From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 02ABBC5AD4E for ; Sun, 9 Aug 2026 19:24:33 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2692910E5A3; Sun, 9 Aug 2026 19:24:33 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.b="Fx8qZ+cH"; dkim-atps=neutral Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0B5D210E59D; Sun, 9 Aug 2026 19:24:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Cc:To:Message-Id:Content-Transfer-Encoding:Content-Type: MIME-Version:Subject:Date:From:From:Reply-To; bh=7lVGgG+rffgoqDRY53sS8WzYl0LZPOn29qL7x2dtp6Q=; b=Fx8qZ+cHMulseJFnqMgHnQlq2s yFu2cXLyvMXRlcoMm3whzoupoAGcvGMM8WSrFI27kQWLnZkppxGtZi/Q6LC9mF8Rwdq/lkU5bqh/K o0o321YB8u9XNg0y9xEZHOdpJrEBolI+MCYK8XEpItquSsKhtX7esxIjZ9pKf69HnHHnttXKYFiU6 00FV9gdn2KSFaNGm4ZH2ava43Os9vvrlRWGgHFzu7iT8YMXNr2ruOH+TXsFJRlhKH8v1lu32cUKW3 RG89SHDc+U+Oqoq8LYsthyhu5OWfodQ/X1w2SaM1qCljcSNwIi/mdV/+lab50rQnvuwn//PcKbbfY 31rPx3RQ==; Received: from [187.36.208.132] (helo=[10.0.0.1]) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1wt98G-00GH3T-ML; Sun, 09 Aug 2026 21:24:28 +0200 From: =?utf-8?q?Ma=C3=ADra_Canal?= Date: Sun, 09 Aug 2026 16:23:58 -0300 Subject: [PATCH 2/6] drm: Add drm_timeout_rel_to_jiffies() MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-Id: <20260809-drm-timeout-helpers-v1-2-2de67405a145@igalia.com> References: <20260809-drm-timeout-helpers-v1-0-2de67405a145@igalia.com> In-Reply-To: <20260809-drm-timeout-helpers-v1-0-2de67405a145@igalia.com> To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Alex Deucher , =?utf-8?q?Christian_K=C3=B6nig?= , Melissa Wen , Iago Toral , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Dave Stevenson , Raspberry Pi Kernel Maintenance Cc: kernel-dev@igalia.com, dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, =?utf-8?q?Ma=C3=ADra_Canal?= X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=2936; i=mcanal@igalia.com; h=from:subject:message-id; bh=5vPjp1FFMlftY4WwFNCfVKHzcupL9Mtq4xC5RoVutuE=; b=owEBbQGS/pANAwAKAT/zDop2iPqqAcsmYgBqeNPYMQi+XIRAdNwou33Fvqmhk58+ITxRJSaFb RpRQ7/OTISJATMEAAEKAB0WIQT45F19ARZ3Bymmd9E/8w6Kdoj6qgUCanjT2AAKCRA/8w6Kdoj6 qnAJCADZvCmEaJ82iRFSbe0xIFcsik9EKF+2HS0Jn8eMrnZhdae7Widjom8m4b9A21/QxJFdWyM kABajNzFyzqBNVX4ZTTrqppld3ND+pl26sj/Kc2b1Zl8r1dTwGyARiB89uOF6WDxROpoIGvyeku Uvjli2F5+hnARSCGA3NALeNlzg9Zecl1LPqIoGHdgGmNPSYF669+DC9nKjQswiJFuigSjvOvw69 7IypThiW/b0ZsyB7DDOATpyyyGW8fOerCbxlIGM6VdafcgAP1gzmopWYrN9YBgTFt9pH7odGEcA XKCmTYB+0p6BYbE8w6BFwspMA2LZDFznkX4b0csMYoPeRld4 X-Developer-Key: i=mcanal@igalia.com; a=openpgp; fpr=F8E45D7D0116770729A677D13FF30E8A7688FAAA X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" drm_timeout_abs_to_jiffies() covers the drivers whose wait UAPI takes an absolute deadline, but there is no equivalent for the drivers that express a wait as a duration. Drivers such as i915 and v3d convert the value themselves. Converting a nanosecond duration to jiffies needs some care. nsecs_to_jiffies() returns unsigned long, so on 32-bit a large userspace-supplied timeout overflows its range and is silently truncated. i915 already handles both cases in a local helper, which v3d has a copy of. Add the same conversion to the core, so that it is available to any driver and both copies can be dropped. Signed-off-by: Maíra Canal --- drivers/gpu/drm/drm_timeout.c | 29 +++++++++++++++++++++++++++++ include/drm/drm_utils.h | 1 + 2 files changed, 30 insertions(+) diff --git a/drivers/gpu/drm/drm_timeout.c b/drivers/gpu/drm/drm_timeout.c index 78e9f65e5477..30ad3e8ebc92 100644 --- a/drivers/gpu/drm/drm_timeout.c +++ b/drivers/gpu/drm/drm_timeout.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -45,3 +46,31 @@ signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec) return timeout_jiffies64 + 1; } EXPORT_SYMBOL(drm_timeout_abs_to_jiffies); + +/** + * drm_timeout_rel_to_jiffies - calculate jiffies timeout from relative value + * + * @timeout_nsec: relative timeout in ns, 0 for poll + * + * Calculate the timeout in jiffies from a relative timeout in ns, for drivers + * whose UAPI expresses a wait as a duration rather than as a deadline. + * + * The result is clamped to MAX_JIFFY_OFFSET. That keeps it positive once it is + * converted to the signed long taken by dma_fence_wait_timeout() and friends, + * which matters on 32-bit, and keeps it distinct from MAX_SCHEDULE_TIMEOUT so + * that a finite wait is never understood as an infinite one. + */ +unsigned long drm_timeout_rel_to_jiffies(u64 timeout_nsec) +{ + /* make 0 timeout means poll, as for the absolute variant */ + if (timeout_nsec == 0) + return 0; + + /* nsecs_to_jiffies64() does not guard against overflow */ + if ((NSEC_PER_SEC % HZ) != 0 && + div_u64(timeout_nsec, NSEC_PER_SEC) >= MAX_JIFFY_OFFSET / HZ) + return MAX_JIFFY_OFFSET; + + return min_t(u64, MAX_JIFFY_OFFSET, nsecs_to_jiffies64(timeout_nsec) + 1); +} +EXPORT_SYMBOL(drm_timeout_rel_to_jiffies); diff --git a/include/drm/drm_utils.h b/include/drm/drm_utils.h index 6a46f755daba..8c0cc9835413 100644 --- a/include/drm/drm_utils.h +++ b/include/drm/drm_utils.h @@ -25,5 +25,6 @@ const struct drm_panel_backlight_quirk * drm_get_panel_backlight_quirk(const struct drm_edid *edid); signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec); +unsigned long drm_timeout_rel_to_jiffies(u64 timeout_nsec); #endif -- 2.55.0