selftests/powerpc: Add test for VPHN
[linux/fpc-iii.git] / fs / gfs2 / export.c
blobc41d255b6a7b58808d60b205c81ce44f2b0bc75f
1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
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 version 2.
8 */
10 #include <linux/spinlock.h>
11 #include <linux/completion.h>
12 #include <linux/buffer_head.h>
13 #include <linux/exportfs.h>
14 #include <linux/gfs2_ondisk.h>
15 #include <linux/crc32.h>
17 #include "gfs2.h"
18 #include "incore.h"
19 #include "dir.h"
20 #include "glock.h"
21 #include "glops.h"
22 #include "inode.h"
23 #include "super.h"
24 #include "rgrp.h"
25 #include "util.h"
27 #define GFS2_SMALL_FH_SIZE 4
28 #define GFS2_LARGE_FH_SIZE 8
29 #define GFS2_OLD_FH_SIZE 10
31 static int gfs2_encode_fh(struct inode *inode, __u32 *p, int *len,
32 struct inode *parent)
34 __be32 *fh = (__force __be32 *)p;
35 struct super_block *sb = inode->i_sb;
36 struct gfs2_inode *ip = GFS2_I(inode);
38 if (parent && (*len < GFS2_LARGE_FH_SIZE)) {
39 *len = GFS2_LARGE_FH_SIZE;
40 return FILEID_INVALID;
41 } else if (*len < GFS2_SMALL_FH_SIZE) {
42 *len = GFS2_SMALL_FH_SIZE;
43 return FILEID_INVALID;
46 fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
47 fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
48 fh[2] = cpu_to_be32(ip->i_no_addr >> 32);
49 fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
50 *len = GFS2_SMALL_FH_SIZE;
52 if (!parent || inode == sb->s_root->d_inode)
53 return *len;
55 ip = GFS2_I(parent);
57 fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32);
58 fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
59 fh[6] = cpu_to_be32(ip->i_no_addr >> 32);
60 fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
61 *len = GFS2_LARGE_FH_SIZE;
63 return *len;
66 struct get_name_filldir {
67 struct dir_context ctx;
68 struct gfs2_inum_host inum;
69 char *name;
72 static int get_name_filldir(struct dir_context *ctx, const char *name,
73 int length, loff_t offset, u64 inum,
74 unsigned int type)
76 struct get_name_filldir *gnfd =
77 container_of(ctx, struct get_name_filldir, ctx);
79 if (inum != gnfd->inum.no_addr)
80 return 0;
82 memcpy(gnfd->name, name, length);
83 gnfd->name[length] = 0;
85 return 1;
88 static int gfs2_get_name(struct dentry *parent, char *name,
89 struct dentry *child)
91 struct inode *dir = parent->d_inode;
92 struct inode *inode = child->d_inode;
93 struct gfs2_inode *dip, *ip;
94 struct get_name_filldir gnfd = {
95 .ctx.actor = get_name_filldir,
96 .name = name
98 struct gfs2_holder gh;
99 int error;
100 struct file_ra_state f_ra = { .start = 0 };
102 if (!dir)
103 return -EINVAL;
105 if (!S_ISDIR(dir->i_mode) || !inode)
106 return -EINVAL;
108 dip = GFS2_I(dir);
109 ip = GFS2_I(inode);
111 *name = 0;
112 gnfd.inum.no_addr = ip->i_no_addr;
113 gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
115 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
116 if (error)
117 return error;
119 error = gfs2_dir_read(dir, &gnfd.ctx, &f_ra);
121 gfs2_glock_dq_uninit(&gh);
123 if (!error && !*name)
124 error = -ENOENT;
126 return error;
129 static struct dentry *gfs2_get_parent(struct dentry *child)
131 return d_obtain_alias(gfs2_lookupi(child->d_inode, &gfs2_qdotdot, 1));
134 static struct dentry *gfs2_get_dentry(struct super_block *sb,
135 struct gfs2_inum_host *inum)
137 struct gfs2_sbd *sdp = sb->s_fs_info;
138 struct inode *inode;
140 inode = gfs2_ilookup(sb, inum->no_addr, 0);
141 if (inode) {
142 if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
143 iput(inode);
144 return ERR_PTR(-ESTALE);
146 goto out_inode;
149 inode = gfs2_lookup_by_inum(sdp, inum->no_addr, &inum->no_formal_ino,
150 GFS2_BLKST_DINODE);
151 if (IS_ERR(inode))
152 return ERR_CAST(inode);
154 out_inode:
155 return d_obtain_alias(inode);
158 static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
159 int fh_len, int fh_type)
161 struct gfs2_inum_host this;
162 __be32 *fh = (__force __be32 *)fid->raw;
164 switch (fh_type) {
165 case GFS2_SMALL_FH_SIZE:
166 case GFS2_LARGE_FH_SIZE:
167 case GFS2_OLD_FH_SIZE:
168 if (fh_len < GFS2_SMALL_FH_SIZE)
169 return NULL;
170 this.no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32;
171 this.no_formal_ino |= be32_to_cpu(fh[1]);
172 this.no_addr = ((u64)be32_to_cpu(fh[2])) << 32;
173 this.no_addr |= be32_to_cpu(fh[3]);
174 return gfs2_get_dentry(sb, &this);
175 default:
176 return NULL;
180 static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
181 int fh_len, int fh_type)
183 struct gfs2_inum_host parent;
184 __be32 *fh = (__force __be32 *)fid->raw;
186 switch (fh_type) {
187 case GFS2_LARGE_FH_SIZE:
188 case GFS2_OLD_FH_SIZE:
189 if (fh_len < GFS2_LARGE_FH_SIZE)
190 return NULL;
191 parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
192 parent.no_formal_ino |= be32_to_cpu(fh[5]);
193 parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
194 parent.no_addr |= be32_to_cpu(fh[7]);
195 return gfs2_get_dentry(sb, &parent);
196 default:
197 return NULL;
201 const struct export_operations gfs2_export_ops = {
202 .encode_fh = gfs2_encode_fh,
203 .fh_to_dentry = gfs2_fh_to_dentry,
204 .fh_to_parent = gfs2_fh_to_parent,
205 .get_name = gfs2_get_name,
206 .get_parent = gfs2_get_parent,