xref: /illumos-gate/usr/src/cmd/mdb/common/mdb/mdb_umem.c (revision 258e8624)
17c478bd9Sstevel@tonic-gate /*
27c478bd9Sstevel@tonic-gate  * CDDL HEADER START
37c478bd9Sstevel@tonic-gate  *
47c478bd9Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
57c478bd9Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
67c478bd9Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
77c478bd9Sstevel@tonic-gate  * with the License.
87c478bd9Sstevel@tonic-gate  *
97c478bd9Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
107c478bd9Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
117c478bd9Sstevel@tonic-gate  * See the License for the specific language governing permissions
127c478bd9Sstevel@tonic-gate  * and limitations under the License.
137c478bd9Sstevel@tonic-gate  *
147c478bd9Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
157c478bd9Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
167c478bd9Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
177c478bd9Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
187c478bd9Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
197c478bd9Sstevel@tonic-gate  *
207c478bd9Sstevel@tonic-gate  * CDDL HEADER END
217c478bd9Sstevel@tonic-gate  */
227c478bd9Sstevel@tonic-gate /*
237c478bd9Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
247c478bd9Sstevel@tonic-gate  * Use is subject to license terms.
257c478bd9Sstevel@tonic-gate  */
267c478bd9Sstevel@tonic-gate 
277c478bd9Sstevel@tonic-gate /*
287c478bd9Sstevel@tonic-gate  * These routines simply provide wrappers around malloc(3C) and free(3C)
297c478bd9Sstevel@tonic-gate  * for now.  In the future we hope to provide a userland equivalent to
307c478bd9Sstevel@tonic-gate  * the kmem allocator, including cache allocators.
317c478bd9Sstevel@tonic-gate  */
327c478bd9Sstevel@tonic-gate 
337c478bd9Sstevel@tonic-gate #include <strings.h>
347c478bd9Sstevel@tonic-gate #include <stdlib.h>
357c478bd9Sstevel@tonic-gate #include <poll.h>
367c478bd9Sstevel@tonic-gate 
377c478bd9Sstevel@tonic-gate #ifdef _KMDB
387c478bd9Sstevel@tonic-gate #include <kmdb/kmdb_fault.h>
397c478bd9Sstevel@tonic-gate #endif
407c478bd9Sstevel@tonic-gate #include <mdb/mdb_debug.h>
417c478bd9Sstevel@tonic-gate #include <mdb/mdb_stdlib.h>
427c478bd9Sstevel@tonic-gate #include <mdb/mdb_frame.h>
437c478bd9Sstevel@tonic-gate #include <mdb/mdb_umem.h>
447c478bd9Sstevel@tonic-gate #include <mdb/mdb_err.h>
457c478bd9Sstevel@tonic-gate #include <mdb/mdb.h>
467c478bd9Sstevel@tonic-gate 
477c478bd9Sstevel@tonic-gate #define	UMF_DEBUG			0x1
487c478bd9Sstevel@tonic-gate 
497c478bd9Sstevel@tonic-gate #ifdef DEBUG
507c478bd9Sstevel@tonic-gate int mdb_umem_flags = UMF_DEBUG;
517c478bd9Sstevel@tonic-gate #else
527c478bd9Sstevel@tonic-gate int mdb_umem_flags = 0;
537c478bd9Sstevel@tonic-gate #endif
547c478bd9Sstevel@tonic-gate 
557c478bd9Sstevel@tonic-gate struct mdb_mblk {
567c478bd9Sstevel@tonic-gate 	void *blk_addr;			/* address of allocated block */
577c478bd9Sstevel@tonic-gate 	size_t blk_size;		/* size of block in bytes */
587c478bd9Sstevel@tonic-gate 	struct mdb_mblk *blk_next;	/* link to next block */
597c478bd9Sstevel@tonic-gate };
607c478bd9Sstevel@tonic-gate 
617c478bd9Sstevel@tonic-gate /*ARGSUSED*/
627c478bd9Sstevel@tonic-gate static void *
mdb_umem_handler(size_t nbytes,size_t align,uint_t flags)637c478bd9Sstevel@tonic-gate mdb_umem_handler(size_t nbytes, size_t align, uint_t flags)
647c478bd9Sstevel@tonic-gate {
657c478bd9Sstevel@tonic-gate #ifdef _KMDB
667c478bd9Sstevel@tonic-gate 
677c478bd9Sstevel@tonic-gate 	/*
687c478bd9Sstevel@tonic-gate 	 * kmdb has a fixed, dedicated VA range in which to play.  This range
697c478bd9Sstevel@tonic-gate 	 * won't change size while the debugger is running, regardless of how
707c478bd9Sstevel@tonic-gate 	 * long we wait.  As a result, the only sensible course of action is
717c478bd9Sstevel@tonic-gate 	 * to fail the request.  If we're here, however, the request was made
727c478bd9Sstevel@tonic-gate 	 * with UM_SLEEP.  The caller is thus not expecting a NULL back.  We'll
737c478bd9Sstevel@tonic-gate 	 * have to fail the current dcmd set.
747c478bd9Sstevel@tonic-gate 	 */
757c478bd9Sstevel@tonic-gate 	if (mdb.m_depth > 0) {
767c478bd9Sstevel@tonic-gate 		warn("failed to allocate %lu bytes -- recovering\n",
777c478bd9Sstevel@tonic-gate 		    (ulong_t)nbytes);
787c478bd9Sstevel@tonic-gate 
797c478bd9Sstevel@tonic-gate 		kmdb_print_stack();
807c478bd9Sstevel@tonic-gate 
817c478bd9Sstevel@tonic-gate 		longjmp(mdb.m_frame->f_pcb, MDB_ERR_NOMEM);
827c478bd9Sstevel@tonic-gate 	}
837c478bd9Sstevel@tonic-gate 
847c478bd9Sstevel@tonic-gate #else
857c478bd9Sstevel@tonic-gate 
867c478bd9Sstevel@tonic-gate 	/*
877c478bd9Sstevel@tonic-gate 	 * mdb, on the other hand, can afford to wait, as someone may actually
887c478bd9Sstevel@tonic-gate 	 * free something.
897c478bd9Sstevel@tonic-gate 	 */
907c478bd9Sstevel@tonic-gate 	if (errno == EAGAIN) {
917c478bd9Sstevel@tonic-gate 		void *ptr = NULL;
927c478bd9Sstevel@tonic-gate 		char buf[64];
937c478bd9Sstevel@tonic-gate 
947c478bd9Sstevel@tonic-gate 		(void) mdb_iob_snprintf(buf, sizeof (buf),
957c478bd9Sstevel@tonic-gate 		    "[ sleeping for %lu bytes of free memory ... ]",
967c478bd9Sstevel@tonic-gate 		    (ulong_t)nbytes);
977c478bd9Sstevel@tonic-gate 
987c478bd9Sstevel@tonic-gate 		(void) mdb_iob_puts(mdb.m_err, buf);
997c478bd9Sstevel@tonic-gate 		(void) mdb_iob_flush(mdb.m_err);
1007c478bd9Sstevel@tonic-gate 
1017c478bd9Sstevel@tonic-gate 		do {
1027c478bd9Sstevel@tonic-gate 			(void) poll(NULL, 0, 1000);
1037c478bd9Sstevel@tonic-gate 			if (align != 0)
1047c478bd9Sstevel@tonic-gate 				ptr = memalign(align, nbytes);
1057c478bd9Sstevel@tonic-gate 			else
1067c478bd9Sstevel@tonic-gate 				ptr = malloc(nbytes);
1077c478bd9Sstevel@tonic-gate 		} while (ptr == NULL && errno == EAGAIN);
1087c478bd9Sstevel@tonic-gate 
1097c478bd9Sstevel@tonic-gate 		if (ptr != NULL)
1107c478bd9Sstevel@tonic-gate 			return (ptr);
1117c478bd9Sstevel@tonic-gate 
1127c478bd9Sstevel@tonic-gate 		(void) memset(buf, '\b', strlen(buf));
1137c478bd9Sstevel@tonic-gate 		(void) mdb_iob_puts(mdb.m_err, buf);
1147c478bd9Sstevel@tonic-gate 		(void) mdb_iob_flush(mdb.m_err);
1157c478bd9Sstevel@tonic-gate 
1167c478bd9Sstevel@tonic-gate 		(void) memset(buf, ' ', strlen(buf));
1177c478bd9Sstevel@tonic-gate 		(void) mdb_iob_puts(mdb.m_err, buf);
1187c478bd9Sstevel@tonic-gate 		(void) mdb_iob_flush(mdb.m_err);
1197c478bd9Sstevel@tonic-gate 
1207c478bd9Sstevel@tonic-gate 		(void) memset(buf, '\b', strlen(buf));
1217c478bd9Sstevel@tonic-gate 		(void) mdb_iob_puts(mdb.m_err, buf);
1227c478bd9Sstevel@tonic-gate 		(void) mdb_iob_flush(mdb.m_err);
1237c478bd9Sstevel@tonic-gate 	}
1247c478bd9Sstevel@tonic-gate #endif
1257c478bd9Sstevel@tonic-gate 
1267c478bd9Sstevel@tonic-gate 	die("failed to allocate %lu bytes -- terminating\n", (ulong_t)nbytes);
1277c478bd9Sstevel@tonic-gate 
1287c478bd9Sstevel@tonic-gate 	/*NOTREACHED*/
1297c478bd9Sstevel@tonic-gate 
1307c478bd9Sstevel@tonic-gate 	return (NULL);
1317c478bd9Sstevel@tonic-gate }
1327c478bd9Sstevel@tonic-gate 
1337c478bd9Sstevel@tonic-gate static void
mdb_umem_gc_enter(void * ptr,size_t nbytes)1347c478bd9Sstevel@tonic-gate mdb_umem_gc_enter(void *ptr, size_t nbytes)
1357c478bd9Sstevel@tonic-gate {
1367c478bd9Sstevel@tonic-gate 	mdb_mblk_t *blkp = mdb_alloc(sizeof (mdb_mblk_t), UM_SLEEP);
1377c478bd9Sstevel@tonic-gate 
1387c478bd9Sstevel@tonic-gate 	blkp->blk_addr = ptr;
1397c478bd9Sstevel@tonic-gate 	blkp->blk_size = nbytes;
1407c478bd9Sstevel@tonic-gate 	blkp->blk_next = mdb.m_frame->f_mblks;
1417c478bd9Sstevel@tonic-gate 
1427c478bd9Sstevel@tonic-gate 	mdb.m_frame->f_mblks = blkp;
1437c478bd9Sstevel@tonic-gate }
1447c478bd9Sstevel@tonic-gate 
1457c478bd9Sstevel@tonic-gate /*
1467c478bd9Sstevel@tonic-gate  * If we're compiled in debug mode, we use this function (gratuitously
1477c478bd9Sstevel@tonic-gate  * stolen from kmem.c) to set uninitialized and freed regions to
1487c478bd9Sstevel@tonic-gate  * special bit patterns.
1497c478bd9Sstevel@tonic-gate  */
1507c478bd9Sstevel@tonic-gate static void
mdb_umem_copy_pattern(uint32_t pattern,void * buf_arg,size_t size)1517c478bd9Sstevel@tonic-gate mdb_umem_copy_pattern(uint32_t pattern, void *buf_arg, size_t size)
1527c478bd9Sstevel@tonic-gate {
1537c478bd9Sstevel@tonic-gate 	/* LINTED - alignment of bufend */
1547c478bd9Sstevel@tonic-gate 	uint32_t *bufend = (uint32_t *)((char *)buf_arg + size);
1557c478bd9Sstevel@tonic-gate 	uint32_t *buf = buf_arg;
1567c478bd9Sstevel@tonic-gate 
1577c478bd9Sstevel@tonic-gate 	while (buf < bufend - 3) {
1587c478bd9Sstevel@tonic-gate 		buf[3] = buf[2] = buf[1] = buf[0] = pattern;
1597c478bd9Sstevel@tonic-gate 		buf += 4;
1607c478bd9Sstevel@tonic-gate 	}
1617c478bd9Sstevel@tonic-gate 
1627c478bd9Sstevel@tonic-gate 	while (buf < bufend)
1637c478bd9Sstevel@tonic-gate 		*buf++ = pattern;
1647c478bd9Sstevel@tonic-gate }
1657c478bd9Sstevel@tonic-gate 
1667c478bd9Sstevel@tonic-gate void *
mdb_alloc_align(size_t nbytes,size_t align,uint_t flags)1677c478bd9Sstevel@tonic-gate mdb_alloc_align(size_t nbytes, size_t align, uint_t flags)
1687c478bd9Sstevel@tonic-gate {
1697c478bd9Sstevel@tonic-gate 	void *ptr;
170*258e8624SRobert Mustacchi 	size_t obytes = nbytes;
1717c478bd9Sstevel@tonic-gate 
172*258e8624SRobert Mustacchi 	if (nbytes == 0 || nbytes > MDB_ALLOC_MAX)
1737c478bd9Sstevel@tonic-gate 		return (NULL);
1747c478bd9Sstevel@tonic-gate 
1757c478bd9Sstevel@tonic-gate 	nbytes = (nbytes + sizeof (uint32_t) - 1) & ~(sizeof (uint32_t) - 1);
176*258e8624SRobert Mustacchi 	if (nbytes < obytes || nbytes == 0)
177*258e8624SRobert Mustacchi 		return (NULL);
1787c478bd9Sstevel@tonic-gate 
1797c478bd9Sstevel@tonic-gate 	if (align != 0)
1807c478bd9Sstevel@tonic-gate 		ptr = memalign(align, nbytes);
1817c478bd9Sstevel@tonic-gate 	else
1827c478bd9Sstevel@tonic-gate 		ptr = malloc(nbytes);
1837c478bd9Sstevel@tonic-gate 
1847c478bd9Sstevel@tonic-gate 	if (flags & UM_SLEEP) {
1857c478bd9Sstevel@tonic-gate 		while (ptr == NULL)
1867c478bd9Sstevel@tonic-gate 			ptr = mdb_umem_handler(nbytes, align, flags);
1877c478bd9Sstevel@tonic-gate 	}
1887c478bd9Sstevel@tonic-gate 
1897c478bd9Sstevel@tonic-gate 	if (ptr != NULL && (mdb_umem_flags & UMF_DEBUG) != 0)
1907c478bd9Sstevel@tonic-gate 		mdb_umem_copy_pattern(UMEM_UNINITIALIZED_PATTERN, ptr, nbytes);
1917c478bd9Sstevel@tonic-gate 
1927c478bd9Sstevel@tonic-gate 	if (flags & UM_GC)
1937c478bd9Sstevel@tonic-gate 		mdb_umem_gc_enter(ptr, nbytes);
1947c478bd9Sstevel@tonic-gate 
1957c478bd9Sstevel@tonic-gate 	return (ptr);
1967c478bd9Sstevel@tonic-gate }
1977c478bd9Sstevel@tonic-gate 
1987c478bd9Sstevel@tonic-gate void *
mdb_alloc(size_t nbytes,uint_t flags)1997c478bd9Sstevel@tonic-gate mdb_alloc(size_t nbytes, uint_t flags)
2007c478bd9Sstevel@tonic-gate {
2017c478bd9Sstevel@tonic-gate 	return (mdb_alloc_align(nbytes, 0, flags));
2027c478bd9Sstevel@tonic-gate }
2037c478bd9Sstevel@tonic-gate 
2047c478bd9Sstevel@tonic-gate void *
mdb_zalloc(size_t nbytes,uint_t flags)2057c478bd9Sstevel@tonic-gate mdb_zalloc(size_t nbytes, uint_t flags)
2067c478bd9Sstevel@tonic-gate {
2077c478bd9Sstevel@tonic-gate 	void *ptr = mdb_alloc(nbytes, flags);
2087c478bd9Sstevel@tonic-gate 
2097c478bd9Sstevel@tonic-gate 	if (ptr != NULL)
2107c478bd9Sstevel@tonic-gate 		bzero(ptr, nbytes);
2117c478bd9Sstevel@tonic-gate 
2127c478bd9Sstevel@tonic-gate 	return (ptr);
2137c478bd9Sstevel@tonic-gate }
2147c478bd9Sstevel@tonic-gate 
2157c478bd9Sstevel@tonic-gate void
mdb_free(void * ptr,size_t nbytes)2167c478bd9Sstevel@tonic-gate mdb_free(void *ptr, size_t nbytes)
2177c478bd9Sstevel@tonic-gate {
2187c478bd9Sstevel@tonic-gate 	ASSERT(ptr != NULL || nbytes == 0);
2197c478bd9Sstevel@tonic-gate 
2207c478bd9Sstevel@tonic-gate 	nbytes = (nbytes + sizeof (uint32_t) - 1) & ~(sizeof (uint32_t) - 1);
2217c478bd9Sstevel@tonic-gate 
2227c478bd9Sstevel@tonic-gate 	if (ptr != NULL) {
2237c478bd9Sstevel@tonic-gate 		if (mdb_umem_flags & UMF_DEBUG)
2247c478bd9Sstevel@tonic-gate 			mdb_umem_copy_pattern(UMEM_FREE_PATTERN, ptr, nbytes);
2257c478bd9Sstevel@tonic-gate 		free(ptr);
2267c478bd9Sstevel@tonic-gate 	}
2277c478bd9Sstevel@tonic-gate }
2287c478bd9Sstevel@tonic-gate 
2297c478bd9Sstevel@tonic-gate void
mdb_free_align(void * ptr,size_t nbytes)2307c478bd9Sstevel@tonic-gate mdb_free_align(void *ptr, size_t nbytes)
2317c478bd9Sstevel@tonic-gate {
2327c478bd9Sstevel@tonic-gate 	mdb_free(ptr, nbytes);
2337c478bd9Sstevel@tonic-gate }
2347c478bd9Sstevel@tonic-gate 
2357c478bd9Sstevel@tonic-gate void
mdb_recycle(mdb_mblk_t ** blkpp)2367c478bd9Sstevel@tonic-gate mdb_recycle(mdb_mblk_t **blkpp)
2377c478bd9Sstevel@tonic-gate {
2387c478bd9Sstevel@tonic-gate 	mdb_mblk_t *blkp, *nblkp;
2397c478bd9Sstevel@tonic-gate 
2407c478bd9Sstevel@tonic-gate 	for (blkp = *blkpp; blkp != NULL; blkp = nblkp) {
2417c478bd9Sstevel@tonic-gate 		mdb_dprintf(MDB_DBG_UMEM,
2427c478bd9Sstevel@tonic-gate 		    "garbage collect %p size %lu bytes\n", blkp->blk_addr,
2437c478bd9Sstevel@tonic-gate 		    (ulong_t)blkp->blk_size);
2447c478bd9Sstevel@tonic-gate 
2457c478bd9Sstevel@tonic-gate 		nblkp = blkp->blk_next;
2467c478bd9Sstevel@tonic-gate 		mdb_free(blkp->blk_addr, blkp->blk_size);
2477c478bd9Sstevel@tonic-gate 		mdb_free(blkp, sizeof (mdb_mblk_t));
2487c478bd9Sstevel@tonic-gate 	}
2497c478bd9Sstevel@tonic-gate 
2507c478bd9Sstevel@tonic-gate 	*blkpp = NULL;
2517c478bd9Sstevel@tonic-gate }
252