From: claudio <claudio@openbsd.org>
Date: Thu, 7 Mar 2024 15:01:53 +0000 (+0000)
Subject: In _bus_dmamap_load_mbuf() ensure that for large mbuf m_len values
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=deb7b0be1b2a387092b27c5263ee89d7ae4b91bc;p=openbsd

In _bus_dmamap_load_mbuf() ensure that for large mbuf m_len values
the incr value is rounded to the page boundary. This can happen when
m_defrag() packs a TSO packet into one big mbuf cluster.

Also fix _bus_dmamap_load_uio() which has the same min(buflen, NBPG); logic.
bus_dmamap_load_uio() is unsued and will be removed after unlock.
OK miod@ bluhm@ kettenis@
---

diff --git a/sys/arch/sparc64/sparc64/machdep.c b/sys/arch/sparc64/sparc64/machdep.c
index 3e8de4190a7..135cf08c58f 100644
--- a/sys/arch/sparc64/sparc64/machdep.c
+++ b/sys/arch/sparc64/sparc64/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.208 2024/02/10 07:10:13 jsg Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.209 2024/03/07 15:01:53 claudio Exp $	*/
 /*	$NetBSD: machdep.c,v 1.108 2001/07/24 19:30:14 eeh Exp $ */
 
 /*-
@@ -1014,7 +1014,8 @@ _bus_dmamap_load_mbuf(bus_dma_tag_t t, bus_dma_tag_t t0, bus_dmamap_t map,
 			paddr_t pa;
 			long incr;
 
-			incr = min(buflen, NBPG);
+			incr = min(buflen,
+			    PAGE_SIZE - ((u_long)vaddr & PGOFSET));
 
 			if (pmap_extract(pmap_kernel(), vaddr, &pa) == FALSE) {
 #ifdef DIAGNOSTIC
@@ -1100,7 +1101,9 @@ _bus_dmamap_load_uio(bus_dma_tag_t t, bus_dma_tag_t t0, bus_dmamap_t map,
 			paddr_t pa;
 			long incr;
 
-			incr = min(buflen, NBPG);
+			incr = min(buflen,
+			    PAGE_SIZE - ((u_long)vaddr & PGOFSET));
+
 			(void) pmap_extract(pmap_kernel(), vaddr, &pa);
 			buflen -= incr;
 			vaddr += incr;