/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
 */

#ifndef _SYS_CRYPTO_SCHED_IMPL_H
#define _SYS_CRYPTO_SCHED_IMPL_H

/*
 * Scheduler internal structures.
 */

#ifdef __cplusplus
extern "C" {
#endif

#include <sys/types.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/door.h>
#include <sys/crypto/api.h>
#include <sys/crypto/spi.h>
#include <sys/crypto/impl.h>
#include <sys/crypto/common.h>
#include <sys/crypto/ops_impl.h>

typedef void (kcf_func_t)(void *, int);

typedef enum kcf_req_status {
        REQ_ALLOCATED = 1,
        REQ_WAITING,            /* At the framework level */
        REQ_INPROGRESS,         /* At the provider level */
        REQ_DONE,
        REQ_CANCELED
} kcf_req_status_t;

typedef enum kcf_call_type {
        CRYPTO_SYNCH = 1,
        CRYPTO_ASYNCH
} kcf_call_type_t;

#define CHECK_FASTPATH(crq, pd) ((crq) == NULL ||       \
        !((crq)->cr_flag & CRYPTO_ALWAYS_QUEUE)) &&     \
        (pd)->pd_prov_type == CRYPTO_SW_PROVIDER

#define KCF_KMFLAG(crq) (((crq) == NULL) ? KM_SLEEP : KM_NOSLEEP)

/*
 * The framework keeps an internal handle to use in the adaptive
 * asynchronous case. This is the case when a client has the
 * CRYPTO_ALWAYS_QUEUE bit clear and a software provider is used for
 * the request. The request is completed in the context of the calling
 * thread and kernel memory must be allocated with KM_NOSLEEP.
 *
 * The framework passes a pointer to the handle in crypto_req_handle_t
 * argument when it calls the SPI of the software provider. The macros
 * KCF_RHNDL() and KCF_SWFP_RHNDL() are used to do this.
 *
 * When a provider asks the framework for kmflag value via
 * crypto_kmflag(9S) we use REQHNDL2_KMFLAG() macro.
 */
extern ulong_t kcf_swprov_hndl;
#define KCF_RHNDL(kmflag) (((kmflag) == KM_SLEEP) ? NULL : &kcf_swprov_hndl)
#define KCF_SWFP_RHNDL(crq) (((crq) == NULL) ? NULL : &kcf_swprov_hndl)
#define REQHNDL2_KMFLAG(rhndl) \
        ((rhndl == &kcf_swprov_hndl) ? KM_NOSLEEP : KM_SLEEP)

/* Internal call_req flags. They start after the public ones in api.h */

#define CRYPTO_SETDUAL  0x00001000      /* Set the 'cont' boolean before */
                                        /* submitting the request */
#define KCF_ISDUALREQ(crq)      \
        (((crq) == NULL) ? B_FALSE : (crq->cr_flag & CRYPTO_SETDUAL))

typedef struct kcf_prov_tried {
        kcf_provider_desc_t     *pt_pd;
        struct kcf_prov_tried   *pt_next;
} kcf_prov_tried_t;

/* Must be different from KM_SLEEP and KM_NOSLEEP */
#define KCF_HOLD_PROV   0x1000

#define IS_FG_SUPPORTED(mdesc, fg)              \
        (((mdesc)->pm_mech_info.cm_func_group_mask & (fg)) != 0)

#define IS_PROVIDER_TRIED(pd, tlist)            \
        (tlist != NULL && is_in_triedlist(pd, tlist))

#define IS_RECOVERABLE(error)                   \
        (error == CRYPTO_BUFFER_TOO_BIG ||      \
        error == CRYPTO_BUSY ||                 \
        error == CRYPTO_DEVICE_ERROR ||         \
        error == CRYPTO_DEVICE_MEMORY ||        \
        error == CRYPTO_KEY_SIZE_RANGE ||       \
        error == CRYPTO_NO_PERMISSION)

#define KCF_ATOMIC_INCR(x)      atomic_inc_32(&(x))
#define KCF_ATOMIC_DECR(x)      atomic_dec_32(&(x))

/*
 * Node structure for synchronous requests.
 */
typedef struct kcf_sreq_node {
        /* Should always be the first field in this structure */
        kcf_call_type_t         sn_type;
        /*
         * sn_cv and sr_lock are used to wait for the
         * operation to complete. sn_lock also protects
         * the sn_state field.
         */
        kcondvar_t              sn_cv;
        kmutex_t                sn_lock;
        kcf_req_status_t        sn_state;

        /*
         * Return value from the operation. This will be
         * one of the CRYPTO_* errors defined in common.h.
         */
        int                     sn_rv;

        /*
         * parameters to call the SPI with. This can be
         * a pointer as we know the caller context/stack stays.
         */
        struct kcf_req_params   *sn_params;

        /* Internal context for this request */
        struct kcf_context      *sn_context;

        /* Provider handling this request */
        kcf_provider_desc_t     *sn_provider;

        kcf_prov_cpu_t          *sn_mp;
} kcf_sreq_node_t;

/*
 * Node structure for asynchronous requests. A node can be on
 * on a chain of requests hanging of the internal context
 * structure and can be in the global software provider queue.
 */
typedef struct kcf_areq_node {
        /* Should always be the first field in this structure */
        kcf_call_type_t         an_type;

        /* an_lock protects the field an_state  */
        kmutex_t                an_lock;
        kcf_req_status_t        an_state;
        crypto_call_req_t       an_reqarg;

        /*
         * parameters to call the SPI with. We need to
         * save the params since the caller stack can go away.
         */
        struct kcf_req_params   an_params;

        /*
         * The next two fields should be NULL for operations that
         * don't need a context.
         */
        /* Internal context for this request */
        struct kcf_context      *an_context;

        /* next in chain of requests for context */
        struct kcf_areq_node    *an_ctxchain_next;

        kcondvar_t              an_turn_cv;
        boolean_t               an_is_my_turn;
        boolean_t               an_isdual;      /* for internal reuse */

        /*
         * Next and previous nodes in the global software
         * queue. These fields are NULL for a hardware
         * provider since we use a taskq there.
         */
        struct kcf_areq_node    *an_next;
        struct kcf_areq_node    *an_prev;

        /* Provider handling this request */
        kcf_provider_desc_t     *an_provider;
        kcf_prov_cpu_t          *an_mp;
        kcf_prov_tried_t        *an_tried_plist;

        struct kcf_areq_node    *an_idnext;     /* Next in ID hash */
        struct kcf_areq_node    *an_idprev;     /* Prev in ID hash */
        kcondvar_t              an_done;        /* Signal request completion */
        uint_t                  an_refcnt;
} kcf_areq_node_t;

#define KCF_AREQ_REFHOLD(areq) {                \
        atomic_inc_32(&(areq)->an_refcnt);      \
        ASSERT((areq)->an_refcnt != 0);         \
}

#define KCF_AREQ_REFRELE(areq) {                                \
        ASSERT((areq)->an_refcnt != 0);                         \
        membar_exit();                                          \
        if (atomic_dec_32_nv(&(areq)->an_refcnt) == 0)  \
                kcf_free_req(areq);                             \
}

#define GET_REQ_TYPE(arg) *((kcf_call_type_t *)(arg))

#define NOTIFY_CLIENT(areq, err) (*(areq)->an_reqarg.cr_callback_func)(\
        (areq)->an_reqarg.cr_callback_arg, err);

/* For internally generated call requests for dual operations */
typedef struct kcf_call_req {
        crypto_call_req_t       kr_callreq;     /* external client call req */
        kcf_req_params_t        kr_params;      /* Params saved for next call */
        kcf_areq_node_t         *kr_areq;       /* Use this areq */
        off_t                   kr_saveoffset;
        size_t                  kr_savelen;
} kcf_dual_req_t;

/*
 * The following are some what similar to macros in callo.h, which implement
 * callout tables.
 *
 * The lower four bits of the ID are used to encode the table ID to
 * index in to. The REQID_COUNTER_HIGH bit is used to avoid any check for
 * wrap around when generating ID. We assume that there won't be a request
 * which takes more time than 2^^(sizeof (long) - 5) other requests submitted
 * after it. This ensures there won't be any ID collision.
 */
#define REQID_COUNTER_HIGH      (1UL << (8 * sizeof (long) - 1))
#define REQID_COUNTER_SHIFT     4
#define REQID_COUNTER_LOW       (1 << REQID_COUNTER_SHIFT)
#define REQID_TABLES            16
#define REQID_TABLE_MASK        (REQID_TABLES - 1)

#define REQID_BUCKETS           512
#define REQID_BUCKET_MASK       (REQID_BUCKETS - 1)
#define REQID_HASH(id)  (((id) >> REQID_COUNTER_SHIFT) & REQID_BUCKET_MASK)

#define GET_REQID(areq) (areq)->an_reqarg.cr_reqid
#define SET_REQID(areq, val)    GET_REQID(areq) = val

/*
 * Hash table for async requests.
 */
typedef struct kcf_reqid_table {
        kmutex_t                rt_lock;
        crypto_req_id_t         rt_curid;
        kcf_areq_node_t         *rt_idhash[REQID_BUCKETS];
} kcf_reqid_table_t;

/*
 * Global software provider queue structure. Requests to be
 * handled by a SW provider and have the ALWAYS_QUEUE flag set
 * get queued here.
 */
typedef struct kcf_global_swq {
        /*
         * gs_cv and gs_lock are used to wait for new requests.
         * gs_lock protects the changes to the queue.
         */
        kcondvar_t              gs_cv;
        kmutex_t                gs_lock;
        uint_t                  gs_njobs;
        uint_t                  gs_maxjobs;
        kcf_areq_node_t         *gs_first;
        kcf_areq_node_t         *gs_last;
} kcf_global_swq_t;


/*
 * Internal representation of a canonical context. We contain crypto_ctx_t
 * structure in order to have just one memory allocation. The SPI
 * ((crypto_ctx_t *)ctx)->cc_framework_private maps to this structure.
 */
typedef struct kcf_context {
        crypto_ctx_t            kc_glbl_ctx;
        uint_t                  kc_refcnt;
        kmutex_t                kc_in_use_lock;
        /*
         * kc_req_chain_first and kc_req_chain_last are used to chain
         * multiple async requests using the same context. They should be
         * NULL for sync requests.
         */
        kcf_areq_node_t         *kc_req_chain_first;
        kcf_areq_node_t         *kc_req_chain_last;
        kcf_provider_desc_t     *kc_prov_desc;  /* Prov. descriptor */
        kcf_provider_desc_t     *kc_sw_prov_desc;       /* Prov. descriptor */
        kcf_mech_entry_t        *kc_mech;
        struct kcf_context      *kc_secondctx;  /* for dual contexts */
} kcf_context_t;

/*
 * Bump up the reference count on the framework private context. A
 * global context or a request that references this structure should
 * do a hold.
 */
#define KCF_CONTEXT_REFHOLD(ictx) {             \
        atomic_inc_32(&(ictx)->kc_refcnt);      \
        ASSERT((ictx)->kc_refcnt != 0);         \
}

/*
 * Decrement the reference count on the framework private context.
 * When the last reference is released, the framework private
 * context structure is freed along with the global context.
 */
#define KCF_CONTEXT_REFRELE(ictx) {                             \
        ASSERT((ictx)->kc_refcnt != 0);                         \
        membar_exit();                                          \
        if (atomic_dec_32_nv(&(ictx)->kc_refcnt) == 0)  \
                kcf_free_context(ictx);                         \
}

/*
 * Check if we can release the context now. In case of CRYPTO_QUEUED
 * we do not release it as we can do it only after the provider notified
 * us. In case of CRYPTO_BUSY, the client can retry the request using
 * the context, so we do not release the context.
 *
 * This macro should be called only from the final routine in
 * an init/update/final sequence. We do not release the context in case
 * of update operations. We require the consumer to free it
 * explicitly, in case it wants to abandon the operation. This is done
 * as there may be mechanisms in ECB mode that can continue even if
 * an operation on a block fails.
 */
#define KCF_CONTEXT_COND_RELEASE(rv, kcf_ctx) {                 \
        if (KCF_CONTEXT_DONE(rv))                               \
                KCF_CONTEXT_REFRELE(kcf_ctx);                   \
}

/*
 * This macro determines whether we're done with a context.
 */
#define KCF_CONTEXT_DONE(rv)                                    \
        ((rv) != CRYPTO_QUEUED && (rv) != CRYPTO_BUSY &&        \
            (rv) != CRYPTO_BUFFER_TOO_SMALL)

/*
 * A crypto_ctx_template_t is internally a pointer to this struct
 */
typedef struct kcf_ctx_template {
        crypto_kcf_provider_handle_t    ct_prov_handle; /* provider handle */
        uint_t                          ct_generation;  /* generation # */
        size_t                          ct_size;        /* for freeing */
        crypto_spi_ctx_template_t       ct_prov_tmpl;   /* context template */
                                                        /* from the SW prov */
} kcf_ctx_template_t;

/*
 * Structure for pool of threads working on global software queue.
 */
typedef struct kcf_pool {
        uint32_t        kp_threads;             /* Number of threads in pool */
        uint32_t        kp_idlethreads;         /* Idle threads in pool */
        uint32_t        kp_blockedthreads;      /* Blocked threads in pool */

        /*
         * cv & lock for the condition where more threads need to be created.
         */
        kcondvar_t      kp_cv;          /* Creator cond. variable */
        kmutex_t        kp_lock;                /* Creator lock */

} kcf_pool_t;


/*
 * State of a crypto bufcall element.
 */
typedef enum cbuf_state {
        CBUF_FREE = 1,
        CBUF_WAITING,
        CBUF_RUNNING
} cbuf_state_t;

/*
 * Structure of a crypto bufcall element.
 */
typedef struct kcf_cbuf_elem {
        /*
         * lock and cv to wait for CBUF_RUNNING to be done
         * kc_lock also protects kc_state.
         */
        kmutex_t                kc_lock;
        kcondvar_t              kc_cv;
        cbuf_state_t            kc_state;

        struct kcf_cbuf_elem    *kc_next;
        struct kcf_cbuf_elem    *kc_prev;

        void                    (*kc_func)(void *arg);
        void                    *kc_arg;
} kcf_cbuf_elem_t;

/*
 * State of a notify element.
 */
typedef enum ntfy_elem_state {
        NTFY_WAITING = 1,
        NTFY_RUNNING
} ntfy_elem_state_t;

/*
 * Structure of a notify list element.
 */
typedef struct kcf_ntfy_elem {
        /*
         * lock and cv to wait for NTFY_RUNNING to be done.
         * kn_lock also protects kn_state.
         */
        kmutex_t                        kn_lock;
        kcondvar_t                      kn_cv;
        ntfy_elem_state_t               kn_state;

        struct kcf_ntfy_elem            *kn_next;
        struct kcf_ntfy_elem            *kn_prev;

        crypto_notify_callback_t        kn_func;
        uint32_t                        kn_event_mask;
} kcf_ntfy_elem_t;


/*
 * The following values are based on the assumption that it would
 * take around eight cpus to load a hardware provider (This is true for
 * at least one product) and a kernel client may come from different
 * low-priority interrupt levels. We will have CYRPTO_TASKQ_MIN number
 * of cached taskq entries. The CRYPTO_TASKQ_MAX number is based on
 * a throughput of 1GB/s using 512-byte buffers. These are just
 * reasonable estimates and might need to change in future.
 */
#define CRYPTO_TASKQ_THREADS    8
#define CYRPTO_TASKQ_MIN        64
#define CRYPTO_TASKQ_MAX        2 * 1024 * 1024

extern int crypto_taskq_threads;
extern int crypto_taskq_minalloc;
extern int crypto_taskq_maxalloc;
extern kcf_global_swq_t *gswq;
extern int kcf_maxthreads;
extern int kcf_minthreads;

/*
 * All pending crypto bufcalls are put on a list. cbuf_list_lock
 * protects changes to this list.
 */
extern kmutex_t cbuf_list_lock;
extern kcondvar_t cbuf_list_cv;

/*
 * All event subscribers are put on a list. kcf_notify_list_lock
 * protects changes to this list.
 */
extern kmutex_t ntfy_list_lock;
extern kcondvar_t ntfy_list_cv;

boolean_t kcf_get_next_logical_provider_member(kcf_provider_desc_t *,
    kcf_provider_desc_t *, kcf_provider_desc_t **);
extern int kcf_get_hardware_provider(crypto_mech_type_t, crypto_key_t *,
    crypto_mech_type_t, crypto_key_t *,
    kcf_provider_desc_t *, kcf_provider_desc_t **,
    crypto_func_group_t);
extern int kcf_get_hardware_provider_nomech(offset_t, offset_t,
    kcf_provider_desc_t *, kcf_provider_desc_t **);
extern void kcf_free_triedlist(kcf_prov_tried_t *);
extern kcf_prov_tried_t *kcf_insert_triedlist(kcf_prov_tried_t **,
    kcf_provider_desc_t *, int);
extern kcf_provider_desc_t *kcf_get_mech_provider(crypto_mech_type_t,
    crypto_key_t *, kcf_mech_entry_t **, int *, kcf_prov_tried_t *,
    crypto_func_group_t, size_t);
extern kcf_provider_desc_t *kcf_get_dual_provider(crypto_mechanism_t *,
    crypto_key_t *, crypto_mechanism_t *, crypto_key_t *,
    kcf_mech_entry_t **, crypto_mech_type_t *,
    crypto_mech_type_t *, int *, kcf_prov_tried_t *,
    crypto_func_group_t, crypto_func_group_t, size_t);
extern crypto_ctx_t *kcf_new_ctx(crypto_call_req_t  *, kcf_provider_desc_t *,
    crypto_session_id_t);
extern int kcf_submit_request(kcf_provider_desc_t *, crypto_ctx_t *,
    crypto_call_req_t *, kcf_req_params_t *, boolean_t);
extern void kcf_sched_init(void);
extern void kcf_sched_start(void);
extern void kcf_sop_done(kcf_sreq_node_t *, int);
extern void kcf_aop_done(kcf_areq_node_t *, int);
extern int common_submit_request(kcf_provider_desc_t *,
    crypto_ctx_t *, kcf_req_params_t *, crypto_req_handle_t);
extern void kcf_free_context(kcf_context_t *);

extern struct modctl *kcf_get_modctl(crypto_provider_info_t *);
extern void kcf_free_req(kcf_areq_node_t *areq);
extern void crypto_bufcall_service(void);

extern void kcf_walk_ntfylist(uint32_t, void *);
extern void kcf_do_notify(kcf_provider_desc_t *, boolean_t);

extern kcf_dual_req_t *kcf_alloc_req(crypto_call_req_t *);
extern void kcf_next_req(void *, int);
extern void kcf_last_req(void *, int);

#ifdef __cplusplus
}
#endif

#endif /* _SYS_CRYPTO_SCHED_IMPL_H */