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-rw-r--r--arch/s390/include/asm/pgtable.h2
-rw-r--r--arch/s390/mm/pgtable.c107
2 files changed, 87 insertions, 22 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 4a5443118cfb..fda82d6c7c83 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -760,6 +760,8 @@ void gmap_disable(struct gmap *gmap);
int gmap_map_segment(struct gmap *gmap, unsigned long from,
unsigned long to, unsigned long length);
int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len);
+unsigned long __gmap_translate(unsigned long address, struct gmap *);
+unsigned long gmap_translate(unsigned long address, struct gmap *);
unsigned long __gmap_fault(unsigned long address, struct gmap *);
unsigned long gmap_fault(unsigned long address, struct gmap *);
void gmap_discard(unsigned long from, unsigned long to, struct gmap *);
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index ae44d2a34313..2accf7113d13 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -379,45 +379,108 @@ out_unmap:
}
EXPORT_SYMBOL_GPL(gmap_map_segment);
+static unsigned long *gmap_table_walk(unsigned long address, struct gmap *gmap)
+{
+ unsigned long *table;
+
+ table = gmap->table + ((address >> 53) & 0x7ff);
+ if (unlikely(*table & _REGION_ENTRY_INV))
+ return ERR_PTR(-EFAULT);
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ table = table + ((address >> 42) & 0x7ff);
+ if (unlikely(*table & _REGION_ENTRY_INV))
+ return ERR_PTR(-EFAULT);
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ table = table + ((address >> 31) & 0x7ff);
+ if (unlikely(*table & _REGION_ENTRY_INV))
+ return ERR_PTR(-EFAULT);
+ table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
+ table = table + ((address >> 20) & 0x7ff);
+ return table;
+}
+
+/**
+ * __gmap_translate - translate a guest address to a user space address
+ * @address: guest address
+ * @gmap: pointer to guest mapping meta data structure
+ *
+ * Returns user space address which corresponds to the guest address or
+ * -EFAULT if no such mapping exists.
+ * This function does not establish potentially missing page table entries.
+ * The mmap_sem of the mm that belongs to the address space must be held
+ * when this function gets called.
+ */
+unsigned long __gmap_translate(unsigned long address, struct gmap *gmap)
+{
+ unsigned long *segment_ptr, vmaddr, segment;
+ struct gmap_pgtable *mp;
+ struct page *page;
+
+ current->thread.gmap_addr = address;
+ segment_ptr = gmap_table_walk(address, gmap);
+ if (IS_ERR(segment_ptr))
+ return PTR_ERR(segment_ptr);
+ /* Convert the gmap address to an mm address. */
+ segment = *segment_ptr;
+ if (!(segment & _SEGMENT_ENTRY_INV)) {
+ page = pfn_to_page(segment >> PAGE_SHIFT);
+ mp = (struct gmap_pgtable *) page->index;
+ return mp->vmaddr | (address & ~PMD_MASK);
+ } else if (segment & _SEGMENT_ENTRY_RO) {
+ vmaddr = segment & _SEGMENT_ENTRY_ORIGIN;
+ return vmaddr | (address & ~PMD_MASK);
+ }
+ return -EFAULT;
+}
+EXPORT_SYMBOL_GPL(__gmap_translate);
+
+/**
+ * gmap_translate - translate a guest address to a user space address
+ * @address: guest address
+ * @gmap: pointer to guest mapping meta data structure
+ *
+ * Returns user space address which corresponds to the guest address or
+ * -EFAULT if no such mapping exists.
+ * This function does not establish potentially missing page table entries.
+ */
+unsigned long gmap_translate(unsigned long address, struct gmap *gmap)
+{
+ unsigned long rc;
+
+ down_read(&gmap->mm->mmap_sem);
+ rc = __gmap_translate(address, gmap);
+ up_read(&gmap->mm->mmap_sem);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(gmap_translate);
+
/*
* 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;
+ unsigned long *segment_ptr, vmaddr, segment;
+ struct vm_area_struct *vma;
struct gmap_pgtable *mp;
struct gmap_rmap *rmap;
- struct vm_area_struct *vma;
+ struct mm_struct *mm;
struct page *page;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
current->thread.gmap_addr = address;
- mm = gmap->mm;
- /* Walk the gmap address space page table */
- table = gmap->table + ((address >> 53) & 0x7ff);
- if (unlikely(*table & _REGION_ENTRY_INV))
- return -EFAULT;
- table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
- table = table + ((address >> 42) & 0x7ff);
- if (unlikely(*table & _REGION_ENTRY_INV))
+ segment_ptr = gmap_table_walk(address, gmap);
+ if (IS_ERR(segment_ptr))
return -EFAULT;
- table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
- table = table + ((address >> 31) & 0x7ff);
- if (unlikely(*table & _REGION_ENTRY_INV))
- return -EFAULT;
- table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
- table = table + ((address >> 20) & 0x7ff);
-
/* Convert the gmap address to an mm address. */
- segment = *table;
- if (likely(!(segment & _SEGMENT_ENTRY_INV))) {
+ segment = *segment_ptr;
+ if (!(segment & _SEGMENT_ENTRY_INV)) {
page = pfn_to_page(segment >> PAGE_SHIFT);
mp = (struct gmap_pgtable *) page->index;
return mp->vmaddr | (address & ~PMD_MASK);
} else if (segment & _SEGMENT_ENTRY_RO) {
+ mm = gmap->mm;
vmaddr = segment & _SEGMENT_ENTRY_ORIGIN;
vma = find_vma(mm, vmaddr);
if (!vma || vma->vm_start > vmaddr)
@@ -441,12 +504,12 @@ unsigned long __gmap_fault(unsigned long address, struct gmap *gmap)
/* Link gmap segment table entry location to page table. */
page = pmd_page(*pmd);
mp = (struct gmap_pgtable *) page->index;
- rmap->entry = table;
+ rmap->entry = segment_ptr;
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;
+ *segment_ptr = pmd_val(*pmd) & PAGE_MASK;
return vmaddr | (address & ~PMD_MASK);
}
return -EFAULT;