From mboxrd@z Thu Jan 1 00:00:00 1970 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 AEE51C61DA4 for ; Tue, 7 Feb 2023 01:29:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230262AbjBGB36 (ORCPT ); Mon, 6 Feb 2023 20:29:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229976AbjBGB3u (ORCPT ); Mon, 6 Feb 2023 20:29:50 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C780E2ED5B for ; Mon, 6 Feb 2023 17:29:48 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4EE8A610AA for ; Tue, 7 Feb 2023 01:29:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9BFDDC433EF; Tue, 7 Feb 2023 01:29:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1675733387; bh=bc3DSUqAQxMCh6xIXZVuuJY+1cZx5FdG8QcOwDg6Xo8=; h=Date:To:From:Subject:From; b=cSYZ10aMq2srf3K/pOzC2CCplz9QvEsFzQWuahTKwqdwR9qv5yd0ulLL3f5y38NR8 dBkWp7wPhmVf/RTNreapxyuXXHQP+HUuC/NsxI8SfxE5nSnw9GOVqD4asyPSOFlJ6b SIYup/ApFVPJgwQ1WWQjGmWFLHuxXxL7LtMZLnr8= Date: Mon, 06 Feb 2023 17:29:47 -0800 To: mm-commits@vger.kernel.org, rppt@kernel.org, jhubbard@nvidia.com, imbrenda@linux.ibm.com, hch@infradead.org, dhowells@redhat.com, david@redhat.com, apopple@nvidia.com, jgg@nvidia.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-gup-make-get_user_pages_fast_only-return-the-common-return-value.patch added to mm-unstable branch Message-Id: <20230207012947.9BFDDC433EF@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/gup: make get_user_pages_fast_only() return the common return value has been added to the -mm mm-unstable branch. Its filename is mm-gup-make-get_user_pages_fast_only-return-the-common-return-value.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-gup-make-get_user_pages_fast_only-return-the-common-return-value.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Jason Gunthorpe Subject: mm/gup: make get_user_pages_fast_only() return the common return value Date: Tue, 24 Jan 2023 16:34:32 -0400 There are only two callers, both can handle the common return code: - get_user_page_fast_only() checks == 1 - gfn_to_page_many_atomic() already returns -1, and the only caller checks for negative return values Remove the restriction against returning negative values. Link: https://lkml.kernel.org/r/11-v2-987e91b59705+36b-gup_tidy_jgg@nvidia.com Signed-off-by: Jason Gunthorpe Acked-by: Mike Rapoport (IBM) Reviewed-by: John Hubbard Reviewed-by: David Hildenbrand Cc: Alistair Popple Cc: Christoph Hellwig Cc: Claudio Imbrenda Cc: David Howells Signed-off-by: Andrew Morton --- --- a/mm/gup.c~mm-gup-make-get_user_pages_fast_only-return-the-common-return-value +++ a/mm/gup.c @@ -3005,8 +3005,6 @@ static int internal_get_user_pages_fast( * * Like get_user_pages_fast() except it's IRQ-safe in that it won't fall back to * the regular GUP. - * Note a difference with get_user_pages_fast: this always returns the - * number of pages pinned, 0 if no pages were pinned. * * If the architecture does not support this function, simply return with no * pages pinned. @@ -3018,7 +3016,6 @@ static int internal_get_user_pages_fast( int get_user_pages_fast_only(unsigned long start, int nr_pages, unsigned int gup_flags, struct page **pages) { - int nr_pinned; /* * Internally (within mm/gup.c), gup fast variants must set FOLL_GET, * because gup fast is always a "pin with a +1 page refcount" request. @@ -3030,19 +3027,7 @@ int get_user_pages_fast_only(unsigned lo FOLL_GET | FOLL_FAST_ONLY)) return -EINVAL; - nr_pinned = internal_get_user_pages_fast(start, nr_pages, gup_flags, - pages); - - /* - * As specified in the API description above, this routine is not - * allowed to return negative values. However, the common core - * routine internal_get_user_pages_fast() *can* return -errno. - * Therefore, correct for that here: - */ - if (nr_pinned < 0) - nr_pinned = 0; - - return nr_pinned; + return internal_get_user_pages_fast(start, nr_pages, gup_flags, pages); } EXPORT_SYMBOL_GPL(get_user_pages_fast_only); _ Patches currently in -mm which might be from jgg@nvidia.com are mm-gup-have-internal-functions-get-the-mmap_read_lock.patch mm-gup-remove-obsolete-foll_longterm-comment.patch mm-gup-dont-call-__gup_longterm_locked-if-foll_longterm-cannot-be-set.patch mm-gup-move-try_grab_page-to-mm-internalh.patch mm-gup-simplify-the-external-interface-functions-and-consolidate-invariants.patch mm-gup-add-an-assertion-that-the-mmap-lock-is-locked.patch mm-gup-remove-locked-being-null-from-faultin_vma_page_range.patch mm-gup-add-foll_unlockable.patch mm-gup-make-locked-never-null-in-the-internal-gup-functions.patch mm-gup-remove-pin_user_pages_fast_only.patch mm-gup-make-get_user_pages_fast_only-return-the-common-return-value.patch mm-gup-move-gup_must_unshare-to-mm-internalh.patch mm-gup-move-private-gup-foll_-flags-to-internalh.patch