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186525bd6b
- Untangle the somewhat incestous way of how VMALLOC_START is used all across the
kernel, but is, on x86, defined deep inside one of the lowest level page table headers.
It doesn't help that vmalloc.h only includes a single asm header:
#include <asm/page.h> /* pgprot_t */
So there was no existing cross-arch way to decouple address layout
definitions from page.h details. I used this:
#ifndef VMALLOC_START
# include <asm/vmalloc.h>
#endif
This way every architecture that wants to simplify page.h can do so.
- Also on x86 we had a couple of LDT related inline functions that used
the late-stage address space layout positions - but these could be
uninlined without real trouble - the end result is cleaner this way as
well.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
107 lines
2.3 KiB
C
107 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/mm.h>
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#include <linux/nmi.h>
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#include <linux/swap.h>
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#include <linux/smp.h>
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#include <linux/highmem.h>
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#include <linux/pagemap.h>
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#include <linux/spinlock.h>
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#include <asm/cpu_entry_area.h>
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#include <asm/pgtable.h>
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#include <asm/pgalloc.h>
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#include <asm/fixmap.h>
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#include <asm/e820/api.h>
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#include <asm/tlb.h>
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#include <asm/tlbflush.h>
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#include <asm/io.h>
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#include <linux/vmalloc.h>
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unsigned int __VMALLOC_RESERVE = 128 << 20;
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/*
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* Associate a virtual page frame with a given physical page frame
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* and protection flags for that frame.
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*/
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void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
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{
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pgd_t *pgd;
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p4d_t *p4d;
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pud_t *pud;
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pmd_t *pmd;
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pte_t *pte;
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pgd = swapper_pg_dir + pgd_index(vaddr);
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if (pgd_none(*pgd)) {
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BUG();
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return;
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}
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p4d = p4d_offset(pgd, vaddr);
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if (p4d_none(*p4d)) {
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BUG();
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return;
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}
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pud = pud_offset(p4d, vaddr);
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if (pud_none(*pud)) {
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BUG();
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return;
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}
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pmd = pmd_offset(pud, vaddr);
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if (pmd_none(*pmd)) {
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BUG();
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return;
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}
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pte = pte_offset_kernel(pmd, vaddr);
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if (!pte_none(pteval))
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set_pte_at(&init_mm, vaddr, pte, pteval);
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else
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pte_clear(&init_mm, vaddr, pte);
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/*
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* It's enough to flush this one mapping.
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* (PGE mappings get flushed as well)
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*/
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__flush_tlb_one_kernel(vaddr);
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}
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unsigned long __FIXADDR_TOP = 0xfffff000;
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EXPORT_SYMBOL(__FIXADDR_TOP);
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/*
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* vmalloc=size forces the vmalloc area to be exactly 'size'
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* bytes. This can be used to increase (or decrease) the
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* vmalloc area - the default is 128m.
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*/
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static int __init parse_vmalloc(char *arg)
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{
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if (!arg)
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return -EINVAL;
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/* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/
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__VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET;
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return 0;
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}
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early_param("vmalloc", parse_vmalloc);
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/*
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* reservetop=size reserves a hole at the top of the kernel address space which
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* a hypervisor can load into later. Needed for dynamically loaded hypervisors,
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* so relocating the fixmap can be done before paging initialization.
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*/
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static int __init parse_reservetop(char *arg)
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{
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unsigned long address;
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if (!arg)
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return -EINVAL;
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address = memparse(arg, &arg);
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reserve_top_address(address);
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early_ioremap_init();
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return 0;
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}
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early_param("reservetop", parse_reservetop);
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