Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  *  linux/arch/arm/mm/pgd.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  *  Copyright (C) 1998-2005 Russell King
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) #include <linux/mm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/gfp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/highmem.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <asm/cp15.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <asm/pgalloc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <asm/page.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <asm/tlbflush.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include "mm.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #ifdef CONFIG_ARM_LPAE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #define __pgd_alloc()	kmalloc_array(PTRS_PER_PGD, sizeof(pgd_t), GFP_KERNEL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #define __pgd_free(pgd)	kfree(pgd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #define __pgd_alloc()	(pgd_t *)__get_free_pages(GFP_KERNEL, 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #define __pgd_free(pgd)	free_pages((unsigned long)pgd, 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28)  * need to get a 16k page for level 1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) pgd_t *pgd_alloc(struct mm_struct *mm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	pgd_t *new_pgd, *init_pgd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	p4d_t *new_p4d, *init_p4d;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	pud_t *new_pud, *init_pud;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	pmd_t *new_pmd, *init_pmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	pte_t *new_pte, *init_pte;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	new_pgd = __pgd_alloc();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	if (!new_pgd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 		goto no_pgd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	memset(new_pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	 * Copy over the kernel and IO PGD entries
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	init_pgd = pgd_offset_k(0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	memcpy(new_pgd + USER_PTRS_PER_PGD, init_pgd + USER_PTRS_PER_PGD,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) #ifdef CONFIG_ARM_LPAE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	 * Allocate PMD table for modules and pkmap mappings.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	new_p4d = p4d_alloc(mm, new_pgd + pgd_index(MODULES_VADDR),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 			    MODULES_VADDR);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	if (!new_p4d)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 		goto no_p4d;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	new_pud = pud_alloc(mm, new_p4d, MODULES_VADDR);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	if (!new_pud)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 		goto no_pud;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	new_pmd = pmd_alloc(mm, new_pud, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	if (!new_pmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		goto no_pmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	if (!vectors_high()) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 		/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 		 * On ARM, first page must always be allocated since it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 		 * contains the machine vectors. The vectors are always high
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		 * with LPAE.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 		 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 		new_p4d = p4d_alloc(mm, new_pgd, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		if (!new_p4d)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 			goto no_p4d;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 		new_pud = pud_alloc(mm, new_p4d, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 		if (!new_pud)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 			goto no_pud;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 		new_pmd = pmd_alloc(mm, new_pud, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 		if (!new_pmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 			goto no_pmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 		new_pte = pte_alloc_map(mm, new_pmd, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 		if (!new_pte)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 			goto no_pte;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) #ifndef CONFIG_ARM_LPAE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 		/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 		 * Modify the PTE pointer to have the correct domain.  This
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 		 * needs to be the vectors domain to avoid the low vectors
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 		 * being unmapped.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 		 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 		pmd_val(*new_pmd) &= ~PMD_DOMAIN_MASK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		pmd_val(*new_pmd) |= PMD_DOMAIN(DOMAIN_VECTORS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 		init_p4d = p4d_offset(init_pgd, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 		init_pud = pud_offset(init_p4d, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 		init_pmd = pmd_offset(init_pud, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 		init_pte = pte_offset_map(init_pmd, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 		set_pte_ext(new_pte + 0, init_pte[0], 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 		set_pte_ext(new_pte + 1, init_pte[1], 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		pte_unmap(init_pte);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 		pte_unmap(new_pte);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	return new_pgd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) no_pte:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	pmd_free(mm, new_pmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	mm_dec_nr_pmds(mm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) no_pmd:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	pud_free(mm, new_pud);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) no_pud:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	p4d_free(mm, new_p4d);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) no_p4d:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	__pgd_free(new_pgd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) no_pgd:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 	pgd_t *pgd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	p4d_t *p4d;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	pud_t *pud;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	pmd_t *pmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	pgtable_t pte;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	if (!pgd_base)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	pgd = pgd_base + pgd_index(0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	if (pgd_none_or_clear_bad(pgd))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 		goto no_pgd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	p4d = p4d_offset(pgd, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	if (p4d_none_or_clear_bad(p4d))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 		goto no_p4d;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	pud = pud_offset(p4d, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	if (pud_none_or_clear_bad(pud))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 		goto no_pud;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	pmd = pmd_offset(pud, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	if (pmd_none_or_clear_bad(pmd))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 		goto no_pmd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	pte = pmd_pgtable(*pmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	pmd_clear(pmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	pte_free(mm, pte);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	mm_dec_nr_ptes(mm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) no_pmd:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	pud_clear(pud);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	pmd_free(mm, pmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	mm_dec_nr_pmds(mm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) no_pud:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	p4d_clear(p4d);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	pud_free(mm, pud);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) no_p4d:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	pgd_clear(pgd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	p4d_free(mm, p4d);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) no_pgd:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) #ifdef CONFIG_ARM_LPAE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	 * Free modules/pkmap or identity pmd tables.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 	for (pgd = pgd_base; pgd < pgd_base + PTRS_PER_PGD; pgd++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		if (pgd_none_or_clear_bad(pgd))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 		if (pgd_val(*pgd) & L_PGD_SWAPPER)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 		p4d = p4d_offset(pgd, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 		if (p4d_none_or_clear_bad(p4d))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 		pud = pud_offset(p4d, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 		if (pud_none_or_clear_bad(pud))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 		pmd = pmd_offset(pud, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 		pud_clear(pud);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 		pmd_free(mm, pmd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 		mm_dec_nr_pmds(mm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		p4d_clear(p4d);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 		pud_free(mm, pud);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 		mm_dec_nr_puds(mm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 		pgd_clear(pgd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 		p4d_free(mm, p4d);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 	__pgd_free(pgd_base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) }