x86/asm/entry: Move the compat syscall entry code to arch/x86/entry/

Move the ia32entry.S file over into arch/x86/entry/.

Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 1 insertions, 523 deletions

diff --git a/arch/x86/ia32/Makefile b/arch/x86/ia32/Makefile
index bb635c641869..cd4339bae066 100644
--- a/arch/x86/ia32/Makefile
+++ b/arch/x86/ia32/Makefile
@@ -2,7 +2,7 @@
 # Makefile for the ia32 kernel emulation subsystem.
 #
 
-obj-$(CONFIG_IA32_EMULATION) := ia32entry.o sys_ia32.o ia32_signal.o
+obj-$(CONFIG_IA32_EMULATION) := sys_ia32.o ia32_signal.o
 
 obj-$(CONFIG_IA32_AOUT) += ia32_aout.o
 
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
deleted file mode 100644
index 2be23c734db5..000000000000
--- a/arch/x86/ia32/ia32entry.S
+++ /dev/null
@@ -1,522 +0,0 @@
-/*
- * Compatibility mode system call entry point for x86-64. 
- * 		
- * Copyright 2000-2002 Andi Kleen, SuSE Labs.
- */		 
-
-#include <asm/calling.h>
-#include <asm/asm-offsets.h>
-#include <asm/current.h>
-#include <asm/errno.h>
-#include <asm/ia32_unistd.h>	
-#include <asm/thread_info.h>	
-#include <asm/segment.h>
-#include <asm/irqflags.h>
-#include <asm/asm.h>
-#include <asm/smap.h>
-#include <linux/linkage.h>
-#include <linux/err.h>
-
-/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this.  */
-#include <linux/elf-em.h>
-#define AUDIT_ARCH_I386		(EM_386|__AUDIT_ARCH_LE)
-#define __AUDIT_ARCH_LE	   0x40000000
-
-#ifndef CONFIG_AUDITSYSCALL
-#define sysexit_audit ia32_ret_from_sys_call
-#define sysretl_audit ia32_ret_from_sys_call
-#endif
-
-	.section .entry.text, "ax"
-
-	/* clobbers %rax */
-	.macro  CLEAR_RREGS _r9=rax
-	xorl 	%eax,%eax
-	movq	%rax,R11(%rsp)
-	movq	%rax,R10(%rsp)
-	movq	%\_r9,R9(%rsp)
-	movq	%rax,R8(%rsp)
-	.endm
-
-	/*
-	 * Reload arg registers from stack in case ptrace changed them.
-	 * We don't reload %eax because syscall_trace_enter() returned
-	 * the %rax value we should see.  Instead, we just truncate that
-	 * value to 32 bits again as we did on entry from user mode.
-	 * If it's a new value set by user_regset during entry tracing,
-	 * this matches the normal truncation of the user-mode value.
-	 * If it's -1 to make us punt the syscall, then (u32)-1 is still
-	 * an appropriately invalid value.
-	 */
-	.macro LOAD_ARGS32 _r9=0
-	.if \_r9
-	movl R9(%rsp),%r9d
-	.endif
-	movl RCX(%rsp),%ecx
-	movl RDX(%rsp),%edx
-	movl RSI(%rsp),%esi
-	movl RDI(%rsp),%edi
-	movl %eax,%eax			/* zero extension */
-	.endm
-	
-
-#ifdef CONFIG_PARAVIRT
-ENTRY(native_usergs_sysret32)
-	swapgs
-	sysretl
-ENDPROC(native_usergs_sysret32)
-#endif
-
-/*
- * 32bit SYSENTER instruction entry.
- *
- * SYSENTER loads ss, rsp, cs, and rip from previously programmed MSRs.
- * IF and VM in rflags are cleared (IOW: interrupts are off).
- * SYSENTER does not save anything on the stack,
- * and does not save old rip (!!!) and rflags.
- *
- * Arguments:
- * eax  system call number
- * ebx  arg1
- * ecx  arg2
- * edx  arg3
- * esi  arg4
- * edi  arg5
- * ebp  user stack
- * 0(%ebp) arg6
- *
- * This is purely a fast path. For anything complicated we use the int 0x80
- * path below. We set up a complete hardware stack frame to share code
- * with the int 0x80 path.
- */
-ENTRY(ia32_sysenter_target)
-	/*
-	 * Interrupts are off on entry.
-	 * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
-	 * it is too small to ever cause noticeable irq latency.
-	 */
-	SWAPGS_UNSAFE_STACK
-	movq	PER_CPU_VAR(cpu_current_top_of_stack), %rsp
-	ENABLE_INTERRUPTS(CLBR_NONE)
-
-	/* Zero-extending 32-bit regs, do not remove */
-	movl	%ebp, %ebp
-	movl	%eax, %eax
-
-	movl	ASM_THREAD_INFO(TI_sysenter_return, %rsp, 0), %r10d
-
-	/* Construct struct pt_regs on stack */
-	pushq	$__USER32_DS		/* pt_regs->ss */
-	pushq	%rbp			/* pt_regs->sp */
-	pushfq				/* pt_regs->flags */
-	pushq	$__USER32_CS		/* pt_regs->cs */
-	pushq	%r10 /* pt_regs->ip = thread_info->sysenter_return */
-	pushq	%rax			/* pt_regs->orig_ax */
-	pushq	%rdi			/* pt_regs->di */
-	pushq	%rsi			/* pt_regs->si */
-	pushq	%rdx			/* pt_regs->dx */
-	pushq	%rcx			/* pt_regs->cx */
-	pushq	$-ENOSYS		/* pt_regs->ax */
-	cld
-	sub	$(10*8),%rsp /* pt_regs->r8-11,bp,bx,r12-15 not saved */
-
-	/*
-	 * no need to do an access_ok check here because rbp has been
-	 * 32bit zero extended
-	 */
-	ASM_STAC
-1:	movl	(%rbp),%ebp
-	_ASM_EXTABLE(1b,ia32_badarg)
-	ASM_CLAC
-
-	/*
-	 * Sysenter doesn't filter flags, so we need to clear NT
-	 * ourselves.  To save a few cycles, we can check whether
-	 * NT was set instead of doing an unconditional popfq.
-	 */
-	testl $X86_EFLAGS_NT,EFLAGS(%rsp)
-	jnz sysenter_fix_flags
-sysenter_flags_fixed:
-
-	orl     $TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS)
-	testl   $_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jnz  sysenter_tracesys
-
-sysenter_do_call:
-	/* 32bit syscall -> 64bit C ABI argument conversion */
-	movl	%edi,%r8d	/* arg5 */
-	movl	%ebp,%r9d	/* arg6 */
-	xchg	%ecx,%esi	/* rsi:arg2, rcx:arg4 */
-	movl	%ebx,%edi	/* arg1 */
-	movl	%edx,%edx	/* arg3 (zero extension) */
-sysenter_dispatch:
-	cmpq	$(IA32_NR_syscalls-1),%rax
-	ja	1f
-	call	*ia32_sys_call_table(,%rax,8)
-	movq	%rax,RAX(%rsp)
-1:
-	DISABLE_INTERRUPTS(CLBR_NONE)
-	TRACE_IRQS_OFF
-	testl	$_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jnz	sysexit_audit
-sysexit_from_sys_call:
-	/*
-	 * NB: SYSEXIT is not obviously safe for 64-bit kernels -- an
-	 * NMI between STI and SYSEXIT has poorly specified behavior,
-	 * and and NMI followed by an IRQ with usergs is fatal.  So
-	 * we just pretend we're using SYSEXIT but we really use
-	 * SYSRETL instead.
-	 *
-	 * This code path is still called 'sysexit' because it pairs
-	 * with 'sysenter' and it uses the SYSENTER calling convention.
-	 */
-	andl    $~TS_COMPAT,ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS)
-	movl	RIP(%rsp),%ecx		/* User %eip */
-	RESTORE_RSI_RDI
-	xorl	%edx,%edx		/* avoid info leaks */
-	xorq	%r8,%r8
-	xorq	%r9,%r9
-	xorq	%r10,%r10
-	movl	EFLAGS(%rsp),%r11d	/* User eflags */
-	TRACE_IRQS_ON
-
-	/*
-	 * SYSRETL works even on Intel CPUs.  Use it in preference to SYSEXIT,
-	 * since it avoids a dicey window with interrupts enabled.
-	 */
-	movl	RSP(%rsp),%esp
-
-	/*
-	 * USERGS_SYSRET32 does:
-	 *  gsbase = user's gs base
-	 *  eip = ecx
-	 *  rflags = r11
-	 *  cs = __USER32_CS
-	 *  ss = __USER_DS
-	 *
-	 * The prologue set RIP(%rsp) to VDSO32_SYSENTER_RETURN, which does:
-	 *
-	 *  pop %ebp
-	 *  pop %edx
-	 *  pop %ecx
-	 *
-	 * Therefore, we invoke SYSRETL with EDX and R8-R10 zeroed to
-	 * avoid info leaks.  R11 ends up with VDSO32_SYSENTER_RETURN's
-	 * address (already known to user code), and R12-R15 are
-	 * callee-saved and therefore don't contain any interesting
-	 * kernel data.
-	 */
-	USERGS_SYSRET32
-
-#ifdef CONFIG_AUDITSYSCALL
-	.macro auditsys_entry_common
-	movl %esi,%r8d			/* 5th arg: 4th syscall arg */
-	movl %ecx,%r9d			/*swap with edx*/
-	movl %edx,%ecx			/* 4th arg: 3rd syscall arg */
-	movl %r9d,%edx			/* 3rd arg: 2nd syscall arg */
-	movl %ebx,%esi			/* 2nd arg: 1st syscall arg */
-	movl %eax,%edi			/* 1st arg: syscall number */
-	call __audit_syscall_entry
-	movl ORIG_RAX(%rsp),%eax	/* reload syscall number */
-	movl %ebx,%edi			/* reload 1st syscall arg */
-	movl RCX(%rsp),%esi	/* reload 2nd syscall arg */
-	movl RDX(%rsp),%edx	/* reload 3rd syscall arg */
-	movl RSI(%rsp),%ecx	/* reload 4th syscall arg */
-	movl RDI(%rsp),%r8d	/* reload 5th syscall arg */
-	.endm
-
-	.macro auditsys_exit exit
-	testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jnz ia32_ret_from_sys_call
-	TRACE_IRQS_ON
-	ENABLE_INTERRUPTS(CLBR_NONE)
-	movl %eax,%esi		/* second arg, syscall return value */
-	cmpl $-MAX_ERRNO,%eax	/* is it an error ? */
-	jbe 1f
-	movslq %eax, %rsi	/* if error sign extend to 64 bits */
-1:	setbe %al		/* 1 if error, 0 if not */
-	movzbl %al,%edi		/* zero-extend that into %edi */
-	call __audit_syscall_exit
-	movq RAX(%rsp),%rax	/* reload syscall return value */
-	movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi
-	DISABLE_INTERRUPTS(CLBR_NONE)
-	TRACE_IRQS_OFF
-	testl %edi, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jz \exit
-	CLEAR_RREGS
-	jmp int_with_check
-	.endm
-
-sysenter_auditsys:
-	auditsys_entry_common
-	movl %ebp,%r9d			/* reload 6th syscall arg */
-	jmp sysenter_dispatch
-
-sysexit_audit:
-	auditsys_exit sysexit_from_sys_call
-#endif
-
-sysenter_fix_flags:
-	pushq $(X86_EFLAGS_IF|X86_EFLAGS_FIXED)
-	popfq
-	jmp sysenter_flags_fixed
-
-sysenter_tracesys:
-#ifdef CONFIG_AUDITSYSCALL
-	testl	$(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT), ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jz	sysenter_auditsys
-#endif
-	SAVE_EXTRA_REGS
-	CLEAR_RREGS
-	movq	%rsp,%rdi        /* &pt_regs -> arg1 */
-	call	syscall_trace_enter
-	LOAD_ARGS32  /* reload args from stack in case ptrace changed it */
-	RESTORE_EXTRA_REGS
-	jmp	sysenter_do_call
-ENDPROC(ia32_sysenter_target)
-
-/*
- * 32bit SYSCALL instruction entry.
- *
- * 32bit SYSCALL saves rip to rcx, clears rflags.RF, then saves rflags to r11,
- * then loads new ss, cs, and rip from previously programmed MSRs.
- * rflags gets masked by a value from another MSR (so CLD and CLAC
- * are not needed). SYSCALL does not save anything on the stack
- * and does not change rsp.
- *
- * Note: rflags saving+masking-with-MSR happens only in Long mode
- * (in legacy 32bit mode, IF, RF and VM bits are cleared and that's it).
- * Don't get confused: rflags saving+masking depends on Long Mode Active bit
- * (EFER.LMA=1), NOT on bitness of userspace where SYSCALL executes
- * or target CS descriptor's L bit (SYSCALL does not read segment descriptors).
- *
- * Arguments:
- * eax  system call number
- * ecx  return address
- * ebx  arg1
- * ebp  arg2	(note: not saved in the stack frame, should not be touched)
- * edx  arg3
- * esi  arg4
- * edi  arg5
- * esp  user stack
- * 0(%esp) arg6
- *
- * This is purely a fast path. For anything complicated we use the int 0x80
- * path below. We set up a complete hardware stack frame to share code
- * with the int 0x80 path.
- */
-ENTRY(ia32_cstar_target)
-	/*
-	 * Interrupts are off on entry.
-	 * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
-	 * it is too small to ever cause noticeable irq latency.
-	 */
-	SWAPGS_UNSAFE_STACK
-	movl	%esp,%r8d
-	movq	PER_CPU_VAR(cpu_current_top_of_stack),%rsp
-	ENABLE_INTERRUPTS(CLBR_NONE)
-
-	/* Zero-extending 32-bit regs, do not remove */
-	movl	%eax,%eax
-
-	/* Construct struct pt_regs on stack */
-	pushq	$__USER32_DS		/* pt_regs->ss */
-	pushq	%r8			/* pt_regs->sp */
-	pushq	%r11			/* pt_regs->flags */
-	pushq	$__USER32_CS		/* pt_regs->cs */
-	pushq	%rcx			/* pt_regs->ip */
-	pushq	%rax			/* pt_regs->orig_ax */
-	pushq	%rdi			/* pt_regs->di */
-	pushq	%rsi			/* pt_regs->si */
-	pushq	%rdx			/* pt_regs->dx */
-	pushq	%rbp			/* pt_regs->cx */
-	movl	%ebp,%ecx
-	pushq	$-ENOSYS		/* pt_regs->ax */
-	sub	$(10*8),%rsp /* pt_regs->r8-11,bp,bx,r12-15 not saved */
-
-	/*
-	 * no need to do an access_ok check here because r8 has been
-	 * 32bit zero extended
-	 */
-	ASM_STAC
-1:	movl	(%r8),%r9d
-	_ASM_EXTABLE(1b,ia32_badarg)
-	ASM_CLAC
-	orl     $TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS)
-	testl   $_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jnz   cstar_tracesys
-
-cstar_do_call:
-	/* 32bit syscall -> 64bit C ABI argument conversion */
-	movl	%edi,%r8d	/* arg5 */
-	/* r9 already loaded */	/* arg6 */
-	xchg	%ecx,%esi	/* rsi:arg2, rcx:arg4 */
-	movl	%ebx,%edi	/* arg1 */
-	movl	%edx,%edx	/* arg3 (zero extension) */
-cstar_dispatch:
-	cmpq	$(IA32_NR_syscalls-1),%rax
-	ja	1f
-	call *ia32_sys_call_table(,%rax,8)
-	movq %rax,RAX(%rsp)
-1:
-	DISABLE_INTERRUPTS(CLBR_NONE)
-	TRACE_IRQS_OFF
-	testl $_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jnz sysretl_audit
-sysretl_from_sys_call:
-	andl $~TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS)
-	RESTORE_RSI_RDI_RDX
-	movl RIP(%rsp),%ecx
-	movl EFLAGS(%rsp),%r11d
-	xorq	%r10,%r10
-	xorq	%r9,%r9
-	xorq	%r8,%r8
-	TRACE_IRQS_ON
-	movl RSP(%rsp),%esp
-	/*
-	 * 64bit->32bit SYSRET restores eip from ecx,
-	 * eflags from r11 (but RF and VM bits are forced to 0),
-	 * cs and ss are loaded from MSRs.
-	 * (Note: 32bit->32bit SYSRET is different: since r11
-	 * does not exist, it merely sets eflags.IF=1).
-	 *
-	 * NB: On AMD CPUs with the X86_BUG_SYSRET_SS_ATTRS bug, the ss
-	 * descriptor is not reinitialized.  This means that we must
-	 * avoid SYSRET with SS == NULL, which could happen if we schedule,
-	 * exit the kernel, and re-enter using an interrupt vector.  (All
-	 * interrupt entries on x86_64 set SS to NULL.)  We prevent that
-	 * from happening by reloading SS in __switch_to.
-	 */
-	USERGS_SYSRET32
-
-#ifdef CONFIG_AUDITSYSCALL
-cstar_auditsys:
-	movl %r9d,R9(%rsp)	/* register to be clobbered by call */
-	auditsys_entry_common
-	movl R9(%rsp),%r9d	/* reload 6th syscall arg */
-	jmp cstar_dispatch
-
-sysretl_audit:
-	auditsys_exit sysretl_from_sys_call
-#endif
-
-cstar_tracesys:
-#ifdef CONFIG_AUDITSYSCALL
-	testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT), ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jz cstar_auditsys
-#endif
-	xchgl %r9d,%ebp
-	SAVE_EXTRA_REGS
-	CLEAR_RREGS r9
-	movq %rsp,%rdi        /* &pt_regs -> arg1 */
-	call syscall_trace_enter
-	LOAD_ARGS32 1	/* reload args from stack in case ptrace changed it */
-	RESTORE_EXTRA_REGS
-	xchgl %ebp,%r9d
-	jmp cstar_do_call
-END(ia32_cstar_target)
-				
-ia32_badarg:
-	ASM_CLAC
-	movq $-EFAULT,%rax
-	jmp ia32_sysret
-
-/*
- * Emulated IA32 system calls via int 0x80.
- *
- * Arguments:
- * eax  system call number
- * ebx  arg1
- * ecx  arg2
- * edx  arg3
- * esi  arg4
- * edi  arg5
- * ebp  arg6	(note: not saved in the stack frame, should not be touched)
- *
- * Notes:
- * Uses the same stack frame as the x86-64 version.
- * All registers except eax must be saved (but ptrace may violate that).
- * Arguments are zero extended. For system calls that want sign extension and
- * take long arguments a wrapper is needed. Most calls can just be called
- * directly.
- * Assumes it is only called from user space and entered with interrupts off.
- */
-
-ENTRY(ia32_syscall)
-	/*
-	 * Interrupts are off on entry.
-	 * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON,
-	 * it is too small to ever cause noticeable irq latency.
-	 */
-	PARAVIRT_ADJUST_EXCEPTION_FRAME
-	SWAPGS
-	ENABLE_INTERRUPTS(CLBR_NONE)
-
-	/* Zero-extending 32-bit regs, do not remove */
-	movl	%eax,%eax
-
-	/* Construct struct pt_regs on stack (iret frame is already on stack) */
-	pushq	%rax			/* pt_regs->orig_ax */
-	pushq	%rdi			/* pt_regs->di */
-	pushq	%rsi			/* pt_regs->si */
-	pushq	%rdx			/* pt_regs->dx */
-	pushq	%rcx			/* pt_regs->cx */
-	pushq	$-ENOSYS		/* pt_regs->ax */
-	cld
-	sub	$(10*8),%rsp /* pt_regs->r8-11,bp,bx,r12-15 not saved */
-
-	orl $TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS)
-	testl $_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
-	jnz ia32_tracesys
-ia32_do_call:
-	/* 32bit syscall -> 64bit C ABI argument conversion */
-	movl %edi,%r8d	/* arg5 */
-	movl %ebp,%r9d	/* arg6 */
-	xchg %ecx,%esi	/* rsi:arg2, rcx:arg4 */
-	movl %ebx,%edi	/* arg1 */
-	movl %edx,%edx	/* arg3 (zero extension) */
-	cmpq	$(IA32_NR_syscalls-1),%rax
-	ja	1f
-	call *ia32_sys_call_table(,%rax,8) # xxx: rip relative
-ia32_sysret:
-	movq %rax,RAX(%rsp)
-1:
-ia32_ret_from_sys_call:
-	CLEAR_RREGS
-	jmp int_ret_from_sys_call
-
-ia32_tracesys:
-	SAVE_EXTRA_REGS
-	CLEAR_RREGS
-	movq %rsp,%rdi        /* &pt_regs -> arg1 */
-	call syscall_trace_enter
-	LOAD_ARGS32	/* reload args from stack in case ptrace changed it */
-	RESTORE_EXTRA_REGS
-	jmp ia32_do_call
-END(ia32_syscall)
-
-	.macro PTREGSCALL label, func
-	ALIGN
-GLOBAL(\label)
-	leaq \func(%rip),%rax
-	jmp  ia32_ptregs_common	
-	.endm
-
-	PTREGSCALL stub32_rt_sigreturn, sys32_rt_sigreturn
-	PTREGSCALL stub32_sigreturn, sys32_sigreturn
-	PTREGSCALL stub32_fork, sys_fork
-	PTREGSCALL stub32_vfork, sys_vfork
-
-	ALIGN
-GLOBAL(stub32_clone)
-	leaq sys_clone(%rip),%rax
-	mov	%r8, %rcx
-	jmp  ia32_ptregs_common	
-
-	ALIGN
-ia32_ptregs_common:
-	SAVE_EXTRA_REGS 8
-	call *%rax
-	RESTORE_EXTRA_REGS 8
-	ret
-END(ia32_ptregs_common)