staging: comedi: Add lockdep_assert_held() calls for dev->mutex

Lots of functions in the core comedi module expect the mutex in `struct
comedi_device` to be held, so add calls to `lockdep_assert_held()` to
check and document that.  An unusual case is the calls to
`lockdep_assert_held()` after successful return from
`comedi_alloc_board_minor()` which allocates a `struct comedi_device`
and returns with its mutex locked.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ian Abbott 2019-04-17 15:39:29 +01:00 committed by Greg Kroah-Hartman
parent f439696c81
commit 77c21b626b
3 changed files with 41 additions and 0 deletions

View File

@ -211,6 +211,8 @@ int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s,
{
struct comedi_async *async = s->async;
lockdep_assert_held(&dev->mutex);
/* Round up new_size to multiple of PAGE_SIZE */
new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK;

View File

@ -164,6 +164,7 @@ static bool comedi_clear_board_dev(struct comedi_device *dev)
unsigned int i = dev->minor;
bool cleared = false;
lockdep_assert_held(&dev->mutex);
mutex_lock(&comedi_board_minor_table_lock);
if (dev == comedi_board_minor_table[i]) {
comedi_board_minor_table[i] = NULL;
@ -260,6 +261,7 @@ comedi_read_subdevice(const struct comedi_device *dev, unsigned int minor)
{
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (minor >= COMEDI_NUM_BOARD_MINORS) {
s = comedi_subdevice_from_minor(dev, minor);
if (!s || (s->subdev_flags & SDF_CMD_READ))
@ -273,6 +275,7 @@ comedi_write_subdevice(const struct comedi_device *dev, unsigned int minor)
{
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (minor >= COMEDI_NUM_BOARD_MINORS) {
s = comedi_subdevice_from_minor(dev, minor);
if (!s || (s->subdev_flags & SDF_CMD_WRITE))
@ -336,6 +339,8 @@ static int resize_async_buffer(struct comedi_device *dev,
struct comedi_async *async = s->async;
int retval;
lockdep_assert_held(&dev->mutex);
if (new_size > async->max_bufsize)
return -EPERM;
@ -726,6 +731,7 @@ static void do_become_nonbusy(struct comedi_device *dev,
{
struct comedi_async *async = s->async;
lockdep_assert_held(&dev->mutex);
comedi_update_subdevice_runflags(s, COMEDI_SRF_RUNNING, 0);
if (async) {
comedi_buf_reset(s);
@ -745,6 +751,7 @@ static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
{
int ret = 0;
lockdep_assert_held(&dev->mutex);
if (comedi_is_subdevice_running(s) && s->cancel)
ret = s->cancel(dev, s);
@ -758,6 +765,7 @@ void comedi_device_cancel_all(struct comedi_device *dev)
struct comedi_subdevice *s;
int i;
lockdep_assert_held(&dev->mutex);
if (!dev->attached)
return;
@ -773,6 +781,7 @@ static int is_device_busy(struct comedi_device *dev)
struct comedi_subdevice *s;
int i;
lockdep_assert_held(&dev->mutex);
if (!dev->attached)
return 0;
@ -805,6 +814,7 @@ static int do_devconfig_ioctl(struct comedi_device *dev,
{
struct comedi_devconfig it;
lockdep_assert_held(&dev->mutex);
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
@ -860,6 +870,7 @@ static int do_bufconfig_ioctl(struct comedi_device *dev,
struct comedi_subdevice *s;
int retval = 0;
lockdep_assert_held(&dev->mutex);
if (copy_from_user(&bc, arg, sizeof(bc)))
return -EFAULT;
@ -920,6 +931,7 @@ static int do_devinfo_ioctl(struct comedi_device *dev,
struct comedi_subdevice *s;
struct comedi_devinfo devinfo;
lockdep_assert_held(&dev->mutex);
memset(&devinfo, 0, sizeof(devinfo));
/* fill devinfo structure */
@ -966,6 +978,7 @@ static int do_subdinfo_ioctl(struct comedi_device *dev,
struct comedi_subdinfo *tmp, *us;
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
tmp = kcalloc(dev->n_subdevices, sizeof(*tmp), GFP_KERNEL);
if (!tmp)
return -ENOMEM;
@ -1039,6 +1052,7 @@ static int do_chaninfo_ioctl(struct comedi_device *dev,
struct comedi_subdevice *s;
struct comedi_chaninfo it;
lockdep_assert_held(&dev->mutex);
if (copy_from_user(&it, arg, sizeof(it)))
return -EFAULT;
@ -1098,6 +1112,7 @@ static int do_bufinfo_ioctl(struct comedi_device *dev,
int retval = 0;
bool become_nonbusy = false;
lockdep_assert_held(&dev->mutex);
if (copy_from_user(&bi, arg, sizeof(bi)))
return -EFAULT;
@ -1282,6 +1297,7 @@ static int check_insn_device_config_length(struct comedi_insn *insn,
*/
static int get_valid_routes(struct comedi_device *dev, unsigned int *data)
{
lockdep_assert_held(&dev->mutex);
data[1] = dev->get_valid_routes(dev, data[1], data + 2);
return 0;
}
@ -1293,6 +1309,7 @@ static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn,
int ret = 0;
int i;
lockdep_assert_held(&dev->mutex);
if (insn->insn & INSN_MASK_SPECIAL) {
/* a non-subdevice instruction */
@ -1513,6 +1530,7 @@ static int do_insnlist_ioctl(struct comedi_device *dev,
int i = 0;
int ret = 0;
lockdep_assert_held(&dev->mutex);
if (copy_from_user(&insnlist, arg, sizeof(insnlist)))
return -EFAULT;
@ -1605,6 +1623,7 @@ static int do_insn_ioctl(struct comedi_device *dev,
unsigned int n_data = MIN_SAMPLES;
int ret = 0;
lockdep_assert_held(&dev->mutex);
if (copy_from_user(&insn, arg, sizeof(insn)))
return -EFAULT;
@ -1655,6 +1674,7 @@ static int __comedi_get_user_cmd(struct comedi_device *dev,
{
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (copy_from_user(cmd, arg, sizeof(*cmd))) {
dev_dbg(dev->class_dev, "bad cmd address\n");
return -EFAULT;
@ -1713,6 +1733,7 @@ static int __comedi_get_user_chanlist(struct comedi_device *dev,
unsigned int *chanlist;
int ret;
lockdep_assert_held(&dev->mutex);
cmd->chanlist = NULL;
chanlist = memdup_user(user_chanlist,
cmd->chanlist_len * sizeof(unsigned int));
@ -1754,6 +1775,8 @@ static int do_cmd_ioctl(struct comedi_device *dev,
unsigned int __user *user_chanlist;
int ret;
lockdep_assert_held(&dev->mutex);
/* get the user's cmd and do some simple validation */
ret = __comedi_get_user_cmd(dev, arg, &cmd);
if (ret)
@ -1861,6 +1884,8 @@ static int do_cmdtest_ioctl(struct comedi_device *dev,
unsigned int __user *user_chanlist;
int ret;
lockdep_assert_held(&dev->mutex);
/* get the user's cmd and do some simple validation */
ret = __comedi_get_user_cmd(dev, arg, &cmd);
if (ret)
@ -1914,6 +1939,7 @@ static int do_lock_ioctl(struct comedi_device *dev, unsigned long arg,
unsigned long flags;
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (arg >= dev->n_subdevices)
return -EINVAL;
s = &dev->subdevices[arg];
@ -1946,6 +1972,7 @@ static int do_unlock_ioctl(struct comedi_device *dev, unsigned long arg,
{
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (arg >= dev->n_subdevices)
return -EINVAL;
s = &dev->subdevices[arg];
@ -1980,6 +2007,7 @@ static int do_cancel_ioctl(struct comedi_device *dev, unsigned long arg,
{
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (arg >= dev->n_subdevices)
return -EINVAL;
s = &dev->subdevices[arg];
@ -2013,6 +2041,7 @@ static int do_poll_ioctl(struct comedi_device *dev, unsigned long arg,
{
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (arg >= dev->n_subdevices)
return -EINVAL;
s = &dev->subdevices[arg];
@ -2048,6 +2077,7 @@ static int do_setrsubd_ioctl(struct comedi_device *dev, unsigned long arg,
struct comedi_file *cfp = file->private_data;
struct comedi_subdevice *s_old, *s_new;
lockdep_assert_held(&dev->mutex);
if (arg >= dev->n_subdevices)
return -EINVAL;
@ -2090,6 +2120,7 @@ static int do_setwsubd_ioctl(struct comedi_device *dev, unsigned long arg,
struct comedi_file *cfp = file->private_data;
struct comedi_subdevice *s_old, *s_new;
lockdep_assert_held(&dev->mutex);
if (arg >= dev->n_subdevices)
return -EINVAL;
@ -2995,6 +3026,7 @@ static int __init comedi_init(void)
goto out_cleanup_board_minors;
}
/* comedi_alloc_board_minor() locked the mutex */
lockdep_assert_held(&dev->mutex);
mutex_unlock(&dev->mutex);
}

View File

@ -159,6 +159,7 @@ static void comedi_device_detach_cleanup(struct comedi_device *dev)
int i;
struct comedi_subdevice *s;
lockdep_assert_held(&dev->mutex);
if (dev->subdevices) {
for (i = 0; i < dev->n_subdevices; i++) {
s = &dev->subdevices[i];
@ -196,6 +197,7 @@ static void comedi_device_detach_cleanup(struct comedi_device *dev)
void comedi_device_detach(struct comedi_device *dev)
{
lockdep_assert_held(&dev->mutex);
comedi_device_cancel_all(dev);
down_write(&dev->attach_lock);
dev->attached = false;
@ -643,6 +645,7 @@ static int __comedi_device_postconfig_async(struct comedi_device *dev,
unsigned int buf_size;
int ret;
lockdep_assert_held(&dev->mutex);
if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) {
dev_warn(dev->class_dev,
"async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
@ -690,6 +693,7 @@ static int __comedi_device_postconfig(struct comedi_device *dev)
int ret;
int i;
lockdep_assert_held(&dev->mutex);
if (!dev->insn_device_config)
dev->insn_device_config = insn_device_inval;
@ -747,6 +751,7 @@ static int comedi_device_postconfig(struct comedi_device *dev)
{
int ret;
lockdep_assert_held(&dev->mutex);
ret = __comedi_device_postconfig(dev);
if (ret < 0)
return ret;
@ -946,6 +951,7 @@ int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
struct comedi_driver *driv;
int ret;
lockdep_assert_held(&dev->mutex);
if (dev->attached)
return -EBUSY;
@ -1053,6 +1059,7 @@ int comedi_auto_config(struct device *hardware_device,
return PTR_ERR(dev);
}
/* Note: comedi_alloc_board_minor() locked dev->mutex. */
lockdep_assert_held(&dev->mutex);
dev->driver = driver;
dev->board_name = dev->driver->driver_name;