/*
* k1 is pointer to on-disk structure which is stored in little-endian
* form. k2 is pointer to cpu variable. Compare keys using all 4 key
* fields.
* Returns: -1 if key1 < key2, 0 if key1 = key2 or 1 if key1 > key2
*/
/*inline*/ int
comp_keys(const struct key *le_key, const struct cpu_key *cpu_key)
{
int retval;
retval = comp_short_keys(le_key, cpu_key);
if (retval)
return retval;
if (le_key_k_offset(le_key_version(le_key), le_key) <
cpu_key_k_offset(cpu_key))
return (-1);
if (le_key_k_offset(le_key_version(le_key), le_key) >
cpu_key_k_offset(cpu_key))
return (1);
if (cpu_key->key_length == 3)
return (0);
/* This part is needed only when tail conversion is in progress */
if (le_key_k_type(le_key_version(le_key), le_key) <
cpu_key_k_type(cpu_key))
return (-1);
if (le_key_k_type(le_key_version(le_key), le_key) >
cpu_key_k_type(cpu_key))
return (1);
return (0);
}
/* k1 is pointer to on-disk structure which is stored in little-endian
form. k2 is pointer to cpu variable.
Compare keys using all 4 key fields.
Returns: -1 if key1 < key2 0
if key1 = key2 1 if key1 > key2 */
static inline int comp_keys(const struct reiserfs_key *le_key,
const struct cpu_key *cpu_key)
{
int retval;
retval = comp_short_keys(le_key, cpu_key);
if (retval)
return retval;
if (le_key_k_offset(le_key_version(le_key), le_key) <
cpu_key_k_offset(cpu_key))
return -1;
if (le_key_k_offset(le_key_version(le_key), le_key) >
cpu_key_k_offset(cpu_key))
return 1;
if (cpu_key->key_length == 3)
return 0;
/* this part is needed only when tail conversion is in progress */
if (le_key_k_type(le_key_version(le_key), le_key) <
cpu_key_k_type(cpu_key))
return -1;
if (le_key_k_type(le_key_version(le_key), le_key) >
cpu_key_k_type(cpu_key))
return 1;
return 0;
}
static char * le_offset (struct key * key)
{
int version;
version = le_key_version (key);
if (le_key_k_type (version, key) == TYPE_DIRENTRY)
sprintf (off_buf, "%Lu(%Lu)",
(unsigned long long)GET_HASH_VALUE (le_key_k_offset (version, key)),
(unsigned long long)GET_GENERATION_NUMBER (le_key_k_offset (version, key)));
else
sprintf (off_buf, "0x%Lx", (unsigned long long)le_key_k_offset (version, key));
return off_buf;
}
inline void le_key2cpu_key(struct cpu_key *to, const struct reiserfs_key *from)
{
int version;
to->on_disk_key.k_dir_id = le32_to_cpu(from->k_dir_id);
to->on_disk_key.k_objectid = le32_to_cpu(from->k_objectid);
// find out version of the key
version = le_key_version(from);
to->version = version;
to->on_disk_key.k_offset = le_key_k_offset(version, from);
to->on_disk_key.k_type = le_key_k_type(version, from);
}
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;
}
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);
}
/* Allocates blocks for a file to fulfil write request.
Maps all unmapped but prepared pages from the list.
Updates metadata with newly allocated blocknumbers as needed */
int reiserfs_allocate_blocks_for_region(
struct reiserfs_transaction_handle *th,
struct inode *inode, /* Inode we work with */
loff_t pos, /* Writing position */
int num_pages, /* number of pages write going
to touch */
int write_bytes, /* amount of bytes to write */
struct page **prepared_pages, /* array of
prepared pages
*/
int blocks_to_allocate /* Amount of blocks we
need to allocate to
fit the data into file
*/
)
{
struct cpu_key key; // cpu key of item that we are going to deal with
struct item_head *ih; // pointer to item head that we are going to deal with
struct buffer_head *bh; // Buffer head that contains items that we are going to deal with
__u32 * item; // pointer to item we are going to deal with
INITIALIZE_PATH(path); // path to item, that we are going to deal with.
b_blocknr_t *allocated_blocks; // Pointer to a place where allocated blocknumbers would be stored.
reiserfs_blocknr_hint_t hint; // hint structure for block allocator.
size_t res; // return value of various functions that we call.
int curr_block; // current block used to keep track of unmapped blocks.
int i; // loop counter
int itempos; // position in item
unsigned int from = (pos & (PAGE_CACHE_SIZE - 1)); // writing position in
// first page
unsigned int to = ((pos + write_bytes - 1) & (PAGE_CACHE_SIZE - 1)) + 1; /* last modified byte offset in last page */
__u64 hole_size ; // amount of blocks for a file hole, if it needed to be created.
int modifying_this_item = 0; // Flag for items traversal code to keep track
// of the fact that we already prepared
// current block for journal
int will_prealloc = 0;
RFALSE(!blocks_to_allocate, "green-9004: tried to allocate zero blocks?");
/* only preallocate if this is a small write */
if (REISERFS_I(inode)->i_prealloc_count ||
(!(write_bytes & (inode->i_sb->s_blocksize -1)) &&
blocks_to_allocate <
REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize))
will_prealloc = REISERFS_SB(inode->i_sb)->s_alloc_options.preallocsize;
allocated_blocks = kmalloc((blocks_to_allocate + will_prealloc) *
sizeof(b_blocknr_t), GFP_NOFS);
/* First we compose a key to point at the writing position, we want to do
that outside of any locking region. */
make_cpu_key (&key, inode, pos+1, TYPE_ANY, 3/*key length*/);
/* If we came here, it means we absolutely need to open a transaction,
since we need to allocate some blocks */
reiserfs_write_lock(inode->i_sb); // Journaling stuff and we need that.
journal_begin(th, inode->i_sb, JOURNAL_PER_BALANCE_CNT * 3 + 1); // Wish I know if this number enough
reiserfs_update_inode_transaction(inode) ;
/* Look for the in-tree position of our write, need path for block allocator */
res = search_for_position_by_key(inode->i_sb, &key, &path);
if ( res == IO_ERROR ) {
res = -EIO;
goto error_exit;
}
/* Allocate blocks */
/* First fill in "hint" structure for block allocator */
hint.th = th; // transaction handle.
hint.path = &path; // Path, so that block allocator can determine packing locality or whatever it needs to determine.
hint.inode = inode; // Inode is needed by block allocator too.
hint.search_start = 0; // We have no hint on where to search free blocks for block allocator.
hint.key = key.on_disk_key; // on disk key of file.
hint.block = inode->i_blocks>>(inode->i_sb->s_blocksize_bits-9); // Number of disk blocks this file occupies already.
hint.formatted_node = 0; // We are allocating blocks for unformatted node.
hint.preallocate = will_prealloc;
/* Call block allocator to allocate blocks */
res = reiserfs_allocate_blocknrs(&hint, allocated_blocks, blocks_to_allocate, blocks_to_allocate);
if ( res != CARRY_ON ) {
if ( res == NO_DISK_SPACE ) {
/* We flush the transaction in case of no space. This way some
blocks might become free */
SB_JOURNAL(inode->i_sb)->j_must_wait = 1;
restart_transaction(th, inode, &path);
/* We might have scheduled, so search again */
res = search_for_position_by_key(inode->i_sb, &key, &path);
if ( res == IO_ERROR ) {
res = -EIO;
goto error_exit;
}
/* update changed info for hint structure. */
res = reiserfs_allocate_blocknrs(&hint, allocated_blocks, blocks_to_allocate, blocks_to_allocate);
if ( res != CARRY_ON ) {
res = -ENOSPC;
pathrelse(&path);
goto error_exit;
}
} else {
res = -ENOSPC;
pathrelse(&path);
goto error_exit;
}
}
#ifdef __BIG_ENDIAN
// Too bad, I have not found any way to convert a given region from
// cpu format to little endian format
{
int i;
for ( i = 0; i < blocks_to_allocate ; i++)
allocated_blocks[i]=cpu_to_le32(allocated_blocks[i]);
}
#endif
/* Blocks allocating well might have scheduled and tree might have changed,
let's search the tree again */
/* find where in the tree our write should go */
res = search_for_position_by_key(inode->i_sb, &key, &path);
if ( res == IO_ERROR ) {
res = -EIO;
goto error_exit_free_blocks;
}
bh = get_last_bh( &path ); // Get a bufferhead for last element in path.
ih = get_ih( &path ); // Get a pointer to last item head in path.
item = get_item( &path ); // Get a pointer to last item in path
/* Let's see what we have found */
if ( res != POSITION_FOUND ) { /* position not found, this means that we
might need to append file with holes
first */
// Since we are writing past the file's end, we need to find out if
// there is a hole that needs to be inserted before our writing
// position, and how many blocks it is going to cover (we need to
// populate pointers to file blocks representing the hole with zeros)
{
int item_offset = 1;
/*
* if ih is stat data, its offset is 0 and we don't want to
* add 1 to pos in the hole_size calculation
*/
if (is_statdata_le_ih(ih))
item_offset = 0;
hole_size = (pos + item_offset -
(le_key_k_offset( get_inode_item_key_version(inode),
&(ih->ih_key)) +
op_bytes_number(ih, inode->i_sb->s_blocksize))) >>
inode->i_sb->s_blocksize_bits;
}
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;
}
// if it is not first item of the body, then it is mergeable
static int indirect_is_left_mergeable(struct reiserfs_key *key,
unsigned long bsize)
{
int version = le_key_version(key);
return (le_key_k_offset(version, key) != 1);
}
static int direct_is_left_mergeable (struct key * key, unsigned long bsize)
{
int version = le_key_version (key);
return ((le_key_k_offset (version, key) & (bsize - 1)) != 1);
}
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;
}