blob: 62d15f652bb6530f72605eea0cd3b964fd02a3f8 [file] [log] [blame]
/*
* PCIE AER software error injection support.
*
* Debuging 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:
* http://www.kernel.org/pub/linux/utils/pci/aer-inject/
*
* Copyright 2009 Intel Corporation.
* Huang Ying <ying.huang@intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; version 2
* of the License.
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/pci.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include "aerdrv.h"
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;
};
struct aer_error {
struct list_head list;
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, unsigned int bus,
unsigned int devfn, int pos_cap_err)
{
INIT_LIST_HEAD(&err->list);
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(unsigned int bus, unsigned int devfn)
{
struct aer_error *err;
list_for_each_entry(err, &einjected, list) {
if (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)
{
return __find_aer_error(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 = NULL;
spin_lock_irqsave(&inject_lock, flags);
if (list_empty(&pci_bus_ops_list))
bus_ops = NULL;
else {
struct list_head *lh = pci_bus_ops_list.next;
list_del(lh);
bus_ops = list_entry(lh, struct pci_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_COR_SRC:
target = &err->source_id;
break;
}
if (prw1cs)
*prw1cs = rw1cs;
return target;
}
static int pci_read_aer(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 *val)
{
u32 *sim;
struct aer_error *err;
unsigned long flags;
struct pci_ops *ops;
spin_lock_irqsave(&inject_lock, flags);
if (size != sizeof(u32))
goto out;
err = __find_aer_error(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:
ops = __find_pci_bus_ops(bus);
spin_unlock_irqrestore(&inject_lock, flags);
return ops->read(bus, devfn, where, size, val);
}
int pci_write_aer(struct pci_bus *bus, unsigned int devfn, int where, int size,
u32 val)
{
u32 *sim;
struct aer_error *err;
unsigned long flags;
int rw1cs;
struct pci_ops *ops;
spin_lock_irqsave(&inject_lock, flags);
if (size != sizeof(u32))
goto out;
err = __find_aer_error(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:
ops = __find_pci_bus_ops(bus);
spin_unlock_irqrestore(&inject_lock, flags);
return ops->write(bus, devfn, where, size, val);
}
static struct pci_ops pci_ops_aer = {
.read = pci_read_aer,
.write = pci_write_aer,
};
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, &pci_ops_aer);
spin_lock_irqsave(&inject_lock, flags);
if (ops == &pci_ops_aer)
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 struct pci_dev *pcie_find_root_port(struct pci_dev *dev)
{
while (1) {
if (!dev->is_pcie)
break;
if (dev->pcie_type == PCI_EXP_TYPE_ROOT_PORT)
return dev;
if (!dev->bus->self)
break;
dev = dev->bus->self;
}
return NULL;
}
static int find_aer_device_iter(struct device *device, void *data)
{
struct pcie_device **result = data;
struct pcie_device *pcie_dev;
if (device->bus == &pcie_port_bus_type) {
pcie_dev = to_pcie_device(device);
if (pcie_dev->service & PCIE_PORT_SERVICE_AER) {
*result = pcie_dev;
return 1;
}
}
return 0;
}
static int find_aer_device(struct pci_dev *dev, struct pcie_device **result)
{
return device_for_each_child(&dev->dev, result, find_aer_device_iter);
}
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;
unsigned long flags;
unsigned int devfn = PCI_DEVFN(einj->dev, einj->fn);
int pos_cap_err, rp_pos_cap_err;
u32 sever;
int ret = 0;
dev = pci_get_bus_and_slot(einj->bus, devfn);
if (!dev)
return -EINVAL;
rpdev = pcie_find_root_port(dev);
if (!rpdev) {
ret = -EINVAL;
goto out_put;
}
pos_cap_err = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
if (!pos_cap_err) {
ret = -EIO;
goto out_put;
}
pci_read_config_dword(dev, pos_cap_err + PCI_ERR_UNCOR_SEVER, &sever);
rp_pos_cap_err = pci_find_ext_capability(rpdev, PCI_EXT_CAP_ID_ERR);
if (!rp_pos_cap_err) {
ret = -EIO;
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;
}
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->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;
rperr = __find_aer_error_by_dev(rpdev);
if (!rperr) {
rperr = rperr_alloc;
rperr_alloc = NULL;
aer_error_init(rperr, 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);
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;
if (find_aer_device(rpdev, &edev))
aer_irq(-1, edev);
else
ret = -EINVAL;
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 != sizeof(struct aer_error_inj))
return -EINVAL;
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,
};
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, &pci_bus_ops_list, 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");