Re: [ÞATCH] kvmtool, mips: Support more than 256 MB guest memory

[Andreas Herrmann <andreas.herrmann@caviumnetworks.com>]

On Wed, Jan 07, 2015 at 05:38:53PM +0800, Chen, Tiejun wrote:
> On 2015/1/6 21:15, Andreas Herrmann wrote:
> >Two guest memory regions need to be defined and two "mem=" parameters
> >need to be passed to guest kernel to support more than 256 MB.
> >
> >Signed-off-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
> >---
> >  tools/kvm/mips/include/kvm/kvm-arch.h |   10 +++++++++
> >  tools/kvm/mips/kvm.c                  |   36 +++++++++++++++++++++++++++------
> >  2 files changed, 40 insertions(+), 6 deletions(-)
> >
> >diff --git a/tools/kvm/mips/include/kvm/kvm-arch.h b/tools/kvm/mips/include/kvm/kvm-arch.h
> >index 7eadbf4..97bbf34 100644
> >--- a/tools/kvm/mips/include/kvm/kvm-arch.h
> >+++ b/tools/kvm/mips/include/kvm/kvm-arch.h
> >@@ -1,10 +1,20 @@
> >  #ifndef KVM__KVM_ARCH_H
> >  #define KVM__KVM_ARCH_H
> >
> >+
> >+/*
> >+ * Guest memory map is:
> >+ *   0x00000000-0x0fffffff : System RAM
> >+ *   0x10000000-0x1fffffff : I/O (defined by KVM_MMIO_START and KVM_MMIO_SIZE)
> >+ *   0x20000000-    ...    : System RAM
> >+ * See also kvm__init_ram().
> >+ */
> >+
> >  #define KVM_MMIO_START		0x10000000
> >  #define KVM_PCI_CFG_AREA	KVM_MMIO_START
> >  #define KVM_PCI_MMIO_AREA	(KVM_MMIO_START + 0x1000000)
> >  #define KVM_VIRTIO_MMIO_AREA	(KVM_MMIO_START + 0x2000000)
> >+#define KVM_MMIO_SIZE		0x10000000
> >
> >  /*
> >   * Just for reference. This and the above corresponds to what's used
> >diff --git a/tools/kvm/mips/kvm.c b/tools/kvm/mips/kvm.c
> >index fc0428b..10b441b 100644
> >--- a/tools/kvm/mips/kvm.c
> >+++ b/tools/kvm/mips/kvm.c
> >@@ -22,11 +22,28 @@ void kvm__init_ram(struct kvm *kvm)
> >  	u64	phys_start, phys_size;
> >  	void	*host_mem;
> >
> >-	phys_start = 0;
> >-	phys_size  = kvm->ram_size;
> >-	host_mem   = kvm->ram_start;
> >+	if (kvm->ram_size <= KVM_MMIO_START) {
> >+		/* one region for all memory */
> >+		phys_start = 0;
> >+		phys_size  = kvm->ram_size;
> >+		host_mem   = kvm->ram_start;
> >
> >-	kvm__register_mem(kvm, phys_start, phys_size, host_mem);
> >+		kvm__register_mem(kvm, phys_start, phys_size, host_mem);
> >+	} else {
> >+		/* one region for memory that fits below MMIO range */
> >+		phys_start = 0;
> >+		phys_size  = KVM_MMIO_SIZE;
> 
> Here phys_size = KVM_MMIO_START is better to make more sense.

Yep, you are right.

> >+		host_mem   = kvm->ram_start;
> >+
> >+		kvm__register_mem(kvm, phys_start, phys_size, host_mem);
> >+
> >+		/* one region for rest of memory */
> >+		phys_start = KVM_MMIO_START + KVM_MMIO_SIZE;
> >+		phys_size  = kvm->ram_size - 0x10000000;
> 
> and, phys_size = kvm->ram_size - KVM_MMIO_START.

Dito.

I'll adapt the patch.


Thanks,

Andreas


> Tiejun
>
> >+		host_mem   = kvm->ram_start + KVM_MMIO_SIZE;
> >+
> >+		kvm__register_mem(kvm, phys_start, phys_size, host_mem);
> >+	}
> >  }
> >
> >  void kvm__arch_delete_ram(struct kvm *kvm)
> >@@ -108,8 +125,15 @@ static void kvm__mips_install_cmdline(struct kvm *kvm)
> >  	u64 argv_offset = argv_start;
> >  	u64 argc = 0;
> >
> >-	sprintf(p + cmdline_offset, "mem=0x%llx@0 ",
> >-		 (unsigned long long)kvm->ram_size);
> >+
> >+	if ((u64) kvm->ram_size <= KVM_MMIO_SIZE)
> >+		sprintf(p + cmdline_offset, "mem=0x%llx@0 ",
> >+			(unsigned long long)kvm->ram_size);
> >+	else
> >+		sprintf(p + cmdline_offset, "mem=0x%llx@0 mem=0x%llx@0x%llx ",
> >+			(unsigned long long)KVM_MMIO_START,
> >+			(unsigned long long)kvm->ram_size - KVM_MMIO_START,
> >+			(unsigned long long)(KVM_MMIO_START + KVM_MMIO_SIZE));
> >
> >  	strcat(p + cmdline_offset, kvm->cfg.real_cmdline); /* maximum size is 2K */
> >
> >