From patchwork Wed Sep 11 20:29:40 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13801064 Received: from mail-io1-f52.google.com (mail-io1-f52.google.com [209.85.166.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0A7DB14386D for ; Wed, 11 Sep 2024 20:30:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.52 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726086630; cv=none; b=kEzv9HT9NDgz/XIvc4Bv+9SlIMZnTVdgPnfiUznDRsfTCZjMpfG696F3H8Hj0YumqMW/OqPKlixxwney9H4mUoBE+LG8yAcpv0lYr1o2L7t/TxqxtXz725ePOmmxDAb+Sa8fzbgXL/ttoUPrJ57JIaZZk0xzTJkCi6qZn3nt/V4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726086630; c=relaxed/simple; bh=GM5rez7i8AcYityEiDjC4PZI1ccMmlLlITNVJtUHxTM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QgigX1msdEsW5fTIA/rrJN2iG+EdJbphVRiUf0MMkXE3S2dFAItE3WzGV+M/AkCqZDx4CHft8/I02E7HILRPMYsD7CThIlJgpGl4S/G23Og6mYczNNMiSkO9wzT7P8oKhyW46Pu4ibS0Zts0TLylyLn+cxs1tAKgovnmQppuzn0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk; spf=pass smtp.mailfrom=kernel.dk; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b=PgW6H4/q; arc=none smtp.client-ip=209.85.166.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kernel.dk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20230601.gappssmtp.com header.i=@kernel-dk.20230601.gappssmtp.com header.b="PgW6H4/q" Received: by mail-io1-f52.google.com with SMTP id ca18e2360f4ac-829f7911eecso9070339f.1 for ; Wed, 11 Sep 2024 13:30:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1726086626; x=1726691426; darn=vger.kernel.org; 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=pbZg1ed04SkE9PDBN3N3iel9ESiPexbtZx/Ls3JLSeo=; b=PgW6H4/qfR+fa9xRZpxB10Iqm1WYklhlFnH1/QJsvq8qFc1eefkO5dxv4Cn4Q5I9UB BOogPXJRwg3rR2CEAPcIVQdiTNj8ZOyz6PePDkHF5RAeF5DqPXuoG7cmczdn4vdsJDU6 4/wKzg0HLntMBossAa8pkmDP9xpK72ROkgsdmnDnvwZ/zqpqg7/GuLMnN0hNPCSUn8VU AmH2PvE5a0lXdTyX/mWy4bbTla5ncaFUFHvPrIqaceQfNreNiRmmnvBsKiusPXob5X01 50L3IKPyss14T11WR+K4oTxDnkQxKfmvx1+am6miNpoQiRR6NirNd9WsfVdccEBXCSI9 LAOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726086626; x=1726691426; 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=pbZg1ed04SkE9PDBN3N3iel9ESiPexbtZx/Ls3JLSeo=; b=tIdaoK2sFGviMIcFpJx8I/wBmChIeZi3i2HiUOP4JAnb6jriDGdXz8yWMfm25+CDwJ ZR+q1r3MIk6IGjUn/8IaI5W+wNv8qcfbdolX6Ot+LfqsOweSnPo94GrdEkEW2InoURh6 pndFTnacrCFGK9kS8GgS4Ck/ogPA1nPQvejW/yyigcDnVy1e1k5xFxO8gy7Ww6KhnK4f 9lt1AxSL0w84+8g7J0ZIX+4qug/9ngVhTvvx3Ci1Yh2skkiY0PQXo4layHuw9RH5DT16 r/aGOxKSfq2bUV/VxNm2Ml0CEIb6Cop5kR9bvHl4mbqSkITNtoLq/UoFA/Pv55KAaFUb xwHQ== X-Gm-Message-State: AOJu0YyhIvuZsw0TzWMutaoMZ6rJYxG9HDF/FJWXi717kGNnS2fS7OhF Gfg0HL/FSi6eft7IUWqDO047mnAePpyC5b5xeVgE6S/24vQMVu4/HnLtppNEYMOS0ljX9SWUIA+ BLRI= X-Google-Smtp-Source: AGHT+IE8QSi7rRuxJXP5MFAxMTfbnQXLmVdlh+6QaifvAXACmGm3dL5U8hEkzzPEc/nh4bKy5p5qtw== X-Received: by 2002:a05:6e02:1a88:b0:3a0:80c6:367 with SMTP id e9e14a558f8ab-3a084931e1emr4426075ab.19.1726086626610; Wed, 11 Sep 2024 13:30:26 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id 8926c6da1cb9f-4d35f433d60sm185173173.26.2024.09.11.13.30.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Sep 2024 13:30:25 -0700 (PDT) From: Jens Axboe To: io-uring@vger.kernel.org Cc: Jens Axboe Subject: [PATCH 2/3] io_uring/rsrc: add reference count to struct io_mapped_ubuf Date: Wed, 11 Sep 2024 14:29:40 -0600 Message-ID: <20240911203021.416244-3-axboe@kernel.dk> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240911203021.416244-1-axboe@kernel.dk> References: <20240911203021.416244-1-axboe@kernel.dk> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Currently there's a single ring owner of a mapped buffer, and hence the reference count will always be 1 when it's torn down and freed. However, in preparation for being able to link io_mapped_ubuf to different spots, add a reference count to manage the lifetime of it. Signed-off-by: Jens Axboe --- io_uring/rsrc.c | 3 +++ io_uring/rsrc.h | 1 + 2 files changed, 4 insertions(+) diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index d42114845fac..28f98de3c304 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -116,6 +116,8 @@ static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slo *slot = NULL; if (imu != &dummy_ubuf) { + if (!refcount_dec_and_test(&imu->refs)) + return; for (i = 0; i < imu->nr_bvecs; i++) unpin_user_page(imu->bvec[i].bv_page); if (imu->acct_pages) @@ -990,6 +992,7 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, imu->folio_shift = data.folio_shift; imu->folio_mask = ~((1UL << data.folio_shift) - 1); } + refcount_set(&imu->refs, 1); off = (unsigned long) iov->iov_base & ~imu->folio_mask; *pimu = imu; ret = 0; diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h index 3d0dda3556e6..98a253172c27 100644 --- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -47,6 +47,7 @@ struct io_mapped_ubuf { unsigned int folio_shift; unsigned long acct_pages; unsigned long folio_mask; + refcount_t refs; struct bio_vec bvec[] __counted_by(nr_bvecs); };