Merge commit 'origin/master' into next

Manual merge of:
	arch/powerpc/include/asm/elf.h
	drivers/i2c/busses/i2c-mpc.c

1 files changed, 63 insertions, 189 deletions

diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index 05794c566e8..02f496a8dba 100644
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -1,174 +1,45 @@
 /*
-	Asm versions of Xen pv-ops, suitable for either direct use or inlining.
-	The inline versions are the same as the direct-use versions, with the
-	pre- and post-amble chopped off.
-
-	This code is encoded for size rather than absolute efficiency,
-	with a view to being able to inline as much as possible.
-
-	We only bother with direct forms (ie, vcpu in pda) of the operations
-	here; the indirect forms are better handled in C, since they're
-	generally too large to inline anyway.
+ * Asm versions of Xen pv-ops, suitable for either direct use or
+ * inlining.  The inline versions are the same as the direct-use
+ * versions, with the pre- and post-amble chopped off.
+ *
+ * This code is encoded for size rather than absolute efficiency, with
+ * a view to being able to inline as much as possible.
+ *
+ * We only bother with direct forms (ie, vcpu in pda) of the
+ * operations here; the indirect forms are better handled in C, since
+ * they're generally too large to inline anyway.
  */
 
-#include <linux/linkage.h>
-
-#include <asm/asm-offsets.h>
-#include <asm/processor-flags.h>
 #include <asm/errno.h>
+#include <asm/percpu.h>
+#include <asm/processor-flags.h>
 #include <asm/segment.h>
 
 #include <xen/interface/xen.h>
 
-#define RELOC(x, v)	.globl x##_reloc; x##_reloc=v
-#define ENDPATCH(x)	.globl x##_end; x##_end=.
-
-/* Pseudo-flag used for virtual NMI, which we don't implement yet */
-#define XEN_EFLAGS_NMI	0x80000000
-
-#if 1
-/*
-	x86-64 does not yet support direct access to percpu variables
-	via a segment override, so we just need to make sure this code
-	never gets used
- */
-#define BUG			ud2a
-#define PER_CPU_VAR(var, off)	0xdeadbeef
-#endif
-
-/*
-	Enable events.  This clears the event mask and tests the pending
-	event status with one and operation.  If there are pending
-	events, then enter the hypervisor to get them handled.
- */
-ENTRY(xen_irq_enable_direct)
-	BUG
-
-	/* Unmask events */
-	movb $0, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
-
-	/* Preempt here doesn't matter because that will deal with
-	   any pending interrupts.  The pending check may end up being
-	   run on the wrong CPU, but that doesn't hurt. */
-
-	/* Test for pending */
-	testb $0xff, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_pending)
-	jz 1f
-
-2:	call check_events
-1:
-ENDPATCH(xen_irq_enable_direct)
-	ret
-	ENDPROC(xen_irq_enable_direct)
-	RELOC(xen_irq_enable_direct, 2b+1)
-
-/*
-	Disabling events is simply a matter of making the event mask
-	non-zero.
- */
-ENTRY(xen_irq_disable_direct)
-	BUG
-
-	movb $1, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
-ENDPATCH(xen_irq_disable_direct)
-	ret
-	ENDPROC(xen_irq_disable_direct)
-	RELOC(xen_irq_disable_direct, 0)
-
-/*
-	(xen_)save_fl is used to get the current interrupt enable status.
-	Callers expect the status to be in X86_EFLAGS_IF, and other bits
-	may be set in the return value.  We take advantage of this by
-	making sure that X86_EFLAGS_IF has the right value (and other bits
-	in that byte are 0), but other bits in the return value are
-	undefined.  We need to toggle the state of the bit, because
-	Xen and x86 use opposite senses (mask vs enable).
- */
-ENTRY(xen_save_fl_direct)
-	BUG
-
-	testb $0xff, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
-	setz %ah
-	addb %ah,%ah
-ENDPATCH(xen_save_fl_direct)
-	ret
-	ENDPROC(xen_save_fl_direct)
-	RELOC(xen_save_fl_direct, 0)
-
-/*
-	In principle the caller should be passing us a value return
-	from xen_save_fl_direct, but for robustness sake we test only
-	the X86_EFLAGS_IF flag rather than the whole byte. After
-	setting the interrupt mask state, it checks for unmasked
-	pending events and enters the hypervisor to get them delivered
-	if so.
- */
-ENTRY(xen_restore_fl_direct)
-	BUG
-
-	testb $X86_EFLAGS_IF>>8, %ah
-	setz PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask)
-	/* Preempt here doesn't matter because that will deal with
-	   any pending interrupts.  The pending check may end up being
-	   run on the wrong CPU, but that doesn't hurt. */
-
-	/* check for unmasked and pending */
-	cmpw $0x0001, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_pending)
-	jz 1f
-2:	call check_events
-1:
-ENDPATCH(xen_restore_fl_direct)
-	ret
-	ENDPROC(xen_restore_fl_direct)
-	RELOC(xen_restore_fl_direct, 2b+1)
-
-
-/*
-	Force an event check by making a hypercall,
-	but preserve regs before making the call.
- */
-check_events:
-	push %rax
-	push %rcx
-	push %rdx
-	push %rsi
-	push %rdi
-	push %r8
-	push %r9
-	push %r10
-	push %r11
-	call xen_force_evtchn_callback
-	pop %r11
-	pop %r10
-	pop %r9
-	pop %r8
-	pop %rdi
-	pop %rsi
-	pop %rdx
-	pop %rcx
-	pop %rax
-	ret
+#include "xen-asm.h"
 
 ENTRY(xen_adjust_exception_frame)
-	mov 8+0(%rsp),%rcx
-	mov 8+8(%rsp),%r11
+	mov 8+0(%rsp), %rcx
+	mov 8+8(%rsp), %r11
 	ret $16
 
 hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32
 /*
-	Xen64 iret frame:
-
-	ss
-	rsp
-	rflags
-	cs
-	rip		<-- standard iret frame
-
-	flags
-
-	rcx		}
-	r11		}<-- pushed by hypercall page
-rsp ->	rax		}
+ * Xen64 iret frame:
+ *
+ *	ss
+ *	rsp
+ *	rflags
+ *	cs
+ *	rip		<-- standard iret frame
+ *
+ *	flags
+ *
+ *	rcx		}
+ *	r11		}<-- pushed by hypercall page
+ * rsp->rax		}
  */
 ENTRY(xen_iret)
 	pushq $0
@@ -177,8 +48,8 @@ ENDPATCH(xen_iret)
 RELOC(xen_iret, 1b+1)
 
 /*
-	sysexit is not used for 64-bit processes, so it's
-	only ever used to return to 32-bit compat userspace.
+ * sysexit is not used for 64-bit processes, so it's only ever used to
+ * return to 32-bit compat userspace.
  */
 ENTRY(xen_sysexit)
 	pushq $__USER32_DS
@@ -193,13 +64,15 @@ ENDPATCH(xen_sysexit)
 RELOC(xen_sysexit, 1b+1)
 
 ENTRY(xen_sysret64)
-	/* We're already on the usermode stack at this point, but still
-	   with the kernel gs, so we can easily switch back */
-	movq %rsp, %gs:pda_oldrsp
-	movq %gs:pda_kernelstack,%rsp
+	/*
+	 * We're already on the usermode stack at this point, but
+	 * still with the kernel gs, so we can easily switch back
+	 */
+	movq %rsp, PER_CPU_VAR(old_rsp)
+	movq PER_CPU_VAR(kernel_stack), %rsp
 
 	pushq $__USER_DS
-	pushq %gs:pda_oldrsp
+	pushq PER_CPU_VAR(old_rsp)
 	pushq %r11
 	pushq $__USER_CS
 	pushq %rcx
@@ -210,13 +83,15 @@ ENDPATCH(xen_sysret64)
 RELOC(xen_sysret64, 1b+1)
 
 ENTRY(xen_sysret32)
-	/* We're already on the usermode stack at this point, but still
-	   with the kernel gs, so we can easily switch back */
-	movq %rsp, %gs:pda_oldrsp
-	movq %gs:pda_kernelstack, %rsp
+	/*
+	 * We're already on the usermode stack at this point, but
+	 * still with the kernel gs, so we can easily switch back
+	 */
+	movq %rsp, PER_CPU_VAR(old_rsp)
+	movq PER_CPU_VAR(kernel_stack), %rsp
 
 	pushq $__USER32_DS
-	pushq %gs:pda_oldrsp
+	pushq PER_CPU_VAR(old_rsp)
 	pushq %r11
 	pushq $__USER32_CS
 	pushq %rcx
@@ -227,28 +102,27 @@ ENDPATCH(xen_sysret32)
 RELOC(xen_sysret32, 1b+1)
 
 /*
-	Xen handles syscall callbacks much like ordinary exceptions,
-	which means we have:
-	 - kernel gs
-	 - kernel rsp
-	 - an iret-like stack frame on the stack (including rcx and r11):
-		ss
-		rsp
-		rflags
-		cs
-		rip
-		r11
-	rsp->	rcx
-
-	In all the entrypoints, we undo all that to make it look
-	like a CPU-generated syscall/sysenter and jump to the normal
-	entrypoint.
+ * Xen handles syscall callbacks much like ordinary exceptions, which
+ * means we have:
+ * - kernel gs
+ * - kernel rsp
+ * - an iret-like stack frame on the stack (including rcx and r11):
+ *	ss
+ *	rsp
+ *	rflags
+ *	cs
+ *	rip
+ *	r11
+ * rsp->rcx
+ *
+ * In all the entrypoints, we undo all that to make it look like a
+ * CPU-generated syscall/sysenter and jump to the normal entrypoint.
  */
 
 .macro undo_xen_syscall
-	mov 0*8(%rsp),%rcx
-	mov 1*8(%rsp),%r11
-	mov 5*8(%rsp),%rsp
+	mov 0*8(%rsp), %rcx
+	mov 1*8(%rsp), %r11
+	mov 5*8(%rsp), %rsp
 .endm
 
 /* Normal 64-bit system call target */
@@ -275,7 +149,7 @@ ENDPROC(xen_sysenter_target)
 
 ENTRY(xen_syscall32_target)
 ENTRY(xen_sysenter_target)
-	lea 16(%rsp), %rsp	/* strip %rcx,%r11 */
+	lea 16(%rsp), %rsp	/* strip %rcx, %r11 */
 	mov $-ENOSYS, %rax
 	pushq $VGCF_in_syscall
 	jmp hypercall_iret