From nobody Mon Feb 9 06:33:56 2026 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (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 C69FF3A0E9A for ; Wed, 4 Feb 2026 20:10:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770235837; cv=none; b=eB9St+BHnjy9QtToEu6QkhMmU+U3i6RhyHK6qLyUnT6IfnazwOWm+LBIk+EwE3P/44Ufzg3sxQYA7FN9km0RxmPRSnObgrL+ZqfPQ7jaP1t6HihkYsElJpCZIJgzzqVxTbAE7P8ctv3rE0NLJvY5XDcmGHRir3kPWGm5g3VFEs8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770235837; c=relaxed/simple; bh=xeVIe8cmrntR0enuK392UB2SXROYBNmtYamPiBlWwyw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=DnXqk0zuj9IDrSAtdqxfdNjC9FtieQd4VrNmm+31osO/Cjz3rH9ntTFcPgqzx2c0VSpfT6f5OOwhw58jghtMm8mjqbjifTY78gdqaXECSt73ps+n7t1aVKReebzFFr29k8rtB8+A8HPthdS9AwKUOV3V+qz21LGCIFOryr7zwDE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=IR2U3YZ9; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="IR2U3YZ9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1770235360; bh=xeVIe8cmrntR0enuK392UB2SXROYBNmtYamPiBlWwyw=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=IR2U3YZ9XeUWH2ccVQaIHAil82kaplR8ZdUbQIp3gsKJHSJoihkRV+aBQphygD6r9 RXvrVP5R3+d0ayg2mWnrgtooW8OyAR9CZmoL+0HqtQU6IzdXEN8wyL1t4PWQj845JZ KZo4Fkt/3/hgWDf7cNxfu7hKwd29jCQumr4zSwA3tkMeZca8g764if0L3OJ1l3zGZM YAGx9C4L9DNZzqr5HJVRPopap5Ri/AbuMGqTnLenH53fnpVTsrsyYfv69gi/g+Mwo4 tgXOD/7jUzy35naUJAlOtTo9ysqbB3VTX7QlAYl94kNL/DZtzYf9hxX1K9tjP6dsdl SULP+VjTxB2Fg== Received: from localhost (unknown [82.79.138.145]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: cristicc) by bali.collaboradmins.com (Postfix) with ESMTPSA id CB79A17E13D3; Wed, 4 Feb 2026 21:02:40 +0100 (CET) From: Cristian Ciocaltea Date: Wed, 04 Feb 2026 22:02:28 +0200 Subject: [PATCH v7 1/4] uapi: Provide DIV_ROUND_CLOSEST() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260204-rk3588-bgcolor-v7-1-78d1d01c5ca1@collabora.com> References: <20260204-rk3588-bgcolor-v7-0-78d1d01c5ca1@collabora.com> In-Reply-To: <20260204-rk3588-bgcolor-v7-0-78d1d01c5ca1@collabora.com> To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan , Louis Chauvet , Haneen Mohammed , Melissa Wen , Jani Nikula , Andy Shevchenko Cc: Robert Mader , kernel@collabora.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, =?utf-8?q?N=C3=ADcolas_F=2E_R=2E_A=2E_Prado?= , Diederik de Haas , AngeloGioacchino Del Regno X-Mailer: b4 0.14.3 Currently DIV_ROUND_CLOSEST() is only available for the kernel via include/linux/math.h. Expose it to userland as well by adding __KERNEL_DIV_ROUND_CLOSEST() as a common definition in uapi. Additionally, ensure it allows building ISO C applications by switching from the 'typeof' GNU extension to the ISO-friendly __typeof__. Reviewed-by: N=C3=ADcolas F. R. A. Prado Tested-by: Diederik de Haas Acked-by: Andy Shevchenko Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: Cristian Ciocaltea --- include/linux/math.h | 18 +----------------- include/uapi/linux/const.h | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+), 17 deletions(-) diff --git a/include/linux/math.h b/include/linux/math.h index 6dc1d1d32fbc..1e8fb3efbc8c 100644 --- a/include/linux/math.h +++ b/include/linux/math.h @@ -89,23 +89,7 @@ } \ ) =20 -/* - * Divide positive or negative dividend by positive or negative divisor - * and round to closest integer. Result is undefined for negative - * divisors if the dividend variable type is unsigned and for negative - * dividends if the divisor variable type is unsigned. - */ -#define DIV_ROUND_CLOSEST(x, divisor)( \ -{ \ - typeof(x) __x =3D x; \ - typeof(divisor) __d =3D divisor; \ - (((typeof(x))-1) > 0 || \ - ((typeof(divisor))-1) > 0 || \ - (((__x) > 0) =3D=3D ((__d) > 0))) ? \ - (((__x) + ((__d) / 2)) / (__d)) : \ - (((__x) - ((__d) / 2)) / (__d)); \ -} \ -) +#define DIV_ROUND_CLOSEST __KERNEL_DIV_ROUND_CLOSEST /* * Same as above but for u64 dividends. divisor must be a 32-bit * number. diff --git a/include/uapi/linux/const.h b/include/uapi/linux/const.h index b8f629ef135f..565f309b9df8 100644 --- a/include/uapi/linux/const.h +++ b/include/uapi/linux/const.h @@ -50,4 +50,22 @@ =20 #define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) =20 +/* + * Divide positive or negative dividend by positive or negative divisor + * and round to closest integer. Result is undefined for negative + * divisors if the dividend variable type is unsigned and for negative + * dividends if the divisor variable type is unsigned. + */ +#define __KERNEL_DIV_ROUND_CLOSEST(x, divisor) \ +({ \ + __typeof__(x) __x =3D x; \ + __typeof__(divisor) __d =3D divisor; \ + \ + (((__typeof__(x))-1) > 0 || \ + ((__typeof__(divisor))-1) > 0 || \ + (((__x) > 0) =3D=3D ((__d) > 0))) ? \ + (((__x) + ((__d) / 2)) / (__d)) : \ + (((__x) - ((__d) / 2)) / (__d)); \ +}) + #endif /* _UAPI_LINUX_CONST_H */ --=20 2.52.0