From patchwork Fri Nov 1 08:39:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 11222659 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E78321390 for ; Fri, 1 Nov 2019 08:41:10 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 98F75217D9 for ; Fri, 1 Nov 2019 08:41:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="s9ggOOTG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 98F75217D9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C2CAF6B0005; Fri, 1 Nov 2019 04:41:09 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id BDCE56B0010; Fri, 1 Nov 2019 04:41:09 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ACBCC6B0266; Fri, 1 Nov 2019 04:41:09 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0145.hostedemail.com [216.40.44.145]) by kanga.kvack.org (Postfix) with ESMTP id 7D7B96B0005 for ; Fri, 1 Nov 2019 04:41:09 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id 1DCE75831 for ; Fri, 1 Nov 2019 08:41:09 +0000 (UTC) X-FDA: 76107063858.25.mask58_6146404d1d720 X-Spam-Summary: 2,0,0,de4fbf70d5a83a69,d41d8cd98f00b204,rppt@kernel.org,::akpm@linux-foundation.org:anton.ivanov@cambridgegreys.com:arnd@arndb.de:davem@davemloft.net:geert@linux-m68k.org:green.hu@gmail.com:gerg@linux-m68k.org:deller@gmx.de:james.bottomley@hansenpartnership.com:jdike@addtoit.com:kirill@shutemov.name:torvalds@linux-foundation.org:msalter@redhat.com:mattst88@gmail.com:monstr@monstr.eu:peda@axentia.se:richard@nod.at:eike-kernel@sf-tec.de:linux@armlinux.org.uk:sammy@sammy.net:deanbo422@gmail.com:vineet.gupta1@synopsys.com:rppt@kernel.org:linux-alpha@vger.kernel.org:linux-arch@vger.kernel.org:linux-arm-kernel@lists.infradead.org:linux-c6x-dev@linux-c6x.org:linux-kernel@vger.kernel.org:linux-m68k@lists.linux-m68k.org:linux-parisc@vger.kernel.org:linux-um@lists.infradead.org:sparclinux@vger.kernel.org:rppt@linux.ibm.com,RULES_HIT:4:41:69:355:379:541:800:960:966:973:988:989:1260:1345:1359:1431:1437:1605:1730:1747:1777:1792:1981:2194:2196:2198:2199:2200:2201:2393:2553: 2559:256 X-HE-Tag: mask58_6146404d1d720 X-Filterd-Recvd-Size: 16349 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf21.hostedemail.com (Postfix) with ESMTP for ; Fri, 1 Nov 2019 08:41:08 +0000 (UTC) Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4E504218DE; Fri, 1 Nov 2019 08:40:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572597667; bh=fUgAqco8vYJcOm1T0s9V9hpIfLlR7wsDpLrunSlirY4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s9ggOOTGr2nJcTow3EYx7F9HQ5nkt+uZdVao1YPrqSG1/L75e/tAEjnxkM0jiznhb heGZIlsEju2ImA/JhUek5teoMtXsV6NjStnvDAaKbRRSTcKq/BQ2QwTLENF8lBNRaT qbS9ydPct75JDhyTWvu6KjIVA/wnqsxcZRx3JUoE= From: Mike Rapoport To: linux-mm@kvack.org Cc: Andrew Morton , Anton Ivanov , Arnd Bergmann , "David S. Miller" , Geert Uytterhoeven , Greentime Hu , Greg Ungerer , Helge Deller , "James E.J. Bottomley" , Jeff Dike , "Kirill A. Shutemov" , Linus Torvalds , Mark Salter , Matt Turner , Michal Simek , Peter Rosin , Richard Weinberger , Rolf Eike Beer , Russell King , Sam Creasey , Vincent Chen , Vineet Gupta , Mike Rapoport , linux-alpha@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-c6x-dev@linux-c6x.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-parisc@vger.kernel.org, linux-um@lists.infradead.org, sparclinux@vger.kernel.org, Mike Rapoport Subject: [PATCH v2 08/13] parisc: use pgtable-nopXd instead of 4level-fixup Date: Fri, 1 Nov 2019 10:39:39 +0200 Message-Id: <1572597584-6390-9-git-send-email-rppt@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1572597584-6390-1-git-send-email-rppt@kernel.org> References: <1572597584-6390-1-git-send-email-rppt@kernel.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Mike Rapoport parisc has two or three levels of page tables and can use appropriate pgtable-nopXd and folding of the upper layers. Replace usage of include/asm-generic/4level-fixup.h and explicit definitions of __PAGETABLE_PxD_FOLDED in parisc with include/asm-generic/pgtable-nopmd.h for two-level configurations and with include/asm-generic/pgtable-nopud.h for three-lelve configurations and adjust page table manipulation macros and functions accordingly. Signed-off-by: Mike Rapoport Acked-by: Helge Deller --- arch/parisc/include/asm/page.h | 30 +++++++++++++--------- arch/parisc/include/asm/pgalloc.h | 41 +++++++++++------------------- arch/parisc/include/asm/pgtable.h | 52 +++++++++++++++++++-------------------- arch/parisc/include/asm/tlb.h | 2 ++ arch/parisc/kernel/cache.c | 13 ++++++---- arch/parisc/kernel/pci-dma.c | 9 +++++-- arch/parisc/mm/fixmap.c | 10 +++++--- 7 files changed, 81 insertions(+), 76 deletions(-) diff --git a/arch/parisc/include/asm/page.h b/arch/parisc/include/asm/page.h index 93caf17..796ae29 100644 --- a/arch/parisc/include/asm/page.h +++ b/arch/parisc/include/asm/page.h @@ -42,48 +42,54 @@ typedef struct { unsigned long pte; } pte_t; /* either 32 or 64bit */ /* NOTE: even on 64 bits, these entries are __u32 because we allocate * the pmd and pgd in ZONE_DMA (i.e. under 4GB) */ -typedef struct { __u32 pmd; } pmd_t; typedef struct { __u32 pgd; } pgd_t; typedef struct { unsigned long pgprot; } pgprot_t; -#define pte_val(x) ((x).pte) -/* These do not work lvalues, so make sure we don't use them as such. */ +#if CONFIG_PGTABLE_LEVELS == 3 +typedef struct { __u32 pmd; } pmd_t; +#define __pmd(x) ((pmd_t) { (x) } ) +/* pXd_val() do not work as lvalues, so make sure we don't use them as such. */ #define pmd_val(x) ((x).pmd + 0) +#endif + +#define pte_val(x) ((x).pte) #define pgd_val(x) ((x).pgd + 0) #define pgprot_val(x) ((x).pgprot) #define __pte(x) ((pte_t) { (x) } ) -#define __pmd(x) ((pmd_t) { (x) } ) #define __pgd(x) ((pgd_t) { (x) } ) #define __pgprot(x) ((pgprot_t) { (x) } ) -#define __pmd_val_set(x,n) (x).pmd = (n) -#define __pgd_val_set(x,n) (x).pgd = (n) - #else /* * .. while these make it easier on the compiler */ typedef unsigned long pte_t; + +#if CONFIG_PGTABLE_LEVELS == 3 typedef __u32 pmd_t; +#define pmd_val(x) (x) +#define __pmd(x) (x) +#endif + typedef __u32 pgd_t; typedef unsigned long pgprot_t; #define pte_val(x) (x) -#define pmd_val(x) (x) #define pgd_val(x) (x) #define pgprot_val(x) (x) #define __pte(x) (x) -#define __pmd(x) (x) #define __pgd(x) (x) #define __pgprot(x) (x) -#define __pmd_val_set(x,n) (x) = (n) -#define __pgd_val_set(x,n) (x) = (n) - #endif /* STRICT_MM_TYPECHECKS */ +#define set_pmd(pmdptr, pmdval) (*(pmdptr) = (pmdval)) +#if CONFIG_PGTABLE_LEVELS == 3 +#define set_pud(pudptr, pudval) (*(pudptr) = (pudval)) +#endif + typedef struct page *pgtable_t; typedef struct __physmem_range { diff --git a/arch/parisc/include/asm/pgalloc.h b/arch/parisc/include/asm/pgalloc.h index d98647c..9ac74da 100644 --- a/arch/parisc/include/asm/pgalloc.h +++ b/arch/parisc/include/asm/pgalloc.h @@ -34,13 +34,13 @@ static inline pgd_t *pgd_alloc(struct mm_struct *mm) /* Populate first pmd with allocated memory. We mark it * with PxD_FLAG_ATTACHED as a signal to the system that this * pmd entry may not be cleared. */ - __pgd_val_set(*actual_pgd, (PxD_FLAG_PRESENT | - PxD_FLAG_VALID | - PxD_FLAG_ATTACHED) - + (__u32)(__pa((unsigned long)pgd) >> PxD_VALUE_SHIFT)); + set_pgd(actual_pgd, __pgd((PxD_FLAG_PRESENT | + PxD_FLAG_VALID | + PxD_FLAG_ATTACHED) + + (__u32)(__pa((unsigned long)pgd) >> PxD_VALUE_SHIFT))); /* The first pmd entry also is marked with PxD_FLAG_ATTACHED as * a signal that this pmd may not be freed */ - __pgd_val_set(*pgd, PxD_FLAG_ATTACHED); + set_pgd(pgd, __pgd(PxD_FLAG_ATTACHED)); #endif } spin_lock_init(pgd_spinlock(actual_pgd)); @@ -59,10 +59,10 @@ static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) /* Three Level Page Table Support for pmd's */ -static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmd) +static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) { - __pgd_val_set(*pgd, (PxD_FLAG_PRESENT | PxD_FLAG_VALID) + - (__u32)(__pa((unsigned long)pmd) >> PxD_VALUE_SHIFT)); + set_pud(pud, __pud((PxD_FLAG_PRESENT | PxD_FLAG_VALID) + + (__u32)(__pa((unsigned long)pmd) >> PxD_VALUE_SHIFT))); } static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address) @@ -88,19 +88,6 @@ static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd) free_pages((unsigned long)pmd, PMD_ORDER); } -#else - -/* Two Level Page Table Support for pmd's */ - -/* - * allocating and freeing a pmd is trivial: the 1-entry pmd is - * inside the pgd, so has no extra memory associated with it. - */ - -#define pmd_alloc_one(mm, addr) ({ BUG(); ((pmd_t *)2); }) -#define pmd_free(mm, x) do { } while (0) -#define pgd_populate(mm, pmd, pte) BUG() - #endif static inline void @@ -110,14 +97,14 @@ pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte) /* preserve the gateway marker if this is the beginning of * the permanent pmd */ if(pmd_flag(*pmd) & PxD_FLAG_ATTACHED) - __pmd_val_set(*pmd, (PxD_FLAG_PRESENT | - PxD_FLAG_VALID | - PxD_FLAG_ATTACHED) - + (__u32)(__pa((unsigned long)pte) >> PxD_VALUE_SHIFT)); + set_pmd(pmd, __pmd((PxD_FLAG_PRESENT | + PxD_FLAG_VALID | + PxD_FLAG_ATTACHED) + + (__u32)(__pa((unsigned long)pte) >> PxD_VALUE_SHIFT))); else #endif - __pmd_val_set(*pmd, (PxD_FLAG_PRESENT | PxD_FLAG_VALID) - + (__u32)(__pa((unsigned long)pte) >> PxD_VALUE_SHIFT)); + set_pmd(pmd, __pmd((PxD_FLAG_PRESENT | PxD_FLAG_VALID) + + (__u32)(__pa((unsigned long)pte) >> PxD_VALUE_SHIFT))); } #define pmd_populate(mm, pmd, pte_page) \ diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h index 4ac374b..f0a3659 100644 --- a/arch/parisc/include/asm/pgtable.h +++ b/arch/parisc/include/asm/pgtable.h @@ -3,7 +3,12 @@ #define _PARISC_PGTABLE_H #include -#include + +#if CONFIG_PGTABLE_LEVELS == 3 +#include +#elif CONFIG_PGTABLE_LEVELS == 2 +#include +#endif #include @@ -101,8 +106,10 @@ static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr) #define pte_ERROR(e) \ printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e)) +#if CONFIG_PGTABLE_LEVELS == 3 #define pmd_ERROR(e) \ printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e)) +#endif #define pgd_ERROR(e) \ printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e)) @@ -132,19 +139,18 @@ static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr) #define PTRS_PER_PTE (1UL << BITS_PER_PTE) /* Definitions for 2nd level */ +#if CONFIG_PGTABLE_LEVELS == 3 #define PMD_SHIFT (PLD_SHIFT + BITS_PER_PTE) #define PMD_SIZE (1UL << PMD_SHIFT) #define PMD_MASK (~(PMD_SIZE-1)) -#if CONFIG_PGTABLE_LEVELS == 3 #define BITS_PER_PMD (PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY) +#define PTRS_PER_PMD (1UL << BITS_PER_PMD) #else -#define __PAGETABLE_PMD_FOLDED 1 #define BITS_PER_PMD 0 #endif -#define PTRS_PER_PMD (1UL << BITS_PER_PMD) /* Definitions for 1st level */ -#define PGDIR_SHIFT (PMD_SHIFT + BITS_PER_PMD) +#define PGDIR_SHIFT (PLD_SHIFT + BITS_PER_PTE + BITS_PER_PMD) #if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG #define BITS_PER_PGD (BITS_PER_LONG - PGDIR_SHIFT) #else @@ -317,6 +323,8 @@ extern unsigned long *empty_zero_page; #define pmd_flag(x) (pmd_val(x) & PxD_FLAG_MASK) #define pmd_address(x) ((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT) +#define pud_flag(x) (pud_val(x) & PxD_FLAG_MASK) +#define pud_address(x) ((unsigned long)(pud_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT) #define pgd_flag(x) (pgd_val(x) & PxD_FLAG_MASK) #define pgd_address(x) ((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT) @@ -334,42 +342,32 @@ static inline void pmd_clear(pmd_t *pmd) { if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED) /* This is the entry pointing to the permanent pmd * attached to the pgd; cannot clear it */ - __pmd_val_set(*pmd, PxD_FLAG_ATTACHED); + set_pmd(pmd, __pmd(PxD_FLAG_ATTACHED)); else #endif - __pmd_val_set(*pmd, 0); + set_pmd(pmd, __pmd(0)); } #if CONFIG_PGTABLE_LEVELS == 3 -#define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd))) -#define pgd_page(pgd) virt_to_page((void *)pgd_page_vaddr(pgd)) +#define pud_page_vaddr(pud) ((unsigned long) __va(pud_address(pud))) +#define pud_page(pud) virt_to_page((void *)pud_page_vaddr(pud)) /* For 64 bit we have three level tables */ -#define pgd_none(x) (!pgd_val(x)) -#define pgd_bad(x) (!(pgd_flag(x) & PxD_FLAG_VALID)) -#define pgd_present(x) (pgd_flag(x) & PxD_FLAG_PRESENT) -static inline void pgd_clear(pgd_t *pgd) { +#define pud_none(x) (!pud_val(x)) +#define pud_bad(x) (!(pud_flag(x) & PxD_FLAG_VALID)) +#define pud_present(x) (pud_flag(x) & PxD_FLAG_PRESENT) +static inline void pud_clear(pud_t *pud) { #if CONFIG_PGTABLE_LEVELS == 3 - if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED) - /* This is the permanent pmd attached to the pgd; cannot + if(pud_flag(*pud) & PxD_FLAG_ATTACHED) + /* This is the permanent pmd attached to the pud; cannot * free it */ return; #endif - __pgd_val_set(*pgd, 0); + set_pud(pud, __pud(0)); } -#else -/* - * The "pgd_xxx()" functions here are trivial for a folded two-level - * setup: the pgd is never bad, and a pmd always exists (as it's folded - * into the pgd entry) - */ -static inline int pgd_none(pgd_t pgd) { return 0; } -static inline int pgd_bad(pgd_t pgd) { return 0; } -static inline int pgd_present(pgd_t pgd) { return 1; } -static inline void pgd_clear(pgd_t * pgdp) { } #endif /* @@ -452,7 +450,7 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) #if CONFIG_PGTABLE_LEVELS == 3 #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) #define pmd_offset(dir,address) \ -((pmd_t *) pgd_page_vaddr(*(dir)) + pmd_index(address)) +((pmd_t *) pud_page_vaddr(*(dir)) + pmd_index(address)) #else #define pmd_offset(dir,addr) ((pmd_t *) dir) #endif diff --git a/arch/parisc/include/asm/tlb.h b/arch/parisc/include/asm/tlb.h index 8c0446b..44235f3 100644 --- a/arch/parisc/include/asm/tlb.h +++ b/arch/parisc/include/asm/tlb.h @@ -4,7 +4,9 @@ #include +#if CONFIG_PGTABLE_LEVELS == 3 #define __pmd_free_tlb(tlb, pmd, addr) pmd_free((tlb)->mm, pmd) +#endif #define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte) #endif diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c index a82b3ea..7b2e0ab 100644 --- a/arch/parisc/kernel/cache.c +++ b/arch/parisc/kernel/cache.c @@ -534,11 +534,14 @@ static inline pte_t *get_ptep(pgd_t *pgd, unsigned long addr) pte_t *ptep = NULL; if (!pgd_none(*pgd)) { - pud_t *pud = pud_offset(pgd, addr); - if (!pud_none(*pud)) { - pmd_t *pmd = pmd_offset(pud, addr); - if (!pmd_none(*pmd)) - ptep = pte_offset_map(pmd, addr); + p4d_t *p4d = p4d_offset(pgd, addr); + if (!p4d_none(*p4d)) { + pud_t *pud = pud_offset(p4d, addr); + if (!pud_none(*pud)) { + pmd_t *pmd = pmd_offset(pud, addr); + if (!pmd_none(*pmd)) + ptep = pte_offset_map(pmd, addr); + } } } return ptep; diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c index ca35d9a..8859c71 100644 --- a/arch/parisc/kernel/pci-dma.c +++ b/arch/parisc/kernel/pci-dma.c @@ -133,9 +133,14 @@ static inline int map_uncached_pages(unsigned long vaddr, unsigned long size, dir = pgd_offset_k(vaddr); do { + p4d_t *p4d; + pud_t *pud; pmd_t *pmd; - - pmd = pmd_alloc(NULL, dir, vaddr); + + p4d = p4d_offset(dir, vaddr); + pud = pud_offset(p4d, vaddr); + pmd = pmd_alloc(NULL, pud, vaddr); + if (!pmd) return -ENOMEM; if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr)) diff --git a/arch/parisc/mm/fixmap.c b/arch/parisc/mm/fixmap.c index 474cd24..e2d8b0a 100644 --- a/arch/parisc/mm/fixmap.c +++ b/arch/parisc/mm/fixmap.c @@ -14,11 +14,13 @@ void notrace set_fixmap(enum fixed_addresses idx, phys_addr_t phys) { unsigned long vaddr = __fix_to_virt(idx); pgd_t *pgd = pgd_offset_k(vaddr); - pmd_t *pmd = pmd_offset(pgd, vaddr); + p4d_t *p4d = p4d_offset(pgd, vaddr); + pud_t *pud = pud_offset(p4d, vaddr); + pmd_t *pmd = pmd_offset(pud, vaddr); pte_t *pte; if (pmd_none(*pmd)) - pmd = pmd_alloc(NULL, pgd, vaddr); + pmd = pmd_alloc(NULL, pud, vaddr); pte = pte_offset_kernel(pmd, vaddr); if (pte_none(*pte)) @@ -32,7 +34,9 @@ void notrace clear_fixmap(enum fixed_addresses idx) { unsigned long vaddr = __fix_to_virt(idx); pgd_t *pgd = pgd_offset_k(vaddr); - pmd_t *pmd = pmd_offset(pgd, vaddr); + p4d_t *p4d = p4d_offset(pgd, vaddr); + pud_t *pud = pud_offset(p4d, vaddr); + pmd_t *pmd = pmd_offset(pud, vaddr); pte_t *pte = pte_offset_kernel(pmd, vaddr); if (WARN_ON(pte_none(*pte)))