1 files changed, 551 insertions, 0 deletions

diff --git a/drivers/pci/pcie/aer_inject.c b/drivers/pci/pcie/aer_inject.c
new file mode 100644
index 000000000000..0eb24346cad3
--- /dev/null
+++ b/drivers/pci/pcie/aer_inject.c
@@ -0,0 +1,551 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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>
+ */
+
+#include <linux/module.h>
+#include <linux/init.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_config(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;
+	struct pci_ops *my_ops;
+	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:
+	ops = __find_pci_bus_ops(bus);
+	/*
+	 * pci_lock must already be held, so we can directly
+	 * manipulate bus->ops.  Many config access functions,
+	 * including pci_generic_config_read() require the original
+	 * bus->ops be installed to function, so temporarily put them
+	 * back.
+	 */
+	my_ops = bus->ops;
+	bus->ops = ops;
+	rv = ops->read(bus, devfn, where, size, val);
+	bus->ops = my_ops;
+	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;
+	struct pci_ops *ops;
+	struct pci_ops *my_ops;
+	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:
+	ops = __find_pci_bus_ops(bus);
+	/*
+	 * pci_lock must already be held, so we can directly
+	 * manipulate bus->ops.  Many config access functions,
+	 * including pci_generic_config_write() require the original
+	 * bus->ops be installed to function, so temporarily put them
+	 * back.
+	 */
+	my_ops = bus->ops;
+	bus->ops = ops;
+	rv = ops->write(bus, devfn, where, size, val);
+	bus->ops = my_ops;
+	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 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, 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 (!rpdev) {
+		pci_err(dev, "aer_inject: Root port not found\n");
+		ret = -ENODEV;
+		goto out_put;
+	}
+
+	pos_cap_err = dev->aer_cap;
+	if (!pos_cap_err) {
+		pci_err(dev, "aer_inject: 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, "aer_inject: 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, "aer_inject: 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, "aer_inject: 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;
+
+	if (find_aer_device(rpdev, &edev)) {
+		if (!get_service_data(edev)) {
+			dev_warn(&edev->device,
+				 "aer_inject: AER service is not initialized\n");
+			ret = -EPROTONOSUPPORT;
+			goto out_put;
+		}
+		dev_info(&edev->device,
+			 "aer_inject: Injecting errors %08x/%08x into device %s\n",
+			 einj->cor_status, einj->uncor_status, pci_name(dev));
+		aer_irq(-1, edev);
+	} else {
+		pci_err(rpdev, "aer_inject: 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");