[RFC PATCH 1/1] Add pci_hole_min_size

[Don Slutz <dslutz@verizon.com>]

This allows growing the pci_hole to the size needed.

Signed-off-by: Don Slutz <dslutz@verizon.com>
---
 tools/firmware/hvmloader/pci.c | 10 ++++++++++
 tools/libxc/xc_hvm_build_x86.c | 22 ++++++++++++++++++++++
 tools/libxc/xenguest.h         | 11 +++++++++++
 tools/libxl/libxl_create.c     |  4 +++-
 tools/libxl/libxl_dm.c         | 13 +++++++++++--
 tools/libxl/libxl_dom.c        |  3 ++-
 tools/libxl/libxl_types.idl    |  1 +
 tools/libxl/xl_cmdimpl.c       |  6 ++++++
 8 files changed, 66 insertions(+), 4 deletions(-)

diff --git a/tools/firmware/hvmloader/pci.c b/tools/firmware/hvmloader/pci.c
index 627e8cb..b36d00b 100644
--- a/tools/firmware/hvmloader/pci.c
+++ b/tools/firmware/hvmloader/pci.c
@@ -58,6 +58,7 @@ void pci_setup(void)
         uint64_t bar_sz;
     } *bars = (struct bars *)scratch_start;
     unsigned int i, nr_bars = 0;
+    uint64_t pci_hole_min_size;
 
     const char *s;
     /*
@@ -85,6 +86,9 @@ void pci_setup(void)
     printf("Relocating guest memory for lowmem MMIO space %s\n",
            allow_memory_relocate?"enabled":"disabled");
 
+    s = xenstore_read("platform/pci_hole_min_size", "0");
+    pci_hole_min_size = strtoll(s, NULL, 0);
+
     /* Program PCI-ISA bridge with appropriate link routes. */
     isa_irq = 0;
     for ( link = 0; link < 4; link++ )
@@ -236,6 +240,12 @@ void pci_setup(void)
         pci_writew(devfn, PCI_COMMAND, cmd);
     }
 
+    if (pci_hole_min_size) {
+        pci_mem_start = (1ull << 32) - pci_hole_min_size;
+        printf("pci_mem_start=0x%lx (was 0x%x) for pci_hole_min_size=%llu\n",
+               pci_mem_start, PCI_MEM_START, pci_hole_min_size);
+    }
+
     /*
      * At the moment qemu-xen can't deal with relocated memory regions.
      * It's too close to the release to make a proper fix; for now,
diff --git a/tools/libxc/xc_hvm_build_x86.c b/tools/libxc/xc_hvm_build_x86.c
index dd3b522..4752d58 100644
--- a/tools/libxc/xc_hvm_build_x86.c
+++ b/tools/libxc/xc_hvm_build_x86.c
@@ -603,16 +603,38 @@ int xc_hvm_build_target_mem(xc_interface *xch,
                            int target,
                            const char *image_name)
 {
+    return xc_hvm_build_target_mem_with_hole(xch, domid, memsize, target, image_name, 0);
+}
+
+int xc_hvm_build_target_mem_with_hole(xc_interface *xch,
+                                      uint32_t domid,
+                                      int memsize,
+                                      int target,
+                                      const char *image_name,
+                                      uint64_t pci_hole_min_size)
+{
     struct xc_hvm_build_args args = {};
 
     memset(&args, 0, sizeof(struct xc_hvm_build_args));
     args.mem_size = (uint64_t)memsize << 20;
     args.mem_target = (uint64_t)target << 20;
     args.image_file_name = image_name;
+    if (pci_hole_min_size > HVM_BELOW_4G_MMIO_LENGTH)
+        args.mmio_size = pci_hole_min_size;
 
     return xc_hvm_build(xch, domid, &args);
 }
 
+int xc_hvm_build_with_hole(xc_interface *xch, uint32_t domid,
+                           struct xc_hvm_build_args *args,
+                           uint64_t pci_hole_min_size)
+{
+    if (pci_hole_min_size > HVM_BELOW_4G_MMIO_LENGTH)
+        args->mmio_size = pci_hole_min_size;
+
+    return xc_hvm_build(xch, domid, args);
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/tools/libxc/xenguest.h b/tools/libxc/xenguest.h
index a0e30e1..44290bd 100644
--- a/tools/libxc/xenguest.h
+++ b/tools/libxc/xenguest.h
@@ -248,12 +248,23 @@ struct xc_hvm_build_args {
 int xc_hvm_build(xc_interface *xch, uint32_t domid,
                  struct xc_hvm_build_args *hvm_args);
 
+int xc_hvm_build_with_hole(xc_interface *xch, uint32_t domid,
+                           struct xc_hvm_build_args *args,
+                           uint64_t pci_hole_min_size);
+
 int xc_hvm_build_target_mem(xc_interface *xch,
                             uint32_t domid,
                             int memsize,
                             int target,
                             const char *image_name);
 
+int xc_hvm_build_target_mem_with_hole(xc_interface *xch,
+                                      uint32_t domid,
+                                      int memsize,
+                                      int target,
+                                      const char *image_name,
+                                      uint64_t pci_hole_min_size);
+
 int xc_suspend_evtchn_release(xc_interface *xch, xc_evtchn *xce, int domid, int suspend_evtchn);
 
 int xc_suspend_evtchn_init(xc_interface *xch, xc_evtchn *xce, int domid, int port);
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index a604cd8..24ceac6 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -388,13 +388,15 @@ int libxl__domain_build(libxl__gc *gc,
         vments[4] = "start_time";
         vments[5] = libxl__sprintf(gc, "%lu.%02d", start_time.tv_sec,(int)start_time.tv_usec/10000);
 
-        localents = libxl__calloc(gc, 7, sizeof(char *));
+        localents = libxl__calloc(gc, 9, sizeof(char *));
         localents[0] = "platform/acpi";
         localents[1] = libxl_defbool_val(info->u.hvm.acpi) ? "1" : "0";
         localents[2] = "platform/acpi_s3";
         localents[3] = libxl_defbool_val(info->u.hvm.acpi_s3) ? "1" : "0";
         localents[4] = "platform/acpi_s4";
         localents[5] = libxl_defbool_val(info->u.hvm.acpi_s4) ? "1" : "0";
+        localents[6] = "platform/pci_hole_min_size";
+        localents[7] = libxl__sprintf(gc, "%llu", (unsigned long long)info->u.hvm.pci_hole_min_size);
 
         break;
     case LIBXL_DOMAIN_TYPE_PV:
diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
index f6f7bbd..66ba7cd 100644
--- a/tools/libxl/libxl_dm.c
+++ b/tools/libxl/libxl_dm.c
@@ -653,17 +653,26 @@ static char ** libxl__build_device_model_args_new(libxl__gc *gc,
             flexarray_append(dm_args, b_info->extra_pv[i]);
         break;
     case LIBXL_DOMAIN_TYPE_HVM:
+    {
+        char *machinearg;
+
         if (!libxl_defbool_val(b_info->u.hvm.xen_platform_pci)) {
             /* Switching here to the machine "pc" which does not add
              * the xen-platform device instead of the default "xenfv" machine.
              */
-            flexarray_append(dm_args, "pc,accel=xen");
+            machinearg = libxl__sprintf(gc, "pc,accel=xen");
         } else {
-            flexarray_append(dm_args, "xenfv");
+            machinearg = libxl__sprintf(gc, "xenfv");
+        }
+        if (b_info->u.hvm.pci_hole_min_size) {
+            machinearg = libxl__sprintf(gc, "%s,pci_hole_min_size=%llu", machinearg,
+                            (unsigned long long) b_info->u.hvm.pci_hole_min_size);
         }
+        flexarray_append(dm_args, machinearg);
         for (i = 0; b_info->extra_hvm && b_info->extra_hvm[i] != NULL; i++)
             flexarray_append(dm_args, b_info->extra_hvm[i]);
         break;
+    }
     default:
         abort();
     }
diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c
index 55f74b2..6ebc606 100644
--- a/tools/libxl/libxl_dom.c
+++ b/tools/libxl/libxl_dom.c
@@ -642,7 +642,8 @@ int libxl__build_hvm(libxl__gc *gc, uint32_t domid,
         goto out;
     }
 
-    ret = xc_hvm_build(ctx->xch, domid, &args);
+    ret = xc_hvm_build_with_hole(ctx->xch, domid, &args,
+                                 info->u.hvm.pci_hole_min_size);
     if (ret) {
         LOGEV(ERROR, ret, "hvm building failed");
         goto out;
diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
index 649ce50..febfbb4 100644
--- a/tools/libxl/libxl_types.idl
+++ b/tools/libxl/libxl_types.idl
@@ -346,6 +346,7 @@ libxl_domain_build_info = Struct("domain_build_info",[
                                        ("timeoffset",       string),
                                        ("hpet",             libxl_defbool),
                                        ("vpt_align",        libxl_defbool),
+                                       ("pci_hole_min_size",uint64),
                                        ("timer_mode",       libxl_timer_mode),
                                        ("nested_hvm",       libxl_defbool),
                                        ("smbios_firmware",  string),
diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
index 4fc46eb..fe247ee 100644
--- a/tools/libxl/xl_cmdimpl.c
+++ b/tools/libxl/xl_cmdimpl.c
@@ -1025,6 +1025,12 @@ static void parse_config_data(const char *config_source,
         xlu_cfg_get_defbool(config, "hpet", &b_info->u.hvm.hpet, 0);
         xlu_cfg_get_defbool(config, "vpt_align", &b_info->u.hvm.vpt_align, 0);
 
+        if (!xlu_cfg_get_long(config, "pci_hole_min_size", &l, 0)) {
+            b_info->u.hvm.pci_hole_min_size = (uint64_t) l;
+            if (dom_info->debug)
+                fprintf(stderr, "pci_hole_min_size: %llu\n", (unsigned long long) b_info->u.hvm.pci_hole_min_size);
+        }
+
         if (!xlu_cfg_get_long(config, "timer_mode", &l, 1)) {
             const char *s = libxl_timer_mode_to_string(l);
             fprintf(stderr, "WARNING: specifying \"timer_mode\" as an integer is deprecated. "
-- 
1.8.4