runtime.disk -> runtime.block, improved device access structure, minor fixes

Author: facekapow

js/core/disk/disk-interface.js js/core/block/block-device-interface.js

@@ -14,34 +14,33 @@
 
 'use strict';
 
-const privates = new WeakMap();
+const busHandle = Symbol('bus');
+const formatInfoHandle = Symbol('formatInfo');
 
-class DiskDriver {
-  constructor(name = '', init = {}) {
-    privates.set(this, {
-      name,
-    });
+class BlockDeviceInterface {
+  constructor(bus = '', init = {}) {
+    this[busHandle] = bus;
+    this[formatInfoHandle] = {};
     this.onread = null;
     this.onwrite = null;
-    this.ongetformatinfo = null;
     this.ongetonline = null;
-    if (typeof init === 'object') {
+    if (typeof init === 'object' && init !== null) {
       if (typeof init.read === 'function') {
         this.onread = init.read;
       }
       if (typeof init.write === 'function') {
         this.write = init.write;
       }
       if (typeof init.formatInfo === 'object') {
-        this.ongetformatinfo = () => init.formatInfo;
+        this[formatInfoHandle] = init.formatInfo;
       }
       if (typeof init.isOnline === 'function') {
         this.ongetonline = init.isOnline;
       }
     }
   }
-  get name() {
-    return privates.get(this).name;
+  get bus() {
+    return this[busHandle];
   }
   read(sector, u8) {
     if (!this.onread) {
@@ -56,10 +55,7 @@ class DiskDriver {
     return this.onwrite(sector, u8);
   }
   get formatInfo() {
-    if (!this.ongetformatinfo) {
-      throw new Error('driver was not initialized');
-    }
-    return this.ongetformatinfo();
+    return this[formatInfoHandle];
   }
   get isOnline() {
     if (!this.ongetonline) {
@@ -69,4 +65,4 @@ class DiskDriver {
   }
 }
 
-module.exports = DiskDriver;
+module.exports = BlockDeviceInterface;

js/core/disk/disks.js js/core/block/devices.js

@@ -13,15 +13,26 @@
 // limitations under the License.
 
 'use strict';
-const availableDisks = Object.create(null);
+const availableBuses = Object.create(null); // not using a Map because the buses should be easy to access directly
+const availableDevices = [];
 
 module.exports = {
-  registerDisk(disk) {
-    availableDisks[disk.name] = disk;
+  registerDevice(device) {
+    if (!availableBuses[device.bus]) availableBuses[device.bus] = [];
+    const i = availableDevices.push(device) - 1;
+    Object.assign(device, {
+      get name() {
+        return `${device.bus}${i}`;
+      },
+    });
+    availableBuses[device.bus].push(device);
 
-    console.log(`[disk] registered disk ${disk.name}`);
+    console.log(`[block] registered block device ${device.name}`);
   },
-  getDisks() {
-    return availableDisks;
+  getDevices() {
+    return availableDevices;
+  },
+  getBuses() {
+    return availableBuses;
   },
 };

js/core/disk/index.js js/core/block/index.js

@@ -13,13 +13,16 @@
 // limitations under the License.
 
 'use strict';
-const DiskInterface = require('./disk-interface');
-const { registerDisk, getDisks } = require('./disks');
+const BlockDeviceInterface = require('./block-device-interface');
+const { registerDevice, getDevices, getBuses } = require('./devices');
 
 module.exports = {
-  DiskInterface,
-  registerDisk,
-  get disks() {
-    return getDisks();
+  BlockDeviceInterface,
+  registerDevice,
+  get devices() {
+    return getDevices();
   },
+  get buses() {
+    return getBuses();
+  }
 };

js/core/index.js

@@ -18,7 +18,7 @@ const { allocator } = require('./resources');
 require('./polyfill');
 
 const random = require('./random');
-const disk = require('./disk');
+const block = require('./block');
 const keyboard = require('./keyboard');
 const ps2 = require('./ps2');
 const pci = require('./pci');
@@ -29,7 +29,7 @@ class Runtime {
   constructor() {
     Object.assign(this, {
       random,
-      disk,
+      block,
       keyboard,
       pci,
       ps2,

js/driver/virtio/blk.js

@@ -72,18 +72,16 @@ function initializeBlockDevice(pciDevice) {
     return u8;
   }
 
-  const diskDriver = new runtime.disk.DiskInterface('hda', {
+  const diskDriver = new runtime.block.BlockDeviceInterface('virtio', {
     read(sector, data) {
       return new Promise((resolve, reject) => {
         if (sector > totalSectorCount) {
-          setImmediate(() => {
-            reject(new RangeError(`sector ${sector} out of bounds (max ${totalSectorCount}, non-inclusive)`));
-          });
+          reject(new RangeError(`sector ${sector} out of bounds (max ${totalSectorCount}, non-inclusive)`));
           return;
         }
         const status = new Uint8Array(1);
         promiseQueue.push([resolve, reject, VIRTIO_BLK_T_IN, data, status]);
-        reqQueue.placeBuffers([buildHeader(VIRTIO_BLK_T_IN, sector), data, status], [false, true, true]);
+        reqQueue.placeBuffers([buildHeader(VIRTIO_BLK_T_IN, sector), data, status], null, [false, true, true]);
 
         if (reqQueue.isNotificationNeeded()) {
           dev.queueNotify(QUEUE_ID_REQ);
@@ -94,7 +92,7 @@ function initializeBlockDevice(pciDevice) {
       return new Promise((resolve, reject) => {
         const status = new Uint8Array(1);
         promiseQueue.push([resolve, reject, VIRTIO_BLK_T_OUT, data, status]);
-        reqQueue.placeBuffers([buildHeader(VIRTIO_BLK_T_OUT, sector), data, status], [false, false, true]);
+        reqQueue.placeBuffers([buildHeader(VIRTIO_BLK_T_OUT, sector), data, status], null, [false, false, true]);
 
         if (reqQueue.isNotificationNeeded()) {
           dev.queueNotify(QUEUE_ID_REQ);
@@ -111,7 +109,7 @@ function initializeBlockDevice(pciDevice) {
     },
   });
 
-  runtime.disk.registerDisk(diskDriver);
+  runtime.block.registerDevice(diskDriver);
 
   function recvBuffer() {
     if (promiseQueue.length === 0) {

js/driver/virtio/vring/descriptor-table.js

@@ -84,8 +84,9 @@ class DescriptorTable {
    * @param buffers {array} array of Uint8Array buffers
    * @param lengths {array} array of corresponding buffer lengths (same size as buffers)
    * @param isWriteOnly {bool} set writeOnly flag for each buffer
+   * @param isWriteOnlyArray {array} optional array of writeOnly flags, one value for each buffer
    */
-  placeBuffers(buffers, lengths, isWriteOnly) {
+  placeBuffers(buffers, lengths, isWriteOnly, isWriteOnlyArray) {
     const count = buffers.length;
     if (this.descriptorsAvailable < count) {
       return -1;
@@ -96,10 +97,10 @@ class DescriptorTable {
     for (let i = 0; i < count; ++i) {
       const d = buffers[i];
       let bufWriteOnly = false;
-      if (typeof isWriteOnly === 'boolean') {
-        bufWriteOnly = isWriteOnly;
+      if (isWriteOnlyArray) {
+        bufWriteOnly = isWriteOnlyArray[i];
       } else {
-        bufWriteOnly = isWriteOnly[i];
+        bufWriteOnly = isWriteOnly;
       }
       let flags = 0;
       if (count !== i + 1) {

js/driver/virtio/vring/index.js

@@ -81,8 +81,9 @@ class VRing {
    *
    * @param buffers {array} Array of buffers
    * @param isWriteOnly {bool} R/W buffers flag
+   * @param isWriteOnlyArray {array} optional array of 'isWriteOnly's, one for each buffer
    */
-  placeBuffers(buffers, isWriteOnly) {
+  placeBuffers(buffers, isWriteOnly, isWriteOnlyArray) {
     if (this.suppressInterrupts) {
       this.fetchBuffers(null);
     }
@@ -107,7 +108,7 @@ class VRing {
       }
     }
 
-    const first = this.descriptorTable.placeBuffers(pageSplitBuffers, lengths, isWriteOnly);
+    const first = this.descriptorTable.placeBuffers(pageSplitBuffers, lengths, isWriteOnly, isWriteOnlyArray);
     if (first < 0) {
       debug('virtio: no descriptors\n');
       return false;