From 84e6ffb2c49c7901a9efb54b497d2eb84c3bef8c Mon Sep 17 00:00:00 2001 From: Mike Rapoport Date: Thu, 4 Jun 2020 16:46:19 -0700 Subject: arm: add support for folded p4d page tables Implement primitives necessary for the 4th level folding, add walks of p4d level where appropriate, and remove __ARCH_USE_5LEVEL_HACK. [rppt@linux.ibm.com: fix kexec] Link: http://lkml.kernel.org/r/20200508174232.GA759899@linux.ibm.com Signed-off-by: Mike Rapoport Signed-off-by: Andrew Morton Tested-by: Marek Szyprowski Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Brian Cain Cc: Catalin Marinas Cc: Christophe Leroy Cc: Fenghua Yu Cc: Geert Uytterhoeven Cc: Guan Xuetao Cc: James Morse Cc: Jonas Bonn Cc: Julien Thierry Cc: Ley Foon Tan Cc: Marc Zyngier Cc: Michael Ellerman Cc: Paul Mackerras Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Stefan Kristiansson Cc: Suzuki K Poulose Cc: Tony Luck Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200414153455.21744-3-rppt@kernel.org Signed-off-by: Linus Torvalds --- arch/arm/mm/pgd.c | 40 +++++++++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 7 deletions(-) (limited to 'arch/arm/mm/pgd.c') diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c index 478bd2c6aa50..c5e1b27046a8 100644 --- a/arch/arm/mm/pgd.c +++ b/arch/arm/mm/pgd.c @@ -30,6 +30,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm) { pgd_t *new_pgd, *init_pgd; + p4d_t *new_p4d, *init_p4d; pud_t *new_pud, *init_pud; pmd_t *new_pmd, *init_pmd; pte_t *new_pte, *init_pte; @@ -53,8 +54,12 @@ pgd_t *pgd_alloc(struct mm_struct *mm) /* * Allocate PMD table for modules and pkmap mappings. */ - new_pud = pud_alloc(mm, new_pgd + pgd_index(MODULES_VADDR), + new_p4d = p4d_alloc(mm, new_pgd + pgd_index(MODULES_VADDR), MODULES_VADDR); + if (!new_p4d) + goto no_p4d; + + new_pud = pud_alloc(mm, new_p4d, MODULES_VADDR); if (!new_pud) goto no_pud; @@ -69,7 +74,11 @@ pgd_t *pgd_alloc(struct mm_struct *mm) * contains the machine vectors. The vectors are always high * with LPAE. */ - new_pud = pud_alloc(mm, new_pgd, 0); + new_p4d = p4d_alloc(mm, new_pgd, 0); + if (!new_p4d) + goto no_p4d; + + new_pud = pud_alloc(mm, new_p4d, 0); if (!new_pud) goto no_pud; @@ -91,7 +100,8 @@ pgd_t *pgd_alloc(struct mm_struct *mm) pmd_val(*new_pmd) |= PMD_DOMAIN(DOMAIN_VECTORS); #endif - init_pud = pud_offset(init_pgd, 0); + init_p4d = p4d_offset(init_pgd, 0); + init_pud = pud_offset(init_p4d, 0); init_pmd = pmd_offset(init_pud, 0); init_pte = pte_offset_map(init_pmd, 0); set_pte_ext(new_pte + 0, init_pte[0], 0); @@ -108,6 +118,8 @@ no_pte: no_pmd: pud_free(mm, new_pud); no_pud: + p4d_free(mm, new_p4d); +no_p4d: __pgd_free(new_pgd); no_pgd: return NULL; @@ -116,6 +128,7 @@ no_pgd: void pgd_free(struct mm_struct *mm, pgd_t *pgd_base) { pgd_t *pgd; + p4d_t *p4d; pud_t *pud; pmd_t *pmd; pgtable_t pte; @@ -127,7 +140,11 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd_base) if (pgd_none_or_clear_bad(pgd)) goto no_pgd; - pud = pud_offset(pgd, 0); + p4d = p4d_offset(pgd, 0); + if (p4d_none_or_clear_bad(p4d)) + goto no_p4d; + + pud = pud_offset(p4d, 0); if (pud_none_or_clear_bad(pud)) goto no_pud; @@ -144,8 +161,11 @@ no_pmd: pmd_free(mm, pmd); mm_dec_nr_pmds(mm); no_pud: - pgd_clear(pgd); + p4d_clear(p4d); pud_free(mm, pud); +no_p4d: + pgd_clear(pgd); + p4d_free(mm, p4d); no_pgd: #ifdef CONFIG_ARM_LPAE /* @@ -156,15 +176,21 @@ no_pgd: continue; if (pgd_val(*pgd) & L_PGD_SWAPPER) continue; - pud = pud_offset(pgd, 0); + p4d = p4d_offset(pgd, 0); + if (p4d_none_or_clear_bad(p4d)) + continue; + pud = pud_offset(p4d, 0); if (pud_none_or_clear_bad(pud)) continue; pmd = pmd_offset(pud, 0); pud_clear(pud); pmd_free(mm, pmd); mm_dec_nr_pmds(mm); - pgd_clear(pgd); + p4d_clear(p4d); pud_free(mm, pud); + mm_dec_nr_puds(mm); + pgd_clear(pgd); + p4d_free(mm, p4d); } #endif __pgd_free(pgd_base); -- cgit