Commit 1355c31e authored by Mike Rapoport's avatar Mike Rapoport Committed by Linus Torvalds
Browse files

asm-generic: pgalloc: provide generic pmd_alloc_one() and pmd_free_one() 



For most architectures that support >2 levels of page tables,
pmd_alloc_one() is a wrapper for __get_free_pages(), sometimes with
__GFP_ZERO and sometimes followed by memset(0) instead.

More elaborate versions on arm64 and x86 account memory for the user page
tables and call to pgtable_pmd_page_ctor() as the part of PMD page
initialization.

Move the arm64 version to include/asm-generic/pgalloc.h and use the
generic version on several architectures.

The pgtable_pmd_page_ctor() is a NOP when ARCH_ENABLE_SPLIT_PMD_PTLOCK is
not enabled, so there is no functional change for most architectures
except of the addition of __GFP_ACCOUNT for allocation of user page
tables.

The pmd_free() is a wrapper for free_page() in all the cases, so no
functional change here.

Signed-off-by: default avatarMike Rapoport <rppt@linux.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarPekka Enberg <penberg@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Link: http://lkml.kernel.org/r/20200627143453.31835-5-rppt@kernel.org


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 7278914c

arch/alpha/include/asm/pgalloc.h

+1 −14
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
#include <linux/mm.h>

#include <linux/mmzone.h>



#include <asm-generic/pgalloc.h>	/* for pte_{alloc,free}_one */

#include <asm-generic/pgalloc.h>



/*      

 * Allocate and free page tables. The xxx_kernel() versions are
@@ -40,17 +40,4 @@ pgd_free(struct mm_struct *mm, pgd_t *pgd) 
	free_page((unsigned long)pgd);

}



static inline pmd_t *

pmd_alloc_one(struct mm_struct *mm, unsigned long address)

{

	pmd_t *ret = (pmd_t *)__get_free_page(GFP_PGTABLE_USER);

	return ret;

}



static inline void

pmd_free(struct mm_struct *mm, pmd_t *pmd)

{

	free_page((unsigned long)pmd);

}



#endif /* _ALPHA_PGALLOC_H */

arch/arm/include/asm/pgalloc.h

+0 −11
Original line number Diff line number Diff line
@@ -22,17 +22,6 @@ 


#ifdef CONFIG_ARM_LPAE



static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)

{

	return (pmd_t *)get_zeroed_page(GFP_KERNEL);

}



static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)

{

	BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));

	free_page((unsigned long)pmd);

}



static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)

{

	set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE));

arch/arm64/include/asm/pgalloc.h

+1 −26
Original line number Diff line number Diff line
@@ -13,37 +13,12 @@ 
#include <asm/cacheflush.h>

#include <asm/tlbflush.h>



#include <asm-generic/pgalloc.h>	/* for pte_{alloc,free}_one */

#include <asm-generic/pgalloc.h>



#define PGD_SIZE	(PTRS_PER_PGD * sizeof(pgd_t))



#if CONFIG_PGTABLE_LEVELS > 2



static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)

{

	gfp_t gfp = GFP_PGTABLE_USER;

	struct page *page;



	if (mm == &init_mm)

		gfp = GFP_PGTABLE_KERNEL;



	page = alloc_page(gfp);

	if (!page)

		return NULL;

	if (!pgtable_pmd_page_ctor(page)) {

		__free_page(page);

		return NULL;

	}

	return page_address(page);

}



static inline void pmd_free(struct mm_struct *mm, pmd_t *pmdp)

{

	BUG_ON((unsigned long)pmdp & (PAGE_SIZE-1));

	pgtable_pmd_page_dtor(virt_to_page(pmdp));

	free_page((unsigned long)pmdp);

}



static inline void __pud_populate(pud_t *pudp, phys_addr_t pmdp, pudval_t prot)

{

	set_pud(pudp, __pud(__phys_to_pud_val(pmdp) | prot));

arch/ia64/include/asm/pgalloc.h

+0 −10
Original line number Diff line number Diff line
@@ -59,16 +59,6 @@ pud_populate(struct mm_struct *mm, pud_t * pud_entry, pmd_t * pmd) 
	pud_val(*pud_entry) = __pa(pmd);

}



static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)

{

	return (pmd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);

}



static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)

{

	free_page((unsigned long)pmd);

}



#define __pmd_free_tlb(tlb, pmd, address)	pmd_free((tlb)->mm, pmd)



static inline void

arch/mips/include/asm/pgalloc.h

+2 −6
Original line number Diff line number Diff line
@@ -13,7 +13,8 @@ 
#include <linux/mm.h>

#include <linux/sched.h>



#include <asm-generic/pgalloc.h>	/* for pte_{alloc,free}_one */

#define __HAVE_ARCH_PMD_ALLOC_ONE

#include <asm-generic/pgalloc.h>



static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,

	pte_t *pte)
@@ -70,11 +71,6 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address) 
	return pmd;

}



static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)

{

	free_pages((unsigned long)pmd, PMD_ORDER);

}



#define __pmd_free_tlb(tlb, x, addr)	pmd_free((tlb)->mm, x)



#endif

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