From nobody Wed Apr 8 03:07:14 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ACEB1C433FE for ; Fri, 21 Oct 2022 16:40:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231443AbiJUQks (ORCPT ); Fri, 21 Oct 2022 12:40:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231181AbiJUQjH (ORCPT ); Fri, 21 Oct 2022 12:39:07 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9C02128B187 for ; Fri, 21 Oct 2022 09:37:48 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id n6-20020a5b0486000000b006aff8dc9865so3737759ybp.11 for ; Fri, 21 Oct 2022 09:37:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=+C7/ATuUriMIrUw34NjzRIATqKexU0rnzCYq9OSaiU4=; b=jJGO9Z7ZWa3ry6jjj7ApkjoGMgyzlebjLJ9uIX3/IGcrm79tNXbnUjUmPWEAbUWcEd 55DuEMpVP9519fDyAuDBtSlqfbKbDKkyB8ijR8pErjYk3LLzCP/D/GV/wZwetPTE7Ojr wpMDqo/jZbCPsmNcIrkWDF+SByqBvmoi+4RjlGJDBYF3ZdmqeeL+CbWAQiFjQNnor9LY 8qVv18b9TvK+Uf6pPv8vBqeHpFR9pTHLq1xNH9bPPuK8OH77Q8JvguOlKR7a9IFK3m+x IXO0PqqgFybb/i1Kn8jmukXUloBrvY5XjEr+pUxja4P0YbG1JGN8wCpY7Bj9c2UzEM8m BOcA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=+C7/ATuUriMIrUw34NjzRIATqKexU0rnzCYq9OSaiU4=; b=uiTNWqPQYKpD8lltgshhmlRq3/grOOEv7X7NyJI7d7ZNEcgirwSv7Wf0W02B/JiSaV 7xIyurw/Zmn8/ipL5nWBnWloBaorS2yMvSPB4Ll+iQVtB4eJJ1bqA61kQ53cOqQqiFx7 PtiXWyM1Gon5ApsTyfDqspIOgUA0gYL6yujJ1av05UiujqsNRLaO8PX61qTcfTnxPuMk QtBm5xD09N0GFe5odvKlhHknDWI/URB68027mH7pwsk4OJj4pl6fRhBbUcJ7rNDdmkyX Et8UL83ajadWqpW3HWGQlCItvfRDq0oxsCQ7O/MtaIL7P5t31EWQvUCn5IyNmUugTF3w 4VAA== X-Gm-Message-State: ACrzQf2Ilt5RYE2lUdITKWHGVgVEMrtSn3GNddOsH8FhSPNEl57rlY0F EVmHzwZ95fcnr66eP6WWy2gOcA5pC3liLsev X-Google-Smtp-Source: AMsMyM5P4lx4WIyqBLDAe0Bc4rPZ7u/BTYY9AuZts942sFnS05sAkglQc+I6YcdbaB2xek0CE+P143XsmtscbOX3 X-Received: from jthoughton.c.googlers.com ([fda3:e722:ac3:cc00:14:4d90:c0a8:2a4f]) (user=jthoughton job=sendgmr) by 2002:a25:b851:0:b0:6ca:2b0b:d334 with SMTP id b17-20020a25b851000000b006ca2b0bd334mr9202954ybm.104.1666370267430; Fri, 21 Oct 2022 09:37:47 -0700 (PDT) Date: Fri, 21 Oct 2022 16:36:49 +0000 In-Reply-To: <20221021163703.3218176-1-jthoughton@google.com> Mime-Version: 1.0 References: <20221021163703.3218176-1-jthoughton@google.com> X-Mailer: git-send-email 2.38.0.135.g90850a2211-goog Message-ID: <20221021163703.3218176-34-jthoughton@google.com> Subject: [RFC PATCH v2 33/47] userfaultfd: add UFFD_FEATURE_MINOR_HUGETLBFS_HGM From: James Houghton To: Mike Kravetz , Muchun Song , Peter Xu Cc: David Hildenbrand , David Rientjes , Axel Rasmussen , Mina Almasry , "Zach O'Keefe" , Manish Mishra , Naoya Horiguchi , "Dr . David Alan Gilbert" , "Matthew Wilcox (Oracle)" , Vlastimil Babka , Baolin Wang , Miaohe Lin , Yang Shi , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, James Houghton Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Userspace must provide this new feature when it calls UFFDIO_API to enable HGM. Userspace can check if the feature exists in uffdio_api.features, and if it does not exist, the kernel does not support and therefore did not enable HGM. Signed-off-by: James Houghton --- fs/userfaultfd.c | 12 +++++++++++- include/linux/userfaultfd_k.h | 7 +++++++ include/uapi/linux/userfaultfd.h | 2 ++ 3 files changed, 20 insertions(+), 1 deletion(-) diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 07c81ab3fd4d..3a3e9ef74dab 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -226,6 +226,11 @@ static inline struct uffd_msg userfault_msg(unsigned l= ong address, return msg; } =20 +bool uffd_ctx_has_hgm(struct vm_userfaultfd_ctx *ctx) +{ + return ctx->ctx->features & UFFD_FEATURE_MINOR_HUGETLBFS_HGM; +} + #ifdef CONFIG_HUGETLB_PAGE /* * Same functionality as userfaultfd_must_wait below with modifications for @@ -1954,10 +1959,15 @@ static int userfaultfd_api(struct userfaultfd_ctx *= ctx, goto err_out; /* report all available features and ioctls to userland */ uffdio_api.features =3D UFFD_API_FEATURES; + #ifndef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR uffdio_api.features &=3D ~(UFFD_FEATURE_MINOR_HUGETLBFS | UFFD_FEATURE_MINOR_SHMEM); -#endif +#ifndef CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING + uffdio_api.features &=3D ~UFFD_FEATURE_MINOR_HUGETLBFS_HGM; +#endif /* CONFIG_HUGETLB_HIGH_GRANULARITY_MAPPING */ +#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ + #ifndef CONFIG_HAVE_ARCH_USERFAULTFD_WP uffdio_api.features &=3D ~UFFD_FEATURE_PAGEFAULT_FLAG_WP; #endif diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index f07e6998bb68..d8fa37f308f7 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -162,6 +162,8 @@ static inline bool vma_can_userfault(struct vm_area_str= uct *vma, vma_is_shmem(vma); } =20 +extern bool uffd_ctx_has_hgm(struct vm_userfaultfd_ctx *); + extern int dup_userfaultfd(struct vm_area_struct *, struct list_head *); extern void dup_userfaultfd_complete(struct list_head *); =20 @@ -228,6 +230,11 @@ static inline bool userfaultfd_armed(struct vm_area_st= ruct *vma) return false; } =20 +static inline bool uffd_ctx_has_hgm(struct vm_userfaultfd_ctx *ctx) +{ + return false; +} + static inline int dup_userfaultfd(struct vm_area_struct *vma, struct list_head *l) { diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaul= tfd.h index 005e5e306266..ae8080003560 100644 --- a/include/uapi/linux/userfaultfd.h +++ b/include/uapi/linux/userfaultfd.h @@ -36,6 +36,7 @@ UFFD_FEATURE_SIGBUS | \ UFFD_FEATURE_THREAD_ID | \ UFFD_FEATURE_MINOR_HUGETLBFS | \ + UFFD_FEATURE_MINOR_HUGETLBFS_HGM | \ UFFD_FEATURE_MINOR_SHMEM | \ UFFD_FEATURE_EXACT_ADDRESS | \ UFFD_FEATURE_WP_HUGETLBFS_SHMEM) @@ -217,6 +218,7 @@ struct uffdio_api { #define UFFD_FEATURE_MINOR_SHMEM (1<<10) #define UFFD_FEATURE_EXACT_ADDRESS (1<<11) #define UFFD_FEATURE_WP_HUGETLBFS_SHMEM (1<<12) +#define UFFD_FEATURE_MINOR_HUGETLBFS_HGM (1<<13) __u64 features; =20 __u64 ioctls; --=20 2.38.0.135.g90850a2211-goog