[apple/xnu.git] / bsd / dev / dtrace / fbt.c

/*
 * 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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/* #pragma ident	"@(#)fbt.c	1.15	05/09/19 SMI" */

#ifdef KERNEL
#ifndef _KERNEL
#define _KERNEL /* Solaris vs. Darwin */
#endif
#endif

#include <mach-o/loader.h> 
#include <kern/mach_header.h>

extern struct mach_header _mh_execute_header; /* the kernel's mach header */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <miscfs/devfs/devfs.h>
#include <pexpert/pexpert.h>

#include <sys/dtrace.h>
#include <sys/dtrace_impl.h>
#include <sys/fbt.h>

#include <sys/dtrace_glue.h>

/* #include <machine/trap.h> */
struct savearea_t; /* Used anonymously */
typedef kern_return_t (*perfCallback)(int, struct savearea_t *, int, int);

#if defined (__ppc__) || defined (__ppc64__)
extern perfCallback tempDTraceTrapHook, tempDTraceIntHook;
extern kern_return_t fbt_perfCallback(int, struct savearea_t *, int, int);
extern kern_return_t fbt_perfIntCallback(int, struct savearea_t *, int, int);
#else
extern perfCallback tempDTraceTrapHook;
extern kern_return_t fbt_perfCallback(int, struct savearea_t *, int, int);
#endif

#define	FBT_ADDR2NDX(addr)	((((uintptr_t)(addr)) >> 4) & fbt_probetab_mask)
#define	FBT_PROBETAB_SIZE	0x8000		/* 32k entries -- 128K total */

static dev_info_t		*fbt_devi;
static int				fbt_probetab_size;
dtrace_provider_id_t	fbt_id;
fbt_probe_t				**fbt_probetab;
int						fbt_probetab_mask;
static int				fbt_verbose = 0;

void fbt_init( void );

/*ARGSUSED*/
static void
fbt_destroy(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg,id)
	fbt_probe_t *fbt = parg, *next, *hash, *last;
	int ndx;

	do {
		/*
		 * Now we need to remove this probe from the fbt_probetab.
		 */
		ndx = FBT_ADDR2NDX(fbt->fbtp_patchpoint);
		last = NULL;
		hash = fbt_probetab[ndx];

		while (hash != fbt) {
			ASSERT(hash != NULL);
			last = hash;
			hash = hash->fbtp_hashnext;
		}

		if (last != NULL) {
			last->fbtp_hashnext = fbt->fbtp_hashnext;
		} else {
			fbt_probetab[ndx] = fbt->fbtp_hashnext;
		}

		next = fbt->fbtp_next;
		kmem_free(fbt, sizeof (fbt_probe_t));

		fbt = next;
	} while (fbt != NULL);
}

/*ARGSUSED*/
static void
fbt_enable(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg,id)
	fbt_probe_t *fbt = parg;
	struct modctl *ctl = fbt->fbtp_ctl;

#if defined (__ppc__) || defined (__ppc64__)
	dtrace_casptr(&tempDTraceIntHook, NULL, fbt_perfIntCallback);
	if (tempDTraceIntHook != (perfCallback)fbt_perfIntCallback) {
		if (fbt_verbose) {
			cmn_err(CE_NOTE, "fbt_enable is failing for probe %s "
			    "in module %s: tempDTraceIntHook already occupied.",
			    fbt->fbtp_name, ctl->mod_modname);
		}
		return;
	}
#endif
	
	dtrace_casptr(&tempDTraceTrapHook, NULL, fbt_perfCallback);
	if (tempDTraceTrapHook != (perfCallback)fbt_perfCallback) {
		if (fbt_verbose) {
			cmn_err(CE_NOTE, "fbt_enable is failing for probe %s "
			    "in module %s: tempDTraceTrapHook already occupied.",
			    fbt->fbtp_name, ctl->mod_modname);
		}
		return;
	}

	for (; fbt != NULL; fbt = fbt->fbtp_next)
		(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_patchval, (vm_offset_t)fbt->fbtp_patchpoint, 
								sizeof(fbt->fbtp_patchval));
		
	dtrace_membar_consumer();
}

/*ARGSUSED*/
static void
fbt_disable(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg,id)
	fbt_probe_t *fbt = parg;

	for (; fbt != NULL; fbt = fbt->fbtp_next)
		(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_savedval, (vm_offset_t)fbt->fbtp_patchpoint, 
								sizeof(fbt->fbtp_savedval));
		
	dtrace_membar_consumer();
}

/*ARGSUSED*/
static void
fbt_suspend(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg,id)
	fbt_probe_t *fbt = parg;

	for (; fbt != NULL; fbt = fbt->fbtp_next)
		(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_savedval, (vm_offset_t)fbt->fbtp_patchpoint, 
								sizeof(fbt->fbtp_savedval));
		
	dtrace_membar_consumer();
}

/*ARGSUSED*/
static void
fbt_resume(void *arg, dtrace_id_t id, void *parg)
{
#pragma unused(arg,id)
	fbt_probe_t *fbt = parg;
	struct modctl *ctl = fbt->fbtp_ctl;

#if defined (__ppc__) || defined (__ppc64__)
	dtrace_casptr(&tempDTraceIntHook, NULL, fbt_perfIntCallback);
	if (tempDTraceIntHook != (perfCallback)fbt_perfIntCallback) {
		if (fbt_verbose) {
			cmn_err(CE_NOTE, "fbt_enable is failing for probe %s "
			    "in module %s: tempDTraceIntHook already occupied.",
			    fbt->fbtp_name, ctl->mod_modname);
		}
		return;
	}
#endif
	
	dtrace_casptr(&tempDTraceTrapHook, NULL, fbt_perfCallback);
	if (tempDTraceTrapHook != (perfCallback)fbt_perfCallback) {
		if (fbt_verbose) {
			cmn_err(CE_NOTE, "fbt_resume is failing for probe %s "
			    "in module %s: tempDTraceTrapHook already occupied.",
			    fbt->fbtp_name, ctl->mod_modname);
		}
		return;
	}
	
	for (; fbt != NULL; fbt = fbt->fbtp_next)
		(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_patchval, (vm_offset_t)fbt->fbtp_patchpoint, 
								sizeof(fbt->fbtp_patchval));
		
	dtrace_membar_consumer();
}

#if !defined(__APPLE__)
/*ARGSUSED*/
static void
fbt_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc)
{
	fbt_probe_t *fbt = parg;
	struct modctl *ctl = fbt->fbtp_ctl;
	struct module *mp = ctl->mod_mp;
	ctf_file_t *fp = NULL, *pfp;
	ctf_funcinfo_t f;
	int error;
	ctf_id_t argv[32], type;
	int argc = sizeof (argv) / sizeof (ctf_id_t);
	const char *parent;

	if (!ctl->mod_loaded || (ctl->mod_loadcnt != fbt->fbtp_loadcnt))
		goto err;

	if (fbt->fbtp_roffset != 0 && desc->dtargd_ndx == 0) {
		(void) strlcpy(desc->dtargd_native, "int",
			       sizeof(desc->dtargd_native));
		return;
	}

	if ((fp = ctf_modopen(mp, &error)) == NULL) {
		/*
		 * We have no CTF information for this module -- and therefore
		 * no args[] information.
		 */
		goto err;
	}

	/*
	 * If we have a parent container, we must manually import it.
	 */
	if ((parent = ctf_parent_name(fp)) != NULL) {
		struct modctl *mod;

		/*
		 * We must iterate over all modules to find the module that
		 * is our parent.
		 */
		for (mod = &modules; mod != NULL; mod = mod->mod_next) {
			if (strcmp(mod->mod_filename, parent) == 0)
				break;
		}

		if (mod == NULL)
			goto err;

		if ((pfp = ctf_modopen(mod->mod_mp, &error)) == NULL)
			goto err;

		if (ctf_import(fp, pfp) != 0) {
			ctf_close(pfp);
			goto err;
		}

		ctf_close(pfp);
	}

	if (ctf_func_info(fp, fbt->fbtp_symndx, &f) == CTF_ERR)
		goto err;

	if (fbt->fbtp_roffset != 0) {
		if (desc->dtargd_ndx > 1)
			goto err;

		ASSERT(desc->dtargd_ndx == 1);
		type = f.ctc_return;
	} else {
		if (desc->dtargd_ndx + 1 > f.ctc_argc)
			goto err;

		if (ctf_func_args(fp, fbt->fbtp_symndx, argc, argv) == CTF_ERR)
			goto err;

		type = argv[desc->dtargd_ndx];
	}

	if (ctf_type_name(fp, type, desc->dtargd_native,
	    DTRACE_ARGTYPELEN) != NULL) {
		ctf_close(fp);
		return;
	}
err:
	if (fp != NULL)
		ctf_close(fp);

	desc->dtargd_ndx = DTRACE_ARGNONE;
}
#endif /* __APPLE__ */

static dtrace_pattr_t fbt_attr = {
{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA },
{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA },
{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA },
};

static dtrace_pops_t fbt_pops = {
	NULL,
	fbt_provide_module,
	fbt_enable,
	fbt_disable,
	fbt_suspend,
	fbt_resume,
#if !defined(__APPLE__)
	fbt_getargdesc,
#else
	NULL, /* XXX where to look for xnu? */
#endif /* __APPLE__ */
	NULL,
	NULL,
	fbt_destroy
};

static void
fbt_cleanup(dev_info_t *devi)
{
	dtrace_invop_remove(fbt_invop);
	ddi_remove_minor_node(devi, NULL);
	kmem_free(fbt_probetab, fbt_probetab_size * sizeof (fbt_probe_t *));
	fbt_probetab = NULL;
	fbt_probetab_mask = 0;
}

static int
fbt_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
{
	switch (cmd) {
	case DDI_ATTACH:
		break;
	case DDI_RESUME:
		return (DDI_SUCCESS);
	default:
		return (DDI_FAILURE);
	}

	if (fbt_probetab_size == 0)
		fbt_probetab_size = FBT_PROBETAB_SIZE;

	fbt_probetab_mask = fbt_probetab_size - 1;
	fbt_probetab =
	    kmem_zalloc(fbt_probetab_size * sizeof (fbt_probe_t *), KM_SLEEP);

	dtrace_invop_add(fbt_invop);

	if (ddi_create_minor_node(devi, "fbt", S_IFCHR, 0,
	    DDI_PSEUDO, NULL) == DDI_FAILURE ||
	    dtrace_register("fbt", &fbt_attr, DTRACE_PRIV_KERNEL, NULL,
	    &fbt_pops, NULL, &fbt_id) != 0) {
		fbt_cleanup(devi);
		return (DDI_FAILURE);
	}

	ddi_report_dev(devi);
	fbt_devi = devi;

	return (DDI_SUCCESS);
}

static d_open_t _fbt_open;

static int
_fbt_open(dev_t dev, int flags, int devtype, struct proc *p)
{
#pragma unused(dev,flags,devtype,p)
	return 0;
}

#define FBT_MAJOR  -24 /* let the kernel pick the device number */

/*
 * A struct describing which functions will get invoked for certain
 * actions.
 */
static struct cdevsw fbt_cdevsw =
{
	_fbt_open,		/* open */
	eno_opcl,			/* close */
	eno_rdwrt,			/* read */
	eno_rdwrt,			/* write */
	eno_ioctl,			/* ioctl */
	(stop_fcn_t *)nulldev, /* stop */
	(reset_fcn_t *)nulldev, /* reset */
	NULL,				/* tty's */
	eno_select,			/* select */
	eno_mmap,			/* mmap */
	eno_strat,			/* strategy */
	eno_getc,			/* getc */
	eno_putc,			/* putc */
	0					/* type */
};

static int gDisableFBT = 0;
struct modctl g_fbt_kernctl;
#undef kmem_alloc /* from its binding to dt_kmem_alloc glue */
#undef kmem_free /* from its binding to dt_kmem_free glue */
#include <vm/vm_kern.h>

void
fbt_init( void )
{

	PE_parse_boot_arg("DisableFBT", &gDisableFBT);

	if (0 == gDisableFBT)
	{
		int majdevno = cdevsw_add(FBT_MAJOR, &fbt_cdevsw);
		int size = 0, header_size, round_size;
	   	kern_return_t ret;
		void *p, *q;
		
		if (majdevno < 0) {
			printf("fbt_init: failed to allocate a major number!\n");
			return;
		}

		/*
		 * Capture the kernel's mach_header in its entirety and the contents of
		 * its LINKEDIT segment (and only that segment). This is sufficient to
		 * build all the fbt probes lazily the first time a client looks to
		 * the fbt provider. Remeber thes on the global struct modctl g_fbt_kernctl.
		 */
		header_size = sizeof(struct mach_header) + _mh_execute_header.sizeofcmds;
		p = getsegdatafromheader(&_mh_execute_header, SEG_LINKEDIT, &size);

        round_size = round_page_32(header_size + size);
		ret = kmem_alloc_pageable(kernel_map, (vm_offset_t *)&q, round_size);

		if (p && (ret == KERN_SUCCESS)) {
			struct segment_command *sgp;

			bcopy( (void *)&_mh_execute_header, q, header_size);
			bcopy( p, (char *)q + header_size, size);

			sgp = getsegbynamefromheader(q, SEG_LINKEDIT);

			if (sgp) {
				sgp->vmaddr = (unsigned long)((char *)q + header_size);
				g_fbt_kernctl.address = (vm_address_t)q;
				g_fbt_kernctl.size = header_size + size;
			} else {
				kmem_free(kernel_map, (vm_offset_t)q, round_size);
				g_fbt_kernctl.address = (vm_address_t)NULL;
				g_fbt_kernctl.size = 0;
			}
		} else {
			if (ret == KERN_SUCCESS)
				kmem_free(kernel_map, (vm_offset_t)q, round_size);
			g_fbt_kernctl.address = (vm_address_t)NULL;
			g_fbt_kernctl.size = 0;
		}

		strncpy((char *)&(g_fbt_kernctl.mod_modname), "mach_kernel", KMOD_MAX_NAME);

		fbt_attach( (dev_info_t	*)majdevno, DDI_ATTACH );

		gDisableFBT = 1; /* Ensure this initialization occurs just one time. */
	}
	else
		printf("fbt_init: DisableFBT non-zero, no FBT probes will be provided.\n");
}
#undef FBT_MAJOR
Commit	Line	Data
2d21ac55 A	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, Version 1.0 only
	6	* (the "License"). You may not use this file except in compliance
	7	* with the License.
	8	*
	9	* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
	10	* or http://www.opensolaris.org/os/licensing.
	11	* See the License for the specific language governing permissions
	12	* and limitations under the License.
	13	*
	14	* When distributing Covered Code, include this CDDL HEADER in each
	15	* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
	16	* If applicable, add the following below this CDDL HEADER, with the
	17	* fields enclosed by brackets "[]" replaced with your own identifying
	18	* information: Portions Copyright [yyyy] [name of copyright owner]
	19	*
	20	* CDDL HEADER END
	21	*/
	22	/*
	23	* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
	24	* Use is subject to license terms.
	25	*/
	26
	27	/* #pragma ident "@(#)fbt.c 1.15 05/09/19 SMI" */
	28
	29	#ifdef KERNEL
	30	#ifndef _KERNEL
	31	#define _KERNEL /* Solaris vs. Darwin */
	32	#endif
	33	#endif
	34
	35	#include <mach-o/loader.h>
	36	#include <kern/mach_header.h>
	37
	38	extern struct mach_header _mh_execute_header; /* the kernel's mach header */
	39
	40	#include <sys/param.h>
	41	#include <sys/systm.h>
	42	#include <sys/errno.h>
	43	#include <sys/stat.h>
	44	#include <sys/ioctl.h>
	45	#include <sys/conf.h>
	46	#include <sys/fcntl.h>
	47	#include <miscfs/devfs/devfs.h>
	48	#include <pexpert/pexpert.h>
	49
	50	#include <sys/dtrace.h>
	51	#include <sys/dtrace_impl.h>
	52	#include <sys/fbt.h>
	53
	54	#include <sys/dtrace_glue.h>
	55
	56	/* #include <machine/trap.h> */
	57	struct savearea_t; /* Used anonymously */
	58	typedef kern_return_t (perfCallback)(int, struct savearea_t , int, int);
	59
	60	#if defined (__ppc__) \|\| defined (__ppc64__)
	61	extern perfCallback tempDTraceTrapHook, tempDTraceIntHook;
	62	extern kern_return_t fbt_perfCallback(int, struct savearea_t *, int, int);
	63	extern kern_return_t fbt_perfIntCallback(int, struct savearea_t *, int, int);
	64	#else
65	extern perfCallback tempDTraceTrapHook;
66	extern kern_return_t fbt_perfCallback(int, struct savearea_t *, int, int);
67	#endif
68
69	#define FBT_ADDR2NDX(addr) ((((uintptr_t)(addr)) >> 4) & fbt_probetab_mask)
70	#define FBT_PROBETAB_SIZE 0x8000 /* 32k entries -- 128K total */
71
72	static dev_info_t *fbt_devi;
73	static int fbt_probetab_size;
74	dtrace_provider_id_t fbt_id;
75	fbt_probe_t **fbt_probetab;
76	int fbt_probetab_mask;
77	static int fbt_verbose = 0;
78
79	void fbt_init( void );
80
81	/ARGSUSED/
82	static void
83	fbt_destroy(void arg, dtrace_id_t id, void parg)
84	{
85	#pragma unused(arg,id)
86	fbt_probe_t fbt = parg, next, hash, last;
87	int ndx;
88
89	do {
90	/*
91	* Now we need to remove this probe from the fbt_probetab.
92	*/
93	ndx = FBT_ADDR2NDX(fbt->fbtp_patchpoint);
94	last = NULL;
95	hash = fbt_probetab[ndx];
96
97	while (hash != fbt) {
98	ASSERT(hash != NULL);
99	last = hash;
100	hash = hash->fbtp_hashnext;
101	}
102
103	if (last != NULL) {
104	last->fbtp_hashnext = fbt->fbtp_hashnext;
105	} else {
106	fbt_probetab[ndx] = fbt->fbtp_hashnext;
107	}
108
109	next = fbt->fbtp_next;
110	kmem_free(fbt, sizeof (fbt_probe_t));
111
112	fbt = next;
113	} while (fbt != NULL);
114	}
115
116	/ARGSUSED/
117	static void
118	fbt_enable(void arg, dtrace_id_t id, void parg)
119	{
120	#pragma unused(arg,id)
121	fbt_probe_t *fbt = parg;
122	struct modctl *ctl = fbt->fbtp_ctl;
123
124	#if defined (__ppc__) \|\| defined (__ppc64__)
125	dtrace_casptr(&tempDTraceIntHook, NULL, fbt_perfIntCallback);
126	if (tempDTraceIntHook != (perfCallback)fbt_perfIntCallback) {
127	if (fbt_verbose) {
128	cmn_err(CE_NOTE, "fbt_enable is failing for probe %s "
129	"in module %s: tempDTraceIntHook already occupied.",
130	fbt->fbtp_name, ctl->mod_modname);
131	}
132	return;
133	}
134	#endif
135
136	dtrace_casptr(&tempDTraceTrapHook, NULL, fbt_perfCallback);
137	if (tempDTraceTrapHook != (perfCallback)fbt_perfCallback) {
138	if (fbt_verbose) {
139	cmn_err(CE_NOTE, "fbt_enable is failing for probe %s "
140	"in module %s: tempDTraceTrapHook already occupied.",
141	fbt->fbtp_name, ctl->mod_modname);
142	}
143	return;
144	}
145
146	for (; fbt != NULL; fbt = fbt->fbtp_next)
147	(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_patchval, (vm_offset_t)fbt->fbtp_patchpoint,
148	sizeof(fbt->fbtp_patchval));
149
150	dtrace_membar_consumer();
151	}
152
153	/ARGSUSED/
154	static void
155	fbt_disable(void arg, dtrace_id_t id, void parg)
156	{
157	#pragma unused(arg,id)
158	fbt_probe_t *fbt = parg;
159
160	for (; fbt != NULL; fbt = fbt->fbtp_next)
161	(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_savedval, (vm_offset_t)fbt->fbtp_patchpoint,
162	sizeof(fbt->fbtp_savedval));
163
164	dtrace_membar_consumer();
165	}
166
167	/ARGSUSED/
168	static void
169	fbt_suspend(void arg, dtrace_id_t id, void parg)
170	{
171	#pragma unused(arg,id)
172	fbt_probe_t *fbt = parg;
173
174	for (; fbt != NULL; fbt = fbt->fbtp_next)
175	(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_savedval, (vm_offset_t)fbt->fbtp_patchpoint,
176	sizeof(fbt->fbtp_savedval));
177
178	dtrace_membar_consumer();
179	}
180
181	/ARGSUSED/
182	static void
183	fbt_resume(void arg, dtrace_id_t id, void parg)
184	{
185	#pragma unused(arg,id)
186	fbt_probe_t *fbt = parg;
187	struct modctl *ctl = fbt->fbtp_ctl;
188
189	#if defined (__ppc__) \|\| defined (__ppc64__)
190	dtrace_casptr(&tempDTraceIntHook, NULL, fbt_perfIntCallback);
191	if (tempDTraceIntHook != (perfCallback)fbt_perfIntCallback) {
192	if (fbt_verbose) {
193	cmn_err(CE_NOTE, "fbt_enable is failing for probe %s "
194	"in module %s: tempDTraceIntHook already occupied.",
195	fbt->fbtp_name, ctl->mod_modname);
196	}
197	return;
198	}
199	#endif
200
201	dtrace_casptr(&tempDTraceTrapHook, NULL, fbt_perfCallback);
202	if (tempDTraceTrapHook != (perfCallback)fbt_perfCallback) {
203	if (fbt_verbose) {
204	cmn_err(CE_NOTE, "fbt_resume is failing for probe %s "
205	"in module %s: tempDTraceTrapHook already occupied.",
206	fbt->fbtp_name, ctl->mod_modname);
207	}
208	return;
209	}
210
211	for (; fbt != NULL; fbt = fbt->fbtp_next)
212	(void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_patchval, (vm_offset_t)fbt->fbtp_patchpoint,
213	sizeof(fbt->fbtp_patchval));
214
215	dtrace_membar_consumer();
216	}
217
218	#if !defined(__APPLE__)
219	/ARGSUSED/
220	static void
221	fbt_getargdesc(void arg, dtrace_id_t id, void parg, dtrace_argdesc_t *desc)
222	{
223	fbt_probe_t *fbt = parg;
224	struct modctl *ctl = fbt->fbtp_ctl;
225	struct module *mp = ctl->mod_mp;
226	ctf_file_t fp = NULL, pfp;
227	ctf_funcinfo_t f;
228	int error;
229	ctf_id_t argv[32], type;
230	int argc = sizeof (argv) / sizeof (ctf_id_t);
231	const char *parent;
232
233	if (!ctl->mod_loaded \|\| (ctl->mod_loadcnt != fbt->fbtp_loadcnt))
234	goto err;
235
236	if (fbt->fbtp_roffset != 0 && desc->dtargd_ndx == 0) {
237	(void) strlcpy(desc->dtargd_native, "int",
238	sizeof(desc->dtargd_native));
239	return;
240	}
241
242	if ((fp = ctf_modopen(mp, &error)) == NULL) {
243	/*
244	* We have no CTF information for this module -- and therefore
245	* no args[] information.
246	*/
247	goto err;
248	}
249
250	/*
251	* If we have a parent container, we must manually import it.
252	*/
253	if ((parent = ctf_parent_name(fp)) != NULL) {
254	struct modctl *mod;
255
256	/*
257	* We must iterate over all modules to find the module that
258	* is our parent.
259	*/
260	for (mod = &modules; mod != NULL; mod = mod->mod_next) {
261	if (strcmp(mod->mod_filename, parent) == 0)
262	break;
263	}
264
265	if (mod == NULL)
266	goto err;
267
268	if ((pfp = ctf_modopen(mod->mod_mp, &error)) == NULL)
269	goto err;
270
271	if (ctf_import(fp, pfp) != 0) {
272	ctf_close(pfp);
273	goto err;
274	}
275
276	ctf_close(pfp);
277	}
278
279	if (ctf_func_info(fp, fbt->fbtp_symndx, &f) == CTF_ERR)
280	goto err;
281
282	if (fbt->fbtp_roffset != 0) {
283	if (desc->dtargd_ndx > 1)
284	goto err;
285
286	ASSERT(desc->dtargd_ndx == 1);
287	type = f.ctc_return;
288	} else {
289	if (desc->dtargd_ndx + 1 > f.ctc_argc)
290	goto err;
291
292	if (ctf_func_args(fp, fbt->fbtp_symndx, argc, argv) == CTF_ERR)
293	goto err;
294
295	type = argv[desc->dtargd_ndx];
296	}
297
298	if (ctf_type_name(fp, type, desc->dtargd_native,
299	DTRACE_ARGTYPELEN) != NULL) {
300	ctf_close(fp);
301	return;
302	}
303	err:
304	if (fp != NULL)
305	ctf_close(fp);
306
307	desc->dtargd_ndx = DTRACE_ARGNONE;
308	}
309	#endif /* __APPLE__ */
310
311	static dtrace_pattr_t fbt_attr = {
312	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA },
313	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
314	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
315	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA },
316	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA },
317	};
318
319	static dtrace_pops_t fbt_pops = {
320	NULL,
321	fbt_provide_module,
322	fbt_enable,
323	fbt_disable,
324	fbt_suspend,
325	fbt_resume,
326	#if !defined(__APPLE__)
327	fbt_getargdesc,
328	#else
329	NULL, /* XXX where to look for xnu? */
330	#endif /* __APPLE__ */
331	NULL,
332	NULL,
333	fbt_destroy
334	};
335
336	static void
337	fbt_cleanup(dev_info_t *devi)
338	{
339	dtrace_invop_remove(fbt_invop);
340	ddi_remove_minor_node(devi, NULL);
341	kmem_free(fbt_probetab, fbt_probetab_size * sizeof (fbt_probe_t *));
342	fbt_probetab = NULL;
343	fbt_probetab_mask = 0;
344	}
345
346	static int
347	fbt_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
348	{
349	switch (cmd) {
350	case DDI_ATTACH:
351	break;
352	case DDI_RESUME:
353	return (DDI_SUCCESS);
354	default:
355	return (DDI_FAILURE);
356	}
357
358	if (fbt_probetab_size == 0)
359	fbt_probetab_size = FBT_PROBETAB_SIZE;
360
361	fbt_probetab_mask = fbt_probetab_size - 1;
362	fbt_probetab =
363	kmem_zalloc(fbt_probetab_size * sizeof (fbt_probe_t *), KM_SLEEP);
364
365	dtrace_invop_add(fbt_invop);
366
367	if (ddi_create_minor_node(devi, "fbt", S_IFCHR, 0,
368	DDI_PSEUDO, NULL) == DDI_FAILURE \|\|
369	dtrace_register("fbt", &fbt_attr, DTRACE_PRIV_KERNEL, NULL,
370	&fbt_pops, NULL, &fbt_id) != 0) {
371	fbt_cleanup(devi);
372	return (DDI_FAILURE);
373	}
374
375	ddi_report_dev(devi);
376	fbt_devi = devi;
377
378	return (DDI_SUCCESS);
379	}
380
381	static d_open_t _fbt_open;
382
383	static int
384	_fbt_open(dev_t dev, int flags, int devtype, struct proc *p)
385	{
386	#pragma unused(dev,flags,devtype,p)
387	return 0;
388	}
389
390	#define FBT_MAJOR -24 /* let the kernel pick the device number */
391
392	/*
393	* A struct describing which functions will get invoked for certain
394	* actions.
395	*/
396	static struct cdevsw fbt_cdevsw =
397	{
398	_fbt_open, /* open */
399	eno_opcl, /* close */
400	eno_rdwrt, /* read */
401	eno_rdwrt, /* write */
402	eno_ioctl, /* ioctl */
403	(stop_fcn_t )nulldev, / stop */
404	(reset_fcn_t )nulldev, / reset */
405	NULL, /* tty's */
406	eno_select, /* select */
407	eno_mmap, /* mmap */
408	eno_strat, /* strategy */
409	eno_getc, /* getc */
410	eno_putc, /* putc */
411	0 /* type */
412	};
413
414	static int gDisableFBT = 0;
415	struct modctl g_fbt_kernctl;
416	#undef kmem_alloc /* from its binding to dt_kmem_alloc glue */
417	#undef kmem_free /* from its binding to dt_kmem_free glue */
418	#include <vm/vm_kern.h>
419
420	void
421	fbt_init( void )
422	{
423
424	PE_parse_boot_arg("DisableFBT", &gDisableFBT);
425
426	if (0 == gDisableFBT)
427	{
428	int majdevno = cdevsw_add(FBT_MAJOR, &fbt_cdevsw);
429	int size = 0, header_size, round_size;
430	kern_return_t ret;
431	void p, q;
432
433	if (majdevno < 0) {
434	printf("fbt_init: failed to allocate a major number!\n");
435	return;
436	}
437
438	/*
439	* Capture the kernel's mach_header in its entirety and the contents of
440	* its LINKEDIT segment (and only that segment). This is sufficient to
441	* build all the fbt probes lazily the first time a client looks to
442	* the fbt provider. Remeber thes on the global struct modctl g_fbt_kernctl.
443	*/
444	header_size = sizeof(struct mach_header) + _mh_execute_header.sizeofcmds;
445	p = getsegdatafromheader(&_mh_execute_header, SEG_LINKEDIT, &size);
446
447	round_size = round_page_32(header_size + size);
448	ret = kmem_alloc_pageable(kernel_map, (vm_offset_t *)&q, round_size);
449
450	if (p && (ret == KERN_SUCCESS)) {
451	struct segment_command *sgp;
452
453	bcopy( (void *)&_mh_execute_header, q, header_size);
454	bcopy( p, (char *)q + header_size, size);
455
456	sgp = getsegbynamefromheader(q, SEG_LINKEDIT);
457
458	if (sgp) {
459	sgp->vmaddr = (unsigned long)((char *)q + header_size);
460	g_fbt_kernctl.address = (vm_address_t)q;
461	g_fbt_kernctl.size = header_size + size;
462	} else {
463	kmem_free(kernel_map, (vm_offset_t)q, round_size);
464	g_fbt_kernctl.address = (vm_address_t)NULL;
465	g_fbt_kernctl.size = 0;
466	}
467	} else {
468	if (ret == KERN_SUCCESS)
469	kmem_free(kernel_map, (vm_offset_t)q, round_size);
470	g_fbt_kernctl.address = (vm_address_t)NULL;
471	g_fbt_kernctl.size = 0;
472	}
473
474	strncpy((char *)&(g_fbt_kernctl.mod_modname), "mach_kernel", KMOD_MAX_NAME);
475
476	fbt_attach( (dev_info_t *)majdevno, DDI_ATTACH );
477
478	gDisableFBT = 1; /* Ensure this initialization occurs just one time. */
479	}
480	else
481	printf("fbt_init: DisableFBT non-zero, no FBT probes will be provided.\n");
482	}
483	#undef FBT_MAJOR