blob: 86127d93bd35f6f846f7d5b46f53cfd4fa0ccb53 [file] [log] [blame]
David Teiglandb3b94fa2006-01-16 16:50:04 +00001/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
Steven Whitehouse3a8a9a12006-05-18 15:09:15 -04003 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
David Teiglandb3b94fa2006-01-16 16:50:04 +00004 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
Steven Whitehousee9fc2aa2006-09-01 11:05:15 -04007 * of the GNU General Public License version 2.
David Teiglandb3b94fa2006-01-16 16:50:04 +00008 */
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>
Steven Whitehouse5c676f62006-02-27 17:23:27 -050015#include <linux/gfs2_ondisk.h>
Steven Whitehouse71b86f52006-03-28 14:14:04 -050016#include <linux/crc32.h>
Fabio Massimo Di Nitto7d308592006-09-19 07:56:29 +020017#include <linux/lm_interface.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000018
19#include "gfs2.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050020#include "incore.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000021#include "dir.h"
22#include "glock.h"
23#include "glops.h"
24#include "inode.h"
25#include "ops_export.h"
26#include "rgrp.h"
Steven Whitehousec7526662006-03-20 12:30:04 -050027#include "util.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000028
29static struct dentry *gfs2_decode_fh(struct super_block *sb,
30 __u32 *fh,
31 int fh_len,
32 int fh_type,
33 int (*acceptable)(void *context,
34 struct dentry *dentry),
35 void *context)
36{
Wendy Cheng2eb168c2006-07-11 13:28:53 -040037 struct gfs2_fh_obj fh_obj;
38 struct gfs2_inum *this, parent;
David Teiglandb3b94fa2006-01-16 16:50:04 +000039
David Teiglandb3b94fa2006-01-16 16:50:04 +000040 if (fh_type != fh_len)
41 return NULL;
42
Wendy Cheng2eb168c2006-07-11 13:28:53 -040043 this = &fh_obj.this;
44 fh_obj.imode = DT_UNKNOWN;
David Teiglandb3b94fa2006-01-16 16:50:04 +000045 memset(&parent, 0, sizeof(struct gfs2_inum));
46
47 switch (fh_type) {
Steven Whitehouse5acd3962006-09-04 16:16:45 -040048 case GFS2_LARGE_FH_SIZE:
Steven Whitehousecd915492006-09-04 12:49:07 -040049 parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
David Teiglandb3b94fa2006-01-16 16:50:04 +000050 parent.no_formal_ino |= be32_to_cpu(fh[5]);
Steven Whitehousecd915492006-09-04 12:49:07 -040051 parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
David Teiglandb3b94fa2006-01-16 16:50:04 +000052 parent.no_addr |= be32_to_cpu(fh[7]);
Wendy Cheng2eb168c2006-07-11 13:28:53 -040053 fh_obj.imode = be32_to_cpu(fh[8]);
Steven Whitehouse5acd3962006-09-04 16:16:45 -040054 case GFS2_SMALL_FH_SIZE:
Steven Whitehousecd915492006-09-04 12:49:07 -040055 this->no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32;
Wendy Cheng2eb168c2006-07-11 13:28:53 -040056 this->no_formal_ino |= be32_to_cpu(fh[1]);
Steven Whitehousecd915492006-09-04 12:49:07 -040057 this->no_addr = ((u64)be32_to_cpu(fh[2])) << 32;
Wendy Cheng2eb168c2006-07-11 13:28:53 -040058 this->no_addr |= be32_to_cpu(fh[3]);
David Teiglandb3b94fa2006-01-16 16:50:04 +000059 break;
60 default:
61 return NULL;
62 }
63
Wendy Cheng2eb168c2006-07-11 13:28:53 -040064 return gfs2_export_ops.find_exported_dentry(sb, &fh_obj, &parent,
David Teiglandb3b94fa2006-01-16 16:50:04 +000065 acceptable, context);
66}
67
68static int gfs2_encode_fh(struct dentry *dentry, __u32 *fh, int *len,
69 int connectable)
70{
71 struct inode *inode = dentry->d_inode;
Steven Whitehousec9fd4302006-03-01 15:31:02 -050072 struct super_block *sb = inode->i_sb;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -040073 struct gfs2_inode *ip = GFS2_I(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +000074
Steven Whitehouse5acd3962006-09-04 16:16:45 -040075 if (*len < GFS2_SMALL_FH_SIZE ||
76 (connectable && *len < GFS2_LARGE_FH_SIZE))
David Teiglandb3b94fa2006-01-16 16:50:04 +000077 return 255;
78
79 fh[0] = ip->i_num.no_formal_ino >> 32;
80 fh[0] = cpu_to_be32(fh[0]);
81 fh[1] = ip->i_num.no_formal_ino & 0xFFFFFFFF;
82 fh[1] = cpu_to_be32(fh[1]);
83 fh[2] = ip->i_num.no_addr >> 32;
84 fh[2] = cpu_to_be32(fh[2]);
85 fh[3] = ip->i_num.no_addr & 0xFFFFFFFF;
86 fh[3] = cpu_to_be32(fh[3]);
Steven Whitehouse5acd3962006-09-04 16:16:45 -040087 *len = GFS2_SMALL_FH_SIZE;
David Teiglandb3b94fa2006-01-16 16:50:04 +000088
Steven Whitehousec9fd4302006-03-01 15:31:02 -050089 if (!connectable || inode == sb->s_root->d_inode)
David Teiglandb3b94fa2006-01-16 16:50:04 +000090 return *len;
91
92 spin_lock(&dentry->d_lock);
93 inode = dentry->d_parent->d_inode;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -040094 ip = GFS2_I(inode);
95 igrab(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +000096 spin_unlock(&dentry->d_lock);
97
98 fh[4] = ip->i_num.no_formal_ino >> 32;
99 fh[4] = cpu_to_be32(fh[4]);
100 fh[5] = ip->i_num.no_formal_ino & 0xFFFFFFFF;
101 fh[5] = cpu_to_be32(fh[5]);
102 fh[6] = ip->i_num.no_addr >> 32;
103 fh[6] = cpu_to_be32(fh[6]);
104 fh[7] = ip->i_num.no_addr & 0xFFFFFFFF;
105 fh[7] = cpu_to_be32(fh[7]);
Wendy Cheng2eb168c2006-07-11 13:28:53 -0400106
107 fh[8] = cpu_to_be32(inode->i_mode);
108 fh[9] = 0; /* pad to double word */
Steven Whitehouse5acd3962006-09-04 16:16:45 -0400109 *len = GFS2_LARGE_FH_SIZE;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000110
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400111 iput(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000112
113 return *len;
114}
115
116struct get_name_filldir {
117 struct gfs2_inum inum;
118 char *name;
119};
120
121static int get_name_filldir(void *opaque, const char *name, unsigned int length,
Steven Whitehousecd915492006-09-04 12:49:07 -0400122 u64 offset, struct gfs2_inum *inum,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000123 unsigned int type)
124{
125 struct get_name_filldir *gnfd = (struct get_name_filldir *)opaque;
126
127 if (!gfs2_inum_equal(inum, &gnfd->inum))
128 return 0;
129
130 memcpy(gnfd->name, name, length);
131 gnfd->name[length] = 0;
132
133 return 1;
134}
135
136static int gfs2_get_name(struct dentry *parent, char *name,
137 struct dentry *child)
138{
139 struct inode *dir = parent->d_inode;
140 struct inode *inode = child->d_inode;
141 struct gfs2_inode *dip, *ip;
142 struct get_name_filldir gnfd;
143 struct gfs2_holder gh;
Steven Whitehousecd915492006-09-04 12:49:07 -0400144 u64 offset = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000145 int error;
146
147 if (!dir)
148 return -EINVAL;
149
David Teiglandb3b94fa2006-01-16 16:50:04 +0000150 if (!S_ISDIR(dir->i_mode) || !inode)
151 return -EINVAL;
152
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400153 dip = GFS2_I(dir);
154 ip = GFS2_I(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000155
156 *name = 0;
157 gnfd.inum = ip->i_num;
158 gnfd.name = name;
159
160 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
161 if (error)
162 return error;
163
Steven Whitehouse71b86f52006-03-28 14:14:04 -0500164 error = gfs2_dir_read(dir, &offset, &gnfd, get_name_filldir);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000165
166 gfs2_glock_dq_uninit(&gh);
167
168 if (!error && !*name)
169 error = -ENOENT;
170
171 return error;
172}
173
174static struct dentry *gfs2_get_parent(struct dentry *child)
175{
Steven Whitehouse71b86f52006-03-28 14:14:04 -0500176 struct qstr dotdot;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000177 struct inode *inode;
178 struct dentry *dentry;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000179
Steven Whitehouse71b86f52006-03-28 14:14:04 -0500180 gfs2_str2qstr(&dotdot, "..");
Steven Whitehousec7526662006-03-20 12:30:04 -0500181 inode = gfs2_lookupi(child->d_inode, &dotdot, 1, NULL);
182
183 if (!inode)
184 return ERR_PTR(-ENOENT);
Steven Whitehouse7b625362006-09-05 15:56:17 -0400185 /*
186 * In case of an error, @inode carries the error value, and we
187 * have to return that as a(n invalid) pointer to dentry.
188 */
Steven Whitehousec7526662006-03-20 12:30:04 -0500189 if (IS_ERR(inode))
190 return ERR_PTR(PTR_ERR(inode));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000191
David Teiglandb3b94fa2006-01-16 16:50:04 +0000192 dentry = d_alloc_anon(inode);
193 if (!dentry) {
194 iput(inode);
195 return ERR_PTR(-ENOMEM);
196 }
197
198 return dentry;
199}
200
Wendy Cheng2eb168c2006-07-11 13:28:53 -0400201static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_obj)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000202{
Steven Whitehouse5c676f62006-02-27 17:23:27 -0500203 struct gfs2_sbd *sdp = sb->s_fs_info;
Wendy Cheng2eb168c2006-07-11 13:28:53 -0400204 struct gfs2_fh_obj *fh_obj = (struct gfs2_fh_obj *)inum_obj;
205 struct gfs2_inum *inum = &fh_obj->this;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000206 struct gfs2_holder i_gh, ri_gh, rgd_gh;
207 struct gfs2_rgrpd *rgd;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000208 struct inode *inode;
209 struct dentry *dentry;
210 int error;
211
David Teiglandb3b94fa2006-01-16 16:50:04 +0000212 /* System files? */
213
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400214 inode = gfs2_ilookup(sb, inum);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000215 if (inode) {
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400216 if (GFS2_I(inode)->i_num.no_formal_ino != inum->no_formal_ino) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000217 iput(inode);
218 return ERR_PTR(-ESTALE);
219 }
220 goto out_inode;
221 }
222
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400223 error = gfs2_glock_nq_num(sdp, inum->no_addr, &gfs2_inode_glops,
David Teiglandb3b94fa2006-01-16 16:50:04 +0000224 LM_ST_SHARED, LM_FLAG_ANY | GL_LOCAL_EXCL,
225 &i_gh);
226 if (error)
227 return ERR_PTR(error);
228
David Teiglandb3b94fa2006-01-16 16:50:04 +0000229 error = gfs2_rindex_hold(sdp, &ri_gh);
230 if (error)
231 goto fail;
232
233 error = -EINVAL;
234 rgd = gfs2_blk2rgrpd(sdp, inum->no_addr);
235 if (!rgd)
236 goto fail_rindex;
237
238 error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
239 if (error)
240 goto fail_rindex;
241
242 error = -ESTALE;
243 if (gfs2_get_block_type(rgd, inum->no_addr) != GFS2_BLKST_DINODE)
244 goto fail_rgd;
245
246 gfs2_glock_dq_uninit(&rgd_gh);
247 gfs2_glock_dq_uninit(&ri_gh);
248
Wendy Cheng2eb168c2006-07-11 13:28:53 -0400249 inode = gfs2_inode_lookup(sb, inum, fh_obj->imode);
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400250 if (!inode)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000251 goto fail;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400252 if (IS_ERR(inode)) {
253 error = PTR_ERR(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000254 goto fail;
255 }
256
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400257 error = gfs2_inode_refresh(GFS2_I(inode));
258 if (error) {
259 iput(inode);
260 goto fail;
261 }
262
David Teiglandb3b94fa2006-01-16 16:50:04 +0000263 error = -EIO;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400264 if (GFS2_I(inode)->i_di.di_flags & GFS2_DIF_SYSTEM) {
265 iput(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000266 goto fail;
267 }
268
269 gfs2_glock_dq_uninit(&i_gh);
270
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400271out_inode:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000272 dentry = d_alloc_anon(inode);
273 if (!dentry) {
274 iput(inode);
275 return ERR_PTR(-ENOMEM);
276 }
277
278 return dentry;
279
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400280fail_rgd:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000281 gfs2_glock_dq_uninit(&rgd_gh);
282
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400283fail_rindex:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000284 gfs2_glock_dq_uninit(&ri_gh);
285
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400286fail:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000287 gfs2_glock_dq_uninit(&i_gh);
288 return ERR_PTR(error);
289}
290
291struct export_operations gfs2_export_ops = {
292 .decode_fh = gfs2_decode_fh,
293 .encode_fh = gfs2_encode_fh,
294 .get_name = gfs2_get_name,
295 .get_parent = gfs2_get_parent,
296 .get_dentry = gfs2_get_dentry,
297};
298