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reiserfsprogs/reiserfscore/node_formats.c
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/*
* Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
*/
#include "includes.h"
int correct_direct_item_offset (__u64 offset, int format) {
if (format == KEY_FORMAT_2) {
return (offset && ((offset - 1) % 8 == 0));
} else {
return (offset);
}
return 0;
}
/* this only checks block header and item head array (ih_location-s
and ih_item_len-s). Item internals are not checked */
static int does_node_look_like_a_leaf (char * buf, int blocksize)
{
struct block_head * blkh;
struct item_head * ih;
int used_space;
int prev_location;
int i;
int nr;
blkh = (struct block_head *)buf;
if (!is_leaf_block_head (buf))
return 0;
nr = get_blkh_nr_items (blkh);
if (nr < 0 || nr > ((blocksize - BLKH_SIZE) / (IH_SIZE + MIN_ITEM_LEN)))
/* item number is too big or too small */
return 0;
ih = (struct item_head *)(buf + BLKH_SIZE) + nr - 1;
used_space = BLKH_SIZE + IH_SIZE * nr + (blocksize - (nr ? get_ih_location (ih) : blocksize));
if (used_space != blocksize - get_blkh_free_space (blkh))
/* free space does not match to calculated amount of use space */
return 0;
// FIXME: it is_leaf will hit performance too much - we may have
// return 1 here
/* check tables of item heads */
ih = (struct item_head *)(buf + BLKH_SIZE);
prev_location = blocksize;
for (i = 0; i < nr; i ++, ih ++) {
/* items of zero length are allowed - they may exist for short time
during balancing */
if (get_ih_location (ih) > blocksize || get_ih_location (ih) < IH_SIZE * nr)
return 0;
if (/*ih_item_len (ih) < 1 ||*/ get_ih_item_len (ih) > MAX_ITEM_LEN (blocksize))
return 0;
if (prev_location - get_ih_location (ih) != get_ih_item_len (ih))
return 0;
prev_location = get_ih_location (ih);
}
// one may imagine much more checks
return 1;
}
/* check ih_item_len and ih_location. Should be useful when block head is
corrupted */
int does_node_have_ih_array (char * buf, int blocksize)
{
struct item_head * ih;
int prev_location;
int nr;
/* look at the table of item head */
prev_location = blocksize;
ih = (struct item_head *)(buf + BLKH_SIZE);
nr = 0;
while (1) {
if (get_ih_location (ih) + get_ih_item_len (ih) != prev_location)
break;
prev_location = get_ih_location (ih);
ih ++;
nr ++;
}
if (nr < 2)
return 0;
return nr;
}
/* returns 1 if buf looks like an internal node, 0 otherwise */
static int is_correct_internal (char * buf, int blocksize)
{
struct block_head * blkh;
int nr;
int used_space;
blkh = (struct block_head *)buf;
if (!is_internal_block_head (buf))
return 0;
nr = get_blkh_nr_items (blkh);
if (nr > (blocksize - BLKH_SIZE - DC_SIZE) / (KEY_SIZE + DC_SIZE))
/* for internal which is not root we might check min number of keys */
return 0;
used_space = BLKH_SIZE + KEY_SIZE * nr + DC_SIZE * (nr + 1);
if (used_space != blocksize - get_blkh_free_space (blkh))
return 0;
// one may imagine much more checks
return 1;
}
// make sure that bh contains formatted node of reiserfs tree of
// 'level'-th level
int is_tree_node (struct buffer_head * bh, int level)
{
if (B_LEVEL (bh) != level)
return 0;
if (is_leaf_node (bh))
return does_node_look_like_a_leaf (bh->b_data, bh->b_size);
return is_correct_internal (bh->b_data, bh->b_size);
}
static int is_desc_block (char * buf, unsigned long buf_size)
{
if (!memcmp(buf + buf_size - 12, JOURNAL_DESC_MAGIC, 8) &&
//get_jdesc_len (desc) > 0)
le32_to_cpu(*((__u32*)(buf + 4))) > 0)
return 1;
return 0;
}
int is_reiserfs_3_5_magic_string (struct reiserfs_super_block * rs)
{
return (!strncmp (rs->s_v1.s_magic, REISERFS_3_5_SUPER_MAGIC_STRING,
strlen ( REISERFS_3_5_SUPER_MAGIC_STRING)));
}
int is_reiserfs_3_6_magic_string (struct reiserfs_super_block * rs)
{
return (!strncmp (rs->s_v1.s_magic, REISERFS_3_6_SUPER_MAGIC_STRING,
strlen ( REISERFS_3_6_SUPER_MAGIC_STRING)));
}
int is_reiserfs_jr_magic_string (struct reiserfs_super_block * rs)
{
return (!strncmp (rs->s_v1.s_magic, REISERFS_JR_SUPER_MAGIC_STRING,
strlen ( REISERFS_JR_SUPER_MAGIC_STRING)));
}
int is_any_reiserfs_magic_string (struct reiserfs_super_block * rs)
{
if (is_reiserfs_3_5_magic_string (rs) ||
is_reiserfs_3_6_magic_string (rs) ||
is_reiserfs_jr_magic_string (rs))
return 1;
return 0;
}
int get_reiserfs_format (struct reiserfs_super_block * sb)
{
/* after conversion to 3.6 format we change magic correctly,
but do not change sb_format. When we create non-standard journal
field format in sb get adjusted correctly. Thereby, for standard
journal we should rely on magic and for non-standard - on format */
if (is_reiserfs_3_5_magic_string (sb) ||
(is_reiserfs_jr_magic_string (sb) &&
get_sb_version (sb) == REISERFS_FORMAT_3_5))
return REISERFS_FORMAT_3_5;
if (is_reiserfs_3_6_magic_string (sb) ||
(is_reiserfs_jr_magic_string (sb) &&
get_sb_version (sb) == REISERFS_FORMAT_3_6))
return REISERFS_FORMAT_3_6;
return REISERFS_FORMAT_UNKNOWN;
}
int reiserfs_super_block_size (struct reiserfs_super_block * sb)
{
switch (get_reiserfs_format (sb)) {
case REISERFS_FORMAT_3_5:
return SB_SIZE_V1;
case REISERFS_FORMAT_3_6:
return SB_SIZE;
}
reiserfs_panic ("Unknown format found");
return 0;
}
#if 0
/* returns code of 0 - here means 3.5 format,
2 - either pure 3.6 or converted 3.5
3 - journal-relocated 3.6*/
int magic_2_version (struct reiserfs_super_block * rs)
{
int ret;
ret = 0;
if (is_reiser2fs_magic_string (rs))
ret = REISERFS_VERSION_2 ;
else if (is_reiser2fs_jr_magic_string (rs))
ret = REISERFS_VERSION_3;
else if (is_reiserfs_magic_string (rs))
ret = REISERFS_VERSION_1;
else
reiserfs_panic ("magic_2_version: unknown magic string found");
return ret;
}
#endif
/* this one had signature in different place of the super_block
structure */
int is_prejournaled_reiserfs (struct reiserfs_super_block * rs)
{
return (!strncmp((char*)rs + REISERFS_SUPER_MAGIC_STRING_OFFSET_NJ,
REISERFS_3_5_SUPER_MAGIC_STRING,
strlen(REISERFS_3_5_SUPER_MAGIC_STRING)));
}
int does_look_like_super_block (struct reiserfs_super_block * sb, int blocksize) {
if (is_any_reiserfs_magic_string (sb) && blocksize == get_sb_block_size (sb))
return 1;
return 0;
}
/* returns code of reiserfs metadata block (leaf, internal, super
block, journal descriptor), unformatted */
int who_is_this (char * buf, int blocksize)
{
/* super block? */
if (does_look_like_super_block ((void *)buf, blocksize))
return THE_SUPER;
if (does_node_look_like_a_leaf (buf, blocksize))
/* block head and item head array seem matching (node level, free
space, item number, item locations and length) */
return THE_LEAF;
if (does_node_have_ih_array (buf, blocksize)) {
/* item header array found */
return HAS_IH_ARRAY;
}
if (is_correct_internal (buf, blocksize))
return THE_INTERNAL;
/* journal descriptor block? */
if (is_desc_block (buf, blocksize))
return THE_JDESC;
/* contents of buf does not look like reiserfs metadata. Bitmaps
are possible here */
return THE_UNKNOWN;
}
char * which_block (int code)
{
static char * leaf = "leaf";
static char * broken_leaf = "leaf w/o block head";
static char * internal = "internal";
static char * other = "unknown";
switch (code) {
case THE_LEAF:
return leaf;
case HAS_IH_ARRAY:
return broken_leaf;
case THE_INTERNAL:
return internal;
}
return other;
}
/** */
int block_of_journal (reiserfs_filsys_t * fs, unsigned long block)
{
if (!is_reiserfs_jr_magic_string (fs->fs_ondisk_sb)) {
/* standard journal */
if (block >= get_journal_start_must (fs) &&
block <= get_journal_start_must (fs) + get_jp_journal_size (sb_jp (fs->fs_ondisk_sb)))
return 1;
return 0;
}
if (get_sb_reserved_for_journal (fs->fs_ondisk_sb))
/* there is space reserved for the journal on the host device */
if (block >= get_journal_start_must (fs) &&
block < get_journal_start_must (fs) + get_sb_reserved_for_journal (fs->fs_ondisk_sb))
return 1;
return 0;
}
int block_of_bitmap (reiserfs_filsys_t * fs, unsigned long block)
{
if (spread_bitmaps (fs)) {
if (!(block % (fs->fs_blocksize * 8)))
/* bitmap block */
return 1;
return (block == (REISERFS_DISK_OFFSET_IN_BYTES / fs->fs_blocksize + 1)) ;
} else {
/* bitmap in */
if (block > 2 && block < 3 + get_sb_bmap_nr (fs->fs_ondisk_sb))
return 1;
return 0;
}
return 0;
}
/* check whether 'block' can be pointed to by an indirect item */
int not_data_block (reiserfs_filsys_t * fs, unsigned long block)
{
if (block_of_bitmap (fs, block))
/* it is one of bitmap blocks */
return 1;
if (block > 32768)
return 0;
if (block_of_journal (fs, block))
/* block of journal area */
return 1;
if (block <= fs->fs_super_bh->b_blocknr)
/* either super block or a block from skipped area at the
beginning of filesystem */
return 1;
return 0;
}
/* check whether 'block' can be logged */
int not_journalable (reiserfs_filsys_t * fs, unsigned long block)
{
/* we should not update SB with journal copy during fsck */
if (block < fs->fs_super_bh->b_blocknr)
return 1;
if (block_of_journal (fs, block))
return 1;
if (block >= get_sb_block_count (fs->fs_ondisk_sb))
return 1;
return 0;
}
// in reiserfs version 0 (undistributed bitmap)
// FIXME: what if number of bitmaps is 15?
int get_journal_old_start_must (reiserfs_filsys_t * fs)
{
return (REISERFS_OLD_DISK_OFFSET_IN_BYTES / fs->fs_blocksize) + 1 + get_sb_bmap_nr (fs->fs_ondisk_sb);
}
int get_journal_new_start_must (reiserfs_filsys_t * fs)
{
return (REISERFS_DISK_OFFSET_IN_BYTES / fs->fs_blocksize) + 2;
}
int get_journal_start_must (reiserfs_filsys_t * fs) {
// if (fs->fs_super_bh->b_size == 4096 && fs->fs_super_bh->b_blocknr == 2)
if (is_old_sb_location (fs->fs_super_bh->b_blocknr, fs->fs_blocksize))
return get_journal_old_start_must (fs);
return get_journal_new_start_must (fs);
}
__u64 get_bytes_number (struct item_head * ih, int blocksize)
{
switch (get_type (&ih->ih_key)) {
case TYPE_DIRECT:
return get_ih_item_len (ih);
case TYPE_INDIRECT:
return I_UNFM_NUM(ih) * blocksize;// - get_ih_free_space (ih);
case TYPE_STAT_DATA:
case TYPE_DIRENTRY:
return 0;
}
reiserfs_warning (stderr, "get_bytes_number: called for wrong type of item %h", ih);
return 0;
}
int check_item_f (reiserfs_filsys_t * fs, struct item_head * ih, char * item);
#if 0
/* look at the 16 byte and try to find: does it look like a reiserfs
key. Returns 0 if something looks broken in the key, 1 otherwise */
static int does_key_look_correct (reiserfs_filsys_t * fs, struct key * key)
{
int type;
if (key->k_dir_id == key->k_objectid ||
!key->k_dir_id || key->k_objectid < 2)
/* k_dir_id and k_objectid must be different, and > 0 */
return 0;
if (key->u.k_offset_v1.k_offset == 0 &&
key->u.k_offset_v1.k_uniqueness == 0)
/* looks like a stat data */
return 1;
if (!key->u.k_offset_v1.k_offset ||
!key->u.k_offset_v1.k_uniqueness)
/* these should be either both 0 or both !0 */
return 0;
type = key->u.k_offset_v2.k_type;
if (key->u.k_offset_v1.k_uniqueness == 500)
/* looks like a key of directory entry */
return (type == 0) ? 1 : 0;
if (type == 15) {
/* looks like old key of */
if (key->u.k_offset_v1.k_uniqueness == 0xffffffff) {
/* direct item. Check offset */
if (key->u.k_offset_v1.k_offset >= fs->s_blocksize * 4 + 1)
/* fixme: this could be more accurate */
return 0;
return 1;
}
if (key->u.k_offset_v1.k_uniqueness == 0xfffffffe) {
/* indirect item. Check offset */
if (key->u.k_offset_v1.k_offset % fs->s_blocksize != 1)
return 0;
return 1;
}
return 0;
}
/* there should be a new key of indirect or direct item */
if (type == TYPE_DIRECT) {
/* check offset */
if (key->u.k_offset_v2.k_offset >= fs->s_blocksize * 4 + 1) /* fixme*/
/* fixme: this could be more accurate */
return 0;
if ((key->u.k_offset_v2.k_offset - 1) % 8 != 0)
/* "new" direct items get split on the boundary of 8 byte */
return 0;
return 1;
}
if (type == TYPE_INDIRECT) {
/* check offset */
if ((key->u.k_offset_v2.k_offset % fs->s_blocksize) != 1)
return 0;
return 1;
}
return 0;
}
#endif
/* ih_key, ih_location and ih_item_len seem correct, check other fields */
static int does_ih_look_correct (struct item_head * ih)
{
int ih_key_format;
int key_key_format;
/* key format from item_head */
ih_key_format = get_ih_key_format (ih);
if (ih_key_format != KEY_FORMAT_1 && ih_key_format != KEY_FORMAT_2)
return 0;
/* key format calculated on key */
key_key_format = key_format (&ih->ih_key);
if (is_stat_data_ih (ih)) {
/* for stat data we can not find key format from a key itself, so look at
the item length */
if (get_ih_item_len (ih) == SD_SIZE)
key_key_format = KEY_FORMAT_2;
else if (get_ih_item_len (ih) == SD_V1_SIZE)
key_key_format = KEY_FORMAT_1;
else
return 0;
}
if (key_key_format != ih_key_format)
return 0;
/* we do not check ih_format.fsck_need as fsck might change it. So,
debugreiserfs -p will have to dump it */
return 1;
}
/* check item length, ih_free_space for pure 3.5 format, unformatted node
pointers */
static int is_bad_indirect (reiserfs_filsys_t * fs, struct item_head * ih, char * item,
check_unfm_func_t check_unfm_func)
{
int i;
__u32 * ind = (__u32 *)item;
if (get_ih_item_len (ih) % UNFM_P_SIZE)
return 1;
for (i = 0; i < I_UNFM_NUM (ih); i ++) {
if (!ind [i])
continue;
if (check_unfm_func && check_unfm_func (fs, le32_to_cpu(ind [i])))
return 1;
}
if (fs->fs_format == REISERFS_FORMAT_3_5) {
/* check ih_free_space for 3.5 format only */
if (get_ih_free_space (ih) > fs->fs_blocksize - 1)
return 1;
}
return 0;
}
static const struct {
hashf_t func;
char * name;
} hashes[] = {{0, "not set"},
{keyed_hash, "\"tea\""},
{yura_hash, "\"rupasov\""},
{r5_hash, "\"r5\""}};
#define HASH_AMOUNT (sizeof (hashes) / sizeof (hashes [0]))
int known_hashes (void)
{
return HASH_AMOUNT;
}
#define good_name(hashfn,name,namelen,deh_offset) \
(GET_HASH_VALUE ((hashfn) (name, namelen)) == GET_HASH_VALUE (deh_offset))
/* this also sets hash function */
int is_properly_hashed (reiserfs_filsys_t * fs,
char * name, int namelen, __u32 offset)
{
int i;
if (namelen == 1 && name[0] == '.') {
if (offset == DOT_OFFSET)
return 1;
return 0;
}
if (namelen == 2 && name[0] == '.' && name[1] == '.') {
if (offset == DOT_DOT_OFFSET)
return 1;
return 0;
}
if (hash_func_is_unknown (fs)) {
/* try to find what hash function the name is sorted with */
for (i = 1; i < HASH_AMOUNT; i ++) {
if (good_name (hashes [i].func, name, namelen, offset)) {
if (!hash_func_is_unknown (fs)) {
/* two or more hash functions give the same value for this
name */
fprintf (stderr, "Detecting hash code: could not detect hash with name \"%.*s\"\n",
namelen, name);
reiserfs_hash (fs) = 0;
return 1;
}
/* set hash function */
reiserfs_hash(fs) = hashes [i].func;
}
}
if (hash_func_is_unknown (fs)) {
return 0;
}
}
if (good_name (reiserfs_hash(fs), name, namelen, offset))
return 1;
#if 0
fprintf (stderr, "is_properly_hashed: namelen %d, name \"%s\", offset %u, hash %u\n",
namelen, name_from_entry (name, namelen), GET_HASH_VALUE (offset),
GET_HASH_VALUE (reiserfs_hash(fs) (name, namelen)));
/* we could also check whether more than one hash function match on the
name */
for (i = 1; i < sizeof (hashes) / sizeof (hashes [0]); i ++) {
if (i == g_real_hash)
continue;
if (good_name (hashes[i], name, namelen, deh_offset)) {
die ("bad_hash: at least two hashes got screwed up with this name: \"%s\"",
bad_name (name, namelen));
}
}
#endif
return 0;
}
int find_hash_in_use (char * name, int namelen, __u32 hash_value_masked, int code_to_try_first)
{
int i;
if (!namelen || !name[0])
return UNSET_HASH;
if (code_to_try_first) {
if (hash_value_masked == GET_HASH_VALUE (hashes [code_to_try_first].func (name, namelen)))
return code_to_try_first;
}
for (i = 1; i < HASH_AMOUNT; i ++) {
if (i == code_to_try_first)
continue;
if (hash_value_masked == GET_HASH_VALUE (hashes [i].func (name, namelen)))
return i;
}
/* not matching hash found */
return UNSET_HASH;
}
char * code2name (int code)
{
if (code >= HASH_AMOUNT || code < 0)
return 0;
return hashes [code].name;
}
int func2code (hashf_t func)
{
int i;
for (i = 0; i < HASH_AMOUNT; i ++)
if (func == hashes [i].func)
return i;
reiserfs_panic ("func2code: no hashes matches this function\n");
return 0;
}
hashf_t code2func (int code)
{
if (code >= HASH_AMOUNT) {
reiserfs_warning (stderr, "code2func: wrong hash code %d.\n"
"Using default %s hash function\n", code,
code2name (DEFAULT_HASH));
code = DEFAULT_HASH;
}
return hashes [code].func;
}
hashf_t name2func (char * hash)
{
int i;
for (i = 0; i < HASH_AMOUNT; i ++)
if (!strcmp (hash, hashes [i].name))
return hashes [i].func;
return 0;
}
int dir_entry_bad_location (struct reiserfs_de_head * deh, struct item_head * ih, int first)
{
if (get_deh_location (deh) < DEH_SIZE * get_ih_entry_count (ih))
return 1;
if (get_deh_location (deh) >= get_ih_item_len (ih))
return 1;
if (!first && get_deh_location (deh) >= get_deh_location (deh - 1))
return 1;
return 0;
}
/* the only corruption which is not considered fatal - is hash mismatching. If
bad_dir is set - directory item having such names is considered bad */
static int is_bad_directory (reiserfs_filsys_t * fs, struct item_head * ih, char * item,
int bad_dir)
{
int i;
int namelen;
struct reiserfs_de_head * deh = (struct reiserfs_de_head *)item;
__u32 prev_offset = 0;
__u16 prev_location = get_ih_item_len (ih);
for (i = 0; i < get_ih_entry_count (ih); i ++, deh ++) {
if (get_deh_location (deh) >= prev_location)
return 1;
prev_location = get_deh_location (deh);
namelen = name_in_entry_length (ih, deh, i);
if (namelen > REISERFS_MAX_NAME_LEN (fs->fs_blocksize)) {
return 1;
}
if (get_deh_offset (deh) <= prev_offset)
return 1;
prev_offset = get_deh_offset (deh);
/* check hash value */
if (!is_properly_hashed (fs, item + prev_location, namelen, prev_offset)) {
if (bad_dir)
/* make is_bad_leaf to not insert whole leaf. Node will be
marked not-insertable and put into tree item by item in
pass 2 */
return 1;
}
}
return 0;
}
/* used by debugreisrefs -p only yet */
int is_it_bad_item (reiserfs_filsys_t * fs, struct item_head * ih, char * item,
check_unfm_func_t check_unfm, int bad_dir)
{
int retval;
/*
if (!does_key_look_correct (fs, &ih->ih_key))
return 1;
if (!does_ih_look_correct (ih))
return 1;
*/
if (!does_ih_look_correct (ih))
return 1;
if (is_stat_data_ih (ih) || is_direct_ih (ih))
return 0;
if (is_direntry_ih (ih)) {
retval = is_bad_directory (fs, ih, item, bad_dir);
/*
if (retval)
reiserfs_warning (stderr, "is_bad_directory %H\n", ih);*/
return retval;
}
if (is_indirect_ih (ih)) {
retval = is_bad_indirect (fs, ih, item, check_unfm);
/*
if (retval)
reiserfs_warning (stderr, "is_bad_indirect %H\n", ih);*/
return retval;
}
return 1;
}
/* prepare new or old stat data for the new directory */
void make_dir_stat_data (int blocksize, int key_format,
__u32 dirid, __u32 objectid,
struct item_head * ih, void * sd)
{
memset (ih, 0, IH_SIZE);
set_key_dirid (&ih->ih_key, dirid);
set_key_objectid (&ih->ih_key, objectid);
set_key_offset_v1 (&ih->ih_key, SD_OFFSET);
set_key_uniqueness (&ih->ih_key, 0);
set_ih_key_format (ih, key_format);
set_ih_free_space (ih, MAX_US_INT);
if (key_format == KEY_FORMAT_2) {
struct stat_data *sd_v2 = (struct stat_data *)sd;
set_ih_item_len (ih, SD_SIZE);
set_sd_v2_mode (sd_v2, S_IFDIR + 0755);
set_sd_v2_nlink (sd_v2, 2);
set_sd_v2_uid (sd_v2, 0);
set_sd_v2_gid (sd_v2, 0);
set_sd_v2_size (sd_v2, EMPTY_DIR_SIZE);
set_sd_v2_atime (sd_v2, time(NULL));
sd_v2->sd_ctime = sd_v2->sd_mtime = sd_v2->sd_atime; /* all le */
set_sd_v2_rdev (sd_v2, 0);
set_sd_v2_blocks (sd_v2, dir_size2st_blocks (EMPTY_DIR_SIZE));
}else{
struct stat_data_v1 *sd_v1 = (struct stat_data_v1 *)sd;
set_ih_item_len (ih, SD_V1_SIZE);
set_sd_v1_mode(sd_v1, S_IFDIR + 0755);
set_sd_v1_nlink(sd_v1, 2);
set_sd_v1_uid (sd_v1, 0);
set_sd_v1_gid (sd_v1, 0);
set_sd_v1_size(sd_v1, EMPTY_DIR_SIZE_V1);
set_sd_v1_atime(sd_v1, time(NULL));
sd_v1->sd_ctime = sd_v1->sd_mtime = sd_v1->sd_atime; /* all le */
set_sd_v1_blocks(sd_v1, dir_size2st_blocks(EMPTY_DIR_SIZE_V1));
set_sd_v1_first_direct_byte(sd_v1, NO_BYTES_IN_DIRECT_ITEM);
}
}
static void _empty_dir_item (int format, char * body, __u32 dirid, __u32 objid,
__u32 par_dirid, __u32 par_objid)
{
struct reiserfs_de_head * deh;
__u16 state;
memset (body, 0, (format == KEY_FORMAT_2 ? EMPTY_DIR_SIZE : EMPTY_DIR_SIZE_V1));
deh = (struct reiserfs_de_head *)body;
/* direntry header of "." */
set_deh_offset (deh, DOT_OFFSET);
set_deh_dirid (deh, dirid);
set_deh_objectid (deh, objid);
state = (1 << DEH_Visible2);
set_deh_state (deh, state);
/* direntry header of ".." */
set_deh_offset (deh + 1, DOT_DOT_OFFSET);
/* key of ".." for the root directory */
set_deh_dirid (deh + 1, par_dirid);
set_deh_objectid (deh + 1, par_objid);
set_deh_state (deh + 1, state);
if (format == KEY_FORMAT_2) {
set_deh_location (deh, EMPTY_DIR_SIZE - ROUND_UP (strlen (".")));
set_deh_location (deh + 1, get_deh_location (deh) - ROUND_UP (strlen ("..")));
} else {
set_deh_location (deh, EMPTY_DIR_SIZE_V1 - strlen ("."));
set_deh_location (deh + 1, get_deh_location (deh) - strlen (".."));
}
/* copy ".." and "." */
memcpy (body + get_deh_location (deh), ".", 1);
memcpy (body + get_deh_location (deh + 1), "..", 2);
}
void make_empty_dir_item_v1 (char * body, __u32 dirid, __u32 objid,
__u32 par_dirid, __u32 par_objid)
{
_empty_dir_item (KEY_FORMAT_1, body, dirid, objid, par_dirid, par_objid);
}
void make_empty_dir_item (char * body, __u32 dirid, __u32 objid,
__u32 par_dirid, __u32 par_objid)
{
_empty_dir_item (KEY_FORMAT_2, body, dirid, objid, par_dirid, par_objid);
}
/* for every item call common action and an action corresponding to
item type */
void for_every_item (struct buffer_head * bh, item_head_action_t action,
item_action_t * actions)
{
int i;
struct item_head * ih;
item_action_t iaction;
ih = B_N_PITEM_HEAD (bh, 0);
for (i = 0; i < get_blkh_nr_items (B_BLK_HEAD (bh)); i ++, ih ++) {
if (action)
action (ih);
iaction = actions[get_type (&ih->ih_key)];
if (iaction)
iaction (bh, ih);
}
}
#if __BYTE_ORDER == __LITTLE_ENDIAN
# define get_key_offset_v2(key) (__u64)((key->u.k2_offset_v2.k_offset))
# define set_key_offset_v2(key,val) (void)(key->u.k2_offset_v2.k_offset = (val))
# define get_key_type_v2(key) (__u16)((key->u.k2_offset_v2.k_type))
# define set_key_type_v2(key,val) (void)(key->u.k2_offset_v2.k_type = (val))
#elif __BYTE_ORDER == __BIG_ENDIAN
typedef union {
struct offset_v2 offset_v2;
__u64 linear;
} __attribute__ ((__packed__)) offset_v2_esafe_overlay;
static inline __u64 get_key_offset_v2 (const struct key *key)
{
offset_v2_esafe_overlay tmp =
*(offset_v2_esafe_overlay *) (&(key->u.k2_offset_v2));
tmp.linear = le64_to_cpu( tmp.linear );
return tmp.offset_v2.k_offset;
}
static inline __u32 get_key_type_v2 (const struct key *key)
{
offset_v2_esafe_overlay tmp =
*(offset_v2_esafe_overlay *) (&(key->u.k2_offset_v2));
tmp.linear = le64_to_cpu( tmp.linear );
return tmp.offset_v2.k_type;
}
static inline void set_key_offset_v2 (struct key *key, __u64 offset)
{
offset_v2_esafe_overlay *tmp =
(offset_v2_esafe_overlay *)(&(key->u.k2_offset_v2));
tmp->linear = le64_to_cpu(tmp->linear);
tmp->offset_v2.k_offset = offset;
tmp->linear = cpu_to_le64(tmp->linear);
}
static inline void set_key_type_v2 (struct key *key, __u32 type)
{
offset_v2_esafe_overlay *tmp =
(offset_v2_esafe_overlay *)(&(key->u.k2_offset_v2));
if (type > 15)
reiserfs_panic ("set_key_type_v2: type is too big %d", type);
tmp->linear = le64_to_cpu(tmp->linear);
tmp->offset_v2.k_type = type;
tmp->linear = cpu_to_le64(tmp->linear);
}
#else
# error "nuxi/pdp-endian archs are not supported"
#endif
static inline int is_key_format_1 (int type) {
return ( (type == 0 || type == 15) ? 1 : 0);
}
/* old keys (on i386) have k_offset_v2.k_type == 15 (direct and
indirect) or == 0 (dir items and stat data) */
/* */
int key_format (const struct key * key)
{
int type;
type = get_key_type_v2 (key);
if (is_key_format_1 (type))
return KEY_FORMAT_1;
return KEY_FORMAT_2;
}
loff_t get_offset (const struct key * key)
{
if (key_format (key) == KEY_FORMAT_1)
return get_key_offset_v1 (key);
return get_key_offset_v2 (key);
}
int uniqueness2type (__u32 uniqueness)
{
switch (uniqueness) {
case V1_SD_UNIQUENESS: return TYPE_STAT_DATA;
case V1_INDIRECT_UNIQUENESS: return TYPE_INDIRECT;
case V1_DIRECT_UNIQUENESS: return TYPE_DIRECT;
case V1_DIRENTRY_UNIQUENESS: return TYPE_DIRENTRY;
}
return TYPE_UNKNOWN;
}
__u32 type2uniqueness (int type)
{
switch (type) {
case TYPE_STAT_DATA: return V1_SD_UNIQUENESS;
case TYPE_INDIRECT: return V1_INDIRECT_UNIQUENESS;
case TYPE_DIRECT: return V1_DIRECT_UNIQUENESS;
case TYPE_DIRENTRY: return V1_DIRENTRY_UNIQUENESS;
}
return V1_UNKNOWN_UNIQUENESS;
}
int get_type (const struct key * key)
{
int type_v2 = get_key_type_v2 (key);
if (is_key_format_1 (type_v2))
return uniqueness2type (get_key_uniqueness (key));
return type_v2;
}
char * key_of_what (const struct key * key)
{
switch (get_type (key)) {
case TYPE_STAT_DATA: return "SD";
case TYPE_INDIRECT: return "IND";
case TYPE_DIRECT: return "DRCT";
case TYPE_DIRENTRY: return "DIR";
default: return "???";
}
}
int type_unknown (struct key * key)
{
int type = get_type (key);
switch (type) {
case TYPE_STAT_DATA:
case TYPE_INDIRECT:
case TYPE_DIRECT:
case TYPE_DIRENTRY:
return 0;
default:
break;
}
return 1;
}
// this sets key format as well as type of item key belongs to
//
void set_type (int format, struct key * key, int type)
{
if (format == KEY_FORMAT_1)
set_key_uniqueness (key, type2uniqueness (type));
else
set_key_type_v2 (key, type);
}
//
void set_offset (int format, struct key * key, loff_t offset)
{
if (format == KEY_FORMAT_1)
set_key_offset_v1 (key, offset);
else
set_key_offset_v2 (key, offset);
}
void set_type_and_offset (int format, struct key * key, loff_t offset, int type)
{
set_type (format, key, type);
set_offset (format, key, offset);
}
/* length of the directory entry in directory item. This define calculates
length of i-th directory entry using directory entry locations from dir
entry head. When it calculates length of 0-th directory entry, it uses
length of whole item in place of entry location of the non-existent
following entry in the calculation. See picture above.*/
// NOTE: this is not name length. This is length of whole entry
int entry_length (struct item_head * ih, struct reiserfs_de_head * deh, int pos_in_item)
{
if (pos_in_item)
return (get_deh_location (deh - 1) - get_deh_location (deh));
return (get_ih_item_len (ih) - get_deh_location (deh));
}
char * name_in_entry (struct reiserfs_de_head * deh, int pos_in_item)
{
return ((char *)(deh - pos_in_item) + get_deh_location(deh));
}
int name_in_entry_length (struct item_head * ih,
struct reiserfs_de_head * deh, int pos_in_item)
{
int len;
char * name;
len = entry_length (ih, deh, pos_in_item);
name = name_in_entry (deh, pos_in_item);
// name might be padded with 0s
while (!name [len - 1] && len > 0)
len --;
return len;
}
int name_length (char * name, int key_format)
{
if (key_format == KEY_FORMAT_2)
return ROUND_UP (strlen(name));
else if (key_format == KEY_FORMAT_1)
return strlen(name);
return -1;
}
/* key format is stored in 12 bits starting from 0-th of item_head's ih2_format*/
__u16 get_ih_key_format (const struct item_head * ih)
{
get_bit_field_XX (16, &ih->ih_format, 0, 12);
}
__u16 get_ih_flags (const struct item_head * ih)
{
get_bit_field_XX (16, &ih->ih_format, 12, 4);
}
void set_ih_key_format (struct item_head * ih, __u16 val)
{
set_bit_field_XX (16, &ih->ih_format, val, 0, 12);
}
void set_ih_flags (struct item_head * ih, __u16 val)
{
set_bit_field_XX (16, &ih->ih_format, val, 12, 4);
}
/* access to fields of stat data (both v1 and v2) */
void get_set_sd_field (int field, struct item_head * ih, void * sd,
void * value, int set)
{
if (get_ih_key_format (ih) == KEY_FORMAT_1) {
struct stat_data_v1 * sd_v1 = sd;
switch (field) {
case GET_SD_MODE:
if (set)
sd_v1->sd_mode = cpu_to_le16 (*(__u16 *)value);
else
*(__u16 *)value = le16_to_cpu (sd_v1->sd_mode);
break;
case GET_SD_SIZE:
/* value must point to 64 bit int */
if (set)
sd_v1->sd_size = cpu_to_le32 (*(__u64 *)value);
else
*(__u64 *)value = le32_to_cpu (sd_v1->sd_size);
break;
case GET_SD_BLOCKS:
if (set)
sd_v1->u.sd_blocks = cpu_to_le32 (*(__u32 *)value);
else
*(__u32 *)value = le32_to_cpu (sd_v1->u.sd_blocks);
break;
case GET_SD_NLINK:
/* value must point to 32 bit int */
if (set)
sd_v1->sd_nlink = cpu_to_le16 (*(__u32 *)value);
else
*(__u32 *)value = le16_to_cpu (sd_v1->sd_nlink);
break;
case GET_SD_FIRST_DIRECT_BYTE:
if (set)
sd_v1->sd_first_direct_byte = cpu_to_le32 (*(__u32 *)value);
else
*(__u32 *)value = le32_to_cpu (sd_v1->sd_first_direct_byte);
break;
default:
reiserfs_panic ("get_set_sd_field: unknown field of old stat data");
}
} else {
struct stat_data * sd_v2 = sd;
switch (field) {
case GET_SD_MODE:
if (set)
sd_v2->sd_mode = cpu_to_le16 (*(__u16 *)value);
else
*(__u16 *)value = le16_to_cpu (sd_v2->sd_mode);
break;
case GET_SD_SIZE:
if (set)
sd_v2->sd_size = cpu_to_le64 (*(__u64 *)value);
else
*(__u64 *)value = le64_to_cpu (sd_v2->sd_size);
break;
case GET_SD_BLOCKS:
if (set)
sd_v2->sd_blocks = cpu_to_le32 (*(__u32 *)value);
else
*(__u32 *)value = le32_to_cpu (sd_v2->sd_blocks);
break;
case GET_SD_NLINK:
if (set)
sd_v2->sd_nlink = cpu_to_le32 (*(__u32 *)value);
else
*(__u32 *)value = le32_to_cpu (sd_v2->sd_nlink);
break;
case GET_SD_FIRST_DIRECT_BYTE:
default:
reiserfs_panic ("get_set_sd_field: unknown field of new stat data");
}
}
}
int comp_ids (const void * p1, const void * p2)
{
__u32 id1 = le32_to_cpu(*(__u32 *)p1) ;
__u32 id2 = le32_to_cpu(*(__u32 *)p2) ;
if (id1 < id2)
return -1;
if (id1 > id2)
return 1 ;
return 0 ;
}
/* functions to manipulate with super block's objectid map */
int is_objectid_used (reiserfs_filsys_t * fs, __u32 objectid)
{
__u32 * objectid_map;
__u32 count = get_sb_oid_cursize(fs->fs_ondisk_sb);
int ret;
__u32 pos;
__u32 le_id = cpu_to_le32(objectid);
objectid_map = (__u32 *)((char *)fs->fs_ondisk_sb + reiserfs_super_block_size (fs->fs_ondisk_sb));
ret = reiserfs_bin_search(&le_id, objectid_map, count, sizeof(__u32), &pos, comp_ids);
/* if the position returned is odd, the oid is in use */
if (ret == POSITION_NOT_FOUND)
return (pos & 1) ;
/* if the position returned is even, the oid is in use */
return !(pos & 1) ;
}
void mark_objectid_used (reiserfs_filsys_t * fs, __u32 objectid)
{
int i;
__u32 * objectid_map;
int cursize;
if (is_objectid_used (fs, objectid)) {
return;
}
objectid_map = (__u32 *)((char *)fs->fs_ondisk_sb + reiserfs_super_block_size (fs->fs_ondisk_sb));
cursize = get_sb_oid_cursize (fs->fs_ondisk_sb);
for (i = 0; i < cursize; i += 2) {
if (objectid >= le32_to_cpu (objectid_map [i]) &&
objectid < le32_to_cpu (objectid_map [i + 1]))
/* it is used */
return;
if (objectid + 1 == le32_to_cpu (objectid_map[i])) {
/* size of objectid map does not change */
objectid_map[i] = cpu_to_le32 (objectid);
return;
}
if (objectid == le32_to_cpu (objectid_map[i + 1])) {
/* size of objectid map is decreased */
objectid_map [i + 1] = cpu_to_le32 (le32_to_cpu (objectid_map [i + 1]) + 1);
if (i + 2 < cursize) {
if (objectid_map[i + 1] == objectid_map[i + 2]) {
memmove (objectid_map + i + 1, objectid_map + i + 1 + 2,
(cursize - (i + 2 + 2 - 1)) * sizeof (__u32));
set_sb_oid_cursize (fs->fs_ondisk_sb, cursize - 2);
}
}
return;
}
if (objectid < le32_to_cpu (objectid_map[i])) {
/* size of objectid map must be increased */
if (cursize == get_sb_oid_maxsize (fs->fs_ondisk_sb)) {
/* here all objectids between objectid and objectid_map[i] get
used */
objectid_map[i] = cpu_to_le32 (objectid);
return;
} else {
memmove (objectid_map + i + 2, objectid_map + i, (cursize - i) * sizeof (__u32));
set_sb_oid_cursize (fs->fs_ondisk_sb, cursize + 2);
}
objectid_map[i] = cpu_to_le32 (objectid);
objectid_map[i+1] = cpu_to_le32 (objectid + 1);
return;
}
}
/* append to current objectid map, if we have space */
if (i < get_sb_oid_maxsize (fs->fs_ondisk_sb)) {
objectid_map[i] = cpu_to_le32 (objectid);
objectid_map[i + 1] = cpu_to_le32 (objectid + 1);
set_sb_oid_cursize (fs->fs_ondisk_sb, cursize + 2);
} else if (i == get_sb_oid_maxsize (fs->fs_ondisk_sb)) {
objectid_map[i - 1] = cpu_to_le32 (objectid + 1);
} else
die ("mark_objectid_as_used: objectid map corrupted");
return;
}
int is_blocksize_correct (int blocksize)
{
return ((blocksize % 1024) ? 0 : 1);
}
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