X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?p=palacios.git;a=blobdiff_plain;f=palacios%2Fsrc%2Fdevices%2Flnx_virtio_blk.c;h=7bc41a63209e28f73a0242bf5aa02f5c9f0daf0a;hp=787d965aa883efe0487418e3f5580b7d8d1875d7;hb=123a1ba27ea09c8fa77a1b36ce625b43d7c48b14;hpb=be25a0dd3f691dbef727998ab27910df9fa95e51

diff --git a/palacios/src/devices/lnx_virtio_blk.c b/palacios/src/devices/lnx_virtio_blk.c
index 787d965..7bc41a6 100644
--- a/palacios/src/devices/lnx_virtio_blk.c
+++ b/palacios/src/devices/lnx_virtio_blk.c
@@ -20,13 +20,18 @@
 #include <palacios/vmm.h>
 #include <palacios/vmm_dev_mgr.h>
 #include <devices/lnx_virtio_pci.h>
-#include <devices/lnx_virtio_blk.h>
-#include <devices/block_dev.h>
 #include <palacios/vm_guest_mem.h>
 
 #include <devices/pci.h>
 
 
+
+#ifndef CONFIG_DEBUG_VIRTIO_BLK
+#undef PrintDebug
+#define PrintDebug(fmt, args...)
+#endif
+
+
 #define BLK_CAPACITY_PORT     20
 #define BLK_MAX_SIZE_PORT     28
 #define BLK_MAX_SEG_PORT      32
@@ -71,26 +76,30 @@ struct blk_op_hdr {
 #define VIRTIO_LEGACY_GEOM   0x10       /* Indicates support of legacy geometry */
 
 
-
+struct virtio_dev_state {
+    struct vm_device * pci_bus;
+    struct list_head dev_list;
+    struct guest_info * vm;
+};
 
 struct virtio_blk_state {
+
+    struct pci_device * pci_dev;
     struct blk_config block_cfg;
     struct virtio_config virtio_cfg;
 
-    struct vm_device * pci_bus;
-    struct pci_device * pci_dev;
     
     struct virtio_queue queue;
 
-    union {
-	struct v3_cd_ops * cd_ops;
-	struct v3_hd_ops * hd_ops;
-    };
+    struct v3_dev_blk_ops * ops;
 
-    v3_block_type_t block_type;
     void * backend_data;
 
     int io_range_size;
+
+    struct virtio_dev_state * virtio_dev;
+
+    struct list_head dev_link;
 };
 
 
@@ -98,8 +107,7 @@ static int virtio_free(struct vm_device * dev) {
     return -1;
 }
 
-static int virtio_reset(struct vm_device * dev) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data;
+static int blk_reset(struct virtio_blk_state * virtio) {
 
     virtio->queue.ring_desc_addr = 0;
     virtio->queue.ring_avail_addr = 0;
@@ -109,106 +117,76 @@ static int virtio_reset(struct vm_device * dev) {
 
     virtio->virtio_cfg.status = 0;
     virtio->virtio_cfg.pci_isr = 0;
-
     return 0;
 }
 
-static int handle_read_op(struct vm_device * dev, uint8_t * buf, uint64_t sector, uint32_t len) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data; 
-
-    if (virtio->block_type == BLOCK_DISK) {
-	if (len % HD_SECTOR_SIZE) {
-	    PrintError("Write of something that is not a sector len %d, mod=%d\n", len, len % HD_SECTOR_SIZE);
-	    return -1;
-	}
-
 
-	PrintDebug("Reading Disk\n");
-
-	return virtio->hd_ops->read(buf, len / HD_SECTOR_SIZE, sector * HD_SECTOR_SIZE, virtio->backend_data);
-    } else if (virtio->block_type == BLOCK_CDROM) {
-	if (len % ATAPI_BLOCK_SIZE) {
-	    PrintError("Write of something that is not an ATAPI block len %d, mod=%d\n", len, len % ATAPI_BLOCK_SIZE);
-	    return -1;
-	}
-
-	return virtio->cd_ops->read(buf, len / ATAPI_BLOCK_SIZE, sector * ATAPI_BLOCK_SIZE, virtio->backend_data);
+static int virtio_reset(struct vm_device * dev) {
+    struct virtio_dev_state * dev_state = (struct virtio_dev_state *)(dev->private_data);
+    struct virtio_blk_state * blk_state = NULL;
 
+    list_for_each_entry(blk_state, &(dev_state->dev_list), dev_link) {
+	blk_reset(blk_state);
     }
 
-    return -1;
+    return 0;
 }
 
+static int handle_read_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
+    int ret = -1;
 
-static int handle_write_op(struct vm_device * dev, uint8_t * buf, uint64_t sector, uint32_t len) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data; 
+    PrintDebug("Reading Disk\n");
+    ret = blk_state->ops->read(buf, *sector, len, (void *)(blk_state->backend_data));
+    *sector += len;
 
+    return ret;
+}
 
-    if (virtio->block_type == BLOCK_DISK) {
-	if (len % HD_SECTOR_SIZE) {
-	    PrintError("Write of something that is not a sector len %d, mod=%d\n", len, len % HD_SECTOR_SIZE);
-	    return -1;
-	}
 
-	PrintDebug("Writing Disk\n");
+static int handle_write_op(struct virtio_blk_state * blk_state, uint8_t * buf, uint64_t * sector, uint64_t len) {
+    int ret = -1;
 
-	return virtio->hd_ops->write(buf, len / HD_SECTOR_SIZE, sector * HD_SECTOR_SIZE, virtio->backend_data);
-    }
+    PrintDebug("Writing Disk\n");
+    ret = blk_state->ops->write(buf, *sector, len, (void *)(blk_state->backend_data));
+    *sector += len;
 
-    return -1;
+    return ret;
 }
 
 
-static int handle_block_op(struct vm_device * dev, struct vring_desc * hdr_desc, 
-			   struct vring_desc * buf_desc, struct vring_desc * status_desc) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data;    
-    struct blk_op_hdr * hdr = NULL;
-    uint8_t * buf = NULL;
-    uint8_t * status = NULL;
-
 
-    PrintDebug("Handling Block op\n");
+// multiple block operations need to increment the sector 
 
-    if (guest_pa_to_host_va(dev->vm, hdr_desc->addr_gpa, (addr_t *)&(hdr)) == -1) {
-	PrintError("Could not translate block header address\n");
-	return -1;
-    }
+static int handle_block_op(struct virtio_blk_state * blk_state, struct blk_op_hdr * hdr, 
+			   struct vring_desc * buf_desc, uint8_t * status) {
+    uint8_t * buf = NULL;
 
-    if (guest_pa_to_host_va(dev->vm, buf_desc->addr_gpa, (addr_t *)&(buf)) == -1) {
+    PrintDebug("Handling Block op\n");
+    if (guest_pa_to_host_va(blk_state->virtio_dev->vm, buf_desc->addr_gpa, (addr_t *)&(buf)) == -1) {
 	PrintError("Could not translate buffer address\n");
 	return -1;
     }
 
-    if (guest_pa_to_host_va(dev->vm, status_desc->addr_gpa, (addr_t *)&(status)) == -1) {
-	PrintError("Could not translate status address\n");
-	return -1;
-    }
-
     PrintDebug("Sector=%p Length=%d\n", (void *)(addr_t)(hdr->sector), buf_desc->length);
 
     if (hdr->type == BLK_IN_REQ) {
-	if (virtio->block_type != BLOCK_NONE) {
-	    if (handle_read_op(dev, buf, hdr->sector, buf_desc->length) == -1) {
-		*status = BLK_STATUS_ERR;
-	    } else {
-		*status = BLK_STATUS_OK;
-	    }
+	if (handle_read_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
+	    *status = BLK_STATUS_ERR;
+	    return -1;
 	} else {
-	    *status = BLK_STATUS_NOT_SUPPORTED;
-	} 
-
+	    *status = BLK_STATUS_OK;
+	}
     } else if (hdr->type == BLK_OUT_REQ) {
-	if (virtio->block_type == BLOCK_DISK) {
-	    if (handle_write_op(dev, buf, hdr->sector, buf_desc->length) == -1) {
-		*status = BLK_STATUS_ERR;
-	    } else {
-		*status = BLK_STATUS_OK;
-	    }
+	if (handle_write_op(blk_state, buf, &(hdr->sector), buf_desc->length) == -1) {
+	    *status = BLK_STATUS_ERR;
+	    return -1;
 	} else {
-	    *status = BLK_STATUS_NOT_SUPPORTED;
+	    *status = BLK_STATUS_OK;
 	}
     } else if (hdr->type == BLK_SCSI_CMD) {
+	PrintError("VIRTIO: SCSI Command Not supported!!!\n");
 	*status = BLK_STATUS_NOT_SUPPORTED;
+	return -1;
     }
 
     PrintDebug("Returning Status: %d\n", *status);
@@ -216,88 +194,117 @@ static int handle_block_op(struct vm_device * dev, struct vring_desc * hdr_desc,
     return 0;
 }
 
+static int get_desc_count(struct virtio_queue * q, int index) {
+    struct vring_desc * tmp_desc = &(q->desc[index]);
+    int cnt = 1;
+    
+    while (tmp_desc->flags & VIRTIO_NEXT_FLAG) {
+	tmp_desc = &(q->desc[tmp_desc->next]);
+	cnt++;
+    }
+
+    return cnt;
+}
+
 
 
-static int handle_kick(struct vm_device * dev) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data;    
-    struct virtio_queue * q = &(virtio->queue);
+static int handle_kick(struct virtio_blk_state * blk_state) {  
+    struct virtio_queue * q = &(blk_state->queue);
 
-    PrintDebug("VIRTIO KICK: cur_index=%d, avail_index=%d\n", q->cur_avail_idx, q->avail->index);
+    PrintDebug("VIRTIO KICK: cur_index=%d (mod=%d), avail_index=%d\n", 
+	       q->cur_avail_idx, q->cur_avail_idx % QUEUE_SIZE, q->avail->index);
 
     while (q->cur_avail_idx < q->avail->index) {
 	struct vring_desc * hdr_desc = NULL;
 	struct vring_desc * buf_desc = NULL;
 	struct vring_desc * status_desc = NULL;
-	uint16_t chain_idx = q->avail->ring[q->cur_avail_idx];
+	struct blk_op_hdr hdr;
+	addr_t hdr_addr = 0;
+	uint16_t desc_idx = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
+	int desc_cnt = get_desc_count(q, desc_idx);
+	int i = 0;
+	uint8_t * status_ptr = NULL;
+	uint8_t status = BLK_STATUS_OK;
 	uint32_t req_len = 0;
-	int chained = 1;
 
-	PrintDebug("chained=%d, Chain Index=%d\n", chained, chain_idx);
+	PrintDebug("Descriptor Count=%d, index=%d\n", desc_cnt, q->cur_avail_idx % QUEUE_SIZE);
 
-	while (chained) {
-	    hdr_desc = &(q->desc[chain_idx]);
-	    
-	    PrintDebug("Header Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", hdr_desc, 
-		       (void *)(hdr_desc->addr_gpa), hdr_desc->length, hdr_desc->flags, hdr_desc->next);
+	if (desc_cnt < 3) {
+	    PrintError("Block operations must include at least 3 descriptors\n");
+	    return -1;
+	}
+
+	hdr_desc = &(q->desc[desc_idx]);
+
+
+	PrintDebug("Header Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", hdr_desc, 
+		   (void *)(hdr_desc->addr_gpa), hdr_desc->length, hdr_desc->flags, hdr_desc->next);	
+
+	if (guest_pa_to_host_va(blk_state->virtio_dev->vm, hdr_desc->addr_gpa, &(hdr_addr)) == -1) {
+	    PrintError("Could not translate block header address\n");
+	    return -1;
+	}
+
+	// We copy the block op header out because we are going to modify its contents
+	memcpy(&hdr, (void *)hdr_addr, sizeof(struct blk_op_hdr));
 	
-	    if (!(hdr_desc->flags & VIRTIO_NEXT_FLAG)) {
-		PrintError("Block operations must chain a buffer descriptor\n");
-		return -1;
-	    }
+	PrintDebug("Blk Op Hdr (ptr=%p) type=%d, sector=%p\n", (void *)hdr_addr, hdr.type, (void *)hdr.sector);
+
+	desc_idx = hdr_desc->next;
+
+	for (i = 0; i < desc_cnt - 2; i++) {
+	    uint8_t tmp_status = BLK_STATUS_OK;
+
+	    buf_desc = &(q->desc[desc_idx]);
 
-	    buf_desc = &(q->desc[hdr_desc->next]);
-	    
 	    PrintDebug("Buffer Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", buf_desc, 
 		       (void *)(buf_desc->addr_gpa), buf_desc->length, buf_desc->flags, buf_desc->next);
-	    
-	    if (!(buf_desc->flags & VIRTIO_NEXT_FLAG)) {
-		PrintError("Block operatoins must chain a status descriptor\n");
+
+	    if (handle_block_op(blk_state, &hdr, buf_desc, &tmp_status) == -1) {
+		PrintError("Error handling block operation\n");
 		return -1;
 	    }
-	    
-	    status_desc = &(q->desc[buf_desc->next]);
 
-	    // We detect whether we are chained here...
-	    if (status_desc->flags & VIRTIO_NEXT_FLAG) {
-		chained = 1;
-		chain_idx = status_desc->next; 
-	    } else {
-		chained = 0;
+	    if (tmp_status != BLK_STATUS_OK) {
+		status = tmp_status;
 	    }
 
-	    PrintDebug("Status Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", status_desc, 
-		       (void *)(status_desc->addr_gpa), status_desc->length, status_desc->flags, status_desc->next);
-	    
+	    req_len += buf_desc->length;
+	    desc_idx = buf_desc->next;
+	}
 
-	    if (handle_block_op(dev, hdr_desc, buf_desc, status_desc) == -1) {
-		PrintError("Error handling block operation\n");
-		return -1;
-	    }
+	status_desc = &(q->desc[desc_idx]);
 
-	    req_len += (buf_desc->length + status_desc->length);
-	}
+	PrintDebug("Status Descriptor (ptr=%p) gpa=%p, len=%d, flags=%x, next=%d\n", status_desc, 
+		   (void *)(status_desc->addr_gpa), status_desc->length, status_desc->flags, status_desc->next);
 
-	q->used->ring[q->used->index].id = q->avail->ring[q->cur_avail_idx];
-	q->used->ring[q->used->index].length = req_len; // What do we set this to????
+	if (guest_pa_to_host_va(blk_state->virtio_dev->vm, status_desc->addr_gpa, (addr_t *)&(status_ptr)) == -1) {
+	    PrintError("Could not translate status address\n");
+	    return -1;
+	}
 
-	q->used->index = (q->used->index + 1) % (QUEUE_SIZE * sizeof(struct vring_desc));;
+	req_len += status_desc->length;
+	*status_ptr = status;
 
+	q->used->ring[q->used->index % QUEUE_SIZE].id = q->avail->ring[q->cur_avail_idx % QUEUE_SIZE];
+	q->used->ring[q->used->index % QUEUE_SIZE].length = req_len; // What do we set this to????
 
-	q->cur_avail_idx = (q->cur_avail_idx + 1) % (QUEUE_SIZE * sizeof(struct vring_desc));
+	q->used->index++;
+	q->cur_avail_idx++;
     }
 
     if (!(q->avail->flags & VIRTIO_NO_IRQ_FLAG)) {
-	PrintDebug("Raising IRQ %d\n",  virtio->pci_dev->config_header.intr_line);
-	v3_pci_raise_irq(virtio->pci_bus, 0, virtio->pci_dev);
-	virtio->virtio_cfg.pci_isr = 1;
+	PrintDebug("Raising IRQ %d\n",  blk_state->pci_dev->config_header.intr_line);
+	v3_pci_raise_irq(blk_state->virtio_dev->pci_bus, 0, blk_state->pci_dev);
+	blk_state->virtio_cfg.pci_isr = 1;
     }
 
     return 0;
 }
 
-static int virtio_io_write(uint16_t port, void * src, uint_t length, struct vm_device * dev) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data;
-    int port_idx = port % virtio->io_range_size;
+static int virtio_io_write(uint16_t port, void * src, uint_t length, void * private_data) {
+    struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
+    int port_idx = port % blk_state->io_range_size;
 
 
     PrintDebug("VIRTIO BLOCK Write for port %d (index=%d) len=%d, value=%x\n", 
@@ -312,7 +319,8 @@ static int virtio_io_write(uint16_t port, void * src, uint_t length, struct vm_d
 		return -1;
 	    }
 	    
-	    virtio->virtio_cfg.guest_features = *(uint32_t *)src;
+	    blk_state->virtio_cfg.guest_features = *(uint32_t *)src;
+	    PrintDebug("Setting Guest Features to %x\n", blk_state->virtio_cfg.guest_features);
 
 	    break;
 	case VRING_PG_NUM_PORT:
@@ -321,41 +329,41 @@ static int virtio_io_write(uint16_t port, void * src, uint_t length, struct vm_d
 		addr_t page_addr = (pfn << VIRTIO_PAGE_SHIFT);
 
 
-		virtio->queue.pfn = pfn;
+		blk_state->queue.pfn = pfn;
 		
-		virtio->queue.ring_desc_addr = page_addr ;
-		virtio->queue.ring_avail_addr = page_addr + (QUEUE_SIZE * sizeof(struct vring_desc));
-		virtio->queue.ring_used_addr = ( virtio->queue.ring_avail_addr + \
+		blk_state->queue.ring_desc_addr = page_addr ;
+		blk_state->queue.ring_avail_addr = page_addr + (QUEUE_SIZE * sizeof(struct vring_desc));
+		blk_state->queue.ring_used_addr = ( blk_state->queue.ring_avail_addr + \
 						 sizeof(struct vring_avail)    + \
 						 (QUEUE_SIZE * sizeof(uint16_t)));
 		
 		// round up to next page boundary.
-		virtio->queue.ring_used_addr = (virtio->queue.ring_used_addr + 0xfff) & ~0xfff;
+		blk_state->queue.ring_used_addr = (blk_state->queue.ring_used_addr + 0xfff) & ~0xfff;
 
-		if (guest_pa_to_host_va(dev->vm, virtio->queue.ring_desc_addr, (addr_t *)&(virtio->queue.desc)) == -1) {
+		if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_desc_addr, (addr_t *)&(blk_state->queue.desc)) == -1) {
 		    PrintError("Could not translate ring descriptor address\n");
 		    return -1;
 		}
 
 
-		if (guest_pa_to_host_va(dev->vm, virtio->queue.ring_avail_addr, (addr_t *)&(virtio->queue.avail)) == -1) {
+		if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_avail_addr, (addr_t *)&(blk_state->queue.avail)) == -1) {
 		    PrintError("Could not translate ring available address\n");
 		    return -1;
 		}
 
 
-		if (guest_pa_to_host_va(dev->vm, virtio->queue.ring_used_addr, (addr_t *)&(virtio->queue.used)) == -1) {
+		if (guest_pa_to_host_va(blk_state->virtio_dev->vm, blk_state->queue.ring_used_addr, (addr_t *)&(blk_state->queue.used)) == -1) {
 		    PrintError("Could not translate ring used address\n");
 		    return -1;
 		}
 
 		PrintDebug("RingDesc_addr=%p, Avail_addr=%p, Used_addr=%p\n",
-			   (void *)(virtio->queue.ring_desc_addr),
-			   (void *)(virtio->queue.ring_avail_addr),
-			   (void *)(virtio->queue.ring_used_addr));
+			   (void *)(blk_state->queue.ring_desc_addr),
+			   (void *)(blk_state->queue.ring_avail_addr),
+			   (void *)(blk_state->queue.ring_used_addr));
 
 		PrintDebug("RingDesc=%p, Avail=%p, Used=%p\n", 
-			   virtio->queue.desc, virtio->queue.avail, virtio->queue.used);
+			   blk_state->queue.desc, blk_state->queue.avail, blk_state->queue.used);
 
 	    } else {
 		PrintError("Illegal write length for page frame number\n");
@@ -363,34 +371,34 @@ static int virtio_io_write(uint16_t port, void * src, uint_t length, struct vm_d
 	    }
 	    break;
 	case VRING_Q_SEL_PORT:
-	    virtio->virtio_cfg.vring_queue_selector = *(uint16_t *)src;
+	    blk_state->virtio_cfg.vring_queue_selector = *(uint16_t *)src;
 
-	    if (virtio->virtio_cfg.vring_queue_selector != 0) {
+	    if (blk_state->virtio_cfg.vring_queue_selector != 0) {
 		PrintError("Virtio Block device only uses 1 queue, selected %d\n", 
-			   virtio->virtio_cfg.vring_queue_selector);
+			   blk_state->virtio_cfg.vring_queue_selector);
 		return -1;
 	    }
 
 	    break;
 	case VRING_Q_NOTIFY_PORT:
 	    PrintDebug("Handling Kick\n");
-	    if (handle_kick(dev) == -1) {
+	    if (handle_kick(blk_state) == -1) {
 		PrintError("Could not handle Block Notification\n");
 		return -1;
 	    }
 	    break;
 	case VIRTIO_STATUS_PORT:
-	    virtio->virtio_cfg.status = *(uint8_t *)src;
+	    blk_state->virtio_cfg.status = *(uint8_t *)src;
 
-	    if (virtio->virtio_cfg.status == 0) {
+	    if (blk_state->virtio_cfg.status == 0) {
 		PrintDebug("Resetting device\n");
-		virtio_reset(dev);
+		blk_reset(blk_state);
 	    }
 
 	    break;
 
 	case VIRTIO_ISR_PORT:
-	    virtio->virtio_cfg.pci_isr = *(uint8_t *)src;
+	    blk_state->virtio_cfg.pci_isr = *(uint8_t *)src;
 	    break;
 	default:
 	    return -1;
@@ -401,9 +409,9 @@ static int virtio_io_write(uint16_t port, void * src, uint_t length, struct vm_d
 }
 
 
-static int virtio_io_read(uint16_t port, void * dst, uint_t length, struct vm_device * dev) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data;
-    int port_idx = port % virtio->io_range_size;
+static int virtio_io_read(uint16_t port, void * dst, uint_t length, void * private_data) {
+    struct virtio_blk_state * blk_state = (struct virtio_blk_state *)private_data;
+    int port_idx = port % blk_state->io_range_size;
 
 
     PrintDebug("VIRTIO BLOCK Read  for port %d (index =%d), length=%d\n", 
@@ -416,7 +424,7 @@ static int virtio_io_read(uint16_t port, void * dst, uint_t length, struct vm_de
 		return -1;
 	    }
 
-	    *(uint32_t *)dst = virtio->virtio_cfg.host_features;
+	    *(uint32_t *)dst = blk_state->virtio_cfg.host_features;
 	
 	    break;
 	case VRING_PG_NUM_PORT:
@@ -425,7 +433,7 @@ static int virtio_io_read(uint16_t port, void * dst, uint_t length, struct vm_de
 		return -1;
 	    }
 
-	    *(uint32_t *)dst = virtio->queue.pfn;
+	    *(uint32_t *)dst = blk_state->queue.pfn;
 
 	    break;
 	case VRING_SIZE_PORT:
@@ -434,7 +442,7 @@ static int virtio_io_read(uint16_t port, void * dst, uint_t length, struct vm_de
 		return -1;
 	    }
 		
-	    *(uint16_t *)dst = virtio->queue.queue_size;
+	    *(uint16_t *)dst = blk_state->queue.queue_size;
 
 	    break;
 
@@ -444,21 +452,22 @@ static int virtio_io_read(uint16_t port, void * dst, uint_t length, struct vm_de
 		return -1;
 	    }
 
-	    *(uint8_t *)dst = virtio->virtio_cfg.status;
+	    *(uint8_t *)dst = blk_state->virtio_cfg.status;
 	    break;
 
 	case VIRTIO_ISR_PORT:
-	    *(uint8_t *)dst = virtio->virtio_cfg.pci_isr;
-	    virtio->virtio_cfg.pci_isr = 0;
-	    v3_pci_lower_irq(virtio->pci_bus, 0, virtio->pci_dev);
+	    *(uint8_t *)dst = blk_state->virtio_cfg.pci_isr;
+	    blk_state->virtio_cfg.pci_isr = 0;
+	    v3_pci_lower_irq(blk_state->virtio_dev->pci_bus, 0, blk_state->pci_dev);
 	    break;
 
 	default:
 	    if ( (port_idx >= sizeof(struct virtio_config)) && 
 		 (port_idx < (sizeof(struct virtio_config) + sizeof(struct blk_config))) ) {
+		int cfg_offset = port_idx - sizeof(struct virtio_config);
+		uint8_t * cfg_ptr = (uint8_t *)&(blk_state->block_cfg);
 
-		uint8_t * cfg_ptr = (uint8_t *)&(virtio->block_cfg);
-		memcpy(dst, cfg_ptr, length);
+		memcpy(dst, cfg_ptr + cfg_offset, length);
 		
 	    } else {
 		PrintError("Read of Unhandled Virtio Read\n");
@@ -476,7 +485,7 @@ static int virtio_io_read(uint16_t port, void * dst, uint_t length, struct vm_de
 
 static struct v3_device_ops dev_ops = {
     .free = virtio_free,
-    .reset = NULL,
+    .reset = virtio_reset,
     .start = NULL,
     .stop = NULL,
 };
@@ -484,133 +493,145 @@ static struct v3_device_ops dev_ops = {
 
 
 
-int v3_virtio_register_cdrom(struct vm_device * dev, struct v3_cd_ops * ops, void * private_data) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data;
-    
-    virtio->block_type = BLOCK_CDROM;
-    virtio->cd_ops = ops;
-    virtio->backend_data = private_data;
-
-    virtio->block_cfg.capacity = ops->get_capacity(private_data);
-
-    return 0;
-}
-
-
-int v3_virtio_register_harddisk(struct vm_device * dev, struct v3_hd_ops * ops, void * private_data) {
-    struct virtio_blk_state * virtio = (struct virtio_blk_state *)dev->private_data;
-
-    virtio->block_type = BLOCK_DISK;
-    virtio->hd_ops = ops;
-    virtio->backend_data = private_data;
-
-    virtio->block_cfg.capacity = ops->get_capacity(private_data);
-
-    return 0;
-}
-
-
 
-static int virtio_init(struct guest_info * vm, void * cfg_data) {
-    struct vm_device * pci_bus = v3_find_dev(vm, (char *)cfg_data);
-    struct virtio_blk_state * virtio_state = NULL;
+static int register_dev(struct virtio_dev_state * virtio, struct virtio_blk_state * blk_state) {
+    // initialize PCI
     struct pci_device * pci_dev = NULL;
+    struct v3_pci_bar bars[6];
+    int num_ports = sizeof(struct virtio_config) + sizeof(struct blk_config);
+    int tmp_ports = num_ports;
+    int i;
 
-    PrintDebug("Initializing VIRTIO Block device\n");
 
-    if (pci_bus == NULL) {
-	PrintError("VirtIO devices require a PCI Bus");
-	return -1;
-    }
 
+    // This gets the number of ports, rounded up to a power of 2
+    blk_state->io_range_size = 1; // must be a power of 2
     
-    virtio_state  = (struct virtio_blk_state *)V3_Malloc(sizeof(struct virtio_blk_state));
-    memset(virtio_state, 0, sizeof(struct virtio_blk_state));
-
-
-    struct vm_device * dev = v3_allocate_device("LNX_VIRTIO_BLK", &dev_ops, virtio_state);
-    if (v3_attach_device(vm, dev) == -1) {
-	PrintError("Could not attach device %s\n", "LNX_VIRTIO_BLK");
+    while (tmp_ports > 0) {
+	tmp_ports >>= 1;
+	blk_state->io_range_size <<= 1;
+    }
+	
+    // this is to account for any low order bits being set in num_ports
+    // if there are none, then num_ports was already a power of 2 so we shift right to reset it
+    if ((num_ports & ((blk_state->io_range_size >> 1) - 1)) == 0) {
+	blk_state->io_range_size >>= 1;
+    }
+    
+    
+    for (i = 0; i < 6; i++) {
+	bars[i].type = PCI_BAR_NONE;
+    }
+    
+    PrintDebug("Virtio-BLK io_range_size = %d\n", blk_state->io_range_size);
+    
+    bars[0].type = PCI_BAR_IO;
+    bars[0].default_base_port = -1;
+    bars[0].num_ports = blk_state->io_range_size;
+    
+    bars[0].io_read = virtio_io_read;
+    bars[0].io_write = virtio_io_write;
+    bars[0].private_data = blk_state;
+    
+    pci_dev = v3_pci_register_device(virtio->pci_bus, PCI_STD_DEVICE, 
+				     0, PCI_AUTO_DEV_NUM, 0,
+				     "LNX_VIRTIO_BLK", bars,
+				     NULL, NULL, NULL, blk_state);
+    
+    if (!pci_dev) {
+	PrintError("Could not register PCI Device\n");
 	return -1;
     }
+    
+    pci_dev->config_header.vendor_id = VIRTIO_VENDOR_ID;
+    pci_dev->config_header.subsystem_vendor_id = VIRTIO_SUBVENDOR_ID;
+    
+    
+    pci_dev->config_header.device_id = VIRTIO_BLOCK_DEV_ID;
+    pci_dev->config_header.class = PCI_CLASS_STORAGE;
+    pci_dev->config_header.subclass = PCI_STORAGE_SUBCLASS_OTHER;
+    
+    pci_dev->config_header.subsystem_id = VIRTIO_BLOCK_SUBDEVICE_ID;
+    
+    
+    pci_dev->config_header.intr_pin = 1;
+    
+    pci_dev->config_header.max_latency = 1; // ?? (qemu does it...)
+    
+    
+    blk_state->pci_dev = pci_dev;
+    
+    /* Block configuration */
+    blk_state->virtio_cfg.host_features = VIRTIO_SEG_MAX;
+    blk_state->block_cfg.max_seg = QUEUE_SIZE - 2;
 
+    // Virtio Block only uses one queue
+    blk_state->queue.queue_size = QUEUE_SIZE;
 
-    // PCI initialization
-    {
-	struct v3_pci_bar bars[6];
-	int num_ports = sizeof(struct virtio_config) + sizeof(struct blk_config);
-	int tmp_ports = num_ports;
-	int i;
+    blk_state->virtio_dev = virtio;
 
+    blk_reset(blk_state);
 
 
-	// This gets the number of ports, rounded up to a power of 2
-	virtio_state->io_range_size = 1; // must be a power of 2
+    return 0;
+}
 
-	while (tmp_ports > 0) {
-	    tmp_ports >>= 1;
-	    virtio_state->io_range_size <<= 1;
-	}
-	
-	// this is to account for any low order bits being set in num_ports
-	// if there are none, then num_ports was already a power of 2 so we shift right to reset it
-	if ((num_ports & ((virtio_state->io_range_size >> 1) - 1)) == 0) {
-	    virtio_state->io_range_size >>= 1;
-	}
 
+static int connect_fn(struct guest_info * info, 
+		      void * frontend_data, 
+		      struct v3_dev_blk_ops * ops, 
+		      v3_cfg_tree_t * cfg, 
+		      void * private_data) {
 
-	for (i = 0; i < 6; i++) {
-	    bars[i].type = PCI_BAR_NONE;
-	}
+    struct virtio_dev_state * virtio = (struct virtio_dev_state *)frontend_data;
 
-	bars[0].type = PCI_BAR_IO;
-	bars[0].default_base_port = -1;
-	bars[0].num_ports = virtio_state->io_range_size;
+    struct virtio_blk_state * blk_state  = (struct virtio_blk_state *)V3_Malloc(sizeof(struct virtio_blk_state));
+    memset(blk_state, 0, sizeof(struct virtio_blk_state));
 
-	bars[0].io_read = virtio_io_read;
-	bars[0].io_write = virtio_io_write;
+    register_dev(virtio, blk_state);
 
-	pci_dev = v3_pci_register_device(pci_bus, PCI_STD_DEVICE, 
-					 0, PCI_AUTO_DEV_NUM, 0,
-					 "LNX_VIRTIO_BLK", bars,
-					 NULL, NULL, NULL, dev);
+    blk_state->ops = ops;
+    blk_state->backend_data = private_data;
 
-	if (!pci_dev) {
-	    PrintError("Could not register PCI Device\n");
-	    return -1;
-	}
-	
-	pci_dev->config_header.vendor_id = VIRTIO_VENDOR_ID;
-	pci_dev->config_header.subsystem_vendor_id = VIRTIO_SUBVENDOR_ID;
-	
+    blk_state->block_cfg.capacity = ops->get_capacity(private_data);
 
-	pci_dev->config_header.device_id = VIRTIO_BLOCK_DEV_ID;
-	pci_dev->config_header.class = PCI_CLASS_STORAGE;
-	pci_dev->config_header.subclass = PCI_STORAGE_SUBCLASS_OTHER;
-    
-	pci_dev->config_header.subsystem_id = VIRTIO_BLOCK_SUBDEVICE_ID;
+    PrintDebug("Virtio Capacity = %d -- 0x%p\n", (int)(virtio->block_cfg.capacity), 
+	       (void *)(addr_t)(virtio->block_cfg.capacity));
 
+    return 0;
+}
 
-	pci_dev->config_header.intr_pin = 1;
 
-	pci_dev->config_header.max_latency = 1; // ?? (qemu does it...)
+static int virtio_init(struct guest_info * vm, v3_cfg_tree_t * cfg) {
+    struct vm_device * pci_bus = v3_find_dev(vm, v3_cfg_val(cfg, "bus"));
+    struct virtio_dev_state * virtio_state = NULL;
+    char * name = v3_cfg_val(cfg, "name");
 
+    PrintDebug("Initializing VIRTIO Block device\n");
 
-	virtio_state->pci_dev = pci_dev;
-	virtio_state->pci_bus = pci_bus;
+    if (pci_bus == NULL) {
+	PrintError("VirtIO devices require a PCI Bus");
+	return -1;
     }
 
-    /* Block configuration */
-    virtio_state->virtio_cfg.host_features = VIRTIO_SEG_MAX;
 
-    // Virtio Block only uses one queue
-    virtio_state->queue.queue_size = QUEUE_SIZE;
+    virtio_state  = (struct virtio_dev_state *)V3_Malloc(sizeof(struct virtio_dev_state));
+    memset(virtio_state, 0, sizeof(struct virtio_dev_state));
 
-    virtio_reset(dev);
+    INIT_LIST_HEAD(&(virtio_state->dev_list));
+    virtio_state->pci_bus = pci_bus;
+    virtio_state->vm = vm;
 
-    virtio_state->backend_data = NULL;
-    virtio_state->block_type = BLOCK_NONE;
-    virtio_state->hd_ops = NULL;
+    struct vm_device * dev = v3_allocate_device(name, &dev_ops, virtio_state);
+    if (v3_attach_device(vm, dev) == -1) {
+	PrintError("Could not attach device %s\n", name);
+	return -1;
+    }
+
+    if (v3_dev_add_blk_frontend(vm, name, connect_fn, (void *)virtio_state) == -1) {
+	PrintError("Could not register %s as block frontend\n", name);
+	return -1;
+    }
 
     return 0;
 }