Improved handling of cylinder alignment if the resulting image size

size is not divisible by 2048. Old behavior was to not align. New is
to pad up by a few blocks of 512 bytes.
release-1.5.4.branch
Thomas Schmitt 8 years ago
parent 5a3d84cbbb
commit c47167058a
  1. 4
      doc/susp_aaip_isofs_names.txt
  2. 1
      libisofs/ecma119.c
  3. 6
      libisofs/ecma119.h
  4. 3
      libisofs/make_isohybrid_mbr.c
  5. 30
      libisofs/system_area.c

@ -128,7 +128,7 @@ Name:
Purpose:
Records the IsoHfsplusBlessings blessing of a IsoNode as defined
in libisofs.h. At image load time, this info shall be converted back
in libisofs.h. At image load time, this info may be converted back
into a relation between IsoImage and IsoNode so that it is available for
the HFS+ writer when a new ISO 9660 / HFS+ image gets produced.
@ -152,7 +152,7 @@ Name:
Purpose:
Records the iso_hfsplus_xinfo_data information as defined in libisofs.h.
At image load time, this info shall be converted back into an xinfo
At image load time, this info may be converted back into an xinfo
attachment for iso_hfsplus_xinfo_func so that it is available for
the HFS+ writer when a new ISO 9660 / HFS+ image gets produced.

@ -2481,6 +2481,7 @@ int ecma119_image_new(IsoImage *src, IsoWriteOpts *in_opts, Ecma119Image **img)
target->wthread_is_running = 0;
target->post_iso_part_pad = 0;
target->prep_part_size = 0;
target->efi_boot_part_size = 0;
target->efi_boot_part_filesrc = NULL;

@ -798,6 +798,12 @@ struct ecma119_image
struct iso_mbr_partition_request *mbr_req[ISO_MBR_ENTRIES_MAX];
int mbr_req_count;
/* Number of bytes which have to be added after the cylinder aligned end
of the overall ISO partition because clinder size is not a multiple
of 2048
*/
int post_iso_part_pad;
uint32_t prep_part_size;
/* GPT description. To be composed during IsoImageWriter

@ -590,7 +590,8 @@ int make_isolinux_mbr(uint32_t *img_blocks, Ecma119Image *t,
part_offset = 1;
}
hd_img_blocks = ((off_t) *img_blocks) * (off_t) 4;
hd_img_blocks = ((off_t) *img_blocks) * (off_t) 4 -
t->post_iso_part_pad / 512;
boot_lba = t->bootsrc[0]->sections[0].block;
head_count = t->partition_heads_per_cyl;

@ -329,21 +329,24 @@ int make_grub_msdos_label(uint32_t img_blocks, int sph, int hpc,
/* @param flag bit0= zeroize partitions entries 2, 3, 4
bit0= UEFI protective MBR: start LBA = 1
bit1= UEFI protective MBR: start LBA = 1
*/
static
int iso_offset_partition_start(uint32_t img_blocks, uint32_t partition_offset,
int iso_offset_partition_start(uint32_t img_blocks, int post_part_pad,
uint32_t partition_offset,
int sph, int hpc, uint8_t *buf, int flag)
{
uint8_t *wpt;
uint32_t end_lba, end_sec, end_head, end_cyl;
uint32_t start_lba, start_sec, start_head, start_cyl;
uint64_t img_hd_blocks;
int i;
iso_compute_cyl_head_sec((uint64_t) partition_offset, hpc, sph,
&start_lba, &start_sec, &start_head, &start_cyl, 1);
iso_compute_cyl_head_sec((uint64_t) img_blocks, hpc, sph,
&end_lba, &end_sec, &end_head, &end_cyl, 0);
img_hd_blocks = ((uint64_t) img_blocks) * 4 - post_part_pad / 512;
iso_compute_cyl_head_sec(img_hd_blocks, hpc, sph,
&end_lba, &end_sec, &end_head, &end_cyl, 2);
if (flag & 2) {
start_lba = 1;
start_sec = 2;
@ -1863,10 +1866,10 @@ int iso_write_system_area(Ecma119Image *t, uint8_t *buf)
return ret;
} else if (t->opts->partition_offset == 0) {
/* Re-write partion entry 1 : start at 0, type Linux */
ret = write_mbr_partition_entry(1, 0x83,
(uint64_t) 0, (uint64_t) img_blocks,
blk = ((uint64_t) img_blocks) * 4 - t->post_iso_part_pad / 512;
ret = write_mbr_partition_entry(1, 0x83, (uint64_t) 0, blk,
t->partition_secs_per_head, t->partition_heads_per_cyl,
buf, 0);
buf, 2);
if (ret < 0)
return ret;
}
@ -1884,7 +1887,7 @@ int iso_write_system_area(Ecma119Image *t, uint8_t *buf)
} else {
mbrp1_blocks = img_blocks;
}
ret = iso_offset_partition_start(mbrp1_blocks,
ret = iso_offset_partition_start(mbrp1_blocks, t->post_iso_part_pad,
t->opts->partition_offset,
t->partition_secs_per_head,
t->partition_heads_per_cyl, buf,
@ -1936,7 +1939,7 @@ int iso_write_system_area(Ecma119Image *t, uint8_t *buf)
/* Choose *heads_per_cyl so that
- *heads_per_cyl * secs_per_head * 1024 >= imgsize / 512
- *heads_per_cyl * secs_per_head is divisible by 4
- it is as small as possible (to reduce aligment overhead)
- it is as small as possible (to reduce alignment overhead)
- it is <= 255
@return 1= success , 0= cannot achieve goals
*/
@ -2053,14 +2056,15 @@ int iso_align_isohybrid(Ecma119Image *t, int flag)
frac = imgsize - ((off_t) img_blocks) * (off_t) 2048;
if (frac == 0)
{ret = ISO_SUCCESS; goto ex;}
t->post_iso_part_pad = 0;
if (frac % 2048) {
t->post_iso_part_pad = 2048 - frac % 2048;
sprintf(msg,
"Cylinder size %d not divisible by 2048. Cannot align partition.",
(int) cylsize);
"Cylinder aligned image size is not divisible by 2048. Have to add %d bytes.",
t->post_iso_part_pad);
iso_msgs_submit(0, msg, 0, "WARNING", 0);
} else {
t->opts->tail_blocks += frac / 2048;
}
t->opts->tail_blocks += (frac + 2047) / 2048;
ret = ISO_SUCCESS;
ex:;
LIBISO_FREE_MEM(msg);

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