diff mbox

[2/3] fs: super: switch to using ida_simple_.. functions

Message ID f97d03de-d3e6-9ae5-413c-ec3d92f7c9a8@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Heiner Kallweit July 26, 2016, 5:33 a.m. UTC
Ida handling can be much simplified using the ida_simple_.. functions.
This also removes the need for an own spinlock.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 fs/super.c | 29 ++++++-----------------------
 1 file changed, 6 insertions(+), 23 deletions(-)
diff mbox

Patch

diff --git a/fs/super.c b/fs/super.c
index 362e765..37de8f5 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -880,34 +880,20 @@  void emergency_remount(void)
  */
 
 static DEFINE_IDA(unnamed_dev_ida);
-static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */
 
 int get_anon_bdev(dev_t *p)
 {
 	int dev;
-	int error;
 
- retry:
-	if (ida_pre_get(&unnamed_dev_ida, GFP_ATOMIC) == 0)
-		return -ENOMEM;
-	spin_lock(&unnamed_dev_lock);
 	/* Many userspace utilities consider an FSID of 0 invalid.
 	 * Always return at least 1 from get_anon_bdev.
 	 */
-	error = ida_get_new_above(&unnamed_dev_ida, 1, &dev);
-	spin_unlock(&unnamed_dev_lock);
-	if (error == -EAGAIN)
-		/* We raced and lost with another CPU. */
-		goto retry;
-	else if (error)
-		return -EAGAIN;
-
-	if (dev >= (1 << MINORBITS)) {
-		spin_lock(&unnamed_dev_lock);
-		ida_remove(&unnamed_dev_ida, dev);
-		spin_unlock(&unnamed_dev_lock);
+	dev = ida_simple_get(&unnamed_dev_ida, 1, 1 << MINORBITS, GFP_ATOMIC);
+	if (dev == -ENOSPC)
 		return -EMFILE;
-	}
+	else if (dev < 0)
+		return dev;
+
 	*p = MKDEV(0, dev & MINORMASK);
 	return 0;
 }
@@ -915,10 +901,7 @@  EXPORT_SYMBOL(get_anon_bdev);
 
 void free_anon_bdev(dev_t dev)
 {
-	int slot = MINOR(dev);
-	spin_lock(&unnamed_dev_lock);
-	ida_remove(&unnamed_dev_ida, slot);
-	spin_unlock(&unnamed_dev_lock);
+	ida_simple_remove(&unnamed_dev_ida, MINOR(dev));
 }
 EXPORT_SYMBOL(free_anon_bdev);