diff options
Diffstat (limited to 'drivers/pci/pcie/aer_inject.c')
| -rw-r--r-- | drivers/pci/pcie/aer_inject.c | 548 |
1 files changed, 548 insertions, 0 deletions
diff --git a/drivers/pci/pcie/aer_inject.c b/drivers/pci/pcie/aer_inject.c new file mode 100644 index 000000000..2dab275d2 --- /dev/null +++ b/drivers/pci/pcie/aer_inject.c @@ -0,0 +1,548 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCIe AER software error injection support. + * + * Debugging PCIe AER code is quite difficult because it is hard to + * trigger various real hardware errors. Software based error + * injection can fake almost all kinds of errors with the help of a + * user space helper tool aer-inject, which can be gotten from: + * https://git.kernel.org/cgit/linux/kernel/git/gong.chen/aer-inject.git/ + * + * Copyright 2009 Intel Corporation. + * Huang Ying <ying.huang@intel.com> + */ + +#define dev_fmt(fmt) "aer_inject: " fmt + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/miscdevice.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/uaccess.h> +#include <linux/stddef.h> +#include <linux/device.h> + +#include "portdrv.h" + +/* Override the existing corrected and uncorrected error masks */ +static bool aer_mask_override; +module_param(aer_mask_override, bool, 0); + +struct aer_error_inj { + u8 bus; + u8 dev; + u8 fn; + u32 uncor_status; + u32 cor_status; + u32 header_log0; + u32 header_log1; + u32 header_log2; + u32 header_log3; + u32 domain; +}; + +struct aer_error { + struct list_head list; + u32 domain; + unsigned int bus; + unsigned int devfn; + int pos_cap_err; + + u32 uncor_status; + u32 cor_status; + u32 header_log0; + u32 header_log1; + u32 header_log2; + u32 header_log3; + u32 root_status; + u32 source_id; +}; + +struct pci_bus_ops { + struct list_head list; + struct pci_bus *bus; + struct pci_ops *ops; +}; + +static LIST_HEAD(einjected); + +static LIST_HEAD(pci_bus_ops_list); + +/* Protect einjected and pci_bus_ops_list */ +static DEFINE_SPINLOCK(inject_lock); + +static void aer_error_init(struct aer_error *err, u32 domain, + unsigned int bus, unsigned int devfn, + int pos_cap_err) +{ + INIT_LIST_HEAD(&err->list); + err->domain = domain; + err->bus = bus; + err->devfn = devfn; + err->pos_cap_err = pos_cap_err; +} + +/* inject_lock must be held before calling */ +static struct aer_error *__find_aer_error(u32 domain, unsigned int bus, + unsigned int devfn) +{ + struct aer_error *err; + + list_for_each_entry(err, &einjected, list) { + if (domain == err->domain && + bus == err->bus && + devfn == err->devfn) + return err; + } + return NULL; +} + +/* inject_lock must be held before calling */ +static struct aer_error *__find_aer_error_by_dev(struct pci_dev *dev) +{ + int domain = pci_domain_nr(dev->bus); + if (domain < 0) + return NULL; + return __find_aer_error(domain, dev->bus->number, dev->devfn); +} + +/* inject_lock must be held before calling */ +static struct pci_ops *__find_pci_bus_ops(struct pci_bus *bus) +{ + struct pci_bus_ops *bus_ops; + + list_for_each_entry(bus_ops, &pci_bus_ops_list, list) { + if (bus_ops->bus == bus) + return bus_ops->ops; + } + return NULL; +} + +static struct pci_bus_ops *pci_bus_ops_pop(void) +{ + unsigned long flags; + struct pci_bus_ops *bus_ops; + + spin_lock_irqsave(&inject_lock, flags); + bus_ops = list_first_entry_or_null(&pci_bus_ops_list, + struct pci_bus_ops, list); + if (bus_ops) + list_del(&bus_ops->list); + spin_unlock_irqrestore(&inject_lock, flags); + return bus_ops; +} + +static u32 *find_pci_config_dword(struct aer_error *err, int where, + int *prw1cs) +{ + int rw1cs = 0; + u32 *target = NULL; + + if (err->pos_cap_err == -1) + return NULL; + + switch (where - err->pos_cap_err) { + case PCI_ERR_UNCOR_STATUS: + target = &err->uncor_status; + rw1cs = 1; + break; + case PCI_ERR_COR_STATUS: + target = &err->cor_status; + rw1cs = 1; + break; + case PCI_ERR_HEADER_LOG: + target = &err->header_log0; + break; + case PCI_ERR_HEADER_LOG+4: + target = &err->header_log1; + break; + case PCI_ERR_HEADER_LOG+8: + target = &err->header_log2; + break; + case PCI_ERR_HEADER_LOG+12: + target = &err->header_log3; + break; + case PCI_ERR_ROOT_STATUS: + target = &err->root_status; + rw1cs = 1; + break; + case PCI_ERR_ROOT_ERR_SRC: + target = &err->source_id; + break; + } + if (prw1cs) + *prw1cs = rw1cs; + return target; +} + +static int aer_inj_read(struct pci_bus *bus, unsigned int devfn, int where, + int size, u32 *val) +{ + struct pci_ops *ops, *my_ops; + int rv; + + ops = __find_pci_bus_ops(bus); + if (!ops) + return -1; + + my_ops = bus->ops; + bus->ops = ops; + rv = ops->read(bus, devfn, where, size, val); + bus->ops = my_ops; + + return rv; +} + +static int aer_inj_write(struct pci_bus *bus, unsigned int devfn, int where, + int size, u32 val) +{ + struct pci_ops *ops, *my_ops; + int rv; + + ops = __find_pci_bus_ops(bus); + if (!ops) + return -1; + + my_ops = bus->ops; + bus->ops = ops; + rv = ops->write(bus, devfn, where, size, val); + bus->ops = my_ops; + + return rv; +} + +static int aer_inj_read_config(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 *val) +{ + u32 *sim; + struct aer_error *err; + unsigned long flags; + int domain; + int rv; + + spin_lock_irqsave(&inject_lock, flags); + if (size != sizeof(u32)) + goto out; + domain = pci_domain_nr(bus); + if (domain < 0) + goto out; + err = __find_aer_error(domain, bus->number, devfn); + if (!err) + goto out; + + sim = find_pci_config_dword(err, where, NULL); + if (sim) { + *val = *sim; + spin_unlock_irqrestore(&inject_lock, flags); + return 0; + } +out: + rv = aer_inj_read(bus, devfn, where, size, val); + spin_unlock_irqrestore(&inject_lock, flags); + return rv; +} + +static int aer_inj_write_config(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 val) +{ + u32 *sim; + struct aer_error *err; + unsigned long flags; + int rw1cs; + int domain; + int rv; + + spin_lock_irqsave(&inject_lock, flags); + if (size != sizeof(u32)) + goto out; + domain = pci_domain_nr(bus); + if (domain < 0) + goto out; + err = __find_aer_error(domain, bus->number, devfn); + if (!err) + goto out; + + sim = find_pci_config_dword(err, where, &rw1cs); + if (sim) { + if (rw1cs) + *sim ^= val; + else + *sim = val; + spin_unlock_irqrestore(&inject_lock, flags); + return 0; + } +out: + rv = aer_inj_write(bus, devfn, where, size, val); + spin_unlock_irqrestore(&inject_lock, flags); + return rv; +} + +static struct pci_ops aer_inj_pci_ops = { + .read = aer_inj_read_config, + .write = aer_inj_write_config, +}; + +static void pci_bus_ops_init(struct pci_bus_ops *bus_ops, + struct pci_bus *bus, + struct pci_ops *ops) +{ + INIT_LIST_HEAD(&bus_ops->list); + bus_ops->bus = bus; + bus_ops->ops = ops; +} + +static int pci_bus_set_aer_ops(struct pci_bus *bus) +{ + struct pci_ops *ops; + struct pci_bus_ops *bus_ops; + unsigned long flags; + + bus_ops = kmalloc(sizeof(*bus_ops), GFP_KERNEL); + if (!bus_ops) + return -ENOMEM; + ops = pci_bus_set_ops(bus, &aer_inj_pci_ops); + spin_lock_irqsave(&inject_lock, flags); + if (ops == &aer_inj_pci_ops) + goto out; + pci_bus_ops_init(bus_ops, bus, ops); + list_add(&bus_ops->list, &pci_bus_ops_list); + bus_ops = NULL; +out: + spin_unlock_irqrestore(&inject_lock, flags); + kfree(bus_ops); + return 0; +} + +static int aer_inject(struct aer_error_inj *einj) +{ + struct aer_error *err, *rperr; + struct aer_error *err_alloc = NULL, *rperr_alloc = NULL; + struct pci_dev *dev, *rpdev; + struct pcie_device *edev; + struct device *device; + unsigned long flags; + unsigned int devfn = PCI_DEVFN(einj->dev, einj->fn); + int pos_cap_err, rp_pos_cap_err; + u32 sever, cor_mask, uncor_mask, cor_mask_orig = 0, uncor_mask_orig = 0; + int ret = 0; + + dev = pci_get_domain_bus_and_slot(einj->domain, einj->bus, devfn); + if (!dev) + return -ENODEV; + rpdev = pcie_find_root_port(dev); + /* If Root Port not found, try to find an RCEC */ + if (!rpdev) + rpdev = dev->rcec; + if (!rpdev) { + pci_err(dev, "Neither Root Port nor RCEC found\n"); + ret = -ENODEV; + goto out_put; + } + + pos_cap_err = dev->aer_cap; + if (!pos_cap_err) { + pci_err(dev, "Device doesn't support AER\n"); + ret = -EPROTONOSUPPORT; + goto out_put; + } + pci_read_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_SEVER, &sever); + pci_read_config_dword(dev, pos_cap_err + PCI_ERR_COR_MASK, &cor_mask); + pci_read_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_MASK, + &uncor_mask); + + rp_pos_cap_err = rpdev->aer_cap; + if (!rp_pos_cap_err) { + pci_err(rpdev, "Root port doesn't support AER\n"); + ret = -EPROTONOSUPPORT; + goto out_put; + } + + err_alloc = kzalloc(sizeof(struct aer_error), GFP_KERNEL); + if (!err_alloc) { + ret = -ENOMEM; + goto out_put; + } + rperr_alloc = kzalloc(sizeof(struct aer_error), GFP_KERNEL); + if (!rperr_alloc) { + ret = -ENOMEM; + goto out_put; + } + + if (aer_mask_override) { + cor_mask_orig = cor_mask; + cor_mask &= !(einj->cor_status); + pci_write_config_dword(dev, pos_cap_err + PCI_ERR_COR_MASK, + cor_mask); + + uncor_mask_orig = uncor_mask; + uncor_mask &= !(einj->uncor_status); + pci_write_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_MASK, + uncor_mask); + } + + spin_lock_irqsave(&inject_lock, flags); + + err = __find_aer_error_by_dev(dev); + if (!err) { + err = err_alloc; + err_alloc = NULL; + aer_error_init(err, einj->domain, einj->bus, devfn, + pos_cap_err); + list_add(&err->list, &einjected); + } + err->uncor_status |= einj->uncor_status; + err->cor_status |= einj->cor_status; + err->header_log0 = einj->header_log0; + err->header_log1 = einj->header_log1; + err->header_log2 = einj->header_log2; + err->header_log3 = einj->header_log3; + + if (!aer_mask_override && einj->cor_status && + !(einj->cor_status & ~cor_mask)) { + ret = -EINVAL; + pci_warn(dev, "The correctable error(s) is masked by device\n"); + spin_unlock_irqrestore(&inject_lock, flags); + goto out_put; + } + if (!aer_mask_override && einj->uncor_status && + !(einj->uncor_status & ~uncor_mask)) { + ret = -EINVAL; + pci_warn(dev, "The uncorrectable error(s) is masked by device\n"); + spin_unlock_irqrestore(&inject_lock, flags); + goto out_put; + } + + rperr = __find_aer_error_by_dev(rpdev); + if (!rperr) { + rperr = rperr_alloc; + rperr_alloc = NULL; + aer_error_init(rperr, pci_domain_nr(rpdev->bus), + rpdev->bus->number, rpdev->devfn, + rp_pos_cap_err); + list_add(&rperr->list, &einjected); + } + if (einj->cor_status) { + if (rperr->root_status & PCI_ERR_ROOT_COR_RCV) + rperr->root_status |= PCI_ERR_ROOT_MULTI_COR_RCV; + else + rperr->root_status |= PCI_ERR_ROOT_COR_RCV; + rperr->source_id &= 0xffff0000; + rperr->source_id |= (einj->bus << 8) | devfn; + } + if (einj->uncor_status) { + if (rperr->root_status & PCI_ERR_ROOT_UNCOR_RCV) + rperr->root_status |= PCI_ERR_ROOT_MULTI_UNCOR_RCV; + if (sever & einj->uncor_status) { + rperr->root_status |= PCI_ERR_ROOT_FATAL_RCV; + if (!(rperr->root_status & PCI_ERR_ROOT_UNCOR_RCV)) + rperr->root_status |= PCI_ERR_ROOT_FIRST_FATAL; + } else + rperr->root_status |= PCI_ERR_ROOT_NONFATAL_RCV; + rperr->root_status |= PCI_ERR_ROOT_UNCOR_RCV; + rperr->source_id &= 0x0000ffff; + rperr->source_id |= ((einj->bus << 8) | devfn) << 16; + } + spin_unlock_irqrestore(&inject_lock, flags); + + if (aer_mask_override) { + pci_write_config_dword(dev, pos_cap_err + PCI_ERR_COR_MASK, + cor_mask_orig); + pci_write_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_MASK, + uncor_mask_orig); + } + + ret = pci_bus_set_aer_ops(dev->bus); + if (ret) + goto out_put; + ret = pci_bus_set_aer_ops(rpdev->bus); + if (ret) + goto out_put; + + device = pcie_port_find_device(rpdev, PCIE_PORT_SERVICE_AER); + if (device) { + edev = to_pcie_device(device); + if (!get_service_data(edev)) { + pci_warn(edev->port, "AER service is not initialized\n"); + ret = -EPROTONOSUPPORT; + goto out_put; + } + pci_info(edev->port, "Injecting errors %08x/%08x into device %s\n", + einj->cor_status, einj->uncor_status, pci_name(dev)); + ret = irq_inject_interrupt(edev->irq); + } else { + pci_err(rpdev, "AER device not found\n"); + ret = -ENODEV; + } +out_put: + kfree(err_alloc); + kfree(rperr_alloc); + pci_dev_put(dev); + return ret; +} + +static ssize_t aer_inject_write(struct file *filp, const char __user *ubuf, + size_t usize, loff_t *off) +{ + struct aer_error_inj einj; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (usize < offsetof(struct aer_error_inj, domain) || + usize > sizeof(einj)) + return -EINVAL; + + memset(&einj, 0, sizeof(einj)); + if (copy_from_user(&einj, ubuf, usize)) + return -EFAULT; + + ret = aer_inject(&einj); + return ret ? ret : usize; +} + +static const struct file_operations aer_inject_fops = { + .write = aer_inject_write, + .owner = THIS_MODULE, + .llseek = noop_llseek, +}; + +static struct miscdevice aer_inject_device = { + .minor = MISC_DYNAMIC_MINOR, + .name = "aer_inject", + .fops = &aer_inject_fops, +}; + +static int __init aer_inject_init(void) +{ + return misc_register(&aer_inject_device); +} + +static void __exit aer_inject_exit(void) +{ + struct aer_error *err, *err_next; + unsigned long flags; + struct pci_bus_ops *bus_ops; + + misc_deregister(&aer_inject_device); + + while ((bus_ops = pci_bus_ops_pop())) { + pci_bus_set_ops(bus_ops->bus, bus_ops->ops); + kfree(bus_ops); + } + + spin_lock_irqsave(&inject_lock, flags); + list_for_each_entry_safe(err, err_next, &einjected, list) { + list_del(&err->list); + kfree(err); + } + spin_unlock_irqrestore(&inject_lock, flags); +} + +module_init(aer_inject_init); +module_exit(aer_inject_exit); + +MODULE_DESCRIPTION("PCIe AER software error injector"); +MODULE_LICENSE("GPL"); |