Module Name: src
Committed By: tsutsui
Date: Sat Apr 7 03:08:33 UTC 2012
Modified Files:
src/distrib/utils/sysinst: mbr.c
Log Message:
Use 1MB alignment rather than the default 63 sectors for
fdisk partition boundary for >128GB disks, as fdisk(8) does.
No particular comments for my PR install/45990.
To generate a diff of this commit:
cvs rdiff -u -r1.89 -r1.90 src/distrib/utils/sysinst/mbr.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/distrib/utils/sysinst/mbr.c
diff -u src/distrib/utils/sysinst/mbr.c:1.89 src/distrib/utils/sysinst/mbr.c:1.90
--- src/distrib/utils/sysinst/mbr.c:1.89 Thu Jan 5 21:29:24 2012
+++ src/distrib/utils/sysinst/mbr.c Sat Apr 7 03:08:33 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: mbr.c,v 1.89 2012/01/05 21:29:24 christos Exp $ */
+/* $NetBSD: mbr.c,v 1.90 2012/04/07 03:08:33 tsutsui Exp $ */
/*
* Copyright 1997 Piermont Information Systems Inc.
@@ -113,6 +113,10 @@ static int get_mapping(struct mbr_partit
daddr_t *);
static void convert_mbr_chs(int, int, int, uint8_t *, uint8_t *,
uint8_t *, uint32_t);
+static void get_ptn_alignment(struct mbr_partition *);
+
+static unsigned int ptn_alignment;
+static unsigned int ptn_0_offset;
/*
* Notes on the extended partition editor.
@@ -462,8 +466,9 @@ set_mbr_type(menudesc *m, void *arg)
return 0;
mbri->extended = ext;
ext->sector = mbrp->mbrp_start;
- ext->mbr.mbr_parts[0].mbrp_start = bsec;
- ext->mbr.mbr_parts[0].mbrp_size = mbrp->mbrp_size - bsec;
+ ext->mbr.mbr_parts[0].mbrp_start = ptn_0_offset;
+ ext->mbr.mbr_parts[0].mbrp_size =
+ mbrp->mbrp_size - ptn_0_offset;
}
mbrp->mbrp_type = type;
@@ -742,14 +747,14 @@ edit_mbr_size(menudesc *m, void *arg)
/* If unchanged, don't re-round size */
new = dflt;
else {
- /* Round end to cylinder boundary */
+ /* Round end to the partition alignment */
if (sizemult != 1) {
new *= sizemult;
- new += rounddown(start, current_cylsize);
- new = roundup(new, current_cylsize);
+ new += rounddown(start, ptn_alignment);
+ new = roundup(new, ptn_alignment);
new -= start;
while (new <= 0)
- new += current_cylsize;
+ new += ptn_alignment;
}
}
if (new > max)
@@ -1237,12 +1242,12 @@ mbr_use_wholedisk(mbr_info_t *mbri)
memset(&mbri->mbrb, 0, sizeof mbri->mbrb);
#endif
part[0].mbrp_type = MBR_PTYPE_NETBSD;
- part[0].mbrp_size = dlsize - bsec;
- part[0].mbrp_start = bsec;
+ part[0].mbrp_size = dlsize - ptn_0_offset;
+ part[0].mbrp_start = ptn_0_offset;
part[0].mbrp_flag = MBR_PFLAG_ACTIVE;
- ptstart = bsec;
- ptsize = dlsize - bsec;
+ ptstart = ptn_0_offset;
+ ptsize = dlsize - ptn_0_offset;
return 1;
}
@@ -1450,6 +1455,10 @@ read_mbr(const char *disk, mbr_info_t *m
*/
if (bsec == 0)
bsec = dlsec;
+ ptn_0_offset = bsec;
+ /* use 1MB default offset on large disks as fdisk(8) */
+ if (dlsize > 2048 * 1024 * 128)
+ ptn_0_offset = 2048;
memset(mbri, 0, sizeof *mbri);
@@ -1467,7 +1476,9 @@ read_mbr(const char *disk, mbr_info_t *m
break;
mbrp = &mbrs->mbr_parts[0];
- if (ext_base != 0) {
+ if (ext_base == 0) {
+ get_ptn_alignment(mbrp);
+ } else {
/* sanity check extended chain */
if (MBR_IS_EXTENDED(mbrp[0].mbrp_type))
break;
@@ -1547,9 +1558,9 @@ read_mbr(const char *disk, mbr_info_t *m
ext->sector = base;
ext->mbr.mbr_magic = htole16(MBR_MAGIC);
ext->mbr.mbr_parts[1] = mbrp[1];
- ext->mbr.mbr_parts[0].mbrp_start = bsec;
+ ext->mbr.mbr_parts[0].mbrp_start = ptn_0_offset;
ext->mbr.mbr_parts[0].mbrp_size =
- ext_base + limit - base - bsec;
+ ext_base + limit - base - ptn_0_offset;
mbrp[1].mbrp_type = MBR_PTYPE_EXT;
mbrp[1].mbrp_start = base - ext_base;
mbrp[1].mbrp_size = limit - mbrp[1].mbrp_start;
@@ -1850,3 +1861,36 @@ get_mapping(struct mbr_partition *parts,
return 0;
}
+
+/*
+ * Determine partition boundary alignment as fdisk(8) does.
+ */
+static void
+get_ptn_alignment(struct mbr_partition *mbrp0)
+{
+ uint32_t ptn_0_base, ptn_0_limit;
+
+ /* Default to using 'traditional' cylinder alignment */
+ ptn_alignment = bhead * bsec;
+ ptn_0_offset = bsec;
+
+ if (mbrp0->mbrp_type != 0) {
+ /* Try to copy offset of first partition */
+ ptn_0_base = le32toh(mbrp0->mbrp_start);
+ ptn_0_limit = ptn_0_base + le32toh(mbrp0->mbrp_size);
+ if (!(ptn_0_limit & 2047)) {
+ /* Partition ends on a 1MB boundary, align to 1MB */
+ ptn_alignment = 2048;
+ if (ptn_0_base <= 2048
+ && !(ptn_0_base & (ptn_0_base - 1))) {
+ /* ptn_base is a power of 2, use it */
+ ptn_0_offset = ptn_0_base;
+ }
+ }
+ } else {
+ /* Use 1MB offset for large (>128GB) disks */
+ if (dlsize > 2048 * 1024 * 128)
+ ptn_alignment = 2048;
+ ptn_0_offset = 2048;
+ }
+}
