linux-loongson/arch/hexagon/include/asm/pgalloc.h
Qi Zheng e3ecf7c7d0 mm: pgtable: convert some architectures to use tlb_remove_ptdesc()
Now, the nine architectures of csky, hexagon, loongarch, m68k, mips,
nios2, openrisc, sh and um do not select CONFIG_MMU_GATHER_RCU_TABLE_FREE,
and just call pagetable_dtor() + tlb_remove_page_ptdesc() (the wrapper of
tlb_remove_page()).  This is the same as the implementation of
tlb_remove_{ptdesc|table}() under !CONFIG_MMU_GATHER_TABLE_FREE, so
convert these architectures to use tlb_remove_ptdesc().

The ultimate goal is to make the architecture only use tlb_remove_ptdesc()
or tlb_remove_table() for page table pages.

[zhengqi.arch@bytedance.com: v2]
  Link: https://lkml.kernel.org/r/20250303072603.45423-1-zhengqi.arch@bytedance.com
[akpm@linux-foundation.org: remove trailing semi in arch/loongarch/include/asm/pgalloc.h]
Link: https://lkml.kernel.org/r/19db3e8673b67bad2f1df1ab37f1c89d99eacfea.1740454179.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickens <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Matthew Wilcow (Oracle) <willy@infradead.org>
Cc: "Mike Rapoport (IBM)" <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-04-01 15:17:13 -07:00

94 lines
2.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Page table support for the Hexagon architecture
*
* Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
*/
#ifndef _ASM_PGALLOC_H
#define _ASM_PGALLOC_H
#include <asm/mem-layout.h>
#include <asm/atomic.h>
#include <asm-generic/pgalloc.h>
extern unsigned long long kmap_generation;
/*
* Page table creation interface
*/
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd;
pgd = __pgd_alloc(mm, 0);
/*
* There may be better ways to do this, but to ensure
* that new address spaces always contain the kernel
* base mapping, and to ensure that the user area is
* initially marked invalid, initialize the new map
* map with a copy of the kernel's persistent map.
*/
memcpy(pgd, swapper_pg_dir, PTRS_PER_PGD*sizeof(pgd_t));
mm->context.generation = kmap_generation;
/* Physical version is what is passed to virtual machine on switch */
mm->context.ptbase = __pa(pgd);
return pgd;
}
static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
pgtable_t pte)
{
/*
* Conveniently, zero in 3 LSB means indirect 4K page table.
* Not so convenient when you're trying to vary the page size.
*/
set_pmd(pmd, __pmd(((unsigned long)page_to_pfn(pte) << PAGE_SHIFT) |
HEXAGON_L1_PTE_SIZE));
}
/*
* Other architectures seem to have ways of making all processes
* share the same pmd's for their kernel mappings, but the v0.3
* Hexagon VM spec has a "monolithic" L1 table for user and kernel
* segments. We track "generations" of the kernel map to minimize
* overhead, and update the "slave" copies of the kernel mappings
* as part of switch_mm. However, we still need to update the
* kernel map of the active thread who's calling pmd_populate_kernel...
*/
static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
pte_t *pte)
{
extern spinlock_t kmap_gen_lock;
pmd_t *ppmd;
int pmdindex;
spin_lock(&kmap_gen_lock);
kmap_generation++;
mm->context.generation = kmap_generation;
current->active_mm->context.generation = kmap_generation;
spin_unlock(&kmap_gen_lock);
set_pmd(pmd, __pmd(((unsigned long)__pa(pte)) | HEXAGON_L1_PTE_SIZE));
/*
* Now the "slave" copy of the current thread.
* This is pointer arithmetic, not byte addresses!
*/
pmdindex = (pgd_t *)pmd - mm->pgd;
ppmd = (pmd_t *)current->active_mm->pgd + pmdindex;
set_pmd(ppmd, __pmd(((unsigned long)__pa(pte)) | HEXAGON_L1_PTE_SIZE));
if (pmdindex > max_kernel_seg)
max_kernel_seg = pmdindex;
}
#define __pte_free_tlb(tlb, pte, addr) \
tlb_remove_ptdesc((tlb), page_ptdesc(pte))
#endif