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      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 2005 Sun Microsystems, Inc.  All rights reserved.
     24  * Use is subject to license terms.
     25  */
     26 
     27 #pragma ident	"@(#)hat.c	1.8	05/12/08 SMI"
     28 
     29 #include <sys/param.h>
     30 #include <sys/kmem.h>
     31 #include <sys/sysmacros.h>
     32 #include <sys/cmn_err.h>
     33 #include <sys/systm.h>
     34 #include <sys/modctl.h>
     35 #include <sys/kobj.h>
     36 #include <vm/hat.h>
     37 
     38 /*
     39  * PSARC 2004/405 made hat_getkpfnum(9F) obsolete. As part of the
     40  * obsolecense, the original documented behavior will begin to be
     41  * enforced in the future; namely, hat_getkpfnum(9F) may _only_
     42  * be called with device-mapped memory virtual addresses. Since
     43  * changing hat_getkpfnum(9F) to return PFN_INVALID on kernel memory
     44  * would break a lot of modules without any warning, we've implemented
     45  * the following mechanism as a stop-gap. In a future release, this
     46  * can all be ripped out and hat_getkpfnum(9F) changed to return
     47  * PFN_INVALID if it isn't called with a device-mapped memory address.
     48  *
     49  * We keep track of each module that has used hat_getkpfnum(9F)
     50  * incorrectly. This allows us to avoid flooding the console/logs
     51  * with too many warnings about a bad module that has already been
     52  * flagged.
     53  *
     54  * On amd64 hat_getkpfnum() is never supported.
     55  */
     56 
     57 #if !defined(__amd64)
     58 
     59 #define	HAT_STACK_MAXDEPTH	15
     60 
     61 struct badcall_node {
     62 	char	*bc_modname;
     63 	int	bc_stackdepth;
     64 	pc_t	bc_callstack[HAT_STACK_MAXDEPTH];
     65 	struct badcall_node *bc_linkage;
     66 };
     67 
     68 static struct badcall_node *bad_getkpfnum_callers;
     69 
     70 /*
     71  * Common VM HAT routines.
     72  */
     73 
     74 static void
     75 printwarn(struct badcall_node *bc)
     76 {
     77 	int sf;
     78 	char *ksym;
     79 	ulong_t off;
     80 
     81 	cmn_err(CE_WARN, "Module %s is using the obsolete hat_getkpfnum(9F)",
     82 	    bc->bc_modname);
     83 	cmn_err(CE_CONT, "interface in a way that will not be supported in\n");
     84 	cmn_err(CE_CONT, "a future release of Solaris. Please contact the\n");
     85 	cmn_err(CE_CONT, "vendor that supplied the module for assistance,\n");
     86 	cmn_err(CE_CONT, "or consult the Writing Device Drivers guide,\n");
     87 	cmn_err(CE_CONT, "available from http://www.sun.com for migration\n");
     88 	cmn_err(CE_CONT, "advice.\n");
     89 	cmn_err(CE_CONT, "---\n");
     90 	cmn_err(CE_CONT, "Callstack of bad caller:\n");
     91 
     92 	for (sf = 0; sf < bc->bc_stackdepth; sf++) {
     93 		ksym = kobj_getsymname(bc->bc_callstack[sf], &off);
     94 		cmn_err(CE_CONT, "\t%s+%lx\n", ksym? ksym : "?", off);
     95 	}
     96 }
     97 
     98 
     99 void
    100 hat_getkpfnum_badcall(void *caller)
    101 {
    102 	struct badcall_node bcs;
    103 	char *modname = mod_containing_pc((caddr_t)caller);
    104 	struct badcall_node *bc;
    105 
    106 #ifdef	__sparc
    107 	/*
    108 	 * This is a hack until the ifb and jfb framebuffer drivers
    109 	 * are fixed. Right now they use hat_getkpfnum() in a way that
    110 	 * is really safe but will be incorrectly flagged as being
    111 	 * buggy.
    112 	 */
    113 	if (strcmp(modname, "ifb") == 0 || strcmp(modname, "jfb") == 0)
    114 		return;
    115 #elif defined(__i386)
    116 	/*
    117 	 * This is a hack until these ethernet drivers can be fixed
    118 	 * or EOL'd.  hat_getkpfnum() will continue to work correctly
    119 	 * until this list can be removed.
    120 	 */
    121 	if (strcmp(modname, "dnet") == 0 || strcmp(modname, "pcn") == 0 ||
    122 	    strcmp(modname, "adp") == 0)
    123 		return;
    124 #endif	/* __sparc / __i386 */
    125 
    126 	for (bc = bad_getkpfnum_callers; bc != NULL; bc = bc->bc_linkage)
    127 		if (strcmp(bc->bc_modname, modname) == 0)
    128 			return;
    129 
    130 	/*
    131 	 * We haven't seen this caller before, so create a log of
    132 	 * the callstack and module name, and emit a warning to the
    133 	 * user.
    134 	 */
    135 	bc = kmem_zalloc(sizeof (struct badcall_node), KM_NOSLEEP);
    136 	if (bc != NULL) {
    137 		bc->bc_linkage = bad_getkpfnum_callers;
    138 		bc->bc_modname = modname;
    139 		bad_getkpfnum_callers = bc;
    140 	} else {
    141 		bc = &bcs;
    142 		bc->bc_modname = modname;
    143 	}
    144 
    145 	bc->bc_stackdepth = getpcstack(bc->bc_callstack, HAT_STACK_MAXDEPTH);
    146 
    147 	printwarn(bc);
    148 }
    149 #endif /* __amd64 */
    150