From patchwork Thu Apr 24 14:13:09 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Karim Manaouil X-Patchwork-Id: 884046 Received: from mail-wr1-f42.google.com (mail-wr1-f42.google.com [209.85.221.42]) (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 9F8FB1A5BBD for ; Thu, 24 Apr 2025 14:13:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.42 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745504031; cv=none; b=hJfORtUFmiaccYrGSg44Ljek3unh8HR5/wgHJE4ZYmWFpL4GTZqkBeXhDRy6ziGIGJJJ1+dYwSBWqXSrWtGoq7E3lU82EvY1dAbfGnLKZep86re1xSsQqZPp4azenHyTZD6R10z/I2CM3ykk0t9g4GB8Fd3Hz6BV76F0ePHVKpE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745504031; c=relaxed/simple; bh=CvFb1okbnEK9wiiZwwdcGSqHE02tQmbzZOFs1CBcYGk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=kpeVBIU/nJh1lHegoXCqG2Em+sZbnii6HTgkWIt0deM9ccNhj08CK4fgCfI/eYFzT40bpO4j4jeviQnmfNXONry1ygERhBewig4dvPH/zUMmFP32EMzEtC0HFcZleMcTAYuD9nsFCXvnhqhAe6JfAHSJXbfnya33uY4SIOsfYDk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=iLOwI++f; arc=none smtp.client-ip=209.85.221.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="iLOwI++f" Received: by mail-wr1-f42.google.com with SMTP id ffacd0b85a97d-3912fdddf8fso1551218f8f.1 for ; Thu, 24 Apr 2025 07:13:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1745504028; x=1746108828; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=hvXrACbOQaGlhym8epnVf2FRavXrOILN2RCY7mrPgRw=; b=iLOwI++fMXomw84Au6sHZmvf4XEzvfBtSvOEbGXBg1IqUMdLW0+v/JK3OSvPQBiK07 G7DAOlkh3Dn7nSPFwYfcmRBHN4JhU6Z7fOWSzh4GJgLLSKO1hmkm6NG5WZH0AfoEC9Bo NaVFDFNV39iAFQcXUNIXRLyqVzXYxsfBRnVLgKEH3URDsPi8jYpP5eiVPiklRMRJO+fD KUIEEE9ixPIFXkDrY/7Qt3c6/QbTS76DZoKYstIM7n24LZL98RND02LEMC+RNX+PpEON PTHZTJSA7cSemMaHjeV4uQBh4Xu/4+vnuIYtqe3zD61Dyl0L28stdByuBTQVTBs9JVfw TXHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1745504028; x=1746108828; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=hvXrACbOQaGlhym8epnVf2FRavXrOILN2RCY7mrPgRw=; b=wB0468jp2vSZm2eiK+xXakThBV7qJ1wiG5oWb86qYZhrfzxODQOjcLrQBnu+w/0OTO AwEWgpxjAHuK627nuxWX7bnojdQhAorBfy06dM5KW4CfTYZ2lVBWgHHAbdWLhbtddGAn 7zPnZV50lyWFhmWpBIEf8KxCSJOKKcGQMPkTxDTggmQqa5tbBSEMcZ6fjzDqyV8KC5sf GBHRQHzhj+hf9weY+kX6RwQodZRjJ9jVmQFY/S34YWO37HwdXESIgJ0xVsanFMAxCGcp 8THud6FtpNtz4zPrb4eXuqI9oagbOOetZtO/gesHV87ShlNG2Z0DyBkko5GXu7u+zj07 /CyQ== X-Forwarded-Encrypted: i=1; AJvYcCWNFu7PZocSwNwZsfsclmCiMyKQMA8vddbI8geqZ0xvHVxpUlwXaQCgnDvObIu63qsAiWF1BaxK8iOzo1rI@vger.kernel.org X-Gm-Message-State: AOJu0Yy0kpucxj3k2KU8SNn5s2+srWTEGYNt20/Cw2vl/W21MkQZEMx5 5txrwjdJu6RAcJmxx5RJkoU6l07CzKAc8wImR0utd1AQWTaIXW7d818D6fTZ988= X-Gm-Gg: ASbGncvhuznOZCFRJNns5QZMzLwpk0E5ij0TWSOz8OlstL276boDESaikSS+KtkSIoo NwBhPXzaLwHQd+n9IW3UTsLom+MkwwHAVuwGnVSxe3WCIg/DUIIOW1sbQiIfC9Hk8QmeNtfEHNU o6e+7+nkbQZ4dJ2k23QwbyZrTKZUn8bvFaPmMAmchn32GO0UpFQhYpGjox1kpPG5Y9D8+X7t7TA TIXfrdcCMK3+y1sk5S7igpHtD0zee4oCJAqO1B3dRXLActU94SW8lf/crt2PaWrTQG/IRAELQKY S4S/gnGT+RtVrw7/Qn98QpkyV03Qoarf+Of3Fr1enRRC7M8noX8tRiBvty/WPFfBSTPy/ixNGqX s8Vi+t7FwTHRLClWMncVZ/s203MI= X-Google-Smtp-Source: AGHT+IEBkZ1IBJCII/ywyTdMC0fLKprAp65skAqA7s+zC8i8AN1EGINZeECW9VcRyNwMhKCFTJTxcg== X-Received: by 2002:adf:fb4c:0:b0:391:1218:d5f4 with SMTP id ffacd0b85a97d-3a06d698d62mr2225510f8f.23.1745504027803; Thu, 24 Apr 2025 07:13:47 -0700 (PDT) Received: from seksu.systems-nuts.com (stevens.inf.ed.ac.uk. [129.215.164.122]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3a06d4a8150sm2199951f8f.7.2025.04.24.07.13.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Apr 2025 07:13:47 -0700 (PDT) From: Karim Manaouil To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Cc: Karim Manaouil , Alexander Graf , Alex Elder , Catalin Marinas , Fuad Tabba , Joey Gouly , Jonathan Corbet , Marc Zyngier , Mark Brown , Mark Rutland , Oliver Upton , Paolo Bonzini , Prakruthi Deepak Heragu , Quentin Perret , Rob Herring , Srinivas Kandagatla , Srivatsa Vaddagiri , Will Deacon , Haripranesh S , Carl van Schaik , Murali Nalajala , Sreenivasulu Chalamcharla , Trilok Soni , Stefan Schmidt Subject: [RFC PATCH 02/34] KVM: irqfd: Add architecture hooks for irqfd allocation and initialization Date: Thu, 24 Apr 2025 15:13:09 +0100 Message-Id: <20250424141341.841734-3-karim.manaouil@linaro.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250424141341.841734-1-karim.manaouil@linaro.org> References: <20250424141341.841734-1-karim.manaouil@linaro.org> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Some KVM backends, such as Gunyah, require irqfd structures to carry platform-specific state or setup logic. To support these use cases, introduce three weakly-defined functions: - kvm_arch_irqfd_alloc() - kvm_arch_irqfd_free() - kvm_arch_irqfd_init() These allow KVM backends to override irqfd allocation, teardown, and initialization logic. The default implementations simply allocate/finalize a standard `struct kvm_kernel_irqfd`, maintaining existing behaviour. This change is required by the Gunyah backend, which uses these hooks to associate irqfd objects with Gunyah-specific bell resource handles for IRQ injection via hypercalls. Signed-off-by: Karim Manaouil --- include/linux/kvm_irqfd.h | 4 ++++ virt/kvm/eventfd.c | 31 ++++++++++++++++++++++++++++--- 2 files changed, 32 insertions(+), 3 deletions(-) diff --git a/include/linux/kvm_irqfd.h b/include/linux/kvm_irqfd.h index 8ad43692e3bb..e8d21d443c58 100644 --- a/include/linux/kvm_irqfd.h +++ b/include/linux/kvm_irqfd.h @@ -61,4 +61,8 @@ struct kvm_kernel_irqfd { struct irq_bypass_producer *producer; }; +struct kvm_kernel_irqfd *kvm_arch_irqfd_alloc(void); +void kvm_arch_irqfd_free(struct kvm_kernel_irqfd *irqfd); +int kvm_arch_irqfd_init(struct kvm_kernel_irqfd *irqfd); + #endif /* __LINUX_KVM_IRQFD_H */ diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index 11e5d1e3f12e..5f3776a1b960 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -32,6 +32,24 @@ static struct workqueue_struct *irqfd_cleanup_wq; +struct kvm_kernel_irqfd __attribute__((weak)) +*kvm_arch_irqfd_alloc(void) +{ + return kzalloc(sizeof(struct kvm_kernel_irqfd), GFP_KERNEL_ACCOUNT); +} + +void __attribute__((weak)) +kvm_arch_irqfd_free(struct kvm_kernel_irqfd *irqfd) +{ + kfree(irqfd); +} + +int __attribute__((weak)) +kvm_arch_irqfd_init(struct kvm_kernel_irqfd *irqfd) +{ + return 0; +} + bool __attribute__((weak)) kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args) { @@ -153,7 +171,7 @@ irqfd_shutdown(struct work_struct *work) irq_bypass_unregister_consumer(&irqfd->consumer); #endif eventfd_ctx_put(irqfd->eventfd); - kfree(irqfd); + kvm_arch_irqfd_free(irqfd); } @@ -315,7 +333,7 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args) if (!kvm_arch_irqfd_allowed(kvm, args)) return -EINVAL; - irqfd = kzalloc(sizeof(*irqfd), GFP_KERNEL_ACCOUNT); + irqfd = kvm_arch_irqfd_alloc(); if (!irqfd) return -ENOMEM; @@ -396,6 +414,13 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args) init_waitqueue_func_entry(&irqfd->wait, irqfd_wakeup); init_poll_funcptr(&irqfd->pt, irqfd_ptable_queue_proc); + /* + * Give a chance to archiectures to finish initilization. + * E.g. Gunyah needs to register a resource ticket for this irq. + */ + if (kvm_arch_irqfd_init(irqfd)) + goto fail; + spin_lock_irq(&kvm->irqfds.lock); ret = 0; @@ -452,7 +477,7 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args) eventfd_ctx_put(eventfd); out: - kfree(irqfd); + kvm_arch_irqfd_free(irqfd); return ret; }