/* * COPYRIGHT: See COPYRIGHT.TXT * PROJECT: Ext2 File System Driver for WinNT/2K/XP * FILE: lock.c * PROGRAMMER: Matt Wu * HOMEPAGE: http://www.ext2fsd.com * UPDATE HISTORY: * Copied from linux/lib/halfmd4.c * linux/fs/ext3/hash.c */ /* INCLUDES *****************************************************************/ #include "ext2fs.h" #ifdef EXT2_HTREE_INDEX #define DX_DEBUG 0 #if DX_DEBUG #define dxtrace(command) command #else #define dxtrace(command) #endif #ifndef swap #define swap(type, x, y) do { type z = x; x = y; y = z; } while (0) #endif /* F, G and H are basic MD4 functions: selection, majority, parity */ #define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z)))) #define G(x, y, z) (((x) & (y)) + (((x) ^ (y)) & (z))) #define H(x, y, z) ((x) ^ (y) ^ (z)) /* * The generic round function. The application is so specific that * we don't bother protecting all the arguments with parens, as is generally * good macro practice, in favor of extra legibility. * Rotation is separate from addition to prevent recomputation */ #define ROUND(f, a, b, c, d, x, s) \ (a += f(b, c, d) + x, a = (a << s) | (a >> (32 - s))) #define K1 0 #define K2 013240474631 #define K3 015666365641 /* * Basic cut-down MD4 transform. Returns only 32 bits of result. */ __u32 half_md4_transform(__u32 buf[4], __u32 const in[8]) { __u32 a = buf[0], b = buf[1], c = buf[2], d = buf[3]; /* Round 1 */ ROUND(F, a, b, c, d, in[0] + K1, 3); ROUND(F, d, a, b, c, in[1] + K1, 7); ROUND(F, c, d, a, b, in[2] + K1, 11); ROUND(F, b, c, d, a, in[3] + K1, 19); ROUND(F, a, b, c, d, in[4] + K1, 3); ROUND(F, d, a, b, c, in[5] + K1, 7); ROUND(F, c, d, a, b, in[6] + K1, 11); ROUND(F, b, c, d, a, in[7] + K1, 19); /* Round 2 */ ROUND(G, a, b, c, d, in[1] + K2, 3); ROUND(G, d, a, b, c, in[3] + K2, 5); ROUND(G, c, d, a, b, in[5] + K2, 9); ROUND(G, b, c, d, a, in[7] + K2, 13); ROUND(G, a, b, c, d, in[0] + K2, 3); ROUND(G, d, a, b, c, in[2] + K2, 5); ROUND(G, c, d, a, b, in[4] + K2, 9); ROUND(G, b, c, d, a, in[6] + K2, 13); /* Round 3 */ ROUND(H, a, b, c, d, in[3] + K3, 3); ROUND(H, d, a, b, c, in[7] + K3, 9); ROUND(H, c, d, a, b, in[2] + K3, 11); ROUND(H, b, c, d, a, in[6] + K3, 15); ROUND(H, a, b, c, d, in[1] + K3, 3); ROUND(H, d, a, b, c, in[5] + K3, 9); ROUND(H, c, d, a, b, in[0] + K3, 11); ROUND(H, b, c, d, a, in[4] + K3, 15); buf[0] += a; buf[1] += b; buf[2] += c; buf[3] += d; return buf[1]; /* "most hashed" word */ } #define DELTA 0x9E3779B9 static void TEA_transform(__u32 buf[4], __u32 const in[]) { __u32 sum = 0; __u32 b0 = buf[0], b1 = buf[1]; __u32 a = in[0], b = in[1], c = in[2], d = in[3]; int n = 16; do { sum += DELTA; b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b); b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d); } while (--n); buf[0] += b0; buf[1] += b1; } /* The old legacy hash */ static __u32 dx_hack_hash_unsigned(const char *name, int len) { __u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9; const unsigned char *ucp = (const unsigned char *) name; while (len--) { hash = hash1 + (hash0 ^ (((int) *ucp++) * 7152373)); if (hash & 0x80000000) hash -= 0x7fffffff; hash1 = hash0; hash0 = hash; } return hash0 << 1; } static __u32 dx_hack_hash_signed(const char *name, int len) { __u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9; const signed char *scp = (const signed char *) name; while (len--) { hash = hash1 + (hash0 ^ (((int) *scp++) * 7152373)); if (hash & 0x80000000) hash -= 0x7fffffff; hash1 = hash0; hash0 = hash; } return hash0 << 1; } static void str2hashbuf_signed(const char *msg, int len, __u32 *buf, int num) { __u32 pad, val; int i; const signed char *scp = (const signed char *) msg; pad = (__u32)len | ((__u32)len << 8); pad |= pad << 16; val = pad; if (len > num*4) len = num * 4; for (i = 0; i < len; i++) { if ((i % 4) == 0) val = pad; val = ((int) scp[i]) + (val << 8); if ((i % 4) == 3) { *buf++ = val; val = pad; num--; } } if (--num >= 0) *buf++ = val; while (--num >= 0) *buf++ = pad; } static void str2hashbuf_unsigned(const char *msg, int len, __u32 *buf, int num) { __u32 pad, val; int i; const unsigned char *ucp = (const unsigned char *) msg; pad = (__u32)len | ((__u32)len << 8); pad |= pad << 16; val = pad; if (len > num*4) len = num * 4; for (i = 0; i < len; i++) { if ((i % 4) == 0) val = pad; val = ((int) ucp[i]) + (val << 8); if ((i % 4) == 3) { *buf++ = val; val = pad; num--; } } if (--num >= 0) *buf++ = val; while (--num >= 0) *buf++ = pad; } #endif /* EXT2_HTREE_INDEX */ __u32 ext3_current_time(struct inode *in) { LARGE_INTEGER SysTime; KeQuerySystemTime(&SysTime); return Ext2LinuxTime(SysTime); } void ext3_warning (struct super_block * sb, const char * function, char * fmt, ...) { #if DX_DEBUG va_list args; va_start(args, fmt); printk("EXT3-fs warning (device %s): %s: ", sb->s_id, function); printk(fmt, args); printk("\n"); va_end(args); #endif } /* ext3_bread is safe for meta-data blocks. it's not safe to read file data, since file data is managed by file cache, not volume cache */ struct buffer_head *ext3_bread(struct ext2_icb *icb, struct inode *inode, unsigned long block, int *err) { struct buffer_head * bh = NULL; NTSTATUS status = STATUS_SUCCESS; ULONG lbn = 0, num = 0; PEXT2_MCB Mcb = CONTAINING_RECORD(inode, EXT2_MCB, Inode); /* for symlink file, read it's target instead */ if (NULL != Mcb && IsMcbSymLink(Mcb)) Mcb = Mcb->Target; if (NULL == Mcb) { *err = -EINVAL; return NULL; } /* mapping file offset to ext2 block */ if (INODE_HAS_EXTENT(&Mcb->Inode)) { status = Ext2MapExtent(icb, inode->i_sb->s_priv, Mcb, block, FALSE, &lbn, &num); } else { status = Ext2MapIndirect(icb, inode->i_sb->s_priv, Mcb, block, FALSE, &lbn, &num); } if (!NT_SUCCESS(status)) { *err = Ext2LinuxError(status); return bh; } bh = sb_getblk(inode->i_sb, lbn); if (!bh) { *err = -ENOMEM; return bh; } if (buffer_uptodate(bh)) return bh; *err = bh_submit_read(bh); if (*err) { __brelse(bh); return NULL; } return bh; } struct buffer_head *ext3_append(struct ext2_icb *icb, struct inode *inode, ext3_lblk_t *block, int *err) { PEXT2_MCB mcb = CONTAINING_RECORD(inode, EXT2_MCB, Inode); PEXT2_FCB dcb = mcb->Fcb; NTSTATUS status; ASSERT(dcb); ASSERT(inode == dcb->Inode); /* allocate new block since there's no space for us */ *block = (ext3_lblk_t)(inode->i_size >> inode->i_sb->s_blocksize_bits); dcb->Header.AllocationSize.QuadPart += dcb->Vcb->BlockSize; status = Ext2ExpandFile(icb, dcb->Vcb, mcb, &(dcb->Header.AllocationSize)); if (NT_SUCCESS(status)) { /* update Dcb */ dcb->Header.ValidDataLength = dcb->Header.FileSize = dcb->Header.AllocationSize; mcb->Inode.i_size = dcb->Header.AllocationSize.QuadPart; /* save parent directory's inode */ Ext2SaveInode(icb, dcb->Vcb, inode); } return ext3_bread(icb, inode, *block, err); } void ext3_inc_count(struct inode *inode) { inode->i_nlink++; } void ext3_dec_count(struct inode *inode) { inode->i_nlink--; } unsigned char ext3_type_by_mode(umode_t mode) { unsigned char type = 0; switch (mode & S_IFMT) { case S_IFREG: type = EXT3_FT_REG_FILE; break; case S_IFDIR: type = EXT3_FT_DIR; break; case S_IFCHR: type = EXT3_FT_CHRDEV; break; case S_IFBLK: type = EXT3_FT_BLKDEV; break; case S_IFIFO: type = EXT3_FT_FIFO; break; case S_IFSOCK: type = EXT3_FT_SOCK; break; case S_IFLNK: type = EXT3_FT_SYMLINK; } return type; }; void ext3_set_de_type(struct super_block *sb, struct ext3_dir_entry_2 *de, umode_t mode) { if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE)) de->file_type = ext3_type_by_mode(mode); } /* * ext3_mark_inode_dirty is somewhat expensive, so unlike ext2 we * do not perform it in these functions. We perform it at the call site, * if it is needed. */ int ext3_mark_inode_dirty(struct ext2_icb *icb, struct inode *in) { if (Ext2SaveInode(icb, in->i_sb->s_priv, in)) return 0; return -ENOMEM; } void ext3_update_dx_flag(struct inode *inode) { if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL; } /* * Add a new entry into a directory (leaf) block. If de is non-NULL, * it points to a directory entry which is guaranteed to be large * enough for new directory entry. If de is NULL, then * add_dirent_to_buf will attempt search the directory block for * space. It will return -ENOSPC if no space is available, and -EIO * and -EEXIST if directory entry already exists. * * NOTE! bh is NOT released in the case where ENOSPC is returned. In * all other cases bh is released. */ int add_dirent_to_buf(struct ext2_icb *icb, struct dentry *dentry, struct inode *inode, struct ext3_dir_entry_2 *de, struct buffer_head *bh) { struct inode *dir = dentry->d_parent->d_inode; const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; unsigned int offset = 0; unsigned short reclen; int nlen, rlen, err; char *top; reclen = EXT3_DIR_REC_LEN(namelen); if (!de) { de = (struct ext3_dir_entry_2 *)bh->b_data; top = bh->b_data + dir->i_sb->s_blocksize - reclen; while ((char *) de <= top) { if (!ext3_check_dir_entry("ext3_add_entry", dir, de, bh, offset)) { __brelse(bh); return -EIO; } if (ext3_match(namelen, name, de)) { __brelse(bh); return -EEXIST; } nlen = EXT3_DIR_REC_LEN(de->name_len); rlen = ext3_rec_len_from_disk(de->rec_len); if ((de->inode? rlen - nlen: rlen) >= reclen) break; de = (struct ext3_dir_entry_2 *)((char *)de + rlen); offset += rlen; } if ((char *) de > top) return -ENOSPC; } /* By now the buffer is marked for journaling */ nlen = EXT3_DIR_REC_LEN(de->name_len); rlen = ext3_rec_len_from_disk(de->rec_len); if (de->inode) { struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen); de1->rec_len = ext3_rec_len_to_disk(rlen - nlen); de->rec_len = ext3_rec_len_to_disk(nlen); de = de1; } de->file_type = EXT3_FT_UNKNOWN; if (inode) { de->inode = cpu_to_le32(inode->i_ino); ext3_set_de_type(dir->i_sb, de, inode->i_mode); } else de->inode = 0; de->name_len = (__u8)namelen; memcpy(de->name, name, namelen); /* * XXX shouldn't update any times until successful * completion of syscall, but too many callers depend * on this. * * XXX similarly, too many callers depend on * ext4_new_inode() setting the times, but error * recovery deletes the inode, so the worst that can * happen is that the times are slightly out of date * and/or different from the directory change time. */ dir->i_mtime = dir->i_ctime = ext3_current_time(dir); ext3_update_dx_flag(dir); dir->i_version++; ext3_mark_inode_dirty(icb, dir); set_buffer_dirty(bh); __brelse(bh); return 0; } #ifdef EXT2_HTREE_INDEX /* * Returns the hash of a filename. If len is 0 and name is NULL, then * this function can be used to test whether or not a hash version is * supported. * * The seed is an 4 longword (32 bits) "secret" which can be used to * uniquify a hash. If the seed is all zero's, then some default seed * may be used. * * A particular hash version specifies whether or not the seed is * represented, and whether or not the returned hash is 32 bits or 64 * bits. 32 bit hashes will return 0 for the minor hash. */ int ext3_dirhash(const char *name, int len, struct dx_hash_info *hinfo) { __u32 hash; __u32 minor_hash = 0; const char *p; int i; __u32 in[8], buf[4]; void (*str2hashbuf)(const char *, int, __u32 *, int) = str2hashbuf_signed; /* Initialize the default seed for the hash checksum functions */ buf[0] = 0x67452301; buf[1] = 0xefcdab89; buf[2] = 0x98badcfe; buf[3] = 0x10325476; /* Check to see if the seed is all zero's */ if (hinfo->seed) { for (i = 0; i < 4; i++) { if (hinfo->seed[i]) break; } if (i < 4) memcpy(buf, hinfo->seed, sizeof(buf)); } switch (hinfo->hash_version) { case DX_HASH_LEGACY_UNSIGNED: hash = dx_hack_hash_unsigned(name, len); break; case DX_HASH_LEGACY: hash = dx_hack_hash_signed(name, len); break; case DX_HASH_HALF_MD4_UNSIGNED: str2hashbuf = str2hashbuf_unsigned; case DX_HASH_HALF_MD4: p = name; while (len > 0) { (*str2hashbuf)(p, len, in, 8); half_md4_transform(buf, in); len -= 32; p += 32; } minor_hash = buf[2]; hash = buf[1]; break; case DX_HASH_TEA_UNSIGNED: str2hashbuf = str2hashbuf_unsigned; case DX_HASH_TEA: p = name; while (len > 0) { (*str2hashbuf)(p, len, in, 4); TEA_transform(buf, in); len -= 16; p += 16; } hash = buf[0]; minor_hash = buf[1]; break; default: hinfo->hash = 0; return -1; } hash = hash & ~1; if (hash == (EXT4_HTREE_EOF_32BIT << 1)) hash = (EXT4_HTREE_EOF_32BIT - 1) << 1; hinfo->hash = hash; hinfo->minor_hash = minor_hash; return 0; } EXPORT_SYMBOL(ext3_dirhash); /* * These functions convert from the major/minor hash to an f_pos * value. * * Currently we only use major hash numer. This is unfortunate, but * on 32-bit machines, the same VFS interface is used for lseek and * llseek, so if we use the 64 bit offset, then the 32-bit versions of * lseek/telldir/seekdir will blow out spectacularly, and from within * the ext2 low-level routine, we don't know if we're being called by * a 64-bit version of the system call or the 32-bit version of the * system call. Worse yet, NFSv2 only allows for a 32-bit readdir * cookie. Sigh. */ #define hash2pos(major, minor) (major >> 1) #define pos2maj_hash(pos) ((pos << 1) & 0xffffffff) #define pos2min_hash(pos) (0) /* * This structure holds the nodes of the red-black tree used to store * the directory entry in hash order. */ struct fname { __u32 hash; __u32 minor_hash; struct rb_node rb_hash; struct fname *next; __u32 inode; __u8 name_len; __u8 file_type; char name[0]; }; /* * This functoin implements a non-recursive way of freeing all of the * nodes in the red-black tree. */ static void free_rb_tree_fname(struct rb_root *root) { struct rb_node *n = root->rb_node; struct rb_node *parent; struct fname *fname; while (n) { /* Do the node's children first */ if ((n)->rb_left) { n = n->rb_left; continue; } if (n->rb_right) { n = n->rb_right; continue; } /* * The node has no children; free it, and then zero * out parent's link to it. Finally go to the * beginning of the loop and try to free the parent * node. */ parent = rb_parent(n); fname = rb_entry(n, struct fname, rb_hash); while (fname) { struct fname * old = fname; fname = fname->next; kfree (old); } if (!parent) root->rb_node = NULL; else if (parent->rb_left == n) parent->rb_left = NULL; else if (parent->rb_right == n) parent->rb_right = NULL; n = parent; } root->rb_node = NULL; } static struct dir_private_info *create_dir_info(loff_t pos) { struct dir_private_info *p; p = kmalloc(sizeof(struct dir_private_info), GFP_KERNEL); if (!p) return NULL; p->root.rb_node = NULL; p->curr_node = NULL; p->extra_fname = NULL; p->last_pos = 0; p->curr_hash = (__u32)pos2maj_hash(pos); p->curr_minor_hash = (__u32)pos2min_hash(pos); p->next_hash = 0; return p; } void ext3_htree_free_dir_info(struct dir_private_info *p) { free_rb_tree_fname(&p->root); kfree(p); } /* * Given a directory entry, enter it into the fname rb tree. */ int ext3_htree_store_dirent(struct file *dir_file, __u32 hash, __u32 minor_hash, struct ext3_dir_entry_2 *dirent) { struct rb_node **p, *parent = NULL; struct fname * fname, *new_fn; struct dir_private_info *info; int extra_data = 0; int len; info = (struct dir_private_info *) dir_file->private_data; p = &info->root.rb_node; /* Create and allocate the fname structure */ if (dirent->file_type & EXT3_DIRENT_LUFID) extra_data = ext3_get_dirent_data_len(dirent); len = sizeof(struct fname) + dirent->name_len + extra_data; new_fn = kmalloc(len, GFP_KERNEL); if (!new_fn) return -ENOMEM; memset(new_fn, 0, len); new_fn->hash = hash; new_fn->minor_hash = minor_hash; new_fn->inode = le32_to_cpu(dirent->inode); new_fn->name_len = dirent->name_len; new_fn->file_type = dirent->file_type; memcpy(&new_fn->name[0], &dirent->name[0], dirent->name_len + extra_data); new_fn->name[dirent->name_len] = 0; while (*p) { parent = *p; fname = rb_entry(parent, struct fname, rb_hash); /* * If the hash and minor hash match up, then we put * them on a linked list. This rarely happens... */ if ((new_fn->hash == fname->hash) && (new_fn->minor_hash == fname->minor_hash)) { new_fn->next = fname->next; fname->next = new_fn; return 0; } if (new_fn->hash < fname->hash) p = &(*p)->rb_left; else if (new_fn->hash > fname->hash) p = &(*p)->rb_right; else if (new_fn->minor_hash < fname->minor_hash) p = &(*p)->rb_left; else /* if (new_fn->minor_hash > fname->minor_hash) */ p = &(*p)->rb_right; } rb_link_node(&new_fn->rb_hash, parent, p); rb_insert_color(&new_fn->rb_hash, &info->root); return 0; } static unsigned char ext3_filetype_table[] = { DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK }; static unsigned char get_dtype(struct super_block *sb, int filetype) { if (!EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE) || (filetype >= EXT3_FT_MAX)) return DT_UNKNOWN; return (ext3_filetype_table[filetype]); } /* * This is a helper function for ext3_dx_readdir. It calls filldir * for all entres on the fname linked list. (Normally there is only * one entry on the linked list, unless there are 62 bit hash collisions.) */ static int call_filldir(struct file * filp, void * cookie, filldir_t filldir, struct fname *fname) { struct dir_private_info *info = filp->private_data; loff_t curr_pos; struct inode *inode = filp->f_dentry->d_inode; struct super_block * sb; int error; sb = inode->i_sb; if (!fname) { printk("call_filldir: called with null fname?!?\n"); return 0; } curr_pos = hash2pos(fname->hash, fname->minor_hash); while (fname) { error = filldir(cookie, fname->name, fname->name_len, (ULONG)curr_pos, fname->inode, get_dtype(sb, fname->file_type)); if (error) { filp->f_pos = curr_pos; info->extra_fname = fname; return error; } fname = fname->next; } return 0; } struct fake_dirent { __le32 inode; __le16 rec_len; __u8 name_len; __u8 file_type; }; struct dx_countlimit { __le16 limit; __le16 count; }; struct dx_entry { __le32 hash; __le32 block; }; /* * dx_root_info is laid out so that if it should somehow get overlaid by a * dirent the two low bits of the hash version will be zero. Therefore, the * hash version mod 4 should never be 0. Sincerely, the paranoia department. */ struct dx_root { struct fake_dirent dot; char dot_name[4]; struct fake_dirent dotdot; char dotdot_name[4]; struct dx_root_info { __le32 reserved_zero; __u8 hash_version; __u8 info_length; /* 8 */ __u8 indirect_levels; __u8 unused_flags; } info; struct dx_entry entries[0]; }; struct dx_node { struct fake_dirent fake; struct dx_entry entries[0]; }; struct dx_frame { struct buffer_head *bh; struct dx_entry *entries; struct dx_entry *at; }; struct dx_map_entry { __u32 hash; __u16 offs; __u16 size; }; #if defined(__REACTOS__) && !defined(_MSC_VER) struct ext3_dir_entry_2 * do_split(struct ext2_icb *icb, struct inode *dir, struct buffer_head **bh,struct dx_frame *frame, struct dx_hash_info *hinfo, int *error); #endif /* * Future: use high four bits of block for coalesce-on-delete flags * Mask them off for now. */ static inline unsigned dx_get_block (struct dx_entry *entry) { return le32_to_cpu(entry->block) & 0x00ffffff; } static inline void dx_set_block (struct dx_entry *entry, unsigned value) { entry->block = cpu_to_le32(value); } static inline unsigned dx_get_hash (struct dx_entry *entry) { return le32_to_cpu(entry->hash); } static inline void dx_set_hash (struct dx_entry *entry, unsigned value) { entry->hash = cpu_to_le32(value); } static inline unsigned dx_get_count (struct dx_entry *entries) { return le16_to_cpu(((struct dx_countlimit *) entries)->count); } static inline unsigned dx_get_limit (struct dx_entry *entries) { return le16_to_cpu(((struct dx_countlimit *) entries)->limit); } static inline void dx_set_count (struct dx_entry *entries, unsigned value) { ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); } static inline void dx_set_limit (struct dx_entry *entries, unsigned value) { ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); } static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize) { unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) - EXT3_DIR_REC_LEN(2) - infosize; return 0? 20: entry_space / sizeof(struct dx_entry); } static inline unsigned dx_node_limit (struct inode *dir) { unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0); return 0? 22: entry_space / sizeof(struct dx_entry); } /* * Debug */ #if DX_DEBUG static void dx_show_index (char * label, struct dx_entry *entries) { int i, n = dx_get_count (entries); printk("%s index ", label); for (i = 0; i < n; i++) { printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i)); } printk("\n"); } struct stats { unsigned names; unsigned space; unsigned bcount; }; struct stats dx_show_leaf(struct ext2_icb *icb, struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de, int size, int show_names) { struct stats rc; unsigned names = 0, space = 0; char *base = (char *) de; struct dx_hash_info h = *hinfo; printk("names: "); while ((char *) de < base + size) { if (de->inode) { if (show_names) { int len = de->name_len; char *name = de->name; while (len--) printk("%c", *name++); ext3_dirhash(de->name, de->name_len, &h); printk(":%x.%u ", h.hash, ((char *) de - base)); } space += EXT3_DIR_REC_LEN(de->name_len); names++; } de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); } printk("(%i)\n", names); rc.names = names; rc.space = space; rc.bcount = 1; return rc; } struct stats dx_show_entries(struct ext2_icb *icb, struct dx_hash_info *hinfo, struct inode *dir, struct dx_entry *entries, int levels) { unsigned blocksize = dir->i_sb->s_blocksize; unsigned count = dx_get_count (entries), names = 0, space = 0, i; unsigned bcount = 0; struct buffer_head *bh; struct stats rc; int err; printk("%i indexed blocks...\n", count); for (i = 0; i < count; i++, entries++) { u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0; u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; struct stats stats; printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); if (!(bh = ext3_bread (icb, dir, block, &err))) continue; stats = levels? dx_show_entries(icb, hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): dx_show_leaf(icb, hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0); names += stats.names; space += stats.space; bcount += stats.bcount; __brelse (bh); } if (bcount) printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ", names, space/bcount,(space/bcount)*100/blocksize); rc.names = names; rc.space = space; rc.bcount = 1; return rc; } #endif /* DX_DEBUG */ int ext3_save_inode ( struct ext2_icb *icb, struct inode *in) { return Ext2SaveInode(icb, in->i_sb->s_priv, in); } /* * Probe for a directory leaf block to search. * * dx_probe can return ERR_BAD_DX_DIR, which means there was a format * error in the directory index, and the caller should fall back to * searching the directory normally. The callers of dx_probe **MUST** * check for this error code, and make sure it never gets reflected * back to userspace. */ static struct dx_frame * dx_probe(struct ext2_icb *icb, struct dentry *dentry, struct inode *dir, struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err) { unsigned count, indirect; struct dx_entry *at, *entries, *p, *q, *m; struct dx_root *root; struct buffer_head *bh; struct dx_frame *frame = frame_in; u32 hash; frame->bh = NULL; if (dentry) dir = dentry->d_parent->d_inode; if (!(bh = ext3_bread (icb, dir, 0, err))) goto fail; root = (struct dx_root *) bh->b_data; if (root->info.hash_version != DX_HASH_TEA && root->info.hash_version != DX_HASH_HALF_MD4 && root->info.hash_version != DX_HASH_LEGACY) { ext3_warning(dir->i_sb, __FUNCTION__, "Unrecognised inode hash code %d", root->info.hash_version); __brelse(bh); *err = ERR_BAD_DX_DIR; goto fail; } hinfo->hash_version = root->info.hash_version; hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed; if (dentry) ext3_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo); hash = hinfo->hash; if (root->info.unused_flags & 1) { ext3_warning(dir->i_sb, __FUNCTION__, "Unimplemented inode hash flags: %#06x", root->info.unused_flags); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail; } if ((indirect = root->info.indirect_levels) > 1) { ext3_warning(dir->i_sb, __FUNCTION__, "Unimplemented inode hash depth: %#06x", root->info.indirect_levels); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail; } entries = (struct dx_entry *) (((char *)&root->info) + root->info.info_length); if (dx_get_limit(entries) != dx_root_limit(dir, root->info.info_length)) { ext3_warning(dir->i_sb, __FUNCTION__, "dx entry: limit != root limit"); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail; } dxtrace(printk("Look up %x", hash)); while (1) { count = dx_get_count(entries); if (!count || count > dx_get_limit(entries)) { ext3_warning(dir->i_sb, __FUNCTION__, "dx entry: no count or count > limit"); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail2; } p = entries + 1; q = entries + count - 1; while (p <= q) { m = p + (q - p)/2; if (dx_get_hash(m) > hash) q = m - 1; else p = m + 1; } if (0) // linear search cross check { unsigned n = count - 1; at = entries; while (n--) { if (dx_get_hash(++at) > hash) { at--; break; } } ASSERT(at == p - 1); } at = p - 1; frame->bh = bh; frame->entries = entries; frame->at = at; if (!indirect--) return frame; if (!(bh = ext3_bread(icb, dir, dx_get_block(at), err))) goto fail2; at = entries = ((struct dx_node *) bh->b_data)->entries; if (dx_get_limit(entries) != dx_node_limit (dir)) { ext3_warning(dir->i_sb, __FUNCTION__, "dx entry: limit != node limit"); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail2; } frame++; frame->bh = NULL; } fail2: while (frame >= frame_in) { brelse(frame->bh); frame--; } fail: if (*err == ERR_BAD_DX_DIR) ext3_warning(dir->i_sb, __FUNCTION__, "Corrupt dir inode %ld, running e2fsck is " "recommended.", dir->i_ino); return NULL; } static void dx_release (struct dx_frame *frames) { if (frames[0].bh == NULL) return; if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels) brelse(frames[1].bh); brelse(frames[0].bh); } /* * This function increments the frame pointer to search the next leaf * block, and reads in the necessary intervening nodes if the search * should be necessary. Whether or not the search is necessary is * controlled by the hash parameter. If the hash value is even, then * the search is only continued if the next block starts with that * hash value. This is used if we are searching for a specific file. * * If the hash value is HASH_NB_ALWAYS, then always go to the next block. * * This function returns 1 if the caller should continue to search, * or 0 if it should not. If there is an error reading one of the * index blocks, it will a negative error code. * * If start_hash is non-null, it will be filled in with the starting * hash of the next page. */ int ext3_htree_next_block(struct ext2_icb *icb, struct inode *dir, __u32 hash, struct dx_frame *frame, struct dx_frame *frames, __u32 *start_hash) { struct dx_frame *p; struct buffer_head *bh; int err, num_frames = 0; __u32 bhash; p = frame; /* * Find the next leaf page by incrementing the frame pointer. * If we run out of entries in the interior node, loop around and * increment pointer in the parent node. When we break out of * this loop, num_frames indicates the number of interior * nodes need to be read. */ while (1) { if (++(p->at) < p->entries + dx_get_count(p->entries)) break; if (p == frames) return 0; num_frames++; p--; } /* * If the hash is 1, then continue only if the next page has a * continuation hash of any value. This is used for readdir * handling. Otherwise, check to see if the hash matches the * desired contiuation hash. If it doesn't, return since * there's no point to read in the successive index pages. */ bhash = dx_get_hash(p->at); if (start_hash) *start_hash = bhash; if ((hash & 1) == 0) { if ((bhash & ~1) != hash) return 0; } /* * If the hash is HASH_NB_ALWAYS, we always go to the next * block so no check is necessary */ while (num_frames--) { if (!(bh = ext3_bread(icb, dir, dx_get_block(p->at), &err))) return err; /* Failure */ p++; brelse (p->bh); p->bh = bh; p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; } return 1; } /* * This function fills a red-black tree with information from a * directory block. It returns the number directory entries loaded * into the tree. If there is an error it is returned in err. */ int htree_dirblock_to_tree(struct ext2_icb *icb, struct file *dir_file, struct inode *dir, int block, struct dx_hash_info *hinfo, __u32 start_hash, __u32 start_minor_hash) { struct buffer_head *bh; struct ext3_dir_entry_2 *de, *top; int err, count = 0; dxtrace(printk("In htree dirblock_to_tree: block %d\n", block)); if (!(bh = ext3_bread (icb, dir, block, &err))) return err; de = (struct ext3_dir_entry_2 *) bh->b_data; top = (struct ext3_dir_entry_2 *) ((char *) de + dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0)); for (; de < top; de = ext3_next_entry(de)) { if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh, ((unsigned long)block<i_sb)) + (unsigned long)((char *)de - bh->b_data))) { /* On error, skip the f_pos to the next block. */ dir_file->f_pos = (dir_file->f_pos | (dir->i_sb->s_blocksize - 1)) + 1; brelse (bh); return count; } ext3_dirhash(de->name, de->name_len, hinfo); if ((hinfo->hash < start_hash) || ((hinfo->hash == start_hash) && (hinfo->minor_hash < start_minor_hash))) continue; if (de->inode == 0) continue; if ((err = ext3_htree_store_dirent(dir_file, hinfo->hash, hinfo->minor_hash, de)) != 0) { brelse(bh); return err; } count++; } brelse(bh); return count; } /* * This function fills a red-black tree with information from a * directory. We start scanning the directory in hash order, starting * at start_hash and start_minor_hash. * * This function returns the number of entries inserted into the tree, * or a negative error code. */ int ext3_htree_fill_tree(struct ext2_icb *icb, struct file *dir_file, __u32 start_hash, __u32 start_minor_hash, __u32 *next_hash) { struct dx_hash_info hinfo; struct ext3_dir_entry_2 *de; struct dx_frame frames[2], *frame; int block, err = 0; struct inode *dir; int count = 0; int ret; __u32 hashval; dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash, start_minor_hash)); dir = dir_file->f_dentry->d_inode; if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) { hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; count = htree_dirblock_to_tree(icb, dir_file, dir, 0, &hinfo, start_hash, start_minor_hash); *next_hash = ~0; return count; } hinfo.hash = start_hash; hinfo.minor_hash = 0; frame = dx_probe(icb, NULL, dir_file->f_dentry->d_inode, &hinfo, frames, &err); if (!frame) return err; /* Add '.' and '..' from the htree header */ if (!start_hash && !start_minor_hash) { de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0) goto errout; count++; } if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; de = ext3_next_entry(de); if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0) goto errout; count++; } while (1) { block = dx_get_block(frame->at); ret = htree_dirblock_to_tree(icb, dir_file, dir, block, &hinfo, start_hash, start_minor_hash); if (ret < 0) { err = ret; goto errout; } count += ret; hashval = ~0; ret = ext3_htree_next_block(icb, dir, HASH_NB_ALWAYS, frame, frames, &hashval); *next_hash = hashval; if (ret < 0) { err = ret; goto errout; } /* * Stop if: (a) there are no more entries, or * (b) we have inserted at least one entry and the * next hash value is not a continuation */ if ((ret == 0) || (count && ((hashval & 1) == 0))) break; } dx_release(frames); dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n", count, *next_hash)); return count; errout: dx_release(frames); return (err); } /* * Directory block splitting, compacting */ /* * Create map of hash values, offsets, and sizes, stored at end of block. * Returns number of entries mapped. */ static int dx_make_map (struct ext3_dir_entry_2 *de, int size, struct dx_hash_info *hinfo, struct dx_map_entry *map_tail) { int count = 0; char *base = (char *) de; struct dx_hash_info h = *hinfo; while ((char *) de < base + size) { if (de->name_len && de->inode) { ext3_dirhash(de->name, de->name_len, &h); map_tail--; map_tail->hash = h.hash; map_tail->offs = (u16) ((char *) de - base); map_tail->size = le16_to_cpu(de->rec_len); count++; cond_resched(); } /* XXX: do we need to check rec_len == 0 case? -Chris */ de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); } return count; } /* Sort map by hash value */ static void dx_sort_map (struct dx_map_entry *map, unsigned count) { struct dx_map_entry *p, *q, *top = map + count - 1; int more; /* Combsort until bubble sort doesn't suck */ while (count > 2) { count = count*10/13; if (count - 9 < 2) /* 9, 10 -> 11 */ count = 11; for (p = top, q = p - count; q >= map; p--, q--) if (p->hash < q->hash) swap(struct dx_map_entry, *p, *q); } /* Garden variety bubble sort */ do { more = 0; q = top; while (q-- > map) { if (q[1].hash >= q[0].hash) continue; swap(struct dx_map_entry, *(q+1), *q); more = 1; } } while (more); } static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block) { struct dx_entry *entries = frame->entries; struct dx_entry *old = frame->at, *new = old + 1; unsigned int count = dx_get_count(entries); ASSERT(count < dx_get_limit(entries)); ASSERT(old < entries + count); memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); dx_set_hash(new, hash); dx_set_block(new, block); dx_set_count(entries, count + 1); } struct buffer_head * ext3_dx_find_entry(struct ext2_icb *icb, struct dentry *dentry, struct ext3_dir_entry_2 **res_dir, int *err) { struct super_block * sb; struct dx_hash_info hinfo = {0}; u32 hash; struct dx_frame frames[2], *frame; struct ext3_dir_entry_2 *de, *top; struct buffer_head *bh; unsigned long block; int retval; int namelen = dentry->d_name.len; const __u8 *name = dentry->d_name.name; struct inode *dir = dentry->d_parent->d_inode; sb = dir->i_sb; /* NFS may look up ".." - look at dx_root directory block */ if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')) { if (!(frame = dx_probe(icb, dentry, NULL, &hinfo, frames, err))) return NULL; } else { frame = frames; frame->bh = NULL; /* for dx_release() */ frame->at = (struct dx_entry *)frames; /* hack for zero entry*/ dx_set_block(frame->at, 0); /* dx_root block is 0 */ } hash = hinfo.hash; do { block = dx_get_block(frame->at); if (!(bh = ext3_bread (icb, dir, block, err))) goto errout; de = (struct ext3_dir_entry_2 *) bh->b_data; top = (struct ext3_dir_entry_2 *) ((char *) de + sb->s_blocksize - EXT3_DIR_REC_LEN(0)); for (; de < top; de = ext3_next_entry(de)) if (ext3_match (namelen, name, de)) { if (!ext3_check_dir_entry("ext3_find_entry", dir, de, bh, (block<b_data))) { brelse (bh); goto errout; } *res_dir = de; dx_release (frames); return bh; } brelse (bh); /* Check to see if we should continue to search */ retval = ext3_htree_next_block(icb, dir, hash, frame, frames, NULL); if (retval < 0) { ext3_warning(sb, __FUNCTION__, "error reading index page in directory #%lu", dir->i_ino); *err = retval; goto errout; } } while (retval == 1); *err = -ENOENT; errout: dxtrace(printk("%s not found\n", name)); dx_release (frames); return NULL; } int ext3_dx_readdir(struct file *filp, filldir_t filldir, void * context) { struct dir_private_info *info = filp->private_data; struct inode *inode = filp->f_dentry->d_inode; struct fname *fname; PEXT2_FILLDIR_CONTEXT fc = context; int ret; if (!info) { info = create_dir_info(filp->f_pos); if (!info) return -ENOMEM; filp->private_data = info; } if (filp->f_pos == EXT3_HTREE_EOF) return 0; /* EOF */ /* Some one has messed with f_pos; reset the world */ if (info->last_pos != filp->f_pos) { free_rb_tree_fname(&info->root); info->curr_node = NULL; info->extra_fname = NULL; info->curr_hash = (__u32)pos2maj_hash(filp->f_pos); info->curr_minor_hash = (__u32)pos2min_hash(filp->f_pos); } /* * If there are any leftover names on the hash collision * chain, return them first. */ if (info->extra_fname) { if (call_filldir(filp, context, filldir, info->extra_fname)) goto finished; info->extra_fname = NULL; goto next_node; } else if (!info->curr_node) info->curr_node = rb_first(&info->root); while (1) { /* * Fill the rbtree if we have no more entries, * or the inode has changed since we last read in the * cached entries. */ if ((!info->curr_node) || (filp->f_version != inode->i_version)) { info->curr_node = NULL; free_rb_tree_fname(&info->root); filp->f_version = inode->i_version; ret = ext3_htree_fill_tree(fc->efc_irp, filp, info->curr_hash, info->curr_minor_hash, &info->next_hash); if (ret < 0) return ret; if (ret == 0) { filp->f_pos = EXT3_HTREE_EOF; break; } info->curr_node = rb_first(&info->root); } fname = rb_entry(info->curr_node, struct fname, rb_hash); info->curr_hash = fname->hash; info->curr_minor_hash = fname->minor_hash; if (call_filldir(filp, context, filldir, fname)) break; next_node: info->curr_node = rb_next(info->curr_node); if (info->curr_node) { fname = rb_entry(info->curr_node, struct fname, rb_hash); info->curr_hash = fname->hash; info->curr_minor_hash = fname->minor_hash; } else { if (info->next_hash == ~0) { filp->f_pos = EXT3_HTREE_EOF; break; } info->curr_hash = info->next_hash; info->curr_minor_hash = 0; } } finished: info->last_pos = filp->f_pos; return 0; } int ext3_release_dir (struct inode * inode, struct file * filp) { if (filp->private_data) { ext3_htree_free_dir_info(filp->private_data); filp->private_data = NULL; } return 0; } /* FIXME: Inspect the clang-cl code path */ #if defined(__REACTOS__) && defined(__clang__) struct ext3_dir_entry_2* do_split(struct ext2_icb *icb, struct inode *dir, struct buffer_head **bh,struct dx_frame *frame, struct dx_hash_info *hinfo, int *error); #endif /* * Returns 0 for success, or a negative error value */ int ext3_dx_add_entry(struct ext2_icb *icb, struct dentry *dentry, struct inode *inode) { struct dx_frame frames[2], *frame; struct dx_entry *entries, *at; struct dx_hash_info hinfo; struct buffer_head * bh; struct inode *dir = dentry->d_parent->d_inode; struct super_block * sb = dir->i_sb; struct ext3_dir_entry_2 *de; int err; frame = dx_probe(icb, dentry, NULL, &hinfo, frames, &err); if (!frame) return err; entries = frame->entries; at = frame->at; if (!(bh = ext3_bread(icb, dir, dx_get_block(frame->at), &err))) goto cleanup; err = add_dirent_to_buf(icb, dentry, inode, NULL, bh); if (err != -ENOSPC) { bh = NULL; goto cleanup; } /* Block full, should compress but for now just split */ dxtrace(printk("using %u of %u node entries\n", dx_get_count(entries), dx_get_limit(entries))); /* Need to split index? */ if (dx_get_count(entries) == dx_get_limit(entries)) { u32 newblock; unsigned icount = dx_get_count(entries); int levels = (int)(frame - frames); struct dx_entry *entries2; struct dx_node *node2; struct buffer_head *bh2; if (levels && (dx_get_count(frames->entries) == dx_get_limit(frames->entries))) { ext3_warning(sb, __FUNCTION__, "Directory index full!"); err = -ENOSPC; goto cleanup; } bh2 = ext3_append (icb, dir, &newblock, &err); if (!(bh2)) goto cleanup; node2 = (struct dx_node *)(bh2->b_data); entries2 = node2->entries; node2->fake.rec_len = cpu_to_le16(sb->s_blocksize); node2->fake.inode = 0; if (levels) { unsigned icount1 = icount/2, icount2 = icount - icount1; unsigned hash2 = dx_get_hash(entries + icount1); dxtrace(printk("Split index %i/%i\n", icount1, icount2)); memcpy ((char *) entries2, (char *) (entries + icount1), icount2 * sizeof(struct dx_entry)); dx_set_count (entries, icount1); dx_set_count (entries2, icount2); dx_set_limit (entries2, dx_node_limit(dir)); /* Which index block gets the new entry? */ if ((unsigned int)(at - entries) >= icount1) { frame->at = at = at - entries - icount1 + entries2; frame->entries = entries = entries2; swap(struct buffer_head *, frame->bh, bh2); } dx_insert_block (frames + 0, hash2, newblock); dxtrace(dx_show_index ("node", frames[1].entries)); dxtrace(dx_show_index ("node", ((struct dx_node *) bh2->b_data)->entries)); set_buffer_dirty(bh2); brelse (bh2); } else { dxtrace(printk("Creating second level index...\n")); memcpy((char *) entries2, (char *) entries, icount * sizeof(struct dx_entry)); dx_set_limit(entries2, dx_node_limit(dir)); /* Set up root */ dx_set_count(entries, 1); dx_set_block(entries + 0, newblock); ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1; /* Add new access path frame */ frame = frames + 1; frame->at = at = at - entries + entries2; frame->entries = entries = entries2; frame->bh = bh2; } // ext3_journal_dirty_metadata(handle, frames[0].bh); set_buffer_dirty(frames[0].bh); } de = do_split(icb, dir, &bh, frame, &hinfo, &err); if (!de) goto cleanup; err = add_dirent_to_buf(icb, dentry, inode, de, bh); bh = NULL; goto cleanup; cleanup: if (bh) brelse(bh); dx_release(frames); return err; } /* * Move count entries from end of map between two memory locations. * Returns pointer to last entry moved. */ struct ext3_dir_entry_2 * dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) { unsigned rec_len = 0; while (count--) { struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs); rec_len = EXT3_DIR_REC_LEN(de->name_len); memcpy (to, de, rec_len); ((struct ext3_dir_entry_2 *) to)->rec_len = cpu_to_le16(rec_len); de->inode = 0; map++; to += rec_len; } return (struct ext3_dir_entry_2 *) (to - rec_len); } /* * Compact each dir entry in the range to the minimal rec_len. * Returns pointer to last entry in range. */ struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size) { struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base; unsigned rec_len = 0; prev = to = de; while ((char*)de < base + size) { next = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); if (de->inode && de->name_len) { rec_len = EXT3_DIR_REC_LEN(de->name_len); if (de > to) memmove(to, de, rec_len); to->rec_len = cpu_to_le16(rec_len); prev = to; to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len); } de = next; } return prev; } /* * Split a full leaf block to make room for a new dir entry. * Allocate a new block, and move entries so that they are approx. equally full. * Returns pointer to de in block into which the new entry will be inserted. */ struct ext3_dir_entry_2 * do_split(struct ext2_icb *icb, struct inode *dir, struct buffer_head **bh,struct dx_frame *frame, struct dx_hash_info *hinfo, int *error) { unsigned blocksize = dir->i_sb->s_blocksize; unsigned count, continued; struct buffer_head *bh2; u32 newblock; u32 hash2; struct dx_map_entry *map; char *data1 = (*bh)->b_data, *data2; unsigned split, move, size; struct ext3_dir_entry_2 *de = NULL, *de2; int err, i; bh2 = ext3_append (icb, dir, &newblock, error); if (!(bh2)) { brelse(*bh); *bh = NULL; goto errout; } data2 = bh2->b_data; /* create map in the end of data2 block */ map = (struct dx_map_entry *) (data2 + blocksize); count = dx_make_map ((struct ext3_dir_entry_2 *) data1, blocksize, hinfo, map); map -= count; dx_sort_map (map, count); /* Split the existing block in the middle, size-wise */ size = 0; move = 0; for (i = count-1; i >= 0; i--) { /* is more than half of this entry in 2nd half of the block? */ if (size + map[i].size/2 > blocksize/2) break; size += map[i].size; move++; } /* map index at which we will split */ split = count - move; hash2 = map[split].hash; continued = hash2 == map[split - 1].hash; dxtrace(printk("Split block %i at %x, %i/%i\n", dx_get_block(frame->at), hash2, split, count-split)); /* Fancy dance to stay within two buffers */ de2 = dx_move_dirents(data1, data2, map + split, count - split); de = dx_pack_dirents(data1,blocksize); de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de); de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2); dxtrace(dx_show_leaf (icb, hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1)); dxtrace(dx_show_leaf (icb, hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1)); /* Which block gets the new entry? */ if (hinfo->hash >= hash2) { swap(struct buffer_head *, *bh, bh2); de = de2; } dx_insert_block (frame, hash2 + continued, newblock); set_buffer_dirty(bh2); set_buffer_dirty(frame->bh); brelse (bh2); dxtrace(dx_show_index ("frame", frame->entries)); errout: return de; } /* * This converts a one block unindexed directory to a 3 block indexed * directory, and adds the dentry to the indexed directory. */ int make_indexed_dir(struct ext2_icb *icb, struct dentry *dentry, struct inode *inode, struct buffer_head *bh) { struct inode *dir = dentry->d_parent->d_inode; const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; struct buffer_head *bh2; struct dx_root *root; struct dx_frame frames[2], *frame; struct dx_entry *entries; struct ext3_dir_entry_2 *de, *de2; char *data1, *top; unsigned len; int retval; unsigned blocksize; struct dx_hash_info hinfo; ext3_lblk_t block; struct fake_dirent *fde; blocksize = dir->i_sb->s_blocksize; dxtrace(printk("Creating index: inode %lu\n", dir->i_ino)); root = (struct dx_root *) bh->b_data; /* The 0th block becomes the root, move the dirents out */ fde = &root->dotdot; de = (struct ext3_dir_entry_2 *)((char *)fde + ext3_rec_len_from_disk(fde->rec_len)); if ((char *) de >= (((char *) root) + blocksize)) { DEBUG(DL_ERR, ( "%s: invalid rec_len for '..' in inode %lu", __FUNCTION__, dir->i_ino)); brelse(bh); return -EIO; } len = (unsigned int)((char *) root + blocksize - (char *) de); /* Allocate new block for the 0th block's dirents */ bh2 = ext3_append(icb, dir, &block, &retval); if (!(bh2)) { brelse(bh); return retval; } EXT3_I(dir)->i_flags |= EXT3_INDEX_FL; data1 = bh2->b_data; memcpy (data1, de, len); de = (struct ext3_dir_entry_2 *) data1; top = data1 + len; while ((char *)(de2 = ext3_next_entry(de)) < top) de = de2; de->rec_len = ext3_rec_len_to_disk(blocksize + (__u32)(data1 - (char *)de)); /* Initialize the root; the dot dirents already exist */ de = (struct ext3_dir_entry_2 *) (&root->dotdot); de->rec_len = ext3_rec_len_to_disk(blocksize - EXT3_DIR_REC_LEN(2)); memset (&root->info, 0, sizeof(root->info)); root->info.info_length = sizeof(root->info); root->info.hash_version = (__u8)(EXT3_SB(dir->i_sb)->s_def_hash_version); entries = root->entries; dx_set_block(entries, 1); dx_set_count(entries, 1); dx_set_limit(entries, dx_root_limit(dir, sizeof(root->info))); /* Initialize as for dx_probe */ hinfo.hash_version = root->info.hash_version; hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; ext3_dirhash(name, namelen, &hinfo); frame = frames; frame->entries = entries; frame->at = entries; frame->bh = bh; bh = bh2; /* bh and bh2 are to be marked as dirty in do_split */ de = do_split(icb, dir, &bh, frame, &hinfo, &retval); dx_release (frames); if (!(de)) return retval; return add_dirent_to_buf(icb, dentry, inode, de, bh); } #else /* EXT2_HTREE_INDEX */ int ext3_release_dir (struct inode * inode, struct file * filp) { return 0; } #endif /* !EXT2_HTREE_INDEX */ /* * ext3_add_entry() * * adds a file entry to the specified directory, using the same * semantics as ext3_find_entry(). It returns NULL if it failed. * * NOTE!! The inode part of 'de' is left at 0 - which means you * may not sleep between calling this and putting something into * the entry, as someone else might have used it while you slept. */ int ext3_add_entry(struct ext2_icb *icb, struct dentry *dentry, struct inode *inode) { struct inode *dir = dentry->d_parent->d_inode; struct buffer_head *bh; struct ext3_dir_entry_2 *de; struct super_block *sb; int retval; #ifdef EXT2_HTREE_INDEX int dx_fallback=0; #endif unsigned blocksize; ext3_lblk_t block, blocks; sb = dir->i_sb; blocksize = sb->s_blocksize; if (!dentry->d_name.len) return -EINVAL; #ifdef EXT2_HTREE_INDEX if (is_dx(dir)) { retval = ext3_dx_add_entry(icb, dentry, inode); if (!retval || (retval != ERR_BAD_DX_DIR)) return retval; EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL; dx_fallback++; ext3_save_inode(icb, dir); } #endif blocks = (ext3_lblk_t)(dir->i_size >> sb->s_blocksize_bits); for (block = 0; block < blocks; block++) { bh = ext3_bread(icb, dir, block, &retval); if (!bh) return retval; retval = add_dirent_to_buf(icb, dentry, inode, NULL, bh); if (retval != -ENOSPC) return retval; #ifdef EXT2_HTREE_INDEX if (blocks == 1 && !dx_fallback && EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) return make_indexed_dir(icb, dentry, inode, bh); #endif brelse(bh); } bh = ext3_append(icb, dir, &block, &retval); if (!bh) return retval; de = (struct ext3_dir_entry_2 *) bh->b_data; de->inode = 0; de->rec_len = ext3_rec_len_to_disk(blocksize); return add_dirent_to_buf(icb, dentry, inode, de, bh); } /* * ext3_delete_entry deletes a directory entry by merging it with the * previous entry */ int ext3_delete_entry(struct ext2_icb *icb, struct inode *dir, struct ext3_dir_entry_2 *de_del, struct buffer_head *bh) { struct ext3_dir_entry_2 *de, *pde = NULL; size_t i = 0; de = (struct ext3_dir_entry_2 *) bh->b_data; while (i < bh->b_size) { if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i)) return -EIO; if (de == de_del) { if (pde) pde->rec_len = ext3_rec_len_to_disk( ext3_rec_len_from_disk(pde->rec_len) + ext3_rec_len_from_disk(de->rec_len)); else de->inode = 0; dir->i_version++; /* ext3_journal_dirty_metadata(handle, bh); */ set_buffer_dirty(bh); return 0; } i += ext3_rec_len_from_disk(de->rec_len); pde = de; de = ext3_next_entry(de); } return -ENOENT; } /* * routine to check that the specified directory is empty (for rmdir) */ int ext3_is_dir_empty(struct ext2_icb *icb, struct inode *inode) { unsigned int offset; struct buffer_head *bh; struct ext3_dir_entry_2 *de, *de1; struct super_block *sb; int err = 0; sb = inode->i_sb; if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) || !(bh = ext3_bread(icb, inode, 0, &err))) { if (err) ext3_error(inode->i_sb, __FUNCTION__, "error %d reading directory #%lu offset 0", err, inode->i_ino); else ext3_warning(inode->i_sb, __FUNCTION__, "bad directory (dir #%lu) - no data block", inode->i_ino); return 1; } de = (struct ext3_dir_entry_2 *) bh->b_data; de1 = ext3_next_entry(de); if (le32_to_cpu(de->inode) != inode->i_ino || !le32_to_cpu(de1->inode) || strcmp(".", de->name) || strcmp("..", de1->name)) { ext3_warning(inode->i_sb, "empty_dir", "bad directory (dir #%lu) - no `.' or `..'", inode->i_ino); brelse(bh); return 1; } offset = ext3_rec_len_from_disk(de->rec_len) + ext3_rec_len_from_disk(de1->rec_len); de = ext3_next_entry(de1); while (offset < inode->i_size) { if (!bh || (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { err = 0; brelse(bh); bh = ext3_bread(icb, inode, offset >> EXT3_BLOCK_SIZE_BITS(sb), &err); if (!bh) { if (err) ext3_error(sb, __FUNCTION__, "error %d reading directory" " #%lu offset %u", err, inode->i_ino, offset); offset += sb->s_blocksize; continue; } de = (struct ext3_dir_entry_2 *) bh->b_data; } if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) { de = (struct ext3_dir_entry_2 *)(bh->b_data + sb->s_blocksize); offset = (offset | (sb->s_blocksize - 1)) + 1; continue; } if (le32_to_cpu(de->inode)) { brelse(bh); return 0; } offset += ext3_rec_len_from_disk(de->rec_len); de = ext3_next_entry(de); } brelse(bh); return 1; } /* * Returns 0 if not found, -1 on failure, and 1 on success */ static inline int search_dirblock(struct buffer_head * bh, struct inode *dir, struct dentry *dentry, unsigned long offset, struct ext3_dir_entry_2 ** res_dir) { struct ext3_dir_entry_2 * de; char * dlimit; int de_len; const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; de = (struct ext3_dir_entry_2 *) bh->b_data; dlimit = bh->b_data + dir->i_sb->s_blocksize; while ((char *) de < dlimit) { /* this code is executed quadratically often */ /* do minimal checking `by hand' */ if ((char *) de + namelen <= dlimit && ext3_match (namelen, name, de)) { /* found a match - just to be sure, do a full check */ if (!ext3_check_dir_entry("ext3_find_entry", dir, de, bh, offset)) return -1; *res_dir = de; return 1; } /* prevent looping on a bad block */ de_len = ext3_rec_len_from_disk(de->rec_len); if (de_len <= 0) return -1; offset += de_len; de = (struct ext3_dir_entry_2 *) ((char *) de + de_len); } return 0; } /* * define how far ahead to read directories while searching them. */ #define NAMEI_RA_CHUNKS 2 #define NAMEI_RA_BLOCKS 4 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) #define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b)) /* * ext4_find_entry() * * finds an entry in the specified directory with the wanted name. It * returns the cache buffer in which the entry was found, and the entry * itself (as a parameter - res_dir). It does NOT read the inode of the * entry - you'll have to do that yourself if you want to. * * The returned buffer_head has ->b_count elevated. The caller is expected * to brelse() it when appropriate. */ struct buffer_head * ext3_find_entry (struct ext2_icb *icb, struct dentry *dentry, struct ext3_dir_entry_2 ** res_dir) { struct inode *dir = dentry->d_parent->d_inode; struct super_block *sb = dir->i_sb; struct buffer_head *bh_use[NAMEI_RA_SIZE]; struct buffer_head *bh, *ret = NULL; ext3_lblk_t start, block, b; int ra_max = 0; /* Number of bh's in the readahead buffer, bh_use[] */ int ra_ptr = 0; /* Current index into readahead buffer */ int num = 0; ext3_lblk_t nblocks; int i, err; int namelen = dentry->d_name.len; *res_dir = NULL; if (namelen > EXT3_NAME_LEN) return NULL; #ifdef EXT2_HTREE_INDEX if (icb->MajorFunction != IRP_MJ_CREATE && is_dx(dir)) { bh = ext3_dx_find_entry(icb, dentry, res_dir, &err); /* * On success, or if the error was file not found, * return. Otherwise, fall back to doing a search the * old fashioned way. */ if (bh || (err != ERR_BAD_DX_DIR)) return bh; dxtrace(printk("ext4_find_entry: dx failed, " "falling back\n")); } #endif nblocks = (ext3_lblk_t)(dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb)); start = 0; block = start; restart: do { /* * We deal with the read-ahead logic here. */ if (ra_ptr >= ra_max) { /* Refill the readahead buffer */ ra_ptr = 0; b = block; for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) { /* * Terminate if we reach the end of the * directory and must wrap, or if our * search has finished at this block. */ if (b >= nblocks || (num && block == start)) { bh_use[ra_max] = NULL; break; } num++; bh = ext3_bread(icb, dir, b++, &err); bh_use[ra_max] = bh; } } if ((bh = bh_use[ra_ptr++]) == NULL) goto next; wait_on_buffer(bh); if (!buffer_uptodate(bh)) { /* read error, skip block & hope for the best */ ext3_error(sb, __FUNCTION__, "reading directory #%lu " "offset %lu", dir->i_ino, (unsigned long)block); brelse(bh); goto next; } i = search_dirblock(bh, dir, dentry, block << EXT3_BLOCK_SIZE_BITS(sb), res_dir); if (i == 1) { ret = bh; goto cleanup_and_exit; } else { brelse(bh); if (i < 0) goto cleanup_and_exit; } next: if (++block >= nblocks) block = 0; } while (block != start); /* * If the directory has grown while we were searching, then * search the last part of the directory before giving up. */ block = nblocks; nblocks = (ext3_lblk_t)(dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb)); if (block < nblocks) { start = 0; goto restart; } cleanup_and_exit: /* Clean up the read-ahead blocks */ for (; ra_ptr < ra_max; ra_ptr++) brelse(bh_use[ra_ptr]); return ret; }