4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Greg Kroah-Hartman gregkh@linuxfoundation.org
This reverts commit 611f77199cd763e6b7c0462c2f199ddb3a089750 which is commit 0a42e99b58a208839626465af194cfe640ef9493 upstream.
It is not needed in the 4.4.y tree at this time.
Reported-by: Jan Kara jack@suse.cz Cc: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/block/loop.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-)
--- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -81,6 +81,7 @@ #include <asm/uaccess.h>
static DEFINE_IDR(loop_index_idr); +static DEFINE_MUTEX(loop_index_mutex); static DEFINE_MUTEX(loop_ctl_mutex);
static int max_part; @@ -1570,11 +1571,9 @@ static int lo_compat_ioctl(struct block_ static int lo_open(struct block_device *bdev, fmode_t mode) { struct loop_device *lo; - int err; + int err = 0;
- err = mutex_lock_killable(&loop_ctl_mutex); - if (err) - return err; + mutex_lock(&loop_index_mutex); lo = bdev->bd_disk->private_data; if (!lo) { err = -ENXIO; @@ -1583,7 +1582,7 @@ static int lo_open(struct block_device *
atomic_inc(&lo->lo_refcnt); out: - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex); return err; }
@@ -1592,11 +1591,12 @@ static void lo_release(struct gendisk *d struct loop_device *lo; int err;
- mutex_lock(&loop_ctl_mutex); + mutex_lock(&loop_index_mutex); lo = disk->private_data; if (atomic_dec_return(&lo->lo_refcnt)) - goto out_unlock; + goto unlock_index;
+ mutex_lock(&loop_ctl_mutex); if (lo->lo_flags & LO_FLAGS_AUTOCLEAR) { /* * In autoclear mode, stop the loop thread @@ -1604,7 +1604,7 @@ static void lo_release(struct gendisk *d */ err = loop_clr_fd(lo); if (!err) - return; + goto unlock_index; } else { /* * Otherwise keep thread (if running) and config, @@ -1613,8 +1613,9 @@ static void lo_release(struct gendisk *d loop_flush(lo); }
-out_unlock: mutex_unlock(&loop_ctl_mutex); +unlock_index: + mutex_unlock(&loop_index_mutex); }
static const struct block_device_operations lo_fops = { @@ -1896,7 +1897,7 @@ static struct kobject *loop_probe(dev_t struct kobject *kobj; int err;
- mutex_lock(&loop_ctl_mutex); + mutex_lock(&loop_index_mutex); err = loop_lookup(&lo, MINOR(dev) >> part_shift); if (err < 0) err = loop_add(&lo, MINOR(dev) >> part_shift); @@ -1904,7 +1905,7 @@ static struct kobject *loop_probe(dev_t kobj = NULL; else kobj = get_disk(lo->lo_disk); - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex);
*part = 0; return kobj; @@ -1914,13 +1915,9 @@ static long loop_control_ioctl(struct fi unsigned long parm) { struct loop_device *lo; - int ret; - - ret = mutex_lock_killable(&loop_ctl_mutex); - if (ret) - return ret; + int ret = -ENOSYS;
- ret = -ENOSYS; + mutex_lock(&loop_index_mutex); switch (cmd) { case LOOP_CTL_ADD: ret = loop_lookup(&lo, parm); @@ -1934,6 +1931,7 @@ static long loop_control_ioctl(struct fi ret = loop_lookup(&lo, parm); if (ret < 0) break; + mutex_lock(&loop_ctl_mutex); if (lo->lo_state != Lo_unbound) { ret = -EBUSY; mutex_unlock(&loop_ctl_mutex); @@ -1945,6 +1943,7 @@ static long loop_control_ioctl(struct fi break; } lo->lo_disk->private_data = NULL; + mutex_unlock(&loop_ctl_mutex); idr_remove(&loop_index_idr, lo->lo_number); loop_remove(lo); break; @@ -1954,7 +1953,7 @@ static long loop_control_ioctl(struct fi break; ret = loop_add(&lo, -1); } - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex);
return ret; } @@ -2037,10 +2036,10 @@ static int __init loop_init(void) THIS_MODULE, loop_probe, NULL, NULL);
/* pre-create number of devices given by config or max_loop */ - mutex_lock(&loop_ctl_mutex); + mutex_lock(&loop_index_mutex); for (i = 0; i < nr; i++) loop_add(&lo, i); - mutex_unlock(&loop_ctl_mutex); + mutex_unlock(&loop_index_mutex);
printk(KERN_INFO "loop: module loaded\n"); return 0;