From dd48744964296b5713032ea1d66eb9e3d990e287 Mon Sep 17 00:00:00 2001 From: Zhu Yi Date: Mon, 22 Mar 2010 02:28:41 -0700 Subject: [PATCH] iwlwifi: fix DMA allocation warnings Below warning is triggered sometimes at module removal time when CONFIG_DMA_API_DEBUG is enabled. This should be caused by we didn't unmap pending commands (enqueued, but no complete notification received) for the Tx command queue. [ 1583.107469] ------------[ cut here ]------------ [ 1583.107539] WARNING: at lib/dma-debug.c:688 dma_debug_device_change+0x13c/0x180() [ 1583.107617] Hardware name: ... [ 1583.107664] pci 0000:04:00.0: DMA-API: device driver has pending DMA allocations while released from device [count=1] [ 1583.107713] Modules linked in: ... [ 1583.111661] Pid: 16970, comm: modprobe Tainted: G W 2.6.34-rc1-wl #33 [ 1583.111727] Call Trace: [ 1583.111779] [] ? dma_debug_device_change+0x13c/0x180 [ 1583.111833] [] ? dma_debug_device_change+0x13c/0x180 [ 1583.111908] [] warn_slowpath_common+0x71/0xd0 [ 1583.111963] [] ? dma_debug_device_change+0x13c/0x180 [ 1583.112016] [] warn_slowpath_fmt+0x2b/0x30 [ 1583.112086] [] dma_debug_device_change+0x13c/0x180 [ 1583.112142] [] notifier_call_chain+0x53/0x90 [ 1583.112198] [] ? down_read+0x6e/0x90 [ 1583.112271] [] __blocking_notifier_call_chain+0x49/0x70 [ 1583.112326] [] blocking_notifier_call_chain+0x1f/0x30 [ 1583.112380] [] __device_release_driver+0x8c/0xa0 [ 1583.112451] [] driver_detach+0x8f/0xa0 [ 1583.112538] [] bus_remove_driver+0x82/0x100 [ 1583.112595] [] driver_unregister+0x49/0x80 [ 1583.112671] [] ? sysfs_remove_file+0x12/0x20 [ 1583.112727] [] pci_unregister_driver+0x32/0x80 [ 1583.112791] [] iwl_exit+0x12/0x19 [iwlagn] [ 1583.112848] [] sys_delete_module+0x15a/0x210 [ 1583.112870] [] ? up_read+0x1b/0x30 [ 1583.112893] [] ? trace_hardirqs_off_thunk+0xc/0x10 [ 1583.112924] [] ? trace_hardirqs_on_thunk+0xc/0x10 [ 1583.112947] [] ? do_page_fault+0x1ff/0x3c0 [ 1583.112978] [] ? restore_all_notrace+0x0/0x18 [ 1583.113002] [] ? trace_hardirqs_on_caller+0x20/0x190 [ 1583.113025] [] sysenter_do_call+0x12/0x38 [ 1583.113054] ---[ end trace fc23e059cc4c2ced ]--- Signed-off-by: Zhu Yi Signed-off-by: Reinette Chatre --- drivers/net/wireless/iwlwifi/iwl-tx.c | 48 ++++++++++++++++++++++++++++++++--- 1 file changed, 45 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-tx.c b/drivers/net/wireless/iwlwifi/iwl-tx.c index 8c12311..6aa3090 100644 --- a/drivers/net/wireless/iwlwifi/iwl-tx.c +++ b/drivers/net/wireless/iwlwifi/iwl-tx.c @@ -193,10 +193,34 @@ void iwl_cmd_queue_free(struct iwl_priv *priv) struct iwl_queue *q = &txq->q; struct device *dev = &priv->pci_dev->dev; int i; + bool huge = false; if (q->n_bd == 0) return; + for (; q->read_ptr != q->write_ptr; + q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) { + /* we have no way to tell if it is a huge cmd ATM */ + i = get_cmd_index(q, q->read_ptr, 0); + + if (txq->meta[i].flags & CMD_SIZE_HUGE) { + huge = true; + continue; + } + + pci_unmap_single(priv->pci_dev, + pci_unmap_addr(&txq->meta[i], mapping), + pci_unmap_len(&txq->meta[i], len), + PCI_DMA_BIDIRECTIONAL); + } + if (huge) { + i = q->n_window; + pci_unmap_single(priv->pci_dev, + pci_unmap_addr(&txq->meta[i], mapping), + pci_unmap_len(&txq->meta[i], len), + PCI_DMA_BIDIRECTIONAL); + } + /* De-alloc array of command/tx buffers */ for (i = 0; i <= TFD_CMD_SLOTS; i++) kfree(txq->cmd[i]); @@ -1049,6 +1073,14 @@ int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd) spin_lock_irqsave(&priv->hcmd_lock, flags); + /* If this is a huge cmd, mark the huge flag also on the meta.flags + * of the _original_ cmd. This is used for DMA mapping clean up. + */ + if (cmd->flags & CMD_SIZE_HUGE) { + idx = get_cmd_index(q, q->write_ptr, 0); + txq->meta[idx].flags = CMD_SIZE_HUGE; + } + idx = get_cmd_index(q, q->write_ptr, cmd->flags & CMD_SIZE_HUGE); out_cmd = txq->cmd[idx]; out_meta = &txq->meta[idx]; @@ -1226,6 +1258,7 @@ void iwl_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) bool huge = !!(pkt->hdr.sequence & SEQ_HUGE_FRAME); struct iwl_device_cmd *cmd; struct iwl_cmd_meta *meta; + struct iwl_tx_queue *txq = &priv->txq[IWL_CMD_QUEUE_NUM]; /* If a Tx command is being handled and it isn't in the actual * command queue then there a command routing bug has been introduced @@ -1239,9 +1272,17 @@ void iwl_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) return; } - cmd_index = get_cmd_index(&priv->txq[IWL_CMD_QUEUE_NUM].q, index, huge); - cmd = priv->txq[IWL_CMD_QUEUE_NUM].cmd[cmd_index]; - meta = &priv->txq[IWL_CMD_QUEUE_NUM].meta[cmd_index]; + /* If this is a huge cmd, clear the huge flag on the meta.flags + * of the _original_ cmd. So that iwl_cmd_queue_free won't unmap + * the DMA buffer for the scan (huge) command. + */ + if (huge) { + cmd_index = get_cmd_index(&txq->q, index, 0); + txq->meta[cmd_index].flags = 0; + } + cmd_index = get_cmd_index(&txq->q, index, huge); + cmd = txq->cmd[cmd_index]; + meta = &txq->meta[cmd_index]; pci_unmap_single(priv->pci_dev, pci_unmap_addr(meta, mapping), @@ -1263,6 +1304,7 @@ void iwl_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb) get_cmd_string(cmd->hdr.cmd)); wake_up_interruptible(&priv->wait_command_queue); } + meta->flags = 0; } EXPORT_SYMBOL(iwl_tx_cmd_complete); -- 2.7.4