Date: Tue, 12 Jan 1999 21:00:01 -0800 (PST) From: Andrew Sherrod <yaldabaoth@geocities.com> To: freebsd-bugs@FreeBSD.ORG Subject: Re: i386/9431: wd.c Does nto recognize certain LBA disks [patch attached] Message-ID: <199901130500.VAA10098@freefall.freebsd.org>
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The following reply was made to PR i386/9431; it has been noted by GNATS.
From: Andrew Sherrod <yaldabaoth@geocities.com>
To: freebsd-gnats-submit@freebsd.org, ixkatl@yahoo.com
Cc:
Subject: Re: i386/9431: wd.c Does nto recognize certain LBA disks [patch attached]
Date: Tue, 12 Jan 1999 23:53:21 -0500
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Having looked into this further, it seems that the following is a better
set of patches.
Basically, if the user specifies flags, then they are used. If not (for
example when doing an initial installation) the
BIOS flags are used to determine whether LBA is supported. Thus, for
some BIOSes which do not report
the correct CHS values, the LBA value will be used instead. This seems
to eliminate the need to use a DOS
partition to establish geometry on my Award BIOS. (version 4.51PG). (And
I have heard of many problems
getting correct disk geometry from newer Award BIOSes, so I do not think
I am alone.In fact, just
check the number of FAQs regarding incorrect reporting of disk
geometry.)
It should not break any current software, as the user can override it in
a kernel configuration.
(If the user wants to set no options, but still not use BIOS flags, set
options equal to 0x8000 or 0x4000, which are both unused reserved bits,
per ASC X3T10 Working Draft X3T10/0948D). If necessary, these values
could be #defined as (for example) WDOPT_NOBIOS or somthing similar, to
make it easier for the user to
disable the BIOS flags. (This could even be the default, with a comment
instructing the user on how to
enable BIOS flags for certain BIOSes, though initial installation should
probably use BIOS flags, as
the user can't set options prior to installation.)
The only problem I can forsee is that for older drives/BIOSes these
flags may not be set properly, or may return
meaningless values. However, as some newer drives/BIOSes give
meaningless CHS values when these flags
are not used, it seems to me it is a trade-off between supporting the
quirks of older drives and BIOSes and the quirks of newer drives and
BIOSes.
Well, let me know if there are any other problems with these changes. I
am still digging through the kernel code, so
I am well aware that there is a huge body of code about which I know
little or nothing. So any input is appreciated.
Thanks.
Andrew Sherrod
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*** wd.c.2_2_8 Tue Jan 12 23:40:13 1999
--- wd.c.original.2_2_8 Mon Jan 11 20:41:01 1999
***************
*** 112,119 ****
#define WDOPT_SLEEPHACK 0x4000
#define WDOPT_FORCEHD(x) (((x)&0x0f00)>>8)
#define WDOPT_MULTIMASK 0x00ff
! #define WDOPT_LBA 0x0200
!
/*
* This biotab field doubles as a field for the physical unit number on
* the controller.
--- 112,118 ----
#define WDOPT_SLEEPHACK 0x4000
#define WDOPT_FORCEHD(x) (((x)&0x0f00)>>8)
#define WDOPT_MULTIMASK 0x00ff
!
/*
* This biotab field doubles as a field for the physical unit number on
* the controller.
***************
*** 1686,1710 ****
}
bcopy(tb, wp, sizeof(struct wdparams));
!
! /* If user has not defined du->cfg_flags (eg.
! if they are doing a new install) then use actual
! BIOS flags. This should allow kernel to pick up
! the actual disk geometry without recourse to
! the DOS partition work-around. -A. Sherrod 01/12/1999*/
!
! /* NOTE: This DOES NOT require the drive to use the LBA
! addressing. It only means that for certain difficult
! BIOSes (e.g. Award), large disks will report the
! correct disk size. (As CHS does not give the correct
! number of sectors while LBA size does) */
!
! if(!du->cfg_flags){
! du->cfg_flags=wp->wdp_capability;
! du->cfg_flags=du->cfg_flags<<8;
! du->cfg_flags+=wp->wdp_cap_validate;
! }
!
/* shuffle string byte order */
for (i = 0; i < sizeof(wp->wdp_model); i += 2) {
u_short *p;
--- 1685,1691 ----
}
bcopy(tb, wp, sizeof(struct wdparams));
!
/* shuffle string byte order */
for (i = 0; i < sizeof(wp->wdp_model); i += 2) {
u_short *p;
***************
*** 1746,1754 ****
du->dk_dd.d_nsectors = wp->wdp_sectors;
du->dk_dd.d_secpercyl = du->dk_dd.d_ntracks * du->dk_dd.d_nsectors;
du->dk_dd.d_secperunit = du->dk_dd.d_secpercyl * du->dk_dd.d_ncylinders;
! #line 1
! if (((wp->wdp_cylinders == 16383)||
! (du->cfg_flags&WDOPT_LBA)) &&
du->dk_dd.d_secperunit < wp->wdp_lbasize) {
du->dk_dd.d_secperunit = wp->wdp_lbasize;
du->dk_dd.d_ncylinders =
--- 1727,1733 ----
du->dk_dd.d_nsectors = wp->wdp_sectors;
du->dk_dd.d_secpercyl = du->dk_dd.d_ntracks * du->dk_dd.d_nsectors;
du->dk_dd.d_secperunit = du->dk_dd.d_secpercyl * du->dk_dd.d_ncylinders;
! if (wp->wdp_cylinders == 16383 &&
du->dk_dd.d_secperunit < wp->wdp_lbasize) {
du->dk_dd.d_secperunit = wp->wdp_lbasize;
du->dk_dd.d_ncylinders =
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*** wd.c.3_0 Tue Jan 12 23:39:32 1999
--- wd.c.original.3_0 Tue Jan 12 22:22:52 1999
***************
*** 1861,1885 ****
}
bcopy(tb, wp, sizeof(struct wdparams));
!
! /*If user has not defined cfg_flags (eg. if they are doing
! a new install) then use actual BIOS flags. This should allow
! kernel to pick up the actual disk geometry without
! recourse to the DOS partition work-around.
! -A. Sherrod 01/12/1999 */
!
! /* NOTE: This DOES NOT require the drive to use the LBA
! addressing. It only means that for certain difficult
! BIOSes (e.g. Award), large disks will report the
! correct disk size. (As CHS does not give the correct
! number of sectors while LBA size does.) */
!
! if(!du->cfg_flags){
! du->cfg_flags=wp->wdp_capability;
! du->cfg_flags=du->cfg_flags<<8;
! du->cfg_flag+=wp->wdp_cap_validate;
! }
!
/* shuffle string byte order */
for (i = 0; (unsigned)i < sizeof(wp->wdp_model); i += 2) {
u_short *p;
--- 1861,1867 ----
}
bcopy(tb, wp, sizeof(struct wdparams));
!
/* shuffle string byte order */
for (i = 0; (unsigned)i < sizeof(wp->wdp_model); i += 2) {
u_short *p;
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