1 files changed, 334 insertions, 0 deletions
diff --git a/sys/contrib/opensolaris/uts/common/fs/zfs/sys/dbuf.h b/sys/contrib/opensolaris/uts/common/fs/zfs/sys/dbuf.h
new file mode 100644
index 0000000..d33657b
--- /dev/null
+++ b/sys/contrib/opensolaris/uts/common/fs/zfs/sys/dbuf.h
@@ -0,0 +1,334 @@
+/*
+ * 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 2007 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#ifndef	_SYS_DBUF_H
+#define	_SYS_DBUF_H
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <sys/dmu.h>
+#include <sys/spa.h>
+#include <sys/txg.h>
+#include <sys/zio.h>
+#include <sys/arc.h>
+#include <sys/zfs_context.h>
+#include <sys/refcount.h>
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+#define	DB_BONUS_BLKID (-1ULL)
+#define	IN_DMU_SYNC 2
+
+/*
+ * define flags for dbuf_read
+ */
+
+#define	DB_RF_MUST_SUCCEED	(1 << 0)
+#define	DB_RF_CANFAIL		(1 << 1)
+#define	DB_RF_HAVESTRUCT	(1 << 2)
+#define	DB_RF_NOPREFETCH	(1 << 3)
+#define	DB_RF_NEVERWAIT		(1 << 4)
+#define	DB_RF_CACHED		(1 << 5)
+
+/*
+ * The state transition diagram for dbufs looks like:
+ *
+ *		+----> READ ----+
+ *		|		|
+ *		|		V
+ *  (alloc)-->UNCACHED	     CACHED-->EVICTING-->(free)
+ *		|		^
+ *		|		|
+ *		+----> FILL ----+
+ */
+typedef enum dbuf_states {
+	DB_UNCACHED,
+	DB_FILL,
+	DB_READ,
+	DB_CACHED,
+	DB_EVICTING
+} dbuf_states_t;
+
+struct objset_impl;
+struct dnode;
+struct dmu_tx;
+
+/*
+ * level = 0 means the user data
+ * level = 1 means the single indirect block
+ * etc.
+ */
+
+#define	LIST_LINK_INACTIVE(link) \
+	((link)->list_next == NULL && (link)->list_prev == NULL)
+
+struct dmu_buf_impl;
+
+typedef enum override_states {
+	DR_NOT_OVERRIDDEN,
+	DR_IN_DMU_SYNC,
+	DR_OVERRIDDEN
+} override_states_t;
+
+typedef struct dbuf_dirty_record {
+	/* link on our parents dirty list */
+	list_node_t dr_dirty_node;
+
+	/* transaction group this data will sync in */
+	uint64_t dr_txg;
+
+	/* zio of outstanding write IO */
+	zio_t *dr_zio;
+
+	/* pointer back to our dbuf */
+	struct dmu_buf_impl *dr_dbuf;
+
+	/* pointer to next dirty record */
+	struct dbuf_dirty_record *dr_next;
+
+	/* pointer to parent dirty record */
+	struct dbuf_dirty_record *dr_parent;
+
+	union dirty_types {
+		struct dirty_indirect {
+
+			/* protect access to list */
+			kmutex_t dr_mtx;
+
+			/* Our list of dirty children */
+			list_t dr_children;
+		} di;
+		struct dirty_leaf {
+
+			/*
+			 * dr_data is set when we dirty the buffer
+			 * so that we can retain the pointer even if it
+			 * gets COW'd in a subsequent transaction group.
+			 */
+			arc_buf_t *dr_data;
+			blkptr_t dr_overridden_by;
+			override_states_t dr_override_state;
+		} dl;
+	} dt;
+} dbuf_dirty_record_t;
+
+typedef struct dmu_buf_impl {
+	/*
+	 * The following members are immutable, with the exception of
+	 * db.db_data, which is protected by db_mtx.
+	 */
+
+	/* the publicly visible structure */
+	dmu_buf_t db;
+
+	/* the objset we belong to */
+	struct objset_impl *db_objset;
+
+	/*
+	 * the dnode we belong to (NULL when evicted)
+	 */
+	struct dnode *db_dnode;
+
+	/*
+	 * our parent buffer; if the dnode points to us directly,
+	 * db_parent == db_dnode->dn_dbuf
+	 * only accessed by sync thread ???
+	 * (NULL when evicted)
+	 */
+	struct dmu_buf_impl *db_parent;
+
+	/*
+	 * link for hash table of all dmu_buf_impl_t's
+	 */
+	struct dmu_buf_impl *db_hash_next;
+
+	/* our block number */
+	uint64_t db_blkid;
+
+	/*
+	 * Pointer to the blkptr_t which points to us. May be NULL if we
+	 * don't have one yet. (NULL when evicted)
+	 */
+	blkptr_t *db_blkptr;
+
+	/*
+	 * Our indirection level.  Data buffers have db_level==0.
+	 * Indirect buffers which point to data buffers have
+	 * db_level==1. etc.  Buffers which contain dnodes have
+	 * db_level==0, since the dnodes are stored in a file.
+	 */
+	uint8_t db_level;
+
+	/* db_mtx protects the members below */
+	kmutex_t db_mtx;
+
+	/*
+	 * Current state of the buffer
+	 */
+	dbuf_states_t db_state;
+
+	/*
+	 * Refcount accessed by dmu_buf_{hold,rele}.
+	 * If nonzero, the buffer can't be destroyed.
+	 * Protected by db_mtx.
+	 */
+	refcount_t db_holds;
+
+	/* buffer holding our data */
+	arc_buf_t *db_buf;
+
+	kcondvar_t db_changed;
+	dbuf_dirty_record_t *db_data_pending;
+
+	/* pointer to most recent dirty record for this buffer */
+	dbuf_dirty_record_t *db_last_dirty;
+
+	/*
+	 * Our link on the owner dnodes's dn_dbufs list.
+	 * Protected by its dn_dbufs_mtx.
+	 */
+	list_node_t db_link;
+
+	/* Data which is unique to data (leaf) blocks: */
+
+	/* stuff we store for the user (see dmu_buf_set_user) */
+	void *db_user_ptr;
+	void **db_user_data_ptr_ptr;
+	dmu_buf_evict_func_t *db_evict_func;
+
+	uint8_t db_immediate_evict;
+	uint8_t db_freed_in_flight;
+
+	uint8_t db_dirtycnt;
+} dmu_buf_impl_t;
+
+/* Note: the dbuf hash table is exposed only for the mdb module */
+#define	DBUF_MUTEXES 256
+#define	DBUF_HASH_MUTEX(h, idx) (&(h)->hash_mutexes[(idx) & (DBUF_MUTEXES-1)])
+typedef struct dbuf_hash_table {
+	uint64_t hash_table_mask;
+	dmu_buf_impl_t **hash_table;
+	kmutex_t hash_mutexes[DBUF_MUTEXES];
+} dbuf_hash_table_t;
+
+
+uint64_t dbuf_whichblock(struct dnode *di, uint64_t offset);
+
+dmu_buf_impl_t *dbuf_create_tlib(struct dnode *dn, char *data);
+dmu_buf_impl_t *dbuf_create_bonus(struct dnode *dn);
+
+dmu_buf_impl_t *dbuf_hold(struct dnode *dn, uint64_t blkid, void *tag);
+dmu_buf_impl_t *dbuf_hold_level(struct dnode *dn, int level, uint64_t blkid,
+    void *tag);
+int dbuf_hold_impl(struct dnode *dn, uint8_t level, uint64_t blkid, int create,
+    void *tag, dmu_buf_impl_t **dbp);
+
+void dbuf_prefetch(struct dnode *dn, uint64_t blkid);
+
+void dbuf_add_ref(dmu_buf_impl_t *db, void *tag);
+uint64_t dbuf_refcount(dmu_buf_impl_t *db);
+
+void dbuf_rele(dmu_buf_impl_t *db, void *tag);
+
+dmu_buf_impl_t *dbuf_find(struct dnode *dn, uint8_t level, uint64_t blkid);
+
+int dbuf_read(dmu_buf_impl_t *db, zio_t *zio, uint32_t flags);
+void dbuf_will_dirty(dmu_buf_impl_t *db, dmu_tx_t *tx);
+void dmu_buf_will_fill(dmu_buf_t *db, dmu_tx_t *tx);
+void dbuf_fill_done(dmu_buf_impl_t *db, dmu_tx_t *tx);
+void dmu_buf_will_fill(dmu_buf_t *db, dmu_tx_t *tx);
+void dmu_buf_fill_done(dmu_buf_t *db, dmu_tx_t *tx);
+dbuf_dirty_record_t *dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t *tx);
+
+void dbuf_clear(dmu_buf_impl_t *db);
+void dbuf_evict(dmu_buf_impl_t *db);
+
+void dbuf_setdirty(dmu_buf_impl_t *db, dmu_tx_t *tx);
+void dbuf_unoverride(dbuf_dirty_record_t *dr);
+void dbuf_sync_list(list_t *list, dmu_tx_t *tx);
+
+void dbuf_free_range(struct dnode *dn, uint64_t blkid, uint64_t nblks,
+    struct dmu_tx *);
+
+void dbuf_new_size(dmu_buf_impl_t *db, int size, dmu_tx_t *tx);
+
+void dbuf_init(void);
+void dbuf_fini(void);
+
+#define	DBUF_GET_BUFC_TYPE(db)					\
+	((((db)->db_level > 0) ||				\
+	    (dmu_ot[(db)->db_dnode->dn_type].ot_metadata)) ?	\
+	    ARC_BUFC_METADATA : ARC_BUFC_DATA);
+
+#ifdef ZFS_DEBUG
+
+/*
+ * There should be a ## between the string literal and fmt, to make it
+ * clear that we're joining two strings together, but gcc does not
+ * support that preprocessor token.
+ */
+#define	dprintf_dbuf(dbuf, fmt, ...) do { \
+	if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
+	char __db_buf[32]; \
+	uint64_t __db_obj = (dbuf)->db.db_object; \
+	if (__db_obj == DMU_META_DNODE_OBJECT) \
+		(void) strcpy(__db_buf, "mdn"); \
+	else \
+		(void) snprintf(__db_buf, sizeof (__db_buf), "%lld", \
+		    (u_longlong_t)__db_obj); \
+	dprintf_ds((dbuf)->db_objset->os_dsl_dataset, \
+	    "obj=%s lvl=%u blkid=%lld " fmt, \
+	    __db_buf, (dbuf)->db_level, \
+	    (u_longlong_t)(dbuf)->db_blkid, __VA_ARGS__); \
+	} \
+_NOTE(CONSTCOND) } while (0)
+
+#define	dprintf_dbuf_bp(db, bp, fmt, ...) do {			\
+	if (zfs_flags & ZFS_DEBUG_DPRINTF) {			\
+	char *__blkbuf = kmem_alloc(BP_SPRINTF_LEN, KM_SLEEP);	\
+	sprintf_blkptr(__blkbuf, BP_SPRINTF_LEN, bp);		\
+	dprintf_dbuf(db, fmt " %s\n", __VA_ARGS__, __blkbuf);	\
+	kmem_free(__blkbuf, BP_SPRINTF_LEN);			\
+	} 							\
+_NOTE(CONSTCOND) } while (0)
+
+#define	DBUF_VERIFY(db)	dbuf_verify(db)
+
+#else
+
+#define	dprintf_dbuf(db, fmt, ...)
+#define	dprintf_dbuf_bp(db, bp, fmt, ...)
+#define	DBUF_VERIFY(db)
+
+#endif
+
+
+#ifdef	__cplusplus
+}
+#endif
+
+#endif /* _SYS_DBUF_H */