s390/uaccess: rework uaccess code - fix locking issues

[linux.git] / arch / s390 / include / asm / mmu_context.h

diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index 71a258839039cb1536955ce7b51551698d9a35a0..71be346d0e3c8074d7be6542815610567ff66606 100644 (file)
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h
@@ -30,27 +30,33 @@ static inline int init_new_context(struct task_struct *tsk,
 
 #define destroy_context(mm)             do { } while (0)
 
-#ifndef CONFIG_64BIT
-#define LCTL_OPCODE "lctl"
-#else
-#define LCTL_OPCODE "lctlg"
-#endif
-
-static inline void update_user_asce(struct mm_struct *mm)
+static inline void update_user_asce(struct mm_struct *mm, int load_primary)
 {
        pgd_t *pgd = mm->pgd;
 
        S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd);
-       /* Load primary space page table origin. */
-       asm volatile(LCTL_OPCODE" 1,1,%0\n" : : "m" (S390_lowcore.user_asce));
+       if (load_primary)
+               __ctl_load(S390_lowcore.user_asce, 1, 1);
        set_fs(current->thread.mm_segment);
 }
 
-static inline void clear_user_asce(struct mm_struct *mm)
+static inline void clear_user_asce(struct mm_struct *mm, int load_primary)
 {
        S390_lowcore.user_asce = S390_lowcore.kernel_asce;
-       asm volatile(LCTL_OPCODE" 1,1,%0\n" : : "m" (S390_lowcore.user_asce));
-       asm volatile(LCTL_OPCODE" 7,7,%0\n" : : "m" (S390_lowcore.user_asce));
+
+       if (load_primary)
+               __ctl_load(S390_lowcore.user_asce, 1, 1);
+       __ctl_load(S390_lowcore.user_asce, 7, 7);
+}
+
+static inline void update_primary_asce(struct task_struct *tsk)
+{
+       unsigned long asce;
+
+       __ctl_store(asce, 1, 1);
+       if (asce != S390_lowcore.kernel_asce)
+               __ctl_load(S390_lowcore.kernel_asce, 1, 1);
+       set_tsk_thread_flag(tsk, TIF_ASCE);
 }
 
 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
@@ -58,6 +64,7 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 {
        int cpu = smp_processor_id();
 
+       update_primary_asce(tsk);
        if (prev == next)
                return;
        if (MACHINE_HAS_TLB_LC)
@@ -66,10 +73,10 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
                /* Delay update_user_asce until all TLB flushes are done. */
                set_tsk_thread_flag(tsk, TIF_TLB_WAIT);
                /* Clear old ASCE by loading the kernel ASCE. */
-               clear_user_asce(next);
+               clear_user_asce(next, 0);
        } else {
                cpumask_set_cpu(cpu, mm_cpumask(next));
-               update_user_asce(next);
+               update_user_asce(next, 0);
                if (next->context.flush_mm)
                        /* Flush pending TLBs */
                        __tlb_flush_mm(next);
@@ -94,7 +101,7 @@ static inline void finish_arch_post_lock_switch(void)
                cpu_relax();
 
        cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm));
-       update_user_asce(mm);
+       update_user_asce(mm, 0);
        if (mm->context.flush_mm)
                __tlb_flush_mm(mm);
        preempt_enable();