search for: create_mbr_partition_table_entry

An evolution of the patch I posted yesterday to qemu-devel (https://www.mail-archive.com/qemu-devel@nongnu.org/msg588920.html) which (a) works and (b) has a test. Rich.

...e MBR code, but - * are not meant to be called from the main plugin. +/* Internal function for creating a single MBR PTE. The GPT code + * calls this for creating the protective MBR. */ -extern void create_mbr_partition_table (unsigned char *out) - __attribute__((__nonnull__ (1))); extern void create_mbr_partition_table_entry (const struct region *, bool bootable, int partition_id, unsigned char *) __attribute__((__nonnull__ (1, 4))); + +/* Create MBR or GPT layout. */ +extern void create_mbr_layout (void); extern void crea...

This is a revised version of the two series previously posted here: https://www.redhat.com/archives/libguestfs/2019-January/msg00137.html https://www.redhat.com/archives/libguestfs/2019-January/msg00139.html There have been many smaller changes but the highlights are: - Using SECTOR_SIZE instead of hard-coding 512 everywhere. - Additional safety checks that the EBR chain doesn't jump

...rt + 1); + if (i+1 < nr_regions) { + assert (regions[i].end + 1 == regions[i+1].start); + } + } + + return create_partition_table (); +} + +/* Create the partition table (and for GPT the secondary/backup). */ +static void create_mbr_partition_table (unsigned char *out); +static void create_mbr_partition_table_entry (const struct region *, int bootable, int partition_id, unsigned char *); +static void create_gpt_partition_header (const void *pt, int is_primary, unsigned char *out); +static void create_gpt_partition_table (unsigned char *out); +static void create_gpt_partition_table_entry (const struct region *...

...te__((__nonnull__ (1, 2))); /* Internal functions for creating MBR and GPT layouts. These are * published here because the GPT code calls into the MBR code, but * are not meant to be called from the main plugin. */ -extern void create_mbr_partition_table (unsigned char *out); -extern void create_mbr_partition_table_entry (const struct region *, int bootable, int partition_id, unsigned char *); +extern void create_mbr_partition_table (unsigned char *out) + __attribute__((__nonnull__ (1))); +extern void create_mbr_partition_table_entry (const struct region *, + int bootab...

nbdkit partitioning boot.img swap.img root.img ... creates a virtual disk by adding a partition table. In ancient times Xen used to do this. Rich.

The partitioning plugin patch is the same (except for rebasing). However I have changed the first two patches based on feedback received. In particular this fixes a very serious bug found by Eric Blake in the current truncate filter. Rich.

v1 was here: https://www.redhat.com/archives/libguestfs/2019-January/msg00008.html In v2 I have provided two patches: The first patch extends attribute((nonnull)) to most internal functions, but not to the external API. The second patch uses a macro so that attribute((format)) is only used in the public API on GCC or Clang. At least in theory these headers could be used by a C compiler which

...ut (void) */ eptr0 = find_ebr_region (3, &j); region.start = eptr0->start; - region.end = virtual_size (&regions) - 1; /* to end of disk */ + region.end = virtual_size (&the_regions) - 1; /* to end of disk */ region.len = region.end - region.start + 1; create_mbr_partition_table_entry (&region, false, 0xf, &primary[0x1ee]); @@ -144,8 +144,8 @@ find_file_region (size_t i, size_t *j) { const struct region *region; - for (; *j < nr_regions (&regions); ++(*j)) { - region = get_region (&regions, *j); + for (; *j < nr_regions (&the_regions); ++(*...

...reate_gpt_partition_header (disk, disk->pt, false, disk->secondary_header); + + return 0; +} + +static void +chs_too_large (unsigned char *out) +{ + const int c = 1023, h = 254, s = 63; + + out[0] = h; + out[1] = (c & 0x300) >> 2 | s; + out[2] = c & 0xff; +} + +static void +create_mbr_partition_table_entry (const struct region *region, + bool bootable, int partition_id, + unsigned char *out) +{ + uint64_t start_sector, nr_sectors; + uint32_t u32; + + assert (IS_ALIGNED (region->start, SECTOR_SIZE)); + + start_sector = region-&gt...

...reate_gpt_partition_header (disk, disk->pt, false, disk->secondary_header); + + return 0; +} + +static void +chs_too_large (unsigned char *out) +{ + const int c = 1023, h = 254, s = 63; + + out[0] = h; + out[1] = (c & 0x300) >> 2 | s; + out[2] = c & 0xff; +} + +static void +create_mbr_partition_table_entry (const struct region *region, + bool bootable, int partition_id, + unsigned char *out) +{ + uint64_t start_sector, nr_sectors; + uint32_t u32; + + assert (IS_ALIGNED (region->start, SECTOR_SIZE)); + + start_sector = region-&gt...

For v3 I reimplemented this using mke2fs -d. This obviously makes the implementation a whole lot simpler, but cannot support multiple directory merging. Patches 1-3 are the same as before. I've also reproduced the notes from v2 below. v2: - Fix inconsistent tab/space. - All 3 plugins now contain a block of text pointing to the other 2 plugins. - TMDIR -> TMPDIR - Unlink the

Another interesting thing you can do with this plugin: https://rwmj.wordpress.com/2019/02/19/nbdkit-linuxdisk-plugin/ v2: - Fix inconsistent tab/space. - All 3 plugins now contain a block of text pointing to the other 2 plugins. - TMDIR -> TMPDIR - Unlink the temporary file and other cleanups along error paths. - fclose -> pclose, and check the return value for errors. -

Turns out Japanese trains are good for coding! In supermin we have a bunch of code to create the libguestfs appliance. It creates it directly using libext2fs (part of e2fsprogs). We can use the same technique to create ext2 virtual disks in nbdkit, which is what this new plugin does. Why a new plugin instead of modifying the floppy plugin? See the 4/4 commit message for an explanation. The

This was a rather longer trip around the houses than I anticipated! The basic purpose of the patch series is to set $nbdkit_stdio_safe to "0" or "1" in sh and eval plugin scripts. To do that, I ended up adding a nicer way to manipulate environ lists, and to do that, I ended up adding a whole generic vector implementation which is applicable in a lot of different places.