minidump: Use the provided dump bitset

When constructing the set of dumpable pages, use the bitset provided by
the state argument, rather than assuming vm_page_dump invariably. For
normal kernel minidumps this will be a pointer to vm_page_dump, but when
dumping the live system it will not.

To do this, the functions in vm_dumpset.h are extended to accept the
desired bitset as an argument. Note that this provided bitset is assumed
to be derived from vm_page_dump, and therefore has the same size.

Reviewed by:	kib, markj, jhb
MFC after:	2 weeks
Sponsored by:	Juniper Networks, Inc.
Sponsored by:	Klara, Inc.
Differential Revision:	https://reviews.freebsd.org/D31992

(cherry picked from commit 10fe6f80a6c871ba317ddc2684cecb8f02096943)

12 files changed, 71 insertions, 57 deletions

diff --git a/sys/amd64/amd64/minidump_machdep.c b/sys/amd64/amd64/minidump_machdep.c
index 8d2bc3bca84a..de8433ae5a05 100644
--- a/sys/amd64/amd64/minidump_machdep.c
+++ b/sys/amd64/amd64/minidump_machdep.c
@@ -211,7 +211,8 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 			pa = pdpe & PG_PS_FRAME;
 			for (n = 0; n < NPDEPG * NPTEPG; n++) {
 				if (vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 				pa += PAGE_SIZE;
 			}
 			continue;
@@ -229,7 +230,8 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 				pa = pde & PG_PS_FRAME;
 				for (k = 0; k < NPTEPG; k++) {
 					if (vm_phys_is_dumpable(pa))
-						dump_add_page(pa);
+						vm_page_dump_add(
+						    state->dump_bitset, pa);
 					pa += PAGE_SIZE;
 				}
 				continue;
@@ -238,7 +240,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 			pa = pde & PG_FRAME;
 			/* set bit for this PTE page */
 			if (vm_phys_is_dumpable(pa))
-				dump_add_page(pa);
+				vm_page_dump_add(state->dump_bitset, pa);
 			/* and for each valid page in this 2MB block */
 			pt = (uint64_t *)PHYS_TO_DMAP(pde & PG_FRAME);
 			for (k = 0; k < NPTEPG; k++) {
@@ -247,7 +249,8 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 					continue;
 				pa = pte & PG_FRAME;
 				if (PHYS_IN_DMAP(pa) && vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 			}
 		}
 	}
@@ -258,12 +261,12 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		/* Clear out undumpable pages now if needed */
 		if (PHYS_IN_DMAP(pa) && vm_phys_is_dumpable(pa)) {
 			dumpsize += PAGE_SIZE;
 		} else {
-			dump_drop_page(pa);
+			vm_page_dump_drop(state->dump_bitset, pa);
 		}
 	}
 	dumpsize += PAGE_SIZE;
@@ -315,7 +318,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 		goto fail;
 
 	/* Dump bitmap */
-	error = blk_write(di, (char *)vm_page_dump, 0,
+	error = blk_write(di, (char *)state->dump_bitset, 0,
 	    round_page(BITSET_SIZE(vm_page_dump_pages)));
 	if (error)
 		goto fail;
@@ -373,7 +376,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	}
 
 	/* Dump memory chunks */
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		error = blk_write(di, 0, pa, PAGE_SIZE);
 		if (error)
 			goto fail;
diff --git a/sys/arm/arm/minidump_machdep.c b/sys/arm/arm/minidump_machdep.c
index 76ce89f895e3..ab3034237d17 100644
--- a/sys/arm/arm/minidump_machdep.c
+++ b/sys/arm/arm/minidump_machdep.c
@@ -186,7 +186,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	for (va = KERNBASE; va < kva_end; va += PAGE_SIZE) {
 		pa = pmap_dump_kextract(va, NULL);
 		if (pa != 0 && vm_phys_is_dumpable(pa))
-			dump_add_page(pa);
+			vm_page_dump_add(state->dump_bitset, pa);
 		ptesize += sizeof(pt2_entry_t);
 	}
 
@@ -196,12 +196,12 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(nitems(dump_avail) * sizeof(uint64_t));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		/* Clear out undumpable pages now if needed */
 		if (vm_phys_is_dumpable(pa))
 			dumpsize += PAGE_SIZE;
 		else
-			dump_drop_page(pa);
+			vm_page_dump_drop(state->dump_bitset, pa);
 	}
 	dumpsize += PAGE_SIZE;
 
@@ -255,7 +255,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 		goto fail;
 
 	/* Dump bitmap */
-	error = blk_write(di, (char *)vm_page_dump, 0,
+	error = blk_write(di, (char *)state->dump_bitset, 0,
 	    round_page(BITSET_SIZE(vm_page_dump_pages)));
 	if (error)
 		goto fail;
@@ -279,7 +279,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	}
 
 	/* Dump memory chunks */
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		if (!count) {
 			prev_pa = pa;
 			count++;
diff --git a/sys/arm64/arm64/minidump_machdep.c b/sys/arm64/arm64/minidump_machdep.c
index 5a935d3c379d..8383d69fc5f8 100644
--- a/sys/arm64/arm64/minidump_machdep.c
+++ b/sys/arm64/arm64/minidump_machdep.c
@@ -187,14 +187,16 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 			for (i = 0; i < Ln_ENTRIES * Ln_ENTRIES;
 			    i++, pa += PAGE_SIZE)
 				if (vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 			pmapsize += (Ln_ENTRIES - 1) * PAGE_SIZE;
 			va += L1_SIZE - L2_SIZE;
 		} else if ((l2e & ATTR_DESCR_MASK) == L2_BLOCK) {
 			pa = l2e & ~ATTR_MASK;
 			for (i = 0; i < Ln_ENTRIES; i++, pa += PAGE_SIZE) {
 				if (vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 			}
 		} else if ((l2e & ATTR_DESCR_MASK) == L2_TABLE) {
 			for (i = 0; i < Ln_ENTRIES; i++) {
@@ -202,9 +204,9 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 				if ((l3e & ATTR_DESCR_MASK) != L3_PAGE)
 					continue;
 				pa = l3e & ~ATTR_MASK;
-				pa = l3e & ~ATTR_MASK;
 				if (PHYS_IN_DMAP(pa) && vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 			}
 		}
 	}
@@ -215,11 +217,11 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		if (PHYS_IN_DMAP(pa) && vm_phys_is_dumpable(pa))
 			dumpsize += PAGE_SIZE;
 		else
-			dump_drop_page(pa);
+			vm_page_dump_drop(state->dump_bitset, pa);
 	}
 	dumpsize += PAGE_SIZE;
 
@@ -270,7 +272,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 		goto fail;
 
 	/* Dump bitmap */
-	error = blk_write(di, (char *)vm_page_dump, 0,
+	error = blk_write(di, (char *)state->dump_bitset, 0,
 	    round_page(BITSET_SIZE(vm_page_dump_pages)));
 	if (error)
 		goto fail;
@@ -351,7 +353,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	}
 
 	/* Dump memory chunks */
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		error = blk_write(di, 0, pa, PAGE_SIZE);
 		if (error)
 			goto fail;
diff --git a/sys/i386/i386/minidump_machdep_base.c b/sys/i386/i386/minidump_machdep_base.c
index 196c375bec56..a3f09228fa2d 100644
--- a/sys/i386/i386/minidump_machdep_base.c
+++ b/sys/i386/i386/minidump_machdep_base.c
@@ -191,7 +191,8 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 			pa = pde & PG_PS_FRAME;
 			for (k = 0; k < NPTEPG; k++) {
 				if (vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 				pa += PAGE_SIZE;
 			}
 			continue;
@@ -204,7 +205,8 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 				if ((pte & PG_V) == PG_V) {
 					pa = pte & PG_FRAME;
 					if (vm_phys_is_dumpable(pa))
-						dump_add_page(pa);
+						vm_page_dump_add(
+						    state->dump_bitset, pa);
 				}
 			}
 		} else {
@@ -218,12 +220,12 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		/* Clear out undumpable pages now if needed */
 		if (vm_phys_is_dumpable(pa)) {
 			dumpsize += PAGE_SIZE;
 		} else {
-			dump_drop_page(pa);
+			vm_page_dump_drop(state->dump_bitset, pa);
 		}
 	}
 	dumpsize += PAGE_SIZE;
@@ -317,7 +319,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	}
 
 	/* Dump memory chunks */
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		error = blk_write(di, 0, pa, PAGE_SIZE);
 		if (error)
 			goto fail;
diff --git a/sys/mips/mips/minidump_machdep.c b/sys/mips/mips/minidump_machdep.c
index 49a5ee3f15a7..abe45e999f13 100644
--- a/sys/mips/mips/minidump_machdep.c
+++ b/sys/mips/mips/minidump_machdep.c
@@ -134,7 +134,8 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 			if (pte_test(&pte[i], PTE_V)) {
 				pa = TLBLO_PTE_TO_PA(pte[i]);
 				if (vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 			}
 		}
 	}
@@ -145,7 +146,7 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	 */
 	for (pa = 0; pa < phys_avail[0]; pa += PAGE_SIZE) {
 		if (vm_phys_is_dumpable(pa))
-			dump_add_page(pa);
+			vm_page_dump_add(state->dump_bitset, pa);
 	}
 
 	/* Calculate dump size. */
@@ -154,12 +155,12 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(nitems(dump_avail) * sizeof(uint64_t));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		/* Clear out undumpable pages now if needed */
 		if (vm_phys_is_dumpable(pa))
 			dumpsize += PAGE_SIZE;
 		else
-			dump_drop_page(pa);
+			vm_page_dump_drop(state->dump_bitset, pa);
 	}
 	dumpsize += PAGE_SIZE;
 
@@ -249,8 +250,8 @@ cpu_minidumpsys(struct dumperinfo *di, const struct minidumpstate *state)
 		prev_pte = 0;
 	}
 
-	/* Dump memory chunks  page by page*/
-	VM_PAGE_DUMP_FOREACH(pa) {
+	/* Dump memory chunks page by page */
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		dump_va = pmap_kenter_temporary(pa, 0);
 		error = write_buffer(di, dump_va, PAGE_SIZE);
 		if (error)
diff --git a/sys/powerpc/aim/mmu_oea64.c b/sys/powerpc/aim/mmu_oea64.c
index 2f7f6ce29422..41771c3650f3 100644
--- a/sys/powerpc/aim/mmu_oea64.c
+++ b/sys/powerpc/aim/mmu_oea64.c
@@ -438,7 +438,7 @@ static int moea64_map_user_ptr(pmap_t pm,
     volatile const void *uaddr, void **kaddr, size_t ulen, size_t *klen);
 static int moea64_decode_kernel_ptr(vm_offset_t addr,
     int *is_user, vm_offset_t *decoded_addr);
-static size_t moea64_scan_pmap(void);
+static size_t moea64_scan_pmap(struct bitset *dump_bitset);
 static void *moea64_dump_pmap_init(unsigned blkpgs);
 #ifdef __powerpc64__
 static void moea64_page_array_startup(long);
@@ -3324,7 +3324,7 @@ moea64_scan_init()
 #ifdef __powerpc64__
 
 static size_t
-moea64_scan_pmap()
+moea64_scan_pmap(struct bitset *dump_bitset)
 {
 	struct pvo_entry *pvo;
 	vm_paddr_t pa, pa_end;
@@ -3367,11 +3367,11 @@ moea64_scan_pmap()
 			pa_end = pa + lpsize;
 			for (; pa < pa_end; pa += PAGE_SIZE) {
 				if (vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(dump_bitset, pa);
 			}
 		} else {
 			if (vm_phys_is_dumpable(pa))
-				dump_add_page(pa);
+				vm_page_dump_add(dump_bitset, pa);
 		}
 	}
 	PMAP_UNLOCK(kernel_pmap);
@@ -3393,7 +3393,7 @@ moea64_dump_pmap_init(unsigned blkpgs)
 #else
 
 static size_t
-moea64_scan_pmap()
+moea64_scan_pmap(struct bitset *dump_bitset __unused)
 {
 	return (0);
 }
diff --git a/sys/powerpc/include/dump.h b/sys/powerpc/include/dump.h
index 3debbfbe25f9..c45ccd2158de 100644
--- a/sys/powerpc/include/dump.h
+++ b/sys/powerpc/include/dump.h
@@ -40,7 +40,7 @@
 
 void dumpsys_pa_init(void);
 void dumpsys_unmap_chunk(vm_paddr_t, size_t, void *);
-size_t dumpsys_scan_pmap(void);
+size_t dumpsys_scan_pmap(struct bitset *);
 void *dumpsys_dump_pmap_init(unsigned blkpgs);
 void *dumpsys_dump_pmap(void *ctx, void *buf, u_long *nbytes);
 
diff --git a/sys/powerpc/include/mmuvar.h b/sys/powerpc/include/mmuvar.h
index f94ca56df441..b449064e009f 100644
--- a/sys/powerpc/include/mmuvar.h
+++ b/sys/powerpc/include/mmuvar.h
@@ -96,7 +96,7 @@ typedef	void	(*pmap_sync_icache_t)(pmap_t, vm_offset_t, vm_size_t);
 typedef	void	(*pmap_dumpsys_map_chunk_t)(vm_paddr_t, size_t, void **);
 typedef	void	(*pmap_dumpsys_unmap_chunk_t)(vm_paddr_t, size_t, void *);
 typedef	void	(*pmap_dumpsys_pa_init_t)(void);
-typedef	size_t	(*pmap_dumpsys_scan_pmap_t)(void);
+typedef	size_t	(*pmap_dumpsys_scan_pmap_t)(struct bitset *dump_bitset);
 typedef	void	*(*pmap_dumpsys_dump_pmap_init_t)(unsigned);
 typedef	void	*(*pmap_dumpsys_dump_pmap_t)(void *, void *, u_long *);
 typedef	vm_offset_t	(*pmap_quick_enter_page_t)(vm_page_t);
diff --git a/sys/powerpc/powerpc/minidump_machdep.c b/sys/powerpc/powerpc/minidump_machdep.c
index c7e8d1965b98..396c6487823e 100644
--- a/sys/powerpc/powerpc/minidump_machdep.c
+++ b/sys/powerpc/powerpc/minidump_machdep.c
@@ -204,7 +204,7 @@ retry:
 	DBG(total = dumptotal = 0;)
 
 	/* Build set of dumpable pages from kernel pmap */
-	pmapsize = dumpsys_scan_pmap();
+	pmapsize = dumpsys_scan_pmap(state->dump_bitset);
 	if (pmapsize % PAGE_SIZE != 0) {
 		printf("pmapsize not page aligned: 0x%x\n", pmapsize);
 		return (EINVAL);
@@ -217,12 +217,12 @@ retry:
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
 	dumpsize += pmapsize;
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		/* Clear out undumpable pages now if needed */
 		if (vm_phys_is_dumpable(pa))
 			dumpsize += PAGE_SIZE;
 		else
-			dump_drop_page(pa);
+			vm_page_dump_drop(state->dump_bitset, pa);
 	}
 	dumpsys_pb_init(dumpsize);
 
@@ -289,7 +289,7 @@ retry:
 	dump_total("pmap", pmapsize);
 
 	/* Dump memory chunks */
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		error = blk_write(di, 0, pa, PAGE_SIZE);
 		if (error)
 			goto fail;
diff --git a/sys/powerpc/powerpc/pmap_dispatch.c b/sys/powerpc/powerpc/pmap_dispatch.c
index 5a47b6d8bf31..a3c227bbde7d 100644
--- a/sys/powerpc/powerpc/pmap_dispatch.c
+++ b/sys/powerpc/powerpc/pmap_dispatch.c
@@ -188,7 +188,7 @@ DEFINE_PMAP_IFUNC(void, tlbie_all, (void));
 DEFINE_DUMPSYS_IFUNC(void, map_chunk, (vm_paddr_t, size_t, void **));
 DEFINE_DUMPSYS_IFUNC(void, unmap_chunk, (vm_paddr_t, size_t, void *));
 DEFINE_DUMPSYS_IFUNC(void, pa_init, (void));
-DEFINE_DUMPSYS_IFUNC(size_t, scan_pmap, (void));
+DEFINE_DUMPSYS_IFUNC(size_t, scan_pmap, (struct bitset *));
 DEFINE_DUMPSYS_IFUNC(void *, dump_pmap_init, (unsigned));
 DEFINE_DUMPSYS_IFUNC(void *, dump_pmap, (void *, void *, u_long *));
 
diff --git a/sys/riscv/riscv/minidump_machdep.c b/sys/riscv/riscv/minidump_machdep.c
index 814c2dd00697..ee6faaa6680f 100644
--- a/sys/riscv/riscv/minidump_machdep.c
+++ b/sys/riscv/riscv/minidump_machdep.c
@@ -197,7 +197,8 @@ retry:
 			pa = (l2e >> PTE_PPN1_S) << L2_SHIFT;
 			for (i = 0; i < Ln_ENTRIES; i++, pa += PAGE_SIZE) {
 				if (vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 			}
 		} else {
 			for (i = 0; i < Ln_ENTRIES; i++) {
@@ -206,7 +207,8 @@ retry:
 					continue;
 				pa = (l3e >> PTE_PPN0_S) * PAGE_SIZE;
 				if (PHYS_IN_DMAP(pa) && vm_phys_is_dumpable(pa))
-					dump_add_page(pa);
+					vm_page_dump_add(state->dump_bitset,
+					    pa);
 			}
 		}
 	}
@@ -217,12 +219,12 @@ retry:
 	dumpsize += round_page(mbp->msg_size);
 	dumpsize += round_page(sizeof(dump_avail));
 	dumpsize += round_page(BITSET_SIZE(vm_page_dump_pages));
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		/* Clear out undumpable pages now if needed */
 		if (PHYS_IN_DMAP(pa) && vm_phys_is_dumpable(pa))
 			dumpsize += PAGE_SIZE;
 		else
-			dump_drop_page(pa);
+			vm_page_dump_drop(state->dump_bitset, pa);
 	}
 	dumpsize += PAGE_SIZE;
 
@@ -327,7 +329,7 @@ retry:
 
 	/* Dump memory chunks */
 	/* XXX cluster it up and use blk_dump() */
-	VM_PAGE_DUMP_FOREACH(pa) {
+	VM_PAGE_DUMP_FOREACH(state->dump_bitset, pa) {
 		error = blk_write(di, 0, pa, PAGE_SIZE);
 		if (error)
 			goto fail;
diff --git a/sys/vm/vm_dumpset.h b/sys/vm/vm_dumpset.h
index 6be417344263..f9ba6b2429c5 100644
--- a/sys/vm/vm_dumpset.h
+++ b/sys/vm/vm_dumpset.h
@@ -37,8 +37,12 @@ extern struct bitset *vm_page_dump;
 extern long vm_page_dump_pages;
 extern vm_paddr_t dump_avail[PHYS_AVAIL_COUNT];
 
+/* For the common case: add/remove a page from the minidump bitset. */
+#define	dump_add_page(pa)	vm_page_dump_add(vm_page_dump, pa)
+#define	dump_drop_page(pa)	vm_page_dump_drop(vm_page_dump, pa)
+
 static inline void
-dump_add_page(vm_paddr_t pa)
+vm_page_dump_add(struct bitset *bitset, vm_paddr_t pa)
 {
 	vm_pindex_t adj;
 	int i;
@@ -48,7 +52,7 @@ dump_add_page(vm_paddr_t pa)
 		if (pa >= dump_avail[i] && pa < dump_avail[i + 1]) {
 			BIT_SET_ATOMIC(vm_page_dump_pages,
 			    (pa >> PAGE_SHIFT) - (dump_avail[i] >> PAGE_SHIFT) +
-			    adj, vm_page_dump);
+			    adj, bitset);
 			return;
 		}
 		adj += howmany(dump_avail[i + 1], PAGE_SIZE) -
@@ -57,7 +61,7 @@ dump_add_page(vm_paddr_t pa)
 }
 
 static inline void
-dump_drop_page(vm_paddr_t pa)
+vm_page_dump_drop(struct bitset *bitset, vm_paddr_t pa)
 {
 	vm_pindex_t adj;
 	int i;
@@ -67,7 +71,7 @@ dump_drop_page(vm_paddr_t pa)
 		if (pa >= dump_avail[i] && pa < dump_avail[i + 1]) {
 			BIT_CLR_ATOMIC(vm_page_dump_pages,
 			    (pa >> PAGE_SHIFT) - (dump_avail[i] >> PAGE_SHIFT) +
-			    adj, vm_page_dump);
+			    adj, bitset);
 			return;
 		}
 		adj += howmany(dump_avail[i + 1], PAGE_SIZE) -
@@ -91,9 +95,9 @@ vm_page_dump_index_to_pa(int bit)
 	return ((vm_paddr_t)NULL);
 }
 
-#define VM_PAGE_DUMP_FOREACH(pa)						\
-	for (vm_pindex_t __b = BIT_FFS(vm_page_dump_pages, vm_page_dump);	\
-	    (pa) = vm_page_dump_index_to_pa(__b - 1), __b != 0;			\
-	    __b = BIT_FFS_AT(vm_page_dump_pages, vm_page_dump, __b))
+#define VM_PAGE_DUMP_FOREACH(bitset, pa)				\
+	for (vm_pindex_t __b = BIT_FFS(vm_page_dump_pages, bitset);	\
+	    (pa) = vm_page_dump_index_to_pa(__b - 1), __b != 0;		\
+	    __b = BIT_FFS_AT(vm_page_dump_pages, bitset, __b))
 
 #endif	/* _SYS_DUMPSET_H_ */