| Message ID | 20191024230744.14543-8-sean.j.christopherson@intel.com |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | KVM: Dynamically size memslot arrays | expand |
On 10/25/19 1:07 AM, Sean Christopherson wrote: > Replace a big pile o' gotos with returns to make it more obvious what > error code is being returned, and to prepare for refactoring the > functional, i.e. post-checks, portion of __kvm_set_memory_region(). > > Reviewed-by: Janosch Frank <frankja@linux.ibm.com> > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> > --- > virt/kvm/kvm_main.c | 40 ++++++++++++++++++---------------------- > 1 file changed, 18 insertions(+), 22 deletions(-) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index a43902d9036d..e2f47d60f696 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -942,34 +942,33 @@ int __kvm_set_memory_region(struct kvm *kvm, > > r = check_memory_region_flags(mem); > if (r) > - goto out; > + return r; > > - r = -EINVAL; > as_id = mem->slot >> 16; > id = (u16)mem->slot; > > /* General sanity checks */ > if (mem->memory_size & (PAGE_SIZE - 1)) > - goto out; > + return -EINVAL; > if (mem->guest_phys_addr & (PAGE_SIZE - 1)) > - goto out; > + return -EINVAL; > /* We can read the guest memory with __xxx_user() later on. */ > if ((id < KVM_USER_MEM_SLOTS) && > ((mem->userspace_addr & (PAGE_SIZE - 1)) || > !access_ok((void __user *)(unsigned long)mem->userspace_addr, > mem->memory_size))) > - goto out; > + return -EINVAL; > if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM) > - goto out; > + return -EINVAL; > if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr) > - goto out; > + return -EINVAL; > > slot = id_to_memslot(__kvm_memslots(kvm, as_id), id); > base_gfn = mem->guest_phys_addr >> PAGE_SHIFT; > npages = mem->memory_size >> PAGE_SHIFT; > > if (npages > KVM_MEM_MAX_NR_PAGES) > - goto out; > + return -EINVAL; > > new = old = *slot; > > @@ -986,20 +985,18 @@ int __kvm_set_memory_region(struct kvm *kvm, > if ((new.userspace_addr != old.userspace_addr) || > (npages != old.npages) || > ((new.flags ^ old.flags) & KVM_MEM_READONLY)) > - goto out; > + return -EINVAL; > > if (base_gfn != old.base_gfn) > change = KVM_MR_MOVE; > else if (new.flags != old.flags) > change = KVM_MR_FLAGS_ONLY; > - else { /* Nothing to change. */ > - r = 0; > - goto out; > - } > + else /* Nothing to change. */ > + return 0; > } > } else { > if (!old.npages) > - goto out; > + return -EINVAL; > > change = KVM_MR_DELETE; > new.base_gfn = 0; > @@ -1008,29 +1005,29 @@ int __kvm_set_memory_region(struct kvm *kvm, > > if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) { > /* Check for overlaps */ > - r = -EEXIST; > kvm_for_each_memslot(slot, __kvm_memslots(kvm, as_id)) { > if (slot->id == id) > continue; > if (!((base_gfn + npages <= slot->base_gfn) || > (base_gfn >= slot->base_gfn + slot->npages))) > - goto out; > + return -EEXIST; > } > } > > - r = -ENOMEM; > - > /* Allocate/free page dirty bitmap as needed */ > if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES)) > new.dirty_bitmap = NULL; > else if (!new.dirty_bitmap) { > - if (kvm_create_dirty_bitmap(&new) < 0) > - goto out; > + r = kvm_create_dirty_bitmap(&new); > + if (r) > + return r; Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> > } > > slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT); > - if (!slots) > + if (!slots) { > + r = -ENOMEM; > goto out_bitmap; > + } > memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots)); > > if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) { > @@ -1081,7 +1078,6 @@ int __kvm_set_memory_region(struct kvm *kvm, > out_bitmap: > if (new.dirty_bitmap && !old.dirty_bitmap) > kvm_destroy_dirty_bitmap(&new); > -out: > return r; > } > EXPORT_SYMBOL_GPL(__kvm_set_memory_region); >
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a43902d9036d..e2f47d60f696 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -942,34 +942,33 @@ int __kvm_set_memory_region(struct kvm *kvm, r = check_memory_region_flags(mem); if (r) - goto out; + return r; - r = -EINVAL; as_id = mem->slot >> 16; id = (u16)mem->slot; /* General sanity checks */ if (mem->memory_size & (PAGE_SIZE - 1)) - goto out; + return -EINVAL; if (mem->guest_phys_addr & (PAGE_SIZE - 1)) - goto out; + return -EINVAL; /* We can read the guest memory with __xxx_user() later on. */ if ((id < KVM_USER_MEM_SLOTS) && ((mem->userspace_addr & (PAGE_SIZE - 1)) || !access_ok((void __user *)(unsigned long)mem->userspace_addr, mem->memory_size))) - goto out; + return -EINVAL; if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM) - goto out; + return -EINVAL; if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr) - goto out; + return -EINVAL; slot = id_to_memslot(__kvm_memslots(kvm, as_id), id); base_gfn = mem->guest_phys_addr >> PAGE_SHIFT; npages = mem->memory_size >> PAGE_SHIFT; if (npages > KVM_MEM_MAX_NR_PAGES) - goto out; + return -EINVAL; new = old = *slot; @@ -986,20 +985,18 @@ int __kvm_set_memory_region(struct kvm *kvm, if ((new.userspace_addr != old.userspace_addr) || (npages != old.npages) || ((new.flags ^ old.flags) & KVM_MEM_READONLY)) - goto out; + return -EINVAL; if (base_gfn != old.base_gfn) change = KVM_MR_MOVE; else if (new.flags != old.flags) change = KVM_MR_FLAGS_ONLY; - else { /* Nothing to change. */ - r = 0; - goto out; - } + else /* Nothing to change. */ + return 0; } } else { if (!old.npages) - goto out; + return -EINVAL; change = KVM_MR_DELETE; new.base_gfn = 0; @@ -1008,29 +1005,29 @@ int __kvm_set_memory_region(struct kvm *kvm, if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) { /* Check for overlaps */ - r = -EEXIST; kvm_for_each_memslot(slot, __kvm_memslots(kvm, as_id)) { if (slot->id == id) continue; if (!((base_gfn + npages <= slot->base_gfn) || (base_gfn >= slot->base_gfn + slot->npages))) - goto out; + return -EEXIST; } } - r = -ENOMEM; - /* Allocate/free page dirty bitmap as needed */ if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES)) new.dirty_bitmap = NULL; else if (!new.dirty_bitmap) { - if (kvm_create_dirty_bitmap(&new) < 0) - goto out; + r = kvm_create_dirty_bitmap(&new); + if (r) + return r; } slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT); - if (!slots) + if (!slots) { + r = -ENOMEM; goto out_bitmap; + } memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots)); if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) { @@ -1081,7 +1078,6 @@ int __kvm_set_memory_region(struct kvm *kvm, out_bitmap: if (new.dirty_bitmap && !old.dirty_bitmap) kvm_destroy_dirty_bitmap(&new); -out: return r; } EXPORT_SYMBOL_GPL(__kvm_set_memory_region);