static int noinline_for_stack
au_opts_parse_mod(struct au_opt_mod *mod, substring_t args[])
{
int err;
struct path path;
char *p;
err = -EINVAL;
mod->path = args[0].from;
p = strchr(mod->path, '=');
if (unlikely(!p)) {
pr_err("no permssion %s\n", args[0].from);
goto out;
}
*p++ = 0;
err = vfsub_kern_path(mod->path, lkup_dirflags, &path);
if (unlikely(err)) {
pr_err("lookup failed %s (%d)\n", mod->path, err);
goto out;
}
mod->perm = br_perm_val(p);
AuDbg("mod path %s, perm 0x%x, %s\n", mod->path, mod->perm, p);
mod->h_root = dget(path.dentry);
path_put(&path);
out:
return err;
}
static int opt_add(struct au_opt *opt, char *opt_str, unsigned long sb_flags,
aufs_bindex_t bindex)
{
int err;
struct au_opt_add *add = &opt->add;
char *p;
add->bindex = bindex;
add->perm = AuBrPerm_RO;
add->pathname = opt_str;
p = strchr(opt_str, '=');
if (p) {
*p++ = 0;
if (*p)
add->perm = br_perm_val(p);
}
err = vfsub_kern_path(add->pathname, lkup_dirflags, &add->path);
if (!err) {
if (!p) {
add->perm = AuBrPerm_RO;
if (au_test_fs_rr(add->path.dentry->d_sb))
add->perm = AuBrPerm_RR;
else if (!bindex && !(sb_flags & MS_RDONLY))
add->perm = AuBrPerm_RW;
}
opt->type = Opt_add;
goto out;
}
pr_err("lookup failed %s (%d)\n", add->pathname, err);
err = -EINVAL;
out:
return err;
}
static int au_opts_parse_del(struct au_opt_del *del, substring_t args[])
{
int err;
del->pathname = args[0].from;
AuDbg("del path %s\n", del->pathname);
err = vfsub_kern_path(del->pathname, lkup_dirflags, &del->h_path);
if (unlikely(err))
pr_err("lookup failed %s (%d)\n", del->pathname, err);
return err;
}
static int noinline_for_stack
au_opts_parse_xino_itrunc_path(struct super_block *sb,
struct au_opt_xino_itrunc *xino_itrunc,
substring_t args[])
{
int err;
aufs_bindex_t bend, bindex;
struct path path;
struct dentry *root;
err = vfsub_kern_path(args[0].from, lkup_dirflags, &path);
if (unlikely(err)) {
pr_err("lookup failed %s (%d)\n", args[0].from, err);
goto out;
}
xino_itrunc->bindex = -1;
root = sb->s_root;
aufs_read_lock(root, AuLock_FLUSH);
bend = au_sbend(sb);
for (bindex = 0; bindex <= bend; bindex++) {
if (au_h_dptr(root, bindex) == path.dentry) {
xino_itrunc->bindex = bindex;
break;
}
}
aufs_read_unlock(root, !AuLock_IR);
path_put(&path);
if (unlikely(xino_itrunc->bindex < 0)) {
pr_err("no such branch %s\n", args[0].from);
err = -EINVAL;
}
out:
return err;
}
static
struct dentry *decode_by_path(struct super_block *sb, aufs_bindex_t bindex,
ino_t ino, __u32 *fh, int fh_len,
struct au_nfsd_si_lock *nsi_lock)
{
struct dentry *dentry, *h_parent, *root;
struct super_block *h_sb;
char *pathname, *p;
struct vfsmount *h_mnt;
struct au_branch *br;
int err;
struct path path;
br = au_sbr(sb, bindex);
/* au_br_get(br); */
h_mnt = br->br_mnt;
h_sb = h_mnt->mnt_sb;
/* todo: call lower fh_to_dentry()? fh_to_parent()? */
h_parent = exportfs_decode_fh(h_mnt, (void *)(fh + Fh_tail),
fh_len - Fh_tail, fh[Fh_h_type],
h_acceptable, /*context*/NULL);
dentry = h_parent;
if (unlikely(!h_parent || IS_ERR(h_parent))) {
AuWarn1("%s decode_fh failed, %ld\n",
au_sbtype(h_sb), PTR_ERR(h_parent));
goto out;
}
dentry = NULL;
if (unlikely(au_test_anon(h_parent))) {
AuWarn1("%s decode_fh returned a disconnected dentry\n",
au_sbtype(h_sb));
goto out_h_parent;
}
dentry = ERR_PTR(-ENOMEM);
pathname = (void *)__get_free_page(GFP_NOFS);
if (unlikely(!pathname))
goto out_h_parent;
root = sb->s_root;
path.mnt = h_mnt;
di_read_lock_parent(root, !AuLock_IR);
path.dentry = au_h_dptr(root, bindex);
di_read_unlock(root, !AuLock_IR);
p = au_build_path(h_parent, &path, pathname, PAGE_SIZE, sb);
dentry = (void *)p;
if (IS_ERR(p))
goto out_pathname;
si_read_unlock(sb);
err = vfsub_kern_path(p, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
dentry = ERR_PTR(err);
if (unlikely(err))
goto out_relock;
dentry = ERR_PTR(-ENOENT);
AuDebugOn(au_test_anon(path.dentry));
if (unlikely(!path.dentry->d_inode))
goto out_path;
if (ino != path.dentry->d_inode->i_ino)
dentry = au_lkup_by_ino(&path, ino, /*nsi_lock*/NULL);
else
dentry = dget(path.dentry);
out_path:
path_put(&path);
out_relock:
if (unlikely(si_nfsd_read_lock(sb, nsi_lock) < 0))
if (!IS_ERR(dentry)) {
dput(dentry);
dentry = ERR_PTR(-ESTALE);
}
out_pathname:
free_page((unsigned long)pathname);
out_h_parent:
dput(h_parent);
out:
/* au_br_put(br); */
AuTraceErrPtr(dentry);
return dentry;
}
