ra8_fs_fmt_geom_t Struct Reference

Computed on-disk geometry for one ra8_fs_format() run. More...

#include <ra8_fs_fat_types_internal.h>

Data Fields
ra8_fs_type_t	type
	Resolved FAT variant.
uint64_t	total_sectors
	Whole-device sector count.
uint32_t	bytes_per_sector
	Device sector size in bytes.
uint32_t	sectors_per_cluster
	Chosen cluster size (sectors).
uint32_t	reserved_sectors
	Boot + (FAT32) FSInfo/backup region.
uint32_t	fat_size_sectors
	Sectors per FAT copy.
uint32_t	root_entries
	FAT12/16 root entries (0 on FAT32).
uint32_t	root_sectors
	FAT12/16 fixed-root sector span.
uint32_t	count_of_clusters
	Resulting data-region cluster count.

Detailed Description

Computed on-disk geometry for one ra8_fs_format() run.

Filled by priv_fmt_choose_geometry() from the requested type and the backend capacity, then consumed by the BPB / FAT writers. All counts are in DEVICE sectors of bytes_per_sector bytes.

Invariant

sectors_per_cluster is a power of two in 1..k_fmt_spc_max.

count_of_clusters lands in the band valid for type.

bytes_per_sector is a power of two in 512..4096.

Definition at line 794 of file ra8_fs_fat_types_internal.h.

Field Documentation

bytes_per_sector

uint32_t ra8_fs_fmt_geom_t::bytes_per_sector

Device sector size in bytes.

Definition at line 797 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_build_bpb_f16(), internal_fmt_build_bpb_f32(), internal_fmt_clusters_for(), internal_fmt_seed_fats(), internal_fmt_write_fsinfo(), priv_fmt_choose_geometry(), and priv_fmt_emit_volume().

count_of_clusters

uint32_t ra8_fs_fmt_geom_t::count_of_clusters

Resulting data-region cluster count.

Definition at line 803 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_write_fsinfo(), and priv_fmt_choose_geometry().

fat_size_sectors

uint32_t ra8_fs_fmt_geom_t::fat_size_sectors

Sectors per FAT copy.

Definition at line 800 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_seed_fats(), internal_fmt_write_totals(), priv_fmt_choose_geometry(), and priv_fmt_emit_volume().

reserved_sectors

uint32_t ra8_fs_fmt_geom_t::reserved_sectors

Boot + (FAT32) FSInfo/backup region.

Definition at line 799 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_build_bpb_f16(), internal_fmt_build_bpb_f32(), internal_fmt_clusters_for(), internal_fmt_seed_fats(), and priv_fmt_emit_volume().

root_entries

uint32_t ra8_fs_fmt_geom_t::root_entries

FAT12/16 root entries (0 on FAT32).

Definition at line 801 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_build_bpb_f16().

root_sectors

uint32_t ra8_fs_fmt_geom_t::root_sectors

FAT12/16 fixed-root sector span.

Definition at line 802 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_clusters_for(), and priv_fmt_emit_volume().

sectors_per_cluster

uint32_t ra8_fs_fmt_geom_t::sectors_per_cluster

Chosen cluster size (sectors).

Definition at line 798 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_build_bpb_f16(), internal_fmt_build_bpb_f32(), priv_fmt_choose_geometry(), and priv_fmt_emit_volume().

total_sectors

uint64_t ra8_fs_fmt_geom_t::total_sectors

Whole-device sector count.

Definition at line 796 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_build_bpb_f16(), internal_fmt_build_bpb_f32(), internal_fmt_clusters_for(), internal_fmt_write_totals(), and priv_fmt_choose_geometry().

type

ra8_fs_type_t ra8_fs_fmt_geom_t::type

Resolved FAT variant.

Definition at line 795 of file ra8_fs_fat_types_internal.h.

Referenced by internal_fmt_build_bpb_f16(), internal_fmt_clusters_for(), internal_fmt_seed_fats(), internal_fmt_write_fsinfo(), internal_fmt_write_totals(), internal_format_locked(), priv_fmt_choose_geometry(), and priv_fmt_emit_volume().

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The documentation for this struct was generated from the following file:

• libs/ra8_fs/src/ra8_fs_fat_types_internal.h