static struct dentry *au_lkup_by_ino(struct path *path, ino_t ino,
struct au_nfsd_si_lock *nsi_lock)
{
struct dentry *dentry, *parent;
struct file *file;
struct inode *dir;
struct find_name_by_ino arg;
int err;
parent = path->dentry;
if (nsi_lock)
si_read_unlock(parent->d_sb);
file = vfsub_dentry_open(path, au_dir_roflags);
dentry = (void *)file;
if (IS_ERR(file))
goto out;
dentry = ERR_PTR(-ENOMEM);
arg.name = __getname_gfp(GFP_NOFS);
if (unlikely(!arg.name))
goto out_file;
arg.ino = ino;
arg.found = 0;
do {
arg.called = 0;
/* smp_mb(); */
err = vfsub_readdir(file, find_name_by_ino, &arg);
} while (!err && !arg.found && arg.called);
dentry = ERR_PTR(err);
if (unlikely(err))
goto out_name;
dentry = ERR_PTR(-ENOENT);
if (!arg.found)
goto out_name;
/* do not call au_lkup_one() */
dir = parent->d_inode;
mutex_lock(&dir->i_mutex);
dentry = vfsub_lookup_one_len(arg.name, parent, arg.namelen);
mutex_unlock(&dir->i_mutex);
AuTraceErrPtr(dentry);
if (IS_ERR(dentry))
goto out_name;
AuDebugOn(au_test_anon(dentry));
if (unlikely(!dentry->d_inode)) {
dput(dentry);
dentry = ERR_PTR(-ENOENT);
}
out_name:
__putname(arg.name);
out_file:
fput(file);
out:
if (unlikely(nsi_lock
&& si_nfsd_read_lock(parent->d_sb, nsi_lock) < 0))
if (!IS_ERR(dentry)) {
dput(dentry);
dentry = ERR_PTR(-ESTALE);
}
AuTraceErrPtr(dentry);
return dentry;
}
/* common functions to regular file and dir */
struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags,
struct file *file)
{
struct file *h_file;
struct dentry *h_dentry;
struct inode *h_inode;
struct super_block *sb;
struct au_branch *br;
struct path h_path;
int err, exec_flag;
/* a race condition can happen between open and unlink/rmdir */
h_file = ERR_PTR(-ENOENT);
h_dentry = au_h_dptr(dentry, bindex);
if (au_test_nfsd() && !h_dentry)
goto out;
h_inode = h_dentry->d_inode;
if (au_test_nfsd() && !h_inode)
goto out;
spin_lock(&h_dentry->d_lock);
err = (!d_unhashed(dentry) && d_unlinked(h_dentry))
|| !h_inode
/* || !dentry->d_inode->i_nlink */
;
spin_unlock(&h_dentry->d_lock);
if (unlikely(err))
goto out;
sb = dentry->d_sb;
br = au_sbr(sb, bindex);
h_file = ERR_PTR(-EACCES);
exec_flag = flags & __FMODE_EXEC;
if (exec_flag && (br->br_mnt->mnt_flags & MNT_NOEXEC))
goto out;
/* drop flags for writing */
if (au_test_ro(sb, bindex, dentry->d_inode))
flags = au_file_roflags(flags);
flags &= ~O_CREAT;
atomic_inc(&br->br_count);
h_path.dentry = h_dentry;
h_path.mnt = br->br_mnt;
if (!au_special_file(h_inode->i_mode))
h_file = vfsub_dentry_open(&h_path, flags);
else {
/* this block depends upon the configuration */
di_read_unlock(dentry, AuLock_IR);
fi_write_unlock(file);
si_read_unlock(sb);
h_file = vfsub_dentry_open(&h_path, flags);
si_noflush_read_lock(sb);
fi_write_lock(file);
di_read_lock_child(dentry, AuLock_IR);
}
if (IS_ERR(h_file))
goto out_br;
if (exec_flag) {
err = deny_write_access(h_file);
if (unlikely(err)) {
fput(h_file);
h_file = ERR_PTR(err);
goto out_br;
}
}
fsnotify_open(h_file);
goto out; /* success */
out_br:
atomic_dec(&br->br_count);
out:
return h_file;
}
/* common functions to regular file and dir */
struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags,
struct file *file, int force_wr)
{
struct file *h_file;
struct dentry *h_dentry;
struct inode *h_inode;
struct super_block *sb;
struct au_branch *br;
struct path h_path;
int err, exec_flag;
/* a race condition can happen between open and unlink/rmdir */
h_file = ERR_PTR(-ENOENT);
h_dentry = au_h_dptr(dentry, bindex);
if (au_test_nfsd() && !h_dentry)
goto out;
h_inode = h_dentry->d_inode;
if (au_test_nfsd() && !h_inode)
goto out;
spin_lock(&h_dentry->d_lock);
err = (!d_unhashed(dentry) && d_unlinked(h_dentry))
|| !h_inode
/* || !dentry->d_inode->i_nlink */
;
spin_unlock(&h_dentry->d_lock);
if (unlikely(err))
goto out;
sb = dentry->d_sb;
br = au_sbr(sb, bindex);
h_file = ERR_PTR(-EACCES);
exec_flag = flags & __FMODE_EXEC;
if (exec_flag && (au_br_mnt(br)->mnt_flags & MNT_NOEXEC))
goto out;
/* drop flags for writing */
if (au_test_ro(sb, bindex, dentry->d_inode)) {
if (force_wr && !(flags & O_WRONLY))
force_wr = 0;
flags = au_file_roflags(flags);
if (force_wr) {
h_file = ERR_PTR(-EROFS);
flags = au_file_roflags(flags);
if (unlikely(vfsub_native_ro(h_inode)
|| IS_APPEND(h_inode)))
goto out;
flags &= ~O_ACCMODE;
flags |= O_WRONLY;
}
}
flags &= ~O_CREAT;
atomic_inc(&br->br_count);
h_path.dentry = h_dentry;
h_path.mnt = au_br_mnt(br);
h_file = vfsub_dentry_open(&h_path, flags);
if (IS_ERR(h_file))
goto out_br;
if (exec_flag) {
err = deny_write_access(h_file);
if (unlikely(err)) {
fput(h_file);
h_file = ERR_PTR(err);
goto out_br;
}
}
fsnotify_open(h_file);
goto out; /* success */
out_br:
atomic_dec(&br->br_count);
out:
return h_file;
}