Avi Kivity wrote:
> Gerd Hoffmann wrote:
>> Avi Kivity wrote:
>>
>>> We've now switched to allocating guest memory in userspace rather than
>>> in the kernel.
>>>
>> Hmm, a quick glimpse over kvmctl.h doesn't show an obvious way how to
>> use that. If I want to back vm memory with a file mapping, how can I do
>> that?
>>
>
> kvmctl.h doesn't expose an API for that currently, though is should be
> fairly trivial to do so.
Something like this? (compiles, not tested yet).
cheers,
Gerd
* make kvm_create() skip all memory setup in case phys_mem_bytes == 0
* add kvm_register_userspace_phys_mem() to register any userspace memory
as guest physical memory.
Signed-off-by: Gerd Hoffmann <[EMAIL PROTECTED]>
---
user/kvmctl.c | 53 +++++++++++++++++++++++++++++++++++++++++------------
user/kvmctl.h | 3 +++
2 files changed, 44 insertions(+), 12 deletions(-)
Index: kvm-46/user/kvmctl.c
===================================================================
--- kvm-46.orig/user/kvmctl.c
+++ kvm-46/user/kvmctl.c
@@ -443,20 +443,22 @@ int kvm_create(kvm_context_t kvm, unsign
}
kvm->vm_fd = fd;
- r = ioctl(kvm->fd, KVM_CHECK_EXTENSION, KVM_CAP_USER_MEMORY);
- if (r > 0)
- r = kvm_alloc_userspace_memory(kvm, memory, vm_mem);
- else
- r = kvm_alloc_kernel_memory(kvm, memory, vm_mem);
- if (r < 0)
- return r;
+ if (phys_mem_bytes) {
+ r = ioctl(kvm->fd, KVM_CHECK_EXTENSION, KVM_CAP_USER_MEMORY);
+ if (r > 0)
+ r = kvm_alloc_userspace_memory(kvm, memory, vm_mem);
+ else
+ r = kvm_alloc_kernel_memory(kvm, memory, vm_mem);
+ if (r < 0)
+ return r;
- zfd = open("/dev/zero", O_RDONLY);
- mmap(*vm_mem + 0xa8000, 0x8000, PROT_READ|PROT_WRITE,
- MAP_PRIVATE|MAP_FIXED, zfd, 0);
- close(zfd);
+ zfd = open("/dev/zero", O_RDONLY);
+ mmap(*vm_mem + 0xa8000, 0x8000, PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_FIXED, zfd, 0);
+ close(zfd);
- kvm->physical_memory = *vm_mem;
+ kvm->physical_memory = *vm_mem;
+ }
kvm->irqchip_in_kernel = 0;
if (!kvm->no_irqchip_creation) {
@@ -558,6 +560,33 @@ 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)
+{
+ int r;
+ 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,
+ };
+
+ 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
@@ -404,6 +404,9 @@ 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);
-------------------------------------------------------------------------
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/
_______________________________________________
kvm-devel mailing list
kvm-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/kvm-devel
