>> Locate the file system buffer segment
##ln gdt_buffers
0138:000000a8 os2krnl:DOSGDTDATA:GDT_Buffers
##dw a8:0
00a8:00000000 ade4 94c4 0000 ff93 005a 0218 bc8b 0000
00a8:00000010 0664 0200 bc8c 000f 9000 00e5 0234 ade4
00a8:00000020 0000 0279 e05e 0000 0001 0400 0000 0000
00a8:00000030 0000 0000 46e5 4e49 3030 3630 4d54 2050
00a8:00000040 0000 0000 0000 0000 0000 b5cd 1f5e 3251
00a8:00000050 0400 0000 46e5 4e49 3030 3730 4d54 2050
00a8:00000060 0000 0000 0000 0000 0000 b5c8 1f5e 0000
00a8:00000070 0000 0000 4de5 3046 3030 2038 4d54 2050
##.d buf a8:ade4
buf_next: 001c buf_prev: ffff buf_freeLink: 0000
buf_flags: 02 buf_hVPB: 0279 buf_sector: 00000001
buf_tid: 00 buf_wrtcnt: 02 buf_wrtcntinc: 0096
buf_fill: 0000
##.d buf a8:234
buf_next: 044c buf_prev: 001c buf_freeLink: 0000
buf_flags: 04 buf_hVPB: 0279 buf_sector: 0000e05d
buf_tid: 00 buf_wrtcnt: 01 buf_wrtcntinc: 0000
buf_fill: 0000
##.d buf a8:44c
buf_next: 0664 buf_prev: 0234 buf_freeLink: 0000
buf_flags: 02 buf_hVPB: 0279 buf_sector: 0000001c
buf_tid: 00 buf_wrtcnt: 02 buf_wrtcntinc: 0096
buf_fill: 0000
##.d buf a8:664
buf_next: 087c buf_prev: 044c buf_freeLink: 0000
buf_flags: 04 buf_hVPB: 0279 buf_sector: 0000bcd4
buf_tid: 00 buf_wrtcnt: 01 buf_wrtcntinc: 0000
buf_fill: 0000
>> Find the volume these buffers are assigned to.
##ln gdt_vpb
0138:00000098 os2krnl:DOSGDTDATA:GDT_VPB
##.d vpb 98:279
vpb_flink: 01fe vpdFAT_cluster_mask: 07
vpb_blink: 02f4 vpdFAT_cluster_shift: 03
vpb_ref_count: 004e vpdFAT_first_FAT: 0001
vpb_search_count: 0000 vpdFAT_FAT_count: 02
vpb_first_access: 09 vpdFAT_root_entries: 0200
vpb_signature: 444a vpdFAT_first_sector: 0000014d
vpb_flags(2): 02:40 vpdFAT_max_cluster: 95f5
vpb_FSC: #0000:ff40 vpdFAT_FAT_size: 0096
vpi_ID: e2ea4414 vpdFAT_dir_sector: 0000012d
vpi_pDPB: #04b8:0038 vpdFAT_media: f8
vpi_cbSector: 0200 vpdFAT_next_free: 0000
vpi_totsec: 0004b0f0 vpdFAT_free_cnt: 63a8
vpi_trksec: 003f vpdFAT_FATentrysize: 10
vpi_nhead: 0010 vpdFAT_IDsector: 00000000
vpi_pDCS: #0000:0000 vpdFAT_access: 0000
vpi_pVCS: #0000:0000 vpdFAT_accwait: 0000
vpi_drive: 02 vpdFAT_pEASFT: #00d0:23da
vpi_unit: 02
vpi_text: DOS FAT
vpi_flags: 0003
>> The file system buffer segment is assigned a unique object owner
>> id.
##.m 0a8:0
*har par cpg va flg next prev link hash hob hal
0003 %feaef04c 00000400 %fe6ef000 001 0002 0023 0000 0000 0003 0000 =0000
hob har hobnxt flgs own hmte sown,cnt lt st xf
0003 0003 fec5 0000 ffec 0000 0000 00 01 00 00 vmkrhrw
pvmli cs eip phlock cpg va flg hptda hob sig csig
%fe82e4c4 002d 0a6800a5 %ac22403c 0001 %fe83c000 0005 024b 0003 ea9f ea9f
##dd %(a8:0)-10 l8
%fe702ff0 0b0c0001 4d5000a2 fe705854 0000cc99
%fe703000 94c4ade4 ff930000 0218005a 0000bc8b
##dd %(a8:0)-10-4+cc98 l8
%fe70fc84 00000000 00000000 ff9300a8 003ec010
%fe70fc94 ffa4000c fe80caac 00020100 ff9e0014
##.mo ff93
ff93 fsbuf
##
Notes:
File system buffers are allocated out of a buffer segment whose selector may be located either from the SAS File System section, offset +0xa or from symbol GDT_BUFFERS.
The buffer segment contains a header of length +0x1c.
Header Offset +0x0 gives the offset to the head of the list of most recently used buffers.
Header Offset +0x4 gives the offset to the tail of the list of most recently used buffers.
Each buffer contains a 0x18 byte header followed by 0x200 bytes of data. The buffer header is what is formatted by .D BUF.
For a description of the Buffer Header fields, see the File System Buffers in the System Reference.