blob: a87fca82a7963c56f3514256c0dda2f334bc6e7b [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-or-later */
* Copyright (C) 2017, Microsoft Corporation.
* Author(s): Long Li <>
#ifndef _SMBDIRECT_H
#define _SMBDIRECT_H
#define cifs_rdma_enabled(server) ((server)->rdma)
#include "cifsglob.h"
#include <rdma/ib_verbs.h>
#include <rdma/rdma_cm.h>
#include <linux/mempool.h>
extern int rdma_readwrite_threshold;
extern int smbd_max_frmr_depth;
extern int smbd_keep_alive_interval;
extern int smbd_max_receive_size;
extern int smbd_max_fragmented_recv_size;
extern int smbd_max_send_size;
extern int smbd_send_credit_target;
extern int smbd_receive_credit_max;
enum keep_alive_status {
enum smbd_connection_status {
* The context for the SMBDirect transport
* Everything related to the transport is here. It has several logical parts
* 1. RDMA related structures
* 2. SMBDirect connection parameters
* 3. Memory registrations
* 4. Receive and reassembly queues for data receive path
* 5. mempools for allocating packets
struct smbd_connection {
enum smbd_connection_status transport_status;
/* RDMA related */
struct rdma_cm_id *id;
struct ib_qp_init_attr qp_attr;
struct ib_pd *pd;
struct ib_cq *send_cq, *recv_cq;
struct ib_device_attr dev_attr;
int ri_rc;
struct completion ri_done;
wait_queue_head_t conn_wait;
wait_queue_head_t disconn_wait;
struct completion negotiate_completion;
bool negotiate_done;
struct work_struct disconnect_work;
struct work_struct post_send_credits_work;
spinlock_t lock_new_credits_offered;
int new_credits_offered;
/* Connection parameters defined in [MS-SMBD] */
int receive_credit_max;
int send_credit_target;
int max_send_size;
int max_fragmented_recv_size;
int max_fragmented_send_size;
int max_receive_size;
int keep_alive_interval;
int max_readwrite_size;
enum keep_alive_status keep_alive_requested;
int protocol;
atomic_t send_credits;
atomic_t receive_credits;
int receive_credit_target;
int fragment_reassembly_remaining;
/* Memory registrations */
/* Maximum number of RDMA read/write outstanding on this connection */
int responder_resources;
/* Maximum number of SGEs in a RDMA write/read */
int max_frmr_depth;
* If payload is less than or equal to the threshold,
* use RDMA send/recv to send upper layer I/O.
* If payload is more than the threshold,
* use RDMA read/write through memory registration for I/O.
int rdma_readwrite_threshold;
enum ib_mr_type mr_type;
struct list_head mr_list;
spinlock_t mr_list_lock;
/* The number of available MRs ready for memory registration */
atomic_t mr_ready_count;
atomic_t mr_used_count;
wait_queue_head_t wait_mr;
struct work_struct mr_recovery_work;
/* Used by transport to wait until all MRs are returned */
wait_queue_head_t wait_for_mr_cleanup;
/* Activity accoutning */
atomic_t send_pending;
wait_queue_head_t wait_send_pending;
wait_queue_head_t wait_post_send;
/* Receive queue */
struct list_head receive_queue;
int count_receive_queue;
spinlock_t receive_queue_lock;
struct list_head empty_packet_queue;
int count_empty_packet_queue;
spinlock_t empty_packet_queue_lock;
wait_queue_head_t wait_receive_queues;
/* Reassembly queue */
struct list_head reassembly_queue;
spinlock_t reassembly_queue_lock;
wait_queue_head_t wait_reassembly_queue;
/* total data length of reassembly queue */
int reassembly_data_length;
int reassembly_queue_length;
/* the offset to first buffer in reassembly queue */
int first_entry_offset;
bool send_immediate;
wait_queue_head_t wait_send_queue;
* Indicate if we have received a full packet on the connection
* This is used to identify the first SMBD packet of a assembled
* payload (SMB packet) in reassembly queue so we can return a
* RFC1002 length to upper layer to indicate the length of the SMB
* packet received
bool full_packet_received;
struct workqueue_struct *workqueue;
struct delayed_work idle_timer_work;
/* Memory pool for preallocating buffers */
/* request pool for RDMA send */
struct kmem_cache *request_cache;
mempool_t *request_mempool;
/* response pool for RDMA receive */
struct kmem_cache *response_cache;
mempool_t *response_mempool;
/* for debug purposes */
unsigned int count_get_receive_buffer;
unsigned int count_put_receive_buffer;
unsigned int count_reassembly_queue;
unsigned int count_enqueue_reassembly_queue;
unsigned int count_dequeue_reassembly_queue;
unsigned int count_send_empty;
enum smbd_message_type {
/* SMBD negotiation request packet [MS-SMBD] 2.2.1 */
struct smbd_negotiate_req {
__le16 min_version;
__le16 max_version;
__le16 reserved;
__le16 credits_requested;
__le32 preferred_send_size;
__le32 max_receive_size;
__le32 max_fragmented_size;
} __packed;
/* SMBD negotiation response packet [MS-SMBD] 2.2.2 */
struct smbd_negotiate_resp {
__le16 min_version;
__le16 max_version;
__le16 negotiated_version;
__le16 reserved;
__le16 credits_requested;
__le16 credits_granted;
__le32 status;
__le32 max_readwrite_size;
__le32 preferred_send_size;
__le32 max_receive_size;
__le32 max_fragmented_size;
} __packed;
/* SMBD data transfer packet with payload [MS-SMBD] 2.2.3 */
struct smbd_data_transfer {
__le16 credits_requested;
__le16 credits_granted;
__le16 flags;
__le16 reserved;
__le32 remaining_data_length;
__le32 data_offset;
__le32 data_length;
__le32 padding;
__u8 buffer[];
} __packed;
/* The packet fields for a registered RDMA buffer */
struct smbd_buffer_descriptor_v1 {
__le64 offset;
__le32 token;
__le32 length;
} __packed;
/* Default maximum number of SGEs in a RDMA send/recv */
/* The context for a SMBD request */
struct smbd_request {
struct smbd_connection *info;
struct ib_cqe cqe;
/* the SGE entries for this packet */
struct ib_sge sge[SMBDIRECT_MAX_SGE];
int num_sge;
/* SMBD packet header follows this structure */
u8 packet[];
/* The context for a SMBD response */
struct smbd_response {
struct smbd_connection *info;
struct ib_cqe cqe;
struct ib_sge sge;
enum smbd_message_type type;
/* Link to receive queue or reassembly queue */
struct list_head list;
/* Indicate if this is the 1st packet of a payload */
bool first_segment;
/* SMBD packet header and payload follows this structure */
u8 packet[];
/* Create a SMBDirect session */
struct smbd_connection *smbd_get_connection(
struct TCP_Server_Info *server, struct sockaddr *dstaddr);
/* Reconnect SMBDirect session */
int smbd_reconnect(struct TCP_Server_Info *server);
/* Destroy SMBDirect session */
void smbd_destroy(struct TCP_Server_Info *server);
/* Interface for carrying upper layer I/O through send/recv */
int smbd_recv(struct smbd_connection *info, struct msghdr *msg);
int smbd_send(struct TCP_Server_Info *server,
int num_rqst, struct smb_rqst *rqst);
enum mr_state {
struct smbd_mr {
struct smbd_connection *conn;
struct list_head list;
enum mr_state state;
struct ib_mr *mr;
struct scatterlist *sgl;
int sgl_count;
enum dma_data_direction dir;
union {
struct ib_reg_wr wr;
struct ib_send_wr inv_wr;
struct ib_cqe cqe;
bool need_invalidate;
struct completion invalidate_done;
/* Interfaces to register and deregister MR for RDMA read/write */
struct smbd_mr *smbd_register_mr(
struct smbd_connection *info, struct page *pages[], int num_pages,
int offset, int tailsz, bool writing, bool need_invalidate);
int smbd_deregister_mr(struct smbd_mr *mr);
#define cifs_rdma_enabled(server) 0
struct smbd_connection {};
static inline void *smbd_get_connection(
struct TCP_Server_Info *server, struct sockaddr *dstaddr) {return NULL;}
static inline int smbd_reconnect(struct TCP_Server_Info *server) {return -1; }
static inline void smbd_destroy(struct TCP_Server_Info *server) {}
static inline int smbd_recv(struct smbd_connection *info, struct msghdr *msg) {return -1; }
static inline int smbd_send(struct TCP_Server_Info *server, int num_rqst, struct smb_rqst *rqst) {return -1; }