| /* |
| * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README |
| */ |
| |
| #include <linux/string.h> |
| #include <linux/errno.h> |
| #include <linux/fs.h> |
| #include "reiserfs.h" |
| #include <linux/stat.h> |
| #include <linux/buffer_head.h> |
| #include <linux/slab.h> |
| #include <linux/uaccess.h> |
| |
| extern const struct reiserfs_key MIN_KEY; |
| |
| static int reiserfs_readdir(struct file *, struct dir_context *); |
| static int reiserfs_dir_fsync(struct file *filp, loff_t start, loff_t end, |
| int datasync); |
| |
| const struct file_operations reiserfs_dir_operations = { |
| .llseek = generic_file_llseek, |
| .read = generic_read_dir, |
| .iterate_shared = reiserfs_readdir, |
| .fsync = reiserfs_dir_fsync, |
| .unlocked_ioctl = reiserfs_ioctl, |
| #ifdef CONFIG_COMPAT |
| .compat_ioctl = reiserfs_compat_ioctl, |
| #endif |
| }; |
| |
| static int reiserfs_dir_fsync(struct file *filp, loff_t start, loff_t end, |
| int datasync) |
| { |
| struct inode *inode = filp->f_mapping->host; |
| int err; |
| |
| err = file_write_and_wait_range(filp, start, end); |
| if (err) |
| return err; |
| |
| inode_lock(inode); |
| reiserfs_write_lock(inode->i_sb); |
| err = reiserfs_commit_for_inode(inode); |
| reiserfs_write_unlock(inode->i_sb); |
| inode_unlock(inode); |
| if (err < 0) |
| return err; |
| return 0; |
| } |
| |
| #define store_ih(where,what) copy_item_head (where, what) |
| |
| static inline bool is_privroot_deh(struct inode *dir, struct reiserfs_de_head *deh) |
| { |
| struct dentry *privroot = REISERFS_SB(dir->i_sb)->priv_root; |
| return (d_really_is_positive(privroot) && |
| deh->deh_objectid == INODE_PKEY(d_inode(privroot))->k_objectid); |
| } |
| |
| int reiserfs_readdir_inode(struct inode *inode, struct dir_context *ctx) |
| { |
| |
| /* key of current position in the directory (key of directory entry) */ |
| struct cpu_key pos_key; |
| |
| INITIALIZE_PATH(path_to_entry); |
| struct buffer_head *bh; |
| int item_num, entry_num; |
| const struct reiserfs_key *rkey; |
| struct item_head *ih, tmp_ih; |
| int search_res; |
| char *local_buf; |
| loff_t next_pos; |
| char small_buf[32]; /* avoid kmalloc if we can */ |
| struct reiserfs_dir_entry de; |
| int ret = 0; |
| int depth; |
| |
| reiserfs_write_lock(inode->i_sb); |
| |
| reiserfs_check_lock_depth(inode->i_sb, "readdir"); |
| |
| /* |
| * form key for search the next directory entry using |
| * f_pos field of file structure |
| */ |
| make_cpu_key(&pos_key, inode, ctx->pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3); |
| next_pos = cpu_key_k_offset(&pos_key); |
| |
| path_to_entry.reada = PATH_READA; |
| while (1) { |
| research: |
| /* |
| * search the directory item, containing entry with |
| * specified key |
| */ |
| search_res = |
| search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry, |
| &de); |
| if (search_res == IO_ERROR) { |
| /* |
| * FIXME: we could just skip part of directory |
| * which could not be read |
| */ |
| ret = -EIO; |
| goto out; |
| } |
| entry_num = de.de_entry_num; |
| bh = de.de_bh; |
| item_num = de.de_item_num; |
| ih = de.de_ih; |
| store_ih(&tmp_ih, ih); |
| |
| /* we must have found item, that is item of this directory, */ |
| RFALSE(COMP_SHORT_KEYS(&ih->ih_key, &pos_key), |
| "vs-9000: found item %h does not match to dir we readdir %K", |
| ih, &pos_key); |
| RFALSE(item_num > B_NR_ITEMS(bh) - 1, |
| "vs-9005 item_num == %d, item amount == %d", |
| item_num, B_NR_ITEMS(bh)); |
| |
| /* |
| * and entry must be not more than number of entries |
| * in the item |
| */ |
| RFALSE(ih_entry_count(ih) < entry_num, |
| "vs-9010: entry number is too big %d (%d)", |
| entry_num, ih_entry_count(ih)); |
| |
| /* |
| * go through all entries in the directory item beginning |
| * from the entry, that has been found |
| */ |
| if (search_res == POSITION_FOUND |
| || entry_num < ih_entry_count(ih)) { |
| struct reiserfs_de_head *deh = |
| B_I_DEH(bh, ih) + entry_num; |
| |
| for (; entry_num < ih_entry_count(ih); |
| entry_num++, deh++) { |
| int d_reclen; |
| char *d_name; |
| ino_t d_ino; |
| loff_t cur_pos = deh_offset(deh); |
| |
| /* it is hidden entry */ |
| if (!de_visible(deh)) |
| continue; |
| d_reclen = entry_length(bh, ih, entry_num); |
| d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh); |
| |
| if (d_reclen <= 0 || |
| d_name + d_reclen > bh->b_data + bh->b_size) { |
| /* |
| * There is corrupted data in entry, |
| * We'd better stop here |
| */ |
| pathrelse(&path_to_entry); |
| ret = -EIO; |
| goto out; |
| } |
| |
| if (!d_name[d_reclen - 1]) |
| d_reclen = strlen(d_name); |
| |
| /* too big to send back to VFS */ |
| if (d_reclen > |
| REISERFS_MAX_NAME(inode->i_sb-> |
| s_blocksize)) { |
| continue; |
| } |
| |
| /* Ignore the .reiserfs_priv entry */ |
| if (is_privroot_deh(inode, deh)) |
| continue; |
| |
| ctx->pos = deh_offset(deh); |
| d_ino = deh_objectid(deh); |
| if (d_reclen <= 32) { |
| local_buf = small_buf; |
| } else { |
| local_buf = kmalloc(d_reclen, |
| GFP_NOFS); |
| if (!local_buf) { |
| pathrelse(&path_to_entry); |
| ret = -ENOMEM; |
| goto out; |
| } |
| if (item_moved(&tmp_ih, &path_to_entry)) { |
| kfree(local_buf); |
| goto research; |
| } |
| } |
| |
| /* |
| * Note, that we copy name to user space via |
| * temporary buffer (local_buf) because |
| * filldir will block if user space buffer is |
| * swapped out. At that time entry can move to |
| * somewhere else |
| */ |
| memcpy(local_buf, d_name, d_reclen); |
| |
| /* |
| * Since filldir might sleep, we can release |
| * the write lock here for other waiters |
| */ |
| depth = reiserfs_write_unlock_nested(inode->i_sb); |
| if (!dir_emit |
| (ctx, local_buf, d_reclen, d_ino, |
| DT_UNKNOWN)) { |
| reiserfs_write_lock_nested(inode->i_sb, depth); |
| if (local_buf != small_buf) { |
| kfree(local_buf); |
| } |
| goto end; |
| } |
| reiserfs_write_lock_nested(inode->i_sb, depth); |
| if (local_buf != small_buf) { |
| kfree(local_buf); |
| } |
| |
| /* deh_offset(deh) may be invalid now. */ |
| next_pos = cur_pos + 1; |
| |
| if (item_moved(&tmp_ih, &path_to_entry)) { |
| set_cpu_key_k_offset(&pos_key, |
| next_pos); |
| goto research; |
| } |
| } /* for */ |
| } |
| |
| /* end of directory has been reached */ |
| if (item_num != B_NR_ITEMS(bh) - 1) |
| goto end; |
| |
| /* |
| * item we went through is last item of node. Using right |
| * delimiting key check is it directory end |
| */ |
| rkey = get_rkey(&path_to_entry, inode->i_sb); |
| if (!comp_le_keys(rkey, &MIN_KEY)) { |
| /* |
| * set pos_key to key, that is the smallest and greater |
| * that key of the last entry in the item |
| */ |
| set_cpu_key_k_offset(&pos_key, next_pos); |
| continue; |
| } |
| |
| /* end of directory has been reached */ |
| if (COMP_SHORT_KEYS(rkey, &pos_key)) { |
| goto end; |
| } |
| |
| /* directory continues in the right neighboring block */ |
| set_cpu_key_k_offset(&pos_key, |
| le_key_k_offset(KEY_FORMAT_3_5, rkey)); |
| |
| } /* while */ |
| |
| end: |
| ctx->pos = next_pos; |
| pathrelse(&path_to_entry); |
| reiserfs_check_path(&path_to_entry); |
| out: |
| reiserfs_write_unlock(inode->i_sb); |
| return ret; |
| } |
| |
| static int reiserfs_readdir(struct file *file, struct dir_context *ctx) |
| { |
| return reiserfs_readdir_inode(file_inode(file), ctx); |
| } |
| |
| /* |
| * compose directory item containing "." and ".." entries (entries are |
| * not aligned to 4 byte boundary) |
| */ |
| void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid, |
| __le32 par_dirid, __le32 par_objid) |
| { |
| struct reiserfs_de_head *dot, *dotdot; |
| |
| memset(body, 0, EMPTY_DIR_SIZE_V1); |
| dot = (struct reiserfs_de_head *)body; |
| dotdot = dot + 1; |
| |
| /* direntry header of "." */ |
| put_deh_offset(dot, DOT_OFFSET); |
| /* these two are from make_le_item_head, and are are LE */ |
| dot->deh_dir_id = dirid; |
| dot->deh_objectid = objid; |
| dot->deh_state = 0; /* Endian safe if 0 */ |
| put_deh_location(dot, EMPTY_DIR_SIZE_V1 - strlen(".")); |
| mark_de_visible(dot); |
| |
| /* direntry header of ".." */ |
| put_deh_offset(dotdot, DOT_DOT_OFFSET); |
| /* key of ".." for the root directory */ |
| /* these two are from the inode, and are are LE */ |
| dotdot->deh_dir_id = par_dirid; |
| dotdot->deh_objectid = par_objid; |
| dotdot->deh_state = 0; /* Endian safe if 0 */ |
| put_deh_location(dotdot, deh_location(dot) - strlen("..")); |
| mark_de_visible(dotdot); |
| |
| /* copy ".." and "." */ |
| memcpy(body + deh_location(dot), ".", 1); |
| memcpy(body + deh_location(dotdot), "..", 2); |
| } |
| |
| /* compose directory item containing "." and ".." entries */ |
| void make_empty_dir_item(char *body, __le32 dirid, __le32 objid, |
| __le32 par_dirid, __le32 par_objid) |
| { |
| struct reiserfs_de_head *dot, *dotdot; |
| |
| memset(body, 0, EMPTY_DIR_SIZE); |
| dot = (struct reiserfs_de_head *)body; |
| dotdot = dot + 1; |
| |
| /* direntry header of "." */ |
| put_deh_offset(dot, DOT_OFFSET); |
| /* these two are from make_le_item_head, and are are LE */ |
| dot->deh_dir_id = dirid; |
| dot->deh_objectid = objid; |
| dot->deh_state = 0; /* Endian safe if 0 */ |
| put_deh_location(dot, EMPTY_DIR_SIZE - ROUND_UP(strlen("."))); |
| mark_de_visible(dot); |
| |
| /* direntry header of ".." */ |
| put_deh_offset(dotdot, DOT_DOT_OFFSET); |
| /* key of ".." for the root directory */ |
| /* these two are from the inode, and are are LE */ |
| dotdot->deh_dir_id = par_dirid; |
| dotdot->deh_objectid = par_objid; |
| dotdot->deh_state = 0; /* Endian safe if 0 */ |
| put_deh_location(dotdot, deh_location(dot) - ROUND_UP(strlen(".."))); |
| mark_de_visible(dotdot); |
| |
| /* copy ".." and "." */ |
| memcpy(body + deh_location(dot), ".", 1); |
| memcpy(body + deh_location(dotdot), "..", 2); |
| } |