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 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;
84 struct guest_info * vm;
87 struct virtio_blk_state {
89 struct pci_device * pci_dev;
90 struct blk_config block_cfg;
91 struct virtio_config virtio_cfg;
94 struct virtio_queue queue;
96 struct v3_dev_blk_ops * ops;
102 struct virtio_dev_state * virtio_dev;
104 struct list_head dev_link;
108 static int virtio_free(struct vm_device * dev) {
112 static int blk_reset(struct virtio_blk_state * virtio) {
114 virtio->queue.ring_desc_addr = 0;
115 virtio->queue.ring_avail_addr = 0;
116 virtio->queue.ring_used_addr = 0;
117 virtio->queue.pfn = 0;
118 virtio->queue.cur_avail_idx = 0;
120 virtio->virtio_cfg.status = 0;
121 virtio->virtio_cfg.pci_isr = 0;
126 static int virtio_reset(struct vm_device * dev) {
127 struct virtio_dev_state * dev_state = (struct virtio_dev_state *)(dev->private_data);
128 struct virtio_blk_state * blk_state = NULL;
130 list_for_each_entry(blk_state, &(dev_state->dev_list), dev_link) {
131 blk_reset(blk_state);
137 static int handle_read_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
140 PrintDebug("Reading Disk\n");
141 ret = blk_state->ops->read(buf, (*sector) * SECTOR_SIZE, len, (void *)(blk_state->backend_data));
142 *sector += (len / SECTOR_SIZE);
148 static int handle_write_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
151 PrintDebug("Writing Disk\n");
152 ret = blk_state->ops->write(buf, (*sector) * SECTOR_SIZE, len, (void *)(blk_state->backend_data));
153 *sector += (len / SECTOR_SIZE);
160 // multiple block operations need to increment the sector
162 static int handle_block_op(struct virtio_blk_state * blk_state, struct blk_op_hdr * hdr,
163 struct vring_desc * buf_desc, uint8_t * status) {
164 uint8_t * buf = NULL;
166 PrintDebug("Handling Block op\n");
167 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, buf_desc->addr_gpa, (addr_t *)&(buf)) == -1) {
168 PrintError("Could not translate buffer address\n");
172 PrintDebug("Sector=%p Length=%d\n", (void *)(addr_t)(hdr->sector), buf_desc->length);
174 if (hdr->type == BLK_IN_REQ) {
175 if (handle_read_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
176 *status = BLK_STATUS_ERR;
179 *status = BLK_STATUS_OK;
181 } else if (hdr->type == BLK_OUT_REQ) {
182 if (handle_write_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
183 *status = BLK_STATUS_ERR;
186 *status = BLK_STATUS_OK;
188 } else if (hdr->type == BLK_SCSI_CMD) {
189 PrintError("VIRTIO: SCSI Command Not supported!!!\n");
190 *status = BLK_STATUS_NOT_SUPPORTED;
194 PrintDebug("Returning Status: %d\n", *status);
199 static int get_desc_count(struct virtio_queue * q, int index) {
200 struct vring_desc * tmp_desc = &(q->desc[index]);
203 while (tmp_desc->flags & VIRTIO_NEXT_FLAG) {
204 tmp_desc = &(q->desc[tmp_desc->next]);
213 static int handle_kick(struct virtio_blk_state * blk_state) {
214 struct virtio_queue * q = &(blk_state->queue);
216 PrintDebug("VIRTIO KICK: cur_index=%d (mod=%d), avail_index=%d\n",
217 q->cur_avail_idx, q->cur_avail_idx % QUEUE_SIZE, q->avail->index);
219 while (q->cur_avail_idx < q->avail->index) {
220 struct vring_desc * hdr_desc = NULL;
221 struct vring_desc * buf_desc = NULL;
222 struct vring_desc * status_desc = NULL;
223 struct blk_op_hdr hdr;
225 uint16_t desc_idx = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
226 int desc_cnt = get_desc_count(q, desc_idx);
228 uint8_t * status_ptr = NULL;
229 uint8_t status = BLK_STATUS_OK;
230 uint32_t req_len = 0;
232 PrintDebug("Descriptor Count=%d, index=%d\n", desc_cnt, q->cur_avail_idx % QUEUE_SIZE);
235 PrintError("Block operations must include at least 3 descriptors\n");
239 hdr_desc = &(q->desc[desc_idx]);
242 PrintDebug("Header Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", hdr_desc,
243 (void *)(hdr_desc->addr_gpa), hdr_desc->length, hdr_desc->flags, hdr_desc->next);
245 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, hdr_desc->addr_gpa, &(hdr_addr)) == -1) {
246 PrintError("Could not translate block header address\n");
250 // We copy the block op header out because we are going to modify its contents
251 memcpy(&hdr, (void *)hdr_addr, sizeof(struct blk_op_hdr));
253 PrintDebug("Blk Op Hdr (ptr=%p) type=%d, sector=%p\n", (void *)hdr_addr, hdr.type, (void *)hdr.sector);
255 desc_idx = hdr_desc->next;
257 for (i = 0; i < desc_cnt - 2; i++) {
258 uint8_t tmp_status = BLK_STATUS_OK;
260 buf_desc = &(q->desc[desc_idx]);
262 PrintDebug("Buffer Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", buf_desc,
263 (void *)(buf_desc->addr_gpa), buf_desc->length, buf_desc->flags, buf_desc->next);
265 if (handle_block_op(blk_state, &hdr, buf_desc, &tmp_status) == -1) {
266 PrintError("Error handling block operation\n");
270 if (tmp_status != BLK_STATUS_OK) {
274 req_len += buf_desc->length;
275 desc_idx = buf_desc->next;
278 status_desc = &(q->desc[desc_idx]);
280 PrintDebug("Status Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", status_desc,
281 (void *)(status_desc->addr_gpa), status_desc->length, status_desc->flags, status_desc->next);
283 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, status_desc->addr_gpa, (addr_t *)&(status_ptr)) == -1) {
284 PrintError("Could not translate status address\n");
288 req_len += status_desc->length;
289 *status_ptr = status;
291 q->used->ring[q->used->index % QUEUE_SIZE].id = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
292 q->used->ring[q->used->index % QUEUE_SIZE].length = req_len; // What do we set this to????
298 if (!(q->avail->flags & VIRTIO_NO_IRQ_FLAG)) {
299 PrintDebug("Raising IRQ %d\n", blk_state->pci_dev->config_header.intr_line);
300 v3_pci_raise_irq(blk_state->virtio_dev->pci_bus, 0, blk_state->pci_dev);
301 blk_state->virtio_cfg.pci_isr = 1;
307 static int virtio_io_write(uint16_t port, void * src, uint_t length, void * private_data) {
308 struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
309 int port_idx = port % blk_state->io_range_size;
312 PrintDebug("VIRTIO BLOCK Write for port %d (index=%d) len=%d, value=%x\n",
313 port, port_idx, length, *(uint32_t *)src);
318 case GUEST_FEATURES_PORT:
320 PrintError("Illegal write length for guest features\n");
324 blk_state->virtio_cfg.guest_features = *(uint32_t *)src;
325 PrintDebug("Setting Guest Features to %x\n", blk_state->virtio_cfg.guest_features);
328 case VRING_PG_NUM_PORT:
330 addr_t pfn = *(uint32_t *)src;
331 addr_t page_addr = (pfn << VIRTIO_PAGE_SHIFT);
334 blk_state->queue.pfn = pfn;
336 blk_state->queue.ring_desc_addr = page_addr ;
337 blk_state->queue.ring_avail_addr = page_addr + (QUEUE_SIZE * sizeof(struct vring_desc));
338 blk_state->queue.ring_used_addr = ( blk_state->queue.ring_avail_addr + \
339 sizeof(struct vring_avail) + \
340 (QUEUE_SIZE * sizeof(uint16_t)));
342 // round up to next page boundary.
343 blk_state->queue.ring_used_addr = (blk_state->queue.ring_used_addr + 0xfff) & ~0xfff;
345 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_desc_addr, (addr_t *)&(blk_state->queue.desc)) == -1) {
346 PrintError("Could not translate ring descriptor address\n");
351 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_avail_addr, (addr_t *)&(blk_state->queue.avail)) == -1) {
352 PrintError("Could not translate ring available address\n");
357 if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_used_addr, (addr_t *)&(blk_state->queue.used)) == -1) {
358 PrintError("Could not translate ring used address\n");
362 PrintDebug("RingDesc_addr=%p, Avail_addr=%p, Used_addr=%p\n",
363 (void *)(blk_state->queue.ring_desc_addr),
364 (void *)(blk_state->queue.ring_avail_addr),
365 (void *)(blk_state->queue.ring_used_addr));
367 PrintDebug("RingDesc=%p, Avail=%p, Used=%p\n",
368 blk_state->queue.desc, blk_state->queue.avail, blk_state->queue.used);
371 PrintError("Illegal write length for page frame number\n");
375 case VRING_Q_SEL_PORT:
376 blk_state->virtio_cfg.vring_queue_selector = *(uint16_t *)src;
378 if (blk_state->virtio_cfg.vring_queue_selector != 0) {
379 PrintError("Virtio Block device only uses 1 queue, selected %d\n",
380 blk_state->virtio_cfg.vring_queue_selector);
385 case VRING_Q_NOTIFY_PORT:
386 PrintDebug("Handling Kick\n");
387 if (handle_kick(blk_state) == -1) {
388 PrintError("Could not handle Block Notification\n");
392 case VIRTIO_STATUS_PORT:
393 blk_state->virtio_cfg.status = *(uint8_t *)src;
395 if (blk_state->virtio_cfg.status == 0) {
396 PrintDebug("Resetting device\n");
397 blk_reset(blk_state);
402 case VIRTIO_ISR_PORT:
403 blk_state->virtio_cfg.pci_isr = *(uint8_t *)src;
414 static int virtio_io_read(uint16_t port, void * dst, uint_t length, void * private_data) {
415 struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
416 int port_idx = port % blk_state->io_range_size;
419 PrintDebug("VIRTIO BLOCK Read for port %d (index =%d), length=%d\n",
420 port, port_idx, length);
423 case HOST_FEATURES_PORT:
425 PrintError("Illegal read length for host features\n");
429 *(uint32_t *)dst = blk_state->virtio_cfg.host_features;
432 case VRING_PG_NUM_PORT:
434 PrintError("Illegal read length for page frame number\n");
438 *(uint32_t *)dst = blk_state->queue.pfn;
441 case VRING_SIZE_PORT:
443 PrintError("Illegal read length for vring size\n");
447 *(uint16_t *)dst = blk_state->queue.queue_size;
451 case VIRTIO_STATUS_PORT:
453 PrintError("Illegal read length for status\n");
457 *(uint8_t *)dst = blk_state->virtio_cfg.status;
460 case VIRTIO_ISR_PORT:
461 *(uint8_t *)dst = blk_state->virtio_cfg.pci_isr;
462 blk_state->virtio_cfg.pci_isr = 0;
463 v3_pci_lower_irq(blk_state->virtio_dev->pci_bus, 0, blk_state->pci_dev);
467 if ( (port_idx >= sizeof(struct virtio_config)) &&
468 (port_idx < (sizeof(struct virtio_config) + sizeof(struct blk_config))) ) {
469 int cfg_offset = port_idx - sizeof(struct virtio_config);
470 uint8_t * cfg_ptr = (uint8_t *)&(blk_state->block_cfg);
472 memcpy(dst, cfg_ptr + cfg_offset, length);
475 PrintError("Read of Unhandled Virtio Read\n");
488 static struct v3_device_ops dev_ops = {
490 .reset = virtio_reset,
499 static int register_dev(struct virtio_dev_state * virtio, struct virtio_blk_state * blk_state) {
501 struct pci_device * pci_dev = NULL;
502 struct v3_pci_bar bars[6];
503 int num_ports = sizeof(struct virtio_config) + sizeof(struct blk_config);
504 int tmp_ports = num_ports;
509 // This gets the number of ports, rounded up to a power of 2
510 blk_state->io_range_size = 1; // must be a power of 2
512 while (tmp_ports > 0) {
514 blk_state->io_range_size <<= 1;
517 // this is to account for any low order bits being set in num_ports
518 // if there are none, then num_ports was already a power of 2 so we shift right to reset it
519 if ((num_ports & ((blk_state->io_range_size >> 1) - 1)) == 0) {
520 blk_state->io_range_size >>= 1;
524 for (i = 0; i < 6; i++) {
525 bars[i].type = PCI_BAR_NONE;
528 PrintDebug("Virtio-BLK io_range_size = %d\n", blk_state->io_range_size);
530 bars[0].type = PCI_BAR_IO;
531 bars[0].default_base_port = -1;
532 bars[0].num_ports = blk_state->io_range_size;
534 bars[0].io_read = virtio_io_read;
535 bars[0].io_write = virtio_io_write;
536 bars[0].private_data = blk_state;
538 pci_dev = v3_pci_register_device(virtio->pci_bus, PCI_STD_DEVICE,
539 0, PCI_AUTO_DEV_NUM, 0,
540 "LNX_VIRTIO_BLK", bars,
541 NULL, NULL, NULL, blk_state);
544 PrintError("Could not register PCI Device\n");
548 pci_dev->config_header.vendor_id = VIRTIO_VENDOR_ID;
549 pci_dev->config_header.subsystem_vendor_id = VIRTIO_SUBVENDOR_ID;
552 pci_dev->config_header.device_id = VIRTIO_BLOCK_DEV_ID;
553 pci_dev->config_header.class = PCI_CLASS_STORAGE;
554 pci_dev->config_header.subclass = PCI_STORAGE_SUBCLASS_OTHER;
556 pci_dev->config_header.subsystem_id = VIRTIO_BLOCK_SUBDEVICE_ID;
559 pci_dev->config_header.intr_pin = 1;
561 pci_dev->config_header.max_latency = 1; // ?? (qemu does it...)
564 blk_state->pci_dev = pci_dev;
566 /* Block configuration */
567 blk_state->virtio_cfg.host_features = VIRTIO_SEG_MAX;
568 blk_state->block_cfg.max_seg = QUEUE_SIZE - 2;
570 // Virtio Block only uses one queue
571 blk_state->queue.queue_size = QUEUE_SIZE;
573 blk_state->virtio_dev = virtio;
575 blk_reset(blk_state);
582 static int connect_fn(struct guest_info * info,
583 void * frontend_data,
584 struct v3_dev_blk_ops * ops,
586 void * private_data) {
588 struct virtio_dev_state * virtio = (struct virtio_dev_state *)frontend_data;
590 struct virtio_blk_state * blk_state = (struct virtio_blk_state *)V3_Malloc(sizeof(struct virtio_blk_state));
591 memset(blk_state, 0, sizeof(struct virtio_blk_state));
593 register_dev(virtio, blk_state);
595 blk_state->ops = ops;
596 blk_state->backend_data = private_data;
598 blk_state->block_cfg.capacity = ops->get_capacity(private_data) / SECTOR_SIZE;
600 PrintDebug("Virtio Capacity = %d -- 0x%p\n", (int)(blk_state->block_cfg.capacity),
601 (void *)(addr_t)(blk_state->block_cfg.capacity));
607 static int virtio_init(struct guest_info * vm, v3_cfg_tree_t * cfg) {
608 struct vm_device * pci_bus = v3_find_dev(vm, v3_cfg_val(cfg, "bus"));
609 struct virtio_dev_state * virtio_state = NULL;
610 char * name = v3_cfg_val(cfg, "name");
612 PrintDebug("Initializing VIRTIO Block device\n");
614 if (pci_bus == NULL) {
615 PrintError("VirtIO devices require a PCI Bus");
620 virtio_state = (struct virtio_dev_state *)V3_Malloc(sizeof(struct virtio_dev_state));
621 memset(virtio_state, 0, sizeof(struct virtio_dev_state));
623 INIT_LIST_HEAD(&(virtio_state->dev_list));
624 virtio_state->pci_bus = pci_bus;
625 virtio_state->vm = vm;
627 struct vm_device * dev = v3_allocate_device(name, &dev_ops, virtio_state);
628 if (v3_attach_device(vm, dev) == -1) {
629 PrintError("Could not attach device %s\n", name);
633 if (v3_dev_add_blk_frontend(vm, name, connect_fn, (void *)virtio_state) == -1) {
634 PrintError("Could not register %s as block frontend\n", name);
642 device_register("LNX_VIRTIO_BLK", virtio_init)