From patchwork Fri Jul 28 16:42:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13332123 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 D1866C001DE for ; Fri, 28 Jul 2023 16:42:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229564AbjG1Qmu (ORCPT ); Fri, 28 Jul 2023 12:42:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232935AbjG1Qmr (ORCPT ); Fri, 28 Jul 2023 12:42:47 -0400 Received: from mail-il1-x12a.google.com (mail-il1-x12a.google.com [IPv6:2607:f8b0:4864:20::12a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8F9E1739 for ; Fri, 28 Jul 2023 09:42:42 -0700 (PDT) Received: by mail-il1-x12a.google.com with SMTP id e9e14a558f8ab-34770dd0b4eso1764255ab.0 for ; Fri, 28 Jul 2023 09:42:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20221208.gappssmtp.com; s=20221208; t=1690562562; x=1691167362; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=30eD9fAtYTDVQhSBmDtrnQoUWRd4/P+cYE3Me4cIvhU=; b=DKvcWZja9ydTXsU5tYZC8ODhETIbn5KR9hRed/c2NdhL4yY3uygRbDb5dDpGPIZmNR BlNzu5WNQYhZkw7Vlb+FJoMxxXJp2Rs9l5K32ZlR+xTZxOdARQ2RlK7VCgor7RzgPYFL tBNfXpcdQakAIi1W+bqEbixou2yk9uRPNjHpe9XZhRAGRiB9SGwK6GhDpm1IAzvAp2SA /xrm5m8vmVTqcRlgSiq84QIj6f/DaB7sXCbDtCd/wccBuIU80cWHRxPzjuALtRcngYb3 48Ut2CMMr0NQruQqc+pA4QQuKwIgyCIGJXIbowoUi0VKb4Pzgac8YwfH+U1niBycADs0 eQpA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690562562; x=1691167362; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=30eD9fAtYTDVQhSBmDtrnQoUWRd4/P+cYE3Me4cIvhU=; b=a+YR+7CA0I1SWCpdiqZMjUBwWDqVGen+5iIwdrRlYPq0T40eLgOlfiZ/rb9AnDPFJy 5mtdKPEjhekrvRsR89y6QVW8ajuXjdFeO/XEx1NiWSwas9pT56+pjxYmdTDbWGKDpg9e ZviMJbuUcoNFpMPuFqG1ydT/VOu9kIoxy+1vU/KI+lcBX6kDiCWkjVCFATjAGzt6C1ux qhGpxZQ5PzaSZDr+q/h9ClECUQWswzXLPoTyk05/Wl55Q5Ode1ZIJ9q2kD0Dd3sXsTCe hCO1QXa6x+9ksRxySYUSu0KrxyN8GP+EJQaQsHdYjwDG2NVDhpMXtK97qg5d9t/nl1dq z+Dg== X-Gm-Message-State: ABy/qLbCnKOUOan6GT4yhCgBT2mfBoJCCPv6/peZRPF0nGeyIfud9lW2 uN4BSF/PrHr2sCgQluIoyQMjYoWEfNcckIv8q48= X-Google-Smtp-Source: APBJJlHzPyCbNiUtQSTRO/d4Nx6b6ON2V8yqilLfWxeJXRIzcggEvl1vz3AI6uFMkgsRxm/THoi2BQ== X-Received: by 2002:a92:c64f:0:b0:346:10c5:2949 with SMTP id 15-20020a92c64f000000b0034610c52949mr66624ill.1.1690562561891; Fri, 28 Jul 2023 09:42:41 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id b2-20020a029a02000000b0042b37dda71asm1158808jal.136.2023.07.28.09.42.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Jul 2023 09:42:41 -0700 (PDT) From: Jens Axboe To: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterz@infradead.org, andres@anarazel.de, tglx@linutronix.de, Jens Axboe Subject: [PATCH 03/12] futex: Flag conversion Date: Fri, 28 Jul 2023 10:42:26 -0600 Message-Id: <20230728164235.1318118-4-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230728164235.1318118-1-axboe@kernel.dk> References: <20230728164235.1318118-1-axboe@kernel.dk> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org From: Peter Zijlstra Futex has 3 sets of flags: - legacy futex op bits - futex2 flags - internal flags Add a few helpers to convert from the API flags into the internal flags. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Jens Axboe --- kernel/futex/futex.h | 64 +++++++++++++++++++++++++++++++++++++++-- kernel/futex/syscalls.c | 24 ++++++---------- kernel/futex/waitwake.c | 4 +-- 3 files changed, 72 insertions(+), 20 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index b5379c0e6d6d..c0e04599904a 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -5,6 +5,7 @@ #include #include #include +#include #ifdef CONFIG_PREEMPT_RT #include @@ -16,8 +17,15 @@ * Futex flags used to encode options to functions and preserve them across * restarts. */ +#define FLAGS_SIZE_8 0x00 +#define FLAGS_SIZE_16 0x01 +#define FLAGS_SIZE_32 0x02 +#define FLAGS_SIZE_64 0x03 + +#define FLAGS_SIZE_MASK 0x03 + #ifdef CONFIG_MMU -# define FLAGS_SHARED 0x01 +# define FLAGS_SHARED 0x10 #else /* * NOMMU does not have per process address space. Let the compiler optimize @@ -25,8 +33,58 @@ */ # define FLAGS_SHARED 0x00 #endif -#define FLAGS_CLOCKRT 0x02 -#define FLAGS_HAS_TIMEOUT 0x04 +#define FLAGS_CLOCKRT 0x20 +#define FLAGS_HAS_TIMEOUT 0x40 +#define FLAGS_NUMA 0x80 + +/* FUTEX_ to FLAGS_ */ +static inline unsigned int futex_to_flags(unsigned int op) +{ + unsigned int flags = FLAGS_SIZE_32; + + if (!(op & FUTEX_PRIVATE_FLAG)) + flags |= FLAGS_SHARED; + + if (op & FUTEX_CLOCK_REALTIME) + flags |= FLAGS_CLOCKRT; + + return flags; +} + +/* FUTEX2_ to FLAGS_ */ +static inline unsigned int futex2_to_flags(unsigned int flags2) +{ + unsigned int flags = flags2 & FUTEX2_64; + + if (!(flags2 & FUTEX2_PRIVATE)) + flags |= FLAGS_SHARED; + + if (flags2 & FUTEX2_NUMA) + flags |= FLAGS_NUMA; + + return flags; +} + +static inline bool futex_flags_valid(unsigned int flags) +{ + /* Only 64bit futexes for 64bit code */ + if (!IS_ENABLED(CONFIG_64BIT) || in_compat_syscall()) { + if ((flags & FLAGS_SIZE_MASK) == FLAGS_SIZE_64) + return false; + } + + /* Only 32bit futexes are implemented -- for now */ + if ((flags & FLAGS_SIZE_MASK) != FLAGS_SIZE_32) + return false; + + return true; +} + +static inline unsigned int futex_size(unsigned int flags) +{ + unsigned int size = flags & FLAGS_SIZE_MASK; + return 1 << size; /* {0,1,2,3} -> {1,2,4,8} */ +} #ifdef CONFIG_FAIL_FUTEX extern bool should_fail_futex(bool fshared); diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index cfc8001e88ea..36824b64219a 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-or-later -#include #include #include @@ -85,15 +84,12 @@ SYSCALL_DEFINE3(get_robust_list, int, pid, long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, u32 __user *uaddr2, u32 val2, u32 val3) { + unsigned int flags = futex_to_flags(op); int cmd = op & FUTEX_CMD_MASK; - unsigned int flags = 0; - if (!(op & FUTEX_PRIVATE_FLAG)) - flags |= FLAGS_SHARED; - - if (op & FUTEX_CLOCK_REALTIME) { - flags |= FLAGS_CLOCKRT; - if (cmd != FUTEX_WAIT_BITSET && cmd != FUTEX_WAIT_REQUEUE_PI && + if (flags & FLAGS_CLOCKRT) { + if (cmd != FUTEX_WAIT_BITSET && + cmd != FUTEX_WAIT_REQUEUE_PI && cmd != FUTEX_LOCK_PI2) return -ENOSYS; } @@ -201,21 +197,19 @@ static int futex_parse_waitv(struct futex_vector *futexv, unsigned int i; for (i = 0; i < nr_futexes; i++) { + unsigned int flags; + if (copy_from_user(&aux, &uwaitv[i], sizeof(aux))) return -EFAULT; if ((aux.flags & ~FUTEX2_MASK) || aux.__reserved) return -EINVAL; - if (!IS_ENABLED(CONFIG_64BIT) || in_compat_syscall()) { - if ((aux.flags & FUTEX2_64) == FUTEX2_64) - return -EINVAL; - } - - if ((aux.flags & FUTEX2_64) != FUTEX2_32) + flags = futex2_to_flags(aux.flags); + if (!futex_flags_valid(flags)) return -EINVAL; - futexv[i].w.flags = aux.flags; + futexv[i].w.flags = flags; futexv[i].w.val = aux.val; futexv[i].w.uaddr = aux.uaddr; futexv[i].q = futex_q_init; diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c index ba01b9408203..fa9757766103 100644 --- a/kernel/futex/waitwake.c +++ b/kernel/futex/waitwake.c @@ -419,11 +419,11 @@ static int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *wo */ retry: for (i = 0; i < count; i++) { - if ((vs[i].w.flags & FUTEX_PRIVATE_FLAG) && retry) + if (!(vs[i].w.flags & FLAGS_SHARED) && retry) continue; ret = get_futex_key(u64_to_user_ptr(vs[i].w.uaddr), - !(vs[i].w.flags & FUTEX_PRIVATE_FLAG), + vs[i].w.flags & FLAGS_SHARED, &vs[i].q.key, FUTEX_READ); if (unlikely(ret))