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",
+                        &eth_addr[0], &eth_addr[1],
+                        &eth_addr[2], &eth_addr[3],
+                        &eth_addr[4], &eth_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);