diff options
Diffstat (limited to 'drivers/thunderbolt/domain.c')
| -rw-r--r-- | drivers/thunderbolt/domain.c | 859 |
1 files changed, 859 insertions, 0 deletions
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c new file mode 100644 index 000000000..f0de94f7a --- /dev/null +++ b/drivers/thunderbolt/domain.c @@ -0,0 +1,859 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Thunderbolt bus support + * + * Copyright (C) 2017, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + */ + +#include <linux/device.h> +#include <linux/dmar.h> +#include <linux/idr.h> +#include <linux/iommu.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <crypto/hash.h> + +#include "tb.h" + +static DEFINE_IDA(tb_domain_ida); + +static bool match_service_id(const struct tb_service_id *id, + const struct tb_service *svc) +{ + if (id->match_flags & TBSVC_MATCH_PROTOCOL_KEY) { + if (strcmp(id->protocol_key, svc->key)) + return false; + } + + if (id->match_flags & TBSVC_MATCH_PROTOCOL_ID) { + if (id->protocol_id != svc->prtcid) + return false; + } + + if (id->match_flags & TBSVC_MATCH_PROTOCOL_VERSION) { + if (id->protocol_version != svc->prtcvers) + return false; + } + + if (id->match_flags & TBSVC_MATCH_PROTOCOL_VERSION) { + if (id->protocol_revision != svc->prtcrevs) + return false; + } + + return true; +} + +static const struct tb_service_id *__tb_service_match(struct device *dev, + struct device_driver *drv) +{ + struct tb_service_driver *driver; + const struct tb_service_id *ids; + struct tb_service *svc; + + svc = tb_to_service(dev); + if (!svc) + return NULL; + + driver = container_of(drv, struct tb_service_driver, driver); + if (!driver->id_table) + return NULL; + + for (ids = driver->id_table; ids->match_flags != 0; ids++) { + if (match_service_id(ids, svc)) + return ids; + } + + return NULL; +} + +static int tb_service_match(struct device *dev, struct device_driver *drv) +{ + return !!__tb_service_match(dev, drv); +} + +static int tb_service_probe(struct device *dev) +{ + struct tb_service *svc = tb_to_service(dev); + struct tb_service_driver *driver; + const struct tb_service_id *id; + + driver = container_of(dev->driver, struct tb_service_driver, driver); + id = __tb_service_match(dev, &driver->driver); + + return driver->probe(svc, id); +} + +static int tb_service_remove(struct device *dev) +{ + struct tb_service *svc = tb_to_service(dev); + struct tb_service_driver *driver; + + driver = container_of(dev->driver, struct tb_service_driver, driver); + if (driver->remove) + driver->remove(svc); + + return 0; +} + +static void tb_service_shutdown(struct device *dev) +{ + struct tb_service_driver *driver; + struct tb_service *svc; + + svc = tb_to_service(dev); + if (!svc || !dev->driver) + return; + + driver = container_of(dev->driver, struct tb_service_driver, driver); + if (driver->shutdown) + driver->shutdown(svc); +} + +static const char * const tb_security_names[] = { + [TB_SECURITY_NONE] = "none", + [TB_SECURITY_USER] = "user", + [TB_SECURITY_SECURE] = "secure", + [TB_SECURITY_DPONLY] = "dponly", + [TB_SECURITY_USBONLY] = "usbonly", +}; + +static ssize_t boot_acl_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb *tb = container_of(dev, struct tb, dev); + uuid_t *uuids; + ssize_t ret; + int i; + + uuids = kcalloc(tb->nboot_acl, sizeof(uuid_t), GFP_KERNEL); + if (!uuids) + return -ENOMEM; + + pm_runtime_get_sync(&tb->dev); + + if (mutex_lock_interruptible(&tb->lock)) { + ret = -ERESTARTSYS; + goto out; + } + ret = tb->cm_ops->get_boot_acl(tb, uuids, tb->nboot_acl); + if (ret) { + mutex_unlock(&tb->lock); + goto out; + } + mutex_unlock(&tb->lock); + + for (ret = 0, i = 0; i < tb->nboot_acl; i++) { + if (!uuid_is_null(&uuids[i])) + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%pUb", + &uuids[i]); + + ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s", + i < tb->nboot_acl - 1 ? "," : "\n"); + } + +out: + pm_runtime_mark_last_busy(&tb->dev); + pm_runtime_put_autosuspend(&tb->dev); + kfree(uuids); + + return ret; +} + +static ssize_t boot_acl_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct tb *tb = container_of(dev, struct tb, dev); + char *str, *s, *uuid_str; + ssize_t ret = 0; + uuid_t *acl; + int i = 0; + + /* + * Make sure the value is not bigger than tb->nboot_acl * UUID + * length + commas and optional "\n". Also the smallest allowable + * string is tb->nboot_acl * ",". + */ + if (count > (UUID_STRING_LEN + 1) * tb->nboot_acl + 1) + return -EINVAL; + if (count < tb->nboot_acl - 1) + return -EINVAL; + + str = kstrdup(buf, GFP_KERNEL); + if (!str) + return -ENOMEM; + + acl = kcalloc(tb->nboot_acl, sizeof(uuid_t), GFP_KERNEL); + if (!acl) { + ret = -ENOMEM; + goto err_free_str; + } + + uuid_str = strim(str); + while ((s = strsep(&uuid_str, ",")) != NULL && i < tb->nboot_acl) { + size_t len = strlen(s); + + if (len) { + if (len != UUID_STRING_LEN) { + ret = -EINVAL; + goto err_free_acl; + } + ret = uuid_parse(s, &acl[i]); + if (ret) + goto err_free_acl; + } + + i++; + } + + if (s || i < tb->nboot_acl) { + ret = -EINVAL; + goto err_free_acl; + } + + pm_runtime_get_sync(&tb->dev); + + if (mutex_lock_interruptible(&tb->lock)) { + ret = -ERESTARTSYS; + goto err_rpm_put; + } + ret = tb->cm_ops->set_boot_acl(tb, acl, tb->nboot_acl); + if (!ret) { + /* Notify userspace about the change */ + kobject_uevent(&tb->dev.kobj, KOBJ_CHANGE); + } + mutex_unlock(&tb->lock); + +err_rpm_put: + pm_runtime_mark_last_busy(&tb->dev); + pm_runtime_put_autosuspend(&tb->dev); +err_free_acl: + kfree(acl); +err_free_str: + kfree(str); + + return ret ?: count; +} +static DEVICE_ATTR_RW(boot_acl); + +static ssize_t iommu_dma_protection_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + /* + * Kernel DMA protection is a feature where Thunderbolt security is + * handled natively using IOMMU. It is enabled when IOMMU is + * enabled and ACPI DMAR table has DMAR_PLATFORM_OPT_IN set. + */ + return sprintf(buf, "%d\n", + iommu_present(&pci_bus_type) && dmar_platform_optin()); +} +static DEVICE_ATTR_RO(iommu_dma_protection); + +static ssize_t security_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb *tb = container_of(dev, struct tb, dev); + const char *name = "unknown"; + + if (tb->security_level < ARRAY_SIZE(tb_security_names)) + name = tb_security_names[tb->security_level]; + + return sprintf(buf, "%s\n", name); +} +static DEVICE_ATTR_RO(security); + +static struct attribute *domain_attrs[] = { + &dev_attr_boot_acl.attr, + &dev_attr_iommu_dma_protection.attr, + &dev_attr_security.attr, + NULL, +}; + +static umode_t domain_attr_is_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct tb *tb = container_of(dev, struct tb, dev); + + if (attr == &dev_attr_boot_acl.attr) { + if (tb->nboot_acl && + tb->cm_ops->get_boot_acl && + tb->cm_ops->set_boot_acl) + return attr->mode; + return 0; + } + + return attr->mode; +} + +static struct attribute_group domain_attr_group = { + .is_visible = domain_attr_is_visible, + .attrs = domain_attrs, +}; + +static const struct attribute_group *domain_attr_groups[] = { + &domain_attr_group, + NULL, +}; + +struct bus_type tb_bus_type = { + .name = "thunderbolt", + .match = tb_service_match, + .probe = tb_service_probe, + .remove = tb_service_remove, + .shutdown = tb_service_shutdown, +}; + +static void tb_domain_release(struct device *dev) +{ + struct tb *tb = container_of(dev, struct tb, dev); + + tb_ctl_free(tb->ctl); + destroy_workqueue(tb->wq); + ida_simple_remove(&tb_domain_ida, tb->index); + mutex_destroy(&tb->lock); + kfree(tb); +} + +struct device_type tb_domain_type = { + .name = "thunderbolt_domain", + .release = tb_domain_release, +}; + +/** + * tb_domain_alloc() - Allocate a domain + * @nhi: Pointer to the host controller + * @privsize: Size of the connection manager private data + * + * Allocates and initializes a new Thunderbolt domain. Connection + * managers are expected to call this and then fill in @cm_ops + * accordingly. + * + * Call tb_domain_put() to release the domain before it has been added + * to the system. + * + * Return: allocated domain structure on %NULL in case of error + */ +struct tb *tb_domain_alloc(struct tb_nhi *nhi, size_t privsize) +{ + struct tb *tb; + + /* + * Make sure the structure sizes map with that the hardware + * expects because bit-fields are being used. + */ + BUILD_BUG_ON(sizeof(struct tb_regs_switch_header) != 5 * 4); + BUILD_BUG_ON(sizeof(struct tb_regs_port_header) != 8 * 4); + BUILD_BUG_ON(sizeof(struct tb_regs_hop) != 2 * 4); + + tb = kzalloc(sizeof(*tb) + privsize, GFP_KERNEL); + if (!tb) + return NULL; + + tb->nhi = nhi; + mutex_init(&tb->lock); + + tb->index = ida_simple_get(&tb_domain_ida, 0, 0, GFP_KERNEL); + if (tb->index < 0) + goto err_free; + + tb->wq = alloc_ordered_workqueue("thunderbolt%d", 0, tb->index); + if (!tb->wq) + goto err_remove_ida; + + tb->dev.parent = &nhi->pdev->dev; + tb->dev.bus = &tb_bus_type; + tb->dev.type = &tb_domain_type; + tb->dev.groups = domain_attr_groups; + dev_set_name(&tb->dev, "domain%d", tb->index); + device_initialize(&tb->dev); + + return tb; + +err_remove_ida: + ida_simple_remove(&tb_domain_ida, tb->index); +err_free: + kfree(tb); + + return NULL; +} + +static bool tb_domain_event_cb(void *data, enum tb_cfg_pkg_type type, + const void *buf, size_t size) +{ + struct tb *tb = data; + + if (!tb->cm_ops->handle_event) { + tb_warn(tb, "domain does not have event handler\n"); + return true; + } + + switch (type) { + case TB_CFG_PKG_XDOMAIN_REQ: + case TB_CFG_PKG_XDOMAIN_RESP: + return tb_xdomain_handle_request(tb, type, buf, size); + + default: + tb->cm_ops->handle_event(tb, type, buf, size); + } + + return true; +} + +/** + * tb_domain_add() - Add domain to the system + * @tb: Domain to add + * + * Starts the domain and adds it to the system. Hotplugging devices will + * work after this has been returned successfully. In order to remove + * and release the domain after this function has been called, call + * tb_domain_remove(). + * + * Return: %0 in case of success and negative errno in case of error + */ +int tb_domain_add(struct tb *tb) +{ + int ret; + + if (WARN_ON(!tb->cm_ops)) + return -EINVAL; + + mutex_lock(&tb->lock); + + tb->ctl = tb_ctl_alloc(tb->nhi, tb_domain_event_cb, tb); + if (!tb->ctl) { + ret = -ENOMEM; + goto err_unlock; + } + + /* + * tb_schedule_hotplug_handler may be called as soon as the config + * channel is started. Thats why we have to hold the lock here. + */ + tb_ctl_start(tb->ctl); + + if (tb->cm_ops->driver_ready) { + ret = tb->cm_ops->driver_ready(tb); + if (ret) + goto err_ctl_stop; + } + + ret = device_add(&tb->dev); + if (ret) + goto err_ctl_stop; + + /* Start the domain */ + if (tb->cm_ops->start) { + ret = tb->cm_ops->start(tb); + if (ret) + goto err_domain_del; + } + + /* This starts event processing */ + mutex_unlock(&tb->lock); + + device_init_wakeup(&tb->dev, true); + + pm_runtime_no_callbacks(&tb->dev); + pm_runtime_set_active(&tb->dev); + pm_runtime_enable(&tb->dev); + pm_runtime_set_autosuspend_delay(&tb->dev, TB_AUTOSUSPEND_DELAY); + pm_runtime_mark_last_busy(&tb->dev); + pm_runtime_use_autosuspend(&tb->dev); + + return 0; + +err_domain_del: + device_del(&tb->dev); +err_ctl_stop: + tb_ctl_stop(tb->ctl); +err_unlock: + mutex_unlock(&tb->lock); + + return ret; +} + +/** + * tb_domain_remove() - Removes and releases a domain + * @tb: Domain to remove + * + * Stops the domain, removes it from the system and releases all + * resources once the last reference has been released. + */ +void tb_domain_remove(struct tb *tb) +{ + mutex_lock(&tb->lock); + if (tb->cm_ops->stop) + tb->cm_ops->stop(tb); + /* Stop the domain control traffic */ + tb_ctl_stop(tb->ctl); + mutex_unlock(&tb->lock); + + flush_workqueue(tb->wq); + device_unregister(&tb->dev); +} + +/** + * tb_domain_suspend_noirq() - Suspend a domain + * @tb: Domain to suspend + * + * Suspends all devices in the domain and stops the control channel. + */ +int tb_domain_suspend_noirq(struct tb *tb) +{ + int ret = 0; + + /* + * The control channel interrupt is left enabled during suspend + * and taking the lock here prevents any events happening before + * we actually have stopped the domain and the control channel. + */ + mutex_lock(&tb->lock); + if (tb->cm_ops->suspend_noirq) + ret = tb->cm_ops->suspend_noirq(tb); + if (!ret) + tb_ctl_stop(tb->ctl); + mutex_unlock(&tb->lock); + + return ret; +} + +/** + * tb_domain_resume_noirq() - Resume a domain + * @tb: Domain to resume + * + * Re-starts the control channel, and resumes all devices connected to + * the domain. + */ +int tb_domain_resume_noirq(struct tb *tb) +{ + int ret = 0; + + mutex_lock(&tb->lock); + tb_ctl_start(tb->ctl); + if (tb->cm_ops->resume_noirq) + ret = tb->cm_ops->resume_noirq(tb); + mutex_unlock(&tb->lock); + + return ret; +} + +int tb_domain_suspend(struct tb *tb) +{ + return tb->cm_ops->suspend ? tb->cm_ops->suspend(tb) : 0; +} + +int tb_domain_freeze_noirq(struct tb *tb) +{ + int ret = 0; + + mutex_lock(&tb->lock); + if (tb->cm_ops->freeze_noirq) + ret = tb->cm_ops->freeze_noirq(tb); + if (!ret) + tb_ctl_stop(tb->ctl); + mutex_unlock(&tb->lock); + + return ret; +} + +int tb_domain_thaw_noirq(struct tb *tb) +{ + int ret = 0; + + mutex_lock(&tb->lock); + tb_ctl_start(tb->ctl); + if (tb->cm_ops->thaw_noirq) + ret = tb->cm_ops->thaw_noirq(tb); + mutex_unlock(&tb->lock); + + return ret; +} + +void tb_domain_complete(struct tb *tb) +{ + if (tb->cm_ops->complete) + tb->cm_ops->complete(tb); +} + +int tb_domain_runtime_suspend(struct tb *tb) +{ + if (tb->cm_ops->runtime_suspend) { + int ret = tb->cm_ops->runtime_suspend(tb); + if (ret) + return ret; + } + tb_ctl_stop(tb->ctl); + return 0; +} + +int tb_domain_runtime_resume(struct tb *tb) +{ + tb_ctl_start(tb->ctl); + if (tb->cm_ops->runtime_resume) { + int ret = tb->cm_ops->runtime_resume(tb); + if (ret) + return ret; + } + return 0; +} + +/** + * tb_domain_approve_switch() - Approve switch + * @tb: Domain the switch belongs to + * @sw: Switch to approve + * + * This will approve switch by connection manager specific means. In + * case of success the connection manager will create tunnels for all + * supported protocols. + */ +int tb_domain_approve_switch(struct tb *tb, struct tb_switch *sw) +{ + struct tb_switch *parent_sw; + + if (!tb->cm_ops->approve_switch) + return -EPERM; + + /* The parent switch must be authorized before this one */ + parent_sw = tb_to_switch(sw->dev.parent); + if (!parent_sw || !parent_sw->authorized) + return -EINVAL; + + return tb->cm_ops->approve_switch(tb, sw); +} + +/** + * tb_domain_approve_switch_key() - Approve switch and add key + * @tb: Domain the switch belongs to + * @sw: Switch to approve + * + * For switches that support secure connect, this function first adds + * key to the switch NVM using connection manager specific means. If + * adding the key is successful, the switch is approved and connected. + * + * Return: %0 on success and negative errno in case of failure. + */ +int tb_domain_approve_switch_key(struct tb *tb, struct tb_switch *sw) +{ + struct tb_switch *parent_sw; + int ret; + + if (!tb->cm_ops->approve_switch || !tb->cm_ops->add_switch_key) + return -EPERM; + + /* The parent switch must be authorized before this one */ + parent_sw = tb_to_switch(sw->dev.parent); + if (!parent_sw || !parent_sw->authorized) + return -EINVAL; + + ret = tb->cm_ops->add_switch_key(tb, sw); + if (ret) + return ret; + + return tb->cm_ops->approve_switch(tb, sw); +} + +/** + * tb_domain_challenge_switch_key() - Challenge and approve switch + * @tb: Domain the switch belongs to + * @sw: Switch to approve + * + * For switches that support secure connect, this function generates + * random challenge and sends it to the switch. The switch responds to + * this and if the response matches our random challenge, the switch is + * approved and connected. + * + * Return: %0 on success and negative errno in case of failure. + */ +int tb_domain_challenge_switch_key(struct tb *tb, struct tb_switch *sw) +{ + u8 challenge[TB_SWITCH_KEY_SIZE]; + u8 response[TB_SWITCH_KEY_SIZE]; + u8 hmac[TB_SWITCH_KEY_SIZE]; + struct tb_switch *parent_sw; + struct crypto_shash *tfm; + struct shash_desc *shash; + int ret; + + if (!tb->cm_ops->approve_switch || !tb->cm_ops->challenge_switch_key) + return -EPERM; + + /* The parent switch must be authorized before this one */ + parent_sw = tb_to_switch(sw->dev.parent); + if (!parent_sw || !parent_sw->authorized) + return -EINVAL; + + get_random_bytes(challenge, sizeof(challenge)); + ret = tb->cm_ops->challenge_switch_key(tb, sw, challenge, response); + if (ret) + return ret; + + tfm = crypto_alloc_shash("hmac(sha256)", 0, 0); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + ret = crypto_shash_setkey(tfm, sw->key, TB_SWITCH_KEY_SIZE); + if (ret) + goto err_free_tfm; + + shash = kzalloc(sizeof(*shash) + crypto_shash_descsize(tfm), + GFP_KERNEL); + if (!shash) { + ret = -ENOMEM; + goto err_free_tfm; + } + + shash->tfm = tfm; + + memset(hmac, 0, sizeof(hmac)); + ret = crypto_shash_digest(shash, challenge, sizeof(hmac), hmac); + if (ret) + goto err_free_shash; + + /* The returned HMAC must match the one we calculated */ + if (memcmp(response, hmac, sizeof(hmac))) { + ret = -EKEYREJECTED; + goto err_free_shash; + } + + crypto_free_shash(tfm); + kfree(shash); + + return tb->cm_ops->approve_switch(tb, sw); + +err_free_shash: + kfree(shash); +err_free_tfm: + crypto_free_shash(tfm); + + return ret; +} + +/** + * tb_domain_disconnect_pcie_paths() - Disconnect all PCIe paths + * @tb: Domain whose PCIe paths to disconnect + * + * This needs to be called in preparation for NVM upgrade of the host + * controller. Makes sure all PCIe paths are disconnected. + * + * Return %0 on success and negative errno in case of error. + */ +int tb_domain_disconnect_pcie_paths(struct tb *tb) +{ + if (!tb->cm_ops->disconnect_pcie_paths) + return -EPERM; + + return tb->cm_ops->disconnect_pcie_paths(tb); +} + +/** + * tb_domain_approve_xdomain_paths() - Enable DMA paths for XDomain + * @tb: Domain enabling the DMA paths + * @xd: XDomain DMA paths are created to + * + * Calls connection manager specific method to enable DMA paths to the + * XDomain in question. + * + * Return: 0% in case of success and negative errno otherwise. In + * particular returns %-ENOTSUPP if the connection manager + * implementation does not support XDomains. + */ +int tb_domain_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd) +{ + if (!tb->cm_ops->approve_xdomain_paths) + return -ENOTSUPP; + + return tb->cm_ops->approve_xdomain_paths(tb, xd); +} + +/** + * tb_domain_disconnect_xdomain_paths() - Disable DMA paths for XDomain + * @tb: Domain disabling the DMA paths + * @xd: XDomain whose DMA paths are disconnected + * + * Calls connection manager specific method to disconnect DMA paths to + * the XDomain in question. + * + * Return: 0% in case of success and negative errno otherwise. In + * particular returns %-ENOTSUPP if the connection manager + * implementation does not support XDomains. + */ +int tb_domain_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd) +{ + if (!tb->cm_ops->disconnect_xdomain_paths) + return -ENOTSUPP; + + return tb->cm_ops->disconnect_xdomain_paths(tb, xd); +} + +static int disconnect_xdomain(struct device *dev, void *data) +{ + struct tb_xdomain *xd; + struct tb *tb = data; + int ret = 0; + + xd = tb_to_xdomain(dev); + if (xd && xd->tb == tb) + ret = tb_xdomain_disable_paths(xd); + + return ret; +} + +/** + * tb_domain_disconnect_all_paths() - Disconnect all paths for the domain + * @tb: Domain whose paths are disconnected + * + * This function can be used to disconnect all paths (PCIe, XDomain) for + * example in preparation for host NVM firmware upgrade. After this is + * called the paths cannot be established without resetting the switch. + * + * Return: %0 in case of success and negative errno otherwise. + */ +int tb_domain_disconnect_all_paths(struct tb *tb) +{ + int ret; + + ret = tb_domain_disconnect_pcie_paths(tb); + if (ret) + return ret; + + return bus_for_each_dev(&tb_bus_type, NULL, tb, disconnect_xdomain); +} + +int tb_domain_init(void) +{ + int ret; + + tb_test_init(); + + tb_debugfs_init(); + ret = tb_xdomain_init(); + if (ret) + goto err_debugfs; + ret = bus_register(&tb_bus_type); + if (ret) + goto err_xdomain; + + return 0; + +err_xdomain: + tb_xdomain_exit(); +err_debugfs: + tb_debugfs_exit(); + tb_test_exit(); + + return ret; +} + +void tb_domain_exit(void) +{ + bus_unregister(&tb_bus_type); + ida_destroy(&tb_domain_ida); + tb_nvm_exit(); + tb_xdomain_exit(); + tb_debugfs_exit(); + tb_test_exit(); +} |