From: Peter Xu <peterx@redhat.com>
To: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: "Paolo Bonzini" <pbonzini@redhat.com>,
"Paul Mackerras" <paulus@ozlabs.org>,
"Christian Borntraeger" <borntraeger@de.ibm.com>,
"Janosch Frank" <frankja@linux.ibm.com>,
"David Hildenbrand" <david@redhat.com>,
"Cornelia Huck" <cohuck@redhat.com>,
"Vitaly Kuznetsov" <vkuznets@redhat.com>,
"Wanpeng Li" <wanpengli@tencent.com>,
"Jim Mattson" <jmattson@google.com>,
"Joerg Roedel" <joro@8bytes.org>, "Marc Zyngier" <maz@kernel.org>,
"James Morse" <james.morse@arm.com>,
"Julien Thierry" <julien.thierry.kdev@gmail.com>,
"Suzuki K Poulose" <suzuki.poulose@arm.com>,
linux-mips@vger.kernel.org, kvm@vger.kernel.org,
kvm-ppc@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org,
"Christoffer Dall" <christoffer.dall@arm.com>,
"Philippe Mathieu-Daudé" <f4bug@amsat.org>
Subject: Re: [PATCH v5 09/19] KVM: Move setting of memslot into helper routine
Date: Thu, 6 Feb 2020 11:26:17 -0500 [thread overview]
Message-ID: <20200206162617.GB695333@xz-x1> (raw)
In-Reply-To: <20200121223157.15263-10-sean.j.christopherson@intel.com>
On Tue, Jan 21, 2020 at 02:31:47PM -0800, Sean Christopherson wrote:
> Split out the core functionality of setting a memslot into a separate
> helper in preparation for moving memslot deletion into its own routine.
>
> Tested-by: Christoffer Dall <christoffer.dall@arm.com>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> ---
> virt/kvm/kvm_main.c | 106 ++++++++++++++++++++++++++------------------
> 1 file changed, 63 insertions(+), 43 deletions(-)
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index fdf045a5d240..64f6c5d35260 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -982,6 +982,66 @@ static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
> return old_memslots;
> }
>
> +static int kvm_set_memslot(struct kvm *kvm,
> + const struct kvm_userspace_memory_region *mem,
> + const struct kvm_memory_slot *old,
> + struct kvm_memory_slot *new, int as_id,
> + enum kvm_mr_change change)
> +{
> + struct kvm_memory_slot *slot;
> + struct kvm_memslots *slots;
> + int r;
> +
> + slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
> + if (!slots)
> + return -ENOMEM;
> + memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots));
> +
> + if (change == KVM_MR_DELETE || change == KVM_MR_MOVE) {
> + /*
> + * Note, the INVALID flag needs to be in the appropriate entry
> + * in the freshly allocated memslots, not in @old or @new.
> + */
> + slot = id_to_memslot(slots, old->id);
> + slot->flags |= KVM_MEMSLOT_INVALID;
> +
> + /*
> + * We can re-use the old memslots, the only difference from the
> + * newly installed memslots is the invalid flag, which will get
> + * dropped by update_memslots anyway. We'll also revert to the
> + * old memslots if preparing the new memory region fails.
> + */
> + slots = install_new_memslots(kvm, as_id, slots);
> +
> + /* From this point no new shadow pages pointing to a deleted,
> + * or moved, memslot will be created.
> + *
> + * validation of sp->gfn happens in:
> + * - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
> + * - kvm_is_visible_gfn (mmu_check_root)
> + */
> + kvm_arch_flush_shadow_memslot(kvm, slot);
> + }
> +
> + r = kvm_arch_prepare_memory_region(kvm, new, mem, change);
> + if (r)
> + goto out_slots;
> +
> + update_memslots(slots, new, change);
> + slots = install_new_memslots(kvm, as_id, slots);
> +
> + kvm_arch_commit_memory_region(kvm, mem, old, new, change);
> +
> + kvfree(slots);
> + return 0;
> +
> +out_slots:
> + if (change == KVM_MR_DELETE || change == KVM_MR_MOVE)
> + slots = install_new_memslots(kvm, as_id, slots);
> + kvfree(slots);
> + return r;
> +}
> +
> /*
> * Allocate some memory and give it an address in the guest physical address
> * space.
> @@ -998,7 +1058,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
> unsigned long npages;
> struct kvm_memory_slot *slot;
> struct kvm_memory_slot old, new;
> - struct kvm_memslots *slots;
> int as_id, id;
> enum kvm_mr_change change;
>
> @@ -1085,58 +1144,19 @@ int __kvm_set_memory_region(struct kvm *kvm,
> return r;
> }
>
> - slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
> - 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)) {
> - slot = id_to_memslot(slots, id);
> - slot->flags |= KVM_MEMSLOT_INVALID;
> -
> - /*
> - * We can re-use the old memslots, the only difference from the
> - * newly installed memslots is the invalid flag, which will get
> - * dropped by update_memslots anyway. We'll also revert to the
> - * old memslots if preparing the new memory region fails.
> - */
> - slots = install_new_memslots(kvm, as_id, slots);
> -
> - /* From this point no new shadow pages pointing to a deleted,
> - * or moved, memslot will be created.
> - *
> - * validation of sp->gfn happens in:
> - * - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
> - * - kvm_is_visible_gfn (mmu_check_root)
> - */
> - kvm_arch_flush_shadow_memslot(kvm, slot);
> - }
> -
> - r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
> - if (r)
> - goto out_slots;
> -
> /* actual memory is freed via old in kvm_free_memslot below */
> if (change == KVM_MR_DELETE) {
> new.dirty_bitmap = NULL;
> memset(&new.arch, 0, sizeof(new.arch));
> }
It's not extremely clear to me on why this single block is leftover
here instead of putting into kvm_set_memslot(). I see that after all
it'll be removed in patch 12, so it seems OK:
Reviewed-by: Peter Xu <peterx@redhat.com>
>
> - update_memslots(slots, &new, change);
> - slots = install_new_memslots(kvm, as_id, slots);
> -
> - kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);
> + r = kvm_set_memslot(kvm, mem, &old, &new, as_id, change);
> + if (r)
> + goto out_bitmap;
>
> kvm_free_memslot(kvm, &old, &new);
> - kvfree(slots);
> return 0;
>
> -out_slots:
> - if (change == KVM_MR_DELETE || change == KVM_MR_MOVE)
> - slots = install_new_memslots(kvm, as_id, slots);
> - kvfree(slots);
> out_bitmap:
> if (new.dirty_bitmap && !old.dirty_bitmap)
> kvm_destroy_dirty_bitmap(&new);
> --
> 2.24.1
>
--
Peter Xu
next prev parent reply other threads:[~2020-02-06 16:26 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-21 22:31 [PATCH v5 00/19] KVM: Dynamically size memslot arrays Sean Christopherson
2020-01-21 22:31 ` [PATCH v5 01/19] KVM: x86: Allocate new rmap and large page tracking when moving memslot Sean Christopherson
2020-02-05 21:49 ` Peter Xu
2020-02-05 23:55 ` Sean Christopherson
2020-02-06 2:00 ` Peter Xu
2020-02-06 2:17 ` Sean Christopherson
2020-02-06 2:58 ` Peter Xu
2020-02-06 5:05 ` Sean Christopherson
2020-01-21 22:31 ` [PATCH v5 02/19] KVM: Reinstall old memslots if arch preparation fails Sean Christopherson
2020-02-05 22:08 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 03/19] KVM: Don't free new memslot if allocation of said memslot fails Sean Christopherson
2020-02-05 22:28 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 04/19] KVM: PPC: Move memslot memory allocation into prepare_memory_region() Sean Christopherson
2020-02-05 22:41 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 05/19] KVM: x86: Allocate memslot resources during prepare_memory_region() Sean Christopherson
2020-01-21 22:31 ` [PATCH v5 06/19] KVM: Drop kvm_arch_create_memslot() Sean Christopherson
2020-02-05 22:45 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 07/19] KVM: Explicitly free allocated-but-unused dirty bitmap Sean Christopherson
2020-01-21 22:31 ` [PATCH v5 08/19] KVM: Refactor error handling for setting memory region Sean Christopherson
2020-02-05 22:48 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 09/19] KVM: Move setting of memslot into helper routine Sean Christopherson
2020-02-06 16:26 ` Peter Xu [this message]
2020-01-21 22:31 ` [PATCH v5 10/19] KVM: Drop "const" attribute from old memslot in commit_memory_region() Sean Christopherson
2020-02-06 16:26 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 11/19] KVM: x86: Free arrays for old memslot when moving memslot's base gfn Sean Christopherson
2020-01-21 22:31 ` [PATCH v5 12/19] KVM: Move memslot deletion to helper function Sean Christopherson
2020-02-06 16:14 ` Peter Xu
2020-02-06 16:28 ` Sean Christopherson
2020-02-06 16:51 ` Peter Xu
2020-02-07 17:59 ` Sean Christopherson
2020-02-07 18:07 ` Sean Christopherson
2020-02-07 18:17 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 13/19] KVM: Simplify kvm_free_memslot() and all its descendents Sean Christopherson
2020-02-06 16:29 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 14/19] KVM: Clean up local variable usage in __kvm_set_memory_region() Sean Christopherson
2020-02-06 19:06 ` Peter Xu
2020-02-06 19:22 ` Sean Christopherson
2020-02-06 19:36 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 15/19] KVM: Provide common implementation for generic dirty log functions Sean Christopherson
2020-02-06 20:02 ` Peter Xu
2020-02-06 21:21 ` Sean Christopherson
2020-02-06 21:41 ` Peter Xu
2020-02-07 19:45 ` Sean Christopherson
2020-02-08 0:18 ` Peter Xu
2020-02-08 0:42 ` Sean Christopherson
2020-02-08 0:53 ` Peter Xu
2020-02-08 1:29 ` Sean Christopherson
2020-02-17 15:39 ` Vitaly Kuznetsov
2020-02-18 17:10 ` Sean Christopherson
2020-02-17 15:35 ` Vitaly Kuznetsov
2020-02-06 21:24 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 16/19] KVM: Ensure validity of memslot with respect to kvm_get_dirty_log() Sean Christopherson
2020-01-21 22:31 ` [PATCH v5 17/19] KVM: Terminate memslot walks via used_slots Sean Christopherson
2020-02-06 21:09 ` Peter Xu
2020-02-07 18:33 ` Sean Christopherson
2020-02-07 20:39 ` Peter Xu
2020-02-07 21:10 ` Sean Christopherson
2020-02-07 21:46 ` Peter Xu
2020-02-07 22:03 ` Sean Christopherson
2020-02-07 22:24 ` Peter Xu
2020-01-21 22:31 ` [PATCH v5 18/19] KVM: Dynamically size memslot array based on number of used slots Sean Christopherson
2020-02-06 22:12 ` Peter Xu
2020-02-07 15:38 ` Sean Christopherson
2020-02-07 16:05 ` Peter Xu
2020-02-07 16:15 ` Sean Christopherson
2020-02-07 16:37 ` Peter Xu
2020-02-07 16:47 ` Sean Christopherson
2020-01-21 22:31 ` [PATCH v5 19/19] KVM: selftests: Add test for KVM_SET_USER_MEMORY_REGION Sean Christopherson
2020-02-06 22:30 ` Peter Xu
2020-02-06 23:11 ` Sean Christopherson
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=20200206162617.GB695333@xz-x1 \
--to=peterx@redhat.com \
--cc=borntraeger@de.ibm.com \
--cc=christoffer.dall@arm.com \
--cc=cohuck@redhat.com \
--cc=david@redhat.com \
--cc=f4bug@amsat.org \
--cc=frankja@linux.ibm.com \
--cc=james.morse@arm.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=julien.thierry.kdev@gmail.com \
--cc=kvm-ppc@vger.kernel.org \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@vger.kernel.org \
--cc=maz@kernel.org \
--cc=paulus@ozlabs.org \
--cc=pbonzini@redhat.com \
--cc=sean.j.christopherson@intel.com \
--cc=suzuki.poulose@arm.com \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.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).