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@@ -4,7 +4,6 @@
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#include <asm/asm-offsets.h>
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#include <asm/thread_info.h>
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#include <asm/processor-flags.h>
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-#include <asm/pgtable.h>
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/*G:020
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* Our story starts with the kernel booting into startup_32 in
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@@ -38,113 +37,9 @@ ENTRY(lguest_entry)
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/* Set up the initial stack so we can run C code. */
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movl $(init_thread_union+THREAD_SIZE),%esp
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- call init_pagetables
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-
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/* Jumps are relative: we're running __PAGE_OFFSET too low. */
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jmp lguest_init+__PAGE_OFFSET
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-/*
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- * Initialize page tables. This creates a PDE and a set of page
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- * tables, which are located immediately beyond __brk_base. The variable
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- * _brk_end is set up to point to the first "safe" location.
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- * Mappings are created both at virtual address 0 (identity mapping)
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- * and PAGE_OFFSET for up to _end.
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- *
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- * FIXME: This code is taken verbatim from arch/x86/kernel/head_32.S: they
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- * don't have a stack at this point, so we can't just use call and ret.
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- */
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-init_pagetables:
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-#if PTRS_PER_PMD > 1
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-#define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD)
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-#else
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-#define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD)
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-#endif
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-#define pa(X) ((X) - __PAGE_OFFSET)
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-
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-/* Enough space to fit pagetables for the low memory linear map */
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-MAPPING_BEYOND_END = \
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- PAGE_TABLE_SIZE(((1<<32) - __PAGE_OFFSET) >> PAGE_SHIFT) << PAGE_SHIFT
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-#ifdef CONFIG_X86_PAE
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-
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- /*
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- * In PAE mode initial_page_table is statically defined to contain
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- * enough entries to cover the VMSPLIT option (that is the top 1, 2 or 3
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- * entries). The identity mapping is handled by pointing two PGD entries
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- * to the first kernel PMD.
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- *
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- * Note the upper half of each PMD or PTE are always zero at this stage.
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- */
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-
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-#define KPMDS (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */
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-
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- xorl %ebx,%ebx /* %ebx is kept at zero */
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-
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- movl $pa(__brk_base), %edi
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- movl $pa(initial_pg_pmd), %edx
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- movl $PTE_IDENT_ATTR, %eax
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-10:
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- leal PDE_IDENT_ATTR(%edi),%ecx /* Create PMD entry */
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- movl %ecx,(%edx) /* Store PMD entry */
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- /* Upper half already zero */
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- addl $8,%edx
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- movl $512,%ecx
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-11:
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- stosl
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- xchgl %eax,%ebx
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- stosl
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- xchgl %eax,%ebx
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- addl $0x1000,%eax
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- loop 11b
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-
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- /*
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- * End condition: we must map up to the end + MAPPING_BEYOND_END.
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- */
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- movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp
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- cmpl %ebp,%eax
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- jb 10b
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-1:
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- addl $__PAGE_OFFSET, %edi
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- movl %edi, pa(_brk_end)
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- shrl $12, %eax
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- movl %eax, pa(max_pfn_mapped)
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-
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- /* Do early initialization of the fixmap area */
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- movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax
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- movl %eax,pa(initial_pg_pmd+0x1000*KPMDS-8)
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-#else /* Not PAE */
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-
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-page_pde_offset = (__PAGE_OFFSET >> 20);
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-
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- movl $pa(__brk_base), %edi
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- movl $pa(initial_page_table), %edx
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- movl $PTE_IDENT_ATTR, %eax
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-10:
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- leal PDE_IDENT_ATTR(%edi),%ecx /* Create PDE entry */
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- movl %ecx,(%edx) /* Store identity PDE entry */
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- movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */
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- addl $4,%edx
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- movl $1024, %ecx
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-11:
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- stosl
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- addl $0x1000,%eax
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- loop 11b
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- /*
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- * End condition: we must map up to the end + MAPPING_BEYOND_END.
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- */
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- movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp
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- cmpl %ebp,%eax
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- jb 10b
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- addl $__PAGE_OFFSET, %edi
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- movl %edi, pa(_brk_end)
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- shrl $12, %eax
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- movl %eax, pa(max_pfn_mapped)
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-
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- /* Do early initialization of the fixmap area */
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- movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax
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- movl %eax,pa(initial_page_table+0xffc)
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-#endif
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- ret
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-
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/*G:055
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* We create a macro which puts the assembler code between lgstart_ and lgend_
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* markers. These templates are put in the .text section: they can't be
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