X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=qemu%2Froms%2Fopenbios%2Ffs%2Fgrubfs%2Ffsys_reiserfs.c;fp=qemu%2Froms%2Fopenbios%2Ffs%2Fgrubfs%2Ffsys_reiserfs.c;h=b94a335291d9e6e7dd5fecddbf9314fa8ea9afd7;hb=e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb;hp=0000000000000000000000000000000000000000;hpb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;p=kvmfornfv.git diff --git a/qemu/roms/openbios/fs/grubfs/fsys_reiserfs.c b/qemu/roms/openbios/fs/grubfs/fsys_reiserfs.c new file mode 100644 index 000000000..b94a33529 --- /dev/null +++ b/qemu/roms/openbios/fs/grubfs/fsys_reiserfs.c @@ -0,0 +1,1220 @@ +/* fsys_reiserfs.c - an implementation for the ReiserFS filesystem */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2000, 2001 Free Software Foundation, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, + * MA 02110-1301, USA. + */ + +#ifdef FSYS_REISERFS +#include "shared.h" +#include "filesys.h" + +#undef REISERDEBUG + +/* Some parts of this code (mainly the structures and defines) are + * from the original reiser fs code, as found in the linux kernel. + */ + +/* include/asm-i386/types.h */ +typedef __signed__ char __s8; +typedef unsigned char __u8; +typedef __signed__ short __s16; +typedef unsigned short __u16; +typedef __signed__ int __s32; +typedef unsigned int __u32; +typedef unsigned long long __u64; + +/* linux/posix_type.h */ +typedef long linux_off_t; + +#include "libc/byteorder.h" + +/* include/linux/reiser_fs.h */ +/* This is the new super block of a journaling reiserfs system */ +struct reiserfs_super_block +{ + __u32 s_block_count; /* blocks count */ + __u32 s_free_blocks; /* free blocks count */ + __u32 s_root_block; /* root block number */ + __u32 s_journal_block; /* journal block number */ + __u32 s_journal_dev; /* journal device number */ + __u32 s_journal_size; /* size of the journal on FS creation. used to make sure they don't overflow it */ + __u32 s_journal_trans_max; /* max number of blocks in a transaction. */ + __u32 s_journal_magic; /* random value made on fs creation */ + __u32 s_journal_max_batch; /* max number of blocks to batch into a trans */ + __u32 s_journal_max_commit_age; /* in seconds, how old can an async commit be */ + __u32 s_journal_max_trans_age; /* in seconds, how old can a transaction be */ + __u16 s_blocksize; /* block size */ + __u16 s_oid_maxsize; /* max size of object id array */ + __u16 s_oid_cursize; /* current size of object id array */ + __u16 s_state; /* valid or error */ + char s_magic[16]; /* reiserfs magic string indicates that file system is reiserfs */ + __u16 s_tree_height; /* height of disk tree */ + __u16 s_bmap_nr; /* amount of bitmap blocks needed to address each block of file system */ + __u16 s_version; + char s_unused[128]; /* zero filled by mkreiserfs */ +}; + +#define REISERFS_MAX_SUPPORTED_VERSION 2 +#define REISERFS_SUPER_MAGIC_STRING "ReIsErFs" +#define REISER2FS_SUPER_MAGIC_STRING "ReIsEr2Fs" + +#define MAX_HEIGHT 7 + +/* must be correct to keep the desc and commit structs at 4k */ +#define JOURNAL_TRANS_HALF 1018 + +/* first block written in a commit. */ +struct reiserfs_journal_desc { + __u32 j_trans_id; /* id of commit */ + __u32 j_len; /* length of commit. len +1 is the commit block */ + __u32 j_mount_id; /* mount id of this trans*/ + __u32 j_realblock[JOURNAL_TRANS_HALF]; /* real locations for the first blocks */ + char j_magic[12]; +}; + +/* last block written in a commit */ +struct reiserfs_journal_commit { + __u32 j_trans_id; /* must match j_trans_id from the desc block */ + __u32 j_len; /* ditto */ + __u32 j_realblock[JOURNAL_TRANS_HALF]; /* real locations for the last blocks */ + char j_digest[16]; /* md5 sum of all the blocks involved, including desc and commit. not used, kill it */ +}; + +/* this header block gets written whenever a transaction is considered + fully flushed, and is more recent than the last fully flushed + transaction. + fully flushed means all the log blocks and all the real blocks are + on disk, and this transaction does not need to be replayed. +*/ +struct reiserfs_journal_header { + /* id of last fully flushed transaction */ + __u32 j_last_flush_trans_id; + /* offset in the log of where to start replay after a crash */ + __u32 j_first_unflushed_offset; + /* mount id to detect very old transactions */ + __u32 j_mount_id; +}; + +/* magic string to find desc blocks in the journal */ +#define JOURNAL_DESC_MAGIC "ReIsErLB" + + +/* + * directories use this key as well as old files + */ +struct offset_v1 +{ + /* + * for regular files this is the offset to the first byte of the + * body, contained in the object-item, as measured from the start of + * the entire body of the object. + * + * for directory entries, k_offset consists of hash derived from + * hashing the name and using few bits (23 or more) of the resulting + * hash, and generation number that allows distinguishing names with + * hash collisions. If number of collisions overflows generation + * number, we return EEXIST. High order bit is 0 always + */ + __u32 k_offset; + __u32 k_uniqueness; +}; + +struct offset_v2 +{ + /* + * for regular files this is the offset to the first byte of the + * body, contained in the object-item, as measured from the start of + * the entire body of the object. + * + * for directory entries, k_offset consists of hash derived from + * hashing the name and using few bits (23 or more) of the resulting + * hash, and generation number that allows distinguishing names with + * hash collisions. If number of collisions overflows generation + * number, we return EEXIST. High order bit is 0 always + */ + __u64 k_offset:60; + __u64 k_type: 4; +}; + + +struct key +{ + /* packing locality: by default parent directory object id */ + __u32 k_dir_id; + /* object identifier */ + __u32 k_objectid; + /* the offset and node type (old and new form) */ + union + { + struct offset_v1 v1; + struct offset_v2 v2; + } + u; +}; + +#define KEY_SIZE (sizeof (struct key)) + +/* Header of a disk block. More precisely, header of a formatted leaf + or internal node, and not the header of an unformatted node. */ +struct block_head +{ + __u16 blk_level; /* Level of a block in the tree. */ + __u16 blk_nr_item; /* Number of keys/items in a block. */ + __u16 blk_free_space; /* Block free space in bytes. */ + struct key blk_right_delim_key; /* Right delimiting key for this block (supported for leaf level nodes + only) */ +}; +#define BLKH_SIZE (sizeof (struct block_head)) +#define DISK_LEAF_NODE_LEVEL 1 /* Leaf node level. */ + +struct item_head +{ + struct key ih_key; /* Everything in the tree is found by searching for it based on its key.*/ + + union + { + __u16 ih_free_space; /* The free space in the last unformatted node of an indirect item if this + is an indirect item. This equals 0xFFFF iff this is a direct item or + stat data item. Note that the key, not this field, is used to determine + the item type, and thus which field this union contains. */ + __u16 ih_entry_count; /* Iff this is a directory item, this field equals the number of directory + entries in the directory item. */ + } + u; + __u16 ih_item_len; /* total size of the item body */ + __u16 ih_item_location; /* an offset to the item body within the block */ + __u16 ih_version; /* ITEM_VERSION_1 for all old items, + ITEM_VERSION_2 for new ones. + Highest bit is set by fsck + temporary, cleaned after all done */ +}; +/* size of item header */ +#define IH_SIZE (sizeof (struct item_head)) + +#define ITEM_VERSION_1 0 +#define ITEM_VERSION_2 1 +#define IH_KEY_OFFSET(ih) ((ih)->ih_version == ITEM_VERSION_1 \ + ? (ih)->ih_key.u.v1.k_offset \ + : (ih)->ih_key.u.v2.k_offset) + +#define IH_KEY_ISTYPE(ih, type) ((ih)->ih_version == ITEM_VERSION_1 \ + ? (ih)->ih_key.u.v1.k_uniqueness == V1_##type \ + : (ih)->ih_key.u.v2.k_type == V2_##type) + +/* FIXME these types look wrong. */ +struct disk_child +{ + unsigned long dc_block_number; /* Disk child's block number. */ + unsigned short dc_size; /* Disk child's used space. */ +}; + +#define DC_SIZE (sizeof (struct disk_child)) + +/* Stat Data on disk. + * + * Note that reiserfs has two different forms of stat data. Luckily + * the fields needed by grub are at the same position. + */ +struct stat_data +{ + __u16 sd_mode; /* file type, permissions */ + __u16 sd_notused1[3]; /* fields not needed by reiserfs */ + __u32 sd_size; /* file size */ + __u32 sd_size_hi; /* file size high 32 bits (since version 2) */ +}; + +struct reiserfs_de_head +{ + __u32 deh_offset; /* third component of the directory entry key */ + __u32 deh_dir_id; /* objectid of the parent directory of the + object, that is referenced by directory entry */ + __u32 deh_objectid;/* objectid of the object, that is referenced by + directory entry */ + __u16 deh_location;/* offset of name in the whole item */ + __u16 deh_state; /* whether 1) entry contains stat data (for + future), and 2) whether entry is hidden + (unlinked) */ +}; + +#define DEH_SIZE (sizeof (struct reiserfs_de_head)) + +#define DEH_Statdata (1 << 0) /* not used now */ +#define DEH_Visible (1 << 2) + +#define SD_OFFSET 0 +#define SD_UNIQUENESS 0 +#define DOT_OFFSET 1 +#define DOT_DOT_OFFSET 2 +#define DIRENTRY_UNIQUENESS 500 + +#define V1_TYPE_STAT_DATA 0x0 +#define V1_TYPE_DIRECT 0xffffffff +#define V1_TYPE_INDIRECT 0xfffffffe +#define V1_TYPE_DIRECTORY_MAX 0xfffffffd +#define V2_TYPE_STAT_DATA 0 +#define V2_TYPE_INDIRECT 1 +#define V2_TYPE_DIRECT 2 +#define V2_TYPE_DIRENTRY 3 + +#define REISERFS_ROOT_OBJECTID 2 +#define REISERFS_ROOT_PARENT_OBJECTID 1 +#define REISERFS_DISK_OFFSET_IN_BYTES (64 * 1024) +/* the spot for the super in versions 3.5 - 3.5.11 (inclusive) */ +#define REISERFS_OLD_DISK_OFFSET_IN_BYTES (8 * 1024) +#define REISERFS_OLD_BLOCKSIZE 4096 + +#define S_ISREG(mode) (((mode) & 0170000) == 0100000) +#define S_ISDIR(mode) (((mode) & 0170000) == 0040000) +#define S_ISLNK(mode) (((mode) & 0170000) == 0120000) + +#define PATH_MAX 1024 /* include/linux/limits.h */ +#define MAX_LINK_COUNT 5 /* number of symbolic links to follow */ + +/* The size of the node cache */ +#define FSYSREISER_CACHE_SIZE 24*1024 +#define FSYSREISER_MIN_BLOCKSIZE SECTOR_SIZE +#define FSYSREISER_MAX_BLOCKSIZE FSYSREISER_CACHE_SIZE / 3 + +/* Info about currently opened file */ +struct fsys_reiser_fileinfo +{ + __u32 k_dir_id; + __u32 k_objectid; +}; + +/* In memory info about the currently mounted filesystem */ +struct fsys_reiser_info +{ + /* The last read item head */ + struct item_head *current_ih; + /* The last read item */ + char *current_item; + /* The information for the currently opened file */ + struct fsys_reiser_fileinfo fileinfo; + /* The start of the journal */ + __u32 journal_block; + /* The size of the journal */ + __u32 journal_block_count; + /* The first valid descriptor block in journal + (relative to journal_block) */ + __u32 journal_first_desc; + + /* The ReiserFS version. */ + __u16 version; + /* The current depth of the reiser tree. */ + __u16 tree_depth; + /* SECTOR_SIZE << blocksize_shift == blocksize. */ + __u8 blocksize_shift; + /* 1 << full_blocksize_shift == blocksize. */ + __u8 fullblocksize_shift; + /* The reiserfs block size (must be a power of 2) */ + __u16 blocksize; + /* The number of cached tree nodes */ + __u16 cached_slots; + /* The number of valid transactions in journal */ + __u16 journal_transactions; + + unsigned int blocks[MAX_HEIGHT]; + unsigned int next_key_nr[MAX_HEIGHT]; +}; + +/* The cached s+tree blocks in FSYS_BUF, see below + * for a more detailed description. + */ +#define ROOT ((char *)FSYS_BUF) +#define CACHE(i) (ROOT + ((i) << INFO->fullblocksize_shift)) +#define LEAF CACHE (DISK_LEAF_NODE_LEVEL) + +#define BLOCKHEAD(cache) ((struct block_head *) cache) +#define ITEMHEAD ((struct item_head *) ((char *) LEAF + BLKH_SIZE)) +#define KEY(cache) ((struct key *) ((char *) cache + BLKH_SIZE)) +#define DC(cache) ((struct disk_child *) \ + ((char *) cache + BLKH_SIZE + KEY_SIZE * nr_item)) +/* The fsys_reiser_info block. + */ +#define INFO \ + ((struct fsys_reiser_info *) ((char *) FSYS_BUF + FSYSREISER_CACHE_SIZE)) +/* + * The journal cache. For each transaction it contains the number of + * blocks followed by the real block numbers of this transaction. + * + * If the block numbers of some transaction won't fit in this space, + * this list is stopped with a 0xffffffff marker and the remaining + * uncommitted transactions aren't cached. + */ +#define JOURNAL_START ((__u32 *) (INFO + 1)) +#define JOURNAL_END ((__u32 *) (FSYS_BUF + FSYS_BUFLEN)) + +static __inline__ int +is_power_of_two (unsigned long word) +{ + return (word & -word) == word; +} + +static int +journal_read (int block, int len, char *buffer) +{ + return devread ((INFO->journal_block + block) << INFO->blocksize_shift, + 0, len, buffer); +} + +/* Read a block from ReiserFS file system, taking the journal into + * account. If the block nr is in the journal, the block from the + * journal taken. + */ +static int +block_read (int blockNr, int start, int len, char *buffer) +{ + int transactions = INFO->journal_transactions; + int desc_block = INFO->journal_first_desc; + int journal_mask = INFO->journal_block_count - 1; + int translatedNr = blockNr; + __u32 *journal_table = JOURNAL_START; + while (transactions-- > 0) + { + int i = 0; + int j_len; + if (*journal_table != 0xffffffff) + { + /* Search for the blockNr in cached journal */ + j_len = *journal_table++; + while (i++ < j_len) + { + if (*journal_table++ == blockNr) + { + journal_table += j_len - i; + goto found; + } + } + } + else + { + /* This is the end of cached journal marker. The remaining + * transactions are still on disk. + */ + struct reiserfs_journal_desc desc; + struct reiserfs_journal_commit commit; + + if (! journal_read (desc_block, sizeof (desc), (char *) &desc)) + return 0; + + j_len = desc.j_len; + while (i < j_len && i < JOURNAL_TRANS_HALF) + if (desc.j_realblock[i++] == blockNr) + goto found; + + if (j_len >= JOURNAL_TRANS_HALF) + { + int commit_block = (desc_block + 1 + j_len) & journal_mask; + if (! journal_read (commit_block, + sizeof (commit), (char *) &commit)) + return 0; + while (i < j_len) + if (commit.j_realblock[i++ - JOURNAL_TRANS_HALF] == blockNr) + goto found; + } + } + goto not_found; + + found: + translatedNr = INFO->journal_block + ((desc_block + i) & journal_mask); +#ifdef REISERDEBUG + printf ("block_read: block %d is mapped to journal block %d.\n", + blockNr, translatedNr - INFO->journal_block); +#endif + /* We must continue the search, as this block may be overwritten + * in later transactions. + */ + not_found: + desc_block = (desc_block + 2 + j_len) & journal_mask; + } + return devread (translatedNr << INFO->blocksize_shift, start, len, buffer); +} + +/* Init the journal data structure. We try to cache as much as + * possible in the JOURNAL_START-JOURNAL_END space, but if it is full + * we can still read the rest from the disk on demand. + * + * The first number of valid transactions and the descriptor block of the + * first valid transaction are held in INFO. The transactions are all + * adjacent, but we must take care of the journal wrap around. + */ +static int +journal_init (void) +{ + unsigned int block_count = INFO->journal_block_count; + unsigned int desc_block; + unsigned int commit_block; + unsigned int next_trans_id; + struct reiserfs_journal_header header; + struct reiserfs_journal_desc desc; + struct reiserfs_journal_commit commit; + __u32 *journal_table = JOURNAL_START; + + journal_read (block_count, sizeof (header), (char *) &header); + desc_block = header.j_first_unflushed_offset; + if (desc_block >= block_count) + return 0; + + INFO->journal_first_desc = desc_block; + next_trans_id = header.j_last_flush_trans_id + 1; + +#ifdef REISERDEBUG + printf ("journal_init: last flushed %d\n", + header.j_last_flush_trans_id); +#endif + + while (1) + { + journal_read (desc_block, sizeof (desc), (char *) &desc); + if (substring (JOURNAL_DESC_MAGIC, desc.j_magic) > 0 + || desc.j_trans_id != next_trans_id + || desc.j_mount_id != header.j_mount_id) + /* no more valid transactions */ + break; + + commit_block = (desc_block + desc.j_len + 1) & (block_count - 1); + journal_read (commit_block, sizeof (commit), (char *) &commit); + if (desc.j_trans_id != commit.j_trans_id + || desc.j_len != commit.j_len) + /* no more valid transactions */ + break; + +#ifdef REISERDEBUG + printf ("Found valid transaction %d/%d at %d.\n", + desc.j_trans_id, desc.j_mount_id, desc_block); +#endif + + next_trans_id++; + if (journal_table < JOURNAL_END) + { + if ((journal_table + 1 + desc.j_len) >= JOURNAL_END) + { + /* The table is almost full; mark the end of the cached + * journal.*/ + *journal_table = 0xffffffff; + journal_table = JOURNAL_END; + } + else + { + int i; + /* Cache the length and the realblock numbers in the table. + * The block number of descriptor can easily be computed. + * and need not to be stored here. + */ + *journal_table++ = desc.j_len; + for (i = 0; i < desc.j_len && i < JOURNAL_TRANS_HALF; i++) + { + *journal_table++ = desc.j_realblock[i]; +#ifdef REISERDEBUG + printf ("block %d is in journal %d.\n", + desc.j_realblock[i], desc_block); +#endif + } + for ( ; i < desc.j_len; i++) + { + *journal_table++ = commit.j_realblock[i-JOURNAL_TRANS_HALF]; +#ifdef REISERDEBUG + printf ("block %d is in journal %d.\n", + commit.j_realblock[i-JOURNAL_TRANS_HALF], + desc_block); +#endif + } + } + } + desc_block = (commit_block + 1) & (block_count - 1); + } +#ifdef REISERDEBUG + printf ("Transaction %d/%d at %d isn't valid.\n", + desc.j_trans_id, desc.j_mount_id, desc_block); +#endif + + INFO->journal_transactions + = next_trans_id - header.j_last_flush_trans_id - 1; + return errnum == 0; +} + +/* check filesystem types and read superblock into memory buffer */ +int +reiserfs_mount (void) +{ + struct reiserfs_super_block super; + int superblock = REISERFS_DISK_OFFSET_IN_BYTES >> SECTOR_BITS; + + if (part_length < superblock + (sizeof (super) >> SECTOR_BITS) + || ! devread (superblock, 0, sizeof (struct reiserfs_super_block), + (char *) &super) + || (substring (REISER2FS_SUPER_MAGIC_STRING, super.s_magic) > 0 + && substring (REISERFS_SUPER_MAGIC_STRING, super.s_magic) > 0) + || (/* check that this is not a copy inside the journal log */ + super.s_journal_block * super.s_blocksize + <= REISERFS_DISK_OFFSET_IN_BYTES)) + { + /* Try old super block position */ + superblock = REISERFS_OLD_DISK_OFFSET_IN_BYTES >> SECTOR_BITS; + if (part_length < superblock + (sizeof (super) >> SECTOR_BITS) + || ! devread (superblock, 0, sizeof (struct reiserfs_super_block), + (char *) &super)) + return 0; + + if (substring (REISER2FS_SUPER_MAGIC_STRING, super.s_magic) > 0 + && substring (REISERFS_SUPER_MAGIC_STRING, super.s_magic) > 0) + { + /* pre journaling super block ? */ + if (substring (REISERFS_SUPER_MAGIC_STRING, + (char*) ((char *) &super + 20)) > 0) + return 0; + + super.s_blocksize = REISERFS_OLD_BLOCKSIZE; + super.s_journal_block = 0; + super.s_version = 0; + } + } + + /* check the version number. */ + if (super.s_version > REISERFS_MAX_SUPPORTED_VERSION) + return 0; + + INFO->version = super.s_version; + INFO->blocksize = super.s_blocksize; + INFO->fullblocksize_shift = log2 (super.s_blocksize); + INFO->blocksize_shift = INFO->fullblocksize_shift - SECTOR_BITS; + INFO->cached_slots = + (FSYSREISER_CACHE_SIZE >> INFO->fullblocksize_shift) - 1; + +#ifdef REISERDEBUG + printf ("reiserfs_mount: version=%d, blocksize=%d\n", + INFO->version, INFO->blocksize); +#endif /* REISERDEBUG */ + + /* Clear node cache. */ + memset (INFO->blocks, 0, sizeof (INFO->blocks)); + + if (super.s_blocksize < FSYSREISER_MIN_BLOCKSIZE + || super.s_blocksize > FSYSREISER_MAX_BLOCKSIZE + || (SECTOR_SIZE << INFO->blocksize_shift) != super.s_blocksize) + return 0; + + /* Initialize journal code. If something fails we end with zero + * journal_transactions, so we don't access the journal at all. + */ + INFO->journal_transactions = 0; + if (super.s_journal_block != 0 && super.s_journal_dev == 0) + { + INFO->journal_block = super.s_journal_block; + INFO->journal_block_count = super.s_journal_size; + if (is_power_of_two (INFO->journal_block_count)) + journal_init (); + + /* Read in super block again, maybe it is in the journal */ + block_read (superblock >> INFO->blocksize_shift, + 0, sizeof (struct reiserfs_super_block), (char *) &super); + } + + if (! block_read (super.s_root_block, 0, INFO->blocksize, (char*) ROOT)) + return 0; + + INFO->tree_depth = BLOCKHEAD (ROOT)->blk_level; + +#ifdef REISERDEBUG + printf ("root read_in: block=%d, depth=%d\n", + super.s_root_block, INFO->tree_depth); +#endif /* REISERDEBUG */ + + if (INFO->tree_depth >= MAX_HEIGHT) + return 0; + if (INFO->tree_depth == DISK_LEAF_NODE_LEVEL) + { + /* There is only one node in the whole filesystem, + * which is simultanously leaf and root */ + memcpy (LEAF, ROOT, INFO->blocksize); + } + return 1; +} + +/***************** TREE ACCESSING METHODS *****************************/ + +/* I assume you are familiar with the ReiserFS tree, if not go to + * http://www.namesys.com/content_table.html + * + * My tree node cache is organized as following + * 0 ROOT node + * 1 LEAF node (if the ROOT is also a LEAF it is copied here + * 2-n other nodes on current path from bottom to top. + * if there is not enough space in the cache, the top most are + * omitted. + * + * I have only two methods to find a key in the tree: + * search_stat(dir_id, objectid) searches for the stat entry (always + * the first entry) of an object. + * next_key() gets the next key in tree order. + * + * This means, that I can only sequential reads of files are + * efficient, but this really doesn't hurt for grub. + */ + +/* Read in the node at the current path and depth into the node cache. + * You must set INFO->blocks[depth] before. + */ +static char * +read_tree_node (unsigned int blockNr, int depth) +{ + char* cache = CACHE(depth); + int num_cached = INFO->cached_slots; + if (depth < num_cached) + { + /* This is the cached part of the path. Check if same block is + * needed. + */ + if (blockNr == INFO->blocks[depth]) + return cache; + } + else + cache = CACHE(num_cached); + +#ifdef REISERDEBUG + printf (" next read_in: block=%d (depth=%d)\n", + blockNr, depth); +#endif /* REISERDEBUG */ + if (! block_read (blockNr, 0, INFO->blocksize, cache)) + return NULL; + /* Make sure it has the right node level */ + if (BLOCKHEAD (cache)->blk_level != depth) + { + errnum = ERR_FSYS_CORRUPT; + return NULL; + } + + INFO->blocks[depth] = blockNr; + return cache; +} + +/* Get the next key, i.e. the key following the last retrieved key in + * tree order. INFO->current_ih and + * INFO->current_info are adapted accordingly. */ +static int +next_key (void) +{ + int depth; + struct item_head *ih = INFO->current_ih + 1; + char *cache; + +#ifdef REISERDEBUG + printf ("next_key:\n old ih: key %d:%d:%d:%d version:%d\n", + INFO->current_ih->ih_key.k_dir_id, + INFO->current_ih->ih_key.k_objectid, + INFO->current_ih->ih_key.u.v1.k_offset, + INFO->current_ih->ih_key.u.v1.k_uniqueness, + INFO->current_ih->ih_version); +#endif /* REISERDEBUG */ + + if (ih == &ITEMHEAD[BLOCKHEAD (LEAF)->blk_nr_item]) + { + depth = DISK_LEAF_NODE_LEVEL; + /* The last item, was the last in the leaf node. + * Read in the next block + */ + do + { + if (depth == INFO->tree_depth) + { + /* There are no more keys at all. + * Return a dummy item with MAX_KEY */ + ih = (struct item_head *) &BLOCKHEAD (LEAF)->blk_right_delim_key; + goto found; + } + depth++; +#ifdef REISERDEBUG + printf (" depth=%d, i=%d\n", depth, INFO->next_key_nr[depth]); +#endif /* REISERDEBUG */ + } + while (INFO->next_key_nr[depth] == 0); + + if (depth == INFO->tree_depth) + cache = ROOT; + else if (depth <= INFO->cached_slots) + cache = CACHE (depth); + else + { + cache = read_tree_node (INFO->blocks[depth], depth); + if (! cache) + return 0; + } + + do + { + int nr_item = BLOCKHEAD (cache)->blk_nr_item; + int key_nr = INFO->next_key_nr[depth]++; +#ifdef REISERDEBUG + printf (" depth=%d, i=%d/%d\n", depth, key_nr, nr_item); +#endif /* REISERDEBUG */ + if (key_nr == nr_item) + /* This is the last item in this block, set the next_key_nr to 0 */ + INFO->next_key_nr[depth] = 0; + + cache = read_tree_node (DC (cache)[key_nr].dc_block_number, --depth); + if (! cache) + return 0; + } + while (depth > DISK_LEAF_NODE_LEVEL); + + ih = ITEMHEAD; + } + found: + INFO->current_ih = ih; + INFO->current_item = &LEAF[ih->ih_item_location]; +#ifdef REISERDEBUG + printf (" new ih: key %d:%d:%d:%d version:%d\n", + INFO->current_ih->ih_key.k_dir_id, + INFO->current_ih->ih_key.k_objectid, + INFO->current_ih->ih_key.u.v1.k_offset, + INFO->current_ih->ih_key.u.v1.k_uniqueness, + INFO->current_ih->ih_version); +#endif /* REISERDEBUG */ + return 1; +} + +/* preconditions: reiserfs_mount already executed, therefore + * INFO block is valid + * returns: 0 if error (errnum is set), + * nonzero iff we were able to find the key successfully. + * postconditions: on a nonzero return, the current_ih and + * current_item fields describe the key that equals the + * searched key. INFO->next_key contains the next key after + * the searched key. + * side effects: messes around with the cache. + */ +static int +search_stat (__u32 dir_id, __u32 objectid) +{ + char *cache; + int depth; + int nr_item; + int i; + struct item_head *ih; +#ifdef REISERDEBUG + printf ("search_stat:\n key %d:%d:0:0\n", dir_id, objectid); +#endif /* REISERDEBUG */ + + depth = INFO->tree_depth; + cache = ROOT; + + while (depth > DISK_LEAF_NODE_LEVEL) + { + struct key *key; + nr_item = BLOCKHEAD (cache)->blk_nr_item; + + key = KEY (cache); + + for (i = 0; i < nr_item; i++) + { + if (key->k_dir_id > dir_id + || (key->k_dir_id == dir_id + && (key->k_objectid > objectid + || (key->k_objectid == objectid + && (key->u.v1.k_offset + | key->u.v1.k_uniqueness) > 0)))) + break; + key++; + } + +#ifdef REISERDEBUG + printf (" depth=%d, i=%d/%d\n", depth, i, nr_item); +#endif /* REISERDEBUG */ + INFO->next_key_nr[depth] = (i == nr_item) ? 0 : i+1; + cache = read_tree_node (DC (cache)[i].dc_block_number, --depth); + if (! cache) + return 0; + } + + /* cache == LEAF */ + nr_item = BLOCKHEAD (LEAF)->blk_nr_item; + ih = ITEMHEAD; + for (i = 0; i < nr_item; i++) + { + if (ih->ih_key.k_dir_id == dir_id + && ih->ih_key.k_objectid == objectid + && ih->ih_key.u.v1.k_offset == 0 + && ih->ih_key.u.v1.k_uniqueness == 0) + { +#ifdef REISERDEBUG + printf (" depth=%d, i=%d/%d\n", depth, i, nr_item); +#endif /* REISERDEBUG */ + INFO->current_ih = ih; + INFO->current_item = &LEAF[ih->ih_item_location]; + return 1; + } + ih++; + } + errnum = ERR_FSYS_CORRUPT; + return 0; +} + +int +reiserfs_read (char *buf, int len) +{ + unsigned int blocksize; + unsigned int offset; + unsigned int to_read; + char *prev_buf = buf; + +#ifdef REISERDEBUG + printf ("reiserfs_read: filepos=%d len=%d, offset=%x:%x\n", + filepos, len, (__u64) IH_KEY_OFFSET (INFO->current_ih) - 1); +#endif /* REISERDEBUG */ + + if (INFO->current_ih->ih_key.k_objectid != INFO->fileinfo.k_objectid + || IH_KEY_OFFSET (INFO->current_ih) > filepos + 1) + { + search_stat (INFO->fileinfo.k_dir_id, INFO->fileinfo.k_objectid); + goto get_next_key; + } + + while (! errnum) + { + if (INFO->current_ih->ih_key.k_objectid != INFO->fileinfo.k_objectid) + break; + + offset = filepos - IH_KEY_OFFSET (INFO->current_ih) + 1; + blocksize = INFO->current_ih->ih_item_len; + +#ifdef REISERDEBUG + printf (" loop: filepos=%d len=%d, offset=%d blocksize=%d\n", + filepos, len, offset, blocksize); +#endif /* REISERDEBUG */ + + if (IH_KEY_ISTYPE(INFO->current_ih, TYPE_DIRECT) + && offset < blocksize) + { +#ifdef REISERDEBUG + printf ("direct_read: offset=%d, blocksize=%d\n", + offset, blocksize); +#endif /* REISERDEBUG */ + to_read = blocksize - offset; + if (to_read > len) + to_read = len; + + if (disk_read_hook != NULL) + { + disk_read_func = disk_read_hook; + + block_read (INFO->blocks[DISK_LEAF_NODE_LEVEL], + (INFO->current_item - LEAF + offset), to_read, buf); + + disk_read_func = NULL; + } + else + memcpy (buf, INFO->current_item + offset, to_read); + goto update_buf_len; + } + else if (IH_KEY_ISTYPE(INFO->current_ih, TYPE_INDIRECT)) + { + blocksize = (blocksize >> 2) << INFO->fullblocksize_shift; +#ifdef REISERDEBUG + printf ("indirect_read: offset=%d, blocksize=%d\n", + offset, blocksize); +#endif /* REISERDEBUG */ + + while (offset < blocksize) + { + __u32 blocknr = ((__u32 *) INFO->current_item) + [offset >> INFO->fullblocksize_shift]; + int blk_offset = offset & (INFO->blocksize-1); + + to_read = INFO->blocksize - blk_offset; + if (to_read > len) + to_read = len; + + disk_read_func = disk_read_hook; + + /* Journal is only for meta data. Data blocks can be read + * directly without using block_read + */ + devread (blocknr << INFO->blocksize_shift, + blk_offset, to_read, buf); + + disk_read_func = NULL; + update_buf_len: + len -= to_read; + buf += to_read; + offset += to_read; + filepos += to_read; + if (len == 0) + goto done; + } + } + get_next_key: + next_key (); + } + done: + return errnum ? 0 : buf - prev_buf; +} + + +/* preconditions: reiserfs_mount already executed, therefore + * INFO block is valid + * returns: 0 if error, nonzero iff we were able to find the file successfully + * postconditions: on a nonzero return, INFO->fileinfo contains the info + * of the file we were trying to look up, filepos is 0 and filemax is + * the size of the file. + */ +int +reiserfs_dir (char *dirname) +{ + struct reiserfs_de_head *de_head; + char *rest, ch; + __u32 dir_id, objectid, parent_dir_id = 0, parent_objectid = 0; +#ifndef STAGE1_5 + int do_possibilities = 0; +#endif /* ! STAGE1_5 */ + char linkbuf[PATH_MAX]; /* buffer for following symbolic links */ + int link_count = 0; + int mode; + + dir_id = REISERFS_ROOT_PARENT_OBJECTID; + objectid = REISERFS_ROOT_OBJECTID; + + while (1) + { +#ifdef REISERDEBUG + printf ("dirname=%s\n", dirname); +#endif /* REISERDEBUG */ + + /* Search for the stat info first. */ + if (! search_stat (dir_id, objectid)) + return 0; + +#ifdef REISERDEBUG + printf ("sd_mode=%x sd_size=%d\n", + ((struct stat_data *) INFO->current_item)->sd_mode, + ((struct stat_data *) INFO->current_item)->sd_size); +#endif /* REISERDEBUG */ + + mode = ((struct stat_data *) INFO->current_item)->sd_mode; + + /* If we've got a symbolic link, then chase it. */ + if (S_ISLNK (mode)) + { + int len; + if (++link_count > MAX_LINK_COUNT) + { + errnum = ERR_SYMLINK_LOOP; + return 0; + } + + /* Get the symlink size. */ + filemax = ((struct stat_data *) INFO->current_item)->sd_size; + + /* Find out how long our remaining name is. */ + len = 0; + while (dirname[len] && !isspace (dirname[len])) + len++; + + if (filemax + len > sizeof (linkbuf) - 1) + { + errnum = ERR_FILELENGTH; + return 0; + } + + /* Copy the remaining name to the end of the symlink data. + Note that DIRNAME and LINKBUF may overlap! */ + grub_memmove (linkbuf + filemax, dirname, len+1); + + INFO->fileinfo.k_dir_id = dir_id; + INFO->fileinfo.k_objectid = objectid; + filepos = 0; + if (! next_key () + || reiserfs_read (linkbuf, filemax) != filemax) + { + if (! errnum) + errnum = ERR_FSYS_CORRUPT; + return 0; + } + +#ifdef REISERDEBUG + printf ("symlink=%s\n", linkbuf); +#endif /* REISERDEBUG */ + + dirname = linkbuf; + if (*dirname == '/') + { + /* It's an absolute link, so look it up in root. */ + dir_id = REISERFS_ROOT_PARENT_OBJECTID; + objectid = REISERFS_ROOT_OBJECTID; + } + else + { + /* Relative, so look it up in our parent directory. */ + dir_id = parent_dir_id; + objectid = parent_objectid; + } + + /* Now lookup the new name. */ + continue; + } + + /* if we have a real file (and we're not just printing possibilities), + then this is where we want to exit */ + + if (! *dirname || isspace (*dirname)) + { + if (! S_ISREG (mode)) + { + errnum = ERR_BAD_FILETYPE; + return 0; + } + + filepos = 0; + filemax = ((struct stat_data *) INFO->current_item)->sd_size; + + /* If this is a new stat data and size is > 4GB set filemax to + * maximum + */ + if (INFO->current_ih->ih_version == ITEM_VERSION_2 + && ((struct stat_data *) INFO->current_item)->sd_size_hi > 0) + filemax = 0xffffffff; + + INFO->fileinfo.k_dir_id = dir_id; + INFO->fileinfo.k_objectid = objectid; + return next_key (); + } + + /* continue with the file/directory name interpretation */ + while (*dirname == '/') + dirname++; + if (! S_ISDIR (mode)) + { + errnum = ERR_BAD_FILETYPE; + return 0; + } + for (rest = dirname; (ch = *rest) && ! isspace (ch) && ch != '/'; rest++); + *rest = 0; + +# ifndef STAGE1_5 + if (print_possibilities && ch != '/') + do_possibilities = 1; +# endif /* ! STAGE1_5 */ + + while (1) + { + char *name_end; + int num_entries; + + if (! next_key ()) + return 0; +#ifdef REISERDEBUG + printf ("ih: key %d:%d:%d:%d version:%d\n", + INFO->current_ih->ih_key.k_dir_id, + INFO->current_ih->ih_key.k_objectid, + INFO->current_ih->ih_key.u.v1.k_offset, + INFO->current_ih->ih_key.u.v1.k_uniqueness, + INFO->current_ih->ih_version); +#endif /* REISERDEBUG */ + + if (INFO->current_ih->ih_key.k_objectid != objectid) + break; + + name_end = INFO->current_item + INFO->current_ih->ih_item_len; + de_head = (struct reiserfs_de_head *) INFO->current_item; + num_entries = INFO->current_ih->u.ih_entry_count; + while (num_entries > 0) + { + char *filename = INFO->current_item + de_head->deh_location; + char tmp = *name_end; + if ((de_head->deh_state & DEH_Visible)) + { + int cmp; + /* Directory names in ReiserFS are not null + * terminated. We write a temporary 0 behind it. + * NOTE: that this may overwrite the first block in + * the tree cache. That doesn't hurt as long as we + * don't call next_key () in between. + */ + *name_end = 0; + cmp = substring (dirname, filename); + *name_end = tmp; +# ifndef STAGE1_5 + if (do_possibilities) + { + if (cmp <= 0) + { + if (print_possibilities > 0) + print_possibilities = -print_possibilities; + *name_end = 0; + print_a_completion (filename); + *name_end = tmp; + } + } + else +# endif /* ! STAGE1_5 */ + if (cmp == 0) + goto found; + } + /* The beginning of this name marks the end of the next name. + */ + name_end = filename; + de_head++; + num_entries--; + } + } + +# ifndef STAGE1_5 + if (print_possibilities < 0) + return 1; +# endif /* ! STAGE1_5 */ + + errnum = ERR_FILE_NOT_FOUND; + *rest = ch; + return 0; + + found: + + *rest = ch; + dirname = rest; + + parent_dir_id = dir_id; + parent_objectid = objectid; + dir_id = de_head->deh_dir_id; + objectid = de_head->deh_objectid; + } +} + +int +reiserfs_embed (int *start_sector, int needed_sectors) +{ + struct reiserfs_super_block super; + int num_sectors; + + if (! devread (REISERFS_DISK_OFFSET_IN_BYTES >> SECTOR_BITS, 0, + sizeof (struct reiserfs_super_block), (char *) &super)) + return 0; + + *start_sector = 1; /* reserve first sector for stage1 */ + if ((substring (REISERFS_SUPER_MAGIC_STRING, super.s_magic) <= 0 + || substring (REISER2FS_SUPER_MAGIC_STRING, super.s_magic) <= 0) + && (/* check that this is not a super block copy inside + * the journal log */ + super.s_journal_block * super.s_blocksize + > REISERFS_DISK_OFFSET_IN_BYTES)) + num_sectors = (REISERFS_DISK_OFFSET_IN_BYTES >> SECTOR_BITS) - 1; + else + num_sectors = (REISERFS_OLD_DISK_OFFSET_IN_BYTES >> SECTOR_BITS) - 1; + + return (needed_sectors <= num_sectors); +} +#endif /* FSYS_REISERFS */