kernel-ark/fs/gfs2/eaops.c
Steven Whitehouse f057f6cdf6 GFS2: Merge lock_dlm module into GFS2
This is the big patch that I've been working on for some time
now. There are many reasons for wanting to make this change
such as:
 o Reducing overhead by eliminating duplicated fields between structures
 o Simplifcation of the code (reduces the code size by a fair bit)
 o The locking interface is now the DLM interface itself as proposed
   some time ago.
 o Fewer lookups of glocks when processing replies from the DLM
 o Fewer memory allocations/deallocations for each glock
 o Scope to do further optimisations in the future (but this patch is
   more than big enough for now!)

Please note that (a) this patch relates to the lock_dlm module and
not the DLM itself, that is still a separate module; and (b) that
we retain the ability to build GFS2 as a standalone single node
filesystem with out requiring the DLM.

This patch needs a lot of testing, hence my keeping it I restarted
my -git tree after the last merge window. That way, this has the maximum
exposure before its merged. This is (modulo a few minor bug fixes) the
same patch that I've been posting on and off the the last three months
and its passed a number of different tests so far.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-03-24 11:21:14 +00:00

158 lines
3.8 KiB
C

/*
* 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/capability.h>
#include <linux/xattr.h>
#include <linux/gfs2_ondisk.h>
#include <asm/uaccess.h>
#include "gfs2.h"
#include "incore.h"
#include "acl.h"
#include "eaops.h"
#include "eattr.h"
#include "util.h"
/**
* gfs2_ea_name2type - get the type of the ea, and truncate type from the name
* @namep: ea name, possibly with type appended
*
* Returns: GFS2_EATYPE_XXX
*/
unsigned int gfs2_ea_name2type(const char *name, const char **truncated_name)
{
unsigned int type;
if (strncmp(name, "system.", 7) == 0) {
type = GFS2_EATYPE_SYS;
if (truncated_name)
*truncated_name = name + sizeof("system.") - 1;
} else if (strncmp(name, "user.", 5) == 0) {
type = GFS2_EATYPE_USR;
if (truncated_name)
*truncated_name = name + sizeof("user.") - 1;
} else if (strncmp(name, "security.", 9) == 0) {
type = GFS2_EATYPE_SECURITY;
if (truncated_name)
*truncated_name = name + sizeof("security.") - 1;
} else {
type = GFS2_EATYPE_UNUSED;
if (truncated_name)
*truncated_name = NULL;
}
return type;
}
static int system_eo_get(struct gfs2_inode *ip, struct gfs2_ea_request *er)
{
if (!GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) &&
!GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len) &&
!capable(CAP_SYS_ADMIN))
return -EPERM;
if (GFS2_SB(&ip->i_inode)->sd_args.ar_posix_acl == 0 &&
(GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len) ||
GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)))
return -EOPNOTSUPP;
return gfs2_ea_get_i(ip, er);
}
static int system_eo_set(struct gfs2_inode *ip, struct gfs2_ea_request *er)
{
int remove = 0;
int error;
if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
if (!(er->er_flags & GFS2_ERF_MODE)) {
er->er_mode = ip->i_inode.i_mode;
er->er_flags |= GFS2_ERF_MODE;
}
error = gfs2_acl_validate_set(ip, 1, er,
&remove, &er->er_mode);
if (error)
return error;
error = gfs2_ea_set_i(ip, er);
if (error)
return error;
if (remove)
gfs2_ea_remove_i(ip, er);
return 0;
} else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
error = gfs2_acl_validate_set(ip, 0, er,
&remove, NULL);
if (error)
return error;
if (!remove)
error = gfs2_ea_set_i(ip, er);
else {
error = gfs2_ea_remove_i(ip, er);
if (error == -ENODATA)
error = 0;
}
return error;
}
return -EPERM;
}
static int system_eo_remove(struct gfs2_inode *ip, struct gfs2_ea_request *er)
{
if (GFS2_ACL_IS_ACCESS(er->er_name, er->er_name_len)) {
int error = gfs2_acl_validate_remove(ip, 1);
if (error)
return error;
} else if (GFS2_ACL_IS_DEFAULT(er->er_name, er->er_name_len)) {
int error = gfs2_acl_validate_remove(ip, 0);
if (error)
return error;
} else
return -EPERM;
return gfs2_ea_remove_i(ip, er);
}
static const struct gfs2_eattr_operations gfs2_user_eaops = {
.eo_get = gfs2_ea_get_i,
.eo_set = gfs2_ea_set_i,
.eo_remove = gfs2_ea_remove_i,
.eo_name = "user",
};
const struct gfs2_eattr_operations gfs2_system_eaops = {
.eo_get = system_eo_get,
.eo_set = system_eo_set,
.eo_remove = system_eo_remove,
.eo_name = "system",
};
static const struct gfs2_eattr_operations gfs2_security_eaops = {
.eo_get = gfs2_ea_get_i,
.eo_set = gfs2_ea_set_i,
.eo_remove = gfs2_ea_remove_i,
.eo_name = "security",
};
const struct gfs2_eattr_operations *gfs2_ea_ops[] = {
NULL,
&gfs2_user_eaops,
&gfs2_system_eaops,
&gfs2_security_eaops,
};