Add support for asynchronous zvol minor operations

zfsonlinux issue #2217 - zvol minor operations: check snapdev
property before traversing snapshots of a dataset

zfsonlinux issue #3681 - lock order inversion between zvol_open()
and dsl_pool_sync()...zvol_rename_minors()

Create a per-pool zvol taskq for asynchronous zvol tasks.
There are a few key design decisions to be aware of.

* Each taskq must be single threaded to ensure tasks are always
  processed in the order in which they were dispatched.

* There is a taskq per-pool in order to keep the pools independent.
  This way if one pool is suspended it will not impact another.

* The preferred location to dispatch a zvol minor task is a sync
  task.  In this context there is easy access to the spa_t and
  minimal error handling is required because the sync task must
  succeed.

Support for asynchronous zvol minor operations address issue #3681.

Signed-off-by: Boris Protopopov <boris.protopopov@actifio.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2217
Closes #3678
Closes #3681
This commit is contained in:
Boris Protopopov
2014-03-22 05:07:14 -04:00
committed by Brian Behlendorf
parent eb0856779f
commit a0bd735adb
12 changed files with 485 additions and 217 deletions
+2
View File
@@ -23,6 +23,7 @@
* Copyright (c) 2011, 2015 by Delphix. All rights reserved.
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
* Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
* Copyright (c) 2016 Actifio, Inc. All rights reserved.
*/
#ifndef _SYS_SPA_IMPL_H
@@ -253,6 +254,7 @@ struct spa {
uint64_t spa_errata; /* errata issues detected */
spa_stats_t spa_stats; /* assorted spa statistics */
hrtime_t spa_ccw_fail_time; /* Conf cache write fail time */
taskq_t *spa_zvol_taskq; /* Taskq for minor managment */
/*
* spa_refcount & spa_config_lock must be the last elements
+7 -8
View File
@@ -21,6 +21,7 @@
/*
* Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2016 Actifio, Inc. All rights reserved.
*/
#ifndef _SYS_ZVOL_H
@@ -31,24 +32,22 @@
#define ZVOL_OBJ 1ULL
#define ZVOL_ZAP_OBJ 2ULL
#ifdef _KERNEL
extern void zvol_create_minors(spa_t *spa, const char *name, boolean_t async);
extern void zvol_remove_minors(spa_t *spa, const char *name, boolean_t async);
extern void zvol_rename_minors(spa_t *spa, const char *oldname,
const char *newname, boolean_t async);
#ifdef _KERNEL
extern int zvol_check_volsize(uint64_t volsize, uint64_t blocksize);
extern int zvol_check_volblocksize(const char *name, uint64_t volblocksize);
extern int zvol_get_stats(objset_t *os, nvlist_t *nv);
extern boolean_t zvol_is_zvol(const char *);
extern void zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx);
extern int zvol_create_minor(const char *name);
extern int zvol_create_minors(const char *name);
extern int zvol_remove_minor(const char *name);
extern void zvol_remove_minors(const char *name);
extern void zvol_rename_minors(const char *oldname, const char *newname);
extern int zvol_set_volsize(const char *, uint64_t);
extern int zvol_set_volblocksize(const char *, uint64_t);
extern int zvol_set_snapdev(const char *, uint64_t);
extern int zvol_set_snapdev(const char *, zprop_source_t, uint64_t);
extern int zvol_init(void);
extern void zvol_fini(void);
#endif /* _KERNEL */
#endif /* _SYS_ZVOL_H */