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DEFINITIONS
This source file includes following definitions.
- afs_inode_map_status
- afs_iget5_test
- afs_iget5_set
- afs_iget
- afs_zap_data
- afs_validate
- afs_getattr
- afs_clear_inode
- afs_setattr
/*
* Copyright (c) 2002 Red Hat, Inc. All rights reserved.
*
* This software may be freely redistributed under the terms of the
* GNU General Public License.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Authors: David Woodhouse <dwmw2@infradead.org>
* David Howells <dhowells@redhat.com>
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/sched.h>
#include "internal.h"
struct afs_iget_data {
struct afs_fid fid;
struct afs_volume *volume; /* volume on which resides */
};
/*
* map the AFS file status to the inode member variables
*/
static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key)
{
struct inode *inode = AFS_VNODE_TO_I(vnode);
_debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu",
vnode->status.type,
vnode->status.nlink,
(unsigned long long) vnode->status.size,
vnode->status.data_version,
vnode->status.mode);
switch (vnode->status.type) {
case AFS_FTYPE_FILE:
inode->i_mode = S_IFREG | vnode->status.mode;
inode->i_op = &afs_file_inode_operations;
inode->i_fop = &afs_file_operations;
break;
case AFS_FTYPE_DIR:
inode->i_mode = S_IFDIR | vnode->status.mode;
inode->i_op = &afs_dir_inode_operations;
inode->i_fop = &afs_dir_file_operations;
break;
case AFS_FTYPE_SYMLINK:
inode->i_mode = S_IFLNK | vnode->status.mode;
inode->i_op = &page_symlink_inode_operations;
break;
default:
printk("kAFS: AFS vnode with undefined type\n");
return -EBADMSG;
}
inode->i_nlink = vnode->status.nlink;
inode->i_uid = vnode->status.owner;
inode->i_gid = 0;
inode->i_size = vnode->status.size;
inode->i_ctime.tv_sec = vnode->status.mtime_server;
inode->i_ctime.tv_nsec = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime;
inode->i_blocks = 0;
inode->i_version = vnode->fid.unique;
inode->i_mapping->a_ops = &afs_fs_aops;
/* check to see whether a symbolic link is really a mountpoint */
if (vnode->status.type == AFS_FTYPE_SYMLINK) {
afs_mntpt_check_symlink(vnode, key);
if (test_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags)) {
inode->i_mode = S_IFDIR | vnode->status.mode;
inode->i_op = &afs_mntpt_inode_operations;
inode->i_fop = &afs_mntpt_file_operations;
}
}
return 0;
}
/*
* iget5() comparator
*/
static int afs_iget5_test(struct inode *inode, void *opaque)
{
struct afs_iget_data *data = opaque;
return inode->i_ino == data->fid.vnode &&
inode->i_version == data->fid.unique;
}
/*
* iget5() inode initialiser
*/
static int afs_iget5_set(struct inode *inode, void *opaque)
{
struct afs_iget_data *data = opaque;
struct afs_vnode *vnode = AFS_FS_I(inode);
inode->i_ino = data->fid.vnode;
inode->i_version = data->fid.unique;
vnode->fid = data->fid;
vnode->volume = data->volume;
return 0;
}
/*
* inode retrieval
*/
struct inode *afs_iget(struct super_block *sb, struct key *key,
struct afs_fid *fid, struct afs_file_status *status,
struct afs_callback *cb)
{
struct afs_iget_data data = { .fid = *fid };
struct afs_super_info *as;
struct afs_vnode *vnode;
struct inode *inode;
int ret;
_enter(",{%x:%u.%u},,", fid->vid, fid->vnode, fid->unique);
as = sb->s_fs_info;
data.volume = as->volume;
inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
&data);
if (!inode) {
_leave(" = -ENOMEM");
return ERR_PTR(-ENOMEM);
}
_debug("GOT INODE %p { vl=%x vn=%x, u=%x }",
inode, fid->vid, fid->vnode, fid->unique);
vnode = AFS_FS_I(inode);
/* deal with an existing inode */
if (!(inode->i_state & I_NEW)) {
_leave(" = %p", inode);
return inode;
}
#ifdef AFS_CACHING_SUPPORT
/* set up caching before reading the status, as fetch-status reads the
* first page of symlinks to see if they're really mntpts */
cachefs_acquire_cookie(vnode->volume->cache,
NULL,
vnode,
&vnode->cache);
#endif
if (!status) {
/* it's a remotely extant inode */
set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
ret = afs_vnode_fetch_status(vnode, NULL, key);
if (ret < 0)
goto bad_inode;
} else {
/* it's an inode we just created */
memcpy(&vnode->status, status, sizeof(vnode->status));
if (!cb) {
/* it's a symlink we just created (the fileserver
* didn't give us a callback) */
vnode->cb_version = 0;
vnode->cb_expiry = 0;
vnode->cb_type = 0;
vnode->cb_expires = get_seconds();
} else {
vnode->cb_version = cb->version;
vnode->cb_expiry = cb->expiry;
vnode->cb_type = cb->type;
vnode->cb_expires = vnode->cb_expiry + get_seconds();
}
}
ret = afs_inode_map_status(vnode, key);
if (ret < 0)
goto bad_inode;
/* success */
clear_bit(AFS_VNODE_UNSET, &vnode->flags);
inode->i_flags |= S_NOATIME;
unlock_new_inode(inode);
_leave(" = %p [CB { v=%u t=%u }]", inode, vnode->cb_version, vnode->cb_type);
return inode;
/* failure */
bad_inode:
iget_failed(inode);
_leave(" = %d [bad]", ret);
return ERR_PTR(ret);
}
/*
* mark the data attached to an inode as obsolete due to a write on the server
* - might also want to ditch all the outstanding writes and dirty pages
*/
void afs_zap_data(struct afs_vnode *vnode)
{
_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
/* nuke all the non-dirty pages that aren't locked, mapped or being
* written back in a regular file and completely discard the pages in a
* directory or symlink */
if (S_ISREG(vnode->vfs_inode.i_mode))
invalidate_remote_inode(&vnode->vfs_inode);
else
invalidate_inode_pages2(vnode->vfs_inode.i_mapping);
}
/*
* validate a vnode/inode
* - there are several things we need to check
* - parent dir data changes (rm, rmdir, rename, mkdir, create, link,
* symlink)
* - parent dir metadata changed (security changes)
* - dentry data changed (write, truncate)
* - dentry metadata changed (security changes)
*/
int afs_validate(struct afs_vnode *vnode, struct key *key)
{
int ret;
_enter("{v={%x:%u} fl=%lx},%x",
vnode->fid.vid, vnode->fid.vnode, vnode->flags,
key_serial(key));
if (vnode->cb_promised &&
!test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&
!test_bit(AFS_VNODE_MODIFIED, &vnode->flags) &&
!test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {
if (vnode->cb_expires < get_seconds() + 10) {
_debug("callback expired");
set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
} else {
goto valid;
}
}
if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
goto valid;
mutex_lock(&vnode->validate_lock);
/* if the promise has expired, we need to check the server again to get
* a new promise - note that if the (parent) directory's metadata was
* changed then the security may be different and we may no longer have
* access */
if (!vnode->cb_promised ||
test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags)) {
_debug("not promised");
ret = afs_vnode_fetch_status(vnode, NULL, key);
if (ret < 0)
goto error_unlock;
_debug("new promise [fl=%lx]", vnode->flags);
}
if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
_debug("file already deleted");
ret = -ESTALE;
goto error_unlock;
}
/* if the vnode's data version number changed then its contents are
* different */
if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags))
afs_zap_data(vnode);
clear_bit(AFS_VNODE_MODIFIED, &vnode->flags);
mutex_unlock(&vnode->validate_lock);
valid:
_leave(" = 0");
return 0;
error_unlock:
mutex_unlock(&vnode->validate_lock);
_leave(" = %d", ret);
return ret;
}
/*
* read the attributes of an inode
*/
int afs_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat)
{
struct inode *inode;
inode = dentry->d_inode;
_enter("{ ino=%lu v=%llu }", inode->i_ino,
(unsigned long long)inode->i_version);
generic_fillattr(inode, stat);
return 0;
}
/*
* clear an AFS inode
*/
void afs_clear_inode(struct inode *inode)
{
struct afs_permits *permits;
struct afs_vnode *vnode;
vnode = AFS_FS_I(inode);
_enter("{%x:%u.%d} v=%u x=%u t=%u }",
vnode->fid.vid,
vnode->fid.vnode,
vnode->fid.unique,
vnode->cb_version,
vnode->cb_expiry,
vnode->cb_type);
_debug("CLEAR INODE %p", inode);
ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode);
afs_give_up_callback(vnode);
if (vnode->server) {
spin_lock(&vnode->server->fs_lock);
rb_erase(&vnode->server_rb, &vnode->server->fs_vnodes);
spin_unlock(&vnode->server->fs_lock);
afs_put_server(vnode->server);
vnode->server = NULL;
}
ASSERT(list_empty(&vnode->writebacks));
ASSERT(!vnode->cb_promised);
#ifdef AFS_CACHING_SUPPORT
cachefs_relinquish_cookie(vnode->cache, 0);
vnode->cache = NULL;
#endif
mutex_lock(&vnode->permits_lock);
permits = vnode->permits;
rcu_assign_pointer(vnode->permits, NULL);
mutex_unlock(&vnode->permits_lock);
if (permits)
call_rcu(&permits->rcu, afs_zap_permits);
_leave("");
}
/*
* set the attributes of an inode
*/
int afs_setattr(struct dentry *dentry, struct iattr *attr)
{
struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
struct key *key;
int ret;
_enter("{%x:%u},{n=%s},%x",
vnode->fid.vid, vnode->fid.vnode, dentry->d_name.name,
attr->ia_valid);
if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID |
ATTR_MTIME))) {
_leave(" = 0 [unsupported]");
return 0;
}
/* flush any dirty data outstanding on a regular file */
if (S_ISREG(vnode->vfs_inode.i_mode)) {
filemap_write_and_wait(vnode->vfs_inode.i_mapping);
afs_writeback_all(vnode);
}
if (attr->ia_valid & ATTR_FILE) {
key = attr->ia_file->private_data;
} else {
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error;
}
}
ret = afs_vnode_setattr(vnode, key, attr);
if (!(attr->ia_valid & ATTR_FILE))
key_put(key);
error:
_leave(" = %d", ret);
return ret;
}