1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/ceph/ceph_debug.h> 3 4 #include <linux/exportfs.h> 5 #include <linux/slab.h> 6 #include <asm/unaligned.h> 7 8 #include "super.h" 9 #include "mds_client.h" 10 11 /* 12 * Basic fh 13 */ 14 struct ceph_nfs_fh { 15 u64 ino; 16 } __attribute__ ((packed)); 17 18 /* 19 * Larger fh that includes parent ino. 20 */ 21 struct ceph_nfs_confh { 22 u64 ino, parent_ino; 23 } __attribute__ ((packed)); 24 25 static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, 26 struct inode *parent_inode) 27 { 28 int type; 29 struct ceph_nfs_fh *fh = (void *)rawfh; 30 struct ceph_nfs_confh *cfh = (void *)rawfh; 31 int connected_handle_length = sizeof(*cfh)/4; 32 int handle_length = sizeof(*fh)/4; 33 34 /* don't re-export snaps */ 35 if (ceph_snap(inode) != CEPH_NOSNAP) 36 return -EINVAL; 37 38 if (parent_inode && (*max_len < connected_handle_length)) { 39 *max_len = connected_handle_length; 40 return FILEID_INVALID; 41 } else if (*max_len < handle_length) { 42 *max_len = handle_length; 43 return FILEID_INVALID; 44 } 45 46 if (parent_inode) { 47 dout("encode_fh %llx with parent %llx\n", 48 ceph_ino(inode), ceph_ino(parent_inode)); 49 cfh->ino = ceph_ino(inode); 50 cfh->parent_ino = ceph_ino(parent_inode); 51 *max_len = connected_handle_length; 52 type = FILEID_INO32_GEN_PARENT; 53 } else { 54 dout("encode_fh %llx\n", ceph_ino(inode)); 55 fh->ino = ceph_ino(inode); 56 *max_len = handle_length; 57 type = FILEID_INO32_GEN; 58 } 59 return type; 60 } 61 62 static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) 63 { 64 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; 65 struct inode *inode; 66 struct ceph_vino vino; 67 int err; 68 69 vino.ino = ino; 70 vino.snap = CEPH_NOSNAP; 71 inode = ceph_find_inode(sb, vino); 72 if (!inode) { 73 struct ceph_mds_request *req; 74 int mask; 75 76 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO, 77 USE_ANY_MDS); 78 if (IS_ERR(req)) 79 return ERR_CAST(req); 80 81 mask = CEPH_STAT_CAP_INODE; 82 if (ceph_security_xattr_wanted(d_inode(sb->s_root))) 83 mask |= CEPH_CAP_XATTR_SHARED; 84 req->r_args.getattr.mask = cpu_to_le32(mask); 85 86 req->r_ino1 = vino; 87 req->r_num_caps = 1; 88 err = ceph_mdsc_do_request(mdsc, NULL, req); 89 inode = req->r_target_inode; 90 if (inode) 91 ihold(inode); 92 ceph_mdsc_put_request(req); 93 if (!inode) 94 return ERR_PTR(-ESTALE); 95 if (inode->i_nlink == 0) { 96 iput(inode); 97 return ERR_PTR(-ESTALE); 98 } 99 } 100 101 return d_obtain_alias(inode); 102 } 103 104 /* 105 * convert regular fh to dentry 106 */ 107 static struct dentry *ceph_fh_to_dentry(struct super_block *sb, 108 struct fid *fid, 109 int fh_len, int fh_type) 110 { 111 struct ceph_nfs_fh *fh = (void *)fid->raw; 112 113 if (fh_type != FILEID_INO32_GEN && 114 fh_type != FILEID_INO32_GEN_PARENT) 115 return NULL; 116 if (fh_len < sizeof(*fh) / 4) 117 return NULL; 118 119 dout("fh_to_dentry %llx\n", fh->ino); 120 return __fh_to_dentry(sb, fh->ino); 121 } 122 123 static struct dentry *__get_parent(struct super_block *sb, 124 struct dentry *child, u64 ino) 125 { 126 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; 127 struct ceph_mds_request *req; 128 struct inode *inode; 129 int mask; 130 int err; 131 132 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT, 133 USE_ANY_MDS); 134 if (IS_ERR(req)) 135 return ERR_CAST(req); 136 137 if (child) { 138 req->r_inode = d_inode(child); 139 ihold(d_inode(child)); 140 } else { 141 req->r_ino1 = (struct ceph_vino) { 142 .ino = ino, 143 .snap = CEPH_NOSNAP, 144 }; 145 } 146 147 mask = CEPH_STAT_CAP_INODE; 148 if (ceph_security_xattr_wanted(d_inode(sb->s_root))) 149 mask |= CEPH_CAP_XATTR_SHARED; 150 req->r_args.getattr.mask = cpu_to_le32(mask); 151 152 req->r_num_caps = 1; 153 err = ceph_mdsc_do_request(mdsc, NULL, req); 154 inode = req->r_target_inode; 155 if (inode) 156 ihold(inode); 157 ceph_mdsc_put_request(req); 158 if (!inode) 159 return ERR_PTR(-ENOENT); 160 161 return d_obtain_alias(inode); 162 } 163 164 static struct dentry *ceph_get_parent(struct dentry *child) 165 { 166 /* don't re-export snaps */ 167 if (ceph_snap(d_inode(child)) != CEPH_NOSNAP) 168 return ERR_PTR(-EINVAL); 169 170 dout("get_parent %p ino %llx.%llx\n", 171 child, ceph_vinop(d_inode(child))); 172 return __get_parent(child->d_sb, child, 0); 173 } 174 175 /* 176 * convert regular fh to parent 177 */ 178 static struct dentry *ceph_fh_to_parent(struct super_block *sb, 179 struct fid *fid, 180 int fh_len, int fh_type) 181 { 182 struct ceph_nfs_confh *cfh = (void *)fid->raw; 183 struct dentry *dentry; 184 185 if (fh_type != FILEID_INO32_GEN_PARENT) 186 return NULL; 187 if (fh_len < sizeof(*cfh) / 4) 188 return NULL; 189 190 dout("fh_to_parent %llx\n", cfh->parent_ino); 191 dentry = __get_parent(sb, NULL, cfh->ino); 192 if (unlikely(dentry == ERR_PTR(-ENOENT))) 193 dentry = __fh_to_dentry(sb, cfh->parent_ino); 194 return dentry; 195 } 196 197 static int ceph_get_name(struct dentry *parent, char *name, 198 struct dentry *child) 199 { 200 struct ceph_mds_client *mdsc; 201 struct ceph_mds_request *req; 202 int err; 203 204 mdsc = ceph_inode_to_client(d_inode(child))->mdsc; 205 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME, 206 USE_ANY_MDS); 207 if (IS_ERR(req)) 208 return PTR_ERR(req); 209 210 inode_lock(d_inode(parent)); 211 212 req->r_inode = d_inode(child); 213 ihold(d_inode(child)); 214 req->r_ino2 = ceph_vino(d_inode(parent)); 215 req->r_parent = d_inode(parent); 216 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); 217 req->r_num_caps = 2; 218 err = ceph_mdsc_do_request(mdsc, NULL, req); 219 220 inode_unlock(d_inode(parent)); 221 222 if (!err) { 223 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; 224 memcpy(name, rinfo->dname, rinfo->dname_len); 225 name[rinfo->dname_len] = 0; 226 dout("get_name %p ino %llx.%llx name %s\n", 227 child, ceph_vinop(d_inode(child)), name); 228 } else { 229 dout("get_name %p ino %llx.%llx err %d\n", 230 child, ceph_vinop(d_inode(child)), err); 231 } 232 233 ceph_mdsc_put_request(req); 234 return err; 235 } 236 237 const struct export_operations ceph_export_ops = { 238 .encode_fh = ceph_encode_fh, 239 .fh_to_dentry = ceph_fh_to_dentry, 240 .fh_to_parent = ceph_fh_to_parent, 241 .get_parent = ceph_get_parent, 242 .get_name = ceph_get_name, 243 }; 244