4.18-stable review patch. If anyone has any objections, please let me know.
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From: Golan Ben Ami golan.ben.ami@intel.com
[ Upstream commit f5955a6cc3862a02d46f50b723c3172d24d749a5 ]
Nowadays, the tfd queue max size is 2^8, and the reserved size in the command header sequence field for the tfd entry index is 8 bits, allowing an injective function from the hw pointers to the tfd entry index in the sequence field.
In 22560 devices the tfd queue max size is 2^16, meaning that the hw pointers are 16 bit long (allowing to point to each entry in the tfd queue). However, the reserved space in the sequence field for the tfd entry doesn't change, and we are limited to 8 bit. This requires cancelling the injective function from hw pointer to tfd entry in the sequence number.
Use iwl_pcie_get_cmd_index to wrap the hw pointer's to the n_window size, which is maximum 256 in tx queues, and so, keep the injective function between the window wrapped hw pointers to tfd entry index in the sequence.
Signed-off-by: Golan Ben Ami golan.ben.ami@intel.com Signed-off-by: Luca Coelho luciano.coelho@intel.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wireless/intel/iwlwifi/pcie/internal.h | 12 ++++++++---- drivers/net/wireless/intel/iwlwifi/pcie/tx.c | 11 ++++++++--- 2 files changed, 16 insertions(+), 7 deletions(-)
--- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h +++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h @@ -660,7 +660,7 @@ static inline void iwl_enable_fw_load_in } }
-static inline u8 iwl_pcie_get_cmd_index(struct iwl_txq *q, u32 index) +static inline u8 iwl_pcie_get_cmd_index(const struct iwl_txq *q, u32 index) { return index & (q->n_window - 1); } @@ -730,9 +730,13 @@ static inline void iwl_stop_queue(struct
static inline bool iwl_queue_used(const struct iwl_txq *q, int i) { - return q->write_ptr >= q->read_ptr ? - (i >= q->read_ptr && i < q->write_ptr) : - !(i < q->read_ptr && i >= q->write_ptr); + int index = iwl_pcie_get_cmd_index(q, i); + int r = iwl_pcie_get_cmd_index(q, q->read_ptr); + int w = iwl_pcie_get_cmd_index(q, q->write_ptr); + + return w >= r ? + (index >= r && index < w) : + !(index < r && index >= w); }
static inline bool iwl_is_rfkill_set(struct iwl_trans *trans) --- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c @@ -1225,9 +1225,13 @@ static void iwl_pcie_cmdq_reclaim(struct struct iwl_txq *txq = trans_pcie->txq[txq_id]; unsigned long flags; int nfreed = 0; + u16 r;
lockdep_assert_held(&txq->lock);
+ idx = iwl_pcie_get_cmd_index(txq, idx); + r = iwl_pcie_get_cmd_index(txq, txq->read_ptr); + if ((idx >= TFD_QUEUE_SIZE_MAX) || (!iwl_queue_used(txq, idx))) { IWL_ERR(trans, "%s: Read index for DMA queue txq id (%d), index %d is out of range [0-%d] %d %d.\n", @@ -1236,12 +1240,13 @@ static void iwl_pcie_cmdq_reclaim(struct return; }
- for (idx = iwl_queue_inc_wrap(idx); txq->read_ptr != idx; - txq->read_ptr = iwl_queue_inc_wrap(txq->read_ptr)) { + for (idx = iwl_queue_inc_wrap(idx); r != idx; + r = iwl_queue_inc_wrap(r)) { + txq->read_ptr = iwl_queue_inc_wrap(txq->read_ptr);
if (nfreed++ > 0) { IWL_ERR(trans, "HCMD skipped: index (%d) %d %d\n", - idx, txq->write_ptr, txq->read_ptr); + idx, txq->write_ptr, r); iwl_force_nmi(trans); } }