diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-driver-pciback | 13 | ||||
| -rw-r--r-- | drivers/xen/xen-pciback/conf_space.c | 37 | ||||
| -rw-r--r-- | drivers/xen/xen-pciback/conf_space.h | 7 | ||||
| -rw-r--r-- | drivers/xen/xen-pciback/conf_space_capability.c | 89 | ||||
| -rw-r--r-- | drivers/xen/xen-pciback/conf_space_header.c | 19 | ||||
| -rw-r--r-- | drivers/xen/xen-pciback/pci_stub.c | 66 | ||||
| -rw-r--r-- | drivers/xen/xen-pciback/pciback.h | 1 |
7 files changed, 232 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-driver-pciback b/Documentation/ABI/testing/sysfs-driver-pciback index 6a733bfa37e6..73308c2b81b0 100644 --- a/Documentation/ABI/testing/sysfs-driver-pciback +++ b/Documentation/ABI/testing/sysfs-driver-pciback @@ -11,3 +11,16 @@ Description: #echo 00:19.0-E0:2:FF > /sys/bus/pci/drivers/pciback/quirks will allow the guest to read and write to the configuration register 0x0E. + +What: /sys/bus/pci/drivers/pciback/allow_interrupt_control +Date: Jan 2020 +KernelVersion: 5.6 +Contact: xen-devel@lists.xenproject.org +Description: + List of devices which can have interrupt control flag (INTx, + MSI, MSI-X) set by a connected guest. It is meant to be set + only when the guest is a stubdomain hosting device model (qemu) + and the actual device is assigned to a HVM. It is not safe + (similar to permissive attribute) to set for a devices assigned + to a PV guest. The device is automatically removed from this + list when the connected pcifront terminates. diff --git a/drivers/xen/xen-pciback/conf_space.c b/drivers/xen/xen-pciback/conf_space.c index 60111719b01f..b20e43e148ce 100644 --- a/drivers/xen/xen-pciback/conf_space.c +++ b/drivers/xen/xen-pciback/conf_space.c @@ -286,6 +286,43 @@ int xen_pcibk_config_write(struct pci_dev *dev, int offset, int size, u32 value) return xen_pcibios_err_to_errno(err); } +int xen_pcibk_get_interrupt_type(struct pci_dev *dev) +{ + int err; + u16 val; + int ret = 0; + + err = pci_read_config_word(dev, PCI_COMMAND, &val); + if (err) + return err; + if (!(val & PCI_COMMAND_INTX_DISABLE)) + ret |= INTERRUPT_TYPE_INTX; + + /* + * Do not trust dev->msi(x)_enabled here, as enabling could be done + * bypassing the pci_*msi* functions, by the qemu. + */ + if (dev->msi_cap) { + err = pci_read_config_word(dev, + dev->msi_cap + PCI_MSI_FLAGS, + &val); + if (err) + return err; + if (val & PCI_MSI_FLAGS_ENABLE) + ret |= INTERRUPT_TYPE_MSI; + } + if (dev->msix_cap) { + err = pci_read_config_word(dev, + dev->msix_cap + PCI_MSIX_FLAGS, + &val); + if (err) + return err; + if (val & PCI_MSIX_FLAGS_ENABLE) + ret |= INTERRUPT_TYPE_MSIX; + } + return ret; +} + void xen_pcibk_config_free_dyn_fields(struct pci_dev *dev) { struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev); diff --git a/drivers/xen/xen-pciback/conf_space.h b/drivers/xen/xen-pciback/conf_space.h index 22db630717ea..28c45180a12e 100644 --- a/drivers/xen/xen-pciback/conf_space.h +++ b/drivers/xen/xen-pciback/conf_space.h @@ -65,6 +65,11 @@ struct config_field_entry { void *data; }; +#define INTERRUPT_TYPE_NONE (1<<0) +#define INTERRUPT_TYPE_INTX (1<<1) +#define INTERRUPT_TYPE_MSI (1<<2) +#define INTERRUPT_TYPE_MSIX (1<<3) + extern bool xen_pcibk_permissive; #define OFFSET(cfg_entry) ((cfg_entry)->base_offset+(cfg_entry)->field->offset) @@ -126,4 +131,6 @@ int xen_pcibk_config_capability_init(void); int xen_pcibk_config_header_add_fields(struct pci_dev *dev); int xen_pcibk_config_capability_add_fields(struct pci_dev *dev); +int xen_pcibk_get_interrupt_type(struct pci_dev *dev); + #endif /* __XEN_PCIBACK_CONF_SPACE_H__ */ diff --git a/drivers/xen/xen-pciback/conf_space_capability.c b/drivers/xen/xen-pciback/conf_space_capability.c index e5694133ebe5..22f13abbe913 100644 --- a/drivers/xen/xen-pciback/conf_space_capability.c +++ b/drivers/xen/xen-pciback/conf_space_capability.c @@ -189,6 +189,85 @@ static const struct config_field caplist_pm[] = { {} }; +static struct msi_msix_field_config { + u16 enable_bit; /* bit for enabling MSI/MSI-X */ + unsigned int int_type; /* interrupt type for exclusiveness check */ +} msi_field_config = { + .enable_bit = PCI_MSI_FLAGS_ENABLE, + .int_type = INTERRUPT_TYPE_MSI, +}, msix_field_config = { + .enable_bit = PCI_MSIX_FLAGS_ENABLE, + .int_type = INTERRUPT_TYPE_MSIX, +}; + +static void *msi_field_init(struct pci_dev *dev, int offset) +{ + return &msi_field_config; +} + +static void *msix_field_init(struct pci_dev *dev, int offset) +{ + return &msix_field_config; +} + +static int msi_msix_flags_write(struct pci_dev *dev, int offset, u16 new_value, + void *data) +{ + int err; + u16 old_value; + const struct msi_msix_field_config *field_config = data; + const struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev); + + if (xen_pcibk_permissive || dev_data->permissive) + goto write; + + err = pci_read_config_word(dev, offset, &old_value); + if (err) + return err; + + if (new_value == old_value) + return 0; + + if (!dev_data->allow_interrupt_control || + (new_value ^ old_value) & ~field_config->enable_bit) + return PCIBIOS_SET_FAILED; + + if (new_value & field_config->enable_bit) { + /* don't allow enabling together with other interrupt types */ + int int_type = xen_pcibk_get_interrupt_type(dev); + + if (int_type == INTERRUPT_TYPE_NONE || + int_type == field_config->int_type) + goto write; + return PCIBIOS_SET_FAILED; + } + +write: + return pci_write_config_word(dev, offset, new_value); +} + +static const struct config_field caplist_msix[] = { + { + .offset = PCI_MSIX_FLAGS, + .size = 2, + .init = msix_field_init, + .u.w.read = xen_pcibk_read_config_word, + .u.w.write = msi_msix_flags_write, + }, + {} +}; + +static const struct config_field caplist_msi[] = { + { + .offset = PCI_MSI_FLAGS, + .size = 2, + .init = msi_field_init, + .u.w.read = xen_pcibk_read_config_word, + .u.w.write = msi_msix_flags_write, + }, + {} +}; + static struct xen_pcibk_config_capability xen_pcibk_config_capability_pm = { .capability = PCI_CAP_ID_PM, .fields = caplist_pm, @@ -197,11 +276,21 @@ static struct xen_pcibk_config_capability xen_pcibk_config_capability_vpd = { .capability = PCI_CAP_ID_VPD, .fields = caplist_vpd, }; +static struct xen_pcibk_config_capability xen_pcibk_config_capability_msi = { + .capability = PCI_CAP_ID_MSI, + .fields = caplist_msi, +}; +static struct xen_pcibk_config_capability xen_pcibk_config_capability_msix = { + .capability = PCI_CAP_ID_MSIX, + .fields = caplist_msix, +}; int xen_pcibk_config_capability_init(void) { register_capability(&xen_pcibk_config_capability_vpd); register_capability(&xen_pcibk_config_capability_pm); + register_capability(&xen_pcibk_config_capability_msi); + register_capability(&xen_pcibk_config_capability_msix); return 0; } diff --git a/drivers/xen/xen-pciback/conf_space_header.c b/drivers/xen/xen-pciback/conf_space_header.c index 10ae24b5a76e..fb4fccb4aecc 100644 --- a/drivers/xen/xen-pciback/conf_space_header.c +++ b/drivers/xen/xen-pciback/conf_space_header.c @@ -117,6 +117,25 @@ static int command_write(struct pci_dev *dev, int offset, u16 value, void *data) pci_clear_mwi(dev); } + if (dev_data && dev_data->allow_interrupt_control) { + if ((cmd->val ^ value) & PCI_COMMAND_INTX_DISABLE) { + if (value & PCI_COMMAND_INTX_DISABLE) { + pci_intx(dev, 0); + } else { + /* Do not allow enabling INTx together with MSI or MSI-X. */ + switch (xen_pcibk_get_interrupt_type(dev)) { + case INTERRUPT_TYPE_NONE: + pci_intx(dev, 1); + break; + case INTERRUPT_TYPE_INTX: + break; + default: + return PCIBIOS_SET_FAILED; + } + } + } + } + cmd->val = value; if (!xen_pcibk_permissive && (!dev_data || !dev_data->permissive)) diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 097410a7cdb7..7af93d65ed51 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -304,6 +304,8 @@ void pcistub_put_pci_dev(struct pci_dev *dev) xen_pcibk_config_reset_dev(dev); xen_pcibk_config_free_dyn_fields(dev); + dev_data->allow_interrupt_control = 0; + xen_unregister_device_domain_owner(dev); spin_lock_irqsave(&found_psdev->lock, flags); @@ -1431,6 +1433,65 @@ static ssize_t permissive_show(struct device_driver *drv, char *buf) } static DRIVER_ATTR_RW(permissive); +static ssize_t allow_interrupt_control_store(struct device_driver *drv, + const char *buf, size_t count) +{ + int domain, bus, slot, func; + int err; + struct pcistub_device *psdev; + struct xen_pcibk_dev_data *dev_data; + + err = str_to_slot(buf, &domain, &bus, &slot, &func); + if (err) + goto out; + + psdev = pcistub_device_find(domain, bus, slot, func); + if (!psdev) { + err = -ENODEV; + goto out; + } + + dev_data = pci_get_drvdata(psdev->dev); + /* the driver data for a device should never be null at this point */ + if (!dev_data) { + err = -ENXIO; + goto release; + } + dev_data->allow_interrupt_control = 1; +release: + pcistub_device_put(psdev); +out: + if (!err) + err = count; + return err; +} + +static ssize_t allow_interrupt_control_show(struct device_driver *drv, + char *buf) +{ + struct pcistub_device *psdev; + struct xen_pcibk_dev_data *dev_data; + size_t count = 0; + unsigned long flags; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (count >= PAGE_SIZE) + break; + if (!psdev->dev) + continue; + dev_data = pci_get_drvdata(psdev->dev); + if (!dev_data || !dev_data->allow_interrupt_control) + continue; + count += + scnprintf(buf + count, PAGE_SIZE - count, "%s\n", + pci_name(psdev->dev)); + } + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + return count; +} +static DRIVER_ATTR_RW(allow_interrupt_control); + static void pcistub_exit(void) { driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot); @@ -1441,6 +1502,8 @@ static void pcistub_exit(void) driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_permissive); driver_remove_file(&xen_pcibk_pci_driver.driver, + &driver_attr_allow_interrupt_control); + driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_irq_handlers); driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_irq_handler_state); @@ -1530,6 +1593,9 @@ static int __init pcistub_init(void) if (!err) err = driver_create_file(&xen_pcibk_pci_driver.driver, &driver_attr_permissive); + if (!err) + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_allow_interrupt_control); if (!err) err = driver_create_file(&xen_pcibk_pci_driver.driver, diff --git a/drivers/xen/xen-pciback/pciback.h b/drivers/xen/xen-pciback/pciback.h index 263c059bff90..ce1077e32466 100644 --- a/drivers/xen/xen-pciback/pciback.h +++ b/drivers/xen/xen-pciback/pciback.h @@ -45,6 +45,7 @@ struct xen_pcibk_dev_data { struct list_head config_fields; struct pci_saved_state *pci_saved_state; unsigned int permissive:1; + unsigned int allow_interrupt_control:1; unsigned int warned_on_write:1; unsigned int enable_intx:1; unsigned int isr_on:1; /* Whether the IRQ handler is installed. */ |