RepoMirrors
/
mars
mirror of https://github.com/schoebel/mars
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
mars/mars_light.c

2376 lines
59 KiB
C
Raw Blame History

// (c) 2011 Thomas Schoebel-Theuer / 1&1 Internet AG
//#define BRICK_DEBUGGING
//#define MARS_DEBUGGING
//#define IO_DEBUGGING
//#define STAT_DEBUGGING // here means: display full statistics
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/debug_locks.h>
#include <linux/major.h>
#include <linux/genhd.h>
#include <linux/blkdev.h>
#define _STRATEGY
#include "mars.h"
#include <linux/kthread.h>
#include <linux/wait.h>
// used brick types
#include "mars_server.h"
#include "mars_client.h"
#include "mars_copy.h"
#include "mars_bio.h"
#include "mars_aio.h"
#include "mars_trans_logger.h"
#include "mars_if.h"
#if 0
#define inline __attribute__((__noinline__))
#endif
static struct task_struct *main_thread = NULL;
typedef int (*light_worker_fn)(void *buf, struct mars_dent *dent);
struct light_class {
char *cl_name;
int cl_len;
char cl_type;
bool cl_hostcontext;
bool cl_serial;
int cl_father;
light_worker_fn cl_forward;
light_worker_fn cl_backward;
};
///////////////////////////////////////////////////////////////////////
// TUNING
#define CONF_TRANS_CHUNKSIZE (128 * 1024)
//#define CONF_TRANS_ALIGN 512
#define CONF_TRANS_ALIGN 0
//#define FLUSH_DELAY (HZ / 100 + 1)
#define FLUSH_DELAY 0
//#define TRANS_FAKE
#define CONF_TRANS_BATCHLEN 32
//#define CONF_TRANS_FLYING 4
#define CONF_TRANS_FLYING 128
#define CONF_TRANS_PRIO MARS_PRIO_HIGH
//#define CONF_TRANS_LOG_READS false
#define CONF_TRANS_LOG_READS true
#define CONF_TRANS_MINIMIZE_LATENCY true
//#define CONF_ALL_BATCHLEN 2
#define CONF_ALL_BATCHLEN 1
//#define CONF_ALL_FLYING 4
#define CONF_ALL_FLYING 1
#define CONF_ALL_CONTENTION 0
#define CONF_ALL_PRESSURE 0
#define CONF_ALL_PRIO MARS_PRIO_LOW
#define CONF_ALL_MAX_QUEUE 10000
#define CONF_ALL_MAX_JIFFIES (180 * HZ)
#define IF_SKIP_SYNC true
#define IF_MAX_PLUGGED 10000
#define IF_READAHEAD 1
//#define IF_READAHEAD 0
#define BIO_READAHEAD 1
#define AIO_READAHEAD 1
#define AIO_WAIT_DURING_FDSYNC true
static
void _set_trans_params(struct mars_brick *_brick, void *private)
{
struct trans_logger_brick *trans_brick = (void*)_brick;
if (_brick->type != (void*)&trans_logger_brick_type) {
MARS_ERR("bad brick type\n");
return;
}
if (!trans_brick->q_phase2.q_ordering) {
trans_brick->q_phase1.q_batchlen = CONF_TRANS_BATCHLEN;
trans_brick->q_phase2.q_batchlen = CONF_ALL_BATCHLEN;
trans_brick->q_phase3.q_batchlen = CONF_ALL_BATCHLEN;
trans_brick->q_phase4.q_batchlen = CONF_ALL_BATCHLEN;
trans_brick->q_phase1.q_max_flying = CONF_TRANS_FLYING;
trans_brick->q_phase2.q_max_flying = CONF_ALL_FLYING;
trans_brick->q_phase3.q_max_flying = CONF_ALL_FLYING;
trans_brick->q_phase4.q_max_flying = CONF_ALL_FLYING;
trans_brick->q_phase1.q_max_contention = CONF_ALL_CONTENTION;
trans_brick->q_phase2.q_max_contention = CONF_ALL_CONTENTION;
trans_brick->q_phase3.q_max_contention = CONF_ALL_CONTENTION;
trans_brick->q_phase4.q_max_contention = CONF_ALL_CONTENTION;
trans_brick->q_phase1.q_over_pressure = CONF_ALL_PRESSURE;
trans_brick->q_phase2.q_over_pressure = CONF_ALL_PRESSURE;
trans_brick->q_phase3.q_over_pressure = CONF_ALL_PRESSURE;
trans_brick->q_phase4.q_over_pressure = CONF_ALL_PRESSURE;
trans_brick->q_phase1.q_io_prio = CONF_TRANS_PRIO;
trans_brick->q_phase2.q_io_prio = CONF_ALL_PRIO;
trans_brick->q_phase3.q_io_prio = CONF_ALL_PRIO;
trans_brick->q_phase4.q_io_prio = CONF_ALL_PRIO;
trans_brick->q_phase2.q_max_queued = CONF_ALL_MAX_QUEUE;
trans_brick->q_phase4.q_max_queued = CONF_ALL_MAX_QUEUE;
trans_brick->q_phase2.q_max_jiffies = CONF_ALL_MAX_JIFFIES;
trans_brick->q_phase4.q_max_jiffies = CONF_ALL_MAX_JIFFIES;
trans_brick->q_phase2.q_ordering = true;
trans_brick->q_phase4.q_ordering = true;
trans_brick->log_reads = CONF_TRANS_LOG_READS;
trans_brick->minimize_latency = CONF_TRANS_MINIMIZE_LATENCY;
#ifdef TRANS_FAKE
trans_brick->debug_shortcut = true;
#endif
trans_brick->align_size = CONF_TRANS_ALIGN;
trans_brick->chunk_size = CONF_TRANS_CHUNKSIZE;
trans_brick->flush_delay = FLUSH_DELAY;
if (!trans_brick->log_reads) {
trans_brick->q_phase2.q_max_queued = 0;
trans_brick->q_phase4.q_max_queued *= 2;
}
}
}
static
void _set_client_params(struct mars_brick *_brick, void *private)
{
// currently no params
}
static
void _set_aio_params(struct mars_brick *_brick, void *private)
{
struct aio_brick *aio_brick = (void*)_brick;
if (_brick->type == (void*)&client_brick_type) {
_set_client_params(_brick, private);
return;
}
if (_brick->type != (void*)&aio_brick_type) {
MARS_ERR("bad brick type\n");
return;
}
aio_brick->readahead = AIO_READAHEAD;
aio_brick->o_direct = false; // important!
aio_brick->o_fdsync = true;
aio_brick->wait_during_fdsync = AIO_WAIT_DURING_FDSYNC;
}
static
void _set_bio_params(struct mars_brick *_brick, void *private)
{
struct bio_brick *bio_brick;
if (_brick->type == (void*)&client_brick_type) {
_set_client_params(_brick, private);
return;
}
if (_brick->type == (void*)&aio_brick_type) {
_set_aio_params(_brick, private);
return;
}
if (_brick->type != (void*)&bio_brick_type) {
MARS_ERR("bad brick type\n");
return;
}
bio_brick = (void*)_brick;
bio_brick->ra_pages = BIO_READAHEAD;
}
static
void _set_if_params(struct mars_brick *_brick, void *private)
{
struct if_brick *if_brick = (void*)_brick;
if (_brick->type != (void*)&if_brick_type) {
MARS_ERR("bad brick type\n");
return;
}
if_brick->max_plugged = IF_MAX_PLUGGED;
if_brick->readahead = IF_READAHEAD;
if_brick->skip_sync = IF_SKIP_SYNC;
}
///////////////////////////////////////////////////////////////////////
// internal helpers
#define MARS_DELIM ','
static int _parse_args(struct mars_dent *dent, char *str, int count)
{
int i;
int status = -EINVAL;
if (!str)
goto done;
if (!dent->d_args) {
dent->d_args = kstrdup(str, GFP_MARS);
if (!dent->d_args) {
status = -ENOMEM;
goto done;
}
}
for (i = 0; i < count; i++) {
char *tmp;
int len;
if (!*str)
goto done;
if (i == count-1) {
len = strlen(str);
} else {
char *tmp = strchr(str, MARS_DELIM);
if (!tmp)
goto done;
len = (tmp - str);
}
tmp = kzalloc(len+1, GFP_MARS);
if (!tmp) {
status = -ENOMEM;
goto done;
}
if (dent->d_argv[i]) {
kfree(dent->d_argv[i]);
}
dent->d_argv[i] = tmp;
strncpy(dent->d_argv[i], str, len);
dent->d_argv[i][len] = '\0';
str += len;
if (i != count-1)
str++;
}
status = 0;
done:
if (status < 0) {
MARS_ERR("bad syntax '%s' (should have %d args), status = %d\n", dent->d_args ? dent->d_args : "", count, status);
}
return status;
}
///////////////////////////////////////////////////////////////////////
static
int __make_copy(
struct mars_global *global,
struct mars_dent *belongs,
const char *switch_path,
const char *copy_path,
const char *parent,
const char *argv[],
loff_t start_pos, // -1 means at EOF
struct copy_brick **__copy)
{
struct mars_brick *copy;
struct copy_brick *_copy;
const char *fullpath[2] = {};
struct mars_output *output[2] = {};
struct mars_info info[2] = {};
int i;
int status = -EINVAL;
if (!switch_path) {
goto done;
}
for (i = 0; i < 2; i++) {
struct mars_brick *aio;
if (parent) {
fullpath[i] = path_make("%s/%s", parent, argv[i]);
if (!fullpath[i]) {
MARS_ERR("cannot make path '%s/%s'\n", parent, argv[i]);
goto done;
}
} else {
fullpath[i] = argv[i];
}
aio =
make_brick_all(global,
NULL,
_set_bio_params,
NULL,
10 * HZ,
NULL,
(const struct generic_brick_type*)&bio_brick_type,
(const struct generic_brick_type*[]){},
NULL,
fullpath[i],
(const char *[]){},
0);
if (!aio) {
MARS_DBG("cannot instantiate '%s'\n", fullpath[i]);
goto done;
}
output[i] = aio->outputs[0];
}
copy =
make_brick_all(global,
belongs,
NULL,
NULL,
0,
fullpath[1],
(const struct generic_brick_type*)&copy_brick_type,
(const struct generic_brick_type*[]){NULL,NULL,NULL,NULL},
"%s",
"%s",
(const char *[]){"%s", "%s", "%s", "%s"},
4,
switch_path,
copy_path,
fullpath[0],
fullpath[0],
fullpath[1],
fullpath[1]);
if (!copy) {
MARS_DBG("fail '%s'\n", copy_path);
goto done;
}
copy->status_level = 2;
_copy = (void*)copy;
if (__copy)
*__copy = _copy;
/* Determine the copy area, switch on when necessary
*/
if (!_copy->power.button && _copy->power.led_off) {
_copy->copy_last = 0;
for (i = 0; i < 2; i++) {
status = output[i]->ops->mars_get_info(output[i], &info[i]);
if (status < 0) {
MARS_ERR("cannot determine current size of '%s'\n", argv[i]);
goto done;
}
MARS_DBG("%d '%s' current_size = %lld\n", i, fullpath[i], info[i].current_size);
}
_copy->copy_start = info[1].current_size;
if (start_pos != -1) {
_copy->copy_start = start_pos;
if (unlikely(info[0].current_size != info[1].current_size)) {
MARS_ERR("oops, devices have different size %lld != %lld at '%s'\n", info[0].current_size, info[1].current_size, copy_path);
status = -EINVAL;
goto done;
}
if (unlikely(start_pos > info[0].current_size)) {
MARS_ERR("bad start position %lld is larger than actual size %lld on '%s'\n", start_pos, info[0].current_size, copy_path);
status = -EINVAL;
goto done;
}
}
MARS_DBG("copy_start = %lld\n", _copy->copy_start);
_copy->copy_end = info[0].current_size;
MARS_DBG("copy_end = %lld\n", _copy->copy_end);
if (_copy->copy_start < _copy->copy_end) {
status = mars_power_button_recursive((void*)copy, true, false, 10 * HZ);
MARS_DBG("copy switch status = %d\n", status);
}
}
status = 0;
done:
MARS_DBG("status = %d\n", status);
for (i = 0; i < 2; i++) {
if (fullpath[i] && fullpath[i] != argv[i])
kfree(fullpath[i]);
}
return status;
}
///////////////////////////////////////////////////////////////////////
// remote workers
struct mars_peerinfo {
struct mars_global *global;
char *peer;
char *path;
struct socket *socket;
struct task_struct *thread;
spinlock_t lock;
struct list_head remote_dent_list;
//wait_queue_head_t event;
int maxdepth;
};
static
bool _is_usable_dir(const char *name)
{
if (!strncmp(name, "resource-", 9)
|| !strncmp(name, "switch", 6)
|| !strncmp(name, "actual", 6)
|| !strncmp(name, "defaults", 8)
) {
return true;
}
return false;
}
static
bool _is_peer_logfile(const char *name, const char *id)
{
int len = strlen(name);
int idlen = id ? strlen(id) : 4 + 9 + 1;
if (len <= idlen ||
strncmp(name, "log-", 4) != 0) {
MARS_DBG("not a logfile at all: '%s'\n", name);
return false;
}
if (id &&
name[len - idlen - 1] == '-' &&
strncmp(name + len - idlen, id, idlen) == 0) {
MARS_DBG("not a peer logfile: '%s'\n", name);
return false;
}
MARS_DBG("found peer logfile: '%s'\n", name);
return true;
}
static
int _update_file(struct mars_global *global, const char *switch_path, const char *copy_path, const char *file, const char *peer, loff_t end_pos)
{
const char *tmp = path_make("%s@%s", file, peer);
const char *argv[2] = { tmp, file };
struct copy_brick *copy = NULL;
int status = -ENOMEM;
if (unlikely(!tmp))
goto done;
MARS_DBG("src = '%s' dst = '%s'\n", tmp, file);
status = __make_copy(global, NULL, switch_path, copy_path, NULL, argv, -1, &copy);
if (status >= 0 && copy && !copy->permanent_update) {
if (end_pos > copy->copy_end) {
MARS_DBG("appending to '%s' %lld => %lld\n", copy_path, copy->copy_end, end_pos);
copy->copy_end = end_pos;
}
}
done:
if (tmp)
kfree(tmp);
return status;
}
static
int check_logfile(struct mars_peerinfo *peer, struct mars_dent *dent, struct mars_dent *parent, loff_t dst_size)
{
loff_t src_size = dent->new_stat.size;
const char *switch_path = NULL;
const char *copy_path = NULL;
const char *alias_path = NULL;
struct mars_dent *local_alias;
struct copy_brick *copy_brick;
int status = 0;
// plausibility checks
if (unlikely(dst_size > src_size)) {
MARS_WRN("my local copy is larger than the remote one, ignoring\n");
status = -EINVAL;
goto done;
}
// check whether (some/another) copy is already running
copy_path = path_make("%s/logfile-update", parent->d_path);
if (unlikely(!copy_path)) {
status = -ENOMEM;
goto done;
}
copy_brick = (struct copy_brick*)mars_find_brick(peer->global, &copy_brick_type, copy_path);
MARS_DBG("copy_path = '%s' copy_brick = %p dent = '%s'\n", copy_path, copy_brick, dent->d_path);
if (copy_brick) {
bool copy_is_done = (copy_brick->copy_last == copy_brick->copy_end);
bool is_my_copy = !strcmp(copy_brick->brick_name, dent->d_path);
bool is_next_copy = (dent->d_serial == parent->d_logfile_serial + 1);
MARS_DBG("copy brick '%s' copy_last = %lld copy_end = %lld dent '%s' serial = %d/%d is_done = %d is_my_copy = %d is_next_copy = %d\n", copy_brick->brick_name, copy_brick->copy_last, copy_brick->copy_end, dent->d_path, dent->d_serial, parent->d_logfile_serial, copy_is_done, is_my_copy, is_next_copy);
// ensure consecutiveness of logfiles
if (copy_is_done && !is_my_copy && is_next_copy) {
MARS_DBG("killing old copy brick '%s', now going to '%s'\n", copy_brick->brick_name, dent->d_path);
status = mars_kill_brick((void*)copy_brick);
if (status < 0)
goto done;
}
if (!is_my_copy) {
goto done;
}
}
status = 0;
if (dst_size >= src_size) { // nothing to do
goto done;
}
// check whether connection is allowed
switch_path = path_make("%s/switch-%s/connect", parent->d_path, my_id());
// start / treat copy brick instance
status = _update_file(peer->global, switch_path, copy_path, dent->d_path, peer->peer, src_size);
MARS_DBG("update '%s' from peer '%s' status = %d\n", dent->d_path, peer->peer, status);
if (status < 0) {
goto done;
}
parent->d_logfile_serial = dent->d_serial;
// create local alias symlink
alias_path = path_make("%s/log-%09d-%s", parent->d_path, dent->d_serial, my_id());
if (unlikely(!alias_path)) {
status = -ENOMEM;
goto done;
}
status = 0;
MARS_DBG("local alias for '%s' is '%s'\n", dent->d_path, alias_path);
local_alias = mars_find_dent((void*)peer->global, alias_path);
if (!local_alias) {
status = mars_symlink(dent->d_name, alias_path, &dent->new_stat.mtime, 0);
MARS_DBG("create alias '%s' -> '%s' status = %d\n", alias_path, dent->d_name, status);
//run_trigger = true;
}
done:
if (copy_path)
kfree(copy_path);
if (alias_path)
kfree(alias_path);
if (switch_path)
kfree(switch_path);
return status;
}
static
int run_bone(struct mars_peerinfo *peer, struct mars_dent *dent)
{
int status = 0;
struct kstat local_stat = {};
bool stat_ok;
bool update_mtime = true;
bool update_ctime = true;
bool run_trigger = false;
if (!strncmp(dent->d_name, ".tmp", 4)) {
goto done;
}
if (!strncmp(dent->d_name, "ignore", 6)) {
goto done;
}
status = mars_stat(dent->d_path, &local_stat, true);
stat_ok = (status >= 0);
if (stat_ok) {
update_mtime = timespec_compare(&dent->new_stat.mtime, &local_stat.mtime) > 0;
update_ctime = timespec_compare(&dent->new_stat.ctime, &local_stat.ctime) > 0;
//MARS_DBG("timestamps '%s' remote = %ld.%09ld local = %ld.%09ld\n", dent->d_path, dent->new_stat.mtime.tv_sec, dent->new_stat.mtime.tv_nsec, local_stat.mtime.tv_sec, local_stat.mtime.tv_nsec);
if ((dent->new_stat.mode & S_IRWXU) !=
(local_stat.mode & S_IRWXU) &&
update_ctime) {
mode_t newmode = local_stat.mode;
MARS_DBG("chmod '%s' 0x%xd -> 0x%xd\n", dent->d_path, newmode & S_IRWXU, dent->new_stat.mode & S_IRWXU);
newmode &= ~S_IRWXU;
newmode |= (dent->new_stat.mode & S_IRWXU);
mars_chmod(dent->d_path, newmode);
run_trigger = true;
}
if (dent->new_stat.uid != local_stat.uid && update_ctime) {
MARS_DBG("lchown '%s' %d -> %d\n", dent->d_path, local_stat.uid, dent->new_stat.uid);
mars_lchown(dent->d_path, dent->new_stat.uid);
run_trigger = true;
}
}
if (S_ISDIR(dent->new_stat.mode)) {
if (!_is_usable_dir(dent->d_name)) {
MARS_DBG("ignoring directory '%s'\n", dent->d_path);
goto done;
}
if (!stat_ok) {
status = mars_mkdir(dent->d_path);
MARS_DBG("create directory '%s' status = %d\n", dent->d_path, status);
if (status >= 0) {
mars_chmod(dent->d_path, dent->new_stat.mode);
mars_lchown(dent->d_path, dent->new_stat.uid);
}
}
} else if (S_ISLNK(dent->new_stat.mode) && dent->new_link) {
if (!stat_ok || update_mtime) {
status = mars_symlink(dent->new_link, dent->d_path, &dent->new_stat.mtime, dent->new_stat.uid);
MARS_DBG("create symlink '%s' -> '%s' status = %d\n", dent->d_path, dent->new_link, status);
run_trigger = true;
}
} else if (S_ISREG(dent->new_stat.mode) && _is_peer_logfile(dent->d_name, my_id())) {
const char *parent_path = backskip_replace(dent->d_path, '/', false, "");
if (likely(parent_path)) {
struct mars_dent *parent = mars_find_dent(peer->global, parent_path);
if (unlikely(!parent)) {
MARS_DBG("ignoring non-existing local resource '%s'\n", parent_path);
} else {
status = check_logfile(peer, dent, parent, local_stat.size);
}
kfree(parent_path);
}
} else {
MARS_DBG("ignoring '%s'\n", dent->d_path);
}
done:
if (status >= 0) {
status = run_trigger ? 1 : 0;
}
return status;
}
static
int run_bones(struct mars_peerinfo *peer)
{
LIST_HEAD(tmp_list);
struct list_head *tmp;
unsigned long flags;
bool run_trigger = false;
int status = 0;
traced_lock(&peer->lock, flags);
list_replace_init(&peer->remote_dent_list, &tmp_list);
traced_unlock(&peer->lock, flags);
for (tmp = tmp_list.next; tmp != &tmp_list; tmp = tmp->next) {
struct mars_dent *dent = container_of(tmp, struct mars_dent, dent_link);
if (!dent->d_path) {
MARS_DBG("NULL\n");
continue;
}
//MARS_DBG("path = '%s'\n", dent->d_path);
status = run_bone(peer, dent);
if (status > 0)
run_trigger = true;
//MARS_DBG("path = '%s' worker status = %d\n", dent->d_path, status);
}
mars_free_dent_all(&tmp_list);
#if 0
if (run_trigger) {
mars_trigger();
}
#endif
return status;
}
///////////////////////////////////////////////////////////////////////
// remote working infrastructure
static
void _peer_cleanup(struct mars_peerinfo *peer)
{
if (peer->socket) {
kernel_sock_shutdown(peer->socket, SHUT_WR);
peer->socket = NULL;
}
//...
}
static
int remote_thread(void *data)
{
struct mars_peerinfo *peer = data;
char *real_peer;
struct sockaddr_storage sockaddr = {};
int status;
if (!peer)
return -1;
real_peer = mars_translate_hostname(peer->global, peer->peer);
MARS_INF("-------- remote thread starting on peer '%s' (%s)\n", peer->peer, real_peer);
//fake_mm();
status = mars_create_sockaddr(&sockaddr, real_peer);
if (unlikely(status < 0)) {
MARS_ERR("unusable remote address '%s' (%s)\n", real_peer, peer->peer);
goto done;
}
while (!kthread_should_stop()) {
LIST_HEAD(tmp_list);
LIST_HEAD(old_list);
unsigned long flags;
struct mars_cmd cmd = {
.cmd_code = CMD_GETENTS,
.cmd_str1 = peer->path,
.cmd_int1 = peer->maxdepth,
};
if (!peer->socket) {
status = mars_create_socket(&peer->socket, &sockaddr, false);
if (unlikely(status < 0)) {
peer->socket = NULL;
MARS_INF("no connection to '%s'\n", real_peer);
msleep(5000);
continue;
}
MARS_DBG("successfully opened socket to '%s'\n", real_peer);
continue;
}
status = mars_send_struct(&peer->socket, &cmd, mars_cmd_meta);
if (unlikely(status < 0)) {
MARS_ERR("communication error on send, status = %d\n", status);
_peer_cleanup(peer);
msleep(5000);
continue;
}
status = mars_recv_dent_list(&peer->socket, &tmp_list);
if (unlikely(status < 0)) {
MARS_ERR("communication error on receive, status = %d\n", status);
_peer_cleanup(peer);
msleep(5000);
continue;
}
if (list_empty(&tmp_list)) {
msleep(5000);
continue;
}
//MARS_DBG("AHA!!!!!!!!!!!!!!!!!!!!\n");
traced_lock(&peer->lock, flags);
list_replace_init(&peer->remote_dent_list, &old_list);
list_replace_init(&tmp_list, &peer->remote_dent_list);
traced_unlock(&peer->lock, flags);
mars_free_dent_all(&old_list);
if (!kthread_should_stop())
msleep(10 * 1000);
}
MARS_INF("-------- remote thread terminating\n");
_peer_cleanup(peer);
done:
//cleanup_mm();
peer->thread = NULL;
if (real_peer)
kfree(real_peer);
return 0;
}
///////////////////////////////////////////////////////////////////////
// helpers for worker functions
static int _kill_peer(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
struct mars_peerinfo *peer = dent->d_private;
if (global->global_power.button) {
return 0;
}
if (!peer) {
return 0;
}
if (!peer->thread) {
MARS_ERR("oops, remote thread is not running - doing cleanup myself\n");
_peer_cleanup(peer);
dent->d_private = NULL;
return -1;
}
kthread_stop(peer->thread);
dent->d_private = NULL;
return 0;
}
static int _make_peer(struct mars_global *global, struct mars_dent *dent, char *mypeer, char *path)
{
static int serial = 0;
struct mars_peerinfo *peer;
int status = 0;
if (!global->global_power.button || !dent->new_link) {
return 0;
}
if (!mypeer) {
status = _parse_args(dent, dent->new_link, 1);
if (status < 0)
goto done;
mypeer = dent->d_argv[0];
}
MARS_DBG("peer '%s'\n", mypeer);
if (!dent->d_private) {
dent->d_private = kzalloc(sizeof(struct mars_peerinfo), GFP_MARS);
if (!dent->d_private) {
MARS_ERR("no memory for peer structure\n");
return -1;
}
peer = dent->d_private;
peer->global = global;
peer->peer = mypeer;
peer->path = path;
peer->maxdepth = 2;
spin_lock_init(&peer->lock);
INIT_LIST_HEAD(&peer->remote_dent_list);
//init_waitqueue_head(&peer->event);
}
peer = dent->d_private;
if (!peer->thread) {
peer->thread = kthread_create(remote_thread, peer, "mars_remote%d", serial++);
if (unlikely(IS_ERR(peer->thread))) {
MARS_ERR("cannot start peer thread, status = %d\n", (int)PTR_ERR(peer->thread));
peer->thread = NULL;
return -1;
}
MARS_DBG("starting peer thread\n");
wake_up_process(peer->thread);
}
status = run_bones(peer);
done:
return status;
}
static int kill_scan(void *buf, struct mars_dent *dent)
{
return _kill_peer(buf, dent);
}
static int make_scan(void *buf, struct mars_dent *dent)
{
MARS_DBG("path = '%s' peer = '%s'\n", dent->d_path, dent->d_rest);
// don't connect to myself
if (!strcmp(dent->d_rest, my_id())) {
return 0;
}
return _make_peer(buf, dent, dent->d_rest, "/mars");
}
static
int kill_all(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
if (global->global_power.button) {
return 0;
}
MARS_DBG("killing dent = '%s'\n", dent->d_path);
mars_kill_dent(dent);
return 0;
}
///////////////////////////////////////////////////////////////////////
// handlers / helpers for logfile rotation
struct mars_rotate {
struct mars_global *global;
struct mars_dent *replay_link;
struct mars_dent *aio_dent;
struct aio_brick *aio_brick;
struct mars_info aio_info;
struct trans_logger_brick *trans_brick;
struct mars_dent *relevant_log;
struct mars_brick *relevant_brick;
struct mars_dent *current_log;
struct mars_dent *prev_log;
struct mars_dent *next_log;
long long last_jiffies;
loff_t start_pos;
loff_t end_pos;
int max_sequence;
bool has_error;
bool do_replay;
bool is_primary;
};
static
void _create_new_logfile(const char *path)
{
struct file *f;
const int flags = O_RDWR | O_CREAT | O_EXCL;
const int prot = 0600;
mm_segment_t oldfs;
oldfs = get_fs();
set_fs(get_ds());
f = filp_open(path, flags, prot);
set_fs(oldfs);
if (IS_ERR(f)) {
int err = PTR_ERR(f);
if (err == -EEXIST) {
MARS_INF("logfile '%s' already exists\n", path);
} else {
MARS_ERR("could not create logfile '%s' status = %d\n", path, err);
}
} else {
MARS_DBG("created empty logfile '%s'\n", path);
filp_close(f, NULL);
mars_trigger();
}
}
static
int _update_replaylink(struct mars_dent *parent, int sequence, loff_t pos, bool check_exist)
{
struct timespec now = {};
char *old;
char *new;
int status = -ENOMEM;
if (check_exist) {
struct kstat kstat;
char *test = path_make("%s/log-%09d-%s", parent->d_path, sequence, my_id());
if (!test) {
goto out_old;
}
status = mars_stat(test, &kstat, true);
kfree(test);
if (status < 0) {
MARS_DBG("could not update replay link to nonexisting logfile %09d\n", sequence);
goto out_old;
}
status = -ENOMEM;
}
old = path_make("log-%09d-%s,%lld", sequence, my_id(), pos);
if (!old) {
goto out_old;
}
new = path_make("%s/replay-%s", parent->d_path, my_id());
if (!new) {
goto out_new;
}
get_lamport(&now);
status = mars_symlink(old, new, &now, 0);
if (status < 0) {
MARS_ERR("cannot create symlink '%s' -> '%s' status = %d\n", old, new, status);
} else {
MARS_DBG("make replay symlink '%s' -> '%s' status = %d\n", old, new, status);
}
kfree(new);
out_new:
kfree(old);
out_old:
return status;
}
/* This must be called once at every round of logfile checking.
*/
static
int make_log_init(void *buf, struct mars_dent *parent)
{
struct mars_global *global = buf;
struct mars_brick *aio_brick;
struct mars_brick *trans_brick;
struct mars_rotate *rot = parent->d_private;
struct mars_dent *replay_link;
struct mars_dent *aio_dent;
struct mars_output *output;
const char *replay_path = NULL;
const char *aio_path = NULL;
const char *switch_path = NULL;
int status;
if (!rot) {
rot = kzalloc(sizeof(struct mars_rotate), GFP_MARS);
parent->d_private = rot;
if (!rot) {
MARS_ERR("cannot allocate rot structure\n");
status = -ENOMEM;
goto done;
}
rot->global = global;
}
rot->replay_link = NULL;
rot->aio_dent = NULL;
rot->aio_brick = NULL;
rot->relevant_log = NULL;
rot->relevant_brick = NULL;
rot->prev_log = NULL;
rot->next_log = NULL;
rot->max_sequence = 0;
rot->has_error = false;
/* Fetch the replay status symlink.
* It must exist, and its value will control everything.
*/
replay_path = path_make("%s/replay-%s", parent->d_path, my_id());
if (unlikely(!replay_path)) {
MARS_ERR("cannot make path\n");
status = -ENOMEM;
goto done;
}
replay_link = (void*)mars_find_dent(global, replay_path);
if (unlikely(!replay_link || !replay_link->new_link)) {
MARS_DBG("replay status symlink '%s' does not exist (%p)\n", replay_path, replay_link);
status = -ENOENT;
goto done;
}
status = _parse_args(replay_link, replay_link->new_link, 2);
if (unlikely(status < 0)) {
goto done;
}
rot->replay_link = replay_link;
/* Fetch the referenced AIO dentry.
*/
aio_path = path_make("%s/%s", parent->d_path, replay_link->d_argv[0]);
if (unlikely(!aio_path)) {
MARS_ERR("cannot make path\n");
status = -ENOMEM;
goto done;
}
aio_dent = (void*)mars_find_dent(global, aio_path);
if (unlikely(!aio_dent)) {
MARS_DBG("logfile '%s' does not exist\n", aio_path);
status = -ENOENT;
if (rot->is_primary) { // try to create an empty logfile
_create_new_logfile(aio_path);
}
goto done;
}
rot->aio_dent = aio_dent;
/* Fetch / make the AIO brick instance
*/
aio_brick =
make_brick_all(global,
aio_dent,
NULL,
NULL,
10 * HZ,
aio_path,
(const struct generic_brick_type*)&aio_brick_type,
(const struct generic_brick_type*[]){},
NULL,
"%s/%s",
(const char *[]){},
0,
parent->d_path,
replay_link->d_argv[0]);
if (!aio_brick) {
MARS_ERR("cannot access '%s'\n", aio_path);
status = -EIO;
goto done;
}
rot->aio_brick = (void*)aio_brick;
/* Fetch the actual logfile size
*/
output = aio_brick->outputs[0];
status = output->ops->mars_get_info(output, &rot->aio_info);
if (status < 0) {
MARS_ERR("cannot get info on '%s'\n", aio_path);
goto done;
}
MARS_DBG("logfile '%s' size = %lld\n", aio_path, rot->aio_info.current_size);
// check whether attach is allowed
switch_path = path_make("%s/switch-%s/attach", parent->d_path, my_id());
/* Fetch / make the transaction logger.
* We deliberately "forget" to connect the log input here.
* Will be carried out later in make_log().
* The final switch-on will be started in make_log_finalize().
*/
trans_brick =
make_brick_all(global,
parent,
_set_trans_params,
NULL,
0,
aio_path,
(const struct generic_brick_type*)&trans_logger_brick_type,
(const struct generic_brick_type*[]){NULL},
switch_path,
"%s/logger",
(const char *[]){"%s/data-%s"},
1,
parent->d_path,
parent->d_path,
my_id());
status = -ENOENT;
if (!trans_brick) {
goto done;
}
rot->trans_brick = (void*)trans_brick;
/* For safety, default is to try an (unnecessary) replay in case
* something goes wrong later.
*/
rot->do_replay = true;
status = 0;
done:
if (aio_path)
kfree(aio_path);
if (replay_path)
kfree(replay_path);
if (switch_path)
kfree(switch_path);
return status;
}
/* Internal helper. Return codes:
* ret < 0 : error
* ret == 0 : not relevant
* ret == 1 : relevant, no transaction replay
* ret == 2 : relevant for transaction replay
* ret == 3 : relevant for appending
*/
static
int _check_logging_status(struct mars_global *global, struct mars_dent *dent, long long *oldpos, long long *newpos)
{
struct mars_dent *parent = dent->d_parent;
struct mars_rotate *rot = parent->d_private;
int status = -EINVAL;
CHECK_PTR(rot, done);
status = 0;
if (!rot->replay_link || !rot->aio_dent || !rot->aio_brick) {
//MARS_DBG("nothing to do on '%s'\n", dent->d_path);
goto done;
}
if (rot->aio_dent->d_serial != dent->d_serial) {
//MARS_DBG("serial number %d not relevant\n", dent->d_serial);
goto done;
}
if (sscanf(rot->replay_link->d_argv[1], "%lld", oldpos) != 1) {
MARS_ERR("bad position argument '%s'\n", rot->replay_link->d_argv[1]);
status = -EINVAL;
goto done;
}
if (unlikely(rot->aio_info.current_size < *oldpos)) {
MARS_ERR("oops, bad replay position attempted in logfile '%s' (file length %lld should never be smaller than requested position %lld, is your filesystem corrupted?) => please repair this by hand\n", rot->aio_dent->d_path, rot->aio_info.current_size, *oldpos);
status = -EINVAL;
goto done;
}
if (rot->aio_info.current_size > *oldpos) {
MARS_DBG("transaction log replay is necessary on '%s' from %lld to %lld\n", rot->aio_dent->d_path, *oldpos, rot->aio_info.current_size);
*newpos = rot->aio_info.current_size;
status = 2;
} else if (rot->aio_info.current_size > 0) {
MARS_DBG("transaction log '%s' is already applied (would be usable for appending at position %lld, but a fresh log is needed for safety reasons)\n", rot->aio_dent->d_path, *oldpos);
*newpos = rot->aio_info.current_size;
status = 1;
} else if (!rot->is_primary) {
MARS_DBG("empty transaction log '%s' would be usable, but I am not primary\n", rot->aio_dent->d_path);
status = 0;
} else {
MARS_DBG("empty transaction log '%s' is usable for me as a primary node\n", rot->aio_dent->d_path);
status = 3;
}
done:
return status;
}
/* Note: this is strictly called in d_serial order.
* This is important!
*/
static
int make_log(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
struct mars_dent *parent = dent->d_parent;
struct mars_rotate *rot = parent->d_private;
struct trans_logger_brick *trans_brick;
struct mars_dent *prev_log;
loff_t start_pos = 0;
loff_t end_pos = 0;
int status = -EINVAL;
CHECK_PTR(rot, err);
status = 0;
trans_brick = rot->trans_brick;
if (!global->global_power.button || !dent->d_parent || !trans_brick || rot->has_error) {
MARS_DBG("nothing to do rot_error = %d\n", rot->has_error);
goto done;
}
if (dent->d_serial > rot->max_sequence) {
rot->max_sequence = dent->d_serial;
}
/* Check for consecutiveness of logfiles
*/
prev_log = rot->next_log;
if (prev_log && prev_log->d_serial + 1 != dent->d_serial) {
MARS_ERR("transaction logs are not consecutive at '%s' (%d ~> %d)\n", dent->d_path, prev_log->d_serial, dent->d_serial);
status = -EINVAL;
goto done;
}
/* Skip any logfiles after the relevant one.
* This should happen only when replaying multiple logfiles
* in sequence, or when starting a new logfile for writing.
*/
if (rot->relevant_log) {
if (rot->do_replay) {
status = 0;
goto ok;
}
if (rot->aio_dent->new_stat.size > 0) {
MARS_ERR("oops, the new logfile '%s' is not empty -- for safety, I will not use it -- log rotation is disabled now\n", dent->d_path);
status = -EINVAL;
goto done;
}
MARS_DBG("considering next logfile '%s' for rotation\n", dent->d_path);
}
/* Find current logging status.
*/
status = _check_logging_status(global, dent, &start_pos, &end_pos);
if (status < 0) {
goto done;
}
/* Relevant or not?
*/
switch (status) {
case 0: // not relevant
goto ok;
case 1: /* Relevant, and transaction replay already finished.
* When primary, switch over to a new logfile.
*/
if (!trans_brick->power.button && !trans_brick->power.led_on && trans_brick->power.led_off) {
_update_replaylink(dent->d_parent, dent->d_serial + 1, 0, !rot->is_primary);
trans_brick->current_pos = 0;
rot->last_jiffies = jiffies;
mars_trigger();
}
status = -EAGAIN;
goto done;
case 2: // relevant for transaction replay
MARS_DBG("replaying transaction log '%s' from %lld to %lld\n", dent->d_path, start_pos, end_pos);
rot->do_replay = true;
rot->start_pos = start_pos;
rot->end_pos = end_pos;
rot->relevant_log = dent;
break;
case 3: // relevant for appending
MARS_DBG("appending to transaction log '%s'\n", dent->d_path);
rot->do_replay = false;
rot->start_pos = 0;
rot->end_pos = 0;
rot->relevant_log = dent;
break;
default:
MARS_ERR("bad internal status %d\n", status);
status = -EINVAL;
goto done;
}
ok:
/* All ok: switch over the indicators.
*/
rot->prev_log = rot->next_log;
rot->next_log = dent;
done:
if (status < 0) {
MARS_DBG("rot_error status = %d\n", status);
rot->has_error = true;
}
err:
return status;
}
static
int _start_trans(struct mars_rotate *rot)
{
struct trans_logger_brick *trans_brick = rot->trans_brick;
int status = 0;
if (trans_brick->power.button || !trans_brick->power.led_off) {
goto done;
}
/* Internal safety checks
*/
status = -EINVAL;
if (unlikely(!rot->aio_brick || !rot->relevant_log)) {
MARS_ERR("something is missing, this should not happen\n");
goto done;
}
if (unlikely(rot->relevant_brick)) {
MARS_ERR("log aio brick already present, this should not happen\n");
goto done;
}
/* For safety, disconnect old connection first
*/
if (trans_brick->inputs[1]->connect) {
(void)generic_disconnect((void*)trans_brick->inputs[1]);
}
/* Open new transaction log
*/
rot->relevant_brick =
make_brick_all(rot->global,
rot->relevant_log,
NULL,
NULL,
10 * HZ,
rot->relevant_log->d_path,
(const struct generic_brick_type*)&aio_brick_type,
(const struct generic_brick_type*[]){},
NULL,
rot->relevant_log->d_path,
(const char *[]){},
0);
if (!rot->relevant_brick) {
MARS_ERR("log aio brick not open\n");
goto done;
}
/* Connect to new transaction log
*/
status = generic_connect((void*)trans_brick->inputs[1], (void*)rot->relevant_brick->outputs[0]);
if (status < 0) {
goto done;
}
/* Supply all relevant parameters
*/
trans_brick->sequence = rot->relevant_log->d_serial;
if ((trans_brick->do_replay = rot->do_replay)) {
trans_brick->replay_start_pos = rot->start_pos;
trans_brick->replay_end_pos = rot->end_pos;
} else {
trans_brick->log_start_pos = rot->start_pos;
}
/* Switch on....
*/
status = mars_power_button((void*)trans_brick, true, false);
MARS_DBG("status = %d\n", status);
done:
return status;
}
static
int _stop_trans(struct mars_rotate *rot)
{
struct trans_logger_brick *trans_brick = rot->trans_brick;
int status = 0;
if (!trans_brick || !trans_brick->power.button) {
goto done;
}
/* Switch off temporarily....
*/
status = mars_power_button((void*)trans_brick, false, false);
MARS_DBG("status = %d\n", status);
if (status < 0 || !trans_brick->power.led_off) {
goto done;
}
/* Disconnect old connection
*/
if (trans_brick->inputs[1] && trans_brick->inputs[1]->connect) {
(void)generic_disconnect((void*)trans_brick->inputs[1]);
}
done:
return status;
}
static
int make_log_finalize(struct mars_global *global, struct mars_dent *parent)
{
struct mars_rotate *rot = parent->d_private;
struct trans_logger_brick *trans_brick;
int status = -EINVAL;
CHECK_PTR(rot, done);
trans_brick = rot->trans_brick;
status = 0;
if (!trans_brick) {
MARS_DBG("nothing to do\n");
goto done;
}
/* Stopping is also possible in case of errors
*/
if (trans_brick->power.button && trans_brick->power.led_on && !trans_brick->power.led_off) {
bool do_stop =
trans_brick->do_replay ?
(trans_brick->replay_pos == trans_brick->replay_end_pos || trans_brick->replay_code != -EAGAIN) :
(rot->relevant_log && rot->relevant_log != rot->current_log);
MARS_DBG("do_stop = %d\n", (int)do_stop);
if (do_stop || (long long)jiffies > rot->last_jiffies + 5 * HZ) {
status = _update_replaylink(parent, trans_brick->sequence, trans_brick->replay_pos, true);
rot->last_jiffies = jiffies;
}
if (do_stop) {
status = _stop_trans(rot);
}
goto done;
}
/* Special case: when no logfile exists,
* create one. This is an exception from the rule that
* normally userspace should control what happens in MARS.
*/
if (!rot->relevant_log && rot->is_primary && !rot->has_error && rot->max_sequence > 0) { // try to create an empty logfile
char *tmp = path_make("%s/log-%09d-%s", parent->d_path, rot->max_sequence + 1, my_id());
if (likely(tmp)) {
_create_new_logfile(tmp);
kfree(tmp);
msleep(1000);
goto done;
}
}
/* Starting is only possible when no error ocurred.
*/
if (!rot->relevant_log || rot->has_error) {
MARS_DBG("nothing to do\n");
goto done;
}
/* Start when necessary
*/
if (!trans_brick->power.button && !trans_brick->power.led_on && trans_brick->power.led_off) {
bool do_start = (!rot->do_replay || rot->start_pos != rot->end_pos);
MARS_DBG("do_start = %d\n", (int)do_start);
if (do_start) {
status = _start_trans(rot);
rot->current_log = rot->relevant_log;
}
} else {
MARS_DBG("trans_brick %d %d %d\n", trans_brick->power.button, trans_brick->power.led_on, trans_brick->power.led_off);
}
done:
return status;
}
///////////////////////////////////////////////////////////////////////
// specific handlers
static
int make_primary(void *buf, struct mars_dent *dent)
{
struct mars_dent *parent;
struct mars_rotate *rot;
int status = -EINVAL;
parent = dent->d_parent;
CHECK_PTR(parent, done);
rot = parent->d_private;
CHECK_PTR(rot, done);
rot->is_primary = (dent->new_link && !strcmp(dent->new_link, my_id()));
status = 0;
done:
return status;
}
static
int make_bio(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
struct mars_brick *brick;
int status = 0;
if (!global->global_power.button) {
goto done;
}
if (mars_find_brick(global, NULL, dent->d_path)) {
goto done;
}
brick =
make_brick_all(global,
dent,
_set_bio_params,
NULL,
10 * HZ,
dent->d_path,
(const struct generic_brick_type*)&bio_brick_type,
(const struct generic_brick_type*[]){},
NULL,
dent->d_path,
(const char *[]){},
0);
if (unlikely(!brick)) {
status = -ENXIO;
goto done;
}
brick->outputs[0]->output_name = dent->d_path;
status = mars_power_button((void*)brick, true, false);
if (status < 0) {
kill_all(buf, dent);
}
done:
return status;
}
static int make_dev(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
struct mars_dent *parent = dent->d_parent;
struct mars_rotate *rot;
struct mars_brick *dev_brick;
struct if_brick *_dev_brick;
int status = 0;
if (!global->global_power.button || !parent || !dent->new_link) {
MARS_DBG("nothing to do\n");
goto done;
}
status = make_log_finalize(global, parent);
if (status < 0) {
MARS_DBG("logger not initialized\n");
goto done;
}
rot = parent->d_private;
if (!rot || !rot->is_primary) {
MARS_DBG("I am not primary, don't show the device\n");
goto done;
}
if (!rot->trans_brick || rot->trans_brick->do_replay || !rot->trans_brick->power.led_on || rot->trans_brick->power.led_off) {
MARS_DBG("transaction logger not ready for writing\n");
goto done;
}
status = _parse_args(dent, dent->new_link, 1);
if (status < 0) {
MARS_DBG("fail\n");
goto done;
}
dev_brick =
make_brick_all(global,
dent,
_set_if_params,
NULL,
10 * HZ,
dent->d_argv[0],
(const struct generic_brick_type*)&if_brick_type,
(const struct generic_brick_type*[]){(const struct generic_brick_type*)&trans_logger_brick_type},
NULL, // maybe we could allow switching here
"%s/linuxdev-%s",
(const char *[]){"%s/logger"},
1,
parent->d_path,
dent->d_argv[0],
parent->d_path);
if (!dev_brick) {
MARS_DBG("fail\n");
return -1;
}
dev_brick->status_level = 1;
_dev_brick = (void*)dev_brick;
#if 0
if (_dev_brick->has_closed) {
_dev_brick->has_closed = false;
MARS_INF("rotating logfile for '%s'\n", parent->d_name);
status = mars_power_button((void*)rot->trans_brick, false);
rot->relevant_log = NULL;
}
#endif
done:
return status;
}
static int _make_direct(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
struct mars_brick *brick;
char *src_path = NULL;
int status;
bool do_dealloc = false;
if (!global->global_power.button || !dent->d_parent || !dent->new_link) {
return 0;
}
status = _parse_args(dent, dent->new_link, 2);
if (status < 0) {
MARS_DBG("parse status = %d\n", status);
goto done;
}
src_path = dent->d_argv[0];
if (src_path[0] != '/') {
src_path = path_make("%s/%s", dent->d_parent->d_path, dent->d_argv[0]);
do_dealloc = true;
}
brick =
make_brick_all(global,
dent,
_set_bio_params,
NULL,
10 * HZ,
src_path,
(const struct generic_brick_type*)&bio_brick_type,
(const struct generic_brick_type*[]){},
NULL,
"%s",
(const char *[]){},
0,
src_path);
status = -1;
if (!brick) {
MARS_DBG("fail\n");
goto done;
}
brick =
make_brick_all(global,
dent,
_set_if_params,
NULL,
10 * HZ,
dent->d_argv[1],
(const struct generic_brick_type*)&if_brick_type,
(const struct generic_brick_type*[]){NULL},
NULL,
"%s/linuxdev-%s",
(const char *[]){ "%s" },
1,
dent->d_parent->d_path,
dent->d_argv[1],
src_path);
status = -1;
if (!brick) {
MARS_DBG("fail\n");
goto done;
}
status = 0;
done:
MARS_DBG("status = %d\n", status);
if (do_dealloc)
kfree(src_path);
return status;
}
static int _make_copy(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
const char *switch_path = NULL;
const char *copy_path = NULL;
int status;
if (!global->global_power.button || !dent->d_parent || !dent->new_link) {
return 0;
}
status = _parse_args(dent, dent->new_link, 2);
if (status < 0) {
goto done;
}
copy_path = backskip_replace(dent->d_path, '/', true, "/copy-");
if (unlikely(!copy_path)) {
status = -ENOMEM;
goto done;
}
// check whether connection is allowed
switch_path = path_make("%s/switch-%s/connect", dent->d_parent->d_path, my_id());
status = __make_copy(global, dent, switch_path, copy_path, dent->d_parent->d_path, (const char**)dent->d_argv, -1, NULL);
done:
MARS_DBG("status = %d\n", status);
if (copy_path)
kfree(copy_path);
if (switch_path)
kfree(switch_path);
return status;
}
static int make_sync(void *buf, struct mars_dent *dent)
{
struct mars_global *global = buf;
loff_t start_pos = 0;
struct mars_dent *connect_dent;
char *peer;
struct copy_brick *copy = NULL;
char *tmp = NULL;
const char *switch_path = NULL;
const char *copy_path = NULL;
const char *src = NULL;
const char *dst = NULL;
int status;
if (!global->global_power.button || !dent->d_parent || !dent->new_link) {
return 0;
}
/* Analyze replay position
*/
status = sscanf(dent->new_link, "%lld", &start_pos);
if (status != 1) {
MARS_ERR("bad syncstatus symlink syntax '%s' (%s)\n", dent->new_link, dent->d_path);
status = -EINVAL;
goto done;
}
/* Determine peer
*/
tmp = path_make("%s/connect-%s", dent->d_parent->d_path, my_id());
status = -ENOMEM;
if (unlikely(!tmp))
goto done;
connect_dent = (void*)mars_find_dent(global, tmp);
if (!connect_dent || !connect_dent->new_link) {
MARS_ERR("cannot determine peer, symlink '%s' is missing\n", tmp);
status = -ENOENT;
goto done;
}
peer = connect_dent->new_link;
/* Start copy
*/
src = path_make("data-%s@%s", peer, peer);
dst = path_make("data-%s", my_id());
copy_path = backskip_replace(dent->d_path, '/', true, "/copy-");
status = -ENOMEM;
if (unlikely(!src || !dst || !copy_path))
goto done;
// check whether connection is allowed
switch_path = path_make("%s/switch-%s/sync", dent->d_parent->d_path, my_id());
MARS_DBG("starting initial sync '%s' => '%s'\n", src, dst);
{
const char *argv[2] = { src, dst };
status = __make_copy(global, dent, switch_path, copy_path, dent->d_parent->d_path, argv, start_pos, &copy);
}
/* Update syncstatus symlink
*/
if (status >= 0 && copy && copy->power.button && copy->power.led_on) {
kfree(src);
kfree(dst);
src = path_make("%lld", copy->copy_last);
dst = path_make("%s/syncstatus-%s", dent->d_parent->d_path, my_id());
status = -ENOMEM;
if (unlikely(!src || !dst))
goto done;
status = mars_symlink(src, dst, NULL, 0);
}
done:
MARS_DBG("status = %d\n", status);
if (tmp)
kfree(tmp);
if (src)
kfree(src);
if (dst)
kfree(dst);
if (copy_path)
kfree(copy_path);
if (switch_path)
kfree(switch_path);
return status;
}
///////////////////////////////////////////////////////////////////////
// the order is important!
enum {
// root element: this must have index 0
CL_ROOT,
// replacement for DNS in kernelspace
CL_IPS,
CL_PEERS,
// resource definitions
CL_RESOURCE,
CL_SWITCH,
CL_SWITCH_ITEMS,
CL_CONNECT,
CL_DATA,
CL_PRIMARY,
CL__FILE,
CL_SYNC,
CL__COPY,
CL__DIRECT,
CL_REPLAYSTATUS,
CL_LOG,
CL_DEVICE,
};
/* Please keep the order the same as in the enum.
*/
static const struct light_class light_classes[] = {
/* Placeholder for root node /mars/
*/
[CL_ROOT] = {
},
/* Directory containing the addresses of all peers
*/
[CL_IPS] = {
.cl_name = "ips",
.cl_len = 3,
.cl_type = 'd',
.cl_father = CL_ROOT,
},
/* Anyone participating in a MARS cluster must
* be named here (symlink pointing to the IP address).
* We have no DNS in kernel space.
*/
[CL_PEERS] = {
.cl_name = "ip-",
.cl_len = 3,
.cl_type = 'l',
.cl_father = CL_IPS,
#if 1
.cl_forward = make_scan,
.cl_backward = kill_scan,
#endif
},
/* Directory containing all items of a resource
*/
[CL_RESOURCE] = {
.cl_name = "resource-",
.cl_len = 9,
.cl_type = 'd',
.cl_father = CL_ROOT,
.cl_forward = make_log_init,
.cl_backward = NULL,
},
/* Subdirectory for controlling items...
*/
[CL_SWITCH] = {
.cl_name = "switch-",
.cl_len = 7,
.cl_type = 'd',
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = NULL,
.cl_backward = NULL,
},
/* ... and its contents
*/
[CL_SWITCH_ITEMS] = {
.cl_name = "",
.cl_len = 0, // catch any
.cl_type = 'l',
.cl_father = CL_SWITCH,
.cl_forward = NULL,
.cl_backward = NULL,
},
/* Symlink indicating the current peer
*/
[CL_CONNECT] = {
.cl_name = "connect-",
.cl_len = 8,
.cl_type = 'l',
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = NULL,
.cl_backward = NULL,
},
/* File or symlink to the real device / real (sparse) file
* when hostcontext is missing, the corresponding peer will
* not participate in that resource.
*/
[CL_DATA] = {
.cl_name = "data-",
.cl_len = 5,
.cl_type = 'F',
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = make_bio,
.cl_backward = kill_all,
},
/* Symlink pointing to the name of the primary node
*/
[CL_PRIMARY] = {
.cl_name = "primary",
.cl_len = 7,
.cl_type = 'l',
.cl_hostcontext = false,
.cl_father = CL_RESOURCE,
.cl_forward = make_primary,
.cl_backward = NULL,
},
/* Only for testing: open local file
*/
[CL__FILE] = {
.cl_name = "_file-",
.cl_len = 6,
.cl_type = 'F',
.cl_serial = true,
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = make_bio,
.cl_backward = kill_all,
},
/* symlink indicating the current status / end
* of initial data sync.
*/
[CL_SYNC] = {
.cl_name = "syncstatus-",
.cl_len = 11,
.cl_type = 'l',
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = make_sync,
.cl_backward = kill_all,
},
/* Only for testing: make a copy instance
*/
[CL__COPY] = {
.cl_name = "_copy-",
.cl_len = 6,
.cl_type = 'l',
.cl_serial = true,
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = _make_copy,
.cl_backward = kill_all,
},
/* Only for testing: access local data
*/
[CL__DIRECT] = {
.cl_name = "_direct-",
.cl_len = 8,
.cl_type = 'l',
.cl_serial = true,
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = _make_direct,
.cl_backward = kill_all,
},
/* Passive symlink indicating the last state of
* transaction log replay.
*/
[CL_REPLAYSTATUS] = {
.cl_name = "replay-",
.cl_len = 7,
.cl_type = 'l',
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
#if 0
.cl_forward = make_replay,
.cl_backward = kill_all,
#endif
},
/* Logfiles for transaction logger
*/
[CL_LOG] = {
.cl_name = "log-",
.cl_len = 4,
.cl_type = 'F',
.cl_serial = true,
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
#if 1
.cl_forward = make_log,
.cl_backward = kill_all,
#endif
},
/* Name of the device appearing at the primary
*/
[CL_DEVICE] = {
.cl_name = "device-",
.cl_len = 7,
.cl_type = 'l',
.cl_hostcontext = true,
.cl_father = CL_RESOURCE,
.cl_forward = make_dev,
.cl_backward = kill_all,
},
{}
};
/* Helper routine to pre-determine the relevance of a name from the filesystem.
*/
static int light_checker(struct mars_dent *parent, const char *_name, int namlen, unsigned int d_type, int *prefix, int *serial)
{
int class;
int status = -2;
#ifdef MARS_DEBUGGING
const char *name = kstrdup(_name, GFP_MARS);
if (!name)
return -ENOMEM;
#else
const char *name = _name;
#endif
//MARS_DBG("trying '%s' '%s'\n", path, name);
for (class = CL_ROOT + 1; ; class++) {
const struct light_class *test = &light_classes[class];
int len = test->cl_len;
if (!test->cl_name) { // end of table
break;
}
//MARS_DBG(" testing class '%s'\n", test->cl_name);
#ifdef MARS_DEBUGGING
if (len != strlen(test->cl_name)) {
MARS_ERR("internal table '%s' mismatch: %d != %d\n", test->cl_name, len, (int)strlen(test->cl_name));
len = strlen(test->cl_name);
}
#endif
if (test->cl_father &&
(!parent || parent->d_class != test->cl_father)) {
continue;
}
if (len > 0 &&
(namlen < len || memcmp(name, test->cl_name, len))) {
continue;
}
//MARS_DBG("path '%s/%s' matches class %d '%s'\n", path, name, class, test->cl_name);
// check special contexts
if (test->cl_serial) {
int plus = 0;
int count;
count = sscanf(name+len, "%d%n", serial, &plus);
if (count < 1) {
//MARS_DBG("'%s' serial number mismatch at '%s'\n", name, name+len);
status = -1;
goto done;
}
len += plus;
if (name[len] == '-')
len++;
}
if (prefix)
*prefix = len;
if (test->cl_hostcontext) {
if (memcmp(name+len, my_id(), namlen-len)) {
//MARS_DBG("context mismatch '%s' at '%s'\n", name, name+len);
status = -1;
goto done;
}
}
// all ok
status = class;
goto done;
}
//MARS_DBG("no match for '%s' '%s'\n", path, name);
done:
#ifdef MARS_DEBUGGING
if (name)
kfree(name);
#endif
return status;
}
/* Do some syntactic checks, then delegate work to the real worker functions
* from the light_classes[] table.
*/
static int light_worker(struct mars_global *global, struct mars_dent *dent, bool direction)
{
light_worker_fn worker;
int class = dent->d_class;
if (class < 0 || class >= sizeof(light_classes)/sizeof(struct light_class)) {
MARS_ERR_ONCE(dent, "bad internal class %d of '%s'\n", class, dent->d_path);
return -EINVAL;
}
switch (light_classes[class].cl_type) {
case 'd':
if (!S_ISDIR(dent->new_stat.mode)) {
MARS_ERR_ONCE(dent, "'%s' should be a directory, but is something else\n", dent->d_path);
return -EINVAL;
}
break;
case 'f':
if (!S_ISREG(dent->new_stat.mode)) {
MARS_ERR_ONCE(dent, "'%s' should be a regular file, but is something else\n", dent->d_path);
return -EINVAL;
}
break;
case 'F':
if (!S_ISREG(dent->new_stat.mode) && !S_ISLNK(dent->new_stat.mode)) {
MARS_ERR_ONCE(dent, "'%s' should be a regular file or a symlink, but is something else\n", dent->d_path);
return -EINVAL;
}
break;
case 'l':
if (!S_ISLNK(dent->new_stat.mode)) {
MARS_ERR_ONCE(dent, "'%s' should be a symlink, but is something else\n", dent->d_path);
return -EINVAL;
}
break;
}
if (likely(class > CL_ROOT)) {
int father = light_classes[class].cl_father;
if (father == CL_ROOT) {
if (unlikely(dent->d_parent)) {
MARS_ERR_ONCE(dent, "'%s' is not at the root of the hierarchy\n", dent->d_path);
return -EINVAL;
}
} else if (unlikely(!dent->d_parent || dent->d_parent->d_class != father)) {
MARS_ERR_ONCE(dent, "last component '%s' from '%s' is at the wrong position in the hierarchy (class = %d, parent_class = %d, parent = '%s')\n", dent->d_name, dent->d_path, father, dent->d_parent ? dent->d_parent->d_class : -9999, dent->d_parent ? dent->d_parent->d_path : "");
return -EINVAL;
}
}
if (direction) {
worker = light_classes[class].cl_backward;
} else {
worker = light_classes[class].cl_forward;
}
if (worker) {
int status;
//MARS_DBG("working %s on '%s' rest='%s'\n", direction ? "backward" : "forward", dent->d_path, dent->d_rest);
status = worker(global, (void*)dent);
MARS_DBG("worked %s on '%s', status = %d\n", direction ? "backward" : "forward", dent->d_path, status);
return status;
}
return 0;
}
void _show_status(struct mars_global *global)
{
struct list_head *tmp;
down(&global->mutex);
for (tmp = global->brick_anchor.next; tmp != &global->brick_anchor; tmp = tmp->next) {
struct mars_brick *test;
const char *path;
char *src;
char *dst;
int status;
test = container_of(tmp, struct mars_brick, global_brick_link);
if (test->status_level <= 0)
continue;
path = test->brick_path;
if (!path) {
MARS_DBG("bad path\n");
continue;
}
if (*path != '/') {
MARS_DBG("bogus path '%s'\n", path);
continue;
}
src = test->power.led_on ? "1" : "0";
dst = backskip_replace(path, '/', true, "/actual-%s/", my_id());
if (!dst)
continue;
status = mars_symlink(src, dst, NULL, 0);
MARS_DBG("status symlink '%s' -> '%s' status = %d\n", dst, src, status);
if (test->status_level > 1) {
char perc[8];
char *dst2 = path_make("%s.percent", dst);
if (likely(dst2)) {
snprintf(perc, sizeof(perc), "%d", test->power.percent_done);
status = mars_symlink(perc, dst2, NULL, 0);
MARS_DBG("percent symlink '%s' -> '%s' status = %d\n", dst2, src, status);
kfree(dst2);
}
}
kfree(dst);
}
up(&global->mutex);
}
#ifdef STAT_DEBUGGING
static
void _show_statist(struct mars_global *global)
{
struct list_head *tmp;
int dent_count = 0;
int brick_count = 0;
down(&global->mutex);
MARS_STAT("================================== dents:\n");
for (tmp = global->dent_anchor.next; tmp != &global->dent_anchor; tmp = tmp->next) {
struct mars_dent *dent;
dent = container_of(tmp, struct mars_dent, dent_link);
MARS_STAT("dent '%s'\n", dent->d_path);
dent_count++;
}
MARS_STAT("================================== bricks:\n");
for (tmp = global->brick_anchor.next; tmp != &global->brick_anchor; tmp = tmp->next) {
struct mars_brick *test;
int i;
test = container_of(tmp, struct mars_brick, global_brick_link);
if (brick_count) {
MARS_STAT("---------\n");
}
MARS_STAT("brick type = %s path = '%s' name = '%s' level = %d button = %d off = %d on = %d\n", test->type->type_name, test->brick_path, test->brick_name, test->status_level, test->power.button, test->power.led_off, test->power.led_on);
brick_count++;
if (test->ops && test->ops->brick_statistics) {
char *info = test->ops->brick_statistics(test, 0);
if (info) {
MARS_STAT("%s", info);
kfree(info);
}
}
for (i = 0; i < test->nr_inputs; i++) {
struct mars_input *input = test->inputs[i];
struct mars_output *output = input ? input->connect : NULL;
if (output) {
MARS_STAT(" input %d connected with %s path = '%s' name = '%s'\n", i, output->brick->type->type_name, output->brick->brick_path, output->brick->brick_name);
} else {
MARS_STAT(" input %d not connected\n", i);
}
}
}
up(&global->mutex);
MARS_INF("==================== STATISTICS: %d dents, %d bricks\n", dent_count, brick_count);
}
#endif
static int light_thread(void *data)
{
char *id = my_id();
int status = 0;
struct mars_global global = {
.dent_anchor = LIST_HEAD_INIT(global.dent_anchor),
.brick_anchor = LIST_HEAD_INIT(global.brick_anchor),
.global_power = {
.button = true,
},
.mutex = __SEMAPHORE_INITIALIZER(global.mutex, 1),
.main_event = __WAIT_QUEUE_HEAD_INITIALIZER(global.main_event),
};
mars_global = &global; // TODO: cleanup, avoid stack
if (!id || strlen(id) < 2) {
MARS_ERR("invalid hostname\n");
status = -EFAULT;
goto done;
}
//fake_mm();
MARS_INF("-------- starting as host '%s' ----------\n", id);
while (global.global_power.button || !list_empty(&global.brick_anchor)) {
int status;
global.global_power.button = !kthread_should_stop();
status = mars_dent_work(&global, "/mars", sizeof(struct mars_dent), light_checker, light_worker, &global, 3);
MARS_DBG("worker status = %d\n", status);
_show_status(&global);
#ifdef STAT_DEBUGGING
_show_statist(&global);
#endif
msleep(1000);
wait_event_interruptible_timeout(global.main_event, global.main_trigger, 30 * HZ);
global.main_trigger = false;
}
done:
MARS_INF("-------- cleaning up ----------\n");
mars_free_dent_all(&global.dent_anchor);
mars_global = NULL;
main_thread = NULL;
MARS_INF("-------- done status = %d ----------\n", status);
//cleanup_mm();
return status;
}
static void __exit exit_light(void)
{
// TODO: make this thread-safe.
struct task_struct *thread = main_thread;
if (thread) {
main_thread = NULL;
MARS_DBG("====================== stopping everything...\n");
kthread_stop_nowait(thread);
mars_trigger();
kthread_stop(thread);
put_task_struct(thread);
MARS_DBG("====================== stopped everything.\n");
}
}
static int __init init_light(void)
{
struct task_struct *thread;
thread = kthread_create(light_thread, NULL, "mars_light");
if (IS_ERR(thread)) {
return PTR_ERR(thread);
}
get_task_struct(thread);
main_thread = thread;
wake_up_process(thread);
#if 1 // quirk: bump the memory reserve limits. TODO: determine right values.
{
extern int min_free_kbytes;
min_free_kbytes *= 4;
setup_per_zone_wmarks();
}
#endif
return 0;
}
// force module loading
const void *dummy1 = &client_brick_type;
const void *dummy2 = &server_brick_type;
MODULE_DESCRIPTION("MARS Light");
MODULE_AUTHOR("Thomas Schoebel-Theuer <tst@1und1.de>");
MODULE_LICENSE("GPL");
module_init(init_light);
module_exit(exit_light);
Reference in New Issue View Git Blame Copy Permalink