2 * This file is part of the Palacios Virtual Machine Monitor developed
3 * by the V3VEE Project with funding from the United States National
4 * Science Foundation and the Department of Energy.
6 * The V3VEE Project is a joint project between Northwestern University
7 * and the University of New Mexico. You can find out more at
10 * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
11 * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
12 * All rights reserved.
14 * Author: Jack Lange <jarusl@cs.northwestern.edu>
16 * This is free software. You are permitted to use,
17 * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
20 #include <palacios/vmm.h>
21 #include <palacios/vmm_dev_mgr.h>
22 #include <devices/lnx_virtio_pci.h>
23 #include <palacios/vm_guest_mem.h>
25 #include <devices/pci.h>
29 #ifndef V3_CONFIG_DEBUG_VIRTIO_BLK
31 #define PrintDebug(fmt, args...)
35 #define SECTOR_SIZE 512
37 #define BLK_CAPACITY_PORT 20
38 #define BLK_MAX_SIZE_PORT 28
39 #define BLK_MAX_SEG_PORT 32
40 #define BLK_CYLINDERS_PORT 36
41 #define BLK_HEADS_PORT 38
42 #define BLK_SECTS_PORT 39
46 #define BLK_SCSI_CMD 2
48 #define BLK_BARRIER_FLAG 0x80000000
50 #define BLK_STATUS_OK 0
51 #define BLK_STATUS_ERR 1
52 #define BLK_STATUS_NOT_SUPPORTED 2
62 } __attribute__((packed));
70 } __attribute__((packed));
72 #define QUEUE_SIZE 128
74 /* Host Feature flags */
75 #define VIRTIO_BARRIER 0x01 /* Does host support barriers? */
76 #define VIRTIO_SIZE_MAX 0x02 /* Indicates maximum segment size */
77 #define VIRTIO_SEG_MAX 0x04 /* Indicates maximum # of segments */
78 #define VIRTIO_LEGACY_GEOM 0x10 /* Indicates support of legacy geometry */
81 struct virtio_dev_state {
82 struct vm_device * pci_bus;
83 struct list_head dev_list;
86 struct virtio_blk_state {
88 struct pci_device * pci_dev;
89 struct blk_config block_cfg;
90 struct virtio_config virtio_cfg;
93 struct virtio_queue queue;
95 struct v3_dev_blk_ops * ops;
101 struct virtio_dev_state * virtio_dev;
103 struct list_head dev_link;
109 static int blk_reset(struct virtio_blk_state * virtio) {
111 virtio->queue.ring_desc_addr = 0;
112 virtio->queue.ring_avail_addr = 0;
113 virtio->queue.ring_used_addr = 0;
114 virtio->queue.pfn = 0;
115 virtio->queue.cur_avail_idx = 0;
117 virtio->virtio_cfg.status = 0;
118 virtio->virtio_cfg.pci_isr = 0;
125 static int handle_read_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
128 PrintDebug(info->vm_info, info, "Reading Disk\n");
129 ret = blk_state->ops->read(buf, (*sector) * SECTOR_SIZE, len, (void *)(blk_state->backend_data));
130 *sector += (len / SECTOR_SIZE);
136 static int handle_write_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
139 PrintDebug(info->vm_info, info, "Writing Disk\n");
140 ret = blk_state->ops->write(buf, (*sector) * SECTOR_SIZE, len, (void *)(blk_state->backend_data));
141 *sector += (len / SECTOR_SIZE);
148 // multiple block operations need to increment the sector
150 static int handle_block_op(struct guest_info * core, struct virtio_blk_state * blk_state, struct blk_op_hdr * hdr,
151 struct vring_desc * buf_desc, uint8_t * status) {
152 uint8_t * buf = NULL;
154 PrintDebug(core->vm_info, core, "Handling Block op\n");
155 if (v3_gpa_to_hva(core, buf_desc->addr_gpa, (addr_t *)&(buf)) == -1) {
156 PrintError(core->vm_info, core, "Could not translate buffer address\n");
160 PrintDebug(core->vm_info, core, "Sector=%p Length=%d\n", (void *)(addr_t)(hdr->sector), buf_desc->length);
162 if (hdr->type == BLK_IN_REQ) {
163 if (handle_read_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
164 *status = BLK_STATUS_ERR;
167 *status = BLK_STATUS_OK;
169 } else if (hdr->type == BLK_OUT_REQ) {
170 if (handle_write_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
171 *status = BLK_STATUS_ERR;
174 *status = BLK_STATUS_OK;
176 } else if (hdr->type == BLK_SCSI_CMD) {
177 PrintError(core->vm_info, core, "VIRTIO: SCSI Command Not supported!!!\n");
178 *status = BLK_STATUS_NOT_SUPPORTED;
182 PrintDebug(core->vm_info, core, "Returning Status: %d\n", *status);
187 static int get_desc_count(struct virtio_queue * q, int index) {
188 struct vring_desc * tmp_desc = &(q->desc[index]);
191 while (tmp_desc->flags & VIRTIO_NEXT_FLAG) {
192 tmp_desc = &(q->desc[tmp_desc->next]);
201 static int handle_kick(struct guest_info * core, struct virtio_blk_state * blk_state) {
202 struct virtio_queue * q = &(blk_state->queue);
204 PrintDebug(core->vm_info, core, "VIRTIO KICK: cur_index=%d (mod=%d), avail_index=%d\n",
205 q->cur_avail_idx, q->cur_avail_idx % QUEUE_SIZE, q->avail->index);
207 while (q->cur_avail_idx != q->avail->index) {
208 struct vring_desc * hdr_desc = NULL;
209 struct vring_desc * buf_desc = NULL;
210 struct vring_desc * status_desc = NULL;
211 struct blk_op_hdr hdr;
213 uint16_t desc_idx = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
214 int desc_cnt = get_desc_count(q, desc_idx);
216 uint8_t * status_ptr = NULL;
217 uint8_t status = BLK_STATUS_OK;
218 uint32_t req_len = 0;
220 PrintDebug(core->vm_info, core, "Descriptor Count=%d, index=%d\n", desc_cnt, q->cur_avail_idx % QUEUE_SIZE);
223 PrintError(core->vm_info, core, "Block operations must include at least 3 descriptors\n");
227 hdr_desc = &(q->desc[desc_idx]);
230 PrintDebug(core->vm_info, core, "Header Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", hdr_desc,
231 (void *)(hdr_desc->addr_gpa), hdr_desc->length, hdr_desc->flags, hdr_desc->next);
233 if (v3_gpa_to_hva(core, hdr_desc->addr_gpa, &(hdr_addr)) == -1) {
234 PrintError(core->vm_info, core, "Could not translate block header address\n");
238 // We copy the block op header out because we are going to modify its contents
239 memcpy(&hdr, (void *)hdr_addr, sizeof(struct blk_op_hdr));
241 PrintDebug(core->vm_info, core, "Blk Op Hdr (ptr=%p) type=%d, sector=%p\n", (void *)hdr_addr, hdr.type, (void *)hdr.sector);
243 desc_idx = hdr_desc->next;
245 for (i = 0; i < desc_cnt - 2; i++) {
246 uint8_t tmp_status = BLK_STATUS_OK;
248 buf_desc = &(q->desc[desc_idx]);
250 PrintDebug(core->vm_info, core, "Buffer Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", buf_desc,
251 (void *)(buf_desc->addr_gpa), buf_desc->length, buf_desc->flags, buf_desc->next);
253 if (handle_block_op(core, blk_state, &hdr, buf_desc, &tmp_status) == -1) {
254 PrintError(core->vm_info, core, "Error handling block operation\n");
258 if (tmp_status != BLK_STATUS_OK) {
262 req_len += buf_desc->length;
263 desc_idx = buf_desc->next;
266 status_desc = &(q->desc[desc_idx]);
268 PrintDebug(core->vm_info, core, "Status Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", status_desc,
269 (void *)(status_desc->addr_gpa), status_desc->length, status_desc->flags, status_desc->next);
271 if (v3_gpa_to_hva(core, status_desc->addr_gpa, (addr_t *)&(status_ptr)) == -1) {
272 PrintError(core->vm_info, core, "Could not translate status address\n");
276 req_len += status_desc->length;
277 *status_ptr = status;
279 q->used->ring[q->used->index % QUEUE_SIZE].id = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
280 q->used->ring[q->used->index % QUEUE_SIZE].length = req_len; // What do we set this to????
286 if (!(q->avail->flags & VIRTIO_NO_IRQ_FLAG)) {
287 PrintDebug(core->vm_info, core, "Raising IRQ %d\n", blk_state->pci_dev->config_header.intr_line);
288 v3_pci_raise_irq(blk_state->virtio_dev->pci_bus, blk_state->pci_dev, 0);
289 blk_state->virtio_cfg.pci_isr = 1;
295 static int virtio_io_write(struct guest_info * core, uint16_t port, void * src, uint_t length, void * private_data) {
296 struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
297 int port_idx = port % blk_state->io_range_size;
300 PrintDebug(core->vm_info, core, "VIRTIO BLOCK Write for port %d (index=%d) len=%d, value=%x\n",
301 port, port_idx, length, *(uint32_t *)src);
306 case GUEST_FEATURES_PORT:
308 PrintError(core->vm_info, core, "Illegal write length for guest features\n");
312 blk_state->virtio_cfg.guest_features = *(uint32_t *)src;
313 PrintDebug(core->vm_info, core, "Setting Guest Features to %x\n", blk_state->virtio_cfg.guest_features);
316 case VRING_PG_NUM_PORT:
318 addr_t pfn = *(uint32_t *)src;
319 addr_t page_addr = (pfn << VIRTIO_PAGE_SHIFT);
322 blk_state->queue.pfn = pfn;
324 blk_state->queue.ring_desc_addr = page_addr ;
325 blk_state->queue.ring_avail_addr = page_addr + (QUEUE_SIZE * sizeof(struct vring_desc));
326 blk_state->queue.ring_used_addr = ( blk_state->queue.ring_avail_addr + \
327 sizeof(struct vring_avail) + \
328 (QUEUE_SIZE * sizeof(uint16_t)));
330 // round up to next page boundary.
331 blk_state->queue.ring_used_addr = (blk_state->queue.ring_used_addr + 0xfff) & ~0xfff;
333 if (v3_gpa_to_hva(core, blk_state->queue.ring_desc_addr, (addr_t *)&(blk_state->queue.desc)) == -1) {
334 PrintError(core->vm_info, core, "Could not translate ring descriptor address\n");
339 if (v3_gpa_to_hva(core, blk_state->queue.ring_avail_addr, (addr_t *)&(blk_state->queue.avail)) == -1) {
340 PrintError(core->vm_info, core, "Could not translate ring available address\n");
345 if (v3_gpa_to_hva(core, blk_state->queue.ring_used_addr, (addr_t *)&(blk_state->queue.used)) == -1) {
346 PrintError(core->vm_info, core, "Could not translate ring used address\n");
350 PrintDebug(core->vm_info, core, "RingDesc_addr=%p, Avail_addr=%p, Used_addr=%p\n",
351 (void *)(blk_state->queue.ring_desc_addr),
352 (void *)(blk_state->queue.ring_avail_addr),
353 (void *)(blk_state->queue.ring_used_addr));
355 PrintDebug(core->vm_info, core, "RingDesc=%p, Avail=%p, Used=%p\n",
356 blk_state->queue.desc, blk_state->queue.avail, blk_state->queue.used);
359 PrintError(core->vm_info, core, "Illegal write length for page frame number\n");
363 case VRING_Q_SEL_PORT:
364 blk_state->virtio_cfg.vring_queue_selector = *(uint16_t *)src;
366 if (blk_state->virtio_cfg.vring_queue_selector != 0) {
367 PrintError(core->vm_info, core, "Virtio Block device only uses 1 queue, selected %d\n",
368 blk_state->virtio_cfg.vring_queue_selector);
373 case VRING_Q_NOTIFY_PORT:
374 PrintDebug(core->vm_info, core, "Handling Kick\n");
375 if (handle_kick(core, blk_state) == -1) {
376 PrintError(core->vm_info, core, "Could not handle Block Notification\n");
380 case VIRTIO_STATUS_PORT:
381 blk_state->virtio_cfg.status = *(uint8_t *)src;
383 if (blk_state->virtio_cfg.status == 0) {
384 PrintDebug(core->vm_info, core, "Resetting device\n");
385 blk_reset(blk_state);
390 case VIRTIO_ISR_PORT:
391 blk_state->virtio_cfg.pci_isr = *(uint8_t *)src;
402 static int virtio_io_read(struct guest_info * core, uint16_t port, void * dst, uint_t length, void * private_data) {
403 struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
404 int port_idx = port % blk_state->io_range_size;
407 PrintDebug(core->vm_info, core, "VIRTIO BLOCK Read for port %d (index =%d), length=%d\n",
408 port, port_idx, length);
412 case HOST_FEATURES_PORT:
413 case HOST_FEATURES_PORT + 1:
414 case HOST_FEATURES_PORT + 2:
415 case HOST_FEATURES_PORT + 3:
416 if (port_idx + length > HOST_FEATURES_PORT + 4) {
417 PrintError(core->vm_info, core, "Illegal read length for host features (len=%d)\n", length);
421 memcpy(dst, &(blk_state->virtio_cfg.host_features), length);
423 case VRING_PG_NUM_PORT:
424 case VRING_PG_NUM_PORT + 1:
425 case VRING_PG_NUM_PORT + 2:
426 case VRING_PG_NUM_PORT + 3:
427 if (port_idx + length > VRING_PG_NUM_PORT + 4) {
428 PrintError(core->vm_info, core, "Illegal read length for vring pg num (len=%d)\n", length);
432 memcpy(dst, &(blk_state->queue.pfn), length);
434 case VRING_SIZE_PORT:
435 case VRING_SIZE_PORT + 1:
437 PrintError(core->vm_info, core, "Illegal read length for vring size (len=%d)\n", length);
441 memcpy(dst, &(blk_state->queue.queue_size), length);
445 case VIRTIO_STATUS_PORT:
447 PrintError(core->vm_info, core, "Illegal read length for status (len=%d)\n", length);
451 *(uint8_t *)dst = blk_state->virtio_cfg.status;
454 case VIRTIO_ISR_PORT:
455 *(uint8_t *)dst = blk_state->virtio_cfg.pci_isr;
456 blk_state->virtio_cfg.pci_isr = 0;
457 v3_pci_lower_irq(blk_state->virtio_dev->pci_bus, blk_state->pci_dev, 0);
461 if ( (port_idx >= sizeof(struct virtio_config)) &&
462 (port_idx < (sizeof(struct virtio_config) + sizeof(struct blk_config))) ) {
463 int cfg_offset = port_idx - sizeof(struct virtio_config);
464 uint8_t * cfg_ptr = (uint8_t *)&(blk_state->block_cfg);
466 memcpy(dst, cfg_ptr + cfg_offset, length);
469 PrintError(core->vm_info, core, "Read of Unhandled Virtio Read\n");
480 static int virtio_free(struct virtio_dev_state * virtio) {
481 struct virtio_blk_state * blk_state = NULL;
482 struct virtio_blk_state * tmp = NULL;
484 list_for_each_entry_safe(blk_state, tmp, &(virtio->dev_list), dev_link) {
486 // unregister from PCI
488 list_del(&(blk_state->dev_link));
500 static struct v3_device_ops dev_ops = {
501 .free = (int (*)(void *))virtio_free,
509 static int register_dev(struct virtio_dev_state * virtio, struct virtio_blk_state * blk_state) {
511 struct pci_device * pci_dev = NULL;
512 struct v3_pci_bar bars[6];
513 int num_ports = sizeof(struct virtio_config) + sizeof(struct blk_config);
514 int tmp_ports = num_ports;
519 // This gets the number of ports, rounded up to a power of 2
520 blk_state->io_range_size = 1; // must be a power of 2
522 while (tmp_ports > 0) {
524 blk_state->io_range_size <<= 1;
527 // this is to account for any low order bits being set in num_ports
528 // if there are none, then num_ports was already a power of 2 so we shift right to reset it
529 if ((num_ports & ((blk_state->io_range_size >> 1) - 1)) == 0) {
530 blk_state->io_range_size >>= 1;
534 for (i = 0; i < 6; i++) {
535 bars[i].type = PCI_BAR_NONE;
538 PrintDebug(VM_NONE, VCORE_NONE, "Virtio-BLK io_range_size = %d\n", blk_state->io_range_size);
540 bars[0].type = PCI_BAR_IO;
541 bars[0].default_base_port = -1;
542 bars[0].num_ports = blk_state->io_range_size;
544 bars[0].io_read = virtio_io_read;
545 bars[0].io_write = virtio_io_write;
546 bars[0].private_data = blk_state;
548 pci_dev = v3_pci_register_device(virtio->pci_bus, PCI_STD_DEVICE,
549 0, PCI_AUTO_DEV_NUM, 0,
550 "LNX_VIRTIO_BLK", bars,
551 NULL, NULL, NULL, NULL, blk_state);
554 PrintError(VM_NONE, VCORE_NONE, "Could not register PCI Device\n");
558 pci_dev->config_header.vendor_id = VIRTIO_VENDOR_ID;
559 pci_dev->config_header.subsystem_vendor_id = VIRTIO_SUBVENDOR_ID;
562 pci_dev->config_header.device_id = VIRTIO_BLOCK_DEV_ID;
563 pci_dev->config_header.class = PCI_CLASS_STORAGE;
564 pci_dev->config_header.subclass = PCI_STORAGE_SUBCLASS_OTHER;
566 pci_dev->config_header.subsystem_id = VIRTIO_BLOCK_SUBDEVICE_ID;
569 pci_dev->config_header.intr_pin = 1;
571 pci_dev->config_header.max_latency = 1; // ?? (qemu does it...)
574 blk_state->pci_dev = pci_dev;
577 /* Add backend to list of devices */
578 list_add(&(blk_state->dev_link), &(virtio->dev_list));
580 /* Block configuration */
581 blk_state->virtio_cfg.host_features = VIRTIO_SEG_MAX;
582 blk_state->block_cfg.max_seg = QUEUE_SIZE - 2;
584 // Virtio Block only uses one queue
585 blk_state->queue.queue_size = QUEUE_SIZE;
587 blk_state->virtio_dev = virtio;
589 blk_reset(blk_state);
596 static int connect_fn(struct v3_vm_info * vm,
597 void * frontend_data,
598 struct v3_dev_blk_ops * ops,
600 void * private_data) {
602 struct virtio_dev_state * virtio = (struct virtio_dev_state *)frontend_data;
604 struct virtio_blk_state * blk_state = (struct virtio_blk_state *)V3_Malloc(sizeof(struct virtio_blk_state));
607 PrintError(vm, VCORE_NONE, "Cannot allocate in connect\n");
612 memset(blk_state, 0, sizeof(struct virtio_blk_state));
614 register_dev(virtio, blk_state);
616 blk_state->ops = ops;
617 blk_state->backend_data = private_data;
619 blk_state->block_cfg.capacity = ops->get_capacity(private_data) / SECTOR_SIZE;
621 PrintDebug(vm, VCORE_NONE, "Virtio Capacity = %d -- 0x%p\n", (int)(blk_state->block_cfg.capacity),
622 (void *)(addr_t)(blk_state->block_cfg.capacity));
628 static int virtio_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
629 struct vm_device * pci_bus = v3_find_dev(vm, v3_cfg_val(cfg, "bus"));
630 struct virtio_dev_state * virtio_state = NULL;
631 char * dev_id = v3_cfg_val(cfg, "ID");
633 PrintDebug(vm, VCORE_NONE, "Initializing VIRTIO Block device\n");
635 if (pci_bus == NULL) {
636 PrintError(vm, VCORE_NONE, "VirtIO devices require a PCI Bus");
641 virtio_state = (struct virtio_dev_state *)V3_Malloc(sizeof(struct virtio_dev_state));
644 PrintError(vm, VCORE_NONE, "Cannot allocate in init\n");
648 memset(virtio_state, 0, sizeof(struct virtio_dev_state));
650 INIT_LIST_HEAD(&(virtio_state->dev_list));
651 virtio_state->pci_bus = pci_bus;
654 struct vm_device * dev = v3_add_device(vm, dev_id, &dev_ops, virtio_state);
657 PrintError(vm, VCORE_NONE, "Could not attach device %s\n", dev_id);
658 V3_Free(virtio_state);
662 if (v3_dev_add_blk_frontend(vm, dev_id, connect_fn, (void *)virtio_state) == -1) {
663 PrintError(vm, VCORE_NONE, "Could not register %s as block frontend\n", dev_id);
664 v3_remove_device(dev);
672 device_register("LNX_VIRTIO_BLK", virtio_init)