From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1300B3B4EA9 for ; Wed, 18 Mar 2026 10:07:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773828455; cv=none; b=pB11xxbVbGs0IJcnfy7I3wb4Tqthvt81tidgHR4VbqZtW0LrZAEWcZewk0BILqMuwnTNftl4xI8GQMVHJCZInCQg5UbSfeXyc8MJhe62Yv6BmtVNYsMFUBAlyYtY18WsJCPkVu+JipQZu1eRYgJAttQBsObsmPFst7/fNevy2d0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773828455; c=relaxed/simple; bh=pMyl4Ufh9T5TtAIiLiS9RhG+aMZlyr1MsjAFPylQCPo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=np3SGQ43Zj2lVMTXx/tWxPRMhnnWPkxmfftEnIAucE7SvlGC+iOnNvRYFh5mA+xRY3Q0LC80px2Y9+09dBHwm0Igkb5Zkya3ZdzVu1mHhGXm7BuYEt06PtgCs9MRf77/UMlnfsh7m3AZWKANPJ+QhwIa+5UW92NqitrJHTURAjA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1463A1E7D; Wed, 18 Mar 2026 03:07:24 -0700 (PDT) Received: from [10.163.178.172] (unknown [10.163.178.172]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D739A3F778; Wed, 18 Mar 2026 03:07:27 -0700 (PDT) Message-ID: <1978ee53-1cb7-4bc2-a205-813f26a11076@arm.com> Date: Wed, 18 Mar 2026 15:37:24 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] arm64: mm: Use generic enum pgtable_level To: Kevin Brodsky , linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, "David Hildenbrand (Arm)" , Ryan Roberts , Catalin Marinas , Will Deacon References: <20260318092543.73331-1-kevin.brodsky@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20260318092543.73331-1-kevin.brodsky@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 18/03/26 2:55 PM, Kevin Brodsky wrote: > enum pgtable_type was introduced for arm64 by commit c64f46ee1377 > ("arm64: mm: use enum to identify pgtable level instead of > *_SHIFT"). In the meantime, the generic enum pgtable_level got > introduced by commit b22cc9a9c7ff ("mm/rmap: convert "enum > rmap_level" to "enum pgtable_level""). > > Let's switch to the generic enum pgtable_level. The only difference > is that it also includes PGD level; __pgd_pgtable_alloc() isn't > expected to create PGD tables so we add a VM_WARN_ON() for that > case. > > Suggested-by: David Hildenbrand (Arm) > Reviewed-by: David Hildenbrand (Arm) > Reviewed-by: Ryan Roberts > Signed-off-by: Kevin Brodsky Reviewed-by: Anshuman Khandual > --- > v1..v2: > - Add a VM_WARN_ON() for PGD in __pgd_pgtable_alloc() [Ryan, David] > > Cc: Catalin Marinas > Cc: Will Deacon > --- > arch/arm64/include/asm/mmu.h | 7 ----- > arch/arm64/mm/mmu.c | 59 +++++++++++++++++++----------------- > 2 files changed, 31 insertions(+), 35 deletions(-) > > diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h > index 137a173df1ff..f28e6e215da4 100644 > --- a/arch/arm64/include/asm/mmu.h > +++ b/arch/arm64/include/asm/mmu.h > @@ -17,13 +17,6 @@ > #include > #include > > -enum pgtable_type { > - TABLE_PTE, > - TABLE_PMD, > - TABLE_PUD, > - TABLE_P4D, > -}; > - > typedef struct { > atomic64_t id; > #ifdef CONFIG_COMPAT > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index a6a00accf4f9..c45a6a47dad0 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -112,7 +112,7 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, > } > EXPORT_SYMBOL(phys_mem_access_prot); > > -static phys_addr_t __init early_pgtable_alloc(enum pgtable_type pgtable_type) > +static phys_addr_t __init early_pgtable_alloc(enum pgtable_level pgtable_level) > { > phys_addr_t phys; > > @@ -197,7 +197,7 @@ static void init_pte(pte_t *ptep, unsigned long addr, unsigned long end, > static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, > unsigned long end, phys_addr_t phys, > pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), > int flags) > { > unsigned long next; > @@ -212,7 +212,7 @@ static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, > if (flags & NO_EXEC_MAPPINGS) > pmdval |= PMD_TABLE_PXN; > BUG_ON(!pgtable_alloc); > - pte_phys = pgtable_alloc(TABLE_PTE); > + pte_phys = pgtable_alloc(PGTABLE_LEVEL_PTE); > if (pte_phys == INVALID_PHYS_ADDR) > return -ENOMEM; > ptep = pte_set_fixmap(pte_phys); > @@ -252,7 +252,7 @@ static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, > > static int init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end, > phys_addr_t phys, pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags) > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), int flags) > { > unsigned long next; > > @@ -292,7 +292,7 @@ static int init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end, > static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, > unsigned long end, phys_addr_t phys, > pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), > int flags) > { > int ret; > @@ -311,7 +311,7 @@ static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, > if (flags & NO_EXEC_MAPPINGS) > pudval |= PUD_TABLE_PXN; > BUG_ON(!pgtable_alloc); > - pmd_phys = pgtable_alloc(TABLE_PMD); > + pmd_phys = pgtable_alloc(PGTABLE_LEVEL_PMD); > if (pmd_phys == INVALID_PHYS_ADDR) > return -ENOMEM; > pmdp = pmd_set_fixmap(pmd_phys); > @@ -349,7 +349,7 @@ static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, > > static int alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, > phys_addr_t phys, pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), > int flags) > { > int ret = 0; > @@ -364,7 +364,7 @@ static int alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, > if (flags & NO_EXEC_MAPPINGS) > p4dval |= P4D_TABLE_PXN; > BUG_ON(!pgtable_alloc); > - pud_phys = pgtable_alloc(TABLE_PUD); > + pud_phys = pgtable_alloc(PGTABLE_LEVEL_PUD); > if (pud_phys == INVALID_PHYS_ADDR) > return -ENOMEM; > pudp = pud_set_fixmap(pud_phys); > @@ -415,7 +415,7 @@ static int alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end, > > static int alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, > phys_addr_t phys, pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), > int flags) > { > int ret; > @@ -430,7 +430,7 @@ static int alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, > if (flags & NO_EXEC_MAPPINGS) > pgdval |= PGD_TABLE_PXN; > BUG_ON(!pgtable_alloc); > - p4d_phys = pgtable_alloc(TABLE_P4D); > + p4d_phys = pgtable_alloc(PGTABLE_LEVEL_P4D); > if (p4d_phys == INVALID_PHYS_ADDR) > return -ENOMEM; > p4dp = p4d_set_fixmap(p4d_phys); > @@ -467,7 +467,7 @@ static int alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end, > static int __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys, > unsigned long virt, phys_addr_t size, > pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), > int flags) > { > int ret; > @@ -500,7 +500,7 @@ static int __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys, > static int __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, > unsigned long virt, phys_addr_t size, > pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), > int flags) > { > int ret; > @@ -516,7 +516,7 @@ static int __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, > static void early_create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, > unsigned long virt, phys_addr_t size, > pgprot_t prot, > - phys_addr_t (*pgtable_alloc)(enum pgtable_type), > + phys_addr_t (*pgtable_alloc)(enum pgtable_level), > int flags) > { > int ret; > @@ -528,7 +528,7 @@ static void early_create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys, > } > > static phys_addr_t __pgd_pgtable_alloc(struct mm_struct *mm, gfp_t gfp, > - enum pgtable_type pgtable_type) > + enum pgtable_level pgtable_level) > { > /* Page is zeroed by init_clear_pgtable() so don't duplicate effort. */ > struct ptdesc *ptdesc = pagetable_alloc(gfp & ~__GFP_ZERO, 0); > @@ -539,40 +539,43 @@ static phys_addr_t __pgd_pgtable_alloc(struct mm_struct *mm, gfp_t gfp, > > pa = page_to_phys(ptdesc_page(ptdesc)); > > - switch (pgtable_type) { > - case TABLE_PTE: > + switch (pgtable_level) { > + case PGTABLE_LEVEL_PTE: > BUG_ON(!pagetable_pte_ctor(mm, ptdesc)); > break; > - case TABLE_PMD: > + case PGTABLE_LEVEL_PMD: > BUG_ON(!pagetable_pmd_ctor(mm, ptdesc)); > break; > - case TABLE_PUD: > + case PGTABLE_LEVEL_PUD: > pagetable_pud_ctor(ptdesc); > break; > - case TABLE_P4D: > + case PGTABLE_LEVEL_P4D: > pagetable_p4d_ctor(ptdesc); > break; > + case PGTABLE_LEVEL_PGD: > + VM_WARN_ON(1); > + break; > } > > return pa; > } > > static phys_addr_t > -pgd_pgtable_alloc_init_mm_gfp(enum pgtable_type pgtable_type, gfp_t gfp) > +pgd_pgtable_alloc_init_mm_gfp(enum pgtable_level pgtable_level, gfp_t gfp) > { > - return __pgd_pgtable_alloc(&init_mm, gfp, pgtable_type); > + return __pgd_pgtable_alloc(&init_mm, gfp, pgtable_level); > } > > static phys_addr_t __maybe_unused > -pgd_pgtable_alloc_init_mm(enum pgtable_type pgtable_type) > +pgd_pgtable_alloc_init_mm(enum pgtable_level pgtable_level) > { > - return pgd_pgtable_alloc_init_mm_gfp(pgtable_type, GFP_PGTABLE_KERNEL); > + return pgd_pgtable_alloc_init_mm_gfp(pgtable_level, GFP_PGTABLE_KERNEL); > } > > static phys_addr_t > -pgd_pgtable_alloc_special_mm(enum pgtable_type pgtable_type) > +pgd_pgtable_alloc_special_mm(enum pgtable_level pgtable_level) > { > - return __pgd_pgtable_alloc(NULL, GFP_PGTABLE_KERNEL, pgtable_type); > + return __pgd_pgtable_alloc(NULL, GFP_PGTABLE_KERNEL, pgtable_level); > } > > static void split_contpte(pte_t *ptep) > @@ -593,7 +596,7 @@ static int split_pmd(pmd_t *pmdp, pmd_t pmd, gfp_t gfp, bool to_cont) > pte_t *ptep; > int i; > > - pte_phys = pgd_pgtable_alloc_init_mm_gfp(TABLE_PTE, gfp); > + pte_phys = pgd_pgtable_alloc_init_mm_gfp(PGTABLE_LEVEL_PTE, gfp); > if (pte_phys == INVALID_PHYS_ADDR) > return -ENOMEM; > ptep = (pte_t *)phys_to_virt(pte_phys); > @@ -638,7 +641,7 @@ static int split_pud(pud_t *pudp, pud_t pud, gfp_t gfp, bool to_cont) > pmd_t *pmdp; > int i; > > - pmd_phys = pgd_pgtable_alloc_init_mm_gfp(TABLE_PMD, gfp); > + pmd_phys = pgd_pgtable_alloc_init_mm_gfp(PGTABLE_LEVEL_PMD, gfp); > if (pmd_phys == INVALID_PHYS_ADDR) > return -ENOMEM; > pmdp = (pmd_t *)phys_to_virt(pmd_phys); > @@ -1226,7 +1229,7 @@ static void __init declare_vma(struct vm_struct *vma, > > static phys_addr_t kpti_ng_temp_alloc __initdata; > > -static phys_addr_t __init kpti_ng_pgd_alloc(enum pgtable_type type) > +static phys_addr_t __init kpti_ng_pgd_alloc(enum pgtable_level pgtable_level) > { > kpti_ng_temp_alloc -= PAGE_SIZE; > return kpti_ng_temp_alloc;