fs: Convert unnamed_dev_ida to new API (5a66847e) · Commits · 戴 / test

fs/super.c

+24 −43

Original line number	Diff line number	Diff line
		@@ -978,58 +978,42 @@ void emergency_thaw_all(void)
		}
		}

		/*
		* Unnamed block devices are dummy devices used by virtual
		* filesystems which don't use real block-devices. -- jrs
		*/

		static DEFINE_IDA(unnamed_dev_ida);
		static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */
		/* Many userspace utilities consider an FSID of 0 invalid.
		* Always return at least 1 from get_anon_bdev.
		*/
		static int unnamed_dev_start = 1;

		/**
		* get_anon_bdev - Allocate a block device for filesystems which don't have one.
		* @p: Pointer to a dev_t.
		*
		* Filesystems which don't use real block devices can call this function
		* to allocate a virtual block device.
		*
		* Context: Any context. Frequently called while holding sb_lock.
		* Return: 0 on success, -EMFILE if there are no anonymous bdevs left
		* or -ENOMEM if memory allocation failed.
		*/
		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);
		error = ida_get_new_above(&unnamed_dev_ida, unnamed_dev_start, &dev);
		if (!error)
		unnamed_dev_start = dev + 1;
		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);
		if (unnamed_dev_start > dev)
		unnamed_dev_start = dev;
		spin_unlock(&unnamed_dev_lock);
		return -EMFILE;
		}
		*p = MKDEV(0, dev & MINORMASK);
		/*
		* Many userspace utilities consider an FSID of 0 invalid.
		* Always return at least 1 from get_anon_bdev.
		*/
		dev = ida_alloc_range(&unnamed_dev_ida, 1, (1 << MINORBITS) - 1,
		GFP_ATOMIC);
		if (dev == -ENOSPC)
		dev = -EMFILE;
		if (dev < 0)
		return dev;

		*p = MKDEV(0, dev);
		return 0;
		}
		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);
		if (slot < unnamed_dev_start)
		unnamed_dev_start = slot;
		spin_unlock(&unnamed_dev_lock);
		ida_free(&unnamed_dev_ida, MINOR(dev));
		}
		EXPORT_SYMBOL(free_anon_bdev);

		@@ -1037,7 +1021,6 @@ int set_anon_super(struct super_block s, void data)
		{
		return get_anon_bdev(&s->s_dev);
		}

		EXPORT_SYMBOL(set_anon_super);

		void kill_anon_super(struct super_block *sb)
		@@ -1046,7 +1029,6 @@ void kill_anon_super(struct super_block *sb)
		generic_shutdown_super(sb);
		free_anon_bdev(dev);
		}

		EXPORT_SYMBOL(kill_anon_super);

		void kill_litter_super(struct super_block *sb)
		@@ -1055,7 +1037,6 @@ void kill_litter_super(struct super_block *sb)
		d_genocide(sb->s_root);
		kill_anon_super(sb);
		}

		EXPORT_SYMBOL(kill_litter_super);

		static int ns_test_super(struct super_block sb, void data)

Admin message