Michael S. Tsirkin
2013-May-28 16:03 UTC
[PATCH RFC] virtio-pci: new config layout: using memory BAR
This adds support for new config, and is designed to work with the new layout code in Rusty's new layout branch. At the moment all fields are in the same memory BAR (bar 2). This will be used to test performance and compare memory, io and hypercall latency. Compiles but does not work yet. Migration isn't handled yet. It's not clear what do queue_enable/queue_disable fields do, not yet implemented. Gateway for config access with config cycles not yet implemented. Sending out for early review/flames. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- hw/virtio/virtio-pci.c | 393 +++++++++++++++++++++++++++++++++++++++++++-- hw/virtio/virtio-pci.h | 55 +++++++ hw/virtio/virtio.c | 20 +++ include/hw/virtio/virtio.h | 4 + 4 files changed, 458 insertions(+), 14 deletions(-) diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index 752991a..f4db224 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -259,6 +259,26 @@ static void virtio_pci_stop_ioeventfd(VirtIOPCIProxy *proxy) proxy->ioeventfd_started = false; } +static void virtio_pci_set_status(VirtIOPCIProxy *proxy, uint8_t val) +{ + VirtIODevice *vdev = proxy->vdev; + + if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { + virtio_pci_stop_ioeventfd(proxy); + } + + virtio_set_status(vdev, val & 0xFF); + + if (val & VIRTIO_CONFIG_S_DRIVER_OK) { + virtio_pci_start_ioeventfd(proxy); + } + + if (vdev->status == 0) { + virtio_reset(proxy->vdev); + msix_unuse_all_vectors(&proxy->pci_dev); + } +} + static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) { VirtIOPCIProxy *proxy = opaque; @@ -293,20 +313,7 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) } break; case VIRTIO_PCI_STATUS: - if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { - virtio_pci_stop_ioeventfd(proxy); - } - - virtio_set_status(vdev, val & 0xFF); - - if (val & VIRTIO_CONFIG_S_DRIVER_OK) { - virtio_pci_start_ioeventfd(proxy); - } - - if (vdev->status == 0) { - virtio_reset(proxy->vdev); - msix_unuse_all_vectors(&proxy->pci_dev); - } + virtio_pci_set_status(proxy, val); /* Linux before 2.6.34 sets the device as OK without enabling the PCI device bus master bit. In this case we need to disable @@ -455,6 +462,226 @@ static void virtio_pci_config_write(void *opaque, hwaddr addr, } } +static uint64_t virtio_pci_config_common_read(void *opaque, hwaddr addr, + unsigned size) +{ + VirtIOPCIProxy *proxy = opaque; + VirtIODevice *vdev = proxy->vdev; + + uint64_t low = 0xffffffffull; + + switch (addr) { + case offsetof(struct virtio_pci_common_cfg, device_feature_select): + return proxy->device_feature_select; + case offsetof(struct virtio_pci_common_cfg, device_feature): + /* TODO: 64-bit features */ + return proxy->device_feature_select ? 0 : proxy->host_features; + case offsetof(struct virtio_pci_common_cfg, guest_feature_select): + return proxy->guest_feature_select; + case offsetof(struct virtio_pci_common_cfg, guest_feature): + /* TODO: 64-bit features */ + return proxy->guest_feature_select ? 0 : vdev->guest_features; + case offsetof(struct virtio_pci_common_cfg, msix_config): + return vdev->config_vector; + case offsetof(struct virtio_pci_common_cfg, num_queues): + /* TODO: more exact limit? */ + return VIRTIO_PCI_QUEUE_MAX; + case offsetof(struct virtio_pci_common_cfg, device_status): + return vdev->status; + + /* About a specific virtqueue. */ + case offsetof(struct virtio_pci_common_cfg, queue_select): + return vdev->queue_sel; + case offsetof(struct virtio_pci_common_cfg, queue_size): + return virtio_queue_get_num(vdev, vdev->queue_sel); + case offsetof(struct virtio_pci_common_cfg, queue_msix_vector): + return virtio_queue_vector(vdev, vdev->queue_sel); + case offsetof(struct virtio_pci_common_cfg, queue_enable): + /* TODO */ + return 0; + case offsetof(struct virtio_pci_common_cfg, queue_notify_off): + return vdev->queue_sel; + case offsetof(struct virtio_pci_common_cfg, queue_desc): + return virtio_queue_get_desc_addr(vdev, vdev->queue_sel) & low; + case offsetof(struct virtio_pci_common_cfg, queue_desc) + 4: + return virtio_queue_get_desc_addr(vdev, vdev->queue_sel) >> 32; + case offsetof(struct virtio_pci_common_cfg, queue_avail): + return virtio_queue_get_avail_addr(vdev, vdev->queue_sel) & low; + case offsetof(struct virtio_pci_common_cfg, queue_avail) + 4: + return virtio_queue_get_avail_addr(vdev, vdev->queue_sel) >> 32; + case offsetof(struct virtio_pci_common_cfg, queue_used): + return virtio_queue_get_used_addr(vdev, vdev->queue_sel) & low; + case offsetof(struct virtio_pci_common_cfg, queue_used) + 4: + return virtio_queue_get_used_addr(vdev, vdev->queue_sel) >> 32; + default: + return 0; + } +} + +static void virtio_pci_config_common_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size) +{ + VirtIOPCIProxy *proxy = opaque; + VirtIODevice *vdev = proxy->vdev; + + uint64_t low = 0xffffffffull; + uint64_t high = ~low; + + switch (addr) { + case offsetof(struct virtio_pci_common_cfg, device_feature_select): + proxy->device_feature_select = val; + break; + case offsetof(struct virtio_pci_common_cfg, device_feature): + break; + case offsetof(struct virtio_pci_common_cfg, guest_feature_select): + proxy->guest_feature_select = val; + break; + case offsetof(struct virtio_pci_common_cfg, guest_feature): + /* TODO: 64-bit features */ + if (!proxy->guest_feature_select) { + virtio_set_features(vdev, val); + } + break; + case offsetof(struct virtio_pci_common_cfg, msix_config): + vdev->config_vector = val; + break; + case offsetof(struct virtio_pci_common_cfg, num_queues): + break; + case offsetof(struct virtio_pci_common_cfg, device_status): + virtio_pci_set_status(proxy, val); + break; + /* About a specific virtqueue. */ + case offsetof(struct virtio_pci_common_cfg, queue_select): + assert(val < VIRTIO_PCI_QUEUE_MAX); + vdev->queue_sel = val; + break; + case offsetof(struct virtio_pci_common_cfg, queue_size): + assert(val && val < 0x8ffff && !(val & (val - 1))); + virtio_queue_set_num(vdev, vdev->queue_sel, val); + break; + case offsetof(struct virtio_pci_common_cfg, queue_msix_vector): + virtio_queue_set_vector(vdev, vdev->queue_sel, val); + break; + case offsetof(struct virtio_pci_common_cfg, queue_enable): + /* TODO */ + break; + case offsetof(struct virtio_pci_common_cfg, queue_notify_off): + break; + case offsetof(struct virtio_pci_common_cfg, queue_desc): + val &= low; + val |= virtio_queue_get_desc_addr(vdev, vdev->queue_sel) & high; + virtio_queue_set_desc_addr(vdev, vdev->queue_sel, val); + break; + case offsetof(struct virtio_pci_common_cfg, queue_desc) + 4: + val = val << 32; + val |= virtio_queue_get_desc_addr(vdev, vdev->queue_sel) & low; + virtio_queue_set_desc_addr(vdev, vdev->queue_sel, val); + break; + case offsetof(struct virtio_pci_common_cfg, queue_avail): + val &= low; + val |= virtio_queue_get_avail_addr(vdev, vdev->queue_sel) & high; + virtio_queue_set_avail_addr(vdev, vdev->queue_sel, val); + break; + case offsetof(struct virtio_pci_common_cfg, queue_avail) + 4: + val = val << 32; + val |= virtio_queue_get_avail_addr(vdev, vdev->queue_sel) & low; + virtio_queue_set_avail_addr(vdev, vdev->queue_sel, val); + break; + case offsetof(struct virtio_pci_common_cfg, queue_used): + val &= low; + val |= virtio_queue_get_used_addr(vdev, vdev->queue_sel) & high; + virtio_queue_set_used_addr(vdev, vdev->queue_sel, val); + break; + case offsetof(struct virtio_pci_common_cfg, queue_used) + 4: + val = val << 32; + val |= virtio_queue_get_used_addr(vdev, vdev->queue_sel) & low; + virtio_queue_set_used_addr(vdev, vdev->queue_sel, val); + break; + default: + break; + } +} + +static uint64_t virtio_pci_config_isr_read(void *opaque, hwaddr addr, + unsigned size) +{ + VirtIOPCIProxy *proxy = opaque; + VirtIODevice *vdev = proxy->vdev; + uint8_t ret; + + /* reading from the ISR also clears it. */ + ret = vdev->isr; + vdev->isr = 0; + qemu_set_irq(proxy->pci_dev.irq[0], 0); + return ret; +} + +static void virtio_pci_config_isr_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size) +{ +} + +static uint64_t virtio_pci_config_notify_read(void *opaque, hwaddr addr, + unsigned size) +{ + return 0; +} + +static void virtio_pci_config_notify_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size) +{ + VirtIOPCIProxy *proxy = opaque; + VirtIODevice *vdev = proxy->vdev; + if (val < VIRTIO_PCI_QUEUE_MAX) { + virtio_queue_notify(vdev, val); + } +} + +static uint64_t virtio_pci_config_device_read(void *opaque, hwaddr addr, + unsigned size) +{ + VirtIOPCIProxy *proxy = opaque; + uint64_t val = 0; + switch (size) { + case 1: + val = virtio_config_readb(proxy->vdev, addr); + break; + case 2: + val = virtio_config_readw(proxy->vdev, addr); + break; + case 4: + /* Most devices don't have 64 bit config fields. + * Block is an exception: first 8 bytes include + * a 64 bit capacity field. + */ + if (VIRTIO_HOST_IS_BIG_ENDIAN && + proxy->vdev->device_id == VIRTIO_ID_BLOCK && addr < 8) { + /* Swap first two words */ + addr ^= 0x4; + } + val = virtio_config_readl(proxy->vdev, addr); + break; + } + return val; +} + +static void virtio_pci_config_device_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size) +{ + VirtIOPCIProxy *proxy = opaque; + switch (size) { + case 1: + virtio_config_writeb(proxy->vdev, addr, val); + break; + case 2: + virtio_config_writew(proxy->vdev, addr, val); + break; + case 4: + virtio_config_writel(proxy->vdev, addr, val); + break; + } +} + static const MemoryRegionOps virtio_pci_config_ops = { .read = virtio_pci_config_read, .write = virtio_pci_config_write, @@ -465,6 +692,46 @@ static const MemoryRegionOps virtio_pci_config_ops = { .endianness = DEVICE_LITTLE_ENDIAN, }; +static const MemoryRegionOps virtio_pci_config_common_ops = { + .read = virtio_pci_config_common_read, + .write = virtio_pci_config_common_write, + .impl = { + .min_access_size = 1, + .max_access_size = 4, + }, + .endianness = DEVICE_LITTLE_ENDIAN, +}; + +static const MemoryRegionOps virtio_pci_config_isr_ops = { + .read = virtio_pci_config_isr_read, + .write = virtio_pci_config_isr_write, + .impl = { + .min_access_size = 1, + .max_access_size = 1, + }, + .endianness = DEVICE_LITTLE_ENDIAN, +}; + +static const MemoryRegionOps virtio_pci_config_notify_ops = { + .read = virtio_pci_config_notify_read, + .write = virtio_pci_config_notify_write, + .impl = { + .min_access_size = 2, + .max_access_size = 2, + }, + .endianness = DEVICE_LITTLE_ENDIAN, +}; + +static const MemoryRegionOps virtio_pci_config_device_ops = { + .read = virtio_pci_config_device_read, + .write = virtio_pci_config_device_write, + .impl = { + .min_access_size = 1, + .max_access_size = 4, + }, + .endianness = DEVICE_LITTLE_ENDIAN, +}; + static void virtio_write_config(PCIDevice *pci_dev, uint32_t address, uint32_t val, int len) { @@ -949,11 +1216,49 @@ static const TypeInfo virtio_9p_pci_info = { * virtio-pci: This is the PCIDevice which has a virtio-pci-bus. */ +#define VIRTIO_PCI_CONFIG_BAR_NUM 2 + +static void *virtio_pci_cap_add(VirtIOPCIProxy *proxy, + const char *name, + MemoryRegion *reg, + const MemoryRegionOps *ops, + unsigned offset, + unsigned size, + unsigned cap_type, + unsigned cap_length) +{ + struct virtio_pci_cap *cap; + int c; + memory_region_init_io(reg, ops, proxy, name, size); + memory_region_add_subregion(&proxy->config_bar, offset, reg); + + if (!cap_length) { + cap_length = sizeof *cap; + } + c = pci_add_capability(&proxy->pci_dev, PCI_CAP_ID_VNDR, 0, cap_length); + assert(c > 0); + cap = (void *)proxy->pci_dev.config + c; + cap->cap_length = cap_length; + cap->cfg_type = cap_type; + cap->bar = VIRTIO_PCI_CONFIG_BAR_NUM; + cap->offset = offset; + cap->length = size; + + return cap; +} + +static void virtio_pci_cap_del(VirtIOPCIProxy *proxy, MemoryRegion *reg) +{ + memory_region_del_subregion(&proxy->config_bar, reg); + memory_region_destroy(reg); +} + /* This is called by virtio-bus just after the device is plugged. */ static void virtio_pci_device_plugged(DeviceState *d) { VirtIOPCIProxy *proxy = VIRTIO_PCI(d); VirtioBusState *bus = &proxy->bus; + struct virtio_pci_notify_cap *notify_cap; uint8_t *config; uint32_t size; @@ -986,6 +1291,59 @@ static void virtio_pci_device_plugged(DeviceState *d) pci_register_bar(&proxy->pci_dev, 0, PCI_BASE_ADDRESS_SPACE_IO, &proxy->bar); + /* New config layout */ + /* Four capabilities: common, notify, isr, device cfg */ +#define VIRTIO_PCI_CONFIG_BAR_SIZE 0x1000 +#define VIRTIO_PCI_CONFIG_COMMON 0x0 +#define VIRTIO_PCI_CONFIG_NOTIFY 0x100 +#define VIRTIO_PCI_CONFIG_ISR 0x200 +#define VIRTIO_PCI_CONFIG_DEVICE 0x300 + + /* Make sure we left enough space for all vqs */ + assert(VIRTIO_PCI_CONFIG_ISR - VIRTIO_PCI_CONFIG_NOTIFY >+ VIRTIO_PCI_QUEUE_MAX * 2); + assert(VIRTIO_PCI_CONFIG_BAR_SIZE - VIRTIO_PCI_CONFIG_DEVICE >+ proxy->vdev->config_len); + + memory_region_init(&proxy->config_bar, "virtio-pci-config", + VIRTIO_PCI_CONFIG_BAR_SIZE); + + virtio_pci_cap_add(proxy, "virtio-pci-common", + &proxy->config_common, + &virtio_pci_config_common_ops, + VIRTIO_PCI_CONFIG_COMMON, + sizeof(struct virtio_pci_common_cfg), + VIRTIO_PCI_CAP_COMMON_CFG, + 0); + notify_cap = virtio_pci_cap_add(proxy, "virtio-pci-notify", + &proxy->config_notify, + &virtio_pci_config_notify_ops, + VIRTIO_PCI_CONFIG_NOTIFY, + VIRTIO_PCI_QUEUE_MAX * 2, + VIRTIO_PCI_CAP_NOTIFY_CFG, + sizeof *notify_cap); + notify_cap->notify_off_multiplier = 0x2; + virtio_pci_cap_add(proxy, "virtio-pci-isr", + &proxy->config_isr, + &virtio_pci_config_isr_ops, + VIRTIO_PCI_CONFIG_ISR, + 0x1, + VIRTIO_PCI_CAP_ISR_CFG, + 0); + if (proxy->vdev->config_len) { + virtio_pci_cap_add(proxy, "virtio-pci-device", + &proxy->config_device, + &virtio_pci_config_device_ops, + VIRTIO_PCI_CONFIG_DEVICE, + proxy->vdev->config_len, + VIRTIO_PCI_CAP_DEVICE_CFG, + 0); + } + + pci_register_bar(&proxy->pci_dev, VIRTIO_PCI_CONFIG_BAR_NUM, + PCI_BASE_ADDRESS_SPACE_MEMORY, + &proxy->config_bar); + if (!kvm_has_many_ioeventfds()) { proxy->flags &= ~VIRTIO_PCI_FLAG_USE_IOEVENTFD; } @@ -1012,6 +1370,13 @@ static void virtio_pci_exit(PCIDevice *pci_dev) VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev); virtio_pci_stop_ioeventfd(proxy); memory_region_destroy(&proxy->bar); + virtio_pci_cap_del(proxy, &proxy->config_common); + virtio_pci_cap_del(proxy, &proxy->config_notify); + virtio_pci_cap_del(proxy, &proxy->config_isr); + if (&proxy->vdev->config_len) { + virtio_pci_cap_del(proxy, &proxy->config_device); + } + memory_region_destroy(&proxy->config_bar); msix_uninit_exclusive_bar(pci_dev); } diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h index 917bcc5..01005e7 100644 --- a/hw/virtio/virtio-pci.h +++ b/hw/virtio/virtio-pci.h @@ -84,6 +84,11 @@ struct VirtIOPCIProxy { PCIDevice pci_dev; VirtIODevice *vdev; MemoryRegion bar; + MemoryRegion config_bar; + MemoryRegion config_common; + MemoryRegion config_isr; + MemoryRegion config_notify; + MemoryRegion config_device; uint32_t flags; uint32_t class_code; uint32_t nvectors; @@ -93,6 +98,8 @@ struct VirtIOPCIProxy { VirtIOIRQFD *vector_irqfd; int nvqs_with_notifiers; VirtioBusState bus; + unsigned device_feature_select; + unsigned guest_feature_select; }; @@ -203,4 +210,52 @@ struct VirtIORngPCI { /* Virtio ABI version, if we increment this, we break the guest driver. */ #define VIRTIO_PCI_ABI_VERSION 0 +/* IDs for different capabilities. Must all exist. */ +/* Common configuration */ +#define VIRTIO_PCI_CAP_COMMON_CFG 1 +/* Notifications */ +#define VIRTIO_PCI_CAP_NOTIFY_CFG 2 +/* ISR access */ +#define VIRTIO_PCI_CAP_ISR_CFG 3 +/* Device specific confiuration */ +#define VIRTIO_PCI_CAP_DEVICE_CFG 4 + +/* This is the PCI capability header: */ +struct virtio_pci_cap { + uint8_t cap_vndr; /* Generic PCI field: PCI_CAP_ID_VNDR */ + uint8_t cap_next; /* Generic PCI field: next ptr. */ + uint8_t cap_length; /* Generic PCI field: capability length. */ + uint8_t cfg_type; /* One of the VIRTIO_PCI_CAP_*_CFG. */ + uint8_t bar; /* Where to find it. */ + uint32_t offset; /* Offset within bar. */ + uint32_t length; /* Length. */ +}; + +struct virtio_pci_notify_cap { + struct virtio_pci_cap cap; + uint32_t notify_off_multiplier; /* Multiplier for queue_notify_off. */ +}; + +/* Fields in VIRTIO_PCI_CAP_COMMON_CFG: */ +struct virtio_pci_common_cfg { + /* About the whole device. */ + uint32_t device_feature_select; /* read-write */ + uint32_t device_feature; /* read-only */ + uint32_t guest_feature_select; /* read-write */ + uint32_t guest_feature; /* read-only */ + uint16_t msix_config; /* read-write */ + uint16_t num_queues; /* read-only */ + uint8_t device_status; /* read-write */ + uint8_t unused1; + + /* About a specific virtqueue. */ + uint16_t queue_select; /* read-write */ + uint16_t queue_size; /* read-write, power of 2. */ + uint16_t queue_msix_vector; /* read-write */ + uint16_t queue_enable; /* read-write */ + uint16_t queue_notify_off; /* read-only */ + uint64_t queue_desc; /* read-write */ + uint64_t queue_avail; /* read-write */ + uint64_t queue_used; /* read-write */ +}; #endif diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 8176c14..e54d692 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -672,6 +672,11 @@ int virtio_queue_get_num(VirtIODevice *vdev, int n) return vdev->vq[n].vring.num; } +void virtio_queue_set_num(VirtIODevice *vdev, int n, int num) +{ + vdev->vq[n].vring.num = num; +} + int virtio_queue_get_id(VirtQueue *vq) { VirtIODevice *vdev = vq->vdev; @@ -987,6 +992,21 @@ hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n) return vdev->vq[n].vring.used; } +void virtio_queue_set_desc_addr(VirtIODevice *vdev, int n, hwaddr addr) +{ + vdev->vq[n].vring.desc = addr; +} + +void virtio_queue_set_avail_addr(VirtIODevice *vdev, int n, hwaddr addr) +{ + vdev->vq[n].vring.avail = addr; +} + +void virtio_queue_set_used_addr(VirtIODevice *vdev, int n, hwaddr addr) +{ + vdev->vq[n].vring.used = addr; +} + hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n) { return vdev->vq[n].vring.desc; diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index a6c5c53..d056d58 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -199,6 +199,7 @@ void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data); void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr); hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n); int virtio_queue_get_num(VirtIODevice *vdev, int n); +void virtio_queue_set_num(VirtIODevice *vdev, int n, int num); void virtio_queue_notify(VirtIODevice *vdev, int n); uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector); @@ -226,6 +227,9 @@ typedef struct VirtIORNGConf VirtIORNGConf; hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n); hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n); hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n); +void virtio_queue_set_desc_addr(VirtIODevice *vdev, int n, hwaddr addr); +void virtio_queue_set_avail_addr(VirtIODevice *vdev, int n, hwaddr addr); +void virtio_queue_set_used_addr(VirtIODevice *vdev, int n, hwaddr addr); hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n); hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n); hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n); -- MST
Anthony Liguori
2013-May-28 17:15 UTC
[PATCH RFC] virtio-pci: new config layout: using memory BAR
"Michael S. Tsirkin" <mst at redhat.com> writes:> This adds support for new config, and is designed to work with > the new layout code in Rusty's new layout branch. > > At the moment all fields are in the same memory BAR (bar 2). > This will be used to test performance and compare > memory, io and hypercall latency. > > Compiles but does not work yet. > Migration isn't handled yet. > > It's not clear what do queue_enable/queue_disable > fields do, not yet implemented. > > Gateway for config access with config cycles > not yet implemented. > > Sending out for early review/flames. > > Signed-off-by: Michael S. Tsirkin <mst at redhat.com> > --- > hw/virtio/virtio-pci.c | 393 +++++++++++++++++++++++++++++++++++++++++++-- > hw/virtio/virtio-pci.h | 55 +++++++ > hw/virtio/virtio.c | 20 +++ > include/hw/virtio/virtio.h | 4 + > 4 files changed, 458 insertions(+), 14 deletions(-) > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index 752991a..f4db224 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -259,6 +259,26 @@ static void virtio_pci_stop_ioeventfd(VirtIOPCIProxy *proxy) > proxy->ioeventfd_started = false; > } > > +static void virtio_pci_set_status(VirtIOPCIProxy *proxy, uint8_t val) > +{ > + VirtIODevice *vdev = proxy->vdev; > + > + if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > + virtio_pci_stop_ioeventfd(proxy); > + } > + > + virtio_set_status(vdev, val & 0xFF); > + > + if (val & VIRTIO_CONFIG_S_DRIVER_OK) { > + virtio_pci_start_ioeventfd(proxy); > + } > + > + if (vdev->status == 0) { > + virtio_reset(proxy->vdev); > + msix_unuse_all_vectors(&proxy->pci_dev); > + } > +} > + > static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) > { > VirtIOPCIProxy *proxy = opaque; > @@ -293,20 +313,7 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val) > } > break; > case VIRTIO_PCI_STATUS: > - if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > - virtio_pci_stop_ioeventfd(proxy); > - } > - > - virtio_set_status(vdev, val & 0xFF); > - > - if (val & VIRTIO_CONFIG_S_DRIVER_OK) { > - virtio_pci_start_ioeventfd(proxy); > - } > - > - if (vdev->status == 0) { > - virtio_reset(proxy->vdev); > - msix_unuse_all_vectors(&proxy->pci_dev); > - } > + virtio_pci_set_status(proxy, val); > > /* Linux before 2.6.34 sets the device as OK without enabling > the PCI device bus master bit. In this case we need to disable > @@ -455,6 +462,226 @@ static void virtio_pci_config_write(void *opaque, hwaddr addr, > } > } > > +static uint64_t virtio_pci_config_common_read(void *opaque, hwaddr addr, > + unsigned size) > +{ > + VirtIOPCIProxy *proxy = opaque; > + VirtIODevice *vdev = proxy->vdev; > + > + uint64_t low = 0xffffffffull; > + > + switch (addr) { > + case offsetof(struct virtio_pci_common_cfg, device_feature_select): > + return proxy->device_feature_select;Oh dear no... Please use defines like the rest of QEMU.>From a QEMU pov, take a look at:https://github.com/aliguori/qemu/commit/587c35c1a3fe90f6af0f97927047ef4d3182a659 And: https://github.com/aliguori/qemu/commit/01ba80a23cf2eb1e15056f82b44b94ec381565cb Which lets virtio-pci be subclassable and then remaps the config space to BAR2. Haven't looked at the proposed new ring layout yet. Regards, Anthony Liguori> + case offsetof(struct virtio_pci_common_cfg, device_feature): > + /* TODO: 64-bit features */ > + return proxy->device_feature_select ? 0 : proxy->host_features; > + case offsetof(struct virtio_pci_common_cfg, guest_feature_select): > + return proxy->guest_feature_select; > + case offsetof(struct virtio_pci_common_cfg, guest_feature): > + /* TODO: 64-bit features */ > + return proxy->guest_feature_select ? 0 : vdev->guest_features; > + case offsetof(struct virtio_pci_common_cfg, msix_config): > + return vdev->config_vector; > + case offsetof(struct virtio_pci_common_cfg, num_queues): > + /* TODO: more exact limit? */ > + return VIRTIO_PCI_QUEUE_MAX; > + case offsetof(struct virtio_pci_common_cfg, device_status): > + return vdev->status; > + > + /* About a specific virtqueue. */ > + case offsetof(struct virtio_pci_common_cfg, queue_select): > + return vdev->queue_sel; > + case offsetof(struct virtio_pci_common_cfg, queue_size): > + return virtio_queue_get_num(vdev, vdev->queue_sel); > + case offsetof(struct virtio_pci_common_cfg, queue_msix_vector): > + return virtio_queue_vector(vdev, vdev->queue_sel); > + case offsetof(struct virtio_pci_common_cfg, queue_enable): > + /* TODO */ > + return 0; > + case offsetof(struct virtio_pci_common_cfg, queue_notify_off): > + return vdev->queue_sel; > + case offsetof(struct virtio_pci_common_cfg, queue_desc): > + return virtio_queue_get_desc_addr(vdev, vdev->queue_sel) & low; > + case offsetof(struct virtio_pci_common_cfg, queue_desc) + 4: > + return virtio_queue_get_desc_addr(vdev, vdev->queue_sel) >> 32; > + case offsetof(struct virtio_pci_common_cfg, queue_avail): > + return virtio_queue_get_avail_addr(vdev, vdev->queue_sel) & low; > + case offsetof(struct virtio_pci_common_cfg, queue_avail) + 4: > + return virtio_queue_get_avail_addr(vdev, vdev->queue_sel) >> 32; > + case offsetof(struct virtio_pci_common_cfg, queue_used): > + return virtio_queue_get_used_addr(vdev, vdev->queue_sel) & low; > + case offsetof(struct virtio_pci_common_cfg, queue_used) + 4: > + return virtio_queue_get_used_addr(vdev, vdev->queue_sel) >> 32; > + default: > + return 0; > + } > +} > + > +static void virtio_pci_config_common_write(void *opaque, hwaddr addr, > + uint64_t val, unsigned size) > +{ > + VirtIOPCIProxy *proxy = opaque; > + VirtIODevice *vdev = proxy->vdev; > + > + uint64_t low = 0xffffffffull; > + uint64_t high = ~low; > + > + switch (addr) { > + case offsetof(struct virtio_pci_common_cfg, device_feature_select): > + proxy->device_feature_select = val; > + break; > + case offsetof(struct virtio_pci_common_cfg, device_feature): > + break; > + case offsetof(struct virtio_pci_common_cfg, guest_feature_select): > + proxy->guest_feature_select = val; > + break; > + case offsetof(struct virtio_pci_common_cfg, guest_feature): > + /* TODO: 64-bit features */ > + if (!proxy->guest_feature_select) { > + virtio_set_features(vdev, val); > + } > + break; > + case offsetof(struct virtio_pci_common_cfg, msix_config): > + vdev->config_vector = val; > + break; > + case offsetof(struct virtio_pci_common_cfg, num_queues): > + break; > + case offsetof(struct virtio_pci_common_cfg, device_status): > + virtio_pci_set_status(proxy, val); > + break; > + /* About a specific virtqueue. */ > + case offsetof(struct virtio_pci_common_cfg, queue_select): > + assert(val < VIRTIO_PCI_QUEUE_MAX); > + vdev->queue_sel = val; > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_size): > + assert(val && val < 0x8ffff && !(val & (val - 1))); > + virtio_queue_set_num(vdev, vdev->queue_sel, val); > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_msix_vector): > + virtio_queue_set_vector(vdev, vdev->queue_sel, val); > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_enable): > + /* TODO */ > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_notify_off): > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_desc): > + val &= low; > + val |= virtio_queue_get_desc_addr(vdev, vdev->queue_sel) & high; > + virtio_queue_set_desc_addr(vdev, vdev->queue_sel, val); > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_desc) + 4: > + val = val << 32; > + val |= virtio_queue_get_desc_addr(vdev, vdev->queue_sel) & low; > + virtio_queue_set_desc_addr(vdev, vdev->queue_sel, val); > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_avail): > + val &= low; > + val |= virtio_queue_get_avail_addr(vdev, vdev->queue_sel) & high; > + virtio_queue_set_avail_addr(vdev, vdev->queue_sel, val); > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_avail) + 4: > + val = val << 32; > + val |= virtio_queue_get_avail_addr(vdev, vdev->queue_sel) & low; > + virtio_queue_set_avail_addr(vdev, vdev->queue_sel, val); > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_used): > + val &= low; > + val |= virtio_queue_get_used_addr(vdev, vdev->queue_sel) & high; > + virtio_queue_set_used_addr(vdev, vdev->queue_sel, val); > + break; > + case offsetof(struct virtio_pci_common_cfg, queue_used) + 4: > + val = val << 32; > + val |= virtio_queue_get_used_addr(vdev, vdev->queue_sel) & low; > + virtio_queue_set_used_addr(vdev, vdev->queue_sel, val); > + break; > + default: > + break; > + } > +} > + > +static uint64_t virtio_pci_config_isr_read(void *opaque, hwaddr addr, > + unsigned size) > +{ > + VirtIOPCIProxy *proxy = opaque; > + VirtIODevice *vdev = proxy->vdev; > + uint8_t ret; > + > + /* reading from the ISR also clears it. */ > + ret = vdev->isr; > + vdev->isr = 0; > + qemu_set_irq(proxy->pci_dev.irq[0], 0); > + return ret; > +} > + > +static void virtio_pci_config_isr_write(void *opaque, hwaddr addr, > + uint64_t val, unsigned size) > +{ > +} > + > +static uint64_t virtio_pci_config_notify_read(void *opaque, hwaddr addr, > + unsigned size) > +{ > + return 0; > +} > + > +static void virtio_pci_config_notify_write(void *opaque, hwaddr addr, > + uint64_t val, unsigned size) > +{ > + VirtIOPCIProxy *proxy = opaque; > + VirtIODevice *vdev = proxy->vdev; > + if (val < VIRTIO_PCI_QUEUE_MAX) { > + virtio_queue_notify(vdev, val); > + } > +} > + > +static uint64_t virtio_pci_config_device_read(void *opaque, hwaddr addr, > + unsigned size) > +{ > + VirtIOPCIProxy *proxy = opaque; > + uint64_t val = 0; > + switch (size) { > + case 1: > + val = virtio_config_readb(proxy->vdev, addr); > + break; > + case 2: > + val = virtio_config_readw(proxy->vdev, addr); > + break; > + case 4: > + /* Most devices don't have 64 bit config fields. > + * Block is an exception: first 8 bytes include > + * a 64 bit capacity field. > + */ > + if (VIRTIO_HOST_IS_BIG_ENDIAN && > + proxy->vdev->device_id == VIRTIO_ID_BLOCK && addr < 8) { > + /* Swap first two words */ > + addr ^= 0x4; > + } > + val = virtio_config_readl(proxy->vdev, addr); > + break; > + } > + return val; > +} > + > +static void virtio_pci_config_device_write(void *opaque, hwaddr addr, > + uint64_t val, unsigned size) > +{ > + VirtIOPCIProxy *proxy = opaque; > + switch (size) { > + case 1: > + virtio_config_writeb(proxy->vdev, addr, val); > + break; > + case 2: > + virtio_config_writew(proxy->vdev, addr, val); > + break; > + case 4: > + virtio_config_writel(proxy->vdev, addr, val); > + break; > + } > +} > + > static const MemoryRegionOps virtio_pci_config_ops = { > .read = virtio_pci_config_read, > .write = virtio_pci_config_write, > @@ -465,6 +692,46 @@ static const MemoryRegionOps virtio_pci_config_ops = { > .endianness = DEVICE_LITTLE_ENDIAN, > }; > > +static const MemoryRegionOps virtio_pci_config_common_ops = { > + .read = virtio_pci_config_common_read, > + .write = virtio_pci_config_common_write, > + .impl = { > + .min_access_size = 1, > + .max_access_size = 4, > + }, > + .endianness = DEVICE_LITTLE_ENDIAN, > +}; > + > +static const MemoryRegionOps virtio_pci_config_isr_ops = { > + .read = virtio_pci_config_isr_read, > + .write = virtio_pci_config_isr_write, > + .impl = { > + .min_access_size = 1, > + .max_access_size = 1, > + }, > + .endianness = DEVICE_LITTLE_ENDIAN, > +}; > + > +static const MemoryRegionOps virtio_pci_config_notify_ops = { > + .read = virtio_pci_config_notify_read, > + .write = virtio_pci_config_notify_write, > + .impl = { > + .min_access_size = 2, > + .max_access_size = 2, > + }, > + .endianness = DEVICE_LITTLE_ENDIAN, > +}; > + > +static const MemoryRegionOps virtio_pci_config_device_ops = { > + .read = virtio_pci_config_device_read, > + .write = virtio_pci_config_device_write, > + .impl = { > + .min_access_size = 1, > + .max_access_size = 4, > + }, > + .endianness = DEVICE_LITTLE_ENDIAN, > +}; > + > static void virtio_write_config(PCIDevice *pci_dev, uint32_t address, > uint32_t val, int len) > { > @@ -949,11 +1216,49 @@ static const TypeInfo virtio_9p_pci_info = { > * virtio-pci: This is the PCIDevice which has a virtio-pci-bus. > */ > > +#define VIRTIO_PCI_CONFIG_BAR_NUM 2 > + > +static void *virtio_pci_cap_add(VirtIOPCIProxy *proxy, > + const char *name, > + MemoryRegion *reg, > + const MemoryRegionOps *ops, > + unsigned offset, > + unsigned size, > + unsigned cap_type, > + unsigned cap_length) > +{ > + struct virtio_pci_cap *cap; > + int c; > + memory_region_init_io(reg, ops, proxy, name, size); > + memory_region_add_subregion(&proxy->config_bar, offset, reg); > + > + if (!cap_length) { > + cap_length = sizeof *cap; > + } > + c = pci_add_capability(&proxy->pci_dev, PCI_CAP_ID_VNDR, 0, cap_length); > + assert(c > 0); > + cap = (void *)proxy->pci_dev.config + c; > + cap->cap_length = cap_length; > + cap->cfg_type = cap_type; > + cap->bar = VIRTIO_PCI_CONFIG_BAR_NUM; > + cap->offset = offset; > + cap->length = size; > + > + return cap; > +} > + > +static void virtio_pci_cap_del(VirtIOPCIProxy *proxy, MemoryRegion *reg) > +{ > + memory_region_del_subregion(&proxy->config_bar, reg); > + memory_region_destroy(reg); > +} > + > /* This is called by virtio-bus just after the device is plugged. */ > static void virtio_pci_device_plugged(DeviceState *d) > { > VirtIOPCIProxy *proxy = VIRTIO_PCI(d); > VirtioBusState *bus = &proxy->bus; > + struct virtio_pci_notify_cap *notify_cap; > uint8_t *config; > uint32_t size; > > @@ -986,6 +1291,59 @@ static void virtio_pci_device_plugged(DeviceState *d) > pci_register_bar(&proxy->pci_dev, 0, PCI_BASE_ADDRESS_SPACE_IO, > &proxy->bar); > > + /* New config layout */ > + /* Four capabilities: common, notify, isr, device cfg */ > +#define VIRTIO_PCI_CONFIG_BAR_SIZE 0x1000 > +#define VIRTIO_PCI_CONFIG_COMMON 0x0 > +#define VIRTIO_PCI_CONFIG_NOTIFY 0x100 > +#define VIRTIO_PCI_CONFIG_ISR 0x200 > +#define VIRTIO_PCI_CONFIG_DEVICE 0x300 > + > + /* Make sure we left enough space for all vqs */ > + assert(VIRTIO_PCI_CONFIG_ISR - VIRTIO_PCI_CONFIG_NOTIFY >> + VIRTIO_PCI_QUEUE_MAX * 2); > + assert(VIRTIO_PCI_CONFIG_BAR_SIZE - VIRTIO_PCI_CONFIG_DEVICE >> + proxy->vdev->config_len); > + > + memory_region_init(&proxy->config_bar, "virtio-pci-config", > + VIRTIO_PCI_CONFIG_BAR_SIZE); > + > + virtio_pci_cap_add(proxy, "virtio-pci-common", > + &proxy->config_common, > + &virtio_pci_config_common_ops, > + VIRTIO_PCI_CONFIG_COMMON, > + sizeof(struct virtio_pci_common_cfg), > + VIRTIO_PCI_CAP_COMMON_CFG, > + 0); > + notify_cap = virtio_pci_cap_add(proxy, "virtio-pci-notify", > + &proxy->config_notify, > + &virtio_pci_config_notify_ops, > + VIRTIO_PCI_CONFIG_NOTIFY, > + VIRTIO_PCI_QUEUE_MAX * 2, > + VIRTIO_PCI_CAP_NOTIFY_CFG, > + sizeof *notify_cap); > + notify_cap->notify_off_multiplier = 0x2; > + virtio_pci_cap_add(proxy, "virtio-pci-isr", > + &proxy->config_isr, > + &virtio_pci_config_isr_ops, > + VIRTIO_PCI_CONFIG_ISR, > + 0x1, > + VIRTIO_PCI_CAP_ISR_CFG, > + 0); > + if (proxy->vdev->config_len) { > + virtio_pci_cap_add(proxy, "virtio-pci-device", > + &proxy->config_device, > + &virtio_pci_config_device_ops, > + VIRTIO_PCI_CONFIG_DEVICE, > + proxy->vdev->config_len, > + VIRTIO_PCI_CAP_DEVICE_CFG, > + 0); > + } > + > + pci_register_bar(&proxy->pci_dev, VIRTIO_PCI_CONFIG_BAR_NUM, > + PCI_BASE_ADDRESS_SPACE_MEMORY, > + &proxy->config_bar); > + > if (!kvm_has_many_ioeventfds()) { > proxy->flags &= ~VIRTIO_PCI_FLAG_USE_IOEVENTFD; > } > @@ -1012,6 +1370,13 @@ static void virtio_pci_exit(PCIDevice *pci_dev) > VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev); > virtio_pci_stop_ioeventfd(proxy); > memory_region_destroy(&proxy->bar); > + virtio_pci_cap_del(proxy, &proxy->config_common); > + virtio_pci_cap_del(proxy, &proxy->config_notify); > + virtio_pci_cap_del(proxy, &proxy->config_isr); > + if (&proxy->vdev->config_len) { > + virtio_pci_cap_del(proxy, &proxy->config_device); > + } > + memory_region_destroy(&proxy->config_bar); > msix_uninit_exclusive_bar(pci_dev); > } > > diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h > index 917bcc5..01005e7 100644 > --- a/hw/virtio/virtio-pci.h > +++ b/hw/virtio/virtio-pci.h > @@ -84,6 +84,11 @@ struct VirtIOPCIProxy { > PCIDevice pci_dev; > VirtIODevice *vdev; > MemoryRegion bar; > + MemoryRegion config_bar; > + MemoryRegion config_common; > + MemoryRegion config_isr; > + MemoryRegion config_notify; > + MemoryRegion config_device; > uint32_t flags; > uint32_t class_code; > uint32_t nvectors; > @@ -93,6 +98,8 @@ struct VirtIOPCIProxy { > VirtIOIRQFD *vector_irqfd; > int nvqs_with_notifiers; > VirtioBusState bus; > + unsigned device_feature_select; > + unsigned guest_feature_select; > }; > > > @@ -203,4 +210,52 @@ struct VirtIORngPCI { > /* Virtio ABI version, if we increment this, we break the guest driver. */ > #define VIRTIO_PCI_ABI_VERSION 0 > > +/* IDs for different capabilities. Must all exist. */ > +/* Common configuration */ > +#define VIRTIO_PCI_CAP_COMMON_CFG 1 > +/* Notifications */ > +#define VIRTIO_PCI_CAP_NOTIFY_CFG 2 > +/* ISR access */ > +#define VIRTIO_PCI_CAP_ISR_CFG 3 > +/* Device specific confiuration */ > +#define VIRTIO_PCI_CAP_DEVICE_CFG 4 > + > +/* This is the PCI capability header: */ > +struct virtio_pci_cap { > + uint8_t cap_vndr; /* Generic PCI field: PCI_CAP_ID_VNDR */ > + uint8_t cap_next; /* Generic PCI field: next ptr. */ > + uint8_t cap_length; /* Generic PCI field: capability length. */ > + uint8_t cfg_type; /* One of the VIRTIO_PCI_CAP_*_CFG. */ > + uint8_t bar; /* Where to find it. */ > + uint32_t offset; /* Offset within bar. */ > + uint32_t length; /* Length. */ > +}; > + > +struct virtio_pci_notify_cap { > + struct virtio_pci_cap cap; > + uint32_t notify_off_multiplier; /* Multiplier for queue_notify_off. */ > +}; > + > +/* Fields in VIRTIO_PCI_CAP_COMMON_CFG: */ > +struct virtio_pci_common_cfg { > + /* About the whole device. */ > + uint32_t device_feature_select; /* read-write */ > + uint32_t device_feature; /* read-only */ > + uint32_t guest_feature_select; /* read-write */ > + uint32_t guest_feature; /* read-only */ > + uint16_t msix_config; /* read-write */ > + uint16_t num_queues; /* read-only */ > + uint8_t device_status; /* read-write */ > + uint8_t unused1; > + > + /* About a specific virtqueue. */ > + uint16_t queue_select; /* read-write */ > + uint16_t queue_size; /* read-write, power of 2. */ > + uint16_t queue_msix_vector; /* read-write */ > + uint16_t queue_enable; /* read-write */ > + uint16_t queue_notify_off; /* read-only */ > + uint64_t queue_desc; /* read-write */ > + uint64_t queue_avail; /* read-write */ > + uint64_t queue_used; /* read-write */ > +}; > #endif > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 8176c14..e54d692 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -672,6 +672,11 @@ int virtio_queue_get_num(VirtIODevice *vdev, int n) > return vdev->vq[n].vring.num; > } > > +void virtio_queue_set_num(VirtIODevice *vdev, int n, int num) > +{ > + vdev->vq[n].vring.num = num; > +} > + > int virtio_queue_get_id(VirtQueue *vq) > { > VirtIODevice *vdev = vq->vdev; > @@ -987,6 +992,21 @@ hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n) > return vdev->vq[n].vring.used; > } > > +void virtio_queue_set_desc_addr(VirtIODevice *vdev, int n, hwaddr addr) > +{ > + vdev->vq[n].vring.desc = addr; > +} > + > +void virtio_queue_set_avail_addr(VirtIODevice *vdev, int n, hwaddr addr) > +{ > + vdev->vq[n].vring.avail = addr; > +} > + > +void virtio_queue_set_used_addr(VirtIODevice *vdev, int n, hwaddr addr) > +{ > + vdev->vq[n].vring.used = addr; > +} > + > hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n) > { > return vdev->vq[n].vring.desc; > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index a6c5c53..d056d58 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -199,6 +199,7 @@ void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data); > void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr); > hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n); > int virtio_queue_get_num(VirtIODevice *vdev, int n); > +void virtio_queue_set_num(VirtIODevice *vdev, int n, int num); > void virtio_queue_notify(VirtIODevice *vdev, int n); > uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); > void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector); > @@ -226,6 +227,9 @@ typedef struct VirtIORNGConf VirtIORNGConf; > hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n); > hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n); > hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n); > +void virtio_queue_set_desc_addr(VirtIODevice *vdev, int n, hwaddr addr); > +void virtio_queue_set_avail_addr(VirtIODevice *vdev, int n, hwaddr addr); > +void virtio_queue_set_used_addr(VirtIODevice *vdev, int n, hwaddr addr); > hwaddr virtio_queue_get_ring_addr(VirtIODevice *vdev, int n); > hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n); > hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n); > -- > MST > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo at vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
Michael S. Tsirkin
2013-May-28 17:32 UTC
[PATCH RFC] virtio-pci: new config layout: using memory BAR
On Tue, May 28, 2013 at 12:15:16PM -0500, Anthony Liguori wrote:> > @@ -455,6 +462,226 @@ static void virtio_pci_config_write(void *opaque, hwaddr addr, > > } > > } > > > > +static uint64_t virtio_pci_config_common_read(void *opaque, hwaddr addr, > > + unsigned size) > > +{ > > + VirtIOPCIProxy *proxy = opaque; > > + VirtIODevice *vdev = proxy->vdev; > > + > > + uint64_t low = 0xffffffffull; > > + > > + switch (addr) { > > + case offsetof(struct virtio_pci_common_cfg, device_feature_select): > > + return proxy->device_feature_select; > > Oh dear no... Please use defines like the rest of QEMU.Any good reason not to use offsetof? I see about 138 examples in qemu. Anyway, that's the way Rusty wrote it in the kernel header - I started with defines. If you convince Rusty to switch I can switch too, but I prefer reusing same structures as linux even if for now I've given up on reusing same headers.> >From a QEMU pov, take a look at: > > https://github.com/aliguori/qemu/commit/587c35c1a3fe90f6af0f97927047ef4d3182a659 > > And: > > https://github.com/aliguori/qemu/commit/01ba80a23cf2eb1e15056f82b44b94ec381565cb > > Which lets virtio-pci be subclassable and then remaps the config space to > BAR2.Interesting. Have the spec anywhere? You are saying this is going to conflict because of BAR2 usage, yes? So let's only do this virtio-fb only for new layout, so we don't need to maintain compatibility. In particular, we are working on making memory BAR access fast for virtio devices in a generic way. At the moment they are measureably slower than PIO on x86.> Haven't looked at the proposed new ring layout yet. > > Regards,No new ring layout. It's new config layout. -- MST
Rusty Russell
2013-May-29 04:31 UTC
[PATCH RFC] virtio-pci: new config layout: using memory BAR
Anthony Liguori <aliguori at us.ibm.com> writes:> "Michael S. Tsirkin" <mst at redhat.com> writes: >> + case offsetof(struct virtio_pci_common_cfg, device_feature_select): >> + return proxy->device_feature_select; > > Oh dear no... Please use defines like the rest of QEMU.It is pretty ugly. Yet the structure definitions are descriptive, capturing layout, size and endianness in natural a format readable by any C programmer. So AFAICT the question is, do we put the required #define VIRTIO_PCI_CFG_FEATURE_SEL \ (offsetof(struct virtio_pci_common_cfg, device_feature_select)) etc. in the kernel headers or qemu?> Haven't looked at the proposed new ring layout yet.No change, but there's an open question on whether we should nail it to little endian (or define the endian by the transport). Of course, I can't rule out that the 1.0 standard *may* decide to frob the ring layout somehow, but I'd think it would require a compelling reason. I suggest that's 2.0 material... Cheers, Rusty.
Seemingly Similar Threads
- [PATCH RFC] virtio-pci: new config layout: using memory BAR
- [PATCH RFC] virtio-pci: new config layout: using memory BAR
- [PATCH RFC] virtio-pci: new config layout: using memory BAR
- [RFC 7/11] virtio_pci: new, capability-aware driver.
- [PATCH RFC] virtio-pci: new config layout: using memory BAR