[PATCH] kthread: update loop.c to use kthread

Update loop.c to use a kthread instead of a deprecated kernel_thread for
loop devices.

[akpm@osdl.org: don't change the thread's name]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 12 insertions, 14 deletions

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 3c74ea729f..9dc294a749 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -74,6 +74,7 @@
 #include <linux/completion.h>
 #include <linux/highmem.h>
 #include <linux/gfp.h>
+#include <linux/kthread.h>
 
 #include <asm/uaccess.h>
 
@@ -578,8 +579,6 @@ static int loop_thread(void *data)
         struct loop_device *lo = data;
         struct bio *bio;
 
-        daemonize("loop%d", lo->lo_number);
-
         /*
          * loop can be used in an encrypted device,
          * hence, it mustn't be stopped at all
@@ -592,11 +591,6 @@ static int loop_thread(void *data)
         lo->lo_state = Lo_bound;
         lo->lo_pending = 1;
 
-        /*
-         * complete it, we are running
-         */
-        complete(&lo->lo_done);
-
         for (;;) {
                 int pending;
 
@@ -629,7 +623,6 @@ static int loop_thread(void *data)
                         break;
         }
 
-        complete(&lo->lo_done);
         return 0;
 }
 
@@ -746,6 +739,7 @@ static int loop_set_fd(struct loop_device *lo, struct file *lo_file,
         unsigned lo_blocksize;
         int             lo_flags = 0;
         int             error;
+        struct task_struct *tsk;
         loff_t          size;
 
         /* This is safe, since we have a reference from open(). */
@@ -839,10 +833,11 @@ static int loop_set_fd(struct loop_device *lo, struct file *lo_file,
 
         set_blocksize(bdev, lo_blocksize);
 
-        error = kernel_thread(loop_thread, lo, CLONE_KERNEL);
-        if (error < 0)
+        tsk = kthread_run(loop_thread, lo, "loop%d", lo->lo_number);
+        if (IS_ERR(tsk)) {
+                error = PTR_ERR(tsk);
                 goto out_putf;
-        wait_for_completion(&lo->lo_done);
+        }
         return 0;
 
  out_putf:
@@ -898,6 +893,9 @@ static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev)
         if (lo->lo_state != Lo_bound)
                 return -ENXIO;
 
+        if (!lo->lo_thread)
+                return -EINVAL;
+
         if (lo->lo_refcnt > 1)  /* we needed one fd for the ioctl */
                 return -EBUSY;
 
@@ -911,7 +909,7 @@ static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev)
                 complete(&lo->lo_bh_done);
         spin_unlock_irq(&lo->lo_lock);
 
-        wait_for_completion(&lo->lo_done);
+        kthread_stop(lo->lo_thread);
 
         lo->lo_backing_file = NULL;
 
@@ -924,6 +922,7 @@ static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev)
         lo->lo_sizelimit = 0;
         lo->lo_encrypt_key_size = 0;
         lo->lo_flags = 0;
+        lo->lo_thread = NULL;
         memset(lo->lo_encrypt_key, 0, LO_KEY_SIZE);
         memset(lo->lo_crypt_name, 0, LO_NAME_SIZE);
         memset(lo->lo_file_name, 0, LO_NAME_SIZE);
@@ -1288,7 +1287,6 @@ static int __init loop_init(void)
                 if (!lo->lo_queue)
                         goto out_mem4;
                 mutex_init(&lo->lo_ctl_mutex);
-                init_completion(&lo->lo_done);
                 init_completion(&lo->lo_bh_done);
                 lo->lo_number = i;
                 spin_lock_init(&lo->lo_lock);
diff --git a/include/linux/loop.h b/include/linux/loop.h
index e76c7611d6..bf3d2345ce 100644
--- a/include/linux/loop.h
+++ b/include/linux/loop.h
@@ -59,7 +59,7 @@ struct loop_device {
         struct bio              *lo_bio;
         struct bio              *lo_biotail;
         int                     lo_state;
-        struct completion       lo_done;
+        struct task_struct      *lo_thread;
         struct completion       lo_bh_done;
         struct mutex            lo_ctl_mutex;
         int                     lo_pending;