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Message-Id: <20200819151742.7892-5-Eric.VanTassell@amd.com>
Date: Wed, 19 Aug 2020 10:17:42 -0500
From: eric van tassell <Eric.VanTassell@....com>
To: kvm@...r.kernel.org
Cc: linux-kernel@...r.kernel.org, bp@...en8.de, hpa@...or.com,
mingo@...hat.com, jmattson@...gle.com, joro@...tes.org,
pbonzini@...hat.com, sean.j.christopherson@...el.com,
tglx@...utronix.de, vkuznets@...hat.com, wanpengli@...cent.com,
x86@...nel.org, rientjes@...gle.com, junaids@...gle.com,
evantass@....com
Subject: [Patch v2 4/4] KVM:SVM: Remove struct enc_region and associated pinned page tracking.
Remove the enc_region structure definition and the code which maintained
it, as they are no longer needed in view of the xarray support we added in
the previous patch.
Leave svm_register_enc_region() and svm_unregister_enc_region() as stubs
since the ioctl is used by qemu and qemu will crash if they do not
return 0.
Co-developed-by: Brijesh Singh <brijesh.singh@....com>
Signed-off-by: eric van tassell <Eric.VanTassell@....com>
---
arch/x86/kvm/svm/sev.c | 117 +----------------------------------------
arch/x86/kvm/svm/svm.h | 1 -
2 files changed, 1 insertion(+), 117 deletions(-)
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 4a0157254fef..635e15f01edb 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -27,14 +27,6 @@ static unsigned long *sev_asid_bitmap;
static unsigned long *sev_reclaim_asid_bitmap;
#define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT)
-struct enc_region {
- struct list_head list;
- unsigned long npages;
- struct page **pages;
- unsigned long uaddr;
- unsigned long size;
-};
-
static int sev_flush_asids(void)
{
int ret, error = 0;
@@ -182,7 +174,6 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp)
sev->active = true;
sev->asid = asid;
- INIT_LIST_HEAD(&sev->regions_list);
xa_init(&sev->pages_xarray);
@@ -1074,113 +1065,18 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
int svm_register_enc_region(struct kvm *kvm,
struct kvm_enc_region *range)
{
- struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
- struct enc_region *region;
- int ret = 0;
-
- if (!sev_guest(kvm))
- return -ENOTTY;
-
- if (range->addr > ULONG_MAX || range->size > ULONG_MAX)
- return -EINVAL;
-
- region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT);
- if (!region)
- return -ENOMEM;
-
- region->pages = sev_pin_memory(kvm, range->addr, range->size, ®ion->npages, 1);
- if (IS_ERR(region->pages)) {
- ret = PTR_ERR(region->pages);
- goto e_free;
- }
-
- /*
- * The guest may change the memory encryption attribute from C=0 -> C=1
- * or vice versa for this memory range. Lets make sure caches are
- * flushed to ensure that guest data gets written into memory with
- * correct C-bit.
- */
- sev_clflush_pages(region->pages, region->npages);
-
- region->uaddr = range->addr;
- region->size = range->size;
-
- mutex_lock(&kvm->lock);
- list_add_tail(®ion->list, &sev->regions_list);
- mutex_unlock(&kvm->lock);
-
- return ret;
-
-e_free:
- kfree(region);
- return ret;
-}
-
-static struct enc_region *
-find_enc_region(struct kvm *kvm, struct kvm_enc_region *range)
-{
- struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
- struct list_head *head = &sev->regions_list;
- struct enc_region *i;
-
- list_for_each_entry(i, head, list) {
- if (i->uaddr == range->addr &&
- i->size == range->size)
- return i;
- }
-
- return NULL;
-}
-
-static void __unregister_enc_region_locked(struct kvm *kvm,
- struct enc_region *region)
-{
- sev_unpin_memory(kvm, region->pages, region->npages);
- list_del(®ion->list);
- kfree(region);
+ return 0;
}
int svm_unregister_enc_region(struct kvm *kvm,
struct kvm_enc_region *range)
{
- struct enc_region *region;
- int ret;
-
- mutex_lock(&kvm->lock);
-
- if (!sev_guest(kvm)) {
- ret = -ENOTTY;
- goto failed;
- }
-
- region = find_enc_region(kvm, range);
- if (!region) {
- ret = -EINVAL;
- goto failed;
- }
-
- /*
- * Ensure that all guest tagged cache entries are flushed before
- * releasing the pages back to the system for use. CLFLUSH will
- * not do this, so issue a WBINVD.
- */
- wbinvd_on_all_cpus();
-
- __unregister_enc_region_locked(kvm, region);
-
- mutex_unlock(&kvm->lock);
return 0;
-
-failed:
- mutex_unlock(&kvm->lock);
- return ret;
}
void sev_vm_destroy(struct kvm *kvm)
{
struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
- struct list_head *head = &sev->regions_list;
- struct list_head *pos, *q;
XA_STATE(xas, &sev->pages_xarray, 0);
struct page *xa_page;
@@ -1196,17 +1092,6 @@ void sev_vm_destroy(struct kvm *kvm)
*/
wbinvd_on_all_cpus();
- /*
- * if userspace was terminated before unregistering the memory regions
- * then lets unpin all the registered memory.
- */
- if (!list_empty(head)) {
- list_for_each_safe(pos, q, head) {
- __unregister_enc_region_locked(kvm,
- list_entry(pos, struct enc_region, list));
- }
- }
-
/* Release each pinned page that SEV tracked in sev->pages_xarray. */
xas_for_each(&xas, xa_page, ULONG_MAX) {
put_page(xa_page);
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 278c46bc52aa..98d3d7b299cb 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -64,7 +64,6 @@ struct kvm_sev_info {
unsigned int handle; /* SEV firmware handle */
int fd; /* SEV device fd */
unsigned long pages_locked; /* Number of pages locked */
- struct list_head regions_list; /* List of registered regions */
struct xarray pages_xarray; /* List of PFN locked */
};
--
2.17.1
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