/**
* dbg_check_old_index - check the old copy of the index.
* @c: UBIFS file-system description object
* @zroot: root of the new index
*
* In order to be able to recover from an unclean unmount, a complete copy of
* the index must exist on flash. This is the "old" index. The commit process
* must write the "new" index to flash without overwriting or destroying any
* part of the old index. This function is run at commit end in order to check
* that the old index does indeed exist completely intact.
*
* This function returns %0 on success and a negative error code on failure.
*/
int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot)
{
int lnum, offs, len, err = 0, uninitialized_var(last_level), child_cnt;
int first = 1, iip;
struct ubifs_debug_info *d = c->dbg;
union ubifs_key lower_key, upper_key, l_key, u_key;
unsigned long long uninitialized_var(last_sqnum);
struct ubifs_idx_node *idx;
struct list_head list;
struct idx_node *i;
size_t sz;
if (!(ubifs_chk_flags & UBIFS_CHK_OLD_IDX))
goto out;
INIT_LIST_HEAD(&list);
sz = sizeof(struct idx_node) + ubifs_idx_node_sz(c, c->fanout) -
UBIFS_IDX_NODE_SZ;
/* Start at the old zroot */
lnum = d->old_zroot.lnum;
offs = d->old_zroot.offs;
len = d->old_zroot.len;
iip = 0;
/*
* Traverse the index tree preorder depth-first i.e. do a node and then
* its subtrees from left to right.
*/
while (1) {
struct ubifs_branch *br;
/* Get the next index node */
i = kmalloc(sz, GFP_NOFS);
if (!i) {
err = -ENOMEM;
goto out_free;
}
i->iip = iip;
/* Keep the index nodes on our path in a linked list */
list_add_tail(&i->list, &list);
/* Read the index node */
idx = &i->idx;
err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs);
if (err)
goto out_free;
/* Validate index node */
child_cnt = le16_to_cpu(idx->child_cnt);
if (child_cnt < 1 || child_cnt > c->fanout) {
err = 1;
goto out_dump;
}
if (first) {
first = 0;
/* Check root level and sqnum */
if (le16_to_cpu(idx->level) != d->old_zroot_level) {
err = 2;
goto out_dump;
}
if (le64_to_cpu(idx->ch.sqnum) != d->old_zroot_sqnum) {
err = 3;
goto out_dump;
}
/* Set last values as though root had a parent */
last_level = le16_to_cpu(idx->level) + 1;
last_sqnum = le64_to_cpu(idx->ch.sqnum) + 1;
key_read(c, ubifs_idx_key(c, idx), &lower_key);
highest_ino_key(c, &upper_key, INUM_WATERMARK);
}
key_copy(c, &upper_key, &i->upper_key);
if (le16_to_cpu(idx->level) != last_level - 1) {
err = 3;
goto out_dump;
}
/*
* The index is always written bottom up hence a child's sqnum
* is always less than the parents.
*/
if (le64_to_cpu(idx->ch.sqnum) >= last_sqnum) {
err = 4;
goto out_dump;
}
/* Check key range */
key_read(c, ubifs_idx_key(c, idx), &l_key);
br = ubifs_idx_branch(c, idx, child_cnt - 1);
key_read(c, &br->key, &u_key);
if (keys_cmp(c, &lower_key, &l_key) > 0) {
err = 5;
goto out_dump;
}
if (keys_cmp(c, &upper_key, &u_key) < 0) {
err = 6;
goto out_dump;
}
if (keys_cmp(c, &upper_key, &u_key) == 0)
if (!is_hash_key(c, &u_key)) {
err = 7;
goto out_dump;
}
/* Go to next index node */
if (le16_to_cpu(idx->level) == 0) {
/* At the bottom, so go up until can go right */
while (1) {
/* Drop the bottom of the list */
list_del(&i->list);
kfree(i);
/* No more list means we are done */
if (list_empty(&list))
goto out;
/* Look at the new bottom */
i = list_entry(list.prev, struct idx_node,
list);
idx = &i->idx;
/* Can we go right */
if (iip + 1 < le16_to_cpu(idx->child_cnt)) {
iip = iip + 1;
break;
} else
/* Nope, so go up again */
iip = i->iip;
}
} else
/* Go down left */
iip = 0;
/*
* We have the parent in 'idx' and now we set up for reading the
* child pointed to by slot 'iip'.
*/
last_level = le16_to_cpu(idx->level);
last_sqnum = le64_to_cpu(idx->ch.sqnum);
br = ubifs_idx_branch(c, idx, iip);
lnum = le32_to_cpu(br->lnum);
offs = le32_to_cpu(br->offs);
len = le32_to_cpu(br->len);
key_read(c, &br->key, &lower_key);
if (iip + 1 < le16_to_cpu(idx->child_cnt)) {
br = ubifs_idx_branch(c, idx, iip + 1);
key_read(c, &br->key, &upper_key);
} else
key_copy(c, &i->upper_key, &upper_key);
}
int ubifs_jrn_delete_xattr(struct ubifs_info *c, const struct inode *host,
const struct inode *inode, const struct qstr *nm,
int sync)
{
int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
struct ubifs_dent_node *xent;
struct ubifs_ino_node *ino;
union ubifs_key xent_key, key1, key2;
dbg_jrn("host %lu, xattr ino %lu, name '%s', data len %d",
host->i_ino, inode->i_ino, nm->name,
ubifs_inode(inode)->data_len);
ubifs_assert(inode->i_nlink == 0);
/*
* Since we are deleting the inode, we do not bother to attach any data
* to it and assume its length is %UBIFS_INO_NODE_SZ.
*/
xlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
aligned_xlen = ALIGN(xlen, 8);
hlen = ubifs_inode(host)->data_len + UBIFS_INO_NODE_SZ;
len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
xent = kmalloc(len, GFP_NOFS);
if (!xent)
return -ENOMEM;
xent->ch.node_type = UBIFS_XENT_NODE;
xent_key_init(c, &xent_key, host->i_ino, nm);
key_write(c, &xent_key, xent->key);
xent->inum = 0;
xent->type = get_dent_type(inode->i_mode);
xent->nlen = cpu_to_le16(nm->len);
memcpy(xent->name, nm->name, nm->len);
xent->name[nm->len] = '\0';
zero_dent_node_unused(xent);
ubifs_prep_grp_node(c, xent, xlen, 0);
ino = (void *)xent + aligned_xlen;
pack_inode(c, ino, inode, 0, 1);
ino = (void *)ino + UBIFS_INO_NODE_SZ;
pack_inode(c, ino, host, 1, 0);
err = make_reservation(c, BASEHD, len);
if (err) {
kfree(xent);
return err;
}
err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
if (!sync && !err)
ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
release_head(c, BASEHD);
kfree(xent);
if (err)
goto out_ro;
/* Remove the extended attribute entry from TNC */
err = ubifs_tnc_remove_nm(c, &xent_key, nm);
if (err)
goto out_ro;
err = ubifs_add_dirt(c, lnum, xlen);
if (err)
goto out_ro;
/*
* Remove all nodes belonging to the extended attribute inode from TNC.
* Well, there actually must be only one node - the inode itself.
*/
lowest_ino_key(c, &key1, inode->i_ino);
highest_ino_key(c, &key2, inode->i_ino);
err = ubifs_tnc_remove_range(c, &key1, &key2);
if (err)
goto out_ro;
err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
if (err)
goto out_ro;
/* And update TNC with the new host inode position */
ino_key_init(c, &key1, host->i_ino);
err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
if (err)
goto out_ro;
finish_reservation(c);
return 0;
out_ro:
ubifs_ro_mode(c, err);
finish_reservation(c);
return err;
}
