| 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 | 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 | } |
| 96 | |
| 97 | dentry = d_obtain_alias(inode); |
| 98 | if (IS_ERR(dentry)) |
| 99 | return dentry; |
| 100 | err = ceph_init_dentry(dentry); |
| 101 | if (err < 0) { |
| 102 | dput(dentry); |
| 103 | return ERR_PTR(err); |
| 104 | } |
| 105 | dout("__fh_to_dentry %llx %p dentry %p\n", ino, inode, dentry); |
| 106 | return dentry; |
| 107 | } |
| 108 | |
| 109 | /* |
| 110 | * convert regular fh to dentry |
| 111 | */ |
| 112 | static struct dentry *ceph_fh_to_dentry(struct super_block *sb, |
| 113 | struct fid *fid, |
| 114 | int fh_len, int fh_type) |
| 115 | { |
| 116 | struct ceph_nfs_fh *fh = (void *)fid->raw; |
| 117 | |
| 118 | if (fh_type != FILEID_INO32_GEN && |
| 119 | fh_type != FILEID_INO32_GEN_PARENT) |
| 120 | return NULL; |
| 121 | if (fh_len < sizeof(*fh) / 4) |
| 122 | return NULL; |
| 123 | |
| 124 | dout("fh_to_dentry %llx\n", fh->ino); |
| 125 | return __fh_to_dentry(sb, fh->ino); |
| 126 | } |
| 127 | |
| 128 | static struct dentry *__get_parent(struct super_block *sb, |
| 129 | struct dentry *child, u64 ino) |
| 130 | { |
| 131 | struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; |
| 132 | struct ceph_mds_request *req; |
| 133 | struct inode *inode; |
| 134 | struct dentry *dentry; |
| 135 | int mask; |
| 136 | int err; |
| 137 | |
| 138 | req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT, |
| 139 | USE_ANY_MDS); |
| 140 | if (IS_ERR(req)) |
| 141 | return ERR_CAST(req); |
| 142 | |
| 143 | if (child) { |
| 144 | req->r_inode = d_inode(child); |
| 145 | ihold(d_inode(child)); |
| 146 | } else { |
| 147 | req->r_ino1 = (struct ceph_vino) { |
| 148 | .ino = ino, |
| 149 | .snap = CEPH_NOSNAP, |
| 150 | }; |
| 151 | } |
| 152 | |
| 153 | mask = CEPH_STAT_CAP_INODE; |
| 154 | if (ceph_security_xattr_wanted(d_inode(sb->s_root))) |
| 155 | mask |= CEPH_CAP_XATTR_SHARED; |
| 156 | req->r_args.getattr.mask = cpu_to_le32(mask); |
| 157 | |
| 158 | req->r_num_caps = 1; |
| 159 | err = ceph_mdsc_do_request(mdsc, NULL, req); |
| 160 | inode = req->r_target_inode; |
| 161 | if (inode) |
| 162 | ihold(inode); |
| 163 | ceph_mdsc_put_request(req); |
| 164 | if (!inode) |
| 165 | return ERR_PTR(-ENOENT); |
| 166 | |
| 167 | dentry = d_obtain_alias(inode); |
| 168 | if (IS_ERR(dentry)) |
| 169 | return dentry; |
| 170 | err = ceph_init_dentry(dentry); |
| 171 | if (err < 0) { |
| 172 | dput(dentry); |
| 173 | return ERR_PTR(err); |
| 174 | } |
| 175 | dout("__get_parent ino %llx parent %p ino %llx.%llx\n", |
| 176 | child ? ceph_ino(d_inode(child)) : ino, |
| 177 | dentry, ceph_vinop(inode)); |
| 178 | return dentry; |
| 179 | } |
| 180 | |
| 181 | static struct dentry *ceph_get_parent(struct dentry *child) |
| 182 | { |
| 183 | /* don't re-export snaps */ |
| 184 | if (ceph_snap(d_inode(child)) != CEPH_NOSNAP) |
| 185 | return ERR_PTR(-EINVAL); |
| 186 | |
| 187 | dout("get_parent %p ino %llx.%llx\n", |
| 188 | child, ceph_vinop(d_inode(child))); |
| 189 | return __get_parent(child->d_sb, child, 0); |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * convert regular fh to parent |
| 194 | */ |
| 195 | static struct dentry *ceph_fh_to_parent(struct super_block *sb, |
| 196 | struct fid *fid, |
| 197 | int fh_len, int fh_type) |
| 198 | { |
| 199 | struct ceph_nfs_confh *cfh = (void *)fid->raw; |
| 200 | struct dentry *dentry; |
| 201 | |
| 202 | if (fh_type != FILEID_INO32_GEN_PARENT) |
| 203 | return NULL; |
| 204 | if (fh_len < sizeof(*cfh) / 4) |
| 205 | return NULL; |
| 206 | |
| 207 | dout("fh_to_parent %llx\n", cfh->parent_ino); |
| 208 | dentry = __get_parent(sb, NULL, cfh->ino); |
| 209 | if (unlikely(dentry == ERR_PTR(-ENOENT))) |
| 210 | dentry = __fh_to_dentry(sb, cfh->parent_ino); |
| 211 | return dentry; |
| 212 | } |
| 213 | |
| 214 | static int ceph_get_name(struct dentry *parent, char *name, |
| 215 | struct dentry *child) |
| 216 | { |
| 217 | struct ceph_mds_client *mdsc; |
| 218 | struct ceph_mds_request *req; |
| 219 | int err; |
| 220 | |
| 221 | mdsc = ceph_inode_to_client(d_inode(child))->mdsc; |
| 222 | req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME, |
| 223 | USE_ANY_MDS); |
| 224 | if (IS_ERR(req)) |
| 225 | return PTR_ERR(req); |
| 226 | |
| 227 | inode_lock(d_inode(parent)); |
| 228 | |
| 229 | req->r_inode = d_inode(child); |
| 230 | ihold(d_inode(child)); |
| 231 | req->r_ino2 = ceph_vino(d_inode(parent)); |
| 232 | req->r_locked_dir = d_inode(parent); |
| 233 | req->r_num_caps = 2; |
| 234 | err = ceph_mdsc_do_request(mdsc, NULL, req); |
| 235 | |
| 236 | inode_unlock(d_inode(parent)); |
| 237 | |
| 238 | if (!err) { |
| 239 | struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; |
| 240 | memcpy(name, rinfo->dname, rinfo->dname_len); |
| 241 | name[rinfo->dname_len] = 0; |
| 242 | dout("get_name %p ino %llx.%llx name %s\n", |
| 243 | child, ceph_vinop(d_inode(child)), name); |
| 244 | } else { |
| 245 | dout("get_name %p ino %llx.%llx err %d\n", |
| 246 | child, ceph_vinop(d_inode(child)), err); |
| 247 | } |
| 248 | |
| 249 | ceph_mdsc_put_request(req); |
| 250 | return err; |
| 251 | } |
| 252 | |
| 253 | const struct export_operations ceph_export_ops = { |
| 254 | .encode_fh = ceph_encode_fh, |
| 255 | .fh_to_dentry = ceph_fh_to_dentry, |
| 256 | .fh_to_parent = ceph_fh_to_parent, |
| 257 | .get_parent = ceph_get_parent, |
| 258 | .get_name = ceph_get_name, |
| 259 | }; |