[Qemu-devel] [PATCH QEMU 2/5] kvm: Add two new arch specific functions

[Liang Li <liang.z.li@intel.com>]

Add a new function to get the vm's max pfn and a new function
to filter out the holes to get a tight free page bitmap.
They are implemented on X86, and all the arches should implement
them for live migration optimization.

Signed-off-by: Liang Li <liang.z.li@intel.com>
---
 include/sysemu/kvm.h |  2 ++
 target-arm/kvm.c     | 14 ++++++++++++++
 target-i386/kvm.c    | 35 +++++++++++++++++++++++++++++++++++
 target-mips/kvm.c    | 14 ++++++++++++++
 target-ppc/kvm.c     | 14 ++++++++++++++
 target-s390x/kvm.c   | 14 ++++++++++++++
 6 files changed, 93 insertions(+)

diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index 0e18f15..5263304 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -228,6 +228,8 @@ int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
                           target_ulong len, int type);
 void kvm_remove_all_breakpoints(CPUState *cpu);
 int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap);
+unsigned long *tighten_guest_free_page_bmap(unsigned long *bmap);
+unsigned long get_guest_max_pfn(void);
 #ifndef _WIN32
 int kvm_set_signal_mask(CPUState *cpu, const sigset_t *sigset);
 #endif
diff --git a/target-arm/kvm.c b/target-arm/kvm.c
index 3671032..59e9417 100644
--- a/target-arm/kvm.c
+++ b/target-arm/kvm.c
@@ -626,3 +626,17 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
 {
     return (data - 32) & 0xffff;
 }
+
+unsigned long get_guest_max_pfn(void)
+{
+    /* To be done */
+
+    return 0;
+}
+
+unsigned long *tighten_guest_free_page_bmap(unsigned long *bmap)
+{
+    /* To be done */
+
+    return bmap;
+}
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 799fdfa..76a33bd 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -3334,3 +3334,38 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
 {
     abort();
 }
+
+unsigned long get_guest_max_pfn(void)
+{
+    PCMachineState *pcms = PC_MACHINE(current_machine);
+    ram_addr_t above_4g_mem = pcms->above_4g_mem_size;
+    unsigned long max_pfn;
+
+    if (above_4g_mem) {
+        max_pfn = ((1ULL << 32) + above_4g_mem) >> TARGET_PAGE_BITS;
+    } else {
+        max_pfn = pcms->below_4g_mem_size >> TARGET_PAGE_BITS;
+    }
+
+    return max_pfn;
+}
+
+unsigned long *tighten_guest_free_page_bmap(unsigned long *bmap)
+{
+    PCMachineState *pcms = PC_MACHINE(current_machine);
+    ram_addr_t above_4g_mem = pcms->above_4g_mem_size;
+
+    if (above_4g_mem) {
+        unsigned long *src, *dst, len, pos;
+        ram_addr_t below_4g_mem = pcms->below_4g_mem_size;
+        src = bmap + ((1ULL << 32) >> TARGET_PAGE_BITS) / BITS_PER_LONG;
+        dst = bmap + (below_4g_mem >> TARGET_PAGE_BITS) / BITS_PER_LONG;
+        bitmap_move(dst, src, above_4g_mem >> TARGET_PAGE_BITS);
+
+        pos = (above_4g_mem + below_4g_mem) >> TARGET_PAGE_BITS;
+        len = ((1ULL << 32) - below_4g_mem) >> TARGET_PAGE_BITS;
+        bitmap_clear(bmap, pos, len);
+    }
+
+    return bmap;
+}
diff --git a/target-mips/kvm.c b/target-mips/kvm.c
index 950bc05..23fdc50 100644
--- a/target-mips/kvm.c
+++ b/target-mips/kvm.c
@@ -1048,3 +1048,17 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
 {
     abort();
 }
+
+unsigned long get_guest_max_pfn(void)
+{
+    /* To be done */
+
+    return 0;
+}
+
+unsigned long *tighten_guest_free_page_bmap(unsigned long *bmap)
+{
+    /* To be done */
+
+    return bmap;
+}
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index c4c8146..bf4c60f 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -2579,3 +2579,17 @@ int kvmppc_enable_hwrng(void)
 
     return kvmppc_enable_hcall(kvm_state, H_RANDOM);
 }
+
+unsigned long get_guest_max_pfn(void)
+{
+    /* To be done */
+
+    return 0;
+}
+
+unsigned long *tighten_guest_free_page_bmap(unsigned long *bmap)
+{
+    /* To be done */
+
+    return bmap;
+}
diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index e1859ca..7f5e1b8 100644
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -2250,3 +2250,17 @@ int kvm_arch_msi_data_to_gsi(uint32_t data)
 {
     abort();
 }
+
+unsigned long get_guest_max_pfn(void)
+{
+    /* To be done */
+
+    return 0;
+}
+
+unsigned long *tighten_guest_free_page_bmap(unsigned long *bmap)
+{
+    /* To be done */
+
+    return bmap;
+}
-- 
1.8.3.1