From patchwork Tue May 29 16:22:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 922227 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=kvm-ppc-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="yuLsp3vO"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 40wJsv3kPRz9s2S for ; Wed, 30 May 2018 02:22:43 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965005AbeE2QW2 (ORCPT ); Tue, 29 May 2018 12:22:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:48518 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935416AbeE2QW1 (ORCPT ); Tue, 29 May 2018 12:22:27 -0400 Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 16B832086A; Tue, 29 May 2018 16:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1527610947; bh=zQ/FiplCphV8/MbGTCR7ru52usgCiC0vwUrznW1f3Fs=; h=From:To:Cc:Subject:Date:From; b=yuLsp3vOAteyyU8AYpxVncKOaOcBy3zwgUY9UlDo4LuU8DS0sx69KMIRN1Ew/0Ovo UPPkfVVj0xxozYsfULh1Dmdc1UCUMI00yN8V/xkA40NT2Z8Yxkp2iD7G90BLa7jc9o EEo+sJJcONyCc68YSkQVwvbMZfWT80ussXX5+RRU= From: Greg Kroah-Hartman To: kvm@vger.kernel.org Cc: Greg Kroah-Hartman , Paul Mackerras , Benjamin Herrenschmidt , Michael Ellerman , Christoffer Dall , Marc Zyngier , Paolo Bonzini , =?utf-8?q?Radim_Kr=C4=8Dm?= =?utf-8?b?w6HFmQ==?= , Arvind Yadav , Eric Auger , Andre Przywara , kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Subject: [PATCH] kvm: no need to check return value of debugfs_create functions Date: Tue, 29 May 2018 18:22:04 +0200 Message-Id: <20180529162204.11757-1-gregkh@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 MIME-Version: 1.0 Sender: kvm-ppc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. This cleans up the error handling a lot, as this code will never get hit. Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Michael Ellerman Cc: Christoffer Dall Cc: Marc Zyngier Cc: Paolo Bonzini Cc: "Radim Krčmář" Cc: Arvind Yadav Cc: Eric Auger Cc: Andre Przywara Cc: kvm-ppc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kvm/book3s_hv.c | 3 +-- virt/kvm/arm/vgic/vgic-debug.c | 17 ++++----------- virt/kvm/arm/vgic/vgic.h | 4 ++-- virt/kvm/kvm_main.c | 40 +++++++--------------------------- 4 files changed, 15 insertions(+), 49 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 4d07fca5121c..67d7de1470cc 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3950,8 +3950,7 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm) */ snprintf(buf, sizeof(buf), "vm%d", current->pid); kvm->arch.debugfs_dir = debugfs_create_dir(buf, kvm_debugfs_dir); - if (!IS_ERR_OR_NULL(kvm->arch.debugfs_dir)) - kvmppc_mmu_debugfs_init(kvm); + kvmppc_mmu_debugfs_init(kvm); return 0; } diff --git a/virt/kvm/arm/vgic/vgic-debug.c b/virt/kvm/arm/vgic/vgic-debug.c index 10b38178cff2..0140b29079b6 100644 --- a/virt/kvm/arm/vgic/vgic-debug.c +++ b/virt/kvm/arm/vgic/vgic-debug.c @@ -263,21 +263,12 @@ static const struct file_operations vgic_debug_fops = { .release = seq_release }; -int vgic_debug_init(struct kvm *kvm) +void vgic_debug_init(struct kvm *kvm) { - if (!kvm->debugfs_dentry) - return -ENOENT; - - if (!debugfs_create_file("vgic-state", 0444, - kvm->debugfs_dentry, - kvm, - &vgic_debug_fops)) - return -ENOMEM; - - return 0; + debugfs_create_file("vgic-state", 0444, kvm->debugfs_dentry, kvm, + &vgic_debug_fops); } -int vgic_debug_destroy(struct kvm *kvm) +void vgic_debug_destroy(struct kvm *kvm) { - return 0; } diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h index 830e815748a0..3c38c5349953 100644 --- a/virt/kvm/arm/vgic/vgic.h +++ b/virt/kvm/arm/vgic/vgic.h @@ -229,8 +229,8 @@ void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr); int vgic_lazy_init(struct kvm *kvm); int vgic_init(struct kvm *kvm); -int vgic_debug_init(struct kvm *kvm); -int vgic_debug_destroy(struct kvm *kvm); +void vgic_debug_init(struct kvm *kvm); +void vgic_debug_destroy(struct kvm *kvm); bool lock_all_vcpus(struct kvm *kvm); void unlock_all_vcpus(struct kvm *kvm); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c7b2e927f699..0ad400f353fc 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -572,10 +572,7 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, int fd) return 0; snprintf(dir_name, sizeof(dir_name), "%d-%d", task_pid_nr(current), fd); - kvm->debugfs_dentry = debugfs_create_dir(dir_name, - kvm_debugfs_dir); - if (!kvm->debugfs_dentry) - return -ENOMEM; + kvm->debugfs_dentry = debugfs_create_dir(dir_name, kvm_debugfs_dir); kvm->debugfs_stat_data = kcalloc(kvm_debugfs_num_entries, sizeof(*kvm->debugfs_stat_data), @@ -591,11 +588,8 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, int fd) stat_data->kvm = kvm; stat_data->offset = p->offset; kvm->debugfs_stat_data[p - debugfs_entries] = stat_data; - if (!debugfs_create_file(p->name, 0644, - kvm->debugfs_dentry, - stat_data, - stat_fops_per_vm[p->kind])) - return -ENOMEM; + debugfs_create_file(p->name, 0644, kvm->debugfs_dentry, + stat_data, stat_fops_per_vm[p->kind]); } return 0; } @@ -3896,29 +3890,18 @@ static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm) kfree(env); } -static int kvm_init_debug(void) +static void kvm_init_debug(void) { - int r = -EEXIST; struct kvm_stats_debugfs_item *p; kvm_debugfs_dir = debugfs_create_dir("kvm", NULL); - if (kvm_debugfs_dir == NULL) - goto out; kvm_debugfs_num_entries = 0; for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) { - if (!debugfs_create_file(p->name, 0644, kvm_debugfs_dir, - (void *)(long)p->offset, - stat_fops[p->kind])) - goto out_dir; + debugfs_create_file(p->name, 0644, kvm_debugfs_dir, + (void *)(long)p->offset, + stat_fops[p->kind]); } - - return 0; - -out_dir: - debugfs_remove_recursive(kvm_debugfs_dir); -out: - return r; } static int kvm_suspend(void) @@ -4046,20 +4029,13 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, kvm_preempt_ops.sched_in = kvm_sched_in; kvm_preempt_ops.sched_out = kvm_sched_out; - r = kvm_init_debug(); - if (r) { - pr_err("kvm: create debugfs files failed\n"); - goto out_undebugfs; - } + kvm_init_debug(); r = kvm_vfio_ops_init(); WARN_ON(r); return 0; -out_undebugfs: - unregister_syscore_ops(&kvm_syscore_ops); - misc_deregister(&kvm_dev); out_unreg: kvm_async_pf_deinit(); out_free: