mars/mars_client.c

605 lines
16 KiB
C

// (c) 2010 Thomas Schoebel-Theuer / 1&1 Internet AG
// Client brick (just for demonstration)
//#define BRICK_DEBUGGING
//#define MARS_DEBUGGING
//#define IO_DEBUGGING
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/kthread.h>
#include "mars.h"
///////////////////////// own type definitions ////////////////////////
#include "mars_client.h"
///////////////////////// own helper functions ////////////////////////
static int thread_count = 0;
static void _kill_socket(struct client_output *output)
{
if (output->socket) {
MARS_DBG("shutdown socket\n");
kernel_sock_shutdown(output->socket, SHUT_WR);
//sock_release(output->socket);
output->socket = NULL;
}
}
static void _kill_thread(struct client_threadinfo *ti)
{
if (ti->thread) {
kthread_stop(ti->thread);
}
}
static int _request_info(struct client_output *output)
{
struct mars_cmd cmd = {
.cmd_code = CMD_GETINFO,
};
int status;
MARS_DBG("\n");
status = mars_send_struct(&output->socket, &cmd, mars_cmd_meta);
if (unlikely(status < 0)) {
MARS_DBG("send of getinfo failed, status = %d\n", status);
}
return status;
}
static int _connect(struct client_output *output, const char *str)
{
struct sockaddr_storage sockaddr = {};
int status;
if (!output->path) {
output->path = kstrdup(str, GFP_MARS);
status = -ENOMEM;
if (!output->path) {
MARS_DBG("no mem\n");
goto done;
}
status = -EINVAL;
output->host = strchr(output->path, '@');
if (!output->host) {
kfree(output->path);
output->path = NULL;
MARS_ERR("parameter string '%s' contains no remote specifier with '@'-syntax\n", str);
goto done;
}
*output->host++ = '\0';
}
status = mars_create_sockaddr(&sockaddr, output->host);
if (unlikely(status < 0)) {
MARS_DBG("no sockaddr, status = %d\n", status);
goto done;
}
status = mars_create_socket(&output->socket, &sockaddr, false);
if (unlikely(status < 0)) {
if (status == -EINPROGRESS) {
MARS_DBG("operation is in progress....\n");
goto really_done; // give it a chance next time
}
MARS_DBG("no socket, status = %d\n", status);
goto done;
}
{
struct mars_cmd cmd = {
.cmd_code = CMD_CONNECT,
.cmd_str1 = output->path,
};
status = mars_send_struct(&output->socket, &cmd, mars_cmd_meta);
if (unlikely(status < 0)) {
MARS_DBG("send of connect failed, status = %d\n", status);
goto done;
}
}
if (status >= 0) {
status = _request_info(output);
}
done:
if (status < 0) {
MARS_INF("cannot connect to remote host '%s' (status = %d) -- retrying\n", output->host ? output->host : "NULL", status);
_kill_socket(output);
}
really_done:
return status;
}
////////////////// own brick / input / output operations //////////////////
static int client_get_info(struct client_output *output, struct mars_info *info)
{
int status;
output->got_info = false;
output->get_info = true;
wake_up_interruptible(&output->event);
wait_event_interruptible_timeout(output->info_event, output->got_info, 60 * HZ);
status = -EIO;
if (output->got_info && info) {
memcpy(info, &output->info, sizeof(*info));
status = 0;
}
//done:
return status;
}
static int client_ref_get(struct client_output *output, struct mref_object *mref)
{
#if 1
/* Limit transfers to page boundaries.
* Currently, this is more restrictive than necessary.
* TODO: improve performance by doing better when possible.
* This needs help from the server in some efficient way.
*/
int maxlen = PAGE_SIZE - (mref->ref_pos & (PAGE_SIZE-1));
if (mref->ref_len > maxlen)
mref->ref_len = maxlen;
#endif
_CHECK_ATOMIC(&mref->ref_count, !=, 0);
if (!mref->ref_data) { // buffered IO
struct client_mref_aspect *mref_a = client_mref_get_aspect(output, mref);
if (!mref_a)
return -EILSEQ;
mref->ref_data = kmalloc(mref->ref_len, GFP_MARS);
if (!mref->ref_data)
return -ENOMEM;
mref_a->do_dealloc = true;
mref->ref_flags = 0;
}
atomic_inc(&mref->ref_count);
return 0;
}
static void client_ref_put(struct client_output *output, struct mref_object *mref)
{
struct client_mref_aspect *mref_a;
CHECK_ATOMIC(&mref->ref_count, 1);
if (!atomic_dec_and_test(&mref->ref_count))
return;
mref_a = client_mref_get_aspect(output, mref);
if (mref_a && mref_a->do_dealloc) {
kfree(mref->ref_data);
}
client_free_mref(mref);
}
static void client_ref_io(struct client_output *output, struct mref_object *mref)
{
struct generic_callback *cb;
struct client_mref_aspect *mref_a;
int hash_index;
unsigned long flags;
int error = -EINVAL;
mref_a = client_mref_get_aspect(output, mref);
if (unlikely(!mref_a)) {
goto error;
}
while (output->brick->max_flying > 0 && atomic_read(&output->fly_count) > output->brick->max_flying) {
MARS_IO("sleeping request pos = %lld len = %d rw = %d (flying = %d)\n", mref->ref_pos, mref->ref_len, mref->ref_rw, atomic_read(&output->fly_count));
#ifdef IO_DEBUGGING
msleep(3000);
#else
msleep(1000 * 2 / HZ);
#endif
}
atomic_inc(&output->fly_count);
atomic_inc(&mref->ref_count);
traced_lock(&output->lock, flags);
mref->ref_id = ++output->last_id;
list_add_tail(&mref_a->io_head, &output->mref_list);
traced_unlock(&output->lock, flags);
hash_index = mref->ref_id % CLIENT_HASH_MAX;
traced_lock(&output->hash_lock[hash_index], flags);
list_add_tail(&mref_a->hash_head, &output->hash_table[hash_index]);
traced_unlock(&output->hash_lock[hash_index], flags);
MARS_IO("added request id = %d pos = %lld len = %d rw = %d (flying = %d)\n", mref->ref_id, mref->ref_pos, mref->ref_len, mref->ref_rw, atomic_read(&output->fly_count));
wake_up_interruptible(&output->event);
return;
error:
MARS_ERR("IO error = %d\n", error);
cb = mref->ref_cb;
cb->cb_error = error;
cb->cb_fn(cb);
client_ref_put(output, mref);
}
static int receiver_thread(void *data)
{
struct client_output *output = data;
int status = 0;
while (!kthread_should_stop() && output->socket) {
struct mars_cmd cmd = {};
struct list_head *tmp;
struct client_mref_aspect *mref_a = NULL;
struct mref_object *mref = NULL;
struct generic_callback *cb;
unsigned long flags;
status = mars_recv_struct(&output->socket, &cmd, mars_cmd_meta);
MARS_IO("got cmd = %d status = %d\n", cmd.cmd_code, status);
if (status < 0)
goto done;
switch (cmd.cmd_code) {
case CMD_CONNECT:
if (cmd.cmd_int1 < 0) {
status = cmd.cmd_int1;
MARS_ERR("at remote side: brick connect failed, remote status = %d\n", status);
goto done;
}
break;
case CMD_CB:
{
int hash_index = mref->ref_id % CLIENT_HASH_MAX;
traced_lock(&output->hash_lock[hash_index], flags);
for (tmp = output->hash_table[hash_index].next; tmp != &output->hash_table[hash_index]; tmp = tmp->next) {
mref_a = container_of(tmp, struct client_mref_aspect, hash_head);
if (mref_a->object->ref_id == cmd.cmd_int1) {
list_del_init(&mref_a->hash_head);
mref = mref_a->object;
break;
}
}
traced_unlock(&output->hash_lock[hash_index], flags);
if (!mref) {
MARS_ERR("got unknown id = %d for callback\n", cmd.cmd_int1);
status = -EBADR;
goto done;
}
MARS_IO("got callback id = %d, old pos = %lld len = %d rw = %d\n", mref->ref_id, mref->ref_pos, mref->ref_len, mref->ref_rw);
status = mars_recv_cb(&output->socket, mref);
MARS_IO("new status = %d, pos = %lld len = %d rw = %d\n", status, mref->ref_pos, mref->ref_len, mref->ref_rw);
if (status < 0) {
MARS_ERR("interrupted data transfer during callback, status = %d\n", status);
traced_lock(&output->hash_lock[hash_index], flags);
list_add_tail(&mref_a->hash_head, &output->hash_table[hash_index]);
traced_unlock(&output->hash_lock[hash_index], flags);
goto done;
}
traced_lock(&output->lock, flags);
list_del_init(&mref_a->io_head);
traced_unlock(&output->lock, flags);
atomic_dec(&output->fly_count);
cb = mref->ref_cb;
cb->cb_fn(cb);
client_ref_put(output, mref);
break;
}
case CMD_GETINFO:
status = mars_recv_struct(&output->socket, &output->info, mars_info_meta);
if (status < 0) {
MARS_ERR("got bad info from remote side, status = %d\n", status);
goto done;
}
output->got_info = true;
wake_up_interruptible(&output->info_event);
break;
default:
MARS_ERR("got bad command %d from remote side, terminating.\n", cmd.cmd_code);
status = -EBADR;
goto done;
}
}
done:
if (status < 0) {
MARS_ERR("receiver thread terminated with status = %d\n", status);
}
#if 0
if (output->socket) {
MARS_INF("shutting down socket\n");
kernel_sock_shutdown(output->socket, SHUT_WR);
msleep(1000);
output->socket = NULL;
}
#endif
output->receiver.terminated = true;
wake_up_interruptible(&output->receiver.run_event);
return status;
}
static int sender_thread(void *data)
{
struct client_output *output = data;
struct client_brick *brick = output->brick;
int status = 0;
while (!kthread_should_stop()) {
struct list_head *tmp;
struct client_mref_aspect *mref_a;
struct mref_object *mref;
unsigned long flags;
bool do_resubmit = false;
if (unlikely(!output->socket)) {
status = _connect(output, brick->brick_name);
MARS_IO("connect status = %d\n", status);
if (unlikely(status < 0)) {
msleep(5000);
continue;
}
do_resubmit = true;
}
if (do_resubmit) {
/* Re-Submit any waiting requests
*/
MARS_IO("re-submit\n");
traced_lock(&output->lock, flags);
if (!list_empty(&output->wait_list)) {
struct list_head *first = output->wait_list.next;
struct list_head *last = output->wait_list.prev;
struct list_head *old_start = output->mref_list.next;
#define list_connect __list_del // the original routine has a misleading name: in reality it is more general
list_connect(&output->mref_list, first);
list_connect(last, old_start);
INIT_LIST_HEAD(&output->wait_list);
MARS_IO("done re-submit %p %p\n", first, last);
}
traced_unlock(&output->lock, flags);
}
wait_event_interruptible_timeout(output->event, !list_empty(&output->mref_list) || output->get_info, 1 * HZ);
if (unlikely(output->receiver.terminated)) {
output->receiver.terminated = false;
output->receiver.thread = kthread_create(receiver_thread, output, "mars_receiver%d", thread_count++);
if (unlikely(IS_ERR(output->receiver.thread))) {
MARS_ERR("cannot start receiver thread, status = %d\n", (int)PTR_ERR(output->receiver.thread));
output->receiver.thread = NULL;
output->receiver.terminated = true;
msleep(5000);
continue;
}
wake_up_process(output->receiver.thread);
}
if (output->get_info) {
status = _request_info(output);
if (status >= 0) {
output->get_info = false;
}
}
if (list_empty(&output->mref_list))
continue;
traced_lock(&output->lock, flags);
tmp = output->mref_list.next;
list_del(tmp);
list_add(tmp, &output->wait_list);
traced_unlock(&output->lock, flags);
mref_a = container_of(tmp, struct client_mref_aspect, io_head);
mref = mref_a->object;
MARS_IO("sending mref, id = %d pos = %lld len = %d rw = %d\n", mref->ref_id, mref->ref_pos, mref->ref_len, mref->ref_rw);
status = mars_send_mref(&output->socket, mref);
MARS_IO("status = %d\n", status);
if (unlikely(status < 0)) {
// retry submission on next occasion..
traced_lock(&output->lock, flags);
list_del(&mref_a->io_head);
list_add(&mref_a->io_head, &output->mref_list);
traced_unlock(&output->lock, flags);
MARS_ERR("sending failed, status = %d\n", status);
_kill_socket(output);
_kill_thread(&output->receiver);
wait_event_interruptible_timeout(output->receiver.run_event, output->receiver.terminated, 10 * HZ);
continue;
}
}
//done:
if (status < 0)
MARS_ERR("sender thread terminated with status = %d\n", status);
_kill_socket(output);
_kill_thread(&output->receiver);
output->sender.terminated = true;
wake_up_interruptible(&output->sender.run_event);
return status;
}
static int client_switch(struct client_brick *brick)
{
struct client_output *output = brick->outputs[0];
int status = 0;
if (brick->power.button) {
mars_power_led_off((void*)brick, false);
if (output->sender.terminated) {
output->sender.terminated = false;
output->sender.thread = kthread_create(sender_thread, output, "mars_sender%d", thread_count++);
if (unlikely(IS_ERR(output->sender.thread))) {
status = PTR_ERR(output->sender.thread);
MARS_ERR("cannot start sender thread, status = %d\n", status);
output->sender.thread = NULL;
output->sender.terminated = true;
goto done;
}
}
wake_up_process(output->sender.thread);
if (!output->sender.terminated) {
mars_power_led_on((void*)brick, true);
}
} else {
mars_power_led_on((void*)brick, false);
_kill_thread(&output->sender);
wait_event_interruptible_timeout(output->sender.run_event, output->sender.terminated, 10 * HZ);
if (output->sender.terminated) {
mars_power_led_off((void*)brick, !output->sender.thread);
}
}
done:
return status;
}
//////////////// object / aspect constructors / destructors ///////////////
static int client_mref_aspect_init_fn(struct generic_aspect *_ini, void *_init_data)
{
struct client_mref_aspect *ini = (void*)_ini;
INIT_LIST_HEAD(&ini->io_head);
INIT_LIST_HEAD(&ini->hash_head);
return 0;
}
static void client_mref_aspect_exit_fn(struct generic_aspect *_ini, void *_init_data)
{
struct client_mref_aspect *ini = (void*)_ini;
CHECK_HEAD_EMPTY(&ini->io_head);
CHECK_HEAD_EMPTY(&ini->hash_head);
}
MARS_MAKE_STATICS(client);
////////////////////// brick constructors / destructors ////////////////////
static int client_brick_construct(struct client_brick *brick)
{
return 0;
}
static int client_output_construct(struct client_output *output)
{
int i;
for (i = 0; i < CLIENT_HASH_MAX; i++) {
spin_lock_init(&output->hash_lock[i]);
INIT_LIST_HEAD(&output->hash_table[i]);
}
spin_lock_init(&output->lock);
INIT_LIST_HEAD(&output->mref_list);
INIT_LIST_HEAD(&output->wait_list);
init_waitqueue_head(&output->event);
init_waitqueue_head(&output->sender.run_event);
init_waitqueue_head(&output->receiver.run_event);
init_waitqueue_head(&output->info_event);
output->sender.terminated = true;
output->receiver.terminated = true;
return 0;
}
static int client_output_destruct(struct client_output *output)
{
if (output->path) {
kfree(output->path);
output->path = NULL;
}
return 0;
}
///////////////////////// static structs ////////////////////////
static struct client_brick_ops client_brick_ops = {
.brick_switch = client_switch,
};
static struct client_output_ops client_output_ops = {
.make_object_layout = client_make_object_layout,
.mars_get_info = client_get_info,
.mref_get = client_ref_get,
.mref_put = client_ref_put,
.mref_io = client_ref_io,
};
const struct client_input_type client_input_type = {
.type_name = "client_input",
.input_size = sizeof(struct client_input),
};
static const struct client_input_type *client_input_types[] = {
&client_input_type,
};
const struct client_output_type client_output_type = {
.type_name = "client_output",
.output_size = sizeof(struct client_output),
.master_ops = &client_output_ops,
.output_construct = &client_output_construct,
.output_destruct = &client_output_destruct,
.aspect_types = client_aspect_types,
.layout_code = {
[BRICK_OBJ_MREF] = LAYOUT_ALL,
}
};
static const struct client_output_type *client_output_types[] = {
&client_output_type,
};
const struct client_brick_type client_brick_type = {
.type_name = "client_brick",
.brick_size = sizeof(struct client_brick),
.max_inputs = 0,
.max_outputs = 1,
.master_ops = &client_brick_ops,
.default_input_types = client_input_types,
.default_output_types = client_output_types,
.brick_construct = &client_brick_construct,
};
EXPORT_SYMBOL_GPL(client_brick_type);
////////////////// module init stuff /////////////////////////
static int __init init_client(void)
{
MARS_INF("init_client()\n");
_client_brick_type = (void*)&client_brick_type;
return client_register_brick_type();
}
static void __exit exit_client(void)
{
MARS_INF("exit_client()\n");
client_unregister_brick_type();
}
MODULE_DESCRIPTION("MARS client brick");
MODULE_AUTHOR("Thomas Schoebel-Theuer <tst@1und1.de>");
MODULE_LICENSE("GPL");
module_init(init_client);
module_exit(exit_client);