[Qemu-devel] [PATCH v3 1/2] spapr: Move RMA memory region registration code

[Alexey Kardashevskiy <aik@ozlabs.ru>]

PPC970 does not support VRMA (virtual RMA) so real memory required
for SLOF to execute must be allocated by the KVM_ALLOCATE_RMA ioctl.
Later this memory is used as a part of the guest RAM area.
The RMA allocating code also registers a memory region for this piece
of RAM.

We are going to simplify memory regions layout: RMA memory region
will be a subregion in the RAM memory region, both starting from zero.
This way we will not have to take care of start address alignment for
the piece of RAM next to the RMA.

This moves memory region business closer to the RAM memory region
creation/allocation code.

As this is a mechanical patch, no change in behaviour is expected.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
 hw/ppc/spapr.c       | 12 +++++++++++-
 target-ppc/kvm.c     | 13 +++----------
 target-ppc/kvm_ppc.h |  2 +-
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 10cbf4d..e182bd5 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1260,6 +1260,8 @@ static void ppc_spapr_init(MachineState *machine)
     int i;
     MemoryRegion *sysmem = get_system_memory();
     MemoryRegion *ram = g_new(MemoryRegion, 1);
+    MemoryRegion *rma_region;
+    void *rma = NULL;
     hwaddr rma_alloc_size;
     hwaddr node0_size = (nb_numa_nodes > 1) ? numa_info[0].node_mem : ram_size;
     uint32_t initrd_base = 0;
@@ -1276,7 +1278,7 @@ static void ppc_spapr_init(MachineState *machine)
     cpu_ppc_hypercall = emulate_spapr_hypercall;
 
     /* Allocate RMA if necessary */
-    rma_alloc_size = kvmppc_alloc_rma("ppc_spapr.rma", sysmem);
+    rma_alloc_size = kvmppc_alloc_rma(&rma);
 
     if (rma_alloc_size == -1) {
         hw_error("qemu: Unable to create RMA\n");
@@ -1379,6 +1381,14 @@ static void ppc_spapr_init(MachineState *machine)
         memory_region_add_subregion(sysmem, nonrma_base, ram);
     }
 
+    if (rma_alloc_size && rma) {
+        rma_region = g_new(MemoryRegion, 1);
+        memory_region_init_ram_ptr(rma_region, NULL, "ppc_spapr.rma",
+                                   rma_alloc_size, rma);
+        vmstate_register_ram_global(rma_region);
+        memory_region_add_subregion(sysmem, 0, rma_region);
+    }
+
     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, "spapr-rtas.bin");
     spapr->rtas_size = load_image_targphys(filename, spapr->rtas_addr,
                                            rtas_limit - spapr->rtas_addr);
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index afc7963..8c9e79c 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -1591,13 +1591,11 @@ int kvmppc_smt_threads(void)
 }
 
 #ifdef TARGET_PPC64
-off_t kvmppc_alloc_rma(const char *name, MemoryRegion *sysmem)
+off_t kvmppc_alloc_rma(void **rma)
 {
-    void *rma;
     off_t size;
     int fd;
     struct kvm_allocate_rma ret;
-    MemoryRegion *rma_region;
 
     /* If cap_ppc_rma == 0, contiguous RMA allocation is not supported
      * if cap_ppc_rma == 1, contiguous RMA allocation is supported, but
@@ -1620,17 +1618,12 @@ off_t kvmppc_alloc_rma(const char *name, MemoryRegion *sysmem)
 
     size = MIN(ret.rma_size, 256ul << 20);
 
-    rma = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
-    if (rma == MAP_FAILED) {
+    *rma = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+    if (*rma == MAP_FAILED) {
         fprintf(stderr, "KVM: Error mapping RMA: %s\n", strerror(errno));
         return -1;
     };
 
-    rma_region = g_new(MemoryRegion, 1);
-    memory_region_init_ram_ptr(rma_region, NULL, name, size, rma);
-    vmstate_register_ram_global(rma_region);
-    memory_region_add_subregion(sysmem, 0, rma_region);
-
     return size;
 }
 
diff --git a/target-ppc/kvm_ppc.h b/target-ppc/kvm_ppc.h
index fad2b8c..5b397cb 100644
--- a/target-ppc/kvm_ppc.h
+++ b/target-ppc/kvm_ppc.h
@@ -33,7 +33,7 @@ int kvmppc_or_tsr_bits(PowerPCCPU *cpu, uint32_t tsr_bits);
 int kvmppc_set_tcr(PowerPCCPU *cpu);
 int kvmppc_booke_watchdog_enable(PowerPCCPU *cpu);
 #ifndef CONFIG_USER_ONLY
-off_t kvmppc_alloc_rma(const char *name, MemoryRegion *sysmem);
+off_t kvmppc_alloc_rma(void **rma);
 bool kvmppc_spapr_use_multitce(void);
 void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t window_size, int *pfd,
                               bool vfio_accel);
-- 
2.0.0