diff options
Diffstat (limited to 'arch/x86/ia32/ia32entry.S')
| -rw-r--r-- | arch/x86/ia32/ia32entry.S | 522 |
1 files changed, 0 insertions, 522 deletions
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) |