Fix partition alignment and image rounding when any of -P (block size),

-T (track size) or -H (number of heads) is given:
o   scheme_metadata() always rounded to the block size.  This is not
    always valid (e.g. vtoc8 that must have partitions start at cylinder
    boundaries).
o   The bsd and vtoc8 schemes "resized" the image to make it match the
    geometry, but since the geometry is an approximation and the size
    of the image computed from cylinders * heads * sectors is always
    smaller than the original image size, the partition information ran
    out of bounds.

The fix is to have scheme_metadata() simply pass it's arguments to the
per-scheme metadata callback, so that schemes not only know where the
metadata is to go, but also what the current block address is. It's now
up to the per-scheme callback to reserve room for metadata and to make
sure alignment and rounding is applied.

The BSD scheme now has the most elaborate alignment and rounding. Just
to make the point: partitions are aligned on block boundaries, but the
image is rounded to the next cyclinder boundary.

vtoc8 now properly has all partitions aligned (and rounded) to the
cyclinder boundary.

Obtained from:	Juniper Networks, Inc.
MFC after:	3 days
This commit is contained in:
Marcel Moolenaar 2014-09-19 23:16:02 +00:00
parent a4b2ac79e4
commit 53fcdb2d1a
10 changed files with 54 additions and 54 deletions

View File

@ -57,13 +57,12 @@ static struct mkimg_alias apm_aliases[] = {
{ ALIAS_NONE, 0 }
};
static u_int
apm_metadata(u_int where)
static lba_t
apm_metadata(u_int where, lba_t blk)
{
u_int secs;
secs = (where == SCHEME_META_IMG_START) ? nparts + 2 : 0;
return (secs);
blk += (where == SCHEME_META_IMG_START) ? nparts + 2 : 0;
return (round_block(blk));
}
static int

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@ -52,13 +52,17 @@ static struct mkimg_alias bsd_aliases[] = {
{ ALIAS_NONE, 0 }
};
static u_int
bsd_metadata(u_int where)
static lba_t
bsd_metadata(u_int where, lba_t blk)
{
u_int secs;
secs = BBSIZE / secsz;
return ((where == SCHEME_META_IMG_START) ? secs : 0);
if (where == SCHEME_META_IMG_START)
blk += BBSIZE / secsz;
else if (where == SCHEME_META_IMG_END)
blk = round_cylinder(blk);
else
blk = round_block(blk);
return (blk);
}
static int
@ -83,12 +87,6 @@ bsd_write(lba_t imgsz, void *bootcode)
bsdparts = nparts + 1; /* Account for c partition */
if (bsdparts < MAXPARTITIONS)
bsdparts = MAXPARTITIONS;
imgsz = (lba_t)ncyls * nheads * nsecs;
error = image_set_size(imgsz);
if (error) {
free(buf);
return (error);
}
d = (void *)(buf + secsz);
le32enc(&d->d_magic, DISKMAGIC);

View File

@ -49,13 +49,12 @@ static struct mkimg_alias ebr_aliases[] = {
{ ALIAS_NONE, 0 }
};
static u_int
ebr_metadata(u_int where)
static lba_t
ebr_metadata(u_int where, lba_t blk)
{
u_int secs;
secs = (where == SCHEME_META_PART_BEFORE) ? nsecs : 0;
return (secs);
blk += (where == SCHEME_META_PART_BEFORE) ? 1 : 0;
return (round_track(blk));
}
static void

View File

@ -153,17 +153,15 @@ gpt_tblsz(void)
return ((nparts + ents - 1) / ents);
}
static u_int
gpt_metadata(u_int where)
static lba_t
gpt_metadata(u_int where, lba_t blk)
{
u_int secs;
if (where != SCHEME_META_IMG_START && where != SCHEME_META_IMG_END)
return (0);
secs = gpt_tblsz();
secs += (where == SCHEME_META_IMG_START) ? 2 : 1;
return (secs);
if (where == SCHEME_META_IMG_START || where == SCHEME_META_IMG_END) {
blk += gpt_tblsz();
blk += (where == SCHEME_META_IMG_START) ? 2 : 1;
}
return (round_block(blk));
}
static int

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@ -50,13 +50,12 @@ static struct mkimg_alias mbr_aliases[] = {
{ ALIAS_NONE, 0 } /* Keep last! */
};
static u_int
mbr_metadata(u_int where)
static lba_t
mbr_metadata(u_int where, lba_t blk)
{
u_int secs;
secs = (where == SCHEME_META_IMG_START) ? nsecs : 0;
return (secs);
blk += (where == SCHEME_META_IMG_START) ? 1 : 0;
return (round_track(blk));
}
static void

View File

@ -66,6 +66,21 @@ round_block(lba_t n)
return ((n + b - 1) & ~(b - 1));
}
static inline lba_t
round_cylinder(lba_t n)
{
u_int cyl = nsecs * nheads;
u_int r = n % cyl;
return ((r == 0) ? n : n + cyl - r);
}
static inline lba_t
round_track(lba_t n)
{
u_int r = n % nsecs;
return ((r == 0) ? n : n + nsecs - r);
}
#if !defined(SPARSE_WRITE)
#define sparse_write write
#else

View File

@ -59,13 +59,12 @@ static struct mkimg_alias pc98_aliases[] = {
{ ALIAS_NONE, 0 }
};
static u_int
pc98_metadata(u_int where)
static lba_t
pc98_metadata(u_int where, lba_t blk)
{
u_int secs;
secs = PC98_BOOTCODESZ / secsz;
return ((where == SCHEME_META_IMG_START) ? secs : 0);
if (where == SCHEME_META_IMG_START)
blk += PC98_BOOTCODESZ / secsz;
return (round_track(blk));
}
static void

View File

@ -171,10 +171,8 @@ scheme_max_secsz(void)
lba_t
scheme_metadata(u_int where, lba_t start)
{
lba_t secs;
secs = scheme->metadata(where);
return (round_block(start + secs));
return (scheme->metadata(where, start));
}
int

View File

@ -62,7 +62,7 @@ struct mkimg_scheme {
const char *name;
const char *description;
struct mkimg_alias *aliases;
u_int (*metadata)(u_int);
lba_t (*metadata)(u_int, lba_t);
#define SCHEME_META_IMG_START 1
#define SCHEME_META_IMG_END 2
#define SCHEME_META_PART_BEFORE 3

View File

@ -53,13 +53,12 @@ static struct mkimg_alias vtoc8_aliases[] = {
{ ALIAS_NONE, 0 }
};
static u_int
vtoc8_metadata(u_int where)
static lba_t
vtoc8_metadata(u_int where, lba_t blk)
{
u_int secs;
secs = (where == SCHEME_META_IMG_START) ? nsecs * nheads : 0;
return (secs);
blk += (where == SCHEME_META_IMG_START) ? 1 : 0;
return (round_cylinder(blk));
}
static int
@ -87,10 +86,6 @@ vtoc8_write(lba_t imgsz, void *bootcode __unused)
be16enc(&vtoc8.nsecs, nsecs);
be16enc(&vtoc8.magic, VTOC_MAGIC);
error = image_set_size(imgsz);
if (error)
return (error);
be32enc(&vtoc8.map[VTOC_RAW_PART].nblks, imgsz);
STAILQ_FOREACH(part, &partlist, link) {
n = part->index + ((part->index >= VTOC_RAW_PART) ? 1 : 0);