From f5fa1569d7e6563e78079e6ad6f10a26319b9a07 Mon Sep 17 00:00:00 2001
From: Stefan Lankes <slankes@eonerc.rwth-aachen.de>
Date: Tue, 15 May 2018 00:54:13 +0200
Subject: [PATCH] reserve larger heap, add gap for pci devices

---
 arch/x86_64/mm/memory.c | 51 +++++++++++++++++++++++++++++++++--------
 include/hermit/stddef.h |  2 +-
 mm/vma.c                |  1 +
 3 files changed, 44 insertions(+), 10 deletions(-)

diff --git a/arch/x86_64/mm/memory.c b/arch/x86_64/mm/memory.c
index 87d21af07..66ae62a12 100644
--- a/arch/x86_64/mm/memory.c
+++ b/arch/x86_64/mm/memory.c
@@ -40,6 +40,9 @@
 #define GAP_BELOW	0x100000ULL
 #define IB_POOL_SIZE 0x400000ULL
 
+#define PCI_GAP_SIZE		(768 << 20)
+#define PCI_GAP_START		((1ULL << 32) - PCI_GAP_SIZE)
+
 extern uint64_t base;
 extern uint64_t limit;
 
@@ -56,7 +59,7 @@ typedef struct free_list {
 extern const void kernel_start;
 
 extern void* host_logical_addr;
-uint64_t ib_pool_addr = 0;
+//uint64_t ib_pool_addr = 0;
 
 static spinlock_irqsave_t list_lock = SPINLOCK_IRQSAVE_INIT;
 
@@ -87,10 +90,14 @@ size_t get_pages(size_t npages)
 			goto out;
 		} else if (i == npages) {
 			ret = curr->start;
-			if (curr->prev)
-				curr->prev = curr->next;
-			else
+			if (curr->prev) { 
+				if (curr->next)
+					curr->next->prev = curr->prev;
+				curr->prev->next = curr->next;
+			} else {
 				free_start = curr->next;
+				free_start->prev = NULL;
+			}
 			if (curr != &init_list)
 				kfree(curr);
 			goto out;
@@ -295,12 +302,19 @@ int memory_init(void)
 			goto oom;
 		}
 	} else {
-		// determine available memory
-		atomic_int64_add(&total_pages, (limit-base) >> PAGE_BITS);
-		atomic_int64_add(&total_available_pages, (limit-base) >> PAGE_BITS);
-
 		init_list.start = PAGE_2M_CEIL(base + image_size);
-		init_list.end = limit;
+
+		if (limit < PCI_GAP_START) {
+			atomic_int64_add(&total_pages, (limit-base) >> PAGE_BITS);
+			atomic_int64_add(&total_available_pages, (limit-base) >> PAGE_BITS);
+
+			init_list.end = limit;
+		} else {
+			atomic_int64_add(&total_pages, (limit-base-PCI_GAP_SIZE) >> PAGE_BITS);
+			atomic_int64_add(&total_available_pages, (limit-base-PCI_GAP_SIZE) >> PAGE_BITS);
+
+			init_list.end = PCI_GAP_START;
+		}
 	}
 
 	// determine allocated memory, we use 2MB pages to map the kernel
@@ -363,6 +377,23 @@ int memory_init(void)
 				}
 			}
 		}
+	} else {
+		// add region after the pci gap
+		if (limit > PCI_GAP_START+PCI_GAP_SIZE) {
+			free_list_t* last = &init_list;
+
+			last->next = kmalloc(sizeof(free_list_t));
+			if (BUILTIN_EXPECT(!last->next, 0))
+				goto oom;
+
+			last->next->prev = last;
+			last = last->next;
+			last->next = NULL;
+			last->start = PCI_GAP_START+PCI_GAP_SIZE;
+			last->end = limit;
+
+			LOG_INFO("Add region 0x%zx - 0x%zx\n", last->start, last->end);
+		}
 	}
 
 	// Ok, we are now able to use our memory management => update tss
@@ -370,6 +401,7 @@ int memory_init(void)
 
 	if (host_logical_addr) {
 		LOG_INFO("Host has its guest logical address at %p\n", host_logical_addr);
+#if 0
 		size_t phyaddr = get_pages(IB_POOL_SIZE >> PAGE_BITS);
 		LOG_INFO("Allocate %d MB at physical address 0x%zx for the IB pool\n", IB_POOL_SIZE >> 20, phyaddr);
 		if (BUILTIN_EXPECT(!page_map((size_t)host_logical_addr+phyaddr, phyaddr, IB_POOL_SIZE >> PAGE_BITS, PG_GLOBAL|PG_RW), 1)) {
@@ -377,6 +409,7 @@ int memory_init(void)
 			ib_pool_addr = (size_t)host_logical_addr+phyaddr;
 			LOG_INFO("Map IB pool at 0x%zx\n", ib_pool_addr);
 		}
+#endif
 	}
 
 	return ret;
diff --git a/include/hermit/stddef.h b/include/hermit/stddef.h
index fc78b8397..c8bd3ac2f 100644
--- a/include/hermit/stddef.h
+++ b/include/hermit/stddef.h
@@ -49,7 +49,7 @@ extern size_t image_size;
 #define CLOCK_TICK_RATE	1193182 /* 8254 chip's internal oscillator frequency */
 #define CACHE_LINE	64
 #define HEAP_START	(PAGE_2M_CEIL(((size_t)&kernel_start + image_size + (16ULL << 10))))
-#define HEAP_SIZE	(1ULL << 32)
+#define HEAP_SIZE	(1ULL << 37)
 #define KMSG_SIZE	0x1000
 #define INT_SYSCALL	0x80
 #define MAILBOX_SIZE	128
diff --git a/mm/vma.c b/mm/vma.c
index ac71b8dc7..fd388222c 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -68,6 +68,7 @@ int vma_init(void)
 	ret = vma_add(HEAP_START, HEAP_START+HEAP_SIZE, VMA_NO_ACCESS);
 	if (BUILTIN_EXPECT(ret, 0))
 		goto out;
+	LOG_INFO("Reserve space for the heap: 0x%llx - 0x%llx\n", HEAP_START, HEAP_START+HEAP_SIZE-1); 
 
 	// we might move the architecture specific VMA regions to a
 	// seperate function vma_arch_init()