Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files. =================================================================== RCS file: /ftp/cvs/cvsroot/src/sys/arch/i386/i386/locore.S,v rcsdiff: /ftp/cvs/cvsroot/src/sys/arch/i386/i386/locore.S,v: warning: Unknown phrases like `commitid ...;' are present. retrieving revision 1.29 retrieving revision 1.45.2.3 diff -u -p -r1.29 -r1.45.2.3 --- src/sys/arch/i386/i386/locore.S 2004/08/05 15:25:29 1.29 +++ src/sys/arch/i386/i386/locore.S 2007/02/27 16:51:38 1.45.2.3 @@ -1,7 +1,7 @@ -/* $NetBSD: locore.S,v 1.29 2004/08/05 15:25:29 mycroft Exp $ */ +/* $NetBSD: locore.S,v 1.45.2.3 2007/02/27 16:51:38 yamt Exp $ */ /*- - * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc. + * Copyright (c) 1998, 2000, 2004 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation @@ -83,7 +83,6 @@ #include "npx.h" #include "assym.h" -#include "apm.h" #include "lapic.h" #include "ioapic.h" #include "ksyms.h" @@ -92,42 +91,22 @@ #include #include -#include -#include #include #include #include -#include #if NLAPIC > 0 #include #endif +#include + /* LINTSTUB: include */ /* LINTSTUB: include */ /* LINTSTUB: include */ #include -#if defined(MULTIPROCESSOR) - -#define SET_CURLWP(lwp,cpu) \ - movl CPUVAR(SELF),cpu ; \ - movl lwp,CPUVAR(CURLWP) ; \ - movl cpu,L_CPU(lwp) - -#else - -#define SET_CURLWP(lwp,tcpu) movl lwp,CPUVAR(CURLWP) -#define GET_CURLWP(reg) movl CPUVAR(CURLWP),reg - -#endif - -#define GET_CURPCB(reg) movl CPUVAR(CURPCB),reg -#define SET_CURPCB(reg) movl reg,CPUVAR(CURPCB) - -#define CLEAR_RESCHED(reg) movl reg,CPUVAR(RESCHED) - /* XXX temporary kluge; these should not be here */ /* Get definitions for IOM_BEGIN, IOM_END, and IOM_SIZE */ #include @@ -152,27 +131,6 @@ #ifdef MULTIPROCESSOR #include #endif - -/* - * PTmap is recursive pagemap at top of virtual address space. - * Within PTmap, the page directory can be found (third indirection). - * - * XXX 4 == sizeof pde - */ - .set _C_LABEL(PTmap),(PDSLOT_PTE << PDSHIFT) - .set _C_LABEL(PTD),(_C_LABEL(PTmap) + PDSLOT_PTE * PAGE_SIZE) - .set _C_LABEL(PTDpde),(_C_LABEL(PTD) + PDSLOT_PTE * 4) - -/* - * APTmap, APTD is the alternate recursive pagemap. - * It's used when modifying another process's page tables. - * - * XXX 4 == sizeof pde - */ - .set _C_LABEL(APTmap),(PDSLOT_APTE << PDSHIFT) - .set _C_LABEL(APTD),(_C_LABEL(APTmap) + PDSLOT_APTE * PAGE_SIZE) - .set _C_LABEL(APTDpde),(_C_LABEL(PTD) + PDSLOT_APTE * 4) - /* * Initialization @@ -180,19 +138,15 @@ .data .globl _C_LABEL(cpu) - .globl _C_LABEL(esym),_C_LABEL(boothowto) - .globl _C_LABEL(bootinfo),_C_LABEL(atdevbase) -#ifdef COMPAT_OLDBOOT - .globl _C_LABEL(bootdev) -#endif - .globl _C_LABEL(proc0paddr),_C_LABEL(PTDpaddr) - .globl _C_LABEL(biosbasemem),_C_LABEL(biosextmem) + .globl _C_LABEL(esym) + .globl _C_LABEL(atdevbase) + .globl _C_LABEL(proc0uarea),_C_LABEL(PDPpaddr) .globl _C_LABEL(gdt) #ifdef I586_CPU .globl _C_LABEL(idt) #endif - .globl _C_LABEL(lapic_tpr) - + .globl _C_LABEL(lapic_tpr) + #if NLAPIC > 0 #ifdef __ELF__ .align PAGE_SIZE @@ -202,43 +156,32 @@ .globl _C_LABEL(local_apic), _C_LABEL(lapic_id) _C_LABEL(local_apic): .space LAPIC_ID -_C_LABEL(lapic_id): +_C_LABEL(lapic_id): .long 0x00000000 .space LAPIC_TPRI-(LAPIC_ID+4) -_C_LABEL(lapic_tpr): +_C_LABEL(lapic_tpr): .space LAPIC_PPRI-LAPIC_TPRI -_C_LABEL(lapic_ppr): +_C_LABEL(lapic_ppr): .space LAPIC_ISR-LAPIC_PPRI _C_LABEL(lapic_isr): .space PAGE_SIZE-LAPIC_ISR #else -_C_LABEL(lapic_tpr): +_C_LABEL(lapic_tpr): .long 0 #endif - + _C_LABEL(cpu): .long 0 # are we 386, 386sx, or 486, # or Pentium, or.. -_C_LABEL(esym): .long 0 # ptr to end of syms _C_LABEL(atdevbase): .long 0 # location of start of iomem in virtual -_C_LABEL(proc0paddr): .long 0 -_C_LABEL(PTDpaddr): .long 0 # paddr of PTD, for libkvm -#ifndef REALBASEMEM -_C_LABEL(biosbasemem): .long 0 # base memory reported by BIOS -#else -_C_LABEL(biosbasemem): .long REALBASEMEM -#endif -#ifndef REALEXTMEM -_C_LABEL(biosextmem): .long 0 # extended memory reported by BIOS -#else -_C_LABEL(biosextmem): .long REALEXTMEM -#endif - +_C_LABEL(proc0uarea): .long 0 +_C_LABEL(PDPpaddr): .long 0 # paddr of PDP, for libkvm + .space 512 tmpstk: -#define _RELOC(x) ((x) - KERNBASE_LOCORE) +#define _RELOC(x) ((x) - KERNBASE) #define RELOC(x) _RELOC(_C_LABEL(x)) .text @@ -248,66 +191,47 @@ tmpstk: .globl start start: movw $0x1234,0x472 # warm boot - /* - * Load parameters from stack - * (howto, [bootdev], bootinfo, esym, basemem, extmem). - */ - movl 4(%esp),%eax - movl %eax,RELOC(boothowto) -#ifdef COMPAT_OLDBOOT - movl 8(%esp),%eax - movl %eax,RELOC(bootdev) -#endif - movl 12(%esp),%eax +#if defined(MULTIBOOT) + jmp 1f + + .align 4 + .globl Multiboot_Header +_C_LABEL(Multiboot_Header): +#define MULTIBOOT_HEADER_FLAGS (MULTIBOOT_HEADER_WANT_MEMORY) + .long MULTIBOOT_HEADER_MAGIC + .long MULTIBOOT_HEADER_FLAGS + .long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS) - testl %eax, %eax - jz 1f - movl (%eax), %ebx /* number of entries */ - movl $RELOC(bootinfo), %edi - movl %ebx, (%edi) - addl $4, %edi -2: - testl %ebx, %ebx - jz 1f - addl $4, %eax - movl (%eax), %ecx /* address of entry */ - pushl %eax - pushl (%ecx) /* len */ - pushl %ecx - pushl %edi - addl (%ecx), %edi /* update dest pointer */ - cmpl $_RELOC(_C_LABEL(bootinfo) + BOOTINFO_MAXSIZE), %edi - jg 2f - call _C_LABEL(memcpy) - addl $12, %esp - popl %eax - subl $1, %ebx - jmp 2b -2: /* cleanup for overflow case */ - addl $16, %esp - movl $RELOC(bootinfo), %edi - subl %ebx, (%edi) /* correct number of entries */ 1: + /* Check if we are being executed by a Multiboot-compliant boot + * loader. */ + cmpl $MULTIBOOT_INFO_MAGIC,%eax + jne 1f - movl 16(%esp),%eax - testl %eax,%eax - jz 1f - addl $KERNBASE_LOCORE,%eax -1: movl %eax,RELOC(esym) + /* + * Indeed, a multiboot-compliant boot loader executed us. We copy + * the received Multiboot information structure into kernel's data + * space to process it later -- after we are relocated. It will + * be safer to run complex C code than doing it at this point. + */ + pushl %ebx # Address of Multiboot information + call _C_LABEL(multiboot_pre_reloc) + addl $4,%esp + jmp 2f +#endif - movl RELOC(biosextmem),%eax - testl %eax,%eax - jnz 1f - movl 20(%esp),%eax - movl %eax,RELOC(biosextmem) -1: - movl RELOC(biosbasemem),%eax - testl %eax,%eax - jnz 1f - movl 24(%esp),%eax - movl %eax,RELOC(biosbasemem) 1: + /* + * At this point, we know that a NetBSD-specific boot loader + * booted this kernel. The stack carries the following parameters: + * (boothowto, [bootdev], bootinfo, esym, biosextmem, biosbasemem), + * 4 bytes each. + */ + addl $4,%esp # Discard return address to boot loader + call _C_LABEL(native_loader) + addl $24,%esp +2: /* First, reset the PSL. */ pushl $PSL_MBO popfl @@ -497,7 +421,7 @@ try586: /* Use the `cpuid' instruction. /* * Virtual address space of kernel: * - * text | data | bss | [syms] | page dir | proc0 kstack + * text | data | bss | [syms] | page dir | proc0 kstack * 0 1 2 3 */ #define PROC0PDIR ((0) * PAGE_SIZE) @@ -512,7 +436,7 @@ try586: /* Use the `cpuid' instruction. movl RELOC(esym),%eax testl %eax,%eax jz 1f - subl $KERNBASE_LOCORE,%eax + subl $KERNBASE,%eax movl %eax,%edi 1: #endif @@ -572,7 +496,7 @@ try586: /* Use the `cpuid' instruction. /* Calculate end of text segment, rounded to a page. */ leal (RELOC(etext)+PGOFSET),%edx andl $~PGOFSET,%edx - + /* Skip over the first 1MB. */ movl $_RELOC(KERNTEXTOFF),%eax movl %eax,%ecx @@ -620,8 +544,8 @@ try586: /* Use the `cpuid' instruction. leal (PROC0PDIR+PG_V|PG_KW)(%esi),%eax # pte for ptd movl %eax,(PROC0PDIR+PDSLOT_PTE*4)(%esi) # recursive PD slot - /* Save phys. addr of PTD, for libkvm. */ - movl %esi,RELOC(PTDpaddr) + /* Save phys. addr of PDP, for libkvm. */ + movl %esi,RELOC(PDPpaddr) /* Load base of page directory and enable mapping. */ movl %esi,%eax # phys address of ptd in proc 0 @@ -635,10 +559,10 @@ try586: /* Use the `cpuid' instruction. ret begin: - /* Now running relocated at KERNBASE_LOCORE. Remove double mapping. */ + /* Now running relocated at KERNBASE. Remove double mapping. */ movl _C_LABEL(nkpde),%ecx # for this many pde s, leal (PROC0PDIR+0*4)(%esi),%ebx # which is where temp maps! - addl $(KERNBASE_LOCORE), %ebx # now use relocated address + addl $(KERNBASE), %ebx # now use relocated address 1: movl $0,(%ebx) addl $4,%ebx # next pde loop 1b @@ -646,22 +570,30 @@ begin: /* Relocate atdevbase. */ movl _C_LABEL(nkpde),%edx shll $PGSHIFT,%edx - addl $(TABLESIZE+KERNBASE_LOCORE),%edx + addl $(TABLESIZE+KERNBASE),%edx addl %esi,%edx movl %edx,_C_LABEL(atdevbase) /* Set up bootstrap stack. */ - leal (PROC0STACK+KERNBASE_LOCORE)(%esi),%eax - movl %eax,_C_LABEL(proc0paddr) - leal (USPACE-FRAMESIZE)(%eax),%esp - movl %esi,PCB_CR3(%eax) # pcb->pcb_cr3 + leal (PROC0STACK+KERNBASE)(%esi),%eax + movl %eax,_C_LABEL(proc0uarea) + leal (KSTACK_SIZE-FRAMESIZE)(%eax),%esp + movl %esi,(KSTACK_SIZE+PCB_CR3)(%eax) # pcb->pcb_cr3 xorl %ebp,%ebp # mark end of frames +#if defined(MULTIBOOT) + /* It is now safe to parse the Multiboot information structure + * we saved before from C code. Note that we cannot delay its + * parsing any more because initgdt (called below) needs to make + * use of this information. */ + call _C_LABEL(multiboot_post_reloc) +#endif + subl $NGDT*8, %esp # space for temporary gdt pushl %esp call _C_LABEL(initgdt) addl $4,%esp - + movl _C_LABEL(nkpde),%eax shll $PGSHIFT,%eax addl $TABLESIZE,%eax @@ -692,19 +624,20 @@ begin: call _C_LABEL(main) /* - * void proc_trampoline(void); + * void lwp_trampoline(void); * This is a trampoline function pushed onto the stack of a newly created * process in order to do some additional setup. The trampoline is entered by * cpu_switch()ing to the process, so we abuse the callee-saved registers used * by cpu_switch() to store the information about the stub to call. * NOTE: This function does not have a normal calling sequence! */ -/* LINTSTUB: Func: void proc_trampoline(void) */ -NENTRY(proc_trampoline) -#ifdef MULTIPROCESSOR - call _C_LABEL(proc_trampoline_mp) -#endif - movl $IPL_NONE,CPUVAR(ILEVEL) +/* LINTSTUB: Func: void lwp_trampoline(void) */ +NENTRY(lwp_trampoline) + pushl %ebp + xorl %ebp,%ebp + pushl %eax + call _C_LABEL(lwp_startup) + addl $8,%esp pushl %ebx call *%esi addl $4,%esp @@ -737,881 +670,6 @@ _C_LABEL(esigcode): /*****************************************************************************/ /* - * The following primitives are used to fill and copy regions of memory. - */ - -/* - * XXX No section 9 man page for fillw. - * fillw seems to be very sparsely used (only in pccons it seems.) - * One wonders if it couldn't be done without. - * -- Perry Metzger, May 7, 2001 - */ -/* - * void fillw(short pattern, void *addr, size_t len); - * Write len copies of pattern at addr. - */ -/* LINTSTUB: Func: void fillw(short pattern, void *addr, size_t len) */ -ENTRY(fillw) - pushl %edi - movl 8(%esp),%eax - movl 12(%esp),%edi - movw %ax,%cx - rorl $16,%eax - movw %cx,%ax - cld - movl 16(%esp),%ecx - shrl %ecx # do longwords - rep - stosl - movl 16(%esp),%ecx - andl $1,%ecx # do remainder - rep - stosw - popl %edi - ret - -/* - * int kcopy(const void *from, void *to, size_t len); - * Copy len bytes, abort on fault. - */ -/* LINTSTUB: Func: int kcopy(const void *from, void *to, size_t len) */ -ENTRY(kcopy) - pushl %esi - pushl %edi - GET_CURPCB(%eax) # load curpcb into eax and set on-fault - pushl PCB_ONFAULT(%eax) - movl $_C_LABEL(kcopy_fault), PCB_ONFAULT(%eax) - - movl 16(%esp),%esi - movl 20(%esp),%edi - movl 24(%esp),%ecx - movl %edi,%eax - subl %esi,%eax - cmpl %ecx,%eax # overlapping? - jb 1f - cld # nope, copy forward - shrl $2,%ecx # copy by 32-bit words - rep - movsl - movl 24(%esp),%ecx - andl $3,%ecx # any bytes left? - rep - movsb - - GET_CURPCB(%edx) # XXX save curpcb? - popl PCB_ONFAULT(%edx) - popl %edi - popl %esi - xorl %eax,%eax - ret - - ALIGN_TEXT -1: addl %ecx,%edi # copy backward - addl %ecx,%esi - std - andl $3,%ecx # any fractional bytes? - decl %edi - decl %esi - rep - movsb - movl 24(%esp),%ecx # copy remainder by 32-bit words - shrl $2,%ecx - subl $3,%esi - subl $3,%edi - rep - movsl - cld - - GET_CURPCB(%edx) - popl PCB_ONFAULT(%edx) - popl %edi - popl %esi - xorl %eax,%eax - ret - -/*****************************************************************************/ - -/* - * The following primitives are used to copy data in and out of the user's - * address space. - */ - -/* - * Default to the lowest-common-denominator. We will improve it - * later. - */ -#if defined(I386_CPU) -#define DEFAULT_COPYOUT _C_LABEL(i386_copyout) -#define DEFAULT_COPYIN _C_LABEL(i386_copyin) -#elif defined(I486_CPU) -#define DEFAULT_COPYOUT _C_LABEL(i486_copyout) -#define DEFAULT_COPYIN _C_LABEL(i386_copyin) -#elif defined(I586_CPU) -#define DEFAULT_COPYOUT _C_LABEL(i486_copyout) /* XXX */ -#define DEFAULT_COPYIN _C_LABEL(i386_copyin) /* XXX */ -#elif defined(I686_CPU) -#define DEFAULT_COPYOUT _C_LABEL(i486_copyout) /* XXX */ -#define DEFAULT_COPYIN _C_LABEL(i386_copyin) /* XXX */ -#endif - - .data - - .globl _C_LABEL(copyout_func) -_C_LABEL(copyout_func): - .long DEFAULT_COPYOUT - - .globl _C_LABEL(copyin_func) -_C_LABEL(copyin_func): - .long DEFAULT_COPYIN - - .text - -/* - * int copyout(const void *from, void *to, size_t len); - * Copy len bytes into the user's address space. - * see copyout(9) - */ -/* LINTSTUB: Func: int copyout(const void *kaddr, void *uaddr, size_t len) */ -ENTRY(copyout) - DO_DEFERRED_SWITCH(%eax) - jmp *_C_LABEL(copyout_func) - -#if defined(I386_CPU) -/* LINTSTUB: Func: int i386_copyout(const void *kaddr, void *uaddr, size_t len) */ -ENTRY(i386_copyout) - pushl %esi - pushl %edi - pushl $0 - - movl 16(%esp),%esi - movl 20(%esp),%edi - movl 24(%esp),%eax - - /* - * We check that the end of the destination buffer is not past the end - * of the user's address space. If it's not, then we only need to - * check that each page is writable. The 486 will do this for us; the - * 386 will not. (We assume that pages in user space that are not - * writable by the user are not writable by the kernel either.) - */ - movl %edi,%edx - addl %eax,%edx - jc _C_LABEL(copy_efault) - cmpl $VM_MAXUSER_ADDRESS,%edx - ja _C_LABEL(copy_efault) - - testl %eax,%eax # anything to do? - jz 3f - - /* - * We have to check each PTE for (write) permission, since the CPU - * doesn't do it for us. - */ - - /* Compute number of pages. */ - movl %edi,%ecx - andl $PGOFSET,%ecx - addl %eax,%ecx - decl %ecx - shrl $PGSHIFT,%ecx - - /* Compute PTE offset for start address. */ - shrl $PGSHIFT,%edi - - GET_CURPCB(%edx) - movl $2f,PCB_ONFAULT(%edx) - -1: /* Check PTE for each page. */ - testb $PG_RW,_C_LABEL(PTmap)(,%edi,4) - jz 2f - -4: incl %edi - decl %ecx - jns 1b - - movl 20(%esp),%edi - movl 24(%esp),%eax - jmp 3f - -2: /* Simulate a trap. */ - pushl %ecx - movl %edi,%eax - shll $PGSHIFT,%eax - pushl %eax - call _C_LABEL(trapwrite) # trapwrite(addr) - addl $4,%esp # pop argument - popl %ecx - testl %eax,%eax # if not ok, return EFAULT - jz 4b - jmp _C_LABEL(copy_efault) - -3: GET_CURPCB(%edx) - movl $_C_LABEL(copy_fault),PCB_ONFAULT(%edx) - - /* bcopy(%esi, %edi, %eax); */ - cld - movl %eax,%ecx - shrl $2,%ecx - rep - movsl - movl %eax,%ecx - andl $3,%ecx - rep - movsb - - popl PCB_ONFAULT(%edx) - popl %edi - popl %esi - xorl %eax,%eax - ret -#endif /* I386_CPU */ - -#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) -/* LINTSTUB: Func: int i486_copyout(const void *kaddr, void *uaddr, size_t len) */ -ENTRY(i486_copyout) - pushl %esi - pushl %edi - pushl $0 - - movl 16(%esp),%esi - movl 20(%esp),%edi - movl 24(%esp),%eax - - /* - * We check that the end of the destination buffer is not past the end - * of the user's address space. - */ - movl %edi,%edx - addl %eax,%edx - jc _C_LABEL(copy_efault) - cmpl $VM_MAXUSER_ADDRESS,%edx - ja _C_LABEL(copy_efault) - - GET_CURPCB(%edx) - movl $_C_LABEL(copy_fault),PCB_ONFAULT(%edx) - - /* bcopy(%esi, %edi, %eax); */ - cld - movl %eax,%ecx - shrl $2,%ecx - rep - movsl - movl %eax,%ecx - andl $3,%ecx - rep - movsb - - popl PCB_ONFAULT(%edx) - popl %edi - popl %esi - xorl %eax,%eax - ret -#endif /* I486_CPU || I586_CPU || I686_CPU */ - -/* - * int copyin(const void *from, void *to, size_t len); - * Copy len bytes from the user's address space. - * see copyin(9) - */ -/* LINTSTUB: Func: int copyin(const void *uaddr, void *kaddr, size_t len) */ -ENTRY(copyin) - DO_DEFERRED_SWITCH(%eax) - jmp *_C_LABEL(copyin_func) - -#if defined(I386_CPU) || defined(I486_CPU) || defined(I586_CPU) || \ - defined(I686_CPU) -/* LINTSTUB: Func: int i386_copyin(const void *uaddr, void *kaddr, size_t len) */ -ENTRY(i386_copyin) - pushl %esi - pushl %edi - GET_CURPCB(%eax) - pushl $0 - movl $_C_LABEL(copy_fault),PCB_ONFAULT(%eax) - - movl 16(%esp),%esi - movl 20(%esp),%edi - movl 24(%esp),%eax - - /* - * We check that the end of the destination buffer is not past the end - * of the user's address space. If it's not, then we only need to - * check that each page is readable, and the CPU will do that for us. - */ - movl %esi,%edx - addl %eax,%edx - jc _C_LABEL(copy_efault) - cmpl $VM_MAXUSER_ADDRESS,%edx - ja _C_LABEL(copy_efault) - - /* bcopy(%esi, %edi, %eax); */ - cld - movl %eax,%ecx - shrl $2,%ecx - rep - movsl - movl %eax,%ecx - andl $3,%ecx - rep - movsb - - GET_CURPCB(%edx) - popl PCB_ONFAULT(%edx) - popl %edi - popl %esi - xorl %eax,%eax - ret -#endif /* I386_CPU || I486_CPU || I586_CPU || I686_CPU */ - -/* LINTSTUB: Ignore */ -NENTRY(copy_efault) - movl $EFAULT,%eax - -/* - * kcopy_fault is used by kcopy and copy_fault is used by copyin/out. - * - * they're distinguished for lazy pmap switching. see trap(). - */ -/* LINTSTUB: Ignore */ -NENTRY(kcopy_fault) - GET_CURPCB(%edx) - popl PCB_ONFAULT(%edx) - popl %edi - popl %esi - ret - -/* LINTSTUB: Ignore */ -NENTRY(copy_fault) - GET_CURPCB(%edx) - popl PCB_ONFAULT(%edx) - popl %edi - popl %esi - ret - -/* - * int copyoutstr(const void *from, void *to, size_t maxlen, size_t *lencopied); - * Copy a NUL-terminated string, at most maxlen characters long, into the - * user's address space. Return the number of characters copied (including the - * NUL) in *lencopied. If the string is too long, return ENAMETOOLONG; else - * return 0 or EFAULT. - * see copyoutstr(9) - */ -/* LINTSTUB: Func: int copyoutstr(const void *kaddr, void *uaddr, size_t len, size_t *done) */ -ENTRY(copyoutstr) - pushl %esi - pushl %edi - - DO_DEFERRED_SWITCH(%eax) - - movl 12(%esp),%esi # esi = from - movl 16(%esp),%edi # edi = to - movl 20(%esp),%edx # edx = maxlen - -#if defined(I386_CPU) -#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) - cmpl $CPUCLASS_386,_C_LABEL(cpu_class) - jne 5f -#endif /* I486_CPU || I586_CPU || I686_CPU */ - - /* Compute number of bytes in first page. */ - movl %edi,%eax - andl $PGOFSET,%eax - movl $PAGE_SIZE,%ecx - subl %eax,%ecx # ecx = PAGE_SIZE - (src % PAGE_SIZE) - - GET_CURPCB(%eax) - movl $6f,PCB_ONFAULT(%eax) - -1: /* - * Once per page, check that we are still within the bounds of user - * space, and check for a write fault. - */ - cmpl $VM_MAXUSER_ADDRESS,%edi - jae _C_LABEL(copystr_efault) - - /* Compute PTE offset. */ - movl %edi,%eax - shrl $PGSHIFT,%eax # calculate pte address - - testb $PG_RW,_C_LABEL(PTmap)(,%eax,4) - jnz 2f - -6: /* Simulate a trap. */ - pushl %edx - pushl %edi - call _C_LABEL(trapwrite) # trapwrite(addr) - addl $4,%esp # clear argument from stack - popl %edx - testl %eax,%eax - jnz _C_LABEL(copystr_efault) - -2: /* Copy up to end of this page. */ - subl %ecx,%edx # predecrement total count - jnc 3f - addl %edx,%ecx # ecx += (edx - ecx) = edx - xorl %edx,%edx - -3: decl %ecx - js 4f - lodsb - stosb - testb %al,%al - jnz 3b - - /* Success -- 0 byte reached. */ - addl %ecx,%edx # add back residual for this page - xorl %eax,%eax - jmp copystr_return - -4: /* Go to next page, if any. */ - movl $PAGE_SIZE,%ecx - testl %edx,%edx - jnz 1b - - /* edx is zero -- return ENAMETOOLONG. */ - movl $ENAMETOOLONG,%eax - jmp copystr_return -#endif /* I386_CPU */ - -#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) -5: GET_CURPCB(%eax) - movl $_C_LABEL(copystr_fault),PCB_ONFAULT(%eax) - /* - * Get min(%edx, VM_MAXUSER_ADDRESS-%edi). - */ - movl $VM_MAXUSER_ADDRESS,%eax - subl %edi,%eax - cmpl %edx,%eax - jae 1f - movl %eax,%edx - movl %eax,20(%esp) - -1: incl %edx - cld - -1: decl %edx - jz 2f - lodsb - stosb - testb %al,%al - jnz 1b - - /* Success -- 0 byte reached. */ - decl %edx - xorl %eax,%eax - jmp copystr_return - -2: /* edx is zero -- return EFAULT or ENAMETOOLONG. */ - cmpl $VM_MAXUSER_ADDRESS,%edi - jae _C_LABEL(copystr_efault) - movl $ENAMETOOLONG,%eax - jmp copystr_return -#endif /* I486_CPU || I586_CPU || I686_CPU */ - -/* - * int copyinstr(const void *from, void *to, size_t maxlen, size_t *lencopied); - * Copy a NUL-terminated string, at most maxlen characters long, from the - * user's address space. Return the number of characters copied (including the - * NUL) in *lencopied. If the string is too long, return ENAMETOOLONG; else - * return 0 or EFAULT. - * see copyinstr(9) - */ -/* LINTSTUB: Func: int copyinstr(const void *uaddr, void *kaddr, size_t len, size_t *done) */ -ENTRY(copyinstr) - pushl %esi - pushl %edi - - DO_DEFERRED_SWITCH(%eax) - - GET_CURPCB(%ecx) - movl $_C_LABEL(copystr_fault),PCB_ONFAULT(%ecx) - - movl 12(%esp),%esi # %esi = from - movl 16(%esp),%edi # %edi = to - movl 20(%esp),%edx # %edx = maxlen - - /* - * Get min(%edx, VM_MAXUSER_ADDRESS-%esi). - */ - movl $VM_MAXUSER_ADDRESS,%eax - subl %esi,%eax - cmpl %edx,%eax - jae 1f - movl %eax,%edx - movl %eax,20(%esp) - -1: incl %edx - cld - -1: decl %edx - jz 2f - lodsb - stosb - testb %al,%al - jnz 1b - - /* Success -- 0 byte reached. */ - decl %edx - xorl %eax,%eax - jmp copystr_return - -2: /* edx is zero -- return EFAULT or ENAMETOOLONG. */ - cmpl $VM_MAXUSER_ADDRESS,%esi - jae _C_LABEL(copystr_efault) - movl $ENAMETOOLONG,%eax - jmp copystr_return - -/* LINTSTUB: Ignore */ -NENTRY(copystr_efault) - movl $EFAULT,%eax - -/* LINTSTUB: Ignore */ -NENTRY(copystr_fault) -copystr_return: - /* Set *lencopied and return %eax. */ - GET_CURPCB(%ecx) - movl $0,PCB_ONFAULT(%ecx) - movl 20(%esp),%ecx - subl %edx,%ecx - movl 24(%esp),%edx - testl %edx,%edx - jz 8f - movl %ecx,(%edx) - -8: popl %edi - popl %esi - ret - -/* - * int copystr(const void *from, void *to, size_t maxlen, size_t *lencopied); - * Copy a NUL-terminated string, at most maxlen characters long. Return the - * number of characters copied (including the NUL) in *lencopied. If the - * string is too long, return ENAMETOOLONG; else return 0. - * see copystr(9) - */ -/* LINTSTUB: Func: int copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *done) */ -ENTRY(copystr) - pushl %esi - pushl %edi - - movl 12(%esp),%esi # esi = from - movl 16(%esp),%edi # edi = to - movl 20(%esp),%edx # edx = maxlen - incl %edx - cld - -1: decl %edx - jz 4f - lodsb - stosb - testb %al,%al - jnz 1b - - /* Success -- 0 byte reached. */ - decl %edx - xorl %eax,%eax - jmp 6f - -4: /* edx is zero -- return ENAMETOOLONG. */ - movl $ENAMETOOLONG,%eax - -6: /* Set *lencopied and return %eax. */ - movl 20(%esp),%ecx - subl %edx,%ecx - movl 24(%esp),%edx - testl %edx,%edx - jz 7f - movl %ecx,(%edx) - -7: popl %edi - popl %esi - ret - -/* - * long fuword(const void *uaddr); - * Fetch an int from the user's address space. - * see fuword(9) - */ -/* LINTSTUB: Func: long fuword(const void *base) */ -ENTRY(fuword) - DO_DEFERRED_SWITCH(%eax) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-4,%edx - ja _C_LABEL(fusuaddrfault) - GET_CURPCB(%ecx) - movl $_C_LABEL(fusufault),PCB_ONFAULT(%ecx) - movl (%edx),%eax - movl $0,PCB_ONFAULT(%ecx) - ret - -/* - * int fusword(const void *uaddr); - * Fetch a short from the user's address space. - * see fusword(9) - */ -/* LINTSTUB: Func: int fusword(const void *base) */ -ENTRY(fusword) - DO_DEFERRED_SWITCH(%eax) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-2,%edx - ja _C_LABEL(fusuaddrfault) - GET_CURPCB(%ecx) - movl $_C_LABEL(fusufault),PCB_ONFAULT(%ecx) - movzwl (%edx),%eax - movl $0,PCB_ONFAULT(%ecx) - ret - -/* - * int fuswintr(const void *uaddr); - * Fetch a short from the user's address space. Can be called during an - * interrupt. - * see fuswintr(9) - */ -/* LINTSTUB: Func: int fuswintr(const void *base) */ -ENTRY(fuswintr) - cmpl $TLBSTATE_VALID, CPUVAR(TLBSTATE) - jnz _C_LABEL(fusuaddrfault) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-2,%edx - ja _C_LABEL(fusuaddrfault) - movl CPUVAR(CURLWP),%ecx - movl L_ADDR(%ecx),%ecx - movl $_C_LABEL(fusubail),PCB_ONFAULT(%ecx) - movzwl (%edx),%eax - movl $0,PCB_ONFAULT(%ecx) - ret - -/* - * int fubyte(const void *uaddr); - * Fetch a byte from the user's address space. - * see fubyte(9) - */ -/* LINTSTUB: Func: int fubyte(const void *base) */ -ENTRY(fubyte) - DO_DEFERRED_SWITCH(%eax) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-1,%edx - ja _C_LABEL(fusuaddrfault) - GET_CURPCB(%ecx) - movl $_C_LABEL(fusufault),PCB_ONFAULT(%ecx) - movzbl (%edx),%eax - movl $0,PCB_ONFAULT(%ecx) - ret - -/* - * Handle faults from [fs]u*(). Clean up and return -1. - */ -/* LINTSTUB: Ignore */ -NENTRY(fusufault) - movl $0,PCB_ONFAULT(%ecx) - movl $-1,%eax - ret - -/* - * Handle faults from [fs]u*(). Clean up and return -1. This differs from - * fusufault() in that trap() will recognize it and return immediately rather - * than trying to page fault. - */ -/* LINTSTUB: Ignore */ -NENTRY(fusubail) - movl $0,PCB_ONFAULT(%ecx) - movl $-1,%eax - ret - -/* - * Handle earlier faults from [fs]u*(), due to our of range addresses. - */ -/* LINTSTUB: Ignore */ -NENTRY(fusuaddrfault) - movl $-1,%eax - ret - -/* - * int suword(void *uaddr, long x); - * Store an int in the user's address space. - * see suword(9) - */ -/* LINTSTUB: Func: int suword(void *base, long c) */ -ENTRY(suword) - DO_DEFERRED_SWITCH(%eax) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-4,%edx - ja _C_LABEL(fusuaddrfault) - -#if defined(I386_CPU) -#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) - cmpl $CPUCLASS_386,_C_LABEL(cpu_class) - jne 2f -#endif /* I486_CPU || I586_CPU || I686_CPU */ - - GET_CURPCB(%eax) - movl $3f,PCB_ONFAULT(%eax) - - movl %edx,%eax - shrl $PGSHIFT,%eax # calculate pte address - testb $PG_RW,_C_LABEL(PTmap)(,%eax,4) - jnz 1f - -3: /* Simulate a trap. */ - pushl %edx - pushl %edx - call _C_LABEL(trapwrite) # trapwrite(addr) - addl $4,%esp # clear parameter from the stack - popl %edx - GET_CURPCB(%ecx) - testl %eax,%eax - jnz _C_LABEL(fusufault) - -1: /* XXX also need to check the following 3 bytes for validity! */ -#endif - -2: GET_CURPCB(%ecx) - movl $_C_LABEL(fusufault),PCB_ONFAULT(%ecx) - - movl 8(%esp),%eax - movl %eax,(%edx) - xorl %eax,%eax - movl %eax,PCB_ONFAULT(%ecx) - ret - -/* - * int susword(void *uaddr, short x); - * Store a short in the user's address space. - * see susword(9) - */ -/* LINTSTUB: Func: int susword(void *base, short c) */ -ENTRY(susword) - DO_DEFERRED_SWITCH(%eax) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-2,%edx - ja _C_LABEL(fusuaddrfault) - -#if defined(I386_CPU) -#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) - cmpl $CPUCLASS_386,_C_LABEL(cpu_class) - jne 2f -#endif /* I486_CPU || I586_CPU || I686_CPU */ - - GET_CURPCB(%eax) - movl $3f,PCB_ONFAULT(%eax) - - movl %edx,%eax - shrl $PGSHIFT,%eax # calculate pte address - testb $PG_RW,_C_LABEL(PTmap)(,%eax,4) - jnz 1f - -3: /* Simulate a trap. */ - pushl %edx - pushl %edx - call _C_LABEL(trapwrite) # trapwrite(addr) - addl $4,%esp # clear parameter from the stack - popl %edx - GET_CURPCB(%ecx) - testl %eax,%eax - jnz _C_LABEL(fusufault) - -1: /* XXX also need to check the following byte for validity! */ -#endif - -2: GET_CURPCB(%ecx) - movl $_C_LABEL(fusufault),PCB_ONFAULT(%ecx) - - movl 8(%esp),%eax - movw %ax,(%edx) - xorl %eax,%eax - movl %eax,PCB_ONFAULT(%ecx) - ret - -/* - * int suswintr(void *uaddr, short x); - * Store a short in the user's address space. Can be called during an - * interrupt. - * see suswintr(9) - */ -/* LINTSTUB: Func: int suswintr(void *base, short c) */ -ENTRY(suswintr) - cmpl $TLBSTATE_VALID, CPUVAR(TLBSTATE) - jnz _C_LABEL(fusuaddrfault) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-2,%edx - ja _C_LABEL(fusuaddrfault) - movl CPUVAR(CURLWP),%ecx - movl L_ADDR(%ecx),%ecx - movl $_C_LABEL(fusubail),PCB_ONFAULT(%ecx) - -#if defined(I386_CPU) -#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) - cmpl $CPUCLASS_386,_C_LABEL(cpu_class) - jne 2f -#endif /* I486_CPU || I586_CPU || I686_CPU */ - - movl %edx,%eax - shrl $PGSHIFT,%eax # calculate pte address - testb $PG_RW,_C_LABEL(PTmap)(,%eax,4) - jnz 1f - - /* Simulate a trap. */ - jmp _C_LABEL(fusubail) - -1: /* XXX also need to check the following byte for validity! */ -#endif - -2: movl 8(%esp),%eax - movw %ax,(%edx) - xorl %eax,%eax - movl %eax,PCB_ONFAULT(%ecx) - ret - -/* - * int subyte(void *uaddr, char x); - * Store a byte in the user's address space. - * see subyte(9) - */ -/* LINTSTUB: Func: int subyte(void *base, int c) */ -ENTRY(subyte) - DO_DEFERRED_SWITCH(%eax) - movl 4(%esp),%edx - cmpl $VM_MAXUSER_ADDRESS-1,%edx - ja _C_LABEL(fusuaddrfault) - -#if defined(I386_CPU) -#if defined(I486_CPU) || defined(I586_CPU) || defined(I686_CPU) - cmpl $CPUCLASS_386,_C_LABEL(cpu_class) - jne 2f -#endif /* I486_CPU || I586_CPU || I686_CPU */ - - GET_CURPCB(%eax) - movl $3f,PCB_ONFAULT(%eax) - - movl %edx,%eax - shrl $PGSHIFT,%eax # calculate pte address - testb $PG_RW,_C_LABEL(PTmap)(,%eax,4) - jnz 1f - -3: /* Simulate a trap. */ - pushl %edx - pushl %edx - call _C_LABEL(trapwrite) # trapwrite(addr) - addl $4,%esp # clear parameter from the stack - popl %edx - GET_CURPCB(%ecx) - testl %eax,%eax - jnz _C_LABEL(fusufault) - -1: -#endif - -2: GET_CURPCB(%ecx) - movl $_C_LABEL(fusufault),PCB_ONFAULT(%ecx) - - movb 8(%esp),%al - movb %al,(%edx) - xorl %eax,%eax - movl %eax,PCB_ONFAULT(%ecx) - ret - -/*****************************************************************************/ - -/* * The following is i386-specific nonsense. */ @@ -1645,6 +703,13 @@ NENTRY(lgdt) pushl %eax lret +NENTRY(x86_flush) + /* Reload code selector by doing intersegment return. */ + popl %eax + pushl $GSEL(GCODE_SEL, SEL_KPL) + pushl %eax + lret + /*****************************************************************************/ /* @@ -1680,7 +745,6 @@ ENTRY(longjmp) /*****************************************************************************/ - .globl _C_LABEL(sched_whichqs),_C_LABEL(sched_qs) .globl _C_LABEL(uvmexp),_C_LABEL(panic) #ifdef DIAGNOSTIC @@ -1692,254 +756,65 @@ NENTRY(switch_error) #endif /* DIAGNOSTIC */ /* - * void cpu_switch(struct lwp *) - * Find a runnable process and switch to it. Wait if necessary. If the new - * process is the same as the old one, we short-circuit the context save and - * restore. - * + * struct lwp *cpu_switchto(struct lwp *oldlwp, struct newlwp) + * + * 1. if (oldlwp != NULL), save its context. + * 2. then, restore context of newlwp. + * * Note that the stack frame layout is known to "struct switchframe" - * in and to the code in cpu_fork() which initializes + * in and to the code in cpu_lwp_fork() which initializes * it for a new lwp. */ -ENTRY(cpu_switch) +ENTRY(cpu_switchto) pushl %ebx pushl %esi pushl %edi -#ifdef DEBUG - cmpl $IPL_SCHED,CPUVAR(ILEVEL) - jae 1f - pushl $2f - call _C_LABEL(panic) - /* NOTREACHED */ -2: .asciz "not splsched() in cpu_switch!" -1: -#endif /* DEBUG */ - - movl 16(%esp),%esi # current - - /* - * Clear curlwp so that we don't accumulate system time while idle. - * This also insures that schedcpu() will move the old lwp to - * the correct queue if it happens to get called from the spllower() - * below and changes the priority. (See corresponding comment in - * userret()). - */ - movl $0,CPUVAR(CURLWP) - /* - * First phase: find new lwp. - * - * Registers: - * %eax - queue head, scratch, then zero - * %ebx - queue number - * %ecx - cached value of whichqs - * %edx - next lwp in queue - * %esi - old lwp - * %edi - new lwp - */ + movl 16(%esp),%esi # oldlwp + movl 20(%esp),%edi # newlwp - /* Look for new lwp. */ - cli # splhigh doesn't do a cli - movl _C_LABEL(sched_whichqs),%ecx - bsfl %ecx,%ebx # find a full q - jnz switch_dequeue + testl %esi,%esi + jz switch_skipsave /* - * idling: save old context. - * - * Registers: - * %eax, %ecx - scratch - * %esi - old lwp, then old pcb - * %edi - idle pcb + * Save old context. */ - pushl %esi - call _C_LABEL(pmap_deactivate2) # pmap_deactivate(oldproc) - addl $4,%esp - - movl L_ADDR(%esi),%esi - - /* Save stack pointers. */ - movl %esp,PCB_ESP(%esi) - movl %ebp,PCB_EBP(%esi) + movl L_ADDR(%esi),%eax + movl %esp,PCB_ESP(%eax) + movl %ebp,PCB_EBP(%eax) - /* Find idle PCB for this CPU */ -#ifndef MULTIPROCESSOR - movl $_C_LABEL(lwp0),%ebx - movl L_ADDR(%ebx),%edi - movl L_MD_TSS_SEL(%ebx),%edx -#else - movl CPUVAR(IDLE_PCB),%edi - movl CPUVAR(IDLE_TSS_SEL),%edx -#endif - movl $0,CPUVAR(CURLWP) /* In case we fault... */ - - /* Restore the idle context (avoid interrupts) */ - cli - - /* Restore stack pointers. */ - movl PCB_ESP(%edi),%esp - movl PCB_EBP(%edi),%ebp - - /* Switch TSS. Reset "task busy" flag before loading. */ - movl %cr3,%eax - movl %eax,PCB_CR3(%edi) -#ifdef MULTIPROCESSOR - movl CPUVAR(GDT),%eax -#else - movl _C_LABEL(gdt),%eax -#endif - andl $~0x0200,4-SEL_KPL(%eax,%edx,1) - ltr %dx - - /* We're always in the kernel, so we don't need the LDT. */ - - /* Restore cr0 (including FPU state). */ - movl PCB_CR0(%edi),%ecx - movl %ecx,%cr0 - - /* Record new pcb. */ - SET_CURPCB(%edi) - - xorl %esi,%esi - sti -idle_unlock: -#if defined(MULTIPROCESSOR) || defined(LOCKDEBUG) - call _C_LABEL(sched_unlock_idle) -#endif - /* Interrupts are okay again. */ - pushl $IPL_NONE # spl0() - call _C_LABEL(Xspllower) # process pending interrupts - addl $4,%esp - jmp idle_start -idle_zero: - sti - call _C_LABEL(uvm_pageidlezero) - cli - cmpl $0,_C_LABEL(sched_whichqs) - jnz idle_exit -idle_loop: - /* Try to zero some pages. */ - movl _C_LABEL(uvm)+UVM_PAGE_IDLE_ZERO,%ecx - testl %ecx,%ecx - jnz idle_zero - sti - hlt -NENTRY(mpidle) -idle_start: - cli - cmpl $0,_C_LABEL(sched_whichqs) - jz idle_loop -idle_exit: - movl $IPL_HIGH,CPUVAR(ILEVEL) # splhigh - sti -#if defined(MULTIPROCESSOR) || defined(LOCKDEBUG) - call _C_LABEL(sched_lock_idle) -#endif - movl _C_LABEL(sched_whichqs),%ecx - bsfl %ecx,%ebx - jz idle_unlock - -switch_dequeue: - /* - * we're running at splhigh(), but it's otherwise okay to take - * interrupts here. - */ - sti - leal _C_LABEL(sched_qs)(,%ebx,8),%eax # select q - - movl L_FORW(%eax),%edi # unlink from front of process q -#ifdef DIAGNOSTIC - cmpl %edi,%eax # linked to self (i.e. nothing queued)? - je _C_LABEL(switch_error) # not possible -#endif /* DIAGNOSTIC */ - movl L_FORW(%edi),%edx - movl %edx,L_FORW(%eax) - movl %eax,L_BACK(%edx) - - cmpl %edx,%eax # q empty? - jne 3f - - btrl %ebx,%ecx # yes, clear to indicate empty - movl %ecx,_C_LABEL(sched_whichqs) # update q status - -3: /* We just did it. */ - xorl %eax,%eax - CLEAR_RESCHED(%eax) - -switch_resume: -#ifdef DIAGNOSTIC - cmpl %eax,L_WCHAN(%edi) # Waiting for something? - jne _C_LABEL(switch_error) # Yes; shouldn't be queued. - cmpb $LSRUN,L_STAT(%edi) # In run state? - jne _C_LABEL(switch_error) # No; shouldn't be queued. -#endif /* DIAGNOSTIC */ - - /* Isolate lwp. XXX Is this necessary? */ - movl %eax,L_BACK(%edi) - - /* Record new lwp. */ - movb $LSONPROC,L_STAT(%edi) # l->l_stat = LSONPROC - SET_CURLWP(%edi,%ecx) - - /* Skip context switch if same lwp. */ - xorl %ebx,%ebx - cmpl %edi,%esi - je switch_return - - /* If old lwp exited, don't bother. */ - testl %esi,%esi - jz switch_exited +switch_skipsave: /* - * Second phase: save old context. - * - * Registers: - * %eax, %ecx - scratch - * %esi - old lwp, then old pcb - * %edi - new lwp + * Switch to newlwp's stack. */ - pushl %esi - call _C_LABEL(pmap_deactivate2) # pmap_deactivate(oldproc) - addl $4,%esp - - movl L_ADDR(%esi),%esi - - /* Save stack pointers. */ - movl %esp,PCB_ESP(%esi) - movl %ebp,PCB_EBP(%esi) + movl L_ADDR(%edi),%ebx + movl PCB_EBP(%ebx),%ebp + movl PCB_ESP(%ebx),%esp -switch_exited: /* - * Third phase: restore saved context. + * Restore the rest of newlwp's context. * * Registers: - * %eax, %ebx, %ecx, %edx - scratch - * %esi - new pcb + * %ebx - new pcb * %edi - new lwp */ - /* No interrupts while loading new state. */ - cli - movl L_ADDR(%edi),%esi - - /* Restore stack pointers. */ - movl PCB_ESP(%esi),%esp - movl PCB_EBP(%esi),%ebp - #if 0 /* Don't bother with the rest if switching to a system process. */ - testl $P_SYSTEM,L_FLAG(%edi); XXX NJWLWP lwp's don't have P_SYSTEM! + testl $LK_SYSTEM,L_FLAG(%edi); jnz switch_restored #endif /* Switch TSS. Reset "task busy" flag before loading. */ movl %cr3,%eax - movl %eax,PCB_CR3(%esi) /* XXX should be done by pmap_activate? */ + movl %eax,PCB_CR3(%ebx) /* for TSS gates */ + #ifdef MULTIPROCESSOR movl CPUVAR(GDT),%eax -#else +#else /* Load TSS info. */ movl _C_LABEL(gdt),%eax #endif @@ -1948,64 +823,47 @@ switch_exited: andl $~0x0200,4(%eax,%edx, 1) ltr %dx - pushl %edi - call _C_LABEL(pmap_activate) # pmap_activate(p) - addl $4,%esp - #if 0 switch_restored: #endif + + movl $0,CPUVAR(RESCHED) + /* Restore cr0 (including FPU state). */ - movl PCB_CR0(%esi),%ecx + cli + movl PCB_CR0(%ebx),%ecx #ifdef MULTIPROCESSOR - /* + /* * If our floating point registers are on a different CPU, - * clear CR0_TS so we'll trap rather than reuse bogus state. + * set CR0_TS so we'll trap rather than reuse bogus state. */ - movl PCB_FPCPU(%esi),%ebx - cmpl CPUVAR(SELF),%ebx + movl PCB_FPCPU(%ebx),%eax + cmpl CPUVAR(SELF),%eax jz 1f orl $CR0_TS,%ecx -1: -#endif +1: +#endif movl %ecx,%cr0 - /* Record new pcb. */ - SET_CURPCB(%esi) - /* Interrupts are okay again. */ sti -/* - * Check for restartable atomic sequences (RAS) - */ - movl CPUVAR(CURLWP),%edi - movl L_PROC(%edi),%esi - cmpl $0,P_RASLIST(%esi) - jne 2f -1: - movl $1,%ebx + /* + * Check for restartable atomic sequences (RAS) + */ -switch_return: -#if defined(MULTIPROCESSOR) || defined(LOCKDEBUG) - call _C_LABEL(sched_unlock_idle) -#endif - cmpl $0,CPUVAR(IPENDING) - jz 3f - pushl $IPL_NONE # spl0() - call _C_LABEL(Xspllower) # process pending interrupts - addl $4,%esp -3: - movl $IPL_HIGH,CPUVAR(ILEVEL) # splhigh() + movl L_PROC(%edi),%ebx + cmpl $0,P_RASLIST(%ebx) + jne check_ras - movl %ebx,%eax - +switch_return: + movl %esi,%eax # return 'oldlwp' popl %edi popl %esi popl %ebx ret -2: # check RAS list +check_ras: movl L_MD_REGS(%edi),%ebx movl TF_EIP(%ebx),%eax pushl %eax @@ -2013,121 +871,9 @@ switch_return: call _C_LABEL(ras_lookup) addl $8,%esp cmpl $-1,%eax - je 1b + je switch_return movl %eax,TF_EIP(%ebx) - jmp 1b - -/* - * void cpu_switchto(struct lwp *current, struct lwp *next) - * Switch to the specified next LWP. - */ -ENTRY(cpu_switchto) - pushl %ebx - pushl %esi - pushl %edi - -#ifdef DEBUG - cmpl $IPL_SCHED,CPUVAR(ILEVEL) - jae 1f - pushl $2f - call _C_LABEL(panic) - /* NOTREACHED */ -2: .asciz "not splsched() in cpu_switchto!" -1: -#endif /* DEBUG */ - - movl 16(%esp),%esi # current - movl 20(%esp),%edi # next - - /* - * Clear curlwp so that we don't accumulate system time while idle. - * This also insures that schedcpu() will move the old process to - * the correct queue if it happens to get called from the spllower() - * below and changes the priority. (See corresponding comment in - * usrret()). - * - * XXX Is this necessary? We know we won't go idle. - */ - movl $0,CPUVAR(CURLWP) - - /* - * We're running at splhigh(), but it's otherwise okay to take - * interrupts here. - */ - sti - - /* Jump into the middle of cpu_switch */ - xorl %eax,%eax - jmp switch_resume - -/* - * void cpu_exit(struct lwp *l) - * Switch to the appropriate idle context (lwp0's if uniprocessor; the CPU's - * if multiprocessor) and deallocate the address space and kernel stack for p. - * Then jump into cpu_switch(), as if we were in the idle proc all along. - */ -#ifndef MULTIPROCESSOR - .globl _C_LABEL(lwp0) -#endif - .globl _C_LABEL(uvmspace_free),_C_LABEL(kernel_map) - .globl _C_LABEL(uvm_km_free),_C_LABEL(tss_free) -/* LINTSTUB: Func: void cpu_exit(struct lwp *l) */ -ENTRY(cpu_exit) - movl 4(%esp),%edi # old process -#ifndef MULTIPROCESSOR - movl $_C_LABEL(lwp0),%ebx - movl L_ADDR(%ebx),%esi - movl L_MD_TSS_SEL(%ebx),%edx -#else - movl CPUVAR(IDLE_PCB),%esi - movl CPUVAR(IDLE_TSS_SEL),%edx -#endif - /* In case we fault... */ - movl $0,CPUVAR(CURLWP) - - /* Restore the idle context. */ - cli - - /* Restore stack pointers. */ - movl PCB_ESP(%esi),%esp - movl PCB_EBP(%esi),%ebp - - /* Switch TSS. Reset "task busy" flag before loading. */ - movl %cr3,%eax - movl %eax,PCB_CR3(%esi) -#ifdef MULTIPROCESSOR - movl CPUVAR(GDT),%eax -#else - /* Load TSS info. */ - movl _C_LABEL(gdt),%eax -#endif - - andl $~0x0200,4-SEL_KPL(%eax,%edx,1) - ltr %dx - - /* We're always in the kernel, so we don't need the LDT. */ - - /* Restore cr0 (including FPU state). */ - movl PCB_CR0(%esi),%ecx - movl %ecx,%cr0 - - /* Record new pcb. */ - SET_CURPCB(%esi) - - /* Interrupts are okay again. */ - sti - - /* - * Schedule the dead LWP's stack to be freed. - */ - pushl %edi - call _C_LABEL(lwp_exit2) - addl $4,%esp - - /* Jump into cpu_switch() with the right state. */ - xorl %esi,%esi - movl %esi,CPUVAR(CURLWP) - jmp idle_start + jmp switch_return /* * void savectx(struct pcb *pcb); @@ -2135,8 +881,8 @@ ENTRY(cpu_exit) */ /* LINTSTUB: Func: void savectx(struct pcb *pcb) */ ENTRY(savectx) - movl 4(%esp),%edx # edx = p->p_addr - + movl 4(%esp),%edx # edx = pcb + /* Save stack pointers. */ movl %esp,PCB_ESP(%edx) movl %ebp,PCB_EBP(%edx) @@ -2180,7 +926,7 @@ syscall1: #ifdef DDB int $3 #endif -1: +1: #endif /* DIAGNOSTIC */ movl CPUVAR(CURLWP),%edx movl %esp,L_MD_REGS(%edx) # save pointer to frame @@ -2219,8 +965,8 @@ syscall1: movl $IPL_NONE,CPUVAR(ILEVEL) jmp 2b 4: .asciz "WARNING: SPL NOT LOWERED ON SYSCALL EXIT\n" -5: .asciz "WARNING: SPL NOT ZERO ON SYSCALL ENTRY\n" -6: .asciz "WARNING: WANT PMAPLOAD ON SYSCALL ENTRY\n" +5: .asciz "WARNING: SPL NOT ZERO ON SYSCALL ENTRY\n" +6: .asciz "WARNING: WANT PMAPLOAD ON SYSCALL ENTRY\n" #endif /* DIAGNOSTIC */ 9: sti call _C_LABEL(pmap_load)