blob: 0ae3a0af192d7085f1484542f6f07d28e0fd1915 [file] [log] [blame]
David Teiglandb3b94fa2006-01-16 16:50:04 +00001/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License v.2.
8 */
9
10#include <linux/sched.h>
11#include <linux/slab.h>
12#include <linux/spinlock.h>
13#include <linux/completion.h>
14#include <linux/buffer_head.h>
15#include <asm/semaphore.h>
16
17#include "gfs2.h"
18#include "dir.h"
19#include "glock.h"
20#include "glops.h"
21#include "inode.h"
22#include "ops_export.h"
23#include "rgrp.h"
24
25static struct dentry *gfs2_decode_fh(struct super_block *sb,
26 __u32 *fh,
27 int fh_len,
28 int fh_type,
29 int (*acceptable)(void *context,
30 struct dentry *dentry),
31 void *context)
32{
33 struct gfs2_inum this, parent;
34
35 atomic_inc(&get_v2sdp(sb)->sd_ops_export);
36
37 if (fh_type != fh_len)
38 return NULL;
39
40 memset(&parent, 0, sizeof(struct gfs2_inum));
41
42 switch (fh_type) {
43 case 8:
44 parent.no_formal_ino = ((uint64_t)be32_to_cpu(fh[4])) << 32;
45 parent.no_formal_ino |= be32_to_cpu(fh[5]);
46 parent.no_addr = ((uint64_t)be32_to_cpu(fh[6])) << 32;
47 parent.no_addr |= be32_to_cpu(fh[7]);
48 case 4:
49 this.no_formal_ino = ((uint64_t)be32_to_cpu(fh[0])) << 32;
50 this.no_formal_ino |= be32_to_cpu(fh[1]);
51 this.no_addr = ((uint64_t)be32_to_cpu(fh[2])) << 32;
52 this.no_addr |= be32_to_cpu(fh[3]);
53 break;
54 default:
55 return NULL;
56 }
57
58 return gfs2_export_ops.find_exported_dentry(sb, &this, &parent,
59 acceptable, context);
60}
61
62static int gfs2_encode_fh(struct dentry *dentry, __u32 *fh, int *len,
63 int connectable)
64{
65 struct inode *inode = dentry->d_inode;
66 struct gfs2_inode *ip = get_v2ip(inode);
67 struct gfs2_sbd *sdp = ip->i_sbd;
68
69 atomic_inc(&sdp->sd_ops_export);
70
71 if (*len < 4 || (connectable && *len < 8))
72 return 255;
73
74 fh[0] = ip->i_num.no_formal_ino >> 32;
75 fh[0] = cpu_to_be32(fh[0]);
76 fh[1] = ip->i_num.no_formal_ino & 0xFFFFFFFF;
77 fh[1] = cpu_to_be32(fh[1]);
78 fh[2] = ip->i_num.no_addr >> 32;
79 fh[2] = cpu_to_be32(fh[2]);
80 fh[3] = ip->i_num.no_addr & 0xFFFFFFFF;
81 fh[3] = cpu_to_be32(fh[3]);
82 *len = 4;
83
84 if (!connectable || ip == sdp->sd_root_dir)
85 return *len;
86
87 spin_lock(&dentry->d_lock);
88 inode = dentry->d_parent->d_inode;
89 ip = get_v2ip(inode);
90 gfs2_inode_hold(ip);
91 spin_unlock(&dentry->d_lock);
92
93 fh[4] = ip->i_num.no_formal_ino >> 32;
94 fh[4] = cpu_to_be32(fh[4]);
95 fh[5] = ip->i_num.no_formal_ino & 0xFFFFFFFF;
96 fh[5] = cpu_to_be32(fh[5]);
97 fh[6] = ip->i_num.no_addr >> 32;
98 fh[6] = cpu_to_be32(fh[6]);
99 fh[7] = ip->i_num.no_addr & 0xFFFFFFFF;
100 fh[7] = cpu_to_be32(fh[7]);
101 *len = 8;
102
103 gfs2_inode_put(ip);
104
105 return *len;
106}
107
108struct get_name_filldir {
109 struct gfs2_inum inum;
110 char *name;
111};
112
113static int get_name_filldir(void *opaque, const char *name, unsigned int length,
114 uint64_t offset, struct gfs2_inum *inum,
115 unsigned int type)
116{
117 struct get_name_filldir *gnfd = (struct get_name_filldir *)opaque;
118
119 if (!gfs2_inum_equal(inum, &gnfd->inum))
120 return 0;
121
122 memcpy(gnfd->name, name, length);
123 gnfd->name[length] = 0;
124
125 return 1;
126}
127
128static int gfs2_get_name(struct dentry *parent, char *name,
129 struct dentry *child)
130{
131 struct inode *dir = parent->d_inode;
132 struct inode *inode = child->d_inode;
133 struct gfs2_inode *dip, *ip;
134 struct get_name_filldir gnfd;
135 struct gfs2_holder gh;
136 uint64_t offset = 0;
137 int error;
138
139 if (!dir)
140 return -EINVAL;
141
142 atomic_inc(&get_v2sdp(dir->i_sb)->sd_ops_export);
143
144 if (!S_ISDIR(dir->i_mode) || !inode)
145 return -EINVAL;
146
147 dip = get_v2ip(dir);
148 ip = get_v2ip(inode);
149
150 *name = 0;
151 gnfd.inum = ip->i_num;
152 gnfd.name = name;
153
154 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
155 if (error)
156 return error;
157
158 error = gfs2_dir_read(dip, &offset, &gnfd, get_name_filldir);
159
160 gfs2_glock_dq_uninit(&gh);
161
162 if (!error && !*name)
163 error = -ENOENT;
164
165 return error;
166}
167
168static struct dentry *gfs2_get_parent(struct dentry *child)
169{
170 struct gfs2_inode *dip = get_v2ip(child->d_inode);
171 struct qstr dotdot = { .name = "..", .len = 2 };
172 struct gfs2_inode *ip;
173 struct inode *inode;
174 struct dentry *dentry;
175 int error;
176
177 atomic_inc(&dip->i_sbd->sd_ops_export);
178
179 error = gfs2_lookupi(dip, &dotdot, 1, &ip);
180 if (error)
181 return ERR_PTR(error);
182
183 inode = gfs2_ip2v(ip);
184 gfs2_inode_put(ip);
185
186 if (!inode)
187 return ERR_PTR(-ENOMEM);
188
189 dentry = d_alloc_anon(inode);
190 if (!dentry) {
191 iput(inode);
192 return ERR_PTR(-ENOMEM);
193 }
194
195 return dentry;
196}
197
198static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_p)
199{
200 struct gfs2_sbd *sdp = get_v2sdp(sb);
201 struct gfs2_inum *inum = (struct gfs2_inum *)inum_p;
202 struct gfs2_holder i_gh, ri_gh, rgd_gh;
203 struct gfs2_rgrpd *rgd;
204 struct gfs2_inode *ip;
205 struct inode *inode;
206 struct dentry *dentry;
207 int error;
208
209 atomic_inc(&sdp->sd_ops_export);
210
211 /* System files? */
212
213 inode = gfs2_iget(sb, inum);
214 if (inode) {
215 ip = get_v2ip(inode);
216 if (ip->i_num.no_formal_ino != inum->no_formal_ino) {
217 iput(inode);
218 return ERR_PTR(-ESTALE);
219 }
220 goto out_inode;
221 }
222
223 error = gfs2_glock_nq_num(sdp,
224 inum->no_addr, &gfs2_inode_glops,
225 LM_ST_SHARED, LM_FLAG_ANY | GL_LOCAL_EXCL,
226 &i_gh);
227 if (error)
228 return ERR_PTR(error);
229
230 error = gfs2_inode_get(i_gh.gh_gl, inum, NO_CREATE, &ip);
231 if (error)
232 goto fail;
233 if (ip)
234 goto out_ip;
235
236 error = gfs2_rindex_hold(sdp, &ri_gh);
237 if (error)
238 goto fail;
239
240 error = -EINVAL;
241 rgd = gfs2_blk2rgrpd(sdp, inum->no_addr);
242 if (!rgd)
243 goto fail_rindex;
244
245 error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
246 if (error)
247 goto fail_rindex;
248
249 error = -ESTALE;
250 if (gfs2_get_block_type(rgd, inum->no_addr) != GFS2_BLKST_DINODE)
251 goto fail_rgd;
252
253 gfs2_glock_dq_uninit(&rgd_gh);
254 gfs2_glock_dq_uninit(&ri_gh);
255
256 error = gfs2_inode_get(i_gh.gh_gl, inum, CREATE, &ip);
257 if (error)
258 goto fail;
259
260 error = gfs2_inode_refresh(ip);
261 if (error) {
262 gfs2_inode_put(ip);
263 goto fail;
264 }
265
266 atomic_inc(&sdp->sd_fh2dentry_misses);
267
268 out_ip:
269 error = -EIO;
270 if (ip->i_di.di_flags & GFS2_DIF_SYSTEM) {
271 gfs2_inode_put(ip);
272 goto fail;
273 }
274
275 gfs2_glock_dq_uninit(&i_gh);
276
277 inode = gfs2_ip2v(ip);
278 gfs2_inode_put(ip);
279
280 if (!inode)
281 return ERR_PTR(-ENOMEM);
282
283 out_inode:
284 dentry = d_alloc_anon(inode);
285 if (!dentry) {
286 iput(inode);
287 return ERR_PTR(-ENOMEM);
288 }
289
290 return dentry;
291
292 fail_rgd:
293 gfs2_glock_dq_uninit(&rgd_gh);
294
295 fail_rindex:
296 gfs2_glock_dq_uninit(&ri_gh);
297
298 fail:
299 gfs2_glock_dq_uninit(&i_gh);
300 return ERR_PTR(error);
301}
302
303struct export_operations gfs2_export_ops = {
304 .decode_fh = gfs2_decode_fh,
305 .encode_fh = gfs2_encode_fh,
306 .get_name = gfs2_get_name,
307 .get_parent = gfs2_get_parent,
308 .get_dentry = gfs2_get_dentry,
309};
310