1 /* 2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README 3 */ 4 5 #include <linux/config.h> 6 #include <linux/string.h> 7 #include <linux/errno.h> 8 #include <linux/fs.h> 9 #include <linux/reiserfs_fs.h> 10 #include <linux/stat.h> 11 #include <linux/smp_lock.h> 12 #include <linux/buffer_head.h> 13 #include <asm/uaccess.h> 14 15 extern struct reiserfs_key MIN_KEY; 16 17 static int reiserfs_readdir (struct file *, void *, filldir_t); 18 static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry, int datasync) ; 19 20 struct file_operations reiserfs_dir_operations = { 21 .read = generic_read_dir, 22 .readdir = reiserfs_readdir, 23 .fsync = reiserfs_dir_fsync, 24 .ioctl = reiserfs_ioctl, 25 }; 26 27 static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry, int datasync) { 28 struct inode *inode = dentry->d_inode; 29 int err; 30 reiserfs_write_lock(inode->i_sb); 31 err = reiserfs_commit_for_inode(inode) ; 32 reiserfs_write_unlock(inode->i_sb) ; 33 if (err < 0) 34 return err; 35 return 0; 36 } 37 38 39 #define store_ih(where,what) copy_item_head (where, what) 40 41 // 42 static int reiserfs_readdir (struct file * filp, void * dirent, filldir_t filldir) 43 { 44 struct inode *inode = filp->f_dentry->d_inode; 45 struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */ 46 INITIALIZE_PATH (path_to_entry); 47 struct buffer_head * bh; 48 int item_num, entry_num; 49 const struct reiserfs_key * rkey; 50 struct item_head * ih, tmp_ih; 51 int search_res; 52 char * local_buf; 53 loff_t next_pos; 54 char small_buf[32] ; /* avoid kmalloc if we can */ 55 struct reiserfs_dir_entry de; 56 int ret = 0; 57 58 reiserfs_write_lock(inode->i_sb); 59 60 reiserfs_check_lock_depth(inode->i_sb, "readdir") ; 61 62 /* form key for search the next directory entry using f_pos field of 63 file structure */ 64 make_cpu_key (&pos_key, inode, (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET, 65 TYPE_DIRENTRY, 3); 66 next_pos = cpu_key_k_offset (&pos_key); 67 68 /* reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos);*/ 69 70 path_to_entry.reada = PATH_READA; 71 while (1) { 72 research: 73 /* search the directory item, containing entry with specified key */ 74 search_res = search_by_entry_key (inode->i_sb, &pos_key, &path_to_entry, &de); 75 if (search_res == IO_ERROR) { 76 // FIXME: we could just skip part of directory which could 77 // not be read 78 ret = -EIO; 79 goto out; 80 } 81 entry_num = de.de_entry_num; 82 bh = de.de_bh; 83 item_num = de.de_item_num; 84 ih = de.de_ih; 85 store_ih (&tmp_ih, ih); 86 87 /* we must have found item, that is item of this directory, */ 88 RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key), 89 "vs-9000: found item %h does not match to dir we readdir %K", 90 ih, &pos_key); 91 RFALSE( item_num > B_NR_ITEMS (bh) - 1, 92 "vs-9005 item_num == %d, item amount == %d", 93 item_num, B_NR_ITEMS (bh)); 94 95 /* and entry must be not more than number of entries in the item */ 96 RFALSE( I_ENTRY_COUNT (ih) < entry_num, 97 "vs-9010: entry number is too big %d (%d)", 98 entry_num, I_ENTRY_COUNT (ih)); 99 100 if (search_res == POSITION_FOUND || entry_num < I_ENTRY_COUNT (ih)) { 101 /* go through all entries in the directory item beginning from the entry, that has been found */ 102 struct reiserfs_de_head * deh = B_I_DEH (bh, ih) + entry_num; 103 104 for (; entry_num < I_ENTRY_COUNT (ih); entry_num ++, deh ++) { 105 int d_reclen; 106 char * d_name; 107 off_t d_off; 108 ino_t d_ino; 109 110 if (!de_visible (deh)) 111 /* it is hidden entry */ 112 continue; 113 d_reclen = entry_length (bh, ih, entry_num); 114 d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh); 115 if (!d_name[d_reclen - 1]) 116 d_reclen = strlen (d_name); 117 118 if (d_reclen > REISERFS_MAX_NAME(inode->i_sb->s_blocksize)){ 119 /* too big to send back to VFS */ 120 continue ; 121 } 122 123 /* Ignore the .reiserfs_priv entry */ 124 if (reiserfs_xattrs (inode->i_sb) && 125 !old_format_only(inode->i_sb) && 126 filp->f_dentry == inode->i_sb->s_root && 127 REISERFS_SB(inode->i_sb)->priv_root && 128 REISERFS_SB(inode->i_sb)->priv_root->d_inode && 129 deh_objectid(deh) == le32_to_cpu (INODE_PKEY(REISERFS_SB(inode->i_sb)->priv_root->d_inode)->k_objectid)) { 130 continue; 131 } 132 133 d_off = deh_offset (deh); 134 filp->f_pos = d_off ; 135 d_ino = deh_objectid (deh); 136 if (d_reclen <= 32) { 137 local_buf = small_buf ; 138 } else { 139 local_buf = reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb) ; 140 if (!local_buf) { 141 pathrelse (&path_to_entry); 142 ret = -ENOMEM ; 143 goto out; 144 } 145 if (item_moved (&tmp_ih, &path_to_entry)) { 146 reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ; 147 goto research; 148 } 149 } 150 // Note, that we copy name to user space via temporary 151 // buffer (local_buf) because filldir will block if 152 // user space buffer is swapped out. At that time 153 // entry can move to somewhere else 154 memcpy (local_buf, d_name, d_reclen); 155 if (filldir (dirent, local_buf, d_reclen, d_off, d_ino, 156 DT_UNKNOWN) < 0) { 157 if (local_buf != small_buf) { 158 reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ; 159 } 160 goto end; 161 } 162 if (local_buf != small_buf) { 163 reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ; 164 } 165 166 // next entry should be looked for with such offset 167 next_pos = deh_offset (deh) + 1; 168 169 if (item_moved (&tmp_ih, &path_to_entry)) { 170 goto research; 171 } 172 } /* for */ 173 } 174 175 if (item_num != B_NR_ITEMS (bh) - 1) 176 // end of directory has been reached 177 goto end; 178 179 /* item we went through is last item of node. Using right 180 delimiting key check is it directory end */ 181 rkey = get_rkey (&path_to_entry, inode->i_sb); 182 if (! comp_le_keys (rkey, &MIN_KEY)) { 183 /* set pos_key to key, that is the smallest and greater 184 that key of the last entry in the item */ 185 set_cpu_key_k_offset (&pos_key, next_pos); 186 continue; 187 } 188 189 if ( COMP_SHORT_KEYS (rkey, &pos_key)) { 190 // end of directory has been reached 191 goto end; 192 } 193 194 /* directory continues in the right neighboring block */ 195 set_cpu_key_k_offset (&pos_key, le_key_k_offset (KEY_FORMAT_3_5, rkey)); 196 197 } /* while */ 198 199 200 end: 201 filp->f_pos = next_pos; 202 pathrelse (&path_to_entry); 203 reiserfs_check_path(&path_to_entry) ; 204 out: 205 reiserfs_write_unlock(inode->i_sb); 206 return ret; 207 } 208 209 /* compose directory item containing "." and ".." entries (entries are 210 not aligned to 4 byte boundary) */ 211 /* the last four params are LE */ 212 void make_empty_dir_item_v1 (char * body, __u32 dirid, __u32 objid, 213 __u32 par_dirid, __u32 par_objid) 214 { 215 struct reiserfs_de_head * deh; 216 217 memset (body, 0, EMPTY_DIR_SIZE_V1); 218 deh = (struct reiserfs_de_head *)body; 219 220 /* direntry header of "." */ 221 put_deh_offset( &(deh[0]), DOT_OFFSET ); 222 /* these two are from make_le_item_head, and are are LE */ 223 deh[0].deh_dir_id = dirid; 224 deh[0].deh_objectid = objid; 225 deh[0].deh_state = 0; /* Endian safe if 0 */ 226 put_deh_location( &(deh[0]), EMPTY_DIR_SIZE_V1 - strlen( "." )); 227 mark_de_visible(&(deh[0])); 228 229 /* direntry header of ".." */ 230 put_deh_offset( &(deh[1]), DOT_DOT_OFFSET); 231 /* key of ".." for the root directory */ 232 /* these two are from the inode, and are are LE */ 233 deh[1].deh_dir_id = par_dirid; 234 deh[1].deh_objectid = par_objid; 235 deh[1].deh_state = 0; /* Endian safe if 0 */ 236 put_deh_location( &(deh[1]), deh_location( &(deh[0]) ) - strlen( ".." ) ); 237 mark_de_visible(&(deh[1])); 238 239 /* copy ".." and "." */ 240 memcpy (body + deh_location( &(deh[0]) ), ".", 1); 241 memcpy (body + deh_location( &(deh[1]) ), "..", 2); 242 } 243 244 /* compose directory item containing "." and ".." entries */ 245 void make_empty_dir_item (char * body, __u32 dirid, __u32 objid, 246 __u32 par_dirid, __u32 par_objid) 247 { 248 struct reiserfs_de_head * deh; 249 250 memset (body, 0, EMPTY_DIR_SIZE); 251 deh = (struct reiserfs_de_head *)body; 252 253 /* direntry header of "." */ 254 put_deh_offset( &(deh[0]), DOT_OFFSET ); 255 /* these two are from make_le_item_head, and are are LE */ 256 deh[0].deh_dir_id = dirid; 257 deh[0].deh_objectid = objid; 258 deh[0].deh_state = 0; /* Endian safe if 0 */ 259 put_deh_location( &(deh[0]), EMPTY_DIR_SIZE - ROUND_UP( strlen( "." ) ) ); 260 mark_de_visible(&(deh[0])); 261 262 /* direntry header of ".." */ 263 put_deh_offset( &(deh[1]), DOT_DOT_OFFSET ); 264 /* key of ".." for the root directory */ 265 /* these two are from the inode, and are are LE */ 266 deh[1].deh_dir_id = par_dirid; 267 deh[1].deh_objectid = par_objid; 268 deh[1].deh_state = 0; /* Endian safe if 0 */ 269 put_deh_location( &(deh[1]), deh_location( &(deh[0])) - ROUND_UP( strlen( ".." ) ) ); 270 mark_de_visible(&(deh[1])); 271 272 /* copy ".." and "." */ 273 memcpy (body + deh_location( &(deh[0]) ), ".", 1); 274 memcpy (body + deh_location( &(deh[1]) ), "..", 2); 275 } 276