From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f73.google.com (mail-wr1-f73.google.com [209.85.221.73]) (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 5DCC31DE8AA for ; Wed, 20 Nov 2024 14:56:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732114596; cv=none; b=HkNldJBwh57P59fMP+egFQ8w7z2SuE8E/LzR+/yOtN8v7P8f59mLtrWBX5GbZTir4gbLIUB/2wZOtSw4q0Cb9MML84EEOpvSIIdOb7h94K1jA4XBpSPdFgK6XD0XyiIqkWeznHq2lr/cqJQ7k2a67TdSlMv6/M+PHYbqHvqjdMo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732114596; c=relaxed/simple; bh=GSw09bqyA6K1PcCK8gagOT2XwF7uH8Q/0z1wyixcHDs=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=WfSFc68JHUxCkxX1imOn3f8bMlGGpYTR5QYF44ZkXSVOtYNMFw8QKJORyiwBDO7YD5/0uj1Fm3aLsrhevAFoCI0BFx2+pSVC9FRZCgiqUWJmez9flIYvSstpZJ1nxwDhqb8dBTkmRTwzddj+nQShxFd9U6XDtawNJkxI8eg1ick= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=u2FNQqq9; arc=none smtp.client-ip=209.85.221.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="u2FNQqq9" Received: by mail-wr1-f73.google.com with SMTP id ffacd0b85a97d-382412f3e62so2043042f8f.3 for ; Wed, 20 Nov 2024 06:56:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1732114593; x=1732719393; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=aBJMJ0qYrky91mwQ0u5syokhvobq81rvT/hL+9f8jt4=; b=u2FNQqq9bZTA3zzHIX9y/qMMAYIC1agoD2biJiFH/RJh4wDWrLYlK5ncZ5H2R7dJzT HkEzkjqR1U3i7yD9I0rO6/FqZFsOUuT1od8YS4SQAAbzttsZeXIsy2Dwf2qQZY6gHA9a kDo4uJkP8GRzfwqcKzn9OH3ZNSjwSXvaIZYC9qFVdPPP62B2nVfa9VO/YhKHnE5oSi4/ iDTz+4fe6WSfT2yzZFMCBL8eCahI0K+5vzidvaTVnEvDmu6ywiLFmpHjVPTB8bFjZdwS zOuyKNocKhkVsXzp5AFFgJExdJiRHSaW1JEpsXT9caZ6dgyNOAcbDaLddfg1+ix8bfYE qi7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1732114593; x=1732719393; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=aBJMJ0qYrky91mwQ0u5syokhvobq81rvT/hL+9f8jt4=; b=dFK66g35SpmyAa2Yz7Tbx+FAPoYxWCRfUDUf2r5IiAs92n45yPgUa0yeO+2rSajgvK 574ZM5o2CnAWHVfMedEiLHSeLDSKMEKXiSxZtk6E3yz9S6FsvvO8TYNHVWckBWlMNLr9 tsSQ9+7XUO8Uka6nuFjJg5UVG+xQHNDwSLrmotjgdGn/I3BBGMYiufQ+2QBIm3OasYiC c7xsFvbN0PpiI07XzuO544hLW3M+knJZMf52LbedJBzkccvGZOcWZvQ8XAQxzcJkgh2J A/Va5LQ5AkCt9YJGrYM8OsrVojHb35/Mox9uJ+YbswKmCkxcoZaJF3CTTQCOpuzomC3L gEyg== X-Forwarded-Encrypted: i=1; AJvYcCXYPAiglszNGJh9ztU++I/h9Kpqebwp/iC/qfRoER7mX33Q6elr2G2SbD9AdHpY5QbPrhQKtoRA7NPSaGg=@vger.kernel.org X-Gm-Message-State: AOJu0YwEr+I8sWwzKLlpICS5T98TJxfhKjxWX6DNm7IeDoACS59eB5zt 98mOEvTlYOhARLrrvitXjoiO8R7eH9CKoBRlIign/Y0YYapC9HNdhTQrfD8fmAsBrk2lALQYhZ9 AKWONPhibD4R+dA== X-Google-Smtp-Source: AGHT+IHg6gC2fHXTfoa8HybdbCejL4Hw2wCXFWVyfLSy/FMj3wKsyFBkjC9iLS8+VOnYGq57+fL7fZy03dC8naI= X-Received: from aliceryhl.c.googlers.com ([fda3:e722:ac3:cc00:68:fe9:ac10:f29e]) (user=aliceryhl job=sendgmr) by 2002:a05:6000:148:b0:382:3745:e843 with SMTP id ffacd0b85a97d-38254a8593dmr859f8f.0.1732114592756; Wed, 20 Nov 2024 06:56:32 -0800 (PST) Date: Wed, 20 Nov 2024 14:50:01 +0000 In-Reply-To: <20241120-vma-v8-0-eb31425da66b@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241120-vma-v8-0-eb31425da66b@google.com> X-Developer-Key: i=aliceryhl@google.com; a=openpgp; fpr=49F6C1FAA74960F43A5B86A1EE7A392FDE96209F X-Developer-Signature: v=1; a=openpgp-sha256; l=2667; i=aliceryhl@google.com; h=from:subject:message-id; bh=GSw09bqyA6K1PcCK8gagOT2XwF7uH8Q/0z1wyixcHDs=; b=owEBbQKS/ZANAwAKAQRYvu5YxjlGAcsmYgBnPfiM46FQ43oKCfz0YbqQO2Vr66Kdgk66Jo5tx JPUulsyfy+JAjMEAAEKAB0WIQSDkqKUTWQHCvFIvbIEWL7uWMY5RgUCZz34jAAKCRAEWL7uWMY5 RkXqEACEB7yn2mFW0lgsKxYBQ4qe2+54UutRvkGiIwc8wfu0WgQ+1KUd04XtaEmpyHADZ+itLu4 w1PUr+Qf3HccuAeWtsE12ckyvdIacsnpDEl73ajj1jGwJsZwDgM27DJB3Pe9OaB8FTOZAPbaLEZ JOmLqMLXCULYc26n3q9/Yb/FMwV41XYcxFPovNlq16vpbsQ0PTY9A//QKAhhINkxA+HD6etiNf+ bMN7aL4D5wJW9KHNeA+ubufEouX8yDKZF21ft/+ZyGHSs2bL6qlhwG2ZUly0H8wtI6G0XHciaNh xe2agSElixu2sn+THcpulk9QebWT0nAW3alVucVH8TVZPzXB04MQdA1cMzSxg8yHCSlRdWdCtAi jJfO979h+KcrnKE2+KMi6YV1lr9SEcLHt8q12IeUWIZDUD7Bb8JAC9zi5B67xB11hl2HA4kfdZm jo5jJp9K3lAgAmFrxIhr5PhOpPUauxswnhtFQLl40gmlHRUFh6eOngHO/oMoCLRqKY3hRlw8nv2 MIK9KFyNCYT2SFWifeBNJ575bVLcsnE9ESTUpSgsQU1V1SfWI+UENNWsPrxUd+sIY4rYkGrSTn4 1ptpfZuhqYA6ZNOY9B2j2hhTh0rf1jOBrWFkm0AuSio6VJCdcqB3J4dmzMR4zSY6VslhXm/+yV+ q10Bd9/rJyXui7A== X-Mailer: b4 0.13.0 Message-ID: <20241120-vma-v8-7-eb31425da66b@google.com> Subject: [PATCH v8 7/7] rust: miscdevice: add mmap support From: Alice Ryhl To: Miguel Ojeda , Matthew Wilcox , Lorenzo Stoakes , Vlastimil Babka , John Hubbard , "Liam R. Howlett" , Andrew Morton , Greg Kroah-Hartman , Arnd Bergmann , Christian Brauner Cc: Alex Gaynor , Boqun Feng , Gary Guo , "=?utf-8?q?Bj=C3=B6rn_Roy_Baron?=" , Benno Lossin , linux-kernel@vger.kernel.org, linux-mm@kvack.org, rust-for-linux@vger.kernel.org, Alice Ryhl , Andreas Hindborg Content-Type: text/plain; charset="utf-8" Using the vma support introduced by the previous commit, introduce mmap support for miscdevices. The mmap call is given a vma that is undergoing initial setup, so the VmAreaNew type is used. Signed-off-by: Alice Ryhl --- rust/kernel/miscdevice.rs | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs index 7e2a79b3ae26..4e4b9476e092 100644 --- a/rust/kernel/miscdevice.rs +++ b/rust/kernel/miscdevice.rs @@ -11,6 +11,7 @@ use crate::{ bindings, error::{to_result, Error, Result, VTABLE_DEFAULT_ERROR}, + mm::virt::VmAreaNew, prelude::*, str::CStr, types::{ForeignOwnable, Opaque}, @@ -110,6 +111,11 @@ fn release(device: Self::Ptr) { drop(device); } + /// Handle for mmap. + fn mmap(_device: ::Borrowed<'_>, _vma: &VmAreaNew) -> Result { + kernel::build_error(VTABLE_DEFAULT_ERROR) + } + /// Handler for ioctls. /// /// The `cmd` argument is usually manipulated using the utilties in [`kernel::ioctl`]. @@ -156,6 +162,7 @@ impl VtableHelper { const VTABLE: bindings::file_operations = bindings::file_operations { open: Some(fops_open::), release: Some(fops_release::), + mmap: maybe_fn(T::HAS_MMAP, fops_mmap::), unlocked_ioctl: maybe_fn(T::HAS_IOCTL, fops_ioctl::), #[cfg(CONFIG_COMPAT)] compat_ioctl: if T::HAS_COMPAT_IOCTL { @@ -216,6 +223,27 @@ impl VtableHelper { 0 } +/// # Safety +/// +/// `file` must be a valid file that is associated with a `MiscDeviceRegistration`. +/// `vma` must be a vma that is currently being mmap'ed with this file. +unsafe extern "C" fn fops_mmap( + file: *mut bindings::file, + vma: *mut bindings::vm_area_struct, +) -> c_int { + // SAFETY: The mmap call of a file can access the private data. + let private = unsafe { (*file).private_data }; + // SAFETY: Mmap calls can borrow the private data of the file. + let device = unsafe { ::borrow(private) }; + // SAFETY: The caller provides a vma that is undergoing initial VMA setup. + let area = unsafe { VmAreaNew::from_raw(vma) }; + + match T::mmap(device, area) { + Ok(()) => 0, + Err(err) => err.to_errno() as c_int, + } +} + /// # Safety /// /// `file` must be a valid file that is associated with a `MiscDeviceRegistration`. -- 2.47.0.371.ga323438b13-goog