diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/firewire/fw-device.c | 121 | ||||
| -rw-r--r-- | drivers/firewire/fw-device.h | 1 |
2 files changed, 100 insertions, 22 deletions
diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c index 2af5a8d1e01..0925d91b261 100644 --- a/drivers/firewire/fw-device.c +++ b/drivers/firewire/fw-device.c @@ -25,6 +25,7 @@ #include <linux/device.h> #include <linux/delay.h> #include <linux/idr.h> +#include <linux/jiffies.h> #include <linux/string.h> #include <linux/rwsem.h> #include <linux/semaphore.h> @@ -634,12 +635,38 @@ struct fw_device *fw_device_get_by_devt(dev_t devt) return device; } +/* + * These defines control the retry behavior for reading the config + * rom. It shouldn't be necessary to tweak these; if the device + * doesn't respond to a config rom read within 10 seconds, it's not + * going to respond at all. As for the initial delay, a lot of + * devices will be able to respond within half a second after bus + * reset. On the other hand, it's not really worth being more + * aggressive than that, since it scales pretty well; if 10 devices + * are plugged in, they're all getting read within one second. + */ + +#define MAX_RETRIES 10 +#define RETRY_DELAY (3 * HZ) +#define INITIAL_DELAY (HZ / 2) +#define SHUTDOWN_DELAY (2 * HZ) + static void fw_device_shutdown(struct work_struct *work) { struct fw_device *device = container_of(work, struct fw_device, work.work); int minor = MINOR(device->device.devt); + if (time_is_after_jiffies(device->card->reset_jiffies + SHUTDOWN_DELAY)) { + schedule_delayed_work(&device->work, SHUTDOWN_DELAY); + return; + } + + if (atomic_cmpxchg(&device->state, + FW_DEVICE_GONE, + FW_DEVICE_SHUTDOWN) != FW_DEVICE_GONE) + return; + fw_device_cdev_remove(device); device_for_each_child(&device->device, NULL, shutdown_unit); device_unregister(&device->device); @@ -647,6 +674,7 @@ static void fw_device_shutdown(struct work_struct *work) down_write(&fw_device_rwsem); idr_remove(&fw_device_idr, minor); up_write(&fw_device_rwsem); + fw_device_put(device); } @@ -654,25 +682,63 @@ static struct device_type fw_device_type = { .release = fw_device_release, }; +static void fw_device_update(struct work_struct *work); + /* - * These defines control the retry behavior for reading the config - * rom. It shouldn't be necessary to tweak these; if the device - * doesn't respond to a config rom read within 10 seconds, it's not - * going to respond at all. As for the initial delay, a lot of - * devices will be able to respond within half a second after bus - * reset. On the other hand, it's not really worth being more - * aggressive than that, since it scales pretty well; if 10 devices - * are plugged in, they're all getting read within one second. + * If a device was pending for deletion because its node went away but its + * bus info block and root directory header matches that of a newly discovered + * device, revive the existing fw_device. + * The newly allocated fw_device becomes obsolete instead. */ +static int lookup_existing_device(struct device *dev, void *data) +{ + struct fw_device *old = fw_device(dev); + struct fw_device *new = data; + struct fw_card *card = new->card; + int match = 0; + + down_read(&fw_device_rwsem); /* serialize config_rom access */ + spin_lock_irq(&card->lock); /* serialize node access */ + + if (memcmp(old->config_rom, new->config_rom, 6 * 4) == 0 && + atomic_cmpxchg(&old->state, + FW_DEVICE_GONE, + FW_DEVICE_RUNNING) == FW_DEVICE_GONE) { + struct fw_node *current_node = new->node; + struct fw_node *obsolete_node = old->node; + + new->node = obsolete_node; + new->node->data = new; + old->node = current_node; + old->node->data = old; + + old->max_speed = new->max_speed; + old->node_id = current_node->node_id; + smp_wmb(); /* update node_id before generation */ + old->generation = card->generation; + old->config_rom_retries = 0; + fw_notify("rediscovered device %s\n", dev_name(dev)); -#define MAX_RETRIES 10 -#define RETRY_DELAY (3 * HZ) -#define INITIAL_DELAY (HZ / 2) + PREPARE_DELAYED_WORK(&old->work, fw_device_update); + schedule_delayed_work(&old->work, 0); + + if (current_node == card->root_node) + fw_schedule_bm_work(card, 0); + + match = 1; + } + + spin_unlock_irq(&card->lock); + up_read(&fw_device_rwsem); + + return match; +} static void fw_device_init(struct work_struct *work) { struct fw_device *device = container_of(work, struct fw_device, work.work); + struct device *revived_dev; int minor, err; /* @@ -696,6 +762,15 @@ static void fw_device_init(struct work_struct *work) return; } + revived_dev = device_find_child(device->card->device, + device, lookup_existing_device); + if (revived_dev) { + put_device(revived_dev); + fw_device_release(&device->device); + + return; + } + device_initialize(&device->device); fw_device_get(device); @@ -734,9 +809,10 @@ static void fw_device_init(struct work_struct *work) * fw_node_event(). */ if (atomic_cmpxchg(&device->state, - FW_DEVICE_INITIALIZING, - FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN) { - fw_device_shutdown(work); + FW_DEVICE_INITIALIZING, + FW_DEVICE_RUNNING) == FW_DEVICE_GONE) { + PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown); + schedule_delayed_work(&device->work, SHUTDOWN_DELAY); } else { if (device->config_rom_retries) fw_notify("created device %s: GUID %08x%08x, S%d00, " @@ -847,8 +923,8 @@ static void fw_device_refresh(struct work_struct *work) case REREAD_BIB_UNCHANGED: if (atomic_cmpxchg(&device->state, - FW_DEVICE_INITIALIZING, - FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN) + FW_DEVICE_INITIALIZING, + FW_DEVICE_RUNNING) == FW_DEVICE_GONE) goto gone; fw_device_update(work); @@ -879,8 +955,8 @@ static void fw_device_refresh(struct work_struct *work) create_units(device); if (atomic_cmpxchg(&device->state, - FW_DEVICE_INITIALIZING, - FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN) + FW_DEVICE_INITIALIZING, + FW_DEVICE_RUNNING) == FW_DEVICE_GONE) goto gone; fw_notify("refreshed device %s\n", dev_name(&device->device)); @@ -890,8 +966,9 @@ static void fw_device_refresh(struct work_struct *work) give_up: fw_notify("giving up on refresh of device %s\n", dev_name(&device->device)); gone: - atomic_set(&device->state, FW_DEVICE_SHUTDOWN); - fw_device_shutdown(work); + atomic_set(&device->state, FW_DEVICE_GONE); + PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown); + schedule_delayed_work(&device->work, SHUTDOWN_DELAY); out: if (node_id == card->root_node->node_id) fw_schedule_bm_work(card, 0); @@ -995,9 +1072,9 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event) */ device = node->data; if (atomic_xchg(&device->state, - FW_DEVICE_SHUTDOWN) == FW_DEVICE_RUNNING) { + FW_DEVICE_GONE) == FW_DEVICE_RUNNING) { PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown); - schedule_delayed_work(&device->work, 0); + schedule_delayed_work(&device->work, SHUTDOWN_DELAY); } break; } diff --git a/drivers/firewire/fw-device.h b/drivers/firewire/fw-device.h index df51732608d..8ef6ec2ca21 100644 --- a/drivers/firewire/fw-device.h +++ b/drivers/firewire/fw-device.h @@ -28,6 +28,7 @@ enum fw_device_state { FW_DEVICE_INITIALIZING, FW_DEVICE_RUNNING, + FW_DEVICE_GONE, FW_DEVICE_SHUTDOWN, }; |