From 929f45e32499171ce3e5a15db972256eac513ad7 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 29 May 2018 18:22:04 +0200 Subject: [PATCH] kvm: no need to check return value of debugfs_create functions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 KrÄmář" 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 Signed-off-by: Paolo Bonzini --- 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 4ffc0b5e6105..c589d4c2b478 100644 --- a/virt/kvm/arm/vgic/vgic-debug.c +++ b/virt/kvm/arm/vgic/vgic-debug.c @@ -264,21 +264,12 @@ 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 6879cf48652a..ead00b2072b2 100644 --- a/virt/kvm/arm/vgic/vgic.h +++ b/virt/kvm/arm/vgic/vgic.h @@ -250,8 +250,8 @@ 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 8938c9e553df..aa7da1d8ece2 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -590,10 +590,7 @@ 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), @@ -609,11 +606,8 @@ 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; } @@ -3919,29 +3913,18 @@ 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) @@ -4069,20 +4052,13 @@ 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: