From fb97665a14c347657e03f07d72098d2c9f76a65d Mon Sep 17 00:00:00 2001
From: cinap_lenrek <cinap_lenrek@felloff.net>
Date: Sun, 1 Jun 2014 06:31:50 +0200
Subject: [PATCH] pc64: use 2MB pages for preallocpages()

---
 sys/src/9/pc64/main.c | 17 +++++++++--------
 sys/src/9/pc64/mem.h  |  1 -
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/sys/src/9/pc64/main.c b/sys/src/9/pc64/main.c
index 8b5b45338..47b5e1c85 100644
--- a/sys/src/9/pc64/main.c
+++ b/sys/src/9/pc64/main.c
@@ -259,7 +259,7 @@ static void
 preallocpages(void)
 {
 	Pallocmem *pm;
-	uintptr va;
+	uintptr va, base, top;
 	vlong size;
 	ulong np;
 	int i;
@@ -272,17 +272,18 @@ preallocpages(void)
 	size = (uvlong)np * BY2PG;
 	size += sizeof(Page) + BY2PG;	/* round up */
 	size = (size / (sizeof(Page) + BY2PG)) * sizeof(Page);
-	size = PGROUND(size);
+	size = ROUND(size, PGLSZ(1));
 
-	np = size/BY2PG;
 	for(i=0; i<nelem(palloc.mem); i++){
 		pm = &palloc.mem[i];
-		if((pm->base + size) <= VMAPSIZE && pm->npage >= np){
-			va = VMAP + pm->base;
-			pmap(m->pml4, pm->base | PTEGLOBAL|PTEWRITE|PTEVALID, va, size);
+		base = ROUND(pm->base, PGLSZ(1));
+		top = pm->base + (uvlong)pm->npage * BY2PG;
+		if((base + size) <= VMAPSIZE && (top - base) >= size){
+			va = base + VMAP;
+			pmap(m->pml4, base | PTEGLOBAL|PTEWRITE|PTEVALID, va, size);
 			palloc.pages = (Page*)va;
-			pm->base += size;
-			pm->npage -= np;
+			pm->base = base + size;
+			pm->npage = (top - pm->base)/BY2PG;
 			break;
 		}
 	}
diff --git a/sys/src/9/pc64/mem.h b/sys/src/9/pc64/mem.h
index 595ade9e3..9ec07363a 100644
--- a/sys/src/9/pc64/mem.h
+++ b/sys/src/9/pc64/mem.h
@@ -22,7 +22,6 @@
 #define	BY2V		8			/* bytes per double word */
 #define	BY2PG		(0x1000ull)		/* bytes per page */
 #define	WD2PG		(BY2PG/BY2WD)		/* words per page */
-#define	BY2XPG		(2*MiB)			/* bytes per big page */
 #define	PGSHIFT		12			/* log(BY2PG) */
 #define	ROUND(s, sz)	(((s)+((sz)-1))&~((sz)-1))
 #define	PGROUND(s)	ROUND(s, BY2PG)