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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/microblaze/include/asm/futex.h
Initial import
Diffstat (limited to 'arch/microblaze/include/asm/futex.h')
-rw-r--r--arch/microblaze/include/asm/futex.h129
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/microblaze/include/asm/futex.h b/arch/microblaze/include/asm/futex.h
new file mode 100644
index 000000000..01848f056
--- /dev/null
+++ b/arch/microblaze/include/asm/futex.h
@@ -0,0 +1,129 @@
+#ifndef _ASM_MICROBLAZE_FUTEX_H
+#define _ASM_MICROBLAZE_FUTEX_H
+
+#ifdef __KERNEL__
+
+#include <linux/futex.h>
+#include <linux/uaccess.h>
+#include <asm/errno.h>
+
+#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
+({ \
+ __asm__ __volatile__ ( \
+ "1: lwx %0, %2, r0; " \
+ insn \
+ "2: swx %1, %2, r0; \
+ addic %1, r0, 0; \
+ bnei %1, 1b; \
+ 3: \
+ .section .fixup,\"ax\"; \
+ 4: brid 3b; \
+ addik %1, r0, %3; \
+ .previous; \
+ .section __ex_table,\"a\"; \
+ .word 1b,4b,2b,4b; \
+ .previous;" \
+ : "=&r" (oldval), "=&r" (ret) \
+ : "r" (uaddr), "i" (-EFAULT), "r" (oparg) \
+ ); \
+})
+
+static inline int
+futex_atomic_op_inuser(int encoded_op, u32 __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(u32)))
+ return -EFAULT;
+
+ pagefault_disable();
+
+ switch (op) {
+ case FUTEX_OP_SET:
+ __futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg);
+ break;
+ case FUTEX_OP_ADD:
+ __futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg);
+ break;
+ case FUTEX_OP_OR:
+ __futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg);
+ break;
+ case FUTEX_OP_ANDN:
+ __futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg);
+ break;
+ case FUTEX_OP_XOR:
+ __futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg);
+ break;
+ default:
+ ret = -ENOSYS;
+ }
+
+ pagefault_enable();
+
+ 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(u32 *uval, u32 __user *uaddr,
+ u32 oldval, u32 newval)
+{
+ int ret = 0, cmp;
+ u32 prev;
+
+ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+ return -EFAULT;
+
+ __asm__ __volatile__ ("1: lwx %1, %3, r0; \
+ cmp %2, %1, %4; \
+ bnei %2, 3f; \
+ 2: swx %5, %3, r0; \
+ addic %2, r0, 0; \
+ bnei %2, 1b; \
+ 3: \
+ .section .fixup,\"ax\"; \
+ 4: brid 3b; \
+ addik %0, r0, %6; \
+ .previous; \
+ .section __ex_table,\"a\"; \
+ .word 1b,4b,2b,4b; \
+ .previous;" \
+ : "+r" (ret), "=&r" (prev), "=&r"(cmp) \
+ : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT));
+
+ *uval = prev;
+ return ret;
+}
+
+#endif /* __KERNEL__ */
+
+#endif