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v4.6
  1/*
  2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
  3 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
  4 *
  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 */
  9
 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>
 16
 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"
 26
 27#define GFS2_SMALL_FH_SIZE 4
 28#define GFS2_LARGE_FH_SIZE 8
 29#define GFS2_OLD_FH_SIZE 10
 30
 31static int gfs2_encode_fh(struct inode *inode, __u32 *p, int *len,
 32			  struct inode *parent)
 33{
 34	__be32 *fh = (__force __be32 *)p;
 
 35	struct super_block *sb = inode->i_sb;
 36	struct gfs2_inode *ip = GFS2_I(inode);
 37
 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;
 44	}
 45
 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;
 51
 52	if (!parent || inode == d_inode(sb->s_root))
 53		return *len;
 54
 55	ip = GFS2_I(parent);
 
 
 
 
 56
 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;
 62
 
 
 63	return *len;
 64}
 65
 66struct get_name_filldir {
 67	struct dir_context ctx;
 68	struct gfs2_inum_host inum;
 69	char *name;
 70};
 71
 72static int get_name_filldir(struct dir_context *ctx, const char *name,
 73			    int length, loff_t offset, u64 inum,
 74			    unsigned int type)
 75{
 76	struct get_name_filldir *gnfd =
 77		container_of(ctx, struct get_name_filldir, ctx);
 78
 79	if (inum != gnfd->inum.no_addr)
 80		return 0;
 81
 82	memcpy(gnfd->name, name, length);
 83	gnfd->name[length] = 0;
 84
 85	return 1;
 86}
 87
 88static int gfs2_get_name(struct dentry *parent, char *name,
 89			 struct dentry *child)
 90{
 91	struct inode *dir = d_inode(parent);
 92	struct inode *inode = d_inode(child);
 93	struct gfs2_inode *dip, *ip;
 94	struct get_name_filldir gnfd = {
 95		.ctx.actor = get_name_filldir,
 96		.name = name
 97	};
 98	struct gfs2_holder gh;
 
 99	int error;
100	struct file_ra_state f_ra = { .start = 0 };
101
102	if (!dir)
103		return -EINVAL;
104
105	if (!S_ISDIR(dir->i_mode) || !inode)
106		return -EINVAL;
107
108	dip = GFS2_I(dir);
109	ip = GFS2_I(inode);
110
111	*name = 0;
112	gnfd.inum.no_addr = ip->i_no_addr;
113	gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
 
114
115	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
116	if (error)
117		return error;
118
119	error = gfs2_dir_read(dir, &gnfd.ctx, &f_ra);
120
121	gfs2_glock_dq_uninit(&gh);
122
123	if (!error && !*name)
124		error = -ENOENT;
125
126	return error;
127}
128
129static struct dentry *gfs2_get_parent(struct dentry *child)
130{
131	return d_obtain_alias(gfs2_lookupi(d_inode(child), &gfs2_qdotdot, 1));
132}
133
134static struct dentry *gfs2_get_dentry(struct super_block *sb,
135				      struct gfs2_inum_host *inum)
136{
137	struct gfs2_sbd *sdp = sb->s_fs_info;
138	struct inode *inode;
139
140	inode = gfs2_ilookup(sb, inum->no_addr);
141	if (inode) {
142		if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
143			iput(inode);
144			return ERR_PTR(-ESTALE);
145		}
146		goto out_inode;
147	}
148
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);
153
154out_inode:
155	return d_obtain_alias(inode);
156}
157
158static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
159		int fh_len, int fh_type)
160{
161	struct gfs2_inum_host this;
162	__be32 *fh = (__force __be32 *)fid->raw;
163
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;
177	}
178}
179
180static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
181		int fh_len, int fh_type)
182{
183	struct gfs2_inum_host parent;
184	__be32 *fh = (__force __be32 *)fid->raw;
185
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;
198	}
199}
200
201const 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,
207};
208
v3.1
  1/*
  2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
  3 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
  4 *
  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 */
  9
 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>
 16
 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"
 26
 27#define GFS2_SMALL_FH_SIZE 4
 28#define GFS2_LARGE_FH_SIZE 8
 29#define GFS2_OLD_FH_SIZE 10
 30
 31static int gfs2_encode_fh(struct dentry *dentry, __u32 *p, int *len,
 32			  int connectable)
 33{
 34	__be32 *fh = (__force __be32 *)p;
 35	struct inode *inode = dentry->d_inode;
 36	struct super_block *sb = inode->i_sb;
 37	struct gfs2_inode *ip = GFS2_I(inode);
 38
 39	if (connectable && (*len < GFS2_LARGE_FH_SIZE)) {
 40		*len = GFS2_LARGE_FH_SIZE;
 41		return 255;
 42	} else if (*len < GFS2_SMALL_FH_SIZE) {
 43		*len = GFS2_SMALL_FH_SIZE;
 44		return 255;
 45	}
 46
 47	fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
 48	fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
 49	fh[2] = cpu_to_be32(ip->i_no_addr >> 32);
 50	fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
 51	*len = GFS2_SMALL_FH_SIZE;
 52
 53	if (!connectable || inode == sb->s_root->d_inode)
 54		return *len;
 55
 56	spin_lock(&dentry->d_lock);
 57	inode = dentry->d_parent->d_inode;
 58	ip = GFS2_I(inode);
 59	igrab(inode);
 60	spin_unlock(&dentry->d_lock);
 61
 62	fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32);
 63	fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
 64	fh[6] = cpu_to_be32(ip->i_no_addr >> 32);
 65	fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
 66	*len = GFS2_LARGE_FH_SIZE;
 67
 68	iput(inode);
 69
 70	return *len;
 71}
 72
 73struct get_name_filldir {
 
 74	struct gfs2_inum_host inum;
 75	char *name;
 76};
 77
 78static int get_name_filldir(void *opaque, const char *name, int length,
 79			    loff_t offset, u64 inum, unsigned int type)
 
 80{
 81	struct get_name_filldir *gnfd = opaque;
 
 82
 83	if (inum != gnfd->inum.no_addr)
 84		return 0;
 85
 86	memcpy(gnfd->name, name, length);
 87	gnfd->name[length] = 0;
 88
 89	return 1;
 90}
 91
 92static int gfs2_get_name(struct dentry *parent, char *name,
 93			 struct dentry *child)
 94{
 95	struct inode *dir = parent->d_inode;
 96	struct inode *inode = child->d_inode;
 97	struct gfs2_inode *dip, *ip;
 98	struct get_name_filldir gnfd;
 
 
 
 99	struct gfs2_holder gh;
100	u64 offset = 0;
101	int error;
 
102
103	if (!dir)
104		return -EINVAL;
105
106	if (!S_ISDIR(dir->i_mode) || !inode)
107		return -EINVAL;
108
109	dip = GFS2_I(dir);
110	ip = GFS2_I(inode);
111
112	*name = 0;
113	gnfd.inum.no_addr = ip->i_no_addr;
114	gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
115	gnfd.name = name;
116
117	error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
118	if (error)
119		return error;
120
121	error = gfs2_dir_read(dir, &offset, &gnfd, get_name_filldir);
122
123	gfs2_glock_dq_uninit(&gh);
124
125	if (!error && !*name)
126		error = -ENOENT;
127
128	return error;
129}
130
131static struct dentry *gfs2_get_parent(struct dentry *child)
132{
133	return d_obtain_alias(gfs2_lookupi(child->d_inode, &gfs2_qdotdot, 1));
134}
135
136static struct dentry *gfs2_get_dentry(struct super_block *sb,
137				      struct gfs2_inum_host *inum)
138{
139	struct gfs2_sbd *sdp = sb->s_fs_info;
140	struct inode *inode;
141
142	inode = gfs2_ilookup(sb, inum->no_addr, 0);
143	if (inode) {
144		if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
145			iput(inode);
146			return ERR_PTR(-ESTALE);
147		}
148		goto out_inode;
149	}
150
151	inode = gfs2_lookup_by_inum(sdp, inum->no_addr, &inum->no_formal_ino,
152				    GFS2_BLKST_DINODE);
153	if (IS_ERR(inode))
154		return ERR_CAST(inode);
155
156out_inode:
157	return d_obtain_alias(inode);
158}
159
160static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
161		int fh_len, int fh_type)
162{
163	struct gfs2_inum_host this;
164	__be32 *fh = (__force __be32 *)fid->raw;
165
166	switch (fh_type) {
167	case GFS2_SMALL_FH_SIZE:
168	case GFS2_LARGE_FH_SIZE:
169	case GFS2_OLD_FH_SIZE:
 
 
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;
177	}
178}
179
180static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
181		int fh_len, int fh_type)
182{
183	struct gfs2_inum_host parent;
184	__be32 *fh = (__force __be32 *)fid->raw;
185
186	switch (fh_type) {
187	case GFS2_LARGE_FH_SIZE:
188	case GFS2_OLD_FH_SIZE:
 
 
189		parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
190		parent.no_formal_ino |= be32_to_cpu(fh[5]);
191		parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
192		parent.no_addr |= be32_to_cpu(fh[7]);
193		return gfs2_get_dentry(sb, &parent);
194	default:
195		return NULL;
196	}
197}
198
199const struct export_operations gfs2_export_ops = {
200	.encode_fh = gfs2_encode_fh,
201	.fh_to_dentry = gfs2_fh_to_dentry,
202	.fh_to_parent = gfs2_fh_to_parent,
203	.get_name = gfs2_get_name,
204	.get_parent = gfs2_get_parent,
205};
206