vfs: Create function for iterating over block devices

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Jan Kara 2012-07-03 16:45:31 +02:00 committed by Al Viro
parent b3de653105
commit 5c0d6b60a0
2 changed files with 41 additions and 0 deletions

View File

@ -1710,3 +1710,39 @@ int __invalidate_device(struct block_device *bdev, bool kill_dirty)
return res; return res;
} }
EXPORT_SYMBOL(__invalidate_device); EXPORT_SYMBOL(__invalidate_device);
void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
{
struct inode *inode, *old_inode = NULL;
spin_lock(&inode_sb_list_lock);
list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
struct address_space *mapping = inode->i_mapping;
spin_lock(&inode->i_lock);
if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
mapping->nrpages == 0) {
spin_unlock(&inode->i_lock);
continue;
}
__iget(inode);
spin_unlock(&inode->i_lock);
spin_unlock(&inode_sb_list_lock);
/*
* We hold a reference to 'inode' so it couldn't have been
* removed from s_inodes list while we dropped the
* inode_sb_list_lock. We cannot iput the inode now as we can
* be holding the last reference and we cannot iput it under
* inode_sb_list_lock. So we keep the reference and iput it
* later.
*/
iput(old_inode);
old_inode = inode;
func(I_BDEV(inode), arg);
spin_lock(&inode_sb_list_lock);
}
spin_unlock(&inode_sb_list_lock);
iput(old_inode);
}

View File

@ -2102,6 +2102,7 @@ extern sector_t blkdev_max_block(struct block_device *bdev);
extern void bd_forget(struct inode *inode); extern void bd_forget(struct inode *inode);
extern void bdput(struct block_device *); extern void bdput(struct block_device *);
extern void invalidate_bdev(struct block_device *); extern void invalidate_bdev(struct block_device *);
extern void iterate_bdevs(void (*)(struct block_device *, void *), void *);
extern int sync_blockdev(struct block_device *bdev); extern int sync_blockdev(struct block_device *bdev);
extern void kill_bdev(struct block_device *); extern void kill_bdev(struct block_device *);
extern struct super_block *freeze_bdev(struct block_device *); extern struct super_block *freeze_bdev(struct block_device *);
@ -2123,6 +2124,10 @@ static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
{ {
return 0; return 0;
} }
static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
{
}
#endif #endif
extern int sync_filesystem(struct super_block *); extern int sync_filesystem(struct super_block *);
extern const struct file_operations def_blk_fops; extern const struct file_operations def_blk_fops;