summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJakub Jelinek <jakub@redhat.com>2006-09-26 14:00:56 -0700
committerTony Luck <tony.luck@intel.com>2006-09-26 14:00:56 -0700
commita192dc16000241dc02990a36b6830839b73c44de (patch)
tree31c228936a92bab32d950aadce2316cc7abdc39b
parentfd1dfc6f0165e2ad426665e517103672d6832f90 (diff)
downloadop-kernel-dev-a192dc16000241dc02990a36b6830839b73c44de.zip
op-kernel-dev-a192dc16000241dc02990a36b6830839b73c44de.tar.gz
[IA64] Implement futex primitives
Implement futex_atomic_op_inuser() and futex_atomic_cmpxchg_inatomic() on IA64 in order to fully support all futex functionality. Signed-off-by: Jakub Jelinek <jakub@redhat.com> Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
-rw-r--r--include/asm-ia64/futex.h122
1 files changed, 120 insertions, 2 deletions
diff --git a/include/asm-ia64/futex.h b/include/asm-ia64/futex.h
index 6a332a9..07d77f3 100644
--- a/include/asm-ia64/futex.h
+++ b/include/asm-ia64/futex.h
@@ -1,6 +1,124 @@
#ifndef _ASM_FUTEX_H
#define _ASM_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_atomic_op1(insn, ret, oldval, uaddr, oparg) \
+do { \
+ register unsigned long r8 __asm ("r8") = 0; \
+ __asm__ __volatile__( \
+ " mf;; \n" \
+ "[1:] " insn ";; \n" \
+ " .xdata4 \"__ex_table\", 1b-., 2f-. \n" \
+ "[2:]" \
+ : "+r" (r8), "=r" (oldval) \
+ : "r" (uaddr), "r" (oparg) \
+ : "memory"); \
+ ret = r8; \
+} while (0)
+
+#define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
+do { \
+ register unsigned long r8 __asm ("r8") = 0; \
+ int val, newval; \
+ do { \
+ __asm__ __volatile__( \
+ " mf;; \n" \
+ "[1:] ld4 %3=[%4];; \n" \
+ " mov %2=%3 \n" \
+ insn ";; \n" \
+ " mov ar.ccv=%2;; \n" \
+ "[2:] cmpxchg4.acq %1=[%4],%3,ar.ccv;; \n" \
+ " .xdata4 \"__ex_table\", 1b-., 3f-.\n" \
+ " .xdata4 \"__ex_table\", 2b-., 3f-.\n" \
+ "[3:]" \
+ : "+r" (r8), "=r" (val), "=&r" (oldval), \
+ "=&r" (newval) \
+ : "r" (uaddr), "r" (oparg) \
+ : "memory"); \
+ if (unlikely (r8)) \
+ break; \
+ } while (unlikely (val != oldval)); \
+ ret = r8; \
+} while (0)
+
+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;
+ if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+ oparg = 1 << oparg;
+
+ if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
+ return -EFAULT;
+
+ inc_preempt_count();
+
+ switch (op) {
+ case FUTEX_OP_SET:
+ __futex_atomic_op1("xchg4 %1=[%2],%3", ret, oldval, uaddr,
+ oparg);
+ break;
+ case FUTEX_OP_ADD:
+ __futex_atomic_op2("add %3=%3,%5", ret, oldval, uaddr, oparg);
+ break;
+ case FUTEX_OP_OR:
+ __futex_atomic_op2("or %3=%3,%5", ret, oldval, uaddr, oparg);
+ break;
+ case FUTEX_OP_ANDN:
+ __futex_atomic_op2("and %3=%3,%5", ret, oldval, uaddr,
+ ~oparg);
+ break;
+ case FUTEX_OP_XOR:
+ __futex_atomic_op2("xor %3=%3,%5", 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;
+}
+
+static inline int
+futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
+{
+ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+ return -EFAULT;
+
+ {
+ register unsigned long r8 __asm ("r8");
+ __asm__ __volatile__(
+ " mf;; \n"
+ " mov ar.ccv=%3;; \n"
+ "[1:] cmpxchg4.acq %0=[%1],%2,ar.ccv \n"
+ " .xdata4 \"__ex_table\", 1b-., 2f-. \n"
+ "[2:]"
+ : "=r" (r8)
+ : "r" (uaddr), "r" (newval),
+ "rO" ((long) (unsigned) oldval)
+ : "memory");
+ return r8;
+ }
+}
+
+#endif /* _ASM_FUTEX_H */
OpenPOWER on IntegriCloud