Module Name: src
Committed By: skrll
Date: Tue Sep 8 10:30:17 UTC 2020
Modified Files:
src/sys/arch/arm/arm32: bus_dma.c
Log Message:
A few bus_dmatag_subregion fixes
- return EOPNOTSUPP if min_addr isn't less than max_addr
- fix the subset check to ensure that all the ranges in the parent tag are
within the {min,max}_addr range. If so we can just continue to use the
parent tag.
- when building the new ranges read the parent tag range rather than un-
initialised memory.
- remove the max_addr != 0xffffffff check - the overflow should be handled
by the unsigned arithmetic for arm32.
- add a KASSERT
- add comments
To generate a diff of this commit:
cvs rdiff -u -r1.122 -r1.123 src/sys/arch/arm/arm32/bus_dma.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/arm/arm32/bus_dma.c
diff -u src/sys/arch/arm/arm32/bus_dma.c:1.122 src/sys/arch/arm/arm32/bus_dma.c:1.123
--- src/sys/arch/arm/arm32/bus_dma.c:1.122 Sat Jun 20 07:10:36 2020
+++ src/sys/arch/arm/arm32/bus_dma.c Tue Sep 8 10:30:17 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: bus_dma.c,v 1.122 2020/06/20 07:10:36 skrll Exp $ */
+/* $NetBSD: bus_dma.c,v 1.123 2020/09/08 10:30:17 skrll Exp $ */
/*-
* Copyright (c) 1996, 1997, 1998, 2020 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
#include "opt_cputypes.h"
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.122 2020/06/20 07:10:36 skrll Exp $");
+__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.123 2020/09/08 10:30:17 skrll Exp $");
#include <sys/param.h>
@@ -1811,6 +1811,8 @@ int
_bus_dmatag_subregion(bus_dma_tag_t tag, bus_addr_t min_addr,
bus_addr_t max_addr, bus_dma_tag_t *newtag, int flags)
{
+ if (min_addr >= max_addr)
+ return EOPNOTSUPP;
#ifdef _ARM32_NEED_BUS_DMA_BOUNCE
struct arm32_dma_range *dr;
@@ -1818,9 +1820,15 @@ _bus_dmatag_subregion(bus_dma_tag_t tag,
size_t nranges = 0;
size_t i;
for (i = 0, dr = tag->_ranges; i < tag->_nranges; i++, dr++) {
- if (dr->dr_sysbase <= min_addr
- && max_addr <= dr->dr_sysbase + dr->dr_len - 1) {
+ /*
+ * Are all the ranges in the parent tag a subset of the new
+ * range? If yes, we can continue to use the parent tag.
+ */
+ if (dr->dr_sysbase >= min_addr
+ && dr->dr_sysbase + dr->dr_len - 1 <= max_addr) {
subset = true;
+ } else {
+ subset = false;
}
if (min_addr <= dr->dr_sysbase + dr->dr_len
&& max_addr >= dr->dr_sysbase) {
@@ -1854,22 +1862,35 @@ _bus_dmatag_subregion(bus_dma_tag_t tag,
dr->dr_busbase = min_addr;
dr->dr_len = max_addr + 1 - min_addr;
} else {
- for (i = 0; i < nranges; i++) {
- if (min_addr > dr->dr_sysbase + dr->dr_len
- || max_addr < dr->dr_sysbase)
+ struct arm32_dma_range *pdr;
+
+ for (i = 0, pdr = tag->_ranges; i < tag->_nranges; i++, pdr++) {
+ KASSERT(nranges != 0);
+
+ if (min_addr > pdr->dr_sysbase + pdr->dr_len
+ || max_addr < pdr->dr_sysbase) {
+ /*
+ * this range doesn't overlap with new limits,
+ * so skip.
+ */
continue;
- dr[0] = tag->_ranges[i];
+ }
+ /*
+ * Copy the range and adjust to fit within the new
+ * limits
+ */
+ dr[0] = pdr[0];
if (dr->dr_sysbase < min_addr) {
psize_t diff = min_addr - dr->dr_sysbase;
dr->dr_busbase += diff;
dr->dr_len -= diff;
dr->dr_sysbase += diff;
}
- if (max_addr != 0xffffffff
- && max_addr + 1 < dr->dr_sysbase + dr->dr_len) {
+ if (max_addr <= dr->dr_sysbase + dr->dr_len - 1) {
dr->dr_len = max_addr + 1 - dr->dr_sysbase;
}
dr++;
+ nranges--;
}
}
