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| author | Jonathan Corbet <corbet@lwn.net> | 2008-08-26 17:15:45 -0600 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2008-10-16 12:32:26 -0600 |
| commit | 0d4a7bc12ffecd3ba41dd94179cc5b272b71ce8a (patch) | |
| tree | 40fb095468564e1bcd64ee9a01ac409406cc36d3 /drivers/uio | |
| parent | 3fa8749e584b55f1180411ab1b51117190bac1e5 (diff) | |
| download | lwn-0d4a7bc12ffecd3ba41dd94179cc5b272b71ce8a.tar.gz lwn-0d4a7bc12ffecd3ba41dd94179cc5b272b71ce8a.zip | |
UIO: BKL removal
Fill in needed locking around idr accesses, then remove the big kernel lock
from the UIO driver. Since there are no in-tree UIO drivers with open()
methods, no further BKL pushdown is required.
Acked-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'drivers/uio')
| -rw-r--r-- | drivers/uio/uio.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c index 3a6934bf7131..4f28f4bf8366 100644 --- a/drivers/uio/uio.c +++ b/drivers/uio/uio.c @@ -47,6 +47,9 @@ static struct uio_class { struct class *class; } *uio_class; +/* Protect idr accesses */ +static DEFINE_MUTEX(minor_lock); + /* * attributes */ @@ -231,7 +234,6 @@ static void uio_dev_del_attributes(struct uio_device *idev) static int uio_get_minor(struct uio_device *idev) { - static DEFINE_MUTEX(minor_lock); int retval = -ENOMEM; int id; @@ -253,7 +255,9 @@ exit: static void uio_free_minor(struct uio_device *idev) { + mutex_lock(&minor_lock); idr_remove(&uio_idr, idev->minor); + mutex_unlock(&minor_lock); } /** @@ -297,8 +301,9 @@ static int uio_open(struct inode *inode, struct file *filep) struct uio_listener *listener; int ret = 0; - lock_kernel(); + mutex_lock(&minor_lock); idev = idr_find(&uio_idr, iminor(inode)); + mutex_unlock(&minor_lock); if (!idev) { ret = -ENODEV; goto out; @@ -324,18 +329,15 @@ static int uio_open(struct inode *inode, struct file *filep) if (ret) goto err_infoopen; } - unlock_kernel(); return 0; err_infoopen: - kfree(listener); -err_alloc_listener: +err_alloc_listener: module_put(idev->owner); out: - unlock_kernel(); return ret; } |