Documentation
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Index ¶
- func DumpGPTVMDKDescriptor(w io.Writer, cid uint32, layout Layout, headerPath, padFile string) error
- func DumpGPTVMDKDescriptorToFile(vmdkPath string, cid uint32, devices []string) error
- func DumpVMDKDescriptor(w io.Writer, cid uint32, devices []string) error
- func DumpVMDKDescriptorToFile(vmdkdesc string, cid uint32, devices []string) error
- type Layout
- type Partition
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func DumpGPTVMDKDescriptor ¶ added in v0.2.0
func DumpGPTVMDKDescriptor(w io.Writer, cid uint32, layout Layout, headerPath, padFile string) error
DumpGPTVMDKDescriptor writes a VMDK descriptor whose virtual disk is a GPT-partitioned image with one partition per layout.Partitions entry.
headerPath should reference a 34-sector blob produced by Layout.WriteHeader covering LBAs 0..33 (protective MBR, primary GPT header, primary entry array).
When padFile is empty, padding regions are emitted as "RW <count> ZERO" extents. Otherwise padFile must be a zero-filled file of at least max padding-region size; padding regions are emitted as FLAT extents reading from offset 0 of padFile.
func DumpGPTVMDKDescriptorToFile ¶ added in v0.2.0
DumpGPTVMDKDescriptorToFile generates a GPT-partitioned VMDK at vmdkPath that references the supplied erofs layer files as separate partitions on a single virtual disk. A header blob and (when ZERO extents are not in use) a shared padding file are written next to vmdkPath; no secondary GPT is written since the disk is synthetic and read-only.
The vmdk filename's extension is replaced with "_header.bin" and "_pad.bin" suffixes to derive the auxiliary filenames; e.g. for "/x/merged_fs_gpt.vmdk" the auxiliary files are "/x/merged_fs_gpt_header.bin" and (if applicable) "/x/merged_fs_gpt_pad.bin".
func DumpVMDKDescriptor ¶
DumpVMDKDescriptor writes a monolithicFlat VMDK descriptor to w. Extent path strings are written verbatim from devices.
Types ¶
type Layout ¶ added in v0.2.0
type Layout struct {
SectorSize uint64
AlignSectors uint64
TotalSectors uint64
DiskGUID [16]byte
Partitions []Partition
}
Layout describes the GPT layout for a list of erofs layer files.
func ComputeLayout ¶ added in v0.2.0
ComputeLayout builds a GPT Layout for the supplied erofs layer files. The first path becomes partition 1, the second becomes partition 2, and so on. Layer file sizes are read via os.Stat.
func (Layout) FirstUsableLBA ¶ added in v0.2.0
FirstUsableLBA returns the first LBA available for partition data.
func (Layout) LastUsableLBA ¶ added in v0.2.0
LastUsableLBA returns the last LBA available for partition data.
func (Layout) WriteHeader ¶ added in v0.2.0
WriteHeader writes the protective MBR + primary GPT header + primary partition entry array, totalling gptReservedSectors (34) sectors. The secondary GPT is omitted: this disk is synthetic and read-only, so backup recovery is not needed.
type Partition ¶ added in v0.2.0
type Partition struct {
GUID [16]byte
TypeGUID [16]byte
FirstLBA uint64
LastLBA uint64
Name string
Source string
SizeBytes uint64
}
Partition describes a single GPT partition slot for an erofs layer.
func (Partition) SectorCount ¶ added in v0.2.0
SectorCount returns the number of 512-byte sectors covered by the partition.
Source Files