new function uvm_hibswap() finds a the largest free zone in swap, which

hibernate can use place the data.
ok mlarkin

3 files changed, 50 insertions, 43 deletions

diff --git a/sys/kern/subr_hibernate.c b/sys/kern/subr_hibernate.c
index bab98e515f5..703934159b4 100644
--- a/sys/kern/subr_hibernate.c
+++ b/sys/kern/subr_hibernate.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: subr_hibernate.c,v 1.67 2013/11/05 00:51:58 krw Exp $	*/
+/*	$OpenBSD: subr_hibernate.c,v 1.68 2013/11/05 06:02:44 deraadt Exp $	*/
 
 /*
  * Copyright (c) 2011 Ariane van der Steldt <ariane@stack.nl>
@@ -728,12 +728,6 @@ get_hibernate_info(union hibernate_info *hiber_info, int suspend)
 	if (get_hibernate_info_md(hiber_info))
 		goto fail;
 
-	/* Calculate memory image location in swap */
-	hiber_info->image_offset = DL_GETPOFFSET(&dl.d_partitions[1]) +
-	    DL_GETPSIZE(&dl.d_partitions[1]) -
-	    (hiber_info->image_size / hiber_info->secsize) -
-	    sizeof(union hibernate_info)/hiber_info->secsize -
-	    chunktable_size;
 
 	return (0);
 fail:
@@ -1208,8 +1202,6 @@ hibernate_resume(void)
 	hibernate_quiesce_cpus();
 #endif /* MULTIPROCESSOR */
 
-	printf("Unhibernating...");
-
 	/* Read the image from disk into the image (pig) area */
 	if (hibernate_read_image(&disk_hiber_info))
 		goto fail;
@@ -1671,7 +1663,9 @@ hibernate_read_image(union hibernate_info *hiber_info)
 
 	disk_size = compressed_size;
 
-	printf(" (image size: %zu)\n", compressed_size);
+	printf("unhibernating @ block %lld length %lu blocks\n",
+	    hiber_info->sig_offset - chunktable_size,
+	    compressed_size);
 
 	/* Allocate the pig area */
 	pig_sz = compressed_size + HIBERNATE_CHUNK_SIZE;
@@ -1927,7 +1921,7 @@ int
 hibernate_suspend(void)
 {
 	union hibernate_info hib_info;
-	size_t swap_size;
+	u_long start, end;
 
 	/*
 	 * Calculate memory ranges, swap offsets, etc.
@@ -1939,14 +1933,26 @@ hibernate_suspend(void)
 		return (1);
 	}
 
-	swap_size = hib_info.image_size + hib_info.secsize +
-		HIBERNATE_CHUNK_TABLE_SIZE;
+	/* Find a page-addressed region in swap [start,end] */
+	if (uvm_hibswap(hib_info.device, &start, &end)) {
+		printf("cannot find any swap\n");
+		return (1);
+	}
 
-	if (uvm_swap_check_range(hib_info.device, swap_size)) {
-		printf("insufficient swap space for hibernate\n");
+	if (end - start < 1000) {
+		printf("%lu\n is too small", end - start);
 		return (1);
 	}
 
+	/* Calculate block offsets in swap */
+	hib_info.image_offset = ctod(start) + hib_info.swap_offset;
+
+#if 0
+	/* XXX side effect */
+	printf("hibernate @ block %lld max-length %lu blocks\n",
+	    hib_info.image_offset, ctod(end) - ctod(start));
+#endif
+
 	pmap_kenter_pa(HIBERNATE_HIBALLOC_PAGE, HIBERNATE_HIBALLOC_PAGE,
 		VM_PROT_ALL);
 	pmap_activate(curproc);
diff --git a/sys/uvm/uvm_swap.c b/sys/uvm/uvm_swap.c
index 75362c5aaca..348a0a3623f 100644
--- a/sys/uvm/uvm_swap.c
+++ b/sys/uvm/uvm_swap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_swap.c,v 1.119 2013/11/04 19:42:47 deraadt Exp $	*/
+/*	$OpenBSD: uvm_swap.c,v 1.120 2013/11/05 06:02:45 deraadt Exp $	*/
 /*	$NetBSD: uvm_swap.c,v 1.40 2000/11/17 11:39:39 mrg Exp $	*/
 
 /*
@@ -2024,21 +2024,16 @@ gotit:
 }
 
 #ifdef HIBERNATE
-/*
- * Check if free swap available at end of swap dev swdev.
- * Used by hibernate to check for usable swap area before writing the image
- */
 int
-uvm_swap_check_range(dev_t swdev, size_t size)
+uvm_hibswap(dev_t dev, u_long *sp, u_long *ep)
 {
 	struct swapdev *sdp, *swd = NULL;
 	struct swappri *spp;
-	struct extent *ex;
-	struct extent_region *exr;
-	int r = 0, start,  npages = size / PAGE_SIZE;
+	struct extent_region *exr, *exrn;
+	u_long start = 0, end = 0, size = 0;
 
 	/* no swap devices configured yet? */
-	if (uvmexp.nswapdev < 1)
+	if (uvmexp.nswapdev < 1 || dev != swdevt[0].sw_dev)
 		return (1);
 
 	for (spp = LIST_FIRST(&swap_priority); spp != NULL;
@@ -2046,28 +2041,34 @@ uvm_swap_check_range(dev_t swdev, size_t size)
 		for (sdp = CIRCLEQ_FIRST(&spp->spi_swapdev);
 		     sdp != (void *)&spp->spi_swapdev;
 		     sdp = CIRCLEQ_NEXT(sdp,swd_next)) {
-			if (sdp->swd_dev == swdev)
+			if (sdp->swd_dev == dev)
 				swd = sdp;
 		}
 
-	if (swd == NULL)
-		return (1);
-
-	if ((swd->swd_flags & SWF_ENABLE) == 0)
+	if (swd == NULL || (swd->swd_flags & SWF_ENABLE) == 0)
 		return (1);
 
-	ex = swd->swd_ex;
-	start = swd->swd_drumsize-npages;
-
-	if (npages > swd->swd_drumsize)
-		return (1); 
-
-	LIST_FOREACH(exr, &ex->ex_regions, er_link)
-		{
-			if (exr->er_end >= start)
-				r = 1;
+	LIST_FOREACH(exr, &swd->swd_ex->ex_regions, er_link) {
+		u_long gapstart, gapend, gapsize;
+	
+		gapstart = exr->er_end + 1;
+		exrn = LIST_NEXT(exr, er_link);
+		if (!exrn)
+			break;
+		gapend = exrn->er_start - 1;
+		gapsize = gapend - gapstart;
+		if (gapsize > size) {
+			start = gapstart;
+			end = gapend;
+			size = gapsize;
 		}
+	}
 
-	return (r);
+	if (size) {
+		*sp = start;
+		*ep = end;
+		return (0);
+	}
+	return (1);
 }
 #endif /* HIBERNATE */
diff --git a/sys/uvm/uvm_swap.h b/sys/uvm/uvm_swap.h
index 0dbcf23c60f..bd3ff0a1809 100644
--- a/sys/uvm/uvm_swap.h
+++ b/sys/uvm/uvm_swap.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_swap.h,v 1.15 2012/07/11 16:00:15 mlarkin Exp $	*/
+/*	$OpenBSD: uvm_swap.h,v 1.16 2013/11/05 06:02:45 deraadt Exp $	*/
 /*	$NetBSD: uvm_swap.h,v 1.5 2000/01/11 06:57:51 chs Exp $	*/
 
 /*
@@ -45,7 +45,7 @@ void			uvm_swap_free(int, int);
 void			uvm_swap_markbad(int, int);
 void			uvm_swap_freepages(struct vm_page **, int);
 #ifdef HIBERNATE
-int			uvm_swap_check_range(dev_t, size_t);
+int			uvm_hibswap(dev_t, u_long *, u_long *);
 #endif /* HIBERNATE */
 #ifdef UVM_SWAP_ENCRYPT
 void			uvm_swap_initcrypt_all(void);