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a9b3c355c2
We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free(). Let's finish the work and add a generic PGD-level
alloc helper as well.
Unlike at lower levels, almost all architectures need some specific magic
at PGD level (typically initialising PGD entries), so introducing a
generic pgd_alloc() isn't worth it. Instead we introduce two new helpers,
__pgd_alloc() and __pgd_free(), and make use of them in the arch-specific
pgd_alloc() and pgd_free() wherever possible. To accommodate as many arch
as possible, __pgd_alloc() takes a page allocation order.
Because pagetable_alloc() allocates zeroed pages, explicit zeroing in
pgd_alloc() becomes redundant and we can get rid of it. Some trivial
implementations of pgd_free() also become unnecessary once __pgd_alloc()
is used; remove them.
Another small improvement is consistent accounting of PGD pages by using
GFP_PGTABLE_{USER,KERNEL} as appropriate.
Not all PGD allocations can be handled by the generic helpers. In
particular, multiple architectures allocate PGDs from a kmem_cache, and
those PGDs may not be page-sized.
Link: https://lkml.kernel.org/r/20250103184415.2744423-6-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
75 lines
1.6 KiB
C
75 lines
1.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __ASM_CSKY_PGALLOC_H
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#define __ASM_CSKY_PGALLOC_H
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#include <linux/highmem.h>
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#include <linux/mm.h>
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#include <linux/sched.h>
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#define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
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#include <asm-generic/pgalloc.h>
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static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
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pte_t *pte)
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{
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set_pmd(pmd, __pmd(__pa(pte)));
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}
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static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
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pgtable_t pte)
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{
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set_pmd(pmd, __pmd(__pa(page_address(pte))));
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}
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extern void pgd_init(unsigned long *p);
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static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
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{
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pte_t *pte;
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unsigned long i;
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pte = (pte_t *) __get_free_page(GFP_KERNEL);
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if (!pte)
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return NULL;
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for (i = 0; i < PAGE_SIZE/sizeof(pte_t); i++)
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(pte + i)->pte_low = _PAGE_GLOBAL;
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return pte;
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}
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static inline pgd_t *pgd_alloc(struct mm_struct *mm)
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{
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pgd_t *ret;
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pgd_t *init;
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ret = __pgd_alloc(mm, 0);
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if (ret) {
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init = pgd_offset(&init_mm, 0UL);
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pgd_init((unsigned long *)ret);
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memcpy(ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
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(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
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/* prevent out of order excute */
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smp_mb();
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#ifdef CONFIG_CPU_NEED_TLBSYNC
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dcache_wb_range((unsigned int)ret,
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(unsigned int)(ret + PTRS_PER_PGD));
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#endif
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}
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return ret;
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}
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#define __pte_free_tlb(tlb, pte, address) \
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do { \
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pagetable_dtor(page_ptdesc(pte)); \
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tlb_remove_page_ptdesc(tlb, page_ptdesc(pte)); \
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} while (0)
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extern void pagetable_init(void);
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extern void mmu_init(unsigned long min_pfn, unsigned long max_pfn);
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extern void pre_trap_init(void);
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#endif /* __ASM_CSKY_PGALLOC_H */
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