Пример #1
0
/*
 * handle remote file deletion by discarding the callback promise
 */
static void afs_vnode_deleted_remotely(struct afs_vnode *vnode)
{
	struct afs_server *server;

	_enter("{%p}", vnode->server);

	set_bit(AFS_VNODE_DELETED, &vnode->flags);

	server = vnode->server;
	if (server) {
		if (vnode->cb_promised) {
			spin_lock(&server->cb_lock);
			if (vnode->cb_promised) {
				rb_erase(&vnode->cb_promise,
					 &server->cb_promises);
				vnode->cb_promised = false;
			}
			spin_unlock(&server->cb_lock);
		}

		spin_lock(&server->fs_lock);
		rb_erase(&vnode->server_rb, &server->fs_vnodes);
		spin_unlock(&server->fs_lock);

		vnode->server = NULL;
		afs_put_server(server);
	} else {
		ASSERT(!vnode->cb_promised);
	}

	_leave("");
}
Пример #2
0
/*
 * handle a callback timing out
 * TODO: retain a ref to vnode struct for an outstanding callback timeout
 */
static void afs_vnode_cb_timed_out(struct afs_timer *timer)
{
	struct afs_server *oldserver;
	struct afs_vnode *vnode;

	vnode = list_entry(timer, struct afs_vnode, cb_timeout);

	_enter("%p", vnode);

	/* set the changed flag in the vnode and release the server */
	spin_lock(&vnode->lock);

	oldserver = xchg(&vnode->cb_server, NULL);
	if (oldserver) {
		vnode->flags |= AFS_VNODE_CHANGED;

		spin_lock(&afs_cb_hash_lock);
		list_del_init(&vnode->cb_hash_link);
		spin_unlock(&afs_cb_hash_lock);

		spin_lock(&oldserver->cb_lock);
		list_del_init(&vnode->cb_link);
		spin_unlock(&oldserver->cb_lock);
	}

	spin_unlock(&vnode->lock);

	afs_put_server(oldserver);

	_leave("");
} /* end afs_vnode_cb_timed_out() */
Пример #3
0
Файл: rxrpc.c Проект: krzk/linux
/*
 * Dispose of a reference on a call.
 */
void afs_put_call(struct afs_call *call)
{
	struct afs_net *net = call->net;
	int n = atomic_dec_return(&call->usage);
	int o = atomic_read(&net->nr_outstanding_calls);

	trace_afs_call(call, afs_call_trace_put, n + 1, o,
		       __builtin_return_address(0));

	ASSERTCMP(n, >=, 0);
	if (n == 0) {
		ASSERT(!work_pending(&call->async_work));
		ASSERT(call->type->name != NULL);

		if (call->rxcall) {
			rxrpc_kernel_end_call(net->socket, call->rxcall);
			call->rxcall = NULL;
		}
		if (call->type->destructor)
			call->type->destructor(call);

		afs_put_server(call->net, call->cm_server);
		afs_put_cb_interest(call->net, call->cbi);
		kfree(call->request);

		trace_afs_call(call, afs_call_trace_free, 0, o,
			       __builtin_return_address(0));
		kfree(call);

		o = atomic_dec_return(&net->nr_outstanding_calls);
		if (o == 0)
			wake_up_var(&net->nr_outstanding_calls);
	}
}
Пример #4
0
/*
 * finish off updating the recorded status of a file
 * - starts callback expiry timer
 * - adds to server's callback list
 */
void afs_vnode_finalise_status_update(afs_vnode_t *vnode, afs_server_t *server, int ret)
{
	afs_server_t *oldserver = NULL;

	_enter("%p,%p,%d",vnode,server,ret);

	spin_lock(&vnode->lock);

	vnode->flags &= ~AFS_VNODE_CHANGED;

	if (ret==0) {
		/* adjust the callback timeout appropriately */
		afs_kafstimod_add_timer(&vnode->cb_timeout,vnode->cb_expiry*HZ);

		spin_lock(&afs_cb_hash_lock);
		list_del(&vnode->cb_hash_link);
		list_add_tail(&vnode->cb_hash_link,&afs_cb_hash(server,&vnode->fid));
		spin_unlock(&afs_cb_hash_lock);

		/* swap ref to old callback server with that for new callback server */
		oldserver = xchg(&vnode->cb_server,server);
		if (oldserver!=server) {
			if (oldserver) {
				spin_lock(&oldserver->cb_lock);
				list_del_init(&vnode->cb_link);
				spin_unlock(&oldserver->cb_lock);
			}

			afs_get_server(server);
			spin_lock(&server->cb_lock);
			list_add_tail(&vnode->cb_link,&server->cb_promises);
			spin_unlock(&server->cb_lock);
		}
		else {
			/* same server */
			oldserver = NULL;
		}
	}
	else if (ret==-ENOENT) {
		/* the file was deleted - clear the callback timeout */
		oldserver = xchg(&vnode->cb_server,NULL);
		afs_kafstimod_del_timer(&vnode->cb_timeout);

		_debug("got NOENT from server - marking file deleted");
		vnode->flags |= AFS_VNODE_DELETED;
	}

	vnode->update_cnt--;

	spin_unlock(&vnode->lock);

	wake_up_all(&vnode->update_waitq);

	afs_put_server(oldserver);

	_leave("");

} /* end afs_vnode_finalise_status_update() */
Пример #5
0
/*
 * clean up a cache manager call
 */
static void afs_cm_destructor(struct afs_call *call)
{
	_enter("");

	afs_put_server(call->server);
	call->server = NULL;
	kfree(call->buffer);
	call->buffer = NULL;
}
Пример #6
0
void afs_put_serverlist(struct afs_net *net, struct afs_server_list *slist)
{
	int i;

	if (slist && refcount_dec_and_test(&slist->usage)) {
		for (i = 0; i < slist->nr_servers; i++) {
			afs_put_cb_interest(net, slist->servers[i].cb_interest);
			afs_put_server(net, slist->servers[i].server);
		}
		kfree(slist);
	}
}
Пример #7
0
/*
 * fetch file data from the volume
 * - TODO implement caching
 */
int afs_vnode_fetch_data(struct afs_vnode *vnode, struct key *key,
			 off_t offset, size_t length, struct page *page)
{
	struct afs_server *server;
	int ret;

	_enter("%s{%x:%u.%u},%x,,,",
	       vnode->volume->vlocation->vldb.name,
	       vnode->fid.vid,
	       vnode->fid.vnode,
	       vnode->fid.unique,
	       key_serial(key));

	/* this op will fetch the status */
	spin_lock(&vnode->lock);
	vnode->update_cnt++;
	spin_unlock(&vnode->lock);

	/* merge in AFS status fetches and clear outstanding callback on this
	 * vnode */
	do {
		/* pick a server to query */
		server = afs_volume_pick_fileserver(vnode);
		if (IS_ERR(server))
			goto no_server;

		_debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));

		ret = afs_fs_fetch_data(server, key, vnode, offset, length,
					page, &afs_sync_call);

	} while (!afs_volume_release_fileserver(vnode, server, ret));

	/* adjust the flags */
	if (ret == 0) {
		afs_vnode_finalise_status_update(vnode, server);
		afs_put_server(server);
	} else {
		afs_vnode_status_update_failed(vnode, ret);
	}

	_leave(" = %d", ret);
	return ret;

no_server:
	spin_lock(&vnode->lock);
	vnode->update_cnt--;
	ASSERTCMP(vnode->update_cnt, >=, 0);
	spin_unlock(&vnode->lock);
	return PTR_ERR(server);
}
Пример #8
0
/*
 * remove a file or directory
 */
int afs_vnode_remove(struct afs_vnode *vnode, struct key *key, const char *name,
		     bool isdir)
{
	struct afs_server *server;
	int ret;

	_enter("%s{%x:%u.%u},%x,%s",
	       vnode->volume->vlocation->vldb.name,
	       vnode->fid.vid,
	       vnode->fid.vnode,
	       vnode->fid.unique,
	       key_serial(key),
	       name);

	/* this op will fetch the status on the directory we're removing from */
	spin_lock(&vnode->lock);
	vnode->update_cnt++;
	spin_unlock(&vnode->lock);

	do {
		/* pick a server to query */
		server = afs_volume_pick_fileserver(vnode);
		if (IS_ERR(server))
			goto no_server;

		_debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));

		ret = afs_fs_remove(server, key, vnode, name, isdir,
				    &afs_sync_call);

	} while (!afs_volume_release_fileserver(vnode, server, ret));

	/* adjust the flags */
	if (ret == 0) {
		afs_vnode_finalise_status_update(vnode, server);
		afs_put_server(server);
	} else {
		afs_vnode_status_update_failed(vnode, ret);
	}

	_leave(" = %d [cnt %d]", ret, vnode->update_cnt);
	return ret;

no_server:
	spin_lock(&vnode->lock);
	vnode->update_cnt--;
	ASSERTCMP(vnode->update_cnt, >=, 0);
	spin_unlock(&vnode->lock);
	_leave(" = %ld [cnt %d]", PTR_ERR(server), vnode->update_cnt);
	return PTR_ERR(server);
}
Пример #9
0
/*
 * clear an AFS inode
 */
void afs_evict_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);

	truncate_inode_pages_final(&inode->i_data);
	clear_inode(inode);

	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 CONFIG_AFS_FSCACHE
	fscache_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("");
}
Пример #10
0
/*
 * insert a vnode into the backing server's vnode tree
 */
static void afs_install_vnode(struct afs_vnode *vnode,
			      struct afs_server *server)
{
	struct afs_server *old_server = vnode->server;
	struct afs_vnode *xvnode;
	struct rb_node *parent, **p;

	_enter("%p,%p", vnode, server);

	if (old_server) {
		spin_lock(&old_server->fs_lock);
		rb_erase(&vnode->server_rb, &old_server->fs_vnodes);
		spin_unlock(&old_server->fs_lock);
	}

	afs_get_server(server);
	vnode->server = server;
	afs_put_server(old_server);

	/* insert into the server's vnode tree in FID order */
	spin_lock(&server->fs_lock);

	parent = NULL;
	p = &server->fs_vnodes.rb_node;
	while (*p) {
		parent = *p;
		xvnode = rb_entry(parent, struct afs_vnode, server_rb);
		if (vnode->fid.vid < xvnode->fid.vid)
			p = &(*p)->rb_left;
		else if (vnode->fid.vid > xvnode->fid.vid)
			p = &(*p)->rb_right;
		else if (vnode->fid.vnode < xvnode->fid.vnode)
			p = &(*p)->rb_left;
		else if (vnode->fid.vnode > xvnode->fid.vnode)
			p = &(*p)->rb_right;
		else if (vnode->fid.unique < xvnode->fid.unique)
			p = &(*p)->rb_left;
		else if (vnode->fid.unique > xvnode->fid.unique)
			p = &(*p)->rb_right;
		else
			BUG(); /* can't happen unless afs_iget() malfunctions */
	}

	rb_link_node(&vnode->server_rb, parent, p);
	rb_insert_color(&vnode->server_rb, &server->fs_vnodes);

	spin_unlock(&server->fs_lock);
	_leave("");
}
Пример #11
0
/*
 * clean up a cache manager call
 */
static void afs_cm_destructor(struct afs_call *call)
{
	_enter("");

	/* Break the callbacks here so that we do it after the final ACK is
	 * received.  The step number here must match the final number in
	 * afs_deliver_cb_callback().
	 */
	if (call->unmarshall == 5) {
		ASSERT(call->server && call->count && call->request);
		afs_break_callbacks(call->server, call->count, call->request);
	}

	afs_put_server(call->server);
	call->server = NULL;
	kfree(call->buffer);
	call->buffer = NULL;
}
Пример #12
0
/*
 * finish off updating the recorded status of a file after a successful
 * operation completion
 * - starts callback expiry timer
 * - adds to server's callback list
 */
void afs_vnode_finalise_status_update(struct afs_vnode *vnode,
				      struct afs_server *server)
{
	struct afs_server *oldserver = NULL;

	_enter("%p,%p", vnode, server);

	spin_lock(&vnode->lock);
	clear_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
	afs_vnode_note_promise(vnode, server);
	vnode->update_cnt--;
	ASSERTCMP(vnode->update_cnt, >=, 0);
	spin_unlock(&vnode->lock);

	wake_up_all(&vnode->update_waitq);
	afs_put_server(oldserver);
	_leave("");
}
Пример #13
0
/*
 * destroy a volume record
 */
void afs_put_volume(struct afs_volume *volume)
{
	struct afs_vlocation *vlocation;
	int loop;

	if (!volume)
		return;

	_enter("%p", volume);

	ASSERTCMP(atomic_read(&volume->usage), >, 0);

	vlocation = volume->vlocation;

	/* to prevent a race, the decrement and the dequeue must be effectively
	 * atomic */
	down_write(&vlocation->cell->vl_sem);

	if (likely(!atomic_dec_and_test(&volume->usage))) {
		up_write(&vlocation->cell->vl_sem);
		_leave("");
		return;
	}

	vlocation->vols[volume->type] = NULL;

	up_write(&vlocation->cell->vl_sem);

	/* finish cleaning up the volume */
#ifdef CONFIG_AFS_FSCACHE
	fscache_relinquish_cookie(volume->cache, 0);
#endif
	afs_put_vlocation(vlocation);

	for (loop = volume->nservers - 1; loop >= 0; loop--)
		afs_put_server(volume->servers[loop]);

	bdi_destroy(&volume->bdi);
	kfree(volume);

	_leave(" [destroyed]");
}
Пример #14
0
/*
 * break any outstanding callback on a vnode
 * - only relevent to server that issued it
 */
int afs_vnode_give_up_callback(struct afs_vnode *vnode)
{
	struct afs_server *server;
	int ret;

	_enter("%s,{%u,%u,%u}",
	       vnode->volume->vlocation->vldb.name,
	       vnode->fid.vid,
	       vnode->fid.vnode,
	       vnode->fid.unique);

	spin_lock(&afs_cb_hash_lock);
	list_del_init(&vnode->cb_hash_link);
	spin_unlock(&afs_cb_hash_lock);

	/* set the changed flag in the vnode and release the server */
	spin_lock(&vnode->lock);

	afs_kafstimod_del_timer(&vnode->cb_timeout);

	server = xchg(&vnode->cb_server, NULL);
	if (server) {
		vnode->flags |= AFS_VNODE_CHANGED;

		spin_lock(&server->cb_lock);
		list_del_init(&vnode->cb_link);
		spin_unlock(&server->cb_lock);
	}

	spin_unlock(&vnode->lock);

	ret = 0;
	if (server) {
		ret = afs_rxfs_give_up_callback(server, vnode);
		afs_put_server(server);
	}

	_leave(" = %d", ret);
	return ret;
} /* end afs_vnode_give_up_callback() */
Пример #15
0
/*
 * release a server after use
 * - releases the ref on the server struct that was acquired by picking
 * - records result of using a particular server to access a volume
 * - return 0 to try again, 1 if okay or to issue error
 * - the caller must release the server struct if result was 0
 */
int afs_volume_release_fileserver(struct afs_vnode *vnode,
				  struct afs_server *server,
				  int result)
{
	struct afs_volume *volume = vnode->volume;
	unsigned loop;

	_enter("%s,%08x,%d",
	       volume->vlocation->vldb.name, ntohl(server->addr.s_addr),
	       result);

	switch (result) {
		/* success */
	case 0:
		server->fs_act_jif = jiffies;
		server->fs_state = 0;
		_leave("");
		return 1;

		/* the fileserver denied all knowledge of the volume */
	case -ENOMEDIUM:
		server->fs_act_jif = jiffies;
		down_write(&volume->server_sem);

		/* firstly, find where the server is in the active list (if it
		 * is) */
		for (loop = 0; loop < volume->nservers; loop++)
			if (volume->servers[loop] == server)
				goto present;

		/* no longer there - may have been discarded by another op */
		goto try_next_server_upw;

	present:
		volume->nservers--;
		memmove(&volume->servers[loop],
			&volume->servers[loop + 1],
			sizeof(volume->servers[loop]) *
			(volume->nservers - loop));
		volume->servers[volume->nservers] = NULL;
		afs_put_server(server);
		volume->rjservers++;

		if (volume->nservers > 0)
			/* another server might acknowledge its existence */
			goto try_next_server_upw;

		/* handle the case where all the fileservers have rejected the
		 * volume
		 * - TODO: try asking the fileservers for volume information
		 * - TODO: contact the VL server again to see if the volume is
		 *         no longer registered
		 */
		up_write(&volume->server_sem);
		afs_put_server(server);
		_leave(" [completely rejected]");
		return 1;

		/* problem reaching the server */
	case -ENETUNREACH:
	case -EHOSTUNREACH:
	case -ECONNREFUSED:
	case -ETIME:
	case -ETIMEDOUT:
	case -EREMOTEIO:
		/* mark the server as dead
		 * TODO: vary dead timeout depending on error
		 */
		spin_lock(&server->fs_lock);
		if (!server->fs_state) {
			server->fs_dead_jif = jiffies + HZ * 10;
			server->fs_state = result;
			printk("kAFS: SERVER DEAD state=%d\n", result);
		}
		spin_unlock(&server->fs_lock);
		goto try_next_server;

		/* miscellaneous error */
	default:
		server->fs_act_jif = jiffies;
	case -ENOMEM:
	case -ENONET:
		/* tell the caller to accept the result */
		afs_put_server(server);
		_leave(" [local failure]");
		return 1;
	}

	/* tell the caller to loop around and try the next server */
try_next_server_upw:
	up_write(&volume->server_sem);
try_next_server:
	afs_put_server(server);
	_leave(" [try next server]");
	return 0;
}
Пример #16
0
/*
 * create a regular file on an AFS filesystem
 */
static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
		      bool excl)
{
	struct afs_file_status status;
	struct afs_callback cb;
	struct afs_server *server;
	struct afs_vnode *dvnode, *vnode;
	struct afs_fid fid;
	struct inode *inode;
	struct key *key;
	int ret;

	dvnode = AFS_FS_I(dir);

	_enter("{%x:%u},{%pd},%ho,",
	       dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);

	key = afs_request_key(dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	mode |= S_IFREG;
	ret = afs_vnode_create(dvnode, key, dentry->d_name.name,
			       mode, &fid, &status, &cb, &server);
	if (ret < 0)
		goto create_error;

	inode = afs_iget(dir->i_sb, key, &fid, &status, &cb);
	if (IS_ERR(inode)) {
		/* ENOMEM at a really inconvenient time - just abandon the new
		 * directory on the server */
		ret = PTR_ERR(inode);
		goto iget_error;
	}

	/* apply the status report we've got for the new vnode */
	vnode = AFS_FS_I(inode);
	spin_lock(&vnode->lock);
	vnode->update_cnt++;
	spin_unlock(&vnode->lock);
	afs_vnode_finalise_status_update(vnode, server);
	afs_put_server(server);

	d_instantiate(dentry, inode);
	if (d_unhashed(dentry)) {
		_debug("not hashed");
		d_rehash(dentry);
	}
	key_put(key);
	_leave(" = 0");
	return 0;

iget_error:
	afs_put_server(server);
create_error:
	key_put(key);
error:
	d_drop(dentry);
	_leave(" = %d", ret);
	return ret;
}
Пример #17
0
/*
 * Build a server list from a VLDB record.
 */
struct afs_server_list *afs_alloc_server_list(struct afs_cell *cell,
					      struct key *key,
					      struct afs_vldb_entry *vldb,
					      u8 type_mask)
{
	struct afs_server_list *slist;
	struct afs_server *server;
	int ret = -ENOMEM, nr_servers = 0, i, j;

	for (i = 0; i < vldb->nr_servers; i++)
		if (vldb->fs_mask[i] & type_mask)
			nr_servers++;

	slist = kzalloc(struct_size(slist, servers, nr_servers), GFP_KERNEL);
	if (!slist)
		goto error;

	refcount_set(&slist->usage, 1);
	rwlock_init(&slist->lock);

	/* Make sure a records exists for each server in the list. */
	for (i = 0; i < vldb->nr_servers; i++) {
		if (!(vldb->fs_mask[i] & type_mask))
			continue;

		server = afs_lookup_server(cell, key, &vldb->fs_server[i]);
		if (IS_ERR(server)) {
			ret = PTR_ERR(server);
			if (ret == -ENOENT ||
			    ret == -ENOMEDIUM)
				continue;
			goto error_2;
		}

		/* Insertion-sort by UUID */
		for (j = 0; j < slist->nr_servers; j++)
			if (memcmp(&slist->servers[j].server->uuid,
				   &server->uuid,
				   sizeof(server->uuid)) >= 0)
				break;
		if (j < slist->nr_servers) {
			if (slist->servers[j].server == server) {
				afs_put_server(cell->net, server);
				continue;
			}

			memmove(slist->servers + j + 1,
				slist->servers + j,
				(slist->nr_servers - j) * sizeof(struct afs_server_entry));
		}

		slist->servers[j].server = server;
		slist->nr_servers++;
	}

	if (slist->nr_servers == 0) {
		ret = -EDESTADDRREQ;
		goto error_2;
	}

	return slist;

error_2:
	afs_put_serverlist(cell->net, slist);
error:
	return ERR_PTR(ret);
}
Пример #18
0
/*
 * create a symlink in an AFS filesystem
 */
static int afs_symlink(struct inode *dir, struct dentry *dentry,
		       const char *content)
{
	struct afs_file_status status;
	struct afs_server *server;
	struct afs_vnode *dvnode, *vnode;
	struct afs_fid fid;
	struct inode *inode;
	struct key *key;
	int ret;

	dvnode = AFS_FS_I(dir);

	_enter("{%x:%u},{%s},%s",
	       dvnode->fid.vid, dvnode->fid.vnode, dentry->d_name.name,
	       content);

	ret = -ENAMETOOLONG;
	if (dentry->d_name.len >= AFSNAMEMAX)
		goto error;

	ret = -EINVAL;
	if (strlen(content) >= AFSPATHMAX)
		goto error;

	key = afs_request_key(dvnode->volume->cell);
	if (IS_ERR(key)) {
		ret = PTR_ERR(key);
		goto error;
	}

	ret = afs_vnode_symlink(dvnode, key, dentry->d_name.name, content,
				&fid, &status, &server);
	if (ret < 0)
		goto create_error;

	inode = afs_iget(dir->i_sb, key, &fid, &status, NULL);
	if (IS_ERR(inode)) {
		/* ENOMEM at a really inconvenient time - just abandon the new
		 * directory on the server */
		ret = PTR_ERR(inode);
		goto iget_error;
	}

	/* apply the status report we've got for the new vnode */
	vnode = AFS_FS_I(inode);
	spin_lock(&vnode->lock);
	vnode->update_cnt++;
	spin_unlock(&vnode->lock);
	afs_vnode_finalise_status_update(vnode, server);
	afs_put_server(server);

	d_instantiate(dentry, inode);
	if (d_unhashed(dentry)) {
		_debug("not hashed");
		d_rehash(dentry);
	}
	key_put(key);
	_leave(" = 0");
	return 0;

iget_error:
	afs_put_server(server);
create_error:
	key_put(key);
error:
	d_drop(dentry);
	_leave(" = %d", ret);
	return ret;
}
Пример #19
0
/*
 * lookup a volume by name
 * - this can be one of the following:
 *	"%[cell:]volume[.]"		R/W volume
 *	"#[cell:]volume[.]"		R/O or R/W volume (rwparent=0),
 *					 or R/W (rwparent=1) volume
 *	"%[cell:]volume.readonly"	R/O volume
 *	"#[cell:]volume.readonly"	R/O volume
 *	"%[cell:]volume.backup"		Backup volume
 *	"#[cell:]volume.backup"		Backup volume
 *
 * The cell name is optional, and defaults to the current cell.
 *
 * See "The Rules of Mount Point Traversal" in Chapter 5 of the AFS SysAdmin
 * Guide
 * - Rule 1: Explicit type suffix forces access of that type or nothing
 *           (no suffix, then use Rule 2 & 3)
 * - Rule 2: If parent volume is R/O, then mount R/O volume by preference, R/W
 *           if not available
 * - Rule 3: If parent volume is R/W, then only mount R/W volume unless
 *           explicitly told otherwise
 */
struct afs_volume *afs_volume_lookup(struct afs_mount_params *params)
{
	struct afs_vlocation *vlocation = NULL;
	struct afs_volume *volume = NULL;
	struct afs_server *server = NULL;
	char srvtmask;
	int ret, loop;

	_enter("{%*.*s,%d}",
	       params->volnamesz, params->volnamesz, params->volname, params->rwpath);

	/* lookup the volume location record */
	vlocation = afs_vlocation_lookup(params->cell, params->key,
					 params->volname, params->volnamesz);
	if (IS_ERR(vlocation)) {
		ret = PTR_ERR(vlocation);
		vlocation = NULL;
		goto error;
	}

	/* make the final decision on the type we want */
	ret = -ENOMEDIUM;
	if (params->force && !(vlocation->vldb.vidmask & (1 << params->type)))
		goto error;

	srvtmask = 0;
	for (loop = 0; loop < vlocation->vldb.nservers; loop++)
		srvtmask |= vlocation->vldb.srvtmask[loop];

	if (params->force) {
		if (!(srvtmask & (1 << params->type)))
			goto error;
	} else if (srvtmask & AFS_VOL_VTM_RO) {
		params->type = AFSVL_ROVOL;
	} else if (srvtmask & AFS_VOL_VTM_RW) {
		params->type = AFSVL_RWVOL;
	} else {
		goto error;
	}

	down_write(&params->cell->vl_sem);

	/* is the volume already active? */
	if (vlocation->vols[params->type]) {
		/* yes - re-use it */
		volume = vlocation->vols[params->type];
		afs_get_volume(volume);
		goto success;
	}

	/* create a new volume record */
	_debug("creating new volume record");

	ret = -ENOMEM;
	volume = kzalloc(sizeof(struct afs_volume), GFP_KERNEL);
	if (!volume)
		goto error_up;

	atomic_set(&volume->usage, 1);
	volume->type		= params->type;
	volume->type_force	= params->force;
	volume->cell		= params->cell;
	volume->vid		= vlocation->vldb.vid[params->type];

	ret = bdi_setup_and_register(&volume->bdi, "afs", BDI_CAP_MAP_COPY);
	if (ret)
		goto error_bdi;

	init_rwsem(&volume->server_sem);

	/* look up all the applicable server records */
	for (loop = 0; loop < 8; loop++) {
		if (vlocation->vldb.srvtmask[loop] & (1 << volume->type)) {
			server = afs_lookup_server(
			       volume->cell, &vlocation->vldb.servers[loop]);
			if (IS_ERR(server)) {
				ret = PTR_ERR(server);
				goto error_discard;
			}

			volume->servers[volume->nservers] = server;
			volume->nservers++;
		}
	}

	/* attach the cache and volume location */
#ifdef CONFIG_AFS_FSCACHE
	volume->cache = fscache_acquire_cookie(vlocation->cache,
					       &afs_volume_cache_index_def,
					       volume, true);
#endif
	afs_get_vlocation(vlocation);
	volume->vlocation = vlocation;

	vlocation->vols[volume->type] = volume;

success:
	_debug("kAFS selected %s volume %08x",
	       afs_voltypes[volume->type], volume->vid);
	up_write(&params->cell->vl_sem);
	afs_put_vlocation(vlocation);
	_leave(" = %p", volume);
	return volume;

	/* clean up */
error_up:
	up_write(&params->cell->vl_sem);
error:
	afs_put_vlocation(vlocation);
	_leave(" = %d", ret);
	return ERR_PTR(ret);

error_discard:
	bdi_destroy(&volume->bdi);
error_bdi:
	up_write(&params->cell->vl_sem);

	for (loop = volume->nservers - 1; loop >= 0; loop--)
		afs_put_server(volume->servers[loop]);

	kfree(volume);
	goto error;
}
Пример #20
0
/*
 * fetch file status from the volume
 * - don't issue a fetch if:
 *   - the changed bit is not set and there's a valid callback
 *   - there are any outstanding ops that will fetch the status
 * - TODO implement local caching
 */
int afs_vnode_fetch_status(struct afs_vnode *vnode,
			   struct afs_vnode *auth_vnode, struct key *key)
{
	struct afs_server *server;
	unsigned long acl_order;
	int ret;

	DECLARE_WAITQUEUE(myself, current);

	_enter("%s,{%x:%u.%u}",
	       vnode->volume->vlocation->vldb.name,
	       vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);

	if (!test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&
	    vnode->cb_promised) {
		_leave(" [unchanged]");
		return 0;
	}

	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
		_leave(" [deleted]");
		return -ENOENT;
	}

	acl_order = 0;
	if (auth_vnode)
		acl_order = auth_vnode->acl_order;

	spin_lock(&vnode->lock);

	if (!test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&
	    vnode->cb_promised) {
		spin_unlock(&vnode->lock);
		_leave(" [unchanged]");
		return 0;
	}

	ASSERTCMP(vnode->update_cnt, >=, 0);

	if (vnode->update_cnt > 0) {
		/* someone else started a fetch */
		_debug("wait on fetch %d", vnode->update_cnt);

		set_current_state(TASK_UNINTERRUPTIBLE);
		ASSERT(myself.func != NULL);
		add_wait_queue(&vnode->update_waitq, &myself);

		/* wait for the status to be updated */
		for (;;) {
			if (!test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags))
				break;
			if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
				break;

			/* check to see if it got updated and invalidated all
			 * before we saw it */
			if (vnode->update_cnt == 0) {
				remove_wait_queue(&vnode->update_waitq,
						  &myself);
				set_current_state(TASK_RUNNING);
				goto get_anyway;
			}

			spin_unlock(&vnode->lock);

			schedule();
			set_current_state(TASK_UNINTERRUPTIBLE);

			spin_lock(&vnode->lock);
		}

		remove_wait_queue(&vnode->update_waitq, &myself);
		spin_unlock(&vnode->lock);
		set_current_state(TASK_RUNNING);

		return test_bit(AFS_VNODE_DELETED, &vnode->flags) ?
			-ENOENT : 0;
	}

get_anyway:
	/* okay... we're going to have to initiate the op */
	vnode->update_cnt++;

	spin_unlock(&vnode->lock);

	/* merge AFS status fetches and clear outstanding callback on this
	 * vnode */
	do {
		/* pick a server to query */
		server = afs_volume_pick_fileserver(vnode);
		if (IS_ERR(server))
			goto no_server;

		_debug("USING SERVER: %p{%08x}",
		       server, ntohl(server->addr.s_addr));

		ret = afs_fs_fetch_file_status(server, key, vnode, NULL,
					       &afs_sync_call);

	} while (!afs_volume_release_fileserver(vnode, server, ret));

	/* adjust the flags */
	if (ret == 0) {
		_debug("adjust");
		if (auth_vnode)
			afs_cache_permit(vnode, key, acl_order);
		afs_vnode_finalise_status_update(vnode, server);
		afs_put_server(server);
	} else {
		_debug("failed [%d]", ret);
		afs_vnode_status_update_failed(vnode, ret);
	}

	ASSERTCMP(vnode->update_cnt, >=, 0);

	_leave(" = %d [cnt %d]", ret, vnode->update_cnt);
	return ret;

no_server:
	spin_lock(&vnode->lock);
	vnode->update_cnt--;
	ASSERTCMP(vnode->update_cnt, >=, 0);
	spin_unlock(&vnode->lock);
	_leave(" = %ld [cnt %d]", PTR_ERR(server), vnode->update_cnt);
	return PTR_ERR(server);
}
Пример #21
0
/*
 * rename a file
 */
int afs_vnode_rename(struct afs_vnode *orig_dvnode,
		     struct afs_vnode *new_dvnode,
		     struct key *key,
		     const char *orig_name,
		     const char *new_name)
{
	struct afs_server *server;
	int ret;

	_enter("%s{%x:%u.%u},%s{%u,%u,%u},%x,%s,%s",
	       orig_dvnode->volume->vlocation->vldb.name,
	       orig_dvnode->fid.vid,
	       orig_dvnode->fid.vnode,
	       orig_dvnode->fid.unique,
	       new_dvnode->volume->vlocation->vldb.name,
	       new_dvnode->fid.vid,
	       new_dvnode->fid.vnode,
	       new_dvnode->fid.unique,
	       key_serial(key),
	       orig_name,
	       new_name);

	/* this op will fetch the status on both the directories we're dealing
	 * with */
	spin_lock(&orig_dvnode->lock);
	orig_dvnode->update_cnt++;
	spin_unlock(&orig_dvnode->lock);
	if (new_dvnode != orig_dvnode) {
		spin_lock(&new_dvnode->lock);
		new_dvnode->update_cnt++;
		spin_unlock(&new_dvnode->lock);
	}

	do {
		/* pick a server to query */
		server = afs_volume_pick_fileserver(orig_dvnode);
		if (IS_ERR(server))
			goto no_server;

		_debug("USING SERVER: %08x\n", ntohl(server->addr.s_addr));

		ret = afs_fs_rename(server, key, orig_dvnode, orig_name,
				    new_dvnode, new_name, &afs_sync_call);

	} while (!afs_volume_release_fileserver(orig_dvnode, server, ret));

	/* adjust the flags */
	if (ret == 0) {
		afs_vnode_finalise_status_update(orig_dvnode, server);
		if (new_dvnode != orig_dvnode)
			afs_vnode_finalise_status_update(new_dvnode, server);
		afs_put_server(server);
	} else {
		afs_vnode_status_update_failed(orig_dvnode, ret);
		if (new_dvnode != orig_dvnode)
			afs_vnode_status_update_failed(new_dvnode, ret);
	}

	_leave(" = %d [cnt %d]", ret, orig_dvnode->update_cnt);
	return ret;

no_server:
	spin_lock(&orig_dvnode->lock);
	orig_dvnode->update_cnt--;
	ASSERTCMP(orig_dvnode->update_cnt, >=, 0);
	spin_unlock(&orig_dvnode->lock);
	if (new_dvnode != orig_dvnode) {
		spin_lock(&new_dvnode->lock);
		new_dvnode->update_cnt--;
		ASSERTCMP(new_dvnode->update_cnt, >=, 0);
		spin_unlock(&new_dvnode->lock);
	}