Message ID | 1473256389-1185-1-git-send-email-marcel@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Wed, Sep 07, 2016 at 04:53:09PM +0300, Marcel Apfelbaum wrote: > Currently each VQ Notification Virtio Capability is allocated > on a different page. The idea is to enable split drivers within > guests, however there are no known plans to do that. > The allocation will result in a 8MB BAR, more than various > guest firmwares pre-allocates for PCI Bridges hotplug process. > > Reserve 4 bytes per VQ by default and add a new parameter > "page-per-vq" to be used with split drivers. > > Signed-off-by: Marcel Apfelbaum <marcel@redhat.com> > --- > Hi, > > To be applied on top of: > [PATCH v5 1/2] pc: Add 2.8 machine (http://patchwork.ozlabs.org/patch/666812/) > > Thanks, > Marcel > > hw/virtio/virtio-pci.c | 18 +++++++++++------- > hw/virtio/virtio-pci.h | 6 ++++++ > include/hw/compat.h | 6 +++++- > 3 files changed, 22 insertions(+), 8 deletions(-) > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index 755f921..25e7ffa 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -307,7 +307,7 @@ static int virtio_pci_ioeventfd_assign(DeviceState *d, EventNotifier *notifier, > MemoryRegion *modern_mr = &proxy->notify.mr; > MemoryRegion *modern_notify_mr = &proxy->notify_pio.mr; > MemoryRegion *legacy_mr = &proxy->bar; > - hwaddr modern_addr = QEMU_VIRTIO_PCI_QUEUE_MEM_MULT * > + hwaddr modern_addr = proxy->queue_mem_mult * > virtio_get_queue_index(vq); > hwaddr legacy_addr = VIRTIO_PCI_QUEUE_NOTIFY; > > @@ -1370,7 +1370,8 @@ static void virtio_pci_notify_write(void *opaque, hwaddr addr, > uint64_t val, unsigned size) > { > VirtIODevice *vdev = opaque; > - unsigned queue = addr / QEMU_VIRTIO_PCI_QUEUE_MEM_MULT; > + VirtIOPCIProxy *proxy = VIRTIO_PCI(DEVICE(vdev)->parent_bus->parent); > + unsigned queue = addr / proxy->queue_mem_mult; > > if (queue < VIRTIO_QUEUE_MAX) { > virtio_queue_notify(vdev, queue); > @@ -1609,7 +1610,7 @@ static void virtio_pci_device_plugged(DeviceState *d, Error **errp) > struct virtio_pci_notify_cap notify = { > .cap.cap_len = sizeof notify, > .notify_off_multiplier = > - cpu_to_le32(QEMU_VIRTIO_PCI_QUEUE_MEM_MULT), > + cpu_to_le32(proxy->queue_mem_mult), > }; > struct virtio_pci_cfg_cap cfg = { > .cap.cap_len = sizeof cfg, > @@ -1717,6 +1718,9 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) > bool pcie_port = pci_bus_is_express(pci_dev->bus) && > !pci_bus_is_root(pci_dev->bus); > > + proxy->queue_mem_mult = (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ) ? > + QEMU_VIRTIO_PCI_QUEUE_MEM_MULT : 4; > + > /* > * virtio pci bar layout used by default. > * subclasses can re-arrange things if needed. > @@ -1744,8 +1748,7 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) > proxy->device.type = VIRTIO_PCI_CAP_DEVICE_CFG; > > proxy->notify.offset = 0x3000; > - proxy->notify.size = > - QEMU_VIRTIO_PCI_QUEUE_MEM_MULT * VIRTIO_QUEUE_MAX; > + proxy->notify.size = proxy->queue_mem_mult * VIRTIO_QUEUE_MAX; > proxy->notify.type = VIRTIO_PCI_CAP_NOTIFY_CFG; > > proxy->notify_pio.offset = 0x0; > @@ -1754,8 +1757,7 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) > > /* subclasses can enforce modern, so do this unconditionally */ > memory_region_init(&proxy->modern_bar, OBJECT(proxy), "virtio-pci", > - 2 * QEMU_VIRTIO_PCI_QUEUE_MEM_MULT * > - VIRTIO_QUEUE_MAX); Maybe add /* PCI BAR regions must be powers of 2 */ > + pow2ceil(proxy->notify.offset + proxy->notify.size)); > > memory_region_init_alias(&proxy->modern_cfg, > OBJECT(proxy), > @@ -1833,6 +1835,8 @@ static Property virtio_pci_properties[] = { > VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY_BIT, false), > DEFINE_PROP_BIT("x-disable-pcie", VirtIOPCIProxy, flags, > VIRTIO_PCI_FLAG_DISABLE_PCIE_BIT, false), > + DEFINE_PROP_BIT("page-per-vq", VirtIOPCIProxy, flags, > + VIRTIO_PCI_FLAG_PAGE_PER_VQ_BIT, false), > DEFINE_PROP_END_OF_LIST(), > }; > > diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h > index 25fbf8a..0fd0d37 100644 > --- a/hw/virtio/virtio-pci.h > +++ b/hw/virtio/virtio-pci.h > @@ -64,6 +64,7 @@ enum { > VIRTIO_PCI_FLAG_MIGRATE_EXTRA_BIT, > VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY_BIT, > VIRTIO_PCI_FLAG_DISABLE_PCIE_BIT, > + VIRTIO_PCI_FLAG_PAGE_PER_VQ_BIT, > }; > > /* Need to activate work-arounds for buggy guests at vmstate load. */ > @@ -84,6 +85,10 @@ enum { > #define VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY \ > (1 << VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY_BIT) > > +/* page per vq flag to be used by split drivers within guests */ > +#define VIRTIO_PCI_FLAG_PAGE_PER_VQ \ > + (1 << VIRTIO_PCI_FLAG_PAGE_PER_VQ_BIT) > + > typedef struct { > MSIMessage msg; > int virq; > @@ -138,6 +143,7 @@ struct VirtIOPCIProxy { > uint32_t msix_bar; > uint32_t modern_io_bar; > uint32_t modern_mem_bar; > + int queue_mem_mult; > int config_cap; > uint32_t flags; > bool disable_modern; I would rather use wrapper functions to calculate it, to avoid duplicating data. E.g. static inline int virtio_pci_queue_mem_mult(struct VirtIOPCIProxy *) { return (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ) ? QEMU_VIRTIO_PCI_QUEUE_MEM_MULT : 4; } Otherwise, looks fine. > diff --git a/include/hw/compat.h b/include/hw/compat.h > index 08dd4fb..a1d6694 100644 > --- a/include/hw/compat.h > +++ b/include/hw/compat.h > @@ -2,7 +2,11 @@ > #define HW_COMPAT_H > > #define HW_COMPAT_2_7 \ > - /* empty */ > + {\ > + .driver = "virtio-pci",\ > + .property = "page-per-vq",\ > + .value = "on",\ > + }, > > #define HW_COMPAT_2_6 \ > {\ > -- > 2.5.5
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index 755f921..25e7ffa 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -307,7 +307,7 @@ static int virtio_pci_ioeventfd_assign(DeviceState *d, EventNotifier *notifier, MemoryRegion *modern_mr = &proxy->notify.mr; MemoryRegion *modern_notify_mr = &proxy->notify_pio.mr; MemoryRegion *legacy_mr = &proxy->bar; - hwaddr modern_addr = QEMU_VIRTIO_PCI_QUEUE_MEM_MULT * + hwaddr modern_addr = proxy->queue_mem_mult * virtio_get_queue_index(vq); hwaddr legacy_addr = VIRTIO_PCI_QUEUE_NOTIFY; @@ -1370,7 +1370,8 @@ static void virtio_pci_notify_write(void *opaque, hwaddr addr, uint64_t val, unsigned size) { VirtIODevice *vdev = opaque; - unsigned queue = addr / QEMU_VIRTIO_PCI_QUEUE_MEM_MULT; + VirtIOPCIProxy *proxy = VIRTIO_PCI(DEVICE(vdev)->parent_bus->parent); + unsigned queue = addr / proxy->queue_mem_mult; if (queue < VIRTIO_QUEUE_MAX) { virtio_queue_notify(vdev, queue); @@ -1609,7 +1610,7 @@ static void virtio_pci_device_plugged(DeviceState *d, Error **errp) struct virtio_pci_notify_cap notify = { .cap.cap_len = sizeof notify, .notify_off_multiplier = - cpu_to_le32(QEMU_VIRTIO_PCI_QUEUE_MEM_MULT), + cpu_to_le32(proxy->queue_mem_mult), }; struct virtio_pci_cfg_cap cfg = { .cap.cap_len = sizeof cfg, @@ -1717,6 +1718,9 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) bool pcie_port = pci_bus_is_express(pci_dev->bus) && !pci_bus_is_root(pci_dev->bus); + proxy->queue_mem_mult = (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ) ? + QEMU_VIRTIO_PCI_QUEUE_MEM_MULT : 4; + /* * virtio pci bar layout used by default. * subclasses can re-arrange things if needed. @@ -1744,8 +1748,7 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) proxy->device.type = VIRTIO_PCI_CAP_DEVICE_CFG; proxy->notify.offset = 0x3000; - proxy->notify.size = - QEMU_VIRTIO_PCI_QUEUE_MEM_MULT * VIRTIO_QUEUE_MAX; + proxy->notify.size = proxy->queue_mem_mult * VIRTIO_QUEUE_MAX; proxy->notify.type = VIRTIO_PCI_CAP_NOTIFY_CFG; proxy->notify_pio.offset = 0x0; @@ -1754,8 +1757,7 @@ static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp) /* subclasses can enforce modern, so do this unconditionally */ memory_region_init(&proxy->modern_bar, OBJECT(proxy), "virtio-pci", - 2 * QEMU_VIRTIO_PCI_QUEUE_MEM_MULT * - VIRTIO_QUEUE_MAX); + pow2ceil(proxy->notify.offset + proxy->notify.size)); memory_region_init_alias(&proxy->modern_cfg, OBJECT(proxy), @@ -1833,6 +1835,8 @@ static Property virtio_pci_properties[] = { VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY_BIT, false), DEFINE_PROP_BIT("x-disable-pcie", VirtIOPCIProxy, flags, VIRTIO_PCI_FLAG_DISABLE_PCIE_BIT, false), + DEFINE_PROP_BIT("page-per-vq", VirtIOPCIProxy, flags, + VIRTIO_PCI_FLAG_PAGE_PER_VQ_BIT, false), DEFINE_PROP_END_OF_LIST(), }; diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h index 25fbf8a..0fd0d37 100644 --- a/hw/virtio/virtio-pci.h +++ b/hw/virtio/virtio-pci.h @@ -64,6 +64,7 @@ enum { VIRTIO_PCI_FLAG_MIGRATE_EXTRA_BIT, VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY_BIT, VIRTIO_PCI_FLAG_DISABLE_PCIE_BIT, + VIRTIO_PCI_FLAG_PAGE_PER_VQ_BIT, }; /* Need to activate work-arounds for buggy guests at vmstate load. */ @@ -84,6 +85,10 @@ enum { #define VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY \ (1 << VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY_BIT) +/* page per vq flag to be used by split drivers within guests */ +#define VIRTIO_PCI_FLAG_PAGE_PER_VQ \ + (1 << VIRTIO_PCI_FLAG_PAGE_PER_VQ_BIT) + typedef struct { MSIMessage msg; int virq; @@ -138,6 +143,7 @@ struct VirtIOPCIProxy { uint32_t msix_bar; uint32_t modern_io_bar; uint32_t modern_mem_bar; + int queue_mem_mult; int config_cap; uint32_t flags; bool disable_modern; diff --git a/include/hw/compat.h b/include/hw/compat.h index 08dd4fb..a1d6694 100644 --- a/include/hw/compat.h +++ b/include/hw/compat.h @@ -2,7 +2,11 @@ #define HW_COMPAT_H #define HW_COMPAT_2_7 \ - /* empty */ + {\ + .driver = "virtio-pci",\ + .property = "page-per-vq",\ + .value = "on",\ + }, #define HW_COMPAT_2_6 \ {\
Currently each VQ Notification Virtio Capability is allocated on a different page. The idea is to enable split drivers within guests, however there are no known plans to do that. The allocation will result in a 8MB BAR, more than various guest firmwares pre-allocates for PCI Bridges hotplug process. Reserve 4 bytes per VQ by default and add a new parameter "page-per-vq" to be used with split drivers. Signed-off-by: Marcel Apfelbaum <marcel@redhat.com> --- Hi, To be applied on top of: [PATCH v5 1/2] pc: Add 2.8 machine (http://patchwork.ozlabs.org/patch/666812/) Thanks, Marcel hw/virtio/virtio-pci.c | 18 +++++++++++------- hw/virtio/virtio-pci.h | 6 ++++++ include/hw/compat.h | 6 +++++- 3 files changed, 22 insertions(+), 8 deletions(-)