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-rw-r--r--fs/ocfs2/dir.c618
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..57158fa75d91
--- /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_mutex 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_mutex + 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;
+}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-04 02:10:50 +0300