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.
10 #include <linux/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/exportfs.h>
15 #include <linux/gfs2_ondisk.h>
16 #include <linux/crc32.h>
28 #define GFS2_SMALL_FH_SIZE 4
29 #define GFS2_LARGE_FH_SIZE 8
30 #define GFS2_OLD_FH_SIZE 10
32 static int gfs2_encode_fh(struct dentry *dentry, __u32 *p, int *len,
35 __be32 *fh = (__force __be32 *)p;
36 struct inode *inode = dentry->d_inode;
37 struct super_block *sb = inode->i_sb;
38 struct gfs2_inode *ip = GFS2_I(inode);
40 if (*len < GFS2_SMALL_FH_SIZE ||
41 (connectable && *len < GFS2_LARGE_FH_SIZE))
44 fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
45 fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
46 fh[2] = cpu_to_be32(ip->i_no_addr >> 32);
47 fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
48 *len = GFS2_SMALL_FH_SIZE;
50 if (!connectable || inode == sb->s_root->d_inode)
53 spin_lock(&dentry->d_lock);
54 inode = dentry->d_parent->d_inode;
57 spin_unlock(&dentry->d_lock);
59 fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32);
60 fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
61 fh[6] = cpu_to_be32(ip->i_no_addr >> 32);
62 fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
63 *len = GFS2_LARGE_FH_SIZE;
70 struct get_name_filldir {
71 struct gfs2_inum_host inum;
75 static int get_name_filldir(void *opaque, const char *name, int length,
76 loff_t offset, u64 inum, unsigned int type)
78 struct get_name_filldir *gnfd = opaque;
80 if (inum != gnfd->inum.no_addr)
83 memcpy(gnfd->name, name, length);
84 gnfd->name[length] = 0;
89 static int gfs2_get_name(struct dentry *parent, char *name,
92 struct inode *dir = parent->d_inode;
93 struct inode *inode = child->d_inode;
94 struct gfs2_inode *dip, *ip;
95 struct get_name_filldir gnfd;
96 struct gfs2_holder gh;
103 if (!S_ISDIR(dir->i_mode) || !inode)
110 gnfd.inum.no_addr = ip->i_no_addr;
111 gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
114 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
118 error = gfs2_dir_read(dir, &offset, &gnfd, get_name_filldir);
120 gfs2_glock_dq_uninit(&gh);
122 if (!error && !*name)
128 static struct dentry *gfs2_get_parent(struct dentry *child)
131 struct dentry *dentry;
134 * XXX(hch): it would be a good idea to keep this around as a
137 gfs2_str2qstr(&dotdot, "..");
139 dentry = d_obtain_alias(gfs2_lookupi(child->d_inode, &dotdot, 1));
141 dentry->d_op = &gfs2_dops;
145 static struct dentry *gfs2_get_dentry(struct super_block *sb,
146 struct gfs2_inum_host *inum)
148 struct gfs2_sbd *sdp = sb->s_fs_info;
149 struct gfs2_holder i_gh;
151 struct dentry *dentry;
154 inode = gfs2_ilookup(sb, inum->no_addr);
156 if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
158 return ERR_PTR(-ESTALE);
163 error = gfs2_glock_nq_num(sdp, inum->no_addr, &gfs2_inode_glops,
164 LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
166 return ERR_PTR(error);
168 error = gfs2_check_blk_type(sdp, inum->no_addr, GFS2_BLKST_DINODE);
172 inode = gfs2_inode_lookup(sb, DT_UNKNOWN, inum->no_addr, 0, 0);
174 error = PTR_ERR(inode);
178 error = gfs2_inode_refresh(GFS2_I(inode));
184 /* Pick up the works we bypass in gfs2_inode_lookup */
185 if (inode->i_state & I_NEW)
188 if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
194 if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM) {
199 gfs2_glock_dq_uninit(&i_gh);
202 dentry = d_obtain_alias(inode);
204 dentry->d_op = &gfs2_dops;
207 gfs2_glock_dq_uninit(&i_gh);
208 return ERR_PTR(error);
211 static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
212 int fh_len, int fh_type)
214 struct gfs2_inum_host this;
215 __be32 *fh = (__force __be32 *)fid->raw;
218 case GFS2_SMALL_FH_SIZE:
219 case GFS2_LARGE_FH_SIZE:
220 case GFS2_OLD_FH_SIZE:
221 this.no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32;
222 this.no_formal_ino |= be32_to_cpu(fh[1]);
223 this.no_addr = ((u64)be32_to_cpu(fh[2])) << 32;
224 this.no_addr |= be32_to_cpu(fh[3]);
225 return gfs2_get_dentry(sb, &this);
231 static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
232 int fh_len, int fh_type)
234 struct gfs2_inum_host parent;
235 __be32 *fh = (__force __be32 *)fid->raw;
238 case GFS2_LARGE_FH_SIZE:
239 case GFS2_OLD_FH_SIZE:
240 parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
241 parent.no_formal_ino |= be32_to_cpu(fh[5]);
242 parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
243 parent.no_addr |= be32_to_cpu(fh[7]);
244 return gfs2_get_dentry(sb, &parent);
250 const struct export_operations gfs2_export_ops = {
251 .encode_fh = gfs2_encode_fh,
252 .fh_to_dentry = gfs2_fh_to_dentry,
253 .fh_to_parent = gfs2_fh_to_parent,
254 .get_name = gfs2_get_name,
255 .get_parent = gfs2_get_parent,