Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6

* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6: (27 commits)
  [S390] Fix checkstack for s390
  [S390] fix initialization of stp
  [S390] 3215: Remove tasklet.
  [S390] console flush on panic / reboot
  [S390] introduce dirty bit for kvm live migration
  [S390] Add ioctl support for EMC Symmetrix Subsystem Control I/O
  [S390] xpram: per device block request queues.
  [S390] dasd: fix message flood for unsolicited interrupts
  [S390] Move private simple udelay function to arch/s390/lib/delay.c.
  [S390] dcssblk: add >2G DCSSs support and stacked contiguous DCSSs support.
  [S390] ptrace changes
  [S390] s390: use sys_pause for 31bit pause entry point
  [S390] qdio enhanced SIGA (iqdio) support.
  [S390] cio: fix cio_tpi.
  [S390] cio: Correct use of ! and &
  [S390] cio: inline assembly cleanup
  [S390] bus_id -> dev_set_name() for css and ccw busses
  [S390] bus_id ->dev_name() conversions in qdio
  [S390] Use s390_root_dev_* in kvm_virtio.
  [S390] more bus_id -> dev_name conversions
  ...

1 files changed, 43 insertions, 2 deletions

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 0bdb704ae051..1a928f84afd6 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -281,6 +281,9 @@ extern char empty_zero_page[PAGE_SIZE];
 #define RCP_GR_BIT	50
 #define RCP_GC_BIT	49
 
+/* User dirty bit for KVM's migration feature */
+#define KVM_UD_BIT	47
+
 #ifndef __s390x__
 
 /* Bits in the segment table address-space-control-element */
@@ -575,12 +578,16 @@ static inline void ptep_rcp_copy(pte_t *ptep)
 	unsigned long *pgste = (unsigned long *) (ptep + PTRS_PER_PTE);
 
 	skey = page_get_storage_key(page_to_phys(page));
-	if (skey & _PAGE_CHANGED)
+	if (skey & _PAGE_CHANGED) {
 		set_bit_simple(RCP_GC_BIT, pgste);
+		set_bit_simple(KVM_UD_BIT, pgste);
+	}
 	if (skey & _PAGE_REFERENCED)
 		set_bit_simple(RCP_GR_BIT, pgste);
-	if (test_and_clear_bit_simple(RCP_HC_BIT, pgste))
+	if (test_and_clear_bit_simple(RCP_HC_BIT, pgste)) {
 		SetPageDirty(page);
+		set_bit_simple(KVM_UD_BIT, pgste);
+	}
 	if (test_and_clear_bit_simple(RCP_HR_BIT, pgste))
 		SetPageReferenced(page);
 #endif
@@ -744,6 +751,40 @@ static inline pte_t pte_mkspecial(pte_t pte)
 	return pte;
 }
 
+#ifdef CONFIG_PGSTE
+/*
+ * Get (and clear) the user dirty bit for a PTE.
+ */
+static inline int kvm_s390_test_and_clear_page_dirty(struct mm_struct *mm,
+						     pte_t *ptep)
+{
+	int dirty;
+	unsigned long *pgste;
+	struct page *page;
+	unsigned int skey;
+
+	if (!mm->context.pgstes)
+		return -EINVAL;
+	rcp_lock(ptep);
+	pgste = (unsigned long *) (ptep + PTRS_PER_PTE);
+	page = virt_to_page(pte_val(*ptep));
+	skey = page_get_storage_key(page_to_phys(page));
+	if (skey & _PAGE_CHANGED) {
+		set_bit_simple(RCP_GC_BIT, pgste);
+		set_bit_simple(KVM_UD_BIT, pgste);
+	}
+	if (test_and_clear_bit_simple(RCP_HC_BIT, pgste)) {
+		SetPageDirty(page);
+		set_bit_simple(KVM_UD_BIT, pgste);
+	}
+	dirty = test_and_clear_bit_simple(KVM_UD_BIT, pgste);
+	if (skey & _PAGE_CHANGED)
+		page_clear_dirty(page);
+	rcp_unlock(ptep);
+	return dirty;
+}
+#endif
+
 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
 					    unsigned long addr, pte_t *ptep)