NFC: protect nci_data_exchange transactions

Protect 'cb' and 'cb_context' arguments in nci_data_exchange.
In fact, this implements a queue with max length of 1 data
exchange transactions in parallel.

Signed-off-by: Ilan Elias <ilane@ti.com>
Acked-by: Lauro Ramos Venancio <lauro.venancio@openbossa.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Ilan Elias 2011-09-22 11:36:19 +03:00 committed by John W. Linville
parent de054799b7
commit 38f04c6b1b
4 changed files with 13 additions and 2 deletions

View File

@ -40,6 +40,7 @@ enum {
NCI_UP, NCI_UP,
NCI_DISCOVERY, NCI_DISCOVERY,
NCI_POLL_ACTIVE, NCI_POLL_ACTIVE,
NCI_DATA_EXCHANGE,
}; };
/* NCI timeouts */ /* NCI timeouts */

View File

@ -453,6 +453,7 @@ static int nci_data_exchange(struct nfc_dev *nfc_dev, __u32 target_idx,
void *cb_context) void *cb_context)
{ {
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev); struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
int rc;
nfc_dbg("entry, target_idx %d, len %d", target_idx, skb->len); nfc_dbg("entry, target_idx %d, len %d", target_idx, skb->len);
@ -461,11 +462,18 @@ static int nci_data_exchange(struct nfc_dev *nfc_dev, __u32 target_idx,
return -EINVAL; return -EINVAL;
} }
if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
return -EBUSY;
/* store cb and context to be used on receiving data */ /* store cb and context to be used on receiving data */
ndev->data_exchange_cb = cb; ndev->data_exchange_cb = cb;
ndev->data_exchange_cb_context = cb_context; ndev->data_exchange_cb_context = cb_context;
return nci_send_data(ndev, ndev->conn_id, skb); rc = nci_send_data(ndev, ndev->conn_id, skb);
if (rc)
clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
return rc;
} }
static struct nfc_ops nci_nfc_ops = { static struct nfc_ops nci_nfc_ops = {

View File

@ -54,6 +54,8 @@ void nci_data_exchange_complete(struct nci_dev *ndev,
/* no waiting callback, free skb */ /* no waiting callback, free skb */
kfree_skb(skb); kfree_skb(skb);
} }
clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
} }
/* ----------------- NCI TX Data ----------------- */ /* ----------------- NCI TX Data ----------------- */

View File

@ -215,7 +215,7 @@ static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev,
} }
/* complete the data exchange transaction, if exists */ /* complete the data exchange transaction, if exists */
if (ndev->data_exchange_cb) if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
nci_data_exchange_complete(ndev, NULL, -EIO); nci_data_exchange_complete(ndev, NULL, -EIO);
} }