/* * alloc.h - persistent object (dat entry/disk inode) allocator/deallocator * * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * Original code was written by Koji Sato <koji@osrg.net>. * Two allocators were unified by Ryusuke Konishi <ryusuke@osrg.net>, * Amagai Yoshiji <amagai@osrg.net>. */ #ifndef _NILFS_ALLOC_H #define _NILFS_ALLOC_H #include <linux/types.h> #include <linux/buffer_head.h> #include <linux/fs.h> /** * nilfs_palloc_entries_per_group - get the number of entries per group * @inode: inode of metadata file using this allocator * * The number of entries per group is defined by the number of bits * that a bitmap block can maintain. */ static inline unsigned long nilfs_palloc_entries_per_group(const struct inode *inode) { return 1UL << (inode->i_blkbits + 3 /* log2(8 = CHAR_BITS) */); } int nilfs_palloc_init_blockgroup(struct inode *, unsigned); int nilfs_palloc_get_entry_block(struct inode *, __u64, int, struct buffer_head **); void *nilfs_palloc_block_get_entry(const struct inode *, __u64, const struct buffer_head *, void *); /** * nilfs_palloc_req - persistent allocator request and reply * @pr_entry_nr: entry number (vblocknr or inode number) * @pr_desc_bh: buffer head of the buffer containing block group descriptors * @pr_bitmap_bh: buffer head of the buffer containing a block group bitmap * @pr_entry_bh: buffer head of the buffer containing translation entries */ struct nilfs_palloc_req { __u64 pr_entry_nr; struct buffer_head *pr_desc_bh; struct buffer_head *pr_bitmap_bh; struct buffer_head *pr_entry_bh; }; int nilfs_palloc_prepare_alloc_entry(struct inode *, struct nilfs_palloc_req *); void nilfs_palloc_commit_alloc_entry(struct inode *, struct nilfs_palloc_req *); void nilfs_palloc_abort_alloc_entry(struct inode *, struct nilfs_palloc_req *); void nilfs_palloc_commit_free_entry(struct inode *, struct nilfs_palloc_req *); int nilfs_palloc_prepare_free_entry(struct inode *, struct nilfs_palloc_req *); void nilfs_palloc_abort_free_entry(struct inode *, struct nilfs_palloc_req *); int nilfs_palloc_freev(struct inode *, __u64 *, size_t); #define nilfs_set_bit_atomic ext2_set_bit_atomic #define nilfs_clear_bit_atomic ext2_clear_bit_atomic #define nilfs_find_next_zero_bit find_next_zero_bit_le /** * struct nilfs_bh_assoc - block offset and buffer head association * @blkoff: block offset * @bh: buffer head */ struct nilfs_bh_assoc { unsigned long blkoff; struct buffer_head *bh; }; /** * struct nilfs_palloc_cache - persistent object allocator cache * @lock: cache protecting lock * @prev_desc: blockgroup descriptors cache * @prev_bitmap: blockgroup bitmap cache * @prev_entry: translation entries cache */ struct nilfs_palloc_cache { spinlock_t lock; struct nilfs_bh_assoc prev_desc; struct nilfs_bh_assoc prev_bitmap; struct nilfs_bh_assoc prev_entry; }; void nilfs_palloc_setup_cache(struct inode *inode, struct nilfs_palloc_cache *cache); void nilfs_palloc_clear_cache(struct inode *inode); void nilfs_palloc_destroy_cache(struct inode *inode); #endif /* _NILFS_ALLOC_H */