Add stubdomain support. See stubdom/README for usage details.

- Move PAGE_SIZE and STACK_SIZE into __PAGE_SIZE and __STACK_SIZE in
  arch_limits.h so as to permit getting them from there without
  pulling all the internal Mini-OS defines.
- Setup a xen-elf cross-compilation environment in stubdom/cross-root
- Add a POSIX layer on top of Mini-OS by linking against the newlib C
  library and lwIP, and implementing the Unixish part in mini-os/lib/sys.c
- Cross-compile zlib and libpci too.
- Add an xs.h-compatible layer on top of Mini-OS' xenbus.
- Cross-compile libxc with an additional xc_minios.c and a few things
  disabled.
- Cross-compile ioemu with an additional block-vbd, but without sound,
  tpm and other details.  A few hacks are needed:
  - Align ide and scsi buffers at least on sector size to permit
  direct transmission to the block backend. While we are at it, just
  page-align it to possibly save a segment. Also, limit the scsi
  buffer size because of limitations of the block paravirtualization
  protocol.
  - Allocate big tables dynamically rather that letting them go to
  bss: when Mini-OS gets installed in memory, bss is not lazily
  allocated, and doing so during Mini-OS is unnecessarily trick while
  we can simply use malloc.
- Had to change the Mini-OS compilation somehow, so as to export
  Mini-OS compilation flags to the Makefiles of libxc and ioemu.

Signed-off-by: Samuel Thibault <samuel.thibault@eu.citrix.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/extras/mini-os/arch/x86/mm.c b/extras/mini-os/arch/x86/mm.c
index 082527d098..dd556e4741 100644
--- a/extras/mini-os/arch/x86/mm.c
+++ b/extras/mini-os/arch/x86/mm.c
@@ -448,6 +448,15 @@ static unsigned long demand_map_area_start;
 #define DEMAND_MAP_PAGES ((2ULL << 30) / PAGE_SIZE)
 #endif
 
+#ifdef HAVE_LIBC
+unsigned long heap, brk, heap_mapped, heap_end;
+#ifdef __x86_64__
+#define HEAP_PAGES ((128ULL << 30) / PAGE_SIZE)
+#else
+#define HEAP_PAGES ((1ULL << 30) / PAGE_SIZE)
+#endif
+#endif
+
 void arch_init_demand_mapping_area(unsigned long cur_pfn)
 {
     cur_pfn++;
@@ -455,6 +464,14 @@ void arch_init_demand_mapping_area(unsigned long cur_pfn)
     demand_map_area_start = (unsigned long) pfn_to_virt(cur_pfn);
     cur_pfn += DEMAND_MAP_PAGES;
     printk("Demand map pfns at %lx-%lx.\n", demand_map_area_start, pfn_to_virt(cur_pfn));
+
+#ifdef HAVE_LIBC
+    cur_pfn++;
+    heap_mapped = brk = heap = (unsigned long) pfn_to_virt(cur_pfn);
+    cur_pfn += HEAP_PAGES;
+    heap_end = (unsigned long) pfn_to_virt(cur_pfn);
+    printk("Heap resides at %lx-%lx.\n", brk, heap_end);
+#endif
 }
 
 #define MAP_BATCH ((STACK_SIZE / 2) / sizeof(mmu_update_t))