1ac27a0ecSDave Kleikamp /* 2617ba13bSMingming Cao * linux/fs/ext4/dir.c 3ac27a0ecSDave Kleikamp * 4ac27a0ecSDave Kleikamp * Copyright (C) 1992, 1993, 1994, 1995 5ac27a0ecSDave Kleikamp * Remy Card (card@masi.ibp.fr) 6ac27a0ecSDave Kleikamp * Laboratoire MASI - Institut Blaise Pascal 7ac27a0ecSDave Kleikamp * Universite Pierre et Marie Curie (Paris VI) 8ac27a0ecSDave Kleikamp * 9ac27a0ecSDave Kleikamp * from 10ac27a0ecSDave Kleikamp * 11ac27a0ecSDave Kleikamp * linux/fs/minix/dir.c 12ac27a0ecSDave Kleikamp * 13ac27a0ecSDave Kleikamp * Copyright (C) 1991, 1992 Linus Torvalds 14ac27a0ecSDave Kleikamp * 15617ba13bSMingming Cao * ext4 directory handling functions 16ac27a0ecSDave Kleikamp * 17ac27a0ecSDave Kleikamp * Big-endian to little-endian byte-swapping/bitmaps by 18ac27a0ecSDave Kleikamp * David S. Miller (davem@caip.rutgers.edu), 1995 19ac27a0ecSDave Kleikamp * 20ac27a0ecSDave Kleikamp * Hash Tree Directory indexing (c) 2001 Daniel Phillips 21ac27a0ecSDave Kleikamp * 22ac27a0ecSDave Kleikamp */ 23ac27a0ecSDave Kleikamp 24ac27a0ecSDave Kleikamp #include <linux/fs.h> 25dab291afSMingming Cao #include <linux/jbd2.h> 26ac27a0ecSDave Kleikamp #include <linux/buffer_head.h> 27ac27a0ecSDave Kleikamp #include <linux/slab.h> 28ac27a0ecSDave Kleikamp #include <linux/rbtree.h> 293dcf5451SChristoph Hellwig #include "ext4.h" 30ac27a0ecSDave Kleikamp 31617ba13bSMingming Cao static unsigned char ext4_filetype_table[] = { 32ac27a0ecSDave Kleikamp DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK 33ac27a0ecSDave Kleikamp }; 34ac27a0ecSDave Kleikamp 35617ba13bSMingming Cao static int ext4_readdir(struct file *, void *, filldir_t); 36617ba13bSMingming Cao static int ext4_dx_readdir(struct file *filp, 37ac27a0ecSDave Kleikamp void *dirent, filldir_t filldir); 38617ba13bSMingming Cao static int ext4_release_dir(struct inode *inode, 39ac27a0ecSDave Kleikamp struct file *filp); 40ac27a0ecSDave Kleikamp 41617ba13bSMingming Cao const struct file_operations ext4_dir_operations = { 42e0d10bfaSToshiyuki Okajima .llseek = ext4_llseek, 43ac27a0ecSDave Kleikamp .read = generic_read_dir, 44617ba13bSMingming Cao .readdir = ext4_readdir, /* we take BKL. needed?*/ 455cdd7b2dSAndi Kleen .unlocked_ioctl = ext4_ioctl, 46ac27a0ecSDave Kleikamp #ifdef CONFIG_COMPAT 47617ba13bSMingming Cao .compat_ioctl = ext4_compat_ioctl, 48ac27a0ecSDave Kleikamp #endif 49642be6ecSAndi Kleen .fsync = ext4_sync_file, 50617ba13bSMingming Cao .release = ext4_release_dir, 51ac27a0ecSDave Kleikamp }; 52ac27a0ecSDave Kleikamp 53ac27a0ecSDave Kleikamp 54ac27a0ecSDave Kleikamp static unsigned char get_dtype(struct super_block *sb, int filetype) 55ac27a0ecSDave Kleikamp { 56617ba13bSMingming Cao if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) || 57617ba13bSMingming Cao (filetype >= EXT4_FT_MAX)) 58ac27a0ecSDave Kleikamp return DT_UNKNOWN; 59ac27a0ecSDave Kleikamp 60617ba13bSMingming Cao return (ext4_filetype_table[filetype]); 61ac27a0ecSDave Kleikamp } 62ac27a0ecSDave Kleikamp 63cad3f007STheodore Ts'o /* 64cad3f007STheodore Ts'o * Return 0 if the directory entry is OK, and 1 if there is a problem 65cad3f007STheodore Ts'o * 66cad3f007STheodore Ts'o * Note: this is the opposite of what ext2 and ext3 historically returned... 67cad3f007STheodore Ts'o */ 6860fd4da3STheodore Ts'o int __ext4_check_dir_entry(const char *function, unsigned int line, 69f7c21177STheodore Ts'o struct inode *dir, struct file *filp, 70617ba13bSMingming Cao struct ext4_dir_entry_2 *de, 71ac27a0ecSDave Kleikamp struct buffer_head *bh, 72498e5f24STheodore Ts'o unsigned int offset) 73ac27a0ecSDave Kleikamp { 74ac27a0ecSDave Kleikamp const char *error_msg = NULL; 753d0518f4SWei Yongjun const int rlen = ext4_rec_len_from_disk(de->rec_len, 763d0518f4SWei Yongjun dir->i_sb->s_blocksize); 77ac27a0ecSDave Kleikamp 78cad3f007STheodore Ts'o if (unlikely(rlen < EXT4_DIR_REC_LEN(1))) 79ac27a0ecSDave Kleikamp error_msg = "rec_len is smaller than minimal"; 80cad3f007STheodore Ts'o else if (unlikely(rlen % 4 != 0)) 81ac27a0ecSDave Kleikamp error_msg = "rec_len % 4 != 0"; 82cad3f007STheodore Ts'o else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len))) 83ac27a0ecSDave Kleikamp error_msg = "rec_len is too small for name_len"; 84cad3f007STheodore Ts'o else if (unlikely(((char *) de - bh->b_data) + rlen > 85cad3f007STheodore Ts'o dir->i_sb->s_blocksize)) 86ac27a0ecSDave Kleikamp error_msg = "directory entry across blocks"; 87cad3f007STheodore Ts'o else if (unlikely(le32_to_cpu(de->inode) > 88cad3f007STheodore Ts'o le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count))) 89ac27a0ecSDave Kleikamp error_msg = "inode out of bounds"; 90cad3f007STheodore Ts'o else 91cad3f007STheodore Ts'o return 0; 92ac27a0ecSDave Kleikamp 93f7c21177STheodore Ts'o if (filp) 944fda4003SDan Carpenter ext4_error_file(filp, function, line, bh->b_blocknr, 95f7c21177STheodore Ts'o "bad entry in directory: %s - offset=%u(%u), " 96f7c21177STheodore Ts'o "inode=%u, rec_len=%d, name_len=%d", 97f7c21177STheodore Ts'o error_msg, (unsigned) (offset % bh->b_size), 98f7c21177STheodore Ts'o offset, le32_to_cpu(de->inode), 99ac27a0ecSDave Kleikamp rlen, de->name_len); 100f7c21177STheodore Ts'o else 1014fda4003SDan Carpenter ext4_error_inode(dir, function, line, bh->b_blocknr, 102f7c21177STheodore Ts'o "bad entry in directory: %s - offset=%u(%u), " 103f7c21177STheodore Ts'o "inode=%u, rec_len=%d, name_len=%d", 104f7c21177STheodore Ts'o error_msg, (unsigned) (offset % bh->b_size), 105f7c21177STheodore Ts'o offset, le32_to_cpu(de->inode), 106f7c21177STheodore Ts'o rlen, de->name_len); 107f7c21177STheodore Ts'o 108cad3f007STheodore Ts'o return 1; 109ac27a0ecSDave Kleikamp } 110ac27a0ecSDave Kleikamp 111617ba13bSMingming Cao static int ext4_readdir(struct file *filp, 112ac27a0ecSDave Kleikamp void *dirent, filldir_t filldir) 113ac27a0ecSDave Kleikamp { 114ac27a0ecSDave Kleikamp int error = 0; 115498e5f24STheodore Ts'o unsigned int offset; 116ac27a0ecSDave Kleikamp int i, stored; 117617ba13bSMingming Cao struct ext4_dir_entry_2 *de; 118ac27a0ecSDave Kleikamp struct super_block *sb; 119ac27a0ecSDave Kleikamp int err; 1209d549890SJosef "Jeff" Sipek struct inode *inode = filp->f_path.dentry->d_inode; 121ac27a0ecSDave Kleikamp int ret = 0; 1229d9f1775SEric Sandeen int dir_has_error = 0; 123ac27a0ecSDave Kleikamp 124ac27a0ecSDave Kleikamp sb = inode->i_sb; 125ac27a0ecSDave Kleikamp 126617ba13bSMingming Cao if (EXT4_HAS_COMPAT_FEATURE(inode->i_sb, 127617ba13bSMingming Cao EXT4_FEATURE_COMPAT_DIR_INDEX) && 12812e9b892SDmitry Monakhov ((ext4_test_inode_flag(inode, EXT4_INODE_INDEX)) || 129ac27a0ecSDave Kleikamp ((inode->i_size >> sb->s_blocksize_bits) == 1))) { 130617ba13bSMingming Cao err = ext4_dx_readdir(filp, dirent, filldir); 131ac27a0ecSDave Kleikamp if (err != ERR_BAD_DX_DIR) { 132ac27a0ecSDave Kleikamp ret = err; 133ac27a0ecSDave Kleikamp goto out; 134ac27a0ecSDave Kleikamp } 135ac27a0ecSDave Kleikamp /* 136ac27a0ecSDave Kleikamp * We don't set the inode dirty flag since it's not 137ac27a0ecSDave Kleikamp * critical that it get flushed back to the disk. 138ac27a0ecSDave Kleikamp */ 13907a03824STheodore Ts'o ext4_clear_inode_flag(filp->f_path.dentry->d_inode, 14007a03824STheodore Ts'o EXT4_INODE_INDEX); 141ac27a0ecSDave Kleikamp } 142ac27a0ecSDave Kleikamp stored = 0; 143ac27a0ecSDave Kleikamp offset = filp->f_pos & (sb->s_blocksize - 1); 144ac27a0ecSDave Kleikamp 145ac27a0ecSDave Kleikamp while (!error && !stored && filp->f_pos < inode->i_size) { 1462ed88685STheodore Ts'o struct ext4_map_blocks map; 147ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 148ac27a0ecSDave Kleikamp 1492ed88685STheodore Ts'o map.m_lblk = filp->f_pos >> EXT4_BLOCK_SIZE_BITS(sb); 1502ed88685STheodore Ts'o map.m_len = 1; 1512ed88685STheodore Ts'o err = ext4_map_blocks(NULL, inode, &map, 0); 152ac27a0ecSDave Kleikamp if (err > 0) { 1532ed88685STheodore Ts'o pgoff_t index = map.m_pblk >> 154dc7868fcSFengguang Wu (PAGE_CACHE_SHIFT - inode->i_blkbits); 155dc7868fcSFengguang Wu if (!ra_has_index(&filp->f_ra, index)) 156cf914a7dSRusty Russell page_cache_sync_readahead( 157dc7868fcSFengguang Wu sb->s_bdev->bd_inode->i_mapping, 158dc7868fcSFengguang Wu &filp->f_ra, filp, 159cf914a7dSRusty Russell index, 1); 160f4e6b498SFengguang Wu filp->f_ra.prev_pos = (loff_t)index << PAGE_CACHE_SHIFT; 1612ed88685STheodore Ts'o bh = ext4_bread(NULL, inode, map.m_lblk, 0, &err); 162ac27a0ecSDave Kleikamp } 163ac27a0ecSDave Kleikamp 164ac27a0ecSDave Kleikamp /* 165ac27a0ecSDave Kleikamp * We ignore I/O errors on directories so users have a chance 166ac27a0ecSDave Kleikamp * of recovering data when there's a bad sector 167ac27a0ecSDave Kleikamp */ 168ac27a0ecSDave Kleikamp if (!bh) { 1699d9f1775SEric Sandeen if (!dir_has_error) { 170f7c21177STheodore Ts'o EXT4_ERROR_FILE(filp, 0, 171f7c21177STheodore Ts'o "directory contains a " 172f7c21177STheodore Ts'o "hole at offset %llu", 1739d9f1775SEric Sandeen (unsigned long long) filp->f_pos); 1749d9f1775SEric Sandeen dir_has_error = 1; 1759d9f1775SEric Sandeen } 176e6c40211SEric Sandeen /* corrupt size? Maybe no more blocks to read */ 177e6c40211SEric Sandeen if (filp->f_pos > inode->i_blocks << 9) 178e6c40211SEric Sandeen break; 179ac27a0ecSDave Kleikamp filp->f_pos += sb->s_blocksize - offset; 180ac27a0ecSDave Kleikamp continue; 181ac27a0ecSDave Kleikamp } 182ac27a0ecSDave Kleikamp 183ac27a0ecSDave Kleikamp revalidate: 184ac27a0ecSDave Kleikamp /* If the dir block has changed since the last call to 185ac27a0ecSDave Kleikamp * readdir(2), then we might be pointing to an invalid 186ac27a0ecSDave Kleikamp * dirent right now. Scan from the start of the block 187ac27a0ecSDave Kleikamp * to make sure. */ 188ac27a0ecSDave Kleikamp if (filp->f_version != inode->i_version) { 189ac27a0ecSDave Kleikamp for (i = 0; i < sb->s_blocksize && i < offset; ) { 190617ba13bSMingming Cao de = (struct ext4_dir_entry_2 *) 191ac27a0ecSDave Kleikamp (bh->b_data + i); 192ac27a0ecSDave Kleikamp /* It's too expensive to do a full 193ac27a0ecSDave Kleikamp * dirent test each time round this 194ac27a0ecSDave Kleikamp * loop, but we do have to test at 195ac27a0ecSDave Kleikamp * least that it is non-zero. A 196ac27a0ecSDave Kleikamp * failure will be detected in the 197ac27a0ecSDave Kleikamp * dirent test below. */ 1983d0518f4SWei Yongjun if (ext4_rec_len_from_disk(de->rec_len, 1993d0518f4SWei Yongjun sb->s_blocksize) < EXT4_DIR_REC_LEN(1)) 200ac27a0ecSDave Kleikamp break; 2013d0518f4SWei Yongjun i += ext4_rec_len_from_disk(de->rec_len, 2023d0518f4SWei Yongjun sb->s_blocksize); 203ac27a0ecSDave Kleikamp } 204ac27a0ecSDave Kleikamp offset = i; 205ac27a0ecSDave Kleikamp filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1)) 206ac27a0ecSDave Kleikamp | offset; 207ac27a0ecSDave Kleikamp filp->f_version = inode->i_version; 208ac27a0ecSDave Kleikamp } 209ac27a0ecSDave Kleikamp 210ac27a0ecSDave Kleikamp while (!error && filp->f_pos < inode->i_size 211ac27a0ecSDave Kleikamp && offset < sb->s_blocksize) { 212617ba13bSMingming Cao de = (struct ext4_dir_entry_2 *) (bh->b_data + offset); 213f7c21177STheodore Ts'o if (ext4_check_dir_entry(inode, filp, de, 214ac27a0ecSDave Kleikamp bh, offset)) { 21563f57933SAndrew Morton /* 21663f57933SAndrew Morton * On error, skip the f_pos to the next block 21763f57933SAndrew Morton */ 218ac27a0ecSDave Kleikamp filp->f_pos = (filp->f_pos | 219ac27a0ecSDave Kleikamp (sb->s_blocksize - 1)) + 1; 220ac27a0ecSDave Kleikamp brelse(bh); 221ac27a0ecSDave Kleikamp ret = stored; 222ac27a0ecSDave Kleikamp goto out; 223ac27a0ecSDave Kleikamp } 2243d0518f4SWei Yongjun offset += ext4_rec_len_from_disk(de->rec_len, 2253d0518f4SWei Yongjun sb->s_blocksize); 226ac27a0ecSDave Kleikamp if (le32_to_cpu(de->inode)) { 227ac27a0ecSDave Kleikamp /* We might block in the next section 228ac27a0ecSDave Kleikamp * if the data destination is 229ac27a0ecSDave Kleikamp * currently swapped out. So, use a 230ac27a0ecSDave Kleikamp * version stamp to detect whether or 231ac27a0ecSDave Kleikamp * not the directory has been modified 232ac27a0ecSDave Kleikamp * during the copy operation. 233ac27a0ecSDave Kleikamp */ 2342b47c361SMathieu Desnoyers u64 version = filp->f_version; 235ac27a0ecSDave Kleikamp 236ac27a0ecSDave Kleikamp error = filldir(dirent, de->name, 237ac27a0ecSDave Kleikamp de->name_len, 238ac27a0ecSDave Kleikamp filp->f_pos, 239ac27a0ecSDave Kleikamp le32_to_cpu(de->inode), 240ac27a0ecSDave Kleikamp get_dtype(sb, de->file_type)); 241ac27a0ecSDave Kleikamp if (error) 242ac27a0ecSDave Kleikamp break; 243ac27a0ecSDave Kleikamp if (version != filp->f_version) 244ac27a0ecSDave Kleikamp goto revalidate; 245ac27a0ecSDave Kleikamp stored++; 246ac27a0ecSDave Kleikamp } 2473d0518f4SWei Yongjun filp->f_pos += ext4_rec_len_from_disk(de->rec_len, 2483d0518f4SWei Yongjun sb->s_blocksize); 249ac27a0ecSDave Kleikamp } 250ac27a0ecSDave Kleikamp offset = 0; 251ac27a0ecSDave Kleikamp brelse(bh); 252ac27a0ecSDave Kleikamp } 253ac27a0ecSDave Kleikamp out: 254ac27a0ecSDave Kleikamp return ret; 255ac27a0ecSDave Kleikamp } 256ac27a0ecSDave Kleikamp 257ac27a0ecSDave Kleikamp /* 258ac27a0ecSDave Kleikamp * These functions convert from the major/minor hash to an f_pos 259ac27a0ecSDave Kleikamp * value. 260ac27a0ecSDave Kleikamp * 261ac27a0ecSDave Kleikamp * Currently we only use major hash numer. This is unfortunate, but 262ac27a0ecSDave Kleikamp * on 32-bit machines, the same VFS interface is used for lseek and 263ac27a0ecSDave Kleikamp * llseek, so if we use the 64 bit offset, then the 32-bit versions of 264ac27a0ecSDave Kleikamp * lseek/telldir/seekdir will blow out spectacularly, and from within 265ac27a0ecSDave Kleikamp * the ext2 low-level routine, we don't know if we're being called by 266ac27a0ecSDave Kleikamp * a 64-bit version of the system call or the 32-bit version of the 267ac27a0ecSDave Kleikamp * system call. Worse yet, NFSv2 only allows for a 32-bit readdir 268ac27a0ecSDave Kleikamp * cookie. Sigh. 269ac27a0ecSDave Kleikamp */ 270ac27a0ecSDave Kleikamp #define hash2pos(major, minor) (major >> 1) 271ac27a0ecSDave Kleikamp #define pos2maj_hash(pos) ((pos << 1) & 0xffffffff) 272ac27a0ecSDave Kleikamp #define pos2min_hash(pos) (0) 273ac27a0ecSDave Kleikamp 274ac27a0ecSDave Kleikamp /* 275ac27a0ecSDave Kleikamp * This structure holds the nodes of the red-black tree used to store 276ac27a0ecSDave Kleikamp * the directory entry in hash order. 277ac27a0ecSDave Kleikamp */ 278ac27a0ecSDave Kleikamp struct fname { 279ac27a0ecSDave Kleikamp __u32 hash; 280ac27a0ecSDave Kleikamp __u32 minor_hash; 281ac27a0ecSDave Kleikamp struct rb_node rb_hash; 282ac27a0ecSDave Kleikamp struct fname *next; 283ac27a0ecSDave Kleikamp __u32 inode; 284ac27a0ecSDave Kleikamp __u8 name_len; 285ac27a0ecSDave Kleikamp __u8 file_type; 286ac27a0ecSDave Kleikamp char name[0]; 287ac27a0ecSDave Kleikamp }; 288ac27a0ecSDave Kleikamp 289ac27a0ecSDave Kleikamp /* 290ac27a0ecSDave Kleikamp * This functoin implements a non-recursive way of freeing all of the 291ac27a0ecSDave Kleikamp * nodes in the red-black tree. 292ac27a0ecSDave Kleikamp */ 293ac27a0ecSDave Kleikamp static void free_rb_tree_fname(struct rb_root *root) 294ac27a0ecSDave Kleikamp { 295ac27a0ecSDave Kleikamp struct rb_node *n = root->rb_node; 296ac27a0ecSDave Kleikamp struct rb_node *parent; 297ac27a0ecSDave Kleikamp struct fname *fname; 298ac27a0ecSDave Kleikamp 299ac27a0ecSDave Kleikamp while (n) { 300ac27a0ecSDave Kleikamp /* Do the node's children first */ 30169baee06SShen Feng if (n->rb_left) { 302ac27a0ecSDave Kleikamp n = n->rb_left; 303ac27a0ecSDave Kleikamp continue; 304ac27a0ecSDave Kleikamp } 305ac27a0ecSDave Kleikamp if (n->rb_right) { 306ac27a0ecSDave Kleikamp n = n->rb_right; 307ac27a0ecSDave Kleikamp continue; 308ac27a0ecSDave Kleikamp } 309ac27a0ecSDave Kleikamp /* 310ac27a0ecSDave Kleikamp * The node has no children; free it, and then zero 311ac27a0ecSDave Kleikamp * out parent's link to it. Finally go to the 312ac27a0ecSDave Kleikamp * beginning of the loop and try to free the parent 313ac27a0ecSDave Kleikamp * node. 314ac27a0ecSDave Kleikamp */ 315ac27a0ecSDave Kleikamp parent = rb_parent(n); 316ac27a0ecSDave Kleikamp fname = rb_entry(n, struct fname, rb_hash); 317ac27a0ecSDave Kleikamp while (fname) { 318ac27a0ecSDave Kleikamp struct fname *old = fname; 319ac27a0ecSDave Kleikamp fname = fname->next; 320ac27a0ecSDave Kleikamp kfree(old); 321ac27a0ecSDave Kleikamp } 322ac27a0ecSDave Kleikamp if (!parent) 32364e290ecSVenkatesh Pallipadi *root = RB_ROOT; 324ac27a0ecSDave Kleikamp else if (parent->rb_left == n) 325ac27a0ecSDave Kleikamp parent->rb_left = NULL; 326ac27a0ecSDave Kleikamp else if (parent->rb_right == n) 327ac27a0ecSDave Kleikamp parent->rb_right = NULL; 328ac27a0ecSDave Kleikamp n = parent; 329ac27a0ecSDave Kleikamp } 330ac27a0ecSDave Kleikamp } 331ac27a0ecSDave Kleikamp 332ac27a0ecSDave Kleikamp 33369baee06SShen Feng static struct dir_private_info *ext4_htree_create_dir_info(loff_t pos) 334ac27a0ecSDave Kleikamp { 335ac27a0ecSDave Kleikamp struct dir_private_info *p; 336ac27a0ecSDave Kleikamp 33769baee06SShen Feng p = kzalloc(sizeof(struct dir_private_info), GFP_KERNEL); 338ac27a0ecSDave Kleikamp if (!p) 339ac27a0ecSDave Kleikamp return NULL; 340ac27a0ecSDave Kleikamp p->curr_hash = pos2maj_hash(pos); 341ac27a0ecSDave Kleikamp p->curr_minor_hash = pos2min_hash(pos); 342ac27a0ecSDave Kleikamp return p; 343ac27a0ecSDave Kleikamp } 344ac27a0ecSDave Kleikamp 345617ba13bSMingming Cao void ext4_htree_free_dir_info(struct dir_private_info *p) 346ac27a0ecSDave Kleikamp { 347ac27a0ecSDave Kleikamp free_rb_tree_fname(&p->root); 348ac27a0ecSDave Kleikamp kfree(p); 349ac27a0ecSDave Kleikamp } 350ac27a0ecSDave Kleikamp 351ac27a0ecSDave Kleikamp /* 352ac27a0ecSDave Kleikamp * Given a directory entry, enter it into the fname rb tree. 353ac27a0ecSDave Kleikamp */ 354617ba13bSMingming Cao int ext4_htree_store_dirent(struct file *dir_file, __u32 hash, 355ac27a0ecSDave Kleikamp __u32 minor_hash, 356617ba13bSMingming Cao struct ext4_dir_entry_2 *dirent) 357ac27a0ecSDave Kleikamp { 358ac27a0ecSDave Kleikamp struct rb_node **p, *parent = NULL; 359ac27a0ecSDave Kleikamp struct fname *fname, *new_fn; 360ac27a0ecSDave Kleikamp struct dir_private_info *info; 361ac27a0ecSDave Kleikamp int len; 362ac27a0ecSDave Kleikamp 363a271fe85SJoe Perches info = dir_file->private_data; 364ac27a0ecSDave Kleikamp p = &info->root.rb_node; 365ac27a0ecSDave Kleikamp 366ac27a0ecSDave Kleikamp /* Create and allocate the fname structure */ 367ac27a0ecSDave Kleikamp len = sizeof(struct fname) + dirent->name_len + 1; 368ac27a0ecSDave Kleikamp new_fn = kzalloc(len, GFP_KERNEL); 369ac27a0ecSDave Kleikamp if (!new_fn) 370ac27a0ecSDave Kleikamp return -ENOMEM; 371ac27a0ecSDave Kleikamp new_fn->hash = hash; 372ac27a0ecSDave Kleikamp new_fn->minor_hash = minor_hash; 373ac27a0ecSDave Kleikamp new_fn->inode = le32_to_cpu(dirent->inode); 374ac27a0ecSDave Kleikamp new_fn->name_len = dirent->name_len; 375ac27a0ecSDave Kleikamp new_fn->file_type = dirent->file_type; 376ac27a0ecSDave Kleikamp memcpy(new_fn->name, dirent->name, dirent->name_len); 377ac27a0ecSDave Kleikamp new_fn->name[dirent->name_len] = 0; 378ac27a0ecSDave Kleikamp 379ac27a0ecSDave Kleikamp while (*p) { 380ac27a0ecSDave Kleikamp parent = *p; 381ac27a0ecSDave Kleikamp fname = rb_entry(parent, struct fname, rb_hash); 382ac27a0ecSDave Kleikamp 383ac27a0ecSDave Kleikamp /* 384ac27a0ecSDave Kleikamp * If the hash and minor hash match up, then we put 385ac27a0ecSDave Kleikamp * them on a linked list. This rarely happens... 386ac27a0ecSDave Kleikamp */ 387ac27a0ecSDave Kleikamp if ((new_fn->hash == fname->hash) && 388ac27a0ecSDave Kleikamp (new_fn->minor_hash == fname->minor_hash)) { 389ac27a0ecSDave Kleikamp new_fn->next = fname->next; 390ac27a0ecSDave Kleikamp fname->next = new_fn; 391ac27a0ecSDave Kleikamp return 0; 392ac27a0ecSDave Kleikamp } 393ac27a0ecSDave Kleikamp 394ac27a0ecSDave Kleikamp if (new_fn->hash < fname->hash) 395ac27a0ecSDave Kleikamp p = &(*p)->rb_left; 396ac27a0ecSDave Kleikamp else if (new_fn->hash > fname->hash) 397ac27a0ecSDave Kleikamp p = &(*p)->rb_right; 398ac27a0ecSDave Kleikamp else if (new_fn->minor_hash < fname->minor_hash) 399ac27a0ecSDave Kleikamp p = &(*p)->rb_left; 400ac27a0ecSDave Kleikamp else /* if (new_fn->minor_hash > fname->minor_hash) */ 401ac27a0ecSDave Kleikamp p = &(*p)->rb_right; 402ac27a0ecSDave Kleikamp } 403ac27a0ecSDave Kleikamp 404ac27a0ecSDave Kleikamp rb_link_node(&new_fn->rb_hash, parent, p); 405ac27a0ecSDave Kleikamp rb_insert_color(&new_fn->rb_hash, &info->root); 406ac27a0ecSDave Kleikamp return 0; 407ac27a0ecSDave Kleikamp } 408ac27a0ecSDave Kleikamp 409ac27a0ecSDave Kleikamp 410ac27a0ecSDave Kleikamp 411ac27a0ecSDave Kleikamp /* 412617ba13bSMingming Cao * This is a helper function for ext4_dx_readdir. It calls filldir 413ac27a0ecSDave Kleikamp * for all entres on the fname linked list. (Normally there is only 414ac27a0ecSDave Kleikamp * one entry on the linked list, unless there are 62 bit hash collisions.) 415ac27a0ecSDave Kleikamp */ 416ac27a0ecSDave Kleikamp static int call_filldir(struct file *filp, void *dirent, 417ac27a0ecSDave Kleikamp filldir_t filldir, struct fname *fname) 418ac27a0ecSDave Kleikamp { 419ac27a0ecSDave Kleikamp struct dir_private_info *info = filp->private_data; 420ac27a0ecSDave Kleikamp loff_t curr_pos; 4219d549890SJosef "Jeff" Sipek struct inode *inode = filp->f_path.dentry->d_inode; 422ac27a0ecSDave Kleikamp struct super_block *sb; 423ac27a0ecSDave Kleikamp int error; 424ac27a0ecSDave Kleikamp 425ac27a0ecSDave Kleikamp sb = inode->i_sb; 426ac27a0ecSDave Kleikamp 427ac27a0ecSDave Kleikamp if (!fname) { 428abda1418STheodore Ts'o printk(KERN_ERR "EXT4-fs: call_filldir: called with " 4294776004fSTheodore Ts'o "null fname?!?\n"); 430ac27a0ecSDave Kleikamp return 0; 431ac27a0ecSDave Kleikamp } 432ac27a0ecSDave Kleikamp curr_pos = hash2pos(fname->hash, fname->minor_hash); 433ac27a0ecSDave Kleikamp while (fname) { 434ac27a0ecSDave Kleikamp error = filldir(dirent, fname->name, 435ac27a0ecSDave Kleikamp fname->name_len, curr_pos, 436ac27a0ecSDave Kleikamp fname->inode, 437ac27a0ecSDave Kleikamp get_dtype(sb, fname->file_type)); 438ac27a0ecSDave Kleikamp if (error) { 439ac27a0ecSDave Kleikamp filp->f_pos = curr_pos; 440d0156417STheodore Ts'o info->extra_fname = fname; 441ac27a0ecSDave Kleikamp return error; 442ac27a0ecSDave Kleikamp } 443ac27a0ecSDave Kleikamp fname = fname->next; 444ac27a0ecSDave Kleikamp } 445ac27a0ecSDave Kleikamp return 0; 446ac27a0ecSDave Kleikamp } 447ac27a0ecSDave Kleikamp 448617ba13bSMingming Cao static int ext4_dx_readdir(struct file *filp, 449ac27a0ecSDave Kleikamp void *dirent, filldir_t filldir) 450ac27a0ecSDave Kleikamp { 451ac27a0ecSDave Kleikamp struct dir_private_info *info = filp->private_data; 4529d549890SJosef "Jeff" Sipek struct inode *inode = filp->f_path.dentry->d_inode; 453ac27a0ecSDave Kleikamp struct fname *fname; 454ac27a0ecSDave Kleikamp int ret; 455ac27a0ecSDave Kleikamp 456ac27a0ecSDave Kleikamp if (!info) { 45769baee06SShen Feng info = ext4_htree_create_dir_info(filp->f_pos); 458ac27a0ecSDave Kleikamp if (!info) 459ac27a0ecSDave Kleikamp return -ENOMEM; 460ac27a0ecSDave Kleikamp filp->private_data = info; 461ac27a0ecSDave Kleikamp } 462ac27a0ecSDave Kleikamp 463617ba13bSMingming Cao if (filp->f_pos == EXT4_HTREE_EOF) 464ac27a0ecSDave Kleikamp return 0; /* EOF */ 465ac27a0ecSDave Kleikamp 466ac27a0ecSDave Kleikamp /* Some one has messed with f_pos; reset the world */ 467ac27a0ecSDave Kleikamp if (info->last_pos != filp->f_pos) { 468ac27a0ecSDave Kleikamp free_rb_tree_fname(&info->root); 469ac27a0ecSDave Kleikamp info->curr_node = NULL; 470ac27a0ecSDave Kleikamp info->extra_fname = NULL; 471ac27a0ecSDave Kleikamp info->curr_hash = pos2maj_hash(filp->f_pos); 472ac27a0ecSDave Kleikamp info->curr_minor_hash = pos2min_hash(filp->f_pos); 473ac27a0ecSDave Kleikamp } 474ac27a0ecSDave Kleikamp 475ac27a0ecSDave Kleikamp /* 476ac27a0ecSDave Kleikamp * If there are any leftover names on the hash collision 477ac27a0ecSDave Kleikamp * chain, return them first. 478ac27a0ecSDave Kleikamp */ 479d0156417STheodore Ts'o if (info->extra_fname) { 480d0156417STheodore Ts'o if (call_filldir(filp, dirent, filldir, info->extra_fname)) 481ac27a0ecSDave Kleikamp goto finished; 482d0156417STheodore Ts'o info->extra_fname = NULL; 4833c37fc86STheodore Ts'o goto next_node; 484d0156417STheodore Ts'o } else if (!info->curr_node) 485ac27a0ecSDave Kleikamp info->curr_node = rb_first(&info->root); 486ac27a0ecSDave Kleikamp 487ac27a0ecSDave Kleikamp while (1) { 488ac27a0ecSDave Kleikamp /* 489ac27a0ecSDave Kleikamp * Fill the rbtree if we have no more entries, 490ac27a0ecSDave Kleikamp * or the inode has changed since we last read in the 491ac27a0ecSDave Kleikamp * cached entries. 492ac27a0ecSDave Kleikamp */ 493ac27a0ecSDave Kleikamp if ((!info->curr_node) || 494ac27a0ecSDave Kleikamp (filp->f_version != inode->i_version)) { 495ac27a0ecSDave Kleikamp info->curr_node = NULL; 496ac27a0ecSDave Kleikamp free_rb_tree_fname(&info->root); 497ac27a0ecSDave Kleikamp filp->f_version = inode->i_version; 498617ba13bSMingming Cao ret = ext4_htree_fill_tree(filp, info->curr_hash, 499ac27a0ecSDave Kleikamp info->curr_minor_hash, 500ac27a0ecSDave Kleikamp &info->next_hash); 501ac27a0ecSDave Kleikamp if (ret < 0) 502ac27a0ecSDave Kleikamp return ret; 503ac27a0ecSDave Kleikamp if (ret == 0) { 504617ba13bSMingming Cao filp->f_pos = EXT4_HTREE_EOF; 505ac27a0ecSDave Kleikamp break; 506ac27a0ecSDave Kleikamp } 507ac27a0ecSDave Kleikamp info->curr_node = rb_first(&info->root); 508ac27a0ecSDave Kleikamp } 509ac27a0ecSDave Kleikamp 510ac27a0ecSDave Kleikamp fname = rb_entry(info->curr_node, struct fname, rb_hash); 511ac27a0ecSDave Kleikamp info->curr_hash = fname->hash; 512ac27a0ecSDave Kleikamp info->curr_minor_hash = fname->minor_hash; 513ac27a0ecSDave Kleikamp if (call_filldir(filp, dirent, filldir, fname)) 514ac27a0ecSDave Kleikamp break; 5153c37fc86STheodore Ts'o next_node: 516ac27a0ecSDave Kleikamp info->curr_node = rb_next(info->curr_node); 5173c37fc86STheodore Ts'o if (info->curr_node) { 5183c37fc86STheodore Ts'o fname = rb_entry(info->curr_node, struct fname, 5193c37fc86STheodore Ts'o rb_hash); 5203c37fc86STheodore Ts'o info->curr_hash = fname->hash; 5213c37fc86STheodore Ts'o info->curr_minor_hash = fname->minor_hash; 5223c37fc86STheodore Ts'o } else { 523ac27a0ecSDave Kleikamp if (info->next_hash == ~0) { 524617ba13bSMingming Cao filp->f_pos = EXT4_HTREE_EOF; 525ac27a0ecSDave Kleikamp break; 526ac27a0ecSDave Kleikamp } 527ac27a0ecSDave Kleikamp info->curr_hash = info->next_hash; 528ac27a0ecSDave Kleikamp info->curr_minor_hash = 0; 529ac27a0ecSDave Kleikamp } 530ac27a0ecSDave Kleikamp } 531ac27a0ecSDave Kleikamp finished: 532ac27a0ecSDave Kleikamp info->last_pos = filp->f_pos; 533ac27a0ecSDave Kleikamp return 0; 534ac27a0ecSDave Kleikamp } 535ac27a0ecSDave Kleikamp 536617ba13bSMingming Cao static int ext4_release_dir(struct inode *inode, struct file *filp) 537ac27a0ecSDave Kleikamp { 538ac27a0ecSDave Kleikamp if (filp->private_data) 539617ba13bSMingming Cao ext4_htree_free_dir_info(filp->private_data); 540ac27a0ecSDave Kleikamp 541ac27a0ecSDave Kleikamp return 0; 542ac27a0ecSDave Kleikamp } 543