xref: /kernel/linux/linux-6.6/arch/riscv/mm/pgtable.c (revision 62306a36) 
1// SPDX-License-Identifier: GPL-2.0
2
3#include <asm/pgalloc.h>
4#include <linux/gfp.h>
5#include <linux/kernel.h>
6#include <linux/pgtable.h>
7
8#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
9int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
10{
11	return 0;
12}
13
14void p4d_clear_huge(p4d_t *p4d)
15{
16}
17
18int pud_set_huge(pud_t *pud, phys_addr_t phys, pgprot_t prot)
19{
20	pud_t new_pud = pfn_pud(__phys_to_pfn(phys), prot);
21
22	set_pud(pud, new_pud);
23	return 1;
24}
25
26int pud_clear_huge(pud_t *pud)
27{
28	if (!pud_leaf(READ_ONCE(*pud)))
29		return 0;
30	pud_clear(pud);
31	return 1;
32}
33
34int pud_free_pmd_page(pud_t *pud, unsigned long addr)
35{
36	pmd_t *pmd = pud_pgtable(*pud);
37	int i;
38
39	pud_clear(pud);
40
41	flush_tlb_kernel_range(addr, addr + PUD_SIZE);
42
43	for (i = 0; i < PTRS_PER_PMD; i++) {
44		if (!pmd_none(pmd[i])) {
45			pte_t *pte = (pte_t *)pmd_page_vaddr(pmd[i]);
46
47			pte_free_kernel(NULL, pte);
48		}
49	}
50
51	pmd_free(NULL, pmd);
52
53	return 1;
54}
55
56int pmd_set_huge(pmd_t *pmd, phys_addr_t phys, pgprot_t prot)
57{
58	pmd_t new_pmd = pfn_pmd(__phys_to_pfn(phys), prot);
59
60	set_pmd(pmd, new_pmd);
61	return 1;
62}
63
64int pmd_clear_huge(pmd_t *pmd)
65{
66	if (!pmd_leaf(READ_ONCE(*pmd)))
67		return 0;
68	pmd_clear(pmd);
69	return 1;
70}
71
72int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
73{
74	pte_t *pte = (pte_t *)pmd_page_vaddr(*pmd);
75
76	pmd_clear(pmd);
77
78	flush_tlb_kernel_range(addr, addr + PMD_SIZE);
79	pte_free_kernel(NULL, pte);
80	return 1;
81}
82
83#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
84#ifdef CONFIG_TRANSPARENT_HUGEPAGE
85pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
86					unsigned long address, pmd_t *pmdp)
87{
88	pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp);
89
90	VM_BUG_ON(address & ~HPAGE_PMD_MASK);
91	VM_BUG_ON(pmd_trans_huge(*pmdp));
92	/*
93	 * When leaf PTE entries (regular pages) are collapsed into a leaf
94	 * PMD entry (huge page), a valid non-leaf PTE is converted into a
95	 * valid leaf PTE at the level 1 page table.  Since the sfence.vma
96	 * forms that specify an address only apply to leaf PTEs, we need a
97	 * global flush here.  collapse_huge_page() assumes these flushes are
98	 * eager, so just do the fence here.
99	 */
100	flush_tlb_mm(vma->vm_mm);
101	return pmd;
102}
103#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
104