+       switch (op) {
+       case FUTEX_OP_SET:
+               __futex_cas_op("mov\t%4, %1", ret, oldval, uaddr, oparg);
+               break;
+       case FUTEX_OP_ADD:
+               __futex_cas_op("add\t%2, %4, %1", ret, oldval, uaddr, oparg);
+               break;
+       case FUTEX_OP_OR:
+               __futex_cas_op("or\t%2, %4, %1", ret, oldval, uaddr, oparg);
+               break;
+       case FUTEX_OP_ANDN:
+               __futex_cas_op("and\t%2, %4, %1", ret, oldval, uaddr, oparg);
+               break;
+       case FUTEX_OP_XOR:
+               __futex_cas_op("xor\t%2, %4, %1", ret, oldval, uaddr, oparg);
+               break;
+       default:
+               ret = -ENOSYS;
+       }
+
+       dec_preempt_count();
+
+       if (!ret) {
+               switch (cmp) {
+               case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
+               case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
+               case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
+               case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
+               case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
+               case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
+               default: ret = -ENOSYS;
+               }
+       }
+       return ret;
+}
+
+#endif /* !(_SPARC64_FUTEX_H) */