Commit a75c54f9 authored by Rusty Russell's avatar Rusty Russell Committed by Andi Kleen
Browse files

[PATCH] i386: i386 separate hardware-defined TSS from Linux additions 



On Thu, 2007-03-29 at 13:16 +0200, Andi Kleen wrote:
> Please clean it up properly with two structs.

Not sure about this, now I've done it.  Running it here.

If you like it, I can do x86-64 as well.

==
lguest defines its own TSS struct because the "struct tss_struct"
contains linux-specific additions.  Andi asked me to split the struct
in processor.h.

Unfortunately it makes usage a little awkward.

Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: default avatarAndi Kleen <ak@suse.de>
parent 82d1bb72

arch/i386/kernel/asm-offsets.c

+1 −1
Original line number Diff line number Diff line
@@ -93,7 +93,7 @@ void foo(void) 
	OFFSET(pbe_next, pbe, next);



	/* Offset from the sysenter stack to tss.esp0 */

	DEFINE(TSS_sysenter_esp0, offsetof(struct tss_struct, esp0) -

	DEFINE(TSS_sysenter_esp0, offsetof(struct tss_struct, x86_tss.esp0) -

		 sizeof(struct tss_struct));



	DEFINE(PAGE_SIZE_asm, PAGE_SIZE);

arch/i386/kernel/doublefault.c

+16 −13
Original line number Diff line number Diff line
@@ -33,7 +33,7 @@ static void doublefault_fn(void) 
		printk("double fault, tss at %08lx\n", tss);



		if (ptr_ok(tss)) {

			struct tss_struct *t = (struct tss_struct *)tss;

			struct i386_hw_tss *t = (struct i386_hw_tss *)tss;



			printk("eip = %08lx, esp = %08lx\n", t->eip, t->esp);
@@ -49,13 +49,15 @@ static void doublefault_fn(void) 
}



struct tss_struct doublefault_tss __cacheline_aligned = {

	.x86_tss = {

		.esp0		= STACK_START,

		.ss0		= __KERNEL_DS,

		.ldt		= 0,

		.io_bitmap_base	= INVALID_IO_BITMAP_OFFSET,



		.eip		= (unsigned long) doublefault_fn,

	.eflags		= X86_EFLAGS_SF | 0x2,	/* 0x2 bit is always set */

		/* 0x2 bit is always set */

		.eflags		= X86_EFLAGS_SF | 0x2,

		.esp		= STACK_START,

		.es		= __USER_DS,

		.cs		= __KERNEL_CS,
@@ -63,4 +65,5 @@ struct tss_struct doublefault_tss __cacheline_aligned = { 
		.ds		= __USER_DS,



		.__cr3		= __pa(swapper_pg_dir)

	}

};

arch/i386/kernel/ioport.c

+1 −1
Original line number Diff line number Diff line
@@ -114,7 +114,7 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) 
	 * Reset the owner so that a process switch will not set

	 * tss->io_bitmap_base to IO_BITMAP_OFFSET.

	 */

	tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;

	tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;

	tss->io_bitmap_owner = NULL;



	put_cpu();

arch/i386/kernel/process.c

+4 −4
Original line number Diff line number Diff line
@@ -375,7 +375,7 @@ void exit_thread(void) 
		t->io_bitmap_max = 0;

		tss->io_bitmap_owner = NULL;

		tss->io_bitmap_max = 0;

		tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET;

		tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET;

		put_cpu();

	}

}
@@ -554,7 +554,7 @@ static noinline void __switch_to_xtra(struct task_struct *next_p, 
		 * Disable the bitmap via an invalid offset. We still cache

		 * the previous bitmap owner and the IO bitmap contents:

		 */

		tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET;

		tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET;

		return;

	}
@@ -564,7 +564,7 @@ static noinline void __switch_to_xtra(struct task_struct *next_p, 
		 * matches the next task, we dont have to do anything but

		 * to set a valid offset in the TSS:

		 */

		tss->io_bitmap_base = IO_BITMAP_OFFSET;

		tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;

		return;

	}

	/*
@@ -576,7 +576,7 @@ static noinline void __switch_to_xtra(struct task_struct *next_p, 
	 * redundant copies when the currently switched task does not

	 * perform any I/O during its timeslice.

	 */

	tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;

	tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;

}



/*

arch/i386/kernel/sysenter.c

+3 −3
Original line number Diff line number Diff line
@@ -183,10 +183,10 @@ void enable_sep_cpu(void) 
		return;

	}



	tss->ss1 = __KERNEL_CS;

	tss->esp1 = sizeof(struct tss_struct) + (unsigned long) tss;

	tss->x86_tss.ss1 = __KERNEL_CS;

	tss->x86_tss.esp1 = sizeof(struct tss_struct) + (unsigned long) tss;

	wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0);

	wrmsr(MSR_IA32_SYSENTER_ESP, tss->esp1, 0);

	wrmsr(MSR_IA32_SYSENTER_ESP, tss->x86_tss.esp1, 0);

	wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) sysenter_entry, 0);

	put_cpu();	

}

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