blob: 2cfed2e58d646f5df11fc4baa6125e1f0527d0e7 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* RDMA Network Block Driver
*
* Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
* Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
* Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
*/
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
#include <linux/module.h>
#include <linux/blkdev.h>
#include "rnbd-srv.h"
#include "rnbd-srv-trace.h"
MODULE_DESCRIPTION("RDMA Network Block Device Server");
MODULE_LICENSE("GPL");
static u16 port_nr = RTRS_PORT;
module_param_named(port_nr, port_nr, ushort, 0444);
MODULE_PARM_DESC(port_nr,
"The port number the server is listening on (default: "
__stringify(RTRS_PORT)")");
#define DEFAULT_DEV_SEARCH_PATH "/"
static char dev_search_path[PATH_MAX] = DEFAULT_DEV_SEARCH_PATH;
static int dev_search_path_set(const char *val, const struct kernel_param *kp)
{
const char *p = strrchr(val, '\n') ? : val + strlen(val);
if (strlen(val) >= sizeof(dev_search_path))
return -EINVAL;
snprintf(dev_search_path, sizeof(dev_search_path), "%.*s",
(int)(p - val), val);
pr_info("dev_search_path changed to '%s'\n", dev_search_path);
return 0;
}
static struct kparam_string dev_search_path_kparam_str = {
.maxlen = sizeof(dev_search_path),
.string = dev_search_path
};
static const struct kernel_param_ops dev_search_path_ops = {
.set = dev_search_path_set,
.get = param_get_string,
};
module_param_cb(dev_search_path, &dev_search_path_ops,
&dev_search_path_kparam_str, 0444);
MODULE_PARM_DESC(dev_search_path,
"Sets the dev_search_path. When a device is mapped this path is prepended to the device path from the map device operation. If %SESSNAME% is specified in a path, then device will be searched in a session namespace. (default: "
DEFAULT_DEV_SEARCH_PATH ")");
static DEFINE_MUTEX(sess_lock);
static DEFINE_SPINLOCK(dev_lock);
static LIST_HEAD(sess_list);
static LIST_HEAD(dev_list);
struct rnbd_io_private {
struct rtrs_srv_op *id;
struct rnbd_srv_sess_dev *sess_dev;
};
static void rnbd_sess_dev_release(struct kref *kref)
{
struct rnbd_srv_sess_dev *sess_dev;
sess_dev = container_of(kref, struct rnbd_srv_sess_dev, kref);
complete(sess_dev->destroy_comp);
}
static inline void rnbd_put_sess_dev(struct rnbd_srv_sess_dev *sess_dev)
{
kref_put(&sess_dev->kref, rnbd_sess_dev_release);
}
static struct rnbd_srv_sess_dev *
rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess)
{
struct rnbd_srv_sess_dev *sess_dev;
int ret = 0;
rcu_read_lock();
sess_dev = xa_load(&srv_sess->index_idr, dev_id);
if (sess_dev)
ret = kref_get_unless_zero(&sess_dev->kref);
rcu_read_unlock();
if (!sess_dev || !ret)
return ERR_PTR(-ENXIO);
return sess_dev;
}
static void rnbd_dev_bi_end_io(struct bio *bio)
{
struct rnbd_io_private *rnbd_priv = bio->bi_private;
struct rnbd_srv_sess_dev *sess_dev = rnbd_priv->sess_dev;
rnbd_put_sess_dev(sess_dev);
rtrs_srv_resp_rdma(rnbd_priv->id, blk_status_to_errno(bio->bi_status));
kfree(rnbd_priv);
bio_put(bio);
}
static int process_rdma(struct rnbd_srv_session *srv_sess,
struct rtrs_srv_op *id, void *data, u32 datalen,
const void *usr, size_t usrlen)
{
const struct rnbd_msg_io *msg = usr;
struct rnbd_io_private *priv;
struct rnbd_srv_sess_dev *sess_dev;
u32 dev_id;
int err;
struct bio *bio;
short prio;
trace_process_rdma(srv_sess, msg, id, datalen, usrlen);
priv = kmalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
dev_id = le32_to_cpu(msg->device_id);
sess_dev = rnbd_get_sess_dev(dev_id, srv_sess);
if (IS_ERR(sess_dev)) {
pr_err_ratelimited("Got I/O request on session %s for unknown device id %d\n",
srv_sess->sessname, dev_id);
err = -ENOTCONN;
goto err;
}
priv->sess_dev = sess_dev;
priv->id = id;
bio = bio_alloc(sess_dev->bdev, 1,
rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL);
if (bio_add_page(bio, virt_to_page(data), datalen,
offset_in_page(data)) != datalen) {
rnbd_srv_err(sess_dev, "Failed to map data to bio\n");
err = -EINVAL;
goto bio_put;
}
bio->bi_end_io = rnbd_dev_bi_end_io;
bio->bi_private = priv;
bio->bi_iter.bi_sector = le64_to_cpu(msg->sector);
bio->bi_iter.bi_size = le32_to_cpu(msg->bi_size);
prio = srv_sess->ver < RNBD_PROTO_VER_MAJOR ||
usrlen < sizeof(*msg) ? 0 : le16_to_cpu(msg->prio);
bio_set_prio(bio, prio);
submit_bio(bio);
return 0;
bio_put:
bio_put(bio);
rnbd_put_sess_dev(sess_dev);
err:
kfree(priv);
return err;
}
static void destroy_device(struct kref *kref)
{
struct rnbd_srv_dev *dev = container_of(kref, struct rnbd_srv_dev, kref);
WARN_ONCE(!list_empty(&dev->sess_dev_list),
"Device %s is being destroyed but still in use!\n",
dev->id);
spin_lock(&dev_lock);
list_del(&dev->list);
spin_unlock(&dev_lock);
mutex_destroy(&dev->lock);
if (dev->dev_kobj.state_in_sysfs)
/*
* Destroy kobj only if it was really created.
*/
rnbd_srv_destroy_dev_sysfs(dev);
else
kfree(dev);
}
static void rnbd_put_srv_dev(struct rnbd_srv_dev *dev)
{
kref_put(&dev->kref, destroy_device);
}
void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id)
{
DECLARE_COMPLETION_ONSTACK(dc);
if (keep_id)
/* free the resources for the id but don't */
/* allow to re-use the id itself because it */
/* is still used by the client */
xa_cmpxchg(&sess_dev->sess->index_idr, sess_dev->device_id,
sess_dev, NULL, 0);
else
xa_erase(&sess_dev->sess->index_idr, sess_dev->device_id);
synchronize_rcu();
sess_dev->destroy_comp = &dc;
rnbd_put_sess_dev(sess_dev);
wait_for_completion(&dc); /* wait for inflights to drop to zero */
blkdev_put(sess_dev->bdev, sess_dev->open_flags);
mutex_lock(&sess_dev->dev->lock);
list_del(&sess_dev->dev_list);
if (sess_dev->open_flags & FMODE_WRITE)
sess_dev->dev->open_write_cnt--;
mutex_unlock(&sess_dev->dev->lock);
rnbd_put_srv_dev(sess_dev->dev);
rnbd_srv_info(sess_dev, "Device closed\n");
kfree(sess_dev);
}
static void destroy_sess(struct rnbd_srv_session *srv_sess)
{
struct rnbd_srv_sess_dev *sess_dev;
unsigned long index;
if (xa_empty(&srv_sess->index_idr))
goto out;
trace_destroy_sess(srv_sess);
mutex_lock(&srv_sess->lock);
xa_for_each(&srv_sess->index_idr, index, sess_dev)
rnbd_srv_destroy_dev_session_sysfs(sess_dev);
mutex_unlock(&srv_sess->lock);
out:
xa_destroy(&srv_sess->index_idr);
pr_info("RTRS Session %s disconnected\n", srv_sess->sessname);
mutex_lock(&sess_lock);
list_del(&srv_sess->list);
mutex_unlock(&sess_lock);
mutex_destroy(&srv_sess->lock);
kfree(srv_sess);
}
static int create_sess(struct rtrs_srv_sess *rtrs)
{
struct rnbd_srv_session *srv_sess;
char pathname[NAME_MAX];
int err;
err = rtrs_srv_get_path_name(rtrs, pathname, sizeof(pathname));
if (err) {
pr_err("rtrs_srv_get_path_name(%s): %d\n", pathname, err);
return err;
}
srv_sess = kzalloc(sizeof(*srv_sess), GFP_KERNEL);
if (!srv_sess)
return -ENOMEM;
srv_sess->queue_depth = rtrs_srv_get_queue_depth(rtrs);
xa_init_flags(&srv_sess->index_idr, XA_FLAGS_ALLOC);
mutex_init(&srv_sess->lock);
mutex_lock(&sess_lock);
list_add(&srv_sess->list, &sess_list);
mutex_unlock(&sess_lock);
srv_sess->rtrs = rtrs;
strscpy(srv_sess->sessname, pathname, sizeof(srv_sess->sessname));
rtrs_srv_set_sess_priv(rtrs, srv_sess);
trace_create_sess(srv_sess);
return 0;
}
static int rnbd_srv_link_ev(struct rtrs_srv_sess *rtrs,
enum rtrs_srv_link_ev ev, void *priv)
{
struct rnbd_srv_session *srv_sess = priv;
switch (ev) {
case RTRS_SRV_LINK_EV_CONNECTED:
return create_sess(rtrs);
case RTRS_SRV_LINK_EV_DISCONNECTED:
if (WARN_ON_ONCE(!srv_sess))
return -EINVAL;
destroy_sess(srv_sess);
return 0;
default:
pr_warn("Received unknown RTRS session event %d from session %s\n",
ev, srv_sess->sessname);
return -EINVAL;
}
}
void rnbd_srv_sess_dev_force_close(struct rnbd_srv_sess_dev *sess_dev,
struct kobj_attribute *attr)
{
struct rnbd_srv_session *sess = sess_dev->sess;
/* It is already started to close by client's close message. */
if (!mutex_trylock(&sess->lock))
return;
sess_dev->keep_id = true;
/* first remove sysfs itself to avoid deadlock */
sysfs_remove_file_self(&sess_dev->kobj, &attr->attr);
rnbd_srv_destroy_dev_session_sysfs(sess_dev);
mutex_unlock(&sess->lock);
}
static void process_msg_close(struct rnbd_srv_session *srv_sess,
void *data, size_t datalen, const void *usr,
size_t usrlen)
{
const struct rnbd_msg_close *close_msg = usr;
struct rnbd_srv_sess_dev *sess_dev;
trace_process_msg_close(srv_sess, close_msg);
sess_dev = rnbd_get_sess_dev(le32_to_cpu(close_msg->device_id),
srv_sess);
if (IS_ERR(sess_dev))
return;
rnbd_put_sess_dev(sess_dev);
mutex_lock(&srv_sess->lock);
rnbd_srv_destroy_dev_session_sysfs(sess_dev);
mutex_unlock(&srv_sess->lock);
}
static int process_msg_open(struct rnbd_srv_session *srv_sess,
const void *msg, size_t len,
void *data, size_t datalen);
static int process_msg_sess_info(struct rnbd_srv_session *srv_sess,
const void *msg, size_t len,
void *data, size_t datalen);
static int rnbd_srv_rdma_ev(void *priv, struct rtrs_srv_op *id,
void *data, size_t datalen,
const void *usr, size_t usrlen)
{
struct rnbd_srv_session *srv_sess = priv;
const struct rnbd_msg_hdr *hdr = usr;
int ret = 0;
u16 type;
if (WARN_ON_ONCE(!srv_sess))
return -ENODEV;
type = le16_to_cpu(hdr->type);
switch (type) {
case RNBD_MSG_IO:
return process_rdma(srv_sess, id, data, datalen, usr, usrlen);
case RNBD_MSG_CLOSE:
process_msg_close(srv_sess, data, datalen, usr, usrlen);
break;
case RNBD_MSG_OPEN:
ret = process_msg_open(srv_sess, usr, usrlen, data, datalen);
break;
case RNBD_MSG_SESS_INFO:
ret = process_msg_sess_info(srv_sess, usr, usrlen, data,
datalen);
break;
default:
pr_warn("Received unexpected message type %d from session %s\n",
type, srv_sess->sessname);
return -EINVAL;
}
/*
* Since ret is passed to rtrs to handle the failure case, we
* just return 0 at the end otherwise callers in rtrs would call
* send_io_resp_imm again to print redundant err message.
*/
rtrs_srv_resp_rdma(id, ret);
return 0;
}
static struct rnbd_srv_sess_dev
*rnbd_sess_dev_alloc(struct rnbd_srv_session *srv_sess)
{
struct rnbd_srv_sess_dev *sess_dev;
int error;
sess_dev = kzalloc(sizeof(*sess_dev), GFP_KERNEL);
if (!sess_dev)
return ERR_PTR(-ENOMEM);
error = xa_alloc(&srv_sess->index_idr, &sess_dev->device_id, sess_dev,
xa_limit_32b, GFP_NOWAIT);
if (error < 0) {
pr_warn("Allocating idr failed, err: %d\n", error);
kfree(sess_dev);
return ERR_PTR(error);
}
return sess_dev;
}
static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev)
{
struct rnbd_srv_dev *dev;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return ERR_PTR(-ENOMEM);
snprintf(dev->id, sizeof(dev->id), "%pg", bdev);
kref_init(&dev->kref);
INIT_LIST_HEAD(&dev->sess_dev_list);
mutex_init(&dev->lock);
return dev;
}
static struct rnbd_srv_dev *
rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev)
{
struct rnbd_srv_dev *dev;
spin_lock(&dev_lock);
list_for_each_entry(dev, &dev_list, list) {
if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) {
if (!kref_get_unless_zero(&dev->kref))
/*
* We lost the race, device is almost dead.
* Continue traversing to find a valid one.
*/
continue;
spin_unlock(&dev_lock);
return dev;
}
}
list_add(&new_dev->list, &dev_list);
spin_unlock(&dev_lock);
return new_dev;
}
static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev,
struct rnbd_srv_session *srv_sess,
enum rnbd_access_mode access_mode)
{
int ret = -EPERM;
mutex_lock(&srv_dev->lock);
switch (access_mode) {
case RNBD_ACCESS_RO:
ret = 0;
break;
case RNBD_ACCESS_RW:
if (srv_dev->open_write_cnt == 0) {
srv_dev->open_write_cnt++;
ret = 0;
} else {
pr_err("Mapping device '%s' for session %s with RW permissions failed. Device already opened as 'RW' by %d client(s), access mode %s.\n",
srv_dev->id, srv_sess->sessname,
srv_dev->open_write_cnt,
rnbd_access_mode_str(access_mode));
}
break;
case RNBD_ACCESS_MIGRATION:
if (srv_dev->open_write_cnt < 2) {
srv_dev->open_write_cnt++;
ret = 0;
} else {
pr_err("Mapping device '%s' for session %s with migration permissions failed. Device already opened as 'RW' by %d client(s), access mode %s.\n",
srv_dev->id, srv_sess->sessname,
srv_dev->open_write_cnt,
rnbd_access_mode_str(access_mode));
}
break;
default:
pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n",
srv_dev->id, srv_sess->sessname, access_mode);
ret = -EINVAL;
}
mutex_unlock(&srv_dev->lock);
return ret;
}
static struct rnbd_srv_dev *
rnbd_srv_get_or_create_srv_dev(struct block_device *bdev,
struct rnbd_srv_session *srv_sess,
enum rnbd_access_mode access_mode)
{
int ret;
struct rnbd_srv_dev *new_dev, *dev;
new_dev = rnbd_srv_init_srv_dev(bdev);
if (IS_ERR(new_dev))
return new_dev;
dev = rnbd_srv_find_or_add_srv_dev(new_dev);
if (dev != new_dev)
kfree(new_dev);
ret = rnbd_srv_check_update_open_perm(dev, srv_sess, access_mode);
if (ret) {
rnbd_put_srv_dev(dev);
return ERR_PTR(ret);
}
return dev;
}
static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp,
struct rnbd_srv_sess_dev *sess_dev)
{
struct block_device *bdev = sess_dev->bdev;
rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP);
rsp->device_id = cpu_to_le32(sess_dev->device_id);
rsp->nsectors = cpu_to_le64(bdev_nr_sectors(bdev));
rsp->logical_block_size = cpu_to_le16(bdev_logical_block_size(bdev));
rsp->physical_block_size = cpu_to_le16(bdev_physical_block_size(bdev));
rsp->max_segments = cpu_to_le16(bdev_max_segments(bdev));
rsp->max_hw_sectors =
cpu_to_le32(queue_max_hw_sectors(bdev_get_queue(bdev)));
rsp->max_write_same_sectors = 0;
rsp->max_discard_sectors = cpu_to_le32(bdev_max_discard_sectors(bdev));
rsp->discard_granularity = cpu_to_le32(bdev_discard_granularity(bdev));
rsp->discard_alignment = cpu_to_le32(bdev_discard_alignment(bdev));
rsp->secure_discard = cpu_to_le16(bdev_max_secure_erase_sectors(bdev));
rsp->cache_policy = 0;
if (bdev_write_cache(bdev))
rsp->cache_policy |= RNBD_WRITEBACK;
if (bdev_fua(bdev))
rsp->cache_policy |= RNBD_FUA;
}
static struct rnbd_srv_sess_dev *
rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess,
const struct rnbd_msg_open *open_msg,
struct block_device *bdev, fmode_t open_flags,
struct rnbd_srv_dev *srv_dev)
{
struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess);
if (IS_ERR(sdev))
return sdev;
kref_init(&sdev->kref);
strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname));
sdev->bdev = bdev;
sdev->sess = srv_sess;
sdev->dev = srv_dev;
sdev->open_flags = open_flags;
sdev->access_mode = open_msg->access_mode;
return sdev;
}
static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess,
const char *dev_name)
{
char *full_path;
char *a, *b;
full_path = kmalloc(PATH_MAX, GFP_KERNEL);
if (!full_path)
return ERR_PTR(-ENOMEM);
/*
* Replace %SESSNAME% with a real session name in order to
* create device namespace.
*/
a = strnstr(dev_search_path, "%SESSNAME%", sizeof(dev_search_path));
if (a) {
int len = a - dev_search_path;
len = snprintf(full_path, PATH_MAX, "%.*s/%s/%s", len,
dev_search_path, srv_sess->sessname, dev_name);
if (len >= PATH_MAX) {
pr_err("Too long path: %s, %s, %s\n",
dev_search_path, srv_sess->sessname, dev_name);
kfree(full_path);
return ERR_PTR(-EINVAL);
}
} else {
snprintf(full_path, PATH_MAX, "%s/%s",
dev_search_path, dev_name);
}
/* eliminitate duplicated slashes */
a = strchr(full_path, '/');
b = a;
while (*b != '\0') {
if (*b == '/' && *a == '/') {
b++;
} else {
a++;
*a = *b;
b++;
}
}
a++;
*a = '\0';
return full_path;
}
static int process_msg_sess_info(struct rnbd_srv_session *srv_sess,
const void *msg, size_t len,
void *data, size_t datalen)
{
const struct rnbd_msg_sess_info *sess_info_msg = msg;
struct rnbd_msg_sess_info_rsp *rsp = data;
srv_sess->ver = min_t(u8, sess_info_msg->ver, RNBD_PROTO_VER_MAJOR);
trace_process_msg_sess_info(srv_sess, sess_info_msg);
rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP);
rsp->ver = srv_sess->ver;
return 0;
}
/**
* find_srv_sess_dev() - a dev is already opened by this name
* @srv_sess: the session to search.
* @dev_name: string containing the name of the device.
*
* Return struct rnbd_srv_sess_dev if srv_sess already opened the dev_name
* NULL if the session didn't open the device yet.
*/
static struct rnbd_srv_sess_dev *
find_srv_sess_dev(struct rnbd_srv_session *srv_sess, const char *dev_name)
{
struct rnbd_srv_sess_dev *sess_dev;
unsigned long index;
if (xa_empty(&srv_sess->index_idr))
return NULL;
xa_for_each(&srv_sess->index_idr, index, sess_dev)
if (!strcmp(sess_dev->pathname, dev_name))
return sess_dev;
return NULL;
}
static int process_msg_open(struct rnbd_srv_session *srv_sess,
const void *msg, size_t len,
void *data, size_t datalen)
{
int ret;
struct rnbd_srv_dev *srv_dev;
struct rnbd_srv_sess_dev *srv_sess_dev;
const struct rnbd_msg_open *open_msg = msg;
struct block_device *bdev;
fmode_t open_flags;
char *full_path;
struct rnbd_msg_open_rsp *rsp = data;
trace_process_msg_open(srv_sess, open_msg);
open_flags = FMODE_READ;
if (open_msg->access_mode != RNBD_ACCESS_RO)
open_flags |= FMODE_WRITE;
mutex_lock(&srv_sess->lock);
srv_sess_dev = find_srv_sess_dev(srv_sess, open_msg->dev_name);
if (srv_sess_dev)
goto fill_response;
if ((strlen(dev_search_path) + strlen(open_msg->dev_name))
>= PATH_MAX) {
pr_err("Opening device for session %s failed, device path too long. '%s/%s' is longer than PATH_MAX (%d)\n",
srv_sess->sessname, dev_search_path, open_msg->dev_name,
PATH_MAX);
ret = -EINVAL;
goto reject;
}
if (strstr(open_msg->dev_name, "..")) {
pr_err("Opening device for session %s failed, device path %s contains relative path ..\n",
srv_sess->sessname, open_msg->dev_name);
ret = -EINVAL;
goto reject;
}
full_path = rnbd_srv_get_full_path(srv_sess, open_msg->dev_name);
if (IS_ERR(full_path)) {
ret = PTR_ERR(full_path);
pr_err("Opening device '%s' for client %s failed, failed to get device full path, err: %d\n",
open_msg->dev_name, srv_sess->sessname, ret);
goto reject;
}
bdev = blkdev_get_by_path(full_path, open_flags, THIS_MODULE);
if (IS_ERR(bdev)) {
ret = PTR_ERR(bdev);
pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %d\n",
full_path, srv_sess->sessname, ret);
goto free_path;
}
srv_dev = rnbd_srv_get_or_create_srv_dev(bdev, srv_sess,
open_msg->access_mode);
if (IS_ERR(srv_dev)) {
pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n",
full_path, srv_sess->sessname, PTR_ERR(srv_dev));
ret = PTR_ERR(srv_dev);
goto blkdev_put;
}
srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg,
bdev, open_flags,
srv_dev);
if (IS_ERR(srv_sess_dev)) {
pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n",
full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev));
ret = PTR_ERR(srv_sess_dev);
goto srv_dev_put;
}
/* Create the srv_dev sysfs files if they haven't been created yet. The
* reason to delay the creation is not to create the sysfs files before
* we are sure the device can be opened.
*/
mutex_lock(&srv_dev->lock);
if (!srv_dev->dev_kobj.state_in_sysfs) {
ret = rnbd_srv_create_dev_sysfs(srv_dev, bdev);
if (ret) {
mutex_unlock(&srv_dev->lock);
rnbd_srv_err(srv_sess_dev,
"Opening device failed, failed to create device sysfs files, err: %d\n",
ret);
goto free_srv_sess_dev;
}
}
ret = rnbd_srv_create_dev_session_sysfs(srv_sess_dev);
if (ret) {
mutex_unlock(&srv_dev->lock);
rnbd_srv_err(srv_sess_dev,
"Opening device failed, failed to create dev client sysfs files, err: %d\n",
ret);
goto free_srv_sess_dev;
}
list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list);
mutex_unlock(&srv_dev->lock);
rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id);
kfree(full_path);
fill_response:
rnbd_srv_fill_msg_open_rsp(rsp, srv_sess_dev);
mutex_unlock(&srv_sess->lock);
return 0;
free_srv_sess_dev:
xa_erase(&srv_sess->index_idr, srv_sess_dev->device_id);
synchronize_rcu();
kfree(srv_sess_dev);
srv_dev_put:
if (open_msg->access_mode != RNBD_ACCESS_RO) {
mutex_lock(&srv_dev->lock);
srv_dev->open_write_cnt--;
mutex_unlock(&srv_dev->lock);
}
rnbd_put_srv_dev(srv_dev);
blkdev_put:
blkdev_put(bdev, open_flags);
free_path:
kfree(full_path);
reject:
mutex_unlock(&srv_sess->lock);
return ret;
}
static struct rtrs_srv_ctx *rtrs_ctx;
static struct rtrs_srv_ops rtrs_ops;
static int __init rnbd_srv_init_module(void)
{
int err;
BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4);
BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36);
BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info_rsp) != 36);
BUILD_BUG_ON(sizeof(struct rnbd_msg_open) != 264);
BUILD_BUG_ON(sizeof(struct rnbd_msg_close) != 8);
BUILD_BUG_ON(sizeof(struct rnbd_msg_open_rsp) != 56);
rtrs_ops = (struct rtrs_srv_ops) {
.rdma_ev = rnbd_srv_rdma_ev,
.link_ev = rnbd_srv_link_ev,
};
rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr);
if (IS_ERR(rtrs_ctx)) {
err = PTR_ERR(rtrs_ctx);
pr_err("rtrs_srv_open(), err: %d\n", err);
return err;
}
err = rnbd_srv_create_sysfs_files();
if (err) {
pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err);
rtrs_srv_close(rtrs_ctx);
return err;
}
return 0;
}
static void __exit rnbd_srv_cleanup_module(void)
{
rtrs_srv_close(rtrs_ctx);
WARN_ON(!list_empty(&sess_list));
rnbd_srv_destroy_sysfs_files();
}
module_init(rnbd_srv_init_module);
module_exit(rnbd_srv_cleanup_module);