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Added a description of SUN Disk Label for SUN SPARC machines.

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This commit is contained in:
Thomas Schmitt 2010-11-01 16:05:47 +01:00
parent 8ad92a08ea
commit ea8da1f7d3
1 changed files with 106 additions and 1 deletions
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107
doc/boot_sectors.txt
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@ -11,7 +11,7 @@ This information is collected from various sources. Some is backed by
specifications, some is just rumor which happens to work (maybe not even that).
Content
Content
EL Torito CD booting, for PC-BIOS x86, PowerPC, (old) Mac, EFI.
@ -23,6 +23,8 @@ MIPS Volume Header, for MIPS Big Endian, e.g. SGI Indigo2.
DEC Boot Block, for MIPS Little Endian , e.g. DECstation.
SUN Disk Label and boot images, for SUN SPARC
------------------------------------------------------------------------------
@ -648,6 +650,109 @@ Byte Range | Value | Meaning
16 - 19 | p_filesz | /* Segment size in file */
|-> seg_size | Needed for seg_size
| |
---------- | ---------- | ----------------------------------------------------
------------------------------------------------------------------------------
SUN Disk Label and boot images
for SUN SPARC
Sources:
cdrtools-2.01.01a77/mkisofs/sunlabel.h
cdrtools-2.01.01a77/mkisofs/mkisofs.8
by Joerg Schilling
The Disk Label is written to the first 512 bytes of the image. It can mark
8 partitions (slices ) of which the first contains the ISO image. The other
7 may contain boot images.
Words are composed big-endian style.
Boot images are provided externally. mkisofs arranges them after the end of
the ISO image so that each starts at a cylinder boundary (320 kB).
There is a mechanism in mkisofs which fills unused partitions by copies of
their predecessor in the partition table:
"If the special filename ... is used, the actual and all following
boot partitions are mapped to the previous partition.
If mkisofs is called with -G image -B ... all boot partitions are
mapped to the partition that contains the ISO9660 filesystem."
Disk Label components:
Byte Range | Value | Meaning
---------- | ---------- | ----------------------------------------------------
0 - 127 | label | ASCII Label
| | "CD-ROM Disc with Sun sparc boot created by ..."
| | mkisofs option -sparc-label
| |
128 - 263 | ========== | /* vtoc inclusions from AT&T SVr4 */
| |
128 - 131 | 1 | Layout version
132 - 139 | 0 | /* volume name */
140 - 141 | 8 | Number of partitions
| |
142 - 173 | ========== | 8 partition entries of 4 bytes
| |
142 - 145 | ========== | Entry for partition 1
142 - 143 | 4 | ID tag of partition: 4 = User partition
144 - 145 | 0x10 | Permissions: 0x10 = read-only
| |
146 - 149 | ========== | Entry for partition 2
146 - 147 | id_tag2 | ID tag of partition:
| | 0 = unused
| | 2 = Root partition with boot image
148 - 149 | perm2 | Permissions:
| | 0 = unused
| | 0x10 = read-only (if used)
| |
150 - 173 | ========== | Entries for partition 3 to 8.
| | See above: Entry for partition 2
| |
174 - 175 | 0 | Padding
| |
176 - 187 | 0 | /* info for mboot */
| |
188 - 191 | 0x600ddeee | /* to verify vtoc sanity */
| |
192 - 231 | 0 | Reserved
| |
232 - 263 | 0 | 8 Timestamps of yet unknown format
| |
264 - 419 | 0 | Padding
| |
420 - 443 | ========== | Disk properties
| |
420 - 421 | 350 | Rotations per minute
422 - 423 | 2048 | Number of physical cylinders (fixely 640 MB)
424 - 425 | 0 | /* alternates per cylinder */
426 - 429 | 0 | /* obsolete */
430 - 431 | 1 | /* interleave factor */
432 - 433 | 2048 | Number of data cylinders (fixely 640 MB)
434 - 435 | 0 | /* # of alternate cylinders */
436 - 437 | 1 | Number of heads per cylinder (i.e. 1 cyl = 320 kB)
438 - 439 | 640 | Number of sectors per head (i.e. 1 head = 320 kB)
440 - 443 | 0 | /* obsolete */
| |
444 - 507 | ========== | Partition table
| |
444 - 451 | ========== | Partition table entry #1
| |
444 - 447 | start_cyl | Start cylinder
| |
448 - 451 | num_blocks | Number of blocks in partition
| |
452 - 507 | ========== | Partition table entries #2 to #8
| ... | See above Partition table entry #1
| |
508 - 509 | 0xdabe | Magic Number
| |
510 - 511 | checksum | The result of exoring 2-byte words 0 to 254
| |
---------- | ---------- | ----------------------------------------------------
------------------------------------------------------------------------------