diff options
Diffstat (limited to 'drivers/uwb/wlp/eda.c')
| -rw-r--r-- | drivers/uwb/wlp/eda.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/drivers/uwb/wlp/eda.c b/drivers/uwb/wlp/eda.c new file mode 100644 index 000000000000..cdfe8dfc4340 --- /dev/null +++ b/drivers/uwb/wlp/eda.c @@ -0,0 +1,449 @@ +/* + * WUSB Wire Adapter: WLP interface + * Ethernet to device address cache + * + * Copyright (C) 2005-2006 Intel Corporation + * Inaky Perez-Gonzalez <inaky.perez-gonzalez@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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * + * We need to be able to map ethernet addresses to device addresses + * and back because there is not explicit relationship between the eth + * addresses used in the ETH frames and the device addresses (no, it + * would not have been simpler to force as ETH address the MBOA MAC + * address...no, not at all :). + * + * A device has one MBOA MAC address and one device address. It is possible + * for a device to have more than one virtual MAC address (although a + * virtual address can be the same as the MBOA MAC address). The device + * address is guaranteed to be unique among the devices in the extended + * beacon group (see ECMA 17.1.1). We thus use the device address as index + * to this cache. We do allow searching based on virtual address as this + * is how Ethernet frames will be addressed. + * + * We need to support virtual EUI-48. Although, right now the virtual + * EUI-48 will always be the same as the MAC SAP address. The EDA cache + * entry thus contains a MAC SAP address as well as the virtual address + * (used to map the network stack address to a neighbor). When we move + * to support more than one virtual MAC on a host then this organization + * will have to change. Perhaps a neighbor has a list of WSSs, each with a + * tag and virtual EUI-48. + * + * On data transmission + * it is used to determine if the neighbor is connected and what WSS it + * belongs to. With this we know what tag to add to the WLP frame. Storing + * the WSS in the EDA cache may be overkill because we only support one + * WSS. Hopefully we will support more than one WSS at some point. + * On data reception it is used to determine the WSS based on + * the tag and address of the transmitting neighbor. + */ + +#define D_LOCAL 5 +#include <linux/netdevice.h> +#include <linux/uwb/debug.h> +#include <linux/etherdevice.h> +#include <linux/wlp.h> +#include "wlp-internal.h" + + +/* FIXME: cache is not purged, only on device close */ + +/* FIXME: does not scale, change to dynamic array */ + +/* + * Initialize the EDA cache + * + * @returns 0 if ok, < 0 errno code on error + * + * Call when the interface is being brought up + * + * NOTE: Keep it as a separate function as the implementation will + * change and be more complex. + */ +void wlp_eda_init(struct wlp_eda *eda) +{ + INIT_LIST_HEAD(&eda->cache); + spin_lock_init(&eda->lock); +} + +/* + * Release the EDA cache + * + * @returns 0 if ok, < 0 errno code on error + * + * Called when the interface is brought down + */ +void wlp_eda_release(struct wlp_eda *eda) +{ + unsigned long flags; + struct wlp_eda_node *itr, *next; + + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry_safe(itr, next, &eda->cache, list_node) { + list_del(&itr->list_node); + kfree(itr); + } + spin_unlock_irqrestore(&eda->lock, flags); +} + +/* + * Add an address mapping + * + * @returns 0 if ok, < 0 errno code on error + * + * An address mapping is initially created when the neighbor device is seen + * for the first time (it is "onair"). At this time the neighbor is not + * connected or associated with a WSS so we only populate the Ethernet and + * Device address fields. + * + */ +int wlp_eda_create_node(struct wlp_eda *eda, + const unsigned char eth_addr[ETH_ALEN], + const struct uwb_dev_addr *dev_addr) +{ + int result = 0; + struct wlp_eda_node *itr; + unsigned long flags; + + BUG_ON(dev_addr == NULL || eth_addr == NULL); + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry(itr, &eda->cache, list_node) { + if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) { + printk(KERN_ERR "EDA cache already contains entry " + "for neighbor %02x:%02x\n", + dev_addr->data[1], dev_addr->data[0]); + result = -EEXIST; + goto out_unlock; + } + } + itr = kzalloc(sizeof(*itr), GFP_ATOMIC); + if (itr != NULL) { + memcpy(itr->eth_addr, eth_addr, sizeof(itr->eth_addr)); + itr->dev_addr = *dev_addr; + list_add(&itr->list_node, &eda->cache); + } else + result = -ENOMEM; +out_unlock: + spin_unlock_irqrestore(&eda->lock, flags); + return result; +} + +/* + * Remove entry from EDA cache + * + * This is done when the device goes off air. + */ +void wlp_eda_rm_node(struct wlp_eda *eda, const struct uwb_dev_addr *dev_addr) +{ + struct wlp_eda_node *itr, *next; + unsigned long flags; + + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry_safe(itr, next, &eda->cache, list_node) { + if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) { + list_del(&itr->list_node); + kfree(itr); + break; + } + } + spin_unlock_irqrestore(&eda->lock, flags); +} + +/* + * Update an address mapping + * + * @returns 0 if ok, < 0 errno code on error + */ +int wlp_eda_update_node(struct wlp_eda *eda, + const struct uwb_dev_addr *dev_addr, + struct wlp_wss *wss, + const unsigned char virt_addr[ETH_ALEN], + const u8 tag, const enum wlp_wss_connect state) +{ + int result = -ENOENT; + struct wlp_eda_node *itr; + unsigned long flags; + + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry(itr, &eda->cache, list_node) { + if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) { + /* Found it, update it */ + itr->wss = wss; + memcpy(itr->virt_addr, virt_addr, + sizeof(itr->virt_addr)); + itr->tag = tag; + itr->state = state; + result = 0; + goto out_unlock; + } + } + /* Not found */ +out_unlock: + spin_unlock_irqrestore(&eda->lock, flags); + return result; +} + +/* + * Update only state field of an address mapping + * + * @returns 0 if ok, < 0 errno code on error + */ +int wlp_eda_update_node_state(struct wlp_eda *eda, + const struct uwb_dev_addr *dev_addr, + const enum wlp_wss_connect state) +{ + int result = -ENOENT; + struct wlp_eda_node *itr; + unsigned long flags; + + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry(itr, &eda->cache, list_node) { + if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) { + /* Found it, update it */ + itr->state = state; + result = 0; + goto out_unlock; + } + } + /* Not found */ +out_unlock: + spin_unlock_irqrestore(&eda->lock, flags); + return result; +} + +/* + * Return contents of EDA cache entry + * + * @dev_addr: index to EDA cache + * @eda_entry: pointer to where contents of EDA cache will be copied + */ +int wlp_copy_eda_node(struct wlp_eda *eda, struct uwb_dev_addr *dev_addr, + struct wlp_eda_node *eda_entry) +{ + int result = -ENOENT; + struct wlp_eda_node *itr; + unsigned long flags; + + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry(itr, &eda->cache, list_node) { + if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) { + *eda_entry = *itr; + result = 0; + goto out_unlock; + } + } + /* Not found */ +out_unlock: + spin_unlock_irqrestore(&eda->lock, flags); + return result; +} + +/* + * Execute function for every element in the cache + * + * @function: function to execute on element of cache (must be atomic) + * @priv: private data of function + * @returns: result of first function that failed, or last function + * executed if no function failed. + * + * Stop executing when function returns error for any element in cache. + * + * IMPORTANT: We are using a spinlock here: the function executed on each + * element has to be atomic. + */ +int wlp_eda_for_each(struct wlp_eda *eda, wlp_eda_for_each_f function, + void *priv) +{ + int result = 0; + struct wlp *wlp = container_of(eda, struct wlp, eda); + struct wlp_eda_node *entry; + unsigned long flags; + + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry(entry, &eda->cache, list_node) { + result = (*function)(wlp, entry, priv); + if (result < 0) + break; + } + spin_unlock_irqrestore(&eda->lock, flags); + return result; +} + +/* + * Execute function for single element in the cache (return dev addr) + * + * @virt_addr: index into EDA cache used to determine which element to + * execute the function on + * @dev_addr: device address of element in cache will be returned using + * @dev_addr + * @function: function to execute on element of cache (must be atomic) + * @priv: private data of function + * @returns: result of function + * + * IMPORTANT: We are using a spinlock here: the function executed on the + * element has to be atomic. + */ +int wlp_eda_for_virtual(struct wlp_eda *eda, + const unsigned char virt_addr[ETH_ALEN], + struct uwb_dev_addr *dev_addr, + wlp_eda_for_each_f function, + void *priv) +{ + int result = 0; + struct wlp *wlp = container_of(eda, struct wlp, eda); + struct device *dev = &wlp->rc->uwb_dev.dev; + struct wlp_eda_node *itr; + unsigned long flags; + int found = 0; + + spin_lock_irqsave(&eda->lock, flags); + list_for_each_entry(itr, &eda->cache, list_node) { + if (!memcmp(itr->virt_addr, virt_addr, + sizeof(itr->virt_addr))) { + d_printf(6, dev, "EDA: looking for " + "%02x:%02x:%02x:%02x:%02x:%02x hit %02x:%02x " + "wss %p tag 0x%02x state %u\n", + virt_addr[0], virt_addr[1], + virt_addr[2], virt_addr[3], + virt_addr[4], virt_addr[5], + itr->dev_addr.data[1], + itr->dev_addr.data[0], itr->wss, + itr->tag, itr->state); + result = (*function)(wlp, itr, priv); + *dev_addr = itr->dev_addr; + found = 1; + break; + } else + d_printf(6, dev, "EDA: looking for " + "%02x:%02x:%02x:%02x:%02x:%02x " + "against " + "%02x:%02x:%02x:%02x:%02x:%02x miss\n", + virt_addr[0], virt_addr[1], + virt_addr[2], virt_addr[3], + virt_addr[4], virt_addr[5], + itr->virt_addr[0], itr->virt_addr[1], + itr->virt_addr[2], itr->virt_addr[3], + itr->virt_addr[4], itr->virt_addr[5]); + } + if (!found) { + if (printk_ratelimit()) + dev_err(dev, "EDA: Eth addr %02x:%02x:%02x" + ":%02x:%02x:%02x not found.\n", + virt_addr[0], virt_addr[1], + virt_addr[2], virt_addr[3], + virt_addr[4], virt_addr[5]); + result = -ENODEV; + } + spin_unlock_irqrestore(&eda->lock, flags); + return result; +} + +static const char *__wlp_wss_connect_state[] = { "WLP_WSS_UNCONNECTED", + "WLP_WSS_CONNECTED", + "WLP_WSS_CONNECT_FAILED", +}; + +static const char *wlp_wss_connect_state_str(unsigned id) +{ + if (id >= ARRAY_SIZE(__wlp_wss_connect_state)) + return "unknown WSS connection state"; + return __wlp_wss_connect_state[id]; +} + +/* + * View EDA cache from user space + * + * A debugging feature to give user visibility into the EDA cache. Also + * used to display members of WSS to user (called from wlp_wss_members_show()) + */ +ssize_t wlp_eda_show(struct wlp *wlp, char *buf) +{ + ssize_t result = 0; + struct wlp_eda_node *entry; + unsigned long flags; + struct wlp_eda *eda = &wlp->eda; + spin_lock_irqsave(&eda->lock, flags); + result = scnprintf(buf, PAGE_SIZE, "#eth_addr dev_addr wss_ptr " + "tag state virt_addr\n"); + list_for_each_entry(entry, &eda->cache, list_node) { + result += scnprintf(buf + result, PAGE_SIZE - result, + "%02x:%02x:%02x:%02x:%02x:%02x %02x:%02x " + "%p 0x%02x %s " + "%02x:%02x:%02x:%02x:%02x:%02x\n", + entry->eth_addr[0], entry->eth_addr[1], + entry->eth_addr[2], entry->eth_addr[3], + entry->eth_addr[4], entry->eth_addr[5], + entry->dev_addr.data[1], + entry->dev_addr.data[0], entry->wss, + entry->tag, + wlp_wss_connect_state_str(entry->state), + entry->virt_addr[0], entry->virt_addr[1], + entry->virt_addr[2], entry->virt_addr[3], + entry->virt_addr[4], entry->virt_addr[5]); + if (result >= PAGE_SIZE) + break; + } + spin_unlock_irqrestore(&eda->lock, flags); + return result; +} +EXPORT_SYMBOL_GPL(wlp_eda_show); + +/* + * Add new EDA cache entry based on user input in sysfs + * + * Should only be used for debugging. + * + * The WSS is assumed to be the only WSS supported. This needs to be + * redesigned when we support more than one WSS. + */ +ssize_t wlp_eda_store(struct wlp *wlp, const char *buf, size_t size) +{ + ssize_t result; + struct wlp_eda *eda = &wlp->eda; + u8 eth_addr[6]; + struct uwb_dev_addr dev_addr; + u8 tag; + unsigned state; + + result = sscanf(buf, "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx " + "%02hhx:%02hhx %02hhx %u\n", + ð_addr[0], ð_addr[1], + ð_addr[2], ð_addr[3], + ð_addr[4], ð_addr[5], + &dev_addr.data[1], &dev_addr.data[0], &tag, &state); + switch (result) { + case 6: /* no dev addr specified -- remove entry NOT IMPLEMENTED */ + /*result = wlp_eda_rm(eda, eth_addr, &dev_addr);*/ + result = -ENOSYS; + break; + case 10: + state = state >= 1 ? 1 : 0; + result = wlp_eda_create_node(eda, eth_addr, &dev_addr); + if (result < 0 && result != -EEXIST) + goto error; + /* Set virtual addr to be same as MAC */ + result = wlp_eda_update_node(eda, &dev_addr, &wlp->wss, + eth_addr, tag, state); + if (result < 0) + goto error; + break; + default: /* bad format */ + result = -EINVAL; + } +error: + return result < 0 ? result : size; +} +EXPORT_SYMBOL_GPL(wlp_eda_store); |