iwlagn: check DMA mapping errors

DMA mappings can fail, but the current code
doesn't check for that. Add checking, which
requires some restructuring for proper error
paths.

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

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-tx.c b/drivers/net/wireless/iwlwifi/iwl-tx.c
index 5a7cd177fe5e..e69597ea43e2 100644
--- a/drivers/net/wireless/iwlwifi/iwl-tx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-tx.c
@@ -500,7 +500,6 @@ int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
         }
 
         memset(out_meta, 0, sizeof(*out_meta)); /* re-initialize to NULL */
-        out_meta->flags = cmd->flags | CMD_MAPPED;
         if (cmd->flags & CMD_WANT_SKB)
                 out_meta->source = cmd;
         if (cmd->flags & CMD_ASYNC)
@@ -538,13 +537,20 @@ int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
                                 q->write_ptr, idx, priv->cmd_queue);
         }
 #endif
-        txq->need_update = 1;
-
         phys_addr = pci_map_single(priv->pci_dev, &out_cmd->hdr,
                                    fix_size, PCI_DMA_BIDIRECTIONAL);
+        if (unlikely(pci_dma_mapping_error(priv->pci_dev, phys_addr))) {
+                idx = -ENOMEM;
+                goto out;
+        }
+
         dma_unmap_addr_set(out_meta, mapping, phys_addr);
         dma_unmap_len_set(out_meta, len, fix_size);
 
+        out_meta->flags = cmd->flags | CMD_MAPPED;
+
+        txq->need_update = 1;
+
         trace_iwlwifi_dev_hcmd(priv, &out_cmd->hdr, fix_size, cmd->flags);
 
         priv->cfg->ops->lib->txq_attach_buf_to_tfd(priv, txq,
@@ -555,6 +561,7 @@ int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
         q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd);
         iwl_txq_update_write_ptr(priv, txq);
 
+ out:
         spin_unlock_irqrestore(&priv->hcmd_lock, flags);
         return idx;
 }