similar to: [PATCH 5/21] i386 Pnp byte granularity

PnP BIOS data, code, and 32-bit entry segments all have fixed limits as well; set them in the GDT rather than adding more code. It would be nice to add these fixups to the boot GDT rather than setting the GDT for each CPU; perhaps I can wiggle this in later, but getting it in before the subsys init looks tricky. Also, make some progress on deprecating the ugly Q_SET_SEL macros. Signed-off-by:

PnP BIOS data, code, and 32-bit entry segments all have fixed limits as well; set them in the GDT rather than adding more code. It would be nice to add these fixups to the boot GDT rather than setting the GDT for each CPU; perhaps I can wiggle this in later, but getting it in before the subsys init looks tricky. Also, make some progress on deprecating the ugly Q_SET_SEL macros. Signed-off-by:

It is impossible to have a zero length segment in descriptor tables using "normal" segments. One of many ways to properly protect segments to zero length is to map the base to an umapped page. Create a nicer way to do this, and stop subtracting 1 from the length passed to set_limit (note calling set limit with a zero limit does something very bad! - not anymore). Signed-off-by:

It is impossible to have a zero length segment in descriptor tables using "normal" segments. One of many ways to properly protect segments to zero length is to map the base to an umapped page. Create a nicer way to do this, and stop subtracting 1 from the length passed to set_limit (note calling set limit with a zero limit does something very bad! - not anymore). Signed-off-by:

Found some stray descriptor table accessors that had non-optimal assembler constraints. Use "q" to get word, high and low byte access without forcing a specific register constraint. Add desc as a memory output operand. Also, get_base was completely unused. Deprecate it. The function get_limit is also unused, but I did not deprecate it; it could be used in arch/i386/mm/fault.c.

Found some stray descriptor table accessors that had non-optimal assembler constraints. Use "q" to get word, high and low byte access without forcing a specific register constraint. Add desc as a memory output operand. Also, get_base was completely unused. Deprecate it. The function get_limit is also unused, but I did not deprecate it; it could be used in arch/i386/mm/fault.c.

Found some stray descriptor table accessors that had non-optimal assembler constraints. Use "q" to get word, high and low byte access without forcing a specific register constraint. Add desc as a memory output operand. Also, get_base was completely unused. Deprecate it. The function get_limit is also unused, but I did not deprecate it; it could be used in arch/i386/mm/fault.c.

Found some stray descriptor table accessors that had non-optimal assembler constraints. Use "q" to get word, high and low byte access without forcing a specific register constraint. Add desc as a memory output operand. Also, get_base was completely unused. Deprecate it. The function get_limit is also unused, but I did not deprecate it; it could be used in arch/i386/mm/fault.c.

Old accessors to fetch LDT descriptors are unused and outdated and in the wrong header file. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/include/asm-i386/system.h =================================================================== --- linux-2.6.14-zach-work.orig/include/asm-i386/system.h 2005-11-04 17:45:04.000000000 -0800 +++

Old accessors to fetch LDT descriptors are unused and outdated and in the wrong header file. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/include/asm-i386/system.h =================================================================== --- linux-2.6.14-zach-work.orig/include/asm-i386/system.h 2005-11-04 17:45:04.000000000 -0800 +++

Ancient inline assembler that manipulates descriptor tables is unreadable and has no type checking. Doing this in C actually generates better code, saves code space, and improves readability. The fact that you must cast descriptors to (char *) for the inline assembler to work properly caused me no end of grief working on these patches. Note that GCC does not generate rotations to utilize

Ancient inline assembler that manipulates descriptor tables is unreadable and has no type checking. Doing this in C actually generates better code, saves code space, and improves readability. The fact that you must cast descriptors to (char *) for the inline assembler to work properly caused me no end of grief working on these patches. Note that GCC does not generate rotations to utilize

Since APM BIOS segment limits are now fixed, set them in head.S GDT and don't use the complicated _set_limit() macro expansion. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/head.S =================================================================== --- linux-2.6.14-zach-work.orig/arch/i386/kernel/head.S 2005-11-04 15:46:11.000000000 -0800

Since APM BIOS segment limits are now fixed, set them in head.S GDT and don't use the complicated _set_limit() macro expansion. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.14-zach-work/arch/i386/kernel/head.S =================================================================== --- linux-2.6.14-zach-work.orig/arch/i386/kernel/head.S 2005-11-04 15:46:11.000000000 -0800

i386 Transparent paravirtualization subarch patch #5 This change encapsulates descriptor and task register management. Diffs against: 2.6.13-rc4-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-08 17:31:59.000000000 -0700

i386 Transparent paravirtualization subarch patch #5 This change encapsulates descriptor and task register management. Diffs against: 2.6.13-rc4-mm1 Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/desc.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/desc.h 2005-08-08 17:31:59.000000000 -0700

Move base / limit accessors into desc.h, where they properly belong. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/system.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/system.h 2005-08-08 17:58:03.000000000 -0700 +++ linux-2.6.13/include/asm-i386/system.h 2005-08-08 18:01:31.000000000 -0700

Move base / limit accessors into desc.h, where they properly belong. Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/system.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/system.h 2005-08-08 17:58:03.000000000 -0700 +++ linux-2.6.13/include/asm-i386/system.h 2005-08-08 18:01:31.000000000 -0700

Move base / limit accessors into desc.h, where they properly belong. Patch-base: 2.6.13-rc5-mm1 Patch-keys: i386 desc cleanup Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/system.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/system.h 2005-08-09 20:17:26.000000000 -0700 +++

Move base / limit accessors into desc.h, where they properly belong. Patch-base: 2.6.13-rc5-mm1 Patch-keys: i386 desc cleanup Signed-off-by: Zachary Amsden <zach@vmware.com> Index: linux-2.6.13/include/asm-i386/system.h =================================================================== --- linux-2.6.13.orig/include/asm-i386/system.h 2005-08-09 20:17:26.000000000 -0700 +++