--- /dev/null
+/*
+ * 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;
+}
Code Review / kvmfornfv.git / blobdiff