kernel-fxtec-pro1x/fs/gfs2/ops_export.c
Steven Whitehouse 71b86f562b [GFS2] Further updates to dir and logging code
This reduces the size of the directory code by about 3k and gets
readdir() to use the functions which were introduced in the previous
directory code update.

Two memory allocations are merged into one. Eliminates zeroing of some
buffers which were never used before they were initialised by
other data.

There is still scope for further improvement in the directory code.

On the logging side, a hand created mutex has been replaced by a
standard Linux mutex in the log allocation code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-03-28 14:14:04 -05:00

298 lines
6.3 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2005 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 v.2.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <asm/semaphore.h>
#include "gfs2.h"
#include "lm_interface.h"
#include "incore.h"
#include "dir.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "ops_export.h"
#include "rgrp.h"
#include "util.h"
static struct dentry *gfs2_decode_fh(struct super_block *sb,
__u32 *fh,
int fh_len,
int fh_type,
int (*acceptable)(void *context,
struct dentry *dentry),
void *context)
{
struct gfs2_inum this, parent;
if (fh_type != fh_len)
return NULL;
memset(&parent, 0, sizeof(struct gfs2_inum));
switch (fh_type) {
case 8:
parent.no_formal_ino = ((uint64_t)be32_to_cpu(fh[4])) << 32;
parent.no_formal_ino |= be32_to_cpu(fh[5]);
parent.no_addr = ((uint64_t)be32_to_cpu(fh[6])) << 32;
parent.no_addr |= be32_to_cpu(fh[7]);
case 4:
this.no_formal_ino = ((uint64_t)be32_to_cpu(fh[0])) << 32;
this.no_formal_ino |= be32_to_cpu(fh[1]);
this.no_addr = ((uint64_t)be32_to_cpu(fh[2])) << 32;
this.no_addr |= be32_to_cpu(fh[3]);
break;
default:
return NULL;
}
return gfs2_export_ops.find_exported_dentry(sb, &this, &parent,
acceptable, context);
}
static int gfs2_encode_fh(struct dentry *dentry, __u32 *fh, int *len,
int connectable)
{
struct inode *inode = dentry->d_inode;
struct super_block *sb = inode->i_sb;
struct gfs2_inode *ip = inode->u.generic_ip;
if (*len < 4 || (connectable && *len < 8))
return 255;
fh[0] = ip->i_num.no_formal_ino >> 32;
fh[0] = cpu_to_be32(fh[0]);
fh[1] = ip->i_num.no_formal_ino & 0xFFFFFFFF;
fh[1] = cpu_to_be32(fh[1]);
fh[2] = ip->i_num.no_addr >> 32;
fh[2] = cpu_to_be32(fh[2]);
fh[3] = ip->i_num.no_addr & 0xFFFFFFFF;
fh[3] = cpu_to_be32(fh[3]);
*len = 4;
if (!connectable || inode == sb->s_root->d_inode)
return *len;
spin_lock(&dentry->d_lock);
inode = dentry->d_parent->d_inode;
ip = inode->u.generic_ip;
gfs2_inode_hold(ip);
spin_unlock(&dentry->d_lock);
fh[4] = ip->i_num.no_formal_ino >> 32;
fh[4] = cpu_to_be32(fh[4]);
fh[5] = ip->i_num.no_formal_ino & 0xFFFFFFFF;
fh[5] = cpu_to_be32(fh[5]);
fh[6] = ip->i_num.no_addr >> 32;
fh[6] = cpu_to_be32(fh[6]);
fh[7] = ip->i_num.no_addr & 0xFFFFFFFF;
fh[7] = cpu_to_be32(fh[7]);
*len = 8;
gfs2_inode_put(ip);
return *len;
}
struct get_name_filldir {
struct gfs2_inum inum;
char *name;
};
static int get_name_filldir(void *opaque, const char *name, unsigned int length,
uint64_t offset, struct gfs2_inum *inum,
unsigned int type)
{
struct get_name_filldir *gnfd = (struct get_name_filldir *)opaque;
if (!gfs2_inum_equal(inum, &gnfd->inum))
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;
uint64_t offset = 0;
int error;
if (!dir)
return -EINVAL;
if (!S_ISDIR(dir->i_mode) || !inode)
return -EINVAL;
dip = dir->u.generic_ip;
ip = inode->u.generic_ip;
*name = 0;
gnfd.inum = ip->i_num;
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, NULL);
if (!inode)
return ERR_PTR(-ENOENT);
if (IS_ERR(inode))
return ERR_PTR(PTR_ERR(inode));
dentry = d_alloc_anon(inode);
if (!dentry) {
iput(inode);
return ERR_PTR(-ENOMEM);
}
return dentry;
}
static struct dentry *gfs2_get_dentry(struct super_block *sb, void *inum_p)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
struct gfs2_inum *inum = (struct gfs2_inum *)inum_p;
struct gfs2_holder i_gh, ri_gh, rgd_gh;
struct gfs2_rgrpd *rgd;
struct gfs2_inode *ip;
struct inode *inode;
struct dentry *dentry;
int error;
/* System files? */
inode = gfs2_iget(sb, inum);
if (inode) {
ip = inode->u.generic_ip;
if (ip->i_num.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 | GL_LOCAL_EXCL,
&i_gh);
if (error)
return ERR_PTR(error);
error = gfs2_inode_get(i_gh.gh_gl, inum, NO_CREATE, &ip);
if (error)
goto fail;
if (ip)
goto out_ip;
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);
error = gfs2_inode_get(i_gh.gh_gl, inum, CREATE, &ip);
if (error)
goto fail;
error = gfs2_inode_refresh(ip);
if (error) {
gfs2_inode_put(ip);
goto fail;
}
out_ip:
error = -EIO;
if (ip->i_di.di_flags & GFS2_DIF_SYSTEM) {
gfs2_inode_put(ip);
goto fail;
}
gfs2_glock_dq_uninit(&i_gh);
inode = gfs2_ip2v(ip);
gfs2_inode_put(ip);
if (!inode)
return ERR_PTR(-ENOMEM);
out_inode:
dentry = d_alloc_anon(inode);
if (!dentry) {
iput(inode);
return ERR_PTR(-ENOMEM);
}
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);
}
struct export_operations gfs2_export_ops = {
.decode_fh = gfs2_decode_fh,
.encode_fh = gfs2_encode_fh,
.get_name = gfs2_get_name,
.get_parent = gfs2_get_parent,
.get_dentry = gfs2_get_dentry,
};