1 #include <linux/ceph/ceph_debug.h> 2 3 #include <linux/exportfs.h> 4 #include <linux/slab.h> 5 #include <asm/unaligned.h> 6 7 #include "super.h" 8 #include "mds_client.h" 9 10 /* 11 * Basic fh 12 */ 13 struct ceph_nfs_fh { 14 u64 ino; 15 } __attribute__ ((packed)); 16 17 /* 18 * Larger fh that includes parent ino. 19 */ 20 struct ceph_nfs_confh { 21 u64 ino, parent_ino; 22 } __attribute__ ((packed)); 23 24 static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, 25 struct inode *parent_inode) 26 { 27 int type; 28 struct ceph_nfs_fh *fh = (void *)rawfh; 29 struct ceph_nfs_confh *cfh = (void *)rawfh; 30 int connected_handle_length = sizeof(*cfh)/4; 31 int handle_length = sizeof(*fh)/4; 32 33 /* don't re-export snaps */ 34 if (ceph_snap(inode) != CEPH_NOSNAP) 35 return -EINVAL; 36 37 if (parent_inode && (*max_len < connected_handle_length)) { 38 *max_len = connected_handle_length; 39 return FILEID_INVALID; 40 } else if (*max_len < handle_length) { 41 *max_len = handle_length; 42 return FILEID_INVALID; 43 } 44 45 if (parent_inode) { 46 dout("encode_fh %llx with parent %llx\n", 47 ceph_ino(inode), ceph_ino(parent_inode)); 48 cfh->ino = ceph_ino(inode); 49 cfh->parent_ino = ceph_ino(parent_inode); 50 *max_len = connected_handle_length; 51 type = FILEID_INO32_GEN_PARENT; 52 } else { 53 dout("encode_fh %llx\n", ceph_ino(inode)); 54 fh->ino = ceph_ino(inode); 55 *max_len = handle_length; 56 type = FILEID_INO32_GEN; 57 } 58 return type; 59 } 60 61 static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) 62 { 63 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; 64 struct inode *inode; 65 struct dentry *dentry; 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 75 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO, 76 USE_ANY_MDS); 77 if (IS_ERR(req)) 78 return ERR_CAST(req); 79 80 req->r_ino1 = vino; 81 req->r_num_caps = 1; 82 err = ceph_mdsc_do_request(mdsc, NULL, req); 83 inode = req->r_target_inode; 84 if (inode) 85 ihold(inode); 86 ceph_mdsc_put_request(req); 87 if (!inode) 88 return ERR_PTR(-ESTALE); 89 } 90 91 dentry = d_obtain_alias(inode); 92 if (IS_ERR(dentry)) { 93 iput(inode); 94 return dentry; 95 } 96 err = ceph_init_dentry(dentry); 97 if (err < 0) { 98 dput(dentry); 99 return ERR_PTR(err); 100 } 101 dout("__fh_to_dentry %llx %p dentry %p\n", ino, inode, dentry); 102 return dentry; 103 } 104 105 /* 106 * convert regular fh to dentry 107 */ 108 static struct dentry *ceph_fh_to_dentry(struct super_block *sb, 109 struct fid *fid, 110 int fh_len, int fh_type) 111 { 112 struct ceph_nfs_fh *fh = (void *)fid->raw; 113 114 if (fh_type != FILEID_INO32_GEN && 115 fh_type != FILEID_INO32_GEN_PARENT) 116 return NULL; 117 if (fh_len < sizeof(*fh) / 4) 118 return NULL; 119 120 dout("fh_to_dentry %llx\n", fh->ino); 121 return __fh_to_dentry(sb, fh->ino); 122 } 123 124 static struct dentry *__get_parent(struct super_block *sb, 125 struct dentry *child, u64 ino) 126 { 127 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; 128 struct ceph_mds_request *req; 129 struct inode *inode; 130 struct dentry *dentry; 131 int err; 132 133 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT, 134 USE_ANY_MDS); 135 if (IS_ERR(req)) 136 return ERR_CAST(req); 137 138 if (child) { 139 req->r_inode = child->d_inode; 140 ihold(child->d_inode); 141 } else { 142 req->r_ino1 = (struct ceph_vino) { 143 .ino = ino, 144 .snap = CEPH_NOSNAP, 145 }; 146 } 147 req->r_num_caps = 1; 148 err = ceph_mdsc_do_request(mdsc, NULL, req); 149 inode = req->r_target_inode; 150 if (inode) 151 ihold(inode); 152 ceph_mdsc_put_request(req); 153 if (!inode) 154 return ERR_PTR(-ENOENT); 155 156 dentry = d_obtain_alias(inode); 157 if (IS_ERR(dentry)) { 158 iput(inode); 159 return dentry; 160 } 161 err = ceph_init_dentry(dentry); 162 if (err < 0) { 163 dput(dentry); 164 return ERR_PTR(err); 165 } 166 dout("__get_parent ino %llx parent %p ino %llx.%llx\n", 167 child ? ceph_ino(child->d_inode) : ino, 168 dentry, ceph_vinop(inode)); 169 return dentry; 170 } 171 172 static struct dentry *ceph_get_parent(struct dentry *child) 173 { 174 /* don't re-export snaps */ 175 if (ceph_snap(child->d_inode) != CEPH_NOSNAP) 176 return ERR_PTR(-EINVAL); 177 178 dout("get_parent %p ino %llx.%llx\n", 179 child, ceph_vinop(child->d_inode)); 180 return __get_parent(child->d_sb, child, 0); 181 } 182 183 /* 184 * convert regular fh to parent 185 */ 186 static struct dentry *ceph_fh_to_parent(struct super_block *sb, 187 struct fid *fid, 188 int fh_len, int fh_type) 189 { 190 struct ceph_nfs_confh *cfh = (void *)fid->raw; 191 struct dentry *dentry; 192 193 if (fh_type != FILEID_INO32_GEN_PARENT) 194 return NULL; 195 if (fh_len < sizeof(*cfh) / 4) 196 return NULL; 197 198 dout("fh_to_parent %llx\n", cfh->parent_ino); 199 dentry = __get_parent(sb, NULL, cfh->ino); 200 if (IS_ERR(dentry) && PTR_ERR(dentry) == -ENOENT) 201 dentry = __fh_to_dentry(sb, cfh->parent_ino); 202 return dentry; 203 } 204 205 static int ceph_get_name(struct dentry *parent, char *name, 206 struct dentry *child) 207 { 208 struct ceph_mds_client *mdsc; 209 struct ceph_mds_request *req; 210 int err; 211 212 mdsc = ceph_inode_to_client(child->d_inode)->mdsc; 213 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME, 214 USE_ANY_MDS); 215 if (IS_ERR(req)) 216 return PTR_ERR(req); 217 218 mutex_lock(&parent->d_inode->i_mutex); 219 220 req->r_inode = child->d_inode; 221 ihold(child->d_inode); 222 req->r_ino2 = ceph_vino(parent->d_inode); 223 req->r_locked_dir = parent->d_inode; 224 req->r_num_caps = 2; 225 err = ceph_mdsc_do_request(mdsc, NULL, req); 226 227 mutex_unlock(&parent->d_inode->i_mutex); 228 229 if (!err) { 230 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; 231 memcpy(name, rinfo->dname, rinfo->dname_len); 232 name[rinfo->dname_len] = 0; 233 dout("get_name %p ino %llx.%llx name %s\n", 234 child, ceph_vinop(child->d_inode), name); 235 } else { 236 dout("get_name %p ino %llx.%llx err %d\n", 237 child, ceph_vinop(child->d_inode), err); 238 } 239 240 ceph_mdsc_put_request(req); 241 return err; 242 } 243 244 const struct export_operations ceph_export_ops = { 245 .encode_fh = ceph_encode_fh, 246 .fh_to_dentry = ceph_fh_to_dentry, 247 .fh_to_parent = ceph_fh_to_parent, 248 .get_parent = ceph_get_parent, 249 .get_name = ceph_get_name, 250 }; 251