src/arch/x86/sysenter.cpp

Idź do dokumentacji tego pliku.

/***********************************************************
*PANALIX 0.06, (c) Adrian Panasiuk 2002-4                  *
*adek336[at]o2.pl, panalix.prv.pl                          *
*under GPLv3 license                                       *
*                                                          *
*panalix - small osdev project                             *
************************************************************
*       sysenter.cpp, version 1.0                          *
************************************************************
*                                                          *
*Sysenter, and the API is here.                            *
*                                                          *
*28'07'04- first revision (1.0)                            *
*                                                          *
***********************************************************/

#include "src/common/shared.hpp"
#include "src/memory/memset.hpp"
#include "src/memory/align.hpp"
#include "src/memory/heap.hpp"
#include "src/thread/process.hpp"
#include "src/thread/scheduler.hpp"
#include "src/module/api1.hpp"
#include "src/arch/x86/gdt.hpp"
#include "src/arch/x86/msr.hpp"
#include "src/arch/x86/interr.hpp"
#include "src/arch/x86/except_c.hpp"
#include "src/arch/x86/sysenter.hpp"

namespace Arch {
namespace x86 {
namespace Sysenter {

const uint32 SYSENTTEMPBUF      = 0x200;
char SysenterTempBuf[SYSENTTEMPBUF];

extern "C" void sysentry();

void init()
 {
union
 {
        uint64 q;
        uint32 l[2];
 } uu;
        uu.l[1] = 0;
/*write sep msr for the code selector*/
        wrmsr(SYSENTER_CS_MSR, GDT::code_sel_kernel);
/*kernel stack pointer*/
        uu.l[0] = (uint32) &SysenterTempBuf[SYSENTTEMPBUF];
        wrmsr(SYSENTER_ESP_MSR, uu.q);
/*kernel entry point*/
        uu.l[0] = (uint32) &sysentry;
        wrmsr(SYSENTER_EIP_MSR, uu.q);
 }

//this is the handler
//upon enter, sysenter requires that the user stack holds 4 ints which can be accessed
int SysEnter(class Arch::x86::Interr::except2_t *code)
 {
env_t env;
int *args;
int i= ESUCCESS;
// blocking routines will only block a single thread
        asm volatile("sti");
//get info
        EnvGet(&env);
        if (env.proc==NULL)
                sysfail("env.proc==NULL ;(((");
        args= (int*)(code->esp);
//process
        switch ( env.proc->env.api ) {
        case API_NONE:
                if (code->r.r_eax + code->r.r_ebx != APIMAGIC)  //checksum
                        ProcFail("bad API_NONE request");
                env.proc->env.api= code->r.r_eax;
                i= ESUCCESS;
                break;
        case API_v1:
                i= API::v1::req(&env,args);
                break;
        default:
                ProcFail("invalid api version");
                break;
         }

        code->r.r_eax= i;
        return ESUCCESS;
 }


   };   /*namespace Sysenter*/
  };    /*namespace x86*/
 };     /*namespace Arch*/


/***********************************************************
*                                                          *
*panalix 0.06 (c) Adrian Panasiuk 2002-4                   *
*adek336[at]o2.pl, panalix.prv.pl                          *
*                                                          *
***********************************************************/

---