/* fills the structure with various parameters of directory entry,
including key of the pointed object */
static void get_entry_attributes (struct reiserfs_dir_entry * de, int entry_num)
{
#ifdef REISERFS_CHECK
if (I_ENTRY_COUNT (de->de_ih) < entry_num)
reiserfs_panic (0, "yr-7006: get_entry_attributes: no such entry (%d-th) in the item (%d)",
entry_num, I_ENTRY_COUNT (de->de_ih));
if (de->de_deh != B_I_DEH (de->de_bh, de->de_ih) + entry_num)
reiserfs_panic (0, "yr-7008: get_entry_attributes: dir entry header not found");
#endif /* REISERFS_CHECK */
/* few fields are set already (de_bh, de_item_num, de_deh) */
de->de_entrylen = I_DEH_N_ENTRY_LENGTH (de->de_ih, de->de_deh, entry_num);
de->de_namelen = de->de_entrylen - (de_with_sd (de->de_deh) ? SD_SIZE : 0);
de->de_name = B_I_PITEM (de->de_bh, de->de_ih) + de->de_deh->deh_location;
#ifdef REISERFS_ALIGNED
if ( de->de_name[ de->de_namelen-1 ] == '\0' )
de->de_namelen = strlen(de->de_name);
#endif
/* key of object pointed by entry */
de->de_dir_id = de->de_deh->deh_dir_id;
de->de_objectid = de->de_deh->deh_objectid;
/* key of the entry */
memcpy (&(de->de_entry_key.k_dir_id), &(de->de_ih->ih_key), SHORT_KEY_SIZE);
de->de_entry_key.k_offset = de->de_deh->deh_offset;
de->de_entry_key.k_uniqueness = DIRENTRY_UNIQUENESS;
}
// directory item contains array of entry headers. This performs
// binary search through that array
static int bin_search_in_dir_item(struct reiserfs_dir_entry *de, loff_t off)
{
struct item_head *ih = de->de_ih;
struct reiserfs_de_head *deh = de->de_deh;
int rbound, lbound, j;
lbound = 0;
rbound = I_ENTRY_COUNT(ih) - 1;
for (j = (rbound + lbound) / 2; lbound <= rbound;
j = (rbound + lbound) / 2) {
if (off < deh_offset(deh + j)) {
rbound = j - 1;
continue;
}
if (off > deh_offset(deh + j)) {
lbound = j + 1;
continue;
}
// this is not name found, but matched third key component
de->de_entry_num = j;
return NAME_FOUND;
}
de->de_entry_num = lbound;
return NAME_NOT_FOUND;
}
/* after this function de_entry_num is set correctly only if name
found or there was no entries with given hash value */
static int linear_search_in_dir_item (struct key * key, struct reiserfs_dir_entry * de, const char * name, int namelen)
{
int retval;
int i;
i = de->de_entry_num;
if (i == I_ENTRY_COUNT (de->de_ih) ||
GET_HASH_VALUE (de->de_deh[i].deh_offset) != GET_HASH_VALUE (key->k_offset)) {
i --;
}
#ifdef REISERFS_CHECK
if (de->de_deh != B_I_DEH (de->de_bh, de->de_ih))
reiserfs_panic (0, "vs-7010: linear_search_in_dir_item: array of entry headers not found");
#endif /* REISERFS_CHECK */
de->de_deh += i;
for (; i >= 0; i --, de->de_deh --) {
if (GET_HASH_VALUE (de->de_deh->deh_offset) != GET_HASH_VALUE (key->k_offset)) {
return POSITION_NOT_FOUND;
}
/* mark, that this generation number is used */
if (de->de_gen_number_bit_string)
set_bit (GET_GENERATION_NUMBER (de->de_deh->deh_offset), de->de_gen_number_bit_string);
/* de_bh, de_item_num, de_ih, de_deh are already set. Set others fields */
get_entry_attributes (de, i);
if ((retval = try_name (de, name, namelen)) != POSITION_NOT_FOUND) {
de->de_entry_num = i;
return retval;
}
}
if (GET_GENERATION_NUMBER (de->de_ih->ih_key.k_offset) == 0)
return POSITION_NOT_FOUND;
#ifdef REISERFS_CHECK
if (de->de_ih->ih_key.k_offset <= DOT_DOT_OFFSET || de->de_item_num != 0)
reiserfs_panic (0, "vs-7015: linear_search_in_dir_item: item must be 0-th item in block (%d)", de->de_item_num);
#endif /* REISERFS_CHECK */
return GOTO_PREVIOUS_ITEM;
}
int bin_search_in_dir_item (struct item_head * ih, struct reiserfs_de_head * deh, struct key * key, int * pos_in_item)
{
int rbound, lbound, j;
lbound = 0;
rbound = I_ENTRY_COUNT (ih) - 1;
for (j = (rbound + lbound) / 2; lbound <= rbound; j = (rbound + lbound) / 2) {
if (key->k_offset < deh[j].deh_offset) {
rbound = j - 1;
continue;
}
if (key->k_offset > deh[j].deh_offset) {
lbound = j + 1;
continue;
}
/* key found */
*pos_in_item = j;
return POSITION_FOUND;
}
*pos_in_item = lbound;
return POSITION_NOT_FOUND;
}
static int reiserfs_readdir (struct file * filp, void * dirent, filldir_t filldir)
{
struct inode *inode = filp->f_dentry->d_inode;
struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
INITIALIZE_PATH (path_to_entry);
struct buffer_head * bh;
int item_num, entry_num;
const struct key * rkey;
struct item_head * ih, tmp_ih;
int search_res;
char * local_buf;
loff_t next_pos;
char small_buf[32] ; /* avoid kmalloc if we can */
struct reiserfs_dir_entry de;
reiserfs_check_lock_depth("readdir") ;
/* form key for search the next directory entry using f_pos field of
file structure */
make_cpu_key (&pos_key, inode, (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET,
TYPE_DIRENTRY, 3);
next_pos = cpu_key_k_offset (&pos_key);
/* reiserfs_warning ("reiserfs_readdir 1: f_pos = %Ld\n", filp->f_pos);*/
while (1) {
research:
/* search the directory item, containing entry with specified key */
search_res = search_by_entry_key (inode->i_sb, &pos_key, &path_to_entry, &de);
if (search_res == IO_ERROR) {
// FIXME: we could just skip part of directory which could
// not be read
return -EIO;
}
entry_num = de.de_entry_num;
bh = de.de_bh;
item_num = de.de_item_num;
ih = de.de_ih;
store_ih (&tmp_ih, ih);
/* we must have found item, that is item of this directory, */
RFALSE( COMP_SHORT_KEYS (&(ih->ih_key), &pos_key),
"vs-9000: found item %h does not match to dir we readdir %K",
ih, &pos_key);
RFALSE( item_num > B_NR_ITEMS (bh) - 1,
"vs-9005 item_num == %d, item amount == %d",
item_num, B_NR_ITEMS (bh));
/* and entry must be not more than number of entries in the item */
RFALSE( I_ENTRY_COUNT (ih) < entry_num,
"vs-9010: entry number is too big %d (%d)",
entry_num, I_ENTRY_COUNT (ih));
if (search_res == POSITION_FOUND || entry_num < I_ENTRY_COUNT (ih)) {
/* go through all entries in the directory item beginning from the entry, that has been found */
struct reiserfs_de_head * deh = B_I_DEH (bh, ih) + entry_num;
for (; entry_num < I_ENTRY_COUNT (ih); entry_num ++, deh ++) {
int d_reclen;
char * d_name;
off_t d_off;
ino_t d_ino;
if (!de_visible (deh))
/* it is hidden entry */
continue;
d_reclen = entry_length (bh, ih, entry_num);
d_name = B_I_DEH_ENTRY_FILE_NAME (bh, ih, deh);
if (!d_name[d_reclen - 1])
d_reclen = strlen (d_name);
if (d_reclen > REISERFS_MAX_NAME_LEN(inode->i_sb->s_blocksize)){
/* too big to send back to VFS */
continue ;
}
d_off = deh_offset (deh);
filp->f_pos = d_off ;
d_ino = deh_objectid (deh);
if (d_reclen <= 32) {
local_buf = small_buf ;
} else {
local_buf = reiserfs_kmalloc(d_reclen, GFP_NOFS, inode->i_sb) ;
if (!local_buf) {
pathrelse (&path_to_entry);
return -ENOMEM ;
}
if (item_moved (&tmp_ih, &path_to_entry)) {
reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
goto research;
}
}
// Note, that we copy name to user space via temporary
// buffer (local_buf) because filldir will block if
// user space buffer is swapped out. At that time
// entry can move to somewhere else
memcpy (local_buf, d_name, d_reclen);
if (filldir (dirent, local_buf, d_reclen, d_off, d_ino,
DT_UNKNOWN) < 0) {
if (local_buf != small_buf) {
reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
}
goto end;
}
if (local_buf != small_buf) {
reiserfs_kfree(local_buf, d_reclen, inode->i_sb) ;
}
// next entry should be looked for with such offset
next_pos = deh_offset (deh) + 1;
if (item_moved (&tmp_ih, &path_to_entry)) {
goto research;
}
} /* for */
}
if (item_num != B_NR_ITEMS (bh) - 1)
// end of directory has been reached
goto end;
/* item we went through is last item of node. Using right
delimiting key check is it directory end */
rkey = get_rkey (&path_to_entry, inode->i_sb);
if (! comp_le_keys (rkey, &MIN_KEY)) {
/* set pos_key to key, that is the smallest and greater
that key of the last entry in the item */
set_cpu_key_k_offset (&pos_key, next_pos);
continue;
}
if ( COMP_SHORT_KEYS (rkey, &pos_key)) {
// end of directory has been reached
goto end;
}
/* directory continues in the right neighboring block */
set_cpu_key_k_offset (&pos_key, le_key_k_offset (KEY_FORMAT_3_5, rkey));
} /* while */
end:
// FIXME: ext2_readdir does not reset f_pos
filp->f_pos = next_pos;
pathrelse (&path_to_entry);
reiserfs_check_path(&path_to_entry) ;
UPDATE_ATIME(inode) ;
return 0;
}
static int linear_search_in_dir_item(struct cpu_key *key,
struct reiserfs_dir_entry *de,
const char *name, int namelen)
{
struct reiserfs_de_head *deh = de->de_deh;
int retval;
int i;
i = de->de_entry_num;
if (i == I_ENTRY_COUNT(de->de_ih) ||
GET_HASH_VALUE(deh_offset(deh + i)) !=
GET_HASH_VALUE(cpu_key_k_offset(key))) {
i--;
}
RFALSE(de->de_deh != B_I_DEH(de->de_bh, de->de_ih),
"vs-7010: array of entry headers not found");
deh += i;
for (; i >= 0; i--, deh--) {
if (GET_HASH_VALUE(deh_offset(deh)) !=
GET_HASH_VALUE(cpu_key_k_offset(key))) {
// hash value does not match, no need to check whole name
return NAME_NOT_FOUND;
}
/* mark, that this generation number is used */
if (de->de_gen_number_bit_string)
set_bit(GET_GENERATION_NUMBER(deh_offset(deh)),
de->de_gen_number_bit_string);
// calculate pointer to name and namelen
de->de_entry_num = i;
set_de_name_and_namelen(de);
if ((retval =
reiserfs_match(de, name, namelen)) != NAME_NOT_FOUND) {
// de's de_name, de_namelen, de_recordlen are set. Fill the rest:
// key of pointed object
set_de_object_key(de);
store_de_entry_key(de);
// retval can be NAME_FOUND or NAME_FOUND_INVISIBLE
return retval;
}
}
if (GET_GENERATION_NUMBER(le_ih_k_offset(de->de_ih)) == 0)
/* we have reached left most entry in the node. In common we
have to go to the left neighbor, but if generation counter
is 0 already, we know for sure, that there is no name with
the same hash value */
// FIXME: this work correctly only because hash value can not
// be 0. Btw, in case of Yura's hash it is probably possible,
// so, this is a bug
return NAME_NOT_FOUND;
RFALSE(de->de_item_num,
"vs-7015: two diritems of the same directory in one node?");
return GOTO_PREVIOUS_ITEM;
}
/*
* de's de_bh, de_ih, de_deh, de_item_num, de_entry_num are set already
* Used when hash collisions exist
*/
static int
linear_search_in_dir_item(struct cpu_key *key, struct reiserfs_dir_entry *de,
const char *name, int namelen)
{
int i;
int retval;
struct reiserfs_de_head * deh = de->de_deh;
i = de->de_entry_num;
if (i == I_ENTRY_COUNT(de->de_ih) ||
GET_HASH_VALUE(deh_offset(deh + i)) !=
GET_HASH_VALUE(cpu_key_k_offset(key))) {
i--;
}
/*RFALSE( de->de_deh != B_I_DEH (de->de_bh, de->de_ih),
"vs-7010: array of entry headers not found");*/
deh += i;
for (; i >= 0; i--, deh--) {
if (GET_HASH_VALUE(deh_offset(deh)) !=
GET_HASH_VALUE(cpu_key_k_offset(key))) {
/*
* Hash value does not match, no need to check
* whole name
*/
reiserfs_log(LOG_DEBUG, "name `%s' not found\n", name);
return (NAME_NOT_FOUND);
}
/* Mark that this generation number is used */
if (de->de_gen_number_bit_string)
set_bit(GET_GENERATION_NUMBER(deh_offset(deh)),
(unsigned long *)de->de_gen_number_bit_string);
/* Calculate pointer to name and namelen */
de->de_entry_num = i;
set_de_name_and_namelen(de);
if ((retval = reiserfs_match(de, name, namelen)) !=
NAME_NOT_FOUND) {
/*
* de's de_name, de_namelen, de_recordlen are set.
* Fill the rest:
*/
/* key of pointed object */
set_de_object_key(de);
store_de_entry_key(de);
/* retval can be NAME_FOUND or NAME_FOUND_INVISIBLE */
reiserfs_log(LOG_DEBUG,
"reiserfs_match answered `%d'\n",
retval);
return (retval);
}
}
if (GET_GENERATION_NUMBER(le_ih_k_offset(de->de_ih)) == 0)
/*
* We have reached left most entry in the node. In common
* we have to go to the left neighbor, but if generation
* counter is 0 already, we know for sure, that there is
* no name with the same hash value
*/
/* FIXME: this work correctly only because hash value can
* not be 0. Btw, in case of Yura's hash it is probably
* possible, so, this is a bug
*/
return (NAME_NOT_FOUND);
/*RFALSE(de->de_item_num,
"vs-7015: two diritems of the same directory in one node?");*/
return (GOTO_PREVIOUS_ITEM);
}
int
reiserfs_readdir(struct vop_readdir_args /* {
struct vnode *a_vp;
struct uio *a_uio;
struct ucred *a_cred;
int *a_eofflag;
int *a_ncookies;
u_long **a_cookies;
} */*ap)
{
int error = 0;
struct dirent dstdp;
struct uio *uio = ap->a_uio;
off_t next_pos;
struct buf *bp;
struct item_head *ih;
struct cpu_key pos_key;
const struct key *rkey;
struct reiserfs_node *ip;
struct reiserfs_dir_entry de;
INITIALIZE_PATH(path_to_entry);
int entry_num, item_num, search_res;
/* The NFS part */
int ncookies = 0;
u_long *cookies = NULL;
/*
* Form key for search the next directory entry using f_pos field of
* file structure
*/
ip = VTOI(ap->a_vp);
make_cpu_key(&pos_key,
ip, uio->uio_offset ? uio->uio_offset : DOT_OFFSET,
TYPE_DIRENTRY, 3);
next_pos = cpu_key_k_offset(&pos_key);
reiserfs_log(LOG_DEBUG, "listing entries for "
"(objectid=%d, dirid=%d)\n",
pos_key.on_disk_key.k_objectid, pos_key.on_disk_key.k_dir_id);
reiserfs_log(LOG_DEBUG, "uio_offset = %jd, uio_resid = %d\n",
(intmax_t)uio->uio_offset, uio->uio_resid);
if (ap->a_ncookies && ap->a_cookies) {
cookies = (u_long *)malloc(
uio->uio_resid / 16 * sizeof(u_long),
M_REISERFSCOOKIES, M_WAITOK);
}
while (1) {
//research:
/*
* Search the directory item, containing entry with
* specified key
*/
reiserfs_log(LOG_DEBUG, "search directory to read\n");
search_res = search_by_entry_key(ip->i_reiserfs, &pos_key,
&path_to_entry, &de);
if (search_res == IO_ERROR) {
error = EIO;
goto out;
}
entry_num = de.de_entry_num;
item_num = de.de_item_num;
bp = de.de_bp;
ih = de.de_ih;
if (search_res == POSITION_FOUND ||
entry_num < I_ENTRY_COUNT(ih)) {
/*
* Go through all entries in the directory item
* beginning from the entry, that has been found.
*/
struct reiserfs_de_head *deh = B_I_DEH(bp, ih) +
entry_num;
if (ap->a_ncookies == NULL) {
cookies = NULL;
} else {
//ncookies =
}
reiserfs_log(LOG_DEBUG,
"walking through directory entries\n");
for (; entry_num < I_ENTRY_COUNT(ih);
entry_num++, deh++) {
int d_namlen;
char *d_name;
off_t d_off;
ino_t d_ino;
if (!de_visible(deh)) {
/* It is hidden entry */
continue;
}
d_namlen = entry_length(bp, ih, entry_num);
d_name = B_I_DEH_ENTRY_FILE_NAME(bp, ih, deh);
if (!d_name[d_namlen - 1])
d_namlen = strlen(d_name);
reiserfs_log(LOG_DEBUG, " - `%s' (len=%d)\n",
d_name, d_namlen);
if (d_namlen > REISERFS_MAX_NAME(
ip->i_reiserfs->s_blocksize)) {
/* Too big to send back to VFS */
continue;
}
#if 0
/* Ignore the .reiserfs_priv entry */
if (reiserfs_xattrs(ip->i_reiserfs) &&
!old_format_only(ip->i_reiserfs) &&
filp->f_dentry == ip->i_reiserfs->s_root &&
REISERFS_SB(ip->i_reiserfs)->priv_root &&
REISERFS_SB(ip->i_reiserfs)->priv_root->d_inode &&
deh_objectid(deh) ==
le32toh(INODE_PKEY(REISERFS_SB(
ip->i_reiserfs)->priv_root->d_inode)->k_objectid)) {
continue;
}
#endif
d_off = deh_offset(deh);
d_ino = deh_objectid(deh);
uio->uio_offset = d_off;
/* Copy to user land */
dstdp.d_fileno = d_ino;
dstdp.d_type = DT_UNKNOWN;
dstdp.d_namlen = d_namlen;
dstdp.d_reclen = GENERIC_DIRSIZ(&dstdp);
bcopy(d_name, dstdp.d_name, dstdp.d_namlen);
bzero(dstdp.d_name + dstdp.d_namlen,
dstdp.d_reclen -
offsetof(struct dirent, d_name) -
dstdp.d_namlen);
if (d_namlen > 0) {
if (dstdp.d_reclen <= uio->uio_resid) {
reiserfs_log(LOG_DEBUG, " copying to user land\n");
error = uiomove(&dstdp,
dstdp.d_reclen, uio);
if (error)
goto end;
if (cookies != NULL) {
cookies[ncookies] =
d_off;
ncookies++;
}
} else
break;
} else {
error = EIO;
break;
}
next_pos = deh_offset(deh) + 1;
}
reiserfs_log(LOG_DEBUG, "...done\n");
}
reiserfs_log(LOG_DEBUG, "checking item num (%d == %d ?)\n",
item_num, B_NR_ITEMS(bp) - 1);
if (item_num != B_NR_ITEMS(bp) - 1) {
/* End of directory has been reached */
reiserfs_log(LOG_DEBUG, "end reached\n");
if (ap->a_eofflag)
*ap->a_eofflag = 1;
goto end;
}
/*
* Item we went through is last item of node. Using right
* delimiting key check is it directory end
*/
reiserfs_log(LOG_DEBUG, "get right key\n");
rkey = get_rkey(&path_to_entry, ip->i_reiserfs);
reiserfs_log(LOG_DEBUG, "right key = (objectid=%d, dirid=%d)\n",
rkey->k_objectid, rkey->k_dir_id);
reiserfs_log(LOG_DEBUG, "compare it to MIN_KEY\n");
reiserfs_log(LOG_DEBUG, "MIN KEY = (objectid=%d, dirid=%d)\n",
MIN_KEY.k_objectid, MIN_KEY.k_dir_id);
if (comp_le_keys(rkey, &MIN_KEY) == 0) {
/* Set pos_key to key, that is the smallest and greater
* that key of the last entry in the item */
reiserfs_log(LOG_DEBUG, "continuing on the right\n");
set_cpu_key_k_offset(&pos_key, next_pos);
continue;
}
reiserfs_log(LOG_DEBUG, "compare it to pos_key\n");
reiserfs_log(LOG_DEBUG, "pos key = (objectid=%d, dirid=%d)\n",
pos_key.on_disk_key.k_objectid,
pos_key.on_disk_key.k_dir_id);
if (COMP_SHORT_KEYS(rkey, &pos_key)) {
/* End of directory has been reached */
reiserfs_log(LOG_DEBUG, "end reached (right)\n");
if (ap->a_eofflag)
*ap->a_eofflag = 1;
goto end;
}
/* Directory continues in the right neighboring block */
reiserfs_log(LOG_DEBUG, "continuing with a new offset\n");
set_cpu_key_k_offset(&pos_key,
le_key_k_offset(KEY_FORMAT_3_5, rkey));
reiserfs_log(LOG_DEBUG,
"new pos key = (objectid=%d, dirid=%d)\n",
pos_key.on_disk_key.k_objectid,
pos_key.on_disk_key.k_dir_id);
}
end:
uio->uio_offset = next_pos;
pathrelse(&path_to_entry);
reiserfs_check_path(&path_to_entry);
out:
if (error && cookies != NULL) {
free(cookies, M_REISERFSCOOKIES);
} else if (ap->a_ncookies != NULL && ap->a_cookies != NULL) {
*ap->a_ncookies = ncookies;
*ap->a_cookies = cookies;
}
return (error);
}
int reiserfs_readdir_dentry(struct dentry *dentry, void *dirent,
filldir_t filldir, loff_t *pos)
{
struct inode *inode = dentry->d_inode;
struct cpu_key pos_key;
INITIALIZE_PATH(path_to_entry);
struct buffer_head *bh;
int item_num, entry_num;
const struct reiserfs_key *rkey;
struct item_head *ih, tmp_ih;
int search_res;
char *local_buf;
loff_t next_pos;
char small_buf[32];
struct reiserfs_dir_entry de;
int ret = 0;
reiserfs_write_lock(inode->i_sb);
reiserfs_check_lock_depth(inode->i_sb, "readdir");
make_cpu_key(&pos_key, inode, *pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
next_pos = cpu_key_k_offset(&pos_key);
path_to_entry.reada = PATH_READA;
while (1) {
research:
search_res =
search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
&de);
if (search_res == IO_ERROR) {
ret = -EIO;
goto out;
}
entry_num = de.de_entry_num;
bh = de.de_bh;
item_num = de.de_item_num;
ih = de.de_ih;
store_ih(&tmp_ih, ih);
RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
"vs-9000: found item %h does not match to dir we readdir %K",
ih, &pos_key);
RFALSE(item_num > B_NR_ITEMS(bh) - 1,
"vs-9005 item_num == %d, item amount == %d",
item_num, B_NR_ITEMS(bh));
RFALSE(I_ENTRY_COUNT(ih) < entry_num,
"vs-9010: entry number is too big %d (%d)",
entry_num, I_ENTRY_COUNT(ih));
if (search_res == POSITION_FOUND
|| entry_num < I_ENTRY_COUNT(ih)) {
struct reiserfs_de_head *deh =
B_I_DEH(bh, ih) + entry_num;
for (; entry_num < I_ENTRY_COUNT(ih);
entry_num++, deh++) {
int d_reclen;
char *d_name;
off_t d_off;
ino_t d_ino;
if (!de_visible(deh))
continue;
d_reclen = entry_length(bh, ih, entry_num);
d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
if (d_reclen <= 0 ||
d_name + d_reclen > bh->b_data + bh->b_size) {
pathrelse(&path_to_entry);
ret = -EIO;
goto out;
}
if (!d_name[d_reclen - 1])
d_reclen = strlen(d_name);
if (d_reclen >
REISERFS_MAX_NAME(inode->i_sb->
s_blocksize)) {
continue;
}
if (is_privroot_deh(dentry, deh))
continue;
d_off = deh_offset(deh);
*pos = d_off;
d_ino = deh_objectid(deh);
if (d_reclen <= 32) {
local_buf = small_buf;
} else {
local_buf = kmalloc(d_reclen,
GFP_NOFS);
if (!local_buf) {
pathrelse(&path_to_entry);
ret = -ENOMEM;
goto out;
}
if (item_moved(&tmp_ih, &path_to_entry)) {
kfree(local_buf);
goto research;
}
}
memcpy(local_buf, d_name, d_reclen);
reiserfs_write_unlock(inode->i_sb);
if (filldir
(dirent, local_buf, d_reclen, d_off, d_ino,
DT_UNKNOWN) < 0) {
reiserfs_write_lock(inode->i_sb);
if (local_buf != small_buf) {
kfree(local_buf);
}
goto end;
}
reiserfs_write_lock(inode->i_sb);
if (local_buf != small_buf) {
kfree(local_buf);
}
next_pos = deh_offset(deh) + 1;
if (item_moved(&tmp_ih, &path_to_entry)) {
goto research;
}
}
}
if (item_num != B_NR_ITEMS(bh) - 1)
goto end;
rkey = get_rkey(&path_to_entry, inode->i_sb);
if (!comp_le_keys(rkey, &MIN_KEY)) {
set_cpu_key_k_offset(&pos_key, next_pos);
continue;
}
if (COMP_SHORT_KEYS(rkey, &pos_key)) {
goto end;
}
set_cpu_key_k_offset(&pos_key,
le_key_k_offset(KEY_FORMAT_3_5, rkey));
}
end:
*pos = next_pos;
pathrelse(&path_to_entry);
reiserfs_check_path(&path_to_entry);
out:
reiserfs_write_unlock(inode->i_sb);
return ret;
}
int reiserfs_readdir_dentry(struct dentry *dentry, void *dirent,
filldir_t filldir, loff_t *pos)
{
struct inode *inode = dentry->d_inode;
struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
INITIALIZE_PATH(path_to_entry);
struct buffer_head *bh;
int item_num, entry_num;
const struct reiserfs_key *rkey;
struct item_head *ih, tmp_ih;
int search_res;
char *local_buf;
loff_t next_pos;
char small_buf[32]; /* avoid kmalloc if we can */
struct reiserfs_dir_entry de;
int ret = 0;
reiserfs_write_lock(inode->i_sb);
reiserfs_check_lock_depth(inode->i_sb, "readdir");
/* form key for search the next directory entry using f_pos field of
file structure */
make_cpu_key(&pos_key, inode, *pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
next_pos = cpu_key_k_offset(&pos_key);
path_to_entry.reada = PATH_READA;
while (1) {
research:
/* search the directory item, containing entry with specified key */
search_res =
search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
&de);
if (search_res == IO_ERROR) {
// FIXME: we could just skip part of directory which could
// not be read
ret = -EIO;
goto out;
}
entry_num = de.de_entry_num;
bh = de.de_bh;
item_num = de.de_item_num;
ih = de.de_ih;
store_ih(&tmp_ih, ih);
/* we must have found item, that is item of this directory, */
RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
"vs-9000: found item %h does not match to dir we readdir %K",
ih, &pos_key);
RFALSE(item_num > B_NR_ITEMS(bh) - 1,
"vs-9005 item_num == %d, item amount == %d",
item_num, B_NR_ITEMS(bh));
/* and entry must be not more than number of entries in the item */
RFALSE(I_ENTRY_COUNT(ih) < entry_num,
"vs-9010: entry number is too big %d (%d)",
entry_num, I_ENTRY_COUNT(ih));
if (search_res == POSITION_FOUND
|| entry_num < I_ENTRY_COUNT(ih)) {
/* go through all entries in the directory item beginning from the entry, that has been found */
struct reiserfs_de_head *deh =
B_I_DEH(bh, ih) + entry_num;
for (; entry_num < I_ENTRY_COUNT(ih);
entry_num++, deh++) {
int d_reclen;
char *d_name;
off_t d_off;
ino_t d_ino;
loff_t cur_pos = deh_offset(deh);
if (!de_visible(deh))
/* it is hidden entry */
continue;
d_reclen = entry_length(bh, ih, entry_num);
d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
if (d_reclen <= 0 ||
d_name + d_reclen > bh->b_data + bh->b_size) {
/* There is corrupted data in entry,
* We'd better stop here */
pathrelse(&path_to_entry);
ret = -EIO;
goto out;
}
if (!d_name[d_reclen - 1])
d_reclen = strlen(d_name);
if (d_reclen >
REISERFS_MAX_NAME(inode->i_sb->
s_blocksize)) {
/* too big to send back to VFS */
continue;
}
/* Ignore the .reiserfs_priv entry */
if (is_privroot_deh(dentry, deh))
continue;
d_off = deh_offset(deh);
*pos = d_off;
d_ino = deh_objectid(deh);
if (d_reclen <= 32) {
local_buf = small_buf;
} else {
local_buf = kmalloc(d_reclen,
GFP_NOFS);
if (!local_buf) {
pathrelse(&path_to_entry);
ret = -ENOMEM;
goto out;
}
if (item_moved(&tmp_ih, &path_to_entry)) {
kfree(local_buf);
goto research;
}
}
// Note, that we copy name to user space via temporary
// buffer (local_buf) because filldir will block if
// user space buffer is swapped out. At that time
// entry can move to somewhere else
memcpy(local_buf, d_name, d_reclen);
/*
* Since filldir might sleep, we can release
* the write lock here for other waiters
*/
reiserfs_write_unlock(inode->i_sb);
if (filldir
(dirent, local_buf, d_reclen, d_off, d_ino,
DT_UNKNOWN) < 0) {
reiserfs_write_lock(inode->i_sb);
if (local_buf != small_buf) {
kfree(local_buf);
}
goto end;
}
reiserfs_write_lock(inode->i_sb);
if (local_buf != small_buf) {
kfree(local_buf);
}
/* deh_offset(deh) may be invalid now. */
next_pos = cur_pos + 1;
if (item_moved(&tmp_ih, &path_to_entry)) {
set_cpu_key_k_offset(&pos_key,
next_pos);
goto research;
}
} /* for */
}
if (item_num != B_NR_ITEMS(bh) - 1)
// end of directory has been reached
goto end;
/* item we went through is last item of node. Using right
delimiting key check is it directory end */
rkey = get_rkey(&path_to_entry, inode->i_sb);
if (!comp_le_keys(rkey, &MIN_KEY)) {
/* set pos_key to key, that is the smallest and greater
that key of the last entry in the item */
set_cpu_key_k_offset(&pos_key, next_pos);
continue;
}
if (COMP_SHORT_KEYS(rkey, &pos_key)) {
// end of directory has been reached
goto end;
}
/* directory continues in the right neighboring block */
set_cpu_key_k_offset(&pos_key,
le_key_k_offset(KEY_FORMAT_3_5, rkey));
} /* while */
end:
*pos = next_pos;
pathrelse(&path_to_entry);
reiserfs_check_path(&path_to_entry);
out:
reiserfs_write_unlock(inode->i_sb);
return ret;
}
