diff options
Diffstat (limited to 'fs/nilfs2/dat.c')
-rw-r--r-- | fs/nilfs2/dat.c | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/fs/nilfs2/dat.c b/fs/nilfs2/dat.c new file mode 100644 index 0000000..9360920 --- /dev/null +++ b/fs/nilfs2/dat.c @@ -0,0 +1,429 @@ +/* + * 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) + +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) +{ + nilfs_mdt_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); +} + +int nilfs_dat_prepare_free(struct inode *dat, struct nilfs_palloc_req *req) +{ + int ret; + + ret = nilfs_palloc_prepare_free_entry(dat, req); + if (ret < 0) + return ret; + ret = nilfs_dat_prepare_entry(dat, req, 0); + if (ret < 0) { + nilfs_palloc_abort_free_entry(dat, req); + return ret; + } + return 0; +} + +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); +} + +void nilfs_dat_abort_free(struct inode *dat, struct nilfs_palloc_req *req) +{ + nilfs_dat_abort_entry(dat, req); + nilfs_palloc_abort_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); + BUG_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)); + if (entry->de_blocknr != cpu_to_le64(0) || + entry->de_end != cpu_to_le64(NILFS_CNO_MAX)) { + printk(KERN_CRIT + "%s: vbn = %llu, start = %llu, end = %llu, pbn = %llu\n", + __func__, (unsigned long long)req->pr_entry_nr, + (unsigned long long)le64_to_cpu(entry->de_start), + (unsigned long long)le64_to_cpu(entry->de_end), + (unsigned long long)le64_to_cpu(entry->de_blocknr)); + BUG(); + } + entry->de_blocknr = cpu_to_le64(blocknr); + kunmap_atomic(kaddr, KM_USER0); + + nilfs_dat_commit_entry(dat, req); +} + +void nilfs_dat_abort_start(struct inode *dat, struct nilfs_palloc_req *req) +{ + nilfs_dat_abort_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) { + BUG_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); + BUG_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); +} + +/** + * 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 + * nagative 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; + kaddr = kmap_atomic(entry_bh->b_page, KM_USER0); + entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr); + if (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)); + BUG(); + } + BUG_ON(blocknr == 0); + entry->de_blocknr = cpu_to_le64(blocknr); + kunmap_atomic(kaddr, KM_USER0); + + nilfs_mdt_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; + 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; + + 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; + } + if (blocknrp != NULL) + *blocknrp = blocknr; + + out: + kunmap_atomic(kaddr, KM_USER0); + brelse(entry_bh); + return ret; +} + +ssize_t nilfs_dat_get_vinfo(struct inode *dat, struct nilfs_vinfo *vinfo, + size_t nvi) +{ + struct buffer_head *entry_bh; + struct nilfs_dat_entry *entry; + __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[i].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[i].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[j].vi_vblocknr >= first && + vinfo[j].vi_vblocknr <= last; + j++, n++) { + entry = nilfs_palloc_block_get_entry( + dat, vinfo[j].vi_vblocknr, entry_bh, kaddr); + vinfo[j].vi_start = le64_to_cpu(entry->de_start); + vinfo[j].vi_end = le64_to_cpu(entry->de_end); + vinfo[j].vi_blocknr = le64_to_cpu(entry->de_blocknr); + } + kunmap_atomic(kaddr, KM_USER0); + brelse(entry_bh); + } + + return nvi; +} |