unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
memAccess += 2;
// rpta = 0x2400 + RPTI(va);
rpta = tcb[curTask].RPT + RPTI(va);
rpte1 = memory[rpta];
rpte2 = memory[rpta+1];
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
if (DEFINED(rpte1))
{
// printf("\nUPT frame already defined");
// defined
memHits++;
}
else
{
// fault
memPageFaults++;
rptFrame = getFrame(-1);
rpte1 = SET_DEFINED(rptFrame);
if (PAGED(rpte2))
{
//upt is in swap and we need to read it back in
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
}
else
{
//initialize the upt memory
memset(&memory[(rptFrame<<6)], 0, 128);
}
}
memory[rpta] = rpte1 = SET_REF(rpte1);
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
if (DEFINED(upte1))
{
// defined
memHits++;
}
else
{
// fault
memPageFaults++;
uptFrame = getFrame(FRAME(memory[rpta]));
memory[rpta] = rpte1 = SET_REF(SET_DIRTY(rpte1));
upte1 = SET_DEFINED(uptFrame);
if (PAGED(upte2))
{
//get the data frame from swap
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
}
else
{
//we don't need to do anything
//but we could initialize the mem to 0xf025 which is lc-3 halt instruction
memset(&memory[(uptFrame<<6)], 0xf025, 128);
}
}
if (rwFlg) {
upte1 = SET_DIRTY(upte1);
}
memory[upta] = SET_REF(upte1);
memory[upta+1] = upte2;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
return &memory[va];
#endif
} // end getMemAdr
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
extern TCB tcb[MAX_TASKS];
extern int curTask;
//stat
memAccess++;
rpta = tcb[curTask].RPT + RPTI(va); // 0x2400 + RPTI(va);
rpte1 = memory[rpta];
rpte2 = memory[rpta+1];
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
if (DEFINED(rpte1))
{
// defined
//stat
memHits++;
if (rwFlg)
rpte1 = SET_DIRTY(rpte1);
}
else
{
// fault
//stat
memPageFaults++;
rptFrame = getFrame(-1);
rpte1 = SET_DEFINED(rptFrame);
if (PAGED(rpte2))
{
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
//stat
pageReads++;
//clean
if (rwFlg)
rpte1 = SET_DIRTY(rpte1);
else
rpte1 = CLEAR_DIRTY(rpte1);
}
else
{
memset(&memory[(rptFrame<<6)], 0, 128);
//dirty
rpte1 = SET_DIRTY(rpte1);
}
}
rpte1 = SET_PINNED(rpte1);
memory[rpta] = rpte1 = SET_REF(rpte1);
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
//stat
memAccess++;
if (DEFINED(upte1))
{
// defined
//stat
memHits++;
if (rwFlg)
upte1 = SET_DIRTY(upte1);
}
else
{
// fault
//stat
memPageFaults++;
uptFrame = getFrame(FRAME(memory[rpta]));
upte1 = SET_DEFINED(uptFrame);
if (PAGED(upte2))
{
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
//stat
pageReads++;
//clean unless being written to
if (rwFlg)
upte1 = SET_DIRTY(upte1);
else
upte1 = CLEAR_DIRTY(upte1);
}
else
{
//dirty
upte1 = SET_DIRTY(upte1);
}
}
rpte1 = SET_PINNED(rpte1);
memory[rpta] = rpte1;
memory[upta] = upte1 = SET_REF(upte1);
memory[upta+1] = upte2;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
return &memory[va];
#endif
} // end getMemAdr
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
rpta = tcb[curTask].RPT + RPTI(va);
rpte1 = memory[rpta];
rpte2 = memory[rpta+1];
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
if (DEFINED(rpte1))
{
memHits++;
}
else
{
// fault
memPageFaults++;
rptFrame = getFrame(-1);
assert(rptFrame >= 192);
rpte1 = SET_DEFINED(rptFrame);
if (PAGED(rpte2))
{
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
pageReads++;
}
else
{
rpte1 = SET_DIRTY(rpte1); rpte2 = 0;
memset(&memory[(rptFrame<<6)], 0, 128);
}
}
memory[rpta] = rpte1 = SET_REF(rpte1);
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
if (DEFINED(upte1))
{
memHits++;
}
else
{
// fault
memPageFaults++;
uptFrame = getFrame(FRAME(memory[rpta]));
assert(uptFrame >= 192);
upte1 = SET_DEFINED(uptFrame);
if (PAGED(upte2))
{
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
pageReads++;
}
else
{
upte1 = SET_DIRTY(upte1); upte2 = 0;
}
}
if(rwFlg != 0){
upte1 = SET_DIRTY(upte1);
}
memory[upta] = SET_REF(upte1);
memory[upta+1] = upte2;
memAccess = memHits + memPageFaults;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
pa = va;
#endif
return &memory[pa];
} // end getMemAdr
unsigned short int *getMemAdr(int va, int rwFlg)
{
unsigned short int pa;
int rpta, rpte1, rpte2;
int upta, upte1, upte2;
int rptFrame, uptFrame;
rpta = 0x2400 + RPTI(va) + 0x40*curTask; // address of the root page table
rpte1 = memory[rpta]; // get a word
rpte2 = memory[rpta+1]; // get another word
// turn off virtual addressing for system RAM
if (va < 0x3000) return &memory[va];
#if MMU_ENABLE
// printf("using memory Management\n");
if (DEFINED(rpte1))
{
memHits++;
// defined
}
else
{
memPageFaults++;
// fault
rptFrame = getFrame(-1);
rpte1 = SET_DEFINED(rptFrame); // setting the frame bit in the user page table
rpte1 = SET_DIRTY(rpte1);
if (PAGED(rpte2)) // it exists in swap space
{
accessPage(SWAPPAGE(rpte2), rptFrame, PAGE_READ);
}
else
{
memset(&memory[(rptFrame<<6)], 0, 128); //sets 128 bytes to 0 why is it 128? why bitshift by 6?
}
}
memory[rpta] = rpte1 = SET_REF(rpte1); // sets the referenced bit in the root page table
memory[rpta+1] = rpte2;
upta = (FRAME(rpte1)<<6) + UPTI(va);
upte1 = memory[upta];
upte2 = memory[upta+1];
if (DEFINED(upte1))
{
memHits++;
// defined
}
else
{
memPageFaults++;
// fault
uptFrame = getFrame(FRAME(memory[rpta]));
upte1 = SET_DEFINED(uptFrame);
upte1 = SET_DIRTY(upte1);
if (PAGED(upte2))
{
accessPage(SWAPPAGE(upte2), uptFrame, PAGE_READ);
}
else
{
memset(&memory[(uptFrame<<6)], 0, 128); //sets 128 bytes to 0 why is it 128? why bitshift by 6?
}
}
if(rwFlg){
memory[rpta] = SET_DIRTY(memory[rpta]);
}else{
}
memory[upta] = SET_REF(upte1);
memory[upta+1] = upte2;
return &memory[(FRAME(upte1)<<6) + FRAMEOFFSET(va)];
#else
return &memory[va];
#endif
} // end getMemAdr