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More PAGEBLOCKS support

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Jeff Parsons 2015-04-29 09:45:03 -07:00 • committed by jeffpar
commit 453d84c6d8
7 changed files with 252 additions and 48 deletions
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64
modules/pcjs/lib/bus.js
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@ -39,6 +39,7 @@ if (typeof module !== 'undefined') {
var Memory = require("./memory");
var Messages = require("./messages");
var State = require("./state");
var X86 = require("./x86");
}
/**
@ -67,8 +68,8 @@ if (typeof module !== 'undefined') {
* @constructor
* @extends Component
* @param {Object} parmsBus
* @param {X86CPU|Component} cpu
* @param {Debugger|Component} dbg
* @param {X86CPU} cpu
* @param {Debugger} dbg
*/
function Bus(parmsBus, cpu, dbg)
{
@ -689,20 +690,59 @@ Bus.prototype.enablePageBlocks = function(addrPD)
};
/**
* mapPageBlock(addr)
* mapPageBlock(addr, fWrite)
*
* If addr is a valid linear address, then we must obtain the following information:
* Locate the corresponding physical PDE, PTE and memory blocks for the given linear address.
*
* (1) the physical Memory object corresponding to the linear address in addr
* (2) the physical Memory object containing that memory's PTE
* (3) the offset within the preceding physical Memory object of that memory's PTE
*
* Item (1) allows us to convert an "unpaged" Memory block in to a "paged" Memory block, and the combination of
* (2) and (3) allows us to efficiently update the PTE whenever the page is accesssed and/or modified.
* @this {Bus}
* @param {number} addr is a linear address
* @param {boolean} fWrite (true if called for a write, false if for a read)
* @return {Memory|null}
*/
Bus.prototype.mapPageBlock = function(addr)
Bus.prototype.mapPageBlock = function(addr, fWrite)
{
return null;
var offPDE = (addr & X86.LADDR.PDE.MASK) >>> X86.LADDR.PDE.SHIFT;
var addrPDE = this.cpu.regCR3 + offPDE; // TODO: adding offPDE could be eliminated, along with the busMask mask
var blockPDE = this.aPhysBlocks[(addrPDE & this.busMask) >>> this.blockShift];
var pde = blockPDE.readLong(offPDE);
if (!(pde & X86.PTE.PRESENT)) {
X86.fnPageFault.call(this.cpu, addr, false, fWrite);
return null;
}
if (!(pde & X86.PTE.USER) && this.cpu.segCS.cpl == 3) {
X86.fnPageFault.call(this.cpu, addr, true, fWrite);
return null;
}
var offPTE = (addr & X86.LADDR.PTE.MASK) >>> X86.LADDR.PTE.SHIFT;
var addrPTE = (pde & X86.PTE.FRAME) + offPTE; // TODO: adding offPTE could be eliminated, along with the busMask mask
var blockPTE = this.aPhysBlocks[(addrPTE & this.busMask) >>> this.blockShift];
var pte = blockPTE.readLong(offPTE);
if (!(pte & X86.PTE.PRESENT)) {
X86.fnPageFault.call(this.cpu, addr, false, fWrite);
return null;
}
if (!(pte & X86.PTE.USER) && this.cpu.segCS.cpl == 3) {
X86.fnPageFault.call(this.cpu, addr, true, fWrite);
return null;
}
var addrPhys = (pte & X86.PTE.FRAME) + (addr & X86.LADDR.OFFSET); // TODO: Adding OFFSET could be eliminated, along with the busMask mask
var blockPhys = this.aPhysBlocks[(addrPhys & this.busMask) >>> this.blockShift];
/*
* So we have the block containing the physical memory corresponding to the given linear address.
*
* Now we create a new "paged" Memory block and record the physical block info using setPhysBlock().
*/
var addrPage = addr & ~X86.LADDR.OFFSET;
var blockPage = new Memory(addrPage, 0, this.blockSize, Memory.TYPE.PAGED);
blockPage.setPhysBlock(blockPage, blockPDE, offPDE, blockPTE, offPTE);
return blockPage;
};
/**