blob: 51a8a14deb29df71c605f64b78f02c05d9fe89c7 [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
David Teiglandb3b94fa2006-01-16 16:50:04 +000010#include <linux/slab.h>
11#include <linux/spinlock.h>
12#include <linux/completion.h>
13#include <linux/buffer_head.h>
Steven Whitehouse5c676f62006-02-27 17:23:27 -050014#include <linux/gfs2_ondisk.h>
Steven Whitehouse71b86f52006-03-28 14:14:04 -050015#include <linux/crc32.h>
Fabio Massimo Di Nitto7d308592006-09-19 07:56:29 +020016#include <linux/lm_interface.h>
David Teiglandb3b94fa2006-01-16 16:50:04 +000017
18#include "gfs2.h"
Steven Whitehouse5c676f62006-02-27 17:23:27 -050019#include "incore.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000020#include "dir.h"
21#include "glock.h"
22#include "glops.h"
23#include "inode.h"
Robert Peterson70831462007-01-11 13:25:00 -060024#include "ops_dentry.h"
David Teiglandb3b94fa2006-01-16 16:50:04 +000025#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,
Al Virob44b84d2006-10-14 10:46:30 -040030 __u32 *p,
David Teiglandb3b94fa2006-01-16 16:50:04 +000031 int fh_len,
32 int fh_type,
33 int (*acceptable)(void *context,
34 struct dentry *dentry),
35 void *context)
36{
Al Virob44b84d2006-10-14 10:46:30 -040037 __be32 *fh = (__force __be32 *)p;
Wendy Cheng2eb168c2006-07-11 13:28:53 -040038 struct gfs2_fh_obj fh_obj;
Al Viro629a21e2006-10-13 22:51:24 -040039 struct gfs2_inum_host *this, parent;
David Teiglandb3b94fa2006-01-16 16:50:04 +000040
Wendy Cheng2eb168c2006-07-11 13:28:53 -040041 this = &fh_obj.this;
42 fh_obj.imode = DT_UNKNOWN;
David Teiglandb3b94fa2006-01-16 16:50:04 +000043 memset(&parent, 0, sizeof(struct gfs2_inum));
44
Wendy Chenga7d2b2b2007-02-23 00:21:17 -050045 switch (fh_len) {
Steven Whitehouse5acd3962006-09-04 16:16:45 -040046 case GFS2_LARGE_FH_SIZE:
Steven Whitehousecd915492006-09-04 12:49:07 -040047 parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
David Teiglandb3b94fa2006-01-16 16:50:04 +000048 parent.no_formal_ino |= be32_to_cpu(fh[5]);
Steven Whitehousecd915492006-09-04 12:49:07 -040049 parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
David Teiglandb3b94fa2006-01-16 16:50:04 +000050 parent.no_addr |= be32_to_cpu(fh[7]);
Wendy Cheng2eb168c2006-07-11 13:28:53 -040051 fh_obj.imode = be32_to_cpu(fh[8]);
Steven Whitehouse5acd3962006-09-04 16:16:45 -040052 case GFS2_SMALL_FH_SIZE:
Steven Whitehousecd915492006-09-04 12:49:07 -040053 this->no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32;
Wendy Cheng2eb168c2006-07-11 13:28:53 -040054 this->no_formal_ino |= be32_to_cpu(fh[1]);
Steven Whitehousecd915492006-09-04 12:49:07 -040055 this->no_addr = ((u64)be32_to_cpu(fh[2])) << 32;
Wendy Cheng2eb168c2006-07-11 13:28:53 -040056 this->no_addr |= be32_to_cpu(fh[3]);
David Teiglandb3b94fa2006-01-16 16:50:04 +000057 break;
58 default:
59 return NULL;
60 }
61
Wendy Cheng2eb168c2006-07-11 13:28:53 -040062 return gfs2_export_ops.find_exported_dentry(sb, &fh_obj, &parent,
David Teiglandb3b94fa2006-01-16 16:50:04 +000063 acceptable, context);
64}
65
Al Virob44b84d2006-10-14 10:46:30 -040066static int gfs2_encode_fh(struct dentry *dentry, __u32 *p, int *len,
David Teiglandb3b94fa2006-01-16 16:50:04 +000067 int connectable)
68{
Al Virob44b84d2006-10-14 10:46:30 -040069 __be32 *fh = (__force __be32 *)p;
David Teiglandb3b94fa2006-01-16 16:50:04 +000070 struct inode *inode = dentry->d_inode;
Steven Whitehousec9fd4302006-03-01 15:31:02 -050071 struct super_block *sb = inode->i_sb;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -040072 struct gfs2_inode *ip = GFS2_I(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +000073
Steven Whitehouse5acd3962006-09-04 16:16:45 -040074 if (*len < GFS2_SMALL_FH_SIZE ||
75 (connectable && *len < GFS2_LARGE_FH_SIZE))
David Teiglandb3b94fa2006-01-16 16:50:04 +000076 return 255;
77
Steven Whitehousedbb7cae2007-05-15 15:37:50 +010078 fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
79 fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
80 fh[2] = cpu_to_be32(ip->i_no_addr >> 32);
81 fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
Steven Whitehouse5acd3962006-09-04 16:16:45 -040082 *len = GFS2_SMALL_FH_SIZE;
David Teiglandb3b94fa2006-01-16 16:50:04 +000083
Steven Whitehousec9fd4302006-03-01 15:31:02 -050084 if (!connectable || inode == sb->s_root->d_inode)
David Teiglandb3b94fa2006-01-16 16:50:04 +000085 return *len;
86
87 spin_lock(&dentry->d_lock);
88 inode = dentry->d_parent->d_inode;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -040089 ip = GFS2_I(inode);
90 igrab(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +000091 spin_unlock(&dentry->d_lock);
92
Steven Whitehousedbb7cae2007-05-15 15:37:50 +010093 fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32);
94 fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
95 fh[6] = cpu_to_be32(ip->i_no_addr >> 32);
96 fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
Wendy Cheng2eb168c2006-07-11 13:28:53 -040097
98 fh[8] = cpu_to_be32(inode->i_mode);
99 fh[9] = 0; /* pad to double word */
Steven Whitehouse5acd3962006-09-04 16:16:45 -0400100 *len = GFS2_LARGE_FH_SIZE;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000101
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400102 iput(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000103
104 return *len;
105}
106
107struct get_name_filldir {
Al Viro629a21e2006-10-13 22:51:24 -0400108 struct gfs2_inum_host inum;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000109 char *name;
110};
111
Steven Whitehouse3699e3a2007-01-17 15:09:20 +0000112static int get_name_filldir(void *opaque, const char *name, int length,
113 loff_t offset, u64 inum, unsigned int type)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000114{
Steven Whitehouse3699e3a2007-01-17 15:09:20 +0000115 struct get_name_filldir *gnfd = opaque;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000116
Steven Whitehouse3699e3a2007-01-17 15:09:20 +0000117 if (inum != gnfd->inum.no_addr)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000118 return 0;
119
120 memcpy(gnfd->name, name, length);
121 gnfd->name[length] = 0;
122
123 return 1;
124}
125
126static int gfs2_get_name(struct dentry *parent, char *name,
127 struct dentry *child)
128{
129 struct inode *dir = parent->d_inode;
130 struct inode *inode = child->d_inode;
131 struct gfs2_inode *dip, *ip;
132 struct get_name_filldir gnfd;
133 struct gfs2_holder gh;
Steven Whitehousecd915492006-09-04 12:49:07 -0400134 u64 offset = 0;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000135 int error;
136
137 if (!dir)
138 return -EINVAL;
139
David Teiglandb3b94fa2006-01-16 16:50:04 +0000140 if (!S_ISDIR(dir->i_mode) || !inode)
141 return -EINVAL;
142
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400143 dip = GFS2_I(dir);
144 ip = GFS2_I(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000145
146 *name = 0;
Steven Whitehousedbb7cae2007-05-15 15:37:50 +0100147 gnfd.inum.no_addr = ip->i_no_addr;
148 gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000149 gnfd.name = name;
150
151 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
152 if (error)
153 return error;
154
Steven Whitehouse71b86f52006-03-28 14:14:04 -0500155 error = gfs2_dir_read(dir, &offset, &gnfd, get_name_filldir);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000156
157 gfs2_glock_dq_uninit(&gh);
158
159 if (!error && !*name)
160 error = -ENOENT;
161
162 return error;
163}
164
165static struct dentry *gfs2_get_parent(struct dentry *child)
166{
Steven Whitehouse71b86f52006-03-28 14:14:04 -0500167 struct qstr dotdot;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000168 struct inode *inode;
169 struct dentry *dentry;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000170
Steven Whitehouse71b86f52006-03-28 14:14:04 -0500171 gfs2_str2qstr(&dotdot, "..");
Steven Whitehousec7526662006-03-20 12:30:04 -0500172 inode = gfs2_lookupi(child->d_inode, &dotdot, 1, NULL);
173
174 if (!inode)
175 return ERR_PTR(-ENOENT);
Steven Whitehouse7b625362006-09-05 15:56:17 -0400176 /*
177 * In case of an error, @inode carries the error value, and we
178 * have to return that as a(n invalid) pointer to dentry.
179 */
Steven Whitehousec7526662006-03-20 12:30:04 -0500180 if (IS_ERR(inode))
181 return ERR_PTR(PTR_ERR(inode));
David Teiglandb3b94fa2006-01-16 16:50:04 +0000182
David Teiglandb3b94fa2006-01-16 16:50:04 +0000183 dentry = d_alloc_anon(inode);
184 if (!dentry) {
185 iput(inode);
186 return ERR_PTR(-ENOMEM);
187 }
188
Robert Peterson70831462007-01-11 13:25:00 -0600189 dentry->d_op = &gfs2_dops;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000190 return dentry;
191}
192
Wendy Cheng2eb168c2006-07-11 13:28:53 -0400193static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_obj)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000194{
Steven Whitehouse5c676f62006-02-27 17:23:27 -0500195 struct gfs2_sbd *sdp = sb->s_fs_info;
Wendy Cheng2eb168c2006-07-11 13:28:53 -0400196 struct gfs2_fh_obj *fh_obj = (struct gfs2_fh_obj *)inum_obj;
Al Viro629a21e2006-10-13 22:51:24 -0400197 struct gfs2_inum_host *inum = &fh_obj->this;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000198 struct gfs2_holder i_gh, ri_gh, rgd_gh;
199 struct gfs2_rgrpd *rgd;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000200 struct inode *inode;
201 struct dentry *dentry;
202 int error;
203
David Teiglandb3b94fa2006-01-16 16:50:04 +0000204 /* System files? */
205
Steven Whitehousedbb7cae2007-05-15 15:37:50 +0100206 inode = gfs2_ilookup(sb, inum->no_addr);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000207 if (inode) {
Steven Whitehousedbb7cae2007-05-15 15:37:50 +0100208 if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
David Teiglandb3b94fa2006-01-16 16:50:04 +0000209 iput(inode);
210 return ERR_PTR(-ESTALE);
211 }
212 goto out_inode;
213 }
214
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400215 error = gfs2_glock_nq_num(sdp, inum->no_addr, &gfs2_inode_glops,
Steven Whitehouse1c0f4872007-01-22 12:10:39 -0500216 LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000217 if (error)
218 return ERR_PTR(error);
219
David Teiglandb3b94fa2006-01-16 16:50:04 +0000220 error = gfs2_rindex_hold(sdp, &ri_gh);
221 if (error)
222 goto fail;
223
224 error = -EINVAL;
225 rgd = gfs2_blk2rgrpd(sdp, inum->no_addr);
226 if (!rgd)
227 goto fail_rindex;
228
229 error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
230 if (error)
231 goto fail_rindex;
232
233 error = -ESTALE;
234 if (gfs2_get_block_type(rgd, inum->no_addr) != GFS2_BLKST_DINODE)
235 goto fail_rgd;
236
237 gfs2_glock_dq_uninit(&rgd_gh);
238 gfs2_glock_dq_uninit(&ri_gh);
239
Steven Whitehousedbb7cae2007-05-15 15:37:50 +0100240 inode = gfs2_inode_lookup(sb, inum->no_addr, fh_obj->imode);
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400241 if (!inode)
David Teiglandb3b94fa2006-01-16 16:50:04 +0000242 goto fail;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400243 if (IS_ERR(inode)) {
244 error = PTR_ERR(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000245 goto fail;
246 }
247
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400248 error = gfs2_inode_refresh(GFS2_I(inode));
249 if (error) {
250 iput(inode);
251 goto fail;
252 }
Steven Whitehousedbb7cae2007-05-15 15:37:50 +0100253 if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
254 iput(inode);
255 goto fail;
256 }
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400257
David Teiglandb3b94fa2006-01-16 16:50:04 +0000258 error = -EIO;
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400259 if (GFS2_I(inode)->i_di.di_flags & GFS2_DIF_SYSTEM) {
260 iput(inode);
David Teiglandb3b94fa2006-01-16 16:50:04 +0000261 goto fail;
262 }
263
264 gfs2_glock_dq_uninit(&i_gh);
265
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400266out_inode:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000267 dentry = d_alloc_anon(inode);
268 if (!dentry) {
269 iput(inode);
270 return ERR_PTR(-ENOMEM);
271 }
272
Robert Peterson70831462007-01-11 13:25:00 -0600273 dentry->d_op = &gfs2_dops;
David Teiglandb3b94fa2006-01-16 16:50:04 +0000274 return dentry;
275
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400276fail_rgd:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000277 gfs2_glock_dq_uninit(&rgd_gh);
278
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400279fail_rindex:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000280 gfs2_glock_dq_uninit(&ri_gh);
281
Steven Whitehousefeaa7bb2006-06-14 15:32:57 -0400282fail:
David Teiglandb3b94fa2006-01-16 16:50:04 +0000283 gfs2_glock_dq_uninit(&i_gh);
284 return ERR_PTR(error);
285}
286
287struct export_operations gfs2_export_ops = {
288 .decode_fh = gfs2_decode_fh,
289 .encode_fh = gfs2_encode_fh,
290 .get_name = gfs2_get_name,
291 .get_parent = gfs2_get_parent,
292 .get_dentry = gfs2_get_dentry,
293};
294