From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 45C6115539A; Fri, 8 May 2026 04:37:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778215036; cv=none; b=JtOvs1GvypVCCDWrHNsXu7Vz+eivuWuV0IFgFnc2ojf0rgjwREQr+VjWG4l+Unt0RaE742X0W0k9TVTkDFk8DgRlh/LGm3u79fBYw0mnC9Tj/5wHUe/kOcCOF/WNJ5tt4kHVNbrIW6c1PvHc7M4JfHbOeKX44QLpoFsno4Um1pM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778215036; c=relaxed/simple; bh=g1Q0Y9xFxmkBFDILfcdAU3XRw5NhqOHXxvlpf+w+W4s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Yflkpni5iTNoZuYAVY1bZvfiQIOugokzHcDgUpU2zYDST6xnPiXCN3iSy7rsi+Kw5nOFylSX27THex8waBSIkaj8gyNoEFemufWWfb81IvSp5+QRjGaKZo6spq73fY0/QfSWWmttki2u74T3yvci55J6+CuH/YYPx05Y2uz8h4A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pDIZz6JT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pDIZz6JT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7B32C2BCB0; Fri, 8 May 2026 04:37:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778215036; bh=g1Q0Y9xFxmkBFDILfcdAU3XRw5NhqOHXxvlpf+w+W4s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pDIZz6JT+F50/NoXuF7lFmNqg8Xpq6ar8JHkiL1odWO86N+rOe8JidqrT7wtsIW3t 93FSlxaBsR1QokyyJQgywFCxNoHnJN1NdlhT9+bOWnTetGZ0UGfNr2EJYfRxtSa9+7 QafCJBekO6SkU2yTq/Ljkct+pzdCfy1y6YRu75s/pcMlmDhnqoynyxXB9EWN3hAlq+ ShPRwGhnWD94gNzGH+PKAm0G7/pWojPkWZV7fdHaAbDN0ZvvmcR/LehdvcM5/RxpQY fy+35MGYw1z1BM427XCnE9GzPrIrGwKKUJDZMlUpUYQFHur1LncvYHjphNqfo8qNUB zzg9mYwpDD3dw== From: =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= To: Bjorn Helgaas Cc: Bjorn Helgaas , Manivannan Sadhasivam , Lorenzo Pieralisi , Alex Williamson , Magnus Lindholm , Matt Turner , Richard Henderson , Christophe Leroy , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Dexuan Cui , =?UTF-8?q?Krzysztof=20Ha=C5=82asa?= , Lukas Wunner , "Oliver O'Halloran" , Saurabh Singh Sengar , Shuan He , Srivatsa Bhat , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , linux-pci@vger.kernel.org, linux-alpha@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: [PATCH v7 24/24] PCI/sysfs: Limit BAR resize attribute scope to platforms with PCI mmap Date: Fri, 8 May 2026 04:35:43 +0000 Message-ID: <20260508043543.217179-25-kwilczynski@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260508043543.217179-1-kwilczynski@kernel.org> References: <20260508043543.217179-1-kwilczynski@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, __resource_resize_store() uses sysfs_remove_groups() and sysfs_create_groups() on pci_dev_resource_attr_groups to tear down and recreate the resourceN files after a BAR resize, so the updated BAR sizes are visible in sysfs. The resourceN files only exist on platforms that define HAVE_PCI_MMAP or ARCH_GENERIC_PCI_MMAP_RESOURCE. On platforms that define neither, pci_dev_resource_attr_groups is NULL and the sysfs_remove_groups() and sysfs_create_groups() calls in __resource_resize_store() become no-ops. Resizable BAR (ReBAR) is a PCI Express extended capability (PCI_EXT_CAP_ID_REBAR) that requires PCIe extended config space. Every PCIe-capable architecture defines HAVE_PCI_MMAP or ARCH_GENERIC_PCI_MMAP_RESOURCE (via arch headers or the asm-generic/pci.h fallback). Architectures without either only support conventional PCI and cannot have any ReBAR-capable devices. Thus, move the resize show and store helpers, the per-BAR attribute definitions, and the attribute group behind the existing #ifdef HAVE_PCI_MMAP || ARCH_GENERIC_PCI_MMAP_RESOURCE guard, and fold the group reference in pci_dev_groups[] into the existing #if block. Tested-by: Shivaprasad G Bhat Signed-off-by: Krzysztof Wilczyński --- drivers/pci/pci-sysfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index f5427bcfb0cc..6099371f67e7 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1661,6 +1661,7 @@ static const struct attribute_group pci_dev_reset_method_attr_group = { .is_visible = pci_dev_reset_attr_is_visible, }; +#if defined(HAVE_PCI_MMAP) || defined(ARCH_GENERIC_PCI_MMAP_RESOURCE) static ssize_t __resource_resize_show(struct device *dev, int n, char *buf) { struct pci_dev *pdev = to_pci_dev(dev); @@ -1775,6 +1776,7 @@ static const struct attribute_group pci_dev_resource_resize_attr_group = { .attrs = resource_resize_attrs, .is_visible = resource_resize_attr_is_visible, }; +#endif static struct attribute *pci_dev_dev_attrs[] = { &dev_attr_boot_vga.attr, @@ -1849,8 +1851,8 @@ const struct attribute_group *pci_dev_groups[] = { &pci_dev_resource_io_attr_group, &pci_dev_resource_uc_attr_group, &pci_dev_resource_wc_attr_group, -#endif &pci_dev_resource_resize_attr_group, +#endif &pci_dev_config_attr_group, &pci_dev_rom_attr_group, &pci_dev_reset_attr_group, -- 2.54.0