struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
unsigned int block_group,
struct buffer_head ** bh)
{
unsigned long group_desc;
unsigned long offset;
struct ext2_group_desc * desc;
struct ext2_sb_info *sbi = EXT2_SB(sb);
if (block_group >= sbi->s_groups_count) {
ext2_error (sb, "ext2_get_group_desc",
"block_group >= groups_count - "
"block_group = %d, groups_count = %lu",
block_group, sbi->s_groups_count);
return NULL;
}
group_desc = block_group >> EXT2_DESC_PER_BLOCK_BITS(sb);
offset = block_group & (EXT2_DESC_PER_BLOCK(sb) - 1);
if (!sbi->s_group_desc[group_desc]) {
ext2_error (sb, "ext2_get_group_desc",
"Group descriptor not loaded - "
"block_group = %d, group_desc = %lu, desc = %lu",
block_group, group_desc, offset);
return NULL;
}
desc = (struct ext2_group_desc *) sbi->s_group_desc[group_desc]->b_data;
if (bh)
*bh = sbi->s_group_desc[group_desc];
return desc + offset;
}
static struct buffer_head *
read_block_bitmap(struct super_block *sb, unsigned int block_group)
{
struct ext2_group_desc * desc;
struct buffer_head * bh = NULL;
ext2_fsblk_t bitmap_blk;
desc = ext2_get_group_desc(sb, block_group, NULL);
if (!desc)
return NULL;
bitmap_blk = le32_to_cpu(desc->bg_block_bitmap);
bh = sb_getblk(sb, bitmap_blk);
if (unlikely(!bh)) {
ext2_error(sb, __func__,
"Cannot read block bitmap - "
"block_group = %d, block_bitmap = %u",
block_group, le32_to_cpu(desc->bg_block_bitmap));
return NULL;
}
if (likely(bh_uptodate_or_lock(bh)))
return bh;
if (bh_submit_read(bh) < 0) {
brelse(bh);
ext2_error(sb, __func__,
"Cannot read block bitmap - "
"block_group = %d, block_bitmap = %u",
block_group, le32_to_cpu(desc->bg_block_bitmap));
return NULL;
}
ext2_valid_block_bitmap(sb, desc, block_group, bh);
return bh;
}
void
ext2_check_inodes_bitmap ()
{
int i;
struct ext2_group_desc *gdp;
unsigned long desc_count, bitmap_count, x;
pthread_spin_lock (&global_lock);
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < groups_count; i++)
{
void *bh;
gdp = group_desc (i);
desc_count += gdp->bg_free_inodes_count;
bh = disk_cache_block_ref (gdp->bg_inode_bitmap);
x = count_free (bh, sblock->s_inodes_per_group / 8);
disk_cache_block_deref (bh);
if (gdp->bg_free_inodes_count != x)
ext2_error ("wrong free inodes count in group %d, "
"stored = %d, counted = %lu",
i, gdp->bg_free_inodes_count, x);
bitmap_count += x;
}
if (sblock->s_free_inodes_count != bitmap_count)
ext2_error ("wrong free inodes count in super block, "
"stored = %lu, counted = %lu",
(unsigned long) sblock->s_free_inodes_count, bitmap_count);
pthread_spin_unlock (&global_lock);
}
/* Called at mount-time, super-block is locked */
void ext2_check_inodes_bitmap (struct super_block * sb)
{
struct ext2_super_block * es = sb->u.ext2_sb.s_es;
unsigned long desc_count = 0, bitmap_count = 0;
int i;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
struct ext2_group_desc *desc = ext2_get_group_desc(sb, i, NULL);
struct buffer_head *bh;
unsigned x;
if (!desc)
continue;
desc_count += le16_to_cpu(desc->bg_free_inodes_count);
bh = load_inode_bitmap (sb, i);
if (IS_ERR(bh))
continue;
x = ext2_count_free (bh, EXT2_INODES_PER_GROUP(sb) / 8);
if (le16_to_cpu(desc->bg_free_inodes_count) != x)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in group %d, "
"stored = %d, counted = %lu", i,
le16_to_cpu(desc->bg_free_inodes_count), x);
bitmap_count += x;
}
if (le32_to_cpu(es->s_free_inodes_count) != bitmap_count)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in super block, "
"stored = %lu, counted = %lu",
(unsigned long)le32_to_cpu(es->s_free_inodes_count),
bitmap_count);
}
static int ext2_check_descriptors (struct super_block * sb)
{
int i;
int desc_block = 0;
struct ext2_sb_info *sbi = EXT2_SB(sb);
struct ext2_group_desc * gdp = NULL;
ext2_debug ("Checking group descriptors");
for (i = 0; i < sbi->s_groups_count; i++)
{
ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
ext2_fsblk_t last_block;
if (i == sbi->s_groups_count - 1)
last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
else
last_block = first_block +
(EXT2_BLOCKS_PER_GROUP(sb) - 1);
if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
le32_to_cpu(gdp->bg_block_bitmap) > last_block)
{
ext2_error (sb, "ext2_check_descriptors",
"Block bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
{
ext2_error (sb, "ext2_check_descriptors",
"Inode bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
last_block)
{
ext2_error (sb, "ext2_check_descriptors",
"Inode table for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
return 0;
}
gdp++;
}
return 1;
}
static int read_inode_bitmap (struct super_block * sb,
unsigned long block_group,
unsigned int bitmap_nr)
{
struct ext2_group_desc * gdp;
struct buffer_head * bh;
int retval = 0;
int bs = BYTE_SWAP(sb->u.ext2_sb.s_byte_swapped);
gdp = get_group_desc (sb, block_group, NULL);
bh = bread (sb->s_dev, e_swab (bs, gdp->bg_inode_bitmap),
sb->s_blocksize);
if (!bh) {
ext2_error (sb, "read_inode_bitmap",
"Cannot read inode bitmap - "
"block_group = %lu, inode_bitmap = %lu",
block_group,
(unsigned long) e_swab (bs, gdp->bg_inode_bitmap));
retval = -EIO;
}
/*
* On IO error, just leave a zero in the superblock's block pointer for
* this group. The IO will be retried next time.
*/
sb->u.ext2_sb.s_inode_bitmap_number[bitmap_nr] = block_group;
sb->u.ext2_sb.s_inode_bitmap[bitmap_nr] = bh;
return retval;
}
int ext2_check_dir_entry (const char * function, struct inode * dir,
struct ext2_dir_entry_2 * de,
struct buffer_head * bh,
unsigned long offset)
{
const char * error_msg = NULL;
if (le16_to_cpu(de->rec_len) < EXT2_DIR_REC_LEN(1))
error_msg = "rec_len is smaller than minimal";
else if (le16_to_cpu(de->rec_len) % 4 != 0)
error_msg = "rec_len % 4 != 0";
else if (le16_to_cpu(de->rec_len) < EXT2_DIR_REC_LEN(de->name_len))
error_msg = "rec_len is too small for name_len";
else if (dir && ((char *) de - bh->b_data) + le16_to_cpu(de->rec_len) >
dir->i_sb->s_blocksize)
error_msg = "directory entry across blocks";
else if (dir && le32_to_cpu(de->inode) > le32_to_cpu(dir->i_sb->u.ext2_sb.s_es->s_inodes_count))
error_msg = "inode out of bounds";
if (error_msg != NULL)
ext2_error (dir->i_sb, function, "bad entry in directory #%lu: %s - "
"offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
dir->i_ino, error_msg, offset,
(unsigned long) le32_to_cpu(de->inode),
le16_to_cpu(de->rec_len), de->name_len);
return error_msg == NULL ? 1 : 0;
}
static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
{
struct inode * inode;
ino_t ino;
if (dentry->d_name.len > EXT2_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
ino = ext2_inode_by_name(dir, &dentry->d_name);
inode = NULL;
if (ino) {
inode = ext2_iget(dir->i_sb, ino);
<<<<<<< HEAD
if (IS_ERR(inode)) {
=======
if (unlikely(IS_ERR(inode))) {
>>>>>>> 296c66da8a02d52243f45b80521febece5ed498a
if (PTR_ERR(inode) == -ESTALE) {
ext2_error(dir->i_sb, __func__,
"deleted inode referenced: %lu",
(unsigned long) ino);
return ERR_PTR(-EIO);
} else {
return ERR_CAST(inode);
}
}
static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
{
struct inode * inode;
ino_t ino;
if (dentry->d_name.len > EXT2_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
ino = ext2_inode_by_name(dir, &dentry->d_name);
inode = NULL;
if (ino) {
inode = ext2_iget(dir->i_sb, ino);
if (unlikely(IS_ERR(inode))) {
if (PTR_ERR(inode) == -ESTALE) {
ext2_error(dir->i_sb, __func__,
"deleted inode referenced: %lu",
(unsigned long) ino);
return ERR_PTR(-EIO);
} else {
return ERR_CAST(inode);
}
}
}
return d_splice_alias(inode, dentry);
}
int ext2_fsync(struct file *file, int datasync)
{
int ret;
struct inode *inode = file->f_mapping->host;
ino_t ino = inode->i_ino;
struct super_block *sb = inode->i_sb;
struct address_space *sb_mapping = sb->s_bdev->bd_inode->i_mapping;
struct buffer_head *bh;
struct ext2_inode *raw_inode;
ret = generic_file_fsync(file, datasync);
if (ret == -EIO || test_and_clear_bit(AS_EIO, &sb_mapping->flags)) {
/* We don't really know where the IO error happened... */
ext2_error(sb, __func__,
"detected IO error when writing metadata buffers");
return -EIO;
}
raw_inode = ext2_get_inode(sb, ino, &bh);
if (IS_ERR(raw_inode))
return -EIO;
sync_dirty_buffer(bh);
if (buffer_req(bh) && !buffer_uptodate(bh)) {
printk ("IO error syncing ext2 inode [%s:%08lx]\n",
sb->s_id, (unsigned long) ino);
ret = -EIO;
}
brelse (bh);
return ret;
}
/*
* Read the inode allocation bitmap for a given block_group, reading
* into the specified slot in the superblock's bitmap cache.
*
* Return >=0 on success or a -ve error code.
*/
static int read_inode_bitmap (struct super_block * sb,
unsigned long block_group,
unsigned int bitmap_nr)
{
struct ext2_group_desc * gdp;
struct buffer_head * bh = NULL;
int retval = 0;
gdp = ext2_get_group_desc (sb, block_group, NULL);
if (!gdp) {
retval = -EIO;
goto error_out;
}
bh = bread (sb->s_dev, le32_to_cpu(gdp->bg_inode_bitmap), sb->s_blocksize);
if (!bh) {
ext2_error (sb, "read_inode_bitmap",
"Cannot read inode bitmap - "
"block_group = %lu, inode_bitmap = %lu",
block_group, (unsigned long) gdp->bg_inode_bitmap);
retval = -EIO;
}
/*
* On IO error, just leave a zero in the superblock's block pointer for
* this group. The IO will be retried next time.
*/
error_out:
sb->u.ext2_sb.s_inode_bitmap_number[bitmap_nr] = block_group;
sb->u.ext2_sb.s_inode_bitmap[bitmap_nr] = bh;
return retval;
}
int ext2_check_dir_entry (char * function, struct inode * dir,
struct ext2_dir_entry * de, struct buffer_head * bh,
unsigned long offset)
{
char * error_msg = NULL;
if (de->rec_len < EXT2_DIR_REC_LEN(1))
error_msg = "rec_len is smaller than minimal";
else if (de->rec_len % 4 != 0)
error_msg = "rec_len % 4 != 0";
else if (de->rec_len < EXT2_DIR_REC_LEN(de->name_len))
error_msg = "rec_len is too small for name_len";
else if (dir && ((char *) de - bh->b_data) + de->rec_len >
dir->i_sb->s_blocksize)
error_msg = "directory entry across blocks";
else if (dir && de->inode > dir->i_sb->u.ext2_sb.s_es->s_inodes_count)
error_msg = "inode out of bounds";
if (error_msg != NULL)
ext2_error (dir->i_sb, function, "bad directory entry: %s\n"
"offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
error_msg, offset, de->inode, de->rec_len,
de->name_len);
return error_msg == NULL ? 1 : 0;
}
/* alloc a new block */
int ext2_alloc_block ( unsigned int goal)
{
unsigned int block;
unsigned int block_group;
unsigned int bit;
struct ext2_group_desc *desc;
struct ext2_sb_info * sbi = EXT2_SBI();
void *bitmap;
block_group = ext2_get_group_num (goal, BLOCK);
bit = ext2_get_group_offset (goal, BLOCK);
bitmap = ext2_read_block_bitmap (block_group);
block = ext2_grab_block (bitmap, bit);
if ( !block)
ext2_error ("no free blocks any more");
desc = ext2_get_group_desc (block_group);
desc->bg_free_blocks_count --;
sbi->s_free_blocks_count --;
ext2_set_bit (bitmap, block);
return block;
}
static int ext2_check_descriptors (struct super_block * sb)
{
int i;
int desc_block = 0;
unsigned long block = le32_to_cpu(sb->u.ext2_sb.s_es->s_first_data_block);
struct ext2_group_desc * gdp = NULL;
ext2_debug ("Checking group descriptors");
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++)
{
if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
gdp = (struct ext2_group_desc *) sb->u.ext2_sb.s_group_desc[desc_block++]->b_data;
if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Block bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Inode bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_table) < block ||
le32_to_cpu(gdp->bg_inode_table) + sb->u.ext2_sb.s_itb_per_group >=
block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Inode table for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
return 0;
}
block += EXT2_BLOCKS_PER_GROUP(sb);
gdp++;
}
return 1;
}
int ext2_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
int ret;
struct super_block *sb = file->f_mapping->host->i_sb;
ret = generic_file_fsync(file, start, end, datasync);
if (ret == -EIO)
/* We don't really know where the IO error happened... */
ext2_error(sb, __func__,
"detected IO error when writing metadata buffers");
return ret;
}
void ext2_check_inodes_bitmap (struct super_block * sb)
{
struct ext2_super_block * es;
unsigned long desc_count, bitmap_count, x;
int bitmap_nr;
struct ext2_group_desc * gdp;
int i;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
gdp = ext2_get_group_desc (sb, i, NULL);
if (!gdp)
continue;
desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
bitmap_nr = load_inode_bitmap (sb, i);
if (bitmap_nr < 0)
continue;
x = ext2_count_free (sb->u.ext2_sb.s_inode_bitmap[bitmap_nr],
EXT2_INODES_PER_GROUP(sb) / 8);
if (le16_to_cpu(gdp->bg_free_inodes_count) != x)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in group %d, "
"stored = %d, counted = %lu", i,
le16_to_cpu(gdp->bg_free_inodes_count), x);
bitmap_count += x;
}
if (le32_to_cpu(es->s_free_inodes_count) != bitmap_count)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in super block, "
"stored = %lu, counted = %lu",
(unsigned long) le32_to_cpu(es->s_free_inodes_count),
bitmap_count);
unlock_super (sb);
}
/* Free node NP; the on disk copy has already been synced with
diskfs_node_update (where NP->dn_stat.st_mode was 0). It's
mode used to be OLD_MODE. */
void
diskfs_free_node (struct node *np, mode_t old_mode)
{
char *bh;
unsigned long block_group;
unsigned long bit;
struct ext2_group_desc *gdp;
ino_t inum = np->cache_id;
assert (!diskfs_readonly);
ext2_debug ("freeing inode %u", inum);
pthread_spin_lock (&global_lock);
if (inum < EXT2_FIRST_INO (sblock) || inum > sblock->s_inodes_count)
{
ext2_error ("reserved inode or nonexistent inode: %Ld", inum);
pthread_spin_unlock (&global_lock);
return;
}
block_group = (inum - 1) / sblock->s_inodes_per_group;
bit = (inum - 1) % sblock->s_inodes_per_group;
gdp = group_desc (block_group);
bh = disk_cache_block_ref (gdp->bg_inode_bitmap);
if (!clear_bit (bit, bh))
ext2_warning ("bit already cleared for inode %Ld", inum);
else
{
disk_cache_block_ref_ptr (bh);
record_global_poke (bh);
gdp->bg_free_inodes_count++;
if (S_ISDIR (old_mode))
gdp->bg_used_dirs_count--;
disk_cache_block_ref_ptr (gdp);
record_global_poke (gdp);
sblock->s_free_inodes_count++;
}
disk_cache_block_deref (bh);
sblock_dirty = 1;
pthread_spin_unlock (&global_lock);
alloc_sync(0);
}
int ext2_fsync(struct file *file, struct dentry *dentry, int datasync)
{
int ret;
struct super_block *sb = dentry->d_inode->i_sb;
struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
ret = simple_fsync(file, dentry, datasync);
if (ret == -EIO || test_and_clear_bit(AS_EIO, &mapping->flags)) {
/* We don't really know where the IO error happened... */
ext2_error(sb, __func__,
"detected IO error when writing metadata buffers");
ret = -EIO;
}
return ret;
}
/*
* Read the bitmap for a given block_group, reading into the specified
* slot in the superblock's bitmap cache.
*
*/
void * ext2_read_block_bitmap(unsigned int block_group)
{
struct ext2_group_desc * desc;
void * bitmap = NULL;
desc = ext2_get_group_desc (block_group);
if (!desc)
goto error_out;
bitmap = (void *)(EXT2_BITMAP_BUFFER + (block_group << 1) * EXT2_BLOCK_SIZE);
if (!bitmap)
ext2_error ("read_block_bitmap",
"Cannot read block bitmap - "
"block_group = %d, block_bitmap = %u",
block_group, desc->bg_block_bitmap);
error_out:
return bitmap;
}
static int ext2_valid_block_bitmap(struct super_block *sb,
struct ext2_group_desc *desc,
unsigned int block_group,
struct buffer_head *bh)
{
ext2_grpblk_t offset;
ext2_grpblk_t next_zero_bit;
ext2_fsblk_t bitmap_blk;
ext2_fsblk_t group_first_block;
group_first_block = ext2_group_first_block_no(sb, block_group);
/* check whether block bitmap block number is set */
bitmap_blk = le32_to_cpu(desc->bg_block_bitmap);
offset = bitmap_blk - group_first_block;
if (!ext2_test_bit(offset, bh->b_data))
/* bad block bitmap */
goto err_out;
/* check whether the inode bitmap block number is set */
bitmap_blk = le32_to_cpu(desc->bg_inode_bitmap);
offset = bitmap_blk - group_first_block;
if (!ext2_test_bit(offset, bh->b_data))
/* bad block bitmap */
goto err_out;
/* check whether the inode table block number is set */
bitmap_blk = le32_to_cpu(desc->bg_inode_table);
offset = bitmap_blk - group_first_block;
next_zero_bit = ext2_find_next_zero_bit(bh->b_data,
offset + EXT2_SB(sb)->s_itb_per_group,
offset);
if (next_zero_bit >= offset + EXT2_SB(sb)->s_itb_per_group)
/* good bitmap for inode tables */
return 1;
err_out:
ext2_error(sb, __func__,
"Invalid block bitmap - "
"block_group = %d, block = %lu",
block_group, bitmap_blk);
return 0;
}
/*
* Read the inode allocation bitmap for a given block_group, reading
* into the specified slot in the superblock's bitmap cache.
*
* Return buffer_head of bitmap on success or NULL.
*/
static struct buffer_head *read_inode_bitmap (struct super_block * sb,
unsigned long block_group)
{
struct ext2_group_desc *desc;
struct buffer_head *bh = NULL;
desc = ext2_get_group_desc(sb, block_group, NULL);
if (!desc)
goto error_out;
bh = sb_bread(sb, le32_to_cpu(desc->bg_inode_bitmap));
if (!bh)
ext2_error (sb, "read_inode_bitmap",
"Cannot read inode bitmap - "
"block_group = %lu, inode_bitmap = %lu",
block_group, (unsigned long) desc->bg_inode_bitmap);
error_out:
return bh;
}
/* free the goal block, clean it */
void ext2_free_block(unsigned int block)
{
unsigned int block_group;
unsigned int bit;
struct ext2_group_desc *desc;
struct ext2_sb_info * sbi = EXT2_SBI();
void * bitmap;
block_group = ext2_get_group_num (block, BLOCK);
bit = ext2_get_group_offset (block, BLOCK);
desc = ext2_get_group_desc (block_group);
bitmap = ext2_read_block_bitmap (block_group);
if ( !ext2_clear_bit(bitmap, bit) )
ext2_error("bit %d (%d) alread cleard", bit, block_group);
desc->bg_free_blocks_count ++;
sbi->s_free_blocks_count ++;
}
static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)
{
struct inode * inode;
ino_t ino;
if (dentry->d_name.len > EXT2_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
ino = ext2_inode_by_name(dir, &dentry->d_name);
inode = NULL;
if (ino) {
inode = ext2_iget(dir->i_sb, ino);
if (inode == ERR_PTR(-ESTALE)) {
ext2_error(dir->i_sb, __func__,
"deleted inode referenced: %lu",
(unsigned long) ino);
return ERR_PTR(-EIO);
}
}
return d_splice_alias(inode, dentry);
}
void ext2_free_inode (struct inode * inode)
{
struct super_block * sb;
struct buffer_head * bh;
struct buffer_head * bh2;
unsigned long block_group;
unsigned long bit;
int bitmap_nr;
int bs;
struct ext2_group_desc * gdp;
struct ext2_super_block * es;
if (!inode)
return;
if (!inode->i_dev) {
printk ("ext2_free_inode: inode has no device\n");
return;
}
if (inode->i_count > 1) {
printk ("ext2_free_inode: inode has count=%ld\n",
inode->i_count);
return;
}
if (inode->i_nlink) {
printk ("ext2_free_inode: inode has nlink=%d\n",
inode->i_nlink);
return;
}
sb = inode->i_sb;
if (!sb) {
printk("ext2_free_inode: inode on nonexistent device\n");
return;
}
ext2_debug ("freeing inode %lu\n", inode->i_ino);
/* We need to kill quota references now, before grabbing the
* superblock lock because writing the quota out to disk
* may need to lock the superblock as well.
*
* It is safe to do this early instead of the original
* places because we cannot be here in ext2_free_inode
* if any other references to this inode exist at all.
*
* Based upon a 2.1.x fix by Bill Hawes. --DaveM
*/
if (sb->dq_op) {
sb->dq_op->free_inode (inode, 1);
if (IS_WRITABLE (inode))
sb->dq_op->drop(inode);
}
lock_super (sb);
bs = BYTE_SWAP(inode->i_sb->u.ext2_sb.s_byte_swapped);
if (inode->i_ino < EXT2_FIRST_INO(sb) ||
inode->i_ino > e_swab (bs, sb->u.ext2_sb.s_es->s_inodes_count)) {
ext2_error (sb, "free_inode",
"reserved inode or nonexistent inode");
unlock_super (sb);
return;
}
es = sb->u.ext2_sb.s_es;
block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(sb);
bit = (inode->i_ino - 1) % EXT2_INODES_PER_GROUP(sb);
bitmap_nr = load_inode_bitmap (sb, block_group);
if (bitmap_nr < 0) {
unlock_super (sb);
return;
}
bh = sb->u.ext2_sb.s_inode_bitmap[bitmap_nr];
if (!ext2_clear_bit (bit, bh->b_data))
ext2_warning (sb, "ext2_free_inode",
"bit already cleared for inode %lu", inode->i_ino);
else {
gdp = get_group_desc (sb, block_group, &bh2);
e_set_swab (bs, gdp->bg_free_inodes_count,
e_swab (bs, gdp->bg_free_inodes_count) + 1);
if (S_ISDIR(inode->i_mode))
e_set_swab (bs, gdp->bg_used_dirs_count,
e_swab (bs, gdp->bg_used_dirs_count) - 1);
mark_buffer_dirty(bh2, 1);
e_set_swab (bs, es->s_free_inodes_count,
e_swab (bs, es->s_free_inodes_count) + 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
inode->i_dirt = 0;
}
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
sb->s_dirt = 1;
clear_inode (inode);
unlock_super (sb);
}
/*
* NOTE! When we get the inode, we're the only people
* that have access to it, and as such there are no
* race conditions we have to worry about. The inode
* is not on the hash-lists, and it cannot be reached
* through the filesystem because the directory entry
* has been deleted earlier.
*
* HOWEVER: we must make sure that we get no aliases,
* which means that we have to call "clear_inode()"
* _before_ we mark the inode not in use in the inode
* bitmaps. Otherwise a newly created file might use
* the same inode number (not actually the same pointer
* though), and then we'd have two inodes sharing the
* same inode number and space on the harddisk.
*/
void ext2_free_inode (struct inode * inode)
{
struct super_block * sb = inode->i_sb;
int is_directory;
unsigned long ino;
struct buffer_head * bh;
struct buffer_head * bh2;
unsigned long block_group;
unsigned long bit;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_super_block * es;
if (!inode->i_dev) {
printk ("ext2_free_inode: inode has no device\n");
return;
}
if (inode->i_count > 1) {
printk ("ext2_free_inode: inode has count=%d\n", inode->i_count);
return;
}
if (inode->i_nlink) {
printk ("ext2_free_inode: inode has nlink=%d\n",
(int) inode->i_nlink);
return;
}
if (!sb) {
printk("ext2_free_inode: inode on nonexistent device\n");
return;
}
ino = inode->i_ino;
ext2_debug ("freeing inode %lu\n", ino);
/*
* Note: we must free any quota before locking the superblock,
* as writing the quota to disk may need the lock as well.
*/
DQUOT_FREE_INODE(sb, inode);
DQUOT_DROP(inode);
lock_super (sb);
es = sb->u.ext2_sb.s_es;
if (ino < EXT2_FIRST_INO(sb) ||
ino > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "free_inode",
"reserved inode or nonexistent inode");
goto error_return;
}
block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
bit = (ino - 1) % EXT2_INODES_PER_GROUP(sb);
bitmap_nr = load_inode_bitmap (sb, block_group);
if (bitmap_nr < 0)
goto error_return;
bh = sb->u.ext2_sb.s_inode_bitmap[bitmap_nr];
is_directory = S_ISDIR(inode->i_mode);
/* Do this BEFORE marking the inode not in use */
clear_inode (inode);
/* Ok, now we can actually update the inode bitmaps.. */
if (!ext2_clear_bit (bit, bh->b_data))
ext2_warning (sb, "ext2_free_inode",
"bit already cleared for inode %lu", ino);
else {
gdp = ext2_get_group_desc (sb, block_group, &bh2);
if (gdp) {
gdp->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) + 1);
if (is_directory)
gdp->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) - 1);
}
mark_buffer_dirty(bh2, 1);
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) + 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
}
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
sb->s_dirt = 1;
error_return:
unlock_super (sb);
}
struct inode * ext2_new_inode (const struct inode * dir, int mode)
{
struct super_block * sb;
struct buffer_head * bh;
struct buffer_head * bh2;
int group, i;
ino_t ino;
struct inode * inode;
struct ext2_group_desc * desc;
struct ext2_super_block * es;
int err;
sb = dir->i_sb;
inode = new_inode(sb);
if (!inode)
return ERR_PTR(-ENOMEM);
lock_super (sb);
es = sb->u.ext2_sb.s_es;
repeat:
if (S_ISDIR(mode))
group = find_group_dir(sb, dir->u.ext2_i.i_block_group);
else
group = find_group_other(sb, dir->u.ext2_i.i_block_group);
err = -ENOSPC;
if (group == -1)
goto fail;
err = -EIO;
bh = load_inode_bitmap (sb, group);
if (IS_ERR(bh))
goto fail2;
i = ext2_find_first_zero_bit ((unsigned long *) bh->b_data,
EXT2_INODES_PER_GROUP(sb));
if (i >= EXT2_INODES_PER_GROUP(sb))
goto bad_count;
ext2_set_bit (i, bh->b_data);
mark_buffer_dirty(bh);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
ino = group * EXT2_INODES_PER_GROUP(sb) + i + 1;
if (ino < EXT2_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "ext2_new_inode",
"reserved inode or inode > inodes count - "
"block_group = %d,inode=%ld", group, ino);
err = -EIO;
goto fail2;
}
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) - 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh);
sb->s_dirt = 1;
inode->i_uid = current->fsuid;
if (test_opt (sb, GRPID))
inode->i_gid = dir->i_gid;
else if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
mode |= S_ISGID;
} else
inode->i_gid = current->fsgid;
inode->i_mode = mode;
inode->i_ino = ino;
inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size (for stat), not the fs block size */
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->u.ext2_i.i_new_inode = 1;
inode->u.ext2_i.i_flags = dir->u.ext2_i.i_flags & ~EXT2_BTREE_FL;
if (S_ISLNK(mode))
inode->u.ext2_i.i_flags &= ~(EXT2_IMMUTABLE_FL|EXT2_APPEND_FL);
inode->u.ext2_i.i_block_group = group;
if (inode->u.ext2_i.i_flags & EXT2_SYNC_FL)
inode->i_flags |= S_SYNC;
insert_inode_hash(inode);
inode->i_generation = event++;
mark_inode_dirty(inode);
unlock_super (sb);
if(DQUOT_ALLOC_INODE(inode)) {
DQUOT_DROP(inode);
inode->i_flags |= S_NOQUOTA;
inode->i_nlink = 0;
iput(inode);
return ERR_PTR(-EDQUOT);
}
ext2_debug ("allocating inode %lu\n", inode->i_ino);
return inode;
fail2:
desc = ext2_get_group_desc (sb, group, &bh2);
desc->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) + 1);
if (S_ISDIR(mode))
desc->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) - 1);
mark_buffer_dirty(bh2);
fail:
unlock_super(sb);
make_bad_inode(inode);
iput(inode);
return ERR_PTR(err);
bad_count:
ext2_error (sb, "ext2_new_inode",
"Free inodes count corrupted in group %d",
group);
/* Is it really ENOSPC? */
err = -ENOSPC;
if (sb->s_flags & MS_RDONLY)
goto fail;
desc = ext2_get_group_desc (sb, group, &bh2);
desc->bg_free_inodes_count = 0;
mark_buffer_dirty(bh2);
goto repeat;
}
/*
* NOTE! When we get the inode, we're the only people
* that have access to it, and as such there are no
* race conditions we have to worry about. The inode
* is not on the hash-lists, and it cannot be reached
* through the filesystem because the directory entry
* has been deleted earlier.
*
* HOWEVER: we must make sure that we get no aliases,
* which means that we have to call "clear_inode()"
* _before_ we mark the inode not in use in the inode
* bitmaps. Otherwise a newly created file might use
* the same inode number (not actually the same pointer
* though), and then we'd have two inodes sharing the
* same inode number and space on the harddisk.
*/
void ext2_free_inode (struct inode * inode)
{
struct super_block * sb = inode->i_sb;
int is_directory;
unsigned long ino;
struct buffer_head * bh;
struct buffer_head * bh2;
unsigned long block_group;
unsigned long bit;
struct ext2_group_desc * desc;
struct ext2_super_block * es;
ino = inode->i_ino;
ext2_debug ("freeing inode %lu\n", ino);
/*
* Note: we must free any quota before locking the superblock,
* as writing the quota to disk may need the lock as well.
*/
if (!is_bad_inode(inode)) {
/* Quota is already initialized in iput() */
DQUOT_FREE_INODE(inode);
DQUOT_DROP(inode);
}
lock_super (sb);
es = sb->u.ext2_sb.s_es;
is_directory = S_ISDIR(inode->i_mode);
/* Do this BEFORE marking the inode not in use or returning an error */
clear_inode (inode);
if (ino < EXT2_FIRST_INO(sb) ||
ino > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "ext2_free_inode",
"reserved or nonexistent inode %lu", ino);
goto error_return;
}
block_group = (ino - 1) / EXT2_INODES_PER_GROUP(sb);
bit = (ino - 1) % EXT2_INODES_PER_GROUP(sb);
bh = load_inode_bitmap (sb, block_group);
if (IS_ERR(bh))
goto error_return;
/* Ok, now we can actually update the inode bitmaps.. */
if (!ext2_clear_bit (bit, bh->b_data))
ext2_error (sb, "ext2_free_inode",
"bit already cleared for inode %lu", ino);
else {
desc = ext2_get_group_desc (sb, block_group, &bh2);
if (desc) {
desc->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) + 1);
if (is_directory)
desc->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) - 1);
}
mark_buffer_dirty(bh2);
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) + 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh);
}
mark_buffer_dirty(bh);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
sb->s_dirt = 1;
error_return:
unlock_super (sb);
}
/*
* There are two policies for allocating an inode. If the new inode is
* a directory, then a forward search is made for a block group with both
* free space and a low directory-to-inode ratio; if that fails, then of
* the groups with above-average free space, that group with the fewest
* directories already is chosen.
*
* For other inodes, search forward from the parent directory\'s block
* group to find a free inode.
*/
struct inode * ext2_new_inode (const struct inode * dir, int mode, int * err)
{
struct super_block * sb;
struct buffer_head * bh;
struct buffer_head * bh2;
int i, j, avefreei;
struct inode * inode;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_group_desc * tmp;
struct ext2_super_block * es;
/* Cannot create files in a deleted directory */
if (!dir || !dir->i_nlink) {
*err = -EPERM;
return NULL;
}
inode = get_empty_inode ();
if (!inode) {
*err = -ENOMEM;
return NULL;
}
sb = dir->i_sb;
inode->i_sb = sb;
inode->i_flags = 0;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
repeat:
gdp = NULL; i=0;
*err = -ENOSPC;
if (S_ISDIR(mode)) {
avefreei = le32_to_cpu(es->s_free_inodes_count) /
sb->u.ext2_sb.s_groups_count;
/* I am not yet convinced that this next bit is necessary.
i = dir->u.ext2_i.i_block_group;
for (j = 0; j < sb->u.ext2_sb.s_groups_count; j++) {
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp &&
(le16_to_cpu(tmp->bg_used_dirs_count) << 8) <
le16_to_cpu(tmp->bg_free_inodes_count)) {
gdp = tmp;
break;
}
else
i = ++i % sb->u.ext2_sb.s_groups_count;
}
*/
if (!gdp) {
for (j = 0; j < sb->u.ext2_sb.s_groups_count; j++) {
tmp = ext2_get_group_desc (sb, j, &bh2);
if (tmp &&
le16_to_cpu(tmp->bg_free_inodes_count) &&
le16_to_cpu(tmp->bg_free_inodes_count) >= avefreei) {
if (!gdp ||
(le16_to_cpu(tmp->bg_free_blocks_count) >
le16_to_cpu(gdp->bg_free_blocks_count))) {
i = j;
gdp = tmp;
}
}
}
}
}
else
{
/*
* Try to place the inode in its parent directory
*/
i = dir->u.ext2_i.i_block_group;
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp && le16_to_cpu(tmp->bg_free_inodes_count))
gdp = tmp;
else
{
/*
* Use a quadratic hash to find a group with a
* free inode
*/
for (j = 1; j < sb->u.ext2_sb.s_groups_count; j <<= 1) {
i += j;
if (i >= sb->u.ext2_sb.s_groups_count)
i -= sb->u.ext2_sb.s_groups_count;
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp &&
le16_to_cpu(tmp->bg_free_inodes_count)) {
gdp = tmp;
break;
}
}
}
if (!gdp) {
/*
* That failed: try linear search for a free inode
*/
i = dir->u.ext2_i.i_block_group + 1;
for (j = 2; j < sb->u.ext2_sb.s_groups_count; j++) {
if (++i >= sb->u.ext2_sb.s_groups_count)
i = 0;
tmp = ext2_get_group_desc (sb, i, &bh2);
if (tmp &&
le16_to_cpu(tmp->bg_free_inodes_count)) {
gdp = tmp;
break;
}
}
}
}
if (!gdp) {
unlock_super (sb);
iput(inode);
return NULL;
}
bitmap_nr = load_inode_bitmap (sb, i);
if (bitmap_nr < 0) {
unlock_super (sb);
iput(inode);
*err = -EIO;
return NULL;
}
bh = sb->u.ext2_sb.s_inode_bitmap[bitmap_nr];
if ((j = ext2_find_first_zero_bit ((unsigned long *) bh->b_data,
EXT2_INODES_PER_GROUP(sb))) <
EXT2_INODES_PER_GROUP(sb)) {
if (ext2_set_bit (j, bh->b_data)) {
ext2_warning (sb, "ext2_new_inode",
"bit already set for inode %d", j);
goto repeat;
}
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
} else {
if (le16_to_cpu(gdp->bg_free_inodes_count) != 0) {
ext2_error (sb, "ext2_new_inode",
"Free inodes count corrupted in group %d",
i);
unlock_super (sb);
iput (inode);
return NULL;
}
goto repeat;
}
j += i * EXT2_INODES_PER_GROUP(sb) + 1;
if (j < EXT2_FIRST_INO(sb) || j > le32_to_cpu(es->s_inodes_count)) {
ext2_error (sb, "ext2_new_inode",
"reserved inode or inode > inodes count - "
"block_group = %d,inode=%d", i, j);
unlock_super (sb);
iput (inode);
return NULL;
}
gdp->bg_free_inodes_count =
cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) - 1);
if (S_ISDIR(mode))
gdp->bg_used_dirs_count =
cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) + 1);
mark_buffer_dirty(bh2, 1);
es->s_free_inodes_count =
cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) - 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
inode->i_mode = mode;
inode->i_sb = sb;
inode->i_nlink = 1;
inode->i_dev = sb->s_dev;
inode->i_uid = current->fsuid;
if (test_opt (sb, GRPID))
inode->i_gid = dir->i_gid;
else if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
mode |= S_ISGID;
} else
inode->i_gid = current->fsgid;
inode->i_ino = j;
inode->i_blksize = PAGE_SIZE; /* This is the optimal IO size (for stat), not the fs block size */
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->u.ext2_i.i_new_inode = 1;
inode->u.ext2_i.i_flags = dir->u.ext2_i.i_flags;
if (S_ISLNK(mode))
inode->u.ext2_i.i_flags &= ~(EXT2_IMMUTABLE_FL | EXT2_APPEND_FL);
inode->u.ext2_i.i_faddr = 0;
inode->u.ext2_i.i_frag_no = 0;
inode->u.ext2_i.i_frag_size = 0;
inode->u.ext2_i.i_file_acl = 0;
inode->u.ext2_i.i_dir_acl = 0;
inode->u.ext2_i.i_dtime = 0;
inode->u.ext2_i.i_block_group = i;
inode->i_op = NULL;
if (inode->u.ext2_i.i_flags & EXT2_SYNC_FL)
inode->i_flags |= MS_SYNCHRONOUS;
insert_inode_hash(inode);
mark_inode_dirty(inode);
inc_inode_version (inode, gdp, mode);
unlock_super (sb);
if(DQUOT_ALLOC_INODE(sb, inode)) {
sb->dq_op->drop(inode);
inode->i_nlink = 0;
iput(inode);
*err = -EDQUOT;
return NULL;
}
ext2_debug ("allocating inode %lu\n", inode->i_ino);
*err = 0;
return inode;
}
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;
}
/*
* There are two policies for allocating an inode. If the new inode is
* a directory, then a forward search is made for a block group with both
* free space and a low directory-to-inode ratio; if that fails, then of
* the groups with above-average free space, that group with the fewest
* directories already is chosen.
*
* For other inodes, search forward from the parent directory\'s block
* group to find a free inode.
*/
ino_t
ext2_alloc_inode (ino_t dir_inum, mode_t mode)
{
char *bh = NULL;
int i, j, avefreei;
ino_t inum;
struct ext2_group_desc *gdp;
struct ext2_group_desc *tmp;
pthread_spin_lock (&global_lock);
repeat:
assert (bh == NULL);
gdp = NULL;
i = 0;
if (S_ISDIR (mode))
{
avefreei = sblock->s_free_inodes_count / groups_count;
/* I am not yet convinced that this next bit is necessary.
i = inode_group_num(dir_inum);
for (j = 0; j < groups_count; j++)
{
tmp = group_desc (i);
if ((tmp->bg_used_dirs_count << 8) < tmp->bg_free_inodes_count)
{
gdp = tmp;
break;
}
else
i = ++i % groups_count;
}
*/
if (!gdp)
{
for (j = 0; j < groups_count; j++)
{
tmp = group_desc (j);
if (tmp->bg_free_inodes_count
&& tmp->bg_free_inodes_count >= avefreei)
{
if (!gdp ||
(tmp->bg_free_blocks_count > gdp->bg_free_blocks_count))
{
i = j;
gdp = tmp;
}
}
}
}
}
else
{
/*
* Try to place the inode in its parent directory
*/
i = inode_group_num(dir_inum);
tmp = group_desc (i);
if (tmp->bg_free_inodes_count)
gdp = tmp;
else
{
/*
* Use a quadratic hash to find a group with a
* free inode
*/
for (j = 1; j < groups_count; j <<= 1)
{
i += j;
if (i >= groups_count)
i -= groups_count;
tmp = group_desc (i);
if (tmp->bg_free_inodes_count)
{
gdp = tmp;
break;
}
}
}
if (!gdp)
{
/*
* That failed: try linear search for a free inode
*/
i = inode_group_num(dir_inum) + 1;
for (j = 2; j < groups_count; j++)
{
if (++i >= groups_count)
i = 0;
tmp = group_desc (i);
if (tmp->bg_free_inodes_count)
{
gdp = tmp;
break;
}
}
}
}
if (!gdp)
{
pthread_spin_unlock (&global_lock);
return 0;
}
bh = disk_cache_block_ref (gdp->bg_inode_bitmap);
if ((inum =
find_first_zero_bit ((unsigned long *) bh, sblock->s_inodes_per_group))
< sblock->s_inodes_per_group)
{
if (set_bit (inum, bh))
{
ext2_warning ("bit already set for inode %d", inum);
disk_cache_block_deref (bh);
bh = NULL;
goto repeat;
}
record_global_poke (bh);
bh = NULL;
}
else
{
disk_cache_block_deref (bh);
bh = NULL;
if (gdp->bg_free_inodes_count != 0)
{
ext2_error ("free inodes count corrupted in group %d", i);
inum = 0;
goto sync_out;
}
goto repeat;
}
inum += i * sblock->s_inodes_per_group + 1;
if (inum < EXT2_FIRST_INO (sblock) || inum > sblock->s_inodes_count)
{
ext2_error ("reserved inode or inode > inodes count - "
"block_group = %d,inode=%d", i, inum);
inum = 0;
goto sync_out;
}
gdp->bg_free_inodes_count--;
if (S_ISDIR (mode))
gdp->bg_used_dirs_count++;
disk_cache_block_ref_ptr (gdp);
record_global_poke (gdp);
sblock->s_free_inodes_count--;
sblock_dirty = 1;
sync_out:
assert (bh == NULL);
pthread_spin_unlock (&global_lock);
alloc_sync (0);
/* Make sure the coming read_node won't complain about bad
fields. */
{
struct ext2_inode *di = dino_ref (inum);
memset (di, 0, sizeof *di);
dino_deref (di);
}
return inum;
}