When mutipath_message is called with an action and a device, it needs to
find the pgpath that matches that device. dm_get_device() is not the
right function for this. dm_get_device() will look for a table_device
matching the requested path in use by either the live or inactive table.
If it doesn't find the device, dm_get_device() will open it and add it
to the table. Means that multipath_message will accept any block device,
add it to the table if not present, and then look through the pgpaths
to see if it finds a match. Afterwards it will remove the device if it
was not previously in the table devices list.
This is the only function that can modify the device list of a table
besides the constructors and destructors, and it can only do this when
it was passed an invalid message. Instead, multipath_message() should
call dm_devt_from_path() to get the device dev_t, and match that against
its pgpaths.
Signed-off-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx>
---
drivers/md/dm-mpath.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 05d1328d1811..a1d08a702709 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1420,8 +1420,7 @@ static int reinstate_path(struct pgpath *pgpath)
/*
* Fail or reinstate all paths that match the provided struct dm_dev.
*/
-static int action_dev(struct multipath *m, struct dm_dev *dev,
- action_fn action)
+static int action_dev(struct multipath *m, dev_t dev, action_fn action)
{
int r = -EINVAL;
struct pgpath *pgpath;
@@ -1429,7 +1428,7 @@ static int action_dev(struct multipath *m, struct dm_dev *dev,
list_for_each_entry(pg, &m->priority_groups, list) {
list_for_each_entry(pgpath, &pg->pgpaths, list) {
- if (pgpath->path.dev == dev)
+ if (pgpath->path.dev->bdev->bd_dev == dev)
r = action(pgpath);
}
}
@@ -1960,7 +1959,7 @@ static int multipath_message(struct dm_target *ti, unsigned int argc, char **arg
char *result, unsigned int maxlen)
{
int r = -EINVAL;
- struct dm_dev *dev;
+ dev_t dev;
struct multipath *m = ti->private;
action_fn action;
unsigned long flags;
@@ -2009,7 +2008,7 @@ static int multipath_message(struct dm_target *ti, unsigned int argc, char **arg
goto out;
}
- r = dm_get_device(ti, argv[1], dm_table_get_mode(ti->table), &dev);
+ r = dm_devt_from_path(argv[1], &dev);
if (r) {
DMWARN("message: error getting device %s",
argv[1]);
@@ -2018,8 +2017,6 @@ static int multipath_message(struct dm_target *ti, unsigned int argc, char **arg
r = action_dev(m, dev, action);
- dm_put_device(ti, dev);
-
out:
mutex_unlock(&m->work_mutex);
return r;
--
2.45.0
