From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Subject: Re: [PATCH v4 05/34] mm: add utility functions for ptdesc Date: Wed, 14 Jun 2023 16:48:08 +0300 Message-ID: <20230614134808.GD52412@kernel.org> References: <20230612210423.18611-1-vishal.moola@gmail.com> <20230612210423.18611-6-vishal.moola@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=wjxkXWxdQesbczDAjlMoUIUp5aORFN/Rt2qhtsiwT2E=; b=QULNl7focNhhL9 L91hey/6yBQWJdSLbKkMn6ktl3lRT/pDIu5zVPsF+H9JsAXkOXG7Wh0541vhQbRDMeAY6edhS3nhY iXI8Im9JyRle+xEPleN7ksdp0Lqcumag8bzGw7aovp+UoA3HRjI4wKRla4o1+LhuYOpZPyMxchRxG xOD+dCdjRD0Z4rCnAvKdXKAP5L8QfCZC2zR+y5vyJL7gyODNkfZOM7BJgRWSsBPSYlKraJiMNhRW0 HfRU0dDEvMrYv1kay4a1+la4t3tuwxMOqITZhWOmy4vUo15ZHNkIr3zDfuDKt/DC59NDnLJD8hqkR 2tzcK3JLZ3B8POygsnCA==; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686750524; bh=gxU3ouGWBBmqmAiLv/xnL0DeuSWekXdjsP3njBIM/3U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=V0QZDgjJL3QgE9x8JUspdTbfMfs3pMGIVLLZECZJRsEFY8NLOU3FHa9eCro1DbTQG /FeNyJHOZk4eWdOp9Qm7YkJcLLJo0ck5GXNz5h3cPjiltj6wJSpNYi/mUUybLAseJG L8jXEpIhrSeK1arYk58jkb8ZY9oXqo8PxB0L2CeXKQzmY6lKQeLK4aPo3LbQYz+RlD 4VPsZDkobDvZkcDjfmrkEBjkp93jW2mXHfVUlKBD7ewu+WoTI6jTDRezExZmibSP75 rhMOAusVyZKPnHJ6/AZh/X/iBtHCxp2v/1z1wxzagOqeVMLIVnG7qjazCHaREz+Nj1 kDrhr4zp2JnYA== Content-Disposition: inline In-Reply-To: <20230612210423.18611-6-vishal.moola@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+glpr-linux-riscv=m.gmane-mx.org@lists.infradead.org To: "Vishal Moola (Oracle)" Cc: Andrew Morton , Matthew Wilcox , linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, Hugh Dickins On Mon, Jun 12, 2023 at 02:03:54PM -0700, Vishal Moola (Oracle) wrote: > Introduce utility functions setting the foundation for ptdescs. These > will also assist in the splitting out of ptdesc from struct page. > > Functions that focus on the descriptor are prefixed with ptdesc_* while > functions that focus on the pagetable are prefixed with pagetable_*. > > pagetable_alloc() is defined to allocate new ptdesc pages as compound > pages. This is to standardize ptdescs by allowing for one allocation > and one free function, in contrast to 2 allocation and 2 free functions. > > Signed-off-by: Vishal Moola (Oracle) > --- > include/asm-generic/tlb.h | 11 +++++++ > include/linux/mm.h | 61 +++++++++++++++++++++++++++++++++++++++ > include/linux/pgtable.h | 12 ++++++++ > 3 files changed, 84 insertions(+) > > diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h > index b46617207c93..6bade9e0e799 100644 > --- a/include/asm-generic/tlb.h > +++ b/include/asm-generic/tlb.h > @@ -481,6 +481,17 @@ static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page) > return tlb_remove_page_size(tlb, page, PAGE_SIZE); > } > > +static inline void tlb_remove_ptdesc(struct mmu_gather *tlb, void *pt) > +{ > + tlb_remove_table(tlb, pt); > +} > + > +/* Like tlb_remove_ptdesc, but for page-like page directories. */ > +static inline void tlb_remove_page_ptdesc(struct mmu_gather *tlb, struct ptdesc *pt) > +{ > + tlb_remove_page(tlb, ptdesc_page(pt)); > +} > + > static inline void tlb_change_page_size(struct mmu_gather *tlb, > unsigned int page_size) > { > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 0db09639dd2d..f184f1eba85d 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -2766,6 +2766,62 @@ static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long a > } > #endif /* CONFIG_MMU */ > > +static inline struct ptdesc *virt_to_ptdesc(const void *x) > +{ > + return page_ptdesc(virt_to_page(x)); > +} > + > +static inline void *ptdesc_to_virt(const struct ptdesc *pt) > +{ > + return page_to_virt(ptdesc_page(pt)); > +} > + > +static inline void *ptdesc_address(const struct ptdesc *pt) > +{ > + return folio_address(ptdesc_folio(pt)); > +} > + > +static inline bool pagetable_is_reserved(struct ptdesc *pt) > +{ > + return folio_test_reserved(ptdesc_folio(pt)); > +} > + > +/** > + * pagetable_alloc - Allocate pagetables > + * @gfp: GFP flags > + * @order: desired pagetable order > + * > + * pagetable_alloc allocates a page table descriptor as well as all pages > + * described by it. I think the order should be switched here to emphasize that primarily this method allocates memory for page tables. How about pagetable_alloc allocates memory for the page tables as well as a page table descriptor that describes the allocated memory > + * > + * Return: The ptdesc describing the allocated page tables. > + */ > +static inline struct ptdesc *pagetable_alloc(gfp_t gfp, unsigned int order) > +{ > + struct page *page = alloc_pages(gfp | __GFP_COMP, order); > + > + return page_ptdesc(page); > +} > + > +/** > + * pagetable_free - Free pagetables > + * @pt: The page table descriptor > + * > + * pagetable_free frees a page table descriptor as well as all page > + * tables described by said ptdesc. Similarly here. > + */ > +static inline void pagetable_free(struct ptdesc *pt) > +{ > + struct page *page = ptdesc_page(pt); > + > + __free_pages(page, compound_order(page)); > +} > + > +static inline void pagetable_clear(void *x) > +{ > + clear_page(x); > +} > + > #if USE_SPLIT_PTE_PTLOCKS > #if ALLOC_SPLIT_PTLOCKS > void __init ptlock_cache_init(void); > @@ -2992,6 +3048,11 @@ static inline void mark_page_reserved(struct page *page) > adjust_managed_page_count(page, -1); > } > > +static inline void free_reserved_ptdesc(struct ptdesc *pt) > +{ > + free_reserved_page(ptdesc_page(pt)); > +} > + > /* > * Default method to free all the __init memory into the buddy system. > * The freed pages will be poisoned with pattern "poison" if it's within > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index 330de96ebfd6..c405f74d3875 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -1026,6 +1026,18 @@ TABLE_MATCH(ptl, ptl); > #undef TABLE_MATCH > static_assert(sizeof(struct ptdesc) <= sizeof(struct page)); > > +#define ptdesc_page(pt) (_Generic((pt), \ > + const struct ptdesc *: (const struct page *)(pt), \ > + struct ptdesc *: (struct page *)(pt))) > + > +#define ptdesc_folio(pt) (_Generic((pt), \ > + const struct ptdesc *: (const struct folio *)(pt), \ > + struct ptdesc *: (struct folio *)(pt))) > + > +#define page_ptdesc(p) (_Generic((p), \ > + const struct page *: (const struct ptdesc *)(p), \ > + struct page *: (struct ptdesc *)(p))) > + > /* > * No-op macros that just return the current protection value. Defined here > * because these macros can be used even if CONFIG_MMU is not defined. > -- > 2.40.1 > > -- Sincerely yours, Mike.