/*
* This gets called by _pt_fault_handler in mm/pagetable.c The
* calling function has already done a lot of error checking for
* us. In particular it has checked that we are not page faulting
* while in kernel mode. Make sure you understand why an
* unexpected page fault in kernel mode is bad in Weenix. You
* should probably read the _pt_fault_handler function to get a
* sense of what it is doing.
*
* Before you can do anything you need to find the vmarea that
* contains the address that was faulted on. Make sure to check
* the permissions on the area to see if the process has
* permission to do [cause]. If either of these checks does not
* pass kill the offending process, setting its exit status to
* EFAULT (normally we would send the SIGSEGV signal, however
* Weenix does not support signals).
*
* Now it is time to find the correct page (don't forget
* about shadow objects, especially copy-on-write magic!). Make
* sure that if the user writes to the page it will be handled
* correctly.
*
* Finally call pt_map to have the new mapping placed into the
* appropriate page table.
*
* @param vaddr the address that was accessed to cause the fault
*
* @param cause this is the type of operation on the memory
* address which caused the fault, possible values
* can be found in pagefault.h
*/
void
handle_pagefault(uintptr_t vaddr, uint32_t cause)
{
/*NOT_YET_IMPLEMENTED("VM: handle_pagefault");*/
vmmap_t *map = curproc->p_vmmap;
dbginfo(DBG_ERROR, proc_info, curproc);
dbginfo(DBG_ERROR, proc_list_info, NULL);
if(vaddr == NULL){
}
vmarea_t *vma = vmmap_lookup(map, ADDR_TO_PN(vaddr));
/*uintptr_t pagenum = PAGE_OFFSET(vaddr);*/
if(vma == NULL || !(cause & FAULT_USER)){
/*XXX permission checks*/
curproc->p_status = EFAULT;
proc_kill(curproc, EFAULT);
}
pframe_t *pf;
uintptr_t pagenum = ADDR_TO_PN(vaddr) - vma->vma_start+vma->vma_off;
/*XXX handle shadow objects*/
/*
int forWrite = 0;
if(cause & FAULT_WRITE){
forWrite = 1;
}
*/
/*
if(vma->vma_obj->mmo_shadowed != NULL){
shadow_lookuppage(vma->vma_obj->mmo_shadowed, pagenum, forWrite,&pf);
}else{
*/
pframe_get(vma->vma_obj, pagenum, &pf);
/*}*/
uintptr_t paddr = pt_virt_to_phys((uintptr_t)pf->pf_addr);
uintptr_t pdflags = PD_PRESENT | PD_WRITE | PD_USER;
uintptr_t ptflags = PT_PRESENT | PT_WRITE | PT_USER;
/*XXX tlb flush?*/
pt_map(curproc->p_pagedir,(uintptr_t)PAGE_ALIGN_DOWN(vaddr), paddr, pdflags, ptflags);
}
/*
* This gets called by _pt_fault_handler in mm/pagetable.c The
* calling function has already done a lot of error checking for
* us. In particular it has checked that we are not page faulting
* while in kernel mode. Make sure you understand why an
* unexpected page fault in kernel mode is bad in Weenix. You
* should probably read the _pt_fault_handler function to get a
* sense of what it is doing.
*
* Before you can do anything you need to find the vmarea that
* contains the address that was faulted on. Make sure to check
* the permissions on the area to see if the process has
* permission to do [cause]. If either of these checks does not
* pass kill the offending process, setting its exit status to
* EFAULT (normally we would send the SIGSEGV signal, however
* Weenix does not support signals).
*
* Now it is time to find the correct page (don't forget
* about shadow objects, especially copy-on-write magic!). Make
* sure that if the user writes to the page it will be handled
* correctly.
*
* Finally call pt_map to have the new mapping placed into the
* appropriate page table.
*
* @param vaddr the address that was accessed to cause the fault
*
* @param cause this is the type of operation on the memory
* address which caused the fault, possible values
* can be found in pagefault.h
*/
void
handle_pagefault(uintptr_t vaddr, uint32_t cause)
{
int forwrite = 0;
if( vaddr<(USER_MEM_LOW) ||vaddr >= (USER_MEM_HIGH)){
dbg(DBG_PRINT, "(GRADING3D) ADDRESS NOT VALID \n");
do_exit(EFAULT);
return;
}
vmarea_t *container = vmmap_lookup(curproc->p_vmmap, ADDR_TO_PN(vaddr));
if(container == NULL){
dbg(DBG_PRINT, "(GRADING3D) VMAREA NOT VALID \n");
do_exit(EFAULT);
return;
}
if(container->vma_prot == PROT_NONE){
dbg(DBG_PRINT, "(GRADING3D) PROT NOT VALID \n");
do_exit(EFAULT);
return;
}
if((cause & FAULT_WRITE) && !(container->vma_prot & PROT_WRITE)){
dbg(DBG_PRINT, "(GRADING3D) CONTAINER PROT NOT VALID \n");
do_exit(EFAULT);
return;
}
if(!(container->vma_prot & PROT_READ)){
dbg(DBG_PRINT, "(GRADING3D) PROT IS NOT PROT READ \n");
do_exit(EFAULT);
return;
}
int pagenum = ADDR_TO_PN(vaddr)-container->vma_start+container->vma_off;
pframe_t *pf;
if((container->vma_prot & PROT_WRITE) && (cause & FAULT_WRITE)){
dbg(DBG_PRINT, "(GRADING3D) prot write fault write \n");
int pf_res = pframe_lookup(container->vma_obj, pagenum, 1, &pf);
if(pf_res<0){
dbg(DBG_PRINT, "(GRADING3D) pframe lookup failed\n");
do_exit(EFAULT);
}
pframe_dirty(pf);
}else{
dbg(DBG_PRINT, "(GRADING3D) prot write fault write else \n");
int pf_res = pframe_lookup(container->vma_obj, pagenum, forwrite, &pf);
if(pf_res<0){
dbg(DBG_PRINT, "(GRADING3D) pframe lookup failed \n");
do_exit(EFAULT);
}
}
KASSERT(pf);
dbg(DBG_PRINT, "(GRADING3A 5.a) pf is not NULL\n");
KASSERT(pf->pf_addr);
dbg(DBG_PRINT, "(GRADING3A 5.a) pf->addr is not NULL\n");
uint32_t pdflags = PD_PRESENT | PD_USER;
uint32_t ptflags = PT_PRESENT | PT_USER;
if(cause & FAULT_WRITE){
dbg(DBG_PRINT, "(GRADING3D) cause is fault write \n");
pdflags = pdflags | PD_WRITE;
ptflags = ptflags | PT_WRITE;
}
int ptmap_res = pt_map(curproc->p_pagedir, (uintptr_t)PAGE_ALIGN_DOWN(vaddr), pt_virt_to_phys((uintptr_t)pf->pf_addr), pdflags, ptflags);
}
/*
* This gets called by _pt_fault_handler in mm/pagetable.c The
* calling function has already done a lot of error checking for
* us. In particular it has checked that we are not page faulting
* while in kernel mode. Make sure you understand why an
* unexpected page fault in kernel mode is bad in Weenix. You
* should probably read the _pt_fault_handler function to get a
* sense of what it is doing.
*
* Before you can do anything you need to find the vmarea that
* contains the address that was faulted on. Make sure to check
* the permissions on the area to see if the process has
* permission to do [cause]. If either of these checks does not
* pass kill the offending process, setting its exit status to
* EFAULT (normally we would send the SIGSEGV signal, however
* Weenix does not support signals).
*
* Now it is time to find the correct page (don't forget
* about shadow objects, especially copy-on-write magic!). Make
* sure that if the user writes to the page it will be handled
* correctly.
*
* Finally call pt_map to have the new mapping placed into the
* appropriate page table.
*
* @param vaddr the address that was accessed to cause the fault
*
* @param cause this is the type of operation on the memory
* address which caused the fault, possible values
* can be found in pagefault.h
*/
void handle_pagefault(uintptr_t vaddr, uint32_t cause) {
/*NOT_YET_IMPLEMENTED("VM: handle_pagefault");*/
vmarea_t *vma;
pframe_t *pf;
int pflags = PD_PRESENT | PD_USER;
int writeflag = 0;
dbg(DBG_PRINT, "(GRADING3F)\n");
if ((vma = vmmap_lookup(curproc->p_vmmap, ADDR_TO_PN(vaddr))) == NULL) {
dbg(DBG_PRINT, "(GRADING3C 1)\n");
proc_kill(curproc, EFAULT);
return;
}
/*
if (vma->vma_prot & PROT_NONE) {
dbg(DBG_ERROR, "(GRADING3 3)\n");
proc_kill(curproc, EFAULT);
return;
}*/
if (!((cause & FAULT_WRITE) || (cause & FAULT_EXEC))
&& !(vma->vma_prot & PROT_READ)) {
dbg(DBG_PRINT, "(GRADING3D 3)\n");
proc_kill(curproc, EFAULT);
return;
}
if ((cause & FAULT_WRITE) && !(vma->vma_prot & PROT_WRITE)) {
dbg(DBG_PRINT, "(GRADING3D 3)\n");
proc_kill(curproc, EFAULT);
return;
}/*
if ((cause & FAULT_EXEC) && !(vma->vma_prot & PROT_EXEC)) {
dbg(DBG_ERROR, "(GRADING3 6)\n");
proc_kill(curproc, EFAULT);
return;;
}*/
if (cause & FAULT_WRITE) {
dbg(DBG_PRINT, "(GRADING3F)\n");
writeflag = 1;
}
if (pframe_lookup(vma->vma_obj,
ADDR_TO_PN(vaddr) - vma->vma_start + vma->vma_off, writeflag, &pf) < 0) {
dbg(DBG_PRINT, "(GRADING3D 4)\n");
proc_kill(curproc, EFAULT);
return;
}
if (cause & FAULT_WRITE) {
pframe_pin(pf);
dbg(DBG_PRINT, "(GRADING3F)\n");
pframe_dirty(pf);
/*
if ( < 0) {
dbg(DBG_ERROR, "(GRADING3 10)\n");
pframe_unpin(pf);
proc_kill(curproc, EFAULT);
return;
}*/
pframe_unpin(pf);
pflags |= PD_WRITE;
}
pt_map(curproc->p_pagedir, (uintptr_t) PAGE_ALIGN_DOWN(vaddr),
pt_virt_to_phys((uintptr_t) pf->pf_addr), pflags, pflags);
}
void
handle_pagefault(uintptr_t vaddr, uint32_t cause)
{
pframe_t *pf;
int ret_val;
vmarea_t *vma = vmmap_lookup(curproc->p_vmmap, ADDR_TO_PN(vaddr));
if(vma == NULL)
{
dbg(DBG_PRINT,"(GRADING3D 1): No vmarea found\n");
proc_kill(curproc,EFAULT);
return;
}
if(cause & FAULT_WRITE)
{
dbg(DBG_VM,"grade14\n");
dbg(DBG_PRINT,"(GRADING3D 1),checking permission for writing\n");
if(vma->vma_prot & PROT_WRITE)
{
dbg(DBG_VM,"grade15\n");
dbg(DBG_PRINT,"(GRADING3D 1),Vmarea has write permission\n");
ret_val = pframe_lookup(vma->vma_obj, ADDR_TO_PN(vaddr) - vma->vma_start + vma->vma_off, (cause & FAULT_WRITE),&pf);
if(ret_val<0)
{
dbg(DBG_VM,"grade16\n");
dbg(DBG_PRINT,"(GRADING3D 1),pframe could not be found\n");
proc_kill(curproc,EFAULT);
return;
}
pframe_dirty(pf);
KASSERT(pf);
dbg(DBG_PRINT,"(GRADING3A 5.a),pframe is not NULL\n");
KASSERT(pf->pf_addr);
dbg(DBG_PRINT,"(GRADING3A 5.a),pf->pf_addr is not NULL\n");
}
else
{
dbg(DBG_VM,"grade17\n");
dbg(DBG_PRINT,"(GRADING3D 1),Vmarea does not have write permission\n");
proc_kill(curproc,EFAULT);
return;
}
dbg(DBG_VM,"grade18\n");
dbg(DBG_PRINT,"(GRADING3D 1),Calling pt_map after write\n");
pt_map(curproc->p_pagedir,(uintptr_t)PAGE_ALIGN_DOWN(vaddr),pt_virt_to_phys((uintptr_t)pf->pf_addr),
(PD_WRITE|PD_PRESENT|PD_USER), (PT_WRITE|PT_PRESENT|PT_USER));
}
else
{
dbg(DBG_VM,"grade19\n");
dbg(DBG_PRINT,"(GRADING3D 1),checking permission for reading\n");
if(vma->vma_prot & PROT_READ)
{
dbg(DBG_VM,"grade20\n");
dbg(DBG_PRINT,"(GRADING3D 1),Vmarea has read permission\n");
ret_val = pframe_lookup(vma->vma_obj, ADDR_TO_PN(vaddr) - vma->vma_start + vma->vma_off, (cause & FAULT_WRITE),&pf);
if(ret_val<0)
{
dbg(DBG_VM,"grade21\n");
dbg(DBG_PRINT,"(GRADING3D 1),pframe could not be found\n");
proc_kill(curproc,EFAULT);
return;
}
dbg(DBG_VM,"grade22\n");
KASSERT(pf);
dbg(DBG_PRINT,"(GRADING3A 5.a),pframe is not NULL\n");
KASSERT(pf->pf_addr);
dbg(DBG_PRINT,"(GRADING3A 5.a),pf->pf_addr is not NULL\n");
}
else
{
dbg(DBG_VM,"grade23\n");
dbg(DBG_PRINT,"(GRADING3D 1),Vmarea does not have read permission\n");
proc_kill(curproc,EFAULT);
return;
}
dbg(DBG_VM,"grade24\n");
dbg(DBG_PRINT,"(GRADING3D 1),Calling pt_map after read\n");
pt_map(curproc->p_pagedir,(uintptr_t)PAGE_ALIGN_DOWN(vaddr),pt_virt_to_phys((uintptr_t)pf->pf_addr),
(PD_PRESENT|PD_USER), (PT_PRESENT|PT_USER));
}
}
void pmap_map(pmap_t *pmap, vm_addr_t vaddr, pm_addr_t paddr, size_t npages,
uint8_t flags) {
for (size_t i = 0; i < npages; i++)
pt_map(pmap, vaddr + i * PAGESIZE, paddr + i * PAGESIZE, flags);
}
/*
* This gets called by _pt_fault_handler in mm/pagetable.c The
* calling function has already done a lot of error checking for
* us. In particular it has checked that we are not page faulting
* while in kernel mode. Make sure you understand why an
* unexpected page fault in kernel mode is bad in Weenix. You
* should probably read the _pt_fault_handler function to get a
* sense of what it is doing.
*
* Before you can do anything you need to find the vmarea that
* contains the address that was faulted on. Make sure to check
* the permissions on the area to see if the process has
* permission to do [cause]. If either of these checks does not
* pass kill the offending process, setting its exit status to
* EFAULT (normally we would send the SIGSEGV signal, however
* Weenix does not support signals).
*
* Now it is time to find the correct page (don't forget
* about shadow objects, especially copy-on-write magic!). Make
* sure that if the user writes to the page it will be handled
* correctly.
*
* Finally call pt_map to have the new mapping placed into the
* appropriate page table.
*
* @param vaddr the address that was accessed to cause the fault
*
* @param cause this is the type of operation on the memory
* address which caused the fault, possible values
* can be found in pagefault.h
*/
void
handle_pagefault(uintptr_t vaddr, uint32_t cause)
{
/*NOT_YET_IMPLEMENTED("VM: handle_pagefault");*/
uint32_t res_vfn=ADDR_TO_PN(vaddr);
vmarea_t *temp_vmarea=vmmap_lookup(curproc->p_vmmap,res_vfn);
if(temp_vmarea==NULL)
{
proc_kill(curproc,EFAULT);
return;
}
if((cause&FAULT_PRESENT)&&(!(temp_vmarea->vma_prot&PROT_READ)))
{
proc_kill(curproc,EFAULT);
return;
}
if(cause&FAULT_RESERVED&&(!(temp_vmarea->vma_prot&PROT_NONE)))
{
proc_kill(curproc,EFAULT);
return;
}
if(cause&FAULT_EXEC&&(!(temp_vmarea->vma_prot&PROT_EXEC)))
{
proc_kill(curproc,EFAULT);
return;
}
if ((cause & FAULT_WRITE)&&!(temp_vmarea->vma_prot & PROT_WRITE))
{
do_exit(EFAULT);
return;
}
if((cause&FAULT_WRITE)==0)
{
if((temp_vmarea->vma_prot & PROT_READ)==0)
{
do_exit(EFAULT);
}
}
pframe_t *temp_pf_res=NULL;
uint32_t pagenum=temp_vmarea->vma_off+res_vfn-temp_vmarea->vma_start;
if(cause & FAULT_WRITE)/*******according to google group:1. pframe_get 2.pt_map(permission!!!)*************/
{
int tempres=pframe_lookup(temp_vmarea->vma_obj,pagenum,1, &temp_pf_res);
if(tempres<0)
{
proc_kill(curproc,EFAULT);
return;
}
uintptr_t paddr=pt_virt_to_phys((uintptr_t)temp_pf_res->pf_addr);
pt_map(curproc->p_pagedir,(uintptr_t)(PN_TO_ADDR(res_vfn)),paddr,PD_PRESENT|PD_WRITE|PD_USER,PT_PRESENT|PT_WRITE|PT_USER);
}
else{
int tempres=pframe_lookup(temp_vmarea->vma_obj,pagenum,0, &temp_pf_res);
if(tempres<0)
{
proc_kill(curproc,EFAULT);
return;
}
uintptr_t paddr=pt_virt_to_phys((uintptr_t)temp_pf_res->pf_addr);
pt_map(curproc->p_pagedir,(uintptr_t)(PN_TO_ADDR(res_vfn)),paddr,PD_PRESENT|PD_USER,PT_PRESENT|PT_USER);
}
}
