diff -r ffa851df0825 -r 2fb8b9db1c86 symbian-qemu-0.9.1-12/qemu-symbian-svp/hw/virtio.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/symbian-qemu-0.9.1-12/qemu-symbian-svp/hw/virtio.c Fri Jul 31 15:01:17 2009 +0100 @@ -0,0 +1,699 @@ +/* + * Virtio Support + * + * Copyright IBM, Corp. 2007 + * + * Authors: + * Anthony Liguori + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + +#include + +#include "virtio.h" +#include "sysemu.h" + +//#define VIRTIO_ZERO_COPY + +/* The alignment to use between consumer and producer parts of vring. + * x86 pagesize for historical reasons. */ +#define VIRTIO_VRING_ALIGN 4096 + +/* QEMU doesn't strictly need write barriers since everything runs in + * lock-step. We'll leave the calls to wmb() in though to make it obvious for + * KVM or if kqemu gets SMP support. + */ +#define wmb() do { } while (0) + +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; + target_phys_addr_t desc; + target_phys_addr_t avail; + target_phys_addr_t used; +} VRing; + +struct VirtQueue +{ + VRing vring; + target_phys_addr_t pa; + uint16_t last_avail_idx; + int inuse; + void (*handle_output)(VirtIODevice *vdev, VirtQueue *vq); +}; + +#define VIRTIO_PCI_QUEUE_MAX 16 + +/* virt queue functions */ +#ifdef VIRTIO_ZERO_COPY +static void *virtio_map_gpa(target_phys_addr_t addr, size_t size) +{ + ram_addr_t off; + target_phys_addr_t addr1; + + off = cpu_get_physical_page_desc(addr); + if ((off & ~TARGET_PAGE_MASK) != IO_MEM_RAM) { + fprintf(stderr, "virtio DMA to IO ram\n"); + exit(1); + } + + off = (off & TARGET_PAGE_MASK) | (addr & ~TARGET_PAGE_MASK); + + for (addr1 = addr + TARGET_PAGE_SIZE; + addr1 < TARGET_PAGE_ALIGN(addr + size); + addr1 += TARGET_PAGE_SIZE) { + ram_addr_t off1; + + off1 = cpu_get_physical_page_desc(addr1); + if ((off1 & ~TARGET_PAGE_MASK) != IO_MEM_RAM) { + fprintf(stderr, "virtio DMA to IO ram\n"); + exit(1); + } + + off1 = (off1 & TARGET_PAGE_MASK) | (addr1 & ~TARGET_PAGE_MASK); + + if (off1 != (off + (addr1 - addr))) { + fprintf(stderr, "discontigous virtio memory\n"); + exit(1); + } + } + + return phys_ram_base + off; +} +#endif + +static void virtqueue_init(VirtQueue *vq, target_phys_addr_t 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_VRING_ALIGN); +} + +static inline uint64_t vring_desc_addr(VirtQueue *vq, int i) +{ + target_phys_addr_t pa; + pa = vq->vring.desc + sizeof(VRingDesc) * i + offsetof(VRingDesc, addr); + return ldq_phys(pa); +} + +static inline uint32_t vring_desc_len(VirtQueue *vq, int i) +{ + target_phys_addr_t pa; + pa = vq->vring.desc + sizeof(VRingDesc) * i + offsetof(VRingDesc, len); + return ldl_phys(pa); +} + +static inline uint16_t vring_desc_flags(VirtQueue *vq, int i) +{ + target_phys_addr_t pa; + pa = vq->vring.desc + sizeof(VRingDesc) * i + offsetof(VRingDesc, flags); + return lduw_phys(pa); +} + +static inline uint16_t vring_desc_next(VirtQueue *vq, int i) +{ + target_phys_addr_t pa; + pa = vq->vring.desc + sizeof(VRingDesc) * i + offsetof(VRingDesc, next); + return lduw_phys(pa); +} + +static inline uint16_t vring_avail_flags(VirtQueue *vq) +{ + target_phys_addr_t pa; + pa = vq->vring.avail + offsetof(VRingAvail, flags); + return lduw_phys(pa); +} + +static inline uint16_t vring_avail_idx(VirtQueue *vq) +{ + target_phys_addr_t pa; + pa = vq->vring.avail + offsetof(VRingAvail, idx); + return lduw_phys(pa); +} + +static inline uint16_t vring_avail_ring(VirtQueue *vq, int i) +{ + target_phys_addr_t pa; + pa = vq->vring.avail + offsetof(VRingAvail, ring[i]); + return lduw_phys(pa); +} + +static inline void vring_used_ring_id(VirtQueue *vq, int i, uint32_t val) +{ + target_phys_addr_t 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) +{ + target_phys_addr_t pa; + pa = vq->vring.used + offsetof(VRingUsed, ring[i].len); + stl_phys(pa, val); +} + +static uint16_t vring_used_idx(VirtQueue *vq) +{ + target_phys_addr_t pa; + pa = vq->vring.used + offsetof(VRingUsed, idx); + return lduw_phys(pa); +} + +static inline void vring_used_idx_increment(VirtQueue *vq, uint16_t val) +{ + target_phys_addr_t pa; + pa = vq->vring.used + offsetof(VRingUsed, idx); + stw_phys(pa, vring_used_idx(vq) + val); +} + +static inline void vring_used_flags_set_bit(VirtQueue *vq, int mask) +{ + target_phys_addr_t 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) +{ + target_phys_addr_t pa; + pa = vq->vring.used + offsetof(VRingUsed, flags); + stw_phys(pa, lduw_phys(pa) & ~mask); +} + +void virtio_queue_set_notification(VirtQueue *vq, int enable) +{ + 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); +} + +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; + +#ifndef VIRTIO_ZERO_COPY + for (i = 0; i < elem->out_num; i++) + qemu_free(elem->out_sg[i].iov_base); +#endif + + offset = 0; + for (i = 0; i < elem->in_num; i++) { + size_t size = MIN(len - offset, elem->in_sg[i].iov_len); + +#ifdef VIRTIO_ZERO_COPY + if (size) { + ram_addr_t addr = (uint8_t *)elem->in_sg[i].iov_base - phys_ram_base; + ram_addr_t off; + + for (off = 0; off < size; off += TARGET_PAGE_SIZE) + cpu_physical_memory_set_dirty(addr + off); + } +#else + if (size) + cpu_physical_memory_write(elem->in_addr[i], + elem->in_sg[i].iov_base, + size); + + qemu_free(elem->in_sg[i].iov_base); +#endif + + offset += size; + } + + 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) +{ + /* Make sure buffer is written before we update index. */ + wmb(); + vring_used_idx_increment(vq, count); + vq->inuse -= count; +} + +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) { + fprintf(stderr, "Guest moved used index from %u to %u", + idx, vring_avail_idx(vq)); + exit(1); + } + + 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) { + fprintf(stderr, "Guest says index %u is available", head); + exit(1); + } + + return head; +} + +static unsigned virtqueue_next_desc(VirtQueue *vq, unsigned int i) +{ + unsigned int next; + + /* If this descriptor says it doesn't chain, we're done. */ + if (!(vring_desc_flags(vq, i) & VRING_DESC_F_NEXT)) + return vq->vring.num; + + /* Check they're not leading us off end of descriptors. */ + next = vring_desc_next(vq, i); + /* Make sure compiler knows to grab that: we don't want it changing! */ + wmb(); + + if (next >= vq->vring.num) { + fprintf(stderr, "Desc next is %u", next); + exit(1); + } + + return next; +} + +int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes) +{ + unsigned int idx; + int num_bufs, in_total, out_total; + + idx = vq->last_avail_idx; + + num_bufs = in_total = out_total = 0; + while (virtqueue_num_heads(vq, idx)) { + int i; + + i = virtqueue_get_head(vq, idx++); + do { + /* If we've got too many, that implies a descriptor loop. */ + if (++num_bufs > vq->vring.num) { + fprintf(stderr, "Looped descriptor"); + exit(1); + } + + if (vring_desc_flags(vq, i) & VRING_DESC_F_WRITE) { + if (in_bytes > 0 && + (in_total += vring_desc_len(vq, i)) >= in_bytes) + return 1; + } else { + if (out_bytes > 0 && + (out_total += vring_desc_len(vq, i)) >= out_bytes) + return 1; + } + } while ((i = virtqueue_next_desc(vq, i)) != vq->vring.num); + } + + return 0; +} + +int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem) +{ + unsigned int i, head; + + 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; + + i = head = virtqueue_get_head(vq, vq->last_avail_idx++); + do { + struct iovec *sg; + + if (vring_desc_flags(vq, i) & VRING_DESC_F_WRITE) { + elem->in_addr[elem->in_num] = vring_desc_addr(vq, i); + sg = &elem->in_sg[elem->in_num++]; + } else + sg = &elem->out_sg[elem->out_num++]; + + /* Grab the first descriptor, and check it's OK. */ + sg->iov_len = vring_desc_len(vq, i); + +#ifdef VIRTIO_ZERO_COPY + sg->iov_base = virtio_map_gpa(vring_desc_addr(vq, i), sg->iov_len); +#else + /* cap individual scatter element size to prevent unbounded allocations + of memory from the guest. Practically speaking, no virtio driver + will ever pass more than a page in each element. We set the cap to + be 2MB in case for some reason a large page makes it way into the + sg list. When we implement a zero copy API, this limitation will + disappear */ + if (sg->iov_len > (2 << 20)) + sg->iov_len = 2 << 20; + + sg->iov_base = qemu_malloc(sg->iov_len); + if (sg->iov_base && + !(vring_desc_flags(vq, i) & VRING_DESC_F_WRITE)) { + cpu_physical_memory_read(vring_desc_addr(vq, i), + sg->iov_base, + sg->iov_len); + } +#endif + if (sg->iov_base == NULL) { + fprintf(stderr, "Invalid mapping\n"); + exit(1); + } + + /* If we've got too many, that implies a descriptor loop. */ + if ((elem->in_num + elem->out_num) > vq->vring.num) { + fprintf(stderr, "Looped descriptor"); + exit(1); + } + } while ((i = virtqueue_next_desc(vq, i)) != vq->vring.num); + + elem->index = head; + + vq->inuse++; + + return elem->in_num + elem->out_num; +} + +/* virtio device. */ + +uint32_t virtio_config_readb(void *opaque, uint32_t addr) +{ + VirtIODevice *vdev = opaque; + uint8_t val; + + vdev->get_config(vdev, vdev->config); + + if (addr > (vdev->config_len - sizeof(val))) + return (uint32_t)-1; + + memcpy(&val, vdev->config + addr, sizeof(val)); + return val; +} + +uint32_t virtio_config_readw(void *opaque, uint32_t addr) +{ + VirtIODevice *vdev = opaque; + uint16_t val; + + vdev->get_config(vdev, vdev->config); + + if (addr > (vdev->config_len - sizeof(val))) + return (uint32_t)-1; + + memcpy(&val, vdev->config + addr, sizeof(val)); + return val; +} + +uint32_t virtio_config_readl(void *opaque, uint32_t addr) +{ + VirtIODevice *vdev = opaque; + uint32_t val; + + vdev->get_config(vdev, vdev->config); + + if (addr > (vdev->config_len - sizeof(val))) + return (uint32_t)-1; + + memcpy(&val, vdev->config + addr, sizeof(val)); + return val; +} + +void virtio_config_writeb(void *opaque, uint32_t addr, uint32_t data) +{ + VirtIODevice *vdev = opaque; + uint8_t val = data; + + if (addr > (vdev->config_len - sizeof(val))) + return; + + memcpy(vdev->config + addr, &val, sizeof(val)); + + if (vdev->set_config) + vdev->set_config(vdev, vdev->config); +} + +void virtio_config_writew(void *opaque, uint32_t addr, uint32_t data) +{ + VirtIODevice *vdev = opaque; + uint16_t val = data; + + if (addr > (vdev->config_len - sizeof(val))) + return; + + memcpy(vdev->config + addr, &val, sizeof(val)); + + if (vdev->set_config) + vdev->set_config(vdev, vdev->config); +} + +void virtio_config_writel(void *opaque, uint32_t addr, uint32_t data) +{ + VirtIODevice *vdev = opaque; + uint32_t val = data; + + if (addr > (vdev->config_len - sizeof(val))) + return; + + memcpy(vdev->config + addr, &val, sizeof(val)); + + if (vdev->set_config) + vdev->set_config(vdev, vdev->config); +} + +void virtio_reset(void *opaque) +{ + VirtIODevice *vdev = opaque; + int i; + + if (vdev->reset) + vdev->reset(vdev); + + vdev->features = 0; + vdev->queue_sel = 0; + vdev->status = 0; + vdev->isr = 0; + virtio_update_irq(vdev); + + 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; + } +} + +void virtio_set_vring_addr(VirtIODevice *vdev, int n, target_phys_addr_t pa) +{ + VirtQueue *vq = &vdev->vq[n]; + + vq->pa = pa; + if (pa == 0) { + virtio_reset(vdev); + } else { + virtqueue_init(vq, pa); + } +} + +target_phys_addr_t virtio_get_vring_pa(VirtIODevice *vdev, int n) +{ + VirtQueue *vq = &vdev->vq[n]; + + return vq->pa; +} + +target_phys_addr_t virtio_get_vring_num(VirtIODevice *vdev, int n) +{ + VirtQueue *vq = &vdev->vq[n]; + + return vq->vring.num; +} + +void virtio_kick(VirtIODevice *vdev, int n) +{ + VirtQueue *vq = &vdev->vq[n]; + if (n < VIRTIO_PCI_QUEUE_MAX && vq->vring.desc) + vq->handle_output(vdev, vq); +} + +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_notify(VirtIODevice *vdev, VirtQueue *vq) +{ + /* Always notify when queue is empty */ + if ((vq->inuse || vring_avail_idx(vq) != vq->last_avail_idx) && + (vring_avail_flags(vq) & VRING_AVAIL_F_NO_INTERRUPT)) + return; + + vdev->isr |= 0x01; + virtio_update_irq(vdev); +} + +void virtio_notify_config(VirtIODevice *vdev) +{ + vdev->isr |= 0x03; + virtio_update_irq(vdev); +} + +void virtio_save(VirtIODevice *vdev, QEMUFile *f) +{ + int i; + + vdev->save_binding(vdev, f); + + qemu_put_be32s(f, &vdev->addr); + qemu_put_8s(f, &vdev->status); + qemu_put_8s(f, &vdev->isr); + qemu_put_be16s(f, &vdev->queue_sel); + qemu_put_be32s(f, &vdev->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); + } +} + +void virtio_load(VirtIODevice *vdev, QEMUFile *f) +{ + int num, i; + + vdev->load_binding(vdev, f); + + qemu_get_be32s(f, &vdev->addr); + qemu_get_8s(f, &vdev->status); + qemu_get_8s(f, &vdev->isr); + qemu_get_be16s(f, &vdev->queue_sel); + qemu_get_be32s(f, &vdev->features); + 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); + + if (vdev->vq[i].pa) { + virtqueue_init(&vdev->vq[i], vdev->vq[i].pa); + } + } + + virtio_update_irq(vdev); +} + +VirtIODevice *virtio_init_common(const char *name, size_t config_size, + size_t struct_size) +{ + VirtIODevice *vdev; + + vdev = (VirtIODevice *)qemu_mallocz(struct_size); + vdev->vq = qemu_mallocz(sizeof(VirtQueue) * VIRTIO_PCI_QUEUE_MAX); + + vdev->status = 0; + vdev->isr = 0; + vdev->queue_sel = 0; + vdev->name = name; + vdev->config_len = config_size; + if (vdev->config_len) + vdev->config = qemu_mallocz(config_size); + else + vdev->config = NULL; + + qemu_register_reset(virtio_reset, vdev); + + return vdev; +} +