Fix missing DMA32 limit

Rumpdisk needs to allocate dma32 memory areas, so we do always need this
limit.

The non-Xen x86_64 case had a typo, and the 32bit PAE case didn't have
the DMA32 limit.

Also, we have to cope with VM_PAGE_DMA32_LIMIT being either above or below
VM_PAGE_DIRECTMAP_LIMIT depending on the cases.

1 files changed, 19 insertions, 0 deletions

diff --git a/i386/i386at/biosmem.c b/i386/i386at/biosmem.c
index 880989fe..6d0a03ae 100644
--- a/i386/i386at/biosmem.c
+++ b/i386/i386at/biosmem.c
@@ -692,7 +692,9 @@ biosmem_bootstrap_common(void)
     biosmem_set_segment(VM_PAGE_SEG_DMA, phys_start, phys_end);
 
     phys_start = VM_PAGE_DMA_LIMIT;
+
 #ifdef VM_PAGE_DMA32_LIMIT
+#if VM_PAGE_DMA32_LIMIT < VM_PAGE_DIRECTMAP_LIMIT
     phys_end = VM_PAGE_DMA32_LIMIT;
     error = biosmem_map_find_avail(&phys_start, &phys_end);
 
@@ -702,7 +704,9 @@ biosmem_bootstrap_common(void)
     biosmem_set_segment(VM_PAGE_SEG_DMA32, phys_start, phys_end);
 
     phys_start = VM_PAGE_DMA32_LIMIT;
+#endif
 #endif /* VM_PAGE_DMA32_LIMIT */
+
     phys_end = VM_PAGE_DIRECTMAP_LIMIT;
     error = biosmem_map_find_avail(&phys_start, &phys_end);
 
@@ -712,6 +716,21 @@ biosmem_bootstrap_common(void)
     biosmem_set_segment(VM_PAGE_SEG_DIRECTMAP, phys_start, phys_end);
 
     phys_start = VM_PAGE_DIRECTMAP_LIMIT;
+
+#ifdef VM_PAGE_DMA32_LIMIT
+#if VM_PAGE_DMA32_LIMIT > VM_PAGE_DIRECTMAP_LIMIT
+    phys_end = VM_PAGE_DMA32_LIMIT;
+    error = biosmem_map_find_avail(&phys_start, &phys_end);
+
+    if (error)
+        return;
+
+    biosmem_set_segment(VM_PAGE_SEG_DMA32, phys_start, phys_end);
+
+    phys_start = VM_PAGE_DMA32_LIMIT;
+#endif
+#endif /* VM_PAGE_DMA32_LIMIT */
+
     phys_end = VM_PAGE_HIGHMEM_LIMIT;
     error = biosmem_map_find_avail(&phys_start, &phys_end);