linux-stable/drivers/md/dm-log-userspace-base.c
Tushar Sugandhi 8ec456629d dm: update target status functions to support IMA measurement
For device mapper targets to take advantage of IMA's measurement
capabilities, the status functions for the individual targets need to be
updated to handle the status_type_t case for value STATUSTYPE_IMA.

Update status functions for the following target types, to log their
respective attributes to be measured using IMA.
 01. cache
 02. crypt
 03. integrity
 04. linear
 05. mirror
 06. multipath
 07. raid
 08. snapshot
 09. striped
 10. verity

For rest of the targets, handle the STATUSTYPE_IMA case by setting the
measurement buffer to NULL.

For IMA to measure the data on a given system, the IMA policy on the
system needs to be updated to have the following line, and the system
needs to be restarted for the measurements to take effect.

/etc/ima/ima-policy
 measure func=CRITICAL_DATA label=device-mapper template=ima-buf

The measurements will be reflected in the IMA logs, which are located at:

/sys/kernel/security/integrity/ima/ascii_runtime_measurements
/sys/kernel/security/integrity/ima/binary_runtime_measurements

These IMA logs can later be consumed by various attestation clients
running on the system, and send them to external services for attesting
the system.

The DM target data measured by IMA subsystem can alternatively
be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
DM_TABLE_STATUS_CMD.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-10 13:34:23 -04:00

937 lines
22 KiB
C

/*
* Copyright (C) 2006-2009 Red Hat, Inc.
*
* This file is released under the LGPL.
*/
#include <linux/bio.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/dm-dirty-log.h>
#include <linux/device-mapper.h>
#include <linux/dm-log-userspace.h>
#include <linux/module.h>
#include <linux/workqueue.h>
#include "dm-log-userspace-transfer.h"
#define DM_LOG_USERSPACE_VSN "1.3.0"
#define FLUSH_ENTRY_POOL_SIZE 16
struct dm_dirty_log_flush_entry {
int type;
region_t region;
struct list_head list;
};
/*
* This limit on the number of mark and clear request is, to a degree,
* arbitrary. However, there is some basis for the choice in the limits
* imposed on the size of data payload by dm-log-userspace-transfer.c:
* dm_consult_userspace().
*/
#define MAX_FLUSH_GROUP_COUNT 32
struct log_c {
struct dm_target *ti;
struct dm_dev *log_dev;
char *usr_argv_str;
uint32_t usr_argc;
uint32_t region_size;
region_t region_count;
uint64_t luid;
char uuid[DM_UUID_LEN];
/*
* Mark and clear requests are held until a flush is issued
* so that we can group, and thereby limit, the amount of
* network traffic between kernel and userspace. The 'flush_lock'
* is used to protect these lists.
*/
spinlock_t flush_lock;
struct list_head mark_list;
struct list_head clear_list;
/*
* in_sync_hint gets set when doing is_remote_recovering. It
* represents the first region that needs recovery. IOW, the
* first zero bit of sync_bits. This can be useful for to limit
* traffic for calls like is_remote_recovering and get_resync_work,
* but be take care in its use for anything else.
*/
uint64_t in_sync_hint;
/*
* Workqueue for flush of clear region requests.
*/
struct workqueue_struct *dmlog_wq;
struct delayed_work flush_log_work;
atomic_t sched_flush;
/*
* Combine userspace flush and mark requests for efficiency.
*/
uint32_t integrated_flush;
mempool_t flush_entry_pool;
};
static struct kmem_cache *_flush_entry_cache;
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 int build_constructor_string(struct dm_target *ti,
unsigned argc, char **argv,
char **ctr_str)
{
int i, str_size;
char *str = NULL;
*ctr_str = NULL;
/*
* Determine overall size of the string.
*/
for (i = 0, str_size = 0; i < argc; i++)
str_size += strlen(argv[i]) + 1; /* +1 for space between args */
str_size += 20; /* Max number of chars in a printed u64 number */
str = kzalloc(str_size, GFP_KERNEL);
if (!str) {
DMWARN("Unable to allocate memory for constructor string");
return -ENOMEM;
}
str_size = sprintf(str, "%llu", (unsigned long long)ti->len);
for (i = 0; i < argc; i++)
str_size += sprintf(str + str_size, " %s", argv[i]);
*ctr_str = str;
return str_size;
}
static void do_flush(struct work_struct *work)
{
int r;
struct log_c *lc = container_of(work, struct log_c, flush_log_work.work);
atomic_set(&lc->sched_flush, 0);
r = userspace_do_request(lc, lc->uuid, DM_ULOG_FLUSH, NULL, 0, NULL, NULL);
if (r)
dm_table_event(lc->ti->table);
}
/*
* 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;
}
r = mempool_init_slab_pool(&lc->flush_entry_pool, FLUSH_ENTRY_POOL_SIZE,
_flush_entry_cache);
if (r) {
DMERR("Failed to create flush_entry_pool");
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) {
mempool_exit(&lc->flush_entry_pool);
kfree(lc);
kfree(ctr_str);
} else {
lc->usr_argv_str = ctr_str;
log->context = lc;
}
return r;
}
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_exit(&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_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;
}
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 uint32_t userspace_get_region_size(struct dm_dirty_log *log)
{
struct log_c *lc = log->context;
return lc->region_size;
}
/*
* userspace_is_clean
*
* Check whether a region is clean. If there is any sort of
* failure when consulting the server, we return not clean.
*
* Returns: 1 if clean, 0 otherwise
*/
static int userspace_is_clean(struct dm_dirty_log *log, region_t region)
{
int r;
uint64_t region64 = (uint64_t)region;
int64_t is_clean;
size_t rdata_size;
struct log_c *lc = log->context;
rdata_size = sizeof(is_clean);
r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_CLEAN,
(char *)&region64, sizeof(region64),
(char *)&is_clean, &rdata_size);
return (r) ? 0 : (int)is_clean;
}
/*
* userspace_in_sync
*
* Check if the region is in-sync. If there is any sort
* of failure when consulting the server, we assume that
* the region is not in sync.
*
* If 'can_block' is set, return immediately
*
* Returns: 1 if in-sync, 0 if not-in-sync, -EWOULDBLOCK
*/
static int userspace_in_sync(struct dm_dirty_log *log, region_t region,
int can_block)
{
int r;
uint64_t region64 = region;
int64_t in_sync;
size_t rdata_size;
struct log_c *lc = log->context;
/*
* We can never respond directly - even if in_sync_hint is
* set. This is because another machine could see a device
* failure and mark the region out-of-sync. If we don't go
* to userspace to ask, we might think the region is in-sync
* and allow a read to pick up data that is stale. (This is
* very unlikely if a device actually fails; but it is very
* likely if a connection to one device from one machine fails.)
*
* There still might be a problem if the mirror caches the region
* state as in-sync... but then this call would not be made. So,
* that is a mirror problem.
*/
if (!can_block)
return -EWOULDBLOCK;
rdata_size = sizeof(in_sync);
r = userspace_do_request(lc, lc->uuid, DM_ULOG_IN_SYNC,
(char *)&region64, sizeof(region64),
(char *)&in_sync, &rdata_size);
return (r) ? 0 : (int)in_sync;
}
static int flush_one_by_one(struct log_c *lc, struct list_head *flush_list)
{
int r = 0;
struct dm_dirty_log_flush_entry *fe;
list_for_each_entry(fe, flush_list, list) {
r = userspace_do_request(lc, lc->uuid, fe->type,
(char *)&fe->region,
sizeof(fe->region),
NULL, NULL);
if (r)
break;
}
return r;
}
static int flush_by_group(struct log_c *lc, struct list_head *flush_list,
int flush_with_payload)
{
int r = 0;
int count;
uint32_t type = 0;
struct dm_dirty_log_flush_entry *fe, *tmp_fe;
LIST_HEAD(tmp_list);
uint64_t group[MAX_FLUSH_GROUP_COUNT];
/*
* Group process the requests
*/
while (!list_empty(flush_list)) {
count = 0;
list_for_each_entry_safe(fe, tmp_fe, flush_list, list) {
group[count] = fe->region;
count++;
list_move(&fe->list, &tmp_list);
type = fe->type;
if (count >= MAX_FLUSH_GROUP_COUNT)
break;
}
if (flush_with_payload) {
r = userspace_do_request(lc, lc->uuid, DM_ULOG_FLUSH,
(char *)(group),
count * sizeof(uint64_t),
NULL, NULL);
/*
* Integrated flush failed.
*/
if (r)
break;
} else {
r = userspace_do_request(lc, lc->uuid, type,
(char *)(group),
count * sizeof(uint64_t),
NULL, NULL);
if (r) {
/*
* Group send failed. Attempt one-by-one.
*/
list_splice_init(&tmp_list, flush_list);
r = flush_one_by_one(lc, flush_list);
break;
}
}
}
/*
* Must collect flush_entrys that were successfully processed
* as a group so that they will be free'd by the caller.
*/
list_splice_init(&tmp_list, flush_list);
return r;
}
/*
* userspace_flush
*
* This function is ok to block.
* The flush happens in two stages. First, it sends all
* clear/mark requests that are on the list. Then it
* tells the server to commit them. This gives the
* server a chance to optimise the commit, instead of
* doing it for every request.
*
* Additionally, we could implement another thread that
* sends the requests up to the server - reducing the
* load on flush. Then the flush would have less in
* the list and be responsible for the finishing commit.
*
* Returns: 0 on success, < 0 on failure
*/
static int userspace_flush(struct dm_dirty_log *log)
{
int r = 0;
unsigned long flags;
struct log_c *lc = log->context;
LIST_HEAD(mark_list);
LIST_HEAD(clear_list);
int mark_list_is_empty;
int clear_list_is_empty;
struct dm_dirty_log_flush_entry *fe, *tmp_fe;
mempool_t *flush_entry_pool = &lc->flush_entry_pool;
spin_lock_irqsave(&lc->flush_lock, flags);
list_splice_init(&lc->mark_list, &mark_list);
list_splice_init(&lc->clear_list, &clear_list);
spin_unlock_irqrestore(&lc->flush_lock, flags);
mark_list_is_empty = list_empty(&mark_list);
clear_list_is_empty = list_empty(&clear_list);
if (mark_list_is_empty && clear_list_is_empty)
return 0;
r = flush_by_group(lc, &clear_list, 0);
if (r)
goto out;
if (!lc->integrated_flush) {
r = flush_by_group(lc, &mark_list, 0);
if (r)
goto out;
r = userspace_do_request(lc, lc->uuid, DM_ULOG_FLUSH,
NULL, 0, NULL, NULL);
goto out;
}
/*
* Send integrated flush request with mark_list as payload.
*/
r = flush_by_group(lc, &mark_list, 1);
if (r)
goto out;
if (mark_list_is_empty && !atomic_read(&lc->sched_flush)) {
/*
* When there are only clear region requests,
* we schedule a flush in the future.
*/
queue_delayed_work(lc->dmlog_wq, &lc->flush_log_work, 3 * HZ);
atomic_set(&lc->sched_flush, 1);
} else {
/*
* Cancel pending flush because we
* have already flushed in mark_region.
*/
cancel_delayed_work(&lc->flush_log_work);
atomic_set(&lc->sched_flush, 0);
}
out:
/*
* We can safely remove these entries, even after failure.
* Calling code will receive an error and will know that
* the log facility has failed.
*/
list_for_each_entry_safe(fe, tmp_fe, &mark_list, list) {
list_del(&fe->list);
mempool_free(fe, flush_entry_pool);
}
list_for_each_entry_safe(fe, tmp_fe, &clear_list, list) {
list_del(&fe->list);
mempool_free(fe, flush_entry_pool);
}
if (r)
dm_table_event(lc->ti->table);
return r;
}
/*
* userspace_mark_region
*
* This function should avoid blocking unless absolutely required.
* (Memory allocation is valid for blocking.)
*/
static void userspace_mark_region(struct dm_dirty_log *log, region_t region)
{
unsigned long flags;
struct log_c *lc = log->context;
struct dm_dirty_log_flush_entry *fe;
/* Wait for an allocation, but _never_ fail */
fe = mempool_alloc(&lc->flush_entry_pool, GFP_NOIO);
BUG_ON(!fe);
spin_lock_irqsave(&lc->flush_lock, flags);
fe->type = DM_ULOG_MARK_REGION;
fe->region = region;
list_add(&fe->list, &lc->mark_list);
spin_unlock_irqrestore(&lc->flush_lock, flags);
return;
}
/*
* userspace_clear_region
*
* This function must not block.
* So, the alloc can't block. In the worst case, it is ok to
* fail. It would simply mean we can't clear the region.
* Does nothing to current sync context, but does mean
* the region will be re-sync'ed on a reload of the mirror
* even though it is in-sync.
*/
static void userspace_clear_region(struct dm_dirty_log *log, region_t region)
{
unsigned long flags;
struct log_c *lc = log->context;
struct dm_dirty_log_flush_entry *fe;
/*
* If we fail to allocate, we skip the clearing of
* the region. This doesn't hurt us in any way, except
* to cause the region to be resync'ed when the
* device is activated next time.
*/
fe = mempool_alloc(&lc->flush_entry_pool, GFP_ATOMIC);
if (!fe) {
DMERR("Failed to allocate memory to clear region.");
return;
}
spin_lock_irqsave(&lc->flush_lock, flags);
fe->type = DM_ULOG_CLEAR_REGION;
fe->region = region;
list_add(&fe->list, &lc->clear_list);
spin_unlock_irqrestore(&lc->flush_lock, flags);
return;
}
/*
* userspace_get_resync_work
*
* Get a region that needs recovery. It is valid to return
* an error for this function.
*
* Returns: 1 if region filled, 0 if no work, <0 on error
*/
static int userspace_get_resync_work(struct dm_dirty_log *log, region_t *region)
{
int r;
size_t rdata_size;
struct log_c *lc = log->context;
struct {
int64_t i; /* 64-bit for mix arch compatibility */
region_t r;
} pkg;
if (lc->in_sync_hint >= lc->region_count)
return 0;
rdata_size = sizeof(pkg);
r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_RESYNC_WORK,
NULL, 0, (char *)&pkg, &rdata_size);
*region = pkg.r;
return (r) ? r : (int)pkg.i;
}
/*
* userspace_set_region_sync
*
* Set the sync status of a given region. This function
* must not fail.
*/
static void userspace_set_region_sync(struct dm_dirty_log *log,
region_t region, int in_sync)
{
struct log_c *lc = log->context;
struct {
region_t r;
int64_t i;
} pkg;
pkg.r = region;
pkg.i = (int64_t)in_sync;
(void) userspace_do_request(lc, lc->uuid, DM_ULOG_SET_REGION_SYNC,
(char *)&pkg, sizeof(pkg), NULL, NULL);
/*
* It would be nice to be able to report failures.
* However, it is easy enough to detect and resolve.
*/
return;
}
/*
* userspace_get_sync_count
*
* If there is any sort of failure when consulting the server,
* we assume that the sync count is zero.
*
* Returns: sync count on success, 0 on failure
*/
static region_t userspace_get_sync_count(struct dm_dirty_log *log)
{
int r;
size_t rdata_size;
uint64_t sync_count;
struct log_c *lc = log->context;
rdata_size = sizeof(sync_count);
r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_SYNC_COUNT,
NULL, 0, (char *)&sync_count, &rdata_size);
if (r)
return 0;
if (sync_count >= lc->region_count)
lc->in_sync_hint = lc->region_count;
return (region_t)sync_count;
}
/*
* userspace_status
*
* Returns: amount of space consumed
*/
static int userspace_status(struct dm_dirty_log *log, status_type_t status_type,
char *result, unsigned maxlen)
{
int r = 0;
char *table_args;
size_t sz = (size_t)maxlen;
struct log_c *lc = log->context;
switch (status_type) {
case STATUSTYPE_INFO:
r = userspace_do_request(lc, lc->uuid, DM_ULOG_STATUS_INFO,
NULL, 0, result, &sz);
if (r) {
sz = 0;
DMEMIT("%s 1 COM_FAILURE", log->type->name);
}
break;
case STATUSTYPE_TABLE:
sz = 0;
table_args = strchr(lc->usr_argv_str, ' ');
BUG_ON(!table_args); /* There will always be a ' ' */
table_args++;
DMEMIT("%s %u %s ", log->type->name, lc->usr_argc, lc->uuid);
if (lc->integrated_flush)
DMEMIT("integrated_flush ");
DMEMIT("%s ", table_args);
break;
case STATUSTYPE_IMA:
*result = '\0';
break;
}
return (r) ? 0 : (int)sz;
}
/*
* userspace_is_remote_recovering
*
* Returns: 1 if region recovering, 0 otherwise
*/
static int userspace_is_remote_recovering(struct dm_dirty_log *log,
region_t region)
{
int r;
uint64_t region64 = region;
struct log_c *lc = log->context;
static unsigned long limit;
struct {
int64_t is_recovering;
uint64_t in_sync_hint;
} pkg;
size_t rdata_size = sizeof(pkg);
/*
* Once the mirror has been reported to be in-sync,
* it will never again ask for recovery work. So,
* we can safely say there is not a remote machine
* recovering if the device is in-sync. (in_sync_hint
* must be reset at resume time.)
*/
if (region < lc->in_sync_hint)
return 0;
else if (time_after(limit, jiffies))
return 1;
limit = jiffies + (HZ / 4);
r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_REMOTE_RECOVERING,
(char *)&region64, sizeof(region64),
(char *)&pkg, &rdata_size);
if (r)
return 1;
lc->in_sync_hint = pkg.in_sync_hint;
return (int)pkg.is_recovering;
}
static struct dm_dirty_log_type _userspace_type = {
.name = "userspace",
.module = THIS_MODULE,
.ctr = userspace_ctr,
.dtr = userspace_dtr,
.presuspend = userspace_presuspend,
.postsuspend = userspace_postsuspend,
.resume = userspace_resume,
.get_region_size = userspace_get_region_size,
.is_clean = userspace_is_clean,
.in_sync = userspace_in_sync,
.flush = userspace_flush,
.mark_region = userspace_mark_region,
.clear_region = userspace_clear_region,
.get_resync_work = userspace_get_resync_work,
.set_region_sync = userspace_set_region_sync,
.get_sync_count = userspace_get_sync_count,
.status = userspace_status,
.is_remote_recovering = userspace_is_remote_recovering,
};
static int __init userspace_dirty_log_init(void)
{
int r = 0;
_flush_entry_cache = KMEM_CACHE(dm_dirty_log_flush_entry, 0);
if (!_flush_entry_cache) {
DMWARN("Unable to create flush_entry_cache: No memory.");
return -ENOMEM;
}
r = dm_ulog_tfr_init();
if (r) {
DMWARN("Unable to initialize userspace log communications");
kmem_cache_destroy(_flush_entry_cache);
return r;
}
r = dm_dirty_log_type_register(&_userspace_type);
if (r) {
DMWARN("Couldn't register userspace dirty log type");
dm_ulog_tfr_exit();
kmem_cache_destroy(_flush_entry_cache);
return r;
}
DMINFO("version " DM_LOG_USERSPACE_VSN " loaded");
return 0;
}
static void __exit userspace_dirty_log_exit(void)
{
dm_dirty_log_type_unregister(&_userspace_type);
dm_ulog_tfr_exit();
kmem_cache_destroy(_flush_entry_cache);
DMINFO("version " DM_LOG_USERSPACE_VSN " unloaded");
return;
}
module_init(userspace_dirty_log_init);
module_exit(userspace_dirty_log_exit);
MODULE_DESCRIPTION(DM_NAME " userspace dirty log link");
MODULE_AUTHOR("Jonathan Brassow <dm-devel@redhat.com>");
MODULE_LICENSE("GPL");