diff options
Diffstat (limited to 'fs/nilfs2/dat.c')
| -rw-r--r-- | fs/nilfs2/dat.c | 529 |
1 files changed, 529 insertions, 0 deletions
diff --git a/fs/nilfs2/dat.c b/fs/nilfs2/dat.c new file mode 100644 index 000000000..0d5fada91 --- /dev/null +++ b/fs/nilfs2/dat.c @@ -0,0 +1,529 @@ +/* + * 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 - on-memory private data of DAT file + * @mi: on-memory private data of metadata file + * @palloc_cache: persistent object allocator cache of DAT file + * @shadow: shadow map of DAT file + */ +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); + 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); + + 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); + 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); + + 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); + 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); + + 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); + 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); + + 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); + 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); + + 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); + 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); + + 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); + 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); + brelse(entry_bh); + return -EINVAL; + } + WARN_ON(blocknr == 0); + entry->de_blocknr = cpu_to_le64(blocknr); + kunmap_atomic(kaddr); + + 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); + 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); + 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); + /* 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); + 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; + + if (entry_size > sb->s_blocksize) { + printk(KERN_ERR + "NILFS: too large DAT entry size: %zu bytes.\n", + entry_size); + return -EINVAL; + } else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) { + printk(KERN_ERR + "NILFS: too small DAT entry size: %zu bytes.\n", + entry_size); + return -EINVAL; + } + + 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; +} |