On Thu, Nov 04, 2010 at 02:18:21PM +0800, Sheng Yang wrote:
> This patch emulated MSI-X per vector mask bit on assigned device.
>
> Signed-off-by: Sheng Yang <sheng@xxxxxxxxxxxxxxx>
> ---
> hw/device-assignment.c | 161 ++++++++++++++++++++++++++++++++++++++++++++++--
> 1 files changed, 155 insertions(+), 6 deletions(-)
>
> diff --git a/hw/device-assignment.c b/hw/device-assignment.c
> index 8a98876..639aa0b 100644
> --- a/hw/device-assignment.c
> +++ b/hw/device-assignment.c
> @@ -62,6 +62,11 @@ static void assigned_dev_load_option_rom(AssignedDevice *dev);
>
> static void assigned_dev_unregister_msix_mmio(AssignedDevice *dev);
>
> +static uint32_t calc_assigned_dev_id(uint16_t seg, uint8_t bus, uint8_t devfn)
> +{
> + return (uint32_t)seg << 16 | (uint32_t)bus << 8 | (uint32_t)devfn;
> +}
> +
> static uint32_t assigned_dev_ioport_rw(AssignedDevRegion *dev_region,
> uint32_t addr, int len, uint32_t *val)
> {
> @@ -264,6 +269,9 @@ static void assigned_dev_iomem_map(PCIDevice *pci_dev, int region_num,
> AssignedDevRegion *region = &r_dev->v_addrs[region_num];
> PCIRegion *real_region = &r_dev->real_device.regions[region_num];
> int ret = 0;
> +#ifdef KVM_CAP_DEVICE_MSIX_MASK
> + struct kvm_assigned_msix_mmio msix_mmio;
> +#endif
>
> DEBUG("e_phys=%08" FMT_PCIBUS " r_virt=%p type=%d len=%08" FMT_PCIBUS " region_num=%d \n",
> e_phys, region->u.r_virtbase, type, e_size, region_num);
> @@ -282,6 +290,16 @@ static void assigned_dev_iomem_map(PCIDevice *pci_dev, int region_num,
>
> cpu_register_physical_memory(e_phys + offset,
> TARGET_PAGE_SIZE, r_dev->mmio_index);
> +#ifdef KVM_CAP_DEVICE_MSIX_MASK
> + memset(&msix_mmio, 0, sizeof(struct kvm_assigned_msix_mmio));
> + msix_mmio.assigned_dev_id = calc_assigned_dev_id(r_dev->h_segnr,
> + r_dev->h_busnr, r_dev->h_devfn);
> + msix_mmio.base_addr = e_phys + offset;
> + /* We required kernel MSI-X support */
> + ret = kvm_assign_reg_msix_mmio(kvm_context, &msix_mmio);
> + if (ret)
> + fprintf(stderr, "fail to register in-kernel msix_mmio!\n");
> +#endif
> }
> }
>
> @@ -824,11 +842,6 @@ static void free_assigned_device(AssignedDevice *dev)
> }
> }
>
> -static uint32_t calc_assigned_dev_id(uint16_t seg, uint8_t bus, uint8_t devfn)
> -{
> - return (uint32_t)seg << 16 | (uint32_t)bus << 8 | (uint32_t)devfn;
> -}
> -
> static void assign_failed_examine(AssignedDevice *dev)
> {
> char name[PATH_MAX], dir[PATH_MAX], driver[PATH_MAX] = {}, *ns;
> @@ -1123,6 +1136,27 @@ static int get_msix_entries_max_nr(AssignedDevice *adev)
> return entries_max_nr;
> }
>
> +#ifdef KVM_CAP_DEVICE_MSIX_MASK
> +static int assigned_dev_msix_entry_masked(AssignedDevice *adev, int entry)
> +{
> + struct kvm_assigned_msix_entry msix_entry;
> + int r;
> +
> + memset(&msix_entry, 0, sizeof msix_entry);
> + msix_entry.assigned_dev_id = calc_assigned_dev_id(adev->h_segnr,
> + adev->h_busnr, (uint8_t)adev->h_devfn);
> + msix_entry.entry = entry;
> + msix_entry.flags = KVM_MSIX_FLAG_QUERY_MASK;
> + r = kvm_assign_get_msix_entry(kvm_context, &msix_entry);
> + if (r) {
> + fprintf(stderr, "assigned_dev_msix_entry_masked: "
> + "Fail to get mask bit of entry %d\n", entry);
> + return 1;
This error handling seems pretty useless. assert?
> + }
> + return (msix_entry.flags & KVM_MSIX_FLAG_MASK);
> +}
> +#endif
> +
> static int get_msix_valid_entries_nr(AssignedDevice *adev,
> uint16_t entries_max_nr)
> {
> @@ -1136,7 +1170,11 @@ static int get_msix_valid_entries_nr(AssignedDevice *adev,
> memcpy(&msg_ctrl, va + i * 16 + 12, 4);
> memcpy(&msg_data, va + i * 16 + 8, 4);
> /* Ignore unused entry even it's unmasked */
> +#ifdef KVM_CAP_DEVICE_MSIX_MASK
> + if (assigned_dev_msix_entry_masked(adev, i))
> +#else
> if (msg_data == 0)
> +#endif
So, we are replacing msg_data == 0 check with masked check?
If yes why not do this for non-KVM_CAP_DEVICE_MSIX_MASK too?
> continue;
> entries_nr ++;
> }
> @@ -1165,6 +1203,8 @@ static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev,
> }
>
> free_dev_irq_entries(adev);
> + memset(pci_dev->msix_entry_used, 0, KVM_MAX_MSIX_PER_DEV *
> + sizeof(*pci_dev->msix_entry_used));
> adev->irq_entries_nr = entries_nr;
> adev->entry = calloc(entries_nr, sizeof(struct kvm_irq_routing_entry));
> if (!adev->entry) {
> @@ -1179,7 +1219,11 @@ static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev,
> break;
> memcpy(&msg_ctrl, va + i * 16 + 12, 4);
> memcpy(&msg_data, va + i * 16 + 8, 4);
> +#ifdef KVM_CAP_DEVICE_MSIX_MASK
> + if (assigned_dev_msix_entry_masked(adev, i))
> +#else
> if (msg_data == 0)
> +#endif
You can't use ifdef to check that kernel supports an ioctl.
You must check this at runtime.
> continue;
>
> memcpy(&msg_addr, va + i * 16, 4);
> @@ -1200,6 +1244,7 @@ static int assigned_dev_update_msix_mmio(PCIDevice *pci_dev,
>
> msix_entry.gsi = adev->entry[entries_nr].gsi;
> msix_entry.entry = i;
> + pci_dev->msix_entry_used[i] = 1;
> r = kvm_assign_set_msix_entry(kvm_context, &msix_entry);
> if (r) {
> fprintf(stderr, "fail to set MSI-X entry! %s\n", strerror(-r));
> @@ -1243,6 +1288,8 @@ static void assigned_dev_update_msix(PCIDevice *pci_dev, int enable_msix)
> perror("assigned_dev_update_msix: deassign irq");
>
> assigned_dev->irq_requested_type = 0;
> + memset(pci_dev->msix_entry_used, 0, KVM_MAX_MSIX_PER_DEV *
> + sizeof(*pci_dev->msix_entry_used));
> }
>
> entries_max_nr = get_msix_entries_max_nr(assigned_dev);
> @@ -1250,10 +1297,16 @@ static void assigned_dev_update_msix(PCIDevice *pci_dev, int enable_msix)
> fprintf(stderr, "assigned_dev_update_msix: MSI-X entries_max_nr == 0");
> return;
> }
> + /*
> + * Guest may try to enable MSI-X before setting MSI-X entry done, so
> + * let's wait until guest unmask the entries.
> + */
Well it can also set up any number of entries, enable msix then
set up more entries. Now what?
> entries_nr = get_msix_valid_entries_nr(assigned_dev, entries_max_nr);
> if (entries_nr == 0) {
> +#ifndef KVM_CAP_DEVICE_MSIX_MASK
> if (enable_msix)
> fprintf(stderr, "MSI-X entry number is zero!\n");
And what happens then?
> +#endif
> return;
> }
> if (enable_msix) {
> @@ -1297,7 +1350,8 @@ static void assigned_device_pci_cap_write_config(PCIDevice *pci_dev, uint32_t ad
> if (address <= ctrl_pos && address + len > ctrl_pos) {
> ctrl_pos--; /* control is word long */
> ctrl_word = (uint16_t *)(pci_dev->config + ctrl_pos);
> - assigned_dev_update_msix(pci_dev, (*ctrl_word & PCI_MSIX_ENABLE));
> + assigned_dev_update_msix(pci_dev,
> + (*ctrl_word & PCI_MSIX_ENABLE) && !(*ctrl_word & PCI_MSIX_MASK));
> }
> pos += PCI_CAPABILITY_CONFIG_MSIX_LENGTH;
> }
> @@ -1395,10 +1449,101 @@ static void msix_mmio_writel(void *opaque,
> AssignedDevice *adev = opaque;
> unsigned int offset = addr & 0xfff;
> void *page = adev->msix_table_page;
> +#ifdef KVM_CAP_DEVICE_MSIX_MASK
> + int pos, ctrl_word, index;
> + struct kvm_irq_routing_entry new_entry = {};
> + int entry_idx, entries_max_nr, r = 0, i;
> + uint32_t msg_ctrl, msg_data, msg_upper_addr, msg_addr;
> +#endif
>
> DEBUG("write to MSI-X entry table mmio offset 0x%lx, val 0x%x\n",
> addr, val);
> memcpy((void *)((char *)page + offset), &val, 4);
> +
> +#ifdef KVM_CAP_DEVICE_MSIX_MASK
> + index = offset / 16;
> +
> + /* Check if mask bit is being accessed */
> + memcpy(&msg_addr, (char *)page + index * 16, 4);
> + memcpy(&msg_upper_addr, (char *)page + index * 16 + 4, 4);
> + memcpy(&msg_data, (char *)page + index * 16 + 8, 4);
> + memcpy(&msg_ctrl, (char *)page + index * 16 + 12, 4);
> + DEBUG("MSI-X entries index %d: "
> + "msg_addr 0x%x, msg_upper_addr 0x%x, msg_data 0x%x, vec_ctl 0x%x\n",
> + index, msg_addr, msg_upper_addr, msg_data, msg_ctrl);
> +
> + if (adev->cap.available & ASSIGNED_DEVICE_CAP_MSI)
> + pos = adev->dev.cap.start + PCI_CAPABILITY_CONFIG_MSI_LENGTH;
> + else
> + pos = adev->dev.cap.start;
> +
> + ctrl_word = *(uint16_t *)(adev->dev.config + pos + 2);
> +
> + if (!((ctrl_word & PCI_MSIX_ENABLE) && !(ctrl_word & PCI_MSIX_MASK)))
> + return;
> +
> + if (!assigned_dev_msix_entry_masked(adev, index)) {
> + if (!adev->dev.msix_entry_used[index]) {
> + DEBUG("Try to modify unenabled MSI-X entry %d's mask. "
> + "Reenable MSI-X.\n",
> + index);
> + assigned_dev_update_msix(&adev->dev, 1);
> + }
> + return;
> + }
> +
> + if (!adev->dev.msix_entry_used[index])
> + return;
> +
> + /*
> + * We're here only because guest want to modify MSI data/addr, and
> + * kernel would filter those writing with mask bit unset.
> + */
> + entries_max_nr = get_msix_entries_max_nr(adev);
> +
> + /*
> + * Find the index of routing entry, it can be different from 'index' if
> + * empty entry existed in between
> + */
> + entry_idx = -1;
> + for (i = 0; i <= index; i++) {
> + if (adev->dev.msix_entry_used[i])
> + entry_idx ++;
> + }
> + if (entry_idx >= entries_max_nr || entry_idx == -1) {
> + fprintf(stderr, "msix_mmio_writel: Entry idx %d exceed limit!\n",
> + entry_idx);
> + return;
> + }
> +
> + if (!assigned_dev_msix_entry_masked(adev, index)) {
> + fprintf(stderr, "msix_mmio_writel: Trying write to unmasked entry!\n");
> + return;
> + }
> +
> + new_entry.gsi = adev->entry[entry_idx].gsi;
> + new_entry.type = KVM_IRQ_ROUTING_MSI;
> + new_entry.flags = 0;
> + new_entry.u.msi.address_lo = msg_addr;
> + new_entry.u.msi.address_hi = msg_upper_addr;
> + new_entry.u.msi.data = msg_data;
> + if (memcmp(&adev->entry[entry_idx].u.msi, &new_entry.u.msi,
> + sizeof new_entry.u.msi)) {
> + r = kvm_update_routing_entry(&adev->entry[entry_idx], &new_entry);
> + if (r) {
> + perror("msix_mmio_writel: kvm_update_routing_entry failed\n");
> + return;
> + }
> + r = kvm_commit_irq_routes();
> + if (r) {
> + perror("msix_mmio_writel: kvm_commit_irq_routes failed\n");
> + return;
> + }
> + }
> + adev->entry[entry_idx].u.msi.address_lo = msg_addr;
> + adev->entry[entry_idx].u.msi.address_hi = msg_upper_addr;
> + adev->entry[entry_idx].u.msi.data = msg_data;
> +#endif
> }
>
> static void msix_mmio_writew(void *opaque,
> @@ -1436,6 +1581,8 @@ static int assigned_dev_register_msix_mmio(AssignedDevice *dev)
> memset(dev->msix_table_page, 0, 0x1000);
> dev->mmio_index = cpu_register_io_memory(
> msix_mmio_read, msix_mmio_write, dev);
> + dev->dev.msix_entry_used = qemu_mallocz(KVM_MAX_MSIX_PER_DEV *
> + sizeof *dev->dev.msix_entry_used);
> return 0;
> }
>
> @@ -1452,6 +1599,8 @@ static void assigned_dev_unregister_msix_mmio(AssignedDevice *dev)
> strerror(errno));
> }
> dev->msix_table_page = NULL;
> + free(dev->dev.msix_entry_used);
> + dev->dev.msix_entry_used = NULL;
> }
>
> static int assigned_initfn(struct PCIDevice *pci_dev)
> --
> 1.7.0.1
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