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authorRich Felker <dalias@libc.org>2016-04-25 21:58:03 +0000
committerRich Felker <dalias@libc.org>2016-06-08 00:35:55 +0000
commit3ce5077d6e6d553649c0a38fc83c043c7b1d5beb (patch)
tree867d0ba8e5925f6524f35d44fd221d8d309ba360
parente335d837ec52698f2435336038721e8d2b736858 (diff)
downloadlinux-sh-3ce5077d6e6d553649c0a38fc83c043c7b1d5beb.tar.gz
sh: add working futex atomic ops on userspace addresses for smp
The version of futex.h in asm-generic should really be adapted to do the same thing so that this hideous code does not have to be duplicated per-arch. Signed-off-by: Rich Felker <dalias@libc.org>
-rw-r--r--arch/sh/include/asm/futex-cas.h34
-rw-r--r--arch/sh/include/asm/futex-irq.h86
-rw-r--r--arch/sh/include/asm/futex-llsc.h41
-rw-r--r--arch/sh/include/asm/futex.h97
4 files changed, 134 insertions, 124 deletions
diff --git a/arch/sh/include/asm/futex-cas.h b/arch/sh/include/asm/futex-cas.h
new file mode 100644
index 000000000000..251c062bf49f
--- /dev/null
+++ b/arch/sh/include/asm/futex-cas.h
@@ -0,0 +1,34 @@
+#ifndef __ASM_SH_FUTEX_CAS_H
+#define __ASM_SH_FUTEX_CAS_H
+
+static inline int atomic_futex_op_cmpxchg_inatomic(u32 *uval,
+ u32 __user *uaddr,
+ u32 oldval, u32 newval)
+{
+ int err = 0;
+ __asm__ __volatile__(
+ "1:\n\t"
+ "cas.l %2, %1, @r0\n"
+ "2:\n"
+#ifdef CONFIG_MMU
+ ".section .fixup,\"ax\"\n"
+ "3:\n\t"
+ "mov.l 4f, %0\n\t"
+ "jmp @%0\n\t"
+ " mov %3, %0\n\t"
+ ".balign 4\n"
+ "4: .long 2b\n\t"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n\t"
+ ".long 1b, 3b\n\t"
+ ".previous"
+#endif
+ :"+r" (err), "+r" (newval)
+ :"r" (oldval), "i" (-EFAULT), "z" (uaddr)
+ :"t", "memory");
+ if (err) return err;
+ *uval = newval;
+ return 0;
+}
+
+#endif /* __ASM_SH_FUTEX_CAS_H */
diff --git a/arch/sh/include/asm/futex-irq.h b/arch/sh/include/asm/futex-irq.h
index 63d33129ea23..ab01dbee0a82 100644
--- a/arch/sh/include/asm/futex-irq.h
+++ b/arch/sh/include/asm/futex-irq.h
@@ -1,92 +1,6 @@
#ifndef __ASM_SH_FUTEX_IRQ_H
#define __ASM_SH_FUTEX_IRQ_H
-
-static inline int atomic_futex_op_xchg_set(int oparg, u32 __user *uaddr,
- int *oldval)
-{
- unsigned long flags;
- int ret;
-
- local_irq_save(flags);
-
- ret = get_user(*oldval, uaddr);
- if (!ret)
- ret = put_user(oparg, uaddr);
-
- local_irq_restore(flags);
-
- return ret;
-}
-
-static inline int atomic_futex_op_xchg_add(int oparg, u32 __user *uaddr,
- int *oldval)
-{
- unsigned long flags;
- int ret;
-
- local_irq_save(flags);
-
- ret = get_user(*oldval, uaddr);
- if (!ret)
- ret = put_user(*oldval + oparg, uaddr);
-
- local_irq_restore(flags);
-
- return ret;
-}
-
-static inline int atomic_futex_op_xchg_or(int oparg, u32 __user *uaddr,
- int *oldval)
-{
- unsigned long flags;
- int ret;
-
- local_irq_save(flags);
-
- ret = get_user(*oldval, uaddr);
- if (!ret)
- ret = put_user(*oldval | oparg, uaddr);
-
- local_irq_restore(flags);
-
- return ret;
-}
-
-static inline int atomic_futex_op_xchg_and(int oparg, u32 __user *uaddr,
- int *oldval)
-{
- unsigned long flags;
- int ret;
-
- local_irq_save(flags);
-
- ret = get_user(*oldval, uaddr);
- if (!ret)
- ret = put_user(*oldval & oparg, uaddr);
-
- local_irq_restore(flags);
-
- return ret;
-}
-
-static inline int atomic_futex_op_xchg_xor(int oparg, u32 __user *uaddr,
- int *oldval)
-{
- unsigned long flags;
- int ret;
-
- local_irq_save(flags);
-
- ret = get_user(*oldval, uaddr);
- if (!ret)
- ret = put_user(*oldval ^ oparg, uaddr);
-
- local_irq_restore(flags);
-
- return ret;
-}
-
static inline int atomic_futex_op_cmpxchg_inatomic(u32 *uval,
u32 __user *uaddr,
u32 oldval, u32 newval)
diff --git a/arch/sh/include/asm/futex-llsc.h b/arch/sh/include/asm/futex-llsc.h
new file mode 100644
index 000000000000..90b0e9e29930
--- /dev/null
+++ b/arch/sh/include/asm/futex-llsc.h
@@ -0,0 +1,41 @@
+#ifndef __ASM_SH_FUTEX_LLSC_H
+#define __ASM_SH_FUTEX_LLSC_H
+
+static inline int atomic_futex_op_cmpxchg_inatomic(u32 *uval,
+ u32 __user *uaddr,
+ u32 oldval, u32 newval)
+{
+ int err = 0;
+ __asm__ __volatile__(
+ "synco\n"
+ "1:\n\t"
+ "movli.l @%2, r0\n\t"
+ "mov r0, %1\n\t"
+ "cmp/eq %1, %4\n\t"
+ "bf 2f\n\t"
+ "mov %5, r0\n\t"
+ "movco.l r0, @%2\n\t"
+ "bf 1b\n"
+ "2:\n\t"
+ "synco"
+#ifdef CONFIG_MMU
+ ".section .fixup,\"ax\"\n"
+ "3:\n\t"
+ "mov.l 4f, %0\n\t"
+ "jmp @%0\n\t"
+ " mov %3, %0\n\t"
+ ".balign 4\n"
+ "4: .long 2b\n\t"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n\t"
+ ".long 1b, 3b\n\t"
+ ".previous"
+#endif
+ :"+r" (err), "=&r" (*uval)
+ :"r" (uaddr), "i" (-EFAULT), "r" (oldval), "r" (newval)
+ :"t", "memory", "r0");
+ if (err) return err;
+ return 0;
+}
+
+#endif /* __ASM_SH_FUTEX_LLSC_H */
diff --git a/arch/sh/include/asm/futex.h b/arch/sh/include/asm/futex.h
index 7be39a646fbd..d0078747d308 100644
--- a/arch/sh/include/asm/futex.h
+++ b/arch/sh/include/asm/futex.h
@@ -7,16 +7,34 @@
#include <linux/uaccess.h>
#include <asm/errno.h>
-/* XXX: UP variants, fix for SH-4A and SMP.. */
+#if !defined(CONFIG_SMP)
#include <asm/futex-irq.h>
+#elif defined(CONFIG_CPU_J2)
+#include <asm/futex-cas.h>
+#elif defined(CONFIG_CPU_SH4A)
+#include <asm/futex-llsc.h>
+#else
+#error SMP not supported on this configuration.
+#endif
+
+static inline int
+futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
+ u32 oldval, u32 newval)
+{
+ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+ return -EFAULT;
+
+ return atomic_futex_op_cmpxchg_inatomic(uval, uaddr, oldval, newval);
+}
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;
+ u32 oparg = (encoded_op << 8) >> 20;
+ u32 cmparg = (encoded_op << 20) >> 20;
+ u32 oldval, newval, prev;
+ int ret;
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
oparg = 1 << oparg;
@@ -26,26 +44,39 @@ static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
pagefault_disable();
- switch (op) {
- case FUTEX_OP_SET:
- ret = atomic_futex_op_xchg_set(oparg, uaddr, &oldval);
- break;
- case FUTEX_OP_ADD:
- ret = atomic_futex_op_xchg_add(oparg, uaddr, &oldval);
- break;
- case FUTEX_OP_OR:
- ret = atomic_futex_op_xchg_or(oparg, uaddr, &oldval);
- break;
- case FUTEX_OP_ANDN:
- ret = atomic_futex_op_xchg_and(~oparg, uaddr, &oldval);
- break;
- case FUTEX_OP_XOR:
- ret = atomic_futex_op_xchg_xor(oparg, uaddr, &oldval);
- break;
- default:
- ret = -ENOSYS;
- break;
- }
+ do {
+ if (op == FUTEX_OP_SET)
+ ret = oldval = 0;
+ else
+ ret = get_user(oldval, uaddr);
+
+ if (ret) break;
+
+ switch (op) {
+ case FUTEX_OP_SET:
+ newval = oparg;
+ break;
+ case FUTEX_OP_ADD:
+ newval = oldval + oparg;
+ break;
+ case FUTEX_OP_OR:
+ newval = oldval | oparg;
+ break;
+ case FUTEX_OP_ANDN:
+ newval = oldval & ~oparg;
+ break;
+ case FUTEX_OP_XOR:
+ newval = oldval ^ oparg;
+ break;
+ default:
+ ret = -ENOSYS;
+ break;
+ }
+
+ if (ret) break;
+
+ ret = futex_atomic_cmpxchg_inatomic(&prev, uaddr, oldval, newval);
+ } while (!ret && prev != oldval);
pagefault_enable();
@@ -53,10 +84,10 @@ static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
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;
+ case FUTEX_OP_CMP_LT: ret = ((int)oldval < (int)cmparg); break;
+ case FUTEX_OP_CMP_GE: ret = ((int)oldval >= (int)cmparg); break;
+ case FUTEX_OP_CMP_LE: ret = ((int)oldval <= (int)cmparg); break;
+ case FUTEX_OP_CMP_GT: ret = ((int)oldval > (int)cmparg); break;
default: ret = -ENOSYS;
}
}
@@ -64,15 +95,5 @@ static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
return ret;
}
-static inline int
-futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
- u32 oldval, u32 newval)
-{
- if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
- return -EFAULT;
-
- return atomic_futex_op_cmpxchg_inatomic(uval, uaddr, oldval, newval);
-}
-
#endif /* __KERNEL__ */
#endif /* __ASM_SH_FUTEX_H */