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_DISCOVERY,
NCI_POLL_ACTIVE,
NCI_DATA_EXCHANGE,
};
/* NCI timeouts */

View File

@ -453,6 +453,7 @@ static int nci_data_exchange(struct nfc_dev *nfc_dev, __u32 target_idx,
void *cb_context)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
int rc;
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;
}
if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
return -EBUSY;
/* store cb and context to be used on receiving data */
ndev->data_exchange_cb = cb;
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 = {

View File

@ -54,6 +54,8 @@ void nci_data_exchange_complete(struct nci_dev *ndev,
/* no waiting callback, free skb */
kfree_skb(skb);
}
clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
}
/* ----------------- 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 */
if (ndev->data_exchange_cb)
if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
nci_data_exchange_complete(ndev, NULL, -EIO);
}