From patchwork Tue Jun 7 07:30:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Penny Zheng X-Patchwork-Id: 12871467 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C9E87C433EF for ; Tue, 7 Jun 2022 07:33:33 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.342915.568059 (Exim 4.92) (envelope-from ) id 1nyTiM-0007DK-96; Tue, 07 Jun 2022 07:33:22 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 342915.568059; Tue, 07 Jun 2022 07:33:22 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1nyTiM-0007DD-5F; Tue, 07 Jun 2022 07:33:22 +0000 Received: by outflank-mailman (input) for mailman id 342915; Tue, 07 Jun 2022 07:33:21 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1nyTgV-00039i-FE for xen-devel@lists.xenproject.org; Tue, 07 Jun 2022 07:31:27 +0000 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by se1-gles-flk1.inumbo.com (Halon) with ESMTP id d61425d5-e633-11ec-b605-df0040e90b76; Tue, 07 Jun 2022 09:31:25 +0200 (CEST) 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 E218D143D; Tue, 7 Jun 2022 00:31:24 -0700 (PDT) Received: from a011292.shanghai.arm.com (a011292.shanghai.arm.com [10.169.190.94]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B40613F66F; Tue, 7 Jun 2022 00:31:21 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: d61425d5-e633-11ec-b605-df0040e90b76 From: Penny Zheng To: xen-devel@lists.xenproject.org Cc: wei.chen@arm.com, Penny Zheng , Andrew Cooper , George Dunlap , Jan Beulich , Julien Grall , Stefano Stabellini , Wei Liu , Penny Zheng Subject: [PATCH v6 9/9] xen: retrieve reserved pages on populate_physmap Date: Tue, 7 Jun 2022 15:30:31 +0800 Message-Id: <20220607073031.722174-10-Penny.Zheng@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220607073031.722174-1-Penny.Zheng@arm.com> References: <20220607073031.722174-1-Penny.Zheng@arm.com> MIME-Version: 1.0 When a static domain populates memory through populate_physmap at runtime, it shall retrieve reserved pages from resv_page_list to make sure that guest RAM is still restricted in statically configured memory regions. This commit also introduces a new helper acquire_reserved_page to make it work. Signed-off-by: Penny Zheng --- v6 changes: - drop the lock before returning --- v5 changes: - extract common codes for assigning pages into a helper assign_domstatic_pages - refine commit message - remove stub function acquire_reserved_page - Alloc/free of memory can happen concurrently. So access to rsv_page_list needs to be protected with a spinlock --- v4 changes： - miss dropping __init in acquire_domstatic_pages - add the page back to the reserved list in case of error - remove redundant printk - refine log message and make it warn level --- v3 changes: - move is_domain_using_staticmem to the common header file - remove #ifdef CONFIG_STATIC_MEMORY-ary - remove meaningless page_to_mfn(page) in error log --- v2 changes: - introduce acquire_reserved_page to retrieve reserved pages from resv_page_list - forbid non-zero-order requests in populate_physmap - let is_domain_static return ((void)(d), false) on x86 --- xen/common/memory.c | 23 ++++++++++++++ xen/common/page_alloc.c | 70 +++++++++++++++++++++++++++++++---------- xen/include/xen/mm.h | 1 + 3 files changed, 77 insertions(+), 17 deletions(-) diff --git a/xen/common/memory.c b/xen/common/memory.c index f2d009843a..cb330ce877 100644 --- a/xen/common/memory.c +++ b/xen/common/memory.c @@ -245,6 +245,29 @@ static void populate_physmap(struct memop_args *a) mfn = _mfn(gpfn); } + else if ( is_domain_using_staticmem(d) ) + { + /* + * No easy way to guarantee the retrieved pages are contiguous, + * so forbid non-zero-order requests here. + */ + if ( a->extent_order != 0 ) + { + gdprintk(XENLOG_WARNING, + "Cannot allocate static order-%u pages for static %pd\n", + a->extent_order, d); + goto out; + } + + mfn = acquire_reserved_page(d, a->memflags); + if ( mfn_eq(mfn, INVALID_MFN) ) + { + gdprintk(XENLOG_WARNING, + "%pd: failed to retrieve a reserved page\n", + d); + goto out; + } + } else { page = alloc_domheap_pages(d, a->extent_order, a->memflags); diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c index 9004dd41c1..57d28304df 100644 --- a/xen/common/page_alloc.c +++ b/xen/common/page_alloc.c @@ -2661,9 +2661,8 @@ void free_staticmem_pages(struct page_info *pg, unsigned long nr_mfns, } } -static bool __init prepare_staticmem_pages(struct page_info *pg, - unsigned long nr_mfns, - unsigned int memflags) +static bool prepare_staticmem_pages(struct page_info *pg, unsigned long nr_mfns, + unsigned int memflags) { bool need_tlbflush = false; uint32_t tlbflush_timestamp = 0; @@ -2744,21 +2743,9 @@ static struct page_info * __init acquire_staticmem_pages(mfn_t smfn, return pg; } -/* - * Acquire nr_mfns contiguous pages, starting at #smfn, of static memory, - * then assign them to one specific domain #d. - */ -int __init acquire_domstatic_pages(struct domain *d, mfn_t smfn, - unsigned int nr_mfns, unsigned int memflags) +static int assign_domstatic_pages(struct domain *d, struct page_info *pg, + unsigned int nr_mfns, unsigned int memflags) { - struct page_info *pg; - - ASSERT(!in_irq()); - - pg = acquire_staticmem_pages(smfn, nr_mfns, memflags); - if ( !pg ) - return -ENOENT; - if ( !d || (memflags & (MEMF_no_owner | MEMF_no_refcount)) ) { /* @@ -2777,6 +2764,55 @@ int __init acquire_domstatic_pages(struct domain *d, mfn_t smfn, return 0; } + +/* + * Acquire nr_mfns contiguous pages, starting at #smfn, of static memory, + * then assign them to one specific domain #d. + */ +int __init acquire_domstatic_pages(struct domain *d, mfn_t smfn, + unsigned int nr_mfns, unsigned int memflags) +{ + struct page_info *pg; + + ASSERT(!in_irq()); + + pg = acquire_staticmem_pages(smfn, nr_mfns, memflags); + if ( !pg ) + return -ENOENT; + + if ( assign_domstatic_pages(d, pg, nr_mfns, memflags) ) + return -EINVAL; + + return 0; +} + +/* + * Acquire a page from reserved page list(resv_page_list), when populating + * memory for static domain on runtime. + */ +mfn_t acquire_reserved_page(struct domain *d, unsigned int memflags) +{ + struct page_info *page; + + spin_lock(&d->page_alloc_lock); + /* Acquire a page from reserved page list(resv_page_list). */ + page = page_list_remove_head(&d->resv_page_list); + spin_unlock(&d->page_alloc_lock); + if ( unlikely(!page) ) + return INVALID_MFN; + + if ( !prepare_staticmem_pages(page, 1, memflags) ) + goto fail; + + if ( assign_domstatic_pages(d, page, 1, memflags) ) + goto fail; + + return page_to_mfn(page); + + fail: + page_list_add_tail(page, &d->resv_page_list); + return INVALID_MFN; +} #endif /* diff --git a/xen/include/xen/mm.h b/xen/include/xen/mm.h index e80b4bdcde..e100151e50 100644 --- a/xen/include/xen/mm.h +++ b/xen/include/xen/mm.h @@ -90,6 +90,7 @@ void free_staticmem_pages(struct page_info *pg, unsigned long nr_mfns, bool need_scrub); int acquire_domstatic_pages(struct domain *d, mfn_t smfn, unsigned int nr_mfns, unsigned int memflags); +mfn_t acquire_reserved_page(struct domain *d, unsigned int memflags); /* Map machine page range in Xen virtual address space. */ int map_pages_to_xen(