From patchwork Thu Jul 20 22:18:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13321128 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 A8841C001DF for ; Thu, 20 Jul 2023 22:19:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229727AbjGTWTN (ORCPT ); Thu, 20 Jul 2023 18:19:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46550 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229579AbjGTWTM (ORCPT ); Thu, 20 Jul 2023 18:19:12 -0400 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 213C5110 for ; Thu, 20 Jul 2023 15:19:12 -0700 (PDT) Received: by mail-pf1-x42c.google.com with SMTP id d2e1a72fcca58-682a5465e9eso264736b3a.1 for ; Thu, 20 Jul 2023 15:19:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20221208.gappssmtp.com; s=20221208; t=1689891551; x=1690496351; 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=42VaD870OeDvxzIrHEo8+GOUntGBOgUhMszqKfQUcYA=; b=aRp2lyGJ9rCt8dC0Zs9t7I6/p/fey50e1NP4ZRNKHfd7HYSRv7PedoR4ShT2zbBLHF HgXnL1Q0MyE4L5xI6izlKFnypZThHMdOZUBw8g+8q/z4GKvqUP2Bc+ETo8L/mmnuGPCA NOyuA7NMBtD9hPDx8k+aGTerFKPerF0nDG9tnyaJeY3xxJl8rWyZHdePIXirLQdCSfb7 IGkyla4MxeaihKNq19CPpXMhMAFTBuYhSVdO39tTJKw4tt1CSoWCJKi1QsNoZfv+0PaH E6EXS6iS/5tw0sJ5N3ZIS49DR/yfjO2BHA3bBJ6+jcAfnptBLh95h0WnBXNR1I8R7ONy kkMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689891551; x=1690496351; 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=42VaD870OeDvxzIrHEo8+GOUntGBOgUhMszqKfQUcYA=; b=DHORJBtepj4upjttOvdWInin2I0pbxK8gJUYYUooAxGHLS9Sv2HW29EEgBon67uF7T PFmTrO1pl4Yz5mSoqqo3WheA6sbdoiXjeZc1R3sfthFKGKCMiPQKFW6GtzRGqHb6CM+N xiOfSLuehdAeDoIrTXOm7Kzb4WKpyhZjjq596828v+TrTVHhZyws8HGhe8+Tw7tvnmLG fx2RgovMb5Z/uBkRYyWabjOn+3tTYBaFwie2TK0LJnNK1hmWuXJmfwqLKukDiD9HOUC7 LpbZMKExExWk0p7wlvan8Raf9tLBlCyCL4PWfa/WYMT6IV4wWuLNuCtawPFLU5D/+tQa +NvQ== X-Gm-Message-State: ABy/qLY4a2MR3PCvr3YiIlM3TaHXCUxR5a3bFFKiyhBz2+8IZOIBs5D4 xE9qdgw3M6QxawCm7i3rQaPvihvu0Ww/8bEeoOQ= X-Google-Smtp-Source: APBJJlGQbbA44tc8PP7+BeAbRXR4aaPtZk5MRld32V9dcrd1UaPCyDgN6xO+L62ThkCbhvkZCTnNXA== X-Received: by 2002:a05:6a20:42a8:b0:123:3ec2:360d with SMTP id o40-20020a056a2042a800b001233ec2360dmr205014pzj.5.1689891550897; Thu, 20 Jul 2023 15:19:10 -0700 (PDT) Received: from localhost.localdomain ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id q1-20020a63bc01000000b0055b3af821d5sm1762454pge.25.2023.07.20.15.19.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 20 Jul 2023 15:19:09 -0700 (PDT) From: Jens Axboe To: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org Cc: peterz@infradead.org, andres@anarazel.de, Jens Axboe Subject: [PATCH 03/10] futex: Flag conversion Date: Thu, 20 Jul 2023 16:18:51 -0600 Message-Id: <20230720221858.135240-4-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230720221858.135240-1-axboe@kernel.dk> References: <20230720221858.135240-1-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 | 48 ++++++++++++++++++++++++++++++++++++++--- kernel/futex/syscalls.c | 21 +++++++++++------- kernel/futex/waitwake.c | 4 ++-- 3 files changed, 60 insertions(+), 13 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index b5379c0e6d6d..54f4470b7db8 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -16,8 +16,15 @@ * 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 +32,43 @@ */ # 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 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 d5bb6dad22fe..7234538a490d 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -85,15 +85,12 @@ 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; } @@ -201,6 +198,8 @@ static int futex_parse_waitv(struct futex_vector *futexv, unsigned int i; for (i = 0; i < nr_futexes; i++) { + unsigned int bits, flags; + if (copy_from_user(&aux, &uwaitv[i], sizeof(aux))) return -EFAULT; @@ -210,7 +209,13 @@ static int futex_parse_waitv(struct futex_vector *futexv, if ((aux.flags & FUTEX2_64) != FUTEX2_32) return -EINVAL; - futexv[i].w.flags = aux.flags; + flags = futex2_to_flags(aux.flags); + bits = 8 * futex_size(flags); + + if (bits < 64 && aux.val >> bits) + return -EINVAL; + + 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))