DLPX-44812 integrate EP-220 large memory scalability

11 files changed, 235 insertions, 55 deletions

diff --git a/include/sys/Makefile.am b/include/sys/Makefile.am
index 37df6e1d2..956643801 100644
--- a/include/sys/Makefile.am
+++ b/include/sys/Makefile.am
@@ -1,6 +1,7 @@
 SUBDIRS = fm fs crypto sysevent
 
 COMMON_H = \
+	$(top_srcdir)/include/sys/abd.h \
 	$(top_srcdir)/include/sys/arc.h \
 	$(top_srcdir)/include/sys/arc_impl.h \
 	$(top_srcdir)/include/sys/avl.h \
diff --git a/include/sys/abd.h b/include/sys/abd.h
new file mode 100644
index 000000000..43aaa7a15
--- /dev/null
+++ b/include/sys/abd.h
@@ -0,0 +1,160 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright (c) 2014 by Chunwei Chen. All rights reserved.
+ * Copyright (c) 2016 by Delphix. All rights reserved.
+ */
+
+#ifndef _ABD_H
+#define	_ABD_H
+
+#include <sys/isa_defs.h>
+#include <sys/int_types.h>
+#include <sys/debug.h>
+#include <sys/refcount.h>
+#ifdef _KERNEL
+#include <linux/mm.h>
+#include <sys/uio.h>
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum abd_flags {
+	ABD_FLAG_LINEAR	= 1 << 0,	/* is buffer linear (or scattered)? */
+	ABD_FLAG_OWNER	= 1 << 1,	/* does it own its data buffers? */
+	ABD_FLAG_META	= 1 << 2	/* does this represent FS metadata? */
+} abd_flags_t;
+
+typedef struct abd {
+	abd_flags_t	abd_flags;
+	uint_t		abd_size;	/* excludes scattered abd_offset */
+	struct abd	*abd_parent;
+	refcount_t	abd_children;
+	union {
+		struct abd_scatter {
+			uint_t		abd_offset;
+			uint_t		abd_chunk_size;
+			struct page	*abd_chunks[];
+		} abd_scatter;
+		struct abd_linear {
+			void		*abd_buf;
+		} abd_linear;
+	} abd_u;
+} abd_t;
+
+typedef int abd_iter_func_t(void *buf, size_t len, void *private);
+typedef int abd_iter_func2_t(void *bufa, void *bufb, size_t len, void *private);
+
+extern int zfs_abd_scatter_enabled;
+
+static inline boolean_t
+abd_is_linear(abd_t *abd)
+{
+	return ((abd->abd_flags & ABD_FLAG_LINEAR) != 0);
+}
+
+/*
+ * Allocations and deallocations
+ */
+
+abd_t *abd_alloc(size_t, boolean_t);
+abd_t *abd_alloc_linear(size_t, boolean_t);
+abd_t *abd_alloc_for_io(size_t, boolean_t);
+abd_t *abd_alloc_sametype(abd_t *, size_t);
+void abd_free(abd_t *);
+abd_t *abd_get_offset(abd_t *, size_t);
+abd_t *abd_get_from_buf(void *, size_t);
+void abd_put(abd_t *);
+
+/*
+ * Conversion to and from a normal buffer
+ */
+
+void *abd_to_buf(abd_t *);
+void *abd_borrow_buf(abd_t *, size_t);
+void *abd_borrow_buf_copy(abd_t *, size_t);
+void abd_return_buf(abd_t *, void *, size_t);
+void abd_return_buf_copy(abd_t *, void *, size_t);
+void abd_take_ownership_of_buf(abd_t *, boolean_t);
+void abd_release_ownership_of_buf(abd_t *);
+
+/*
+ * ABD operations
+ */
+
+int abd_iterate_func(abd_t *, size_t, size_t, abd_iter_func_t *, void *);
+int abd_iterate_func2(abd_t *, abd_t *, size_t, size_t, size_t,
+    abd_iter_func2_t *, void *);
+void abd_copy_off(abd_t *, abd_t *, size_t, size_t, size_t);
+void abd_copy_from_buf_off(abd_t *, const void *, size_t, size_t);
+void abd_copy_to_buf_off(void *, abd_t *, size_t, size_t);
+int abd_cmp(abd_t *, abd_t *);
+int abd_cmp_buf_off(abd_t *, const void *, size_t, size_t);
+void abd_zero_off(abd_t *, size_t, size_t);
+
+/*
+ * Wrappers for calls with offsets of 0
+ */
+
+static inline void
+abd_copy(abd_t *dabd, abd_t *sabd, size_t size)
+{
+	abd_copy_off(dabd, sabd, 0, 0, size);
+}
+
+static inline void
+abd_copy_from_buf(abd_t *abd, void *buf, size_t size)
+{
+	abd_copy_from_buf_off(abd, buf, 0, size);
+}
+
+static inline void
+abd_copy_to_buf(void* buf, abd_t *abd, size_t size)
+{
+	abd_copy_to_buf_off(buf, abd, 0, size);
+}
+
+static inline int
+abd_cmp_buf(abd_t *abd, void *buf, size_t size)
+{
+	return (abd_cmp_buf_off(abd, buf, 0, size));
+}
+
+static inline void
+abd_zero(abd_t *abd, size_t size)
+{
+	abd_zero_off(abd, 0, size);
+}
+
+/*
+ * Module lifecycle
+ */
+
+void abd_init(void);
+void abd_fini(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* _ABD_H */
diff --git a/include/sys/arc_impl.h b/include/sys/arc_impl.h
index d2dc527fe..f5b7cb42a 100644
--- a/include/sys/arc_impl.h
+++ b/include/sys/arc_impl.h
@@ -166,7 +166,7 @@ typedef struct l1arc_buf_hdr {
 	refcount_t		b_refcnt;
 
 	arc_callback_t		*b_acb;
-	void			*b_pdata;
+	abd_t			*b_pabd;
 } l1arc_buf_hdr_t;
 
 typedef struct l2arc_dev {
diff --git a/include/sys/ddt.h b/include/sys/ddt.h
index 3befcb844..667795f96 100644
--- a/include/sys/ddt.h
+++ b/include/sys/ddt.h
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016 by Delphix. All rights reserved.
  */
 
 #ifndef _SYS_DDT_H
@@ -35,6 +36,8 @@
 extern "C" {
 #endif
 
+struct abd;
+
 /*
  * On-disk DDT formats, in the desired search order (newest version first).
  */
@@ -108,7 +111,7 @@ struct ddt_entry {
 	ddt_key_t	dde_key;
 	ddt_phys_t	dde_phys[DDT_PHYS_TYPES];
 	zio_t		*dde_lead_zio[DDT_PHYS_TYPES];
-	void		*dde_repair_data;
+	struct abd	*dde_repair_abd;
 	enum ddt_type	dde_type;
 	enum ddt_class	dde_class;
 	uint8_t		dde_loading;
diff --git a/include/sys/spa.h b/include/sys/spa.h
index 3d0b962e6..c35128c0d 100644
--- a/include/sys/spa.h
+++ b/include/sys/spa.h
@@ -416,15 +416,17 @@ _NOTE(CONSTCOND) } while (0)
 
 #define	BP_GET_FILL(bp) (BP_IS_EMBEDDED(bp) ? 1 : (bp)->blk_fill)
 
+#define	BP_IS_METADATA(bp)	\
+	(BP_GET_LEVEL(bp) > 0 || DMU_OT_IS_METADATA(BP_GET_TYPE(bp)))
+
 #define	BP_GET_ASIZE(bp)	\
 	(BP_IS_EMBEDDED(bp) ? 0 : \
 	DVA_GET_ASIZE(&(bp)->blk_dva[0]) + \
 	DVA_GET_ASIZE(&(bp)->blk_dva[1]) + \
 	DVA_GET_ASIZE(&(bp)->blk_dva[2]))
 
-#define	BP_GET_UCSIZE(bp) \
-	((BP_GET_LEVEL(bp) > 0 || DMU_OT_IS_METADATA(BP_GET_TYPE(bp))) ? \
-	BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp))
+#define	BP_GET_UCSIZE(bp)	\
+	(BP_IS_METADATA(bp) ? BP_GET_PSIZE(bp) : BP_GET_LSIZE(bp))
 
 #define	BP_GET_NDVAS(bp)	\
 	(BP_IS_EMBEDDED(bp) ? 0 : \
@@ -569,8 +571,7 @@ _NOTE(CONSTCOND) } while (0)
 }
 
 #define	BP_GET_BUFC_TYPE(bp)						\
-	(((BP_GET_LEVEL(bp) > 0) || (DMU_OT_IS_METADATA(BP_GET_TYPE(bp)))) ? \
-	ARC_BUFC_METADATA : ARC_BUFC_DATA)
+	(BP_IS_METADATA(bp) ? ARC_BUFC_METADATA : ARC_BUFC_DATA)
 
 typedef enum spa_import_type {
 	SPA_IMPORT_EXISTING,
diff --git a/include/sys/vdev_impl.h b/include/sys/vdev_impl.h
index b9a2d181b..d7f11a2b8 100644
--- a/include/sys/vdev_impl.h
+++ b/include/sys/vdev_impl.h
@@ -53,6 +53,7 @@ extern "C" {
 typedef struct vdev_queue vdev_queue_t;
 typedef struct vdev_cache vdev_cache_t;
 typedef struct vdev_cache_entry vdev_cache_entry_t;
+struct abd;
 
 extern int zfs_vdev_queue_depth_pct;
 extern uint32_t zfs_vdev_async_write_max_active;
@@ -87,7 +88,7 @@ typedef const struct vdev_ops {
  * Virtual device properties
  */
 struct vdev_cache_entry {
-	char		*ve_data;
+	struct abd	*ve_abd;
 	uint64_t	ve_offset;
 	clock_t		ve_lastused;
 	avl_node_t	ve_offset_node;
diff --git a/include/sys/vdev_raidz_impl.h b/include/sys/vdev_raidz_impl.h
index 735b67764..b4663b97c 100644
--- a/include/sys/vdev_raidz_impl.h
+++ b/include/sys/vdev_raidz_impl.h
@@ -28,6 +28,7 @@
 #include <sys/types.h>
 #include <sys/debug.h>
 #include <sys/kstat.h>
+#include <sys/abd.h>
 
 #ifdef  __cplusplus
 extern "C" {
@@ -104,7 +105,7 @@ typedef struct raidz_col {
 	size_t rc_devidx;		/* child device index for I/O */
 	size_t rc_offset;		/* device offset */
 	size_t rc_size;			/* I/O size */
-	void *rc_data;			/* I/O data */
+	abd_t *rc_abd;			/* I/O data */
 	void *rc_gdata;			/* used to store the "good" version */
 	int rc_error;			/* I/O error for this device */
 	unsigned int rc_tried;		/* Did we attempt this I/O column? */
@@ -121,7 +122,7 @@ typedef struct raidz_map {
 	size_t rm_firstdatacol;		/* First data column/parity count */
 	size_t rm_nskip;		/* Skipped sectors for padding */
 	size_t rm_skipstart;		/* Column index of padding start */
-	void *rm_datacopy;		/* rm_asize-buffer of copied data */
+	abd_t *rm_abd_copy;		/* rm_asize-buffer of copied data */
 	size_t rm_reports;		/* # of referencing checksum reports */
 	unsigned int rm_freed;		/* map no longer has referencing ZIO */
 	unsigned int rm_ecksuminjected;	/* checksum error was injected */
diff --git a/include/sys/zio.h b/include/sys/zio.h
index 864e8b2be..6c5153dcf 100644
--- a/include/sys/zio.h
+++ b/include/sys/zio.h
@@ -301,6 +301,7 @@ typedef void zio_cksum_free_f(void *cbdata, size_t size);
 
 struct zio_bad_cksum;				/* defined in zio_checksum.h */
 struct dnode_phys;
+struct abd;
 
 struct zio_cksum_report {
 	struct zio_cksum_report *zcr_next;
@@ -333,12 +334,12 @@ typedef struct zio_gang_node {
 } zio_gang_node_t;
 
 typedef zio_t *zio_gang_issue_func_t(zio_t *zio, blkptr_t *bp,
-    zio_gang_node_t *gn, void *data);
+    zio_gang_node_t *gn, struct abd *data, uint64_t offset);
 
-typedef void zio_transform_func_t(zio_t *zio, void *data, uint64_t size);
+typedef void zio_transform_func_t(zio_t *zio, struct abd *data, uint64_t size);
 
 typedef struct zio_transform {
-	void			*zt_orig_data;
+	struct abd		*zt_orig_abd;
 	uint64_t		zt_orig_size;
 	uint64_t		zt_bufsize;
 	zio_transform_func_t	*zt_transform;
@@ -396,8 +397,8 @@ struct zio {
 	uint64_t	io_lsize;
 
 	/* Data represented by this I/O */
-	void		*io_data;
-	void		*io_orig_data;
+	struct abd	*io_abd;
+	struct abd	*io_orig_abd;
 	uint64_t	io_size;
 	uint64_t	io_orig_size;
 
@@ -455,19 +456,19 @@ extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
 extern zio_t *zio_root(spa_t *spa,
     zio_done_func_t *done, void *private, enum zio_flag flags);
 
-extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp, void *data,
-    uint64_t lsize, zio_done_func_t *done, void *private,
+extern zio_t *zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
+    struct abd *data, uint64_t lsize, zio_done_func_t *done, void *private,
     zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb);
 
 extern zio_t *zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
-    void *data, uint64_t size, uint64_t psize, const zio_prop_t *zp,
+    struct abd *data, uint64_t size, uint64_t psize, const zio_prop_t *zp,
     zio_done_func_t *ready, zio_done_func_t *children_ready,
     zio_done_func_t *physdone, zio_done_func_t *done,
     void *private, zio_priority_t priority, enum zio_flag flags,
     const zbookmark_phys_t *zb);
 
 extern zio_t *zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
-    void *data, uint64_t size, zio_done_func_t *done, void *private,
+    struct abd *data, uint64_t size, zio_done_func_t *done, void *private,
     zio_priority_t priority, enum zio_flag flags, zbookmark_phys_t *zb);
 
 extern void zio_write_override(zio_t *zio, blkptr_t *bp, int copies,
@@ -483,12 +484,12 @@ extern zio_t *zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
     zio_done_func_t *done, void *private, enum zio_flag flags);
 
 extern zio_t *zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
-    uint64_t size, void *data, int checksum,
+    uint64_t size, struct abd *data, int checksum,
     zio_done_func_t *done, void *private, zio_priority_t priority,
     enum zio_flag flags, boolean_t labels);
 
 extern zio_t *zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset,
-    uint64_t size, void *data, int checksum,
+    uint64_t size, struct abd *data, int checksum,
     zio_done_func_t *done, void *private, zio_priority_t priority,
     enum zio_flag flags, boolean_t labels);
 
@@ -517,21 +518,20 @@ extern void *zio_buf_alloc(size_t size);
 extern void zio_buf_free(void *buf, size_t size);
 extern void *zio_data_buf_alloc(size_t size);
 extern void zio_data_buf_free(void *buf, size_t size);
-extern void *zio_buf_alloc_flags(size_t size, int flags);
 
-extern void zio_push_transform(zio_t *zio, void *data, uint64_t size,
+extern void zio_push_transform(zio_t *zio, struct abd *abd, uint64_t size,
     uint64_t bufsize, zio_transform_func_t *transform);
 extern void zio_pop_transforms(zio_t *zio);
 
 extern void zio_resubmit_stage_async(void *);
 
 extern zio_t *zio_vdev_child_io(zio_t *zio, blkptr_t *bp, vdev_t *vd,
-    uint64_t offset, void *data, uint64_t size, int type,
+    uint64_t offset, struct abd *data, uint64_t size, int type,
     zio_priority_t priority, enum zio_flag flags,
     zio_done_func_t *done, void *private);
 
 extern zio_t *zio_vdev_delegated_io(vdev_t *vd, uint64_t offset,
-    void *data, uint64_t size, int type, zio_priority_t priority,
+    struct abd *data, uint64_t size, int type, zio_priority_t priority,
     enum zio_flag flags, zio_done_func_t *done, void *private);
 
 extern void zio_vdev_io_bypass(zio_t *zio);
diff --git a/include/sys/zio_checksum.h b/include/sys/zio_checksum.h
index b4c2c8c08..a6cafc9b2 100644
--- a/include/sys/zio_checksum.h
+++ b/include/sys/zio_checksum.h
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2014, 2015 by Delphix. All rights reserved.
+ * Copyright (c) 2014, 2016 by Delphix. All rights reserved.
  * Copyright Saso Kiselkov 2013, All rights reserved.
  */
 
@@ -34,12 +34,12 @@
 extern "C" {
 #endif
 
+struct abd;
+
 /*
  * Signature for checksum functions.
  */
-typedef void zio_checksum_func_t(const void *, uint64_t, const void *,
-    zio_cksum_t *);
-typedef void zio_checksum_t(const void *data, uint64_t size,
+typedef void zio_checksum_t(struct abd *abd, uint64_t size,
     const void *ctx_template, zio_cksum_t *zcp);
 typedef void *zio_checksum_tmpl_init_t(const zio_cksum_salt_t *salt);
 typedef void zio_checksum_tmpl_free_t(void *ctx_template);
@@ -83,28 +83,28 @@ extern zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS];
 /*
  * Checksum routines.
  */
-extern zio_checksum_t zio_checksum_SHA256;
-extern zio_checksum_t zio_checksum_SHA512_native;
-extern zio_checksum_t zio_checksum_SHA512_byteswap;
+extern zio_checksum_t abd_checksum_SHA256;
+extern zio_checksum_t abd_checksum_SHA512_native;
+extern zio_checksum_t abd_checksum_SHA512_byteswap;
 
 /* Skein */
-extern zio_checksum_t zio_checksum_skein_native;
-extern zio_checksum_t zio_checksum_skein_byteswap;
-extern zio_checksum_tmpl_init_t zio_checksum_skein_tmpl_init;
-extern zio_checksum_tmpl_free_t zio_checksum_skein_tmpl_free;
+extern zio_checksum_t abd_checksum_skein_native;
+extern zio_checksum_t abd_checksum_skein_byteswap;
+extern zio_checksum_tmpl_init_t abd_checksum_skein_tmpl_init;
+extern zio_checksum_tmpl_free_t abd_checksum_skein_tmpl_free;
 
 /* Edon-R */
-extern zio_checksum_t zio_checksum_edonr_native;
-extern zio_checksum_t zio_checksum_edonr_byteswap;
-extern zio_checksum_tmpl_init_t zio_checksum_edonr_tmpl_init;
-extern zio_checksum_tmpl_free_t zio_checksum_edonr_tmpl_free;
+extern zio_checksum_t abd_checksum_edonr_native;
+extern zio_checksum_t abd_checksum_edonr_byteswap;
+extern zio_checksum_tmpl_init_t abd_checksum_edonr_tmpl_init;
+extern zio_checksum_tmpl_free_t abd_checksum_edonr_tmpl_free;
 
 extern int zio_checksum_equal(spa_t *, blkptr_t *, enum zio_checksum,
     void *, uint64_t, uint64_t, zio_bad_cksum_t *);
-extern void zio_checksum_compute(zio_t *zio, enum zio_checksum checksum,
-    void *data, uint64_t size);
+extern void zio_checksum_compute(zio_t *, enum zio_checksum,
+    struct abd *, uint64_t);
 extern int zio_checksum_error_impl(spa_t *, blkptr_t *, enum zio_checksum,
-    void *, uint64_t, uint64_t, zio_bad_cksum_t *);
+    struct abd *, uint64_t, uint64_t, zio_bad_cksum_t *);
 extern int zio_checksum_error(zio_t *zio, zio_bad_cksum_t *out);
 extern enum zio_checksum spa_dedup_checksum(spa_t *spa);
 extern void zio_checksum_templates_free(spa_t *spa);
diff --git a/include/sys/zio_compress.h b/include/sys/zio_compress.h
index da58ef7aa..1642823d3 100644
--- a/include/sys/zio_compress.h
+++ b/include/sys/zio_compress.h
@@ -22,12 +22,14 @@
 /*
  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
- * Copyright (c) 2015 by Delphix. All rights reserved.
+ * Copyright (c) 2015, 2016 by Delphix. All rights reserved.
  */
 
 #ifndef _SYS_ZIO_COMPRESS_H
 #define	_SYS_ZIO_COMPRESS_H
 
+#include <sys/abd.h>
+
 #ifdef	__cplusplus
 extern "C" {
 #endif
@@ -60,13 +62,20 @@ typedef int zio_decompress_func_t(void *src, void *dst,
     size_t s_len, size_t d_len, int);
 
 /*
+ * Common signature for all zio decompress functions using an ABD as input.
+ * This is helpful if you have both compressed ARC and scatter ABDs enabled,
+ * but is not a requirement for all compression algorithms.
+ */
+typedef int zio_decompress_abd_func_t(abd_t *src, void *dst,
+    size_t s_len, size_t d_len, int);
+/*
  * Information about each compression function.
  */
 typedef const struct zio_compress_info {
-	zio_compress_func_t	*ci_compress;	/* compression function */
-	zio_decompress_func_t	*ci_decompress;	/* decompression function */
-	int			ci_level;	/* level parameter */
-	char			*ci_name;	/* algorithm name */
+	char				*ci_name;
+	int				ci_level;
+	zio_compress_func_t		*ci_compress;
+	zio_decompress_func_t		*ci_decompress;
 } zio_compress_info_t;
 
 extern zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS];
@@ -96,13 +105,16 @@ extern size_t lz4_compress_zfs(void *src, void *dst, size_t s_len, size_t d_len,
     int level);
 extern int lz4_decompress_zfs(void *src, void *dst, size_t s_len, size_t d_len,
     int level);
-
+extern int lz4_decompress_abd(abd_t *src, void *dst, size_t s_len, size_t d_len,
+    int level);
 /*
  * Compress and decompress data if necessary.
  */
-extern size_t zio_compress_data(enum zio_compress c, void *src, void *dst,
+extern size_t zio_compress_data(enum zio_compress c, abd_t *src, void *dst,
     size_t s_len);
-extern int zio_decompress_data(enum zio_compress c, void *src, void *dst,
+extern int zio_decompress_data(enum zio_compress c, abd_t *src, void *dst,
+    size_t s_len, size_t d_len);
+extern int zio_decompress_data_buf(enum zio_compress c, void *src, void *dst,
     size_t s_len, size_t d_len);
 
 #ifdef	__cplusplus
diff --git a/include/zfs_fletcher.h b/include/zfs_fletcher.h
index 633606d14..5c7a61c56 100644
--- a/include/zfs_fletcher.h
+++ b/include/zfs_fletcher.h
@@ -48,15 +48,16 @@ extern "C" {
  * checksum method is added. This method will ignore last (size % 4) bytes of
  * the data buffer.
  */
+void fletcher_init(zio_cksum_t *);
 void fletcher_2_native(const void *, uint64_t, const void *, zio_cksum_t *);
 void fletcher_2_byteswap(const void *, uint64_t, const void *, zio_cksum_t *);
 void fletcher_4_native(const void *, uint64_t, const void *, zio_cksum_t *);
+int fletcher_2_incremental_native(void *, size_t, void *);
+int fletcher_2_incremental_byteswap(void *, size_t, void *);
 void fletcher_4_native_varsize(const void *, uint64_t, zio_cksum_t *);
 void fletcher_4_byteswap(const void *, uint64_t, const void *, zio_cksum_t *);
-void fletcher_4_incremental_native(const void *, uint64_t,
-    zio_cksum_t *);
-void fletcher_4_incremental_byteswap(const void *, uint64_t,
-    zio_cksum_t *);
+int fletcher_4_incremental_native(void *, size_t, void *);
+int fletcher_4_incremental_byteswap(void *, size_t, void *);
 int fletcher_4_impl_set(const char *selector);
 void fletcher_4_init(void);
 void fletcher_4_fini(void);