Cleanup the chunk placement routine by removing the conflict resolver.

Chunks are now sorted by ascending PA and all chunks are bounced before
unpack. This fixes an issue where the trampoline chunks were being placed
at the end of the unpack ordering, causing overwrite during unpack.

1 files changed, 47 insertions, 106 deletions

diff --git a/sys/kern/subr_hibernate.c b/sys/kern/subr_hibernate.c
index c5f8879d50b..6dc6e5c7284 100644
--- a/sys/kern/subr_hibernate.c
+++ b/sys/kern/subr_hibernate.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: subr_hibernate.c,v 1.93 2014/07/09 12:43:51 mlarkin Exp $	*/
+/*	$OpenBSD: subr_hibernate.c,v 1.94 2014/07/09 14:10:25 mlarkin Exp $	*/
 
 /*
  * Copyright (c) 2011 Ariane van der Steldt <ariane@stack.nl>
@@ -100,6 +100,32 @@ struct hiballoc_entry {
 };
 
 /*
+ * Sort hibernate memory ranges by ascending PA
+ */
+void
+hibernate_sort_ranges(union hibernate_info *hib_info)
+{
+	int i, j;
+	struct hibernate_memory_range *ranges;
+	paddr_t base, end;
+
+	ranges = hib_info->ranges;
+
+	for (i = 1; i < hib_info->nranges; i++) {
+		j = i;
+		while (j > 0 && ranges[j - 1].base > ranges[j].base) {
+			base = ranges[j].base;
+			end = ranges[j].end;
+			ranges[j].base = ranges[j - 1].base;
+			ranges[j].end = ranges[j - 1].end;
+			ranges[j - 1].base = base;
+			ranges[j - 1].end = end;
+			j--;
+		}
+	}
+}
+
+/*
  * Compare hiballoc entries based on the address they manage.
  *
  * Since the address is fixed, relative to struct hiballoc_entry,
@@ -1663,17 +1689,17 @@ hibernate_read_chunks(union hibernate_info *hib, paddr_t pig_start,
     paddr_t pig_end, size_t image_compr_size,
     struct hibernate_disk_chunk *chunks)
 {
-	paddr_t img_index, img_cur, r1s, r1e, r2s, r2e;
-	paddr_t copy_start, copy_end;
-	paddr_t piglet_base = hib->piglet_pa;
-	paddr_t piglet_end = piglet_base + HIBERNATE_CHUNK_SIZE;
+	paddr_t img_cur, piglet_base;
 	daddr_t blkctr;
 	size_t processed, compressed_size, read_size;
-	int overlap, found, nchunks, nochunks = 0, nfchunks = 0, npchunks = 0;
-	int num_io_pages;
-	short *ochunks, *pchunks, *fchunks, i, j;
-	vaddr_t tempva = (vaddr_t)NULL, hibernate_fchunk_area = (vaddr_t)NULL;
-
+	int nchunks, nfchunks, num_io_pages;
+	vaddr_t tempva, hibernate_fchunk_area;
+	short *fchunks, i, j;
+
+	tempva = (vaddr_t)NULL;
+	hibernate_fchunk_area = (vaddr_t)NULL;
+	nfchunks = 0;
+	piglet_base = hib->piglet_pa;
 	global_pig_start = pig_start;
 
 	pmap_activate(curproc);
@@ -1687,7 +1713,7 @@ hibernate_read_chunks(union hibernate_info *hib, paddr_t pig_start,
 		&kd_nowait);
 	if (!tempva)
 		return (1);
-	hibernate_fchunk_area = (vaddr_t)km_alloc(24*PAGE_SIZE, &kv_any,
+	hibernate_fchunk_area = (vaddr_t)km_alloc(24 * PAGE_SIZE, &kv_any,
 	    &kp_none, &kd_nowait);
 	if (!hibernate_fchunk_area)
 		return (1);
@@ -1695,16 +1721,10 @@ hibernate_read_chunks(union hibernate_info *hib, paddr_t pig_start,
 	/* Final output chunk ordering VA */
 	fchunks = (short *)hibernate_fchunk_area;
 
-	/* Piglet chunk ordering VA */
-	pchunks = (short *)(hibernate_fchunk_area + (8*PAGE_SIZE));
-
-	/* Final chunk ordering VA */
-	ochunks = (short *)(hibernate_fchunk_area + (16*PAGE_SIZE));
-
 	/* Map the chunk ordering region */
-	for(i=0; i<24 ; i++)
-		pmap_kenter_pa(hibernate_fchunk_area + (i*PAGE_SIZE),
-			piglet_base + ((4+i)*PAGE_SIZE), VM_PROT_ALL);
+	for(i = 0; i < 24 ; i++)
+		pmap_kenter_pa(hibernate_fchunk_area + (i * PAGE_SIZE),
+			piglet_base + ((4 + i) * PAGE_SIZE), VM_PROT_ALL);
 	pmap_update(pmap_kernel());
 
 	nchunks = hib->chunk_ctr;
@@ -1719,97 +1739,20 @@ hibernate_read_chunks(union hibernate_info *hib, paddr_t pig_start,
 	 */
 	for (i = 0; i < nchunks; i++) {
 		if (chunks[i].end <= pig_start || chunks[i].base >= pig_end) {
-			ochunks[nochunks] = i;
 			fchunks[nfchunks] = i;
-			nochunks++;
 			nfchunks++;
-			chunks[i].flags |= HIBERNATE_CHUNK_USED;
+			chunks[i].flags |= HIBERNATE_CHUNK_PLACED;
 		}
 	}
 
 	/*
 	 * Walk the ordering, place the chunks in ascending memory order.
-	 * Conflicts might arise, these are handled next.
 	 */
-	do {
-		img_index = -1;
-		found = 0;
-		j = -1;
-		for (i = 0; i < nchunks; i++)
-			if (chunks[i].base < img_index &&
-			    chunks[i].flags == 0 ) {
-				j = i;
-				img_index = chunks[i].base;
-			}
-
-		if (j != -1) {
-			found = 1;
-			ochunks[nochunks] = j;
-			nochunks++;
-			chunks[j].flags |= HIBERNATE_CHUNK_PLACED;
-		}
-	} while (found);
-
-	img_index = pig_start;
-
-	/*
-	 * Identify chunk output conflicts (chunks whose pig load area
-	 * corresponds to their original memory placement location)
-	 */
-	for (i = 0; i < nochunks ; i++) {
-		overlap = 0;
-		r1s = img_index;
-		r1e = img_index + chunks[ochunks[i]].compressed_size;
-		r2s = chunks[ochunks[i]].base;
-		r2e = chunks[ochunks[i]].end;
-
-		overlap = hibernate_check_overlap(r1s, r1e, r2s, r2e);
-		if (overlap)
-			chunks[ochunks[i]].flags |= HIBERNATE_CHUNK_CONFLICT;
-		img_index += chunks[ochunks[i]].compressed_size;
-	}
-
-	/*
-	 * Prepare the final output chunk list. Calculate an output
-	 * inflate strategy for overlapping chunks if needed.
-	 */
-	for (i = 0; i < nochunks ; i++) {
-		/*
-		 * If a conflict is detected, consume enough compressed
-		 * output chunks to fill the piglet
-		 */
-		if (chunks[ochunks[i]].flags & HIBERNATE_CHUNK_CONFLICT) {
-			copy_start = piglet_base;
-			copy_end = piglet_end;
-			npchunks = 0;
-			j = i;
-
-			while (copy_start < copy_end && j < nochunks) {
-				pchunks[npchunks] = ochunks[j];
-				npchunks++;
-				copy_start +=
-				    chunks[ochunks[j]].compressed_size;
-				i++;
-				j++;
-			}
-
-			for (j = 0; j < npchunks; j++) {
-				fchunks[nfchunks] = pchunks[j];
-				chunks[pchunks[j]].flags |=
-				    HIBERNATE_CHUNK_USED;
-				nfchunks++;
-			}
-		} else {
-			/*
-			 * No conflict, chunk can be added without copying
-			 */
-			if ((chunks[ochunks[i]].flags &
-			    HIBERNATE_CHUNK_USED) == 0) {
-				fchunks[nfchunks] = ochunks[i];
-				chunks[ochunks[i]].flags |=
-				    HIBERNATE_CHUNK_USED;
-				nfchunks++;
-			}
+	for (i = 0; i < nchunks; i++) {
+		if (chunks[i].flags != HIBERNATE_CHUNK_PLACED) {
+			fchunks[nfchunks] = i;
+			nfchunks++;
+			chunks[i].flags = HIBERNATE_CHUNK_PLACED;
 		}
 	}
 
@@ -1858,9 +1801,7 @@ hibernate_read_chunks(union hibernate_info *hib, paddr_t pig_start,
 		}
 	}
 
-	pmap_kremove(hibernate_fchunk_area, PAGE_SIZE);
-	pmap_kremove((vaddr_t)pchunks, PAGE_SIZE);
-	pmap_kremove((vaddr_t)fchunks, PAGE_SIZE);
+	pmap_kremove(hibernate_fchunk_area, 24 * PAGE_SIZE);
 	pmap_update(pmap_kernel());	
 
 	return (0);