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Diffstat (limited to 'drivers/uwb/wlp/eda.c')
-rw-r--r--drivers/uwb/wlp/eda.c449
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 0000000..cdfe8df
--- /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);
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