From 3da127fa887e5187ede702b835770634d705f8b2 Mon Sep 17 00:00:00 2001 From: Lars Ellenberg Date: Wed, 24 Nov 2010 10:33:02 +0100 Subject: [PATCH] drbd: increase module count on /proc/drbd access If someone holds /proc/drbd open, previously rmmod would "succeed" in starting the unload, but then block on remove_proc_entry, leading to a situation where the lsmod does not show drbd anymore, but /proc/drbd being still there (but no longer accessible). I'd rather have rmmod fail up front in this case. Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_proc.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/block/drbd/drbd_proc.c b/drivers/block/drbd/drbd_proc.c index 49d817cfe86..efba62cd2e5 100644 --- a/drivers/block/drbd/drbd_proc.c +++ b/drivers/block/drbd/drbd_proc.c @@ -34,6 +34,7 @@ #include "drbd_int.h" static int drbd_proc_open(struct inode *inode, struct file *file); +static int drbd_proc_release(struct inode *inode, struct file *file); struct proc_dir_entry *drbd_proc; @@ -42,7 +43,7 @@ const struct file_operations drbd_proc_fops = { .open = drbd_proc_open, .read = seq_read, .llseek = seq_lseek, - .release = single_release, + .release = drbd_proc_release, }; void seq_printf_with_thousands_grouping(struct seq_file *seq, long v) @@ -304,7 +305,15 @@ static int drbd_seq_show(struct seq_file *seq, void *v) static int drbd_proc_open(struct inode *inode, struct file *file) { - return single_open(file, drbd_seq_show, PDE(inode)->data); + if (try_module_get(THIS_MODULE)) + return single_open(file, drbd_seq_show, PDE(inode)->data); + return -ENODEV; +} + +static int drbd_proc_release(struct inode *inode, struct file *file) +{ + module_put(THIS_MODULE); + return single_release(inode, file); } /* PROC FS stuff end */ -- 2.39.5