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
ceph_encode_fh(struct inode * inode,u32 * rawfh,int * max_len,struct inode * parent_inode)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
__fh_to_dentry(struct super_block * sb,u64 ino)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 */
ceph_fh_to_dentry(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)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
__get_parent(struct super_block * sb,struct dentry * child,u64 ino)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 = d_inode(child);
140 ihold(d_inode(child));
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 if (err) {
150 ceph_mdsc_put_request(req);
151 return ERR_PTR(err);
152 }
153
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 dentry = d_obtain_alias(inode);
162 if (IS_ERR(dentry)) {
163 iput(inode);
164 return dentry;
165 }
166 err = ceph_init_dentry(dentry);
167 if (err < 0) {
168 dput(dentry);
169 return ERR_PTR(err);
170 }
171 dout("__get_parent ino %llx parent %p ino %llx.%llx\n",
172 child ? ceph_ino(d_inode(child)) : ino,
173 dentry, ceph_vinop(inode));
174 return dentry;
175 }
176
ceph_get_parent(struct dentry * child)177 static struct dentry *ceph_get_parent(struct dentry *child)
178 {
179 /* don't re-export snaps */
180 if (ceph_snap(d_inode(child)) != CEPH_NOSNAP)
181 return ERR_PTR(-EINVAL);
182
183 dout("get_parent %p ino %llx.%llx\n",
184 child, ceph_vinop(d_inode(child)));
185 return __get_parent(child->d_sb, child, 0);
186 }
187
188 /*
189 * convert regular fh to parent
190 */
ceph_fh_to_parent(struct super_block * sb,struct fid * fid,int fh_len,int fh_type)191 static struct dentry *ceph_fh_to_parent(struct super_block *sb,
192 struct fid *fid,
193 int fh_len, int fh_type)
194 {
195 struct ceph_nfs_confh *cfh = (void *)fid->raw;
196 struct dentry *dentry;
197
198 if (fh_type != FILEID_INO32_GEN_PARENT)
199 return NULL;
200 if (fh_len < sizeof(*cfh) / 4)
201 return NULL;
202
203 dout("fh_to_parent %llx\n", cfh->parent_ino);
204 dentry = __get_parent(sb, NULL, cfh->ino);
205 if (IS_ERR(dentry) && PTR_ERR(dentry) == -ENOENT)
206 dentry = __fh_to_dentry(sb, cfh->parent_ino);
207 return dentry;
208 }
209
ceph_get_name(struct dentry * parent,char * name,struct dentry * child)210 static int ceph_get_name(struct dentry *parent, char *name,
211 struct dentry *child)
212 {
213 struct ceph_mds_client *mdsc;
214 struct ceph_mds_request *req;
215 int err;
216
217 mdsc = ceph_inode_to_client(d_inode(child))->mdsc;
218 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME,
219 USE_ANY_MDS);
220 if (IS_ERR(req))
221 return PTR_ERR(req);
222
223 mutex_lock(&d_inode(parent)->i_mutex);
224
225 req->r_inode = d_inode(child);
226 ihold(d_inode(child));
227 req->r_ino2 = ceph_vino(d_inode(parent));
228 req->r_locked_dir = d_inode(parent);
229 req->r_num_caps = 2;
230 err = ceph_mdsc_do_request(mdsc, NULL, req);
231
232 mutex_unlock(&d_inode(parent)->i_mutex);
233
234 if (!err) {
235 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
236 memcpy(name, rinfo->dname, rinfo->dname_len);
237 name[rinfo->dname_len] = 0;
238 dout("get_name %p ino %llx.%llx name %s\n",
239 child, ceph_vinop(d_inode(child)), name);
240 } else {
241 dout("get_name %p ino %llx.%llx err %d\n",
242 child, ceph_vinop(d_inode(child)), err);
243 }
244
245 ceph_mdsc_put_request(req);
246 return err;
247 }
248
249 const struct export_operations ceph_export_ops = {
250 .encode_fh = ceph_encode_fh,
251 .fh_to_dentry = ceph_fh_to_dentry,
252 .fh_to_parent = ceph_fh_to_parent,
253 .get_parent = ceph_get_parent,
254 .get_name = ceph_get_name,
255 };
256