iwlagn: remove most BUG_ON instances

There are a number of things in the driver that
may result in a BUG(), which is suboptimal since
it's hard to get debugging information out of
the driver in that case and the user experience
is also not good :-)

Almost all BUG_ON instances can be converted to
WARN_ON with a few lines of appropriate error
handling, so do that instead.

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

7 files changed, 42 insertions, 27 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index b4f7510f51ec..0daededb0ff2 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -394,7 +394,9 @@ int iwl_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv,
                 return -EINVAL;
         }
 
-        BUG_ON(addr & ~DMA_BIT_MASK(36));
+        if (WARN_ON(addr & ~DMA_BIT_MASK(36)))
+                return -EINVAL;
+
         if (unlikely(addr & ~IWL_TX_DMA_MASK))
                 IWL_ERR(priv, "Unaligned address = %llx\n",
                           (unsigned long long)addr);
@@ -718,7 +720,10 @@ static void iwl_rx_handle(struct iwl_priv *priv)
                 /* If an RXB doesn't have a Rx queue slot associated with it,
                  * then a bug has been introduced in the queue refilling
                  * routines -- catch it here */
-                BUG_ON(rxb == NULL);
+                if (WARN_ON(rxb == NULL)) {
+                        i = (i + 1) & RX_QUEUE_MASK;
+                        continue;
+                }
 
                 rxq->queue[i] = NULL;
 
diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.c b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
index 859b94a12297..402733638f50 100644
--- a/drivers/net/wireless/iwlwifi/iwl-eeprom.c
+++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.c
@@ -215,12 +215,6 @@ static int iwlcore_get_nvm_type(struct iwl_priv *priv, u32 hw_rev)
         return  nvm_type;
 }
 
-const u8 *iwlcore_eeprom_query_addr(const struct iwl_priv *priv, size_t offset)
-{
-        BUG_ON(offset >= priv->cfg->base_params->eeprom_size);
-        return &priv->eeprom[offset];
-}
-
 static int iwl_init_otp_access(struct iwl_priv *priv)
 {
         int ret;
diff --git a/drivers/net/wireless/iwlwifi/iwl-eeprom.h b/drivers/net/wireless/iwlwifi/iwl-eeprom.h
index 0e9d9703636a..9ce052573c6a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-eeprom.h
+++ b/drivers/net/wireless/iwlwifi/iwl-eeprom.h
@@ -309,7 +309,6 @@ int  iwl_eeprom_check_sku(struct iwl_priv *priv);
 const u8 *iwl_eeprom_query_addr(const struct iwl_priv *priv, size_t offset);
 int iwlcore_eeprom_verify_signature(struct iwl_priv *priv);
 u16 iwl_eeprom_query16(const struct iwl_priv *priv, size_t offset);
-const u8 *iwlcore_eeprom_query_addr(const struct iwl_priv *priv, size_t offset);
 int iwl_init_channel_map(struct iwl_priv *priv);
 void iwl_free_channel_map(struct iwl_priv *priv);
 const struct iwl_channel_info *iwl_get_channel_info(
diff --git a/drivers/net/wireless/iwlwifi/iwl-hcmd.c b/drivers/net/wireless/iwlwifi/iwl-hcmd.c
index 9177b553fe57..8f0beb992ccf 100644
--- a/drivers/net/wireless/iwlwifi/iwl-hcmd.c
+++ b/drivers/net/wireless/iwlwifi/iwl-hcmd.c
@@ -143,10 +143,12 @@ static int iwl_send_cmd_async(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
 {
         int ret;
 
-        BUG_ON(!(cmd->flags & CMD_ASYNC));
+        if (WARN_ON(!(cmd->flags & CMD_ASYNC)))
+                return -EINVAL;
 
         /* An asynchronous command can not expect an SKB to be set. */
-        BUG_ON(cmd->flags & CMD_WANT_SKB);
+        if (WARN_ON(cmd->flags & CMD_WANT_SKB))
+                return -EINVAL;
 
         /* Assign a generic callback if one is not provided */
         if (!cmd->callback)
@@ -169,10 +171,12 @@ int iwl_send_cmd_sync(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
         int cmd_idx;
         int ret;
 
-        lockdep_assert_held(&priv->mutex);
+        if (WARN_ON(cmd->flags & CMD_ASYNC))
+                return -EINVAL;
 
          /* A synchronous command can not have a callback set. */
-        BUG_ON((cmd->flags & CMD_ASYNC) || cmd->callback);
+        if (WARN_ON(cmd->callback))
+                return -EINVAL;
 
         IWL_DEBUG_INFO(priv, "Attempting to send sync command %s\n",
                         get_cmd_string(cmd->id));
diff --git a/drivers/net/wireless/iwlwifi/iwl-power.c b/drivers/net/wireless/iwlwifi/iwl-power.c
index ae176d8da9e8..b7cd95820ff8 100644
--- a/drivers/net/wireless/iwlwifi/iwl-power.c
+++ b/drivers/net/wireless/iwlwifi/iwl-power.c
@@ -188,9 +188,10 @@ static void iwl_static_sleep_cmd(struct iwl_priv *priv,
                         table = range_0;
         }
 
-        BUG_ON(lvl < 0 || lvl >= IWL_POWER_NUM);
-
-        *cmd = table[lvl].cmd;
+        if (WARN_ON(lvl < 0 || lvl >= IWL_POWER_NUM))
+                memset(cmd, 0, sizeof(*cmd));
+        else
+                *cmd = table[lvl].cmd;
 
         if (period == 0) {
                 skip = 0;
diff --git a/drivers/net/wireless/iwlwifi/iwl-sta.c b/drivers/net/wireless/iwlwifi/iwl-sta.c
index c21515640077..3c8cebde16cc 100644
--- a/drivers/net/wireless/iwlwifi/iwl-sta.c
+++ b/drivers/net/wireless/iwlwifi/iwl-sta.c
@@ -494,7 +494,8 @@ int iwl_remove_station(struct iwl_priv *priv, const u8 sta_id,
 
         priv->num_stations--;
 
-        BUG_ON(priv->num_stations < 0);
+        if (WARN_ON(priv->num_stations < 0))
+                priv->num_stations = 0;
 
         spin_unlock_irqrestore(&priv->sta_lock, flags);
 
@@ -679,7 +680,8 @@ void iwl_dealloc_bcast_stations(struct iwl_priv *priv)
 
                 priv->stations[i].used &= ~IWL_STA_UCODE_ACTIVE;
                 priv->num_stations--;
-                BUG_ON(priv->num_stations < 0);
+                if (WARN_ON(priv->num_stations < 0))
+                        priv->num_stations = 0;
                 kfree(priv->stations[i].lq);
                 priv->stations[i].lq = NULL;
         }
@@ -775,7 +777,8 @@ int iwl_send_lq_cmd(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
         spin_unlock_irqrestore(&priv->sta_lock, flags_spin);
 
         iwl_dump_lq_cmd(priv, lq);
-        BUG_ON(init && (cmd.flags & CMD_ASYNC));
+        if (WARN_ON(init && (cmd.flags & CMD_ASYNC)))
+                return -EINVAL;
 
         if (is_lq_table_valid(priv, ctx, lq))
                 ret = iwl_send_cmd(priv, &cmd);
diff --git a/drivers/net/wireless/iwlwifi/iwl-tx.c b/drivers/net/wireless/iwlwifi/iwl-tx.c
index 3732380c4ffe..e7faba57b6e3 100644
--- a/drivers/net/wireless/iwlwifi/iwl-tx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-tx.c
@@ -263,11 +263,13 @@ static int iwl_queue_init(struct iwl_priv *priv, struct iwl_queue *q,
 
         /* count must be power-of-two size, otherwise iwl_queue_inc_wrap
          * and iwl_queue_dec_wrap are broken. */
-        BUG_ON(!is_power_of_2(count));
+        if (WARN_ON(!is_power_of_2(count)))
+                return -EINVAL;
 
         /* slots_num must be power-of-two size, otherwise
          * get_cmd_index is broken. */
-        BUG_ON(!is_power_of_2(slots_num));
+        if (WARN_ON(!is_power_of_2(slots_num)))
+                return -EINVAL;
 
         q->low_mark = q->n_window / 4;
         if (q->low_mark < 4)
@@ -384,7 +386,9 @@ int iwl_tx_queue_init(struct iwl_priv *priv, struct iwl_tx_queue *txq,
         BUILD_BUG_ON(TFD_QUEUE_SIZE_MAX & (TFD_QUEUE_SIZE_MAX - 1));
 
         /* Initialize queue's high/low-water marks, and head/tail indexes */
-        iwl_queue_init(priv, &txq->q, TFD_QUEUE_SIZE_MAX, slots_num, txq_id);
+        ret = iwl_queue_init(priv, &txq->q, TFD_QUEUE_SIZE_MAX, slots_num, txq_id);
+        if (ret)
+                return ret;
 
         /* Tell device where to find queue */
         priv->cfg->ops->lib->txq_init(priv, txq);
@@ -446,14 +450,19 @@ int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
         cmd->len = priv->cfg->ops->utils->get_hcmd_size(cmd->id, cmd->len);
         fix_size = (u16)(cmd->len + sizeof(out_cmd->hdr));
 
-        /* If any of the command structures end up being larger than
+        /*
+         * If any of the command structures end up being larger than
          * the TFD_MAX_PAYLOAD_SIZE, and it sent as a 'small' command then
          * we will need to increase the size of the TFD entries
          * Also, check to see if command buffer should not exceed the size
-         * of device_cmd and max_cmd_size. */
-        BUG_ON((fix_size > TFD_MAX_PAYLOAD_SIZE) &&
-               !(cmd->flags & CMD_SIZE_HUGE));
-        BUG_ON(fix_size > IWL_MAX_CMD_SIZE);
+         * of device_cmd and max_cmd_size.
+         */
+        if (WARN_ON((fix_size > TFD_MAX_PAYLOAD_SIZE) &&
+                    !(cmd->flags & CMD_SIZE_HUGE)))
+                return -EINVAL;
+
+        if (WARN_ON(fix_size > IWL_MAX_CMD_SIZE))
+                return -EINVAL;
 
         if (iwl_is_rfkill(priv) || iwl_is_ctkill(priv)) {
                 IWL_WARN(priv, "Not sending command - %s KILL\n",