w1: hold bus_mutex in netlink and search
The bus_mutex needs to be taken to serialize access to a specific bus. netlink wasn't updated when bus_mutex was added and was calling without that lock held, and not all of the masters were holding the bus_mutex in a search. This was causing the ds2490 hardware to stop responding when both netlink and /sys slaves were executing bus commands at the same time. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
b3be177a19
commit
d3a8a9dbb9
|
@ -326,13 +326,14 @@ static void ds1wm_search(void *data, struct w1_master *master_dev,
|
|||
unsigned slaves_found = 0;
|
||||
unsigned int pass = 0;
|
||||
|
||||
mutex_lock(&master_dev->bus_mutex);
|
||||
dev_dbg(&ds1wm_data->pdev->dev, "search begin\n");
|
||||
while (true) {
|
||||
++pass;
|
||||
if (pass > 100) {
|
||||
dev_dbg(&ds1wm_data->pdev->dev,
|
||||
"too many attempts (100), search aborted\n");
|
||||
return;
|
||||
break;
|
||||
}
|
||||
|
||||
mutex_lock(&master_dev->bus_mutex);
|
||||
|
@ -439,6 +440,7 @@ static void ds1wm_search(void *data, struct w1_master *master_dev,
|
|||
dev_dbg(&ds1wm_data->pdev->dev,
|
||||
"pass: %d total: %d search done ms d bit pos: %d\n", pass,
|
||||
slaves_found, ms_discrep_bit);
|
||||
mutex_unlock(&master_dev->bus_mutex);
|
||||
}
|
||||
|
||||
/* --------------------------------------------------------------------- */
|
||||
|
|
|
@ -727,9 +727,11 @@ static void ds9490r_search(void *data, struct w1_master *master,
|
|||
*/
|
||||
u64 buf[2*64/8];
|
||||
|
||||
mutex_lock(&master->bus_mutex);
|
||||
|
||||
/* address to start searching at */
|
||||
if (ds_send_data(dev, (u8 *)&master->search_id, 8) < 0)
|
||||
return;
|
||||
goto search_out;
|
||||
master->search_id = 0;
|
||||
|
||||
value = COMM_SEARCH_ACCESS | COMM_IM | COMM_RST | COMM_SM | COMM_F |
|
||||
|
@ -739,7 +741,7 @@ static void ds9490r_search(void *data, struct w1_master *master,
|
|||
search_limit = 0;
|
||||
index = search_type | (search_limit << 8);
|
||||
if (ds_send_control(dev, value, index) < 0)
|
||||
return;
|
||||
goto search_out;
|
||||
|
||||
do {
|
||||
schedule_timeout(jtime);
|
||||
|
@ -791,6 +793,8 @@ static void ds9490r_search(void *data, struct w1_master *master,
|
|||
master->max_slave_count);
|
||||
set_bit(W1_WARN_MAX_COUNT, &master->flags);
|
||||
}
|
||||
search_out:
|
||||
mutex_unlock(&master->bus_mutex);
|
||||
}
|
||||
|
||||
#if 0
|
||||
|
|
|
@ -246,11 +246,16 @@ static int w1_process_command_master(struct w1_master *dev,
|
|||
{
|
||||
int err = -EINVAL;
|
||||
|
||||
/* drop bus_mutex for search (does it's own locking), and add/remove
|
||||
* which doesn't use the bus
|
||||
*/
|
||||
switch (req_cmd->cmd) {
|
||||
case W1_CMD_SEARCH:
|
||||
case W1_CMD_ALARM_SEARCH:
|
||||
case W1_CMD_LIST_SLAVES:
|
||||
mutex_unlock(&dev->bus_mutex);
|
||||
err = w1_get_slaves(dev, req_msg, req_hdr, req_cmd);
|
||||
mutex_lock(&dev->bus_mutex);
|
||||
break;
|
||||
case W1_CMD_READ:
|
||||
case W1_CMD_WRITE:
|
||||
|
@ -262,8 +267,12 @@ static int w1_process_command_master(struct w1_master *dev,
|
|||
break;
|
||||
case W1_CMD_SLAVE_ADD:
|
||||
case W1_CMD_SLAVE_REMOVE:
|
||||
mutex_unlock(&dev->bus_mutex);
|
||||
mutex_lock(&dev->mutex);
|
||||
err = w1_process_command_addremove(dev, req_msg, req_hdr,
|
||||
req_cmd);
|
||||
mutex_unlock(&dev->mutex);
|
||||
mutex_lock(&dev->bus_mutex);
|
||||
break;
|
||||
default:
|
||||
err = -EINVAL;
|
||||
|
@ -400,7 +409,7 @@ static void w1_process_cb(struct w1_master *dev, struct w1_async_cmd *async_cmd)
|
|||
struct w1_slave *sl = node->sl;
|
||||
struct w1_netlink_cmd *cmd = NULL;
|
||||
|
||||
mutex_lock(&dev->mutex);
|
||||
mutex_lock(&dev->bus_mutex);
|
||||
dev->portid = node->block->portid;
|
||||
if (sl && w1_reset_select_slave(sl))
|
||||
err = -ENODEV;
|
||||
|
@ -437,7 +446,7 @@ static void w1_process_cb(struct w1_master *dev, struct w1_async_cmd *async_cmd)
|
|||
else
|
||||
atomic_dec(&dev->refcnt);
|
||||
dev->portid = 0;
|
||||
mutex_unlock(&dev->mutex);
|
||||
mutex_unlock(&dev->bus_mutex);
|
||||
|
||||
mutex_lock(&dev->list_mutex);
|
||||
list_del(&async_cmd->async_entry);
|
||||
|
|
Loading…
Reference in New Issue
Block a user