Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/ext3/dir.c |
| 3 | * |
| 4 | * Copyright (C) 1992, 1993, 1994, 1995 |
| 5 | * Remy Card (card@masi.ibp.fr) |
| 6 | * Laboratoire MASI - Institut Blaise Pascal |
| 7 | * Universite Pierre et Marie Curie (Paris VI) |
| 8 | * |
| 9 | * from |
| 10 | * |
| 11 | * linux/fs/minix/dir.c |
| 12 | * |
| 13 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 14 | * |
| 15 | * ext3 directory handling functions |
| 16 | * |
| 17 | * Big-endian to little-endian byte-swapping/bitmaps by |
| 18 | * David S. Miller (davem@caip.rutgers.edu), 1995 |
| 19 | * |
| 20 | * Hash Tree Directory indexing (c) 2001 Daniel Phillips |
| 21 | * |
| 22 | */ |
| 23 | |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 24 | #include <linux/compat.h> |
Al Viro | 4613ad1 | 2012-03-29 22:30:07 -0400 | [diff] [blame] | 25 | #include "ext3.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
| 27 | static unsigned char ext3_filetype_table[] = { |
| 28 | DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK |
| 29 | }; |
| 30 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | static int ext3_dx_readdir(struct file * filp, |
| 32 | void * dirent, filldir_t filldir); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | |
| 34 | static unsigned char get_dtype(struct super_block *sb, int filetype) |
| 35 | { |
| 36 | if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE) || |
| 37 | (filetype >= EXT3_FT_MAX)) |
| 38 | return DT_UNKNOWN; |
| 39 | |
| 40 | return (ext3_filetype_table[filetype]); |
| 41 | } |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 42 | |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 43 | /** |
| 44 | * Check if the given dir-inode refers to an htree-indexed directory |
| 45 | * (or a directory which chould potentially get coverted to use htree |
| 46 | * indexing). |
| 47 | * |
| 48 | * Return 1 if it is a dx dir, 0 if not |
| 49 | */ |
| 50 | static int is_dx_dir(struct inode *inode) |
| 51 | { |
| 52 | struct super_block *sb = inode->i_sb; |
| 53 | |
| 54 | if (EXT3_HAS_COMPAT_FEATURE(inode->i_sb, |
| 55 | EXT3_FEATURE_COMPAT_DIR_INDEX) && |
| 56 | ((EXT3_I(inode)->i_flags & EXT3_INDEX_FL) || |
| 57 | ((inode->i_size >> sb->s_blocksize_bits) == 1))) |
| 58 | return 1; |
| 59 | |
| 60 | return 0; |
| 61 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | |
| 63 | int ext3_check_dir_entry (const char * function, struct inode * dir, |
| 64 | struct ext3_dir_entry_2 * de, |
| 65 | struct buffer_head * bh, |
| 66 | unsigned long offset) |
| 67 | { |
| 68 | const char * error_msg = NULL; |
Jan Kara | 7c06a8d | 2007-11-14 17:00:19 -0800 | [diff] [blame] | 69 | const int rlen = ext3_rec_len_from_disk(de->rec_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | |
Eric Sandeen | a4ae309 | 2010-12-07 11:55:27 -0600 | [diff] [blame] | 71 | if (unlikely(rlen < EXT3_DIR_REC_LEN(1))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | error_msg = "rec_len is smaller than minimal"; |
Eric Sandeen | a4ae309 | 2010-12-07 11:55:27 -0600 | [diff] [blame] | 73 | else if (unlikely(rlen % 4 != 0)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | error_msg = "rec_len % 4 != 0"; |
Eric Sandeen | a4ae309 | 2010-12-07 11:55:27 -0600 | [diff] [blame] | 75 | else if (unlikely(rlen < EXT3_DIR_REC_LEN(de->name_len))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | error_msg = "rec_len is too small for name_len"; |
Eric Sandeen | a4ae309 | 2010-12-07 11:55:27 -0600 | [diff] [blame] | 77 | else if (unlikely((((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | error_msg = "directory entry across blocks"; |
Eric Sandeen | a4ae309 | 2010-12-07 11:55:27 -0600 | [diff] [blame] | 79 | else if (unlikely(le32_to_cpu(de->inode) > |
| 80 | le32_to_cpu(EXT3_SB(dir->i_sb)->s_es->s_inodes_count))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | error_msg = "inode out of bounds"; |
| 82 | |
Eric Sandeen | a4ae309 | 2010-12-07 11:55:27 -0600 | [diff] [blame] | 83 | if (unlikely(error_msg != NULL)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | ext3_error (dir->i_sb, function, |
| 85 | "bad entry in directory #%lu: %s - " |
| 86 | "offset=%lu, inode=%lu, rec_len=%d, name_len=%d", |
| 87 | dir->i_ino, error_msg, offset, |
| 88 | (unsigned long) le32_to_cpu(de->inode), |
| 89 | rlen, de->name_len); |
Eric Sandeen | a4ae309 | 2010-12-07 11:55:27 -0600 | [diff] [blame] | 90 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | return error_msg == NULL ? 1 : 0; |
| 92 | } |
| 93 | |
| 94 | static int ext3_readdir(struct file * filp, |
| 95 | void * dirent, filldir_t filldir) |
| 96 | { |
| 97 | int error = 0; |
Andrew Morton | d8733c2 | 2006-03-23 03:00:11 -0800 | [diff] [blame] | 98 | unsigned long offset; |
| 99 | int i, stored; |
| 100 | struct ext3_dir_entry_2 *de; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | int err; |
Josef "Jeff" Sipek | fe21a69 | 2006-12-08 02:36:38 -0800 | [diff] [blame] | 102 | struct inode *inode = filp->f_path.dentry->d_inode; |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 103 | struct super_block *sb = inode->i_sb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | int ret = 0; |
Eric Sandeen | cdbf6db | 2008-10-18 20:28:00 -0700 | [diff] [blame] | 105 | int dir_has_error = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 107 | if (is_dx_dir(inode)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | err = ext3_dx_readdir(filp, dirent, filldir); |
| 109 | if (err != ERR_BAD_DX_DIR) { |
| 110 | ret = err; |
| 111 | goto out; |
| 112 | } |
| 113 | /* |
| 114 | * We don't set the inode dirty flag since it's not |
| 115 | * critical that it get flushed back to the disk. |
| 116 | */ |
Josef "Jeff" Sipek | fe21a69 | 2006-12-08 02:36:38 -0800 | [diff] [blame] | 117 | EXT3_I(filp->f_path.dentry->d_inode)->i_flags &= ~EXT3_INDEX_FL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | stored = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | offset = filp->f_pos & (sb->s_blocksize - 1); |
| 121 | |
| 122 | while (!error && !stored && filp->f_pos < inode->i_size) { |
Andrew Morton | d8733c2 | 2006-03-23 03:00:11 -0800 | [diff] [blame] | 123 | unsigned long blk = filp->f_pos >> EXT3_BLOCK_SIZE_BITS(sb); |
| 124 | struct buffer_head map_bh; |
| 125 | struct buffer_head *bh = NULL; |
| 126 | |
| 127 | map_bh.b_state = 0; |
Jan Kara | 43237b5 | 2009-05-20 18:41:58 +0200 | [diff] [blame] | 128 | err = ext3_get_blocks_handle(NULL, inode, blk, 1, &map_bh, 0); |
Mingming Cao | 89747d3 | 2006-03-26 01:37:55 -0800 | [diff] [blame] | 129 | if (err > 0) { |
Fengguang Wu | dc7868f | 2007-07-19 01:48:04 -0700 | [diff] [blame] | 130 | pgoff_t index = map_bh.b_blocknr >> |
| 131 | (PAGE_CACHE_SHIFT - inode->i_blkbits); |
| 132 | if (!ra_has_index(&filp->f_ra, index)) |
Rusty Russell | cf914a7 | 2007-07-19 01:48:08 -0700 | [diff] [blame] | 133 | page_cache_sync_readahead( |
Fengguang Wu | dc7868f | 2007-07-19 01:48:04 -0700 | [diff] [blame] | 134 | sb->s_bdev->bd_inode->i_mapping, |
| 135 | &filp->f_ra, filp, |
Rusty Russell | cf914a7 | 2007-07-19 01:48:08 -0700 | [diff] [blame] | 136 | index, 1); |
Fengguang Wu | f4e6b49 | 2007-10-16 01:24:33 -0700 | [diff] [blame] | 137 | filp->f_ra.prev_pos = (loff_t)index << PAGE_CACHE_SHIFT; |
Andrew Morton | d8733c2 | 2006-03-23 03:00:11 -0800 | [diff] [blame] | 138 | bh = ext3_bread(NULL, inode, blk, 0, &err); |
| 139 | } |
| 140 | |
| 141 | /* |
| 142 | * We ignore I/O errors on directories so users have a chance |
| 143 | * of recovering data when there's a bad sector |
| 144 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | if (!bh) { |
Eric Sandeen | cdbf6db | 2008-10-18 20:28:00 -0700 | [diff] [blame] | 146 | if (!dir_has_error) { |
| 147 | ext3_error(sb, __func__, "directory #%lu " |
| 148 | "contains a hole at offset %lld", |
| 149 | inode->i_ino, filp->f_pos); |
| 150 | dir_has_error = 1; |
| 151 | } |
Eric Sandeen | 40b8513 | 2006-12-06 20:36:26 -0800 | [diff] [blame] | 152 | /* corrupt size? Maybe no more blocks to read */ |
| 153 | if (filp->f_pos > inode->i_blocks << 9) |
| 154 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | filp->f_pos += sb->s_blocksize - offset; |
| 156 | continue; |
| 157 | } |
| 158 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | revalidate: |
| 160 | /* If the dir block has changed since the last call to |
| 161 | * readdir(2), then we might be pointing to an invalid |
| 162 | * dirent right now. Scan from the start of the block |
| 163 | * to make sure. */ |
| 164 | if (filp->f_version != inode->i_version) { |
| 165 | for (i = 0; i < sb->s_blocksize && i < offset; ) { |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 166 | de = (struct ext3_dir_entry_2 *) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | (bh->b_data + i); |
| 168 | /* It's too expensive to do a full |
| 169 | * dirent test each time round this |
| 170 | * loop, but we do have to test at |
| 171 | * least that it is non-zero. A |
| 172 | * failure will be detected in the |
| 173 | * dirent test below. */ |
Jan Kara | 7c06a8d | 2007-11-14 17:00:19 -0800 | [diff] [blame] | 174 | if (ext3_rec_len_from_disk(de->rec_len) < |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | EXT3_DIR_REC_LEN(1)) |
| 176 | break; |
Jan Kara | 7c06a8d | 2007-11-14 17:00:19 -0800 | [diff] [blame] | 177 | i += ext3_rec_len_from_disk(de->rec_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | } |
| 179 | offset = i; |
| 180 | filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1)) |
| 181 | | offset; |
| 182 | filp->f_version = inode->i_version; |
| 183 | } |
| 184 | |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 185 | while (!error && filp->f_pos < inode->i_size |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 186 | && offset < sb->s_blocksize) { |
| 187 | de = (struct ext3_dir_entry_2 *) (bh->b_data + offset); |
| 188 | if (!ext3_check_dir_entry ("ext3_readdir", inode, de, |
| 189 | bh, offset)) { |
| 190 | /* On error, skip the f_pos to the |
| 191 | next block. */ |
| 192 | filp->f_pos = (filp->f_pos | |
| 193 | (sb->s_blocksize - 1)) + 1; |
| 194 | brelse (bh); |
| 195 | ret = stored; |
| 196 | goto out; |
| 197 | } |
Jan Kara | 7c06a8d | 2007-11-14 17:00:19 -0800 | [diff] [blame] | 198 | offset += ext3_rec_len_from_disk(de->rec_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | if (le32_to_cpu(de->inode)) { |
| 200 | /* We might block in the next section |
| 201 | * if the data destination is |
| 202 | * currently swapped out. So, use a |
| 203 | * version stamp to detect whether or |
| 204 | * not the directory has been modified |
| 205 | * during the copy operation. |
| 206 | */ |
Mathieu Desnoyers | 2b47c36 | 2007-10-16 23:27:21 -0700 | [diff] [blame] | 207 | u64 version = filp->f_version; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | |
| 209 | error = filldir(dirent, de->name, |
| 210 | de->name_len, |
| 211 | filp->f_pos, |
| 212 | le32_to_cpu(de->inode), |
| 213 | get_dtype(sb, de->file_type)); |
| 214 | if (error) |
| 215 | break; |
| 216 | if (version != filp->f_version) |
| 217 | goto revalidate; |
| 218 | stored ++; |
| 219 | } |
Jan Kara | 7c06a8d | 2007-11-14 17:00:19 -0800 | [diff] [blame] | 220 | filp->f_pos += ext3_rec_len_from_disk(de->rec_len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | } |
| 222 | offset = 0; |
| 223 | brelse (bh); |
| 224 | } |
| 225 | out: |
| 226 | return ret; |
| 227 | } |
| 228 | |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 229 | static inline int is_32bit_api(void) |
| 230 | { |
| 231 | #ifdef CONFIG_COMPAT |
| 232 | return is_compat_task(); |
| 233 | #else |
| 234 | return (BITS_PER_LONG == 32); |
| 235 | #endif |
| 236 | } |
| 237 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | /* |
| 239 | * These functions convert from the major/minor hash to an f_pos |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 240 | * value for dx directories |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 241 | * |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 242 | * Upper layer (for example NFS) should specify FMODE_32BITHASH or |
| 243 | * FMODE_64BITHASH explicitly. On the other hand, we allow ext3 to be mounted |
| 244 | * directly on both 32-bit and 64-bit nodes, under such case, neither |
| 245 | * FMODE_32BITHASH nor FMODE_64BITHASH is specified. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | */ |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 247 | static inline loff_t hash2pos(struct file *filp, __u32 major, __u32 minor) |
| 248 | { |
| 249 | if ((filp->f_mode & FMODE_32BITHASH) || |
| 250 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) |
| 251 | return major >> 1; |
| 252 | else |
| 253 | return ((__u64)(major >> 1) << 32) | (__u64)minor; |
| 254 | } |
| 255 | |
| 256 | static inline __u32 pos2maj_hash(struct file *filp, loff_t pos) |
| 257 | { |
| 258 | if ((filp->f_mode & FMODE_32BITHASH) || |
| 259 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) |
| 260 | return (pos << 1) & 0xffffffff; |
| 261 | else |
| 262 | return ((pos >> 32) << 1) & 0xffffffff; |
| 263 | } |
| 264 | |
| 265 | static inline __u32 pos2min_hash(struct file *filp, loff_t pos) |
| 266 | { |
| 267 | if ((filp->f_mode & FMODE_32BITHASH) || |
| 268 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) |
| 269 | return 0; |
| 270 | else |
| 271 | return pos & 0xffffffff; |
| 272 | } |
| 273 | |
| 274 | /* |
| 275 | * Return 32- or 64-bit end-of-file for dx directories |
| 276 | */ |
| 277 | static inline loff_t ext3_get_htree_eof(struct file *filp) |
| 278 | { |
| 279 | if ((filp->f_mode & FMODE_32BITHASH) || |
| 280 | (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api())) |
| 281 | return EXT3_HTREE_EOF_32BIT; |
| 282 | else |
| 283 | return EXT3_HTREE_EOF_64BIT; |
| 284 | } |
| 285 | |
| 286 | |
| 287 | /* |
| 288 | * ext3_dir_llseek() calls generic_file_llseek[_size]() to handle both |
| 289 | * non-htree and htree directories, where the "offset" is in terms |
| 290 | * of the filename hash value instead of the byte offset. |
| 291 | * |
| 292 | * Because we may return a 64-bit hash that is well beyond s_maxbytes, |
| 293 | * we need to pass the max hash as the maximum allowable offset in |
| 294 | * the htree directory case. |
| 295 | * |
| 296 | * NOTE: offsets obtained *before* ext3_set_inode_flag(dir, EXT3_INODE_INDEX) |
| 297 | * will be invalid once the directory was converted into a dx directory |
| 298 | */ |
| 299 | loff_t ext3_dir_llseek(struct file *file, loff_t offset, int origin) |
| 300 | { |
| 301 | struct inode *inode = file->f_mapping->host; |
| 302 | int dx_dir = is_dx_dir(inode); |
Eric Sandeen | de9b942 | 2012-04-30 13:16:04 -0500 | [diff] [blame] | 303 | loff_t htree_max = ext3_get_htree_eof(file); |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 304 | |
| 305 | if (likely(dx_dir)) |
| 306 | return generic_file_llseek_size(file, offset, origin, |
Eric Sandeen | de9b942 | 2012-04-30 13:16:04 -0500 | [diff] [blame] | 307 | htree_max, htree_max); |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 308 | else |
| 309 | return generic_file_llseek(file, offset, origin); |
| 310 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | |
| 312 | /* |
| 313 | * This structure holds the nodes of the red-black tree used to store |
| 314 | * the directory entry in hash order. |
| 315 | */ |
| 316 | struct fname { |
| 317 | __u32 hash; |
| 318 | __u32 minor_hash; |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 319 | struct rb_node rb_hash; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | struct fname *next; |
| 321 | __u32 inode; |
| 322 | __u8 name_len; |
| 323 | __u8 file_type; |
| 324 | char name[0]; |
| 325 | }; |
| 326 | |
| 327 | /* |
| 328 | * This functoin implements a non-recursive way of freeing all of the |
| 329 | * nodes in the red-black tree. |
| 330 | */ |
| 331 | static void free_rb_tree_fname(struct rb_root *root) |
| 332 | { |
| 333 | struct rb_node *n = root->rb_node; |
| 334 | struct rb_node *parent; |
| 335 | struct fname *fname; |
| 336 | |
| 337 | while (n) { |
| 338 | /* Do the node's children first */ |
Shen Feng | 9ebfbe9 | 2008-07-25 01:46:21 -0700 | [diff] [blame] | 339 | if (n->rb_left) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | n = n->rb_left; |
| 341 | continue; |
| 342 | } |
| 343 | if (n->rb_right) { |
| 344 | n = n->rb_right; |
| 345 | continue; |
| 346 | } |
| 347 | /* |
| 348 | * The node has no children; free it, and then zero |
| 349 | * out parent's link to it. Finally go to the |
| 350 | * beginning of the loop and try to free the parent |
| 351 | * node. |
| 352 | */ |
David Woodhouse | 52b5108 | 2006-04-21 13:15:57 +0100 | [diff] [blame] | 353 | parent = rb_parent(n); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | fname = rb_entry(n, struct fname, rb_hash); |
| 355 | while (fname) { |
| 356 | struct fname * old = fname; |
| 357 | fname = fname->next; |
| 358 | kfree (old); |
| 359 | } |
| 360 | if (!parent) |
Venkatesh Pallipadi | 1513b02 | 2010-05-25 16:03:04 +0200 | [diff] [blame] | 361 | *root = RB_ROOT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | else if (parent->rb_left == n) |
| 363 | parent->rb_left = NULL; |
| 364 | else if (parent->rb_right == n) |
| 365 | parent->rb_right = NULL; |
| 366 | n = parent; |
| 367 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | } |
| 369 | |
| 370 | |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 371 | static struct dir_private_info *ext3_htree_create_dir_info(struct file *filp, |
| 372 | loff_t pos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | { |
| 374 | struct dir_private_info *p; |
| 375 | |
Shen Feng | 9ebfbe9 | 2008-07-25 01:46:21 -0700 | [diff] [blame] | 376 | p = kzalloc(sizeof(struct dir_private_info), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | if (!p) |
| 378 | return NULL; |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 379 | p->curr_hash = pos2maj_hash(filp, pos); |
| 380 | p->curr_minor_hash = pos2min_hash(filp, pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 381 | return p; |
| 382 | } |
| 383 | |
| 384 | void ext3_htree_free_dir_info(struct dir_private_info *p) |
| 385 | { |
| 386 | free_rb_tree_fname(&p->root); |
| 387 | kfree(p); |
| 388 | } |
| 389 | |
| 390 | /* |
| 391 | * Given a directory entry, enter it into the fname rb tree. |
| 392 | */ |
| 393 | int ext3_htree_store_dirent(struct file *dir_file, __u32 hash, |
| 394 | __u32 minor_hash, |
| 395 | struct ext3_dir_entry_2 *dirent) |
| 396 | { |
| 397 | struct rb_node **p, *parent = NULL; |
| 398 | struct fname * fname, *new_fn; |
| 399 | struct dir_private_info *info; |
| 400 | int len; |
| 401 | |
| 402 | info = (struct dir_private_info *) dir_file->private_data; |
| 403 | p = &info->root.rb_node; |
| 404 | |
| 405 | /* Create and allocate the fname structure */ |
| 406 | len = sizeof(struct fname) + dirent->name_len + 1; |
Panagiotis Issaris | f8314dc | 2006-09-27 01:49:37 -0700 | [diff] [blame] | 407 | new_fn = kzalloc(len, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | if (!new_fn) |
| 409 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | new_fn->hash = hash; |
| 411 | new_fn->minor_hash = minor_hash; |
| 412 | new_fn->inode = le32_to_cpu(dirent->inode); |
| 413 | new_fn->name_len = dirent->name_len; |
| 414 | new_fn->file_type = dirent->file_type; |
| 415 | memcpy(new_fn->name, dirent->name, dirent->name_len); |
| 416 | new_fn->name[dirent->name_len] = 0; |
| 417 | |
| 418 | while (*p) { |
| 419 | parent = *p; |
| 420 | fname = rb_entry(parent, struct fname, rb_hash); |
| 421 | |
| 422 | /* |
| 423 | * If the hash and minor hash match up, then we put |
| 424 | * them on a linked list. This rarely happens... |
| 425 | */ |
| 426 | if ((new_fn->hash == fname->hash) && |
| 427 | (new_fn->minor_hash == fname->minor_hash)) { |
| 428 | new_fn->next = fname->next; |
| 429 | fname->next = new_fn; |
| 430 | return 0; |
| 431 | } |
| 432 | |
| 433 | if (new_fn->hash < fname->hash) |
| 434 | p = &(*p)->rb_left; |
| 435 | else if (new_fn->hash > fname->hash) |
| 436 | p = &(*p)->rb_right; |
| 437 | else if (new_fn->minor_hash < fname->minor_hash) |
| 438 | p = &(*p)->rb_left; |
| 439 | else /* if (new_fn->minor_hash > fname->minor_hash) */ |
| 440 | p = &(*p)->rb_right; |
| 441 | } |
| 442 | |
| 443 | rb_link_node(&new_fn->rb_hash, parent, p); |
| 444 | rb_insert_color(&new_fn->rb_hash, &info->root); |
| 445 | return 0; |
| 446 | } |
| 447 | |
| 448 | |
| 449 | |
| 450 | /* |
| 451 | * This is a helper function for ext3_dx_readdir. It calls filldir |
| 452 | * for all entres on the fname linked list. (Normally there is only |
| 453 | * one entry on the linked list, unless there are 62 bit hash collisions.) |
| 454 | */ |
| 455 | static int call_filldir(struct file * filp, void * dirent, |
| 456 | filldir_t filldir, struct fname *fname) |
| 457 | { |
| 458 | struct dir_private_info *info = filp->private_data; |
| 459 | loff_t curr_pos; |
Josef "Jeff" Sipek | fe21a69 | 2006-12-08 02:36:38 -0800 | [diff] [blame] | 460 | struct inode *inode = filp->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | struct super_block * sb; |
| 462 | int error; |
| 463 | |
| 464 | sb = inode->i_sb; |
| 465 | |
| 466 | if (!fname) { |
| 467 | printk("call_filldir: called with null fname?!?\n"); |
| 468 | return 0; |
| 469 | } |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 470 | curr_pos = hash2pos(filp, fname->hash, fname->minor_hash); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | while (fname) { |
| 472 | error = filldir(dirent, fname->name, |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 473 | fname->name_len, curr_pos, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | fname->inode, |
| 475 | get_dtype(sb, fname->file_type)); |
| 476 | if (error) { |
| 477 | filp->f_pos = curr_pos; |
Eugene Dashevsky | 6a897cf | 2008-10-18 20:27:59 -0700 | [diff] [blame] | 478 | info->extra_fname = fname; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | return error; |
| 480 | } |
| 481 | fname = fname->next; |
| 482 | } |
| 483 | return 0; |
| 484 | } |
| 485 | |
| 486 | static int ext3_dx_readdir(struct file * filp, |
| 487 | void * dirent, filldir_t filldir) |
| 488 | { |
| 489 | struct dir_private_info *info = filp->private_data; |
Josef "Jeff" Sipek | fe21a69 | 2006-12-08 02:36:38 -0800 | [diff] [blame] | 490 | struct inode *inode = filp->f_path.dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | struct fname *fname; |
| 492 | int ret; |
| 493 | |
| 494 | if (!info) { |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 495 | info = ext3_htree_create_dir_info(filp, filp->f_pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | if (!info) |
| 497 | return -ENOMEM; |
| 498 | filp->private_data = info; |
| 499 | } |
| 500 | |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 501 | if (filp->f_pos == ext3_get_htree_eof(filp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | return 0; /* EOF */ |
| 503 | |
| 504 | /* Some one has messed with f_pos; reset the world */ |
| 505 | if (info->last_pos != filp->f_pos) { |
| 506 | free_rb_tree_fname(&info->root); |
| 507 | info->curr_node = NULL; |
| 508 | info->extra_fname = NULL; |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 509 | info->curr_hash = pos2maj_hash(filp, filp->f_pos); |
| 510 | info->curr_minor_hash = pos2min_hash(filp, filp->f_pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | } |
| 512 | |
| 513 | /* |
| 514 | * If there are any leftover names on the hash collision |
| 515 | * chain, return them first. |
| 516 | */ |
Eugene Dashevsky | 6a897cf | 2008-10-18 20:27:59 -0700 | [diff] [blame] | 517 | if (info->extra_fname) { |
| 518 | if (call_filldir(filp, dirent, filldir, info->extra_fname)) |
| 519 | goto finished; |
Eugene Dashevsky | 6a897cf | 2008-10-18 20:27:59 -0700 | [diff] [blame] | 520 | info->extra_fname = NULL; |
Theodore Ts'o | 8c9fa93 | 2008-10-25 11:38:37 -0400 | [diff] [blame] | 521 | goto next_node; |
Eugene Dashevsky | 6a897cf | 2008-10-18 20:27:59 -0700 | [diff] [blame] | 522 | } else if (!info->curr_node) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | info->curr_node = rb_first(&info->root); |
| 524 | |
| 525 | while (1) { |
| 526 | /* |
| 527 | * Fill the rbtree if we have no more entries, |
| 528 | * or the inode has changed since we last read in the |
Mingming Cao | ae6ddcc | 2006-09-27 01:49:27 -0700 | [diff] [blame] | 529 | * cached entries. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 530 | */ |
| 531 | if ((!info->curr_node) || |
| 532 | (filp->f_version != inode->i_version)) { |
| 533 | info->curr_node = NULL; |
| 534 | free_rb_tree_fname(&info->root); |
| 535 | filp->f_version = inode->i_version; |
| 536 | ret = ext3_htree_fill_tree(filp, info->curr_hash, |
| 537 | info->curr_minor_hash, |
| 538 | &info->next_hash); |
| 539 | if (ret < 0) |
| 540 | return ret; |
| 541 | if (ret == 0) { |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 542 | filp->f_pos = ext3_get_htree_eof(filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 543 | break; |
| 544 | } |
| 545 | info->curr_node = rb_first(&info->root); |
| 546 | } |
| 547 | |
| 548 | fname = rb_entry(info->curr_node, struct fname, rb_hash); |
| 549 | info->curr_hash = fname->hash; |
| 550 | info->curr_minor_hash = fname->minor_hash; |
| 551 | if (call_filldir(filp, dirent, filldir, fname)) |
| 552 | break; |
Theodore Ts'o | 8c9fa93 | 2008-10-25 11:38:37 -0400 | [diff] [blame] | 553 | next_node: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | info->curr_node = rb_next(info->curr_node); |
Theodore Ts'o | 8c9fa93 | 2008-10-25 11:38:37 -0400 | [diff] [blame] | 555 | if (info->curr_node) { |
| 556 | fname = rb_entry(info->curr_node, struct fname, |
| 557 | rb_hash); |
| 558 | info->curr_hash = fname->hash; |
| 559 | info->curr_minor_hash = fname->minor_hash; |
| 560 | } else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | if (info->next_hash == ~0) { |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 562 | filp->f_pos = ext3_get_htree_eof(filp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | break; |
| 564 | } |
| 565 | info->curr_hash = info->next_hash; |
| 566 | info->curr_minor_hash = 0; |
| 567 | } |
| 568 | } |
| 569 | finished: |
| 570 | info->last_pos = filp->f_pos; |
| 571 | return 0; |
| 572 | } |
| 573 | |
| 574 | static int ext3_release_dir (struct inode * inode, struct file * filp) |
| 575 | { |
| 576 | if (filp->private_data) |
| 577 | ext3_htree_free_dir_info(filp->private_data); |
| 578 | |
| 579 | return 0; |
| 580 | } |
Eric Sandeen | d7dab39 | 2012-04-26 13:10:39 -0500 | [diff] [blame] | 581 | |
| 582 | const struct file_operations ext3_dir_operations = { |
| 583 | .llseek = ext3_dir_llseek, |
| 584 | .read = generic_read_dir, |
| 585 | .readdir = ext3_readdir, |
| 586 | .unlocked_ioctl = ext3_ioctl, |
| 587 | #ifdef CONFIG_COMPAT |
| 588 | .compat_ioctl = ext3_compat_ioctl, |
| 589 | #endif |
| 590 | .fsync = ext3_sync_file, |
| 591 | .release = ext3_release_dir, |
| 592 | }; |