Support custom build directories and move includes

One of the neat tricks an autoconf style project is capable of
is allow configurion/building in a directory other than the
source directory.  The major advantage to this is that you can
build the project various different ways while making changes
in a single source tree.

For example, this project is designed to work on various different
Linux distributions each of which work slightly differently.  This
means that changes need to verified on each of those supported
distributions perferably before the change is committed to the
public git repo.

Using nfs and custom build directories makes this much easier.
I now have a single source tree in nfs mounted on several different
systems each running a supported distribution.  When I make a
change to the source base I suspect may break things I can
concurrently build from the same source on all the systems each
in their own subdirectory.

wget -c http://github.com/downloads/behlendorf/zfs/zfs-x.y.z.tar.gz
tar -xzf zfs-x.y.z.tar.gz
cd zfs-x-y-z

------------------------- run concurrently ----------------------
<ubuntu system>  <fedora system>  <debian system>  <rhel6 system>
mkdir ubuntu     mkdir fedora     mkdir debian     mkdir rhel6
cd ubuntu        cd fedora        cd debian        cd rhel6
../configure     ../configure     ../configure     ../configure
make             make             make             make
make check       make check       make check       make check

This change also moves many of the include headers from individual
incude/sys directories under the modules directory in to a single
top level include directory.  This has the advantage of making
the build rules cleaner and logically it makes a bit more sense.

1 files changed, 743 insertions, 0 deletions

diff --git a/include/sys/dmu.h b/include/sys/dmu.h
new file mode 100644
index 000000000..575cb2d10
--- /dev/null
+++ b/include/sys/dmu.h
@@ -0,0 +1,743 @@
+/*
+ * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ */
+
+/* Portions Copyright 2010 Robert Milkowski */
+
+#ifndef	_SYS_DMU_H
+#define	_SYS_DMU_H
+
+/*
+ * This file describes the interface that the DMU provides for its
+ * consumers.
+ *
+ * The DMU also interacts with the SPA.  That interface is described in
+ * dmu_spa.h.
+ */
+
+#include <sys/inttypes.h>
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/cred.h>
+#include <sys/time.h>
+#include <sys/uio.h>
+#ifdef _KERNEL
+#include <sys/blkdev.h>
+#endif
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+struct page;
+struct vnode;
+struct spa;
+struct zilog;
+struct zio;
+struct blkptr;
+struct zap_cursor;
+struct dsl_dataset;
+struct dsl_pool;
+struct dnode;
+struct drr_begin;
+struct drr_end;
+struct zbookmark;
+struct spa;
+struct nvlist;
+struct arc_buf;
+struct zio_prop;
+struct sa_handle;
+
+typedef struct objset objset_t;
+typedef struct dmu_tx dmu_tx_t;
+typedef struct dsl_dir dsl_dir_t;
+
+typedef enum dmu_object_type {
+	DMU_OT_NONE,
+	/* general: */
+	DMU_OT_OBJECT_DIRECTORY,	/* ZAP */
+	DMU_OT_OBJECT_ARRAY,		/* UINT64 */
+	DMU_OT_PACKED_NVLIST,		/* UINT8 (XDR by nvlist_pack/unpack) */
+	DMU_OT_PACKED_NVLIST_SIZE,	/* UINT64 */
+	DMU_OT_BPOBJ,			/* UINT64 */
+	DMU_OT_BPOBJ_HDR,		/* UINT64 */
+	/* spa: */
+	DMU_OT_SPACE_MAP_HEADER,	/* UINT64 */
+	DMU_OT_SPACE_MAP,		/* UINT64 */
+	/* zil: */
+	DMU_OT_INTENT_LOG,		/* UINT64 */
+	/* dmu: */
+	DMU_OT_DNODE,			/* DNODE */
+	DMU_OT_OBJSET,			/* OBJSET */
+	/* dsl: */
+	DMU_OT_DSL_DIR,			/* UINT64 */
+	DMU_OT_DSL_DIR_CHILD_MAP,	/* ZAP */
+	DMU_OT_DSL_DS_SNAP_MAP,		/* ZAP */
+	DMU_OT_DSL_PROPS,		/* ZAP */
+	DMU_OT_DSL_DATASET,		/* UINT64 */
+	/* zpl: */
+	DMU_OT_ZNODE,			/* ZNODE */
+	DMU_OT_OLDACL,			/* Old ACL */
+	DMU_OT_PLAIN_FILE_CONTENTS,	/* UINT8 */
+	DMU_OT_DIRECTORY_CONTENTS,	/* ZAP */
+	DMU_OT_MASTER_NODE,		/* ZAP */
+	DMU_OT_UNLINKED_SET,		/* ZAP */
+	/* zvol: */
+	DMU_OT_ZVOL,			/* UINT8 */
+	DMU_OT_ZVOL_PROP,		/* ZAP */
+	/* other; for testing only! */
+	DMU_OT_PLAIN_OTHER,		/* UINT8 */
+	DMU_OT_UINT64_OTHER,		/* UINT64 */
+	DMU_OT_ZAP_OTHER,		/* ZAP */
+	/* new object types: */
+	DMU_OT_ERROR_LOG,		/* ZAP */
+	DMU_OT_SPA_HISTORY,		/* UINT8 */
+	DMU_OT_SPA_HISTORY_OFFSETS,	/* spa_his_phys_t */
+	DMU_OT_POOL_PROPS,		/* ZAP */
+	DMU_OT_DSL_PERMS,		/* ZAP */
+	DMU_OT_ACL,			/* ACL */
+	DMU_OT_SYSACL,			/* SYSACL */
+	DMU_OT_FUID,			/* FUID table (Packed NVLIST UINT8) */
+	DMU_OT_FUID_SIZE,		/* FUID table size UINT64 */
+	DMU_OT_NEXT_CLONES,		/* ZAP */
+	DMU_OT_SCAN_QUEUE,		/* ZAP */
+	DMU_OT_USERGROUP_USED,		/* ZAP */
+	DMU_OT_USERGROUP_QUOTA,		/* ZAP */
+	DMU_OT_USERREFS,		/* ZAP */
+	DMU_OT_DDT_ZAP,			/* ZAP */
+	DMU_OT_DDT_STATS,		/* ZAP */
+	DMU_OT_SA,			/* System attr */
+	DMU_OT_SA_MASTER_NODE,		/* ZAP */
+	DMU_OT_SA_ATTR_REGISTRATION,	/* ZAP */
+	DMU_OT_SA_ATTR_LAYOUTS,		/* ZAP */
+	DMU_OT_SCAN_XLATE,		/* ZAP */
+	DMU_OT_DEDUP,			/* fake dedup BP from ddt_bp_create() */
+	DMU_OT_DEADLIST,		/* ZAP */
+	DMU_OT_DEADLIST_HDR,		/* UINT64 */
+	DMU_OT_DSL_CLONES,		/* ZAP */
+	DMU_OT_BPOBJ_SUBOBJ,		/* UINT64 */
+	DMU_OT_NUMTYPES
+} dmu_object_type_t;
+
+typedef enum dmu_objset_type {
+	DMU_OST_NONE,
+	DMU_OST_META,
+	DMU_OST_ZFS,
+	DMU_OST_ZVOL,
+	DMU_OST_OTHER,			/* For testing only! */
+	DMU_OST_ANY,			/* Be careful! */
+	DMU_OST_NUMTYPES
+} dmu_objset_type_t;
+
+void byteswap_uint64_array(void *buf, size_t size);
+void byteswap_uint32_array(void *buf, size_t size);
+void byteswap_uint16_array(void *buf, size_t size);
+void byteswap_uint8_array(void *buf, size_t size);
+void zap_byteswap(void *buf, size_t size);
+void zfs_oldacl_byteswap(void *buf, size_t size);
+void zfs_acl_byteswap(void *buf, size_t size);
+void zfs_znode_byteswap(void *buf, size_t size);
+
+#define	DS_FIND_SNAPSHOTS	(1<<0)
+#define	DS_FIND_CHILDREN	(1<<1)
+
+/*
+ * The maximum number of bytes that can be accessed as part of one
+ * operation, including metadata.
+ */
+#define	DMU_MAX_ACCESS (10<<20) /* 10MB */
+#define	DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */
+
+#define	DMU_USERUSED_OBJECT	(-1ULL)
+#define	DMU_GROUPUSED_OBJECT	(-2ULL)
+#define	DMU_DEADLIST_OBJECT	(-3ULL)
+
+/*
+ * artificial blkids for bonus buffer and spill blocks
+ */
+#define	DMU_BONUS_BLKID		(-1ULL)
+#define	DMU_SPILL_BLKID		(-2ULL)
+/*
+ * Public routines to create, destroy, open, and close objsets.
+ */
+int dmu_objset_hold(const char *name, void *tag, objset_t **osp);
+int dmu_objset_own(const char *name, dmu_objset_type_t type,
+    boolean_t readonly, void *tag, objset_t **osp);
+void dmu_objset_rele(objset_t *os, void *tag);
+void dmu_objset_disown(objset_t *os, void *tag);
+int dmu_objset_open_ds(struct dsl_dataset *ds, objset_t **osp);
+
+int dmu_objset_evict_dbufs(objset_t *os);
+int dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
+    void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg);
+int dmu_objset_clone(const char *name, struct dsl_dataset *clone_origin,
+    uint64_t flags);
+int dmu_objset_destroy(const char *name, boolean_t defer);
+int dmu_snapshots_destroy(char *fsname, char *snapname, boolean_t defer);
+int dmu_objset_snapshot(char *fsname, char *snapname, char *tag,
+    struct nvlist *props, boolean_t recursive, boolean_t temporary, int fd);
+int dmu_objset_rename(const char *name, const char *newname,
+    boolean_t recursive);
+int dmu_objset_find(char *name, int func(const char *, void *), void *arg,
+    int flags);
+void dmu_objset_byteswap(void *buf, size_t size);
+
+typedef struct dmu_buf {
+	uint64_t db_object;		/* object that this buffer is part of */
+	uint64_t db_offset;		/* byte offset in this object */
+	uint64_t db_size;		/* size of buffer in bytes */
+	void *db_data;			/* data in buffer */
+} dmu_buf_t;
+
+typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr);
+
+/*
+ * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
+ */
+#define	DMU_POOL_DIRECTORY_OBJECT	1
+#define	DMU_POOL_CONFIG			"config"
+#define	DMU_POOL_ROOT_DATASET		"root_dataset"
+#define	DMU_POOL_SYNC_BPOBJ		"sync_bplist"
+#define	DMU_POOL_ERRLOG_SCRUB		"errlog_scrub"
+#define	DMU_POOL_ERRLOG_LAST		"errlog_last"
+#define	DMU_POOL_SPARES			"spares"
+#define	DMU_POOL_DEFLATE		"deflate"
+#define	DMU_POOL_HISTORY		"history"
+#define	DMU_POOL_PROPS			"pool_props"
+#define	DMU_POOL_L2CACHE		"l2cache"
+#define	DMU_POOL_TMP_USERREFS		"tmp_userrefs"
+#define	DMU_POOL_DDT			"DDT-%s-%s-%s"
+#define	DMU_POOL_DDT_STATS		"DDT-statistics"
+#define	DMU_POOL_CREATION_VERSION	"creation_version"
+#define	DMU_POOL_SCAN			"scan"
+#define	DMU_POOL_FREE_BPOBJ		"free_bpobj"
+
+/*
+ * Allocate an object from this objset.  The range of object numbers
+ * available is (0, DN_MAX_OBJECT).  Object 0 is the meta-dnode.
+ *
+ * The transaction must be assigned to a txg.  The newly allocated
+ * object will be "held" in the transaction (ie. you can modify the
+ * newly allocated object in this transaction).
+ *
+ * dmu_object_alloc() chooses an object and returns it in *objectp.
+ *
+ * dmu_object_claim() allocates a specific object number.  If that
+ * number is already allocated, it fails and returns EEXIST.
+ *
+ * Return 0 on success, or ENOSPC or EEXIST as specified above.
+ */
+uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot,
+    int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
+int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
+    int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
+int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
+    int blocksize, dmu_object_type_t bonustype, int bonuslen);
+
+/*
+ * Free an object from this objset.
+ *
+ * The object's data will be freed as well (ie. you don't need to call
+ * dmu_free(object, 0, -1, tx)).
+ *
+ * The object need not be held in the transaction.
+ *
+ * If there are any holds on this object's buffers (via dmu_buf_hold()),
+ * or tx holds on the object (via dmu_tx_hold_object()), you can not
+ * free it; it fails and returns EBUSY.
+ *
+ * If the object is not allocated, it fails and returns ENOENT.
+ *
+ * Return 0 on success, or EBUSY or ENOENT as specified above.
+ */
+int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx);
+
+/*
+ * Find the next allocated or free object.
+ *
+ * The objectp parameter is in-out.  It will be updated to be the next
+ * object which is allocated.  Ignore objects which have not been
+ * modified since txg.
+ *
+ * XXX Can only be called on a objset with no dirty data.
+ *
+ * Returns 0 on success, or ENOENT if there are no more objects.
+ */
+int dmu_object_next(objset_t *os, uint64_t *objectp,
+    boolean_t hole, uint64_t txg);
+
+/*
+ * Set the data blocksize for an object.
+ *
+ * The object cannot have any blocks allcated beyond the first.  If
+ * the first block is allocated already, the new size must be greater
+ * than the current block size.  If these conditions are not met,
+ * ENOTSUP will be returned.
+ *
+ * Returns 0 on success, or EBUSY if there are any holds on the object
+ * contents, or ENOTSUP as described above.
+ */
+int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size,
+    int ibs, dmu_tx_t *tx);
+
+/*
+ * Set the checksum property on a dnode.  The new checksum algorithm will
+ * apply to all newly written blocks; existing blocks will not be affected.
+ */
+void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
+    dmu_tx_t *tx);
+
+/*
+ * Set the compress property on a dnode.  The new compression algorithm will
+ * apply to all newly written blocks; existing blocks will not be affected.
+ */
+void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
+    dmu_tx_t *tx);
+
+/*
+ * Decide how to write a block: checksum, compression, number of copies, etc.
+ */
+#define	WP_NOFILL	0x1
+#define	WP_DMU_SYNC	0x2
+#define	WP_SPILL	0x4
+
+void dmu_write_policy(objset_t *os, struct dnode *dn, int level, int wp,
+    struct zio_prop *zp);
+/*
+ * The bonus data is accessed more or less like a regular buffer.
+ * You must dmu_bonus_hold() to get the buffer, which will give you a
+ * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus
+ * data.  As with any normal buffer, you must call dmu_buf_read() to
+ * read db_data, dmu_buf_will_dirty() before modifying it, and the
+ * object must be held in an assigned transaction before calling
+ * dmu_buf_will_dirty.  You may use dmu_buf_set_user() on the bonus
+ * buffer as well.  You must release your hold with dmu_buf_rele().
+ */
+int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **);
+int dmu_bonus_max(void);
+int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *);
+int dmu_set_bonustype(dmu_buf_t *, dmu_object_type_t, dmu_tx_t *);
+dmu_object_type_t dmu_get_bonustype(dmu_buf_t *);
+int dmu_rm_spill(objset_t *, uint64_t, dmu_tx_t *);
+
+/*
+ * Special spill buffer support used by "SA" framework
+ */
+
+int dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);
+int dmu_spill_hold_by_dnode(struct dnode *dn, uint32_t flags,
+    void *tag, dmu_buf_t **dbp);
+int dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp);
+
+/*
+ * Obtain the DMU buffer from the specified object which contains the
+ * specified offset.  dmu_buf_hold() puts a "hold" on the buffer, so
+ * that it will remain in memory.  You must release the hold with
+ * dmu_buf_rele().  You musn't access the dmu_buf_t after releasing your
+ * hold.  You must have a hold on any dmu_buf_t* you pass to the DMU.
+ *
+ * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill
+ * on the returned buffer before reading or writing the buffer's
+ * db_data.  The comments for those routines describe what particular
+ * operations are valid after calling them.
+ *
+ * The object number must be a valid, allocated object number.
+ */
+int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
+    void *tag, dmu_buf_t **, int flags);
+void dmu_buf_add_ref(dmu_buf_t *db, void* tag);
+void dmu_buf_rele(dmu_buf_t *db, void *tag);
+uint64_t dmu_buf_refcount(dmu_buf_t *db);
+
+/*
+ * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a
+ * range of an object.  A pointer to an array of dmu_buf_t*'s is
+ * returned (in *dbpp).
+ *
+ * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and
+ * frees the array.  The hold on the array of buffers MUST be released
+ * with dmu_buf_rele_array.  You can NOT release the hold on each buffer
+ * individually with dmu_buf_rele.
+ */
+int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
+    uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp);
+void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag);
+
+/*
+ * Returns NULL on success, or the existing user ptr if it's already
+ * been set.
+ *
+ * user_ptr is for use by the user and can be obtained via dmu_buf_get_user().
+ *
+ * user_data_ptr_ptr should be NULL, or a pointer to a pointer which
+ * will be set to db->db_data when you are allowed to access it.  Note
+ * that db->db_data (the pointer) can change when you do dmu_buf_read(),
+ * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill().
+ * *user_data_ptr_ptr will be set to the new value when it changes.
+ *
+ * If non-NULL, pageout func will be called when this buffer is being
+ * excised from the cache, so that you can clean up the data structure
+ * pointed to by user_ptr.
+ *
+ * dmu_evict_user() will call the pageout func for all buffers in a
+ * objset with a given pageout func.
+ */
+void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr,
+    dmu_buf_evict_func_t *pageout_func);
+/*
+ * set_user_ie is the same as set_user, but request immediate eviction
+ * when hold count goes to zero.
+ */
+void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr,
+    void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func);
+void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr,
+    void *user_ptr, void *user_data_ptr_ptr,
+    dmu_buf_evict_func_t *pageout_func);
+void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func);
+
+/*
+ * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set.
+ */
+void *dmu_buf_get_user(dmu_buf_t *db);
+
+/*
+ * Indicate that you are going to modify the buffer's data (db_data).
+ *
+ * The transaction (tx) must be assigned to a txg (ie. you've called
+ * dmu_tx_assign()).  The buffer's object must be held in the tx
+ * (ie. you've called dmu_tx_hold_object(tx, db->db_object)).
+ */
+void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx);
+
+/*
+ * Tells if the given dbuf is freeable.
+ */
+boolean_t dmu_buf_freeable(dmu_buf_t *);
+
+/*
+ * You must create a transaction, then hold the objects which you will
+ * (or might) modify as part of this transaction.  Then you must assign
+ * the transaction to a transaction group.  Once the transaction has
+ * been assigned, you can modify buffers which belong to held objects as
+ * part of this transaction.  You can't modify buffers before the
+ * transaction has been assigned; you can't modify buffers which don't
+ * belong to objects which this transaction holds; you can't hold
+ * objects once the transaction has been assigned.  You may hold an
+ * object which you are going to free (with dmu_object_free()), but you
+ * don't have to.
+ *
+ * You can abort the transaction before it has been assigned.
+ *
+ * Note that you may hold buffers (with dmu_buf_hold) at any time,
+ * regardless of transaction state.
+ */
+
+#define	DMU_NEW_OBJECT	(-1ULL)
+#define	DMU_OBJECT_END	(-1ULL)
+
+dmu_tx_t *dmu_tx_create(objset_t *os);
+void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
+void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
+    uint64_t len);
+void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, const char *name);
+void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object);
+void dmu_tx_hold_spill(dmu_tx_t *tx, uint64_t object);
+void dmu_tx_hold_sa(dmu_tx_t *tx, struct sa_handle *hdl, boolean_t may_grow);
+void dmu_tx_hold_sa_create(dmu_tx_t *tx, int total_size);
+void dmu_tx_abort(dmu_tx_t *tx);
+int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
+void dmu_tx_wait(dmu_tx_t *tx);
+void dmu_tx_commit(dmu_tx_t *tx);
+
+/*
+ * To register a commit callback, dmu_tx_callback_register() must be called.
+ *
+ * dcb_data is a pointer to caller private data that is passed on as a
+ * callback parameter. The caller is responsible for properly allocating and
+ * freeing it.
+ *
+ * When registering a callback, the transaction must be already created, but
+ * it cannot be committed or aborted. It can be assigned to a txg or not.
+ *
+ * The callback will be called after the transaction has been safely written
+ * to stable storage and will also be called if the dmu_tx is aborted.
+ * If there is any error which prevents the transaction from being committed to
+ * disk, the callback will be called with a value of error != 0.
+ */
+typedef void dmu_tx_callback_func_t(void *dcb_data, int error);
+
+void dmu_tx_callback_register(dmu_tx_t *tx, dmu_tx_callback_func_t *dcb_func,
+    void *dcb_data);
+
+/*
+ * Free up the data blocks for a defined range of a file.  If size is
+ * zero, the range from offset to end-of-file is freed.
+ */
+int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
+	uint64_t size, dmu_tx_t *tx);
+int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset,
+	uint64_t size);
+int dmu_free_object(objset_t *os, uint64_t object);
+
+/*
+ * Convenience functions.
+ *
+ * Canfail routines will return 0 on success, or an errno if there is a
+ * nonrecoverable I/O error.
+ */
+#define	DMU_READ_PREFETCH	0 /* prefetch */
+#define	DMU_READ_NO_PREFETCH	1 /* don't prefetch */
+int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+	void *buf, uint32_t flags);
+void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+	const void *buf, dmu_tx_t *tx);
+void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+	dmu_tx_t *tx);
+#ifdef _KERNEL
+int dmu_read_req(objset_t *os, uint64_t object, struct request *req);
+int dmu_write_req(objset_t *os, uint64_t object, struct request *req, dmu_tx_t *tx);
+#endif
+#ifdef HAVE_ZPL
+int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset,
+    uint64_t size, struct page *pp, dmu_tx_t *tx);
+#endif
+struct arc_buf *dmu_request_arcbuf(dmu_buf_t *handle, int size);
+void dmu_return_arcbuf(struct arc_buf *buf);
+void dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, struct arc_buf *buf,
+    dmu_tx_t *tx);
+int dmu_xuio_init(struct xuio *uio, int niov);
+void dmu_xuio_fini(struct xuio *uio);
+int dmu_xuio_add(struct xuio *uio, struct arc_buf *abuf, offset_t off,
+    size_t n);
+int dmu_xuio_cnt(struct xuio *uio);
+struct arc_buf *dmu_xuio_arcbuf(struct xuio *uio, int i);
+void dmu_xuio_clear(struct xuio *uio, int i);
+void xuio_stat_wbuf_copied(void);
+void xuio_stat_wbuf_nocopy(void);
+
+extern int zfs_prefetch_disable;
+
+/*
+ * Asynchronously try to read in the data.
+ */
+void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset,
+    uint64_t len);
+
+typedef struct dmu_object_info {
+	/* All sizes are in bytes unless otherwise indicated. */
+	uint32_t doi_data_block_size;
+	uint32_t doi_metadata_block_size;
+	dmu_object_type_t doi_type;
+	dmu_object_type_t doi_bonus_type;
+	uint64_t doi_bonus_size;
+	uint8_t doi_indirection;		/* 2 = dnode->indirect->data */
+	uint8_t doi_checksum;
+	uint8_t doi_compress;
+	uint8_t doi_pad[5];
+	uint64_t doi_physical_blocks_512;	/* data + metadata, 512b blks */
+	uint64_t doi_max_offset;
+	uint64_t doi_fill_count;		/* number of non-empty blocks */
+} dmu_object_info_t;
+
+typedef void arc_byteswap_func_t(void *buf, size_t size);
+
+typedef struct dmu_object_type_info {
+	arc_byteswap_func_t	*ot_byteswap;
+	boolean_t		ot_metadata;
+	char			*ot_name;
+} dmu_object_type_info_t;
+
+extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
+
+/*
+ * Get information on a DMU object.
+ *
+ * Return 0 on success or ENOENT if object is not allocated.
+ *
+ * If doi is NULL, just indicates whether the object exists.
+ */
+int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi);
+void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi);
+void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi);
+void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize,
+    u_longlong_t *nblk512);
+
+typedef struct dmu_objset_stats {
+	uint64_t dds_num_clones; /* number of clones of this */
+	uint64_t dds_creation_txg;
+	uint64_t dds_guid;
+	dmu_objset_type_t dds_type;
+	uint8_t dds_is_snapshot;
+	uint8_t dds_inconsistent;
+	char dds_origin[MAXNAMELEN];
+} dmu_objset_stats_t;
+
+/*
+ * Get stats on a dataset.
+ */
+void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);
+
+/*
+ * Add entries to the nvlist for all the objset's properties.  See
+ * zfs_prop_table[] and zfs(1m) for details on the properties.
+ */
+void dmu_objset_stats(objset_t *os, struct nvlist *nv);
+
+/*
+ * Get the space usage statistics for statvfs().
+ *
+ * refdbytes is the amount of space "referenced" by this objset.
+ * availbytes is the amount of space available to this objset, taking
+ * into account quotas & reservations, assuming that no other objsets
+ * use the space first.  These values correspond to the 'referenced' and
+ * 'available' properties, described in the zfs(1m) manpage.
+ *
+ * usedobjs and availobjs are the number of objects currently allocated,
+ * and available.
+ */
+void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
+    uint64_t *usedobjsp, uint64_t *availobjsp);
+
+/*
+ * The fsid_guid is a 56-bit ID that can change to avoid collisions.
+ * (Contrast with the ds_guid which is a 64-bit ID that will never
+ * change, so there is a small probability that it will collide.)
+ */
+uint64_t dmu_objset_fsid_guid(objset_t *os);
+
+/*
+ * Get the [cm]time for an objset's snapshot dir
+ */
+timestruc_t dmu_objset_snap_cmtime(objset_t *os);
+
+int dmu_objset_is_snapshot(objset_t *os);
+
+extern struct spa *dmu_objset_spa(objset_t *os);
+extern struct zilog *dmu_objset_zil(objset_t *os);
+extern struct dsl_pool *dmu_objset_pool(objset_t *os);
+extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
+extern void dmu_objset_name(objset_t *os, char *buf);
+extern dmu_objset_type_t dmu_objset_type(objset_t *os);
+extern uint64_t dmu_objset_id(objset_t *os);
+extern uint64_t dmu_objset_syncprop(objset_t *os);
+extern uint64_t dmu_objset_logbias(objset_t *os);
+extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
+    uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
+extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
+    int maxlen, boolean_t *conflict);
+extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
+    uint64_t *idp, uint64_t *offp);
+
+typedef int objset_used_cb_t(dmu_object_type_t bonustype,
+    void *bonus, uint64_t *userp, uint64_t *groupp);
+extern void dmu_objset_register_type(dmu_objset_type_t ost,
+    objset_used_cb_t *cb);
+extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
+extern void *dmu_objset_get_user(objset_t *os);
+
+/*
+ * Return the txg number for the given assigned transaction.
+ */
+uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
+
+/*
+ * Synchronous write.
+ * If a parent zio is provided this function initiates a write on the
+ * provided buffer as a child of the parent zio.
+ * In the absence of a parent zio, the write is completed synchronously.
+ * At write completion, blk is filled with the bp of the written block.
+ * Note that while the data covered by this function will be on stable
+ * storage when the write completes this new data does not become a
+ * permanent part of the file until the associated transaction commits.
+ */
+
+/*
+ * {zfs,zvol,ztest}_get_done() args
+ */
+typedef struct zgd {
+	struct zilog	*zgd_zilog;
+	struct blkptr	*zgd_bp;
+	dmu_buf_t	*zgd_db;
+	struct rl	*zgd_rl;
+	void		*zgd_private;
+} zgd_t;
+
+typedef void dmu_sync_cb_t(zgd_t *arg, int error);
+int dmu_sync(struct zio *zio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd);
+
+/*
+ * Find the next hole or data block in file starting at *off
+ * Return found offset in *off. Return ESRCH for end of file.
+ */
+int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole,
+    uint64_t *off);
+
+/*
+ * Initial setup and final teardown.
+ */
+extern void dmu_init(void);
+extern void dmu_fini(void);
+
+typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
+    uint64_t object, uint64_t offset, int len);
+void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
+    dmu_traverse_cb_t cb, void *arg);
+
+int dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
+    struct vnode *vp, offset_t *off);
+
+typedef struct dmu_recv_cookie {
+	/*
+	 * This structure is opaque!
+	 *
+	 * If logical and real are different, we are recving the stream
+	 * into the "real" temporary clone, and then switching it with
+	 * the "logical" target.
+	 */
+	struct dsl_dataset *drc_logical_ds;
+	struct dsl_dataset *drc_real_ds;
+	struct drr_begin *drc_drrb;
+	char *drc_tosnap;
+	char *drc_top_ds;
+	boolean_t drc_newfs;
+	boolean_t drc_force;
+} dmu_recv_cookie_t;
+
+int dmu_recv_begin(char *tofs, char *tosnap, char *topds, struct drr_begin *,
+    boolean_t force, objset_t *origin, dmu_recv_cookie_t *);
+int dmu_recv_stream(dmu_recv_cookie_t *drc, struct vnode *vp, offset_t *voffp,
+    int cleanup_fd, uint64_t *action_handlep);
+int dmu_recv_end(dmu_recv_cookie_t *drc);
+
+int dmu_diff(objset_t *tosnap, objset_t *fromsnap, struct vnode *vp,
+    offset_t *off);
+
+/* CRC64 table */
+#define	ZFS_CRC64_POLY	0xC96C5795D7870F42ULL	/* ECMA-182, reflected form */
+extern uint64_t zfs_crc64_table[256];
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif	/* _SYS_DMU_H */