From edb39c9deda87da5aad9c090e2e8eaf8470c852c Mon Sep 17 00:00:00 2001 From: Goldwyn Rodrigues Date: Sat, 29 Mar 2014 10:01:53 -0500 Subject: [PATCH] Introduce md_cluster_operations to handle cluster functions This allows dynamic registering of cluster hooks. Signed-off-by: Goldwyn Rodrigues --- drivers/md/md-cluster.c | 18 +++++++++++++++++ drivers/md/md-cluster.h | 15 ++++++++++++++ drivers/md/md.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++ drivers/md/md.h | 7 +++++++ 4 files changed, 92 insertions(+) create mode 100644 drivers/md/md-cluster.h diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c index bc8ea9d..e223560 100644 --- a/drivers/md/md-cluster.c +++ b/drivers/md/md-cluster.c @@ -13,6 +13,7 @@ #include #include #include "md.h" +#include "md-cluster.h" #define LVB_SIZE 64 @@ -113,15 +114,32 @@ static void lockres_free(struct dlm_lock_resource *res) kfree(res); } +static int join(struct mddev *mddev, int nodes) +{ + return 0; +} + +static int leave(struct mddev *mddev) +{ + return 0; +} + +static struct md_cluster_operations cluster_ops = { + .join = join, + .leave = leave, +}; + static int __init cluster_init(void) { pr_warn("md-cluster: EXPERIMENTAL. Use with caution\n"); pr_info("Registering Cluster MD functions\n"); + register_md_cluster_operations(&cluster_ops, THIS_MODULE); return 0; } static void cluster_exit(void) { + unregister_md_cluster_operations(); } module_init(cluster_init); diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h new file mode 100644 index 0000000..aa9f07b --- /dev/null +++ b/drivers/md/md-cluster.h @@ -0,0 +1,15 @@ + + +#ifndef _MD_CLUSTER_H +#define _MD_CLUSTER_H + +#include "md.h" + +struct mddev; + +struct md_cluster_operations { + int (*join)(struct mddev *mddev); + int (*leave)(struct mddev *mddev); +}; + +#endif /* _MD_CLUSTER_H */ diff --git a/drivers/md/md.c b/drivers/md/md.c index c8d2bac..57ecb51 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -53,6 +53,7 @@ #include #include "md.h" #include "bitmap.h" +#include "md-cluster.h" #ifndef MODULE static void autostart_arrays(int part); @@ -66,6 +67,10 @@ static void autostart_arrays(int part); static LIST_HEAD(pers_list); static DEFINE_SPINLOCK(pers_lock); +struct md_cluster_operations *md_cluster_ops; +struct module *md_cluster_mod; +EXPORT_SYMBOL(md_cluster_mod); + static DECLARE_WAIT_QUEUE_HEAD(resync_wait); static struct workqueue_struct *md_wq; static struct workqueue_struct *md_misc_wq; @@ -7231,6 +7236,53 @@ int unregister_md_personality(struct md_personality *p) } EXPORT_SYMBOL(unregister_md_personality); +int register_md_cluster_operations(struct md_cluster_operations *ops, struct module *module) +{ + if (md_cluster_ops != NULL) + return -EALREADY; + spin_lock(&pers_lock); + md_cluster_ops = ops; + md_cluster_mod = module; + spin_unlock(&pers_lock); + return 0; +} +EXPORT_SYMBOL(register_md_cluster_operations); + +int unregister_md_cluster_operations(void) +{ + spin_lock(&pers_lock); + md_cluster_ops = NULL; + spin_unlock(&pers_lock); + return 0; +} +EXPORT_SYMBOL(unregister_md_cluster_operations); + +int md_setup_cluster(struct mddev *mddev, int nodes) +{ + int err; + + err = request_module("md-cluster"); + if (err) { + pr_err("md-cluster module not found.\n"); + return err; + } + + spin_lock(&pers_lock); + if (!md_cluster_ops || !try_module_get(md_cluster_mod)) { + spin_unlock(&pers_lock); + return -ENOENT; + } + spin_unlock(&pers_lock); + + return md_cluster_ops->join(mddev); +} + +void md_cluster_stop(struct mddev *mddev) +{ + md_cluster_ops->leave(mddev); + module_put(md_cluster_mod); +} + static int is_mddev_idle(struct mddev *mddev, int init) { struct md_rdev *rdev; diff --git a/drivers/md/md.h b/drivers/md/md.h index 318ca8f..0185931 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -23,6 +23,7 @@ #include #include #include +#include "md-cluster.h" #define MaxSector (~(sector_t)0) @@ -608,6 +609,11 @@ static inline void safe_put_page(struct page *p) extern int register_md_personality(struct md_personality *p); extern int unregister_md_personality(struct md_personality *p); +extern int register_md_cluster_operations(struct md_cluster_operations *ops, + struct module *module); +extern int unregister_md_cluster_operations(void); +extern int md_setup_cluster(struct mddev *mddev, int nodes); +extern void md_cluster_stop(struct mddev *mddev); extern struct md_thread *md_register_thread( void (*run)(struct md_thread *thread), struct mddev *mddev, @@ -669,4 +675,5 @@ static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev) } } +extern struct md_cluster_operations *md_cluster_ops; #endif /* _MD_MD_H */ -- 2.7.4