u64 ovl_dentry_version_get(struct dentry *dentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
WARN_ON(!inode_is_locked(dentry->d_inode));
return oe->version;
}
void ovl_dentry_version_inc(struct dentry *dentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
WARN_ON(!inode_is_locked(dentry->d_inode));
oe->version++;
}
/*
* Prevent concurrent writepages on inode
*
* This is done by adding a negative bias to the inode write counter
* and waiting for all pending writes to finish.
*/
void fuse_set_nowrite(struct inode *inode)
{
struct fuse_inode *fi = get_fuse_inode(inode);
BUG_ON(!inode_is_locked(inode));
spin_lock(&fi->lock);
BUG_ON(fi->writectr < 0);
fi->writectr += FUSE_NOWRITE;
spin_unlock(&fi->lock);
wait_event(fi->page_waitq, fi->writectr == FUSE_NOWRITE);
}
/*
* We use I_MUTEX_CHILD here to silence lockdep. It's safe because xattr
* mutation ops aren't called during rename or splace, which are the
* only other users of I_MUTEX_CHILD. It violates the ordering, but that's
* better than allocating another subclass just for this code.
*/
static int xattr_unlink(struct inode *dir, struct dentry *dentry)
{
int error;
BUG_ON(!inode_is_locked(dir));
inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD);
error = dir->i_op->unlink(dir, dentry);
inode_unlock(d_inode(dentry));
if (!error)
d_delete(dentry);
return error;
}
void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
WARN_ON(!inode_is_locked(upperdentry->d_parent->d_inode));
WARN_ON(oe->__upperdentry);
BUG_ON(!upperdentry->d_inode);
/*
* Make sure upperdentry is consistent before making it visible to
* ovl_upperdentry_dereference().
*/
smp_wmb();
oe->__upperdentry = upperdentry;
}
/*******************************************************************************
fs_iget: returns a locked previously allocated inode
*******************************************************************************/
struct inode * fs_iget(dev_nr_t dev_nr, inode_nr_t inode_nr)
{
struct inode *ip;
assert(dev_nr, "fs_iget(): dev_nr == 0");
repeat:
if ( (ip = ihash_table_get_inode(dev_nr, inode_nr)) ) {
if (inode_is_locked(ip)) {
;// sleep on this inode
goto repeat;
}
if (!inode_get_count(ip)) /* the inode is on the free list */
ifree_list_remove_inode(ip);
inode_lock(ip);
inode_count_inc(ip);
// especial processing for mount points ......
// ...................
return ip;
}
/* the inode was not in memory */
if (ifree_list_is_empty())
return NULL;
ip = ifree_list_get_head();
ifree_list_remove_inode(ip);
if (inode_is_valid(ip)) /* the inode is on the hash table */
ihash_table_remove_inode(ip);
inode_set_dev_nr(ip, dev_nr);
inode_set_nr(ip, inode_nr);
ihash_table_insert_inode(ip);
inode_lock(ip);
inode_count_inc(ip);
fs_iread(ip);
return ip;
}
static int do_setxattr(struct btrfs_trans_handle *trans,
struct inode *inode, const char *name,
const void *value, size_t size, int flags)
{
struct btrfs_dir_item *di = NULL;
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_path *path;
size_t name_len = strlen(name);
int ret = 0;
if (name_len + size > BTRFS_MAX_XATTR_SIZE(root))
return -ENOSPC;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->skip_release_on_error = 1;
if (!value) {
di = btrfs_lookup_xattr(trans, root, path, btrfs_ino(inode),
name, name_len, -1);
if (!di && (flags & XATTR_REPLACE))
ret = -ENODATA;
else if (IS_ERR(di))
ret = PTR_ERR(di);
else if (di)
ret = btrfs_delete_one_dir_name(trans, root, path, di);
goto out;
}
/*
* For a replace we can't just do the insert blindly.
* Do a lookup first (read-only btrfs_search_slot), and return if xattr
* doesn't exist. If it exists, fall down below to the insert/replace
* path - we can't race with a concurrent xattr delete, because the VFS
* locks the inode's i_mutex before calling setxattr or removexattr.
*/
if (flags & XATTR_REPLACE) {
ASSERT(inode_is_locked(inode));
di = btrfs_lookup_xattr(NULL, root, path, btrfs_ino(inode),
name, name_len, 0);
if (!di)
ret = -ENODATA;
else if (IS_ERR(di))
ret = PTR_ERR(di);
if (ret)
goto out;
btrfs_release_path(path);
di = NULL;
}
ret = btrfs_insert_xattr_item(trans, root, path, btrfs_ino(inode),
name, name_len, value, size);
if (ret == -EOVERFLOW) {
/*
* We have an existing item in a leaf, split_leaf couldn't
* expand it. That item might have or not a dir_item that
* matches our target xattr, so lets check.
*/
ret = 0;
btrfs_assert_tree_locked(path->nodes[0]);
di = btrfs_match_dir_item_name(root, path, name, name_len);
if (!di && !(flags & XATTR_REPLACE)) {
ret = -ENOSPC;
goto out;
}
} else if (ret == -EEXIST) {
ret = 0;
di = btrfs_match_dir_item_name(root, path, name, name_len);
ASSERT(di); /* logic error */
} else if (ret) {
goto out;
}
if (di && (flags & XATTR_CREATE)) {
ret = -EEXIST;
goto out;
}
if (di) {
/*
* We're doing a replace, and it must be atomic, that is, at
* any point in time we have either the old or the new xattr
* value in the tree. We don't want readers (getxattr and
* listxattrs) to miss a value, this is specially important
* for ACLs.
*/
const int slot = path->slots[0];
struct extent_buffer *leaf = path->nodes[0];
const u16 old_data_len = btrfs_dir_data_len(leaf, di);
const u32 item_size = btrfs_item_size_nr(leaf, slot);
const u32 data_size = sizeof(*di) + name_len + size;
struct btrfs_item *item;
unsigned long data_ptr;
char *ptr;
if (size > old_data_len) {
if (btrfs_leaf_free_space(root, leaf) <
(size - old_data_len)) {
ret = -ENOSPC;
goto out;
}
}
if (old_data_len + name_len + sizeof(*di) == item_size) {
/* No other xattrs packed in the same leaf item. */
if (size > old_data_len)
btrfs_extend_item(root, path,
size - old_data_len);
else if (size < old_data_len)
btrfs_truncate_item(root, path, data_size, 1);
} else {
/* There are other xattrs packed in the same item. */
ret = btrfs_delete_one_dir_name(trans, root, path, di);
if (ret)
goto out;
btrfs_extend_item(root, path, data_size);
}
item = btrfs_item_nr(slot);
ptr = btrfs_item_ptr(leaf, slot, char);
ptr += btrfs_item_size(leaf, item) - data_size;
di = (struct btrfs_dir_item *)ptr;
btrfs_set_dir_data_len(leaf, di, size);
data_ptr = ((unsigned long)(di + 1)) + name_len;
write_extent_buffer(leaf, value, data_ptr, size);
btrfs_mark_buffer_dirty(leaf);
} else {
/*
* Insert, and we had space for the xattr, so path->slots[0] is
* where our xattr dir_item is and btrfs_insert_xattr_item()
* filled it.
*/
}
static int xattr_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
BUG_ON(!inode_is_locked(dir));
return dir->i_op->mkdir(dir, dentry, mode);
}
static int xattr_create(struct inode *dir, struct dentry *dentry, int mode)
{
BUG_ON(!inode_is_locked(dir));
return dir->i_op->create(dir, dentry, mode, true);
}
/**
* notify_change - modify attributes of a filesytem object
* @dentry: object affected
* @iattr: new attributes
* @delegated_inode: returns inode, if the inode is delegated
*
* The caller must hold the i_mutex on the affected object.
*
* If notify_change discovers a delegation in need of breaking,
* it will return -EWOULDBLOCK and return a reference to the inode in
* delegated_inode. The caller should then break the delegation and
* retry. Because breaking a delegation may take a long time, the
* caller should drop the i_mutex before doing so.
*
* Alternatively, a caller may pass NULL for delegated_inode. This may
* be appropriate for callers that expect the underlying filesystem not
* to be NFS exported. Also, passing NULL is fine for callers holding
* the file open for write, as there can be no conflicting delegation in
* that case.
*/
int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
{
struct inode *inode = dentry->d_inode;
umode_t mode = inode->i_mode;
int error;
struct timespec now;
unsigned int ia_valid = attr->ia_valid;
WARN_ON_ONCE(!inode_is_locked(inode));
if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_TIMES_SET)) {
if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
return -EPERM;
}
/*
* If utimes(2) and friends are called with times == NULL (or both
* times are UTIME_NOW), then we need to check for write permission
*/
if (ia_valid & ATTR_TOUCH) {
if (IS_IMMUTABLE(inode))
return -EPERM;
if (!inode_owner_or_capable(inode)) {
error = inode_permission(inode, MAY_WRITE);
if (error)
return error;
}
}
if ((ia_valid & ATTR_MODE)) {
umode_t amode = attr->ia_mode;
/* Flag setting protected by i_mutex */
if (is_sxid(amode))
inode->i_flags &= ~S_NOSEC;
}
now = current_fs_time(inode->i_sb);
attr->ia_ctime = now;
if (!(ia_valid & ATTR_ATIME_SET))
attr->ia_atime = now;
if (!(ia_valid & ATTR_MTIME_SET))
attr->ia_mtime = now;
if (ia_valid & ATTR_KILL_PRIV) {
attr->ia_valid &= ~ATTR_KILL_PRIV;
ia_valid &= ~ATTR_KILL_PRIV;
error = security_inode_need_killpriv(dentry);
if (error > 0)
error = security_inode_killpriv(dentry);
if (error)
return error;
}
/*
* We now pass ATTR_KILL_S*ID to the lower level setattr function so
* that the function has the ability to reinterpret a mode change
* that's due to these bits. This adds an implicit restriction that
* no function will ever call notify_change with both ATTR_MODE and
* ATTR_KILL_S*ID set.
*/
if ((ia_valid & (ATTR_KILL_SUID|ATTR_KILL_SGID)) &&
(ia_valid & ATTR_MODE))
BUG();
if (ia_valid & ATTR_KILL_SUID) {
if (mode & S_ISUID) {
ia_valid = attr->ia_valid |= ATTR_MODE;
attr->ia_mode = (inode->i_mode & ~S_ISUID);
}
}
if (ia_valid & ATTR_KILL_SGID) {
if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
if (!(ia_valid & ATTR_MODE)) {
ia_valid = attr->ia_valid |= ATTR_MODE;
attr->ia_mode = inode->i_mode;
}
attr->ia_mode &= ~S_ISGID;
}
}
if (!(attr->ia_valid & ~(ATTR_KILL_SUID | ATTR_KILL_SGID)))
return 0;
/*
* Verify that uid/gid changes are valid in the target
* namespace of the superblock.
*/
if (ia_valid & ATTR_UID &&
!kuid_has_mapping(inode->i_sb->s_user_ns, attr->ia_uid))
return -EOVERFLOW;
if (ia_valid & ATTR_GID &&
!kgid_has_mapping(inode->i_sb->s_user_ns, attr->ia_gid))
return -EOVERFLOW;
/* Don't allow modifications of files with invalid uids or
* gids unless those uids & gids are being made valid.
*/
if (!(ia_valid & ATTR_UID) && !uid_valid(inode->i_uid))
return -EOVERFLOW;
if (!(ia_valid & ATTR_GID) && !gid_valid(inode->i_gid))
return -EOVERFLOW;
error = security_inode_setattr(dentry, attr);
if (error)
return error;
error = try_break_deleg(inode, delegated_inode);
if (error)
return error;
if (inode->i_op->setattr)
error = inode->i_op->setattr(dentry, attr);
else
error = simple_setattr(dentry, attr);
if (!error) {
fsnotify_change(dentry, ia_valid);
ima_inode_post_setattr(dentry);
evm_inode_post_setattr(dentry, ia_valid);
}
return error;
}
static int ubifs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct inode *inode = d_inode(old_dentry);
struct ubifs_inode *ui = ubifs_inode(inode);
struct ubifs_inode *dir_ui = ubifs_inode(dir);
int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
struct ubifs_budget_req req = { .new_dent = 1, .dirtied_ino = 2,
.dirtied_ino_d = ALIGN(ui->data_len, 8) };
/*
* Budget request settings: new direntry, changing the target inode,
* changing the parent inode.
*/
dbg_gen("dent '%pd' to ino %lu (nlink %d) in dir ino %lu",
dentry, inode->i_ino,
inode->i_nlink, dir->i_ino);
ubifs_assert(inode_is_locked(dir));
ubifs_assert(inode_is_locked(inode));
err = dbg_check_synced_i_size(c, inode);
if (err)
return err;
err = ubifs_budget_space(c, &req);
if (err)
return err;
lock_2_inodes(dir, inode);
inc_nlink(inode);
ihold(inode);
inode->i_ctime = ubifs_current_time(inode);
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
if (err)
goto out_cancel;
unlock_2_inodes(dir, inode);
ubifs_release_budget(c, &req);
d_instantiate(dentry, inode);
return 0;
out_cancel:
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
drop_nlink(inode);
unlock_2_inodes(dir, inode);
ubifs_release_budget(c, &req);
iput(inode);
return err;
}
static int ubifs_unlink(struct inode *dir, struct dentry *dentry)
{
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct inode *inode = d_inode(dentry);
struct ubifs_inode *dir_ui = ubifs_inode(dir);
int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
int err, budgeted = 1;
struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
unsigned int saved_nlink = inode->i_nlink;
/*
* Budget request settings: deletion direntry, deletion inode (+1 for
* @dirtied_ino), changing the parent directory inode. If budgeting
* fails, go ahead anyway because we have extra space reserved for
* deletions.
*/
dbg_gen("dent '%pd' from ino %lu (nlink %d) in dir ino %lu",
dentry, inode->i_ino,
inode->i_nlink, dir->i_ino);
ubifs_assert(inode_is_locked(dir));
ubifs_assert(inode_is_locked(inode));
err = dbg_check_synced_i_size(c, inode);
if (err)
return err;
err = ubifs_budget_space(c, &req);
if (err) {
if (err != -ENOSPC)
return err;
budgeted = 0;
}
lock_2_inodes(dir, inode);
inode->i_ctime = ubifs_current_time(dir);
drop_nlink(inode);
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
if (err)
goto out_cancel;
unlock_2_inodes(dir, inode);
if (budgeted)
ubifs_release_budget(c, &req);
else {
/* We've deleted something - clean the "no space" flags */
c->bi.nospace = c->bi.nospace_rp = 0;
smp_wmb();
}
return 0;
out_cancel:
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
set_nlink(inode, saved_nlink);
unlock_2_inodes(dir, inode);
if (budgeted)
ubifs_release_budget(c, &req);
return err;
}
/**
* check_dir_empty - check if a directory is empty or not.
* @c: UBIFS file-system description object
* @dir: VFS inode object of the directory to check
*
* This function checks if directory @dir is empty. Returns zero if the
* directory is empty, %-ENOTEMPTY if it is not, and other negative error codes
* in case of of errors.
*/
static int check_dir_empty(struct ubifs_info *c, struct inode *dir)
{
struct qstr nm = { .name = NULL };
struct ubifs_dent_node *dent;
union ubifs_key key;
int err;
lowest_dent_key(c, &key, dir->i_ino);
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
if (err == -ENOENT)
err = 0;
} else {
kfree(dent);
err = -ENOTEMPTY;
}
return err;
}
static int ubifs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct inode *inode = d_inode(dentry);
int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
int err, budgeted = 1;
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
/*
* Budget request settings: deletion direntry, deletion inode and
* changing the parent inode. If budgeting fails, go ahead anyway
* because we have extra space reserved for deletions.
*/
dbg_gen("directory '%pd', ino %lu in dir ino %lu", dentry,
inode->i_ino, dir->i_ino);
ubifs_assert(inode_is_locked(dir));
ubifs_assert(inode_is_locked(inode));
err = check_dir_empty(c, d_inode(dentry));
if (err)
return err;
err = ubifs_budget_space(c, &req);
if (err) {
if (err != -ENOSPC)
return err;
budgeted = 0;
}
lock_2_inodes(dir, inode);
inode->i_ctime = ubifs_current_time(dir);
clear_nlink(inode);
drop_nlink(dir);
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 1, 0);
if (err)
goto out_cancel;
unlock_2_inodes(dir, inode);
if (budgeted)
ubifs_release_budget(c, &req);
else {
/* We've deleted something - clean the "no space" flags */
c->bi.nospace = c->bi.nospace_rp = 0;
smp_wmb();
}
return 0;
out_cancel:
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
inc_nlink(dir);
set_nlink(inode, 2);
unlock_2_inodes(dir, inode);
if (budgeted)
ubifs_release_budget(c, &req);
return err;
}
static int ubifs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
struct inode *inode;
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct ubifs_info *c = dir->i_sb->s_fs_info;
int err, sz_change = CALC_DENT_SIZE(dentry->d_name.len);
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
/*
* Budget request settings: new inode, new direntry and changing parent
* directory inode.
*/
dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
dentry, mode, dir->i_ino);
err = ubifs_budget_space(c, &req);
if (err)
return err;
inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_budg;
}
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&dir_ui->ui_mutex);
insert_inode_hash(inode);
inc_nlink(inode);
inc_nlink(dir);
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
if (err) {
ubifs_err(c, "cannot create directory, error %d", err);
goto out_cancel;
}
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
d_instantiate(dentry, inode);
return 0;
out_cancel:
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
drop_nlink(dir);
mutex_unlock(&dir_ui->ui_mutex);
out_inode:
make_bad_inode(inode);
iput(inode);
out_budg:
ubifs_release_budget(c, &req);
return err;
}
static int ubifs_mknod(struct inode *dir, struct dentry *dentry,
umode_t mode, dev_t rdev)
{
struct inode *inode;
struct ubifs_inode *ui;
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct ubifs_info *c = dir->i_sb->s_fs_info;
union ubifs_dev_desc *dev = NULL;
int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
int err, devlen = 0;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.new_ino_d = ALIGN(devlen, 8),
.dirtied_ino = 1 };
/*
* Budget request settings: new inode, new direntry and changing parent
* directory inode.
*/
dbg_gen("dent '%pd' in dir ino %lu", dentry, dir->i_ino);
if (S_ISBLK(mode) || S_ISCHR(mode)) {
dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
if (!dev)
return -ENOMEM;
devlen = ubifs_encode_dev(dev, rdev);
}
err = ubifs_budget_space(c, &req);
if (err) {
kfree(dev);
return err;
}
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
kfree(dev);
err = PTR_ERR(inode);
goto out_budg;
}
init_special_inode(inode, inode->i_mode, rdev);
inode->i_size = ubifs_inode(inode)->ui_size = devlen;
ui = ubifs_inode(inode);
ui->data = dev;
ui->data_len = devlen;
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&dir_ui->ui_mutex);
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
if (err)
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
insert_inode_hash(inode);
d_instantiate(dentry, inode);
return 0;
out_cancel:
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
mutex_unlock(&dir_ui->ui_mutex);
out_inode:
make_bad_inode(inode);
iput(inode);
out_budg:
ubifs_release_budget(c, &req);
return err;
}
static int ubifs_symlink(struct inode *dir, struct dentry *dentry,
const char *symname)
{
struct inode *inode;
struct ubifs_inode *ui;
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct ubifs_info *c = dir->i_sb->s_fs_info;
int err, len = strlen(symname);
int sz_change = CALC_DENT_SIZE(dentry->d_name.len);
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.new_ino_d = ALIGN(len, 8),
.dirtied_ino = 1 };
/*
* Budget request settings: new inode, new direntry and changing parent
* directory inode.
*/
dbg_gen("dent '%pd', target '%s' in dir ino %lu", dentry,
symname, dir->i_ino);
if (len > UBIFS_MAX_INO_DATA)
return -ENAMETOOLONG;
err = ubifs_budget_space(c, &req);
if (err)
return err;
inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_budg;
}
ui = ubifs_inode(inode);
ui->data = kmalloc(len + 1, GFP_NOFS);
if (!ui->data) {
err = -ENOMEM;
goto out_inode;
}
memcpy(ui->data, symname, len);
((char *)ui->data)[len] = '\0';
inode->i_link = ui->data;
/*
* The terminating zero byte is not written to the flash media and it
* is put just to make later in-memory string processing simpler. Thus,
* data length is @len, not @len + %1.
*/
ui->data_len = len;
inode->i_size = ubifs_inode(inode)->ui_size = len;
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&dir_ui->ui_mutex);
dir->i_size += sz_change;
dir_ui->ui_size = dir->i_size;
dir->i_mtime = dir->i_ctime = inode->i_ctime;
err = ubifs_jnl_update(c, dir, &dentry->d_name, inode, 0, 0);
if (err)
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
insert_inode_hash(inode);
d_instantiate(dentry, inode);
return 0;
out_cancel:
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
mutex_unlock(&dir_ui->ui_mutex);
out_inode:
make_bad_inode(inode);
iput(inode);
out_budg:
ubifs_release_budget(c, &req);
return err;
}
/**
* lock_4_inodes - a wrapper for locking three UBIFS inodes.
* @inode1: first inode
* @inode2: second inode
* @inode3: third inode
* @inode4: fouth inode
*
* This function is used for 'ubifs_rename()' and @inode1 may be the same as
* @inode2 whereas @inode3 and @inode4 may be %NULL.
*
* We do not implement any tricks to guarantee strict lock ordering, because
* VFS has already done it for us on the @i_mutex. So this is just a simple
* wrapper function.
*/
static void lock_4_inodes(struct inode *inode1, struct inode *inode2,
struct inode *inode3, struct inode *inode4)
{
mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
if (inode2 != inode1)
mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
if (inode3)
mutex_lock_nested(&ubifs_inode(inode3)->ui_mutex, WB_MUTEX_3);
if (inode4)
mutex_lock_nested(&ubifs_inode(inode4)->ui_mutex, WB_MUTEX_4);
}
/**
* unlock_4_inodes - a wrapper for unlocking three UBIFS inodes for rename.
* @inode1: first inode
* @inode2: second inode
* @inode3: third inode
* @inode4: fouth inode
*/
static void unlock_4_inodes(struct inode *inode1, struct inode *inode2,
struct inode *inode3, struct inode *inode4)
{
if (inode4)
mutex_unlock(&ubifs_inode(inode4)->ui_mutex);
if (inode3)
mutex_unlock(&ubifs_inode(inode3)->ui_mutex);
if (inode1 != inode2)
mutex_unlock(&ubifs_inode(inode2)->ui_mutex);
mutex_unlock(&ubifs_inode(inode1)->ui_mutex);
}
static int ubifs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry,
unsigned int flags)
{
struct ubifs_info *c = old_dir->i_sb->s_fs_info;
struct inode *old_inode = d_inode(old_dentry);
struct inode *new_inode = d_inode(new_dentry);
struct inode *whiteout = NULL;
struct ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
struct ubifs_inode *whiteout_ui = NULL;
int err, release, sync = 0, move = (new_dir != old_dir);
int is_dir = S_ISDIR(old_inode->i_mode);
int unlink = !!new_inode;
int new_sz = CALC_DENT_SIZE(new_dentry->d_name.len);
int old_sz = CALC_DENT_SIZE(old_dentry->d_name.len);
struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
.dirtied_ino = 3 };
struct ubifs_budget_req ino_req = { .dirtied_ino = 1,
.dirtied_ino_d = ALIGN(old_inode_ui->data_len, 8) };
struct timespec time;
unsigned int uninitialized_var(saved_nlink);
if (flags & ~RENAME_NOREPLACE)
return -EINVAL;
/*
* Budget request settings: deletion direntry, new direntry, removing
* the old inode, and changing old and new parent directory inodes.
*
* However, this operation also marks the target inode as dirty and
* does not write it, so we allocate budget for the target inode
* separately.
*/
dbg_gen("dent '%pd' ino %lu in dir ino %lu to dent '%pd' in dir ino %lu flags 0x%x",
old_dentry, old_inode->i_ino, old_dir->i_ino,
new_dentry, new_dir->i_ino, flags);
if (unlink)
ubifs_assert(inode_is_locked(new_inode));
if (unlink && is_dir) {
err = check_dir_empty(c, new_inode);
if (err)
return err;
}
err = ubifs_budget_space(c, &req);
if (err)
return err;
err = ubifs_budget_space(c, &ino_req);
if (err) {
ubifs_release_budget(c, &req);
return err;
}
if (flags & RENAME_WHITEOUT) {
union ubifs_dev_desc *dev = NULL;
dev = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
if (!dev) {
ubifs_release_budget(c, &req);
ubifs_release_budget(c, &ino_req);
return -ENOMEM;
}
err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
if (err) {
ubifs_release_budget(c, &req);
ubifs_release_budget(c, &ino_req);
kfree(dev);
return err;
}
whiteout->i_state |= I_LINKABLE;
whiteout_ui = ubifs_inode(whiteout);
whiteout_ui->data = dev;
whiteout_ui->data_len = ubifs_encode_dev(dev, MKDEV(0, 0));
ubifs_assert(!whiteout_ui->dirty);
}
lock_4_inodes(old_dir, new_dir, new_inode, whiteout);
/*
* Like most other Unix systems, set the @i_ctime for inodes on a
* rename.
*/
time = ubifs_current_time(old_dir);
old_inode->i_ctime = time;
/* We must adjust parent link count when renaming directories */
if (is_dir) {
if (move) {
/*
* @old_dir loses a link because we are moving
* @old_inode to a different directory.
*/
drop_nlink(old_dir);
/*
* @new_dir only gains a link if we are not also
* overwriting an existing directory.
*/
if (!unlink)
inc_nlink(new_dir);
} else {
/*
* @old_inode is not moving to a different directory,
* but @old_dir still loses a link if we are
* overwriting an existing directory.
*/
if (unlink)
drop_nlink(old_dir);
}
}
old_dir->i_size -= old_sz;
ubifs_inode(old_dir)->ui_size = old_dir->i_size;
old_dir->i_mtime = old_dir->i_ctime = time;
new_dir->i_mtime = new_dir->i_ctime = time;
/*
* And finally, if we unlinked a direntry which happened to have the
* same name as the moved direntry, we have to decrement @i_nlink of
* the unlinked inode and change its ctime.
*/
if (unlink) {
/*
* Directories cannot have hard-links, so if this is a
* directory, just clear @i_nlink.
*/
saved_nlink = new_inode->i_nlink;
if (is_dir)
clear_nlink(new_inode);
else
drop_nlink(new_inode);
new_inode->i_ctime = time;
} else {
new_dir->i_size += new_sz;
ubifs_inode(new_dir)->ui_size = new_dir->i_size;
}
/*
* Do not ask 'ubifs_jnl_rename()' to flush write-buffer if @old_inode
* is dirty, because this will be done later on at the end of
* 'ubifs_rename()'.
*/
if (IS_SYNC(old_inode)) {
sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
if (unlink && IS_SYNC(new_inode))
sync = 1;
}
if (whiteout) {
struct ubifs_budget_req wht_req = { .dirtied_ino = 1,
.dirtied_ino_d = \
ALIGN(ubifs_inode(whiteout)->data_len, 8) };
err = ubifs_budget_space(c, &wht_req);
if (err) {
ubifs_release_budget(c, &req);
ubifs_release_budget(c, &ino_req);
kfree(whiteout_ui->data);
whiteout_ui->data_len = 0;
iput(whiteout);
return err;
}
inc_nlink(whiteout);
mark_inode_dirty(whiteout);
whiteout->i_state &= ~I_LINKABLE;
iput(whiteout);
}
err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry, whiteout,
sync);
if (err)
goto out_cancel;
unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
ubifs_release_budget(c, &req);
mutex_lock(&old_inode_ui->ui_mutex);
release = old_inode_ui->dirty;
mark_inode_dirty_sync(old_inode);
mutex_unlock(&old_inode_ui->ui_mutex);
if (release)
ubifs_release_budget(c, &ino_req);
if (IS_SYNC(old_inode))
err = old_inode->i_sb->s_op->write_inode(old_inode, NULL);
return err;
out_cancel:
if (unlink) {
set_nlink(new_inode, saved_nlink);
} else {
new_dir->i_size -= new_sz;
ubifs_inode(new_dir)->ui_size = new_dir->i_size;
}
old_dir->i_size += old_sz;
ubifs_inode(old_dir)->ui_size = old_dir->i_size;
if (is_dir) {
if (move) {
inc_nlink(old_dir);
if (!unlink)
drop_nlink(new_dir);
} else {
if (unlink)
inc_nlink(old_dir);
}
}
if (whiteout) {
drop_nlink(whiteout);
iput(whiteout);
}
unlock_4_inodes(old_dir, new_dir, new_inode, whiteout);
ubifs_release_budget(c, &ino_req);
ubifs_release_budget(c, &req);
return err;
}
static int ubifs_xrename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct ubifs_info *c = old_dir->i_sb->s_fs_info;
struct ubifs_budget_req req = { .new_dent = 1, .mod_dent = 1,
.dirtied_ino = 2 };
int sync = IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir);
struct inode *fst_inode = d_inode(old_dentry);
struct inode *snd_inode = d_inode(new_dentry);
struct timespec time;
int err;
ubifs_assert(fst_inode && snd_inode);
lock_4_inodes(old_dir, new_dir, NULL, NULL);
time = ubifs_current_time(old_dir);
fst_inode->i_ctime = time;
snd_inode->i_ctime = time;
old_dir->i_mtime = old_dir->i_ctime = time;
new_dir->i_mtime = new_dir->i_ctime = time;
if (old_dir != new_dir) {
if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) {
inc_nlink(new_dir);
drop_nlink(old_dir);
}
else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) {
drop_nlink(new_dir);
inc_nlink(old_dir);
}
}
err = ubifs_jnl_xrename(c, old_dir, old_dentry, new_dir, new_dentry,
sync);
unlock_4_inodes(old_dir, new_dir, NULL, NULL);
ubifs_release_budget(c, &req);
return err;
}
static int ubifs_rename2(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry,
unsigned int flags)
{
if (flags & ~(RENAME_NOREPLACE | RENAME_WHITEOUT | RENAME_EXCHANGE))
return -EINVAL;
ubifs_assert(inode_is_locked(old_dir));
ubifs_assert(inode_is_locked(new_dir));
if (flags & RENAME_EXCHANGE)
return ubifs_xrename(old_dir, old_dentry, new_dir, new_dentry);
return ubifs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
}
int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat)
{
loff_t size;
struct inode *inode = d_inode(dentry);
struct ubifs_inode *ui = ubifs_inode(inode);
mutex_lock(&ui->ui_mutex);
generic_fillattr(inode, stat);
stat->blksize = UBIFS_BLOCK_SIZE;
stat->size = ui->ui_size;
/*
* Unfortunately, the 'stat()' system call was designed for block
* device based file systems, and it is not appropriate for UBIFS,
* because UBIFS does not have notion of "block". For example, it is
* difficult to tell how many block a directory takes - it actually
* takes less than 300 bytes, but we have to round it to block size,
* which introduces large mistake. This makes utilities like 'du' to
* report completely senseless numbers. This is the reason why UBIFS
* goes the same way as JFFS2 - it reports zero blocks for everything
* but regular files, which makes more sense than reporting completely
* wrong sizes.
*/
if (S_ISREG(inode->i_mode)) {
size = ui->xattr_size;
size += stat->size;
size = ALIGN(size, UBIFS_BLOCK_SIZE);
/*
* Note, user-space expects 512-byte blocks count irrespectively
* of what was reported in @stat->size.
*/
stat->blocks = size >> 9;
} else
stat->blocks = 0;
mutex_unlock(&ui->ui_mutex);
return 0;
}
const struct inode_operations ubifs_dir_inode_operations = {
.lookup = ubifs_lookup,
.create = ubifs_create,
.link = ubifs_link,
.symlink = ubifs_symlink,
.unlink = ubifs_unlink,
.mkdir = ubifs_mkdir,
.rmdir = ubifs_rmdir,
.mknod = ubifs_mknod,
.rename = ubifs_rename2,
.setattr = ubifs_setattr,
.getattr = ubifs_getattr,
.listxattr = ubifs_listxattr,
#ifdef CONFIG_UBIFS_ATIME_SUPPORT
.update_time = ubifs_update_time,
#endif
.tmpfile = ubifs_tmpfile,
};
const struct file_operations ubifs_dir_operations = {
.llseek = generic_file_llseek,
.release = ubifs_dir_release,
.read = generic_read_dir,
.iterate_shared = ubifs_readdir,
.fsync = ubifs_fsync,
.unlocked_ioctl = ubifs_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ubifs_compat_ioctl,
#endif
};