diff options
Diffstat (limited to 'drivers/thunderbolt/xdomain.c')
| -rw-r--r-- | drivers/thunderbolt/xdomain.c | 1570 |
1 files changed, 1570 insertions, 0 deletions
diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c new file mode 100644 index 000000000000..f25d88d4552b --- /dev/null +++ b/drivers/thunderbolt/xdomain.c @@ -0,0 +1,1570 @@ +/* + * Thunderbolt XDomain discovery protocol support + * + * Copyright (C) 2017, Intel Corporation + * Authors: Michael Jamet <michael.jamet@intel.com> + * 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/kmod.h> +#include <linux/module.h> +#include <linux/utsname.h> +#include <linux/uuid.h> +#include <linux/workqueue.h> + +#include "tb.h" + +#define XDOMAIN_DEFAULT_TIMEOUT 5000 /* ms */ +#define XDOMAIN_PROPERTIES_RETRIES 60 +#define XDOMAIN_PROPERTIES_CHANGED_RETRIES 10 + +struct xdomain_request_work { + struct work_struct work; + struct tb_xdp_header *pkg; + struct tb *tb; +}; + +/* Serializes access to the properties and protocol handlers below */ +static DEFINE_MUTEX(xdomain_lock); + +/* Properties exposed to the remote domains */ +static struct tb_property_dir *xdomain_property_dir; +static u32 *xdomain_property_block; +static u32 xdomain_property_block_len; +static u32 xdomain_property_block_gen; + +/* Additional protocol handlers */ +static LIST_HEAD(protocol_handlers); + +/* UUID for XDomain discovery protocol: b638d70e-42ff-40bb-97c2-90e2c0b2ff07 */ +static const uuid_t tb_xdp_uuid = + UUID_INIT(0xb638d70e, 0x42ff, 0x40bb, + 0x97, 0xc2, 0x90, 0xe2, 0xc0, 0xb2, 0xff, 0x07); + +static bool tb_xdomain_match(const struct tb_cfg_request *req, + const struct ctl_pkg *pkg) +{ + switch (pkg->frame.eof) { + case TB_CFG_PKG_ERROR: + return true; + + case TB_CFG_PKG_XDOMAIN_RESP: { + const struct tb_xdp_header *res_hdr = pkg->buffer; + const struct tb_xdp_header *req_hdr = req->request; + + if (pkg->frame.size < req->response_size / 4) + return false; + + /* Make sure route matches */ + if ((res_hdr->xd_hdr.route_hi & ~BIT(31)) != + req_hdr->xd_hdr.route_hi) + return false; + if ((res_hdr->xd_hdr.route_lo) != req_hdr->xd_hdr.route_lo) + return false; + + /* Check that the XDomain protocol matches */ + if (!uuid_equal(&res_hdr->uuid, &req_hdr->uuid)) + return false; + + return true; + } + + default: + return false; + } +} + +static bool tb_xdomain_copy(struct tb_cfg_request *req, + const struct ctl_pkg *pkg) +{ + memcpy(req->response, pkg->buffer, req->response_size); + req->result.err = 0; + return true; +} + +static void response_ready(void *data) +{ + tb_cfg_request_put(data); +} + +static int __tb_xdomain_response(struct tb_ctl *ctl, const void *response, + size_t size, enum tb_cfg_pkg_type type) +{ + struct tb_cfg_request *req; + + req = tb_cfg_request_alloc(); + if (!req) + return -ENOMEM; + + req->match = tb_xdomain_match; + req->copy = tb_xdomain_copy; + req->request = response; + req->request_size = size; + req->request_type = type; + + return tb_cfg_request(ctl, req, response_ready, req); +} + +/** + * tb_xdomain_response() - Send a XDomain response message + * @xd: XDomain to send the message + * @response: Response to send + * @size: Size of the response + * @type: PDF type of the response + * + * This can be used to send a XDomain response message to the other + * domain. No response for the message is expected. + * + * Return: %0 in case of success and negative errno in case of failure + */ +int tb_xdomain_response(struct tb_xdomain *xd, const void *response, + size_t size, enum tb_cfg_pkg_type type) +{ + return __tb_xdomain_response(xd->tb->ctl, response, size, type); +} +EXPORT_SYMBOL_GPL(tb_xdomain_response); + +static int __tb_xdomain_request(struct tb_ctl *ctl, const void *request, + size_t request_size, enum tb_cfg_pkg_type request_type, void *response, + size_t response_size, enum tb_cfg_pkg_type response_type, + unsigned int timeout_msec) +{ + struct tb_cfg_request *req; + struct tb_cfg_result res; + + req = tb_cfg_request_alloc(); + if (!req) + return -ENOMEM; + + req->match = tb_xdomain_match; + req->copy = tb_xdomain_copy; + req->request = request; + req->request_size = request_size; + req->request_type = request_type; + req->response = response; + req->response_size = response_size; + req->response_type = response_type; + + res = tb_cfg_request_sync(ctl, req, timeout_msec); + + tb_cfg_request_put(req); + + return res.err == 1 ? -EIO : res.err; +} + +/** + * tb_xdomain_request() - Send a XDomain request + * @xd: XDomain to send the request + * @request: Request to send + * @request_size: Size of the request in bytes + * @request_type: PDF type of the request + * @response: Response is copied here + * @response_size: Expected size of the response in bytes + * @response_type: Expected PDF type of the response + * @timeout_msec: Timeout in milliseconds to wait for the response + * + * This function can be used to send XDomain control channel messages to + * the other domain. The function waits until the response is received + * or when timeout triggers. Whichever comes first. + * + * Return: %0 in case of success and negative errno in case of failure + */ +int tb_xdomain_request(struct tb_xdomain *xd, const void *request, + size_t request_size, enum tb_cfg_pkg_type request_type, + void *response, size_t response_size, + enum tb_cfg_pkg_type response_type, unsigned int timeout_msec) +{ + return __tb_xdomain_request(xd->tb->ctl, request, request_size, + request_type, response, response_size, + response_type, timeout_msec); +} +EXPORT_SYMBOL_GPL(tb_xdomain_request); + +static inline void tb_xdp_fill_header(struct tb_xdp_header *hdr, u64 route, + u8 sequence, enum tb_xdp_type type, size_t size) +{ + u32 length_sn; + + length_sn = (size - sizeof(hdr->xd_hdr)) / 4; + length_sn |= (sequence << TB_XDOMAIN_SN_SHIFT) & TB_XDOMAIN_SN_MASK; + + hdr->xd_hdr.route_hi = upper_32_bits(route); + hdr->xd_hdr.route_lo = lower_32_bits(route); + hdr->xd_hdr.length_sn = length_sn; + hdr->type = type; + memcpy(&hdr->uuid, &tb_xdp_uuid, sizeof(tb_xdp_uuid)); +} + +static int tb_xdp_handle_error(const struct tb_xdp_header *hdr) +{ + const struct tb_xdp_error_response *error; + + if (hdr->type != ERROR_RESPONSE) + return 0; + + error = (const struct tb_xdp_error_response *)hdr; + + switch (error->error) { + case ERROR_UNKNOWN_PACKET: + case ERROR_UNKNOWN_DOMAIN: + return -EIO; + case ERROR_NOT_SUPPORTED: + return -ENOTSUPP; + case ERROR_NOT_READY: + return -EAGAIN; + default: + break; + } + + return 0; +} + +static int tb_xdp_error_response(struct tb_ctl *ctl, u64 route, u8 sequence, + enum tb_xdp_error error) +{ + struct tb_xdp_error_response res; + + memset(&res, 0, sizeof(res)); + tb_xdp_fill_header(&res.hdr, route, sequence, ERROR_RESPONSE, + sizeof(res)); + res.error = error; + + return __tb_xdomain_response(ctl, &res, sizeof(res), + TB_CFG_PKG_XDOMAIN_RESP); +} + +static int tb_xdp_properties_request(struct tb_ctl *ctl, u64 route, + const uuid_t *src_uuid, const uuid_t *dst_uuid, int retry, + u32 **block, u32 *generation) +{ + struct tb_xdp_properties_response *res; + struct tb_xdp_properties req; + u16 data_len, len; + size_t total_size; + u32 *data = NULL; + int ret; + + total_size = sizeof(*res) + TB_XDP_PROPERTIES_MAX_DATA_LENGTH * 4; + res = kzalloc(total_size, GFP_KERNEL); + if (!res) + return -ENOMEM; + + memset(&req, 0, sizeof(req)); + tb_xdp_fill_header(&req.hdr, route, retry % 4, PROPERTIES_REQUEST, + sizeof(req)); + memcpy(&req.src_uuid, src_uuid, sizeof(*src_uuid)); + memcpy(&req.dst_uuid, dst_uuid, sizeof(*dst_uuid)); + + len = 0; + data_len = 0; + + do { + ret = __tb_xdomain_request(ctl, &req, sizeof(req), + TB_CFG_PKG_XDOMAIN_REQ, res, + total_size, TB_CFG_PKG_XDOMAIN_RESP, + XDOMAIN_DEFAULT_TIMEOUT); + if (ret) + goto err; + + ret = tb_xdp_handle_error(&res->hdr); + if (ret) + goto err; + + /* + * Package length includes the whole payload without the + * XDomain header. Validate first that the package is at + * least size of the response structure. + */ + len = res->hdr.xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK; + if (len < sizeof(*res) / 4) { + ret = -EINVAL; + goto err; + } + + len += sizeof(res->hdr.xd_hdr) / 4; + len -= sizeof(*res) / 4; + + if (res->offset != req.offset) { + ret = -EINVAL; + goto err; + } + + /* + * First time allocate block that has enough space for + * the whole properties block. + */ + if (!data) { + data_len = res->data_length; + if (data_len > TB_XDP_PROPERTIES_MAX_LENGTH) { + ret = -E2BIG; + goto err; + } + + data = kcalloc(data_len, sizeof(u32), GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto err; + } + } + + memcpy(data + req.offset, res->data, len * 4); + req.offset += len; + } while (!data_len || req.offset < data_len); + + *block = data; + *generation = res->generation; + + kfree(res); + + return data_len; + +err: + kfree(data); + kfree(res); + + return ret; +} + +static int tb_xdp_properties_response(struct tb *tb, struct tb_ctl *ctl, + u64 route, u8 sequence, const uuid_t *src_uuid, + const struct tb_xdp_properties *req) +{ + struct tb_xdp_properties_response *res; + size_t total_size; + u16 len; + int ret; + + /* + * Currently we expect all requests to be directed to us. The + * protocol supports forwarding, though which we might add + * support later on. + */ + if (!uuid_equal(src_uuid, &req->dst_uuid)) { + tb_xdp_error_response(ctl, route, sequence, + ERROR_UNKNOWN_DOMAIN); + return 0; + } + + mutex_lock(&xdomain_lock); + + if (req->offset >= xdomain_property_block_len) { + mutex_unlock(&xdomain_lock); + return -EINVAL; + } + + len = xdomain_property_block_len - req->offset; + len = min_t(u16, len, TB_XDP_PROPERTIES_MAX_DATA_LENGTH); + total_size = sizeof(*res) + len * 4; + + res = kzalloc(total_size, GFP_KERNEL); + if (!res) { + mutex_unlock(&xdomain_lock); + return -ENOMEM; + } + + tb_xdp_fill_header(&res->hdr, route, sequence, PROPERTIES_RESPONSE, + total_size); + res->generation = xdomain_property_block_gen; + res->data_length = xdomain_property_block_len; + res->offset = req->offset; + uuid_copy(&res->src_uuid, src_uuid); + uuid_copy(&res->dst_uuid, &req->src_uuid); + memcpy(res->data, &xdomain_property_block[req->offset], len * 4); + + mutex_unlock(&xdomain_lock); + + ret = __tb_xdomain_response(ctl, res, total_size, + TB_CFG_PKG_XDOMAIN_RESP); + + kfree(res); + return ret; +} + +static int tb_xdp_properties_changed_request(struct tb_ctl *ctl, u64 route, + int retry, const uuid_t *uuid) +{ + struct tb_xdp_properties_changed_response res; + struct tb_xdp_properties_changed req; + int ret; + + memset(&req, 0, sizeof(req)); + tb_xdp_fill_header(&req.hdr, route, retry % 4, + PROPERTIES_CHANGED_REQUEST, sizeof(req)); + uuid_copy(&req.src_uuid, uuid); + + memset(&res, 0, sizeof(res)); + ret = __tb_xdomain_request(ctl, &req, sizeof(req), + TB_CFG_PKG_XDOMAIN_REQ, &res, sizeof(res), + TB_CFG_PKG_XDOMAIN_RESP, + XDOMAIN_DEFAULT_TIMEOUT); + if (ret) + return ret; + + return tb_xdp_handle_error(&res.hdr); +} + +static int +tb_xdp_properties_changed_response(struct tb_ctl *ctl, u64 route, u8 sequence) +{ + struct tb_xdp_properties_changed_response res; + + memset(&res, 0, sizeof(res)); + tb_xdp_fill_header(&res.hdr, route, sequence, + PROPERTIES_CHANGED_RESPONSE, sizeof(res)); + return __tb_xdomain_response(ctl, &res, sizeof(res), + TB_CFG_PKG_XDOMAIN_RESP); +} + +/** + * tb_register_protocol_handler() - Register protocol handler + * @handler: Handler to register + * + * This allows XDomain service drivers to hook into incoming XDomain + * messages. After this function is called the service driver needs to + * be able to handle calls to callback whenever a package with the + * registered protocol is received. + */ +int tb_register_protocol_handler(struct tb_protocol_handler *handler) +{ + if (!handler->uuid || !handler->callback) + return -EINVAL; + if (uuid_equal(handler->uuid, &tb_xdp_uuid)) + return -EINVAL; + + mutex_lock(&xdomain_lock); + list_add_tail(&handler->list, &protocol_handlers); + mutex_unlock(&xdomain_lock); + + return 0; +} +EXPORT_SYMBOL_GPL(tb_register_protocol_handler); + +/** + * tb_unregister_protocol_handler() - Unregister protocol handler + * @handler: Handler to unregister + * + * Removes the previously registered protocol handler. + */ +void tb_unregister_protocol_handler(struct tb_protocol_handler *handler) +{ + mutex_lock(&xdomain_lock); + list_del_init(&handler->list); + mutex_unlock(&xdomain_lock); +} +EXPORT_SYMBOL_GPL(tb_unregister_protocol_handler); + +static void tb_xdp_handle_request(struct work_struct *work) +{ + struct xdomain_request_work *xw = container_of(work, typeof(*xw), work); + const struct tb_xdp_header *pkg = xw->pkg; + const struct tb_xdomain_header *xhdr = &pkg->xd_hdr; + struct tb *tb = xw->tb; + struct tb_ctl *ctl = tb->ctl; + const uuid_t *uuid; + int ret = 0; + u32 sequence; + u64 route; + + route = ((u64)xhdr->route_hi << 32 | xhdr->route_lo) & ~BIT_ULL(63); + sequence = xhdr->length_sn & TB_XDOMAIN_SN_MASK; + sequence >>= TB_XDOMAIN_SN_SHIFT; + + mutex_lock(&tb->lock); + if (tb->root_switch) + uuid = tb->root_switch->uuid; + else + uuid = NULL; + mutex_unlock(&tb->lock); + + if (!uuid) { + tb_xdp_error_response(ctl, route, sequence, ERROR_NOT_READY); + goto out; + } + + switch (pkg->type) { + case PROPERTIES_REQUEST: + ret = tb_xdp_properties_response(tb, ctl, route, sequence, uuid, + (const struct tb_xdp_properties *)pkg); + break; + + case PROPERTIES_CHANGED_REQUEST: { + const struct tb_xdp_properties_changed *xchg = + (const struct tb_xdp_properties_changed *)pkg; + struct tb_xdomain *xd; + + ret = tb_xdp_properties_changed_response(ctl, route, sequence); + + /* + * Since the properties have been changed, let's update + * the xdomain related to this connection as well in + * case there is a change in services it offers. + */ + xd = tb_xdomain_find_by_uuid_locked(tb, &xchg->src_uuid); + if (xd) { + queue_delayed_work(tb->wq, &xd->get_properties_work, + msecs_to_jiffies(50)); + tb_xdomain_put(xd); + } + + break; + } + + default: + break; + } + + if (ret) { + tb_warn(tb, "failed to send XDomain response for %#x\n", + pkg->type); + } + +out: + kfree(xw->pkg); + kfree(xw); +} + +static void +tb_xdp_schedule_request(struct tb *tb, const struct tb_xdp_header *hdr, + size_t size) +{ + struct xdomain_request_work *xw; + + xw = kmalloc(sizeof(*xw), GFP_KERNEL); + if (!xw) + return; + + INIT_WORK(&xw->work, tb_xdp_handle_request); + xw->pkg = kmemdup(hdr, size, GFP_KERNEL); + xw->tb = tb; + + queue_work(tb->wq, &xw->work); +} + +/** + * tb_register_service_driver() - Register XDomain service driver + * @drv: Driver to register + * + * Registers new service driver from @drv to the bus. + */ +int tb_register_service_driver(struct tb_service_driver *drv) +{ + drv->driver.bus = &tb_bus_type; + return driver_register(&drv->driver); +} +EXPORT_SYMBOL_GPL(tb_register_service_driver); + +/** + * tb_unregister_service_driver() - Unregister XDomain service driver + * @xdrv: Driver to unregister + * + * Unregisters XDomain service driver from the bus. + */ +void tb_unregister_service_driver(struct tb_service_driver *drv) +{ + driver_unregister(&drv->driver); +} +EXPORT_SYMBOL_GPL(tb_unregister_service_driver); + +static ssize_t key_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + + /* + * It should be null terminated but anything else is pretty much + * allowed. + */ + return sprintf(buf, "%*pEp\n", (int)strlen(svc->key), svc->key); +} +static DEVICE_ATTR_RO(key); + +static int get_modalias(struct tb_service *svc, char *buf, size_t size) +{ + return snprintf(buf, size, "tbsvc:k%sp%08Xv%08Xr%08X", svc->key, + svc->prtcid, svc->prtcvers, svc->prtcrevs); +} + +static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + + /* Full buffer size except new line and null termination */ + get_modalias(svc, buf, PAGE_SIZE - 2); + return sprintf(buf, "%s\n", buf); +} +static DEVICE_ATTR_RO(modalias); + +static ssize_t prtcid_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + + return sprintf(buf, "%u\n", svc->prtcid); +} +static DEVICE_ATTR_RO(prtcid); + +static ssize_t prtcvers_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + + return sprintf(buf, "%u\n", svc->prtcvers); +} +static DEVICE_ATTR_RO(prtcvers); + +static ssize_t prtcrevs_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + + return sprintf(buf, "%u\n", svc->prtcrevs); +} +static DEVICE_ATTR_RO(prtcrevs); + +static ssize_t prtcstns_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + + return sprintf(buf, "0x%08x\n", svc->prtcstns); +} +static DEVICE_ATTR_RO(prtcstns); + +static struct attribute *tb_service_attrs[] = { + &dev_attr_key.attr, + &dev_attr_modalias.attr, + &dev_attr_prtcid.attr, + &dev_attr_prtcvers.attr, + &dev_attr_prtcrevs.attr, + &dev_attr_prtcstns.attr, + NULL, +}; + +static struct attribute_group tb_service_attr_group = { + .attrs = tb_service_attrs, +}; + +static const struct attribute_group *tb_service_attr_groups[] = { + &tb_service_attr_group, + NULL, +}; + +static int tb_service_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + char modalias[64]; + + get_modalias(svc, modalias, sizeof(modalias)); + return add_uevent_var(env, "MODALIAS=%s", modalias); +} + +static void tb_service_release(struct device *dev) +{ + struct tb_service *svc = container_of(dev, struct tb_service, dev); + struct tb_xdomain *xd = tb_service_parent(svc); + + ida_simple_remove(&xd->service_ids, svc->id); + kfree(svc->key); + kfree(svc); +} + +struct device_type tb_service_type = { + .name = "thunderbolt_service", + .groups = tb_service_attr_groups, + .uevent = tb_service_uevent, + .release = tb_service_release, +}; +EXPORT_SYMBOL_GPL(tb_service_type); + +static int remove_missing_service(struct device *dev, void *data) +{ + struct tb_xdomain *xd = data; + struct tb_service *svc; + + svc = tb_to_service(dev); + if (!svc) + return 0; + + if (!tb_property_find(xd->properties, svc->key, + TB_PROPERTY_TYPE_DIRECTORY)) + device_unregister(dev); + + return 0; +} + +static int find_service(struct device *dev, void *data) +{ + const struct tb_property *p = data; + struct tb_service *svc; + + svc = tb_to_service(dev); + if (!svc) + return 0; + + return !strcmp(svc->key, p->key); +} + +static int populate_service(struct tb_service *svc, + struct tb_property *property) +{ + struct tb_property_dir *dir = property->value.dir; + struct tb_property *p; + + /* Fill in standard properties */ + p = tb_property_find(dir, "prtcid", TB_PROPERTY_TYPE_VALUE); + if (p) + svc->prtcid = p->value.immediate; + p = tb_property_find(dir, "prtcvers", TB_PROPERTY_TYPE_VALUE); + if (p) + svc->prtcvers = p->value.immediate; + p = tb_property_find(dir, "prtcrevs", TB_PROPERTY_TYPE_VALUE); + if (p) + svc->prtcrevs = p->value.immediate; + p = tb_property_find(dir, "prtcstns", TB_PROPERTY_TYPE_VALUE); + if (p) + svc->prtcstns = p->value.immediate; + + svc->key = kstrdup(property->key, GFP_KERNEL); + if (!svc->key) + return -ENOMEM; + + return 0; +} + +static void enumerate_services(struct tb_xdomain *xd) +{ + struct tb_service *svc; + struct tb_property *p; + struct device *dev; + + /* + * First remove all services that are not available anymore in + * the updated property block. + */ + device_for_each_child_reverse(&xd->dev, xd, remove_missing_service); + + /* Then re-enumerate properties creating new services as we go */ + tb_property_for_each(xd->properties, p) { + if (p->type != TB_PROPERTY_TYPE_DIRECTORY) + continue; + + /* If the service exists already we are fine */ + dev = device_find_child(&xd->dev, p, find_service); + if (dev) { + put_device(dev); + continue; + } + + svc = kzalloc(sizeof(*svc), GFP_KERNEL); + if (!svc) + break; + + if (populate_service(svc, p)) { + kfree(svc); + break; + } + + svc->id = ida_simple_get(&xd->service_ids, 0, 0, GFP_KERNEL); + svc->dev.bus = &tb_bus_type; + svc->dev.type = &tb_service_type; + svc->dev.parent = &xd->dev; + dev_set_name(&svc->dev, "%s.%d", dev_name(&xd->dev), svc->id); + + if (device_register(&svc->dev)) { + put_device(&svc->dev); + break; + } + } +} + +static int populate_properties(struct tb_xdomain *xd, + struct tb_property_dir *dir) +{ + const struct tb_property *p; + + /* Required properties */ + p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_VALUE); + if (!p) + return -EINVAL; + xd->device = p->value.immediate; + + p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_VALUE); + if (!p) + return -EINVAL; + xd->vendor = p->value.immediate; + + kfree(xd->device_name); + xd->device_name = NULL; + kfree(xd->vendor_name); + xd->vendor_name = NULL; + + /* Optional properties */ + p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_TEXT); + if (p) + xd->device_name = kstrdup(p->value.text, GFP_KERNEL); + p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_TEXT); + if (p) + xd->vendor_name = kstrdup(p->value.text, GFP_KERNEL); + + return 0; +} + +/* Called with @xd->lock held */ +static void tb_xdomain_restore_paths(struct tb_xdomain *xd) +{ + if (!xd->resume) + return; + + xd->resume = false; + if (xd->transmit_path) { + dev_dbg(&xd->dev, "re-establishing DMA path\n"); + tb_domain_approve_xdomain_paths(xd->tb, xd); + } +} + +static void tb_xdomain_get_properties(struct work_struct *work) +{ + struct tb_xdomain *xd = container_of(work, typeof(*xd), + get_properties_work.work); + struct tb_property_dir *dir; + struct tb *tb = xd->tb; + bool update = false; + u32 *block = NULL; + u32 gen = 0; + int ret; + + ret = tb_xdp_properties_request(tb->ctl, xd->route, xd->local_uuid, + xd->remote_uuid, xd->properties_retries, + &block, &gen); + if (ret < 0) { + if (xd->properties_retries-- > 0) { + queue_delayed_work(xd->tb->wq, &xd->get_properties_work, + msecs_to_jiffies(1000)); + } else { + /* Give up now */ + dev_err(&xd->dev, + "failed read XDomain properties from %pUb\n", + xd->remote_uuid); + } + return; + } + + xd->properties_retries = XDOMAIN_PROPERTIES_RETRIES; + + mutex_lock(&xd->lock); + + /* Only accept newer generation properties */ + if (xd->properties && gen <= xd->property_block_gen) { + /* + * On resume it is likely that the properties block is + * not changed (unless the other end added or removed + * services). However, we need to make sure the existing + * DMA paths are restored properly. + */ + tb_xdomain_restore_paths(xd); + goto err_free_block; + } + + dir = tb_property_parse_dir(block, ret); + if (!dir) { + dev_err(&xd->dev, "failed to parse XDomain properties\n"); + goto err_free_block; + } + + ret = populate_properties(xd, dir); + if (ret) { + dev_err(&xd->dev, "missing XDomain properties in response\n"); + goto err_free_dir; + } + + /* Release the existing one */ + if (xd->properties) { + tb_property_free_dir(xd->properties); + update = true; + } + + xd->properties = dir; + xd->property_block_gen = gen; + + tb_xdomain_restore_paths(xd); + + mutex_unlock(&xd->lock); + + kfree(block); + + /* + * Now the device should be ready enough so we can add it to the + * bus and let userspace know about it. If the device is already + * registered, we notify the userspace that it has changed. + */ + if (!update) { + if (device_add(&xd->dev)) { + dev_err(&xd->dev, "failed to add XDomain device\n"); + return; + } + } else { + kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE); + } + + enumerate_services(xd); + return; + +err_free_dir: + tb_property_free_dir(dir); +err_free_block: + kfree(block); + mutex_unlock(&xd->lock); +} + +static void tb_xdomain_properties_changed(struct work_struct *work) +{ + struct tb_xdomain *xd = container_of(work, typeof(*xd), + properties_changed_work.work); + int ret; + + ret = tb_xdp_properties_changed_request(xd->tb->ctl, xd->route, + xd->properties_changed_retries, xd->local_uuid); + if (ret) { + if (xd->properties_changed_retries-- > 0) + queue_delayed_work(xd->tb->wq, + &xd->properties_changed_work, + msecs_to_jiffies(1000)); + return; + } + + xd->properties_changed_retries = XDOMAIN_PROPERTIES_CHANGED_RETRIES; +} + +static ssize_t device_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev); + + return sprintf(buf, "%#x\n", xd->device); +} +static DEVICE_ATTR_RO(device); + +static ssize_t +device_name_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev); + int ret; + + if (mutex_lock_interruptible(&xd->lock)) + return -ERESTARTSYS; + ret = sprintf(buf, "%s\n", xd->device_name ? xd->device_name : ""); + mutex_unlock(&xd->lock); + + return ret; +} +static DEVICE_ATTR_RO(device_name); + +static ssize_t vendor_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev); + + return sprintf(buf, "%#x\n", xd->vendor); +} +static DEVICE_ATTR_RO(vendor); + +static ssize_t +vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev); + int ret; + + if (mutex_lock_interruptible(&xd->lock)) + return -ERESTARTSYS; + ret = sprintf(buf, "%s\n", xd->vendor_name ? xd->vendor_name : ""); + mutex_unlock(&xd->lock); + + return ret; +} +static DEVICE_ATTR_RO(vendor_name); + +static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev); + + return sprintf(buf, "%pUb\n", xd->remote_uuid); +} +static DEVICE_ATTR_RO(unique_id); + +static struct attribute *xdomain_attrs[] = { + &dev_attr_device.attr, + &dev_attr_device_name.attr, + &dev_attr_unique_id.attr, + &dev_attr_vendor.attr, + &dev_attr_vendor_name.attr, + NULL, +}; + +static struct attribute_group xdomain_attr_group = { + .attrs = xdomain_attrs, +}; + +static const struct attribute_group *xdomain_attr_groups[] = { + &xdomain_attr_group, + NULL, +}; + +static void tb_xdomain_release(struct device *dev) +{ + struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev); + + put_device(xd->dev.parent); + + tb_property_free_dir(xd->properties); + ida_destroy(&xd->service_ids); + + kfree(xd->local_uuid); + kfree(xd->remote_uuid); + kfree(xd->device_name); + kfree(xd->vendor_name); + kfree(xd); +} + +static void start_handshake(struct tb_xdomain *xd) +{ + xd->properties_retries = XDOMAIN_PROPERTIES_RETRIES; + xd->properties_changed_retries = XDOMAIN_PROPERTIES_CHANGED_RETRIES; + + /* Start exchanging properties with the other host */ + queue_delayed_work(xd->tb->wq, &xd->properties_changed_work, + msecs_to_jiffies(100)); + queue_delayed_work(xd->tb->wq, &xd->get_properties_work, + msecs_to_jiffies(1000)); +} + +static void stop_handshake(struct tb_xdomain *xd) +{ + xd->properties_retries = 0; + xd->properties_changed_retries = 0; + + cancel_delayed_work_sync(&xd->get_properties_work); + cancel_delayed_work_sync(&xd->properties_changed_work); +} + +static int __maybe_unused tb_xdomain_suspend(struct device *dev) +{ + stop_handshake(tb_to_xdomain(dev)); + return 0; +} + +static int __maybe_unused tb_xdomain_resume(struct device *dev) +{ + struct tb_xdomain *xd = tb_to_xdomain(dev); + + /* + * Ask tb_xdomain_get_properties() restore any existing DMA + * paths after properties are re-read. + */ + xd->resume = true; + start_handshake(xd); + + return 0; +} + +static const struct dev_pm_ops tb_xdomain_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(tb_xdomain_suspend, tb_xdomain_resume) +}; + +struct device_type tb_xdomain_type = { + .name = "thunderbolt_xdomain", + .release = tb_xdomain_release, + .pm = &tb_xdomain_pm_ops, +}; +EXPORT_SYMBOL_GPL(tb_xdomain_type); + +/** + * tb_xdomain_alloc() - Allocate new XDomain object + * @tb: Domain where the XDomain belongs + * @parent: Parent device (the switch through the connection to the + * other domain is reached). + * @route: Route string used to reach the other domain + * @local_uuid: Our local domain UUID + * @remote_uuid: UUID of the other domain + * + * Allocates new XDomain structure and returns pointer to that. The + * object must be released by calling tb_xdomain_put(). + */ +struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent, + u64 route, const uuid_t *local_uuid, + const uuid_t *remote_uuid) +{ + struct tb_xdomain *xd; + + xd = kzalloc(sizeof(*xd), GFP_KERNEL); + if (!xd) + return NULL; + + xd->tb = tb; + xd->route = route; + ida_init(&xd->service_ids); + mutex_init(&xd->lock); + INIT_DELAYED_WORK(&xd->get_properties_work, tb_xdomain_get_properties); + INIT_DELAYED_WORK(&xd->properties_changed_work, + tb_xdomain_properties_changed); + + xd->local_uuid = kmemdup(local_uuid, sizeof(uuid_t), GFP_KERNEL); + if (!xd->local_uuid) + goto err_free; + + xd->remote_uuid = kmemdup(remote_uuid, sizeof(uuid_t), GFP_KERNEL); + if (!xd->remote_uuid) + goto err_free_local_uuid; + + device_initialize(&xd->dev); + xd->dev.parent = get_device(parent); + xd->dev.bus = &tb_bus_type; + xd->dev.type = &tb_xdomain_type; + xd->dev.groups = xdomain_attr_groups; + dev_set_name(&xd->dev, "%u-%llx", tb->index, route); + + return xd; + +err_free_local_uuid: + kfree(xd->local_uuid); +err_free: + kfree(xd); + + return NULL; +} + +/** + * tb_xdomain_add() - Add XDomain to the bus + * @xd: XDomain to add + * + * This function starts XDomain discovery protocol handshake and + * eventually adds the XDomain to the bus. After calling this function + * the caller needs to call tb_xdomain_remove() in order to remove and + * release the object regardless whether the handshake succeeded or not. + */ +void tb_xdomain_add(struct tb_xdomain *xd) +{ + /* Start exchanging properties with the other host */ + start_handshake(xd); +} + +static int unregister_service(struct device *dev, void *data) +{ + device_unregister(dev); + return 0; +} + +/** + * tb_xdomain_remove() - Remove XDomain from the bus + * @xd: XDomain to remove + * + * This will stop all ongoing configuration work and remove the XDomain + * along with any services from the bus. When the last reference to @xd + * is released the object will be released as well. + */ +void tb_xdomain_remove(struct tb_xdomain *xd) +{ + stop_handshake(xd); + + device_for_each_child_reverse(&xd->dev, xd, unregister_service); + + if (!device_is_registered(&xd->dev)) + put_device(&xd->dev); + else + device_unregister(&xd->dev); +} + +/** + * tb_xdomain_enable_paths() - Enable DMA paths for XDomain connection + * @xd: XDomain connection + * @transmit_path: HopID of the transmit path the other end is using to + * send packets + * @transmit_ring: DMA ring used to receive packets from the other end + * @receive_path: HopID of the receive path the other end is using to + * receive packets + * @receive_ring: DMA ring used to send packets to the other end + * + * The function enables DMA paths accordingly so that after successful + * return the caller can send and receive packets using high-speed DMA + * path. + * + * Return: %0 in case of success and negative errno in case of error + */ +int tb_xdomain_enable_paths(struct tb_xdomain *xd, u16 transmit_path, + u16 transmit_ring, u16 receive_path, + u16 receive_ring) +{ + int ret; + + mutex_lock(&xd->lock); + + if (xd->transmit_path) { + ret = xd->transmit_path == transmit_path ? 0 : -EBUSY; + goto exit_unlock; + } + + xd->transmit_path = transmit_path; + xd->transmit_ring = transmit_ring; + xd->receive_path = receive_path; + xd->receive_ring = receive_ring; + + ret = tb_domain_approve_xdomain_paths(xd->tb, xd); + +exit_unlock: + mutex_unlock(&xd->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(tb_xdomain_enable_paths); + +/** + * tb_xdomain_disable_paths() - Disable DMA paths for XDomain connection + * @xd: XDomain connection + * + * This does the opposite of tb_xdomain_enable_paths(). After call to + * this the caller is not expected to use the rings anymore. + * + * Return: %0 in case of success and negative errno in case of error + */ +int tb_xdomain_disable_paths(struct tb_xdomain *xd) +{ + int ret = 0; + + mutex_lock(&xd->lock); + if (xd->transmit_path) { + xd->transmit_path = 0; + xd->transmit_ring = 0; + xd->receive_path = 0; + xd->receive_ring = 0; + + ret = tb_domain_disconnect_xdomain_paths(xd->tb, xd); + } + mutex_unlock(&xd->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(tb_xdomain_disable_paths); + +struct tb_xdomain_lookup { + const uuid_t *uuid; + u8 link; + u8 depth; +}; + +static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw, + const struct tb_xdomain_lookup *lookup) +{ + int i; + + for (i = 1; i <= sw->config.max_port_number; i++) { + struct tb_port *port = &sw->ports[i]; + struct tb_xdomain *xd; + + if (tb_is_upstream_port(port)) + continue; + + if (port->xdomain) { + xd = port->xdomain; + + if (lookup->uuid) { + if (uuid_equal(xd->remote_uuid, lookup->uuid)) + return xd; + } else if (lookup->link == xd->link && + lookup->depth == xd->depth) { + return xd; + } + } else if (port->remote) { + xd = switch_find_xdomain(port->remote->sw, lookup); + if (xd) + return xd; + } + } + + return NULL; +} + +/** + * tb_xdomain_find_by_uuid() - Find an XDomain by UUID + * @tb: Domain where the XDomain belongs to + * @uuid: UUID to look for + * + * Finds XDomain by walking through the Thunderbolt topology below @tb. + * The returned XDomain will have its reference count increased so the + * caller needs to call tb_xdomain_put() when it is done with the + * object. + * + * This will find all XDomains including the ones that are not yet added + * to the bus (handshake is still in progress). + * + * The caller needs to hold @tb->lock. + */ +struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid) +{ + struct tb_xdomain_lookup lookup; + struct tb_xdomain *xd; + + memset(&lookup, 0, sizeof(lookup)); + lookup.uuid = uuid; + + xd = switch_find_xdomain(tb->root_switch, &lookup); + if (xd) { + get_device(&xd->dev); + return xd; + } + + return NULL; +} +EXPORT_SYMBOL_GPL(tb_xdomain_find_by_uuid); + +/** + * tb_xdomain_find_by_link_depth() - Find an XDomain by link and depth + * @tb: Domain where the XDomain belongs to + * @link: Root switch link number + * @depth: Depth in the link + * + * Finds XDomain by walking through the Thunderbolt topology below @tb. + * The returned XDomain will have its reference count increased so the + * caller needs to call tb_xdomain_put() when it is done with the + * object. + * + * This will find all XDomains including the ones that are not yet added + * to the bus (handshake is still in progress). + * + * The caller needs to hold @tb->lock. + */ +struct tb_xdomain *tb_xdomain_find_by_link_depth(struct tb *tb, u8 link, + u8 depth) +{ + struct tb_xdomain_lookup lookup; + struct tb_xdomain *xd; + + memset(&lookup, 0, sizeof(lookup)); + lookup.link = link; + lookup.depth = depth; + + xd = switch_find_xdomain(tb->root_switch, &lookup); + if (xd) { + get_device(&xd->dev); + return xd; + } + + return NULL; +} + +bool tb_xdomain_handle_request(struct tb *tb, enum tb_cfg_pkg_type type, + const void *buf, size_t size) +{ + const struct tb_protocol_handler *handler, *tmp; + const struct tb_xdp_header *hdr = buf; + unsigned int length; + int ret = 0; + + /* We expect the packet is at least size of the header */ + length = hdr->xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK; + if (length != size / 4 - sizeof(hdr->xd_hdr) / 4) + return true; + if (length < sizeof(*hdr) / 4 - sizeof(hdr->xd_hdr) / 4) + return true; + + /* + * Handle XDomain discovery protocol packets directly here. For + * other protocols (based on their UUID) we call registered + * handlers in turn. + */ + if (uuid_equal(&hdr->uuid, &tb_xdp_uuid)) { + if (type == TB_CFG_PKG_XDOMAIN_REQ) { + tb_xdp_schedule_request(tb, hdr, size); + return true; + } + return false; + } + + mutex_lock(&xdomain_lock); + list_for_each_entry_safe(handler, tmp, &protocol_handlers, list) { + if (!uuid_equal(&hdr->uuid, handler->uuid)) + continue; + + mutex_unlock(&xdomain_lock); + ret = handler->callback(buf, size, handler->data); + mutex_lock(&xdomain_lock); + + if (ret) + break; + } + mutex_unlock(&xdomain_lock); + + return ret > 0; +} + +static int rebuild_property_block(void) +{ + u32 *block, len; + int ret; + + ret = tb_property_format_dir(xdomain_property_dir, NULL, 0); + if (ret < 0) + return ret; + + len = ret; + + block = kcalloc(len, sizeof(u32), GFP_KERNEL); + if (!block) + return -ENOMEM; + + ret = tb_property_format_dir(xdomain_property_dir, block, len); + if (ret) { + kfree(block); + return ret; + } + + kfree(xdomain_property_block); + xdomain_property_block = block; + xdomain_property_block_len = len; + xdomain_property_block_gen++; + + return 0; +} + +static int update_xdomain(struct device *dev, void *data) +{ + struct tb_xdomain *xd; + + xd = tb_to_xdomain(dev); + if (xd) { + queue_delayed_work(xd->tb->wq, &xd->properties_changed_work, + msecs_to_jiffies(50)); + } + + return 0; +} + +static void update_all_xdomains(void) +{ + bus_for_each_dev(&tb_bus_type, NULL, NULL, update_xdomain); +} + +static bool remove_directory(const char *key, const struct tb_property_dir *dir) +{ + struct tb_property *p; + + p = tb_property_find(xdomain_property_dir, key, + TB_PROPERTY_TYPE_DIRECTORY); + if (p && p->value.dir == dir) { + tb_property_remove(p); + return true; + } + return false; +} + +/** + * tb_register_property_dir() - Register property directory to the host + * @key: Key (name) of the directory to add + * @dir: Directory to add + * + * Service drivers can use this function to add new property directory + * to the host available properties. The other connected hosts are + * notified so they can re-read properties of this host if they are + * interested. + * + * Return: %0 on success and negative errno on failure + */ +int tb_register_property_dir(const char *key, struct tb_property_dir *dir) +{ + int ret; + + if (WARN_ON(!xdomain_property_dir)) + return -EAGAIN; + + if (!key || strlen(key) > 8) + return -EINVAL; + + mutex_lock(&xdomain_lock); + if (tb_property_find(xdomain_property_dir, key, + TB_PROPERTY_TYPE_DIRECTORY)) { + ret = -EEXIST; + goto err_unlock; + } + + ret = tb_property_add_dir(xdomain_property_dir, key, dir); + if (ret) + goto err_unlock; + + ret = rebuild_property_block(); + if (ret) { + remove_directory(key, dir); + goto err_unlock; + } + + mutex_unlock(&xdomain_lock); + update_all_xdomains(); + return 0; + +err_unlock: + mutex_unlock(&xdomain_lock); + return ret; +} +EXPORT_SYMBOL_GPL(tb_register_property_dir); + +/** + * tb_unregister_property_dir() - Removes property directory from host + * @key: Key (name) of the directory + * @dir: Directory to remove + * + * This will remove the existing directory from this host and notify the + * connected hosts about the change. + */ +void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir) +{ + int ret = 0; + + mutex_lock(&xdomain_lock); + if (remove_directory(key, dir)) + ret = rebuild_property_block(); + mutex_unlock(&xdomain_lock); + + if (!ret) + update_all_xdomains(); +} +EXPORT_SYMBOL_GPL(tb_unregister_property_dir); + +int tb_xdomain_init(void) +{ + int ret; + + xdomain_property_dir = tb_property_create_dir(NULL); + if (!xdomain_property_dir) + return -ENOMEM; + + /* + * Initialize standard set of properties without any service + * directories. Those will be added by service drivers + * themselves when they are loaded. + */ + tb_property_add_immediate(xdomain_property_dir, "vendorid", + PCI_VENDOR_ID_INTEL); + tb_property_add_text(xdomain_property_dir, "vendorid", "Intel Corp."); + tb_property_add_immediate(xdomain_property_dir, "deviceid", 0x1); + tb_property_add_text(xdomain_property_dir, "deviceid", + utsname()->nodename); + tb_property_add_immediate(xdomain_property_dir, "devicerv", 0x80000100); + + ret = rebuild_property_block(); + if (ret) { + tb_property_free_dir(xdomain_property_dir); + xdomain_property_dir = NULL; + } + + return ret; +} + +void tb_xdomain_exit(void) +{ + kfree(xdomain_property_block); + tb_property_free_dir(xdomain_property_dir); +} |