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>
17 #include <linux/lm_interface.h>
29 #define GFS2_SMALL_FH_SIZE 4
30 #define GFS2_LARGE_FH_SIZE 8
31 #define GFS2_OLD_FH_SIZE 10
33 static int gfs2_encode_fh(struct dentry *dentry, __u32 *p, int *len,
36 __be32 *fh = (__force __be32 *)p;
37 struct inode *inode = dentry->d_inode;
38 struct super_block *sb = inode->i_sb;
39 struct gfs2_inode *ip = GFS2_I(inode);
41 if (*len < GFS2_SMALL_FH_SIZE ||
42 (connectable && *len < GFS2_LARGE_FH_SIZE))
45 fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
46 fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
47 fh[2] = cpu_to_be32(ip->i_no_addr >> 32);
48 fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
49 *len = GFS2_SMALL_FH_SIZE;
51 if (!connectable || inode == sb->s_root->d_inode)
54 spin_lock(&dentry->d_lock);
55 inode = dentry->d_parent->d_inode;
58 spin_unlock(&dentry->d_lock);
60 fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32);
61 fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
62 fh[6] = cpu_to_be32(ip->i_no_addr >> 32);
63 fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
64 *len = GFS2_LARGE_FH_SIZE;
71 struct get_name_filldir {
72 struct gfs2_inum_host inum;
76 static int get_name_filldir(void *opaque, const char *name, int length,
77 loff_t offset, u64 inum, unsigned int type)
79 struct get_name_filldir *gnfd = opaque;
81 if (inum != gnfd->inum.no_addr)
84 memcpy(gnfd->name, name, length);
85 gnfd->name[length] = 0;
90 static int gfs2_get_name(struct dentry *parent, char *name,
93 struct inode *dir = parent->d_inode;
94 struct inode *inode = child->d_inode;
95 struct gfs2_inode *dip, *ip;
96 struct get_name_filldir gnfd;
97 struct gfs2_holder gh;
104 if (!S_ISDIR(dir->i_mode) || !inode)
111 gnfd.inum.no_addr = ip->i_no_addr;
112 gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
115 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
119 error = gfs2_dir_read(dir, &offset, &gnfd, get_name_filldir);
121 gfs2_glock_dq_uninit(&gh);
123 if (!error && !*name)
129 static struct dentry *gfs2_get_parent(struct dentry *child)
132 struct dentry *dentry;
135 * XXX(hch): it would be a good idea to keep this around as a
138 gfs2_str2qstr(&dotdot, "..");
140 dentry = d_obtain_alias(gfs2_lookupi(child->d_inode, &dotdot, 1));
142 dentry->d_op = &gfs2_dops;
146 static struct dentry *gfs2_get_dentry(struct super_block *sb,
147 struct gfs2_inum_host *inum)
149 struct gfs2_sbd *sdp = sb->s_fs_info;
150 struct gfs2_holder i_gh, ri_gh, rgd_gh;
151 struct gfs2_rgrpd *rgd;
153 struct dentry *dentry;
158 inode = gfs2_ilookup(sb, inum->no_addr);
160 if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
162 return ERR_PTR(-ESTALE);
167 error = gfs2_glock_nq_num(sdp, inum->no_addr, &gfs2_inode_glops,
168 LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
170 return ERR_PTR(error);
172 error = gfs2_rindex_hold(sdp, &ri_gh);
177 rgd = gfs2_blk2rgrpd(sdp, inum->no_addr);
181 error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
186 if (gfs2_get_block_type(rgd, inum->no_addr) != GFS2_BLKST_DINODE)
189 gfs2_glock_dq_uninit(&rgd_gh);
190 gfs2_glock_dq_uninit(&ri_gh);
192 inode = gfs2_inode_lookup(sb, DT_UNKNOWN,
196 error = PTR_ERR(inode);
200 error = gfs2_inode_refresh(GFS2_I(inode));
206 /* Pick up the works we bypass in gfs2_inode_lookup */
207 if (inode->i_state & I_NEW)
210 if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
216 if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM) {
221 gfs2_glock_dq_uninit(&i_gh);
224 dentry = d_obtain_alias(inode);
226 dentry->d_op = &gfs2_dops;
230 gfs2_glock_dq_uninit(&rgd_gh);
233 gfs2_glock_dq_uninit(&ri_gh);
236 gfs2_glock_dq_uninit(&i_gh);
237 return ERR_PTR(error);
240 static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
241 int fh_len, int fh_type)
243 struct gfs2_inum_host this;
244 __be32 *fh = (__force __be32 *)fid->raw;
247 case GFS2_SMALL_FH_SIZE:
248 case GFS2_LARGE_FH_SIZE:
249 case GFS2_OLD_FH_SIZE:
250 this.no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32;
251 this.no_formal_ino |= be32_to_cpu(fh[1]);
252 this.no_addr = ((u64)be32_to_cpu(fh[2])) << 32;
253 this.no_addr |= be32_to_cpu(fh[3]);
254 return gfs2_get_dentry(sb, &this);
260 static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
261 int fh_len, int fh_type)
263 struct gfs2_inum_host parent;
264 __be32 *fh = (__force __be32 *)fid->raw;
267 case GFS2_LARGE_FH_SIZE:
268 case GFS2_OLD_FH_SIZE:
269 parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
270 parent.no_formal_ino |= be32_to_cpu(fh[5]);
271 parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
272 parent.no_addr |= be32_to_cpu(fh[7]);
273 return gfs2_get_dentry(sb, &parent);
279 const struct export_operations gfs2_export_ops = {
280 .encode_fh = gfs2_encode_fh,
281 .fh_to_dentry = gfs2_fh_to_dentry,
282 .fh_to_parent = gfs2_fh_to_parent,
283 .get_name = gfs2_get_name,
284 .get_parent = gfs2_get_parent,