dmu_buf_impl Struct Reference

#include <dbuf.h>

Collaboration diagram for dmu_buf_impl:

Data Fields
dmu_buf_t	db
	the publicly visible structure
struct objset *	db_objset
	the objset we belong to
struct dnode_handle *	db_dnode_handle
	handle to safely access the dnode we belong to (NULL when evicted)
struct dmu_buf_impl *	db_parent
	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_hash_next
	link for hash table of all dmu_buf_impl_t's
uint64_t	db_blkid
	our block number
blkptr_t *	db_blkptr
	Pointer to the blkptr_t which points to us.
uint8_t	db_level
	Our indirection level.
kmutex_t	db_mtx
	db_mtx protects the members below
dbuf_states_t	db_state
	Current state of the buffer.
refcount_t	db_holds
	Refcount accessed by dmu_buf_{hold,rele}.
arc_buf_t *	db_buf
	buffer holding our data
kcondvar_t	db_changed
dbuf_dirty_record_t *	db_data_pending
dbuf_dirty_record_t *	db_last_dirty
	pointer to most recent dirty record for this buffer
list_node_t	db_link
	Our link on the owner dnodes's dn_dbufs list.
void *	db_user_ptr
	Data which is unique to data (leaf) blocks:
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

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Detailed Description

Definition at line 149 of file dbuf.h.

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Field Documentation

dmu_buf_t dmu_buf_impl::db

the publicly visible structure

Definition at line 156 of file dbuf.h.

uint64_t dmu_buf_impl::db_blkid

our block number

Definition at line 182 of file dbuf.h.

blkptr_t* dmu_buf_impl::db_blkptr

Pointer to the blkptr_t which points to us.

May be NULL if we don't have one yet. (NULL when evicted)

Definition at line 188 of file dbuf.h.

arc_buf_t* dmu_buf_impl::db_buf

buffer holding our data

Definition at line 214 of file dbuf.h.

kcondvar_t dmu_buf_impl::db_changed

Definition at line 216 of file dbuf.h.

dbuf_dirty_record_t* dmu_buf_impl::db_data_pending

Definition at line 217 of file dbuf.h.

uint8_t dmu_buf_impl::db_dirtycnt

Definition at line 238 of file dbuf.h.

struct dnode_handle* dmu_buf_impl::db_dnode_handle

handle to safely access the dnode we belong to (NULL when evicted)

Definition at line 164 of file dbuf.h.

dmu_buf_evict_func_t* dmu_buf_impl::db_evict_func

Definition at line 233 of file dbuf.h.

uint8_t dmu_buf_impl::db_freed_in_flight

Definition at line 236 of file dbuf.h.

struct dmu_buf_impl* dmu_buf_impl::db_hash_next

link for hash table of all dmu_buf_impl_t's

Definition at line 179 of file dbuf.h.

refcount_t dmu_buf_impl::db_holds

Refcount accessed by dmu_buf_{hold,rele}.

If nonzero, the buffer can't be destroyed. Protected by db_mtx.

Definition at line 211 of file dbuf.h.

uint8_t dmu_buf_impl::db_immediate_evict

Definition at line 235 of file dbuf.h.

dbuf_dirty_record_t* dmu_buf_impl::db_last_dirty

pointer to most recent dirty record for this buffer

Definition at line 220 of file dbuf.h.

uint8_t dmu_buf_impl::db_level

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.

Definition at line 196 of file dbuf.h.

list_node_t dmu_buf_impl::db_link

Our link on the owner dnodes's dn_dbufs list.

Protected by its dn_dbufs_mtx.

Definition at line 226 of file dbuf.h.

kmutex_t dmu_buf_impl::db_mtx

db_mtx protects the members below

Definition at line 199 of file dbuf.h.

struct objset* dmu_buf_impl::db_objset

the objset we belong to

Definition at line 159 of file dbuf.h.

struct dmu_buf_impl* dmu_buf_impl::db_parent

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())

Definition at line 174 of file dbuf.h.

dbuf_states_t dmu_buf_impl::db_state

Current state of the buffer.

Definition at line 204 of file dbuf.h.

void** dmu_buf_impl::db_user_data_ptr_ptr

Definition at line 232 of file dbuf.h.

void* dmu_buf_impl::db_user_ptr

Data which is unique to data (leaf) blocks:

stuff we store for the user (see dmu_buf_set_user)

Definition at line 231 of file dbuf.h.

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The documentation for this struct was generated from the following file:

• sys/dbuf.h