nilfs2: inode map file
This adds a meta data file which stores on-disk inodes in its data blocks.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Yoshiji Amagai <amagai.yoshiji@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/nilfs2/ifile.c b/fs/nilfs2/ifile.c
new file mode 100644
index 0000000..de86401
--- /dev/null
+++ b/fs/nilfs2/ifile.c
@@ -0,0 +1,150 @@
+/*
+ * ifile.c - NILFS inode file
+ *
+ * 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 Amagai Yoshiji <amagai@osrg.net>.
+ * Revised by Ryusuke Konishi <ryusuke@osrg.net>.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/buffer_head.h>
+#include "nilfs.h"
+#include "mdt.h"
+#include "alloc.h"
+#include "ifile.h"
+
+/**
+ * nilfs_ifile_create_inode - create a new disk inode
+ * @ifile: ifile inode
+ * @out_ino: pointer to a variable to store inode number
+ * @out_bh: buffer_head contains newly allocated disk inode
+ *
+ * Return Value: On success, 0 is returned and the newly allocated inode
+ * number is stored in the place pointed by @ino, and buffer_head pointer
+ * that contains newly allocated disk inode structure is stored in the
+ * place pointed by @out_bh
+ * On error, one of the following negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ *
+ * %-ENOSPC - No inode left.
+ */
+int nilfs_ifile_create_inode(struct inode *ifile, ino_t *out_ino,
+ struct buffer_head **out_bh)
+{
+ struct nilfs_palloc_req req;
+ int ret;
+
+ req.pr_entry_nr = 0; /* 0 says find free inode from beginning of
+ a group. dull code!! */
+ req.pr_entry_bh = NULL;
+
+ ret = nilfs_palloc_prepare_alloc_entry(ifile, &req);
+ if (!ret) {
+ ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 1,
+ &req.pr_entry_bh);
+ if (ret < 0)
+ nilfs_palloc_abort_alloc_entry(ifile, &req);
+ }
+ if (ret < 0) {
+ brelse(req.pr_entry_bh);
+ return ret;
+ }
+ nilfs_palloc_commit_alloc_entry(ifile, &req);
+ nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
+ nilfs_mdt_mark_dirty(ifile);
+ *out_ino = (ino_t)req.pr_entry_nr;
+ *out_bh = req.pr_entry_bh;
+ return 0;
+}
+
+/**
+ * nilfs_ifile_delete_inode - delete a disk inode
+ * @ifile: ifile inode
+ * @ino: inode number
+ *
+ * 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 inode number @ino have not been allocated.
+ */
+int nilfs_ifile_delete_inode(struct inode *ifile, ino_t ino)
+{
+ struct nilfs_palloc_req req = {
+ .pr_entry_nr = ino, .pr_entry_bh = NULL
+ };
+ struct nilfs_inode *raw_inode;
+ void *kaddr;
+ int ret;
+
+ ret = nilfs_palloc_prepare_free_entry(ifile, &req);
+ if (!ret) {
+ ret = nilfs_palloc_get_entry_block(ifile, req.pr_entry_nr, 0,
+ &req.pr_entry_bh);
+ if (ret < 0)
+ nilfs_palloc_abort_free_entry(ifile, &req);
+ }
+ if (ret < 0) {
+ brelse(req.pr_entry_bh);
+ return ret;
+ }
+
+ kaddr = kmap_atomic(req.pr_entry_bh->b_page, KM_USER0);
+ raw_inode = nilfs_palloc_block_get_entry(ifile, req.pr_entry_nr,
+ req.pr_entry_bh, kaddr);
+ raw_inode->i_flags = 0;
+ kunmap_atomic(kaddr, KM_USER0);
+
+ nilfs_mdt_mark_buffer_dirty(req.pr_entry_bh);
+ brelse(req.pr_entry_bh);
+
+ nilfs_palloc_commit_free_entry(ifile, &req);
+
+ return 0;
+}
+
+int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino,
+ struct buffer_head **out_bh)
+{
+ struct super_block *sb = ifile->i_sb;
+ int err;
+
+ if (unlikely(!NILFS_VALID_INODE(sb, ino))) {
+ nilfs_error(sb, __func__, "bad inode number: %lu",
+ (unsigned long) ino);
+ return -EINVAL;
+ }
+
+ err = nilfs_palloc_get_entry_block(ifile, ino, 0, out_bh);
+ if (unlikely(err)) {
+ if (err == -EINVAL)
+ nilfs_error(sb, __func__, "ifile is broken");
+ else
+ nilfs_warning(sb, __func__,
+ "unable to read inode: %lu",
+ (unsigned long) ino);
+ }
+ return err;
+}