From nobody Sat Feb 7 19:41:40 2026 Received: from mail-wm1-f54.google.com (mail-wm1-f54.google.com [209.85.128.54]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2797120B7ED for ; Tue, 3 Feb 2026 13:00:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.54 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770123657; cv=none; b=JmRBSyMj91j7O4n8CKS3Ed9lbvrXBRQCkvi9UieYccuDJoRNphN216zuzcqGJyuq4zEjLBBz93jXdEegIyso9RoiU9Kqbn8FoZ0+fHc/eNQB/7tLcVmOgEbSBJTKH1HUwZDqFdHaeil/jHKze1RftGfjUBKp2RxVpZH91AhkHVQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770123657; c=relaxed/simple; bh=bjhxM7cFwGkKS2BZNc+CrEavaUZjQgYiUP9WQm4pkRI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=qbu7wMcuv4H0tda4iCJBs/eVNrIF5MuVA3HbiKooTiSxx++bBQCrG+YRnNxs5SYTfffDSbFrgpR37RQLep5XgKjJf58/WtnM9U7L01Gn9ktUT+WEsUwo0cu+lowqco647erdGVK2y4/e9wZ4sy8WlAvTBnekL2fVH5ujFaq2JWk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=SxHVMkOr; arc=none smtp.client-ip=209.85.128.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SxHVMkOr" Received: by mail-wm1-f54.google.com with SMTP id 5b1f17b1804b1-48068ed1eccso51768445e9.2 for ; Tue, 03 Feb 2026 05:00:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1770123654; x=1770728454; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=AsUIVOzdDRdVEL17P1YS6XyOc6ergbsNaCqKh0AjEKo=; b=SxHVMkOrG4t90Gpe9WLEnrT4k9QIZbZGSaQ63E4Bf5/RZR6ageVWds+lwyYmtvCWtb Ns7QB5487vIf3xwuYTtDu1qRQUrNDXb3uxZm91q1QKxfQ4VjExeukslkjKK5Og0yHFDj yuXor2ecQMcoKdzuzWyvmRzfUcz0EuQJ+8UBYiKpmBYRtKwt1yp3t2DxtYvlIYtvopAK vplQlS334zoA2HzUjc1VptSHOk/ZPrz/6e2BpV596+1IPm7dLitvpksQOn/vD3bxQOy1 R2PaVuVgBXUkRbAfDCChCPY0/TRBfovF8P8zsVB2UoRi+CZop24sBIUQDp2iUIiwFL7c uBBA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770123654; x=1770728454; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=AsUIVOzdDRdVEL17P1YS6XyOc6ergbsNaCqKh0AjEKo=; b=ErJxOtn67R6YzYlgtyVuDT1laLtkG/AOg6TXkPBVVkgLvwid89MUkNpyIIUhu3Fljk cujJYs/HDQPFAjt/TmEB8vPPhCOnnZSQWir9oOZK63s1iTDwlVySJ908aLJEiJf+8lQN PY/pthQgNs7DRo518/QiFZhTQt0NN97UIMpYmY5+cfRCfCr0F5IEEzVWoYppGxqIxhHV ZQgo5OafOqnHTZICKCd6C2E+jusHz/9TEpvkLl0jfVf3keWafhDXRbwF1T9JLrXpGp9H GcMUyLqIPMze39GUofzNGN8XDmIUjJWHuhCOLAT1avBvm+GemWlBYSGhsBkyh0GIcR9U nqOw== X-Forwarded-Encrypted: i=1; AJvYcCVFcXwsSFpqMfhrX1qwNi1V19DiO1YSEHzJ9hagHFErn3UCSyJmOZE1cejvtvQJamwktnoqGB9Bl2yysDU=@vger.kernel.org X-Gm-Message-State: AOJu0YwW+uV6nQ8Fp81Z+iRa49QVnqAH2Q/tQz0kfUvwwajGefPT4KBa 7w71LUdI2dhgty9fd5CgREIAPunz8hVa+ziL/tIeA1xDpElQk2noUV+s X-Gm-Gg: AZuq6aJ+fs7zJciTmRTyrV+g/TRRWTQtRqWiWp9mQ6HvCwMu2+Cyni9uL0SHFfPrnSy LR21gsx0yQG2CVfOPwqv9OCU8hRJMKF2g003U3p07zZOIsk6bIBUPFWIK8XhG/vg9WHiynkzYng 5uVlYZKCYV2NSWFHZTmnrFfJN5BjWfR4Pe3ox1dOdnYy+W5275yJdcZVZN2GOtP2kob7ibDgC3o OEp+G7nVq9ZY9rESeqNYpoKlVJ+KTV3tJ3pTLAM2Ll/c8xwMtY3PcU9ogpwVTr4EumDt0xRecF8 jHmt8il3KHMmmjwww6IWdpmY5FUf4T4gD1T2KaSd0/Oip3TQpeQ3BinpNk0rkEYWsoqgtfWAZg3 3ALZLU/tZQyC5Y/2ZYWT56tjCIuDgQJKwRMWBQ1DXKp91E1SZk2tvImZKq1ickvFbHLz+ENVV27 sJk51Fte0Q+bfot3vcZs0yxbEYhBd0oBPZ3idww3T+okJIqVvRsp/pNhLwVuqH8g== X-Received: by 2002:a05:600c:4e12:b0:477:c478:46d7 with SMTP id 5b1f17b1804b1-482db481c85mr206809705e9.22.1770123654157; Tue, 03 Feb 2026 05:00:54 -0800 (PST) Received: from f.. (cst-prg-85-136.cust.vodafone.cz. [46.135.85.136]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-482e047d863sm125188435e9.1.2026.02.03.05.00.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Feb 2026 05:00:53 -0800 (PST) From: Mateusz Guzik To: viro@zeniv.linux.org.uk Cc: brauner@kernel.org, jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH] fs: add porting notes about readlink_copy() Date: Tue, 3 Feb 2026 14:00:31 +0100 Message-ID: <20260203130032.315177-1-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Calling convention has changed in ea382199071931d1 ("vfs: support caching = symlink lengths in inodes") Signed-off-by: Mateusz Guzik --- Documentation/filesystems/porting.rst | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesyst= ems/porting.rst index 3397937ed838..bd4128ccbb67 100644 --- a/Documentation/filesystems/porting.rst +++ b/Documentation/filesystems/porting.rst @@ -1334,3 +1334,13 @@ end_creating() and the parent will be unlocked preci= sely when necessary. =20 kill_litter_super() is gone; convert to DCACHE_PERSISTENT use (as all in-tree filesystems have done). + +--- + +**mandatory** + +readlink_copy() now requires link length as the 4th argument. Said length = needs +to match what strlen() would return if it was ran on the string. + +However, if the string is freely accessible for the duration of inode's +lifetime, consider using inode_set_cached_link() instead. --=20 2.43.0