1 files changed, 60 insertions, 29 deletions

diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 0cda653ae007..3c40ebd50f92 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -358,7 +358,8 @@ static int __init setup_hugepagesz(char *string)
         }
 
         if ((hv_pgsz_mask & cpu_pgsz_mask) == 0U) {
-                pr_warn("hugepagesz=%llu not supported by MMU.\n",
+                hugetlb_bad_size();
+                pr_err("hugepagesz=%llu not supported by MMU.\n",
                         hugepage_size);
                 goto out;
         }
@@ -706,10 +707,58 @@ EXPORT_SYMBOL(__flush_dcache_range);
 
 /* get_new_mmu_context() uses "cache + 1".  */
 DEFINE_SPINLOCK(ctx_alloc_lock);
-unsigned long tlb_context_cache = CTX_FIRST_VERSION - 1;
+unsigned long tlb_context_cache = CTX_FIRST_VERSION;
 #define MAX_CTX_NR      (1UL << CTX_NR_BITS)
 #define CTX_BMAP_SLOTS  BITS_TO_LONGS(MAX_CTX_NR)
 DECLARE_BITMAP(mmu_context_bmap, MAX_CTX_NR);
+DEFINE_PER_CPU(struct mm_struct *, per_cpu_secondary_mm) = {0};
+
+static void mmu_context_wrap(void)
+{
+        unsigned long old_ver = tlb_context_cache & CTX_VERSION_MASK;
+        unsigned long new_ver, new_ctx, old_ctx;
+        struct mm_struct *mm;
+        int cpu;
+
+        bitmap_zero(mmu_context_bmap, 1 << CTX_NR_BITS);
+
+        /* Reserve kernel context */
+        set_bit(0, mmu_context_bmap);
+
+        new_ver = (tlb_context_cache & CTX_VERSION_MASK) + CTX_FIRST_VERSION;
+        if (unlikely(new_ver == 0))
+                new_ver = CTX_FIRST_VERSION;
+        tlb_context_cache = new_ver;
+
+        /*
+         * Make sure that any new mm that are added into per_cpu_secondary_mm,
+         * are going to go through get_new_mmu_context() path.
+         */
+        mb();
+
+        /*
+         * Updated versions to current on those CPUs that had valid secondary
+         * contexts
+         */
+        for_each_online_cpu(cpu) {
+                /*
+                 * If a new mm is stored after we took this mm from the array,
+                 * it will go into get_new_mmu_context() path, because we
+                 * already bumped the version in tlb_context_cache.
+                 */
+                mm = per_cpu(per_cpu_secondary_mm, cpu);
+
+                if (unlikely(!mm || mm == &init_mm))
+                        continue;
+
+                old_ctx = mm->context.sparc64_ctx_val;
+                if (likely((old_ctx & CTX_VERSION_MASK) == old_ver)) {
+                        new_ctx = (old_ctx & ~CTX_VERSION_MASK) | new_ver;
+                        set_bit(new_ctx & CTX_NR_MASK, mmu_context_bmap);
+                        mm->context.sparc64_ctx_val = new_ctx;
+                }
+        }
+}
 
 /* Caller does TLB context flushing on local CPU if necessary.
  * The caller also ensures that CTX_VALID(mm->context) is false.
@@ -725,48 +774,30 @@ void get_new_mmu_context(struct mm_struct *mm)
 {
         unsigned long ctx, new_ctx;
         unsigned long orig_pgsz_bits;
-        int new_version;
 
         spin_lock(&ctx_alloc_lock);
+retry:
+        /* wrap might have happened, test again if our context became valid */
+        if (unlikely(CTX_VALID(mm->context)))
+                goto out;
         orig_pgsz_bits = (mm->context.sparc64_ctx_val & CTX_PGSZ_MASK);
         ctx = (tlb_context_cache + 1) & CTX_NR_MASK;
         new_ctx = find_next_zero_bit(mmu_context_bmap, 1 << CTX_NR_BITS, ctx);
-        new_version = 0;
         if (new_ctx >= (1 << CTX_NR_BITS)) {
                 new_ctx = find_next_zero_bit(mmu_context_bmap, ctx, 1);
                 if (new_ctx >= ctx) {
-                        int i;
-                        new_ctx = (tlb_context_cache & CTX_VERSION_MASK) +
-                                CTX_FIRST_VERSION;
-                        if (new_ctx == 1)
-                                new_ctx = CTX_FIRST_VERSION;
-
-                        /* Don't call memset, for 16 entries that's just
-                         * plain silly...
-                         */
-                        mmu_context_bmap[0] = 3;
-                        mmu_context_bmap[1] = 0;
-                        mmu_context_bmap[2] = 0;
-                        mmu_context_bmap[3] = 0;
-                        for (i = 4; i < CTX_BMAP_SLOTS; i += 4) {
-                                mmu_context_bmap[i + 0] = 0;
-                                mmu_context_bmap[i + 1] = 0;
-                                mmu_context_bmap[i + 2] = 0;
-                                mmu_context_bmap[i + 3] = 0;
-                        }
-                        new_version = 1;
-                        goto out;
+                        mmu_context_wrap();
+                        goto retry;
                 }
         }
+        if (mm->context.sparc64_ctx_val)
+                cpumask_clear(mm_cpumask(mm));
         mmu_context_bmap[new_ctx>>6] |= (1UL << (new_ctx & 63));
         new_ctx |= (tlb_context_cache & CTX_VERSION_MASK);
-out:
         tlb_context_cache = new_ctx;
         mm->context.sparc64_ctx_val = new_ctx | orig_pgsz_bits;
+out:
         spin_unlock(&ctx_alloc_lock);
-
-        if (unlikely(new_version))
-                smp_new_mmu_context_version();
 }
 
 static int numa_enabled = 1;