1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * export.c 4 * 5 * Functions to facilitate NFS exporting 6 * 7 * Copyright (C) 2002, 2005 Oracle. All rights reserved. 8 */ 9 10 #include <linux/fs.h> 11 #include <linux/types.h> 12 13 #include <cluster/masklog.h> 14 15 #include "ocfs2.h" 16 17 #include "alloc.h" 18 #include "dir.h" 19 #include "dlmglue.h" 20 #include "dcache.h" 21 #include "export.h" 22 #include "inode.h" 23 24 #include "buffer_head_io.h" 25 #include "suballoc.h" 26 #include "ocfs2_trace.h" 27 28 struct ocfs2_inode_handle 29 { 30 u64 ih_blkno; 31 u32 ih_generation; 32 }; 33 34 static struct dentry *ocfs2_get_dentry(struct super_block *sb, 35 struct ocfs2_inode_handle *handle) 36 { 37 struct inode *inode; 38 struct ocfs2_super *osb = OCFS2_SB(sb); 39 u64 blkno = handle->ih_blkno; 40 int status, set; 41 struct dentry *result; 42 43 trace_ocfs2_get_dentry_begin(sb, handle, (unsigned long long)blkno); 44 45 if (blkno == 0) { 46 result = ERR_PTR(-ESTALE); 47 goto bail; 48 } 49 50 inode = ocfs2_ilookup(sb, blkno); 51 /* 52 * If the inode exists in memory, we only need to check it's 53 * generation number 54 */ 55 if (inode) 56 goto check_gen; 57 58 /* 59 * This will synchronize us against ocfs2_delete_inode() on 60 * all nodes 61 */ 62 status = ocfs2_nfs_sync_lock(osb, 1); 63 if (status < 0) { 64 mlog(ML_ERROR, "getting nfs sync lock(EX) failed %d\n", status); 65 goto check_err; 66 } 67 68 status = ocfs2_test_inode_bit(osb, blkno, &set); 69 if (status < 0) { 70 if (status == -EINVAL) { 71 /* 72 * The blkno NFS gave us doesn't even show up 73 * as an inode, we return -ESTALE to be 74 * nice 75 */ 76 status = -ESTALE; 77 } else if (status != -ESTALE) { 78 mlog(ML_ERROR, "test inode bit failed %d\n", status); 79 } 80 goto unlock_nfs_sync; 81 } 82 83 trace_ocfs2_get_dentry_test_bit(status, set); 84 /* If the inode allocator bit is clear, this inode must be stale */ 85 if (!set) { 86 status = -ESTALE; 87 goto unlock_nfs_sync; 88 } 89 90 inode = ocfs2_iget(osb, blkno, 0, 0); 91 92 unlock_nfs_sync: 93 ocfs2_nfs_sync_unlock(osb, 1); 94 95 check_err: 96 if (status < 0) { 97 if (status == -ESTALE) { 98 trace_ocfs2_get_dentry_stale((unsigned long long)blkno, 99 handle->ih_generation); 100 } 101 result = ERR_PTR(status); 102 goto bail; 103 } 104 105 if (IS_ERR(inode)) { 106 mlog_errno(PTR_ERR(inode)); 107 result = ERR_CAST(inode); 108 goto bail; 109 } 110 111 check_gen: 112 if (handle->ih_generation != inode->i_generation) { 113 trace_ocfs2_get_dentry_generation((unsigned long long)blkno, 114 handle->ih_generation, 115 inode->i_generation); 116 iput(inode); 117 result = ERR_PTR(-ESTALE); 118 goto bail; 119 } 120 121 result = d_obtain_alias(inode); 122 if (IS_ERR(result)) 123 mlog_errno(PTR_ERR(result)); 124 125 bail: 126 trace_ocfs2_get_dentry_end(result); 127 return result; 128 } 129 130 static struct dentry *ocfs2_get_parent(struct dentry *child) 131 { 132 int status; 133 u64 blkno; 134 struct dentry *parent; 135 struct inode *dir = d_inode(child); 136 int set; 137 138 trace_ocfs2_get_parent(child, child->d_name.len, child->d_name.name, 139 (unsigned long long)OCFS2_I(dir)->ip_blkno); 140 141 status = ocfs2_nfs_sync_lock(OCFS2_SB(dir->i_sb), 1); 142 if (status < 0) { 143 mlog(ML_ERROR, "getting nfs sync lock(EX) failed %d\n", status); 144 parent = ERR_PTR(status); 145 goto bail; 146 } 147 148 status = ocfs2_inode_lock(dir, NULL, 0); 149 if (status < 0) { 150 if (status != -ENOENT) 151 mlog_errno(status); 152 parent = ERR_PTR(status); 153 goto unlock_nfs_sync; 154 } 155 156 status = ocfs2_lookup_ino_from_name(dir, "..", 2, &blkno); 157 if (status < 0) { 158 parent = ERR_PTR(-ENOENT); 159 goto bail_unlock; 160 } 161 162 status = ocfs2_test_inode_bit(OCFS2_SB(dir->i_sb), blkno, &set); 163 if (status < 0) { 164 if (status == -EINVAL) { 165 status = -ESTALE; 166 } else if (status != -ESTALE) { 167 mlog(ML_ERROR, "test inode bit failed %d\n", status); 168 } 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)); 181 182 bail_unlock: 183 ocfs2_inode_unlock(dir, 0); 184 185 unlock_nfs_sync: 186 ocfs2_nfs_sync_unlock(OCFS2_SB(dir->i_sb), 1); 187 188 bail: 189 trace_ocfs2_get_parent_end(parent); 190 191 return parent; 192 } 193 194 static 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; 246 247 bail: 248 trace_ocfs2_encode_fh_type(type); 249 return type; 250 } 251 252 static 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((__force __le32)fid->raw[0]) << 32; 261 handle.ih_blkno |= (u64)le32_to_cpu((__force __le32)fid->raw[1]); 262 handle.ih_generation = le32_to_cpu((__force __le32)fid->raw[2]); 263 return ocfs2_get_dentry(sb, &handle); 264 } 265 266 static 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((__force __le32)fid->raw[3]) << 32; 275 parent.ih_blkno |= (u64)le32_to_cpu((__force __le32)fid->raw[4]); 276 parent.ih_generation = le32_to_cpu((__force __le32)fid->raw[5]); 277 return ocfs2_get_dentry(sb, &parent); 278 } 279 280 const 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