[patch] kvmctl.c: allow custom memory setup.

[Gerd Hoffmann <kraxel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

[-- Attachment #1: Type: text/plain, Size: 635 bytes --]

Gerd Hoffmann wrote:
> I've made kvm_create() optionally skip the memory setup, so I can create
> my own later on.  That doesn't work though because creating the vcpu
> fails then.

Ugh, vmx grabs last 4 pages from slot 0 (looks like for real mode
emulation).  Thus memory must exist before creating the vcpu.  Which
makes fitting filemap-backed memory into the current libkvm init
procedure a bit difficuilt.

I've decided to split the kvm_create() into a bunch of pieces which can
be called as needed, so I can first create the vm, then do my custom
memory setup, then create the vcpu without making vmx unhappy ...

cheers,
  Gerd


[-- Attachment #2: kvm-user-memory.diff --]
[-- Type: text/x-patch, Size: 3997 bytes --]

* split kvm_create() into smaller pieces which can be individually
  called if needed.
* add kvm_register_userspace_phys_mem() function.
---
 user/kvmctl.c |   61 +++++++++++++++++++++++++++++++++++++++++++++++++++++-----
 user/kvmctl.h |    8 +++++++
 2 files changed, 64 insertions(+), 5 deletions(-)

Index: kvm-46/user/kvmctl.c
===================================================================
--- kvm-46.orig/user/kvmctl.c
+++ kvm-46/user/kvmctl.c
@@ -427,12 +427,9 @@ int kvm_alloc_userspace_memory(kvm_conte
 	return 0;
 }
 
-int kvm_create(kvm_context_t kvm, unsigned long phys_mem_bytes, void **vm_mem)
+int kvm_create_vm(kvm_context_t kvm)
 {
-	unsigned long memory = (phys_mem_bytes + PAGE_SIZE - 1) & PAGE_MASK;
 	int fd = kvm->fd;
-	int zfd;
-	int r;
 
 	kvm->vcpu_fd[0] = -1;
 
@@ -442,6 +439,15 @@ int kvm_create(kvm_context_t kvm, unsign
 		return -1;
 	}
 	kvm->vm_fd = fd;
+	return 0;
+}
+
+int kvm_create_default_phys_mem(kvm_context_t kvm, unsigned long phys_mem_bytes,
+				void **vm_mem)
+{
+	unsigned long memory = (phys_mem_bytes + PAGE_SIZE - 1) & PAGE_MASK;
+	int zfd;
+	int r;
 
 	r = ioctl(kvm->fd, KVM_CHECK_EXTENSION, KVM_CAP_USER_MEMORY);
 	if (r > 0)
@@ -457,18 +463,37 @@ int kvm_create(kvm_context_t kvm, unsign
         close(zfd);
 
 	kvm->physical_memory = *vm_mem;
+	return 0;
+}
+
+void kvm_create_irqchip(kvm_context_t kvm)
+{
+	int r;
 
 	kvm->irqchip_in_kernel = 0;
 	if (!kvm->no_irqchip_creation) {
 		r = ioctl(kvm->fd, KVM_CHECK_EXTENSION, KVM_CAP_IRQCHIP);
 		if (r > 0) {	/* kernel irqchip supported */
-			r = ioctl(fd, KVM_CREATE_IRQCHIP);
+			r = ioctl(kvm->vm_fd, KVM_CREATE_IRQCHIP);
 			if (r >= 0)
 				kvm->irqchip_in_kernel = 1;
 			else
 				printf("Create kernel PIC irqchip failed\n");
 		}
 	}
+}
+
+int kvm_create(kvm_context_t kvm, unsigned long phys_mem_bytes, void **vm_mem)
+{
+	int r;
+
+	r = kvm_create_vm(kvm);
+	if (r < 0)
+		return r;
+	r = kvm_create_default_phys_mem(kvm, phys_mem_bytes, vm_mem);
+	if (r < 0)
+		return r;
+	kvm_create_irqchip(kvm);
 	r = kvm_create_vcpu(kvm, 0);
 	if (r < 0)
 		return r;
@@ -558,6 +583,32 @@ void *kvm_create_phys_mem(kvm_context_t 
 								log, writable);
 }
 
+int kvm_register_userspace_phys_mem(kvm_context_t kvm,
+			unsigned long phys_start, void *userspace_addr,
+			unsigned long len, int slot, int log)
+{
+	struct kvm_userspace_memory_region memory = {
+		.slot = slot,
+		.memory_size = len,
+		.guest_phys_addr = phys_start,
+		.userspace_addr = (intptr_t)userspace_addr,
+		.flags = log ? KVM_MEM_LOG_DIRTY_PAGES : 0,
+	};
+	int r;
+
+	if (!kvm->physical_memory)
+		kvm->physical_memory = userspace_addr - phys_start;
+
+	r = ioctl(kvm->vm_fd, KVM_SET_USER_MEMORY_REGION, &memory);
+	if (r == -1) {
+		fprintf(stderr, "create_userspace_phys_mem: %s", strerror(errno));
+		return -1;
+	}
+
+	kvm_userspace_memory_region_save_params(kvm, &memory);
+        return 0;
+}
+
 /* destroy/free a whole slot.
  * phys_start, len and slot are the params passed to kvm_create_phys_mem()
  */
Index: kvm-46/user/kvmctl.h
===================================================================
--- kvm-46.orig/user/kvmctl.h
+++ kvm-46/user/kvmctl.h
@@ -137,6 +137,11 @@ int kvm_get_shadow_pages(kvm_context_t k
 int kvm_create(kvm_context_t kvm,
 	       unsigned long phys_mem_bytes,
 	       void **phys_mem);
+int kvm_create_vm(kvm_context_t kvm);
+int kvm_create_default_phys_mem(kvm_context_t kvm, unsigned long phys_mem_bytes,
+				void **vm_mem);
+void kvm_create_irqchip(kvm_context_t kvm);
+
 /*!
  * \brief Create a new virtual cpu
  *
@@ -404,6 +409,9 @@ void *kvm_create_phys_mem(kvm_context_t,
 			  unsigned long len, int slot, int log, int writable);
 void kvm_destroy_phys_mem(kvm_context_t, unsigned long phys_start, 
 			  unsigned long len, int slot);
+int kvm_register_userspace_phys_mem(kvm_context_t kvm,
+			unsigned long phys_start, void *userspace_addr,
+			unsigned long len, int slot, int log);
 int kvm_get_dirty_pages(kvm_context_t, int slot, void *buf);
 
 

[-- Attachment #3: Type: text/plain, Size: 314 bytes --]

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/

[-- Attachment #4: Type: text/plain, Size: 186 bytes --]

_______________________________________________
kvm-devel mailing list
kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
https://lists.sourceforge.net/lists/listinfo/kvm-devel