From 2f2177c8dadbcb08c14f796ac983c5475eca1bd3 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 9 Mar 2010 20:38:48 -0800 Subject: [PATCH] Input: remove BKL, fix input_open_file() locking Holding the BKL in input_open_file seems pointless because it does not protect against updates of input_table, and all open functions from the underlying drivers have proper mutex locking. This makes input_open_file take the input_mutex when accessing the table and no lock when calling into the lower function. Signed-off-by: Arnd Bergmann Acked-by: Thadeu Lima de Souza Cascardo Signed-off-by: Dmitry Torokhov --- drivers/input/input.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/drivers/input/input.c b/drivers/input/input.c index e2dd885..e2aad0a 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -1879,35 +1879,37 @@ static int input_open_file(struct inode *inode, struct file *file) const struct file_operations *old_fops, *new_fops = NULL; int err; - lock_kernel(); + err = mutex_lock_interruptible(&input_mutex); + if (err) + return err; + /* No load-on-demand here? */ handler = input_table[iminor(inode) >> 5]; - if (!handler || !(new_fops = fops_get(handler->fops))) { - err = -ENODEV; - goto out; - } + if (handler) + new_fops = fops_get(handler->fops); + + mutex_unlock(&input_mutex); /* * That's _really_ odd. Usually NULL ->open means "nothing special", * not "no device". Oh, well... */ - if (!new_fops->open) { + if (!new_fops || !new_fops->open) { fops_put(new_fops); err = -ENODEV; goto out; } + old_fops = file->f_op; file->f_op = new_fops; err = new_fops->open(inode, file); - if (err) { fops_put(file->f_op); file->f_op = fops_get(old_fops); } fops_put(old_fops); out: - unlock_kernel(); return err; } -- 1.8.2.3