| /* |
| * Virtio Support |
| * |
| * Copyright IBM, Corp. 2007 |
| * |
| * Authors: |
| * Anthony Liguori <aliguori@us.ibm.com> |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2. See |
| * the COPYING file in the top-level directory. |
| * |
| */ |
| |
| #include <inttypes.h> |
| |
| #include "trace.h" |
| #include "qemu/error-report.h" |
| #include "hw/virtio/virtio.h" |
| #include "qemu/atomic.h" |
| #include "hw/virtio/virtio-bus.h" |
| |
| /* The alignment to use between consumer and producer parts of vring. |
| * x86 pagesize again. */ |
| #define VIRTIO_PCI_VRING_ALIGN 4096 |
| |
| typedef struct VRingDesc |
| { |
| uint64_t addr; |
| uint32_t len; |
| uint16_t flags; |
| uint16_t next; |
| } VRingDesc; |
| |
| typedef struct VRingAvail |
| { |
| uint16_t flags; |
| uint16_t idx; |
| uint16_t ring[0]; |
| } VRingAvail; |
| |
| typedef struct VRingUsedElem |
| { |
| uint32_t id; |
| uint32_t len; |
| } VRingUsedElem; |
| |
| typedef struct VRingUsed |
| { |
| uint16_t flags; |
| uint16_t idx; |
| VRingUsedElem ring[0]; |
| } VRingUsed; |
| |
| typedef struct VRing |
| { |
| unsigned int num; |
| hwaddr desc; |
| hwaddr avail; |
| hwaddr used; |
| } VRing; |
| |
| struct VirtQueue |
| { |
| VRing vring; |
| hwaddr pa; |
| uint16_t last_avail_idx; |
| /* Last used index value we have signalled on */ |
| uint16_t signalled_used; |
| |
| /* Last used index value we have signalled on */ |
| bool signalled_used_valid; |
| |
| /* Notification enabled? */ |
| bool notification; |
| |
| uint16_t queue_index; |
| |
| int inuse; |
| |
| uint16_t vector; |
| void (*handle_output)(VirtIODevice *vdev, VirtQueue *vq); |
| VirtIODevice *vdev; |
| EventNotifier guest_notifier; |
| EventNotifier host_notifier; |
| }; |
| |
| /* virt queue functions */ |
| static void virtqueue_init(VirtQueue *vq) |
| { |
| hwaddr pa = vq->pa; |
| |
| vq->vring.desc = pa; |
| vq->vring.avail = pa + vq->vring.num * sizeof(VRingDesc); |
| vq->vring.used = vring_align(vq->vring.avail + |
| offsetof(VRingAvail, ring[vq->vring.num]), |
| VIRTIO_PCI_VRING_ALIGN); |
| } |
| |
| static inline uint64_t vring_desc_addr(hwaddr desc_pa, int i) |
| { |
| hwaddr pa; |
| pa = desc_pa + sizeof(VRingDesc) * i + offsetof(VRingDesc, addr); |
| return ldq_phys(pa); |
| } |
| |
| static inline uint32_t vring_desc_len(hwaddr desc_pa, int i) |
| { |
| hwaddr pa; |
| pa = desc_pa + sizeof(VRingDesc) * i + offsetof(VRingDesc, len); |
| return ldl_phys(pa); |
| } |
| |
| static inline uint16_t vring_desc_flags(hwaddr desc_pa, int i) |
| { |
| hwaddr pa; |
| pa = desc_pa + sizeof(VRingDesc) * i + offsetof(VRingDesc, flags); |
| return lduw_phys(pa); |
| } |
| |
| static inline uint16_t vring_desc_next(hwaddr desc_pa, int i) |
| { |
| hwaddr pa; |
| pa = desc_pa + sizeof(VRingDesc) * i + offsetof(VRingDesc, next); |
| return lduw_phys(pa); |
| } |
| |
| static inline uint16_t vring_avail_flags(VirtQueue *vq) |
| { |
| hwaddr pa; |
| pa = vq->vring.avail + offsetof(VRingAvail, flags); |
| return lduw_phys(pa); |
| } |
| |
| static inline uint16_t vring_avail_idx(VirtQueue *vq) |
| { |
| hwaddr pa; |
| pa = vq->vring.avail + offsetof(VRingAvail, idx); |
| return lduw_phys(pa); |
| } |
| |
| static inline uint16_t vring_avail_ring(VirtQueue *vq, int i) |
| { |
| hwaddr pa; |
| pa = vq->vring.avail + offsetof(VRingAvail, ring[i]); |
| return lduw_phys(pa); |
| } |
| |
| static inline uint16_t vring_used_event(VirtQueue *vq) |
| { |
| return vring_avail_ring(vq, vq->vring.num); |
| } |
| |
| static inline void vring_used_ring_id(VirtQueue *vq, int i, uint32_t val) |
| { |
| hwaddr pa; |
| pa = vq->vring.used + offsetof(VRingUsed, ring[i].id); |
| stl_phys(pa, val); |
| } |
| |
| static inline void vring_used_ring_len(VirtQueue *vq, int i, uint32_t val) |
| { |
| hwaddr pa; |
| pa = vq->vring.used + offsetof(VRingUsed, ring[i].len); |
| stl_phys(pa, val); |
| } |
| |
| static uint16_t vring_used_idx(VirtQueue *vq) |
| { |
| hwaddr pa; |
| pa = vq->vring.used + offsetof(VRingUsed, idx); |
| return lduw_phys(pa); |
| } |
| |
| static inline void vring_used_idx_set(VirtQueue *vq, uint16_t val) |
| { |
| hwaddr pa; |
| pa = vq->vring.used + offsetof(VRingUsed, idx); |
| stw_phys(pa, val); |
| } |
| |
| static inline void vring_used_flags_set_bit(VirtQueue *vq, int mask) |
| { |
| hwaddr pa; |
| pa = vq->vring.used + offsetof(VRingUsed, flags); |
| stw_phys(pa, lduw_phys(pa) | mask); |
| } |
| |
| static inline void vring_used_flags_unset_bit(VirtQueue *vq, int mask) |
| { |
| hwaddr pa; |
| pa = vq->vring.used + offsetof(VRingUsed, flags); |
| stw_phys(pa, lduw_phys(pa) & ~mask); |
| } |
| |
| static inline void vring_avail_event(VirtQueue *vq, uint16_t val) |
| { |
| hwaddr pa; |
| if (!vq->notification) { |
| return; |
| } |
| pa = vq->vring.used + offsetof(VRingUsed, ring[vq->vring.num]); |
| stw_phys(pa, val); |
| } |
| |
| void virtio_queue_set_notification(VirtQueue *vq, int enable) |
| { |
| vq->notification = enable; |
| if (vq->vdev->guest_features & (1 << VIRTIO_RING_F_EVENT_IDX)) { |
| vring_avail_event(vq, vring_avail_idx(vq)); |
| } else if (enable) { |
| vring_used_flags_unset_bit(vq, VRING_USED_F_NO_NOTIFY); |
| } else { |
| vring_used_flags_set_bit(vq, VRING_USED_F_NO_NOTIFY); |
| } |
| if (enable) { |
| /* Expose avail event/used flags before caller checks the avail idx. */ |
| smp_mb(); |
| } |
| } |
| |
| int virtio_queue_ready(VirtQueue *vq) |
| { |
| return vq->vring.avail != 0; |
| } |
| |
| int virtio_queue_empty(VirtQueue *vq) |
| { |
| return vring_avail_idx(vq) == vq->last_avail_idx; |
| } |
| |
| void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, |
| unsigned int len, unsigned int idx) |
| { |
| unsigned int offset; |
| int i; |
| |
| trace_virtqueue_fill(vq, elem, len, idx); |
| |
| offset = 0; |
| for (i = 0; i < elem->in_num; i++) { |
| size_t size = MIN(len - offset, elem->in_sg[i].iov_len); |
| |
| cpu_physical_memory_unmap(elem->in_sg[i].iov_base, |
| elem->in_sg[i].iov_len, |
| 1, size); |
| |
| offset += size; |
| } |
| |
| for (i = 0; i < elem->out_num; i++) |
| cpu_physical_memory_unmap(elem->out_sg[i].iov_base, |
| elem->out_sg[i].iov_len, |
| 0, elem->out_sg[i].iov_len); |
| |
| idx = (idx + vring_used_idx(vq)) % vq->vring.num; |
| |
| /* Get a pointer to the next entry in the used ring. */ |
| vring_used_ring_id(vq, idx, elem->index); |
| vring_used_ring_len(vq, idx, len); |
| } |
| |
| void virtqueue_flush(VirtQueue *vq, unsigned int count) |
| { |
| uint16_t old, new; |
| /* Make sure buffer is written before we update index. */ |
| smp_wmb(); |
| trace_virtqueue_flush(vq, count); |
| old = vring_used_idx(vq); |
| new = old + count; |
| vring_used_idx_set(vq, new); |
| vq->inuse -= count; |
| if (unlikely((int16_t)(new - vq->signalled_used) < (uint16_t)(new - old))) |
| vq->signalled_used_valid = false; |
| } |
| |
| void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, |
| unsigned int len) |
| { |
| virtqueue_fill(vq, elem, len, 0); |
| virtqueue_flush(vq, 1); |
| } |
| |
| static int virtqueue_num_heads(VirtQueue *vq, unsigned int idx) |
| { |
| uint16_t num_heads = vring_avail_idx(vq) - idx; |
| |
| /* Check it isn't doing very strange things with descriptor numbers. */ |
| if (num_heads > vq->vring.num) { |
| error_report("Guest moved used index from %u to %u", |
| idx, vring_avail_idx(vq)); |
| exit(1); |
| } |
| /* On success, callers read a descriptor at vq->last_avail_idx. |
| * Make sure descriptor read does not bypass avail index read. */ |
| if (num_heads) { |
| smp_rmb(); |
| } |
| |
| return num_heads; |
| } |
| |
| static unsigned int virtqueue_get_head(VirtQueue *vq, unsigned int idx) |
| { |
| unsigned int head; |
| |
| /* Grab the next descriptor number they're advertising, and increment |
| * the index we've seen. */ |
| head = vring_avail_ring(vq, idx % vq->vring.num); |
| |
| /* If their number is silly, that's a fatal mistake. */ |
| if (head >= vq->vring.num) { |
| error_report("Guest says index %u is available", head); |
| exit(1); |
| } |
| |
| return head; |
| } |
| |
| static unsigned virtqueue_next_desc(hwaddr desc_pa, |
| unsigned int i, unsigned int max) |
| { |
| unsigned int next; |
| |
| /* If this descriptor says it doesn't chain, we're done. */ |
| if (!(vring_desc_flags(desc_pa, i) & VRING_DESC_F_NEXT)) |
| return max; |
| |
| /* Check they're not leading us off end of descriptors. */ |
| next = vring_desc_next(desc_pa, i); |
| /* Make sure compiler knows to grab that: we don't want it changing! */ |
| smp_wmb(); |
| |
| if (next >= max) { |
| error_report("Desc next is %u", next); |
| exit(1); |
| } |
| |
| return next; |
| } |
| |
| void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, |
| unsigned int *out_bytes, |
| unsigned max_in_bytes, unsigned max_out_bytes) |
| { |
| unsigned int idx; |
| unsigned int total_bufs, in_total, out_total; |
| |
| idx = vq->last_avail_idx; |
| |
| total_bufs = in_total = out_total = 0; |
| while (virtqueue_num_heads(vq, idx)) { |
| unsigned int max, num_bufs, indirect = 0; |
| hwaddr desc_pa; |
| int i; |
| |
| max = vq->vring.num; |
| num_bufs = total_bufs; |
| i = virtqueue_get_head(vq, idx++); |
| desc_pa = vq->vring.desc; |
| |
| if (vring_desc_flags(desc_pa, i) & VRING_DESC_F_INDIRECT) { |
| if (vring_desc_len(desc_pa, i) % sizeof(VRingDesc)) { |
| error_report("Invalid size for indirect buffer table"); |
| exit(1); |
| } |
| |
| /* If we've got too many, that implies a descriptor loop. */ |
| if (num_bufs >= max) { |
| error_report("Looped descriptor"); |
| exit(1); |
| } |
| |
| /* loop over the indirect descriptor table */ |
| indirect = 1; |
| max = vring_desc_len(desc_pa, i) / sizeof(VRingDesc); |
| num_bufs = i = 0; |
| desc_pa = vring_desc_addr(desc_pa, i); |
| } |
| |
| do { |
| /* If we've got too many, that implies a descriptor loop. */ |
| if (++num_bufs > max) { |
| error_report("Looped descriptor"); |
| exit(1); |
| } |
| |
| if (vring_desc_flags(desc_pa, i) & VRING_DESC_F_WRITE) { |
| in_total += vring_desc_len(desc_pa, i); |
| } else { |
| out_total += vring_desc_len(desc_pa, i); |
| } |
| if (in_total >= max_in_bytes && out_total >= max_out_bytes) { |
| goto done; |
| } |
| } while ((i = virtqueue_next_desc(desc_pa, i, max)) != max); |
| |
| if (!indirect) |
| total_bufs = num_bufs; |
| else |
| total_bufs++; |
| } |
| done: |
| if (in_bytes) { |
| *in_bytes = in_total; |
| } |
| if (out_bytes) { |
| *out_bytes = out_total; |
| } |
| } |
| |
| int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes, |
| unsigned int out_bytes) |
| { |
| unsigned int in_total, out_total; |
| |
| virtqueue_get_avail_bytes(vq, &in_total, &out_total, in_bytes, out_bytes); |
| return in_bytes <= in_total && out_bytes <= out_total; |
| } |
| |
| void virtqueue_map_sg(struct iovec *sg, hwaddr *addr, |
| size_t num_sg, int is_write) |
| { |
| unsigned int i; |
| hwaddr len; |
| |
| for (i = 0; i < num_sg; i++) { |
| len = sg[i].iov_len; |
| sg[i].iov_base = cpu_physical_memory_map(addr[i], &len, is_write); |
| if (sg[i].iov_base == NULL || len != sg[i].iov_len) { |
| error_report("virtio: trying to map MMIO memory"); |
| exit(1); |
| } |
| } |
| } |
| |
| int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem) |
| { |
| unsigned int i, head, max; |
| hwaddr desc_pa = vq->vring.desc; |
| |
| if (!virtqueue_num_heads(vq, vq->last_avail_idx)) |
| return 0; |
| |
| /* When we start there are none of either input nor output. */ |
| elem->out_num = elem->in_num = 0; |
| |
| max = vq->vring.num; |
| |
| i = head = virtqueue_get_head(vq, vq->last_avail_idx++); |
| if (vq->vdev->guest_features & (1 << VIRTIO_RING_F_EVENT_IDX)) { |
| vring_avail_event(vq, vring_avail_idx(vq)); |
| } |
| |
| if (vring_desc_flags(desc_pa, i) & VRING_DESC_F_INDIRECT) { |
| if (vring_desc_len(desc_pa, i) % sizeof(VRingDesc)) { |
| error_report("Invalid size for indirect buffer table"); |
| exit(1); |
| } |
| |
| /* loop over the indirect descriptor table */ |
| max = vring_desc_len(desc_pa, i) / sizeof(VRingDesc); |
| desc_pa = vring_desc_addr(desc_pa, i); |
| i = 0; |
| } |
| |
| /* Collect all the descriptors */ |
| do { |
| struct iovec *sg; |
| |
| if (vring_desc_flags(desc_pa, i) & VRING_DESC_F_WRITE) { |
| if (elem->in_num >= ARRAY_SIZE(elem->in_sg)) { |
| error_report("Too many write descriptors in indirect table"); |
| exit(1); |
| } |
| elem->in_addr[elem->in_num] = vring_desc_addr(desc_pa, i); |
| sg = &elem->in_sg[elem->in_num++]; |
| } else { |
| if (elem->out_num >= ARRAY_SIZE(elem->out_sg)) { |
| error_report("Too many read descriptors in indirect table"); |
| exit(1); |
| } |
| elem->out_addr[elem->out_num] = vring_desc_addr(desc_pa, i); |
| sg = &elem->out_sg[elem->out_num++]; |
| } |
| |
| sg->iov_len = vring_desc_len(desc_pa, i); |
| |
| /* If we've got too many, that implies a descriptor loop. */ |
| if ((elem->in_num + elem->out_num) > max) { |
| error_report("Looped descriptor"); |
| exit(1); |
| } |
| } while ((i = virtqueue_next_desc(desc_pa, i, max)) != max); |
| |
| /* Now map what we have collected */ |
| virtqueue_map_sg(elem->in_sg, elem->in_addr, elem->in_num, 1); |
| virtqueue_map_sg(elem->out_sg, elem->out_addr, elem->out_num, 0); |
| |
| elem->index = head; |
| |
| vq->inuse++; |
| |
| trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num); |
| return elem->in_num + elem->out_num; |
| } |
| |
| /* virtio device */ |
| static void virtio_notify_vector(VirtIODevice *vdev, uint16_t vector) |
| { |
| if (vdev->binding->notify) { |
| vdev->binding->notify(vdev->binding_opaque, vector); |
| } |
| } |
| |
| void virtio_update_irq(VirtIODevice *vdev) |
| { |
| virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); |
| } |
| |
| void virtio_set_status(VirtIODevice *vdev, uint8_t val) |
| { |
| trace_virtio_set_status(vdev, val); |
| |
| if (vdev->set_status) { |
| vdev->set_status(vdev, val); |
| } |
| vdev->status = val; |
| } |
| |
| void virtio_reset(void *opaque) |
| { |
| VirtIODevice *vdev = opaque; |
| int i; |
| |
| virtio_set_status(vdev, 0); |
| |
| if (vdev->reset) |
| vdev->reset(vdev); |
| |
| vdev->guest_features = 0; |
| vdev->queue_sel = 0; |
| vdev->status = 0; |
| vdev->isr = 0; |
| vdev->config_vector = VIRTIO_NO_VECTOR; |
| virtio_notify_vector(vdev, vdev->config_vector); |
| |
| for(i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { |
| vdev->vq[i].vring.desc = 0; |
| vdev->vq[i].vring.avail = 0; |
| vdev->vq[i].vring.used = 0; |
| vdev->vq[i].last_avail_idx = 0; |
| vdev->vq[i].pa = 0; |
| vdev->vq[i].vector = VIRTIO_NO_VECTOR; |
| vdev->vq[i].signalled_used = 0; |
| vdev->vq[i].signalled_used_valid = false; |
| vdev->vq[i].notification = true; |
| } |
| } |
| |
| uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr) |
| { |
| uint8_t val; |
| |
| vdev->get_config(vdev, vdev->config); |
| |
| if (addr > (vdev->config_len - sizeof(val))) |
| return (uint32_t)-1; |
| |
| val = ldub_p(vdev->config + addr); |
| return val; |
| } |
| |
| uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr) |
| { |
| uint16_t val; |
| |
| vdev->get_config(vdev, vdev->config); |
| |
| if (addr > (vdev->config_len - sizeof(val))) |
| return (uint32_t)-1; |
| |
| val = lduw_p(vdev->config + addr); |
| return val; |
| } |
| |
| uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr) |
| { |
| uint32_t val; |
| |
| vdev->get_config(vdev, vdev->config); |
| |
| if (addr > (vdev->config_len - sizeof(val))) |
| return (uint32_t)-1; |
| |
| val = ldl_p(vdev->config + addr); |
| return val; |
| } |
| |
| void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data) |
| { |
| uint8_t val = data; |
| |
| if (addr > (vdev->config_len - sizeof(val))) |
| return; |
| |
| stb_p(vdev->config + addr, val); |
| |
| if (vdev->set_config) |
| vdev->set_config(vdev, vdev->config); |
| } |
| |
| void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data) |
| { |
| uint16_t val = data; |
| |
| if (addr > (vdev->config_len - sizeof(val))) |
| return; |
| |
| stw_p(vdev->config + addr, val); |
| |
| if (vdev->set_config) |
| vdev->set_config(vdev, vdev->config); |
| } |
| |
| void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data) |
| { |
| uint32_t val = data; |
| |
| if (addr > (vdev->config_len - sizeof(val))) |
| return; |
| |
| stl_p(vdev->config + addr, val); |
| |
| if (vdev->set_config) |
| vdev->set_config(vdev, vdev->config); |
| } |
| |
| void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr) |
| { |
| vdev->vq[n].pa = addr; |
| virtqueue_init(&vdev->vq[n]); |
| } |
| |
| hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].pa; |
| } |
| |
| int virtio_queue_get_num(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].vring.num; |
| } |
| |
| int virtio_queue_get_id(VirtQueue *vq) |
| { |
| VirtIODevice *vdev = vq->vdev; |
| assert(vq >= &vdev->vq[0] && vq < &vdev->vq[VIRTIO_PCI_QUEUE_MAX]); |
| return vq - &vdev->vq[0]; |
| } |
| |
| void virtio_queue_notify_vq(VirtQueue *vq) |
| { |
| if (vq->vring.desc) { |
| VirtIODevice *vdev = vq->vdev; |
| trace_virtio_queue_notify(vdev, vq - vdev->vq, vq); |
| vq->handle_output(vdev, vq); |
| } |
| } |
| |
| void virtio_queue_notify(VirtIODevice *vdev, int n) |
| { |
| virtio_queue_notify_vq(&vdev->vq[n]); |
| } |
| |
| uint16_t virtio_queue_vector(VirtIODevice *vdev, int n) |
| { |
| return n < VIRTIO_PCI_QUEUE_MAX ? vdev->vq[n].vector : |
| VIRTIO_NO_VECTOR; |
| } |
| |
| void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector) |
| { |
| if (n < VIRTIO_PCI_QUEUE_MAX) |
| vdev->vq[n].vector = vector; |
| } |
| |
| VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, |
| void (*handle_output)(VirtIODevice *, VirtQueue *)) |
| { |
| int i; |
| |
| for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { |
| if (vdev->vq[i].vring.num == 0) |
| break; |
| } |
| |
| if (i == VIRTIO_PCI_QUEUE_MAX || queue_size > VIRTQUEUE_MAX_SIZE) |
| abort(); |
| |
| vdev->vq[i].vring.num = queue_size; |
| vdev->vq[i].handle_output = handle_output; |
| |
| return &vdev->vq[i]; |
| } |
| |
| void virtio_del_queue(VirtIODevice *vdev, int n) |
| { |
| if (n < 0 || n >= VIRTIO_PCI_QUEUE_MAX) { |
| abort(); |
| } |
| |
| vdev->vq[n].vring.num = 0; |
| } |
| |
| void virtio_irq(VirtQueue *vq) |
| { |
| trace_virtio_irq(vq); |
| vq->vdev->isr |= 0x01; |
| virtio_notify_vector(vq->vdev, vq->vector); |
| } |
| |
| /* Assuming a given event_idx value from the other size, if |
| * we have just incremented index from old to new_idx, |
| * should we trigger an event? */ |
| static inline int vring_need_event(uint16_t event, uint16_t new, uint16_t old) |
| { |
| /* Note: Xen has similar logic for notification hold-off |
| * in include/xen/interface/io/ring.h with req_event and req_prod |
| * corresponding to event_idx + 1 and new respectively. |
| * Note also that req_event and req_prod in Xen start at 1, |
| * event indexes in virtio start at 0. */ |
| return (uint16_t)(new - event - 1) < (uint16_t)(new - old); |
| } |
| |
| static bool vring_notify(VirtIODevice *vdev, VirtQueue *vq) |
| { |
| uint16_t old, new; |
| bool v; |
| /* We need to expose used array entries before checking used event. */ |
| smp_mb(); |
| /* Always notify when queue is empty (when feature acknowledge) */ |
| if (((vdev->guest_features & (1 << VIRTIO_F_NOTIFY_ON_EMPTY)) && |
| !vq->inuse && vring_avail_idx(vq) == vq->last_avail_idx)) { |
| return true; |
| } |
| |
| if (!(vdev->guest_features & (1 << VIRTIO_RING_F_EVENT_IDX))) { |
| return !(vring_avail_flags(vq) & VRING_AVAIL_F_NO_INTERRUPT); |
| } |
| |
| v = vq->signalled_used_valid; |
| vq->signalled_used_valid = true; |
| old = vq->signalled_used; |
| new = vq->signalled_used = vring_used_idx(vq); |
| return !v || vring_need_event(vring_used_event(vq), new, old); |
| } |
| |
| void virtio_notify(VirtIODevice *vdev, VirtQueue *vq) |
| { |
| if (!vring_notify(vdev, vq)) { |
| return; |
| } |
| |
| trace_virtio_notify(vdev, vq); |
| vdev->isr |= 0x01; |
| virtio_notify_vector(vdev, vq->vector); |
| } |
| |
| void virtio_notify_config(VirtIODevice *vdev) |
| { |
| if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) |
| return; |
| |
| vdev->isr |= 0x03; |
| virtio_notify_vector(vdev, vdev->config_vector); |
| } |
| |
| void virtio_save(VirtIODevice *vdev, QEMUFile *f) |
| { |
| int i; |
| |
| if (vdev->binding->save_config) |
| vdev->binding->save_config(vdev->binding_opaque, f); |
| |
| qemu_put_8s(f, &vdev->status); |
| qemu_put_8s(f, &vdev->isr); |
| qemu_put_be16s(f, &vdev->queue_sel); |
| qemu_put_be32s(f, &vdev->guest_features); |
| qemu_put_be32(f, vdev->config_len); |
| qemu_put_buffer(f, vdev->config, vdev->config_len); |
| |
| for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { |
| if (vdev->vq[i].vring.num == 0) |
| break; |
| } |
| |
| qemu_put_be32(f, i); |
| |
| for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { |
| if (vdev->vq[i].vring.num == 0) |
| break; |
| |
| qemu_put_be32(f, vdev->vq[i].vring.num); |
| qemu_put_be64(f, vdev->vq[i].pa); |
| qemu_put_be16s(f, &vdev->vq[i].last_avail_idx); |
| if (vdev->binding->save_queue) |
| vdev->binding->save_queue(vdev->binding_opaque, i, f); |
| } |
| } |
| |
| int virtio_set_features(VirtIODevice *vdev, uint32_t val) |
| { |
| uint32_t supported_features = |
| vdev->binding->get_features(vdev->binding_opaque); |
| bool bad = (val & ~supported_features) != 0; |
| |
| val &= supported_features; |
| if (vdev->set_features) { |
| vdev->set_features(vdev, val); |
| } |
| vdev->guest_features = val; |
| return bad ? -1 : 0; |
| } |
| |
| int virtio_load(VirtIODevice *vdev, QEMUFile *f) |
| { |
| int num, i, ret; |
| uint32_t features; |
| uint32_t supported_features; |
| |
| if (vdev->binding->load_config) { |
| ret = vdev->binding->load_config(vdev->binding_opaque, f); |
| if (ret) |
| return ret; |
| } |
| |
| qemu_get_8s(f, &vdev->status); |
| qemu_get_8s(f, &vdev->isr); |
| qemu_get_be16s(f, &vdev->queue_sel); |
| qemu_get_be32s(f, &features); |
| |
| if (virtio_set_features(vdev, features) < 0) { |
| supported_features = vdev->binding->get_features(vdev->binding_opaque); |
| error_report("Features 0x%x unsupported. Allowed features: 0x%x", |
| features, supported_features); |
| return -1; |
| } |
| vdev->config_len = qemu_get_be32(f); |
| qemu_get_buffer(f, vdev->config, vdev->config_len); |
| |
| num = qemu_get_be32(f); |
| |
| for (i = 0; i < num; i++) { |
| vdev->vq[i].vring.num = qemu_get_be32(f); |
| vdev->vq[i].pa = qemu_get_be64(f); |
| qemu_get_be16s(f, &vdev->vq[i].last_avail_idx); |
| vdev->vq[i].signalled_used_valid = false; |
| vdev->vq[i].notification = true; |
| |
| if (vdev->vq[i].pa) { |
| uint16_t nheads; |
| virtqueue_init(&vdev->vq[i]); |
| nheads = vring_avail_idx(&vdev->vq[i]) - vdev->vq[i].last_avail_idx; |
| /* Check it isn't doing very strange things with descriptor numbers. */ |
| if (nheads > vdev->vq[i].vring.num) { |
| error_report("VQ %d size 0x%x Guest index 0x%x " |
| "inconsistent with Host index 0x%x: delta 0x%x", |
| i, vdev->vq[i].vring.num, |
| vring_avail_idx(&vdev->vq[i]), |
| vdev->vq[i].last_avail_idx, nheads); |
| return -1; |
| } |
| } else if (vdev->vq[i].last_avail_idx) { |
| error_report("VQ %d address 0x0 " |
| "inconsistent with Host index 0x%x", |
| i, vdev->vq[i].last_avail_idx); |
| return -1; |
| } |
| if (vdev->binding->load_queue) { |
| ret = vdev->binding->load_queue(vdev->binding_opaque, i, f); |
| if (ret) |
| return ret; |
| } |
| } |
| |
| virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); |
| return 0; |
| } |
| |
| void virtio_common_cleanup(VirtIODevice *vdev) |
| { |
| qemu_del_vm_change_state_handler(vdev->vmstate); |
| g_free(vdev->config); |
| g_free(vdev->vq); |
| } |
| |
| void virtio_cleanup(VirtIODevice *vdev) |
| { |
| virtio_common_cleanup(vdev); |
| g_free(vdev); |
| } |
| |
| static void virtio_vmstate_change(void *opaque, int running, RunState state) |
| { |
| VirtIODevice *vdev = opaque; |
| bool backend_run = running && (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK); |
| vdev->vm_running = running; |
| |
| if (backend_run) { |
| virtio_set_status(vdev, vdev->status); |
| } |
| |
| if (vdev->binding->vmstate_change) { |
| vdev->binding->vmstate_change(vdev->binding_opaque, backend_run); |
| } |
| |
| if (!backend_run) { |
| virtio_set_status(vdev, vdev->status); |
| } |
| } |
| |
| void virtio_init(VirtIODevice *vdev, const char *name, |
| uint16_t device_id, size_t config_size) |
| { |
| int i; |
| vdev->device_id = device_id; |
| vdev->status = 0; |
| vdev->isr = 0; |
| vdev->queue_sel = 0; |
| vdev->config_vector = VIRTIO_NO_VECTOR; |
| vdev->vq = g_malloc0(sizeof(VirtQueue) * VIRTIO_PCI_QUEUE_MAX); |
| vdev->vm_running = runstate_is_running(); |
| for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { |
| vdev->vq[i].vector = VIRTIO_NO_VECTOR; |
| vdev->vq[i].vdev = vdev; |
| vdev->vq[i].queue_index = i; |
| } |
| |
| vdev->name = name; |
| vdev->config_len = config_size; |
| if (vdev->config_len) { |
| vdev->config = g_malloc0(config_size); |
| } else { |
| vdev->config = NULL; |
| } |
| vdev->vmstate = qemu_add_vm_change_state_handler(virtio_vmstate_change, |
| vdev); |
| } |
| |
| VirtIODevice *virtio_common_init(const char *name, uint16_t device_id, |
| size_t config_size, size_t struct_size) |
| { |
| VirtIODevice *vdev; |
| vdev = g_malloc0(struct_size); |
| virtio_init(vdev, name, device_id, config_size); |
| return vdev; |
| } |
| |
| void virtio_bind_device(VirtIODevice *vdev, const VirtIOBindings *binding, |
| DeviceState *opaque) |
| { |
| vdev->binding = binding; |
| vdev->binding_opaque = opaque; |
| } |
| |
| hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].vring.desc; |
| } |
| |
| hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].vring.avail; |
| } |
| |
| hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].vring.used; |
| } |
| |
| hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].vring.desc; |
| } |
| |
| hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n) |
| { |
| return sizeof(VRingDesc) * vdev->vq[n].vring.num; |
| } |
| |
| hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n) |
| { |
| return offsetof(VRingAvail, ring) + |
| sizeof(uint64_t) * vdev->vq[n].vring.num; |
| } |
| |
| hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n) |
| { |
| return offsetof(VRingUsed, ring) + |
| sizeof(VRingUsedElem) * vdev->vq[n].vring.num; |
| } |
| |
| hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].vring.used - vdev->vq[n].vring.desc + |
| virtio_queue_get_used_size(vdev, n); |
| } |
| |
| uint16_t virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq[n].last_avail_idx; |
| } |
| |
| void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx) |
| { |
| vdev->vq[n].last_avail_idx = idx; |
| } |
| |
| VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n) |
| { |
| return vdev->vq + n; |
| } |
| |
| uint16_t virtio_get_queue_index(VirtQueue *vq) |
| { |
| return vq->queue_index; |
| } |
| |
| static void virtio_queue_guest_notifier_read(EventNotifier *n) |
| { |
| VirtQueue *vq = container_of(n, VirtQueue, guest_notifier); |
| if (event_notifier_test_and_clear(n)) { |
| virtio_irq(vq); |
| } |
| } |
| |
| void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign, |
| bool with_irqfd) |
| { |
| if (assign && !with_irqfd) { |
| event_notifier_set_handler(&vq->guest_notifier, |
| virtio_queue_guest_notifier_read); |
| } else { |
| event_notifier_set_handler(&vq->guest_notifier, NULL); |
| } |
| if (!assign) { |
| /* Test and clear notifier before closing it, |
| * in case poll callback didn't have time to run. */ |
| virtio_queue_guest_notifier_read(&vq->guest_notifier); |
| } |
| } |
| |
| EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq) |
| { |
| return &vq->guest_notifier; |
| } |
| |
| static void virtio_queue_host_notifier_read(EventNotifier *n) |
| { |
| VirtQueue *vq = container_of(n, VirtQueue, host_notifier); |
| if (event_notifier_test_and_clear(n)) { |
| virtio_queue_notify_vq(vq); |
| } |
| } |
| |
| void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign, |
| bool set_handler) |
| { |
| if (assign && set_handler) { |
| event_notifier_set_handler(&vq->host_notifier, |
| virtio_queue_host_notifier_read); |
| } else { |
| event_notifier_set_handler(&vq->host_notifier, NULL); |
| } |
| if (!assign) { |
| /* Test and clear notifier before after disabling event, |
| * in case poll callback didn't have time to run. */ |
| virtio_queue_host_notifier_read(&vq->host_notifier); |
| } |
| } |
| |
| EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq) |
| { |
| return &vq->host_notifier; |
| } |
| |
| static int virtio_device_init(DeviceState *qdev) |
| { |
| VirtIODevice *vdev = VIRTIO_DEVICE(qdev); |
| VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(qdev); |
| assert(k->init != NULL); |
| if (k->init(vdev) < 0) { |
| return -1; |
| } |
| virtio_bus_plug_device(vdev); |
| return 0; |
| } |
| |
| static void virtio_device_class_init(ObjectClass *klass, void *data) |
| { |
| /* Set the default value here. */ |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| dc->init = virtio_device_init; |
| dc->bus_type = TYPE_VIRTIO_BUS; |
| } |
| |
| static const TypeInfo virtio_device_info = { |
| .name = TYPE_VIRTIO_DEVICE, |
| .parent = TYPE_DEVICE, |
| .instance_size = sizeof(VirtIODevice), |
| .class_init = virtio_device_class_init, |
| .abstract = true, |
| .class_size = sizeof(VirtioDeviceClass), |
| }; |
| |
| static void virtio_register_types(void) |
| { |
| type_register_static(&virtio_device_info); |
| } |
| |
| type_init(virtio_register_types) |