From f4feb8ac6e666d2ca37cf722166bbfadf2c6adf8 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 19 Oct 2012 14:24:43 +0200 Subject: [PATCH] iwlwifi: support host command with copied data In addition to the NOCOPY flag, add a DUP flag that tells the transport to kmemdup() the buffer and free it after the command completes. Currently this is only supported for a single buffer in a given command, but that could be extended if it should be needed. Reviewed-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- drivers/net/wireless/iwlwifi/iwl-trans.h | 6 ++- drivers/net/wireless/iwlwifi/pcie/internal.h | 2 + drivers/net/wireless/iwlwifi/pcie/rx.c | 3 ++ drivers/net/wireless/iwlwifi/pcie/trans.c | 1 + drivers/net/wireless/iwlwifi/pcie/tx.c | 57 ++++++++++++++++---- 5 files changed, 59 insertions(+), 10 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-trans.h b/drivers/net/wireless/iwlwifi/iwl-trans.h index f75ea6d73ff..76c52378f8f 100644 --- a/drivers/net/wireless/iwlwifi/iwl-trans.h +++ b/drivers/net/wireless/iwlwifi/iwl-trans.h @@ -221,14 +221,18 @@ struct iwl_device_cmd { /** * struct iwl_hcmd_dataflag - flag for each one of the chunks of the command * - * IWL_HCMD_DFL_NOCOPY: By default, the command is copied to the host command's + * @IWL_HCMD_DFL_NOCOPY: By default, the command is copied to the host command's * ring. The transport layer doesn't map the command's buffer to DMA, but * rather copies it to an previously allocated DMA buffer. This flag tells * the transport layer not to copy the command, but to map the existing * buffer. This can save memcpy and is worth with very big comamnds. + * @IWL_HCMD_DFL_DUP: Only valid without NOCOPY, duplicate the memory for this + * chunk internally and free it again after the command completes. This + * can (currently) be used only once per command. */ enum iwl_hcmd_dataflag { IWL_HCMD_DFL_NOCOPY = BIT(0), + IWL_HCMD_DFL_DUP = BIT(1), }; /** diff --git a/drivers/net/wireless/iwlwifi/pcie/internal.h b/drivers/net/wireless/iwlwifi/pcie/internal.h index 6ce58f03bc5..ae0f87e0e58 100644 --- a/drivers/net/wireless/iwlwifi/pcie/internal.h +++ b/drivers/net/wireless/iwlwifi/pcie/internal.h @@ -186,6 +186,8 @@ struct iwl_pcie_tx_queue_entry { struct iwl_device_cmd *cmd; struct iwl_device_cmd *copy_cmd; struct sk_buff *skb; + /* buffer to free after command completes */ + const void *free_buf; struct iwl_cmd_meta meta; }; diff --git a/drivers/net/wireless/iwlwifi/pcie/rx.c b/drivers/net/wireless/iwlwifi/pcie/rx.c index 137af4c46a6..3f03f6e322c 100644 --- a/drivers/net/wireless/iwlwifi/pcie/rx.c +++ b/drivers/net/wireless/iwlwifi/pcie/rx.c @@ -452,6 +452,9 @@ static void iwl_rx_handle_rxbuf(struct iwl_trans *trans, /* The original command isn't needed any more */ kfree(txq->entries[cmd_index].copy_cmd); txq->entries[cmd_index].copy_cmd = NULL; + /* nor is the duplicated part of the command */ + kfree(txq->entries[cmd_index].free_buf); + txq->entries[cmd_index].free_buf = NULL; } /* diff --git a/drivers/net/wireless/iwlwifi/pcie/trans.c b/drivers/net/wireless/iwlwifi/pcie/trans.c index a6a518116c7..b8a155af12c 100644 --- a/drivers/net/wireless/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/iwlwifi/pcie/trans.c @@ -496,6 +496,7 @@ static void iwl_tx_queue_free(struct iwl_trans *trans, int txq_id) for (i = 0; i < txq->q.n_window; i++) { kfree(txq->entries[i].cmd); kfree(txq->entries[i].copy_cmd); + kfree(txq->entries[i].free_buf); } /* De-alloc circular buffer of TFDs */ diff --git a/drivers/net/wireless/iwlwifi/pcie/tx.c b/drivers/net/wireless/iwlwifi/pcie/tx.c index 5db03145186..9cb30ae5e9a 100644 --- a/drivers/net/wireless/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/iwlwifi/pcie/tx.c @@ -517,8 +517,9 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) struct iwl_queue *q = &txq->q; struct iwl_device_cmd *out_cmd; struct iwl_cmd_meta *out_meta; + void *dup_buf = NULL; dma_addr_t phys_addr; - u32 idx; + int idx; u16 copy_size, cmd_size; bool had_nocopy = false; int i; @@ -535,10 +536,33 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) continue; if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY) { had_nocopy = true; + if (WARN_ON(cmd->dataflags[i] & IWL_HCMD_DFL_DUP)) { + idx = -EINVAL; + goto free_dup_buf; + } + } else if (cmd->dataflags[i] & IWL_HCMD_DFL_DUP) { + /* + * This is also a chunk that isn't copied + * to the static buffer so set had_nocopy. + */ + had_nocopy = true; + + /* only allowed once */ + if (WARN_ON(dup_buf)) { + idx = -EINVAL; + goto free_dup_buf; + } + + dup_buf = kmemdup(cmd->data[i], cmd->len[i], + GFP_ATOMIC); + if (!dup_buf) + return -ENOMEM; } else { /* NOCOPY must not be followed by normal! */ - if (WARN_ON(had_nocopy)) - return -EINVAL; + if (WARN_ON(had_nocopy)) { + idx = -EINVAL; + goto free_dup_buf; + } copy_size += cmd->len[i]; } cmd_size += cmd->len[i]; @@ -553,8 +577,10 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) if (WARN(copy_size > TFD_MAX_PAYLOAD_SIZE, "Command %s (%#x) is too large (%d bytes)\n", trans_pcie_get_cmd_string(trans_pcie, cmd->id), - cmd->id, copy_size)) - return -EINVAL; + cmd->id, copy_size)) { + idx = -EINVAL; + goto free_dup_buf; + } spin_lock_bh(&txq->lock); @@ -563,7 +589,8 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) IWL_ERR(trans, "No space in command queue\n"); iwl_op_mode_cmd_queue_full(trans->op_mode); - return -ENOSPC; + idx = -ENOSPC; + goto free_dup_buf; } idx = get_cmd_index(q, q->write_ptr); @@ -587,7 +614,8 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) for (i = 0; i < IWL_MAX_CMD_TFDS; i++) { if (!cmd->len[i]) continue; - if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY) + if (cmd->dataflags[i] & (IWL_HCMD_DFL_NOCOPY | + IWL_HCMD_DFL_DUP)) break; memcpy((u8 *)out_cmd + cmd_pos, cmd->data[i], cmd->len[i]); cmd_pos += cmd->len[i]; @@ -629,11 +657,16 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) iwlagn_txq_attach_buf_to_tfd(trans, txq, phys_addr, copy_size, 1); for (i = 0; i < IWL_MAX_CMD_TFDS; i++) { + const void *data = cmd->data[i]; + if (!cmd->len[i]) continue; - if (!(cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY)) + if (!(cmd->dataflags[i] & (IWL_HCMD_DFL_NOCOPY | + IWL_HCMD_DFL_DUP))) continue; - phys_addr = dma_map_single(trans->dev, (void *)cmd->data[i], + if (cmd->dataflags[i] & IWL_HCMD_DFL_DUP) + data = dup_buf; + phys_addr = dma_map_single(trans->dev, (void *)data, cmd->len[i], DMA_BIDIRECTIONAL); if (dma_mapping_error(trans->dev, phys_addr)) { iwl_unmap_tfd(trans, out_meta, @@ -648,6 +681,9 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) } out_meta->flags = cmd->flags; + if (WARN_ON_ONCE(txq->entries[idx].free_buf)) + kfree(txq->entries[idx].free_buf); + txq->entries[idx].free_buf = dup_buf; txq->need_update = 1; @@ -664,6 +700,9 @@ static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd) out: spin_unlock_bh(&txq->lock); + free_dup_buf: + if (idx < 0) + kfree(dup_buf); return idx; } -- 2.41.0