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(mutex_is_locked(&dir->i_mutex));
ubifs_assert(mutex_is_locked(&inode->i_mutex));
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(mutex_is_locked(&dir->i_mutex));
ubifs_assert(mutex_is_locked(&inode->i_mutex));
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(mutex_is_locked(&dir->i_mutex));
ubifs_assert(mutex_is_locked(&inode->i_mutex));
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 (!new_valid_dev(rdev))
return -EINVAL;
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_3_inodes - a wrapper for locking three UBIFS inodes.
* @inode1: first inode
* @inode2: second inode
* @inode3: third inode
*
* This function is used for 'ubifs_rename()' and @inode1 may be the same as
* @inode2 whereas @inode3 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_3_inodes(struct inode *inode1, struct inode *inode2,
struct inode *inode3)
{
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);
}
/**
* unlock_3_inodes - a wrapper for unlocking three UBIFS inodes for rename.
* @inode1: first inode
* @inode2: second inode
* @inode3: third inode
*/
static void unlock_3_inodes(struct inode *inode1, struct inode *inode2,
struct inode *inode3)
{
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)
{
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 ubifs_inode *old_inode_ui = ubifs_inode(old_inode);
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);
/*
* 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",
old_dentry, old_inode->i_ino, old_dir->i_ino,
new_dentry, new_dir->i_ino);
ubifs_assert(mutex_is_locked(&old_dir->i_mutex));
ubifs_assert(mutex_is_locked(&new_dir->i_mutex));
if (unlink)
ubifs_assert(mutex_is_locked(&new_inode->i_mutex));
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;
}
lock_3_inodes(old_dir, new_dir, new_inode);
/*
* 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;
}
err = ubifs_jnl_rename(c, old_dir, old_dentry, new_dir, new_dentry,
sync);
if (err)
goto out_cancel;
unlock_3_inodes(old_dir, new_dir, new_inode);
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);
}
}
unlock_3_inodes(old_dir, new_dir, new_inode);
ubifs_release_budget(c, &ino_req);
ubifs_release_budget(c, &req);
return err;
}
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_rename,
.setattr = ubifs_setattr,
.getattr = ubifs_getattr,
.setxattr = ubifs_setxattr,
.getxattr = ubifs_getxattr,
.listxattr = ubifs_listxattr,
.removexattr = ubifs_removexattr,
};
const struct file_operations ubifs_dir_operations = {
.llseek = generic_file_llseek,
.release = ubifs_dir_release,
.read = generic_read_dir,
.iterate = ubifs_readdir,
.fsync = ubifs_fsync,
.unlocked_ioctl = ubifs_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ubifs_compat_ioctl,
#endif
};
static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool excl)
{
struct inode *inode;
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,
.dirtied_ino = 1 };
struct ubifs_inode *dir_ui = ubifs_inode(dir);
/*
* Budget request settings: new inode, new direntry, changing the
* 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, 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);
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);
ubifs_err(c, "cannot create regular file, error %d", err);
return err;
}
/**
* vfs_dent_type - get VFS directory entry type.
* @type: UBIFS directory entry type
*
* This function converts UBIFS directory entry type into VFS directory entry
* type.
*/
static unsigned int vfs_dent_type(uint8_t type)
{
switch (type) {
case UBIFS_ITYPE_REG:
return DT_REG;
case UBIFS_ITYPE_DIR:
return DT_DIR;
case UBIFS_ITYPE_LNK:
return DT_LNK;
case UBIFS_ITYPE_BLK:
return DT_BLK;
case UBIFS_ITYPE_CHR:
return DT_CHR;
case UBIFS_ITYPE_FIFO:
return DT_FIFO;
case UBIFS_ITYPE_SOCK:
return DT_SOCK;
default:
BUG();
}
return 0;
}
/*
* The classical Unix view for directory is that it is a linear array of
* (name, inode number) entries. Linux/VFS assumes this model as well.
* Particularly, 'readdir()' call wants us to return a directory entry offset
* which later may be used to continue 'readdir()'ing the directory or to
* 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
* model because directory entries are identified by keys, which may collide.
*
* UBIFS uses directory entry hash value for directory offsets, so
* 'seekdir()'/'telldir()' may not always work because of possible key
* collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
* properly by means of saving full directory entry name in the private field
* of the file description object.
*
* This means that UBIFS cannot support NFS which requires full
* 'seekdir()'/'telldir()' support.
*/
static int ubifs_readdir(struct file *file, struct dir_context *ctx)
{
int err;
struct qstr nm;
union ubifs_key key;
struct ubifs_dent_node *dent;
struct inode *dir = file_inode(file);
struct ubifs_info *c = dir->i_sb->s_fs_info;
dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
/*
* The directory was seek'ed to a senseless position or there
* are no more entries.
*/
return 0;
if (file->f_version == 0) {
/*
* The file was seek'ed, which means that @file->private_data
* is now invalid. This may also be just the first
* 'ubifs_readdir()' invocation, in which case
* @file->private_data is NULL, and the below code is
* basically a no-op.
*/
kfree(file->private_data);
file->private_data = NULL;
}
/*
* 'generic_file_llseek()' unconditionally sets @file->f_version to
* zero, and we use this for detecting whether the file was seek'ed.
*/
file->f_version = 1;
/* File positions 0 and 1 correspond to "." and ".." */
if (ctx->pos < 2) {
ubifs_assert(!file->private_data);
if (!dir_emit_dots(file, ctx))
return 0;
/* Find the first entry in TNC and save it */
lowest_dent_key(c, &key, dir->i_ino);
nm.name = NULL;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
dent = file->private_data;
if (!dent) {
/*
* The directory was seek'ed to and is now readdir'ed.
* Find the entry corresponding to @ctx->pos or the closest one.
*/
dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
nm.name = NULL;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
while (1) {
dbg_gen("feed '%s', ino %llu, new f_pos %#x",
dent->name, (unsigned long long)le64_to_cpu(dent->inum),
key_hash_flash(c, &dent->key));
ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
ubifs_inode(dir)->creat_sqnum);
nm.len = le16_to_cpu(dent->nlen);
if (!dir_emit(ctx, dent->name, nm.len,
le64_to_cpu(dent->inum),
vfs_dent_type(dent->type)))
return 0;
/* Switch to the next entry */
key_read(c, &dent->key, &key);
nm.name = dent->name;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
kfree(file->private_data);
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
cond_resched();
}
out:
if (err != -ENOENT) {
ubifs_err(c, "cannot find next direntry, error %d", err);
return err;
}
kfree(file->private_data);
file->private_data = NULL;
/* 2 is a special value indicating that there are no more direntries */
ctx->pos = 2;
return 0;
}
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) };
struct fscrypt_name nm;
/*
* 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));
if (ubifs_crypt_is_encrypted(dir) &&
!fscrypt_has_permitted_context(dir, inode))
return -EPERM;
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err)
return err;
err = dbg_check_synced_i_size(c, inode);
if (err)
goto out_fname;
err = ubifs_budget_space(c, &req);
if (err)
goto out_fname;
lock_2_inodes(dir, inode);
/* Handle O_TMPFILE corner case, it is allowed to link a O_TMPFILE. */
if (inode->i_nlink == 0)
ubifs_delete_orphan(c, inode->i_ino);
inc_nlink(inode);
ihold(inode);
inode->i_ctime = 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, &nm, inode, 0, 0);
if (err)
goto out_cancel;
unlock_2_inodes(dir, inode);
ubifs_release_budget(c, &req);
d_instantiate(dentry, inode);
fscrypt_free_filename(&nm);
return 0;
out_cancel:
dir->i_size -= sz_change;
dir_ui->ui_size = dir->i_size;
drop_nlink(inode);
if (inode->i_nlink == 0)
ubifs_add_orphan(c, inode->i_ino);
unlock_2_inodes(dir, inode);
ubifs_release_budget(c, &req);
iput(inode);
out_fname:
fscrypt_free_filename(&nm);
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 err, sz_change, budgeted = 1;
struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
unsigned int saved_nlink = inode->i_nlink;
struct fscrypt_name nm;
/*
* 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);
if (ubifs_crypt_is_encrypted(dir)) {
err = fscrypt_get_encryption_info(dir);
if (err && err != -ENOKEY)
return err;
}
err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
if (err)
return err;
sz_change = CALC_DENT_SIZE(fname_len(&nm));
ubifs_assert(inode_is_locked(dir));
ubifs_assert(inode_is_locked(inode));
err = dbg_check_synced_i_size(c, inode);
if (err)
goto out_fname;
err = ubifs_budget_space(c, &req);
if (err) {
if (err != -ENOSPC)
goto out_fname;
budgeted = 0;
}
lock_2_inodes(dir, inode);
inode->i_ctime = 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, &nm, 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();
}
fscrypt_free_filename(&nm);
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);
out_fname:
fscrypt_free_filename(&nm);
return err;
}
/**
* check_dir_empty - check if a directory is empty or not.
* @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.
*/
int ubifs_check_dir_empty(struct inode *dir)
{
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct fscrypt_name nm = { 0 };
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 err, sz_change, budgeted = 1;
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct ubifs_budget_req req = { .mod_dent = 1, .dirtied_ino = 2 };
struct fscrypt_name nm;
/*
* 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 = ubifs_check_dir_empty(d_inode(dentry));
if (err)
return err;
if (ubifs_crypt_is_encrypted(dir)) {
err = fscrypt_get_encryption_info(dir);
if (err && err != -ENOKEY)
return err;
}
err = fscrypt_setup_filename(dir, &dentry->d_name, 1, &nm);
if (err)
return err;
sz_change = CALC_DENT_SIZE(fname_len(&nm));
err = ubifs_budget_space(c, &req);
if (err) {
if (err != -ENOSPC)
goto out_fname;
budgeted = 0;
}
lock_2_inodes(dir, inode);
inode->i_ctime = 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, &nm, 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();
}
fscrypt_free_filename(&nm);
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);
out_fname:
fscrypt_free_filename(&nm);
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;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1 };
struct fscrypt_name nm;
/*
* 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;
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err)
goto out_budg;
sz_change = CALC_DENT_SIZE(fname_len(&nm));
inode = ubifs_new_inode(c, dir, S_IFDIR | mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_fname;
}
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, &nm, 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);
fscrypt_free_filename(&nm);
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_fname:
fscrypt_free_filename(&nm);
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;
int err, devlen = 0;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.dirtied_ino = 1 };
struct fscrypt_name nm;
/*
* 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);
}
req.new_ino_d = ALIGN(devlen, 8);
err = ubifs_budget_space(c, &req);
if (err) {
kfree(dev);
return err;
}
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err) {
kfree(dev);
goto out_budg;
}
sz_change = CALC_DENT_SIZE(fname_len(&nm));
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
kfree(dev);
err = PTR_ERR(inode);
goto out_fname;
}
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, &nm, 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);
fscrypt_free_filename(&nm);
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_fname:
fscrypt_free_filename(&nm);
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(len);
struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1);
struct fscrypt_symlink_data *sd = NULL;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.new_ino_d = ALIGN(len, 8),
.dirtied_ino = 1 };
struct fscrypt_name nm;
if (ubifs_crypt_is_encrypted(dir)) {
err = fscrypt_get_encryption_info(dir);
if (err)
goto out_budg;
if (!fscrypt_has_encryption_key(dir)) {
err = -EPERM;
goto out_budg;
}
disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
sizeof(struct fscrypt_symlink_data));
}
/*
* 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 (disk_link.len > UBIFS_MAX_INO_DATA)
return -ENAMETOOLONG;
err = ubifs_budget_space(c, &req);
if (err)
return err;
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err)
goto out_budg;
inode = ubifs_new_inode(c, dir, S_IFLNK | S_IRWXUGO);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_fname;
}
ui = ubifs_inode(inode);
ui->data = kmalloc(disk_link.len, GFP_NOFS);
if (!ui->data) {
err = -ENOMEM;
goto out_inode;
}
if (ubifs_crypt_is_encrypted(dir)) {
struct qstr istr = QSTR_INIT(symname, len);
struct fscrypt_str ostr;
sd = kzalloc(disk_link.len, GFP_NOFS);
if (!sd) {
err = -ENOMEM;
goto out_inode;
}
ostr.name = sd->encrypted_path;
ostr.len = disk_link.len;
err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
if (err) {
kfree(sd);
goto out_inode;
}
sd->len = cpu_to_le16(ostr.len);
disk_link.name = (char *)sd;
} else {
inode->i_link = ui->data;
}
memcpy(ui->data, disk_link.name, disk_link.len);
((char *)ui->data)[disk_link.len - 1] = '\0';
/*
* 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 = disk_link.len - 1;
inode->i_size = ubifs_inode(inode)->ui_size = disk_link.len - 1;
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, &nm, 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);
fscrypt_free_filename(&nm);
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_fname:
fscrypt_free_filename(&nm);
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 do_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, new_sz, old_sz;
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);
struct fscrypt_name old_nm, new_nm;
/*
* 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 (old_dir != new_dir) {
if (ubifs_crypt_is_encrypted(new_dir) &&
!fscrypt_has_permitted_context(new_dir, old_inode))
return -EPERM;
}
if (unlink && is_dir) {
err = ubifs_check_dir_empty(new_inode);
if (err)
return err;
}
err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &old_nm);
if (err)
return err;
err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &new_nm);
if (err) {
fscrypt_free_filename(&old_nm);
return err;
}
new_sz = CALC_DENT_SIZE(fname_len(&new_nm));
old_sz = CALC_DENT_SIZE(fname_len(&old_nm));
err = ubifs_budget_space(c, &req);
if (err) {
fscrypt_free_filename(&old_nm);
fscrypt_free_filename(&new_nm);
return err;
}
err = ubifs_budget_space(c, &ino_req);
if (err) {
fscrypt_free_filename(&old_nm);
fscrypt_free_filename(&new_nm);
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) {
err = -ENOMEM;
goto out_release;
}
err = do_tmpfile(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE, &whiteout);
if (err) {
kfree(dev);
goto out_release;
}
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 = 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) {
kfree(whiteout_ui->data);
whiteout_ui->data_len = 0;
iput(whiteout);
goto out_release;
}
inc_nlink(whiteout);
mark_inode_dirty(whiteout);
whiteout->i_state &= ~I_LINKABLE;
iput(whiteout);
}
err = ubifs_jnl_rename(c, old_dir, old_inode, &old_nm, new_dir,
new_inode, &new_nm, 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);
fscrypt_free_filename(&old_nm);
fscrypt_free_filename(&new_nm);
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);
out_release:
ubifs_release_budget(c, &ino_req);
ubifs_release_budget(c, &req);
fscrypt_free_filename(&old_nm);
fscrypt_free_filename(&new_nm);
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;
struct fscrypt_name fst_nm, snd_nm;
ubifs_assert(fst_inode && snd_inode);
if ((ubifs_crypt_is_encrypted(old_dir) ||
ubifs_crypt_is_encrypted(new_dir)) &&
(old_dir != new_dir) &&
(!fscrypt_has_permitted_context(new_dir, fst_inode) ||
!fscrypt_has_permitted_context(old_dir, snd_inode)))
return -EPERM;
err = fscrypt_setup_filename(old_dir, &old_dentry->d_name, 0, &fst_nm);
if (err)
return err;
err = fscrypt_setup_filename(new_dir, &new_dentry->d_name, 0, &snd_nm);
if (err) {
fscrypt_free_filename(&fst_nm);
return err;
}
lock_4_inodes(old_dir, new_dir, NULL, NULL);
time = 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, fst_inode, &fst_nm, new_dir,
snd_inode, &snd_nm, sync);
unlock_4_inodes(old_dir, new_dir, NULL, NULL);
ubifs_release_budget(c, &req);
fscrypt_free_filename(&fst_nm);
fscrypt_free_filename(&snd_nm);
return err;
}
static int ubifs_rename(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 do_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
}
int ubifs_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags)
{
loff_t size;
struct inode *inode = d_inode(path->dentry);
struct ubifs_inode *ui = ubifs_inode(inode);
mutex_lock(&ui->ui_mutex);
if (ui->flags & UBIFS_APPEND_FL)
stat->attributes |= STATX_ATTR_APPEND;
if (ui->flags & UBIFS_COMPR_FL)
stat->attributes |= STATX_ATTR_COMPRESSED;
if (ui->flags & UBIFS_CRYPT_FL)
stat->attributes |= STATX_ATTR_ENCRYPTED;
if (ui->flags & UBIFS_IMMUTABLE_FL)
stat->attributes |= STATX_ATTR_IMMUTABLE;
stat->attributes_mask |= (STATX_ATTR_APPEND |
STATX_ATTR_COMPRESSED |
STATX_ATTR_ENCRYPTED |
STATX_ATTR_IMMUTABLE);
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;
}
static int ubifs_dir_open(struct inode *dir, struct file *file)
{
if (ubifs_crypt_is_encrypted(dir))
return fscrypt_get_encryption_info(dir) ? -EACCES : 0;
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_rename,
.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,
.open = ubifs_dir_open,
#ifdef CONFIG_COMPAT
.compat_ioctl = ubifs_compat_ioctl,
#endif
};
static int ubifs_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd)
{
struct inode *inode;
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,
.dirtied_ino = 1 };
struct ubifs_inode *dir_ui = ubifs_inode(dir);
/*
* Budget request settings: new inode, new direntry, changing the
* parent directory inode.
*/
dbg_gen("dent '%.*s', mode %#x in dir ino %lu",
dentry->d_name.len, dentry->d_name.name, mode, dir->i_ino);
err = ubifs_budget_space(c, &req);
if (err)
return err;
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_budg;
}
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);
make_bad_inode(inode);
iput(inode);
out_budg:
ubifs_release_budget(c, &req);
ubifs_err("cannot create regular file, error %d", err);
return err;
}
static unsigned int vfs_dent_type(uint8_t type)
{
switch (type) {
case UBIFS_ITYPE_REG:
return DT_REG;
case UBIFS_ITYPE_DIR:
return DT_DIR;
case UBIFS_ITYPE_LNK:
return DT_LNK;
case UBIFS_ITYPE_BLK:
return DT_BLK;
case UBIFS_ITYPE_CHR:
return DT_CHR;
case UBIFS_ITYPE_FIFO:
return DT_FIFO;
case UBIFS_ITYPE_SOCK:
return DT_SOCK;
default:
BUG();
}
return 0;
}
static int ubifs_readdir(struct file *file, void *dirent, filldir_t filldir)
{
int err, over = 0;
struct qstr nm;
union ubifs_key key;
struct ubifs_dent_node *dent;
struct inode *dir = file->f_path.dentry->d_inode;
struct ubifs_info *c = dir->i_sb->s_fs_info;
dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos);
if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2)
/*
* The directory was seek'ed to a senseless position or there
* are no more entries.
*/
return 0;
/* File positions 0 and 1 correspond to "." and ".." */
if (file->f_pos == 0) {
ubifs_assert(!file->private_data);
over = filldir(dirent, ".", 1, 0, dir->i_ino, DT_DIR);
if (over)
return 0;
file->f_pos = 1;
}
if (file->f_pos == 1) {
ubifs_assert(!file->private_data);
over = filldir(dirent, "..", 2, 1,
parent_ino(file->f_path.dentry), DT_DIR);
if (over)
return 0;
/* Find the first entry in TNC and save it */
lowest_dent_key(c, &key, dir->i_ino);
nm.name = NULL;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
file->f_pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
dent = file->private_data;
if (!dent) {
/*
* The directory was seek'ed to and is now readdir'ed.
* Find the entry corresponding to @file->f_pos or the
* closest one.
*/
dent_key_init_hash(c, &key, dir->i_ino, file->f_pos);
nm.name = NULL;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
file->f_pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
while (1) {
dbg_gen("feed '%s', ino %llu, new f_pos %#x",
dent->name, (unsigned long long)le64_to_cpu(dent->inum),
key_hash_flash(c, &dent->key));
ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
ubifs_inode(dir)->creat_sqnum);
nm.len = le16_to_cpu(dent->nlen);
over = filldir(dirent, dent->name, nm.len, file->f_pos,
le64_to_cpu(dent->inum),
vfs_dent_type(dent->type));
if (over)
return 0;
/* Switch to the next entry */
key_read(c, &dent->key, &key);
nm.name = dent->name;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
kfree(file->private_data);
file->f_pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
cond_resched();
}
out:
if (err != -ENOENT) {
ubifs_err("cannot find next direntry, error %d", err);
return err;
}
kfree(file->private_data);
file->private_data = NULL;
file->f_pos = 2;
return 0;
}
static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool excl)
{
struct inode *inode;
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
.dirtied_ino = 1 };
struct ubifs_inode *dir_ui = ubifs_inode(dir);
struct fscrypt_name nm;
int err, sz_change;
/*
* Budget request settings: new inode, new direntry, changing the
* 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;
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err)
goto out_budg;
sz_change = CALC_DENT_SIZE(fname_len(&nm));
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_fname;
}
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, &nm, inode, 0, 0);
if (err)
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
fscrypt_free_filename(&nm);
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_fname:
fscrypt_free_filename(&nm);
out_budg:
ubifs_release_budget(c, &req);
ubifs_err(c, "cannot create regular file, error %d", err);
return err;
}
static int do_tmpfile(struct inode *dir, struct dentry *dentry,
umode_t mode, struct inode **whiteout)
{
struct inode *inode;
struct ubifs_info *c = dir->i_sb->s_fs_info;
struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1};
struct ubifs_budget_req ino_req = { .dirtied_ino = 1 };
struct ubifs_inode *ui, *dir_ui = ubifs_inode(dir);
int err, instantiated = 0;
struct fscrypt_name nm;
/*
* Budget request settings: new dirty inode, new direntry,
* budget for dirtied inode will be released via writeback.
*/
dbg_gen("dent '%pd', mode %#hx in dir ino %lu",
dentry, mode, dir->i_ino);
err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm);
if (err)
return err;
err = ubifs_budget_space(c, &req);
if (err) {
fscrypt_free_filename(&nm);
return err;
}
err = ubifs_budget_space(c, &ino_req);
if (err) {
ubifs_release_budget(c, &req);
fscrypt_free_filename(&nm);
return err;
}
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_budg;
}
ui = ubifs_inode(inode);
if (whiteout) {
init_special_inode(inode, inode->i_mode, WHITEOUT_DEV);
ubifs_assert(inode->i_op == &ubifs_file_inode_operations);
}
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&ui->ui_mutex);
insert_inode_hash(inode);
if (whiteout) {
mark_inode_dirty(inode);
drop_nlink(inode);
*whiteout = inode;
} else {
d_tmpfile(dentry, inode);
}
ubifs_assert(ui->dirty);
instantiated = 1;
mutex_unlock(&ui->ui_mutex);
mutex_lock(&dir_ui->ui_mutex);
err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0);
if (err)
goto out_cancel;
mutex_unlock(&dir_ui->ui_mutex);
ubifs_release_budget(c, &req);
return 0;
out_cancel:
mutex_unlock(&dir_ui->ui_mutex);
out_inode:
make_bad_inode(inode);
if (!instantiated)
iput(inode);
out_budg:
ubifs_release_budget(c, &req);
if (!instantiated)
ubifs_release_budget(c, &ino_req);
fscrypt_free_filename(&nm);
ubifs_err(c, "cannot create temporary file, error %d", err);
return err;
}
static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
umode_t mode)
{
return do_tmpfile(dir, dentry, mode, NULL);
}
/**
* vfs_dent_type - get VFS directory entry type.
* @type: UBIFS directory entry type
*
* This function converts UBIFS directory entry type into VFS directory entry
* type.
*/
static unsigned int vfs_dent_type(uint8_t type)
{
switch (type) {
case UBIFS_ITYPE_REG:
return DT_REG;
case UBIFS_ITYPE_DIR:
return DT_DIR;
case UBIFS_ITYPE_LNK:
return DT_LNK;
case UBIFS_ITYPE_BLK:
return DT_BLK;
case UBIFS_ITYPE_CHR:
return DT_CHR;
case UBIFS_ITYPE_FIFO:
return DT_FIFO;
case UBIFS_ITYPE_SOCK:
return DT_SOCK;
default:
BUG();
}
return 0;
}
/*
* The classical Unix view for directory is that it is a linear array of
* (name, inode number) entries. Linux/VFS assumes this model as well.
* Particularly, 'readdir()' call wants us to return a directory entry offset
* which later may be used to continue 'readdir()'ing the directory or to
* 'seek()' to that specific direntry. Obviously UBIFS does not really fit this
* model because directory entries are identified by keys, which may collide.
*
* UBIFS uses directory entry hash value for directory offsets, so
* 'seekdir()'/'telldir()' may not always work because of possible key
* collisions. But UBIFS guarantees that consecutive 'readdir()' calls work
* properly by means of saving full directory entry name in the private field
* of the file description object.
*
* This means that UBIFS cannot support NFS which requires full
* 'seekdir()'/'telldir()' support.
*/
static int ubifs_readdir(struct file *file, struct dir_context *ctx)
{
int fstr_real_len = 0, err = 0;
struct fscrypt_name nm;
struct fscrypt_str fstr = {0};
union ubifs_key key;
struct ubifs_dent_node *dent;
struct inode *dir = file_inode(file);
struct ubifs_info *c = dir->i_sb->s_fs_info;
bool encrypted = ubifs_crypt_is_encrypted(dir);
dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos);
if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2)
/*
* The directory was seek'ed to a senseless position or there
* are no more entries.
*/
return 0;
if (encrypted) {
err = fscrypt_get_encryption_info(dir);
if (err && err != -ENOKEY)
return err;
err = fscrypt_fname_alloc_buffer(dir, UBIFS_MAX_NLEN, &fstr);
if (err)
return err;
fstr_real_len = fstr.len;
}
if (file->f_version == 0) {
/*
* The file was seek'ed, which means that @file->private_data
* is now invalid. This may also be just the first
* 'ubifs_readdir()' invocation, in which case
* @file->private_data is NULL, and the below code is
* basically a no-op.
*/
kfree(file->private_data);
file->private_data = NULL;
}
/*
* 'generic_file_llseek()' unconditionally sets @file->f_version to
* zero, and we use this for detecting whether the file was seek'ed.
*/
file->f_version = 1;
/* File positions 0 and 1 correspond to "." and ".." */
if (ctx->pos < 2) {
ubifs_assert(!file->private_data);
if (!dir_emit_dots(file, ctx)) {
if (encrypted)
fscrypt_fname_free_buffer(&fstr);
return 0;
}
/* Find the first entry in TNC and save it */
lowest_dent_key(c, &key, dir->i_ino);
fname_len(&nm) = 0;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
dent = file->private_data;
if (!dent) {
/*
* The directory was seek'ed to and is now readdir'ed.
* Find the entry corresponding to @ctx->pos or the closest one.
*/
dent_key_init_hash(c, &key, dir->i_ino, ctx->pos);
fname_len(&nm) = 0;
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
}
while (1) {
dbg_gen("ino %llu, new f_pos %#x",
(unsigned long long)le64_to_cpu(dent->inum),
key_hash_flash(c, &dent->key));
ubifs_assert(le64_to_cpu(dent->ch.sqnum) >
ubifs_inode(dir)->creat_sqnum);
fname_len(&nm) = le16_to_cpu(dent->nlen);
fname_name(&nm) = dent->name;
if (encrypted) {
fstr.len = fstr_real_len;
err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c,
&dent->key),
le32_to_cpu(dent->cookie),
&nm.disk_name, &fstr);
if (err)
goto out;
} else {
fstr.len = fname_len(&nm);
fstr.name = fname_name(&nm);
}
if (!dir_emit(ctx, fstr.name, fstr.len,
le64_to_cpu(dent->inum),
vfs_dent_type(dent->type))) {
if (encrypted)
fscrypt_fname_free_buffer(&fstr);
return 0;
}
/* Switch to the next entry */
key_read(c, &dent->key, &key);
dent = ubifs_tnc_next_ent(c, &key, &nm);
if (IS_ERR(dent)) {
err = PTR_ERR(dent);
goto out;
}
kfree(file->private_data);
ctx->pos = key_hash_flash(c, &dent->key);
file->private_data = dent;
cond_resched();
}
out:
kfree(file->private_data);
file->private_data = NULL;
if (encrypted)
fscrypt_fname_free_buffer(&fstr);
if (err != -ENOENT)
ubifs_err(c, "cannot find next direntry, error %d", err);
else
/*
* -ENOENT is a non-fatal error in this context, the TNC uses
* it to indicate that the cursor moved past the current directory
* and readdir() has to stop.
*/
err = 0;
/* 2 is a special value indicating that there are no more direntries */
ctx->pos = 2;
return err;
}
/* Free saved readdir() state when the directory is closed */
static int ubifs_dir_release(struct inode *dir, struct file *file)
{
kfree(file->private_data);
file->private_data = NULL;
return 0;
}
/**
* lock_2_inodes - a wrapper for locking two UBIFS inodes.
* @inode1: first inode
* @inode2: second inode
*
* 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_2_inodes(struct inode *inode1, struct inode *inode2)
{
mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1);
mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2);
}