aboutsummaryrefslogtreecommitdiffstats
path: root/uts/common/fs/zfs/sys/dbuf.h
diff options
context:
space:
mode:
Diffstat (limited to 'uts/common/fs/zfs/sys/dbuf.h')
-rw-r--r--uts/common/fs/zfs/sys/dbuf.h375
1 files changed, 375 insertions, 0 deletions
diff --git a/uts/common/fs/zfs/sys/dbuf.h b/uts/common/fs/zfs/sys/dbuf.h
new file mode 100644
index 000000000000..cf1bbc030f45
--- /dev/null
+++ b/uts/common/fs/zfs/sys/dbuf.h
@@ -0,0 +1,375 @@
+/*
+ * 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.
+ */
+
+#ifndef _SYS_DBUF_H
+#define _SYS_DBUF_H
+
+#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>
+#include <sys/zrlock.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#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 simplified state transition diagram for dbufs looks like:
+ *
+ * +----> READ ----+
+ * | |
+ * | V
+ * (alloc)-->UNCACHED CACHED-->EVICTING-->(free)
+ * | ^ ^
+ * | | |
+ * +----> FILL ----+ |
+ * | |
+ * | |
+ * +--------> NOFILL -------+
+ */
+typedef enum dbuf_states {
+ DB_UNCACHED,
+ DB_FILL,
+ DB_NOFILL,
+ DB_READ,
+ DB_CACHED,
+ DB_EVICTING
+} dbuf_states_t;
+
+struct dnode;
+struct dmu_tx;
+
+/*
+ * level = 0 means the user data
+ * level = 1 means the single indirect block
+ * etc.
+ */
+
+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;
+ uint8_t dr_copies;
+ } 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 *db_objset;
+
+ /*
+ * handle to safely access the dnode we belong to (NULL when evicted)
+ */
+ struct dnode_handle *db_dnode_handle;
+
+ /*
+ * our parent buffer; if the dnode points to us directly,
+ * db_parent == db_dnode_handle->dnh_dnode->dn_dbuf
+ * only accessed by sync thread ???
+ * (NULL when evicted)
+ * May change from NULL to non-NULL under the protection of db_mtx
+ * (see dbuf_check_blkptr())
+ */
+ 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);
+void dbuf_create_bonus(struct dnode *dn);
+int dbuf_spill_set_blksz(dmu_buf_t *db, uint64_t blksz, dmu_tx_t *tx);
+void dbuf_spill_hold(struct dnode *dn, dmu_buf_impl_t **dbp, void *tag);
+
+void dbuf_rm_spill(struct dnode *dn, dmu_tx_t *tx);
+
+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);
+void dbuf_rele_and_unlock(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 dbuf_fill_done(dmu_buf_impl_t *db, dmu_tx_t *tx);
+void dmu_buf_will_not_fill(dmu_buf_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);
+void dbuf_assign_arcbuf(dmu_buf_impl_t *db, arc_buf_t *buf, dmu_tx_t *tx);
+dbuf_dirty_record_t *dbuf_dirty(dmu_buf_impl_t *db, dmu_tx_t *tx);
+arc_buf_t *dbuf_loan_arcbuf(dmu_buf_impl_t *db);
+
+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_release_bp(dmu_buf_impl_t *db);
+
+void dbuf_free_range(struct dnode *dn, uint64_t start, uint64_t end,
+ struct dmu_tx *);
+
+void dbuf_new_size(dmu_buf_impl_t *db, int size, dmu_tx_t *tx);
+
+#define DB_DNODE(_db) ((_db)->db_dnode_handle->dnh_dnode)
+#define DB_DNODE_LOCK(_db) ((_db)->db_dnode_handle->dnh_zrlock)
+#define DB_DNODE_ENTER(_db) (zrl_add(&DB_DNODE_LOCK(_db)))
+#define DB_DNODE_EXIT(_db) (zrl_remove(&DB_DNODE_LOCK(_db)))
+#define DB_DNODE_HELD(_db) (!zrl_is_zero(&DB_DNODE_LOCK(_db)))
+#define DB_GET_SPA(_spa_p, _db) { \
+ dnode_t *__dn; \
+ DB_DNODE_ENTER(_db); \
+ __dn = DB_DNODE(_db); \
+ *(_spa_p) = __dn->dn_objset->os_spa; \
+ DB_DNODE_EXIT(_db); \
+}
+#define DB_GET_OBJSET(_os_p, _db) { \
+ dnode_t *__dn; \
+ DB_DNODE_ENTER(_db); \
+ __dn = DB_DNODE(_db); \
+ *(_os_p) = __dn->dn_objset; \
+ DB_DNODE_EXIT(_db); \
+}
+
+void dbuf_init(void);
+void dbuf_fini(void);
+
+boolean_t dbuf_is_metadata(dmu_buf_impl_t *db);
+
+#define DBUF_IS_METADATA(_db) \
+ (dbuf_is_metadata(_db))
+
+#define DBUF_GET_BUFC_TYPE(_db) \
+ (DBUF_IS_METADATA(_db) ? ARC_BUFC_METADATA : ARC_BUFC_DATA)
+
+#define DBUF_IS_CACHEABLE(_db) \
+ ((_db)->db_objset->os_primary_cache == ZFS_CACHE_ALL || \
+ (DBUF_IS_METADATA(_db) && \
+ ((_db)->db_objset->os_primary_cache == ZFS_CACHE_METADATA)))
+
+#define DBUF_IS_L2CACHEABLE(_db) \
+ ((_db)->db_objset->os_secondary_cache == ZFS_CACHE_ALL || \
+ (DBUF_IS_METADATA(_db) && \
+ ((_db)->db_objset->os_secondary_cache == ZFS_CACHE_METADATA)))
+
+#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); \
+ 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 */