Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "Here's the usual mixed bag of arm64 updates, also including some
  related EFI changes (Acked by Matt) and the MMU gather range cleanup
  (Acked by you).

  Changes include:
   - support for alternative instruction patching from Andre
   - seccomp from Akashi
   - some AArch32 instruction emulation, required by the Android folks
   - optimisations for exception entry/exit code, cmpxchg, pcpu atomics
   - mmu_gather range calculations moved into core code
   - EFI updates from Ard, including long-awaited SMBIOS support
   - /proc/cpuinfo fixes to align with the format used by arch/arm/
   - a few non-critical fixes across the architecture"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (70 commits)
  arm64: remove the unnecessary arm64_swiotlb_init()
  arm64: add module support for alternatives fixups
  arm64: perf: Prevent wraparound during overflow
  arm64/include/asm: Fixed a warning about 'struct pt_regs'
  arm64: Provide a namespace to NCAPS
  arm64: bpf: lift restriction on last instruction
  arm64: Implement support for read-mostly sections
  arm64: compat: align cacheflush syscall with arch/arm
  arm64: add seccomp support
  arm64: add SIGSYS siginfo for compat task
  arm64: add seccomp syscall for compat task
  asm-generic: add generic seccomp.h for secure computing mode 1
  arm64: ptrace: allow tracer to skip a system call
  arm64: ptrace: add NT_ARM_SYSTEM_CALL regset
  arm64: Move some head.text functions to executable section
  arm64: jump labels: NOP out NOP -> NOP replacement
  arm64: add support to dump the kernel page tables
  arm64: Add FIX_HOLE to permanent fixed addresses
  arm64: alternatives: fix pr_fmt string for consistency
  arm64: vmlinux.lds.S: don't discard .exit.* sections at link-time
  ...

1 files changed, 73 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/cmpxchg.h b/arch/arm64/include/asm/cmpxchg.h
index ddb9d7830558..cb9593079f29 100644
--- a/arch/arm64/include/asm/cmpxchg.h
+++ b/arch/arm64/include/asm/cmpxchg.h
@@ -19,6 +19,7 @@
 #define __ASM_CMPXCHG_H
 
 #include <linux/bug.h>
+#include <linux/mmdebug.h>
 
 #include <asm/barrier.h>
 
@@ -152,6 +153,51 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
 	return oldval;
 }
 
+#define system_has_cmpxchg_double()     1
+
+static inline int __cmpxchg_double(volatile void *ptr1, volatile void *ptr2,
+		unsigned long old1, unsigned long old2,
+		unsigned long new1, unsigned long new2, int size)
+{
+	unsigned long loop, lost;
+
+	switch (size) {
+	case 8:
+		VM_BUG_ON((unsigned long *)ptr2 - (unsigned long *)ptr1 != 1);
+		do {
+			asm volatile("// __cmpxchg_double8\n"
+			"	ldxp	%0, %1, %2\n"
+			"	eor	%0, %0, %3\n"
+			"	eor	%1, %1, %4\n"
+			"	orr	%1, %0, %1\n"
+			"	mov	%w0, #0\n"
+			"	cbnz	%1, 1f\n"
+			"	stxp	%w0, %5, %6, %2\n"
+			"1:\n"
+				: "=&r"(loop), "=&r"(lost), "+Q" (*(u64 *)ptr1)
+				: "r" (old1), "r"(old2), "r"(new1), "r"(new2));
+		} while (loop);
+		break;
+	default:
+		BUILD_BUG();
+	}
+
+	return !lost;
+}
+
+static inline int __cmpxchg_double_mb(volatile void *ptr1, volatile void *ptr2,
+			unsigned long old1, unsigned long old2,
+			unsigned long new1, unsigned long new2, int size)
+{
+	int ret;
+
+	smp_mb();
+	ret = __cmpxchg_double(ptr1, ptr2, old1, old2, new1, new2, size);
+	smp_mb();
+
+	return ret;
+}
+
 static inline unsigned long __cmpxchg_mb(volatile void *ptr, unsigned long old,
 					 unsigned long new, int size)
 {
@@ -182,6 +228,33 @@ static inline unsigned long __cmpxchg_mb(volatile void *ptr, unsigned long old,
 	__ret; \
 })
 
+#define cmpxchg_double(ptr1, ptr2, o1, o2, n1, n2) \
+({\
+	int __ret;\
+	__ret = __cmpxchg_double_mb((ptr1), (ptr2), (unsigned long)(o1), \
+			(unsigned long)(o2), (unsigned long)(n1), \
+			(unsigned long)(n2), sizeof(*(ptr1)));\
+	__ret; \
+})
+
+#define cmpxchg_double_local(ptr1, ptr2, o1, o2, n1, n2) \
+({\
+	int __ret;\
+	__ret = __cmpxchg_double((ptr1), (ptr2), (unsigned long)(o1), \
+			(unsigned long)(o2), (unsigned long)(n1), \
+			(unsigned long)(n2), sizeof(*(ptr1)));\
+	__ret; \
+})
+
+#define this_cpu_cmpxchg_1(ptr, o, n) cmpxchg_local(raw_cpu_ptr(&(ptr)), o, n)
+#define this_cpu_cmpxchg_2(ptr, o, n) cmpxchg_local(raw_cpu_ptr(&(ptr)), o, n)
+#define this_cpu_cmpxchg_4(ptr, o, n) cmpxchg_local(raw_cpu_ptr(&(ptr)), o, n)
+#define this_cpu_cmpxchg_8(ptr, o, n) cmpxchg_local(raw_cpu_ptr(&(ptr)), o, n)
+
+#define this_cpu_cmpxchg_double_8(ptr1, ptr2, o1, o2, n1, n2) \
+	cmpxchg_double_local(raw_cpu_ptr(&(ptr1)), raw_cpu_ptr(&(ptr2)), \
+				o1, o2, n1, n2)
+
 #define cmpxchg64(ptr,o,n)		cmpxchg((ptr),(o),(n))
 #define cmpxchg64_local(ptr,o,n)	cmpxchg_local((ptr),(o),(n))