blob: 0fa8216fd0eb09d48dd0f4b9d8165a9954beef9d [file] [log] [blame]
/*
*
* Intel Management Engine Interface (Intel MEI) Linux driver
* Copyright (c) 2003-2011, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will 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.
*
*/
#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include "mei_dev.h"
#include "hw.h"
#include "interface.h"
#include "mei.h"
const uuid_le mei_amthi_guid = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d, 0xac,
0xa8, 0x46, 0xe0, 0xff, 0x65,
0x81, 0x4c);
/**
* mei_io_list_init - Sets up a queue list.
*
* @list: An instance io list structure
* @dev: the device structure
*/
void mei_io_list_init(struct mei_io_list *list)
{
/* initialize our queue list */
INIT_LIST_HEAD(&list->mei_cb.cb_list);
list->status = 0;
}
/**
* mei_io_list_flush - removes list entry belonging to cl.
*
* @list: An instance of our list structure
* @cl: private data of the file object
*/
void mei_io_list_flush(struct mei_io_list *list, struct mei_cl *cl)
{
struct mei_cl_cb *cb_pos = NULL;
struct mei_cl_cb *cb_next = NULL;
if (list->status != 0)
return;
if (list_empty(&list->mei_cb.cb_list))
return;
list_for_each_entry_safe(cb_pos, cb_next,
&list->mei_cb.cb_list, cb_list) {
if (cb_pos) {
struct mei_cl *cl_tmp;
cl_tmp = (struct mei_cl *)cb_pos->file_private;
if (mei_cl_cmp_id(cl, cl_tmp))
list_del(&cb_pos->cb_list);
}
}
}
/**
* mei_cl_flush_queues - flushes queue lists belonging to cl.
*
* @dev: the device structure
* @cl: private data of the file object
*/
int mei_cl_flush_queues(struct mei_cl *cl)
{
if (!cl || !cl->dev)
return -EINVAL;
dev_dbg(&cl->dev->pdev->dev, "remove list entry belonging to cl\n");
mei_io_list_flush(&cl->dev->read_list, cl);
mei_io_list_flush(&cl->dev->write_list, cl);
mei_io_list_flush(&cl->dev->write_waiting_list, cl);
mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
mei_io_list_flush(&cl->dev->amthi_cmd_list, cl);
mei_io_list_flush(&cl->dev->amthi_read_complete_list, cl);
return 0;
}
/**
* mei_reset_iamthif_params - initializes mei device iamthif
*
* @dev: the device structure
*/
static void mei_reset_iamthif_params(struct mei_device *dev)
{
/* reset iamthif parameters. */
dev->iamthif_current_cb = NULL;
dev->iamthif_msg_buf_size = 0;
dev->iamthif_msg_buf_index = 0;
dev->iamthif_canceled = false;
dev->iamthif_ioctl = false;
dev->iamthif_state = MEI_IAMTHIF_IDLE;
dev->iamthif_timer = 0;
}
/**
* init_mei_device - allocates and initializes the mei device structure
*
* @pdev: The pci device structure
*
* returns The mei_device_device pointer on success, NULL on failure.
*/
struct mei_device *mei_device_init(struct pci_dev *pdev)
{
struct mei_device *dev;
dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
if (!dev)
return NULL;
/* setup our list array */
INIT_LIST_HEAD(&dev->file_list);
INIT_LIST_HEAD(&dev->wd_cl.link);
INIT_LIST_HEAD(&dev->iamthif_cl.link);
mutex_init(&dev->device_lock);
init_waitqueue_head(&dev->wait_recvd_msg);
init_waitqueue_head(&dev->wait_stop_wd);
dev->mei_state = MEI_INITIALIZING;
dev->iamthif_state = MEI_IAMTHIF_IDLE;
mei_io_list_init(&dev->read_list);
mei_io_list_init(&dev->write_list);
mei_io_list_init(&dev->write_waiting_list);
mei_io_list_init(&dev->ctrl_wr_list);
mei_io_list_init(&dev->ctrl_rd_list);
mei_io_list_init(&dev->amthi_cmd_list);
mei_io_list_init(&dev->amthi_read_complete_list);
dev->pdev = pdev;
return dev;
}
/**
* mei_hw_init - initializes host and fw to start work.
*
* @dev: the device structure
*
* returns 0 on success, <0 on failure.
*/
int mei_hw_init(struct mei_device *dev)
{
int err = 0;
int ret;
mutex_lock(&dev->device_lock);
dev->host_hw_state = mei_hcsr_read(dev);
dev->me_hw_state = mei_mecsr_read(dev);
dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
/* acknowledge interrupt and stop interupts */
if ((dev->host_hw_state & H_IS) == H_IS)
mei_reg_write(dev, H_CSR, dev->host_hw_state);
dev->recvd_msg = false;
dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
mei_reset(dev, 1);
dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
/* wait for ME to turn on ME_RDY */
if (!dev->recvd_msg) {
mutex_unlock(&dev->device_lock);
err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
dev->recvd_msg, MEI_INTEROP_TIMEOUT);
mutex_lock(&dev->device_lock);
}
if (err <= 0 && !dev->recvd_msg) {
dev->mei_state = MEI_DISABLED;
dev_dbg(&dev->pdev->dev,
"wait_event_interruptible_timeout failed"
"on wait for ME to turn on ME_RDY.\n");
ret = -ENODEV;
goto out;
}
if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
dev->mei_state = MEI_DISABLED;
dev_dbg(&dev->pdev->dev,
"host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
if (!(dev->host_hw_state & H_RDY))
dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
if (!(dev->me_hw_state & ME_RDY_HRA))
dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
printk(KERN_ERR "mei: link layer initialization failed.\n");
ret = -ENODEV;
goto out;
}
if (dev->version.major_version != HBM_MAJOR_VERSION ||
dev->version.minor_version != HBM_MINOR_VERSION) {
dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
ret = -ENODEV;
goto out;
}
dev->recvd_msg = false;
dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
dev_dbg(&dev->pdev->dev, "MEI start success.\n");
ret = 0;
out:
mutex_unlock(&dev->device_lock);
return ret;
}
/**
* mei_hw_reset - resets fw via mei csr register.
*
* @dev: the device structure
* @interrupts_enabled: if interrupt should be enabled after reset.
*/
static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
{
dev->host_hw_state |= (H_RST | H_IG);
if (interrupts_enabled)
mei_enable_interrupts(dev);
else
mei_disable_interrupts(dev);
}
/**
* mei_reset - resets host and fw.
*
* @dev: the device structure
* @interrupts_enabled: if interrupt should be enabled after reset.
*/
void mei_reset(struct mei_device *dev, int interrupts_enabled)
{
struct mei_cl *cl_pos = NULL;
struct mei_cl *cl_next = NULL;
struct mei_cl_cb *cb_pos = NULL;
struct mei_cl_cb *cb_next = NULL;
bool unexpected;
if (dev->mei_state == MEI_RECOVERING_FROM_RESET) {
dev->need_reset = true;
return;
}
unexpected = (dev->mei_state != MEI_INITIALIZING &&
dev->mei_state != MEI_DISABLED &&
dev->mei_state != MEI_POWER_DOWN &&
dev->mei_state != MEI_POWER_UP);
dev->host_hw_state = mei_hcsr_read(dev);
dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
dev->host_hw_state);
mei_hw_reset(dev, interrupts_enabled);
dev->host_hw_state &= ~H_RST;
dev->host_hw_state |= H_IG;
mei_hcsr_set(dev);
dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
dev->host_hw_state);
dev->need_reset = false;
if (dev->mei_state != MEI_INITIALIZING) {
if (dev->mei_state != MEI_DISABLED &&
dev->mei_state != MEI_POWER_DOWN)
dev->mei_state = MEI_RESETING;
list_for_each_entry_safe(cl_pos,
cl_next, &dev->file_list, link) {
cl_pos->state = MEI_FILE_DISCONNECTED;
cl_pos->mei_flow_ctrl_creds = 0;
cl_pos->read_cb = NULL;
cl_pos->timer_count = 0;
}
/* remove entry if already in list */
dev_dbg(&dev->pdev->dev, "list del iamthif and wd file list.\n");
mei_remove_client_from_file_list(dev,
dev->wd_cl.host_client_id);
mei_remove_client_from_file_list(dev,
dev->iamthif_cl.host_client_id);
mei_reset_iamthif_params(dev);
dev->wd_due_counter = 0;
dev->extra_write_index = 0;
}
dev->me_clients_num = 0;
dev->rd_msg_hdr = 0;
dev->stop = false;
dev->wd_pending = false;
/* update the state of the registers after reset */
dev->host_hw_state = mei_hcsr_read(dev);
dev->me_hw_state = mei_mecsr_read(dev);
dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
dev->host_hw_state, dev->me_hw_state);
if (unexpected)
dev_warn(&dev->pdev->dev, "unexpected reset.\n");
/* Wake up all readings so they can be interrupted */
list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
if (waitqueue_active(&cl_pos->rx_wait)) {
dev_dbg(&dev->pdev->dev, "Waking up client!\n");
wake_up_interruptible(&cl_pos->rx_wait);
}
}
/* remove all waiting requests */
if (dev->write_list.status == 0 &&
!list_empty(&dev->write_list.mei_cb.cb_list)) {
list_for_each_entry_safe(cb_pos, cb_next,
&dev->write_list.mei_cb.cb_list, cb_list) {
if (cb_pos) {
list_del(&cb_pos->cb_list);
mei_free_cb_private(cb_pos);
cb_pos = NULL;
}
}
}
}
/**
* host_start_message - mei host sends start message.
*
* @dev: the device structure
*
* returns none.
*/
void mei_host_start_message(struct mei_device *dev)
{
struct mei_msg_hdr *mei_hdr;
struct hbm_host_version_request *host_start_req;
/* host start message */
mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
mei_hdr->host_addr = 0;
mei_hdr->me_addr = 0;
mei_hdr->length = sizeof(struct hbm_host_version_request);
mei_hdr->msg_complete = 1;
mei_hdr->reserved = 0;
host_start_req =
(struct hbm_host_version_request *) &dev->wr_msg_buf[1];
memset(host_start_req, 0, sizeof(struct hbm_host_version_request));
host_start_req->cmd.cmd = HOST_START_REQ_CMD;
host_start_req->host_version.major_version = HBM_MAJOR_VERSION;
host_start_req->host_version.minor_version = HBM_MINOR_VERSION;
dev->recvd_msg = false;
if (!mei_write_message(dev, mei_hdr,
(unsigned char *) (host_start_req),
mei_hdr->length)) {
dev_dbg(&dev->pdev->dev, "write send version message to FW fail.\n");
dev->mei_state = MEI_RESETING;
mei_reset(dev, 1);
}
dev->init_clients_state = MEI_START_MESSAGE;
dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
return ;
}
/**
* host_enum_clients_message - host sends enumeration client request message.
*
* @dev: the device structure
*
* returns none.
*/
void mei_host_enum_clients_message(struct mei_device *dev)
{
struct mei_msg_hdr *mei_hdr;
struct hbm_host_enum_request *host_enum_req;
mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
/* enumerate clients */
mei_hdr->host_addr = 0;
mei_hdr->me_addr = 0;
mei_hdr->length = sizeof(struct hbm_host_enum_request);
mei_hdr->msg_complete = 1;
mei_hdr->reserved = 0;
host_enum_req = (struct hbm_host_enum_request *) &dev->wr_msg_buf[1];
memset(host_enum_req, 0, sizeof(struct hbm_host_enum_request));
host_enum_req->cmd.cmd = HOST_ENUM_REQ_CMD;
if (!mei_write_message(dev, mei_hdr,
(unsigned char *) (host_enum_req),
mei_hdr->length)) {
dev->mei_state = MEI_RESETING;
dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
mei_reset(dev, 1);
}
dev->init_clients_state = MEI_ENUM_CLIENTS_MESSAGE;
dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
return ;
}
/**
* allocate_me_clients_storage - allocates storage for me clients
*
* @dev: the device structure
*
* returns none.
*/
void mei_allocate_me_clients_storage(struct mei_device *dev)
{
struct mei_me_client *clients;
int b;
/* count how many ME clients we have */
for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
dev->me_clients_num++;
if (dev->me_clients_num <= 0)
return ;
if (dev->me_clients != NULL) {
kfree(dev->me_clients);
dev->me_clients = NULL;
}
dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
dev->me_clients_num * sizeof(struct mei_me_client));
/* allocate storage for ME clients representation */
clients = kcalloc(dev->me_clients_num,
sizeof(struct mei_me_client), GFP_KERNEL);
if (!clients) {
dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
dev->mei_state = MEI_RESETING;
mei_reset(dev, 1);
return ;
}
dev->me_clients = clients;
return ;
}
/**
* host_client_properties - reads properties for client
*
* @dev: the device structure
*
* returns none.
*/
void mei_host_client_properties(struct mei_device *dev)
{
struct mei_msg_hdr *mei_header;
struct hbm_props_request *host_cli_req;
int b;
u8 client_num = dev->me_client_presentation_num;
b = dev->me_client_index;
b = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, b);
if (b < MEI_CLIENTS_MAX) {
dev->me_clients[client_num].client_id = b;
dev->me_clients[client_num].mei_flow_ctrl_creds = 0;
mei_header = (struct mei_msg_hdr *)&dev->wr_msg_buf[0];
mei_header->host_addr = 0;
mei_header->me_addr = 0;
mei_header->length = sizeof(struct hbm_props_request);
mei_header->msg_complete = 1;
mei_header->reserved = 0;
host_cli_req = (struct hbm_props_request *)&dev->wr_msg_buf[1];
memset(host_cli_req, 0, sizeof(struct hbm_props_request));
host_cli_req->cmd.cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
host_cli_req->address = b;
if (!mei_write_message(dev, mei_header,
(unsigned char *)host_cli_req,
mei_header->length)) {
dev->mei_state = MEI_RESETING;
dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
mei_reset(dev, 1);
return;
}
dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
dev->me_client_index = b;
return;
}
/*
* Clear Map for indicating now ME clients
* with associated host client
*/
bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
dev->open_handle_count = 0;
bitmap_set(dev->host_clients_map, 0, 3);
dev->mei_state = MEI_ENABLED;
mei_wd_host_init(dev);
return;
}
/**
* mei_init_file_private - initializes private file structure.
*
* @priv: private file structure to be initialized
* @file: the file structure
*/
void mei_cl_init(struct mei_cl *priv, struct mei_device *dev)
{
memset(priv, 0, sizeof(struct mei_cl));
init_waitqueue_head(&priv->wait);
init_waitqueue_head(&priv->rx_wait);
init_waitqueue_head(&priv->tx_wait);
INIT_LIST_HEAD(&priv->link);
priv->reading_state = MEI_IDLE;
priv->writing_state = MEI_IDLE;
priv->dev = dev;
}
int mei_find_me_client_index(const struct mei_device *dev, uuid_le cuuid)
{
int i, res = -1;
for (i = 0; i < dev->me_clients_num; ++i)
if (uuid_le_cmp(cuuid,
dev->me_clients[i].props.protocol_name) == 0) {
res = i;
break;
}
return res;
}
/**
* mei_find_me_client_update_filext - searches for ME client guid
* sets client_id in mei_file_private if found
* @dev: the device structure
* @priv: private file structure to set client_id in
* @cguid: searched guid of ME client
* @client_id: id of host client to be set in file private structure
*
* returns ME client index
*/
u8 mei_find_me_client_update_filext(struct mei_device *dev, struct mei_cl *priv,
const uuid_le *cguid, u8 client_id)
{
int i;
if (!dev || !priv || !cguid)
return 0;
/* check for valid client id */
i = mei_find_me_client_index(dev, *cguid);
if (i >= 0) {
priv->me_client_id = dev->me_clients[i].client_id;
priv->state = MEI_FILE_CONNECTING;
priv->host_client_id = client_id;
list_add_tail(&priv->link, &dev->file_list);
return (u8)i;
}
return 0;
}
/**
* host_init_iamthif - mei initialization iamthif client.
*
* @dev: the device structure
*
*/
void mei_host_init_iamthif(struct mei_device *dev)
{
u8 i;
unsigned char *msg_buf;
mei_cl_init(&dev->iamthif_cl, dev);
dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
/* find ME amthi client */
i = mei_find_me_client_update_filext(dev, &dev->iamthif_cl,
&mei_amthi_guid, MEI_IAMTHIF_HOST_CLIENT_ID);
if (dev->iamthif_cl.state != MEI_FILE_CONNECTING) {
dev_dbg(&dev->pdev->dev, "failed to find iamthif client.\n");
return;
}
/* Do not render the system unusable when iamthif_mtu is not equal to
the value received from ME.
Assign iamthif_mtu to the value received from ME in order to solve the
hardware macro incompatibility. */
dev_dbg(&dev->pdev->dev, "[DEFAULT] IAMTHIF = %d\n", dev->iamthif_mtu);
dev->iamthif_mtu = dev->me_clients[i].props.max_msg_length;
dev_dbg(&dev->pdev->dev,
"IAMTHIF = %d\n",
dev->me_clients[i].props.max_msg_length);
kfree(dev->iamthif_msg_buf);
dev->iamthif_msg_buf = NULL;
/* allocate storage for ME message buffer */
msg_buf = kcalloc(dev->iamthif_mtu,
sizeof(unsigned char), GFP_KERNEL);
if (!msg_buf) {
dev_dbg(&dev->pdev->dev, "memory allocation for ME message buffer failed.\n");
return;
}
dev->iamthif_msg_buf = msg_buf;
if (!mei_connect(dev, &dev->iamthif_cl)) {
dev_dbg(&dev->pdev->dev, "Failed to connect to AMTHI client\n");
dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
dev->iamthif_cl.host_client_id = 0;
} else {
dev->iamthif_cl.timer_count = CONNECT_TIMEOUT;
}
}
/**
* mei_alloc_file_private - allocates a private file structure and sets it up.
* @file: the file structure
*
* returns The allocated file or NULL on failure
*/
struct mei_cl *mei_cl_allocate(struct mei_device *dev)
{
struct mei_cl *cl;
cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
if (!cl)
return NULL;
mei_cl_init(cl, dev);
return cl;
}
/**
* mei_disconnect_host_client - sends disconnect message to fw from host client.
*
* @dev: the device structure
* @cl: private data of the file object
*
* Locking: called under "dev->device_lock" lock
*
* returns 0 on success, <0 on failure.
*/
int mei_disconnect_host_client(struct mei_device *dev, struct mei_cl *cl)
{
int rets, err;
long timeout = 15; /* 15 seconds */
struct mei_cl_cb *cb;
if (!dev || !cl)
return -ENODEV;
if (cl->state != MEI_FILE_DISCONNECTING)
return 0;
cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
if (!cb)
return -ENOMEM;
INIT_LIST_HEAD(&cb->cb_list);
cb->file_private = cl;
cb->major_file_operations = MEI_CLOSE;
if (dev->mei_host_buffer_is_empty) {
dev->mei_host_buffer_is_empty = false;
if (mei_disconnect(dev, cl)) {
mdelay(10); /* Wait for hardware disconnection ready */
list_add_tail(&cb->cb_list,
&dev->ctrl_rd_list.mei_cb.cb_list);
} else {
rets = -ENODEV;
dev_dbg(&dev->pdev->dev, "failed to call mei_disconnect.\n");
goto free;
}
} else {
dev_dbg(&dev->pdev->dev, "add disconnect cb to control write list\n");
list_add_tail(&cb->cb_list,
&dev->ctrl_wr_list.mei_cb.cb_list);
}
mutex_unlock(&dev->device_lock);
err = wait_event_timeout(dev->wait_recvd_msg,
(MEI_FILE_DISCONNECTED == cl->state),
timeout * HZ);
mutex_lock(&dev->device_lock);
if (MEI_FILE_DISCONNECTED == cl->state) {
rets = 0;
dev_dbg(&dev->pdev->dev, "successfully disconnected from FW client.\n");
} else {
rets = -ENODEV;
if (MEI_FILE_DISCONNECTED != cl->state)
dev_dbg(&dev->pdev->dev, "wrong status client disconnect.\n");
if (err)
dev_dbg(&dev->pdev->dev,
"wait failed disconnect err=%08x\n",
err);
dev_dbg(&dev->pdev->dev, "failed to disconnect from FW client.\n");
}
mei_io_list_flush(&dev->ctrl_rd_list, cl);
mei_io_list_flush(&dev->ctrl_wr_list, cl);
free:
mei_free_cb_private(cb);
return rets;
}
/**
* mei_remove_client_from_file_list -
* removes file private data from device file list
*
* @dev: the device structure
* @host_client_id: host client id to be removed
*/
void mei_remove_client_from_file_list(struct mei_device *dev,
u8 host_client_id)
{
struct mei_cl *cl_pos = NULL;
struct mei_cl *cl_next = NULL;
list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
if (host_client_id == cl_pos->host_client_id) {
dev_dbg(&dev->pdev->dev, "remove host client = %d, ME client = %d\n",
cl_pos->host_client_id,
cl_pos->me_client_id);
list_del_init(&cl_pos->link);
break;
}
}
}