struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
{
kuid_t uid;
int any, access;
struct v9fs_session_info *v9ses;
v9ses = v9fs_dentry2v9ses(dentry);
access = v9ses->flags & V9FS_ACCESS_MASK;
switch (access) {
case V9FS_ACCESS_SINGLE:
case V9FS_ACCESS_USER:
case V9FS_ACCESS_CLIENT:
uid = current_fsuid();
any = 0;
break;
case V9FS_ACCESS_ANY:
uid = v9ses->uid;
any = 1;
break;
default:
uid = INVALID_UID;
any = 0;
break;
}
return v9fs_fid_lookup_with_uid(dentry, uid, any);
}
static struct p9_fid *v9fs_fid_clone_with_uid(struct dentry *dentry, kuid_t uid)
{
struct p9_fid *fid, *ret;
fid = v9fs_fid_lookup_with_uid(dentry, uid, 0);
if (IS_ERR(fid))
return fid;
ret = p9_client_walk(fid, 0, NULL, 1);
return ret;
}
struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
{
int err;
struct p9_fid *fid;
fid = clone_fid(v9fs_fid_lookup_with_uid(dentry, GLOBAL_ROOT_UID, 0));
if (IS_ERR(fid))
goto error_out;
/*
* writeback fid will only be used to write back the
* dirty pages. We always request for the open fid in read-write
* mode so that a partial page write which result in page
* read can work.
*/
err = p9_client_open(fid, O_RDWR);
if (err < 0) {
p9_client_clunk(fid);
fid = ERR_PTR(err);
goto error_out;
}
error_out:
return fid;
}
