Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/mm: Lockless get_user_pages_fast() for 64-bit (v3)
  powerpc: Don't use the wrong thread_struct for ptrace get/set VSX regs
  powerpc: Fix ptrace buffer size for VSX
  powerpc: Correctly hookup PTRACE_GET/SETVSRREGS for 32 bit processes
  ide/powermac: Fix use of uninitialized pointer on media-bay
  powerpc: Allow non-hcall return values for lparcfg writes
  ipmi/powerpc: Use linux/of_{device,platform}.h instead of asm
  powerpc/fsl: proliferate simple-bus compatibility to soc nodes
  Documentation: remove old sbc8260 board specific information
  cpm2: Rework baud rate generators configuration to support external clocks.
  powerpc: rtc_cmos_setup: assign interrupts only if there is i8259 PIC
  cpm_uart: Add generic clock API support to set baudrates
  cpm_uart: Modem control lines support
  powerpc: implement GPIO LIB API on CPM1 Freescale SoC.
  cpm2: Implement GPIO LIB API on CPM2 Freescale SoC.
  powerpc: Fix 8xx build failure
  powerpc: clean up the Book-E HW watchpoint support

1 files changed, 23 insertions, 0 deletions

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index a39b38ccdc9..69ed3cb1197 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -143,6 +143,29 @@ static inline int page_cache_get_speculative(struct page *page)
 	return 1;
 }
 
+/*
+ * Same as above, but add instead of inc (could just be merged)
+ */
+static inline int page_cache_add_speculative(struct page *page, int count)
+{
+	VM_BUG_ON(in_interrupt());
+
+#if !defined(CONFIG_SMP) && defined(CONFIG_CLASSIC_RCU)
+# ifdef CONFIG_PREEMPT
+	VM_BUG_ON(!in_atomic());
+# endif
+	VM_BUG_ON(page_count(page) == 0);
+	atomic_add(count, &page->_count);
+
+#else
+	if (unlikely(!atomic_add_unless(&page->_count, count, 0)))
+		return 0;
+#endif
+	VM_BUG_ON(PageCompound(page) && page != compound_head(page));
+
+	return 1;
+}
+
 static inline int page_freeze_refs(struct page *page, int count)
 {
 	return likely(atomic_cmpxchg(&page->_count, count, 0) == count);