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DEFINITIONS
This source file includes following definitions.
- gfs2_encode_fh
- get_name_filldir
- gfs2_get_name
- gfs2_get_parent
- gfs2_get_dentry
- gfs2_fh_to_dentry
- gfs2_fh_to_parent
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/exportfs.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/lm_interface.h>
#include "gfs2.h"
#include "incore.h"
#include "dir.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "ops_dentry.h"
#include "ops_fstype.h"
#include "rgrp.h"
#include "util.h"
#define GFS2_SMALL_FH_SIZE 4
#define GFS2_LARGE_FH_SIZE 8
#define GFS2_OLD_FH_SIZE 10
static int gfs2_encode_fh(struct dentry *dentry, __u32 *p, int *len,
int connectable)
{
__be32 *fh = (__force __be32 *)p;
struct inode *inode = dentry->d_inode;
struct super_block *sb = inode->i_sb;
struct gfs2_inode *ip = GFS2_I(inode);
if (*len < GFS2_SMALL_FH_SIZE ||
(connectable && *len < GFS2_LARGE_FH_SIZE))
return 255;
fh[0] = cpu_to_be32(ip->i_no_formal_ino >> 32);
fh[1] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
fh[2] = cpu_to_be32(ip->i_no_addr >> 32);
fh[3] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
*len = GFS2_SMALL_FH_SIZE;
if (!connectable || inode == sb->s_root->d_inode)
return *len;
spin_lock(&dentry->d_lock);
inode = dentry->d_parent->d_inode;
ip = GFS2_I(inode);
igrab(inode);
spin_unlock(&dentry->d_lock);
fh[4] = cpu_to_be32(ip->i_no_formal_ino >> 32);
fh[5] = cpu_to_be32(ip->i_no_formal_ino & 0xFFFFFFFF);
fh[6] = cpu_to_be32(ip->i_no_addr >> 32);
fh[7] = cpu_to_be32(ip->i_no_addr & 0xFFFFFFFF);
*len = GFS2_LARGE_FH_SIZE;
iput(inode);
return *len;
}
struct get_name_filldir {
struct gfs2_inum_host inum;
char *name;
};
static int get_name_filldir(void *opaque, const char *name, int length,
loff_t offset, u64 inum, unsigned int type)
{
struct get_name_filldir *gnfd = opaque;
if (inum != gnfd->inum.no_addr)
return 0;
memcpy(gnfd->name, name, length);
gnfd->name[length] = 0;
return 1;
}
static int gfs2_get_name(struct dentry *parent, char *name,
struct dentry *child)
{
struct inode *dir = parent->d_inode;
struct inode *inode = child->d_inode;
struct gfs2_inode *dip, *ip;
struct get_name_filldir gnfd;
struct gfs2_holder gh;
u64 offset = 0;
int error;
if (!dir)
return -EINVAL;
if (!S_ISDIR(dir->i_mode) || !inode)
return -EINVAL;
dip = GFS2_I(dir);
ip = GFS2_I(inode);
*name = 0;
gnfd.inum.no_addr = ip->i_no_addr;
gnfd.inum.no_formal_ino = ip->i_no_formal_ino;
gnfd.name = name;
error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &gh);
if (error)
return error;
error = gfs2_dir_read(dir, &offset, &gnfd, get_name_filldir);
gfs2_glock_dq_uninit(&gh);
if (!error && !*name)
error = -ENOENT;
return error;
}
static struct dentry *gfs2_get_parent(struct dentry *child)
{
struct qstr dotdot;
struct inode *inode;
struct dentry *dentry;
gfs2_str2qstr(&dotdot, "..");
inode = gfs2_lookupi(child->d_inode, &dotdot, 1);
if (!inode)
return ERR_PTR(-ENOENT);
/*
* In case of an error, @inode carries the error value, and we
* have to return that as a(n invalid) pointer to dentry.
*/
if (IS_ERR(inode))
return ERR_CAST(inode);
dentry = d_alloc_anon(inode);
if (!dentry) {
iput(inode);
return ERR_PTR(-ENOMEM);
}
dentry->d_op = &gfs2_dops;
return dentry;
}
static struct dentry *gfs2_get_dentry(struct super_block *sb,
struct gfs2_inum_host *inum)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
struct gfs2_holder i_gh, ri_gh, rgd_gh;
struct gfs2_rgrpd *rgd;
struct inode *inode;
struct dentry *dentry;
int error;
/* System files? */
inode = gfs2_ilookup(sb, inum->no_addr);
if (inode) {
if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
iput(inode);
return ERR_PTR(-ESTALE);
}
goto out_inode;
}
error = gfs2_glock_nq_num(sdp, inum->no_addr, &gfs2_inode_glops,
LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
if (error)
return ERR_PTR(error);
error = gfs2_rindex_hold(sdp, &ri_gh);
if (error)
goto fail;
error = -EINVAL;
rgd = gfs2_blk2rgrpd(sdp, inum->no_addr);
if (!rgd)
goto fail_rindex;
error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_SHARED, 0, &rgd_gh);
if (error)
goto fail_rindex;
error = -ESTALE;
if (gfs2_get_block_type(rgd, inum->no_addr) != GFS2_BLKST_DINODE)
goto fail_rgd;
gfs2_glock_dq_uninit(&rgd_gh);
gfs2_glock_dq_uninit(&ri_gh);
inode = gfs2_inode_lookup(sb, DT_UNKNOWN,
inum->no_addr,
0, 0);
if (IS_ERR(inode)) {
error = PTR_ERR(inode);
goto fail;
}
error = gfs2_inode_refresh(GFS2_I(inode));
if (error) {
iput(inode);
goto fail;
}
/* Pick up the works we bypass in gfs2_inode_lookup */
if (inode->i_state & I_NEW)
gfs2_set_iop(inode);
if (GFS2_I(inode)->i_no_formal_ino != inum->no_formal_ino) {
iput(inode);
goto fail;
}
error = -EIO;
if (GFS2_I(inode)->i_di.di_flags & GFS2_DIF_SYSTEM) {
iput(inode);
goto fail;
}
gfs2_glock_dq_uninit(&i_gh);
out_inode:
dentry = d_alloc_anon(inode);
if (!dentry) {
iput(inode);
return ERR_PTR(-ENOMEM);
}
dentry->d_op = &gfs2_dops;
return dentry;
fail_rgd:
gfs2_glock_dq_uninit(&rgd_gh);
fail_rindex:
gfs2_glock_dq_uninit(&ri_gh);
fail:
gfs2_glock_dq_uninit(&i_gh);
return ERR_PTR(error);
}
static struct dentry *gfs2_fh_to_dentry(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct gfs2_inum_host this;
__be32 *fh = (__force __be32 *)fid->raw;
switch (fh_type) {
case GFS2_SMALL_FH_SIZE:
case GFS2_LARGE_FH_SIZE:
case GFS2_OLD_FH_SIZE:
this.no_formal_ino = ((u64)be32_to_cpu(fh[0])) << 32;
this.no_formal_ino |= be32_to_cpu(fh[1]);
this.no_addr = ((u64)be32_to_cpu(fh[2])) << 32;
this.no_addr |= be32_to_cpu(fh[3]);
return gfs2_get_dentry(sb, &this);
default:
return NULL;
}
}
static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct gfs2_inum_host parent;
__be32 *fh = (__force __be32 *)fid->raw;
switch (fh_type) {
case GFS2_LARGE_FH_SIZE:
case GFS2_OLD_FH_SIZE:
parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
parent.no_formal_ino |= be32_to_cpu(fh[5]);
parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
parent.no_addr |= be32_to_cpu(fh[7]);
return gfs2_get_dentry(sb, &parent);
default:
return NULL;
}
}
const struct export_operations gfs2_export_ops = {
.encode_fh = gfs2_encode_fh,
.fh_to_dentry = gfs2_fh_to_dentry,
.fh_to_parent = gfs2_fh_to_parent,
.get_name = gfs2_get_name,
.get_parent = gfs2_get_parent,
};