x86/mm: Add INVPCID helpers

commit 060a402a1ddb551455ee410de2eadd3349f2801b upstream.

This adds helpers for each of the four currently-specified INVPCID
modes.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/8a62b23ad686888cee01da134c91409e22064db9.1454096309.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index a7973dd..2208909 100644 (file)
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -7,6 +7,54 @@
 #include <asm/processor.h>
 #include <asm/system.h>
 
+static inline void __invpcid(unsigned long pcid, unsigned long addr,
+                            unsigned long type)
+{
+       u64 desc[2] = { pcid, addr };
+
+       /*
+        * The memory clobber is because the whole point is to invalidate
+        * stale TLB entries and, especially if we're flushing global
+        * mappings, we don't want the compiler to reorder any subsequent
+        * memory accesses before the TLB flush.
+        *
+        * The hex opcode is invpcid (%ecx), %eax in 32-bit mode and
+        * invpcid (%rcx), %rax in long mode.
+        */
+       asm volatile (".byte 0x66, 0x0f, 0x38, 0x82, 0x01"
+                     : : "m" (desc), "a" (type), "c" (desc) : "memory");
+}
+
+#define INVPCID_TYPE_INDIV_ADDR                0
+#define INVPCID_TYPE_SINGLE_CTXT       1
+#define INVPCID_TYPE_ALL_INCL_GLOBAL   2
+#define INVPCID_TYPE_ALL_NON_GLOBAL    3
+
+/* Flush all mappings for a given pcid and addr, not including globals. */
+static inline void invpcid_flush_one(unsigned long pcid,
+                                    unsigned long addr)
+{
+       __invpcid(pcid, addr, INVPCID_TYPE_INDIV_ADDR);
+}
+
+/* Flush all mappings for a given PCID, not including globals. */
+static inline void invpcid_flush_single_context(unsigned long pcid)
+{
+       __invpcid(pcid, 0, INVPCID_TYPE_SINGLE_CTXT);
+}
+
+/* Flush all mappings, including globals, for all PCIDs. */
+static inline void invpcid_flush_all(void)
+{
+       __invpcid(0, 0, INVPCID_TYPE_ALL_INCL_GLOBAL);
+}
+
+/* Flush all mappings for all PCIDs except globals. */
+static inline void invpcid_flush_all_nonglobals(void)
+{
+       __invpcid(0, 0, INVPCID_TYPE_ALL_NON_GLOBAL);
+}
+
 #ifdef CONFIG_PARAVIRT
 #include <asm/paravirt.h>
 #else