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 1.47.4.8 retrieving revision 1.48.8.1 diff -u -p -r1.47.4.8 -r1.48.8.1 --- src/sys/arch/i386/i386/locore.S 2007/10/23 20:13:02 1.47.4.8 +++ src/sys/arch/i386/i386/locore.S 2007/09/03 16:47:23 1.48.8.1 @@ -1,44 +1,4 @@ -/* $NetBSD: locore.S,v 1.47.4.8 2007/10/23 20:13:02 ad Exp $ */ - -/* - * Copyright-o-rama! - */ - -/* - * Copyright (c) 2001 Wasabi Systems, Inc. - * All rights reserved. - * - * Written by Frank van der Linden for Wasabi Systems, Inc. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed for the NetBSD Project by - * Wasabi Systems, Inc. - * 4. The name of Wasabi Systems, Inc. may not be used to endorse - * or promote products derived from this software without specific prior - * written permission. - * - * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED - * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR - * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC - * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR - * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF - * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS - * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN - * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) - * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - * POSSIBILITY OF SUCH DAMAGE. - */ - +/* $NetBSD: locore.S,v 1.48.8.1 2007/09/03 16:47:23 jmcneill Exp $ */ /*- * Copyright (c) 1998, 2000, 2004, 2006, 2007 The NetBSD Foundation, Inc. @@ -179,7 +139,6 @@ _C_LABEL(cpu): .long 0 # are we 80486, _C_LABEL(atdevbase): .long 0 # location of start of iomem in virtual _C_LABEL(proc0uarea): .long 0 _C_LABEL(PDPpaddr): .long 0 # paddr of PDP, for libkvm -_C_LABEL(tablesize): .long 0 .space 512 tmpstk: @@ -425,27 +384,13 @@ try586: /* Use the `cpuid' instruction. /* * Virtual address space of kernel: * - * text | data | bss | [syms] | page dir | proc0 kstack | L1 ptp + * text | data | bss | [syms] | page dir | proc0 kstack * 0 1 2 3 */ - -#define PROC0_PDIR_OFF 0 -#define PROC0_STK_OFF (PROC0_PDIR_OFF + PAGE_SIZE) -#define PROC0_PTP1_OFF (PROC0_STK_OFF + UPAGES * PAGE_SIZE) - -/* - * fillkpt - * eax = pte (page frame | control | status) - * ebx = page table address - * ecx = number of pages to map - */ - -#define fillkpt \ -1: movl %eax,(%ebx) ; /* store phys addr */ \ - addl $4,%ebx ; /* next pte/pde */ \ - addl $PAGE_SIZE,%eax ; /* next phys page */ \ - loop 1b ; \ - +#define PROC0PDIR ((0) * PAGE_SIZE) +#define PROC0STACK ((1) * PAGE_SIZE) +#define SYSMAP ((1+UPAGES) * PAGE_SIZE) +#define TABLESIZE ((1+UPAGES) * PAGE_SIZE) /* + nkpde * PAGE_SIZE */ /* Find end of kernel image. */ movl $RELOC(end),%edi @@ -459,60 +404,67 @@ try586: /* Use the `cpuid' instruction. 1: #endif - /* Compute sizes */ + /* Calculate where to start the bootstrap tables. */ movl %edi,%esi # edi = esym ? esym : end addl $PGOFSET,%esi # page align up andl $~PGOFSET,%esi - /* nkptp[1] = (esi + ~L2_FRAME) >> L2_SHIFT + 1; */ - movl %esi,%eax - addl $~L2_FRAME,%eax - shrl $L2_SHIFT,%eax - incl %eax /* one more ptp for VAs stolen by bootstrap */ -1: movl %eax,RELOC(nkptp)+1*4 - - /* tablesize = (1 + UPAGES + nkptp) << PGSHIFT; */ - addl $(1+UPAGES),%eax - shll $PGSHIFT,%eax - movl %eax,RELOC(tablesize) - - /* ensure that nkptp covers bootstrap tables */ - addl %esi,%eax - addl $~L2_FRAME,%eax - shrl $L2_SHIFT,%eax - incl %eax - cmpl %eax,RELOC(nkptp)+1*4 - jnz 1b - - /* Clear tables */ - movl %esi,%edi + /* + * Calculate the size of the kernel page table directory, and + * how many entries it will have. Adjust nkpde to the actual + * kernel size automatically. Account for the bootstrap tables, + * round up, and add an extra 4MB. + */ + leal TABLESIZE+NBPD+PDOFSET(%edi),%eax + shrl $PDSHIFT,%eax + movl RELOC(nkpde),%ecx # get nkpde + cmpl %ecx,%eax + jb 1f + movl %eax,%ecx +1: cmpl $NKPTP_MIN,%ecx # larger than min? + jge 1f + movl $NKPTP_MIN,%ecx # set at min + jmp 2f +1: cmpl $NKPTP_MAX,%ecx # larger than max? + jle 2f + movl $NKPTP_MAX,%ecx +2: movl %ecx,RELOC(nkpde) + + /* Clear memory for bootstrap tables. */ + shll $PGSHIFT,%ecx + addl $TABLESIZE,%ecx + addl %esi,%ecx # end of tables + subl %edi,%ecx # size of tables + shrl $2,%ecx xorl %eax,%eax cld - movl RELOC(tablesize),%ecx - shrl $2,%ecx rep stosl - leal (PROC0_PTP1_OFF)(%esi), %ebx +/* + * fillkpt + * eax = pte (page frame | control | status) + * ebx = page table address + * ecx = number of pages to map + */ +#define fillkpt \ +1: movl %eax,(%ebx) ; \ + addl $PAGE_SIZE,%eax ; /* increment physical address */ \ + addl $4,%ebx ; /* next pte */ \ + loop 1b ; /* * Build initial page tables. */ - /* - * Compute &__data_start - KERNBASE. This can't be > 4G, - * or we can't deal with it anyway, since we can't load it in - * 32 bit mode. So use the bottom 32 bits. - */ - movl $RELOC(__data_start),%edx + /* Calculate end of text segment, rounded to a page. */ + leal (RELOC(etext)+PGOFSET),%edx andl $~PGOFSET,%edx - /* - * Skip the first MB. - */ + /* Skip over the first 1MB. */ movl $_RELOC(KERNTEXTOFF),%eax movl %eax,%ecx - shrl $(PGSHIFT-2),%ecx /* ((n >> PGSHIFT) << 2) for # pdes */ - addl %ecx,%ebx + shrl $PGSHIFT,%ecx + leal (SYSMAP)(%esi,%ecx,4),%ebx /* Map the kernel text read-only. */ movl %edx,%ecx @@ -523,13 +475,15 @@ try586: /* Use the `cpuid' instruction. /* Map the data, BSS, and bootstrap tables read-write. */ leal (PG_V|PG_KW)(%edx),%eax - movl RELOC(tablesize),%ecx + movl RELOC(nkpde),%ecx + shll $PGSHIFT,%ecx + addl $TABLESIZE,%ecx addl %esi,%ecx # end of tables subl %edx,%ecx # subtract end of text shrl $PGSHIFT,%ecx fillkpt - /* Map ISA I/O mem (later atdevbase) */ + /* Map ISA I/O memory. */ movl $(IOM_BEGIN|PG_V|PG_KW/*|PG_N*/),%eax # having these bits set movl $(IOM_SIZE>>PGSHIFT),%ecx # for this many pte s, fillkpt @@ -537,40 +491,28 @@ try586: /* Use the `cpuid' instruction. /* * Construct a page table directory. */ - /* Set up top level entries for identity mapping */ - leal (PROC0_PDIR_OFF)(%esi),%ebx - leal (PROC0_PTP1_OFF)(%esi),%eax - orl $(PG_V|PG_KW), %eax - movl RELOC(nkptp)+1*4,%ecx + /* Install PDEs for temporary double map of kernel. */ + movl RELOC(nkpde),%ecx # for this many pde s, + leal (PROC0PDIR+0*4)(%esi),%ebx # which is where temp maps! + leal (SYSMAP+PG_V|PG_KW)(%esi),%eax # pte for KPT in proc 0, fillkpt - /* Set up top level entries for actual kernel mapping */ - leal (PROC0_PDIR_OFF + L2_SLOT_KERNBASE*4)(%esi),%ebx - leal (PROC0_PTP1_OFF)(%esi),%eax - orl $(PG_V|PG_KW), %eax - movl RELOC(nkptp)+1*4,%ecx + /* Map kernel PDEs. */ + movl RELOC(nkpde),%ecx # for this many pde s, + leal (PROC0PDIR+PDSLOT_KERN*4)(%esi),%ebx # kernel pde offset + leal (SYSMAP+PG_V|PG_KW)(%esi),%eax # pte for KPT in proc 0, fillkpt /* Install a PDE recursively mapping page directory as a page table! */ - leal (PROC0_PDIR_OFF + PDIR_SLOT_PTE*4)(%esi),%ebx - leal (PROC0_PDIR_OFF)(%esi),%eax - orl $(PG_V|PG_KW),%eax - movl %eax,(%ebx) - + 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 PDP, for libkvm. */ movl %esi,RELOC(PDPpaddr) - /* - * Startup checklist: - * 1. Load %cr3 with pointer to PDIR. - */ + /* Load base of page directory and enable mapping. */ movl %esi,%eax # phys address of ptd in proc 0 movl %eax,%cr3 # load ptd addr into mmu - - /* - * 2. Enable paging and the rest of it. - */ movl %cr0,%eax # get control word # enable paging & NPX emulation orl $(CR0_PE|CR0_PG|CR0_NE|CR0_TS|CR0_EM|CR0_MP),%eax @@ -580,26 +522,23 @@ try586: /* Use the `cpuid' instruction. ret begin: - /* - * We have arrived. - * There's no need anymore for the identity mapping in low - * memory, remove it. - */ - movl _C_LABEL(nkptp)+1*4,%ecx - leal (PROC0_PDIR_OFF)(%esi),%ebx # old, phys address of PDIR - addl $(KERNBASE), %ebx # new, virtual address of PDIR + /* 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), %ebx # now use relocated address 1: movl $0,(%ebx) - addl $4,%ebx + addl $4,%ebx # next pde loop 1b /* Relocate atdevbase. */ - movl $KERNBASE,%edx - addl _C_LABEL(tablesize),%edx + movl _C_LABEL(nkpde),%edx + shll $PGSHIFT,%edx + addl $(TABLESIZE+KERNBASE),%edx addl %esi,%edx movl %edx,_C_LABEL(atdevbase) /* Set up bootstrap stack. */ - leal (PROC0_STK_OFF+KERNBASE)(%esi),%eax + 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 @@ -618,7 +557,9 @@ begin: call _C_LABEL(initgdt) addl $4,%esp - movl _C_LABEL(tablesize),%eax + movl _C_LABEL(nkpde),%eax + shll $PGSHIFT,%eax + addl $TABLESIZE,%eax addl %esi,%eax # skip past stack and page tables pushl %eax @@ -663,7 +604,7 @@ NENTRY(lwp_trampoline) pushl %ebx call *%esi addl $4,%esp - DO_DEFERRED_SWITCH + DO_DEFERRED_SWITCH(%eax) INTRFASTEXIT /* NOTREACHED */ @@ -689,6 +630,47 @@ NENTRY(sigcode) _C_LABEL(esigcode): /* + * void lgdt(struct region_descriptor *rdp); + * + * Load a new GDT pointer (and do any necessary cleanup). + * XXX It's somewhat questionable whether reloading all the segment registers + * is necessary, since the actual descriptor data is not changed except by + * process creation and exit, both of which clean up via task switches. OTOH, + * this only happens at run time when the GDT is resized. + */ +NENTRY(lgdt) + /* Reload the descriptor table. */ + movl 4(%esp),%eax + lgdt (%eax) + /* Flush the prefetch queue. */ + jmp 1f + nop +1: /* Reload "stale" selectors. */ + movl $GSEL(GDATA_SEL, SEL_KPL),%eax + movw %ax,%ds + movw %ax,%es + movw %ax,%gs + movw %ax,%ss + movl $GSEL(GCPU_SEL, SEL_KPL),%eax + movw %ax,%fs + /* Reload code selector by doing intersegment return. */ + popl %eax + pushl $GSEL(GCODE_SEL, SEL_KPL) + pushl %eax + lret + +/* + * void x86_flush() + * + * Flush instruction pipelines by doing an intersegment (far) return. + */ +NENTRY(x86_flush) + popl %eax + pushl $GSEL(GCODE_SEL, SEL_KPL) + pushl %eax + lret + +/* * int setjmp(label_t *) * * Used primarily by DDB. @@ -723,8 +705,7 @@ ENTRY(longjmp) ret /* - * struct lwp *cpu_switchto(struct lwp *oldlwp, struct newlwp, - * bool returning) + * struct lwp *cpu_switchto(struct lwp *oldlwp, struct newlwp) * * 1. if (oldlwp != NULL), save its context. * 2. then, restore context of newlwp. @@ -740,7 +721,6 @@ ENTRY(cpu_switchto) movl 16(%esp),%esi # oldlwp movl 20(%esp),%edi # newlwp - movl 24(%esp),%edx # returning testl %esi,%esi jz 1f @@ -754,13 +734,6 @@ ENTRY(cpu_switchto) movl PCB_EBP(%ebx),%ebp movl PCB_ESP(%ebx),%esp - /* Set curlwp. */ - movl %edi,CPUVAR(CURLWP) - - /* Skip the rest if returning to a pinned LWP. */ - testl %edx,%edx - jnz 4f - /* Switch TSS. Reset "task busy" flag before loading. */ movl %cr3,%eax movl %eax,PCB_CR3(%ebx) # for TSS gates @@ -769,6 +742,9 @@ ENTRY(cpu_switchto) andl $~0x0200,4(%eax,%edx, 1) ltr %dx + /* Set curlwp. */ + movl %edi,CPUVAR(CURLWP) + /* Don't bother with the rest if switching to a system process. */ testl $LW_SYSTEM,L_FLAG(%edi) jnz 4f @@ -890,7 +866,7 @@ syscall1: call _C_LABEL(trap) addl $4,%esp jmp .Lsyscall_checkast /* re-check ASTs */ -1: CHECK_DEFERRED_SWITCH +1: CHECK_DEFERRED_SWITCH(%eax) jnz 9f #ifndef DIAGNOSTIC INTRFASTEXIT @@ -906,7 +882,7 @@ syscall1: int $3 #endif /* DDB */ movl $IPL_NONE,CPUVAR(ILEVEL) - jmp .Lsyscall_checkast + 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"