From 3ae31f6a7b6e442fc6a92f29330fbad230dc3992 Mon Sep 17 00:00:00 2001 From: Chandra Seetharaman Date: Wed, 21 Oct 2009 09:22:46 -0700 Subject: [PATCH] [SCSI] scsi_dh: Change the scsidh_activate interface to be asynchronous Make scsi_dh_activate() function asynchronous, by taking in two additional parameters, one is the callback function and the other is the data to call the callback function with. Signed-off-by: Chandra Seetharaman Signed-off-by: James Bottomley --- drivers/md/dm-mpath.c | 8 ++++---- drivers/scsi/device_handler/scsi_dh.c | 17 ++++++++++++----- drivers/scsi/device_handler/scsi_dh_alua.c | 7 +++++-- drivers/scsi/device_handler/scsi_dh_emc.c | 7 +++++-- drivers/scsi/device_handler/scsi_dh_hp_sw.c | 7 +++++-- drivers/scsi/device_handler/scsi_dh_rdac.c | 7 +++++-- include/scsi/scsi_device.h | 3 ++- include/scsi/scsi_dh.h | 6 ++++-- 8 files changed, 42 insertions(+), 20 deletions(-) diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 32d0b878eccc..dce971dbdfa3 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -1116,8 +1116,9 @@ static int pg_init_limit_reached(struct multipath *m, struct pgpath *pgpath) return limit_reached; } -static void pg_init_done(struct dm_path *path, int errors) +static void pg_init_done(void *data, int errors) { + struct dm_path *path = data; struct pgpath *pgpath = path_to_pgpath(path); struct priority_group *pg = pgpath->pg; struct multipath *m = pg->m; @@ -1183,12 +1184,11 @@ static void pg_init_done(struct dm_path *path, int errors) static void activate_path(struct work_struct *work) { - int ret; struct pgpath *pgpath = container_of(work, struct pgpath, activate_path); - ret = scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev)); - pg_init_done(&pgpath->path, ret); + scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev), + pg_init_done, &pgpath->path); } /* diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c index 3ee1cbc89479..6f7f798910e8 100644 --- a/drivers/scsi/device_handler/scsi_dh.c +++ b/drivers/scsi/device_handler/scsi_dh.c @@ -226,7 +226,7 @@ store_dh_state(struct device *dev, struct device_attribute *attr, * Activate a device handler */ if (scsi_dh->activate) - err = scsi_dh->activate(sdev); + err = scsi_dh->activate(sdev, NULL, NULL); else err = 0; } @@ -423,10 +423,17 @@ EXPORT_SYMBOL_GPL(scsi_unregister_device_handler); /* * scsi_dh_activate - activate the path associated with the scsi_device * corresponding to the given request queue. - * @q - Request queue that is associated with the scsi_device to be - * activated. + * Returns immediately without waiting for activation to be completed. + * @q - Request queue that is associated with the scsi_device to be + * activated. + * @fn - Function to be called upon completion of the activation. + * Function fn is called with data (below) and the error code. + * Function fn may be called from the same calling context. So, + * do not hold the lock in the caller which may be needed in fn. + * @data - data passed to the function fn upon completion. + * */ -int scsi_dh_activate(struct request_queue *q) +int scsi_dh_activate(struct request_queue *q, activate_complete fn, void *data) { int err = 0; unsigned long flags; @@ -445,7 +452,7 @@ int scsi_dh_activate(struct request_queue *q) return err; if (scsi_dh->activate) - err = scsi_dh->activate(sdev); + err = scsi_dh->activate(sdev, fn, data); put_device(&sdev->sdev_gendev); return err; } diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index b5cdefaf2608..e8a8928e58bc 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -652,7 +652,8 @@ out: * based on a certain policy. But until we actually encounter them it * should be okay. */ -static int alua_activate(struct scsi_device *sdev) +static int alua_activate(struct scsi_device *sdev, + activate_complete fn, void *data) { struct alua_dh_data *h = get_alua_data(sdev); int err = SCSI_DH_OK; @@ -667,7 +668,9 @@ static int alua_activate(struct scsi_device *sdev) err = alua_stpg(sdev, TPGS_STATE_OPTIMIZED, h); out: - return err; + if (fn) + fn(data, err); + return 0; } /* diff --git a/drivers/scsi/device_handler/scsi_dh_emc.c b/drivers/scsi/device_handler/scsi_dh_emc.c index 0cffe84976fe..61966750bd60 100644 --- a/drivers/scsi/device_handler/scsi_dh_emc.c +++ b/drivers/scsi/device_handler/scsi_dh_emc.c @@ -528,7 +528,8 @@ retry: return err; } -static int clariion_activate(struct scsi_device *sdev) +static int clariion_activate(struct scsi_device *sdev, + activate_complete fn, void *data) { struct clariion_dh_data *csdev = get_clariion_data(sdev); int result; @@ -559,7 +560,9 @@ done: csdev->port, lun_state[csdev->lun_state], csdev->default_sp + 'A'); - return result; + if (fn) + fn(data, result); + return 0; } /* * params - parameters in the following format diff --git a/drivers/scsi/device_handler/scsi_dh_hp_sw.c b/drivers/scsi/device_handler/scsi_dh_hp_sw.c index f7da7530875e..0aacafc96f21 100644 --- a/drivers/scsi/device_handler/scsi_dh_hp_sw.c +++ b/drivers/scsi/device_handler/scsi_dh_hp_sw.c @@ -268,7 +268,8 @@ static int hp_sw_prep_fn(struct scsi_device *sdev, struct request *req) * activate the passive path (and deactivate the * previously active one). */ -static int hp_sw_activate(struct scsi_device *sdev) +static int hp_sw_activate(struct scsi_device *sdev, + activate_complete fn, void *data) { int ret = SCSI_DH_OK; struct hp_sw_dh_data *h = get_hp_sw_data(sdev); @@ -283,7 +284,9 @@ static int hp_sw_activate(struct scsi_device *sdev) HP_SW_NAME); } - return ret; + if (fn) + fn(data, ret); + return 0; } static const struct scsi_dh_devlist hp_sw_dh_data_list[] = { diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c index 268189d31d9c..be362adbd8e7 100644 --- a/drivers/scsi/device_handler/scsi_dh_rdac.c +++ b/drivers/scsi/device_handler/scsi_dh_rdac.c @@ -568,7 +568,8 @@ done: return err; } -static int rdac_activate(struct scsi_device *sdev) +static int rdac_activate(struct scsi_device *sdev, + activate_complete fn, void *data) { struct rdac_dh_data *h = get_rdac_data(sdev); int err = SCSI_DH_OK; @@ -580,7 +581,9 @@ static int rdac_activate(struct scsi_device *sdev) if (h->lun_state == RDAC_LUN_UNOWNED) err = send_mode_select(sdev, h); done: - return err; + if (fn) + fn(data, err); + return 0; } static int rdac_prep_fn(struct scsi_device *sdev, struct request *req) diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 92c4c3bd916d..68d185c79bae 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -177,6 +177,7 @@ struct scsi_dh_devlist { char *model; }; +typedef void (*activate_complete)(void *, int); struct scsi_device_handler { /* Used by the infrastructure */ struct list_head list; /* list of scsi_device_handlers */ @@ -188,7 +189,7 @@ struct scsi_device_handler { int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *); int (*attach)(struct scsi_device *); void (*detach)(struct scsi_device *); - int (*activate)(struct scsi_device *); + int (*activate)(struct scsi_device *, activate_complete, void *); int (*prep_fn)(struct scsi_device *, struct request *); int (*set_params)(struct scsi_device *, const char *); }; diff --git a/include/scsi/scsi_dh.h b/include/scsi/scsi_dh.h index ff2407405b42..e3f2db212ddc 100644 --- a/include/scsi/scsi_dh.h +++ b/include/scsi/scsi_dh.h @@ -56,14 +56,16 @@ enum { SCSI_DH_DRIVER_MAX, }; #if defined(CONFIG_SCSI_DH) || defined(CONFIG_SCSI_DH_MODULE) -extern int scsi_dh_activate(struct request_queue *); +extern int scsi_dh_activate(struct request_queue *, activate_complete, void *); extern int scsi_dh_handler_exist(const char *); extern int scsi_dh_attach(struct request_queue *, const char *); extern void scsi_dh_detach(struct request_queue *); extern int scsi_dh_set_params(struct request_queue *, const char *); #else -static inline int scsi_dh_activate(struct request_queue *req) +static inline int scsi_dh_activate(struct request_queue *req, + activate_complete fn, void *data) { + fn(data, 0); return 0; } static inline int scsi_dh_handler_exist(const char *name)