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1/*2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README3 */4 5#include <linux/string.h>6#include <linux/errno.h>7#include <linux/fs.h>8#include "reiserfs.h"9#include <linux/stat.h>10#include <linux/buffer_head.h>11#include <linux/slab.h>12#include <linux/uaccess.h>13 14extern const struct reiserfs_key MIN_KEY;15 16static int reiserfs_readdir(struct file *, struct dir_context *);17static int reiserfs_dir_fsync(struct file *filp, loff_t start, loff_t end,18 int datasync);19 20const struct file_operations reiserfs_dir_operations = {21 .llseek = generic_file_llseek,22 .read = generic_read_dir,23 .iterate_shared = reiserfs_readdir,24 .fsync = reiserfs_dir_fsync,25 .unlocked_ioctl = reiserfs_ioctl,26#ifdef CONFIG_COMPAT27 .compat_ioctl = reiserfs_compat_ioctl,28#endif29};30 31static int reiserfs_dir_fsync(struct file *filp, loff_t start, loff_t end,32 int datasync)33{34 struct inode *inode = filp->f_mapping->host;35 int err;36 37 err = file_write_and_wait_range(filp, start, end);38 if (err)39 return err;40 41 inode_lock(inode);42 reiserfs_write_lock(inode->i_sb);43 err = reiserfs_commit_for_inode(inode);44 reiserfs_write_unlock(inode->i_sb);45 inode_unlock(inode);46 if (err < 0)47 return err;48 return 0;49}50 51#define store_ih(where,what) copy_item_head (where, what)52 53static inline bool is_privroot_deh(struct inode *dir, struct reiserfs_de_head *deh)54{55 struct dentry *privroot = REISERFS_SB(dir->i_sb)->priv_root;56 return (d_really_is_positive(privroot) &&57 deh->deh_objectid == INODE_PKEY(d_inode(privroot))->k_objectid);58}59 60int reiserfs_readdir_inode(struct inode *inode, struct dir_context *ctx)61{62 63 /* key of current position in the directory (key of directory entry) */64 struct cpu_key pos_key;65 66 INITIALIZE_PATH(path_to_entry);67 struct buffer_head *bh;68 int item_num, entry_num;69 const struct reiserfs_key *rkey;70 struct item_head *ih, tmp_ih;71 int search_res;72 char *local_buf;73 loff_t next_pos;74 char small_buf[32]; /* avoid kmalloc if we can */75 struct reiserfs_dir_entry de;76 int ret = 0;77 int depth;78 79 reiserfs_write_lock(inode->i_sb);80 81 reiserfs_check_lock_depth(inode->i_sb, "readdir");82 83 /*84 * form key for search the next directory entry using85 * f_pos field of file structure86 */87 make_cpu_key(&pos_key, inode, ctx->pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);88 next_pos = cpu_key_k_offset(&pos_key);89 90 path_to_entry.reada = PATH_READA;91 while (1) {92research:93 /*94 * search the directory item, containing entry with95 * specified key96 */97 search_res =98 search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,99 &de);100 if (search_res == IO_ERROR) {101 /*102 * FIXME: we could just skip part of directory103 * which could not be read104 */105 ret = -EIO;106 goto out;107 }108 entry_num = de.de_entry_num;109 bh = de.de_bh;110 item_num = de.de_item_num;111 ih = de.de_ih;112 store_ih(&tmp_ih, ih);113 114 /* we must have found item, that is item of this directory, */115 RFALSE(COMP_SHORT_KEYS(&ih->ih_key, &pos_key),116 "vs-9000: found item %h does not match to dir we readdir %K",117 ih, &pos_key);118 RFALSE(item_num > B_NR_ITEMS(bh) - 1,119 "vs-9005 item_num == %d, item amount == %d",120 item_num, B_NR_ITEMS(bh));121 122 /*123 * and entry must be not more than number of entries124 * in the item125 */126 RFALSE(ih_entry_count(ih) < entry_num,127 "vs-9010: entry number is too big %d (%d)",128 entry_num, ih_entry_count(ih));129 130 /*131 * go through all entries in the directory item beginning132 * from the entry, that has been found133 */134 if (search_res == POSITION_FOUND135 || entry_num < ih_entry_count(ih)) {136 struct reiserfs_de_head *deh =137 B_I_DEH(bh, ih) + entry_num;138 139 for (; entry_num < ih_entry_count(ih);140 entry_num++, deh++) {141 int d_reclen;142 char *d_name;143 ino_t d_ino;144 loff_t cur_pos = deh_offset(deh);145 146 /* it is hidden entry */147 if (!de_visible(deh))148 continue;149 d_reclen = entry_length(bh, ih, entry_num);150 d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);151 152 if (d_reclen <= 0 ||153 d_name + d_reclen > bh->b_data + bh->b_size) {154 /*155 * There is corrupted data in entry,156 * We'd better stop here157 */158 pathrelse(&path_to_entry);159 ret = -EIO;160 goto out;161 }162 163 if (!d_name[d_reclen - 1])164 d_reclen = strlen(d_name);165 166 /* too big to send back to VFS */167 if (d_reclen >168 REISERFS_MAX_NAME(inode->i_sb->169 s_blocksize)) {170 continue;171 }172 173 /* Ignore the .reiserfs_priv entry */174 if (is_privroot_deh(inode, deh))175 continue;176 177 ctx->pos = deh_offset(deh);178 d_ino = deh_objectid(deh);179 if (d_reclen <= 32) {180 local_buf = small_buf;181 } else {182 local_buf = kmalloc(d_reclen,183 GFP_NOFS);184 if (!local_buf) {185 pathrelse(&path_to_entry);186 ret = -ENOMEM;187 goto out;188 }189 if (item_moved(&tmp_ih, &path_to_entry)) {190 kfree(local_buf);191 goto research;192 }193 }194 195 /*196 * Note, that we copy name to user space via197 * temporary buffer (local_buf) because198 * filldir will block if user space buffer is199 * swapped out. At that time entry can move to200 * somewhere else201 */202 memcpy(local_buf, d_name, d_reclen);203 204 /*205 * Since filldir might sleep, we can release206 * the write lock here for other waiters207 */208 depth = reiserfs_write_unlock_nested(inode->i_sb);209 if (!dir_emit210 (ctx, local_buf, d_reclen, d_ino,211 DT_UNKNOWN)) {212 reiserfs_write_lock_nested(inode->i_sb, depth);213 if (local_buf != small_buf) {214 kfree(local_buf);215 }216 goto end;217 }218 reiserfs_write_lock_nested(inode->i_sb, depth);219 if (local_buf != small_buf) {220 kfree(local_buf);221 }222 223 /* deh_offset(deh) may be invalid now. */224 next_pos = cur_pos + 1;225 226 if (item_moved(&tmp_ih, &path_to_entry)) {227 set_cpu_key_k_offset(&pos_key,228 next_pos);229 goto research;230 }231 } /* for */232 }233 234 /* end of directory has been reached */235 if (item_num != B_NR_ITEMS(bh) - 1)236 goto end;237 238 /*239 * item we went through is last item of node. Using right240 * delimiting key check is it directory end241 */242 rkey = get_rkey(&path_to_entry, inode->i_sb);243 if (!comp_le_keys(rkey, &MIN_KEY)) {244 /*245 * set pos_key to key, that is the smallest and greater246 * that key of the last entry in the item247 */248 set_cpu_key_k_offset(&pos_key, next_pos);249 continue;250 }251 252 /* end of directory has been reached */253 if (COMP_SHORT_KEYS(rkey, &pos_key)) {254 goto end;255 }256 257 /* directory continues in the right neighboring block */258 set_cpu_key_k_offset(&pos_key,259 le_key_k_offset(KEY_FORMAT_3_5, rkey));260 261 } /* while */262 263end:264 ctx->pos = next_pos;265 pathrelse(&path_to_entry);266 reiserfs_check_path(&path_to_entry);267out:268 reiserfs_write_unlock(inode->i_sb);269 return ret;270}271 272static int reiserfs_readdir(struct file *file, struct dir_context *ctx)273{274 return reiserfs_readdir_inode(file_inode(file), ctx);275}276 277/*278 * compose directory item containing "." and ".." entries (entries are279 * not aligned to 4 byte boundary)280 */281void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,282 __le32 par_dirid, __le32 par_objid)283{284 struct reiserfs_de_head *dot, *dotdot;285 286 memset(body, 0, EMPTY_DIR_SIZE_V1);287 dot = (struct reiserfs_de_head *)body;288 dotdot = dot + 1;289 290 /* direntry header of "." */291 put_deh_offset(dot, DOT_OFFSET);292 /* these two are from make_le_item_head, and are LE */293 dot->deh_dir_id = dirid;294 dot->deh_objectid = objid;295 dot->deh_state = 0; /* Endian safe if 0 */296 put_deh_location(dot, EMPTY_DIR_SIZE_V1 - strlen("."));297 mark_de_visible(dot);298 299 /* direntry header of ".." */300 put_deh_offset(dotdot, DOT_DOT_OFFSET);301 /* key of ".." for the root directory */302 /* these two are from the inode, and are LE */303 dotdot->deh_dir_id = par_dirid;304 dotdot->deh_objectid = par_objid;305 dotdot->deh_state = 0; /* Endian safe if 0 */306 put_deh_location(dotdot, deh_location(dot) - strlen(".."));307 mark_de_visible(dotdot);308 309 /* copy ".." and "." */310 memcpy(body + deh_location(dot), ".", 1);311 memcpy(body + deh_location(dotdot), "..", 2);312}313 314/* compose directory item containing "." and ".." entries */315void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,316 __le32 par_dirid, __le32 par_objid)317{318 struct reiserfs_de_head *dot, *dotdot;319 320 memset(body, 0, EMPTY_DIR_SIZE);321 dot = (struct reiserfs_de_head *)body;322 dotdot = dot + 1;323 324 /* direntry header of "." */325 put_deh_offset(dot, DOT_OFFSET);326 /* these two are from make_le_item_head, and are LE */327 dot->deh_dir_id = dirid;328 dot->deh_objectid = objid;329 dot->deh_state = 0; /* Endian safe if 0 */330 put_deh_location(dot, EMPTY_DIR_SIZE - ROUND_UP(strlen(".")));331 mark_de_visible(dot);332 333 /* direntry header of ".." */334 put_deh_offset(dotdot, DOT_DOT_OFFSET);335 /* key of ".." for the root directory */336 /* these two are from the inode, and are LE */337 dotdot->deh_dir_id = par_dirid;338 dotdot->deh_objectid = par_objid;339 dotdot->deh_state = 0; /* Endian safe if 0 */340 put_deh_location(dotdot, deh_location(dot) - ROUND_UP(strlen("..")));341 mark_de_visible(dotdot);342 343 /* copy ".." and "." */344 memcpy(body + deh_location(dot), ".", 1);345 memcpy(body + deh_location(dotdot), "..", 2);346}347