| /* -*- 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, last_ra_blk = 0; |
| int i, stored; |
| struct buffer_head * bh, * tmp; |
| struct ocfs2_dir_entry * de; |
| int err; |
| struct inode *inode = filp->f_path.dentry->d_inode; |
| struct super_block * sb = inode->i_sb; |
| unsigned int ra_sectors = 16; |
| int lock_level = 0; |
| |
| mlog_entry("dirino=%llu\n", |
| (unsigned long long)OCFS2_I(inode)->ip_blkno); |
| |
| stored = 0; |
| bh = NULL; |
| |
| error = ocfs2_meta_lock_atime(inode, filp->f_vfsmnt, &lock_level); |
| if (lock_level && error >= 0) { |
| /* We release EX lock which used to update atime |
| * and get PR lock again to reduce contention |
| * on commonly accessed directories. */ |
| ocfs2_meta_unlock(inode, 1); |
| lock_level = 0; |
| error = ocfs2_meta_lock(inode, 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_nolock; |
| } |
| |
| 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 #%llu contains a hole at offset %lld\n", |
| (unsigned long long)OCFS2_I(inode)->ip_blkno, |
| filp->f_pos); |
| filp->f_pos += sb->s_blocksize - offset; |
| continue; |
| } |
| |
| /* The idea here is to begin with 8k read-ahead and to stay |
| * 4k ahead of our current position. |
| * |
| * TODO: Use the pagecache for this. We just need to |
| * make sure it's cluster-safe... */ |
| if (!last_ra_blk |
| || (((last_ra_blk - blk) << 9) <= (ra_sectors / 2))) { |
| for (i = ra_sectors >> (sb->s_blocksize_bits - 9); |
| i > 0; i--) { |
| tmp = ocfs2_bread(inode, ++blk, &err, 1); |
| if (tmp) |
| brelse(tmp); |
| } |
| last_ra_blk = blk; |
| ra_sectors = 8; |
| } |
| |
| 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: |
| ocfs2_meta_unlock(inode, lock_level); |
| |
| bail_nolock: |
| 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; |
| |
| mlog_entry("(name=%.*s, blkno=%p, inode=%p, dirent_bh=%p, dirent=%p)\n", |
| namelen, name, blkno, inode, dirent_bh, dirent); |
| |
| *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 %llu, name '%.*s'\n", |
| (unsigned long long)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 #%llu) - no data block\n", |
| (unsigned long long)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 #%llu) - no `.' or `..'\n", |
| (unsigned long long)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, "dir %llu has a hole at %lu\n", |
| (unsigned long long)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, |
| handle_t *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) { |
| u32 offset = OCFS2_I(dir)->ip_clusters; |
| |
| status = ocfs2_do_extend_allocation(OCFS2_SB(sb), dir, &offset, |
| 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)), |
| &p_blkno, NULL, 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; |
| handle_t *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 %llu (i_size = %lld)\n", |
| (unsigned long long)OCFS2_I(dir)->ip_blkno, dir_i_size); |
| |
| /* 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, fe, &meta_ac); |
| if (status < 0) { |
| if (status != -ENOSPC) |
| mlog_errno(status); |
| goto bail; |
| } |
| } |
| |
| status = ocfs2_reserve_clusters(osb, 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, 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(osb, 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 %llu\n", |
| namelen, (unsigned long long)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; |
| } |