1 files changed, 456 insertions, 0 deletions
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c
new file mode 100644
index 000000000000..9f2dcd48974d
--- /dev/null
+++ b/drivers/thunderbolt/domain.c
@@ -0,0 +1,456 @@
+/*
+ * Thunderbolt bus support
+ *
+ * Copyright (C) 2017, Intel Corporation
+ * Author:  Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <crypto/hash.h>
+
+#include "tb.h"
+
+static DEFINE_IDA(tb_domain_ida);
+
+static const char * const tb_security_names[] = {
+	[TB_SECURITY_NONE] = "none",
+	[TB_SECURITY_USER] = "user",
+	[TB_SECURITY_SECURE] = "secure",
+	[TB_SECURITY_DPONLY] = "dponly",
+};
+
+static ssize_t security_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct tb *tb = container_of(dev, struct tb, dev);
+
+	return sprintf(buf, "%s\n", tb_security_names[tb->security_level]);
+}
+static DEVICE_ATTR_RO(security);
+
+static struct attribute *domain_attrs[] = {
+	&dev_attr_security.attr,
+	NULL,
+};
+
+static struct attribute_group domain_attr_group = {
+	.attrs = domain_attrs,
+};
+
+static const struct attribute_group *domain_attr_groups[] = {
+	&domain_attr_group,
+	NULL,
+};
+
+struct bus_type tb_bus_type = {
+	.name = "thunderbolt",
+};
+
+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 void 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;
+	}
+
+	tb->cm_ops->handle_event(tb, type, buf, size);
+}
+
+/**
+ * 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);
+
+	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)
+{
+	int ret;
+
+	mutex_lock(&tb->lock);
+	if (tb->cm_ops->suspend) {
+		ret = tb->cm_ops->suspend(tb);
+		if (ret) {
+			mutex_unlock(&tb->lock);
+			return ret;
+		}
+	}
+	mutex_unlock(&tb->lock);
+	return 0;
+}
+
+void tb_domain_complete(struct tb *tb)
+{
+	mutex_lock(&tb->lock);
+	if (tb->cm_ops->complete)
+		tb->cm_ops->complete(tb);
+	mutex_unlock(&tb->lock);
+}
+
+/**
+ * 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;
+	shash->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+	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);
+}
+
+int tb_domain_init(void)
+{
+	return bus_register(&tb_bus_type);
+}
+
+void tb_domain_exit(void)
+{
+	bus_unregister(&tb_bus_type);
+	ida_destroy(&tb_domain_ida);
+	tb_switch_exit();
+}