From patchwork Fri Nov 22 19:12:44 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Williamson X-Patchwork-Id: 293580 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id B7B0F2C007A for ; Sat, 23 Nov 2013 06:13:22 +1100 (EST) Received: from localhost ([::1]:40643 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VjwAI-00056B-FV for incoming@patchwork.ozlabs.org; Fri, 22 Nov 2013 14:13:18 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46554) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vjw9s-00055t-PD for qemu-devel@nongnu.org; Fri, 22 Nov 2013 14:12:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Vjw9m-00024f-Oj for qemu-devel@nongnu.org; Fri, 22 Nov 2013 14:12:52 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60021) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Vjw9m-00024b-Gj for qemu-devel@nongnu.org; Fri, 22 Nov 2013 14:12:46 -0500 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id rAMJCjc9005926 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 22 Nov 2013 14:12:45 -0500 Received: from bling.home (ovpn-113-87.phx2.redhat.com [10.3.113.87]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id rAMJCiUb009574; Fri, 22 Nov 2013 14:12:44 -0500 To: pbonzini@redhat.com, gleb@redhat.com, kvm@vger.kernel.org From: Alex Williamson Date: Fri, 22 Nov 2013 12:12:44 -0700 Message-ID: <20131122191154.16705.42189.stgit@bling.home> User-Agent: StGit/0.16 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.67 on 10.5.11.12 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH] kvm: Query KVM for available memory slots X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org KVM reports the number of available memory slots (KVM_CAP_NR_MEMSLOTS) using the extension interface. Both x86 and s390 implement this, ARM and powerpc do not yet enable it. Convert the static slots array to be dynamically allocated, supporting more slots when available. Default to 32 when KVM_CAP_NR_MEMSLOTS is not implemented. The motivation for this change is to support more assigned devices, where memory mapped PCI MMIO BARs typically take one slot each. Signed-off-by: Alex Williamson Reviewed-by: Thomas Huth --- kvm-all.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/kvm-all.c b/kvm-all.c index 4478969..63c4e9b 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -72,7 +72,8 @@ typedef struct kvm_dirty_log KVMDirtyLog; struct KVMState { - KVMSlot slots[32]; + KVMSlot *slots; + int nr_slots; int fd; int vmfd; int coalesced_mmio; @@ -125,7 +126,7 @@ static KVMSlot *kvm_alloc_slot(KVMState *s) { int i; - for (i = 0; i < ARRAY_SIZE(s->slots); i++) { + for (i = 0; i < s->nr_slots; i++) { if (s->slots[i].memory_size == 0) { return &s->slots[i]; } @@ -141,7 +142,7 @@ static KVMSlot *kvm_lookup_matching_slot(KVMState *s, { int i; - for (i = 0; i < ARRAY_SIZE(s->slots); i++) { + for (i = 0; i < s->nr_slots; i++) { KVMSlot *mem = &s->slots[i]; if (start_addr == mem->start_addr && @@ -163,7 +164,7 @@ static KVMSlot *kvm_lookup_overlapping_slot(KVMState *s, KVMSlot *found = NULL; int i; - for (i = 0; i < ARRAY_SIZE(s->slots); i++) { + for (i = 0; i < s->nr_slots; i++) { KVMSlot *mem = &s->slots[i]; if (mem->memory_size == 0 || @@ -185,7 +186,7 @@ int kvm_physical_memory_addr_from_host(KVMState *s, void *ram, { int i; - for (i = 0; i < ARRAY_SIZE(s->slots); i++) { + for (i = 0; i < s->nr_slots; i++) { KVMSlot *mem = &s->slots[i]; if (ram >= mem->ram && ram < mem->ram + mem->memory_size) { @@ -357,7 +358,7 @@ static int kvm_set_migration_log(int enable) s->migration_log = enable; - for (i = 0; i < ARRAY_SIZE(s->slots); i++) { + for (i = 0; i < s->nr_slots; i++) { mem = &s->slots[i]; if (!mem->memory_size) { @@ -1383,9 +1384,6 @@ int kvm_init(void) #ifdef KVM_CAP_SET_GUEST_DEBUG QTAILQ_INIT(&s->kvm_sw_breakpoints); #endif - for (i = 0; i < ARRAY_SIZE(s->slots); i++) { - s->slots[i].slot = i; - } s->vmfd = -1; s->fd = qemu_open("/dev/kvm", O_RDWR); if (s->fd == -1) { @@ -1409,6 +1407,19 @@ int kvm_init(void) goto err; } + s->nr_slots = kvm_check_extension(s, KVM_CAP_NR_MEMSLOTS); + + /* If unspecified, use the previous default value */ + if (!s->nr_slots) { + s->nr_slots = 32; + } + + s->slots = g_malloc0(s->nr_slots * sizeof(KVMSlot)); + + for (i = 0; i < s->nr_slots; i++) { + s->slots[i].slot = i; + } + /* check the vcpu limits */ soft_vcpus_limit = kvm_recommended_vcpus(s); hard_vcpus_limit = kvm_max_vcpus(s); @@ -1527,6 +1538,7 @@ err: if (s->fd != -1) { close(s->fd); } + g_free(s->slots); g_free(s); return ret;