static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
unsigned int flags)
{
int err;
struct fuse_entry_out outarg;
struct inode *inode;
struct dentry *newent;
struct fuse_conn *fc = get_fuse_conn(dir);
bool outarg_valid = true;
err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
&outarg, &inode);
if (err == -ENOENT) {
outarg_valid = false;
err = 0;
}
if (err)
goto out_err;
err = -EIO;
if (inode && get_node_id(inode) == FUSE_ROOT_ID)
goto out_iput;
if (inode && S_ISDIR(inode->i_mode)) {
mutex_lock(&fc->inst_mutex);
newent = fuse_d_add_directory(entry, inode);
mutex_unlock(&fc->inst_mutex);
err = PTR_ERR(newent);
if (IS_ERR(newent))
goto out_iput;
} else {
newent = d_splice_alias(inode, entry);
}
entry = newent ? newent : entry;
if (outarg_valid)
fuse_change_entry_timeout(entry, &outarg);
else
fuse_invalidate_entry_cache(entry);
fuse_advise_use_readdirplus(dir);
return newent;
out_iput:
iput(inode);
out_err:
return ERR_PTR(err);
}
static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
unsigned int flags)
{
int err;
struct fuse_entry_out outarg;
struct inode *inode;
struct dentry *newent;
bool outarg_valid = true;
bool locked;
locked = fuse_lock_inode(dir);
err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
&outarg, &inode);
fuse_unlock_inode(dir, locked);
if (err == -ENOENT) {
outarg_valid = false;
err = 0;
}
if (err)
goto out_err;
err = -EIO;
if (inode && get_node_id(inode) == FUSE_ROOT_ID)
goto out_iput;
newent = d_splice_alias(inode, entry);
err = PTR_ERR(newent);
if (IS_ERR(newent))
goto out_err;
entry = newent ? newent : entry;
if (outarg_valid)
fuse_change_entry_timeout(entry, &outarg);
else
fuse_invalidate_entry_cache(entry);
fuse_advise_use_readdirplus(dir);
return newent;
out_iput:
iput(inode);
out_err:
return ERR_PTR(err);
}
static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
struct nameidata *nd)
{
int err;
struct fuse_entry_out outarg;
struct inode *inode;
struct dentry *newent;
bool outarg_valid = true;
err = fuse_lookup_name(dir->i_sb, get_node_id(dir), &entry->d_name,
&outarg, &inode);
if (err == -ENOENT) {
outarg_valid = false;
err = 0;
}
if (err)
goto out_err;
err = -EIO;
if (inode && get_node_id(inode) == FUSE_ROOT_ID)
goto out_iput;
newent = fuse_materialise_dentry(entry, inode);
err = PTR_ERR(newent);
if (IS_ERR(newent))
goto out_err;
entry = newent ? newent : entry;
entry->d_op = &fuse_dentry_operations;
if (outarg_valid)
fuse_change_entry_timeout(entry, &outarg);
else
fuse_invalidate_entry_cache(entry);
fuse_advise_use_readdirplus(dir);
return newent;
out_iput:
iput(inode);
out_err:
return ERR_PTR(err);
}
/*
* Check whether the dentry is still valid
*
* If the entry validity timeout has expired and the dentry is
* positive, try to redo the lookup. If the lookup results in a
* different inode, then let the VFS invalidate the dentry and redo
* the lookup once more. If the lookup results in the same inode,
* then refresh the attributes, timeouts and mark the dentry valid.
*/
static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
{
struct inode *inode;
struct dentry *parent;
struct fuse_conn *fc;
int ret;
inode = ACCESS_ONCE(entry->d_inode);
if (inode && is_bad_inode(inode))
goto invalid;
else if (fuse_dentry_time(entry) < get_jiffies_64()) {
int err;
struct fuse_entry_out outarg;
struct fuse_req *req;
struct fuse_forget_link *forget;
u64 attr_version;
/* For negative dentries, always do a fresh lookup */
if (!inode)
goto invalid;
ret = -ECHILD;
if (flags & LOOKUP_RCU)
goto out;
fc = get_fuse_conn(inode);
req = fuse_get_req_nopages(fc);
ret = PTR_ERR(req);
if (IS_ERR(req))
goto out;
forget = fuse_alloc_forget();
if (!forget) {
fuse_put_request(fc, req);
ret = -ENOMEM;
goto out;
}
attr_version = fuse_get_attr_version(fc);
parent = dget_parent(entry);
fuse_lookup_init(fc, req, get_node_id(parent->d_inode),
&entry->d_name, &outarg);
fuse_request_send(fc, req);
dput(parent);
err = req->out.h.error;
fuse_put_request(fc, req);
/* Zero nodeid is same as -ENOENT */
if (!err && !outarg.nodeid)
err = -ENOENT;
if (!err) {
struct fuse_inode *fi = get_fuse_inode(inode);
if (outarg.nodeid != get_node_id(inode)) {
fuse_queue_forget(fc, forget, outarg.nodeid, 1);
goto invalid;
}
spin_lock(&fc->lock);
fi->nlookup++;
spin_unlock(&fc->lock);
}
kfree(forget);
if (err || (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
goto invalid;
fuse_change_attributes(inode, &outarg.attr,
entry_attr_timeout(&outarg),
attr_version);
fuse_change_entry_timeout(entry, &outarg);
} else if (inode) {
fc = get_fuse_conn(inode);
if (fc->readdirplus_auto) {
parent = dget_parent(entry);
fuse_advise_use_readdirplus(parent->d_inode);
dput(parent);
}
}
ret = 1;
out:
return ret;
invalid:
ret = 0;
if (check_submounts_and_drop(entry) != 0)
ret = 1;
goto out;
}
/*
* Check whether the dentry is still valid
*
* If the entry validity timeout has expired and the dentry is
* positive, try to redo the lookup. If the lookup results in a
* different inode, then let the VFS invalidate the dentry and redo
* the lookup once more. If the lookup results in the same inode,
* then refresh the attributes, timeouts and mark the dentry valid.
*/
static int fuse_dentry_revalidate(struct dentry *entry, unsigned int flags)
{
struct inode *inode;
struct dentry *parent;
struct fuse_conn *fc;
struct fuse_inode *fi;
int ret;
inode = d_inode_rcu(entry);
if (inode && is_bad_inode(inode))
goto invalid;
else if (time_before64(fuse_dentry_time(entry), get_jiffies_64()) ||
(flags & LOOKUP_REVAL)) {
struct fuse_entry_out outarg;
FUSE_ARGS(args);
struct fuse_forget_link *forget;
u64 attr_version;
/* For negative dentries, always do a fresh lookup */
if (!inode)
goto invalid;
ret = -ECHILD;
if (flags & LOOKUP_RCU)
goto out;
fc = get_fuse_conn(inode);
forget = fuse_alloc_forget();
ret = -ENOMEM;
if (!forget)
goto out;
attr_version = fuse_get_attr_version(fc);
parent = dget_parent(entry);
fuse_lookup_init(fc, &args, get_node_id(d_inode(parent)),
&entry->d_name, &outarg);
ret = fuse_simple_request(fc, &args);
dput(parent);
/* Zero nodeid is same as -ENOENT */
if (!ret && !outarg.nodeid)
ret = -ENOENT;
if (!ret) {
fi = get_fuse_inode(inode);
if (outarg.nodeid != get_node_id(inode)) {
fuse_queue_forget(fc, forget, outarg.nodeid, 1);
goto invalid;
}
spin_lock(&fc->lock);
fi->nlookup++;
spin_unlock(&fc->lock);
}
kfree(forget);
if (ret == -ENOMEM)
goto out;
if (ret || (outarg.attr.mode ^ inode->i_mode) & S_IFMT)
goto invalid;
forget_all_cached_acls(inode);
fuse_change_attributes(inode, &outarg.attr,
entry_attr_timeout(&outarg),
attr_version);
fuse_change_entry_timeout(entry, &outarg);
} else if (inode) {
fi = get_fuse_inode(inode);
if (flags & LOOKUP_RCU) {
if (test_bit(FUSE_I_INIT_RDPLUS, &fi->state))
return -ECHILD;
} else if (test_and_clear_bit(FUSE_I_INIT_RDPLUS, &fi->state)) {
parent = dget_parent(entry);
fuse_advise_use_readdirplus(d_inode(parent));
dput(parent);
}
}
ret = 1;
out:
return ret;
invalid:
ret = 0;
goto out;
}
