/* -*- mode: c; c-basic-offset: 8; -*- * vim: noexpandtab sw=8 ts=8 sts=0: * * export.c * * Functions to facilitate NFS exporting * * Copyright (C) 2002, 2005 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #include <linux/fs.h> #include <linux/types.h> #define MLOG_MASK_PREFIX ML_EXPORT #include <cluster/masklog.h> #include "ocfs2.h" #include "dir.h" #include "dlmglue.h" #include "dcache.h" #include "export.h" #include "inode.h" #include "buffer_head_io.h" struct ocfs2_inode_handle { u64 ih_blkno; u32 ih_generation; }; static struct dentry *ocfs2_get_dentry(struct super_block *sb, void *vobjp) { struct ocfs2_inode_handle *handle = vobjp; struct inode *inode; struct dentry *result; mlog_entry("(0x%p, 0x%p)\n", sb, handle); if (handle->ih_blkno == 0) { mlog_errno(-ESTALE); return ERR_PTR(-ESTALE); } inode = ocfs2_iget(OCFS2_SB(sb), handle->ih_blkno, 0); if (IS_ERR(inode)) return (void *)inode; if (handle->ih_generation != inode->i_generation) { iput(inode); return ERR_PTR(-ESTALE); } result = d_alloc_anon(inode); if (!result) { iput(inode); mlog_errno(-ENOMEM); return ERR_PTR(-ENOMEM); } result->d_op = &ocfs2_dentry_ops; mlog_exit_ptr(result); return result; } static struct dentry *ocfs2_get_parent(struct dentry *child) { int status; u64 blkno; struct dentry *parent; struct inode *inode; struct inode *dir = child->d_inode; mlog_entry("(0x%p, '%.*s')\n", child, child->d_name.len, child->d_name.name); mlog(0, "find parent of directory %llu\n", (unsigned long long)OCFS2_I(dir)->ip_blkno); status = ocfs2_meta_lock(dir, NULL, 0); if (status < 0) { if (status != -ENOENT) mlog_errno(status); parent = ERR_PTR(status); goto bail; } status = ocfs2_lookup_ino_from_name(dir, "..", 2, &blkno); if (status < 0) { parent = ERR_PTR(-ENOENT); goto bail_unlock; } inode = ocfs2_iget(OCFS2_SB(dir->i_sb), blkno, 0); if (IS_ERR(inode)) { mlog(ML_ERROR, "Unable to create inode %llu\n", (unsigned long long)blkno); parent = ERR_PTR(-EACCES); goto bail_unlock; } parent = d_alloc_anon(inode); if (!parent) { iput(inode); parent = ERR_PTR(-ENOMEM); } parent->d_op = &ocfs2_dentry_ops; bail_unlock: ocfs2_meta_unlock(dir, 0); bail: mlog_exit_ptr(parent); return parent; } static int ocfs2_encode_fh(struct dentry *dentry, u32 *fh_in, int *max_len, int connectable) { struct inode *inode = dentry->d_inode; int len = *max_len; int type = 1; u64 blkno; u32 generation; __le32 *fh = (__force __le32 *) fh_in; mlog_entry("(0x%p, '%.*s', 0x%p, %d, %d)\n", dentry, dentry->d_name.len, dentry->d_name.name, fh, len, connectable); if (len < 3 || (connectable && len < 6)) { mlog(ML_ERROR, "fh buffer is too small for encoding\n"); type = 255; goto bail; } blkno = OCFS2_I(inode)->ip_blkno; generation = inode->i_generation; mlog(0, "Encoding fh: blkno: %llu, generation: %u\n", (unsigned long long)blkno, generation); len = 3; fh[0] = cpu_to_le32((u32)(blkno >> 32)); fh[1] = cpu_to_le32((u32)(blkno & 0xffffffff)); fh[2] = cpu_to_le32(generation); if (connectable && !S_ISDIR(inode->i_mode)) { struct inode *parent; spin_lock(&dentry->d_lock); parent = dentry->d_parent->d_inode; blkno = OCFS2_I(parent)->ip_blkno; generation = parent->i_generation; fh[3] = cpu_to_le32((u32)(blkno >> 32)); fh[4] = cpu_to_le32((u32)(blkno & 0xffffffff)); fh[5] = cpu_to_le32(generation); spin_unlock(&dentry->d_lock); len = 6; type = 2; mlog(0, "Encoding parent: blkno: %llu, generation: %u\n", (unsigned long long)blkno, generation); } *max_len = len; bail: mlog_exit(type); return type; } static struct dentry *ocfs2_decode_fh(struct super_block *sb, u32 *fh_in, int fh_len, int fileid_type, int (*acceptable)(void *context, struct dentry *de), void *context) { struct ocfs2_inode_handle handle, parent; struct dentry *ret = NULL; __le32 *fh = (__force __le32 *) fh_in; mlog_entry("(0x%p, 0x%p, %d, %d, 0x%p, 0x%p)\n", sb, fh, fh_len, fileid_type, acceptable, context); if (fh_len < 3 || fileid_type > 2) goto bail; if (fileid_type == 2) { if (fh_len < 6) goto bail; parent.ih_blkno = (u64)le32_to_cpu(fh[3]) << 32; parent.ih_blkno |= (u64)le32_to_cpu(fh[4]); parent.ih_generation = le32_to_cpu(fh[5]); mlog(0, "Decoding parent: blkno: %llu, generation: %u\n", (unsigned long long)parent.ih_blkno, parent.ih_generation); } handle.ih_blkno = (u64)le32_to_cpu(fh[0]) << 32; handle.ih_blkno |= (u64)le32_to_cpu(fh[1]); handle.ih_generation = le32_to_cpu(fh[2]); mlog(0, "Encoding fh: blkno: %llu, generation: %u\n", (unsigned long long)handle.ih_blkno, handle.ih_generation); ret = ocfs2_export_ops.find_exported_dentry(sb, &handle, &parent, acceptable, context); bail: mlog_exit_ptr(ret); return ret; } struct export_operations ocfs2_export_ops = { .decode_fh = ocfs2_decode_fh, .encode_fh = ocfs2_encode_fh, .get_parent = ocfs2_get_parent, .get_dentry = ocfs2_get_dentry, };