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Diffstat (limited to 'arch/s390/mm/gmap.c')
-rw-r--r--arch/s390/mm/gmap.c23
1 files changed, 8 insertions, 15 deletions
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index 05d459b638f5..54cfd51a5a27 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -815,27 +815,17 @@ static inline unsigned long *gmap_table_walk(struct gmap *gmap,
* @ptl: pointer to the spinlock pointer
*
* Returns a pointer to the locked pte for a guest address, or NULL
- *
- * Note: Can also be called for shadow gmaps.
*/
static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
spinlock_t **ptl)
{
unsigned long *table;
- if (gmap_is_shadow(gmap))
- spin_lock(&gmap->guest_table_lock);
+ BUG_ON(gmap_is_shadow(gmap));
/* Walk the gmap page table, lock and get pte pointer */
table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */
- if (!table || *table & _SEGMENT_ENTRY_INVALID) {
- if (gmap_is_shadow(gmap))
- spin_unlock(&gmap->guest_table_lock);
+ if (!table || *table & _SEGMENT_ENTRY_INVALID)
return NULL;
- }
- if (gmap_is_shadow(gmap)) {
- *ptl = &gmap->guest_table_lock;
- return pte_offset_map((pmd_t *) table, gaddr);
- }
return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl);
}
@@ -889,8 +879,6 @@ static void gmap_pte_op_end(spinlock_t *ptl)
* -EFAULT if gaddr is invalid (or mapping for shadows is missing).
*
* Called with sg->mm->mmap_sem in read.
- *
- * Note: Can also be called for shadow gmaps.
*/
static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr,
unsigned long len, int prot, unsigned long bits)
@@ -900,6 +888,7 @@ static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr,
pte_t *ptep;
int rc;
+ BUG_ON(gmap_is_shadow(gmap));
while (len) {
rc = -EAGAIN;
ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
@@ -960,7 +949,8 @@ EXPORT_SYMBOL_GPL(gmap_mprotect_notify);
* @val: pointer to the unsigned long value to return
*
* Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT
- * if reading using the virtual address failed.
+ * if reading using the virtual address failed. -EINVAL if called on a gmap
+ * shadow.
*
* Called with gmap->mm->mmap_sem in read.
*/
@@ -971,6 +961,9 @@ int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val)
pte_t *ptep, pte;
int rc;
+ if (gmap_is_shadow(gmap))
+ return -EINVAL;
+
while (1) {
rc = -EAGAIN;
ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);