ubifs: Implement O_TMPFILE

This patchs adds O_TMPFILE support to UBIFS.
A temp file is a reference to an unlinked inode, a user
holding the reference can use it. As soon it is being closed
all data vanishes.

Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Richard Weinberger 2016-09-14 22:28:49 +02:00
parent f7d11b33d4
commit 474b93704f

View file

@ -301,6 +301,76 @@ out_budg:
return err;
}
static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry,
umode_t mode)
{
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;
/*
* 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 = 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;
}
inode = ubifs_new_inode(c, dir, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto out_budg;
}
ui = ubifs_inode(inode);
err = ubifs_init_security(dir, inode, &dentry->d_name);
if (err)
goto out_inode;
mutex_lock(&ui->ui_mutex);
insert_inode_hash(inode);
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, &dentry->d_name, 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);
ubifs_err(c, "cannot create temporary file, error %d", err);
return err;
}
/**
* vfs_dent_type - get VFS directory entry type.
* @type: UBIFS directory entry type
@ -1189,6 +1259,7 @@ const struct inode_operations ubifs_dir_inode_operations = {
#ifdef CONFIG_UBIFS_ATIME_SUPPORT
.update_time = ubifs_update_time,
#endif
.tmpfile = ubifs_tmpfile,
};
const struct file_operations ubifs_dir_operations = {