int ext4_ext_migrate(struct inode *inode)
{
handle_t *handle;
int retval = 0, i;
__le32 *i_data;
ext4_lblk_t blk_count = 0;
struct ext4_inode_info *ei;
struct inode *tmp_inode = NULL;
struct list_blocks_struct lb;
unsigned long max_entries;
__u32 goal;
/*
* If the filesystem does not support extents, or the inode
* already is extent-based, error out.
*/
if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
EXT4_FEATURE_INCOMPAT_EXTENTS) ||
(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
return -EINVAL;
if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
/*
* don't migrate fast symlink
*/
return retval;
handle = ext4_journal_start(inode,
EXT4_DATA_TRANS_BLOCKS(inode->i_sb) +
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)
+ 1);
if (IS_ERR(handle)) {
retval = PTR_ERR(handle);
return retval;
}
goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
S_IFREG, 0, goal);
if (IS_ERR(tmp_inode)) {
retval = -ENOMEM;
ext4_journal_stop(handle);
return retval;
}
i_size_write(tmp_inode, i_size_read(inode));
/*
* We don't want the inode to be reclaimed
* if we got interrupted in between. We have
* this tmp inode carrying reference to the
* data blocks of the original file. We set
* the i_nlink to zero at the last stage after
* switching the original file to extent format
*/
tmp_inode->i_nlink = 1;
ext4_ext_tree_init(handle, tmp_inode);
ext4_orphan_add(handle, tmp_inode);
ext4_journal_stop(handle);
/*
* start with one credit accounted for
* superblock modification.
*
* For the tmp_inode we already have commited the
* trascation that created the inode. Later as and
* when we add extents we extent the journal
*/
/*
* Even though we take i_mutex we can still cause block
* allocation via mmap write to holes. If we have allocated
* new blocks we fail migrate. New block allocation will
* clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
* with i_data_sem held to prevent racing with block
* allocation.
*/
down_read((&EXT4_I(inode)->i_data_sem));
EXT4_I(inode)->i_state |= EXT4_STATE_EXT_MIGRATE;
up_read((&EXT4_I(inode)->i_data_sem));
handle = ext4_journal_start(inode, 1);
ei = EXT4_I(inode);
i_data = ei->i_data;
memset(&lb, 0, sizeof(lb));
/* 32 bit block address 4 bytes */
max_entries = inode->i_sb->s_blocksize >> 2;
for (i = 0; i < EXT4_NDIR_BLOCKS; i++, blk_count++) {
if (i_data[i]) {
retval = update_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[i]),
blk_count, &lb);
if (retval)
goto err_out;
}
}
if (i_data[EXT4_IND_BLOCK]) {
retval = update_ind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_IND_BLOCK]),
&blk_count, &lb);
if (retval)
goto err_out;
} else
blk_count += max_entries;
if (i_data[EXT4_DIND_BLOCK]) {
retval = update_dind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_DIND_BLOCK]),
&blk_count, &lb);
if (retval)
goto err_out;
} else
blk_count += max_entries * max_entries;
if (i_data[EXT4_TIND_BLOCK]) {
retval = update_tind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_TIND_BLOCK]),
&blk_count, &lb);
if (retval)
goto err_out;
}
/*
* Build the last extent
*/
retval = finish_range(handle, tmp_inode, &lb);
err_out:
if (retval)
/*
* Failure case delete the extent information with the
* tmp_inode
*/
free_ext_block(handle, tmp_inode);
else {
retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
if (retval)
/*
* if we fail to swap inode data free the extent
* details of the tmp inode
*/
free_ext_block(handle, tmp_inode);
}
/* We mark the tmp_inode dirty via ext4_ext_tree_init. */
if (ext4_journal_extend(handle, 1) != 0)
ext4_journal_restart(handle, 1);
/*
* Mark the tmp_inode as of size zero
*/
i_size_write(tmp_inode, 0);
/*
* set the i_blocks count to zero
* so that the ext4_delete_inode does the
* right job
*
* We don't need to take the i_lock because
* the inode is not visible to user space.
*/
tmp_inode->i_blocks = 0;
/* Reset the extent details */
ext4_ext_tree_init(handle, tmp_inode);
/*
* Set the i_nlink to zero so that
* generic_drop_inode really deletes the
* inode
*/
tmp_inode->i_nlink = 0;
ext4_journal_stop(handle);
unlock_new_inode(tmp_inode);
iput(tmp_inode);
return retval;
}
int ext4_ext_migrate(struct inode *inode)
{
handle_t *handle;
int retval = 0, i;
__le32 *i_data;
struct ext4_inode_info *ei;
struct inode *tmp_inode = NULL;
struct migrate_struct lb;
unsigned long max_entries;
__u32 goal;
uid_t owner[2];
/*
* If the filesystem does not support extents, or the inode
* already is extent-based, error out.
*/
if (!EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
EXT4_FEATURE_INCOMPAT_EXTENTS) ||
(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
return -EINVAL;
if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
/*
* don't migrate fast symlink
*/
return retval;
/*
* Worst case we can touch the allocation bitmaps, a bgd
* block, and a block to link in the orphan list. We do need
* need to worry about credits for modifying the quota inode.
*/
handle = ext4_journal_start(inode, EXT4_HT_MIGRATE,
4 + EXT4_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb));
if (IS_ERR(handle)) {
retval = PTR_ERR(handle);
return retval;
}
goal = (((inode->i_ino - 1) / EXT4_INODES_PER_GROUP(inode->i_sb)) *
EXT4_INODES_PER_GROUP(inode->i_sb)) + 1;
owner[0] = i_uid_read(inode);
owner[1] = i_gid_read(inode);
tmp_inode = ext4_new_inode(handle, inode->i_sb->s_root->d_inode,
S_IFREG, NULL, goal, owner);
if (IS_ERR(tmp_inode)) {
retval = PTR_ERR(tmp_inode);
ext4_journal_stop(handle);
return retval;
}
i_size_write(tmp_inode, i_size_read(inode));
/*
* Set the i_nlink to zero so it will be deleted later
* when we drop inode reference.
*/
clear_nlink(tmp_inode);
ext4_ext_tree_init(handle, tmp_inode);
ext4_orphan_add(handle, tmp_inode);
ext4_journal_stop(handle);
/*
* start with one credit accounted for
* superblock modification.
*
* For the tmp_inode we already have committed the
* trascation that created the inode. Later as and
* when we add extents we extent the journal
*/
/*
* Even though we take i_mutex we can still cause block
* allocation via mmap write to holes. If we have allocated
* new blocks we fail migrate. New block allocation will
* clear EXT4_STATE_EXT_MIGRATE flag. The flag is updated
* with i_data_sem held to prevent racing with block
* allocation.
*/
down_read((&EXT4_I(inode)->i_data_sem));
ext4_set_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
up_read((&EXT4_I(inode)->i_data_sem));
handle = ext4_journal_start(inode, EXT4_HT_MIGRATE, 1);
if (IS_ERR(handle)) {
/*
* It is impossible to update on-disk structures without
* a handle, so just rollback in-core changes and live other
* work to orphan_list_cleanup()
*/
ext4_orphan_del(NULL, tmp_inode);
retval = PTR_ERR(handle);
goto out;
}
ei = EXT4_I(inode);
i_data = ei->i_data;
memset(&lb, 0, sizeof(lb));
/* 32 bit block address 4 bytes */
max_entries = inode->i_sb->s_blocksize >> 2;
for (i = 0; i < EXT4_NDIR_BLOCKS; i++) {
if (i_data[i]) {
retval = update_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[i]), &lb);
if (retval)
goto err_out;
} else
lb.curr_block++;
}
if (i_data[EXT4_IND_BLOCK]) {
retval = update_ind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_IND_BLOCK]), &lb);
if (retval)
goto err_out;
} else
lb.curr_block += max_entries;
if (i_data[EXT4_DIND_BLOCK]) {
retval = update_dind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_DIND_BLOCK]), &lb);
if (retval)
goto err_out;
} else
lb.curr_block += max_entries * max_entries;
if (i_data[EXT4_TIND_BLOCK]) {
retval = update_tind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_TIND_BLOCK]), &lb);
if (retval)
goto err_out;
}
/*
* Build the last extent
*/
retval = finish_range(handle, tmp_inode, &lb);
err_out:
if (retval)
/*
* Failure case delete the extent information with the
* tmp_inode
*/
free_ext_block(handle, tmp_inode);
else {
retval = ext4_ext_swap_inode_data(handle, inode, tmp_inode);
if (retval)
/*
* if we fail to swap inode data free the extent
* details of the tmp inode
*/
free_ext_block(handle, tmp_inode);
}
/* We mark the tmp_inode dirty via ext4_ext_tree_init. */
if (ext4_journal_extend(handle, 1) != 0)
ext4_journal_restart(handle, 1);
/*
* Mark the tmp_inode as of size zero
*/
i_size_write(tmp_inode, 0);
/*
* set the i_blocks count to zero
* so that the ext4_delete_inode does the
* right job
*
* We don't need to take the i_lock because
* the inode is not visible to user space.
*/
tmp_inode->i_blocks = 0;
/* Reset the extent details */
ext4_ext_tree_init(handle, tmp_inode);
ext4_journal_stop(handle);
out:
unlock_new_inode(tmp_inode);
iput(tmp_inode);
return retval;
}
int ext4_ext_migrate(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
handle_t *handle;
int retval = 0, i;
__le32 *i_data;
ext4_lblk_t blk_count = 0;
struct ext4_inode_info *ei;
struct inode *tmp_inode = NULL;
struct list_blocks_struct lb;
unsigned long max_entries;
if (!test_opt(inode->i_sb, EXTENTS))
/*
* if mounted with noextents we don't allow the migrate
*/
return -EINVAL;
if ((EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL))
return -EINVAL;
if (S_ISLNK(inode->i_mode) && inode->i_blocks == 0)
/*
* don't migrate fast symlink
*/
return retval;
handle = ext4_journal_start(inode,
EXT4_DATA_TRANS_BLOCKS(inode->i_sb) +
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
2 * EXT4_QUOTA_INIT_BLOCKS(inode->i_sb)
+ 1);
if (IS_ERR(handle)) {
retval = PTR_ERR(handle);
goto err_out;
}
tmp_inode = ext4_new_inode(handle,
inode->i_sb->s_root->d_inode,
S_IFREG);
if (IS_ERR(tmp_inode)) {
retval = -ENOMEM;
ext4_journal_stop(handle);
tmp_inode = NULL;
goto err_out;
}
i_size_write(tmp_inode, i_size_read(inode));
/*
* We don't want the inode to be reclaimed
* if we got interrupted in between. We have
* this tmp inode carrying reference to the
* data blocks of the original file. We set
* the i_nlink to zero at the last stage after
* switching the original file to extent format
*/
tmp_inode->i_nlink = 1;
ext4_ext_tree_init(handle, tmp_inode);
ext4_orphan_add(handle, tmp_inode);
ext4_journal_stop(handle);
/*
* start with one credit accounted for
* superblock modification.
*
* For the tmp_inode we already have commited the
* trascation that created the inode. Later as and
* when we add extents we extent the journal
*/
/*
* inode_mutex prevent write and truncate on the file. Read still goes
* through. We take i_data_sem in ext4_ext_swap_inode_data before we
* switch the inode format to prevent read.
*/
mutex_lock(&(inode->i_mutex));
handle = ext4_journal_start(inode, 1);
ei = EXT4_I(inode);
i_data = ei->i_data;
memset(&lb, 0, sizeof(lb));
/* 32 bit block address 4 bytes */
max_entries = inode->i_sb->s_blocksize >> 2;
for (i = 0; i < EXT4_NDIR_BLOCKS; i++, blk_count++) {
if (i_data[i]) {
retval = update_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[i]),
blk_count, &lb);
if (retval)
goto err_out;
}
}
if (i_data[EXT4_IND_BLOCK]) {
retval = update_ind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_IND_BLOCK]),
&blk_count, &lb);
if (retval)
goto err_out;
} else
blk_count += max_entries;
if (i_data[EXT4_DIND_BLOCK]) {
retval = update_dind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_DIND_BLOCK]),
&blk_count, &lb);
if (retval)
goto err_out;
} else
blk_count += max_entries * max_entries;
if (i_data[EXT4_TIND_BLOCK]) {
retval = update_tind_extent_range(handle, tmp_inode,
le32_to_cpu(i_data[EXT4_TIND_BLOCK]),
&blk_count, &lb);
if (retval)
goto err_out;
}
/*
* Build the last extent
*/
retval = finish_range(handle, tmp_inode, &lb);
err_out:
if (retval)
/*
* Failure case delete the extent information with the
* tmp_inode
*/
free_ext_block(handle, tmp_inode);
else
retval = ext4_ext_swap_inode_data(handle, inode,
tmp_inode);
/* We mark the tmp_inode dirty via ext4_ext_tree_init. */
if (ext4_journal_extend(handle, 1) != 0)
ext4_journal_restart(handle, 1);
/*
* Mark the tmp_inode as of size zero
*/
i_size_write(tmp_inode, 0);
/*
* set the i_blocks count to zero
* so that the ext4_delete_inode does the
* right job
*
* We don't need to take the i_lock because
* the inode is not visible to user space.
*/
tmp_inode->i_blocks = 0;
/* Reset the extent details */
ext4_ext_tree_init(handle, tmp_inode);
/*
* Set the i_nlink to zero so that
* generic_drop_inode really deletes the
* inode
*/
tmp_inode->i_nlink = 0;
ext4_journal_stop(handle);
mutex_unlock(&(inode->i_mutex));
if (tmp_inode)
iput(tmp_inode);
return retval;
}