FreeBSD/Linux Kernel Cross Reference
sys/cddl/dev/systrace/systrace.c

     /*
      * 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
     *
     * Portions Copyright 2006-2008 John Birrell jb@freebsd.org
     */
    
    /*
     * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
     * Use is subject to license terms.
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD$");
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/conf.h>
    #include <sys/cpuvar.h>
    #include <sys/dtrace.h>
    #include <sys/fcntl.h>
    #include <sys/filio.h>
    #include <sys/kdb.h>
    #include <sys/kernel.h>
    #include <sys/kmem.h>
    #include <sys/kthread.h>
    #include <sys/limits.h>
    #include <sys/linker.h>
    #include <sys/lock.h>
    #include <sys/malloc.h>
    #include <sys/module.h>
    #include <sys/mutex.h>
    #include <sys/poll.h>
    #include <sys/proc.h>
    #include <sys/selinfo.h>
    #include <sys/smp.h>
    #include <sys/sysent.h>
    #include <sys/sysproto.h>
    #include <sys/uio.h>
    #include <sys/unistd.h>
    
    #include <cddl/dev/dtrace/dtrace_cddl.h>
    
    #include <machine/stdarg.h>
    
    #ifdef LINUX_SYSTRACE
    #if defined(__amd64__)
    #include <amd64/linux/linux.h>
    #include <amd64/linux/linux_proto.h>
    #include <amd64/linux/linux_syscalls.c>
    #include <amd64/linux/linux_systrace_args.c>
    #elif defined(__i386__)
    #include <i386/linux/linux.h>
    #include <i386/linux/linux_proto.h>
    #include <i386/linux/linux_syscalls.c>
    #include <i386/linux/linux_systrace_args.c>
    #else
    #error Only i386 and amd64 are supported.
    #endif
    #define MODNAME         "linux"
    extern struct sysent linux_sysent[];
    #define MAXSYSCALL      LINUX_SYS_MAXSYSCALL
    #define SYSCALLNAMES    linux_syscallnames
    #define SYSENT          linux_sysent
    #elif defined(LINUX32_SYSTRACE)
    #if defined(__amd64__)
    #include <amd64/linux32/linux.h>
    #include <amd64/linux32/linux32_proto.h>
    #include <amd64/linux32/linux32_syscalls.c>
    #include <amd64/linux32/linux32_systrace_args.c>
    #else
    #error Only amd64 is supported.
    #endif
    #define MODNAME         "linux32"
    extern struct sysent linux32_sysent[];
    #define MAXSYSCALL      LINUX32_SYS_MAXSYSCALL
    #define SYSCALLNAMES    linux32_syscallnames
    #define SYSENT          linux32_sysent
    #elif defined(FREEBSD32_SYSTRACE)
    /*
     * The syscall arguments are processed into a DTrace argument array
     * using a generated function. See sys/tools/makesyscalls.lua.
     */
   #include <compat/freebsd32/freebsd32_proto.h>
   #include <compat/freebsd32/freebsd32_util.h>
   #include <compat/freebsd32/freebsd32_syscall.h>
   #include <compat/freebsd32/freebsd32_systrace_args.c>
   extern const char *freebsd32_syscallnames[];
   #define MODNAME         "freebsd32"
   #define MAXSYSCALL      FREEBSD32_SYS_MAXSYSCALL
   #define SYSCALLNAMES    freebsd32_syscallnames
   #define SYSENT          freebsd32_sysent
   #else
   /*
    * The syscall arguments are processed into a DTrace argument array
    * using a generated function. See sys/tools/makesyscalls.lua.
    */
   #include <sys/syscall.h>
   #include <kern/systrace_args.c>
   #define MODNAME         "freebsd"
   #define MAXSYSCALL      SYS_MAXSYSCALL
   #define SYSCALLNAMES    syscallnames
   #define SYSENT          sysent
   #define NATIVE_ABI
   #endif
   
   #define PROVNAME        "syscall"
   #define DEVNAME         "dtrace/systrace/" MODNAME
   
   #define SYSTRACE_ARTIFICIAL_FRAMES      1
   
   #define SYSTRACE_SHIFT                  16
   #define SYSTRACE_ISENTRY(x)             ((int)(x) >> SYSTRACE_SHIFT)
   #define SYSTRACE_SYSNUM(x)              ((int)(x) & ((1 << SYSTRACE_SHIFT) - 1))
   #define SYSTRACE_ENTRY(id)              ((1 << SYSTRACE_SHIFT) | (id))
   #define SYSTRACE_RETURN(id)             (id)
   
   #if ((1 << SYSTRACE_SHIFT) <= MAXSYSCALL)
   #error 1 << SYSTRACE_SHIFT must exceed number of system calls
   #endif
   
   static int systrace_enabled_count;
   
   static void     systrace_load(void *);
   static void     systrace_unload(void *);
   
   static void     systrace_getargdesc(void *, dtrace_id_t, void *,
                       dtrace_argdesc_t *);
   static uint64_t systrace_getargval(void *, dtrace_id_t, void *, int, int);
   static void     systrace_provide(void *, dtrace_probedesc_t *);
   static void     systrace_destroy(void *, dtrace_id_t, void *);
   static void     systrace_enable(void *, dtrace_id_t, void *);
   static void     systrace_disable(void *, dtrace_id_t, void *);
   
   static union {
           const char      **p_constnames;
           char            **pp_syscallnames;
   } uglyhack = { SYSCALLNAMES };
   
   static dtrace_pattr_t systrace_attr = {
   { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
   { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
   { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA },
   { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
   { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA },
   };
   
   static dtrace_pops_t systrace_pops = {
           .dtps_provide =         systrace_provide,
           .dtps_provide_module =  NULL,
           .dtps_enable =          systrace_enable,
           .dtps_disable =         systrace_disable,
           .dtps_suspend =         NULL,
           .dtps_resume =          NULL,
           .dtps_getargdesc =      systrace_getargdesc,
           .dtps_getargval =       systrace_getargval,
           .dtps_usermode =        NULL,
           .dtps_destroy =         systrace_destroy
   };
   
   static dtrace_provider_id_t     systrace_id;
   
   #ifdef NATIVE_ABI
   /*
    * Probe callback function.
    *
    * Note: This function is called for _all_ syscalls, regardless of which sysent
    *       array the syscall comes from. It could be a standard syscall or a
    *       compat syscall from something like Linux.
    */
   static void
   systrace_probe(struct syscall_args *sa, enum systrace_probe_t type, int retval)
   {
           uint64_t uargs[nitems(sa->args)];
           dtrace_id_t id;
           int n_args, sysnum;
   
           sysnum = sa->code;
           memset(uargs, 0, sizeof(uargs));
   
           if (type == SYSTRACE_ENTRY) {
                   if ((id = sa->callp->sy_entry) == DTRACE_IDNONE)
                           return;
   
                   if (sa->callp->sy_systrace_args_func != NULL)
                           /*
                            * Convert the syscall parameters using the registered
                            * function.
                            */
                           (*sa->callp->sy_systrace_args_func)(sysnum, sa->args,
                               uargs, &n_args);
                   else
                           /*
                            * Use the built-in system call argument conversion
                            * function to translate the syscall structure fields
                            * into the array of 64-bit values that DTrace expects.
                            */
                           systrace_args(sysnum, sa->args, uargs, &n_args);
                   /*
                    * Save probe arguments now so that we can retrieve them if
                    * the getargval method is called from further down the stack.
                    */
                   curthread->t_dtrace_systrace_args = uargs;
           } else {
                   if ((id = sa->callp->sy_return) == DTRACE_IDNONE)
                           return;
   
                   curthread->t_dtrace_systrace_args = NULL;
                   /* Set arg0 and arg1 as the return value of this syscall. */
                   uargs[0] = uargs[1] = retval;
           }
   
           /* Process the probe using the converted argments. */
           dtrace_probe(id, uargs[0], uargs[1], uargs[2], uargs[3], uargs[4]);
   }
   #endif
   
   static void
   systrace_getargdesc(void *arg, dtrace_id_t id, void *parg,
       dtrace_argdesc_t *desc)
   {
           int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg);
   
           if (SYSTRACE_ISENTRY((uintptr_t)parg))
                   systrace_entry_setargdesc(sysnum, desc->dtargd_ndx,
                       desc->dtargd_native, sizeof(desc->dtargd_native));
           else
                   systrace_return_setargdesc(sysnum, desc->dtargd_ndx,
                       desc->dtargd_native, sizeof(desc->dtargd_native));
   
           if (desc->dtargd_native[0] == '\0')
                   desc->dtargd_ndx = DTRACE_ARGNONE;
   }
   
   static uint64_t
   systrace_getargval(void *arg __unused, dtrace_id_t id __unused,
       void *parg __unused, int argno, int aframes __unused)
   {
           uint64_t *uargs;
   
           uargs = curthread->t_dtrace_systrace_args;
           if (uargs == NULL)
                   /* This is a return probe. */
                   return (0);
           if (argno >= nitems(((struct syscall_args *)NULL)->args))
                   return (0);
           return (uargs[argno]);
   }
   
   static void
   systrace_provide(void *arg, dtrace_probedesc_t *desc)
   {
           int i;
   
           if (desc != NULL)
                   return;
   
           for (i = 0; i < MAXSYSCALL; i++) {
                   if (dtrace_probe_lookup(systrace_id, MODNAME,
                       uglyhack.pp_syscallnames[i], "entry") != 0)
                           continue;
   
                   (void)dtrace_probe_create(systrace_id, MODNAME,
                       uglyhack.pp_syscallnames[i], "entry",
                       SYSTRACE_ARTIFICIAL_FRAMES,
                       (void *)((uintptr_t)SYSTRACE_ENTRY(i)));
                   (void)dtrace_probe_create(systrace_id, MODNAME,
                       uglyhack.pp_syscallnames[i], "return",
                       SYSTRACE_ARTIFICIAL_FRAMES,
                       (void *)((uintptr_t)SYSTRACE_RETURN(i)));
           }
   }
   
   static void
   systrace_destroy(void *arg, dtrace_id_t id, void *parg)
   {
   #ifdef SYSTRACE_DEBUG
           int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg);
   
           /*
            * There's nothing to do here but assert that we have actually been
            * disabled.
            */
           if (SYSTRACE_ISENTRY((uintptr_t)parg)) {
                   ASSERT(sysent[sysnum].sy_entry == DTRACE_IDNONE);
           } else {
                   ASSERT(sysent[sysnum].sy_return == DTRACE_IDNONE);
           }
   #endif
   }
   
   static void
   systrace_enable(void *arg, dtrace_id_t id, void *parg)
   {
           int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg);
   
           SYSENT[sysnum].sy_systrace_args_func = systrace_args;
   
           if (SYSTRACE_ISENTRY((uintptr_t)parg))
                   SYSENT[sysnum].sy_entry = id;
           else
                   SYSENT[sysnum].sy_return = id;
           systrace_enabled_count++;
           if (systrace_enabled_count == 1)
                   systrace_enabled = true;
   }
   
   static void
   systrace_disable(void *arg, dtrace_id_t id, void *parg)
   {
           int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg);
   
           SYSENT[sysnum].sy_systrace_args_func = NULL;
           SYSENT[sysnum].sy_entry = DTRACE_IDNONE;
           SYSENT[sysnum].sy_return = DTRACE_IDNONE;
           systrace_enabled_count--;
           if (systrace_enabled_count == 0)
                   systrace_enabled = false;
   }
   
   static void
   systrace_load(void *dummy __unused)
   {
   
           if (dtrace_register(PROVNAME, &systrace_attr, DTRACE_PRIV_USER, NULL,
               &systrace_pops, NULL, &systrace_id) != 0)
                   return;
   
   #ifdef NATIVE_ABI
           systrace_probe_func = systrace_probe;
   #endif
   }
   
   static void
   systrace_unload(void *dummy __unused)
   {
   
   #ifdef NATIVE_ABI
           systrace_probe_func = NULL;
   #endif
   
           if (dtrace_unregister(systrace_id) != 0)
                   return;
   }
   
   static int
   systrace_modevent(module_t mod __unused, int type, void *data __unused)
   {
           int error;
   
           error = 0;
           switch (type) {
           case MOD_LOAD:
                   break;
   
           case MOD_UNLOAD:
                   break;
   
           case MOD_SHUTDOWN:
                   break;
   
           default:
                   error = EOPNOTSUPP;
                   break;
   
           }
           return (error);
   }
   
   SYSINIT(systrace_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY,
       systrace_load, NULL);
   SYSUNINIT(systrace_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY,
       systrace_unload, NULL);
   
   #ifdef LINUX_SYSTRACE
   DEV_MODULE(systrace_linux, systrace_modevent, NULL);
   MODULE_VERSION(systrace_linux, 1);
   #ifdef __amd64__
   MODULE_DEPEND(systrace_linux, linux64, 1, 1, 1);
   #else
   MODULE_DEPEND(systrace_linux, linux, 1, 1, 1);
   #endif
   MODULE_DEPEND(systrace_linux, dtrace, 1, 1, 1);
   MODULE_DEPEND(systrace_linux, opensolaris, 1, 1, 1);
   #elif defined(LINUX32_SYSTRACE)
   DEV_MODULE(systrace_linux32, systrace_modevent, NULL);
   MODULE_VERSION(systrace_linux32, 1);
   MODULE_DEPEND(systrace_linux32, linux, 1, 1, 1);
   MODULE_DEPEND(systrace_linux32, dtrace, 1, 1, 1);
   MODULE_DEPEND(systrace_linux32, opensolaris, 1, 1, 1);
   #elif defined(FREEBSD32_SYSTRACE)
   DEV_MODULE(systrace_freebsd32, systrace_modevent, NULL);
   MODULE_VERSION(systrace_freebsd32, 1);
   MODULE_DEPEND(systrace_freebsd32, dtrace, 1, 1, 1);
   MODULE_DEPEND(systrace_freebsd32, opensolaris, 1, 1, 1);
   #else
   DEV_MODULE(systrace, systrace_modevent, NULL);
   MODULE_VERSION(systrace, 1);
   MODULE_DEPEND(systrace, dtrace, 1, 1, 1);
   MODULE_DEPEND(systrace, opensolaris, 1, 1, 1);
   #endif

Cache object: 06548ea59c1d09de79a17ac3eb9a97a4