From ccd979bdbce9fba8412beb3f1de68a9d0171b12c Mon Sep 17 00:00:00 2001 From: Mark Fasheh Date: Thu, 15 Dec 2005 14:31:24 -0800 Subject: [PATCH] OCFS2: The Second Oracle Cluster Filesystem The OCFS2 file system module. Signed-off-by: Mark Fasheh Signed-off-by: Kurt Hackel --- fs/ocfs2/dir.c | 618 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 618 insertions(+) create mode 100644 fs/ocfs2/dir.c (limited to 'fs/ocfs2/dir.c') diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c new file mode 100644 index 00000000000000..856e20ae826370 --- /dev/null +++ b/fs/ocfs2/dir.c @@ -0,0 +1,618 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * dir.c + * + * Creates, reads, walks and deletes directory-nodes + * + * Copyright (C) 2002, 2004 Oracle. All rights reserved. + * + * Portions of this code from linux/fs/ext3/dir.c + * + * Copyright (C) 1992, 1993, 1994, 1995 + * Remy Card (card@masi.ibp.fr) + * Laboratoire MASI - Institut Blaise pascal + * Universite Pierre et Marie Curie (Paris VI) + * + * from + * + * linux/fs/minix/dir.c + * + * Copyright (C) 1991, 1992 Linux Torvalds + * + * 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., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include +#include +#include +#include + +#define MLOG_MASK_PREFIX ML_NAMEI +#include + +#include "ocfs2.h" + +#include "alloc.h" +#include "dir.h" +#include "dlmglue.h" +#include "extent_map.h" +#include "file.h" +#include "inode.h" +#include "journal.h" +#include "namei.h" +#include "suballoc.h" +#include "uptodate.h" + +#include "buffer_head_io.h" + +static unsigned char ocfs2_filetype_table[] = { + DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK +}; + +static int ocfs2_extend_dir(struct ocfs2_super *osb, + struct inode *dir, + struct buffer_head *parent_fe_bh, + struct buffer_head **new_de_bh); +/* + * ocfs2_readdir() + * + */ +int ocfs2_readdir(struct file * filp, void * dirent, filldir_t filldir) +{ + int error = 0; + unsigned long offset, blk; + int i, num, stored; + struct buffer_head * bh, * tmp; + struct ocfs2_dir_entry * de; + int err; + struct inode *inode = filp->f_dentry->d_inode; + struct super_block * sb = inode->i_sb; + int have_disk_lock = 0; + + mlog_entry("dirino=%"MLFu64"\n", OCFS2_I(inode)->ip_blkno); + + stored = 0; + bh = NULL; + + error = ocfs2_meta_lock(inode, NULL, NULL, 0); + if (error < 0) { + if (error != -ENOENT) + mlog_errno(error); + /* we haven't got any yet, so propagate the error. */ + stored = error; + goto bail; + } + have_disk_lock = 1; + + offset = filp->f_pos & (sb->s_blocksize - 1); + + while (!error && !stored && filp->f_pos < i_size_read(inode)) { + blk = (filp->f_pos) >> sb->s_blocksize_bits; + bh = ocfs2_bread(inode, blk, &err, 0); + if (!bh) { + mlog(ML_ERROR, "directory #%"MLFu64" contains a hole " + "at offset %lld\n", + OCFS2_I(inode)->ip_blkno, + filp->f_pos); + filp->f_pos += sb->s_blocksize - offset; + continue; + } + + /* + * Do the readahead (8k) + */ + if (!offset) { + for (i = 16 >> (sb->s_blocksize_bits - 9), num = 0; + i > 0; i--) { + tmp = ocfs2_bread(inode, ++blk, &err, 1); + if (tmp) + brelse(tmp); + } + } + +revalidate: + /* If the dir block has changed since the last call to + * readdir(2), then we might be pointing to an invalid + * dirent right now. Scan from the start of the block + * to make sure. */ + if (filp->f_version != inode->i_version) { + for (i = 0; i < sb->s_blocksize && i < offset; ) { + de = (struct ocfs2_dir_entry *) (bh->b_data + i); + /* It's too expensive to do a full + * dirent test each time round this + * loop, but we do have to test at + * least that it is non-zero. A + * failure will be detected in the + * dirent test below. */ + if (le16_to_cpu(de->rec_len) < + OCFS2_DIR_REC_LEN(1)) + break; + i += le16_to_cpu(de->rec_len); + } + offset = i; + filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1)) + | offset; + filp->f_version = inode->i_version; + } + + while (!error && filp->f_pos < i_size_read(inode) + && offset < sb->s_blocksize) { + de = (struct ocfs2_dir_entry *) (bh->b_data + offset); + if (!ocfs2_check_dir_entry(inode, de, bh, offset)) { + /* On error, skip the f_pos to the + next block. */ + filp->f_pos = (filp->f_pos | + (sb->s_blocksize - 1)) + 1; + brelse(bh); + goto bail; + } + offset += le16_to_cpu(de->rec_len); + if (le64_to_cpu(de->inode)) { + /* We might block in the next section + * if the data destination is + * currently swapped out. So, use a + * version stamp to detect whether or + * not the directory has been modified + * during the copy operation. + */ + unsigned long version = filp->f_version; + unsigned char d_type = DT_UNKNOWN; + + if (de->file_type < OCFS2_FT_MAX) + d_type = ocfs2_filetype_table[de->file_type]; + error = filldir(dirent, de->name, + de->name_len, + filp->f_pos, + ino_from_blkno(sb, le64_to_cpu(de->inode)), + d_type); + if (error) + break; + if (version != filp->f_version) + goto revalidate; + stored ++; + } + filp->f_pos += le16_to_cpu(de->rec_len); + } + offset = 0; + brelse(bh); + } + + stored = 0; +bail: + if (have_disk_lock) + ocfs2_meta_unlock(inode, 0); + + mlog_exit(stored); + + return stored; +} + +/* + * NOTE: this should always be called with parent dir i_sem taken. + */ +int ocfs2_find_files_on_disk(const char *name, + int namelen, + u64 *blkno, + struct inode *inode, + struct buffer_head **dirent_bh, + struct ocfs2_dir_entry **dirent) +{ + int status = -ENOENT; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + + mlog_entry("(osb=%p, parent=%"MLFu64", name='%.*s', blkno=%p, " + "inode=%p)\n", + osb, OCFS2_I(inode)->ip_blkno, namelen, name, blkno, inode); + + *dirent_bh = ocfs2_find_entry(name, namelen, inode, dirent); + if (!*dirent_bh || !*dirent) { + status = -ENOENT; + goto leave; + } + + *blkno = le64_to_cpu((*dirent)->inode); + + status = 0; +leave: + if (status < 0) { + *dirent = NULL; + if (*dirent_bh) { + brelse(*dirent_bh); + *dirent_bh = NULL; + } + } + + mlog_exit(status); + return status; +} + +/* Check for a name within a directory. + * + * Return 0 if the name does not exist + * Return -EEXIST if the directory contains the name + * + * Callers should have i_sem + a cluster lock on dir + */ +int ocfs2_check_dir_for_entry(struct inode *dir, + const char *name, + int namelen) +{ + int ret; + struct buffer_head *dirent_bh = NULL; + struct ocfs2_dir_entry *dirent = NULL; + + mlog_entry("dir %"MLFu64", name '%.*s'\n", OCFS2_I(dir)->ip_blkno, + namelen, name); + + ret = -EEXIST; + dirent_bh = ocfs2_find_entry(name, namelen, dir, &dirent); + if (dirent_bh) + goto bail; + + ret = 0; +bail: + if (dirent_bh) + brelse(dirent_bh); + + mlog_exit(ret); + return ret; +} + +/* + * routine to check that the specified directory is empty (for rmdir) + */ +int ocfs2_empty_dir(struct inode *inode) +{ + unsigned long offset; + struct buffer_head * bh; + struct ocfs2_dir_entry * de, * de1; + struct super_block * sb; + int err; + + sb = inode->i_sb; + if ((i_size_read(inode) < + (OCFS2_DIR_REC_LEN(1) + OCFS2_DIR_REC_LEN(2))) || + !(bh = ocfs2_bread(inode, 0, &err, 0))) { + mlog(ML_ERROR, "bad directory (dir #%"MLFu64") - " + "no data block\n", + OCFS2_I(inode)->ip_blkno); + return 1; + } + + de = (struct ocfs2_dir_entry *) bh->b_data; + de1 = (struct ocfs2_dir_entry *) + ((char *)de + le16_to_cpu(de->rec_len)); + if ((le64_to_cpu(de->inode) != OCFS2_I(inode)->ip_blkno) || + !le64_to_cpu(de1->inode) || + strcmp(".", de->name) || + strcmp("..", de1->name)) { + mlog(ML_ERROR, "bad directory (dir #%"MLFu64") - " + "no `.' or `..'\n", + OCFS2_I(inode)->ip_blkno); + brelse(bh); + return 1; + } + offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len); + de = (struct ocfs2_dir_entry *)((char *)de1 + le16_to_cpu(de1->rec_len)); + while (offset < i_size_read(inode) ) { + if (!bh || (void *)de >= (void *)(bh->b_data + sb->s_blocksize)) { + brelse(bh); + bh = ocfs2_bread(inode, + offset >> sb->s_blocksize_bits, &err, 0); + if (!bh) { + mlog(ML_ERROR, "directory #%"MLFu64" contains " + "a hole at offset %lu\n", + OCFS2_I(inode)->ip_blkno, offset); + offset += sb->s_blocksize; + continue; + } + de = (struct ocfs2_dir_entry *) bh->b_data; + } + if (!ocfs2_check_dir_entry(inode, de, bh, offset)) { + brelse(bh); + return 1; + } + if (le64_to_cpu(de->inode)) { + brelse(bh); + return 0; + } + offset += le16_to_cpu(de->rec_len); + de = (struct ocfs2_dir_entry *) + ((char *)de + le16_to_cpu(de->rec_len)); + } + brelse(bh); + return 1; +} + +/* returns a bh of the 1st new block in the allocation. */ +int ocfs2_do_extend_dir(struct super_block *sb, + struct ocfs2_journal_handle *handle, + struct inode *dir, + struct buffer_head *parent_fe_bh, + struct ocfs2_alloc_context *data_ac, + struct ocfs2_alloc_context *meta_ac, + struct buffer_head **new_bh) +{ + int status; + int extend; + u64 p_blkno; + + spin_lock(&OCFS2_I(dir)->ip_lock); + extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)); + spin_unlock(&OCFS2_I(dir)->ip_lock); + + if (extend) { + status = ocfs2_do_extend_allocation(OCFS2_SB(sb), dir, 1, + parent_fe_bh, handle, + data_ac, meta_ac, NULL); + BUG_ON(status == -EAGAIN); + if (status < 0) { + mlog_errno(status); + goto bail; + } + } + + status = ocfs2_extent_map_get_blocks(dir, (dir->i_blocks >> + (sb->s_blocksize_bits - 9)), + 1, &p_blkno, NULL); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + *new_bh = sb_getblk(sb, p_blkno); + if (!*new_bh) { + status = -EIO; + mlog_errno(status); + goto bail; + } + status = 0; +bail: + mlog_exit(status); + return status; +} + +/* assumes you already have a cluster lock on the directory. */ +static int ocfs2_extend_dir(struct ocfs2_super *osb, + struct inode *dir, + struct buffer_head *parent_fe_bh, + struct buffer_head **new_de_bh) +{ + int status = 0; + int credits, num_free_extents; + loff_t dir_i_size; + struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data; + struct ocfs2_alloc_context *data_ac = NULL; + struct ocfs2_alloc_context *meta_ac = NULL; + struct ocfs2_journal_handle *handle = NULL; + struct buffer_head *new_bh = NULL; + struct ocfs2_dir_entry * de; + struct super_block *sb = osb->sb; + + mlog_entry_void(); + + dir_i_size = i_size_read(dir); + mlog(0, "extending dir %"MLFu64" (i_size = %lld)\n", + OCFS2_I(dir)->ip_blkno, dir_i_size); + + handle = ocfs2_alloc_handle(osb); + if (handle == NULL) { + status = -ENOMEM; + mlog_errno(status); + goto bail; + } + + /* dir->i_size is always block aligned. */ + spin_lock(&OCFS2_I(dir)->ip_lock); + if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) { + spin_unlock(&OCFS2_I(dir)->ip_lock); + num_free_extents = ocfs2_num_free_extents(osb, dir, fe); + if (num_free_extents < 0) { + status = num_free_extents; + mlog_errno(status); + goto bail; + } + + if (!num_free_extents) { + status = ocfs2_reserve_new_metadata(osb, handle, + fe, &meta_ac); + if (status < 0) { + if (status != -ENOSPC) + mlog_errno(status); + goto bail; + } + } + + status = ocfs2_reserve_clusters(osb, handle, 1, &data_ac); + if (status < 0) { + if (status != -ENOSPC) + mlog_errno(status); + goto bail; + } + + credits = ocfs2_calc_extend_credits(sb, fe, 1); + } else { + spin_unlock(&OCFS2_I(dir)->ip_lock); + credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS; + } + + handle = ocfs2_start_trans(osb, handle, credits); + if (IS_ERR(handle)) { + status = PTR_ERR(handle); + handle = NULL; + mlog_errno(status); + goto bail; + } + + status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh, + data_ac, meta_ac, &new_bh); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + ocfs2_set_new_buffer_uptodate(dir, new_bh); + + status = ocfs2_journal_access(handle, dir, new_bh, + OCFS2_JOURNAL_ACCESS_CREATE); + if (status < 0) { + mlog_errno(status); + goto bail; + } + memset(new_bh->b_data, 0, sb->s_blocksize); + de = (struct ocfs2_dir_entry *) new_bh->b_data; + de->inode = 0; + de->rec_len = cpu_to_le16(sb->s_blocksize); + status = ocfs2_journal_dirty(handle, new_bh); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + dir_i_size += dir->i_sb->s_blocksize; + i_size_write(dir, dir_i_size); + dir->i_blocks = ocfs2_align_bytes_to_sectors(dir_i_size); + status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + *new_de_bh = new_bh; + get_bh(*new_de_bh); +bail: + if (handle) + ocfs2_commit_trans(handle); + + if (data_ac) + ocfs2_free_alloc_context(data_ac); + if (meta_ac) + ocfs2_free_alloc_context(meta_ac); + + if (new_bh) + brelse(new_bh); + + mlog_exit(status); + return status; +} + +/* + * Search the dir for a good spot, extending it if necessary. The + * block containing an appropriate record is returned in ret_de_bh. + */ +int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb, + struct inode *dir, + struct buffer_head *parent_fe_bh, + const char *name, + int namelen, + struct buffer_head **ret_de_bh) +{ + unsigned long offset; + struct buffer_head * bh = NULL; + unsigned short rec_len; + struct ocfs2_dinode *fe; + struct ocfs2_dir_entry *de; + struct super_block *sb; + int status; + + mlog_entry_void(); + + mlog(0, "getting ready to insert namelen %d into dir %"MLFu64"\n", + namelen, OCFS2_I(dir)->ip_blkno); + + BUG_ON(!S_ISDIR(dir->i_mode)); + fe = (struct ocfs2_dinode *) parent_fe_bh->b_data; + BUG_ON(le64_to_cpu(fe->i_size) != i_size_read(dir)); + + sb = dir->i_sb; + + if (!namelen) { + status = -EINVAL; + mlog_errno(status); + goto bail; + } + + bh = ocfs2_bread(dir, 0, &status, 0); + if (!bh) { + mlog_errno(status); + goto bail; + } + + rec_len = OCFS2_DIR_REC_LEN(namelen); + offset = 0; + de = (struct ocfs2_dir_entry *) bh->b_data; + while (1) { + if ((char *)de >= sb->s_blocksize + bh->b_data) { + brelse(bh); + bh = NULL; + + if (i_size_read(dir) <= offset) { + status = ocfs2_extend_dir(osb, + dir, + parent_fe_bh, + &bh); + if (status < 0) { + mlog_errno(status); + goto bail; + } + BUG_ON(!bh); + *ret_de_bh = bh; + get_bh(*ret_de_bh); + goto bail; + } + bh = ocfs2_bread(dir, + offset >> sb->s_blocksize_bits, + &status, + 0); + if (!bh) { + mlog_errno(status); + goto bail; + } + /* move to next block */ + de = (struct ocfs2_dir_entry *) bh->b_data; + } + if (!ocfs2_check_dir_entry(dir, de, bh, offset)) { + status = -ENOENT; + goto bail; + } + if (ocfs2_match(namelen, name, de)) { + status = -EEXIST; + goto bail; + } + if (((le64_to_cpu(de->inode) == 0) && + (le16_to_cpu(de->rec_len) >= rec_len)) || + (le16_to_cpu(de->rec_len) >= + (OCFS2_DIR_REC_LEN(de->name_len) + rec_len))) { + /* Ok, we found a spot. Return this bh and let + * the caller actually fill it in. */ + *ret_de_bh = bh; + get_bh(*ret_de_bh); + status = 0; + goto bail; + } + offset += le16_to_cpu(de->rec_len); + de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len)); + } + + status = 0; +bail: + if (bh) + brelse(bh); + + mlog_exit(status); + return status; +} -- cgit 1.2.3-korg