net: qca_spi: Fix race condition in spi transfers
With performance optimization the spi transfer and messages of basic
register operations like qcaspi_read_register moved into the private
driver structure. But they weren't protected against mutual access
(e.g. between driver kthread and ethtool). So dumping the QCA7000
registers via ethtool during network traffic could make spi_sync
hang forever, because the completion in spi_message is overwritten.
So revert the optimization completely.
Fixes: 291ab06ecf676 ("net: qualcomm: new Ethernet over SPI driver for QCA700")
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/qualcomm/qca_7k.c b/drivers/net/ethernet/qualcomm/qca_7k.c
index ffe7a16..6c8543f 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k.c
+++ b/drivers/net/ethernet/qualcomm/qca_7k.c
@@ -45,34 +45,33 @@
{
__be16 rx_data;
__be16 tx_data;
- struct spi_transfer *transfer;
- struct spi_message *msg;
+ struct spi_transfer transfer[2];
+ struct spi_message msg;
int ret;
+ memset(transfer, 0, sizeof(transfer));
+
+ spi_message_init(&msg);
+
tx_data = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_INTERNAL | reg);
+ *result = 0;
+
+ transfer[0].tx_buf = &tx_data;
+ transfer[0].len = QCASPI_CMD_LEN;
+ transfer[1].rx_buf = &rx_data;
+ transfer[1].len = QCASPI_CMD_LEN;
+
+ spi_message_add_tail(&transfer[0], &msg);
if (qca->legacy_mode) {
- msg = &qca->spi_msg1;
- transfer = &qca->spi_xfer1;
- transfer->tx_buf = &tx_data;
- transfer->rx_buf = NULL;
- transfer->len = QCASPI_CMD_LEN;
- spi_sync(qca->spi_dev, msg);
- } else {
- msg = &qca->spi_msg2;
- transfer = &qca->spi_xfer2[0];
- transfer->tx_buf = &tx_data;
- transfer->rx_buf = NULL;
- transfer->len = QCASPI_CMD_LEN;
- transfer = &qca->spi_xfer2[1];
+ spi_sync(qca->spi_dev, &msg);
+ spi_message_init(&msg);
}
- transfer->tx_buf = NULL;
- transfer->rx_buf = &rx_data;
- transfer->len = QCASPI_CMD_LEN;
- ret = spi_sync(qca->spi_dev, msg);
+ spi_message_add_tail(&transfer[1], &msg);
+ ret = spi_sync(qca->spi_dev, &msg);
if (!ret)
- ret = msg->status;
+ ret = msg.status;
if (ret)
qcaspi_spi_error(qca);
@@ -86,35 +85,32 @@
qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value)
{
__be16 tx_data[2];
- struct spi_transfer *transfer;
- struct spi_message *msg;
+ struct spi_transfer transfer[2];
+ struct spi_message msg;
int ret;
+ memset(&transfer, 0, sizeof(transfer));
+
+ spi_message_init(&msg);
+
tx_data[0] = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_INTERNAL | reg);
tx_data[1] = cpu_to_be16(value);
+ transfer[0].tx_buf = &tx_data[0];
+ transfer[0].len = QCASPI_CMD_LEN;
+ transfer[1].tx_buf = &tx_data[1];
+ transfer[1].len = QCASPI_CMD_LEN;
+
+ spi_message_add_tail(&transfer[0], &msg);
if (qca->legacy_mode) {
- msg = &qca->spi_msg1;
- transfer = &qca->spi_xfer1;
- transfer->tx_buf = &tx_data[0];
- transfer->rx_buf = NULL;
- transfer->len = QCASPI_CMD_LEN;
- spi_sync(qca->spi_dev, msg);
- } else {
- msg = &qca->spi_msg2;
- transfer = &qca->spi_xfer2[0];
- transfer->tx_buf = &tx_data[0];
- transfer->rx_buf = NULL;
- transfer->len = QCASPI_CMD_LEN;
- transfer = &qca->spi_xfer2[1];
+ spi_sync(qca->spi_dev, &msg);
+ spi_message_init(&msg);
}
- transfer->tx_buf = &tx_data[1];
- transfer->rx_buf = NULL;
- transfer->len = QCASPI_CMD_LEN;
- ret = spi_sync(qca->spi_dev, msg);
+ spi_message_add_tail(&transfer[1], &msg);
+ ret = spi_sync(qca->spi_dev, &msg);
if (!ret)
- ret = msg->status;
+ ret = msg.status;
if (ret)
qcaspi_spi_error(qca);
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index 206f026..66b775d 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -99,22 +99,24 @@
qcaspi_write_burst(struct qcaspi *qca, u8 *src, u32 len)
{
__be16 cmd;
- struct spi_message *msg = &qca->spi_msg2;
- struct spi_transfer *transfer = &qca->spi_xfer2[0];
+ struct spi_message msg;
+ struct spi_transfer transfer[2];
int ret;
+ memset(&transfer, 0, sizeof(transfer));
+ spi_message_init(&msg);
+
cmd = cpu_to_be16(QCA7K_SPI_WRITE | QCA7K_SPI_EXTERNAL);
- transfer->tx_buf = &cmd;
- transfer->rx_buf = NULL;
- transfer->len = QCASPI_CMD_LEN;
- transfer = &qca->spi_xfer2[1];
- transfer->tx_buf = src;
- transfer->rx_buf = NULL;
- transfer->len = len;
+ transfer[0].tx_buf = &cmd;
+ transfer[0].len = QCASPI_CMD_LEN;
+ transfer[1].tx_buf = src;
+ transfer[1].len = len;
- ret = spi_sync(qca->spi_dev, msg);
+ spi_message_add_tail(&transfer[0], &msg);
+ spi_message_add_tail(&transfer[1], &msg);
+ ret = spi_sync(qca->spi_dev, &msg);
- if (ret || (msg->actual_length != QCASPI_CMD_LEN + len)) {
+ if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) {
qcaspi_spi_error(qca);
return 0;
}
@@ -125,17 +127,20 @@
static u32
qcaspi_write_legacy(struct qcaspi *qca, u8 *src, u32 len)
{
- struct spi_message *msg = &qca->spi_msg1;
- struct spi_transfer *transfer = &qca->spi_xfer1;
+ struct spi_message msg;
+ struct spi_transfer transfer;
int ret;
- transfer->tx_buf = src;
- transfer->rx_buf = NULL;
- transfer->len = len;
+ memset(&transfer, 0, sizeof(transfer));
+ spi_message_init(&msg);
- ret = spi_sync(qca->spi_dev, msg);
+ transfer.tx_buf = src;
+ transfer.len = len;
- if (ret || (msg->actual_length != len)) {
+ spi_message_add_tail(&transfer, &msg);
+ ret = spi_sync(qca->spi_dev, &msg);
+
+ if (ret || (msg.actual_length != len)) {
qcaspi_spi_error(qca);
return 0;
}
@@ -146,23 +151,25 @@
static u32
qcaspi_read_burst(struct qcaspi *qca, u8 *dst, u32 len)
{
- struct spi_message *msg = &qca->spi_msg2;
+ struct spi_message msg;
__be16 cmd;
- struct spi_transfer *transfer = &qca->spi_xfer2[0];
+ struct spi_transfer transfer[2];
int ret;
+ memset(&transfer, 0, sizeof(transfer));
+ spi_message_init(&msg);
+
cmd = cpu_to_be16(QCA7K_SPI_READ | QCA7K_SPI_EXTERNAL);
- transfer->tx_buf = &cmd;
- transfer->rx_buf = NULL;
- transfer->len = QCASPI_CMD_LEN;
- transfer = &qca->spi_xfer2[1];
- transfer->tx_buf = NULL;
- transfer->rx_buf = dst;
- transfer->len = len;
+ transfer[0].tx_buf = &cmd;
+ transfer[0].len = QCASPI_CMD_LEN;
+ transfer[1].rx_buf = dst;
+ transfer[1].len = len;
- ret = spi_sync(qca->spi_dev, msg);
+ spi_message_add_tail(&transfer[0], &msg);
+ spi_message_add_tail(&transfer[1], &msg);
+ ret = spi_sync(qca->spi_dev, &msg);
- if (ret || (msg->actual_length != QCASPI_CMD_LEN + len)) {
+ if (ret || (msg.actual_length != QCASPI_CMD_LEN + len)) {
qcaspi_spi_error(qca);
return 0;
}
@@ -173,17 +180,20 @@
static u32
qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len)
{
- struct spi_message *msg = &qca->spi_msg1;
- struct spi_transfer *transfer = &qca->spi_xfer1;
+ struct spi_message msg;
+ struct spi_transfer transfer;
int ret;
- transfer->tx_buf = NULL;
- transfer->rx_buf = dst;
- transfer->len = len;
+ memset(&transfer, 0, sizeof(transfer));
+ spi_message_init(&msg);
- ret = spi_sync(qca->spi_dev, msg);
+ transfer.rx_buf = dst;
+ transfer.len = len;
- if (ret || (msg->actual_length != len)) {
+ spi_message_add_tail(&transfer, &msg);
+ ret = spi_sync(qca->spi_dev, &msg);
+
+ if (ret || (msg.actual_length != len)) {
qcaspi_spi_error(qca);
return 0;
}
@@ -195,19 +205,23 @@
qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd)
{
__be16 tx_data;
- struct spi_message *msg = &qca->spi_msg1;
- struct spi_transfer *transfer = &qca->spi_xfer1;
+ struct spi_message msg;
+ struct spi_transfer transfer;
int ret;
- tx_data = cpu_to_be16(cmd);
- transfer->len = sizeof(tx_data);
- transfer->tx_buf = &tx_data;
- transfer->rx_buf = NULL;
+ memset(&transfer, 0, sizeof(transfer));
- ret = spi_sync(qca->spi_dev, msg);
+ spi_message_init(&msg);
+
+ tx_data = cpu_to_be16(cmd);
+ transfer.len = sizeof(cmd);
+ transfer.tx_buf = &tx_data;
+ spi_message_add_tail(&transfer, &msg);
+
+ ret = spi_sync(qca->spi_dev, &msg);
if (!ret)
- ret = msg->status;
+ ret = msg.status;
if (ret)
qcaspi_spi_error(qca);
@@ -835,16 +849,6 @@
qca = netdev_priv(dev);
memset(qca, 0, sizeof(struct qcaspi));
- memset(&qca->spi_xfer1, 0, sizeof(struct spi_transfer));
- memset(&qca->spi_xfer2, 0, sizeof(struct spi_transfer) * 2);
-
- spi_message_init(&qca->spi_msg1);
- spi_message_add_tail(&qca->spi_xfer1, &qca->spi_msg1);
-
- spi_message_init(&qca->spi_msg2);
- spi_message_add_tail(&qca->spi_xfer2[0], &qca->spi_msg2);
- spi_message_add_tail(&qca->spi_xfer2[1], &qca->spi_msg2);
-
memset(&qca->txr, 0, sizeof(qca->txr));
qca->txr.count = TX_RING_MAX_LEN;
}
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.h b/drivers/net/ethernet/qualcomm/qca_spi.h
index fc4beb1..fc0e987 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.h
+++ b/drivers/net/ethernet/qualcomm/qca_spi.h
@@ -83,11 +83,6 @@
struct tx_ring txr;
struct qcaspi_stats stats;
- struct spi_message spi_msg1;
- struct spi_message spi_msg2;
- struct spi_transfer spi_xfer1;
- struct spi_transfer spi_xfer2[2];
-
u8 *rx_buffer;
u32 buffer_size;
u8 sync;