[PATCH] OCFS2: The Second Oracle Cluster Filesystem

The OCFS2 file system module.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>

1 files changed, 618 insertions, 0 deletions

diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
new file mode 100644
index 000000000000..856e20ae8263
--- /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 <linux/fs.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+
+#define MLOG_MASK_PREFIX ML_NAMEI
+#include <cluster/masklog.h>
+
+#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;
+}