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authorIngo Molnar <mingo@kernel.org>2015-06-03 19:00:59 +0300
committerIngo Molnar <mingo@kernel.org>2015-06-03 19:51:32 +0300
commit19a433f45135656d065bdf1bbe543796b194ba3a (patch)
treedccbde4ce9cc48d54ca9d1760de613789df6d195 /arch/x86/ia32
parent905a36a2851838bca5a424fb758e201990234e6e (diff)
downloadlinux-19a433f45135656d065bdf1bbe543796b194ba3a.tar.xz
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>
Diffstat (limited to 'arch/x86/ia32')
-rw-r--r--arch/x86/ia32/Makefile2
-rw-r--r--arch/x86/ia32/ia32entry.S522
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)