linux/fs/xfs/xfs_acl.c
Dave Chinner 2451337dd0 xfs: global error sign conversion
Convert all the errors the core XFs code to negative error signs
like the rest of the kernel and remove all the sign conversion we
do in the interface layers.

Errors for conversion (and comparison) found via searches like:

$ git grep " E" fs/xfs
$ git grep "return E" fs/xfs
$ git grep " E[A-Z].*;$" fs/xfs

Negation points found via searches like:

$ git grep "= -[a-z,A-Z]" fs/xfs
$ git grep "return -[a-z,A-D,F-Z]" fs/xfs
$ git grep " -[a-z].*;" fs/xfs

[ with some bits I missed from Brian Foster ]

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:58:08 +10:00

307 lines
6.4 KiB
C

/*
* Copyright (c) 2008, Christoph Hellwig
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_ag.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_acl.h"
#include "xfs_attr.h"
#include "xfs_trace.h"
#include <linux/slab.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>
/*
* Locking scheme:
* - all ACL updates are protected by inode->i_mutex, which is taken before
* calling into this file.
*/
STATIC struct posix_acl *
xfs_acl_from_disk(
struct xfs_acl *aclp,
int max_entries)
{
struct posix_acl_entry *acl_e;
struct posix_acl *acl;
struct xfs_acl_entry *ace;
unsigned int count, i;
count = be32_to_cpu(aclp->acl_cnt);
if (count > max_entries)
return ERR_PTR(-EFSCORRUPTED);
acl = posix_acl_alloc(count, GFP_KERNEL);
if (!acl)
return ERR_PTR(-ENOMEM);
for (i = 0; i < count; i++) {
acl_e = &acl->a_entries[i];
ace = &aclp->acl_entry[i];
/*
* The tag is 32 bits on disk and 16 bits in core.
*
* Because every access to it goes through the core
* format first this is not a problem.
*/
acl_e->e_tag = be32_to_cpu(ace->ae_tag);
acl_e->e_perm = be16_to_cpu(ace->ae_perm);
switch (acl_e->e_tag) {
case ACL_USER:
acl_e->e_uid = xfs_uid_to_kuid(be32_to_cpu(ace->ae_id));
break;
case ACL_GROUP:
acl_e->e_gid = xfs_gid_to_kgid(be32_to_cpu(ace->ae_id));
break;
case ACL_USER_OBJ:
case ACL_GROUP_OBJ:
case ACL_MASK:
case ACL_OTHER:
break;
default:
goto fail;
}
}
return acl;
fail:
posix_acl_release(acl);
return ERR_PTR(-EINVAL);
}
STATIC void
xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
{
const struct posix_acl_entry *acl_e;
struct xfs_acl_entry *ace;
int i;
aclp->acl_cnt = cpu_to_be32(acl->a_count);
for (i = 0; i < acl->a_count; i++) {
ace = &aclp->acl_entry[i];
acl_e = &acl->a_entries[i];
ace->ae_tag = cpu_to_be32(acl_e->e_tag);
switch (acl_e->e_tag) {
case ACL_USER:
ace->ae_id = cpu_to_be32(xfs_kuid_to_uid(acl_e->e_uid));
break;
case ACL_GROUP:
ace->ae_id = cpu_to_be32(xfs_kgid_to_gid(acl_e->e_gid));
break;
default:
ace->ae_id = cpu_to_be32(ACL_UNDEFINED_ID);
break;
}
ace->ae_perm = cpu_to_be16(acl_e->e_perm);
}
}
struct posix_acl *
xfs_get_acl(struct inode *inode, int type)
{
struct xfs_inode *ip = XFS_I(inode);
struct posix_acl *acl = NULL;
struct xfs_acl *xfs_acl;
unsigned char *ea_name;
int error;
int len;
trace_xfs_get_acl(ip);
switch (type) {
case ACL_TYPE_ACCESS:
ea_name = SGI_ACL_FILE;
break;
case ACL_TYPE_DEFAULT:
ea_name = SGI_ACL_DEFAULT;
break;
default:
BUG();
}
/*
* If we have a cached ACLs value just return it, not need to
* go out to the disk.
*/
len = XFS_ACL_MAX_SIZE(ip->i_mount);
xfs_acl = kmem_zalloc_large(len, KM_SLEEP);
if (!xfs_acl)
return ERR_PTR(-ENOMEM);
error = xfs_attr_get(ip, ea_name, (unsigned char *)xfs_acl,
&len, ATTR_ROOT);
if (error) {
/*
* If the attribute doesn't exist make sure we have a negative
* cache entry, for any other error assume it is transient and
* leave the cache entry as ACL_NOT_CACHED.
*/
if (error == -ENOATTR)
goto out_update_cache;
goto out;
}
acl = xfs_acl_from_disk(xfs_acl, XFS_ACL_MAX_ENTRIES(ip->i_mount));
if (IS_ERR(acl))
goto out;
out_update_cache:
set_cached_acl(inode, type, acl);
out:
kmem_free(xfs_acl);
return acl;
}
STATIC int
__xfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
{
struct xfs_inode *ip = XFS_I(inode);
unsigned char *ea_name;
int error;
switch (type) {
case ACL_TYPE_ACCESS:
ea_name = SGI_ACL_FILE;
break;
case ACL_TYPE_DEFAULT:
if (!S_ISDIR(inode->i_mode))
return acl ? -EACCES : 0;
ea_name = SGI_ACL_DEFAULT;
break;
default:
return -EINVAL;
}
if (acl) {
struct xfs_acl *xfs_acl;
int len = XFS_ACL_MAX_SIZE(ip->i_mount);
xfs_acl = kmem_zalloc_large(len, KM_SLEEP);
if (!xfs_acl)
return -ENOMEM;
xfs_acl_to_disk(xfs_acl, acl);
/* subtract away the unused acl entries */
len -= sizeof(struct xfs_acl_entry) *
(XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
error = xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
len, ATTR_ROOT);
kmem_free(xfs_acl);
} else {
/*
* A NULL ACL argument means we want to remove the ACL.
*/
error = xfs_attr_remove(ip, ea_name, ATTR_ROOT);
/*
* If the attribute didn't exist to start with that's fine.
*/
if (error == -ENOATTR)
error = 0;
}
if (!error)
set_cached_acl(inode, type, acl);
return error;
}
static int
xfs_set_mode(struct inode *inode, umode_t mode)
{
int error = 0;
if (mode != inode->i_mode) {
struct iattr iattr;
iattr.ia_valid = ATTR_MODE | ATTR_CTIME;
iattr.ia_mode = mode;
iattr.ia_ctime = current_fs_time(inode->i_sb);
error = xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
}
return error;
}
static int
xfs_acl_exists(struct inode *inode, unsigned char *name)
{
int len = XFS_ACL_MAX_SIZE(XFS_M(inode->i_sb));
return (xfs_attr_get(XFS_I(inode), name, NULL, &len,
ATTR_ROOT|ATTR_KERNOVAL) == 0);
}
int
posix_acl_access_exists(struct inode *inode)
{
return xfs_acl_exists(inode, SGI_ACL_FILE);
}
int
posix_acl_default_exists(struct inode *inode)
{
if (!S_ISDIR(inode->i_mode))
return 0;
return xfs_acl_exists(inode, SGI_ACL_DEFAULT);
}
int
xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
int error = 0;
if (!acl)
goto set_acl;
error = -E2BIG;
if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
return error;
if (type == ACL_TYPE_ACCESS) {
umode_t mode = inode->i_mode;
error = posix_acl_equiv_mode(acl, &mode);
if (error <= 0) {
acl = NULL;
if (error < 0)
return error;
}
error = xfs_set_mode(inode, mode);
if (error)
return error;
}
set_acl:
return __xfs_set_acl(inode, type, acl);
}