From 2cb1599f9b2ecdd7a9e59feeee647eb258966839 Mon Sep 17 00:00:00 2001 From: David Chinner Date: Thu, 30 Oct 2008 17:32:23 +1100 Subject: [PATCH] Inode: Allow external initialisers To allow XFS to combine the XFS and linux inodes into a single structure, we need to drive inode lookup from the XFS inode cache, not the generic inode cache. This means that we need initialise a struct inode from a context outside alloc_inode() as it is no longer used by XFS. Factor and export the struct inode initialisation code from alloc_inode() to inode_init_always() as a counterpart to inode_init_once(). i.e. we have to call this init function for each inode instantiation (always), as opposed inode_init_once() which is only called on slab object instantiation (once). Signed-off-by: Dave Chinner Signed-off-by: Christoph Hellwig Signed-off-by: Lachlan McIlroy --- fs/inode.c | 140 +++++++++++++++++++++++++++++------------------------ include/linux/fs.h | 1 + 2 files changed, 79 insertions(+), 62 deletions(-) diff --git a/fs/inode.c b/fs/inode.c index 0487ddb..e7ee999 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -108,84 +108,100 @@ static void wake_up_inode(struct inode *inode) wake_up_bit(&inode->i_state, __I_LOCK); } -static struct inode *alloc_inode(struct super_block *sb) +/** + * inode_init_always - perform inode structure intialisation + * @sb - superblock inode belongs to. + * @inode - inode to initialise + * + * These are initializations that need to be done on every inode + * allocation as the fields are not initialised by slab allocation. + */ +struct inode *inode_init_always(struct super_block *sb, struct inode *inode) { static const struct address_space_operations empty_aops; static struct inode_operations empty_iops; static const struct file_operations empty_fops; - struct inode *inode; - - if (sb->s_op->alloc_inode) - inode = sb->s_op->alloc_inode(sb); - else - inode = (struct inode *) kmem_cache_alloc(inode_cachep, GFP_KERNEL); - if (inode) { - struct address_space * const mapping = &inode->i_data; - - inode->i_sb = sb; - inode->i_blkbits = sb->s_blocksize_bits; - inode->i_flags = 0; - atomic_set(&inode->i_count, 1); - inode->i_op = &empty_iops; - inode->i_fop = &empty_fops; - inode->i_nlink = 1; - atomic_set(&inode->i_writecount, 0); - inode->i_size = 0; - inode->i_blocks = 0; - inode->i_bytes = 0; - inode->i_generation = 0; + struct address_space * const mapping = &inode->i_data; + + inode->i_sb = sb; + inode->i_blkbits = sb->s_blocksize_bits; + inode->i_flags = 0; + atomic_set(&inode->i_count, 1); + inode->i_op = &empty_iops; + inode->i_fop = &empty_fops; + inode->i_nlink = 1; + atomic_set(&inode->i_writecount, 0); + inode->i_size = 0; + inode->i_blocks = 0; + inode->i_bytes = 0; + inode->i_generation = 0; #ifdef CONFIG_QUOTA - memset(&inode->i_dquot, 0, sizeof(inode->i_dquot)); + memset(&inode->i_dquot, 0, sizeof(inode->i_dquot)); #endif - inode->i_pipe = NULL; - inode->i_bdev = NULL; - inode->i_cdev = NULL; - inode->i_rdev = 0; - inode->dirtied_when = 0; - if (security_inode_alloc(inode)) { - if (inode->i_sb->s_op->destroy_inode) - inode->i_sb->s_op->destroy_inode(inode); - else - kmem_cache_free(inode_cachep, (inode)); - return NULL; - } + inode->i_pipe = NULL; + inode->i_bdev = NULL; + inode->i_cdev = NULL; + inode->i_rdev = 0; + inode->dirtied_when = 0; + if (security_inode_alloc(inode)) { + if (inode->i_sb->s_op->destroy_inode) + inode->i_sb->s_op->destroy_inode(inode); + else + kmem_cache_free(inode_cachep, (inode)); + return NULL; + } - spin_lock_init(&inode->i_lock); - lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key); + spin_lock_init(&inode->i_lock); + lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key); - mutex_init(&inode->i_mutex); - lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key); + mutex_init(&inode->i_mutex); + lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key); - init_rwsem(&inode->i_alloc_sem); - lockdep_set_class(&inode->i_alloc_sem, &sb->s_type->i_alloc_sem_key); + init_rwsem(&inode->i_alloc_sem); + lockdep_set_class(&inode->i_alloc_sem, &sb->s_type->i_alloc_sem_key); - mapping->a_ops = &empty_aops; - mapping->host = inode; - mapping->flags = 0; - mapping_set_gfp_mask(mapping, GFP_HIGHUSER_PAGECACHE); - mapping->assoc_mapping = NULL; - mapping->backing_dev_info = &default_backing_dev_info; - mapping->writeback_index = 0; + mapping->a_ops = &empty_aops; + mapping->host = inode; + mapping->flags = 0; + mapping_set_gfp_mask(mapping, GFP_HIGHUSER_PAGECACHE); + mapping->assoc_mapping = NULL; + mapping->backing_dev_info = &default_backing_dev_info; + mapping->writeback_index = 0; - /* - * If the block_device provides a backing_dev_info for client - * inodes then use that. Otherwise the inode share the bdev's - * backing_dev_info. - */ - if (sb->s_bdev) { - struct backing_dev_info *bdi; + /* + * If the block_device provides a backing_dev_info for client + * inodes then use that. Otherwise the inode share the bdev's + * backing_dev_info. + */ + if (sb->s_bdev) { + struct backing_dev_info *bdi; - bdi = sb->s_bdev->bd_inode_backing_dev_info; - if (!bdi) - bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info; - mapping->backing_dev_info = bdi; - } - inode->i_private = NULL; - inode->i_mapping = mapping; + bdi = sb->s_bdev->bd_inode_backing_dev_info; + if (!bdi) + bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info; + mapping->backing_dev_info = bdi; } + inode->i_private = NULL; + inode->i_mapping = mapping; + return inode; } +EXPORT_SYMBOL(inode_init_always); + +static struct inode *alloc_inode(struct super_block *sb) +{ + struct inode *inode; + + if (sb->s_op->alloc_inode) + inode = sb->s_op->alloc_inode(sb); + else + inode = kmem_cache_alloc(inode_cachep, GFP_KERNEL); + + if (inode) + return inode_init_always(sb, inode); + return NULL; +} void destroy_inode(struct inode *inode) { diff --git a/include/linux/fs.h b/include/linux/fs.h index 5b248d6..04abead 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1881,6 +1881,7 @@ extern loff_t default_llseek(struct file *file, loff_t offset, int origin); extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin); +extern struct inode * inode_init_always(struct super_block *, struct inode *); extern void inode_init_once(struct inode *); extern void iput(struct inode *); extern struct inode * igrab(struct inode *); -- 1.8.2.3