/* * dat.c - NILFS disk address translation. * * 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 * * Written by Koji Sato <koji@osrg.net>. */ #include <linux/types.h> #include <linux/buffer_head.h> #include <linux/string.h> #include <linux/errno.h> #include "nilfs.h" #include "mdt.h" #include "alloc.h" #include "dat.h" #define NILFS_CNO_MIN ((__u64)1) #define NILFS_CNO_MAX (~(__u64)0) struct nilfs_dat_info { struct nilfs_mdt_info mi; struct nilfs_palloc_cache palloc_cache; struct nilfs_shadow_map shadow; }; static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat) { return (struct nilfs_dat_info *)NILFS_MDT(dat); } static int nilfs_dat_prepare_entry(struct inode *dat, struct nilfs_palloc_req *req, int create) { return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr, create, &req->pr_entry_bh); } static void nilfs_dat_commit_entry(struct inode *dat, struct nilfs_palloc_req *req) { mark_buffer_dirty(req->pr_entry_bh); nilfs_mdt_mark_dirty(dat); brelse(req->pr_entry_bh); } static void nilfs_dat_abort_entry(struct inode *dat, struct nilfs_palloc_req *req) { brelse(req->pr_entry_bh); } int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req) { int ret; ret = nilfs_palloc_prepare_alloc_entry(dat, req); if (ret < 0) return ret; ret = nilfs_dat_prepare_entry(dat, req, 1); if (ret < 0) nilfs_palloc_abort_alloc_entry(dat, req); return ret; } void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req) { struct nilfs_dat_entry *entry; void *kaddr; kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr, req->pr_entry_bh, kaddr); entry->de_start = cpu_to_le64(NILFS_CNO_MIN); entry->de_end = cpu_to_le64(NILFS_CNO_MAX); entry->de_blocknr = cpu_to_le64(0); kunmap_atomic(kaddr, KM_USER0); nilfs_palloc_commit_alloc_entry(dat, req); nilfs_dat_commit_entry(dat, req); } void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req) { nilfs_dat_abort_entry(dat, req); nilfs_palloc_abort_alloc_entry(dat, req); } static void nilfs_dat_commit_free(struct inode *dat, struct nilfs_palloc_req *req) { struct nilfs_dat_entry *entry; void *kaddr; kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr, req->pr_entry_bh, kaddr); entry->de_start = cpu_to_le64(NILFS_CNO_MIN); entry->de_end = cpu_to_le64(NILFS_CNO_MIN); entry->de_blocknr = cpu_to_le64(0); kunmap_atomic(kaddr, KM_USER0); nilfs_dat_commit_entry(dat, req); nilfs_palloc_commit_free_entry(dat, req); } int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req) { int ret; ret = nilfs_dat_prepare_entry(dat, req, 0); WARN_ON(ret == -ENOENT); return ret; } void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req, sector_t blocknr) { struct nilfs_dat_entry *entry; void *kaddr; kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr, req->pr_entry_bh, kaddr); entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat)); entry->de_blocknr = cpu_to_le64(blocknr); kunmap_atomic(kaddr, KM_USER0); nilfs_dat_commit_entry(dat, req); } int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req) { struct nilfs_dat_entry *entry; __u64 start; sector_t blocknr; void *kaddr; int ret; ret = nilfs_dat_prepare_entry(dat, req, 0); if (ret < 0) { WARN_ON(ret == -ENOENT); return ret; } kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr, req->pr_entry_bh, kaddr); start = le64_to_cpu(entry->de_start); blocknr = le64_to_cpu(entry->de_blocknr); kunmap_atomic(kaddr, KM_USER0); if (blocknr == 0) { ret = nilfs_palloc_prepare_free_entry(dat, req); if (ret < 0) { nilfs_dat_abort_entry(dat, req); return ret; } } return 0; } void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req, int dead) { struct nilfs_dat_entry *entry; __u64 start, end; sector_t blocknr; void *kaddr; kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr, req->pr_entry_bh, kaddr); end = start = le64_to_cpu(entry->de_start); if (!dead) { end = nilfs_mdt_cno(dat); WARN_ON(start > end); } entry->de_end = cpu_to_le64(end); blocknr = le64_to_cpu(entry->de_blocknr); kunmap_atomic(kaddr, KM_USER0); if (blocknr == 0) nilfs_dat_commit_free(dat, req); else nilfs_dat_commit_entry(dat, req); } void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req) { struct nilfs_dat_entry *entry; __u64 start; sector_t blocknr; void *kaddr; kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr, req->pr_entry_bh, kaddr); start = le64_to_cpu(entry->de_start); blocknr = le64_to_cpu(entry->de_blocknr); kunmap_atomic(kaddr, KM_USER0); if (start == nilfs_mdt_cno(dat) && blocknr == 0) nilfs_palloc_abort_free_entry(dat, req); nilfs_dat_abort_entry(dat, req); } int nilfs_dat_prepare_update(struct inode *dat, struct nilfs_palloc_req *oldreq, struct nilfs_palloc_req *newreq) { int ret; ret = nilfs_dat_prepare_end(dat, oldreq); if (!ret) { ret = nilfs_dat_prepare_alloc(dat, newreq); if (ret < 0) nilfs_dat_abort_end(dat, oldreq); } return ret; } void nilfs_dat_commit_update(struct inode *dat, struct nilfs_palloc_req *oldreq, struct nilfs_palloc_req *newreq, int dead) { nilfs_dat_commit_end(dat, oldreq, dead); nilfs_dat_commit_alloc(dat, newreq); } void nilfs_dat_abort_update(struct inode *dat, struct nilfs_palloc_req *oldreq, struct nilfs_palloc_req *newreq) { nilfs_dat_abort_end(dat, oldreq); nilfs_dat_abort_alloc(dat, newreq); } /** * nilfs_dat_mark_dirty - * @dat: DAT file inode * @vblocknr: virtual block number * * Description: * * Return Value: On success, 0 is returned. On error, one of the following * negative error codes is returned. * * %-EIO - I/O error. * * %-ENOMEM - Insufficient amount of memory available. */ int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr) { struct nilfs_palloc_req req; int ret; req.pr_entry_nr = vblocknr; ret = nilfs_dat_prepare_entry(dat, &req, 0); if (ret == 0) nilfs_dat_commit_entry(dat, &req); return ret; } /** * nilfs_dat_freev - free virtual block numbers * @dat: DAT file inode * @vblocknrs: array of virtual block numbers * @nitems: number of virtual block numbers * * Description: nilfs_dat_freev() frees the virtual block numbers specified by * @vblocknrs and @nitems. * * Return Value: On success, 0 is returned. On error, one of the following * negative error codes is returned. * * %-EIO - I/O error. * * %-ENOMEM - Insufficient amount of memory available. * * %-ENOENT - The virtual block number have not been allocated. */ int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems) { return nilfs_palloc_freev(dat, vblocknrs, nitems); } /** * nilfs_dat_move - change a block number * @dat: DAT file inode * @vblocknr: virtual block number * @blocknr: block number * * Description: nilfs_dat_move() changes the block number associated with * @vblocknr to @blocknr. * * Return Value: On success, 0 is returned. On error, one of the following * negative error codes is returned. * * %-EIO - I/O error. * * %-ENOMEM - Insufficient amount of memory available. */ int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr) { struct buffer_head *entry_bh; struct nilfs_dat_entry *entry; void *kaddr; int ret; ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh); if (ret < 0) return ret; /* * The given disk block number (blocknr) is not yet written to * the device at this point. * * To prevent nilfs_dat_translate() from returning the * uncommitted block number, this makes a copy of the entry * buffer and redirects nilfs_dat_translate() to the copy. */ if (!buffer_nilfs_redirected(entry_bh)) { ret = nilfs_mdt_freeze_buffer(dat, entry_bh); if (ret) { brelse(entry_bh); return ret; } } kaddr = kmap_atomic(entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr); if (unlikely(entry->de_blocknr == cpu_to_le64(0))) { printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__, (unsigned long long)vblocknr, (unsigned long long)le64_to_cpu(entry->de_start), (unsigned long long)le64_to_cpu(entry->de_end)); kunmap_atomic(kaddr, KM_USER0); brelse(entry_bh); return -EINVAL; } WARN_ON(blocknr == 0); entry->de_blocknr = cpu_to_le64(blocknr); kunmap_atomic(kaddr, KM_USER0); mark_buffer_dirty(entry_bh); nilfs_mdt_mark_dirty(dat); brelse(entry_bh); return 0; } /** * nilfs_dat_translate - translate a virtual block number to a block number * @dat: DAT file inode * @vblocknr: virtual block number * @blocknrp: pointer to a block number * * Description: nilfs_dat_translate() maps the virtual block number @vblocknr * to the corresponding block number. * * Return Value: On success, 0 is returned and the block number associated * with @vblocknr is stored in the place pointed by @blocknrp. On error, one * of the following negative error codes is returned. * * %-EIO - I/O error. * * %-ENOMEM - Insufficient amount of memory available. * * %-ENOENT - A block number associated with @vblocknr does not exist. */ int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp) { struct buffer_head *entry_bh, *bh; struct nilfs_dat_entry *entry; sector_t blocknr; void *kaddr; int ret; ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh); if (ret < 0) return ret; if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) { bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh); if (bh) { WARN_ON(!buffer_uptodate(bh)); brelse(entry_bh); entry_bh = bh; } } kaddr = kmap_atomic(entry_bh->b_page, KM_USER0); entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr); blocknr = le64_to_cpu(entry->de_blocknr); if (blocknr == 0) { ret = -ENOENT; goto out; } *blocknrp = blocknr; out: kunmap_atomic(kaddr, KM_USER0); brelse(entry_bh); return ret; } ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz, size_t nvi) { struct buffer_head *entry_bh; struct nilfs_dat_entry *entry; struct nilfs_vinfo *vinfo = buf; __u64 first, last; void *kaddr; unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block; int i, j, n, ret; for (i = 0; i < nvi; i += n) { ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr, 0, &entry_bh); if (ret < 0) return ret; kaddr = kmap_atomic(entry_bh->b_page, KM_USER0); /* last virtual block number in this block */ first = vinfo->vi_vblocknr; do_div(first, entries_per_block); first *= entries_per_block; last = first + entries_per_block - 1; for (j = i, n = 0; j < nvi && vinfo->vi_vblocknr >= first && vinfo->vi_vblocknr <= last; j++, n++, vinfo = (void *)vinfo + visz) { entry = nilfs_palloc_block_get_entry( dat, vinfo->vi_vblocknr, entry_bh, kaddr); vinfo->vi_start = le64_to_cpu(entry->de_start); vinfo->vi_end = le64_to_cpu(entry->de_end); vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr); } kunmap_atomic(kaddr, KM_USER0); brelse(entry_bh); } return nvi; } /** * nilfs_dat_read - read or get dat inode * @sb: super block instance * @entry_size: size of a dat entry * @raw_inode: on-disk dat inode * @inodep: buffer to store the inode */ int nilfs_dat_read(struct super_block *sb, size_t entry_size, struct nilfs_inode *raw_inode, struct inode **inodep) { static struct lock_class_key dat_lock_key; struct inode *dat; struct nilfs_dat_info *di; int err; dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO); if (unlikely(!dat)) return -ENOMEM; if (!(dat->i_state & I_NEW)) goto out; err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di)); if (err) goto failed; err = nilfs_palloc_init_blockgroup(dat, entry_size); if (err) goto failed; di = NILFS_DAT_I(dat); lockdep_set_class(&di->mi.mi_sem, &dat_lock_key); nilfs_palloc_setup_cache(dat, &di->palloc_cache); nilfs_mdt_setup_shadow_map(dat, &di->shadow); err = nilfs_read_inode_common(dat, raw_inode); if (err) goto failed; unlock_new_inode(dat); out: *inodep = dat; return 0; failed: iget_failed(dat); return err; }