Commit 59b3d020 authored by Thomas Garnier's avatar Thomas Garnier Committed by Ingo Molnar
Browse files

x86/mm: Update physical mapping variable names 



Change the variable names in kernel_physical_mapping_init() and related
functions to correctly reflect physical and virtual memory addresses.
Also add comments on each function to describe usage and alignment
constraints.

Signed-off-by: default avatarThomas Garnier <thgarnie@google.com>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1466556426-32664-3-git-send-email-keescook@chromium.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent d899a7d1

arch/x86/mm/init_64.c

+96 −66
Original line number Diff line number Diff line
@@ -328,22 +328,30 @@ void __init cleanup_highmap(void) 
	}

}



/*

 * Create PTE level page table mapping for physical addresses.

 * It returns the last physical address mapped.

 */

static unsigned long __meminit

phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,

phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,

	      pgprot_t prot)

{

	unsigned long pages = 0, next;

	unsigned long last_map_addr = end;

	unsigned long pages = 0, paddr_next;

	unsigned long paddr_last = paddr_end;

	pte_t *pte;

	int i;



	pte_t *pte = pte_page + pte_index(addr);

	pte = pte_page + pte_index(paddr);

	i = pte_index(paddr);



	for (i = pte_index(addr); i < PTRS_PER_PTE; i++, addr = next, pte++) {

		next = (addr & PAGE_MASK) + PAGE_SIZE;

		if (addr >= end) {

	for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {

		paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;

		if (paddr >= paddr_end) {

			if (!after_bootmem &&

			    !e820_any_mapped(addr & PAGE_MASK, next, E820_RAM) &&

			    !e820_any_mapped(addr & PAGE_MASK, next, E820_RESERVED_KERN))

			    !e820_any_mapped(paddr & PAGE_MASK, paddr_next,

					     E820_RAM) &&

			    !e820_any_mapped(paddr & PAGE_MASK, paddr_next,

					     E820_RESERVED_KERN))

				set_pte(pte, __pte(0));

			continue;

		}
@@ -361,37 +369,44 @@ phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end, 
		}



		if (0)

			printk("   pte=%p addr=%lx pte=%016lx\n",

			       pte, addr, pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL).pte);

			pr_info("   pte=%p addr=%lx pte=%016lx\n", pte, paddr,

				pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);

		pages++;

		set_pte(pte, pfn_pte(addr >> PAGE_SHIFT, prot));

		last_map_addr = (addr & PAGE_MASK) + PAGE_SIZE;

		set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));

		paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;

	}



	update_page_count(PG_LEVEL_4K, pages);



	return last_map_addr;

	return paddr_last;

}



/*

 * Create PMD level page table mapping for physical addresses. The virtual

 * and physical address have to be aligned at this level.

 * It returns the last physical address mapped.

 */

static unsigned long __meminit

phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,

phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,

	      unsigned long page_size_mask, pgprot_t prot)

{

	unsigned long pages = 0, next;

	unsigned long last_map_addr = end;

	unsigned long pages = 0, paddr_next;

	unsigned long paddr_last = paddr_end;



	int i = pmd_index(address);

	int i = pmd_index(paddr);



	for (; i < PTRS_PER_PMD; i++, address = next) {

		pmd_t *pmd = pmd_page + pmd_index(address);

	for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {

		pmd_t *pmd = pmd_page + pmd_index(paddr);

		pte_t *pte;

		pgprot_t new_prot = prot;



		next = (address & PMD_MASK) + PMD_SIZE;

		if (address >= end) {

		paddr_next = (paddr & PMD_MASK) + PMD_SIZE;

		if (paddr >= paddr_end) {

			if (!after_bootmem &&

			    !e820_any_mapped(address & PMD_MASK, next, E820_RAM) &&

			    !e820_any_mapped(address & PMD_MASK, next, E820_RESERVED_KERN))

			    !e820_any_mapped(paddr & PMD_MASK, paddr_next,

					     E820_RAM) &&

			    !e820_any_mapped(paddr & PMD_MASK, paddr_next,

					     E820_RESERVED_KERN))

				set_pmd(pmd, __pmd(0));

			continue;

		}
@@ -400,8 +415,8 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, 
			if (!pmd_large(*pmd)) {

				spin_lock(&init_mm.page_table_lock);

				pte = (pte_t *)pmd_page_vaddr(*pmd);

				last_map_addr = phys_pte_init(pte, address,

								end, prot);

				paddr_last = phys_pte_init(pte, paddr,

							   paddr_end, prot);

				spin_unlock(&init_mm.page_table_lock);

				continue;

			}
@@ -420,7 +435,7 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, 
			if (page_size_mask & (1 << PG_LEVEL_2M)) {

				if (!after_bootmem)

					pages++;

				last_map_addr = next;

				paddr_last = paddr_next;

				continue;

			}

			new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
@@ -430,42 +445,49 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end, 
			pages++;

			spin_lock(&init_mm.page_table_lock);

			set_pte((pte_t *)pmd,

				pfn_pte((address & PMD_MASK) >> PAGE_SHIFT,

				pfn_pte((paddr & PMD_MASK) >> PAGE_SHIFT,

					__pgprot(pgprot_val(prot) | _PAGE_PSE)));

			spin_unlock(&init_mm.page_table_lock);

			last_map_addr = next;

			paddr_last = paddr_next;

			continue;

		}



		pte = alloc_low_page();

		last_map_addr = phys_pte_init(pte, address, end, new_prot);

		paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot);



		spin_lock(&init_mm.page_table_lock);

		pmd_populate_kernel(&init_mm, pmd, pte);

		spin_unlock(&init_mm.page_table_lock);

	}

	update_page_count(PG_LEVEL_2M, pages);

	return last_map_addr;

	return paddr_last;

}



/*

 * Create PUD level page table mapping for physical addresses. The virtual

 * and physical address have to be aligned at this level.

 * It returns the last physical address mapped.

 */

static unsigned long __meminit

phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,

phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,

	      unsigned long page_size_mask)

{

	unsigned long pages = 0, next;

	unsigned long last_map_addr = end;

	int i = pud_index(addr);

	unsigned long pages = 0, paddr_next;

	unsigned long paddr_last = paddr_end;

	int i = pud_index(paddr);



	for (; i < PTRS_PER_PUD; i++, addr = next) {

		pud_t *pud = pud_page + pud_index(addr);

	for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {

		pud_t *pud = pud_page + pud_index(paddr);

		pmd_t *pmd;

		pgprot_t prot = PAGE_KERNEL;



		next = (addr & PUD_MASK) + PUD_SIZE;

		if (addr >= end) {

		paddr_next = (paddr & PUD_MASK) + PUD_SIZE;

		if (paddr >= paddr_end) {

			if (!after_bootmem &&

			    !e820_any_mapped(addr & PUD_MASK, next, E820_RAM) &&

			    !e820_any_mapped(addr & PUD_MASK, next, E820_RESERVED_KERN))

			    !e820_any_mapped(paddr & PUD_MASK, paddr_next,

					     E820_RAM) &&

			    !e820_any_mapped(paddr & PUD_MASK, paddr_next,

					     E820_RESERVED_KERN))

				set_pud(pud, __pud(0));

			continue;

		}
@@ -473,8 +495,10 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, 
		if (pud_val(*pud)) {

			if (!pud_large(*pud)) {

				pmd = pmd_offset(pud, 0);

				last_map_addr = phys_pmd_init(pmd, addr, end,

							 page_size_mask, prot);

				paddr_last = phys_pmd_init(pmd, paddr,

							   paddr_end,

							   page_size_mask,

							   prot);

				__flush_tlb_all();

				continue;

			}
@@ -493,7 +517,7 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, 
			if (page_size_mask & (1 << PG_LEVEL_1G)) {

				if (!after_bootmem)

					pages++;

				last_map_addr = next;

				paddr_last = paddr_next;

				continue;

			}

			prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
@@ -503,16 +527,16 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, 
			pages++;

			spin_lock(&init_mm.page_table_lock);

			set_pte((pte_t *)pud,

				pfn_pte((addr & PUD_MASK) >> PAGE_SHIFT,

				pfn_pte((paddr & PUD_MASK) >> PAGE_SHIFT,

					PAGE_KERNEL_LARGE));

			spin_unlock(&init_mm.page_table_lock);

			last_map_addr = next;

			paddr_last = paddr_next;

			continue;

		}



		pmd = alloc_low_page();

		last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,

					      prot);

		paddr_last = phys_pmd_init(pmd, paddr, paddr_end,

					   page_size_mask, prot);



		spin_lock(&init_mm.page_table_lock);

		pud_populate(&init_mm, pud, pmd);
@@ -522,37 +546,43 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end, 


	update_page_count(PG_LEVEL_1G, pages);



	return last_map_addr;

	return paddr_last;

}



/*

 * Create page table mapping for the physical memory for specific physical

 * addresses. The virtual and physical addresses have to be aligned on PUD level

 * down. It returns the last physical address mapped.

 */

unsigned long __meminit

kernel_physical_mapping_init(unsigned long start,

			     unsigned long end,

kernel_physical_mapping_init(unsigned long paddr_start,

			     unsigned long paddr_end,

			     unsigned long page_size_mask)

{

	bool pgd_changed = false;

	unsigned long next, last_map_addr = end;

	unsigned long addr;

	unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;



	start = (unsigned long)__va(start);

	end = (unsigned long)__va(end);

	addr = start;

	paddr_last = paddr_end;

	vaddr = (unsigned long)__va(paddr_start);

	vaddr_end = (unsigned long)__va(paddr_end);

	vaddr_start = vaddr;



	for (; start < end; start = next) {

		pgd_t *pgd = pgd_offset_k(start);

	for (; vaddr < vaddr_end; vaddr = vaddr_next) {

		pgd_t *pgd = pgd_offset_k(vaddr);

		pud_t *pud;



		next = (start & PGDIR_MASK) + PGDIR_SIZE;

		vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;



		if (pgd_val(*pgd)) {

			pud = (pud_t *)pgd_page_vaddr(*pgd);

			last_map_addr = phys_pud_init(pud, __pa(start),

						 __pa(end), page_size_mask);

			paddr_last = phys_pud_init(pud, __pa(vaddr),

						   __pa(vaddr_end),

						   page_size_mask);

			continue;

		}



		pud = alloc_low_page();

		last_map_addr = phys_pud_init(pud, __pa(start), __pa(end),

		paddr_last = phys_pud_init(pud, __pa(vaddr), __pa(vaddr_end),

					   page_size_mask);



		spin_lock(&init_mm.page_table_lock);
@@ -562,11 +592,11 @@ kernel_physical_mapping_init(unsigned long start, 
	}



	if (pgd_changed)

		sync_global_pgds(addr, end - 1, 0);

		sync_global_pgds(vaddr_start, vaddr_end - 1, 0);



	__flush_tlb_all();



	return last_map_addr;

	return paddr_last;

}



#ifndef CONFIG_NUMA

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