SCSI_GET_VPD_PAGE(9) SCSI mid layer SCSI_GET_VPD_PAGE(9)NAME
scsi_get_vpd_page - Get Vital Product Data from a SCSI device
SYNOPSIS
int scsi_get_vpd_page(struct scsi_device * sdev, u8 page, unsigned char * buf, int buf_len);
ARGUMENTS
sdev
The device to ask
page
Which Vital Product Data to return
buf
where to store the VPD
buf_len
number of bytes in the VPD buffer area
DESCRIPTION
SCSI devices may optionally supply Vital Product Data. Each 'page' of VPD is defined in the appropriate SCSI document (eg SPC, SBC). If the
device supports this VPD page, this routine returns a pointer to a buffer containing the data from that page. The caller is responsible for
calling kfree on this pointer when it is no longer needed. If we cannot retrieve the VPD page this routine returns NULL.
AUTHORS
James Bottomley <James.Bottomley@hansenpartnership.com>
Author.
Rob Landley <rob@landley.net>
Author.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 SCSI_GET_VPD_PAGE(9)
Check Out this Related Man Page
SG_VPD(8) SG3_UTILS SG_VPD(8)NAME
sg_vpd - fetches Vital Product Data (VPD) pages using a SCSI INQUIRY command
SYNOPSIS
sg_vpd [--enumerate] [--help] [--hex] [--ident] [--long] [--maxlen=LEN] [--page=PG] [--quiet] [--raw] [--verbose] [--version] DEVICE
DESCRIPTION
This utility fetches a Vital Product Data page and decodes it or outputs it in ASCII hexadecimal or binary. VPD pages are fetched with a
SCSI INQUIRY command.
Probably the most important page is the Device Identification VPD page (page number: 0x83). Since SPC-3, support for this page has been
flagged as mandatory. This page can be fetched by using the --ident option.
When no options are given, other than a DEVICE, then the "Supported VPD pages" (0x0) VPD page is fetched and decoded.
OPTIONS
Arguments to long options are mandatory for short options as well. The options are arranged in alphabetical order based on the long option
name.
-e, --enumerate
list the names of the known VPD pages, first the standard pages, then the vendor specific pages. Each group is sorted in abbrevia-
tion order. The DEVICE and other options are ignored and this utility exits afte listing the VPD page names.
-h, --help
outputs the usage message summarizing command line options then exits. Ignores DEVICE if given.
-H, --hex
outputs the requested VPD page in ASCII hexadecimal. Can be used multiple times, see section on the ATA information vpd page.
-i, --ident
decode the device identification (0x83) VPD page. When used once this option has the same effect as '--page=di'. When use twice then
the short form of the device identification VPD page's logical unit designator is decoded. In the latter case this option has the
same effect as '--quiet --page=di_lu'.
-l, --long
when decoding some VPD pages, give a little more output. For example the ATA Information VPD page only shows the signature (in hex)
and the IDENTIFY (PACKET) DEVICE (in hex) when this option is given.
-m, --maxlen=LEN
where LEN is the (maximum) response length in bytes. It is placed in the cdb's "allocation length" field. If not given (or LEN is
zero) then 252 is used (apart from the ATA Information VPD page which defaults to 572) and, if the response indicates this value is
insufficient, another INQUIRY command is sent with a larger value in the cdb's "allocation length" field. If this option is given
and LEN is greater than 0 then only one INQUIRY command is sent. Since many simple devices implement the INQUIRY command badly (and
do not support VPD pages) then the safest value to use for LEN is 36. See the sg_inq man page for the more information.
-p, --page=PG
where PG is the VPD page to be decoded or output. The PG argument can either be an abbreviation, a number or a pair or numbers sepa-
rated by a comma. The VPD page abbreviations can be seen by using the --enumerate option. If a number is given it is assumed to be
decimal unless it has a hexadecimal indicator which is either a leading '0x' or a trailing 'h'. If one number is given then it is
assumed to be a VPD page number. If two numbers are given the second number indicates which vendor specific VPD page to decode when
several pages share the same VPD page number. If this option is not given (nor '-i', '-l' nor '-V') then the "Supported VPD pages"
(0x0) VPD page is fetched and decoded.
-q, --quiet
suppress the amount of decoding output.
-r, --raw
output requested VPD page in binary. The output should be piped to a file or another utility when this option is used. The binary is
sent to stdout, and errors are sent to stderr.
-v, --verbose
increases the level or verbosity.
-V, --version
print out version string then exit.
ATA INFORMATION VPD PAGE
This VPD page (0x89 or 'ai') is defined by the SCSI to ATA Translation standard. It contains information about the SAT layer, the "signa-
ture" of the ATA device and the response to the ATA IDENTIFY (PACKET) DEVICE command. The latter part has 512 bytes of identity, capability
and settings data which the hdparm utility is capable of decoding (so this utility doesn't decode it).
To unclutter the output for this page, the signature and the IDENTIFY (PACKET) DEVICE response are not output unless the --long option (or
--hex or --raw) are given. When the --long option is given the IDENTIFY (PACKET) DEVICE response is output as 256 (16 bit) words as is the
fashion for ATA devices. To see that response as a string of bytes use the '-HH' option. To format the output suitable for hdparm to decode
use either the '-HHH' or '-rr' option. For example if 'dev/sdb' is a SATA disk behind a SAT layer then this command: 'sg_vpd -p ai -HHH
/dev/sdb | hdparm --Istdin' should decode the ATA IDENTIFY (PACKET) DEVICE response.
NOTES
In the 2.4 series of Linux kernels the DEVICE must be a SCSI generic (sg) device. In the 2.6 series block devices (e.g. disks and ATAPI
DVDs) can also be specified. For example "sg_inq /dev/sda" will work in the 2.6 series kernels. From lk 2.6.6 other SCSI "char" device
names may be used as well (e.g. "/dev/st0m").
EXIT STATUS
The exit status of sg_vpd is 0 when it is successful. Otherwise see the sg3_utils(8) man page.
AUTHOR
Written by Doug Gilbert
REPORTING BUGS
Report bugs to <dgilbert at interlog dot com>.
COPYRIGHT
Copyright (C) 2006-2008 Douglas Gilbert
This software is distributed under a FreeBSD license. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR-
POSE.
SEE ALSO
sg_inq(sg3_utils), sdparm(sdparm), hdparm(hdparm)
sg3_utils-1.26 February 2008 SG_VPD(8)