+struct fuse_inode_handle {
+ u64 nodeid;
+ u32 generation;
+};
+
+static struct dentry *fuse_get_dentry(struct super_block *sb,
+ struct fuse_inode_handle *handle)
+{
+ struct fuse_conn *fc = get_fuse_conn_super(sb);
+ struct inode *inode;
+ struct dentry *entry;
+ int err = -ESTALE;
+
+ if (handle->nodeid == 0)
+ goto out_err;
+
+ inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
+ if (!inode) {
+ struct fuse_entry_out outarg;
+ struct qstr name;
+
+ if (!fc->export_support)
+ goto out_err;
+
+ name.len = 1;
+ name.name = ".";
+ err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
+ &inode);
+ if (err && err != -ENOENT)
+ goto out_err;
+ if (err || !inode) {
+ err = -ESTALE;
+ goto out_err;
+ }
+ err = -EIO;
+ if (get_node_id(inode) != handle->nodeid)
+ goto out_iput;
+ }
+ err = -ESTALE;
+ if (inode->i_generation != handle->generation)
+ goto out_iput;
+
+ entry = d_obtain_alias(inode);
+ if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) {
+ entry->d_op = &fuse_dentry_operations;
+ fuse_invalidate_entry_cache(entry);
+ }
+
+ return entry;
+
+ out_iput:
+ iput(inode);
+ out_err:
+ return ERR_PTR(err);
+}
+
+static int fuse_encode_fh(struct dentry *dentry, u32 *fh, int *max_len,
+ int connectable)
+{
+ struct inode *inode = dentry->d_inode;
+ bool encode_parent = connectable && !S_ISDIR(inode->i_mode);
+ int len = encode_parent ? 6 : 3;
+ u64 nodeid;
+ u32 generation;
+
+ if (*max_len < len)
+ return 255;
+
+ nodeid = get_fuse_inode(inode)->nodeid;
+ generation = inode->i_generation;
+
+ fh[0] = (u32)(nodeid >> 32);
+ fh[1] = (u32)(nodeid & 0xffffffff);
+ fh[2] = generation;
+
+ if (encode_parent) {
+ struct inode *parent;
+
+ spin_lock(&dentry->d_lock);
+ parent = dentry->d_parent->d_inode;
+ nodeid = get_fuse_inode(parent)->nodeid;
+ generation = parent->i_generation;
+ spin_unlock(&dentry->d_lock);
+
+ fh[3] = (u32)(nodeid >> 32);
+ fh[4] = (u32)(nodeid & 0xffffffff);
+ fh[5] = generation;
+ }
+
+ *max_len = len;
+ return encode_parent ? 0x82 : 0x81;
+}
+
+static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ struct fuse_inode_handle handle;
+
+ if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
+ return NULL;
+
+ handle.nodeid = (u64) fid->raw[0] << 32;
+ handle.nodeid |= (u64) fid->raw[1];
+ handle.generation = fid->raw[2];
+ return fuse_get_dentry(sb, &handle);
+}
+
+static struct dentry *fuse_fh_to_parent(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ struct fuse_inode_handle parent;
+
+ if (fh_type != 0x82 || fh_len < 6)
+ return NULL;
+
+ parent.nodeid = (u64) fid->raw[3] << 32;
+ parent.nodeid |= (u64) fid->raw[4];
+ parent.generation = fid->raw[5];
+ return fuse_get_dentry(sb, &parent);
+}
+
+static struct dentry *fuse_get_parent(struct dentry *child)
+{
+ struct inode *child_inode = child->d_inode;
+ struct fuse_conn *fc = get_fuse_conn(child_inode);
+ struct inode *inode;
+ struct dentry *parent;
+ struct fuse_entry_out outarg;
+ struct qstr name;
+ int err;
+
+ if (!fc->export_support)
+ return ERR_PTR(-ESTALE);
+
+ name.len = 2;
+ name.name = "..";
+ err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
+ &name, &outarg, &inode);
+ if (err) {
+ if (err == -ENOENT)
+ return ERR_PTR(-ESTALE);
+ return ERR_PTR(err);
+ }
+
+ parent = d_obtain_alias(inode);
+ if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) {
+ parent->d_op = &fuse_dentry_operations;
+ fuse_invalidate_entry_cache(parent);
+ }
+
+ return parent;
+}
+
+static const struct export_operations fuse_export_operations = {
+ .fh_to_dentry = fuse_fh_to_dentry,
+ .fh_to_parent = fuse_fh_to_parent,
+ .encode_fh = fuse_encode_fh,
+ .get_parent = fuse_get_parent,
+};
+
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff