/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
 * Copyright 2024 Oxide Computer Company
 */

#ifndef _SYS_SDT_IMPL_H
#define _SYS_SDT_IMPL_H

#ifdef  __cplusplus
extern "C" {
#endif

#include <sys/dtrace.h>

#if defined(__i386) || defined(__amd64)
#define SDT_CALL        0xe8
#define SDT_NOP         0x90
#define SDT_RET         0xc3

/*
 * The kernel runtime linker (krtld) will perform the patching described above
 * and note the offset of the instruction that was patched for the SDT module
 * in the sdpd_offset field of the sdt_probedesc_t structure.  In the case of
 * a tail call, this index will be a RET otherwise it will be a NOP.
 */
#define SDT_OFF_RET_IDX 3

typedef uint8_t sdt_instr_t;
#else
typedef uint32_t sdt_instr_t;
#endif

typedef struct sdt_provider {
        char                    *sdtp_name;     /* name of provider */
        char                    *sdtp_prefix;   /* prefix for probe names */
        dtrace_pattr_t          *sdtp_attr;     /* stability attributes */
        uint32_t                sdtp_priv;      /* privilege, if any */
        dtrace_provider_id_t    sdtp_id;        /* provider ID */
} sdt_provider_t;

extern sdt_provider_t sdt_providers[];          /* array of providers */

typedef struct sdt_probe {
        sdt_provider_t  *sdp_provider;          /* provider */
        char            *sdp_name;              /* name of probe */
        int             sdp_namelen;            /* length of allocated name */
        dtrace_id_t     sdp_id;                 /* probe ID */
        struct modctl   *sdp_ctl;               /* modctl for module */
        int             sdp_loadcnt;            /* load count for module */
        int             sdp_primary;            /* non-zero if primary mod */
        sdt_instr_t     *sdp_patchpoint;        /* patch point */
        sdt_instr_t     sdp_patchval;           /* instruction to patch */
        sdt_instr_t     sdp_savedval;           /* saved instruction value */
        boolean_t       sdp_is_tailcall;        /* invoked as a tail call */
        struct sdt_probe *sdp_next;             /* next probe */
        struct sdt_probe *sdp_hashnext;         /* next on hash */
} sdt_probe_t;

typedef struct sdt_argdesc {
        const char *sda_provider;               /* provider for arg */
        const char *sda_name;                   /* name of probe */
        const int sda_ndx;                      /* argument index */
        const int sda_mapping;                  /* mapping of argument */
        const char *sda_native;                 /* native type of argument */
        const char *sda_xlate;                  /* translated type of arg */
} sdt_argdesc_t;

extern void sdt_getargdesc(void *, dtrace_id_t, void *, dtrace_argdesc_t *);
extern int sdt_mode(void *, dtrace_id_t, void *);

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_SDT_IMPL_H */