bsd/sys/fasttrap_impl.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #ifndef _FASTTRAP_IMPL_H
  28 #define _FASTTRAP_IMPL_H
  29
  30 /*
  31  * #pragma ident        "@(#)fasttrap_impl.h    1.14    08/04/09 SMI"
  32  */
  33
  34 #include <sys/types.h>
  35 #include <sys/dtrace.h>
  36 #include <sys/proc.h>
  37 #include <sys/user.h>
  38 #include <sys/fasttrap.h>
  39 #include <sys/fasttrap_isa.h>
  40
  41 /* Solaris proc_t is the struct. Darwin's proc_t is a pointer to it. */
  42 #define proc_t struct proc /* Steer clear of the Darwin typedef for proc_t */
  43
  44 #ifdef  __cplusplus
  45 extern "C" {
  46 #endif
  47
  48 /*
  49  * Fasttrap Providers, Probes and Tracepoints
  50  *
  51  * Each Solaris process can have multiple providers -- the pid provider as
  52  * well as any number of user-level statically defined tracing (USDT)
  53  * providers. Those providers are each represented by a fasttrap_provider_t.
  54  * All providers for a given process have a pointer to a shared
  55  * fasttrap_proc_t. The fasttrap_proc_t has two states: active or defunct.
  56  * When the count of active providers goes to zero it becomes defunct; a
  57  * provider drops its active count when it is removed individually or as part
  58  * of a mass removal when a process exits or performs an exec.
  59  *
  60  * Each probe is represented by a fasttrap_probe_t which has a pointer to
  61  * its associated provider as well as a list of fasttrap_id_tp_t structures
  62  * which are tuples combining a fasttrap_id_t and a fasttrap_tracepoint_t.
  63  * A fasttrap_tracepoint_t represents the actual point of instrumentation
  64  * and it contains two lists of fasttrap_id_t structures (to be fired pre-
  65  * and post-instruction emulation) that identify the probes attached to the
  66  * tracepoint. Tracepoints also have a pointer to the fasttrap_proc_t for the
  67  * process they trace which is used when looking up a tracepoint both when a
  68  * probe fires and when enabling and disabling probes.
  69  *
  70  * It's important to note that probes are preallocated with the necessary
  71  * number of tracepoints, but that tracepoints can be shared by probes and
  72  * swapped between probes. If a probe's preallocated tracepoint is enabled
  73  * (and, therefore, the associated probe is enabled), and that probe is
  74  * then disabled, ownership of that tracepoint may be exchanged for an
  75  * unused tracepoint belonging to another probe that was attached to the
  76  * enabled tracepoint.
  77  */
  78
  79 /*
  80  * APPLE NOTE: All kmutex_t's have been converted to lck_mtx_t
  81  */
  82
  83 typedef struct fasttrap_proc {
  84         pid_t ftpc_pid;                         /* process ID for this proc */
  85         uint64_t ftpc_acount;                   /* count of active providers */
  86         uint64_t ftpc_rcount;                   /* count of extant providers */
  87         lck_mtx_t ftpc_mtx;                     /* lock on all but acount */
  88         struct fasttrap_proc *ftpc_next;        /* next proc in hash chain */
  89 } fasttrap_proc_t;
  90
  91 typedef struct fasttrap_provider {
  92         pid_t ftp_pid;                          /* process ID for this prov */
  93         fasttrap_provider_type_t ftp_provider_type;     /* type of this provider (usdt, pid, objc, oneshot) */
  94         char ftp_name[DTRACE_PROVNAMELEN];      /* prov name (w/o the pid) */
  95         dtrace_provider_id_t ftp_provid;        /* DTrace provider handle */
  96         uint_t ftp_marked;                      /* mark for possible removal */
  97         uint_t ftp_retired;                     /* mark when retired */
  98         lck_mtx_t ftp_mtx;                      /* provider lock */
  99         lck_mtx_t ftp_cmtx;                     /* lock on creating probes */
 100         uint64_t ftp_rcount;                    /* enabled probes ref count */
 101         uint64_t ftp_ccount;                    /* consumers creating probes */
 102         uint64_t ftp_mcount;                    /* meta provider count */
 103         fasttrap_proc_t *ftp_proc;              /* shared proc for all provs */
 104         struct fasttrap_provider *ftp_next;     /* next prov in hash chain */
 105 } fasttrap_provider_t;
 106
 107 typedef struct fasttrap_id fasttrap_id_t;
 108 typedef struct fasttrap_probe fasttrap_probe_t;
 109 typedef struct fasttrap_tracepoint fasttrap_tracepoint_t;
 110
 111 struct fasttrap_id {
 112         fasttrap_probe_t *fti_probe;            /* referrring probe */
 113         fasttrap_id_t *fti_next;                /* enabled probe list on tp */
 114         fasttrap_probe_type_t fti_ptype;        /* probe type */
 115 };
 116
 117 typedef struct fasttrap_id_tp {
 118         fasttrap_id_t fit_id;
 119         fasttrap_tracepoint_t *fit_tp;
 120 } fasttrap_id_tp_t;
 121
 122 struct fasttrap_probe {
 123         dtrace_id_t ftp_id;                     /* DTrace probe identifier */
 124         pid_t ftp_pid;                          /* pid for this probe */
 125         fasttrap_provider_t *ftp_prov;          /* this probe's provider */
 126         user_addr_t ftp_faddr;                  /* associated function's addr */
 127         size_t ftp_fsize;                       /* associated function's size */
 128         uint64_t ftp_gen;                       /* modification generation */
 129         uint64_t ftp_ntps;                      /* number of tracepoints */
 130         uint8_t *ftp_argmap;                    /* native to translated args */
 131         uint8_t ftp_nargs;                      /* translated argument count */
 132         uint8_t ftp_enabled;                    /* is this probe enabled */
 133         char *ftp_xtypes;                       /* translated types index */
 134         char *ftp_ntypes;                       /* native types index */
 135         fasttrap_id_tp_t ftp_tps[1];            /* flexible array */
 136 };
 137
 138 #define FASTTRAP_ID_INDEX(id)   \
 139 ((fasttrap_id_tp_t *)(((char *)(id) - offsetof(fasttrap_id_tp_t, fit_id))) - \
 140 &(id)->fti_probe->ftp_tps[0])
 141
 142 struct fasttrap_tracepoint {
 143         fasttrap_proc_t *ftt_proc;              /* associated process struct */
 144         user_addr_t ftt_pc;                     /* address of tracepoint */
 145         pid_t ftt_pid;                          /* pid of tracepoint */
 146         fasttrap_machtp_t ftt_mtp;              /* ISA-specific portion */
 147         fasttrap_id_t *ftt_ids;                 /* NULL-terminated list */
 148         fasttrap_id_t *ftt_retids;              /* NULL-terminated list */
 149         fasttrap_tracepoint_t *ftt_next;        /* link in global hash */
 150 };
 151
 152 typedef struct fasttrap_bucket {
 153         lck_mtx_t ftb_mtx;                      /* bucket lock */
 154         void *ftb_data;                         /* data payload */
 155
 156         uint8_t ftb_pad[64 - sizeof (lck_mtx_t) - sizeof (void *)];
 157 } fasttrap_bucket_t;
 158
 159 typedef struct fasttrap_hash {
 160         ulong_t fth_nent;                       /* power-of-2 num. of entries */
 161         ulong_t fth_mask;                       /* fth_nent - 1 */
 162         fasttrap_bucket_t *fth_table;           /* array of buckets */
 163 } fasttrap_hash_t;
 164
 165 /*
 166  * If at some future point these assembly functions become observable by
 167  * DTrace, then these defines should become separate functions so that the
 168  * fasttrap provider doesn't trigger probes during internal operations.
 169  */
 170 #define fasttrap_copyout        copyout
 171 #define fasttrap_fuword32       fuword32
 172 #define fasttrap_suword32       suword32
 173
 174 /*
 175  * APPLE NOTE: xnu supports both 32bit and 64bit user processes.
 176  * We need to make size explicit.
 177  */
 178 #define fasttrap_fuword64       fuword64
 179 #define fasttrap_suword64       suword64
 180 #define fasttrap_fuword64_noerr fuword64_noerr
 181 #define fasttrap_fuword32_noerr fuword32_noerr
 182
 183 extern void fasttrap_sigtrap(proc_t *, uthread_t, user_addr_t);
 184
 185 extern dtrace_id_t              fasttrap_probe_id;
 186 extern fasttrap_hash_t          fasttrap_tpoints;
 187
 188 #define FASTTRAP_TPOINTS_INDEX(pid, pc) \
 189         (((pc) / sizeof (fasttrap_instr_t) + (pid)) & fasttrap_tpoints.fth_mask)
 190
 191 /*
 192  * Must be implemented by fasttrap_isa.c
 193  */
 194 extern int fasttrap_tracepoint_init(proc_t *, fasttrap_tracepoint_t *,
 195     user_addr_t, fasttrap_probe_type_t);
 196 extern int fasttrap_tracepoint_install(proc_t *, fasttrap_tracepoint_t *);
 197 extern int fasttrap_tracepoint_remove(proc_t *, fasttrap_tracepoint_t *);
 198
 199 #if defined(__x86_64__)
 200 extern int fasttrap_pid_probe(x86_saved_state_t *regs);
 201 extern int fasttrap_return_probe(x86_saved_state_t* regs);
 202 #else
 203 #error architecture not supported
 204 #endif
 205
 206 extern uint64_t fasttrap_pid_getarg(void *, dtrace_id_t, void *, int, int);
 207 extern uint64_t fasttrap_usdt_getarg(void *, dtrace_id_t, void *, int, int);
 208
 209 #ifdef  __cplusplus
 210 }
 211 #endif
 212
 213 #undef proc_t
 214
 215 #endif  /* _FASTTRAP_IMPL_H */