1// SPDX-License-Identifier: GPL-2.0-or-later 2/* -*- mode: c; c-basic-offset: 8; -*- 3 * vim: noexpandtab sw=8 ts=8 sts=0: 4 * 5 * export.c 6 * 7 * Functions to facilitate NFS exporting 8 * 9 * Copyright (C) 2002, 2005 Oracle. All rights reserved. 10 */ 11 12#include <linux/fs.h> 13#include <linux/types.h> 14 15#include <cluster/masklog.h> 16 17#include "ocfs2.h" 18 19#include "alloc.h" 20#include "dir.h" 21#include "dlmglue.h" 22#include "dcache.h" 23#include "export.h" 24#include "inode.h" 25 26#include "buffer_head_io.h" 27#include "suballoc.h" 28#include "ocfs2_trace.h" 29 30struct ocfs2_inode_handle 31{ 32 u64 ih_blkno; 33 u32 ih_generation; 34}; 35 36static struct dentry *ocfs2_get_dentry(struct super_block *sb, 37 struct ocfs2_inode_handle *handle) 38{ 39 struct inode *inode; 40 struct ocfs2_super *osb = OCFS2_SB(sb); 41 u64 blkno = handle->ih_blkno; 42 int status, set; 43 struct dentry *result; 44 45 trace_ocfs2_get_dentry_begin(sb, handle, (unsigned long long)blkno); 46 47 if (blkno == 0) { 48 result = ERR_PTR(-ESTALE); 49 goto bail; 50 } 51 52 inode = ocfs2_ilookup(sb, blkno); 53 /* 54 * If the inode exists in memory, we only need to check it's 55 * generation number 56 */ 57 if (inode) 58 goto check_gen; 59 60 /* 61 * This will synchronize us against ocfs2_delete_inode() on 62 * all nodes 63 */ 64 status = ocfs2_nfs_sync_lock(osb, 1); 65 if (status < 0) { 66 mlog(ML_ERROR, "getting nfs sync lock(EX) failed %d\n", status); 67 goto check_err; 68 } 69 70 status = ocfs2_test_inode_bit(osb, blkno, &set); 71 if (status < 0) { 72 if (status == -EINVAL) { 73 /* 74 * The blkno NFS gave us doesn't even show up 75 * as an inode, we return -ESTALE to be 76 * nice 77 */ 78 status = -ESTALE; 79 } else 80 mlog(ML_ERROR, "test inode bit failed %d\n", status); 81 goto unlock_nfs_sync; 82 } 83 84 trace_ocfs2_get_dentry_test_bit(status, set); 85 /* If the inode allocator bit is clear, this inode must be stale */ 86 if (!set) { 87 status = -ESTALE; 88 goto unlock_nfs_sync; 89 } 90 91 inode = ocfs2_iget(osb, blkno, 0, 0); 92 93unlock_nfs_sync: 94 ocfs2_nfs_sync_unlock(osb, 1); 95 96check_err: 97 if (status < 0) { 98 if (status == -ESTALE) { 99 trace_ocfs2_get_dentry_stale((unsigned long long)blkno, 100 handle->ih_generation); 101 } 102 result = ERR_PTR(status); 103 goto bail; 104 } 105 106 if (IS_ERR(inode)) { 107 mlog_errno(PTR_ERR(inode)); 108 result = ERR_CAST(inode); 109 goto bail; 110 } 111 112check_gen: 113 if (handle->ih_generation != inode->i_generation) { 114 trace_ocfs2_get_dentry_generation((unsigned long long)blkno, 115 handle->ih_generation, 116 inode->i_generation); 117 iput(inode); 118 result = ERR_PTR(-ESTALE); 119 goto bail; 120 } 121 122 result = d_obtain_alias(inode); 123 if (IS_ERR(result)) 124 mlog_errno(PTR_ERR(result)); 125 126bail: 127 trace_ocfs2_get_dentry_end(result); 128 return result; 129} 130 131static struct dentry *ocfs2_get_parent(struct dentry *child) 132{ 133 int status; 134 u64 blkno; 135 struct dentry *parent; 136 struct inode *dir = d_inode(child); 137 int set; 138 139 trace_ocfs2_get_parent(child, child->d_name.len, child->d_name.name, 140 (unsigned long long)OCFS2_I(dir)->ip_blkno); 141 142 status = ocfs2_nfs_sync_lock(OCFS2_SB(dir->i_sb), 1); 143 if (status < 0) { 144 mlog(ML_ERROR, "getting nfs sync lock(EX) failed %d\n", status); 145 parent = ERR_PTR(status); 146 goto bail; 147 } 148 149 status = ocfs2_inode_lock(dir, NULL, 0); 150 if (status < 0) { 151 if (status != -ENOENT) 152 mlog_errno(status); 153 parent = ERR_PTR(status); 154 goto unlock_nfs_sync; 155 } 156 157 status = ocfs2_lookup_ino_from_name(dir, "..", 2, &blkno); 158 if (status < 0) { 159 parent = ERR_PTR(-ENOENT); 160 goto bail_unlock; 161 } 162 163 status = ocfs2_test_inode_bit(OCFS2_SB(dir->i_sb), blkno, &set); 164 if (status < 0) { 165 if (status == -EINVAL) { 166 status = -ESTALE; 167 } else 168 mlog(ML_ERROR, "test inode bit failed %d\n", status); 169 parent = ERR_PTR(status); 170 goto bail_unlock; 171 } 172 173 trace_ocfs2_get_dentry_test_bit(status, set); 174 if (!set) { 175 status = -ESTALE; 176 parent = ERR_PTR(status); 177 goto bail_unlock; 178 } 179 180 parent = d_obtain_alias(ocfs2_iget(OCFS2_SB(dir->i_sb), blkno, 0, 0)); 181 182bail_unlock: 183 ocfs2_inode_unlock(dir, 0); 184 185unlock_nfs_sync: 186 ocfs2_nfs_sync_unlock(OCFS2_SB(dir->i_sb), 1); 187 188bail: 189 trace_ocfs2_get_parent_end(parent); 190 191 return parent; 192} 193 194static int ocfs2_encode_fh(struct inode *inode, u32 *fh_in, int *max_len, 195 struct inode *parent) 196{ 197 int len = *max_len; 198 int type = 1; 199 u64 blkno; 200 u32 generation; 201 __le32 *fh = (__force __le32 *) fh_in; 202 203#ifdef TRACE_HOOKS_ARE_NOT_BRAINDEAD_IN_YOUR_OPINION 204#error "You go ahead and fix that mess, then. Somehow" 205 trace_ocfs2_encode_fh_begin(dentry, dentry->d_name.len, 206 dentry->d_name.name, 207 fh, len, connectable); 208#endif 209 210 if (parent && (len < 6)) { 211 *max_len = 6; 212 type = FILEID_INVALID; 213 goto bail; 214 } else if (len < 3) { 215 *max_len = 3; 216 type = FILEID_INVALID; 217 goto bail; 218 } 219 220 blkno = OCFS2_I(inode)->ip_blkno; 221 generation = inode->i_generation; 222 223 trace_ocfs2_encode_fh_self((unsigned long long)blkno, generation); 224 225 len = 3; 226 fh[0] = cpu_to_le32((u32)(blkno >> 32)); 227 fh[1] = cpu_to_le32((u32)(blkno & 0xffffffff)); 228 fh[2] = cpu_to_le32(generation); 229 230 if (parent) { 231 blkno = OCFS2_I(parent)->ip_blkno; 232 generation = parent->i_generation; 233 234 fh[3] = cpu_to_le32((u32)(blkno >> 32)); 235 fh[4] = cpu_to_le32((u32)(blkno & 0xffffffff)); 236 fh[5] = cpu_to_le32(generation); 237 238 len = 6; 239 type = 2; 240 241 trace_ocfs2_encode_fh_parent((unsigned long long)blkno, 242 generation); 243 } 244 245 *max_len = len; 246 247bail: 248 trace_ocfs2_encode_fh_type(type); 249 return type; 250} 251 252static struct dentry *ocfs2_fh_to_dentry(struct super_block *sb, 253 struct fid *fid, int fh_len, int fh_type) 254{ 255 struct ocfs2_inode_handle handle; 256 257 if (fh_len < 3 || fh_type > 2) 258 return NULL; 259 260 handle.ih_blkno = (u64)le32_to_cpu(fid->raw[0]) << 32; 261 handle.ih_blkno |= (u64)le32_to_cpu(fid->raw[1]); 262 handle.ih_generation = le32_to_cpu(fid->raw[2]); 263 return ocfs2_get_dentry(sb, &handle); 264} 265 266static struct dentry *ocfs2_fh_to_parent(struct super_block *sb, 267 struct fid *fid, int fh_len, int fh_type) 268{ 269 struct ocfs2_inode_handle parent; 270 271 if (fh_type != 2 || fh_len < 6) 272 return NULL; 273 274 parent.ih_blkno = (u64)le32_to_cpu(fid->raw[3]) << 32; 275 parent.ih_blkno |= (u64)le32_to_cpu(fid->raw[4]); 276 parent.ih_generation = le32_to_cpu(fid->raw[5]); 277 return ocfs2_get_dentry(sb, &parent); 278} 279 280const struct export_operations ocfs2_export_ops = { 281 .encode_fh = ocfs2_encode_fh, 282 .fh_to_dentry = ocfs2_fh_to_dentry, 283 .fh_to_parent = ocfs2_fh_to_parent, 284 .get_parent = ocfs2_get_parent, 285}; 286