iwlwifi: extend notification wait

Sometimes, for example when we ask the uCode
for calibration, we wait for the "complete"
response while we also need the results that
are sent in other, interim, notifications.

Currently we handle this by installing an RX
handler globally, but that isn't needed as
this is the only time we want to use these
notifications.

So in order to be able to simplify at least
future code that does the same, extend the
notification wait framework to allow you to
wait for multiple commands and decide based
on the command whether the wait finished.

While at it, also fix a race that can then
become relevant -- if the wait function has
returned true once it shouldn't be called
again, today this can happen due to races
between the triggering and the wakeup.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c b/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
index 2e1a31797a9e59c16af11c7630e2b576f236b11e..6d6bef329bee61c7a9d21fafec263a24812bd35a 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
@@ -59,9 +59,12 @@ static int iwlagn_disable_pan(struct iwl_priv *priv,
        __le32 old_filter = send->filter_flags;
        u8 old_dev_type = send->dev_type;
        int ret;
+       static const u8 deactivate_cmd[] = {
+               REPLY_WIPAN_DEACTIVATION_COMPLETE
+       };
 
        iwl_init_notification_wait(&priv->notif_wait, &disable_wait,
-                                  REPLY_WIPAN_DEACTIVATION_COMPLETE,
+                                  deactivate_cmd, ARRAY_SIZE(deactivate_cmd),
                                   NULL, NULL);
 
        send->filter_flags &= ~RXON_FILTER_ASSOC_MSK;

diff --git a/drivers/net/wireless/iwlwifi/iwl-notif-wait.c b/drivers/net/wireless/iwlwifi/iwl-notif-wait.c
index 88dc4a0f96b45657c032d9f6cd5071d70b720a4e..0066b899fe5cffe39ae526b73987e75026632ec5 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-notif-wait.c
+++ b/drivers/net/wireless/iwlwifi/iwl-notif-wait.c
@@ -75,21 +75,45 @@ void iwl_notification_wait_init(struct iwl_notif_wait_data *notif_wait)
 void iwl_notification_wait_notify(struct iwl_notif_wait_data *notif_wait,
                                  struct iwl_rx_packet *pkt)
 {
+       bool triggered = false;
+
        if (!list_empty(&notif_wait->notif_waits)) {
                struct iwl_notification_wait *w;
 
                spin_lock(&notif_wait->notif_wait_lock);
                list_for_each_entry(w, &notif_wait->notif_waits, list) {
-                       if (w->cmd != pkt->hdr.cmd)
+                       int i;
+                       bool found = false;
+
+                       /*
+                        * If it already finished (triggered) or has been
+                        * aborted then don't evaluate it again to avoid races,
+                        * Otherwise the function could be called again even
+                        * though it returned true before
+                        */
+                       if (w->triggered || w->aborted)
+                               continue;
+
+                       for (i = 0; i < w->n_cmds; i++) {
+                               if (w->cmds[i] == pkt->hdr.cmd) {
+                                       found = true;
+                                       break;
+                               }
+                       }
+                       if (!found)
                                continue;
-                       w->triggered = true;
-                       if (w->fn)
-                               w->fn(notif_wait, pkt, w->fn_data);
+
+                       if (!w->fn || w->fn(notif_wait, pkt, w->fn_data)) {
+                               w->triggered = true;
+                               triggered = true;
+                       }
                }
                spin_unlock(&notif_wait->notif_wait_lock);
 
-               wake_up_all(&notif_wait->notif_waitq);
        }
+
+       if (triggered)
+               wake_up_all(&notif_wait->notif_waitq);
 }
 
 void iwl_abort_notification_waits(struct iwl_notif_wait_data *notif_wait)
@@ -109,14 +133,18 @@ void iwl_abort_notification_waits(struct iwl_notif_wait_data *notif_wait)
 void
 iwl_init_notification_wait(struct iwl_notif_wait_data *notif_wait,
                           struct iwl_notification_wait *wait_entry,
-                          u8 cmd,
-                          void (*fn)(struct iwl_notif_wait_data *notif_wait,
+                          const u8 *cmds, int n_cmds,
+                          bool (*fn)(struct iwl_notif_wait_data *notif_wait,
                                      struct iwl_rx_packet *pkt, void *data),
                           void *fn_data)
 {
+       if (WARN_ON(n_cmds > MAX_NOTIF_CMDS))
+               n_cmds = MAX_NOTIF_CMDS;
+
        wait_entry->fn = fn;
        wait_entry->fn_data = fn_data;
-       wait_entry->cmd = cmd;
+       wait_entry->n_cmds = n_cmds;
+       memcpy(wait_entry->cmds, cmds, n_cmds);
        wait_entry->triggered = false;
        wait_entry->aborted = false;
 

diff --git a/drivers/net/wireless/iwlwifi/iwl-notif-wait.h b/drivers/net/wireless/iwlwifi/iwl-notif-wait.h
index 5e8af957aa7bf730586dcc235b779df904df7913..821523100cf1e615e227acfeeb37f22dd59a5fa2 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-notif-wait.h
+++ b/drivers/net/wireless/iwlwifi/iwl-notif-wait.h
@@ -72,11 +72,19 @@ struct iwl_notif_wait_data {
        wait_queue_head_t notif_waitq;
 };
 
+#define MAX_NOTIF_CMDS 5
+
 /**
  * struct iwl_notification_wait - notification wait entry
  * @list: list head for global list
- * @fn: function called with the notification
- * @cmd: command ID
+ * @fn: Function called with the notification. If the function
+ *     returns true, the wait is over, if it returns false then
+ *     the waiter stays blocked. If no function is given, any
+ *     of the listed commands will unblock the waiter.
+ * @cmds: command IDs
+ * @n_cmds: number of command IDs
+ * @triggered: waiter should be woken up
+ * @aborted: wait was aborted
  *
  * This structure is not used directly, to wait for a
  * notification declare it on the stack, and call
@@ -93,11 +101,12 @@ struct iwl_notif_wait_data {
 struct iwl_notification_wait {
        struct list_head list;
 
-       void (*fn)(struct iwl_notif_wait_data *notif_data,
+       bool (*fn)(struct iwl_notif_wait_data *notif_data,
                   struct iwl_rx_packet *pkt, void *data);
        void *fn_data;
 
-       u8 cmd;
+       u8 cmds[MAX_NOTIF_CMDS];
+       u8 n_cmds;
        bool triggered, aborted;
 };
 
@@ -112,8 +121,8 @@ void iwl_abort_notification_waits(struct iwl_notif_wait_data *notif_data);
 void __acquires(wait_entry)
 iwl_init_notification_wait(struct iwl_notif_wait_data *notif_data,
                           struct iwl_notification_wait *wait_entry,
-                          u8 cmd,
-                          void (*fn)(struct iwl_notif_wait_data *notif_data,
+                          const u8 *cmds, int n_cmds,
+                          bool (*fn)(struct iwl_notif_wait_data *notif_data,
                                      struct iwl_rx_packet *pkt, void *data),
                           void *fn_data);
 

diff --git a/drivers/net/wireless/iwlwifi/iwl-testmode.c b/drivers/net/wireless/iwlwifi/iwl-testmode.c
index 76f7f925143614c351c45bfc0e590809dcc4e638..645b8500d02fbbc18eaf7f25565e981a5748032a 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-testmode.c
+++ b/drivers/net/wireless/iwlwifi/iwl-testmode.c
@@ -420,10 +420,13 @@ nla_put_failure:
 static int iwl_testmode_cfg_init_calib(struct iwl_priv *priv)
 {
        struct iwl_notification_wait calib_wait;
+       static const u8 calib_complete[] = {
+               CALIBRATION_COMPLETE_NOTIFICATION
+       };
        int ret;
 
        iwl_init_notification_wait(&priv->notif_wait, &calib_wait,
-                                  CALIBRATION_COMPLETE_NOTIFICATION,
+                                  calib_complete, ARRAY_SIZE(calib_complete),
                                   NULL, NULL);
        ret = iwl_init_alive_start(priv);
        if (ret) {

diff --git a/drivers/net/wireless/iwlwifi/iwl-ucode.c b/drivers/net/wireless/iwlwifi/iwl-ucode.c
index 2528287288372b0137c44b5abded3c6ce92b47e4..44b0e72ca7fbdcc67fc3e56fb2ee2c9b3ec49175 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-ucode.c
+++ b/drivers/net/wireless/iwlwifi/iwl-ucode.c
@@ -417,9 +417,8 @@ struct iwl_alive_data {
        u8 subtype;
 };
 
-static void iwl_alive_fn(struct iwl_notif_wait_data *notif_wait,
-                           struct iwl_rx_packet *pkt,
-                           void *data)
+static bool iwl_alive_fn(struct iwl_notif_wait_data *notif_wait,
+                        struct iwl_rx_packet *pkt, void *data)
 {
        struct iwl_priv *priv =
                container_of(notif_wait, struct iwl_priv, notif_wait);
@@ -440,6 +439,8 @@ static void iwl_alive_fn(struct iwl_notif_wait_data *notif_wait,
 
        alive_data->subtype = palive->ver_subtype;
        alive_data->valid = palive->is_valid == UCODE_VALID_OK;
+
+       return true;
 }
 
 #define UCODE_ALIVE_TIMEOUT    HZ
@@ -453,6 +454,7 @@ int iwl_load_ucode_wait_alive(struct iwl_priv *priv,
        const struct fw_img *fw;
        int ret;
        enum iwl_ucode_type old_type;
+       static const u8 alive_cmd[] = { REPLY_ALIVE };
 
        old_type = priv->shrd->ucode_type;
        priv->shrd->ucode_type = ucode_type;
@@ -463,8 +465,9 @@ int iwl_load_ucode_wait_alive(struct iwl_priv *priv,
        if (!fw)
                return -EINVAL;
 
-       iwl_init_notification_wait(&priv->notif_wait, &alive_wait, REPLY_ALIVE,
-                                     iwl_alive_fn, &alive_data);
+       iwl_init_notification_wait(&priv->notif_wait, &alive_wait,
+                                  alive_cmd, ARRAY_SIZE(alive_cmd),
+                                  iwl_alive_fn, &alive_data);
 
        ret = iwl_trans_start_fw(trans(priv), fw);
        if (ret) {
@@ -522,6 +525,9 @@ int iwl_load_ucode_wait_alive(struct iwl_priv *priv,
 int iwl_run_init_ucode(struct iwl_priv *priv)
 {
        struct iwl_notification_wait calib_wait;
+       static const u8 calib_complete[] = {
+               CALIBRATION_COMPLETE_NOTIFICATION
+       };
        int ret;
 
        lockdep_assert_held(&priv->mutex);
@@ -534,8 +540,8 @@ int iwl_run_init_ucode(struct iwl_priv *priv)
                return 0;
 
        iwl_init_notification_wait(&priv->notif_wait, &calib_wait,
-                                     CALIBRATION_COMPLETE_NOTIFICATION,
-                                     NULL, NULL);
+                                  calib_complete, ARRAY_SIZE(calib_complete),
+                                  NULL, NULL);
 
        /* Will also start the device */
        ret = iwl_load_ucode_wait_alive(priv, IWL_UCODE_INIT);