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Diffstat (limited to 'fs/cifs/smbdirect.h')
| -rw-r--r-- | fs/cifs/smbdirect.h | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/fs/cifs/smbdirect.h b/fs/cifs/smbdirect.h new file mode 100644 index 000000000..b5c240ff2 --- /dev/null +++ b/fs/cifs/smbdirect.h @@ -0,0 +1,339 @@ +/* + * Copyright (C) 2017, Microsoft Corporation. + * + * Author(s): Long Li <longli@microsoft.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + */ +#ifndef _SMBDIRECT_H +#define _SMBDIRECT_H + +#ifdef CONFIG_CIFS_SMB_DIRECT +#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 { + KEEP_ALIVE_NONE, + KEEP_ALIVE_PENDING, + KEEP_ALIVE_SENT, +}; + +enum smbd_connection_status { + SMBD_CREATED, + SMBD_CONNECTING, + SMBD_CONNECTED, + SMBD_NEGOTIATE_FAILED, + SMBD_DISCONNECTING, + SMBD_DISCONNECTED, + SMBD_DESTROYED +}; + +/* + * 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 wait_destroy; + + struct completion negotiate_completion; + bool negotiate_done; + + struct work_struct destroy_work; + struct work_struct disconnect_work; + struct work_struct recv_done_work; + struct work_struct post_send_credits_work; + + spinlock_t lock_new_credits_offered; + int new_credits_offered; + + /* Connection parameters defined in [MS-SMBD] 3.1.1.1 */ + 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 */ + /* Pending reqeusts issued from upper layer */ + int smbd_send_pending; + wait_queue_head_t wait_smbd_send_pending; + + int smbd_recv_pending; + wait_queue_head_t wait_smbd_recv_pending; + + atomic_t send_pending; + wait_queue_head_t wait_send_pending; + atomic_t send_payload_pending; + wait_queue_head_t wait_send_payload_pending; + + /* 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; + struct delayed_work send_immediate_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_NEGOTIATE_RESP, + SMBD_TRANSFER_DATA, +}; + +#define SMB_DIRECT_RESPONSE_REQUESTED 0x0001 + +/* 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 */ +#define SMBDIRECT_MAX_SGE 16 +/* The context for a SMBD request */ +struct smbd_request { + struct smbd_connection *info; + struct ib_cqe cqe; + + /* true if this request carries upper layer payload */ + bool has_payload; + + /* 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 smbd_connection *info); + +/* 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 { + MR_READY, + MR_REGISTERED, + MR_INVALIDATED, + MR_ERROR +}; + +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); + +#else +#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 smbd_connection *info) {} +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; } +#endif + +#endif |