From patchwork Sun Nov 3 17:03:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= X-Patchwork-Id: 13860527 Received: from todd.t-8ch.de (todd.t-8ch.de [159.69.126.157]) (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 5505218BC05; Sun, 3 Nov 2024 17:04:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.69.126.157 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730653486; cv=none; b=Zz+WPkP96qVS3AaJZPnF+1gB8qjmO6WM+tdgsF6geIOZxT0H8LF4FMEZT90nNVH5S1XptV0r1MC9mjA5FNhxcjd4Q/3Nioh2M9meX+FwXnQ/IBpG6jtq00h5dmEmicKD0/OWwDlFkRxz+WfhRvpssT46d0rUadlh4YYwnJ9nww4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730653486; c=relaxed/simple; bh=vzqsMVfnVQ7g+xXQgYvHKh8WFOGMi08tymfd1lvAle8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=tVs+qYp/nmA3OGaq9vd0mrAFPhuj89u6vrpQYzqzg2+S1z/OMLfW+z17ddvn/kTQkWGQXKtM46DZtnHZbRQAqo6Utl9bGOghgXDUGjzk/VLTXZJBe3vFXBXNpMsMaXN6H63WUy+B3sM4fxw61dHROMUCgNEvdqBmjL3nYKqaj38= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=weissschuh.net; spf=pass smtp.mailfrom=weissschuh.net; dkim=pass (1024-bit key) header.d=weissschuh.net header.i=@weissschuh.net header.b=je9uI76l; arc=none smtp.client-ip=159.69.126.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=weissschuh.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=weissschuh.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=weissschuh.net header.i=@weissschuh.net header.b="je9uI76l" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=weissschuh.net; s=mail; t=1730653482; bh=vzqsMVfnVQ7g+xXQgYvHKh8WFOGMi08tymfd1lvAle8=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=je9uI76lLR4y9OXxsJTuqI38lHi8HkhGJIFV6ZCs4146zr8UDcocsdPRPe5LeFYf8 /nzEaxpdd3g714OGoLTEVmDBSxSym4/0fJdP/ILanUgGd1lsKi+YxvHlrL3KGnTUxy 25OKvRhJ/iyvI2r1fL0kAV2rjeU/P1lDltJe/xCQ= From: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= Date: Sun, 03 Nov 2024 17:03:31 +0000 Subject: [PATCH v2 02/10] sysfs: introduce callback attribute_group::bin_size Precedence: bulk X-Mailing-List: platform-driver-x86@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241103-sysfs-const-bin_attr-v2-2-71110628844c@weissschuh.net> References: <20241103-sysfs-const-bin_attr-v2-0-71110628844c@weissschuh.net> In-Reply-To: <20241103-sysfs-const-bin_attr-v2-0-71110628844c@weissschuh.net> To: Greg Kroah-Hartman , "Rafael J. Wysocki" , Bjorn Helgaas , Srinivas Kandagatla , Davidlohr Bueso , Jonathan Cameron , Dave Jiang , Alison Schofield , Vishal Verma , Ira Weiny , Alex Deucher , =?utf-8?q?Christian_K=C3=B6nig?= , Xinhui Pan , David Airlie , Simona Vetter , Dennis Dalessandro , Jason Gunthorpe , Leon Romanovsky , Tudor Ambarus , Pratyush Yadav , Michael Walle , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Naveen Krishna Chatradhi , Carlos Bilbao , Hans de Goede , =?utf-8?q?Ilpo_J=C3=A4rvinen?= , "David E. Box" , "James E.J. Bottomley" , "Martin K. Petersen" , Richard Henderson , Matt Turner , Frederic Barrat , Andrew Donnellan , Arnd Bergmann , Logan Gunthorpe , "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui Cc: Dan Williams , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-cxl@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, linux-mtd@lists.infradead.org, platform-driver-x86@vger.kernel.org, linux-scsi@vger.kernel.org, linux-usb@vger.kernel.org, linux-alpha@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-hyperv@vger.kernel.org, =?utf-8?q?Tho?= =?utf-8?q?mas_Wei=C3=9Fschuh?= X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1730653468; l=2296; i=linux@weissschuh.net; s=20221212; h=from:subject:message-id; bh=vzqsMVfnVQ7g+xXQgYvHKh8WFOGMi08tymfd1lvAle8=; b=+c8c3AK6YNFtR/f5MlFDxfac5E4AdcTfe/LYH8cKiLv+aN2C4MrR8vpsa2SsTXy5NHtfEpdBh t4Y6vgc31e8BINAGXwLU2VEDayYxRmKzGs5LRvtEfi4Ux875Z1qlOu8 X-Developer-Key: i=linux@weissschuh.net; a=ed25519; pk=KcycQgFPX2wGR5azS7RhpBqedglOZVgRPfdFSPB1LNw= Several drivers need to dynamically calculate the size of an binary attribute. Currently this is done by assigning attr->size from the is_bin_visible() callback. This has drawbacks: * It is not documented. * A single attribute can be instantiated multiple times, overwriting the shared size field. * It prevents the structure to be moved to read-only memory. Introduce a new dedicated callback to calculate the size of the attribute. Signed-off-by: Thomas Weißschuh --- fs/sysfs/group.c | 2 ++ include/linux/sysfs.h | 8 ++++++++ 2 files changed, 10 insertions(+) diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c index 45b2e92941da1f49dcc71af3781317c61480c956..8b01a7eda5fb3239e138372417d01967c7a3f122 100644 --- a/fs/sysfs/group.c +++ b/fs/sysfs/group.c @@ -98,6 +98,8 @@ static int create_files(struct kernfs_node *parent, struct kobject *kobj, if (!mode) continue; } + if (grp->bin_size) + size = grp->bin_size(kobj, *bin_attr, i); WARN(mode & ~(SYSFS_PREALLOC | 0664), "Attribute %s: Invalid permissions 0%o\n", diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index c4e64dc112063f7cb89bf66059d0338716089e87..4746cccb95898b24df6f53de9421ea7649b5568f 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -87,6 +87,11 @@ do { \ * SYSFS_GROUP_VISIBLE() when assigning this callback to * specify separate _group_visible() and _attr_visible() * handlers. + * @bin_size: + * Optional: Function to return the size of a binary attribute + * of the group. Will be called repeatedly for each binary + * attribute in the group. Overwrites the size field embedded + * inside the attribute itself. * @attrs: Pointer to NULL terminated list of attributes. * @bin_attrs: Pointer to NULL terminated list of binary attributes. * Either attrs or bin_attrs or both must be provided. @@ -97,6 +102,9 @@ struct attribute_group { struct attribute *, int); umode_t (*is_bin_visible)(struct kobject *, struct bin_attribute *, int); + size_t (*bin_size)(struct kobject *, + const struct bin_attribute *, + int); struct attribute **attrs; struct bin_attribute **bin_attrs; };