static void userspace_dtr(struct dm_dirty_log *log)
{
struct log_c *lc = log->context;
if (lc->integrated_flush) {
/* flush workqueue */
if (atomic_read(&lc->sched_flush))
flush_delayed_work(&lc->flush_log_work);
destroy_workqueue(lc->dmlog_wq);
}
(void) dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_DTR,
NULL, 0, NULL, NULL);
if (lc->log_dev)
dm_put_device(lc->ti, lc->log_dev);
mempool_destroy(lc->flush_entry_pool);
kfree(lc->usr_argv_str);
kfree(lc);
return;
}
static int userspace_presuspend(struct dm_dirty_log *log)
{
int r;
struct log_c *lc = log->context;
r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_PRESUSPEND,
NULL, 0, NULL, NULL);
return r;
}
static int userspace_resume(struct dm_dirty_log *log)
{
int r;
struct log_c *lc = log->context;
lc->in_sync_hint = 0;
r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_RESUME,
NULL, 0, NULL, NULL);
return r;
}
static int userspace_do_request(struct log_c *lc, const char *uuid,
int request_type, char *data, size_t data_size,
char *rdata, size_t *rdata_size)
{
int r;
/*
* If the server isn't there, -ESRCH is returned,
* and we must keep trying until the server is
* restored.
*/
retry:
r = dm_consult_userspace(uuid, lc->luid, request_type, data,
data_size, rdata, rdata_size);
if (r != -ESRCH)
return r;
DMERR(" Userspace log server not found.");
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(2*HZ);
DMWARN("Attempting to contact userspace log server...");
r = dm_consult_userspace(uuid, lc->luid, DM_ULOG_CTR,
lc->usr_argv_str,
strlen(lc->usr_argv_str) + 1,
NULL, NULL);
if (!r)
break;
}
DMINFO("Reconnected to userspace log server... DM_ULOG_CTR complete");
r = dm_consult_userspace(uuid, lc->luid, DM_ULOG_RESUME, NULL,
0, NULL, NULL);
if (!r)
goto retry;
DMERR("Error trying to resume userspace log: %d", r);
return -ESRCH;
}
static void userspace_dtr(struct dm_dirty_log *log)
{
struct log_c *lc = log->context;
(void) dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_DTR,
NULL, 0,
NULL, NULL);
kfree(lc->usr_argv_str);
kfree(lc);
return;
}
static int userspace_postsuspend(struct dm_dirty_log *log)
{
int r;
struct log_c *lc = log->context;
/*
* Run planned flush earlier.
*/
if (lc->integrated_flush && atomic_read(&lc->sched_flush))
flush_delayed_work(&lc->flush_log_work);
r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_POSTSUSPEND,
NULL, 0, NULL, NULL);
return r;
}
/*
* userspace_ctr
*
* argv contains:
* <UUID> [integrated_flush] <other args>
* Where 'other args' are the userspace implementation-specific log
* arguments.
*
* Example:
* <UUID> [integrated_flush] clustered-disk <arg count> <log dev>
* <region_size> [[no]sync]
*
* This module strips off the <UUID> and uses it for identification
* purposes when communicating with userspace about a log.
*
* If integrated_flush is defined, the kernel combines flush
* and mark requests.
*
* The rest of the line, beginning with 'clustered-disk', is passed
* to the userspace ctr function.
*/
static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
unsigned argc, char **argv)
{
int r = 0;
int str_size;
char *ctr_str = NULL;
struct log_c *lc = NULL;
uint64_t rdata;
size_t rdata_size = sizeof(rdata);
char *devices_rdata = NULL;
size_t devices_rdata_size = DM_NAME_LEN;
if (argc < 3) {
DMWARN("Too few arguments to userspace dirty log");
return -EINVAL;
}
lc = kzalloc(sizeof(*lc), GFP_KERNEL);
if (!lc) {
DMWARN("Unable to allocate userspace log context.");
return -ENOMEM;
}
/* The ptr value is sufficient for local unique id */
lc->luid = (unsigned long)lc;
lc->ti = ti;
if (strlen(argv[0]) > (DM_UUID_LEN - 1)) {
DMWARN("UUID argument too long.");
kfree(lc);
return -EINVAL;
}
lc->usr_argc = argc;
strncpy(lc->uuid, argv[0], DM_UUID_LEN);
argc--;
argv++;
spin_lock_init(&lc->flush_lock);
INIT_LIST_HEAD(&lc->mark_list);
INIT_LIST_HEAD(&lc->clear_list);
if (!strcasecmp(argv[0], "integrated_flush")) {
lc->integrated_flush = 1;
argc--;
argv++;
}
str_size = build_constructor_string(ti, argc, argv, &ctr_str);
if (str_size < 0) {
kfree(lc);
return str_size;
}
devices_rdata = kzalloc(devices_rdata_size, GFP_KERNEL);
if (!devices_rdata) {
DMERR("Failed to allocate memory for device information");
r = -ENOMEM;
goto out;
}
lc->flush_entry_pool = mempool_create_slab_pool(FLUSH_ENTRY_POOL_SIZE,
_flush_entry_cache);
if (!lc->flush_entry_pool) {
DMERR("Failed to create flush_entry_pool");
r = -ENOMEM;
goto out;
}
/*
* Send table string and get back any opened device.
*/
r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_CTR,
ctr_str, str_size,
devices_rdata, &devices_rdata_size);
if (r < 0) {
if (r == -ESRCH)
DMERR("Userspace log server not found");
else
DMERR("Userspace log server failed to create log");
goto out;
}
/* Since the region size does not change, get it now */
rdata_size = sizeof(rdata);
r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_GET_REGION_SIZE,
NULL, 0, (char *)&rdata, &rdata_size);
if (r) {
DMERR("Failed to get region size of dirty log");
goto out;
}
lc->region_size = (uint32_t)rdata;
lc->region_count = dm_sector_div_up(ti->len, lc->region_size);
if (devices_rdata_size) {
if (devices_rdata[devices_rdata_size - 1] != '\0') {
DMERR("DM_ULOG_CTR device return string not properly terminated");
r = -EINVAL;
goto out;
}
r = dm_get_device(ti, devices_rdata,
dm_table_get_mode(ti->table), &lc->log_dev);
if (r)
DMERR("Failed to register %s with device-mapper",
devices_rdata);
}
if (lc->integrated_flush) {
lc->dmlog_wq = alloc_workqueue("dmlogd", WQ_MEM_RECLAIM, 0);
if (!lc->dmlog_wq) {
DMERR("couldn't start dmlogd");
r = -ENOMEM;
goto out;
}
INIT_DELAYED_WORK(&lc->flush_log_work, do_flush);
atomic_set(&lc->sched_flush, 0);
}
out:
kfree(devices_rdata);
if (r) {
if (lc->flush_entry_pool)
mempool_destroy(lc->flush_entry_pool);
kfree(lc);
kfree(ctr_str);
} else {
lc->usr_argv_str = ctr_str;
log->context = lc;
}
return r;
}
/*
* userspace_ctr
*
* argv contains:
* <UUID> <other args>
* Where 'other args' is the userspace implementation specific log
* arguments. An example might be:
* <UUID> clustered_disk <arg count> <log dev> <region_size> [[no]sync]
*
* So, this module will strip off the <UUID> for identification purposes
* when communicating with userspace about a log; but will pass on everything
* else.
*/
static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
unsigned argc, char **argv)
{
int r = 0;
int str_size;
char *ctr_str = NULL;
struct log_c *lc = NULL;
uint64_t rdata;
size_t rdata_size = sizeof(rdata);
if (argc < 3) {
DMWARN("Too few arguments to userspace dirty log");
return -EINVAL;
}
lc = kmalloc(sizeof(*lc), GFP_KERNEL);
if (!lc) {
DMWARN("Unable to allocate userspace log context.");
return -ENOMEM;
}
/* The ptr value is sufficient for local unique id */
lc->luid = (unsigned long)lc;
lc->ti = ti;
if (strlen(argv[0]) > (DM_UUID_LEN - 1)) {
DMWARN("UUID argument too long.");
kfree(lc);
return -EINVAL;
}
strncpy(lc->uuid, argv[0], DM_UUID_LEN);
spin_lock_init(&lc->flush_lock);
INIT_LIST_HEAD(&lc->mark_list);
INIT_LIST_HEAD(&lc->clear_list);
str_size = build_constructor_string(ti, argc - 1, argv + 1, &ctr_str);
if (str_size < 0) {
kfree(lc);
return str_size;
}
/* Send table string */
r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_CTR,
ctr_str, str_size, NULL, NULL);
if (r < 0) {
if (r == -ESRCH)
DMERR("Userspace log server not found");
else
DMERR("Userspace log server failed to create log");
goto out;
}
/* Since the region size does not change, get it now */
rdata_size = sizeof(rdata);
r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_GET_REGION_SIZE,
NULL, 0, (char *)&rdata, &rdata_size);
if (r) {
DMERR("Failed to get region size of dirty log");
goto out;
}
lc->region_size = (uint32_t)rdata;
lc->region_count = dm_sector_div_up(ti->len, lc->region_size);
out:
if (r) {
kfree(lc);
kfree(ctr_str);
} else {
lc->usr_argv_str = ctr_str;
lc->usr_argc = argc;
log->context = lc;
}
return r;
}