From: Ben Gardon <bgardon@google.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>,
Sean Christopherson <seanjc@google.com>,
Peter Shier <pshier@google.com>,
Yulei Zhang <yulei.kernel@gmail.com>,
Wanpeng Li <kernellwp@gmail.com>,
Xiao Guangrong <xiaoguangrong.eric@gmail.com>,
Kai Huang <kai.huang@intel.com>,
Keqian Zhu <zhukeqian1@huawei.com>,
Ben Gardon <bgardon@google.com>
Subject: [PATCH v3 3/8] KVM: mmu: Refactor memslot copy
Date: Thu, 6 May 2021 11:42:36 -0700 [thread overview]
Message-ID: <20210506184241.618958-4-bgardon@google.com> (raw)
In-Reply-To: <20210506184241.618958-1-bgardon@google.com>
Factor out copying kvm_memslots from allocating the memory for new ones
in preparation for adding a new lock to protect the arch-specific fields
of the memslots.
No functional change intended.
Signed-off-by: Ben Gardon <bgardon@google.com>
---
virt/kvm/kvm_main.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 2799c6660cce..c8010f55e368 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1306,6 +1306,18 @@ static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
return old_memslots;
}
+static size_t kvm_memslots_size(int slots)
+{
+ return sizeof(struct kvm_memslots) +
+ (sizeof(struct kvm_memory_slot) * slots);
+}
+
+static void kvm_copy_memslots(struct kvm_memslots *from,
+ struct kvm_memslots *to)
+{
+ memcpy(to, from, kvm_memslots_size(from->used_slots));
+}
+
/*
* Note, at a minimum, the current number of used slots must be allocated, even
* when deleting a memslot, as we need a complete duplicate of the memslots for
@@ -1315,19 +1327,16 @@ static struct kvm_memslots *kvm_dup_memslots(struct kvm_memslots *old,
enum kvm_mr_change change)
{
struct kvm_memslots *slots;
- size_t old_size, new_size;
-
- old_size = sizeof(struct kvm_memslots) +
- (sizeof(struct kvm_memory_slot) * old->used_slots);
+ size_t new_size;
if (change == KVM_MR_CREATE)
- new_size = old_size + sizeof(struct kvm_memory_slot);
+ new_size = kvm_memslots_size(old->used_slots + 1);
else
- new_size = old_size;
+ new_size = kvm_memslots_size(old->used_slots);
slots = kvzalloc(new_size, GFP_KERNEL_ACCOUNT);
if (likely(slots))
- memcpy(slots, old, old_size);
+ kvm_copy_memslots(old, slots);
return slots;
}
--
2.31.1.607.g51e8a6a459-goog
next prev parent reply other threads:[~2021-05-06 18:43 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-06 18:42 [PATCH v3 0/8] Lazily allocate memslot rmaps Ben Gardon
2021-05-06 18:42 ` [PATCH v3 1/8] KVM: x86/mmu: Deduplicate rmap freeing Ben Gardon
2021-05-07 7:42 ` David Hildenbrand
2021-05-06 18:42 ` [PATCH v3 2/8] KVM: x86/mmu: Factor out allocating memslot rmap Ben Gardon
2021-05-07 7:46 ` David Hildenbrand
2021-05-10 16:29 ` Ben Gardon
2021-05-06 18:42 ` Ben Gardon [this message]
2021-05-07 7:48 ` [PATCH v3 3/8] KVM: mmu: Refactor memslot copy David Hildenbrand
2021-05-06 18:42 ` [PATCH v3 4/8] KVM: mmu: Add slots_arch_lock for memslot arch fields Ben Gardon
2021-05-06 18:42 ` [PATCH v3 5/8] KVM: x86/mmu: Add a field to control memslot rmap allocation Ben Gardon
2021-05-06 23:44 ` Ben Gardon
2021-05-07 7:50 ` David Hildenbrand
2021-05-07 8:28 ` Paolo Bonzini
2021-05-10 16:14 ` Ben Gardon
2021-05-10 16:33 ` Paolo Bonzini
2021-05-10 16:37 ` Ben Gardon
2021-05-06 18:42 ` [PATCH v3 6/8] KVM: x86/mmu: Skip rmap operations if rmaps not allocated Ben Gardon
2021-05-06 23:07 ` kernel test robot
2021-05-06 18:42 ` [PATCH v3 7/8] KVM: x86/mmu: Protect rmaps independently with SRCU Ben Gardon
2021-05-06 23:58 ` kernel test robot
2021-05-07 0:56 ` kernel test robot
2021-05-07 8:42 ` Paolo Bonzini
2021-05-10 17:45 ` Sean Christopherson
2021-05-10 17:53 ` Paolo Bonzini
2021-05-10 18:28 ` Sean Christopherson
2021-05-11 16:22 ` Ben Gardon
2021-05-11 16:45 ` Paolo Bonzini
2021-05-06 18:42 ` [PATCH v3 8/8] KVM: x86/mmu: Lazily allocate memslot rmaps Ben Gardon
2021-05-07 1:10 ` kernel test robot
2021-05-07 8:28 ` Paolo Bonzini
2021-05-07 7:40 ` [PATCH v3 0/8] " David Hildenbrand
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210506184241.618958-4-bgardon@google.com \
--to=bgardon@google.com \
--cc=kai.huang@intel.com \
--cc=kernellwp@gmail.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=peterx@redhat.com \
--cc=pshier@google.com \
--cc=seanjc@google.com \
--cc=xiaoguangrong.eric@gmail.com \
--cc=yulei.kernel@gmail.com \
--cc=zhukeqian1@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).