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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>
100 lines
2.3 KiB
C
100 lines
2.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/memblock.h>
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#include <linux/mmdebug.h>
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#include <linux/export.h>
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#include <linux/mm.h>
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#include <asm/page.h>
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#include <linux/vmalloc.h>
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#include "physaddr.h"
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#ifdef CONFIG_X86_64
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#ifdef CONFIG_DEBUG_VIRTUAL
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unsigned long __phys_addr(unsigned long x)
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{
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unsigned long y = x - __START_KERNEL_map;
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/* use the carry flag to determine if x was < __START_KERNEL_map */
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if (unlikely(x > y)) {
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x = y + phys_base;
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VIRTUAL_BUG_ON(y >= KERNEL_IMAGE_SIZE);
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} else {
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x = y + (__START_KERNEL_map - PAGE_OFFSET);
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/* carry flag will be set if starting x was >= PAGE_OFFSET */
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VIRTUAL_BUG_ON((x > y) || !phys_addr_valid(x));
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}
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return x;
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}
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EXPORT_SYMBOL(__phys_addr);
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unsigned long __phys_addr_symbol(unsigned long x)
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{
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unsigned long y = x - __START_KERNEL_map;
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/* only check upper bounds since lower bounds will trigger carry */
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VIRTUAL_BUG_ON(y >= KERNEL_IMAGE_SIZE);
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return y + phys_base;
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}
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EXPORT_SYMBOL(__phys_addr_symbol);
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#endif
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bool __virt_addr_valid(unsigned long x)
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{
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unsigned long y = x - __START_KERNEL_map;
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/* use the carry flag to determine if x was < __START_KERNEL_map */
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if (unlikely(x > y)) {
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x = y + phys_base;
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if (y >= KERNEL_IMAGE_SIZE)
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return false;
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} else {
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x = y + (__START_KERNEL_map - PAGE_OFFSET);
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/* carry flag will be set if starting x was >= PAGE_OFFSET */
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if ((x > y) || !phys_addr_valid(x))
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return false;
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}
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return pfn_valid(x >> PAGE_SHIFT);
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}
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EXPORT_SYMBOL(__virt_addr_valid);
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#else
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#ifdef CONFIG_DEBUG_VIRTUAL
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unsigned long __phys_addr(unsigned long x)
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{
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unsigned long phys_addr = x - PAGE_OFFSET;
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/* VMALLOC_* aren't constants */
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VIRTUAL_BUG_ON(x < PAGE_OFFSET);
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VIRTUAL_BUG_ON(__vmalloc_start_set && is_vmalloc_addr((void *) x));
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/* max_low_pfn is set early, but not _that_ early */
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if (max_low_pfn) {
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VIRTUAL_BUG_ON((phys_addr >> PAGE_SHIFT) > max_low_pfn);
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BUG_ON(slow_virt_to_phys((void *)x) != phys_addr);
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}
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return phys_addr;
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}
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EXPORT_SYMBOL(__phys_addr);
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#endif
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bool __virt_addr_valid(unsigned long x)
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{
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if (x < PAGE_OFFSET)
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return false;
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if (__vmalloc_start_set && is_vmalloc_addr((void *) x))
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return false;
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if (x >= FIXADDR_START)
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return false;
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return pfn_valid((x - PAGE_OFFSET) >> PAGE_SHIFT);
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}
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EXPORT_SYMBOL(__virt_addr_valid);
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#endif /* CONFIG_X86_64 */
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