Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / include / scsi / libiscsi.h
diff --git a/kernel/include/scsi/libiscsi.h b/kernel/include/scsi/libiscsi.h
new file mode 100644 (file)
index 0000000..4d1c46a
--- /dev/null
@@ -0,0 +1,495 @@
+/*
+ * iSCSI lib definitions
+ *
+ * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
+ * Copyright (C) 2004 - 2006 Mike Christie
+ * Copyright (C) 2004 - 2005 Dmitry Yusupov
+ * Copyright (C) 2004 - 2005 Alex Aizman
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+#ifndef LIBISCSI_H
+#define LIBISCSI_H
+
+#include <linux/types.h>
+#include <linux/wait.h>
+#include <linux/mutex.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+#include <linux/kfifo.h>
+#include <scsi/iscsi_proto.h>
+#include <scsi/iscsi_if.h>
+#include <scsi/scsi_transport_iscsi.h>
+
+struct scsi_transport_template;
+struct scsi_host_template;
+struct scsi_device;
+struct Scsi_Host;
+struct scsi_target;
+struct scsi_cmnd;
+struct socket;
+struct iscsi_transport;
+struct iscsi_cls_session;
+struct iscsi_cls_conn;
+struct iscsi_session;
+struct iscsi_nopin;
+struct device;
+
+#define ISCSI_DEF_XMIT_CMDS_MAX        128     /* must be power of 2 */
+#define ISCSI_MGMT_CMDS_MAX    15
+
+#define ISCSI_DEF_CMD_PER_LUN  32
+
+/* Task Mgmt states */
+enum {
+       TMF_INITIAL,
+       TMF_QUEUED,
+       TMF_SUCCESS,
+       TMF_FAILED,
+       TMF_TIMEDOUT,
+       TMF_NOT_FOUND,
+};
+
+#define ISID_SIZE                      6
+
+/* Connection suspend "bit" */
+#define ISCSI_SUSPEND_BIT              1
+
+#define ISCSI_ITT_MASK                 0x1fff
+#define ISCSI_TOTAL_CMDS_MAX           4096
+/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
+#define ISCSI_TOTAL_CMDS_MIN           16
+#define ISCSI_AGE_SHIFT                        28
+#define ISCSI_AGE_MASK                 0xf
+
+#define ISCSI_ADDRESS_BUF_LEN          64
+
+enum {
+       /* this is the maximum possible storage for AHSs */
+       ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
+                               sizeof(struct iscsi_rlength_ahdr),
+       ISCSI_DIGEST_SIZE = sizeof(__u32),
+};
+
+
+enum {
+       ISCSI_TASK_FREE,
+       ISCSI_TASK_COMPLETED,
+       ISCSI_TASK_PENDING,
+       ISCSI_TASK_RUNNING,
+       ISCSI_TASK_ABRT_TMF,            /* aborted due to TMF */
+       ISCSI_TASK_ABRT_SESS_RECOV,     /* aborted due to session recovery */
+       ISCSI_TASK_REQUEUE_SCSIQ,       /* qcmd requeueing to scsi-ml */
+};
+
+struct iscsi_r2t_info {
+       __be32                  ttt;            /* copied from R2T */
+       __be32                  exp_statsn;     /* copied from R2T */
+       uint32_t                data_length;    /* copied from R2T */
+       uint32_t                data_offset;    /* copied from R2T */
+       int                     data_count;     /* DATA-Out payload progress */
+       int                     datasn;
+       /* LLDs should set/update these values */
+       int                     sent;           /* R2T sequence progress */
+};
+
+struct iscsi_task {
+       /*
+        * Because LLDs allocate their hdr differently, this is a pointer
+        * and length to that storage. It must be setup at session
+        * creation time.
+        */
+       struct iscsi_hdr        *hdr;
+       unsigned short          hdr_max;
+       unsigned short          hdr_len;        /* accumulated size of hdr used */
+       /* copied values in case we need to send tmfs */
+       itt_t                   hdr_itt;
+       __be32                  cmdsn;
+       struct scsi_lun         lun;
+
+       int                     itt;            /* this ITT */
+
+       unsigned                imm_count;      /* imm-data (bytes)   */
+       /* offset in unsolicited stream (bytes); */
+       struct iscsi_r2t_info   unsol_r2t;
+       char                    *data;          /* mgmt payload */
+       unsigned                data_count;
+       struct scsi_cmnd        *sc;            /* associated SCSI cmd*/
+       struct iscsi_conn       *conn;          /* used connection    */
+
+       /* data processing tracking */
+       unsigned long           last_xfer;
+       unsigned long           last_timeout;
+       bool                    have_checked_conn;
+
+       /* T10 protection information */
+       bool                    protected;
+
+       /* state set/tested under session->lock */
+       int                     state;
+       atomic_t                refcount;
+       struct list_head        running;        /* running cmd list */
+       void                    *dd_data;       /* driver/transport data */
+};
+
+static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
+{
+       return task->unsol_r2t.data_length > task->unsol_r2t.sent;
+}
+
+static inline void* iscsi_next_hdr(struct iscsi_task *task)
+{
+       return (void*)task->hdr + task->hdr_len;
+}
+
+/* Connection's states */
+enum {
+       ISCSI_CONN_INITIAL_STAGE,
+       ISCSI_CONN_STARTED,
+       ISCSI_CONN_STOPPED,
+       ISCSI_CONN_CLEANUP_WAIT,
+};
+
+struct iscsi_conn {
+       struct iscsi_cls_conn   *cls_conn;      /* ptr to class connection */
+       void                    *dd_data;       /* iscsi_transport data */
+       struct iscsi_session    *session;       /* parent session */
+       /*
+        * conn_stop() flag: stop to recover, stop to terminate
+        */
+        int                    stop_stage;
+       struct timer_list       transport_timer;
+       unsigned long           last_recv;
+       unsigned long           last_ping;
+       int                     ping_timeout;
+       int                     recv_timeout;
+       struct iscsi_task       *ping_task;
+
+       /* iSCSI connection-wide sequencing */
+       uint32_t                exp_statsn;
+       uint32_t                statsn;
+
+       /* control data */
+       int                     id;             /* CID */
+       int                     c_stage;        /* connection state */
+       /*
+        * Preallocated buffer for pdus that have data but do not
+        * originate from scsi-ml. We never have two pdus using the
+        * buffer at the same time. It is only allocated to
+        * the default max recv size because the pdus we support
+        * should always fit in this buffer
+        */
+       char                    *data;
+       struct iscsi_task       *login_task;    /* mtask used for login/text */
+       struct iscsi_task       *task;          /* xmit task in progress */
+
+       /* xmit */
+       struct list_head        mgmtqueue;      /* mgmt (control) xmit queue */
+       struct list_head        cmdqueue;       /* data-path cmd queue */
+       struct list_head        requeue;        /* tasks needing another run */
+       struct work_struct      xmitwork;       /* per-conn. xmit workqueue */
+       unsigned long           suspend_tx;     /* suspend Tx */
+       unsigned long           suspend_rx;     /* suspend Rx */
+
+       /* abort */
+       wait_queue_head_t       ehwait;         /* used in eh_abort() */
+       struct iscsi_tm         tmhdr;
+       struct timer_list       tmf_timer;
+       int                     tmf_state;      /* see TMF_INITIAL, etc.*/
+
+       /* negotiated params */
+       unsigned                max_recv_dlength; /* initiator_max_recv_dsl*/
+       unsigned                max_xmit_dlength; /* target_max_recv_dsl */
+       int                     hdrdgst_en;
+       int                     datadgst_en;
+       int                     ifmarker_en;
+       int                     ofmarker_en;
+       /* values userspace uses to id a conn */
+       int                     persistent_port;
+       char                    *persistent_address;
+
+       unsigned                max_segment_size;
+       unsigned                tcp_xmit_wsf;
+       unsigned                tcp_recv_wsf;
+       uint16_t                keepalive_tmo;
+       uint16_t                local_port;
+       uint8_t                 tcp_timestamp_stat;
+       uint8_t                 tcp_nagle_disable;
+       uint8_t                 tcp_wsf_disable;
+       uint8_t                 tcp_timer_scale;
+       uint8_t                 tcp_timestamp_en;
+       uint8_t                 fragment_disable;
+       uint8_t                 ipv4_tos;
+       uint8_t                 ipv6_traffic_class;
+       uint8_t                 ipv6_flow_label;
+       uint8_t                 is_fw_assigned_ipv6;
+       char                    *local_ipaddr;
+
+       /* MIB-statistics */
+       uint64_t                txdata_octets;
+       uint64_t                rxdata_octets;
+       uint32_t                scsicmd_pdus_cnt;
+       uint32_t                dataout_pdus_cnt;
+       uint32_t                scsirsp_pdus_cnt;
+       uint32_t                datain_pdus_cnt;
+       uint32_t                r2t_pdus_cnt;
+       uint32_t                tmfcmd_pdus_cnt;
+       int32_t                 tmfrsp_pdus_cnt;
+
+       /* custom statistics */
+       uint32_t                eh_abort_cnt;
+       uint32_t                fmr_unalign_cnt;
+};
+
+struct iscsi_pool {
+       struct kfifo            queue;          /* FIFO Queue */
+       void                    **pool;         /* Pool of elements */
+       int                     max;            /* Max number of elements */
+};
+
+/* Session's states */
+enum {
+       ISCSI_STATE_FREE = 1,
+       ISCSI_STATE_LOGGED_IN,
+       ISCSI_STATE_FAILED,
+       ISCSI_STATE_TERMINATE,
+       ISCSI_STATE_IN_RECOVERY,
+       ISCSI_STATE_RECOVERY_FAILED,
+       ISCSI_STATE_LOGGING_OUT,
+};
+
+struct iscsi_session {
+       struct iscsi_cls_session *cls_session;
+       /*
+        * Syncs up the scsi eh thread with the iscsi eh thread when sending
+        * task management functions. This must be taken before the session
+        * and recv lock.
+        */
+       struct mutex            eh_mutex;
+
+       /* iSCSI session-wide sequencing */
+       uint32_t                cmdsn;
+       uint32_t                exp_cmdsn;
+       uint32_t                max_cmdsn;
+
+       /* This tracks the reqs queued into the initiator */
+       uint32_t                queued_cmdsn;
+
+       /* configuration */
+       int                     abort_timeout;
+       int                     lu_reset_timeout;
+       int                     tgt_reset_timeout;
+       int                     initial_r2t_en;
+       unsigned short          max_r2t;
+       int                     imm_data_en;
+       unsigned                first_burst;
+       unsigned                max_burst;
+       int                     time2wait;
+       int                     time2retain;
+       int                     pdu_inorder_en;
+       int                     dataseq_inorder_en;
+       int                     erl;
+       int                     fast_abort;
+       int                     tpgt;
+       char                    *username;
+       char                    *username_in;
+       char                    *password;
+       char                    *password_in;
+       char                    *targetname;
+       char                    *targetalias;
+       char                    *ifacename;
+       char                    *initiatorname;
+       char                    *boot_root;
+       char                    *boot_nic;
+       char                    *boot_target;
+       char                    *portal_type;
+       char                    *discovery_parent_type;
+       uint16_t                discovery_parent_idx;
+       uint16_t                def_taskmgmt_tmo;
+       uint16_t                tsid;
+       uint8_t                 auto_snd_tgt_disable;
+       uint8_t                 discovery_sess;
+       uint8_t                 chap_auth_en;
+       uint8_t                 discovery_logout_en;
+       uint8_t                 bidi_chap_en;
+       uint8_t                 discovery_auth_optional;
+       uint8_t                 isid[ISID_SIZE];
+
+       /* control data */
+       struct iscsi_transport  *tt;
+       struct Scsi_Host        *host;
+       struct iscsi_conn       *leadconn;      /* leading connection */
+       /* Between the forward and the backward locks exists a strict locking
+        * hierarchy. The mutual exclusion zone protected by the forward lock
+        * can enclose the mutual exclusion zone protected by the backward lock
+        * but not vice versa.
+        */
+       spinlock_t              frwd_lock;      /* protects session state, *
+                                                * cmdsn, queued_cmdsn     *
+                                                * session resources:      *
+                                                * - cmdpool kfifo_out ,   *
+                                                * - mgmtpool,             */
+       spinlock_t              back_lock;      /* protects cmdsn_exp      *
+                                                * cmdsn_max,              *
+                                                * cmdpool kfifo_in        */
+       int                     state;          /* session state           */
+       int                     age;            /* counts session re-opens */
+
+       int                     scsi_cmds_max;  /* max scsi commands */
+       int                     cmds_max;       /* size of cmds array */
+       struct iscsi_task       **cmds;         /* Original Cmds arr */
+       struct iscsi_pool       cmdpool;        /* PDU's pool */
+       void                    *dd_data;       /* LLD private data */
+};
+
+enum {
+       ISCSI_HOST_SETUP,
+       ISCSI_HOST_REMOVED,
+};
+
+struct iscsi_host {
+       char                    *initiatorname;
+       /* hw address or netdev iscsi connection is bound to */
+       char                    *hwaddress;
+       char                    *netdev;
+
+       wait_queue_head_t       session_removal_wq;
+       /* protects sessions and state */
+       spinlock_t              lock;
+       int                     num_sessions;
+       int                     state;
+
+       struct workqueue_struct *workq;
+       char                    workq_name[20];
+};
+
+/*
+ * scsi host template
+ */
+extern int iscsi_eh_abort(struct scsi_cmnd *sc);
+extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
+extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
+extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
+extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
+
+/*
+ * iSCSI host helpers.
+ */
+#define iscsi_host_priv(_shost) \
+       (shost_priv(_shost) + sizeof(struct iscsi_host))
+
+extern int iscsi_host_set_param(struct Scsi_Host *shost,
+                               enum iscsi_host_param param, char *buf,
+                               int buflen);
+extern int iscsi_host_get_param(struct Scsi_Host *shost,
+                               enum iscsi_host_param param, char *buf);
+extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
+extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
+                                         int dd_data_size,
+                                         bool xmit_can_sleep);
+extern void iscsi_host_remove(struct Scsi_Host *shost);
+extern void iscsi_host_free(struct Scsi_Host *shost);
+extern int iscsi_target_alloc(struct scsi_target *starget);
+
+/*
+ * session management
+ */
+extern struct iscsi_cls_session *
+iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
+                   uint16_t, int, int, uint32_t, unsigned int);
+extern void iscsi_session_teardown(struct iscsi_cls_session *);
+extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
+extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
+                          enum iscsi_param param, char *buf, int buflen);
+extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
+                                  enum iscsi_param param, char *buf);
+
+#define iscsi_session_printk(prefix, _sess, fmt, a...) \
+       iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
+
+/*
+ * connection management
+ */
+extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
+                                              int, uint32_t);
+extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
+extern int iscsi_conn_start(struct iscsi_cls_conn *);
+extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
+extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
+                          int);
+extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
+extern void iscsi_session_failure(struct iscsi_session *session,
+                                 enum iscsi_err err);
+extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
+                               enum iscsi_param param, char *buf);
+extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
+                                    enum iscsi_param param, char *buf);
+extern void iscsi_suspend_tx(struct iscsi_conn *conn);
+extern void iscsi_suspend_queue(struct iscsi_conn *conn);
+extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
+
+#define iscsi_conn_printk(prefix, _c, fmt, a...) \
+       iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
+                             fmt, ##a)
+
+/*
+ * pdu and task processing
+ */
+extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
+extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
+                                   struct iscsi_r2t_info *r2t,
+                                   struct iscsi_data *hdr);
+extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
+                               char *, uint32_t);
+extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
+                             char *, int);
+extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
+                               char *, int);
+extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
+extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
+extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
+extern void iscsi_requeue_task(struct iscsi_task *task);
+extern void iscsi_put_task(struct iscsi_task *task);
+extern void __iscsi_put_task(struct iscsi_task *task);
+extern void __iscsi_get_task(struct iscsi_task *task);
+extern void iscsi_complete_scsi_task(struct iscsi_task *task,
+                                    uint32_t exp_cmdsn, uint32_t max_cmdsn);
+
+/*
+ * generic helpers
+ */
+extern void iscsi_pool_free(struct iscsi_pool *);
+extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
+extern int iscsi_switch_str_param(char **, char *);
+
+/*
+ * inline functions to deal with padding.
+ */
+static inline unsigned int
+iscsi_padded(unsigned int len)
+{
+       return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
+}
+
+static inline unsigned int
+iscsi_padding(unsigned int len)
+{
+       len &= (ISCSI_PAD_LEN - 1);
+       if (len)
+               len = ISCSI_PAD_LEN - len;
+       return len;
+}
+
+#endif