[v4,kvmtool,10/12] arm/arm64: Consolidate RAM initialization in kvm__init_ram()

Commit Message

Alexandru Elisei June 16, 2022, 1:48 p.m. UTC

From: Julien Grall <[e-mail]>

RAM initialization is unnecessarily split between kvm__init_ram() and
kvm__arch_init(). Move all code related to RAM initialization to
kvm__init_ram(), making the code easier to follow and to modify.

One thing to note is that the initialization order is slightly altered:
kvm__arch_enable_mte() and gic__create() are now called before mmap'ing the
guest RAM. That is perfectly fine, as they don't use the host's mapping of
the guest memory.

Reviewed-by: Andre Przywara <[e-mail]>
Signed-off-by: Julien Grall <[e-mail]>
Signed-off-by: Alexandru Elisei <[e-mail]>
---
 arm/kvm.c | 52 ++++++++++++++++++++++++++--------------------------
 1 file changed, 26 insertions(+), 26 deletions(-)

Patch

diff --git a/arm/kvm.c b/arm/kvm.c
index bd44aa350796..abcccfabf59e 100644
--- a/arm/kvm.c
+++ b/arm/kvm.c
@@ -26,9 +26,34 @@  bool kvm__arch_cpu_supports_vm(void)
 
 void kvm__init_ram(struct kvm *kvm)
 {
-	int err;
 	u64 phys_start, phys_size;
 	void *host_mem;
+	int err;
+
+	/*
+	 * Allocate guest memory. We must align our buffer to 64K to
+	 * correlate with the maximum guest page size for virtio-mmio.
+	 * If using THP, then our minimal alignment becomes 2M.
+	 * 2M trumps 64K, so let's go with that.
+	 */
+	kvm->ram_size = kvm->cfg.ram_size;
+	kvm->arch.ram_alloc_size = kvm->ram_size + SZ_2M;
+	kvm->arch.ram_alloc_start = mmap_anon_or_hugetlbfs(kvm,
+						kvm->cfg.hugetlbfs_path,
+						kvm->arch.ram_alloc_size);
+
+	if (kvm->arch.ram_alloc_start == MAP_FAILED)
+		die("Failed to map %lld bytes for guest memory (%d)",
+		    kvm->arch.ram_alloc_size, errno);
+
+	kvm->ram_start = (void *)ALIGN((unsigned long)kvm->arch.ram_alloc_start,
+					SZ_2M);
+
+	madvise(kvm->arch.ram_alloc_start, kvm->arch.ram_alloc_size,
+		MADV_MERGEABLE);
+
+	madvise(kvm->arch.ram_alloc_start, kvm->arch.ram_alloc_size,
+		MADV_HUGEPAGE);
 
 	phys_start	= ARM_MEMORY_AREA;
 	phys_size	= kvm->ram_size;
@@ -59,31 +84,6 @@  void kvm__arch_set_cmdline(char *cmdline, bool video)
 
 void kvm__arch_init(struct kvm *kvm)
 {
-	/*
-	 * Allocate guest memory. We must align our buffer to 64K to
-	 * correlate with the maximum guest page size for virtio-mmio.
-	 * If using THP, then our minimal alignment becomes 2M.
-	 * 2M trumps 64K, so let's go with that.
-	 */
-	kvm->ram_size = kvm->cfg.ram_size;
-	kvm->arch.ram_alloc_size = kvm->ram_size + SZ_2M;
-	kvm->arch.ram_alloc_start = mmap_anon_or_hugetlbfs(kvm,
-						kvm->cfg.hugetlbfs_path,
-						kvm->arch.ram_alloc_size);
-
-	if (kvm->arch.ram_alloc_start == MAP_FAILED)
-		die("Failed to map %lld bytes for guest memory (%d)",
-		    kvm->arch.ram_alloc_size, errno);
-
-	kvm->ram_start = (void *)ALIGN((unsigned long)kvm->arch.ram_alloc_start,
-					SZ_2M);
-
-	madvise(kvm->arch.ram_alloc_start, kvm->arch.ram_alloc_size,
-		MADV_MERGEABLE);
-
-	madvise(kvm->arch.ram_alloc_start, kvm->arch.ram_alloc_size,
-		MADV_HUGEPAGE);
-
 	/* Create the virtual GIC. */
 	if (gic__create(kvm, kvm->cfg.arch.irqchip))
 		die("Failed to create virtual GIC");