Merge branch 'for-linus' of git://github.com/cmetcalf-tilera/linux-tile

[cascardo/linux.git] / arch / s390 / mm / pgtable.c

diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index e4a4cef..301c84d 100644 (file)
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -1,5 +1,5 @@
 /*
- *    Copyright IBM Corp. 2007,2009
+ *    Copyright IBM Corp. 2007,2011
  *    Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
  */
 
@@ -222,6 +222,7 @@ void gmap_free(struct gmap *gmap)
 
        /* Free all segment & region tables. */
        down_read(&gmap->mm->mmap_sem);
+       spin_lock(&gmap->mm->page_table_lock);
        list_for_each_entry_safe(page, next, &gmap->crst_list, lru) {
                table = (unsigned long *) page_to_phys(page);
                if ((*table & _REGION_ENTRY_TYPE_MASK) == 0)
@@ -230,6 +231,7 @@ void gmap_free(struct gmap *gmap)
                                gmap_unlink_segment(gmap, table);
                __free_pages(page, ALLOC_ORDER);
        }
+       spin_unlock(&gmap->mm->page_table_lock);
        up_read(&gmap->mm->mmap_sem);
        list_del(&gmap->list);
        kfree(gmap);
@@ -300,6 +302,7 @@ int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
 
        flush = 0;
        down_read(&gmap->mm->mmap_sem);
+       spin_lock(&gmap->mm->page_table_lock);
        for (off = 0; off < len; off += PMD_SIZE) {
                /* Walk the guest addr space page table */
                table = gmap->table + (((to + off) >> 53) & 0x7ff);
@@ -321,6 +324,7 @@ int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
                *table = _SEGMENT_ENTRY_INV;
        }
 out:
+       spin_unlock(&gmap->mm->page_table_lock);
        up_read(&gmap->mm->mmap_sem);
        if (flush)
                gmap_flush_tlb(gmap);
@@ -351,6 +355,7 @@ int gmap_map_segment(struct gmap *gmap, unsigned long from,
 
        flush = 0;
        down_read(&gmap->mm->mmap_sem);
+       spin_lock(&gmap->mm->page_table_lock);
        for (off = 0; off < len; off += PMD_SIZE) {
                /* Walk the gmap address space page table */
                table = gmap->table + (((to + off) >> 53) & 0x7ff);
@@ -374,19 +379,24 @@ int gmap_map_segment(struct gmap *gmap, unsigned long from,
                flush |= gmap_unlink_segment(gmap, table);
                *table = _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO | (from + off);
        }
+       spin_unlock(&gmap->mm->page_table_lock);
        up_read(&gmap->mm->mmap_sem);
        if (flush)
                gmap_flush_tlb(gmap);
        return 0;
 
 out_unmap:
+       spin_unlock(&gmap->mm->page_table_lock);
        up_read(&gmap->mm->mmap_sem);
        gmap_unmap_segment(gmap, to, len);
        return -ENOMEM;
 }
 EXPORT_SYMBOL_GPL(gmap_map_segment);
 
-unsigned long gmap_fault(unsigned long address, struct gmap *gmap)
+/*
+ * this function is assumed to be called with mmap_sem held
+ */
+unsigned long __gmap_fault(unsigned long address, struct gmap *gmap)
 {
        unsigned long *table, vmaddr, segment;
        struct mm_struct *mm;
@@ -446,16 +456,75 @@ unsigned long gmap_fault(unsigned long address, struct gmap *gmap)
                page = pmd_page(*pmd);
                mp = (struct gmap_pgtable *) page->index;
                rmap->entry = table;
+               spin_lock(&mm->page_table_lock);
                list_add(&rmap->list, &mp->mapper);
+               spin_unlock(&mm->page_table_lock);
                /* Set gmap segment table entry to page table. */
                *table = pmd_val(*pmd) & PAGE_MASK;
                return vmaddr | (address & ~PMD_MASK);
        }
        return -EFAULT;
+}
 
+unsigned long gmap_fault(unsigned long address, struct gmap *gmap)
+{
+       unsigned long rc;
+
+       down_read(&gmap->mm->mmap_sem);
+       rc = __gmap_fault(address, gmap);
+       up_read(&gmap->mm->mmap_sem);
+
+       return rc;
 }
 EXPORT_SYMBOL_GPL(gmap_fault);
 
+void gmap_discard(unsigned long from, unsigned long to, struct gmap *gmap)
+{
+
+       unsigned long *table, address, size;
+       struct vm_area_struct *vma;
+       struct gmap_pgtable *mp;
+       struct page *page;
+
+       down_read(&gmap->mm->mmap_sem);
+       address = from;
+       while (address < to) {
+               /* Walk the gmap address space page table */
+               table = gmap->table + ((address >> 53) & 0x7ff);
+               if (unlikely(*table & _REGION_ENTRY_INV)) {
+                       address = (address + PMD_SIZE) & PMD_MASK;
+                       continue;
+               }
+               table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+               table = table + ((address >> 42) & 0x7ff);
+               if (unlikely(*table & _REGION_ENTRY_INV)) {
+                       address = (address + PMD_SIZE) & PMD_MASK;
+                       continue;
+               }
+               table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+               table = table + ((address >> 31) & 0x7ff);
+               if (unlikely(*table & _REGION_ENTRY_INV)) {
+                       address = (address + PMD_SIZE) & PMD_MASK;
+                       continue;
+               }
+               table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+               table = table + ((address >> 20) & 0x7ff);
+               if (unlikely(*table & _SEGMENT_ENTRY_INV)) {
+                       address = (address + PMD_SIZE) & PMD_MASK;
+                       continue;
+               }
+               page = pfn_to_page(*table >> PAGE_SHIFT);
+               mp = (struct gmap_pgtable *) page->index;
+               vma = find_vma(gmap->mm, mp->vmaddr);
+               size = min(to - address, PMD_SIZE - (address & ~PMD_MASK));
+               zap_page_range(vma, mp->vmaddr | (address & ~PMD_MASK),
+                              size, NULL);
+               address = (address + PMD_SIZE) & PMD_MASK;
+       }
+       up_read(&gmap->mm->mmap_sem);
+}
+EXPORT_SYMBOL_GPL(gmap_discard);
+
 void gmap_unmap_notifier(struct mm_struct *mm, unsigned long *table)
 {
        struct gmap_rmap *rmap, *next;