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Diffstat (limited to 'drivers/block/rnbd/rnbd-srv.c')
-rw-r--r--drivers/block/rnbd/rnbd-srv.c848
1 files changed, 848 insertions, 0 deletions
diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
new file mode 100644
index 000000000..2cfed2e58
--- /dev/null
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -0,0 +1,848 @@
+// 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);