Merge branches 'core/debug', 'core/futexes', 'core/locking', 'core/rcu', 'core/signal...

[sfrench/cifs-2.6.git] / arch / s390 / lib / uaccess_pt.c

diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index 7e8efaade2ea1196275dd294ec8b48d2748899d3..d66215b0fde9d8d932cd31a43b3dee2e283b3a4a 100644 (file)
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -302,6 +302,10 @@ static size_t copy_in_user_pt(size_t n, void __user *to,
        pte_t *pte_from, *pte_to;
        int write_user;
 
+       if (segment_eq(get_fs(), KERNEL_DS)) {
+               memcpy((void __force *) to, (void __force *) from, n);
+               return 0;
+       }
        done = 0;
 retry:
        spin_lock(&mm->page_table_lock);
@@ -361,18 +365,10 @@ fault:
                     : "0" (-EFAULT), "d" (oparg), "a" (uaddr),         \
                       "m" (*uaddr) : "cc" );
 
-int futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old)
+static int __futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old)
 {
        int oldval = 0, newval, ret;
 
-       spin_lock(&current->mm->page_table_lock);
-       uaddr = (int __user *) __dat_user_addr((unsigned long) uaddr);
-       if (!uaddr) {
-               spin_unlock(&current->mm->page_table_lock);
-               return -EFAULT;
-       }
-       get_page(virt_to_page(uaddr));
-       spin_unlock(&current->mm->page_table_lock);
        switch (op) {
        case FUTEX_OP_SET:
                __futex_atomic_op("lr %2,%5\n",
@@ -397,15 +393,17 @@ int futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old)
        default:
                ret = -ENOSYS;
        }
-       put_page(virt_to_page(uaddr));
-       *old = oldval;
+       if (ret == 0)
+               *old = oldval;
        return ret;
 }
 
-int futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval)
+int futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old)
 {
        int ret;
 
+       if (segment_eq(get_fs(), KERNEL_DS))
+               return __futex_atomic_op_pt(op, uaddr, oparg, old);
        spin_lock(&current->mm->page_table_lock);
        uaddr = (int __user *) __dat_user_addr((unsigned long) uaddr);
        if (!uaddr) {
@@ -414,13 +412,40 @@ int futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval)
        }
        get_page(virt_to_page(uaddr));
        spin_unlock(&current->mm->page_table_lock);
-       asm volatile("   cs   %1,%4,0(%5)\n"
-                    "0: lr   %0,%1\n"
-                    "1:\n"
-                    EX_TABLE(0b,1b)
+       ret = __futex_atomic_op_pt(op, uaddr, oparg, old);
+       put_page(virt_to_page(uaddr));
+       return ret;
+}
+
+static int __futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval)
+{
+       int ret;
+
+       asm volatile("0: cs   %1,%4,0(%5)\n"
+                    "1: lr   %0,%1\n"
+                    "2:\n"
+                    EX_TABLE(0b,2b) EX_TABLE(1b,2b)
                     : "=d" (ret), "+d" (oldval), "=m" (*uaddr)
                     : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr)
                     : "cc", "memory" );
+       return ret;
+}
+
+int futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval)
+{
+       int ret;
+
+       if (segment_eq(get_fs(), KERNEL_DS))
+               return __futex_atomic_cmpxchg_pt(uaddr, oldval, newval);
+       spin_lock(&current->mm->page_table_lock);
+       uaddr = (int __user *) __dat_user_addr((unsigned long) uaddr);
+       if (!uaddr) {
+               spin_unlock(&current->mm->page_table_lock);
+               return -EFAULT;
+       }
+       get_page(virt_to_page(uaddr));
+       spin_unlock(&current->mm->page_table_lock);
+       ret = __futex_atomic_cmpxchg_pt(uaddr, oldval, newval);
        put_page(virt_to_page(uaddr));
        return ret;
 }