mirror_zfs/include/sys/sa.h
Justin T. Gibbs 0c66c32d1d Illumos 5056 - ZFS deadlock on db_mtx and dn_holds
5056 ZFS deadlock on db_mtx and dn_holds
Author: Justin Gibbs <justing@spectralogic.com>
Reviewed by: Will Andrews <willa@spectralogic.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/5056
  https://github.com/illumos/illumos-gate/commit/bc9014e

Porting Notes:

sa_handle_get_from_db():
  - the original patch includes an otherwise unmentioned fix for a
    possible usage of an uninitialised variable

dmu_objset_open_impl():
  - Under Illumos list_link_init() is the same as filling a list_node_t
    with NULLs, so they don't notice if they miss doing list_link_init()
    on a zero'd containing structure (e.g. allocated with kmem_zalloc as
    here). Under Linux, not so much: an uninitialised list_node_t goes
    "Boom!" some time later when it's used or destroyed.

dmu_objset_evict_dbufs():
  - reduce stack usage using kmem_alloc()

Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2015-04-28 16:25:34 -07:00

171 lines
5.1 KiB
C

/*
* 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) 2010, Oracle and/or its affiliates. All rights reserved.
*/
#ifndef _SYS_SA_H
#define _SYS_SA_H
#include <sys/dmu.h>
/*
* Currently available byteswap functions.
* If it all possible new attributes should used
* one of the already defined byteswap functions.
* If a new byteswap function is added then the
* ZPL/Pool version will need to be bumped.
*/
typedef enum sa_bswap_type {
SA_UINT64_ARRAY,
SA_UINT32_ARRAY,
SA_UINT16_ARRAY,
SA_UINT8_ARRAY,
SA_ACL,
} sa_bswap_type_t;
typedef uint16_t sa_attr_type_t;
/*
* Attribute to register support for.
*/
typedef struct sa_attr_reg {
char *sa_name; /* attribute name */
uint16_t sa_length;
sa_bswap_type_t sa_byteswap; /* bswap functon enum */
sa_attr_type_t sa_attr; /* filled in during registration */
} sa_attr_reg_t;
typedef void (sa_data_locator_t)(void **, uint32_t *, uint32_t,
boolean_t, void *userptr);
/*
* array of attributes to store.
*
* This array should be treated as opaque/private data.
* The SA_BULK_ADD_ATTR() macro should be used for manipulating
* the array.
*
* When sa_replace_all_by_template() is used the attributes
* will be stored in the order defined in the array, except that
* the attributes may be split between the bonus and the spill buffer
*
*/
typedef struct sa_bulk_attr {
void *sa_data;
sa_data_locator_t *sa_data_func;
uint16_t sa_length;
sa_attr_type_t sa_attr;
/* the following are private to the sa framework */
void *sa_addr;
uint16_t sa_buftype;
uint16_t sa_size;
} sa_bulk_attr_t;
/*
* special macro for adding entries for bulk attr support
* bulk - sa_bulk_attr_t
* count - integer that will be incremented during each add
* attr - attribute to manipulate
* func - function for accessing data.
* data - pointer to data.
* len - length of data
*/
#define SA_ADD_BULK_ATTR(b, idx, attr, func, data, len) \
{ \
b[idx].sa_attr = attr;\
b[idx].sa_data_func = func; \
b[idx].sa_data = data; \
b[idx++].sa_length = len; \
}
typedef struct sa_os sa_os_t;
typedef enum sa_handle_type {
SA_HDL_SHARED,
SA_HDL_PRIVATE
} sa_handle_type_t;
struct sa_handle;
typedef void *sa_lookup_tab_t;
typedef struct sa_handle sa_handle_t;
typedef void (sa_update_cb_t)(sa_handle_t *, dmu_tx_t *tx);
int sa_handle_get(objset_t *, uint64_t, void *userp,
sa_handle_type_t, sa_handle_t **);
int sa_handle_get_from_db(objset_t *, dmu_buf_t *, void *userp,
sa_handle_type_t, sa_handle_t **);
void sa_handle_destroy(sa_handle_t *);
int sa_buf_hold(objset_t *, uint64_t, void *, dmu_buf_t **);
void sa_buf_rele(dmu_buf_t *, void *);
int sa_lookup(sa_handle_t *, sa_attr_type_t, void *buf, uint32_t buflen);
int sa_update(sa_handle_t *, sa_attr_type_t, void *buf,
uint32_t buflen, dmu_tx_t *);
int sa_remove(sa_handle_t *, sa_attr_type_t, dmu_tx_t *);
int sa_bulk_lookup(sa_handle_t *, sa_bulk_attr_t *, int count);
int sa_bulk_lookup_locked(sa_handle_t *, sa_bulk_attr_t *, int count);
int sa_bulk_update(sa_handle_t *, sa_bulk_attr_t *, int count, dmu_tx_t *);
int sa_size(sa_handle_t *, sa_attr_type_t, int *);
int sa_update_from_cb(sa_handle_t *, sa_attr_type_t,
uint32_t buflen, sa_data_locator_t *, void *userdata, dmu_tx_t *);
void sa_object_info(sa_handle_t *, dmu_object_info_t *);
void sa_object_size(sa_handle_t *, uint32_t *, u_longlong_t *);
void *sa_get_userdata(sa_handle_t *);
void sa_set_userp(sa_handle_t *, void *);
dmu_buf_t *sa_get_db(sa_handle_t *);
uint64_t sa_handle_object(sa_handle_t *);
boolean_t sa_attr_would_spill(sa_handle_t *, sa_attr_type_t, int size);
void sa_spill_rele(sa_handle_t *);
void sa_register_update_callback(objset_t *, sa_update_cb_t *);
int sa_setup(objset_t *, uint64_t, sa_attr_reg_t *, int, sa_attr_type_t **);
void sa_tear_down(objset_t *);
int sa_replace_all_by_template(sa_handle_t *, sa_bulk_attr_t *,
int, dmu_tx_t *);
int sa_replace_all_by_template_locked(sa_handle_t *, sa_bulk_attr_t *,
int, dmu_tx_t *);
boolean_t sa_enabled(objset_t *);
void sa_cache_init(void);
void sa_cache_fini(void);
int sa_set_sa_object(objset_t *, uint64_t);
int sa_hdrsize(void *);
void sa_handle_lock(sa_handle_t *);
void sa_handle_unlock(sa_handle_t *);
#ifdef _KERNEL
int sa_lookup_uio(sa_handle_t *, sa_attr_type_t, uio_t *);
#endif
#ifdef __cplusplus
extern "C" {
#endif
#ifdef __cplusplus
}
#endif
#endif /* _SYS_SA_H */