X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/5d5c5d0d5b79ade9a973d55186ffda2638ba2b6e..7ddcb079202367355dddccdfa4318e57d50318be:/osfmk/i386/idt.s diff --git a/osfmk/i386/idt.s b/osfmk/i386/idt.s index 8897897a6..362b783a4 100644 --- a/osfmk/i386/idt.s +++ b/osfmk/i386/idt.s @@ -1,31 +1,29 @@ /* - * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2000-2010 Apple Inc. All rights reserved. * - * @APPLE_LICENSE_OSREFERENCE_HEADER_START@ + * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * - * This file contains Original Code and/or Modifications of Original Code - * as defined in and that are subject to the Apple Public Source License - * Version 2.0 (the 'License'). You may not use this file except in - * compliance with the License. The rights granted to you under the - * License may not be used to create, or enable the creation or - * redistribution of, unlawful or unlicensed copies of an Apple operating - * system, or to circumvent, violate, or enable the circumvention or - * violation of, any terms of an Apple operating system software license - * agreement. - * - * Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this - * file. - * - * The Original Code and all software distributed under the License are - * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER - * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, - * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. - * Please see the License for the specific language governing rights and + * This file contains Original Code and/or Modifications of Original Code + * as defined in and that are subject to the Apple Public Source License + * Version 2.0 (the 'License'). You may not use this file except in + * compliance with the License. The rights granted to you under the License + * may not be used to create, or enable the creation or redistribution of, + * unlawful or unlicensed copies of an Apple operating system, or to + * circumvent, violate, or enable the circumvention or violation of, any + * terms of an Apple operating system software license agreement. + * + * Please obtain a copy of the License at + * http://www.opensource.apple.com/apsl/ and read it before using this file. + * + * The Original Code and all software distributed under the License are + * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER + * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, + * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. + * Please see the License for the specific language governing rights and * limitations under the License. - * - * @APPLE_LICENSE_OSREFERENCE_HEADER_END@ + * + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * @OSF_COPYRIGHT@ @@ -62,6 +60,24 @@ #include #include #include +#include +#define _ARCH_I386_ASM_HELP_H_ /* Prevent inclusion of user header */ +#include +#include +#include +#include + +/* + * Low-memory handlers. + */ +#define LO_ALLINTRS EXT(lo_allintrs32) +#define LO_ALLTRAPS EXT(lo_alltraps32) +#define LO_SYSENTER EXT(lo_sysenter32) +#define LO_UNIX_SCALL EXT(lo_unix_scall32) +#define LO_MACH_SCALL EXT(lo_mach_scall32) +#define LO_MDEP_SCALL EXT(lo_mdep_scall32) +#define LO_DIAG_SCALL EXT(lo_diag_scall32) + #define HI_DATA(lo_addr) ( (EXT(lo_addr) - EXT(hi_remap_data)) + HIGH_IDT_BASE ) #define HI_TEXT(lo_text) ( (EXT(lo_text) - EXT(hi_remap_text)) + HIGH_MEM_BASE ) @@ -71,7 +87,7 @@ */ #define IDT_BASE_ENTRY(vec,seg,type) \ .data ;\ - .long EXT(vec) - EXT(hi_remap_text) + HIGH_MEM_BASE ;\ + .long EXT(vec) - EXT(hi_remap_text) + HIGH_MEM_BASE ; \ .word seg ;\ .byte 0 ;\ .byte type ;\ @@ -79,7 +95,7 @@ #define IDT_BASE_ENTRY_INT(vec,seg,type) \ .data ;\ - .long vec - EXT(hi_remap_text) + HIGH_MEM_BASE ;\ + .long vec - EXT(hi_remap_text) + HIGH_MEM_BASE ; \ .word seg ;\ .byte 0 ;\ .byte type ;\ @@ -87,14 +103,14 @@ #define IDT_BASE_ENTRY_TG(vec,seg,type) \ .data ;\ - .long 0 ;\ + .long 0 ; \ .word seg ;\ .byte 0 ;\ .byte type ;\ .text -#define IDT_ENTRY(vec,type) IDT_BASE_ENTRY(vec,KERNEL_CS,type) -#define IDT_ENTRY_INT(vec,type) IDT_BASE_ENTRY_INT(vec,KERNEL_CS,type) +#define IDT_ENTRY(vec,type) IDT_BASE_ENTRY(vec,KERNEL32_CS,type) +#define IDT_ENTRY_INT(vec,type) IDT_BASE_ENTRY_INT(vec,KERNEL32_CS,type) /* * No error code. Clear error code and push trap number. @@ -105,7 +121,7 @@ Entry(name) ;\ pushl $0 ;\ pushl $(n) ;\ pusha ;\ - movl $ EXT(lo_alltraps),%ebx ;\ + movl $(LO_ALLTRAPS),%ebx ;\ jmp enter_lohandler @@ -118,7 +134,7 @@ Entry(name) ;\ pushl $0 ;\ pushl $(n) ;\ pusha ;\ - movl $ EXT(lo_alltraps),%ebx ;\ + movl $(LO_ALLTRAPS),%ebx ;\ jmp enter_lohandler @@ -154,11 +170,11 @@ Entry(name) ;\ * Error code has been pushed. Push trap number. */ #define EXCEP_ERR(n,name) \ - IDT_ENTRY(name,K_INTR_GATE);\ -Entry(name) ;\ - pushl $(n) ;\ - pusha ;\ - movl $ EXT(lo_alltraps),%ebx ;\ + IDT_ENTRY(name,K_INTR_GATE) ;\ +Entry(name) ;\ + pushl $(n) ;\ + pusha ;\ + movl $(LO_ALLTRAPS),%ebx ;\ jmp enter_lohandler @@ -172,7 +188,7 @@ L_ ## n: ;\ pushl $0 ;\ pushl $(n) ;\ pusha ;\ - movl $ EXT(lo_allintrs),%ebx ;\ + movl $(LO_ALLINTRS),%ebx ;\ jmp enter_lohandler @@ -181,6 +197,7 @@ L_ ## n: ;\ Entry(master_idt) Entry(hi_remap_data) .text + .align 12 Entry(hi_remap_text) EXCEPTION(0x00,t_zero_div) @@ -324,7 +341,7 @@ INTERRUPT(0x7b) INTERRUPT(0x7c) INTERRUPT(0x7d) INTERRUPT(0x7e) -INTERRUPT(0x7f) +EXCEP_USR(0x7f, t_dtrace_ret) EXCEP_SPC_USR(0x80,hi_unix_scall) EXCEP_SPC_USR(0x81,hi_mach_scall) @@ -472,8 +489,7 @@ Entry(lo_kernel_cr3) .text -/******************************************************************************************************* - * +/* * Trap/interrupt entry points. * * All traps must create the following save area on the PCB "stack": @@ -499,14 +515,21 @@ Entry(lo_kernel_cr3) * user ss - if from user */ - +ret_to_kernel: + jmp *1f +1: .long HI_TEXT(hi_ret_to_kernel) + +ret_to_user: + jmp *1f +1: .long HI_TEXT(hi_ret_to_user) + Entry(hi_ret_to_user) movl %esp,%ebx movl %gs:CPU_ACTIVE_THREAD,%ecx - subl ACT_PCB_ISS(%ecx),%ebx - movl $(WINDOWS_CLEAN),ACT_COPYIO_STATE(%ecx) + subl TH_PCB_ISS(%ecx),%ebx + movl $(WINDOWS_CLEAN),TH_COPYIO_STATE(%ecx) - movl ACT_PCB_IDS(%ecx),%eax /* get debug state struct */ + movl TH_PCB_IDS(%ecx),%eax /* get debug state struct */ cmpl $0,%eax /* is there a debug state */ je 1f /* branch if not */ movl DS_DR0(%eax), %ecx /* Load the 32 bit debug registers */ @@ -550,22 +573,20 @@ EXT(ret_popl_ds): EXT(ret_iret): iret /* return from interrupt */ fast_exit: - popl %edx /* user return eip */ - popl %ecx /* pop and toss cs */ + popl %edx /* user return eip */ + popl %ecx /* pop and toss cs */ andl $(~EFL_IF),(%esp) /* clear intrs enabled, see sti below */ - popf /* flags - carry denotes failure */ - popl %ecx /* user return esp */ + popf /* flags - carry denotes failure */ + popl %ecx /* user return esp */ sti /* interrupts enabled after sysexit */ - sysexit - -/*******************************************************************************************************/ + sysexit Entry(hi_unix_scall) pushl %eax /* save system call number */ pushl $0 /* clear trap number slot */ pusha /* save the general registers */ - movl $ EXT(lo_unix_scall),%ebx + movl $(LO_UNIX_SCALL),%ebx jmp enter_lohandler @@ -573,7 +594,7 @@ Entry(hi_mach_scall) pushl %eax /* save system call number */ pushl $0 /* clear trap number slot */ pusha /* save the general registers */ - movl $ EXT(lo_mach_scall),%ebx + movl $(LO_MACH_SCALL),%ebx jmp enter_lohandler @@ -581,7 +602,7 @@ Entry(hi_mdep_scall) pushl %eax /* save system call number */ pushl $0 /* clear trap number slot */ pusha /* save the general registers */ - movl $ EXT(lo_mdep_scall),%ebx + movl $(LO_MDEP_SCALL),%ebx jmp enter_lohandler @@ -589,7 +610,7 @@ Entry(hi_diag_scall) pushl %eax // Save sselector pushl $0 // Clear trap number slot pusha // save the general registers - movl $EXT(lo_diag_scall),%ebx // Get the function down low to transfer to + movl $(LO_DIAG_SCALL),%ebx // Get the function down low to transfer to jmp enter_lohandler // Leap to it... @@ -614,10 +635,9 @@ Entry(hi_sysenter) pushf /* flags */ /* * Clear, among others, the Nested Task (NT) flags bit; - * This is cleared by INT, but not by sysenter, which only - * clears RF, VM and IF. + * This is cleared by INT, but not by SYSENTER. */ - pushl $0 + pushl $0 popfl pushl $(SYSENTER_CS) /* cs */ hi_sysenter_2: @@ -625,15 +645,15 @@ hi_sysenter_2: pushl %eax /* err/eax - syscall code */ pushl $0 /* clear trap number slot */ pusha /* save the general registers */ - orl $(EFL_IF),R_EFLAGS-R_EDI(%esp) /* (edi was last reg pushed) */ - movl $ EXT(lo_sysenter),%ebx + orl $(EFL_IF),R32_EFLAGS-R32_EDI(%esp) /* (edi was last reg pushed) */ + movl $(LO_SYSENTER),%ebx enter_lohandler: pushl %ds pushl %es pushl %fs pushl %gs -enter_lohandler1: pushl $(SS_32) /* 32-bit state flavor */ +enter_lohandler1: mov %ss,%eax mov %eax,%ds mov %eax,%fs @@ -651,21 +671,22 @@ enter_lohandler1: movl %ecx,%cr3 movl %ecx,%gs:CPU_ACTIVE_CR3 1: - testb $3,R_CS(%esp) + testb $3,R32_CS(%esp) jz 2f movl %esp,%edx /* came from user mode */ + xor %ebp, %ebp subl %gs:CPU_HI_ISS,%edx movl %gs:CPU_ACTIVE_THREAD,%ecx - addl ACT_PCB_ISS(%ecx),%edx /* rebase the high stack to a low address */ + addl TH_PCB_ISS(%ecx),%edx /* rebase the high stack to a low address */ movl %edx,%esp - cmpl $0, ACT_PCB_IDS(%ecx) /* Is there a debug register state? */ + cmpl $0, TH_PCB_IDS(%ecx) /* Is there a debug register state? */ je 2f movl $0, %ecx /* If so, reset DR7 (the control) */ movl %ecx, %dr7 2: - movl R_TRAPNO(%esp),%ecx // Get the interrupt vector + movl R32_TRAPNO(%esp),%ecx // Get the interrupt vector addl $1,%gs:hwIntCnt(,%ecx,4) // Bump the count - jmp *%ebx + jmp *%ebx /* @@ -675,9 +696,9 @@ Entry(hi_page_fault) pushl $(T_PAGE_FAULT) /* mark a page fault trap */ pusha /* save the general registers */ movl %cr2,%eax /* get the faulting address */ - movl %eax,R_CR2-R_EDI(%esp) /* save in esp save slot */ + movl %eax,R32_CR2-R32_EDI(%esp)/* save in esp save slot */ - movl $ EXT(lo_alltraps),%ebx + movl $(LO_ALLTRAPS),%ebx jmp enter_lohandler @@ -732,7 +753,7 @@ hi_debug_trap: pushl $0 pushl $(T_DEBUG) /* handle as user trap */ pusha /* save the general registers */ - movl $ EXT(lo_alltraps),%ebx + movl $(LO_ALLTRAPS),%ebx jmp enter_lohandler @@ -773,7 +794,7 @@ trap_check_kernel_exit: je fault_popl_gs hi_take_trap: pusha /* save the general registers */ - movl $ EXT(lo_alltraps),%ebx + movl $(LO_ALLTRAPS),%ebx jmp enter_lohandler @@ -802,7 +823,7 @@ fault_iret: popl %eax /* restore eax */ /* now treat as fault from user */ pusha /* save the general registers */ - movl $ EXT(lo_alltraps),%ebx + movl $(LO_ALLTRAPS),%ebx jmp enter_lohandler /* @@ -838,24 +859,477 @@ push_fs: push_gs: pushl %gs /* restore gs. */ push_none: - movl %eax,R_TRAPNO(%esp) /* set trap number */ - movl %edx,R_ERR(%esp) /* set error code */ + pushl $(SS_32) /* 32-bit state flavor */ + movl %eax,R32_TRAPNO(%esp) /* set trap number */ + movl %edx,R32_ERR(%esp) /* set error code */ /* now treat as fault from user */ /* except that segment registers are */ /* already pushed */ - movl $ EXT(lo_alltraps),%ebx + movl $(LO_ALLTRAPS),%ebx jmp enter_lohandler1 .text -Entry(lo_ret_to_user) - jmp *1f -1: .long HI_TEXT(hi_ret_to_user) +Entry(hi_remap_etext) -Entry(lo_ret_to_kernel) - jmp *1f -1: .long HI_TEXT(hi_ret_to_kernel) -Entry(hi_remap_etext) +/* + * All 32 bit task 'exceptions' enter lo_alltraps: + * esp -> x86_saved_state_t + * + * The rest of the state is set up as: + * cr3 -> kernel directory + * esp -> low based stack + * gs -> CPU_DATA_GS + * cs -> KERNEL32_CS + * ss/ds/es -> KERNEL_DS + * + * interrupts disabled + * direction flag cleared + */ +Entry(lo_alltraps32) + movl R32_CS(%esp),%eax /* assume 32-bit state */ + cmpl $(SS_64),SS_FLAVOR(%esp)/* 64-bit? */ + jne 1f + movl R64_CS(%esp),%eax /* 64-bit user mode */ +1: + testb $3,%al + jz trap_from_kernel + /* user mode trap */ + TIME_TRAP_UENTRY + + movl %gs:CPU_ACTIVE_THREAD,%ecx + movl TH_TASK(%ecx),%ebx + + /* Check for active vtimers in the current task */ + TASK_VTIMER_CHECK(%ebx, %ecx) + + movl %gs:CPU_KERNEL_STACK,%ebx + xchgl %ebx,%esp /* switch to kernel stack */ + + CCALL1(user_trap, %ebx) /* call user trap routine */ + /* user_trap() unmasks interrupts */ + cli /* hold off intrs - critical section */ + xorl %ecx,%ecx /* don't check if we're in the PFZ */ + +/* + * Return from trap or system call, checking for ASTs. + * On lowbase PCB stack with intrs disabled + */ +Entry(return_from_trap32) + movl %gs:CPU_ACTIVE_THREAD, %esp + movl TH_PCB_ISS(%esp), %esp /* switch back to PCB stack */ + movl %gs:CPU_PENDING_AST, %eax + testl %eax, %eax + je EXT(return_to_user) /* branch if no AST */ +LEXT(return_from_trap_with_ast) + movl %gs:CPU_KERNEL_STACK, %ebx + xchgl %ebx, %esp /* switch to kernel stack */ + + testl %ecx, %ecx /* see if we need to check for an EIP in the PFZ */ + je 2f /* no, go handle the AST */ + cmpl $(SS_64), SS_FLAVOR(%ebx) /* are we a 64-bit task? */ + je 1f + /* no... 32-bit user mode */ + movl R32_EIP(%ebx), %eax + pushl %ebx /* save PCB stack */ + xorl %ebp, %ebp /* clear frame pointer */ + CCALL1(commpage_is_in_pfz32, %eax) + popl %ebx /* retrieve pointer to PCB stack */ + testl %eax, %eax + je 2f /* not in the PFZ... go service AST */ + movl %eax, R32_EBX(%ebx) /* let the PFZ know we've pended an AST */ + xchgl %ebx, %esp /* switch back to PCB stack */ + jmp EXT(return_to_user) +1: /* 64-bit user mode */ + movl R64_RIP(%ebx), %ecx + movl R64_RIP+4(%ebx), %eax + pushl %ebx /* save PCB stack */ + xorl %ebp, %ebp /* clear frame pointer */ + CCALL2(commpage_is_in_pfz64, %ecx, %eax) + popl %ebx /* retrieve pointer to PCB stack */ + testl %eax, %eax + je 2f /* not in the PFZ... go service AST */ + movl %eax, R64_RBX(%ebx) /* let the PFZ know we've pended an AST */ + xchgl %ebx, %esp /* switch back to PCB stack */ + jmp EXT(return_to_user) +2: + sti /* interrupts always enabled on return to user mode */ + xorl %ebp, %ebp /* Clear framepointer */ + CCALL1(i386_astintr, $0) /* take the AST */ + cli + xorl %ecx, %ecx /* don't check if we're in the PFZ */ + jmp EXT(return_from_trap32) /* and check again (rare) */ + + +/* + * Trap from kernel mode. No need to switch stacks. + * Interrupts must be off here - we will set them to state at time of trap + * as soon as it's safe for us to do so and not recurse doing preemption + */ +trap_from_kernel: + movl %esp, %eax /* saved state addr */ + pushl R32_EIP(%esp) /* Simulate a CALL from fault point */ + pushl %ebp /* Extend framepointer chain */ + movl %esp, %ebp + CCALL1WITHSP(kernel_trap, %eax) /* Call kernel trap handler */ + popl %ebp + addl $4, %esp + cli + + movl %gs:CPU_PENDING_AST,%eax /* get pending asts */ + testl $ AST_URGENT,%eax /* any urgent preemption? */ + je ret_to_kernel /* no, nothing to do */ + cmpl $ T_PREEMPT,R32_TRAPNO(%esp) + je ret_to_kernel /* T_PREEMPT handled in kernel_trap() */ + testl $ EFL_IF,R32_EFLAGS(%esp) /* interrupts disabled? */ + je ret_to_kernel + cmpl $0,%gs:CPU_PREEMPTION_LEVEL /* preemption disabled? */ + jne ret_to_kernel + movl %gs:CPU_KERNEL_STACK,%eax + movl %esp,%ecx + xorl %eax,%ecx + and EXT(kernel_stack_mask),%ecx + testl %ecx,%ecx /* are we on the kernel stack? */ + jne ret_to_kernel /* no, skip it */ + + CCALL1(i386_astintr, $1) /* take the AST */ + + jmp ret_to_kernel + + +/* + * All interrupts on all tasks enter here with: + * esp-> -> x86_saved_state_t + * + * cr3 -> kernel directory + * esp -> low based stack + * gs -> CPU_DATA_GS + * cs -> KERNEL32_CS + * ss/ds/es -> KERNEL_DS + * + * interrupts disabled + * direction flag cleared + */ +Entry(lo_allintrs32) + /* + * test whether already on interrupt stack + */ + movl %gs:CPU_INT_STACK_TOP,%ecx + cmpl %esp,%ecx + jb 1f + leal -INTSTACK_SIZE(%ecx),%edx + cmpl %esp,%edx + jb int_from_intstack +1: + xchgl %ecx,%esp /* switch to interrupt stack */ + + movl %cr0,%eax /* get cr0 */ + orl $(CR0_TS),%eax /* or in TS bit */ + movl %eax,%cr0 /* set cr0 */ + + subl $8, %esp /* for 16-byte stack alignment */ + pushl %ecx /* save pointer to old stack */ + movl %ecx,%gs:CPU_INT_STATE /* save intr state */ + + TIME_INT_ENTRY /* do timing */ + + movl %gs:CPU_ACTIVE_THREAD,%ecx + movl TH_TASK(%ecx),%ebx + + /* Check for active vtimers in the current task */ + TASK_VTIMER_CHECK(%ebx, %ecx) + + incl %gs:CPU_PREEMPTION_LEVEL + incl %gs:CPU_INTERRUPT_LEVEL + + movl %gs:CPU_INT_STATE, %eax + CCALL1(interrupt, %eax) /* call generic interrupt routine */ + + cli /* just in case we returned with intrs enabled */ + xorl %eax,%eax + movl %eax,%gs:CPU_INT_STATE /* clear intr state pointer */ + + decl %gs:CPU_INTERRUPT_LEVEL + decl %gs:CPU_PREEMPTION_LEVEL + + TIME_INT_EXIT /* do timing */ + + movl %gs:CPU_ACTIVE_THREAD,%eax + movl TH_PCB_FPS(%eax),%eax /* get pcb's ifps */ + testl %eax, %eax /* Is there a context */ + je 1f /* Branch if not */ + cmpl $0, FP_VALID(%eax) /* Check fp_valid */ + jne 1f /* Branch if valid */ + clts /* Clear TS */ + jmp 2f +1: + movl %cr0,%eax /* get cr0 */ + orl $(CR0_TS),%eax /* or in TS bit */ + movl %eax,%cr0 /* set cr0 */ +2: + popl %esp /* switch back to old stack */ + + /* Load interrupted code segment into %eax */ + movl R32_CS(%esp),%eax /* assume 32-bit state */ + cmpl $(SS_64),SS_FLAVOR(%esp)/* 64-bit? */ + jne 3f + movl R64_CS(%esp),%eax /* 64-bit user mode */ +3: + testb $3,%al /* user mode, */ + jnz ast_from_interrupt_user /* go handle potential ASTs */ + /* + * we only want to handle preemption requests if + * the interrupt fell in the kernel context + * and preemption isn't disabled + */ + movl %gs:CPU_PENDING_AST,%eax + testl $ AST_URGENT,%eax /* any urgent requests? */ + je ret_to_kernel /* no, nothing to do */ + + cmpl $0,%gs:CPU_PREEMPTION_LEVEL /* preemption disabled? */ + jne ret_to_kernel /* yes, skip it */ + + movl %gs:CPU_KERNEL_STACK,%eax + movl %esp,%ecx + xorl %eax,%ecx + and EXT(kernel_stack_mask),%ecx + testl %ecx,%ecx /* are we on the kernel stack? */ + jne ret_to_kernel /* no, skip it */ + + /* + * Take an AST from kernel space. We don't need (and don't want) + * to do as much as the case where the interrupt came from user + * space. + */ + CCALL1(i386_astintr, $1) + + jmp ret_to_kernel + + +/* + * nested int - simple path, can't preempt etc on way out + */ +int_from_intstack: + incl %gs:CPU_PREEMPTION_LEVEL + incl %gs:CPU_INTERRUPT_LEVEL + + movl %esp, %edx /* x86_saved_state */ + CCALL1(interrupt, %edx) + + decl %gs:CPU_INTERRUPT_LEVEL + decl %gs:CPU_PREEMPTION_LEVEL + + jmp ret_to_kernel + +/* + * Take an AST from an interrupted user + */ +ast_from_interrupt_user: + movl %gs:CPU_PENDING_AST,%eax + testl %eax,%eax /* pending ASTs? */ + je ret_to_user /* no, nothing to do */ + + TIME_TRAP_UENTRY + + movl $1, %ecx /* check if we're in the PFZ */ + jmp EXT(return_from_trap_with_ast) /* return */ + + +/* + * 32bit Tasks + * System call entries via INTR_GATE or sysenter: + * + * esp -> x86_saved_state32_t + * cr3 -> kernel directory + * esp -> low based stack + * gs -> CPU_DATA_GS + * cs -> KERNEL32_CS + * ss/ds/es -> KERNEL_DS + * + * interrupts disabled + * direction flag cleared + */ + +Entry(lo_sysenter32) + /* + * We can be here either for a mach syscall or a unix syscall, + * as indicated by the sign of the code: + */ + movl R32_EAX(%esp),%eax + testl %eax,%eax + js EXT(lo_mach_scall32) /* < 0 => mach */ + /* > 0 => unix */ + +Entry(lo_unix_scall32) + TIME_TRAP_UENTRY + + movl %gs:CPU_KERNEL_STACK,%edi + xchgl %edi,%esp /* switch to kernel stack */ + movl %gs:CPU_ACTIVE_THREAD,%ecx /* get current thread */ + movl TH_TASK(%ecx),%ebx /* point to current task */ + incl TH_SYSCALLS_UNIX(%ecx) /* increment call count */ + + /* Check for active vtimers in the current task */ + TASK_VTIMER_CHECK(%ebx, %ecx) + + sti + + CCALL1(unix_syscall, %edi) + /* + * always returns through thread_exception_return + */ + + +Entry(lo_mach_scall32) + TIME_TRAP_UENTRY + + movl %gs:CPU_KERNEL_STACK,%edi + xchgl %edi,%esp /* switch to kernel stack */ + movl %gs:CPU_ACTIVE_THREAD,%ecx /* get current thread */ + movl TH_TASK(%ecx),%ebx /* point to current task */ + incl TH_SYSCALLS_MACH(%ecx) /* increment call count */ + + /* Check for active vtimers in the current task */ + TASK_VTIMER_CHECK(%ebx, %ecx) + + sti + + CCALL1(mach_call_munger, %edi) + /* + * always returns through thread_exception_return + */ + + +Entry(lo_mdep_scall32) + TIME_TRAP_UENTRY + + movl %gs:CPU_KERNEL_STACK,%edi + xchgl %edi,%esp /* switch to kernel stack */ + movl %gs:CPU_ACTIVE_THREAD,%ecx /* get current thread */ + movl TH_TASK(%ecx),%ebx /* point to current task */ + + /* Check for active vtimers in the current task */ + TASK_VTIMER_CHECK(%ebx, %ecx) + + sti + + CCALL1(machdep_syscall, %edi) + /* + * always returns through thread_exception_return + */ + + +Entry(lo_diag_scall32) + TIME_TRAP_UENTRY + + movl %gs:CPU_KERNEL_STACK,%edi + xchgl %edi,%esp /* switch to kernel stack */ + movl %gs:CPU_ACTIVE_THREAD,%ecx /* get current thread */ + movl TH_TASK(%ecx),%ebx /* point to current task */ + + /* Check for active vtimers in the current task */ + TASK_VTIMER_CHECK(%ebx, %ecx) + + pushl %edi /* push pbc stack for later */ + + CCALL1(diagCall, %edi) // Call diagnostics + + cli // Disable interruptions just in case + popl %esp // Get back the original stack + cmpl $0,%eax // What kind of return is this? + jne EXT(return_to_user) // Normal return, do not check asts... + + CCALL5(i386_exception, $EXC_SYSCALL, $0x6000, $0, $1, $0) + // pass what would be the diag syscall + // error return - cause an exception + /* no return */ + + +LEXT(return_to_user) + TIME_TRAP_UEXIT + jmp ret_to_user + + +/* + * Double-fault exception handler task. The last gasp... + */ +Entry(df_task_start) + CCALL1(panic_double_fault32, $(T_DOUBLE_FAULT)) + hlt + + +/* + * machine-check handler task. The last gasp... + */ +Entry(mc_task_start) + CCALL1(panic_machine_check32, $(T_MACHINE_CHECK)) + hlt + +#if MACH_KDB +#include +#define CX(addr,reg) addr(,reg,4) +#if 0 +/* + * Note that the per-fault entry points are not currently + * functional. The only way to make them work would be to + * set up separate TSS's for each fault type, which doesn't + * currently seem worthwhile. (The offset part of a task + * gate is always ignored.) So all faults that task switch + * currently resume at db_task_start. + */ +/* + * Double fault (Murphy's point) - error code (0) on stack + */ +Entry(db_task_dbl_fault) + popl %eax + movl $(T_DOUBLE_FAULT),%ebx + jmp db_task_start +/* + * Segment not present - error code on stack + */ +Entry(db_task_seg_np) + popl %eax + movl $(T_SEGMENT_NOT_PRESENT),%ebx + jmp db_task_start +/* + * Stack fault - error code on (current) stack + */ +Entry(db_task_stk_fault) + popl %eax + movl $(T_STACK_FAULT),%ebx + jmp db_task_start +/* + * General protection fault - error code on stack + */ +Entry(db_task_gen_prot) + popl %eax + movl $(T_GENERAL_PROTECTION),%ebx + jmp db_task_start +#endif /* 0 */ +/* + * The entry point where execution resumes after last-ditch debugger task + * switch. + */ +Entry(db_task_start) + movl %esp,%edx + subl $(ISS32_SIZE),%edx + movl %edx,%esp /* allocate x86_saved_state on stack */ + movl %eax,R32_ERR(%esp) + movl %ebx,R32_TRAPNO(%esp) + pushl %edx + CPU_NUMBER(%edx) + movl CX(EXT(master_dbtss),%edx),%edx + movl TSS_LINK(%edx),%eax + pushl %eax /* pass along selector of previous TSS */ + call EXT(db_tss_to_frame) + popl %eax /* get rid of TSS selector */ + call EXT(db_trap_from_asm) + addl $0x4,%esp + /* + * And now...? + */ + iret /* ha, ha, ha... */ +#endif /* MACH_KDB */