From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f51.google.com (mail-io1-f51.google.com [209.85.166.51]) (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 D19721B6520 for ; Wed, 11 Sep 2024 20:07:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.51 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726085237; cv=none; b=quxbURpT4ZuLR1J/Clv4GzBWLFBU2WbfacNiICiGkMWhZH8w2oZofOuh+r+xieHdhyQXGnKH5TUlqsAPymUV8kpbCOWLVsaUIETBlyAOVsQ3Ypvumqgkgd5pXr7sEpuGk4dlB0O/pCr8OiI2tHEBkgbjk69/eERr/1hfi7nWSqA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726085237; c=relaxed/simple; bh=GM5rez7i8AcYityEiDjC4PZI1ccMmlLlITNVJtUHxTM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aBvHn5xM/5sa5WFFdhxY9+BASlAp1T9vLXbQEQzOn1zUaB8n3FdW/MLazSxMjj9zqA9zwePu60IiOn24Gk0aE5uSOixo3bxhsdHs1V1g3ihLmCJjhYsmX9VoR5vrGusHKlY7tpMrYIrEwT/asy+aw/LArywXFqC/9j2FX8TqB3c= 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=vKyIsyx3; arc=none smtp.client-ip=209.85.166.51 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="vKyIsyx3" Received: by mail-io1-f51.google.com with SMTP id ca18e2360f4ac-82cd869453eso9070739f.0 for ; Wed, 11 Sep 2024 13:07:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20230601.gappssmtp.com; s=20230601; t=1726085233; x=1726690033; 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=vKyIsyx3i8UHOK7MTPFJ/QnN1Iewad1PhoysqdyFdx416vttKmEs2y1kYrcH56Ecfk rFs/YLeGOtec+uwrlwqv8maGdXOV993NcZrCxawtEY9f5GEhYPJFRgo6MC1AXpdsXSUF VCsYpuGt3p8lpVqUme3HsYMj3+fa75ld89nON6ylCwH1wOkVrkJ44LtK85WjRlhJKMtd lKVKRQFgUCAUWJ0KMRXVtQiGq/ja8xs3sscQnt4FCxcSCQkBLrxw43N19Lf6qijRGkpU 87lIdEgoS0bEkLkYUWy/WB4tOo3vXL4QEFdLUnOYTcTD5ozZ3F5nNr14qo7gWJKNDwpg l9ng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1726085233; x=1726690033; 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=w3kFzHVYXgtRqYMLf3j/eFZ26nuZF6Jk6bvQOxuZAw+BdcH1U6euCZlvss4/yb/kAT lGmEW/oRitQnHqbfht3Y6YDQ26sLvaoqPN2jfOKen1bmZ5xgN/WNIAx973elxf8SRrGm cj1rC33/BDOZXz+eBnlgkXm97+stEztxiOI6ImkrHRAczwI9Kp/bv113Pgsn4MtaEicd KOAPvfYSSPyaxbb+stmWoBx8RWRaS3Gp1eg2zvSfAt2h+9Ql0Gc3RTEiaHfRigHyDXAQ fc4m/rVxsD6VMf6KDJfr5dMkN1nRQUZV25JdTiW2QyKDTSe9Wsr4bNu+7Pda/ehWHv7Y /GxA== X-Gm-Message-State: AOJu0YwyxAS42KeTQ4K+jDppHF1gRacWCsq1jlgq1jINazTD8Iq2LJTX g30NbM69MKmyXejQrKREHwNhwHdGjL9xd6NQMFqnbFaFQZYw4PdbD8pNzwbjJlTGFYdhvdFWQsr cO0U= X-Google-Smtp-Source: AGHT+IGBYqW2ZAz0z/30zJzJ6WIo1Ls3V4PGZj322ssfjujSLuo+ksg/iQXsomqCQP5GhKmUdnwD8w== X-Received: by 2002:a05:6602:6d13:b0:82c:f30d:fc72 with SMTP id ca18e2360f4ac-82d1f8b72dfmr118386039f.2.1726085233383; Wed, 11 Sep 2024 13:07:13 -0700 (PDT) Received: from localhost.localdomain ([96.43.243.2]) by smtp.gmail.com with ESMTPSA id ca18e2360f4ac-82aa733a1d6sm289860239f.1.2024.09.11.13.07.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Sep 2024 13:07:12 -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 14:03:53 -0600 Message-ID: <20240911200705.392343-3-axboe@kernel.dk> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240911200705.392343-1-axboe@kernel.dk> References: <20240911200705.392343-1-axboe@kernel.dk> Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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); }; -- 2.45.2