kernel_optimize_test/drivers/net/wireless/iwlegacy/iwl-tx.c
Stanislaw Gruszka 81e63263aa iwlegacy: fix enqueue hcmd race conditions
We mark command as huge by using meta->flags from other (non huge) command,
but flags can be possibly overridden, when non huge command is enqueued,
what can lead to:

WARNING: at lib/dma-debug.c:696 dma_debug_device_change+0x1a3/0x1f0()
DMA-API: device driver has pending DMA allocations while released from device [count=1]

To fix introduce additional CMD_MAPPED to mark command as mapped and
serialize iwl_enqueue_hcmd() with iwl_tx_cmd_complete() using
hcmd_lock. Serialization will also fix possible race conditions,
because q->read_ptr, q->write_ptr are modified/used in parallel.

Do not change callback, I did (and fixed) that mistake in iwlagn.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-04-29 15:36:14 -04:00

657 lines
19 KiB
C

/******************************************************************************
*
* Copyright(c) 2003 - 2011 Intel Corporation. All rights reserved.
*
* Portions of this file are derived from the ipw3945 project, as well
* as portions of the ieee80211 subsystem header files.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License 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, USA
*
* The full GNU General Public License is included in this distribution in the
* file called LICENSE.
*
* Contact Information:
* Intel Linux Wireless <ilw@linux.intel.com>
* Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
*
*****************************************************************************/
#include <linux/etherdevice.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <net/mac80211.h>
#include "iwl-eeprom.h"
#include "iwl-dev.h"
#include "iwl-core.h"
#include "iwl-sta.h"
#include "iwl-io.h"
#include "iwl-helpers.h"
/**
* iwl_legacy_txq_update_write_ptr - Send new write index to hardware
*/
void
iwl_legacy_txq_update_write_ptr(struct iwl_priv *priv, struct iwl_tx_queue *txq)
{
u32 reg = 0;
int txq_id = txq->q.id;
if (txq->need_update == 0)
return;
/* if we're trying to save power */
if (test_bit(STATUS_POWER_PMI, &priv->status)) {
/* wake up nic if it's powered down ...
* uCode will wake up, and interrupt us again, so next
* time we'll skip this part. */
reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
IWL_DEBUG_INFO(priv,
"Tx queue %d requesting wakeup,"
" GP1 = 0x%x\n", txq_id, reg);
iwl_legacy_set_bit(priv, CSR_GP_CNTRL,
CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
return;
}
iwl_legacy_write_direct32(priv, HBUS_TARG_WRPTR,
txq->q.write_ptr | (txq_id << 8));
/*
* else not in power-save mode,
* uCode will never sleep when we're
* trying to tx (during RFKILL, we're not trying to tx).
*/
} else
iwl_write32(priv, HBUS_TARG_WRPTR,
txq->q.write_ptr | (txq_id << 8));
txq->need_update = 0;
}
EXPORT_SYMBOL(iwl_legacy_txq_update_write_ptr);
/**
* iwl_legacy_tx_queue_unmap - Unmap any remaining DMA mappings and free skb's
*/
void iwl_legacy_tx_queue_unmap(struct iwl_priv *priv, int txq_id)
{
struct iwl_tx_queue *txq = &priv->txq[txq_id];
struct iwl_queue *q = &txq->q;
if (q->n_bd == 0)
return;
while (q->write_ptr != q->read_ptr) {
priv->cfg->ops->lib->txq_free_tfd(priv, txq);
q->read_ptr = iwl_legacy_queue_inc_wrap(q->read_ptr, q->n_bd);
}
}
EXPORT_SYMBOL(iwl_legacy_tx_queue_unmap);
/**
* iwl_legacy_tx_queue_free - Deallocate DMA queue.
* @txq: Transmit queue to deallocate.
*
* Empty queue by removing and destroying all BD's.
* Free all buffers.
* 0-fill, but do not free "txq" descriptor structure.
*/
void iwl_legacy_tx_queue_free(struct iwl_priv *priv, int txq_id)
{
struct iwl_tx_queue *txq = &priv->txq[txq_id];
struct device *dev = &priv->pci_dev->dev;
int i;
iwl_legacy_tx_queue_unmap(priv, txq_id);
/* De-alloc array of command/tx buffers */
for (i = 0; i < TFD_TX_CMD_SLOTS; i++)
kfree(txq->cmd[i]);
/* De-alloc circular buffer of TFDs */
if (txq->q.n_bd)
dma_free_coherent(dev, priv->hw_params.tfd_size *
txq->q.n_bd, txq->tfds, txq->q.dma_addr);
/* De-alloc array of per-TFD driver data */
kfree(txq->txb);
txq->txb = NULL;
/* deallocate arrays */
kfree(txq->cmd);
kfree(txq->meta);
txq->cmd = NULL;
txq->meta = NULL;
/* 0-fill queue descriptor structure */
memset(txq, 0, sizeof(*txq));
}
EXPORT_SYMBOL(iwl_legacy_tx_queue_free);
/**
* iwl_cmd_queue_unmap - Unmap any remaining DMA mappings from command queue
*/
void iwl_legacy_cmd_queue_unmap(struct iwl_priv *priv)
{
struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
struct iwl_queue *q = &txq->q;
int i;
if (q->n_bd == 0)
return;
while (q->read_ptr != q->write_ptr) {
i = iwl_legacy_get_cmd_index(q, q->read_ptr, 0);
if (txq->meta[i].flags & CMD_MAPPED) {
pci_unmap_single(priv->pci_dev,
dma_unmap_addr(&txq->meta[i], mapping),
dma_unmap_len(&txq->meta[i], len),
PCI_DMA_BIDIRECTIONAL);
txq->meta[i].flags = 0;
}
q->read_ptr = iwl_legacy_queue_inc_wrap(q->read_ptr, q->n_bd);
}
i = q->n_window;
if (txq->meta[i].flags & CMD_MAPPED) {
pci_unmap_single(priv->pci_dev,
dma_unmap_addr(&txq->meta[i], mapping),
dma_unmap_len(&txq->meta[i], len),
PCI_DMA_BIDIRECTIONAL);
txq->meta[i].flags = 0;
}
}
EXPORT_SYMBOL(iwl_legacy_cmd_queue_unmap);
/**
* iwl_legacy_cmd_queue_free - Deallocate DMA queue.
* @txq: Transmit queue to deallocate.
*
* Empty queue by removing and destroying all BD's.
* Free all buffers.
* 0-fill, but do not free "txq" descriptor structure.
*/
void iwl_legacy_cmd_queue_free(struct iwl_priv *priv)
{
struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
struct device *dev = &priv->pci_dev->dev;
int i;
iwl_legacy_cmd_queue_unmap(priv);
/* De-alloc array of command/tx buffers */
for (i = 0; i <= TFD_CMD_SLOTS; i++)
kfree(txq->cmd[i]);
/* De-alloc circular buffer of TFDs */
if (txq->q.n_bd)
dma_free_coherent(dev, priv->hw_params.tfd_size * txq->q.n_bd,
txq->tfds, txq->q.dma_addr);
/* deallocate arrays */
kfree(txq->cmd);
kfree(txq->meta);
txq->cmd = NULL;
txq->meta = NULL;
/* 0-fill queue descriptor structure */
memset(txq, 0, sizeof(*txq));
}
EXPORT_SYMBOL(iwl_legacy_cmd_queue_free);
/*************** DMA-QUEUE-GENERAL-FUNCTIONS *****
* DMA services
*
* Theory of operation
*
* A Tx or Rx queue resides in host DRAM, and is comprised of a circular buffer
* of buffer descriptors, each of which points to one or more data buffers for
* the device to read from or fill. Driver and device exchange status of each
* queue via "read" and "write" pointers. Driver keeps minimum of 2 empty
* entries in each circular buffer, to protect against confusing empty and full
* queue states.
*
* The device reads or writes the data in the queues via the device's several
* DMA/FIFO channels. Each queue is mapped to a single DMA channel.
*
* For Tx queue, there are low mark and high mark limits. If, after queuing
* the packet for Tx, free space become < low mark, Tx queue stopped. When
* reclaiming packets (on 'tx done IRQ), if free space become > high mark,
* Tx queue resumed.
*
* See more detailed info in iwl-4965-hw.h.
***************************************************/
int iwl_legacy_queue_space(const struct iwl_queue *q)
{
int s = q->read_ptr - q->write_ptr;
if (q->read_ptr > q->write_ptr)
s -= q->n_bd;
if (s <= 0)
s += q->n_window;
/* keep some reserve to not confuse empty and full situations */
s -= 2;
if (s < 0)
s = 0;
return s;
}
EXPORT_SYMBOL(iwl_legacy_queue_space);
/**
* iwl_legacy_queue_init - Initialize queue's high/low-water and read/write indexes
*/
static int iwl_legacy_queue_init(struct iwl_priv *priv, struct iwl_queue *q,
int count, int slots_num, u32 id)
{
q->n_bd = count;
q->n_window = slots_num;
q->id = id;
/* count must be power-of-two size, otherwise iwl_legacy_queue_inc_wrap
* and iwl_legacy_queue_dec_wrap are broken. */
BUG_ON(!is_power_of_2(count));
/* slots_num must be power-of-two size, otherwise
* iwl_legacy_get_cmd_index is broken. */
BUG_ON(!is_power_of_2(slots_num));
q->low_mark = q->n_window / 4;
if (q->low_mark < 4)
q->low_mark = 4;
q->high_mark = q->n_window / 8;
if (q->high_mark < 2)
q->high_mark = 2;
q->write_ptr = q->read_ptr = 0;
return 0;
}
/**
* iwl_legacy_tx_queue_alloc - Alloc driver data and TFD CB for one Tx/cmd queue
*/
static int iwl_legacy_tx_queue_alloc(struct iwl_priv *priv,
struct iwl_tx_queue *txq, u32 id)
{
struct device *dev = &priv->pci_dev->dev;
size_t tfd_sz = priv->hw_params.tfd_size * TFD_QUEUE_SIZE_MAX;
/* Driver private data, only for Tx (not command) queues,
* not shared with device. */
if (id != priv->cmd_queue) {
txq->txb = kzalloc(sizeof(txq->txb[0]) *
TFD_QUEUE_SIZE_MAX, GFP_KERNEL);
if (!txq->txb) {
IWL_ERR(priv, "kmalloc for auxiliary BD "
"structures failed\n");
goto error;
}
} else {
txq->txb = NULL;
}
/* Circular buffer of transmit frame descriptors (TFDs),
* shared with device */
txq->tfds = dma_alloc_coherent(dev, tfd_sz, &txq->q.dma_addr,
GFP_KERNEL);
if (!txq->tfds) {
IWL_ERR(priv, "pci_alloc_consistent(%zd) failed\n", tfd_sz);
goto error;
}
txq->q.id = id;
return 0;
error:
kfree(txq->txb);
txq->txb = NULL;
return -ENOMEM;
}
/**
* iwl_legacy_tx_queue_init - Allocate and initialize one tx/cmd queue
*/
int iwl_legacy_tx_queue_init(struct iwl_priv *priv, struct iwl_tx_queue *txq,
int slots_num, u32 txq_id)
{
int i, len;
int ret;
int actual_slots = slots_num;
/*
* Alloc buffer array for commands (Tx or other types of commands).
* For the command queue (#4/#9), allocate command space + one big
* command for scan, since scan command is very huge; the system will
* not have two scans at the same time, so only one is needed.
* For normal Tx queues (all other queues), no super-size command
* space is needed.
*/
if (txq_id == priv->cmd_queue)
actual_slots++;
txq->meta = kzalloc(sizeof(struct iwl_cmd_meta) * actual_slots,
GFP_KERNEL);
txq->cmd = kzalloc(sizeof(struct iwl_device_cmd *) * actual_slots,
GFP_KERNEL);
if (!txq->meta || !txq->cmd)
goto out_free_arrays;
len = sizeof(struct iwl_device_cmd);
for (i = 0; i < actual_slots; i++) {
/* only happens for cmd queue */
if (i == slots_num)
len = IWL_MAX_CMD_SIZE;
txq->cmd[i] = kmalloc(len, GFP_KERNEL);
if (!txq->cmd[i])
goto err;
}
/* Alloc driver data array and TFD circular buffer */
ret = iwl_legacy_tx_queue_alloc(priv, txq, txq_id);
if (ret)
goto err;
txq->need_update = 0;
/*
* For the default queues 0-3, set up the swq_id
* already -- all others need to get one later
* (if they need one at all).
*/
if (txq_id < 4)
iwl_legacy_set_swq_id(txq, txq_id, txq_id);
/* TFD_QUEUE_SIZE_MAX must be power-of-two size, otherwise
* iwl_legacy_queue_inc_wrap and iwl_legacy_queue_dec_wrap are broken. */
BUILD_BUG_ON(TFD_QUEUE_SIZE_MAX & (TFD_QUEUE_SIZE_MAX - 1));
/* Initialize queue's high/low-water marks, and head/tail indexes */
iwl_legacy_queue_init(priv, &txq->q,
TFD_QUEUE_SIZE_MAX, slots_num, txq_id);
/* Tell device where to find queue */
priv->cfg->ops->lib->txq_init(priv, txq);
return 0;
err:
for (i = 0; i < actual_slots; i++)
kfree(txq->cmd[i]);
out_free_arrays:
kfree(txq->meta);
kfree(txq->cmd);
return -ENOMEM;
}
EXPORT_SYMBOL(iwl_legacy_tx_queue_init);
void iwl_legacy_tx_queue_reset(struct iwl_priv *priv, struct iwl_tx_queue *txq,
int slots_num, u32 txq_id)
{
int actual_slots = slots_num;
if (txq_id == priv->cmd_queue)
actual_slots++;
memset(txq->meta, 0, sizeof(struct iwl_cmd_meta) * actual_slots);
txq->need_update = 0;
/* Initialize queue's high/low-water marks, and head/tail indexes */
iwl_legacy_queue_init(priv, &txq->q,
TFD_QUEUE_SIZE_MAX, slots_num, txq_id);
/* Tell device where to find queue */
priv->cfg->ops->lib->txq_init(priv, txq);
}
EXPORT_SYMBOL(iwl_legacy_tx_queue_reset);
/*************** HOST COMMAND QUEUE FUNCTIONS *****/
/**
* iwl_legacy_enqueue_hcmd - enqueue a uCode command
* @priv: device private data point
* @cmd: a point to the ucode command structure
*
* The function returns < 0 values to indicate the operation is
* failed. On success, it turns the index (> 0) of command in the
* command queue.
*/
int iwl_legacy_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
{
struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
struct iwl_queue *q = &txq->q;
struct iwl_device_cmd *out_cmd;
struct iwl_cmd_meta *out_meta;
dma_addr_t phys_addr;
unsigned long flags;
int len;
u32 idx;
u16 fix_size;
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
* 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);
if (iwl_legacy_is_rfkill(priv) || iwl_legacy_is_ctkill(priv)) {
IWL_WARN(priv, "Not sending command - %s KILL\n",
iwl_legacy_is_rfkill(priv) ? "RF" : "CT");
return -EIO;
}
spin_lock_irqsave(&priv->hcmd_lock, flags);
if (iwl_legacy_queue_space(q) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {
spin_unlock_irqrestore(&priv->hcmd_lock, flags);
IWL_ERR(priv, "Restarting adapter due to command queue full\n");
queue_work(priv->workqueue, &priv->restart);
return -ENOSPC;
}
idx = iwl_legacy_get_cmd_index(q, q->write_ptr, cmd->flags & CMD_SIZE_HUGE);
out_cmd = txq->cmd[idx];
out_meta = &txq->meta[idx];
if (WARN_ON(out_meta->flags & CMD_MAPPED)) {
spin_unlock_irqrestore(&priv->hcmd_lock, flags);
return -ENOSPC;
}
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)
out_meta->callback = cmd->callback;
out_cmd->hdr.cmd = cmd->id;
memcpy(&out_cmd->cmd.payload, cmd->data, cmd->len);
/* At this point, the out_cmd now has all of the incoming cmd
* information */
out_cmd->hdr.flags = 0;
out_cmd->hdr.sequence = cpu_to_le16(QUEUE_TO_SEQ(priv->cmd_queue) |
INDEX_TO_SEQ(q->write_ptr));
if (cmd->flags & CMD_SIZE_HUGE)
out_cmd->hdr.sequence |= SEQ_HUGE_FRAME;
len = sizeof(struct iwl_device_cmd);
if (idx == TFD_CMD_SLOTS)
len = IWL_MAX_CMD_SIZE;
#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
switch (out_cmd->hdr.cmd) {
case REPLY_TX_LINK_QUALITY_CMD:
case SENSITIVITY_CMD:
IWL_DEBUG_HC_DUMP(priv,
"Sending command %s (#%x), seq: 0x%04X, "
"%d bytes at %d[%d]:%d\n",
iwl_legacy_get_cmd_string(out_cmd->hdr.cmd),
out_cmd->hdr.cmd,
le16_to_cpu(out_cmd->hdr.sequence), fix_size,
q->write_ptr, idx, priv->cmd_queue);
break;
default:
IWL_DEBUG_HC(priv, "Sending command %s (#%x), seq: 0x%04X, "
"%d bytes at %d[%d]:%d\n",
iwl_legacy_get_cmd_string(out_cmd->hdr.cmd),
out_cmd->hdr.cmd,
le16_to_cpu(out_cmd->hdr.sequence), fix_size,
q->write_ptr, idx, priv->cmd_queue);
}
#endif
txq->need_update = 1;
if (priv->cfg->ops->lib->txq_update_byte_cnt_tbl)
/* Set up entry in queue's byte count circular buffer */
priv->cfg->ops->lib->txq_update_byte_cnt_tbl(priv, txq, 0);
phys_addr = pci_map_single(priv->pci_dev, &out_cmd->hdr,
fix_size, PCI_DMA_BIDIRECTIONAL);
dma_unmap_addr_set(out_meta, mapping, phys_addr);
dma_unmap_len_set(out_meta, len, fix_size);
trace_iwlwifi_legacy_dev_hcmd(priv, &out_cmd->hdr,
fix_size, cmd->flags);
priv->cfg->ops->lib->txq_attach_buf_to_tfd(priv, txq,
phys_addr, fix_size, 1,
U32_PAD(cmd->len));
/* Increment and update queue's write index */
q->write_ptr = iwl_legacy_queue_inc_wrap(q->write_ptr, q->n_bd);
iwl_legacy_txq_update_write_ptr(priv, txq);
spin_unlock_irqrestore(&priv->hcmd_lock, flags);
return idx;
}
/**
* iwl_legacy_hcmd_queue_reclaim - Reclaim TX command queue entries already Tx'd
*
* When FW advances 'R' index, all entries between old and new 'R' index
* need to be reclaimed. As result, some free space forms. If there is
* enough free space (> low mark), wake the stack that feeds us.
*/
static void iwl_legacy_hcmd_queue_reclaim(struct iwl_priv *priv, int txq_id,
int idx, int cmd_idx)
{
struct iwl_tx_queue *txq = &priv->txq[txq_id];
struct iwl_queue *q = &txq->q;
int nfreed = 0;
if ((idx >= q->n_bd) || (iwl_legacy_queue_used(q, idx) == 0)) {
IWL_ERR(priv, "Read index for DMA queue txq id (%d), index %d, "
"is out of range [0-%d] %d %d.\n", txq_id,
idx, q->n_bd, q->write_ptr, q->read_ptr);
return;
}
for (idx = iwl_legacy_queue_inc_wrap(idx, q->n_bd); q->read_ptr != idx;
q->read_ptr = iwl_legacy_queue_inc_wrap(q->read_ptr, q->n_bd)) {
if (nfreed++ > 0) {
IWL_ERR(priv, "HCMD skipped: index (%d) %d %d\n", idx,
q->write_ptr, q->read_ptr);
queue_work(priv->workqueue, &priv->restart);
}
}
}
/**
* iwl_legacy_tx_cmd_complete - Pull unused buffers off the queue and reclaim them
* @rxb: Rx buffer to reclaim
*
* If an Rx buffer has an async callback associated with it the callback
* will be executed. The attached skb (if present) will only be freed
* if the callback returns 1
*/
void
iwl_legacy_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb)
{
struct iwl_rx_packet *pkt = rxb_addr(rxb);
u16 sequence = le16_to_cpu(pkt->hdr.sequence);
int txq_id = SEQ_TO_QUEUE(sequence);
int index = SEQ_TO_INDEX(sequence);
int cmd_index;
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[priv->cmd_queue];
unsigned long flags;
/* 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
* in the queue management code. */
if (WARN(txq_id != priv->cmd_queue,
"wrong command queue %d (should be %d), sequence 0x%X readp=%d writep=%d\n",
txq_id, priv->cmd_queue, sequence,
priv->txq[priv->cmd_queue].q.read_ptr,
priv->txq[priv->cmd_queue].q.write_ptr)) {
iwl_print_hex_error(priv, pkt, 32);
return;
}
cmd_index = iwl_legacy_get_cmd_index(&txq->q, index, huge);
cmd = txq->cmd[cmd_index];
meta = &txq->meta[cmd_index];
pci_unmap_single(priv->pci_dev,
dma_unmap_addr(meta, mapping),
dma_unmap_len(meta, len),
PCI_DMA_BIDIRECTIONAL);
/* Input error checking is done when commands are added to queue. */
if (meta->flags & CMD_WANT_SKB) {
meta->source->reply_page = (unsigned long)rxb_addr(rxb);
rxb->page = NULL;
} else if (meta->callback)
meta->callback(priv, cmd, pkt);
spin_lock_irqsave(&priv->hcmd_lock, flags);
iwl_legacy_hcmd_queue_reclaim(priv, txq_id, index, cmd_index);
if (!(meta->flags & CMD_ASYNC)) {
clear_bit(STATUS_HCMD_ACTIVE, &priv->status);
IWL_DEBUG_INFO(priv, "Clearing HCMD_ACTIVE for command %s\n",
iwl_legacy_get_cmd_string(cmd->hdr.cmd));
wake_up_interruptible(&priv->wait_command_queue);
}
/* Mark as unmapped */
meta->flags = 0;
spin_unlock_irqrestore(&priv->hcmd_lock, flags);
}
EXPORT_SYMBOL(iwl_legacy_tx_cmd_complete);