From: =?utf-8?q?Kristian_H=C3=B8gsberg?= Subject: [PATCH 6/6] firewire: Add ref-counting for sbp2_device and hold a ref while we have work scheduled. Date: Wed, 14 Mar 2007 17:34:58 -0400 Signed-off-by: Kristian Høgsberg Signed-off-by: Stefan Richter --- drivers/firewire/fw-sbp2.c | 42 ++++++++++++++++++++++++++++++------------ 1 files changed, 30 insertions(+), 12 deletions(-) diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c index 0c87724..d7940db 100644 --- a/drivers/firewire/fw-sbp2.c +++ b/drivers/firewire/fw-sbp2.c @@ -51,6 +51,7 @@ typedef void (*scsi_done_fn_t) (struct scsi_cmnd *); static const char sbp2_driver_name[] = "sbp2"; struct sbp2_device { + struct kref kref; struct fw_unit *unit; struct fw_address_handler address_handler; struct list_head orb_list; @@ -513,6 +514,22 @@ static int add_scsi_devices(struct fw_unit *unit); static void remove_scsi_devices(struct fw_unit *unit); static void sbp2_reconnect(struct work_struct *work); +static void +release_sbp2_device(struct kref *kref) +{ + struct sbp2_device *sd = container_of(kref, struct sbp2_device, kref); + + sbp2_send_management_orb(sd->unit, sd->node_id, sd->generation, + SBP2_LOGOUT_REQUEST, sd->login_id, NULL); + + remove_scsi_devices(sd->unit); + + fw_core_remove_address_handler(&sd->address_handler); + fw_notify("removed sbp2 unit %s\n", sd->unit->device.bus_id); + put_device(&sd->unit->device); + kfree(sd); +} + static void sbp2_login(struct work_struct *work) { struct sbp2_device *sd = @@ -537,6 +554,7 @@ static void sbp2_login(struct work_struct *work) fw_error("failed to login to %s\n", unit->device.bus_id); remove_scsi_devices(unit); + kref_put(&sd->kref, release_sbp2_device); } return; } @@ -577,6 +595,7 @@ static void sbp2_login(struct work_struct *work) * retry login on bus reset. */ PREPARE_DELAYED_WORK(&sd->work, sbp2_login); } + kref_put(&sd->kref, release_sbp2_device); } static int sbp2_probe(struct device *dev) @@ -595,6 +614,7 @@ static int sbp2_probe(struct device *dev) unit->device.driver_data = sd; sd->unit = unit; INIT_LIST_HEAD(&sd->orb_list); + kref_init(&sd->kref); sd->address_handler.length = 0x100; sd->address_handler.address_callback = sbp2_status_write; @@ -650,10 +670,14 @@ static int sbp2_probe(struct device *dev) unit->device.bus_id, sd->workarounds, firmware_revision, model); + get_device(&unit->device); + /* We schedule work to do the login so we can easily - * reschedule retries. */ + * reschedule retries. Always get the ref before scheduling + * work.*/ INIT_DELAYED_WORK(&sd->work, sbp2_login); - schedule_delayed_work(&sd->work, 0); + if (schedule_delayed_work(&sd->work, 0)) + kref_get(&sd->kref); return 0; } @@ -663,15 +687,7 @@ static int sbp2_remove(struct device *dev) struct fw_unit *unit = fw_unit(dev); struct sbp2_device *sd = unit->device.driver_data; - sbp2_send_management_orb(unit, sd->node_id, sd->generation, - SBP2_LOGOUT_REQUEST, sd->login_id, NULL); - - remove_scsi_devices(unit); - - fw_core_remove_address_handler(&sd->address_handler); - kfree(sd); - - fw_notify("removed sbp2 unit %s\n", dev->bus_id); + kref_put(&sd->kref, release_sbp2_device); return 0; } @@ -710,6 +726,7 @@ static void sbp2_reconnect(struct work_struct *work) unit->device.bus_id, sd->retries); sbp2_agent_reset(unit); sbp2_cancel_orbs(unit); + kref_put(&sd->kref, release_sbp2_device); } static void sbp2_update(struct fw_unit *unit) @@ -719,7 +736,8 @@ static void sbp2_update(struct fw_unit *unit) sd->retries = 0; fw_device_enable_phys_dma(device); - schedule_delayed_work(&sd->work, 0); + if (schedule_delayed_work(&sd->work, 0)) + kref_get(&sd->kref); } #define SBP2_UNIT_SPEC_ID_ENTRY 0x0000609e -- 1.4.4.2