Re: uvm physseg - put the lid on it.

>>>>> "Cherry" == Cherry G Mathew <[email protected]> writes:

    Cherry> Hi Everyone, Here's a patch to put the vm physseg stuff
    Cherry> behind bars.

Hi,

The previous patch had spurious whitespace and other noise in it, which
I'm very sorry for.

Here's a (hopefully) cleaner one. I've compile tested it on amd64.

-- 
~cherry

Index: sys/arch/amd64/amd64/machdep.c
===================================================================
RCS file: /cvsroot/src/sys/arch/amd64/amd64/machdep.c,v
retrieving revision 1.230
diff -u -r1.230 machdep.c
--- sys/arch/amd64/amd64/machdep.c	27 Aug 2016 16:17:16 -0000	1.230
+++ sys/arch/amd64/amd64/machdep.c	28 Sep 2016 12:00:42 -0000
@@ -799,10 +799,23 @@
 			setbit(sparse_dump_physmap, p);
 		}
 	}
-	for (i = 0; i < vm_nphysseg; i++) {
-		struct vm_physseg *seg = VM_PHYSMEM_PTR(i);
+        for (i = 0; i < VM_PHYSSEG_MAX; i++) {
+		paddr_t pfn;
 
-		for (pg = seg->pgs; pg < seg->lastpg; pg++) {
+		if (uvm_physmem_valid(i) == false)
+			break;
+
+		const paddr_t startpfn = uvm_physmem_get_start(i);
+		const paddr_t endpfn = uvm_physmem_get_end(i);
+
+		KASSERT(startpfn != -1 && endpfn != -1);
+
+		/*
+		 * We assume that seg->start to seg->end are
+		 * uvm_page_physload()ed
+		 */
+		for (pfn = startpfn; pfn <= endpfn; pfn++) {
+			pg = PHYS_TO_VM_PAGE(ptoa(pfn));
 			if (pg->uanon || (pg->pqflags & PQ_FREE) ||
 			    (pg->uobject && pg->uobject->pgops)) {
 				p = VM_PAGE_TO_PHYS(pg) / PAGE_SIZE;
@@ -1445,56 +1458,29 @@
 init_x86_64_msgbuf(void)
 {
 	/* Message buffer is located at end of core. */
-	struct vm_physseg *vps;
-	psize_t sz = round_page(MSGBUFSIZE);
-	psize_t reqsz = sz;
-	int x;
+	psize_t reqsz = round_page(MSGBUFSIZE);
+	psize_t sz = 0;
 		
- search_again:
-	vps = NULL;
+	for (sz = 0; sz < reqsz; sz += PAGE_SIZE) {
+		paddr_t stolenpa;
 
-	for (x = 0; x < vm_nphysseg; x++) {
-		vps = VM_PHYSMEM_PTR(x);
-		if (ctob(vps->avail_end) == avail_end)
+		if (!uvm_page_physget(&stolenpa))
 			break;
-	}
-	if (x == vm_nphysseg)
-		panic("init_x86_64: can't find end of memory");
-
-	/* Shrink so it'll fit in the last segment. */
-	if ((vps->avail_end - vps->avail_start) < atop(sz))
-		sz = ctob(vps->avail_end - vps->avail_start);
-
-	vps->avail_end -= atop(sz);
-	vps->end -= atop(sz);
-            msgbuf_p_seg[msgbuf_p_cnt].sz = sz;
-            msgbuf_p_seg[msgbuf_p_cnt++].paddr = ctob(vps->avail_end);
-
-	/* Remove the last segment if it now has no pages. */
-	if (vps->start == vps->end) {
-		for (vm_nphysseg--; x < vm_nphysseg; x++)
-			VM_PHYSMEM_PTR_SWAP(x, x + 1);
-	}
-
-	/* Now find where the new avail_end is. */
-	for (avail_end = 0, x = 0; x < vm_nphysseg; x++)
-		if (VM_PHYSMEM_PTR(x)->avail_end > avail_end)
-			avail_end = VM_PHYSMEM_PTR(x)->avail_end;
-	avail_end = ctob(avail_end);
-
-	if (sz == reqsz)
-		return;
 
-	reqsz -= sz;
-	if (msgbuf_p_cnt == VM_PHYSSEG_MAX) {
-		/* No more segments available, bail out. */
-		printf("WARNING: MSGBUFSIZE (%zu) too large, using %zu.\n",
-		    (size_t)MSGBUFSIZE, (size_t)(MSGBUFSIZE - reqsz));
-		return;
+		if (stolenpa == (msgbuf_p_seg[msgbuf_p_cnt].paddr
+			+ PAGE_SIZE)) {
+			/* contiguous: append it to current buf alloc */
+			msgbuf_p_seg[msgbuf_p_cnt].sz += PAGE_SIZE;
+		} else  {
+			/* non-contiguous: start a new msgbuf seg */
+			msgbuf_p_seg[msgbuf_p_cnt].sz = PAGE_SIZE;
+			msgbuf_p_seg[msgbuf_p_cnt++].paddr = stolenpa;
+	}
 	}
 
-	sz = reqsz;
-	goto search_again;
+	if (sz != reqsz)
+		printf("%s: could only allocate %ld bytes of requested %ld bytes\n",
+		    __func__, sz, reqsz);
 }
 
 static void
Index: sys/arch/i386/i386/machdep.c
===================================================================
RCS file: /cvsroot/src/sys/arch/i386/i386/machdep.c,v
retrieving revision 1.761
diff -u -r1.761 machdep.c
--- sys/arch/i386/i386/machdep.c	27 Aug 2016 16:07:26 -0000	1.761
+++ sys/arch/i386/i386/machdep.c	28 Sep 2016 12:00:50 -0000
@@ -1032,56 +1032,29 @@
 init386_msgbuf(void)
 {
 	/* Message buffer is located at end of core. */
-	struct vm_physseg *vps;
-	psize_t sz = round_page(MSGBUFSIZE);
-	psize_t reqsz = sz;
-	unsigned int x;
-
- search_again:
-	vps = NULL;
-	for (x = 0; x < vm_nphysseg; ++x) {
-		vps = VM_PHYSMEM_PTR(x);
-		if (ctob(vps->avail_end) == avail_end) {
-			break;
-		}
-	}
-	if (x == vm_nphysseg)
-		panic("init386: can't find end of memory");
+	psize_t reqsz = round_page(MSGBUFSIZE);
+	psize_t sz = 0;
 
-	/* Shrink so it'll fit in the last segment. */
-	if (vps->avail_end - vps->avail_start < atop(sz))
-		sz = ctob(vps->avail_end - vps->avail_start);
-
-	vps->avail_end -= atop(sz);
-	vps->end -= atop(sz);
-	msgbuf_p_seg[msgbuf_p_cnt].sz = sz;
-	msgbuf_p_seg[msgbuf_p_cnt++].paddr = ctob(vps->avail_end);
-
-	/* Remove the last segment if it now has no pages. */
-	if (vps->start == vps->end) {
-		for (--vm_nphysseg; x < vm_nphysseg; x++)
-			VM_PHYSMEM_PTR_SWAP(x, x + 1);
-	}
-
-	/* Now find where the new avail_end is. */
-	for (avail_end = 0, x = 0; x < vm_nphysseg; x++)
-		if (VM_PHYSMEM_PTR(x)->avail_end > avail_end)
-			avail_end = VM_PHYSMEM_PTR(x)->avail_end;
-	avail_end = ctob(avail_end);
+	for (sz = 0; sz < reqsz; sz += PAGE_SIZE) {
+		paddr_t stolenpa;
 
-	if (sz == reqsz)
-		return;
+		if (!uvm_page_physget(&stolenpa))
+			break;
 
-	reqsz -= sz;
-	if (msgbuf_p_cnt == VM_PHYSSEG_MAX) {
-		/* No more segments available, bail out. */
-		printf("WARNING: MSGBUFSIZE (%zu) too large, using %zu.\n",
-		    (size_t)MSGBUFSIZE, (size_t)(MSGBUFSIZE - reqsz));
-		return;
+		if (stolenpa == (msgbuf_p_seg[msgbuf_p_cnt].paddr
+			+ PAGE_SIZE)) {
+			/* contiguous: append it to current buf alloc */
+			msgbuf_p_seg[msgbuf_p_cnt].sz += PAGE_SIZE;
+		} else  {
+			/* non-contiguous: start a new msgbuf seg */
+			msgbuf_p_seg[msgbuf_p_cnt].sz = PAGE_SIZE;
+			msgbuf_p_seg[msgbuf_p_cnt++].paddr = stolenpa;
+	}
 	}
 
-	sz = reqsz;
-	goto search_again;
+	if (sz != reqsz)
+		printf("%s: could only allocate %ld bytes of requested %ld bytes\n",
+		    __func__, sz, reqsz);
 }
 
 #ifndef XEN
Index: sys/arch/x86/x86/x86_machdep.c
===================================================================
RCS file: /cvsroot/src/sys/arch/x86/x86/x86_machdep.c,v
retrieving revision 1.75
diff -u -r1.75 x86_machdep.c
--- sys/arch/x86/x86/x86_machdep.c	1 Aug 2016 16:07:39 -0000	1.75
+++ sys/arch/x86/x86/x86_machdep.c	28 Sep 2016 12:00:56 -0000
@@ -67,6 +67,7 @@
 #include <machine/vmparam.h>
 
 #include <uvm/uvm_extern.h>
+#include <uvm/uvm_physmem.h>
 
 #include "acpica.h"
 #if NACPICA > 0
Index: sys/sys/systm.h
===================================================================
RCS file: /cvsroot/src/sys/sys/systm.h,v
retrieving revision 1.271
diff -u -r1.271 systm.h
--- sys/sys/systm.h	6 Jul 2016 05:20:48 -0000	1.271
+++ sys/sys/systm.h	28 Sep 2016 12:01:10 -0000
@@ -82,7 +82,7 @@
 extern int selwait;		/* select timeout address */
 
 extern int maxmem;		/* max memory per process */
-extern int physmem;		/* physical memory */
+extern psize_t physmem;		/* physical memory */
 
 extern dev_t dumpdev;		/* dump device */
 extern dev_t dumpcdev;		/* dump device (character equivalent) */
Index: sys/uvm/Makefile
===================================================================
RCS file: /cvsroot/src/sys/uvm/Makefile,v
retrieving revision 1.9
diff -u -r1.9 Makefile
--- sys/uvm/Makefile	11 Feb 2006 12:45:07 -0000	1.9
+++ sys/uvm/Makefile	28 Sep 2016 12:01:10 -0000
@@ -5,7 +5,7 @@
 INCS=	uvm.h uvm_amap.h uvm_anon.h uvm_aobj.h uvm_device.h \
 	uvm_extern.h uvm_fault.h uvm_fault_i.h uvm_glue.h \
 	uvm_km.h uvm_loan.h \
-	uvm_map.h uvm_object.h uvm_page.h \
+	uvm_map.h uvm_object.h uvm_page.h uvm_physmem.h \
 	uvm_pager.h uvm_param.h uvm_pdaemon.h uvm_pglist.h \
 	uvm_pmap.h uvm_prot.h uvm_stat.h \
 	uvm_swap.h
Index: sys/uvm/files.uvm
===================================================================
RCS file: /cvsroot/src/sys/uvm/files.uvm,v
retrieving revision 1.26
diff -u -r1.26 files.uvm
--- sys/uvm/files.uvm	12 Aug 2016 13:40:21 -0000	1.26
+++ sys/uvm/files.uvm	28 Sep 2016 12:01:10 -0000
@@ -41,6 +41,7 @@
 file	uvm/uvm_pdpolicy_clock.c	!pdpolicy_clockpro
 file	uvm/uvm_pdpolicy_clockpro.c	pdpolicy_clockpro
 file	uvm/uvm_pglist.c		uvm
+file	uvm/uvm_physmem.c		uvm
 file	uvm/uvm_readahead.c		uvm
 file	uvm/uvm_stat.c                	uvm
 file	uvm/uvm_swap.c			vmswap
Index: sys/uvm/uvm.h
===================================================================
RCS file: /cvsroot/src/sys/uvm/uvm.h,v
retrieving revision 1.66
diff -u -r1.66 uvm.h
--- sys/uvm/uvm.h	13 Apr 2015 22:04:44 -0000	1.66
+++ sys/uvm/uvm.h	28 Sep 2016 12:01:10 -0000
@@ -57,6 +57,7 @@
 #include <uvm/uvm_object.h>
 #include <uvm/uvm_page.h>
 #include <uvm/uvm_pager.h>
+#include <uvm/uvm_physmem.h>
 #include <uvm/uvm_pdaemon.h>
 #include <uvm/uvm_swap.h>
 
Index: sys/uvm/uvm_extern.h
===================================================================
RCS file: /cvsroot/src/sys/uvm/uvm_extern.h,v
retrieving revision 1.198
diff -u -r1.198 uvm_extern.h
--- sys/uvm/uvm_extern.h	20 Jul 2016 12:38:43 -0000	1.198
+++ sys/uvm/uvm_extern.h	28 Sep 2016 12:01:12 -0000
@@ -708,9 +708,6 @@
 			    struct vm_page *);
 void			uvm_pagerealloc(struct vm_page *,
 			    struct uvm_object *, voff_t);
-/* Actually, uvm_page_physload takes PF#s which need their own type */
-void			uvm_page_physload(paddr_t, paddr_t, paddr_t,
-			    paddr_t, int);
 void			uvm_setpagesize(void);
 
 /* uvm_pager.c */
Index: sys/uvm/uvm_page.c
===================================================================
RCS file: /cvsroot/src/sys/uvm/uvm_page.c,v
retrieving revision 1.187
diff -u -r1.187 uvm_page.c
--- sys/uvm/uvm_page.c	11 Apr 2015 19:24:13 -0000	1.187
+++ sys/uvm/uvm_page.c	28 Sep 2016 12:01:18 -0000
@@ -87,6 +87,24 @@
 #include <uvm/uvm_pdpolicy.h>
 
 /*
+ * vm_physseg: describes one segment of physical memory
+ */
+struct vm_physseg {
+	paddr_t	start;			/* PF# of first page in segment */
+	paddr_t	end;			/* (PF# of last page in segment) + 1 */
+	paddr_t	avail_start;		/* PF# of first free page in segment */
+	paddr_t	avail_end;		/* (PF# of last free page in segment) +1  */
+	struct	vm_page *pgs;		/* vm_page structures (from start) */
+	struct	vm_page *lastpg;	/* vm_page structure for end */
+	int	free_list;		/* which free list they belong on */
+	u_int	start_hint;		/* start looking for free pages here */
+					/* protected by uvm_fpageqlock */
+#ifdef __HAVE_PMAP_PHYSSEG
+	struct	pmap_physseg pmseg;	/* pmap specific (MD) data */
+#endif
+};
+
+/*
  * global vars... XXXCDC: move to uvm. structure.
  */
 
@@ -94,9 +112,6 @@
  * physical memory config is stored in vm_physmem.
  */
 
-struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];	/* XXXCDC: uvm.physmem */
-int vm_nphysseg = 0;				/* XXXCDC: uvm.nphysseg */
-#define	vm_nphysmem	vm_nphysseg
 
 /*
  * Some supported CPUs in a given architecture don't support all
@@ -116,7 +131,7 @@
 /*
  * physical memory size;
  */
-int physmem;
+psize_t physmem;
 
 /*
  * local variables
@@ -337,11 +352,8 @@
 	static struct uvm_cpu boot_cpu;
 	psize_t freepages, pagecount, bucketcount, n;
 	struct pgflbucket *bucketarray, *cpuarray;
-	struct vm_physseg *seg;
 	struct vm_page *pagearray;
 	int lcv;
-	u_int i;
-	paddr_t paddr;
 
 	KASSERT(ncpu <= 1);
 	CTASSERT(sizeof(pagearray->offset) >= sizeof(struct uvm_cpu *));
@@ -369,7 +381,7 @@
 	 * now is to allocate vm_page structures for this memory.
 	 */
 
-	if (vm_nphysmem == 0)
+	if (uvm_physmem_get_last() == -1)
 		panic("uvm_page_bootstrap: no memory pre-allocated");
 
 	/*
@@ -381,9 +393,11 @@
 	 */
 
 	freepages = 0;
-	for (lcv = 0 ; lcv < vm_nphysmem ; lcv++) {
-		seg = VM_PHYSMEM_PTR(lcv);
-		freepages += (seg->end - seg->start);
+
+	for (lcv = uvm_physmem_get_first();
+	     lcv <= uvm_physmem_get_last() ;
+	     lcv = uvm_physmem_get_next(lcv)) {
+		freepages += (uvm_physmem_get_end(lcv) - uvm_physmem_get_start(lcv));
 	}
 
 	/*
@@ -428,31 +442,19 @@
 	/*
 	 * init the vm_page structures and put them in the correct place.
 	 */
+	for (lcv = uvm_physmem_get_first();
+	     lcv <= uvm_physmem_get_last();
+	     lcv = uvm_physmem_get_next(lcv)) {
+
+		n = uvm_physmem_get_end(lcv) - uvm_physmem_get_start(lcv);
+		n = ((n + 1) << PAGE_SHIFT) /
+		    (PAGE_SIZE + sizeof(struct vm_page));
 
-	for (lcv = 0 ; lcv < vm_nphysmem ; lcv++) {
-		seg = VM_PHYSMEM_PTR(lcv);
-		n = seg->end - seg->start;
+		uvm_physmem_init_seg(lcv, pagearray);
 
 		/* set up page array pointers */
-		seg->pgs = pagearray;
 		pagearray += n;
 		pagecount -= n;
-		seg->lastpg = seg->pgs + n;
-
-		/* init and free vm_pages (we've already zeroed them) */
-		paddr = ctob(seg->start);
-		for (i = 0 ; i < n ; i++, paddr += PAGE_SIZE) {
-			seg->pgs[i].phys_addr = paddr;
-#ifdef __HAVE_VM_PAGE_MD
-			VM_MDPAGE_INIT(&seg->pgs[i]);
-#endif
-			if (atop(paddr) >= seg->avail_start &&
-			    atop(paddr) < seg->avail_end) {
-				uvmexp.npages++;
-				/* add page to free pool */
-				uvm_pagefree(&seg->pgs[i]);
-			}
-		}
 	}
 
 	/*
@@ -625,92 +627,42 @@
 static bool
 uvm_page_physget_freelist(paddr_t *paddrp, int freelist)
 {
-	struct vm_physseg *seg;
-	int lcv, x;
+	int lcv;
 
 	/* pass 1: try allocating from a matching end */
 #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
-	for (lcv = vm_nphysmem - 1 ; lcv >= 0 ; lcv--)
+	for (lcv = uvm_physmem_get_last() ; lcv >= uvm_physmem_get_first() ; lcv = uvm_physmem_get_prev(lcv))
 #else
-	for (lcv = 0 ; lcv < vm_nphysmem ; lcv++)
+		for (lcv = uvm_physmem_get_first() ; lcv <= uvm_physmem_get_last() ; lcv = uvm_physmem_get_next(lcv))
 #endif
 	{
-		seg = VM_PHYSMEM_PTR(lcv);
-
 		if (uvm.page_init_done == true)
 			panic("uvm_page_physget: called _after_ bootstrap");
 
-		if (seg->free_list != freelist)
+		/* Try to match at front or back on unused segment */
+		if (uvm_page_physunload(lcv, freelist, paddrp) == false) {
+			if (paddrp == NULL) /* freelist fail, try next */
 			continue;
+		} else
+			return true;
 
-		/* try from front */
-		if (seg->avail_start == seg->start &&
-		    seg->avail_start < seg->avail_end) {
-			*paddrp = ctob(seg->avail_start);
-			seg->avail_start++;
-			seg->start++;
-			/* nothing left?   nuke it */
-			if (seg->avail_start == seg->end) {
-				if (vm_nphysmem == 1)
-				    panic("uvm_page_physget: out of memory!");
-				vm_nphysmem--;
-				for (x = lcv ; x < vm_nphysmem ; x++)
-					/* structure copy */
-					VM_PHYSMEM_PTR_SWAP(x, x + 1);
-			}
-			return (true);
-		}
-
-		/* try from rear */
-		if (seg->avail_end == seg->end &&
-		    seg->avail_start < seg->avail_end) {
-			*paddrp = ctob(seg->avail_end - 1);
-			seg->avail_end--;
-			seg->end--;
-			/* nothing left?   nuke it */
-			if (seg->avail_end == seg->start) {
-				if (vm_nphysmem == 1)
-				    panic("uvm_page_physget: out of memory!");
-				vm_nphysmem--;
-				for (x = lcv ; x < vm_nphysmem ; x++)
-					/* structure copy */
-					VM_PHYSMEM_PTR_SWAP(x, x + 1);
-			}
-			return (true);
-		}
-	}
 
 	/* pass2: forget about matching ends, just allocate something */
 #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
-	for (lcv = vm_nphysmem - 1 ; lcv >= 0 ; lcv--)
+	for (lcv = uvm_physmem_get_last() ; lcv >= uvm_physmem_get_first() ; lcv = uvm_physmem_get_prev(lcv))
 #else
-	for (lcv = 0 ; lcv < vm_nphysmem ; lcv++)
+		for (lcv = uvm_physmem_get_first() ; lcv <= uvm_physmem_get_last() ; lcv = uvm_physmem_get_next(lcv))
 #endif
 	{
-		seg = VM_PHYSMEM_PTR(lcv);
-
-		/* any room in this bank? */
-		if (seg->avail_start >= seg->avail_end)
-			continue;  /* nope */
-
-		*paddrp = ctob(seg->avail_start);
-		seg->avail_start++;
-		/* truncate! */
-		seg->start = seg->avail_start;
-
-		/* nothing left?   nuke it */
-		if (seg->avail_start == seg->end) {
-			if (vm_nphysmem == 1)
-				panic("uvm_page_physget: out of memory!");
-			vm_nphysmem--;
-			for (x = lcv ; x < vm_nphysmem ; x++)
-				/* structure copy */
-				VM_PHYSMEM_PTR_SWAP(x, x + 1);
+		/* Try the front regardless. */
+		if (uvm_page_physunload_force(lcv, freelist, paddrp) == false) {
+			if (paddrp == NULL) /* freelist fail, try next */
+				continue;
+		} else
+			return true;
 		}
-		return (true);
 	}
-
-	return (false);        /* whoops! */
+	return false;
 }
 
 bool
@@ -727,228 +679,6 @@
 #endif /* PMAP_STEAL_MEMORY */
 
 /*
- * uvm_page_physload: load physical memory into VM system
- *
- * => all args are PFs
- * => all pages in start/end get vm_page structures
- * => areas marked by avail_start/avail_end get added to the free page pool
- * => we are limited to VM_PHYSSEG_MAX physical memory segments
- */
-
-void
-uvm_page_physload(paddr_t start, paddr_t end, paddr_t avail_start,
-    paddr_t avail_end, int free_list)
-{
-	int preload, lcv;
-	psize_t npages;
-	struct vm_page *pgs;
-	struct vm_physseg *ps;
-
-	if (uvmexp.pagesize == 0)
-		panic("uvm_page_physload: page size not set!");
-	if (free_list >= VM_NFREELIST || free_list < VM_FREELIST_DEFAULT)
-		panic("uvm_page_physload: bad free list %d", free_list);
-	if (start >= end)
-		panic("uvm_page_physload: start >= end");
-
-	/*
-	 * do we have room?
-	 */
-
-	if (vm_nphysmem == VM_PHYSSEG_MAX) {
-		printf("uvm_page_physload: unable to load physical memory "
-		    "segment\n");
-		printf("\t%d segments allocated, ignoring 0x%llx -> 0x%llx\n",
-		    VM_PHYSSEG_MAX, (long long)start, (long long)end);
-		printf("\tincrease VM_PHYSSEG_MAX\n");
-		return;
-	}
-
-	/*
-	 * check to see if this is a "preload" (i.e. uvm_page_init hasn't been
-	 * called yet, so kmem is not available).
-	 */
-
-	for (lcv = 0 ; lcv < vm_nphysmem ; lcv++) {
-		if (VM_PHYSMEM_PTR(lcv)->pgs)
-			break;
-	}
-	preload = (lcv == vm_nphysmem);
-
-	/*
-	 * if VM is already running, attempt to kmem_alloc vm_page structures
-	 */
-
-	if (!preload) {
-		panic("uvm_page_physload: tried to add RAM after vm_mem_init");
-	} else {
-		pgs = NULL;
-		npages = 0;
-	}
-
-	/*
-	 * now insert us in the proper place in vm_physmem[]
-	 */
-
-#if (VM_PHYSSEG_STRAT == VM_PSTRAT_RANDOM)
-	/* random: put it at the end (easy!) */
-	ps = VM_PHYSMEM_PTR(vm_nphysmem);
-#elif (VM_PHYSSEG_STRAT == VM_PSTRAT_BSEARCH)
-	{
-		int x;
-		/* sort by address for binary search */
-		for (lcv = 0 ; lcv < vm_nphysmem ; lcv++)
-			if (start < VM_PHYSMEM_PTR(lcv)->start)
-				break;
-		ps = VM_PHYSMEM_PTR(lcv);
-		/* move back other entries, if necessary ... */
-		for (x = vm_nphysmem ; x > lcv ; x--)
-			/* structure copy */
-			VM_PHYSMEM_PTR_SWAP(x, x - 1);
-	}
-#elif (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
-	{
-		int x;
-		/* sort by largest segment first */
-		for (lcv = 0 ; lcv < vm_nphysmem ; lcv++)
-			if ((end - start) >
-			    (VM_PHYSMEM_PTR(lcv)->end - VM_PHYSMEM_PTR(lcv)->start))
-				break;
-		ps = VM_PHYSMEM_PTR(lcv);
-		/* move back other entries, if necessary ... */
-		for (x = vm_nphysmem ; x > lcv ; x--)
-			/* structure copy */
-			VM_PHYSMEM_PTR_SWAP(x, x - 1);
-	}
-#else
-	panic("uvm_page_physload: unknown physseg strategy selected!");
-#endif
-
-	ps->start = start;
-	ps->end = end;
-	ps->avail_start = avail_start;
-	ps->avail_end = avail_end;
-	if (preload) {
-		ps->pgs = NULL;
-	} else {
-		ps->pgs = pgs;
-		ps->lastpg = pgs + npages;
-	}
-	ps->free_list = free_list;
-	vm_nphysmem++;
-
-	if (!preload) {
-		uvmpdpol_reinit();
-	}
-}
-
-/*
- * when VM_PHYSSEG_MAX is 1, we can simplify these functions
- */
-
-#if VM_PHYSSEG_MAX == 1
-static inline int vm_physseg_find_contig(struct vm_physseg *, int, paddr_t, int *);
-#elif (VM_PHYSSEG_STRAT == VM_PSTRAT_BSEARCH)
-static inline int vm_physseg_find_bsearch(struct vm_physseg *, int, paddr_t, int *);
-#else
-static inline int vm_physseg_find_linear(struct vm_physseg *, int, paddr_t, int *);
-#endif
-
-/*
- * vm_physseg_find: find vm_physseg structure that belongs to a PA
- */
-int
-vm_physseg_find(paddr_t pframe, int *offp)
-{
-
-#if VM_PHYSSEG_MAX == 1
-	return vm_physseg_find_contig(vm_physmem, vm_nphysseg, pframe, offp);
-#elif (VM_PHYSSEG_STRAT == VM_PSTRAT_BSEARCH)
-	return vm_physseg_find_bsearch(vm_physmem, vm_nphysseg, pframe, offp);
-#else
-	return vm_physseg_find_linear(vm_physmem, vm_nphysseg, pframe, offp);
-#endif
-}
-
-#if VM_PHYSSEG_MAX == 1
-static inline int
-vm_physseg_find_contig(struct vm_physseg *segs, int nsegs, paddr_t pframe, int *offp)
-{
-
-	/* 'contig' case */
-	if (pframe >= segs[0].start && pframe < segs[0].end) {
-		if (offp)
-			*offp = pframe - segs[0].start;
-		return(0);
-	}
-	return(-1);
-}
-
-#elif (VM_PHYSSEG_STRAT == VM_PSTRAT_BSEARCH)
-
-static inline int
-vm_physseg_find_bsearch(struct vm_physseg *segs, int nsegs, paddr_t pframe, int *offp)
-{
-	/* binary search for it */
-	u_int	start, len, guess;
-
-	/*
-	 * if try is too large (thus target is less than try) we reduce
-	 * the length to trunc(len/2) [i.e. everything smaller than "try"]
-	 *
-	 * if the try is too small (thus target is greater than try) then
-	 * we set the new start to be (try + 1).   this means we need to
-	 * reduce the length to (round(len/2) - 1).
-	 *
-	 * note "adjust" below which takes advantage of the fact that
-	 *  (round(len/2) - 1) == trunc((len - 1) / 2)
-	 * for any value of len we may have
-	 */
-
-	for (start = 0, len = nsegs ; len != 0 ; len = len / 2) {
-		guess = start + (len / 2);	/* try in the middle */
-
-		/* start past our try? */
-		if (pframe >= segs[guess].start) {
-			/* was try correct? */
-			if (pframe < segs[guess].end) {
-				if (offp)
-					*offp = pframe - segs[guess].start;
-				return guess;            /* got it */
-			}
-			start = guess + 1;	/* next time, start here */
-			len--;			/* "adjust" */
-		} else {
-			/*
-			 * pframe before try, just reduce length of
-			 * region, done in "for" loop
-			 */
-		}
-	}
-	return(-1);
-}
-
-#else
-
-static inline int
-vm_physseg_find_linear(struct vm_physseg *segs, int nsegs, paddr_t pframe, int *offp)
-{
-	/* linear search for it */
-	int	lcv;
-
-	for (lcv = 0; lcv < nsegs; lcv++) {
-		if (pframe >= segs[lcv].start &&
-		    pframe < segs[lcv].end) {
-			if (offp)
-				*offp = pframe - segs[lcv].start;
-			return(lcv);		   /* got it */
-		}
-	}
-	return(-1);
-}
-#endif
-
-/*
  * PHYS_TO_VM_PAGE: find vm_page for a PA.   used by MI code to get vm_pages
  * back from an I/O mapping (ugh!).   used in some MD code as well.
  */
@@ -956,12 +686,12 @@
 uvm_phys_to_vm_page(paddr_t pa)
 {
 	paddr_t pf = atop(pa);
-	int	off;
+	paddr_t	off;
 	int	psi;
 
 	psi = vm_physseg_find(pf, &off);
 	if (psi != -1)
-		return(&VM_PHYSMEM_PTR(psi)->pgs[off]);
+		return uvm_physmem_get_pg(psi, off);
 	return(NULL);
 }
 
@@ -2019,7 +1749,7 @@
 
 	lcv = vm_physseg_find(atop(VM_PAGE_TO_PHYS(pg)), NULL);
 	KASSERT(lcv != -1);
-	return (VM_PHYSMEM_PTR(lcv)->free_list);
+	return uvm_physmem_get_free_list(lcv);
 }
 
 /*
@@ -2136,6 +1866,7 @@
 uvm_page_printall(void (*pr)(const char *, ...))
 {
 	unsigned i;
+	paddr_t pfn;
 	struct vm_page *pg;
 
 	(*pr)("%18s %4s %4s %18s %18s"
@@ -2143,8 +1874,14 @@
 	    " OWNER"
 #endif
 	    "\n", "PAGE", "FLAG", "PQ", "UOBJECT", "UANON");
-	for (i = 0; i < vm_nphysmem; i++) {
-		for (pg = VM_PHYSMEM_PTR(i)->pgs; pg < VM_PHYSMEM_PTR(i)->lastpg; pg++) {
+	for (i = uvm_physmem_get_first();
+	     uvm_physmem_valid(i);
+	     i = uvm_physmem_get_next(i)) {
+		for (pfn = uvm_physmem_get_start(i);
+		     pfn <= uvm_physmem_get_end(i);
+		     pfn++) {
+			pg = PHYS_TO_VM_PAGE(ptoa(pfn));
+
 			(*pr)("%18p %04x %04x %18p %18p",
 			    pg, pg->flags, pg->pqflags, pg->uobject,
 			    pg->uanon);
Index: sys/uvm/uvm_page.h
===================================================================
RCS file: /cvsroot/src/sys/uvm/uvm_page.h,v
retrieving revision 1.80
diff -u -r1.80 uvm_page.h
--- sys/uvm/uvm_page.h	23 Mar 2015 07:59:12 -0000	1.80
+++ sys/uvm/uvm_page.h	28 Sep 2016 12:01:19 -0000
@@ -294,24 +294,6 @@
 #define VM_PSTRAT_BSEARCH	2
 #define VM_PSTRAT_BIGFIRST	3
 
-/*
- * vm_physseg: describes one segment of physical memory
- */
-struct vm_physseg {
-	paddr_t	start;			/* PF# of first page in segment */
-	paddr_t	end;			/* (PF# of last page in segment) + 1 */
-	paddr_t	avail_start;		/* PF# of first free page in segment */
-	paddr_t	avail_end;		/* (PF# of last free page in segment) +1  */
-	struct	vm_page *pgs;		/* vm_page structures (from start) */
-	struct	vm_page *lastpg;	/* vm_page structure for end */
-	int	free_list;		/* which free list they belong on */
-	u_int	start_hint;		/* start looking for free pages here */
-					/* protected by uvm_fpageqlock */
-#ifdef __HAVE_PMAP_PHYSSEG
-	struct	pmap_physseg pmseg;	/* pmap specific (MD) data */
-#endif
-};
-
 #ifdef _KERNEL
 
 /*
@@ -321,21 +303,6 @@
 extern bool vm_page_zero_enable;
 
 /*
- * physical memory config is stored in vm_physmem.
- */
-
-#define	VM_PHYSMEM_PTR(i)	(&vm_physmem[i])
-#if VM_PHYSSEG_MAX == 1
-#define VM_PHYSMEM_PTR_SWAP(i, j) /* impossible */
-#else
-#define VM_PHYSMEM_PTR_SWAP(i, j) \
-	do { vm_physmem[(i)] = vm_physmem[(j)]; } while (0)
-#endif
-
-extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
-extern int vm_nphysseg;
-
-/*
  * prototypes: the following prototypes define the interface to pages
  */
 
@@ -366,10 +333,14 @@
 
 int uvm_page_lookup_freelist(struct vm_page *);
 
-int vm_physseg_find(paddr_t, int *);
+int vm_physseg_find(paddr_t, psize_t *);
 struct vm_page *uvm_phys_to_vm_page(paddr_t);
 paddr_t uvm_vm_page_to_phys(const struct vm_page *);
 
+#if !defined(PMAP_STEAL_MEMORY)
+bool uvm_page_physget(paddr_t *);
+#endif
+
 /*
  * macros
  */
Index: sys/uvm/uvm_pglist.c
===================================================================
RCS file: /cvsroot/src/sys/uvm/uvm_pglist.c,v
retrieving revision 1.67
diff -u -r1.67 uvm_pglist.c
--- sys/uvm/uvm_pglist.c	26 Oct 2014 01:42:07 -0000	1.67
+++ sys/uvm/uvm_pglist.c	28 Sep 2016 12:01:20 -0000
@@ -116,11 +116,10 @@
 }
 
 static int
-uvm_pglistalloc_c_ps(struct vm_physseg *ps, int num, paddr_t low, paddr_t high,
+uvm_pglistalloc_c_ps(int psi, int num, paddr_t low, paddr_t high,
     paddr_t alignment, paddr_t boundary, struct pglist *rlist)
 {
 	signed int candidate, limit, candidateidx, end, idx, skip;
-	struct vm_page *pgs;
 	int pagemask;
 	bool second_pass;
 #ifdef DEBUG
@@ -140,26 +139,26 @@
 	/*
 	 * Make sure that physseg falls within with range to be allocated from.
 	 */
-	if (high <= ps->avail_start || low >= ps->avail_end)
+	if (high <= uvm_physmem_get_avail_start(psi) || low >= uvm_physmem_get_avail_end(psi))
 		return 0;
 
 	/*
 	 * We start our search at the just after where the last allocation
 	 * succeeded.
 	 */
-	candidate = roundup2(max(low, ps->avail_start + ps->start_hint), alignment);
-	limit = min(high, ps->avail_end);
+	candidate = roundup2(max(low, uvm_physmem_get_avail_start(psi) +
+		uvm_physmem_get_start_hint(psi)), alignment);
+	limit = min(high, uvm_physmem_get_avail_end(psi));
 	pagemask = ~((boundary >> PAGE_SHIFT) - 1);
 	skip = 0;
 	second_pass = false;
-	pgs = ps->pgs;
 
 	for (;;) {
 		bool ok = true;
 		signed int cnt;
 
 		if (candidate + num > limit) {
-			if (ps->start_hint == 0 || second_pass) {
+			if (uvm_physmem_get_start_hint(psi) == 0 || second_pass) {
 				/*
 				 * We've run past the allowable range.
 				 */
@@ -171,8 +170,9 @@
 			 * is were we started.
 			 */
 			second_pass = true;
-			candidate = roundup2(max(low, ps->avail_start), alignment);
-			limit = min(limit, ps->avail_start + ps->start_hint);
+			candidate = roundup2(max(low, uvm_physmem_get_avail_start(psi)), alignment);
+			limit = min(limit, uvm_physmem_get_avail_start(psi) +
+			    uvm_physmem_get_start_hint(psi));
 			skip = 0;
 			continue;
 		}
@@ -201,7 +201,7 @@
 		if (cidx != candidate - ps->start + num - 1)
 			panic("pgalloc contig: botch4");
 #endif
-		candidateidx = candidate - ps->start;
+		candidateidx = candidate - uvm_physmem_get_start(psi);
 		end = candidateidx + num;
 
 		/*
@@ -220,7 +220,7 @@
 		 * testing most of those pages again in the next pass.
 		 */
 		for (idx = end - 1; idx >= candidateidx + skip; idx--) {
-			if (VM_PAGE_IS_FREE(&pgs[idx]) == 0) {
+			if (VM_PAGE_IS_FREE(uvm_physmem_get_pg(psi, idx)) == 0) {
 				ok = false;
 				break;
 			}
@@ -228,7 +228,7 @@
 #ifdef DEBUG
 			if (idx > candidateidx) {
 				idxpa = VM_PAGE_TO_PHYS(&pgs[idx]);
-				lastidxpa = VM_PAGE_TO_PHYS(&pgs[idx - 1]);
+				lastidxpa = VM_PAGE_TO_PHYS(uvm_physmem_get_pg(psi, idx));
 				if ((lastidxpa + PAGE_SIZE) != idxpa) {
 					/*
 					 * Region not contiguous.
@@ -249,7 +249,7 @@
 
 		if (ok) {
 			while (skip-- > 0) {
-				KDASSERT(VM_PAGE_IS_FREE(&pgs[candidateidx + skip]));
+				KDASSERT(VM_PAGE_IS_FREE(uvm_physmem_get_pg(psi, candidateidx + skip)));
 			}
 #ifdef PGALLOC_VERBOSE
 			printf(": ok\n");
@@ -280,19 +280,22 @@
 	/*
 	 * we have a chunk of memory that conforms to the requested constraints.
 	 */
-	for (idx = candidateidx, pgs += idx; idx < end; idx++, pgs++)
-		uvm_pglist_add(pgs, rlist);
+	for (idx = candidateidx; idx < end; idx++)
+		uvm_pglist_add(uvm_physmem_get_pg(psi, idx), rlist);
 
 	/*
 	 * the next time we need to search this segment, start after this
 	 * chunk of pages we just allocated.
 	 */
-	ps->start_hint = candidate + num - ps->avail_start;
-	KASSERTMSG(ps->start_hint <= ps->avail_end - ps->avail_start,
+	uvm_physmem_set_start_hint(psi, candidate + num -
+	    uvm_physmem_get_avail_start(psi));
+	KASSERTMSG(uvm_physmem_get_start_hint(psi) <=
+	    uvm_physmem_get_avail_end(psi) - uvm_physmem_get_avail_start(psi),
 	    "%x %u (%#x) <= %#"PRIxPADDR" - %#"PRIxPADDR" (%#"PRIxPADDR")",
 	    candidate + num,
-	    ps->start_hint, ps->start_hint, ps->avail_end, ps->avail_start,
-	    ps->avail_end - ps->avail_start);
+	    uvm_physmem_get_start_hint(psi), uvm_physmem_get_start_hint(psi),
+	    uvm_physmem_get_avail_end(psi), uvm_physmem_get_avail_start(psi),
+	    uvm_physmem_get_avail_end(psi) - uvm_physmem_get_avail_start(psi));
 
 #ifdef PGALLOC_VERBOSE
 	printf("got %d pgs\n", num);
@@ -305,7 +308,6 @@
     paddr_t boundary, struct pglist *rlist)
 {
 	int fl, psi;
-	struct vm_physseg *ps;
 	int error;
 
 	/* Default to "lose". */
@@ -322,17 +324,16 @@
 
 	for (fl = 0; fl < VM_NFREELIST; fl++) {
 #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
-		for (psi = vm_nphysseg - 1 ; psi >= 0 ; psi--)
+		for (psi = uvm_physmem_get_last(); uvm_physmem_valid(psi); psi = uvm_physmem_get_prev(psi))
+			 
 #else
-		for (psi = 0 ; psi < vm_nphysseg ; psi++)
+		for (psi = uvm_physmem_get_first(); uvm_physmem_valid(psi); psi = uvm_physmem_get_next(psi))
 #endif
 		{
-			ps = &vm_physmem[psi];
-
-			if (ps->free_list != fl)
+			if (uvm_physmem_get_free_list(psi) != fl)
 				continue;
 
-			num -= uvm_pglistalloc_c_ps(ps, num, low, high,
+			num -= uvm_pglistalloc_c_ps(psi, num, low, high,
 						    alignment, boundary, rlist);
 			if (num == 0) {
 #ifdef PGALLOC_VERBOSE
@@ -358,7 +359,7 @@
 }
 
 static int
-uvm_pglistalloc_s_ps(struct vm_physseg *ps, int num, paddr_t low, paddr_t high,
+uvm_pglistalloc_s_ps(int psi, int num, paddr_t low, paddr_t high,
     struct pglist *rlist)
 {
 	int todo, limit, candidate;
@@ -369,36 +370,39 @@
 #endif
 
 	KASSERT(mutex_owned(&uvm_fpageqlock));
-	KASSERT(ps->start <= ps->avail_start);
-	KASSERT(ps->start <= ps->avail_end);
-	KASSERT(ps->avail_start <= ps->end);
-	KASSERT(ps->avail_end <= ps->end);
+	KASSERT(uvm_physmem_get_start(psi) <= uvm_physmem_get_avail_start(psi));
+	KASSERT(uvm_physmem_get_start(psi) <= uvm_physmem_get_avail_end(psi));
+	KASSERT(uvm_physmem_get_avail_start(psi) <= uvm_physmem_get_end(psi));
+	KASSERT(uvm_physmem_get_avail_end(psi) <= uvm_physmem_get_end(psi));
 
 	low = atop(low);
 	high = atop(high);
 	todo = num;
-	candidate = max(low, ps->avail_start + ps->start_hint);
-	limit = min(high, ps->avail_end);
-	pg = &ps->pgs[candidate - ps->start];
+	candidate = max(low, uvm_physmem_get_avail_start(psi) +
+	    uvm_physmem_get_start_hint(psi));
+	limit = min(high, uvm_physmem_get_avail_end(psi));
+	pg = uvm_physmem_get_pg(psi, candidate - uvm_physmem_get_start(psi));
 	second_pass = false;
 
 	/*
 	 * Make sure that physseg falls within with range to be allocated from.
 	 */
-	if (high <= ps->avail_start || low >= ps->avail_end)
+	if (high <= uvm_physmem_get_avail_start(psi) ||
+	    low >= uvm_physmem_get_avail_end(psi))
 		return 0;
 
 again:
 	for (;; candidate++, pg++) {
 		if (candidate >= limit) {
-			if (ps->start_hint == 0 || second_pass) {
+			if (uvm_physmem_get_start_hint(psi) == 0 || second_pass) {
 				candidate = limit - 1;
 				break;
 			}
 			second_pass = true;
-			candidate = max(low, ps->avail_start);
-			limit = min(limit, ps->avail_start + ps->start_hint);
-			pg = &ps->pgs[candidate - ps->start];
+			candidate = max(low, uvm_physmem_get_avail_start(psi));
+			limit = min(limit, uvm_physmem_get_avail_start(psi) +
+			    uvm_physmem_get_start_hint(psi));
+			pg = uvm_physmem_get_pg(psi, candidate - uvm_physmem_get_start(psi));
 			goto again;
 		}
 #if defined(DEBUG)
@@ -426,12 +430,16 @@
 	 * The next time we need to search this segment,
 	 * start just after the pages we just allocated.
 	 */
-	ps->start_hint = candidate + 1 - ps->avail_start;
-	KASSERTMSG(ps->start_hint <= ps->avail_end - ps->avail_start,
+	uvm_physmem_set_start_hint(psi, candidate + 1 - uvm_physmem_get_avail_start(psi));
+	KASSERTMSG(uvm_physmem_get_start_hint(psi) <= uvm_physmem_get_avail_end(psi) -
+	    uvm_physmem_get_avail_start(psi),
 	    "%#x %u (%#x) <= %#"PRIxPADDR" - %#"PRIxPADDR" (%#"PRIxPADDR")",
 	    candidate + 1,
-	    ps->start_hint, ps->start_hint, ps->avail_end, ps->avail_start,
-	    ps->avail_end - ps->avail_start);
+	    uvm_physmem_get_start_hint(psi),
+	    uvm_physmem_get_start_hint(psi),
+	    uvm_physmem_get_avail_end(psi),
+	    uvm_physmem_get_avail_start(psi),
+	    uvm_physmem_get_avail_end(psi) - uvm_physmem_get_avail_start(psi));
 
 #ifdef PGALLOC_VERBOSE
 	printf("got %d pgs\n", num - todo);
@@ -444,7 +452,6 @@
     struct pglist *rlist, int waitok)
 {
 	int fl, psi, error;
-	struct vm_physseg *ps;
 
 	/* Default to "lose". */
 	error = ENOMEM;
@@ -461,17 +468,16 @@
 
 	for (fl = 0; fl < VM_NFREELIST; fl++) {
 #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
-		for (psi = vm_nphysseg - 1 ; psi >= 0 ; psi--)
+		for (psi = uvm_physmem_get_last(); uvm_physmem_valid(psi); psi = uvm_physmem_get_prev(psi))
+			 
 #else
-		for (psi = 0 ; psi < vm_nphysseg ; psi++)
+		for (psi = uvm_physmem_get_first(); uvm_physmem_valid(psi); psi = uvm_physmem_get_next(psi))
 #endif
 		{
-			ps = &vm_physmem[psi];
-
-			if (ps->free_list != fl)
+			if (uvm_physmem_get_free_list(psi) != fl)
 				continue;
 
-			num -= uvm_pglistalloc_s_ps(ps, num, low, high, rlist);
+			num -= uvm_pglistalloc_s_ps(psi, num, low, high, rlist);
 			if (num == 0) {
 				error = 0;
 				goto out;