lkml.org 
[lkml]   [2007]   [Dec]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 38/52] KVM: Portability: Split kvm_set_memory_region() to have an arch callout
Date
From: Zhang Xiantao <xiantao.zhang@intel.com>

Moving !user_alloc case to kvm_arch to avoid unnecessary
code logic in non-x86 platform.

Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
---
drivers/kvm/kvm.h | 4 +++
drivers/kvm/kvm_main.c | 38 ++++-------------------------------
drivers/kvm/x86.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 60 insertions(+), 33 deletions(-)
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index c2acd74..49094a2 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -391,6 +391,10 @@ int kvm_set_memory_region(struct kvm *kvm,
int __kvm_set_memory_region(struct kvm *kvm,
struct kvm_userspace_memory_region *mem,
int user_alloc);
+int kvm_arch_set_memory_region(struct kvm *kvm,
+ struct kvm_userspace_memory_region *mem,
+ struct kvm_memory_slot old,
+ int user_alloc);
gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn);
struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn);
void kvm_release_page_clean(struct page *page);
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 6a702e1..5f3ef54 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -291,33 +291,7 @@ int __kvm_set_memory_region(struct kvm *kvm,
memset(new.rmap, 0, npages * sizeof(*new.rmap));

new.user_alloc = user_alloc;
- if (user_alloc)
- new.userspace_addr = mem->userspace_addr;
- else {
- down_write(&current->mm->mmap_sem);
- new.userspace_addr = do_mmap(NULL, 0,
- npages * PAGE_SIZE,
- PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_ANONYMOUS,
- 0);
- up_write(&current->mm->mmap_sem);
-
- if (IS_ERR((void *)new.userspace_addr))
- goto out_free;
- }
- } else {
- if (!old.user_alloc && old.rmap) {
- int ret;
-
- down_write(&current->mm->mmap_sem);
- ret = do_munmap(current->mm, old.userspace_addr,
- old.npages * PAGE_SIZE);
- up_write(&current->mm->mmap_sem);
- if (ret < 0)
- printk(KERN_WARNING
- "kvm_vm_ioctl_set_memory_region: "
- "failed to munmap memory\n");
- }
+ new.userspace_addr = mem->userspace_addr;
}

/* Allocate page dirty bitmap if needed */
@@ -335,14 +309,12 @@ int __kvm_set_memory_region(struct kvm *kvm,

*memslot = new;

- if (!kvm->n_requested_mmu_pages) {
- unsigned int nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm);
- kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages);
+ r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
+ if (r) {
+ *memslot = old;
+ goto out_free;
}

- kvm_mmu_slot_remove_write_access(kvm, mem->slot);
- kvm_flush_remote_tlbs(kvm);
-
kvm_free_physmem_slot(&old, &new);
return 0;

diff --git a/drivers/kvm/x86.c b/drivers/kvm/x86.c
index 5a54e32..6abb2ed 100644
--- a/drivers/kvm/x86.c
+++ b/drivers/kvm/x86.c
@@ -24,6 +24,7 @@
#include <linux/fs.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
+#include <linux/mman.h>

#include <asm/uaccess.h>
#include <asm/msr.h>
@@ -2637,3 +2638,53 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
kvm_free_physmem(kvm);
kfree(kvm);
}
+
+int kvm_arch_set_memory_region(struct kvm *kvm,
+ struct kvm_userspace_memory_region *mem,
+ struct kvm_memory_slot old,
+ int user_alloc)
+{
+ int npages = mem->memory_size >> PAGE_SHIFT;
+ struct kvm_memory_slot *memslot = &kvm->memslots[mem->slot];
+
+ /*To keep backward compatibility with older userspace,
+ *x86 needs to hanlde !user_alloc case.
+ */
+ if (!user_alloc) {
+ if (npages && !old.rmap) {
+ down_write(&current->mm->mmap_sem);
+ memslot->userspace_addr = do_mmap(NULL, 0,
+ npages * PAGE_SIZE,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS,
+ 0);
+ up_write(&current->mm->mmap_sem);
+
+ if (IS_ERR((void *)memslot->userspace_addr))
+ return PTR_ERR((void *)memslot->userspace_addr);
+ } else {
+ if (!old.user_alloc && old.rmap) {
+ int ret;
+
+ down_write(&current->mm->mmap_sem);
+ ret = do_munmap(current->mm, old.userspace_addr,
+ old.npages * PAGE_SIZE);
+ up_write(&current->mm->mmap_sem);
+ if (ret < 0)
+ printk(KERN_WARNING
+ "kvm_vm_ioctl_set_memory_region: "
+ "failed to munmap memory\n");
+ }
+ }
+ }
+
+ if (!kvm->n_requested_mmu_pages) {
+ unsigned int nr_mmu_pages = kvm_mmu_calculate_mmu_pages(kvm);
+ kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages);
+ }
+
+ kvm_mmu_slot_remove_write_access(kvm, mem->slot);
+ kvm_flush_remote_tlbs(kvm);
+
+ return 0;
+}
--
1.5.3.7


\
 
 \ /
  Last update: 2007-12-30 08:31    [from the cache]
©2003-2011 Jasper Spaans