static int ext2_readdir(struct file * filp,
void * dirent, filldir_t filldir)
{
int error = 0;
unsigned long offset, blk;
int i, num, stored;
struct buffer_head * bh, * tmp, * bha[16];
struct ext2_dir_entry_2 * de;
struct super_block * sb;
int err;
struct inode *inode = filp->f_dentry->d_inode;
if (!inode || !S_ISDIR(inode->i_mode))
return -EBADF;
sb = inode->i_sb;
stored = 0;
bh = NULL;
offset = filp->f_pos & (sb->s_blocksize - 1);
while (!error && !stored && filp->f_pos < inode->i_size) {
blk = (filp->f_pos) >> EXT2_BLOCK_SIZE_BITS(sb);
bh = ext2_bread (inode, blk, 0, &err);
if (!bh) {
ext2_error (sb, "ext2_readdir",
"directory #%lu contains a hole at offset %lu",
inode->i_ino, (unsigned long)filp->f_pos);
filp->f_pos += sb->s_blocksize - offset;
continue;
}
/*
* Do the readahead
*/
if (!offset) {
for (i = 16 >> (EXT2_BLOCK_SIZE_BITS(sb) - 9), num = 0;
i > 0; i--) {
tmp = ext2_getblk (inode, ++blk, 0, &err);
if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
bha[num++] = tmp;
else
brelse (tmp);
}
if (num) {
ll_rw_block (READA, num, bha);
for (i = 0; i < num; i++)
brelse (bha[i]);
}
}
revalidate:
/* If the dir block has changed since the last call to
* readdir(2), then we might be pointing to an invalid
* dirent right now. Scan from the start of the block
* to make sure. */
if (filp->f_version != inode->i_version) {
for (i = 0; i < sb->s_blocksize && i < offset; ) {
de = (struct ext2_dir_entry_2 *)
(bh->b_data + i);
/* It's too expensive to do a full
* dirent test each time round this
* loop, but we do have to test at
* least that it is non-zero. A
* failure will be detected in the
* dirent test below. */
if (le16_to_cpu(de->rec_len) < EXT2_DIR_REC_LEN(1))
break;
i += le16_to_cpu(de->rec_len);
}
offset = i;
filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
| offset;
filp->f_version = inode->i_version;
}
while (!error && filp->f_pos < inode->i_size
&& offset < sb->s_blocksize) {
de = (struct ext2_dir_entry_2 *) (bh->b_data + offset);
if (!ext2_check_dir_entry ("ext2_readdir", inode, de,
bh, offset)) {
/* On error, skip the f_pos to the
next block. */
filp->f_pos = (filp->f_pos & (sb->s_blocksize - 1))
+ sb->s_blocksize;
brelse (bh);
return stored;
}
offset += le16_to_cpu(de->rec_len);
if (le32_to_cpu(de->inode)) {
/* We might block in the next section
* if the data destination is
* currently swapped out. So, use a
* version stamp to detect whether or
* not the directory has been modified
* during the copy operation.
*/
unsigned long version = inode->i_version;
error = filldir(dirent, de->name,
de->name_len,
filp->f_pos, le32_to_cpu(de->inode));
if (error)
break;
if (version != inode->i_version)
goto revalidate;
stored ++;
}
filp->f_pos += le16_to_cpu(de->rec_len);
}
offset = 0;
brelse (bh);
}
UPDATE_ATIME(inode);
return 0;
}
static int ext2_readdir (struct inode * inode, struct file * filp,
struct dirent * dirent, int count)
{
unsigned long offset, blk;
int i, num;
struct buffer_head * bh, * tmp, * bha[16];
struct ext2_dir_entry * de;
struct super_block * sb;
int err;
if (!inode || !S_ISDIR(inode->i_mode))
return -EBADF;
sb = inode->i_sb;
while (filp->f_pos < inode->i_size) {
offset = filp->f_pos & (sb->s_blocksize - 1);
blk = (filp->f_pos) >> EXT2_BLOCK_SIZE_BITS(sb);
bh = ext2_bread (inode, blk, 0, &err);
if (!bh) {
filp->f_pos += sb->s_blocksize - offset;
continue;
}
/*
* Do the readahead
*/
if (!offset) {
for (i = 16 >> (EXT2_BLOCK_SIZE_BITS(sb) - 9), num = 0;
i > 0; i--) {
tmp = ext2_getblk (inode, ++blk, 0, &err);
if (tmp && !tmp->b_uptodate && !tmp->b_lock)
bha[num++] = tmp;
else
brelse (tmp);
}
if (num) {
ll_rw_block (READA, num, bha);
for (i = 0; i < num; i++)
brelse (bha[i]);
}
}
de = (struct ext2_dir_entry *) (offset + bh->b_data);
while (offset < sb->s_blocksize && filp->f_pos < inode->i_size) {
if (!ext2_check_dir_entry ("ext2_readdir", inode, de,
bh, offset)) {
brelse (bh);
return 0;
}
offset += de->rec_len;
filp->f_pos += de->rec_len;
if (de->inode) {
memcpy_tofs (dirent->d_name, de->name,
de->name_len);
put_fs_long (de->inode, &dirent->d_ino);
put_fs_byte (0, de->name_len + dirent->d_name);
put_fs_word (de->name_len, &dirent->d_reclen);
dcache_add(inode, de->name, de->name_len,
de->inode);
i = de->name_len;
brelse (bh);
if (!IS_RDONLY(inode)) {
inode->i_atime = CURRENT_TIME;
inode->i_dirt = 1;
}
return i;
}
de = (struct ext2_dir_entry *) ((char *) de +
de->rec_len);
}
brelse (bh);
}
if (!IS_RDONLY(inode)) {
inode->i_atime = CURRENT_TIME;
inode->i_dirt = 1;
}
return 0;
}
static int ext2_readdir (struct inode * inode, struct file * filp,
struct dirent * dirent, int count)
{
unsigned long offset, blk;
int i, num, stored, dlen;
struct buffer_head * bh, * tmp, * bha[16];
struct ext2_dir_entry * de;
struct super_block * sb;
int err, version;
if (!inode || !S_ISDIR(inode->i_mode))
return -EBADF;
sb = inode->i_sb;
stored = 0;
bh = NULL;
offset = filp->f_pos & (sb->s_blocksize - 1);
while (count > 0 && !stored && filp->f_pos < inode->i_size) {
blk = (filp->f_pos) >> EXT2_BLOCK_SIZE_BITS(sb);
bh = ext2_bread (inode, blk, 0, &err);
if (!bh) {
filp->f_pos += sb->s_blocksize - offset;
continue;
}
/*
* Do the readahead
*/
if (!offset) {
for (i = 16 >> (EXT2_BLOCK_SIZE_BITS(sb) - 9), num = 0;
i > 0; i--) {
tmp = ext2_getblk (inode, ++blk, 0, &err);
if (tmp && !tmp->b_uptodate && !tmp->b_lock)
bha[num++] = tmp;
else
brelse (tmp);
}
if (num) {
ll_rw_block (READA, num, bha);
for (i = 0; i < num; i++)
brelse (bha[i]);
}
}
revalidate:
/* If the dir block has changed since the last call to
* readdir(2), then we might be pointing to an invalid
* dirent right now. Scan from the start of the block
* to make sure. */
if (filp->f_version != inode->i_version) {
for (i = 0; i < sb->s_blocksize && i < offset; ) {
de = (struct ext2_dir_entry *)
(bh->b_data + i);
/* It's too expensive to do a full
* dirent test each time round this
* loop, but we do have to test at
* least that it is non-zero. A
* failure will be detected in the
* dirent test below. */
if (de->rec_len < EXT2_DIR_REC_LEN(1))
break;
i += de->rec_len;
}
offset = i;
filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
| offset;
filp->f_version = inode->i_version;
}
while (count > 0 && filp->f_pos < inode->i_size
&& offset < sb->s_blocksize) {
de = (struct ext2_dir_entry *) (bh->b_data + offset);
if (!ext2_check_dir_entry ("ext2_readdir", inode, de,
bh, offset)) {
/* On error, skip the f_pos to the
next block. */
filp->f_pos = (filp->f_pos & (sb->s_blocksize - 1))
+ sb->s_blocksize;
brelse (bh);
return stored;
}
if (de->inode) {
dlen = ROUND_UP(NAME_OFFSET(dirent)
+ de->name_len + 1);
/* Old libc libraries always use a
count of 1. */
if (count == 1 && !stored)
count = dlen;
if (count < dlen) {
count = 0;
break;
}
/* We might block in the next section
* if the data destination is
* currently swapped out. So, use a
* version stamp to detect whether or
* not the directory has been modified
* during the copy operation. */
version = inode->i_version;
i = de->name_len;
memcpy_tofs (dirent->d_name, de->name, i);
put_fs_long (de->inode, &dirent->d_ino);
put_fs_byte (0, dirent->d_name + i);
put_fs_word (i, &dirent->d_reclen);
put_fs_long (dlen, &dirent->d_off);
if (version != inode->i_version)
goto revalidate;
dcache_add(inode, de->name, de->name_len,
de->inode);
stored += dlen;
count -= dlen;
((char *) dirent) += dlen;
}
offset += de->rec_len;
filp->f_pos += de->rec_len;
}
offset = 0;
brelse (bh);
}
if (!IS_RDONLY(inode)) {
inode->i_atime = CURRENT_TIME;
inode->i_dirt = 1;
}
return stored;
}
