From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F087B4477FA; Mon, 7 Sep 2026 10:23:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788776634; cv=none; b=hF/mUp3ihyecsTrrSOmx+xQGSRNheh5USY8C33iMfcQRqll+fXzcQvx5zPsyQtrTQShQPIACagff/+3z5tSAN32/WmUwPf3XMb/eE4OqphyXN7aE576wScesA6oLYNapYhluut61uEfhQIoLgEVvBRg0EWWRLoFeht8uAiaTO4w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788776634; c=relaxed/simple; bh=qFJbJp9Uv4c+AIOE27dclvuDeZ9IhDKG4rxK4P7RsjE=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=Qv6TUVWsea2KAu+wuM10Gdb/bbtdHM5loSyO1aIA/aptMnyI0F8wxxHq9NVVswU+qQvdd+unN7pu277p0qgphq63U9T2VY4yD9tXRUhjc9Br3W5+ztI76Xh5aMp7XWFnbNsAcyUPZOeMEBHm2qaliPCDSDOETqU+19qRtAHza8Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=W3K/wLkW; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="W3K/wLkW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA8631F00A3E; Mon, 7 Sep 2026 10:23:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788776632; bh=QBl4EA0xu6TPR7bo/qzVGPSEuODGi+VrBZaLJjj3jl8=; h=From:Subject:Date:To:Cc; b=W3K/wLkWX6CuLvlwKhn0U4ZI+2bfSag8owmRUSS2l3C9lstfTM1Sfn0T2ncJCgU6J S0EkLOlgCjZQBUiu3f+Lek67z0vBdvPdze/Xni/fOUSI72mlaW1NQyiuPg2/qJocav EWWl6qkc01U3JcOk8fowht2ZHXeZSgXZEmqoXYfGtTui6FIs8Zwcs8DFh8sdgHo+It 1Wo9Q3wbcU99rGLPdrWqL/9QEx0FqTuk6yNTKuFuoEBW7Q7zq9ubdPnDdxVmutDYBT i3COGAB7YhhUwquaROAmQWRS3C0/o0Rtf+EAFOE17+/s0ogpHf72iK2IXEysqtlQeS wrvNlk1e3LGkQ== From: "Mike Rapoport (Microsoft)" Subject: [PATCH 00/13] s390/cio: replace page allocator calls with k[mz]alloc() Date: Mon, 07 Sep 2026 13:23:41 +0300 Message-Id: <20260907-s390-cio-ready-v1-0-ca7f39806234@kernel.org> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-B4-Tracking: v=1; b=H4sIAAAAAAAC/yXMSw7CMAwE0KtUXmOUD2paroJYJKlDwyJFNiBQ1 buTlOUbzcwKQpxJ4NytwPTOkpdSoQ8dxNmXG2GeqsEo06tRORQ7Kox5QSY/fVEP5GxKQ38yCer owZTyZz+8XP+WV7hTfLaX1gheCAP7EucW7XRHixw1bNsP2whiIZEAAAA= X-Change-ID: 20260907-s390-cio-ready-18e73ff8642f To: Heiko Carstens , Vasily Gorbik , Alexander Gordeev Cc: Christian Borntraeger , Mike Rapoport , Peter Oberparleiter , Sven Schnelle , Vineeth Vijayan , Vlastimil Babka , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org X-Mailer: b4 0.17-dev The saga continues :) This series covers CIO, QDIO, SCM and IDAL buffer allocations. This is a (small) part of larger work of replacing page allocator calls with kmalloc. My initial intention a few month ago was to remove ugly casts [1], but then willy pointed out that Linus objected to something like this [2] and it looks like more than a decade old technical debt. Largely, anything that doesn't need struct page (or a memdesc in the future) should just use kmalloc() or kvmalloc() to allocate memory. kmalloc() guarantees alignment, physical contiguity and working virt_to_phys() and beside nicer API that returns void * on alloc and doesn't require to know the allocation size on free, kmalloc() provides better debugging capabilities than page allocator. Another thing is that touching these allocation sites gives the reviewers opportunity to see if a PAGE_SIZE buffer is actually needed or maybe another size is appropriate. For larger allocations that don't need physically contiguous memory kvmalloc() can be a better option that __get_free_pages() because under memory pressure it's is easier to allocate several order-0 pages than a physically contiguous chunk with the same number of pages. And last, but not least, removing needless calls to page allocator should help with memdesc (aka project folio) conversion. There will be way less places to audit to see if the user was actually using struct page. The patches are grouped by buffer usage and ordered by file or subsystem. Related CHSC work areas and requests are kept together. While on it, use __free(kfree) for the SCM information buffer and local buffers in synchronous CHSC ioctl handlers. The CHSC cleanup is kept in a separate patch. Also in git: https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git gfp-to-kmalloc/s390-cio [1] https://lore.kernel.org/all/20251018093002.3660549-1-rppt@kernel.org/ [2] https://lore.kernel.org/all/CA+55aFwp4iy4rtX2gE2WjBGFL=NxMVnoFeHqYa2j1dYOMMGqxg@mail.gmail.com/ --- Mike Rapoport (Microsoft) (13): s390/chsc: Use kzalloc() for CUBs s390/chsc: Use kzalloc() for the SEI work area s390/chsc_sch: Use kzalloc() for CHSC requests s390/chsc_sch: Use __free(kfree) for synchronous CHSC requests s390/cio: Use kzalloc() for CHSC work areas s390/cmf: Use kmalloc() for the CMB area s390/idals: Use kmalloc() for IDAL data buffers s390/qdio_main: Use kzalloc() for the IRQ structure s390/qdio_main: Use kzalloc() for the QDR s390/qdio_setup: Use kzalloc() for QDIO buffers s390/qdio_setup: Use kzalloc() for the storage list s390/qdio_setup: Use kzalloc() for the SSQD request s390/scm: Use kmalloc() for SCM information arch/s390/include/asm/idals.h | 6 +- drivers/s390/cio/chsc.c | 20 +-- drivers/s390/cio/chsc_sch.c | 300 ++++++++++++++-------------------------- drivers/s390/cio/cmf.c | 8 +- drivers/s390/cio/qdio.h | 2 +- drivers/s390/cio/qdio_main.c | 19 +-- drivers/s390/cio/qdio_setup.c | 14 +- drivers/s390/cio/qdio_thinint.c | 2 +- drivers/s390/cio/scm.c | 7 +- 9 files changed, 144 insertions(+), 234 deletions(-) --- base-commit: cee9395acd8043be0644b25c34bfa86623f2b935 change-id: 20260907-s390-cio-ready-18e73ff8642f -- Sincerely yours, Mike.