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 ceph_vino vino; 66 int err; 67 68 vino.ino = ino; 69 vino.snap = CEPH_NOSNAP; 70 inode = ceph_find_inode(sb, vino); 71 if (!inode) { 72 struct ceph_mds_request *req; 73 int mask; 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 mask = CEPH_STAT_CAP_INODE; 81 if (ceph_security_xattr_wanted(d_inode(sb->s_root))) 82 mask |= CEPH_CAP_XATTR_SHARED; 83 req->r_args.getattr.mask = cpu_to_le32(mask); 84 85 req->r_ino1 = vino; 86 req->r_num_caps = 1; 87 err = ceph_mdsc_do_request(mdsc, NULL, req); 88 inode = req->r_target_inode; 89 if (inode) 90 ihold(inode); 91 ceph_mdsc_put_request(req); 92 if (!inode) 93 return ERR_PTR(-ESTALE); 94 if (inode->i_nlink == 0) { 95 iput(inode); 96 return ERR_PTR(-ESTALE); 97 } 98 } 99 100 return d_obtain_alias(inode); 101 } 102 103 /* 104 * convert regular fh to dentry 105 */ 106 static struct dentry *ceph_fh_to_dentry(struct super_block *sb, 107 struct fid *fid, 108 int fh_len, int fh_type) 109 { 110 struct ceph_nfs_fh *fh = (void *)fid->raw; 111 112 if (fh_type != FILEID_INO32_GEN && 113 fh_type != FILEID_INO32_GEN_PARENT) 114 return NULL; 115 if (fh_len < sizeof(*fh) / 4) 116 return NULL; 117 118 dout("fh_to_dentry %llx\n", fh->ino); 119 return __fh_to_dentry(sb, fh->ino); 120 } 121 122 static struct dentry *__get_parent(struct super_block *sb, 123 struct dentry *child, u64 ino) 124 { 125 struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; 126 struct ceph_mds_request *req; 127 struct inode *inode; 128 int mask; 129 int err; 130 131 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT, 132 USE_ANY_MDS); 133 if (IS_ERR(req)) 134 return ERR_CAST(req); 135 136 if (child) { 137 req->r_inode = d_inode(child); 138 ihold(d_inode(child)); 139 } else { 140 req->r_ino1 = (struct ceph_vino) { 141 .ino = ino, 142 .snap = CEPH_NOSNAP, 143 }; 144 } 145 146 mask = CEPH_STAT_CAP_INODE; 147 if (ceph_security_xattr_wanted(d_inode(sb->s_root))) 148 mask |= CEPH_CAP_XATTR_SHARED; 149 req->r_args.getattr.mask = cpu_to_le32(mask); 150 151 req->r_num_caps = 1; 152 err = ceph_mdsc_do_request(mdsc, NULL, req); 153 inode = req->r_target_inode; 154 if (inode) 155 ihold(inode); 156 ceph_mdsc_put_request(req); 157 if (!inode) 158 return ERR_PTR(-ENOENT); 159 160 return d_obtain_alias(inode); 161 } 162 163 static struct dentry *ceph_get_parent(struct dentry *child) 164 { 165 /* don't re-export snaps */ 166 if (ceph_snap(d_inode(child)) != CEPH_NOSNAP) 167 return ERR_PTR(-EINVAL); 168 169 dout("get_parent %p ino %llx.%llx\n", 170 child, ceph_vinop(d_inode(child))); 171 return __get_parent(child->d_sb, child, 0); 172 } 173 174 /* 175 * convert regular fh to parent 176 */ 177 static struct dentry *ceph_fh_to_parent(struct super_block *sb, 178 struct fid *fid, 179 int fh_len, int fh_type) 180 { 181 struct ceph_nfs_confh *cfh = (void *)fid->raw; 182 struct dentry *dentry; 183 184 if (fh_type != FILEID_INO32_GEN_PARENT) 185 return NULL; 186 if (fh_len < sizeof(*cfh) / 4) 187 return NULL; 188 189 dout("fh_to_parent %llx\n", cfh->parent_ino); 190 dentry = __get_parent(sb, NULL, cfh->ino); 191 if (unlikely(dentry == ERR_PTR(-ENOENT))) 192 dentry = __fh_to_dentry(sb, cfh->parent_ino); 193 return dentry; 194 } 195 196 static int ceph_get_name(struct dentry *parent, char *name, 197 struct dentry *child) 198 { 199 struct ceph_mds_client *mdsc; 200 struct ceph_mds_request *req; 201 int err; 202 203 mdsc = ceph_inode_to_client(d_inode(child))->mdsc; 204 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME, 205 USE_ANY_MDS); 206 if (IS_ERR(req)) 207 return PTR_ERR(req); 208 209 inode_lock(d_inode(parent)); 210 211 req->r_inode = d_inode(child); 212 ihold(d_inode(child)); 213 req->r_ino2 = ceph_vino(d_inode(parent)); 214 req->r_parent = d_inode(parent); 215 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); 216 req->r_num_caps = 2; 217 err = ceph_mdsc_do_request(mdsc, NULL, req); 218 219 inode_unlock(d_inode(parent)); 220 221 if (!err) { 222 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; 223 memcpy(name, rinfo->dname, rinfo->dname_len); 224 name[rinfo->dname_len] = 0; 225 dout("get_name %p ino %llx.%llx name %s\n", 226 child, ceph_vinop(d_inode(child)), name); 227 } else { 228 dout("get_name %p ino %llx.%llx err %d\n", 229 child, ceph_vinop(d_inode(child)), err); 230 } 231 232 ceph_mdsc_put_request(req); 233 return err; 234 } 235 236 const struct export_operations ceph_export_ops = { 237 .encode_fh = ceph_encode_fh, 238 .fh_to_dentry = ceph_fh_to_dentry, 239 .fh_to_parent = ceph_fh_to_parent, 240 .get_parent = ceph_get_parent, 241 .get_name = ceph_get_name, 242 }; 243