diff options
| -rw-r--r-- | block/genhd.c | 544 | ||||
| -rw-r--r-- | drivers/cdrom/cdrom.c | 56 | ||||
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 13 | ||||
| -rw-r--r-- | drivers/scsi/sd.c | 10 | ||||
| -rw-r--r-- | drivers/scsi/sr.c | 174 | ||||
| -rw-r--r-- | drivers/scsi/sr.h | 3 | ||||
| -rw-r--r-- | drivers/scsi/sr_ioctl.c | 2 | ||||
| -rw-r--r-- | fs/block_dev.c | 41 | ||||
| -rw-r--r-- | fs/partitions/check.c | 89 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 4 | ||||
| -rw-r--r-- | include/linux/cdrom.h | 6 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 | ||||
| -rw-r--r-- | include/linux/genhd.h | 20 | ||||
| -rw-r--r-- | include/scsi/scsi.h | 1 |
14 files changed, 734 insertions, 230 deletions
diff --git a/block/genhd.c b/block/genhd.c index 399d37e..6a5b772 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -18,6 +18,7 @@ #include <linux/buffer_head.h> #include <linux/mutex.h> #include <linux/idr.h> +#include <linux/log2.h> #include "blk.h" @@ -35,6 +36,10 @@ static DEFINE_IDR(ext_devt_idr); static struct device_type disk_type; +static void disk_add_events(struct gendisk *disk); +static void disk_del_events(struct gendisk *disk); +static void disk_release_events(struct gendisk *disk); + /** * disk_get_part - get partition * @disk: disk to look partition from @@ -502,6 +507,64 @@ static int exact_lock(dev_t devt, void *data) return 0; } +void register_disk(struct gendisk *disk) +{ + struct device *ddev = disk_to_dev(disk); + struct block_device *bdev; + struct disk_part_iter piter; + struct hd_struct *part; + int err; + + ddev->parent = disk->driverfs_dev; + + dev_set_name(ddev, disk->disk_name); + + /* delay uevents, until we scanned partition table */ + dev_set_uevent_suppress(ddev, 1); + + if (device_add(ddev)) + return; + if (!sysfs_deprecated) { + err = sysfs_create_link(block_depr, &ddev->kobj, + kobject_name(&ddev->kobj)); + if (err) { + device_del(ddev); + return; + } + } + disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj); + disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj); + + /* No minors to use for partitions */ + if (!disk_partitionable(disk)) + goto exit; + + /* No such device (e.g., media were just removed) */ + if (!get_capacity(disk)) + goto exit; + + bdev = bdget_disk(disk, 0); + if (!bdev) + goto exit; + + bdev->bd_invalidated = 1; + err = blkdev_get(bdev, FMODE_READ, NULL); + if (err < 0) + goto exit; + blkdev_put(bdev, FMODE_READ); + +exit: + /* announce disk after possible partitions are created */ + dev_set_uevent_suppress(ddev, 0); + kobject_uevent(&ddev->kobj, KOBJ_ADD); + + /* announce possible partitions */ + disk_part_iter_init(&piter, disk, 0); + while ((part = disk_part_iter_next(&piter))) + kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD); + disk_part_iter_exit(&piter); +} + /** * add_disk - add partitioning information to kernel list * @disk: per-device partitioning information @@ -551,18 +614,48 @@ void add_disk(struct gendisk *disk) retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj, "bdi"); WARN_ON(retval); -} + disk_add_events(disk); +} EXPORT_SYMBOL(add_disk); -EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */ -void unlink_gendisk(struct gendisk *disk) +void del_gendisk(struct gendisk *disk) { + struct disk_part_iter piter; + struct hd_struct *part; + + disk_del_events(disk); + + /* invalidate stuff */ + disk_part_iter_init(&piter, disk, + DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE); + while ((part = disk_part_iter_next(&piter))) { + invalidate_partition(disk, part->partno); + delete_partition(disk, part->partno); + } + disk_part_iter_exit(&piter); + + invalidate_partition(disk, 0); + blk_free_devt(disk_to_dev(disk)->devt); + set_capacity(disk, 0); + disk->flags &= ~GENHD_FL_UP; + sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi"); bdi_unregister(&disk->queue->backing_dev_info); blk_unregister_queue(disk); blk_unregister_region(disk_devt(disk), disk->minors); + + part_stat_set_all(&disk->part0, 0); + disk->part0.stamp = 0; + + kobject_put(disk->part0.holder_dir); + kobject_put(disk->slave_dir); + disk->driverfs_dev = NULL; + if (!sysfs_deprecated) + sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); + device_del(disk_to_dev(disk)); } +EXPORT_SYMBOL(del_gendisk); /** * get_gendisk - get partitioning information for a given device @@ -1005,6 +1098,7 @@ static void disk_release(struct device *dev) { struct gendisk *disk = dev_to_disk(dev); + disk_release_events(disk); kfree(disk->random); disk_replace_part_tbl(disk, NULL); free_part_stats(&disk->part0); @@ -1110,29 +1204,6 @@ static int __init proc_genhd_init(void) module_init(proc_genhd_init); #endif /* CONFIG_PROC_FS */ -static void media_change_notify_thread(struct work_struct *work) -{ - struct gendisk *gd = container_of(work, struct gendisk, async_notify); - char event[] = "MEDIA_CHANGE=1"; - char *envp[] = { event, NULL }; - - /* - * set enviroment vars to indicate which event this is for - * so that user space will know to go check the media status. - */ - kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp); - put_device(gd->driverfs_dev); -} - -#if 0 -void genhd_media_change_notify(struct gendisk *disk) -{ - get_device(disk->driverfs_dev); - schedule_work(&disk->async_notify); -} -EXPORT_SYMBOL_GPL(genhd_media_change_notify); -#endif /* 0 */ - dev_t blk_lookup_devt(const char *name, int partno) { dev_t devt = MKDEV(0, 0); @@ -1200,8 +1271,6 @@ struct gendisk *alloc_disk_node(int minors, int node_id) disk_to_dev(disk)->class = &block_class; disk_to_dev(disk)->type = &disk_type; device_initialize(disk_to_dev(disk)); - INIT_WORK(&disk->async_notify, - media_change_notify_thread); } return disk; } @@ -1293,3 +1362,422 @@ int invalidate_partition(struct gendisk *disk, int partno) } EXPORT_SYMBOL(invalidate_partition); + +/* + * Disk events - monitor disk events like media change and eject request. + */ +struct disk_events { + struct list_head node; /* all disk_event's */ + struct gendisk *disk; /* the associated disk */ + spinlock_t lock; + + int block; /* event blocking depth */ + unsigned int pending; /* events already sent out */ + unsigned int clearing; /* events being cleared */ + + long poll_msecs; /* interval, -1 for default */ + struct delayed_work dwork; +}; + +static const char *disk_events_strs[] = { + [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change", + [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request", +}; + +static char *disk_uevents[] = { + [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1", + [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1", +}; + +/* list of all disk_events */ +static DEFINE_MUTEX(disk_events_mutex); +static LIST_HEAD(disk_events); + +/* disable in-kernel polling by default */ +static unsigned long disk_events_dfl_poll_msecs = 0; + +static unsigned long disk_events_poll_jiffies(struct gendisk *disk) +{ + struct disk_events *ev = disk->ev; + long intv_msecs = 0; + + /* + * If device-specific poll interval is set, always use it. If + * the default is being used, poll iff there are events which + * can't be monitored asynchronously. + */ + if (ev->poll_msecs >= 0) + intv_msecs = ev->poll_msecs; + else if (disk->events & ~disk->async_events) + intv_msecs = disk_events_dfl_poll_msecs; + + return msecs_to_jiffies(intv_msecs); +} + +static void __disk_block_events(struct gendisk *disk, bool sync) +{ + struct disk_events *ev = disk->ev; + unsigned long flags; + bool cancel; + + spin_lock_irqsave(&ev->lock, flags); + cancel = !ev->block++; + spin_unlock_irqrestore(&ev->lock, flags); + + if (cancel) { + if (sync) + cancel_delayed_work_sync(&disk->ev->dwork); + else + cancel_delayed_work(&disk->ev->dwork); + } +} + +static void __disk_unblock_events(struct gendisk *disk, bool check_now) +{ + struct disk_events *ev = disk->ev; + unsigned long intv; + unsigned long flags; + + spin_lock_irqsave(&ev->lock, flags); + + if (WARN_ON_ONCE(ev->block <= 0)) + goto out_unlock; + + if (--ev->block) + goto out_unlock; + + /* + * Not exactly a latency critical operation, set poll timer + * slack to 25% and kick event check. + */ + intv = disk_events_poll_jiffies(disk); + set_timer_slack(&ev->dwork.timer, intv / 4); + if (check_now) + queue_delayed_work(system_nrt_wq, &ev->dwork, 0); + else if (intv) + queue_delayed_work(system_nrt_wq, &ev->dwork, intv); +out_unlock: + spin_unlock_irqrestore(&ev->lock, flags); +} + +/** + * disk_block_events - block and flush disk event checking + * @disk: disk to block events for + * + * On return from this function, it is guaranteed that event checking + * isn't in progress and won't happen until unblocked by + * disk_unblock_events(). Events blocking is counted and the actual + * unblocking happens after the matching number of unblocks are done. + * + * Note that this intentionally does not block event checking from + * disk_clear_events(). + * + * CONTEXT: + * Might sleep. + */ +void disk_block_events(struct gendisk *disk) +{ + if (disk->ev) + __disk_block_events(disk, true); +} + +/** + * disk_unblock_events - unblock disk event checking + * @disk: disk to unblock events for + * + * Undo disk_block_events(). When the block count reaches zero, it + * starts events polling if configured. + * + * CONTEXT: + * Don't care. Safe to call from irq context. + */ +void disk_unblock_events(struct gendisk *disk) +{ + if (disk->ev) + __disk_unblock_events(disk, true); +} + +/** + * disk_check_events - schedule immediate event checking + * @disk: disk to check events for + * + * Schedule immediate event checking on @disk if not blocked. + * + * CONTEXT: + * Don't care. Safe to call from irq context. + */ +void disk_check_events(struct gendisk *disk) +{ + if (disk->ev) { + __disk_block_events(disk, false); + __disk_unblock_events(disk, true); + } +} +EXPORT_SYMBOL_GPL(disk_check_events); + +/** + * disk_clear_events - synchronously check, clear and return pending events + * @disk: disk to fetch and clear events from + * @mask: mask of events to be fetched and clearted + * + * Disk events are synchronously checked and pending events in @mask + * are cleared and returned. This ignores the block count. + * + * CONTEXT: + * Might sleep. + */ +unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask) +{ + const struct block_device_operations *bdops = disk->fops; + struct disk_events *ev = disk->ev; + unsigned int pending; + + if (!ev) { + /* for drivers still using the old ->media_changed method */ + if ((mask & DISK_EVENT_MEDIA_CHANGE) && + bdops->media_changed && bdops->media_changed(disk)) + return DISK_EVENT_MEDIA_CHANGE; + return 0; + } + + /* tell the workfn about the events being cleared */ + spin_lock_irq(&ev->lock); + ev->clearing |= mask; + spin_unlock_irq(&ev->lock); + + /* uncondtionally schedule event check and wait for it to finish */ + __disk_block_events(disk, true); + queue_delayed_work(system_nrt_wq, &ev->dwork, 0); + flush_delayed_work(&ev->dwork); + __disk_unblock_events(disk, false); + + /* then, fetch and clear pending events */ + spin_lock_irq(&ev->lock); + WARN_ON_ONCE(ev->clearing & mask); /* cleared by workfn */ + pending = ev->pending & mask; + ev->pending &= ~mask; + spin_unlock_irq(&ev->lock); + + return pending; +} + +static void disk_events_workfn(struct work_struct *work) +{ + struct delayed_work *dwork = to_delayed_work(work); + struct disk_events *ev = container_of(dwork, struct disk_events, dwork); + struct gendisk *disk = ev->disk; + char *envp[ARRAY_SIZE(disk_uevents) + 1] = { }; + unsigned int clearing = ev->clearing; + unsigned int events; + unsigned long intv; + int nr_events = 0, i; + + /* check events */ + events = disk->fops->check_events(disk, clearing); + + /* accumulate pending events and schedule next poll if necessary */ + spin_lock_irq(&ev->lock); + + events &= ~ev->pending; + ev->pending |= events; + ev->clearing &= ~clearing; + + intv = disk_events_poll_jiffies(disk); + if (!ev->block && intv) + queue_delayed_work(system_nrt_wq, &ev->dwork, intv); + + spin_unlock_irq(&ev->lock); + + /* tell userland about new events */ + for (i = 0; i < ARRAY_SIZE(disk_uevents); i++) + if (events & (1 << i)) + envp[nr_events++] = disk_uevents[i]; + + if (nr_events) + kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp); +} + +/* + * A disk events enabled device has the following sysfs nodes under + * its /sys/block/X/ directory. + * + * events : list of all supported events + * events_async : list of events which can be detected w/o polling + * events_poll_msecs : polling interval, 0: disable, -1: system default + */ +static ssize_t __disk_events_show(unsigned int events, char *buf) +{ + const char *delim = ""; + ssize_t pos = 0; + int i; + + for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++) + if (events & (1 << i)) { + pos += sprintf(buf + pos, "%s%s", + delim, disk_events_strs[i]); + delim = " "; + } + if (pos) + pos += sprintf(buf + pos, "\n"); + return pos; +} + +static ssize_t disk_events_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return __disk_events_show(disk->events, buf); +} + +static ssize_t disk_events_async_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return __disk_events_show(disk->async_events, buf); +} + +static ssize_t disk_events_poll_msecs_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return sprintf(buf, "%ld\n", disk->ev->poll_msecs); +} + +static ssize_t disk_events_poll_msecs_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct gendisk *disk = dev_to_disk(dev); + long intv; + + if (!count || !sscanf(buf, "%ld", &intv)) + return -EINVAL; + + if (intv < 0 && intv != -1) + return -EINVAL; + + __disk_block_events(disk, true); + disk->ev->poll_msecs = intv; + __disk_unblock_events(disk, true); + + return count; +} + +static const DEVICE_ATTR(events, S_IRUGO, disk_events_show, NULL); +static const DEVICE_ATTR(events_async, S_IRUGO, disk_events_async_show, NULL); +static const DEVICE_ATTR(events_poll_msecs, S_IRUGO|S_IWUSR, + disk_events_poll_msecs_show, + disk_events_poll_msecs_store); + +static const struct attribute *disk_events_attrs[] = { + &dev_attr_events.attr, + &dev_attr_events_async.attr, + &dev_attr_events_poll_msecs.attr, + NULL, +}; + +/* + * The default polling interval can be specified by the kernel + * parameter block.events_dfl_poll_msecs which defaults to 0 + * (disable). This can also be modified runtime by writing to + * /sys/module/block/events_dfl_poll_msecs. + */ +static int disk_events_set_dfl_poll_msecs(const char *val, + const struct kernel_param *kp) +{ + struct disk_events *ev; + int ret; + + ret = param_set_ulong(val, kp); + if (ret < 0) + return ret; + + mutex_lock(&disk_events_mutex); + + list_for_each_entry(ev, &disk_events, node) + disk_check_events(ev->disk); + + mutex_unlock(&disk_events_mutex); + + return 0; +} + +static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = { + .set = disk_events_set_dfl_poll_msecs, + .get = param_get_ulong, +}; + +#undef MODULE_PARAM_PREFIX +#define MODULE_PARAM_PREFIX "block." + +module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops, + &disk_events_dfl_poll_msecs, 0644); + +/* + * disk_{add|del|release}_events - initialize and destroy disk_events. + */ +static void disk_add_events(struct gendisk *disk) +{ + struct disk_events *ev; + + if (!disk->fops->check_events || !(disk->events | disk->async_events)) + return; + + ev = kzalloc(sizeof(*ev), GFP_KERNEL); + if (!ev) { + pr_warn("%s: failed to initialize events\n", disk->disk_name); + return; + } + + if (sysfs_create_files(&disk_to_dev(disk)->kobj, + disk_events_attrs) < 0) { + pr_warn("%s: failed to create sysfs files for events\n", + disk->disk_name); + kfree(ev); + return; + } + + disk->ev = ev; + + INIT_LIST_HEAD(&ev->node); + ev->disk = disk; + spin_lock_init(&ev->lock); + ev->block = 1; + ev->poll_msecs = -1; + INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn); + + mutex_lock(&disk_events_mutex); + list_add_tail(&ev->node, &disk_events); + mutex_unlock(&disk_events_mutex); + + /* + * Block count is initialized to 1 and the following initial + * unblock kicks it into action. + */ + __disk_unblock_events(disk, true); +} + +static void disk_del_events(struct gendisk *disk) +{ + if (!disk->ev) + return; + + __disk_block_events(disk, true); + + mutex_lock(&disk_events_mutex); + list_del_init(&disk->ev->node); + mutex_unlock(&disk_events_mutex); + + sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs); +} + +static void disk_release_events(struct gendisk *disk) +{ + /* the block count should be 1 from disk_del_events() */ + WARN_ON_ONCE(disk->ev && disk->ev->block != 1); + kfree(disk->ev); +} diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index af13c62d..14033a36 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -1348,7 +1348,10 @@ static int cdrom_select_disc(struct cdrom_device_info *cdi, int slot) if (!CDROM_CAN(CDC_SELECT_DISC)) return -EDRIVE_CANT_DO_THIS; - (void) cdi->ops->media_changed(cdi, slot); + if (cdi->ops->check_events) + cdi->ops->check_events(cdi, 0, slot); + else + cdi->ops->media_changed(cdi, slot); if (slot == CDSL_NONE) { /* set media changed bits, on both queues */ @@ -1392,6 +1395,42 @@ static int cdrom_select_disc(struct cdrom_device_info *cdi, int slot) return slot; } +/* + * As cdrom implements an extra ioctl consumer for media changed + * event, it needs to buffer ->check_events() output, such that event + * is not lost for both the usual VFS and ioctl paths. + * cdi->{vfs|ioctl}_events are used to buffer pending events for each + * path. + * + * XXX: Locking is non-existent. cdi->ops->check_events() can be + * called in parallel and buffering fields are accessed without any + * exclusion. The original media_changed code had the same problem. + * It might be better to simply deprecate CDROM_MEDIA_CHANGED ioctl + * and remove this cruft altogether. It doesn't have much usefulness + * at this point. + */ +static void cdrom_update_events(struct cdrom_device_info *cdi, + unsigned int clearing) +{ + unsigned int events; + + events = cdi->ops->check_events(cdi, clearing, CDSL_CURRENT); + cdi->vfs_events |= events; + cdi->ioctl_events |= events; +} + +unsigned int cdrom_check_events(struct cdrom_device_info *cdi, + unsigned int clearing) +{ + unsigned int events; + + cdrom_update_events(cdi, clearing); + events = cdi->vfs_events; + cdi->vfs_events = 0; + return events; +} +EXPORT_SYMBOL(cdrom_check_events); + /* We want to make media_changed accessible to the user through an * ioctl. The main problem now is that we must double-buffer the * low-level implementation, to assure that the VFS and the user both @@ -1403,15 +1442,26 @@ int media_changed(struct cdrom_device_info *cdi, int queue) { unsigned int mask = (1 << (queue & 1)); int ret = !!(cdi->mc_flags & mask); + bool changed; if (!CDROM_CAN(CDC_MEDIA_CHANGED)) - return ret; + return ret; + /* changed since last call? */ - if (cdi->ops->media_changed(cdi, CDSL_CURRENT)) { + if (cdi->ops->check_events) { + BUG_ON(!queue); /* shouldn't be called from VFS path */ + cdrom_update_events(cdi, DISK_EVENT_MEDIA_CHANGE); + changed = cdi->ioctl_events & DISK_EVENT_MEDIA_CHANGE; + cdi->ioctl_events = 0; + } else + changed = cdi->ops->media_changed(cdi, CDSL_CURRENT); + + if (changed) { cdi->mc_flags = 0x3; /* set bit on both queues */ ret |= 1; cdi->media_written = 0; } + cdi->mc_flags &= ~mask; /* clear bit */ return ret; } diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index eafeeda..13bf891 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1984,8 +1984,7 @@ EXPORT_SYMBOL(scsi_mode_sense); * in. * * Returns zero if unsuccessful or an error if TUR failed. For - * removable media, a return of NOT_READY or UNIT_ATTENTION is - * translated to success, with the ->changed flag updated. + * removable media, UNIT_ATTENTION sets ->changed flag. **/ int scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries, @@ -2012,16 +2011,6 @@ scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries, } while (scsi_sense_valid(sshdr) && sshdr->sense_key == UNIT_ATTENTION && --retries); - if (!sshdr) - /* could not allocate sense buffer, so can't process it */ - return result; - - if (sdev->removable && scsi_sense_valid(sshdr) && - (sshdr->sense_key == UNIT_ATTENTION || - sshdr->sense_key == NOT_READY)) { - sdev->changed = 1; - result = 0; - } if (!sshdr_external) kfree(sshdr); return result; diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index b9ab3a5..8d488a9 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1045,15 +1045,7 @@ static int sd_media_changed(struct gendisk *disk) sshdr); } - /* - * Unable to test, unit probably not ready. This usually - * means there is no disc in the drive. Mark as changed, - * and we will figure it out later once the drive is - * available again. - */ - if (retval || (scsi_sense_valid(sshdr) && - /* 0x3a is medium not present */ - sshdr->asc == 0x3a)) { + if (retval) { set_media_not_present(sdkp); retval = 1; goto out; diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index d7b383c..be6baf8 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -104,14 +104,15 @@ static void sr_release(struct cdrom_device_info *); static void get_sectorsize(struct scsi_cd *); static void get_capabilities(struct scsi_cd *); -static int sr_media_change(struct cdrom_device_info *, int); +static unsigned int sr_check_events(struct cdrom_device_info *cdi, + unsigned int clearing, int slot); static int sr_packet(struct cdrom_device_info *, struct packet_command *); static struct cdrom_device_ops sr_dops = { .open = sr_open, .release = sr_release, .drive_status = sr_drive_status, - .media_changed = sr_media_change, + .check_events = sr_check_events, .tray_move = sr_tray_move, .lock_door = sr_lock_door, .select_speed = sr_select_speed, @@ -165,90 +166,96 @@ static void scsi_cd_put(struct scsi_cd *cd) mutex_unlock(&sr_ref_mutex); } -/* identical to scsi_test_unit_ready except that it doesn't - * eat the NOT_READY returns for removable media */ -int sr_test_unit_ready(struct scsi_device *sdev, struct scsi_sense_hdr *sshdr) +static unsigned int sr_get_events(struct scsi_device *sdev) { - int retries = MAX_RETRIES; - int the_result; - u8 cmd[] = {TEST_UNIT_READY, 0, 0, 0, 0, 0 }; + u8 buf[8]; + u8 cmd[] = { GET_EVENT_STATUS_NOTIFICATION, + 1, /* polled */ + 0, 0, /* reserved */ + 1 << 4, /* notification class: media */ + 0, 0, /* reserved */ + 0, sizeof(buf), /* allocation length */ + 0, /* control */ + }; + struct event_header *eh = (void *)buf; + struct media_event_desc *med = (void *)(buf + 4); + struct scsi_sense_hdr sshdr; + int result; - /* issue TEST_UNIT_READY until the initial startup UNIT_ATTENTION - * conditions are gone, or a timeout happens - */ - do { - the_result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, - 0, sshdr, SR_TIMEOUT, - retries--, NULL); - if (scsi_sense_valid(sshdr) && - sshdr->sense_key == UNIT_ATTENTION) - sdev->changed = 1; - - } while (retries > 0 && - (!scsi_status_is_good(the_result) || - (scsi_sense_valid(sshdr) && - sshdr->sense_key == UNIT_ATTENTION))); - return the_result; + result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, sizeof(buf), + &sshdr, SR_TIMEOUT, MAX_RETRIES, NULL); + if (scsi_sense_valid(&sshdr) && sshdr.sense_key == UNIT_ATTENTION) + return DISK_EVENT_MEDIA_CHANGE; + + if (result || be16_to_cpu(eh->data_len) < sizeof(*med)) + return 0; + + if (eh->nea || eh->notification_class != 0x4) + return 0; + + if (med->media_event_code == 1) + return DISK_EVENT_EJECT_REQUEST; + else if (med->media_event_code == 2) + return DISK_EVENT_MEDIA_CHANGE; + return 0; } /* - * This function checks to see if the media has been changed in the - * CDROM drive. It is possible that we have already sensed a change, - * or the drive may have sensed one and not yet reported it. We must - * be ready for either case. This function always reports the current - * value of the changed bit. If flag is 0, then the changed bit is reset. - * This function could be done as an ioctl, but we would need to have - * an inode for that to work, and we do not always have one. + * This function checks to see if the media has been changed or eject + * button has been pressed. It is possible that we have already + * sensed a change, or the drive may have sensed one and not yet + * reported it. The past events are accumulated in sdev->changed and + * returned together with the current state. */ - -static int sr_media_change(struct cdrom_device_info *cdi, int slot) +static unsigned int sr_check_events(struct cdrom_device_info *cdi, + unsigned int clearing, int slot) { struct scsi_cd *cd = cdi->handle; - int retval; - struct scsi_sense_hdr *sshdr; + bool last_present; + struct scsi_sense_hdr sshdr; + unsigned int events; + int ret; - if (CDSL_CURRENT != slot) { - /* no changer support */ - return -EINVAL; - } + /* no changer support */ + if (CDSL_CURRENT != slot) + return 0; - sshdr = kzalloc(sizeof(*sshdr), GFP_KERNEL); - retval = sr_test_unit_ready(cd->device, sshdr); - if (retval || (scsi_sense_valid(sshdr) && - /* 0x3a is medium not present */ - sshdr->asc == 0x3a)) { - /* Media not present or unable to test, unit probably not - * ready. This usually means there is no disc in the drive. - * Mark as changed, and we will figure it out later once - * the drive is available again. - */ - cd->device->changed = 1; - /* This will force a flush, if called from check_disk_change */ - retval = 1; - goto out; - }; + events = sr_get_events(cd->device); + /* + * GET_EVENT_STATUS_NOTIFICATION is enough unless MEDIA_CHANGE + * is being cleared. Note that there are devices which hang + * if asked to execute TUR repeatedly. + */ + if (!(clearing & DISK_EVENT_MEDIA_CHANGE)) + goto skip_tur; + + /* let's see whether the media is there with TUR */ + last_present = cd->media_present; + ret = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr); + + /* + * Media is considered to be present if TUR succeeds or fails with + * sense data indicating something other than media-not-present + * (ASC 0x3a). + */ + cd->media_present = scsi_status_is_good(ret) || + (scsi_sense_valid(&sshdr) && sshdr.asc != 0x3a); - retval = cd->device->changed; - cd->device->changed = 0; - /* If the disk changed, the capacity will now be different, - * so we force a re-read of this information */ - if (retval) { - /* check multisession offset etc */ - sr_cd_check(cdi); - get_sectorsize(cd); + if (last_present != cd->media_present) + events |= DISK_EVENT_MEDIA_CHANGE; +skip_tur: + if (cd->device->changed) { + events |= DISK_EVENT_MEDIA_CHANGE; + cd->device->changed = 0; } -out: - /* Notify userspace, that media has changed. */ - if (retval != cd->previous_state) + /* for backward compatibility */ + if (events & DISK_EVENT_MEDIA_CHANGE) sdev_evt_send_simple(cd->device, SDEV_EVT_MEDIA_CHANGE, GFP_KERNEL); - cd->previous_state = retval; - kfree(sshdr); - - return retval; + return events; } - + /* * sr_done is the interrupt routine for the device driver. * @@ -533,10 +540,25 @@ out: return ret; } -static int sr_block_media_changed(struct gendisk *disk) +static unsigned int sr_block_check_events(struct gendisk *disk, + unsigned int clearing) { struct scsi_cd *cd = scsi_cd(disk); - return cdrom_media_changed(&cd->cdi); + return cdrom_check_events(&cd->cdi, clearing); +} + +static int sr_block_revalidate_disk(struct gendisk *disk) +{ + struct scsi_cd *cd = scsi_cd(disk); + struct scsi_sense_hdr sshdr; + + /* if the unit is not ready, nothing more to do */ + if (scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr)) + return 0; + + sr_cd_check(&cd->cdi); + get_sectorsize(cd); + return 0; } static const struct block_device_operations sr_bdops = @@ -545,7 +567,8 @@ static const struct block_device_operations sr_bdops = .open = sr_block_open, .release = sr_block_release, .ioctl = sr_block_ioctl, - .media_changed = sr_block_media_changed, + .check_events = sr_block_check_events, + .revalidate_disk = sr_block_revalidate_disk, /* * No compat_ioctl for now because sr_block_ioctl never * seems to pass arbitary ioctls down to host drivers. @@ -618,6 +641,7 @@ static int sr_probe(struct device *dev) sprintf(disk->disk_name, "sr%d", minor); disk->fops = &sr_bdops; disk->flags = GENHD_FL_CD; + disk->events = DISK_EVENT_MEDIA_CHANGE | DISK_EVENT_EJECT_REQUEST; blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT); @@ -627,7 +651,7 @@ static int sr_probe(struct device *dev) cd->disk = disk; cd->capacity = 0x1fffff; cd->device->changed = 1; /* force recheck CD type */ - cd->previous_state = 1; + cd->media_present = 1; cd->use = 1; cd->readcd_known = 0; cd->readcd_cdda = 0; @@ -780,7 +804,7 @@ static void get_capabilities(struct scsi_cd *cd) } /* eat unit attentions */ - sr_test_unit_ready(cd->device, &sshdr); + scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr); /* ask for mode page 0x2a */ rc = scsi_mode_sense(cd->device, 0, 0x2a, buffer, 128, diff --git a/drivers/scsi/sr.h b/drivers/scsi/sr.h index 1e144df..e036f1d 100644 --- a/drivers/scsi/sr.h +++ b/drivers/scsi/sr.h @@ -40,7 +40,7 @@ typedef struct scsi_cd { unsigned xa_flag:1; /* CD has XA sectors ? */ unsigned readcd_known:1; /* drive supports READ_CD (0xbe) */ unsigned readcd_cdda:1; /* reading audio data using READ_CD */ - unsigned previous_state:1; /* media has changed */ + unsigned media_present:1; /* media is present */ struct cdrom_device_info cdi; /* We hold gendisk and scsi_device references on probe and use * the refs on this kref to decide when to release them */ @@ -61,7 +61,6 @@ int sr_select_speed(struct cdrom_device_info *cdi, int speed); int sr_audio_ioctl(struct cdrom_device_info *, unsigned int, void *); int sr_is_xa(Scsi_CD *); -int sr_test_unit_ready(struct scsi_device *sdev, struct scsi_sense_hdr *sshdr); /* sr_vendor.c */ void sr_vendor_init(Scsi_CD *); diff --git a/drivers/scsi/sr_ioctl.c b/drivers/scsi/sr_ioctl.c index 3cd8ffb..8be3055 100644 --- a/drivers/scsi/sr_ioctl.c +++ b/drivers/scsi/sr_ioctl.c @@ -307,7 +307,7 @@ int sr_drive_status(struct cdrom_device_info *cdi, int slot) /* we have no changer support */ return -EINVAL; } - if (0 == sr_test_unit_ready(cd->device, &sshdr)) + if (!scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr)) return CDS_DISC_OK; /* SK/ASC/ASCQ of 2/4/1 means "unit is becoming ready" */ diff --git a/fs/block_dev.c b/fs/block_dev.c index c1c1b8c..6017389 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -948,10 +948,11 @@ int check_disk_change(struct block_device *bdev) { struct gendisk *disk = bdev->bd_disk; const struct block_device_operations *bdops = disk->fops; + unsigned int events; - if (!bdops->media_changed) - return 0; - if (!bdops->media_changed(bdev->bd_disk)) + events = disk_clear_events(disk, DISK_EVENT_MEDIA_CHANGE | + DISK_EVENT_EJECT_REQUEST); + if (!(events & DISK_EVENT_MEDIA_CHANGE)) return 0; flush_disk(bdev); @@ -1158,9 +1159,10 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder) if (whole) { /* finish claiming */ + mutex_lock(&bdev->bd_mutex); spin_lock(&bdev_lock); - if (res == 0) { + if (!res) { BUG_ON(!bd_may_claim(bdev, whole, holder)); /* * Note that for a whole device bd_holders @@ -1180,6 +1182,20 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder) wake_up_bit(&whole->bd_claiming, 0); spin_unlock(&bdev_lock); + + /* + * Block event polling for write claims. Any write + * holder makes the write_holder state stick until all + * are released. This is good enough and tracking + * individual writeable reference is too fragile given + * the way @mode is used in blkdev_get/put(). + */ + if (!res && (mode & FMODE_WRITE) && !bdev->bd_write_holder) { + bdev->bd_write_holder = true; + disk_block_events(bdev->bd_disk); + } + + mutex_unlock(&bdev->bd_mutex); bdput(whole); } @@ -1353,12 +1369,23 @@ int blkdev_put(struct block_device *bdev, fmode_t mode) spin_unlock(&bdev_lock); - /* if this was the last claim, holder link should go too */ - if (bdev_free) + /* + * If this was the last claim, remove holder link and + * unblock evpoll if it was a write holder. + */ + if (bdev_free) { bd_unlink_disk_holder(bdev); + if (bdev->bd_write_holder) { + disk_unblock_events(bdev->bd_disk); + bdev->bd_write_holder = false; + } else + disk_check_events(bdev->bd_disk); + } mutex_unlock(&bdev->bd_mutex); - } + } else + disk_check_events(bdev->bd_disk); + return __blkdev_put(bdev, mode, 0); } EXPORT_SYMBOL(blkdev_put); diff --git a/fs/partitions/check.c b/fs/partitions/check.c index 011520d..9c21119 100644 --- a/fs/partitions/check.c +++ b/fs/partitions/check.c @@ -522,65 +522,6 @@ out_put: return ERR_PTR(err); } -/* Not exported, helper to add_disk(). */ -void register_disk(struct gendisk *disk) -{ - struct device *ddev = disk_to_dev(disk); - struct block_device *bdev; - struct disk_part_iter piter; - struct hd_struct *part; - int err; - - ddev->parent = disk->driverfs_dev; - - dev_set_name(ddev, disk->disk_name); - - /* delay uevents, until we scanned partition table */ - dev_set_uevent_suppress(ddev, 1); - - if (device_add(ddev)) - return; - if (!sysfs_deprecated) { - err = sysfs_create_link(block_depr, &ddev->kobj, - kobject_name(&ddev->kobj)); - if (err) { - device_del(ddev); - return; - } - } - disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj); - disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj); - - /* No minors to use for partitions */ - if (!disk_partitionable(disk)) - goto exit; - - /* No such device (e.g., media were just removed) */ - if (!get_capacity(disk)) - goto exit; - - bdev = bdget_disk(disk, 0); - if (!bdev) - goto exit; - - bdev->bd_invalidated = 1; - err = blkdev_get(bdev, FMODE_READ, NULL); - if (err < 0) - goto exit; - blkdev_put(bdev, FMODE_READ); - -exit: - /* announce disk after possible partitions are created */ - dev_set_uevent_suppress(ddev, 0); - kobject_uevent(&ddev->kobj, KOBJ_ADD); - - /* announce possible partitions */ - disk_part_iter_init(&piter, disk, 0); - while ((part = disk_part_iter_next(&piter))) - kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD); - disk_part_iter_exit(&piter); -} - static bool disk_unlock_native_capacity(struct gendisk *disk) { const struct block_device_operations *bdops = disk->fops; @@ -743,33 +684,3 @@ fail: } EXPORT_SYMBOL(read_dev_sector); - -void del_gendisk(struct gendisk *disk) -{ - struct disk_part_iter piter; - struct hd_struct *part; - - /* invalidate stuff */ - disk_part_iter_init(&piter, disk, - DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE); - while ((part = disk_part_iter_next(&piter))) { - invalidate_partition(disk, part->partno); - delete_partition(disk, part->partno); - } - disk_part_iter_exit(&piter); - - invalidate_partition(disk, 0); - blk_free_devt(disk_to_dev(disk)->devt); - set_capacity(disk, 0); - disk->flags &= ~GENHD_FL_UP; - unlink_gendisk(disk); - part_stat_set_all(&disk->part0, 0); - disk->part0.stamp = 0; - - kobject_put(disk->part0.holder_dir); - kobject_put(disk->slave_dir); - disk->driverfs_dev = NULL; - if (!sysfs_deprecated) - sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); - device_del(disk_to_dev(disk)); -} diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 482a7fd..5730043 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -644,7 +644,6 @@ static inline void rq_flush_dcache_pages(struct request *rq) extern int blk_register_queue(struct gendisk *disk); extern void blk_unregister_queue(struct gendisk *disk); -extern void register_disk(struct gendisk *dev); extern void generic_make_request(struct bio *bio); extern void blk_rq_init(struct request_queue *q, struct request *rq); extern void blk_put_request(struct request *); @@ -1253,6 +1252,9 @@ struct block_device_operations { int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); int (*direct_access) (struct block_device *, sector_t, void **, unsigned long *); + unsigned int (*check_events) (struct gendisk *disk, + unsigned int clearing); + /* ->media_changed() is DEPRECATED, use ->check_events() instead */ int (*media_changed) (struct gendisk *); void (*unlock_native_capacity) (struct gendisk *); int (*revalidate_disk) (struct gendisk *); diff --git a/include/linux/cdrom.h b/include/linux/cdrom.h index 78e9047..35eae4b 100644 --- a/include/linux/cdrom.h +++ b/include/linux/cdrom.h @@ -946,6 +946,8 @@ struct cdrom_device_info { /* device-related storage */ unsigned int options : 30; /* options flags */ unsigned mc_flags : 2; /* media change buffer flags */ + unsigned int vfs_events; /* cached events for vfs path */ + unsigned int ioctl_events; /* cached events for ioctl path */ int use_count; /* number of times device opened */ char name[20]; /* name of the device type */ /* per-device flags */ @@ -965,6 +967,8 @@ struct cdrom_device_ops { int (*open) (struct cdrom_device_info *, int); void (*release) (struct cdrom_device_info *); int (*drive_status) (struct cdrom_device_info *, int); + unsigned int (*check_events) (struct cdrom_device_info *cdi, + unsigned int clearing, int slot); int (*media_changed) (struct cdrom_device_info *, int); int (*tray_move) (struct cdrom_device_info *, int); int (*lock_door) (struct cdrom_device_info *, int); @@ -993,6 +997,8 @@ extern int cdrom_open(struct cdrom_device_info *cdi, struct block_device *bdev, extern void cdrom_release(struct cdrom_device_info *cdi, fmode_t mode); extern int cdrom_ioctl(struct cdrom_device_info *cdi, struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg); +extern unsigned int cdrom_check_events(struct cdrom_device_info *cdi, + unsigned int clearing); extern int cdrom_media_changed(struct cdrom_device_info *); extern int register_cdrom(struct cdrom_device_info *cdi); diff --git a/include/linux/fs.h b/include/linux/fs.h index f485015..997d22e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -662,6 +662,7 @@ struct block_device { void * bd_claiming; void * bd_holder; int bd_holders; + bool bd_write_holder; #ifdef CONFIG_SYSFS struct gendisk * bd_holder_disk; /* for sysfs slave linkng */ #endif diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 2d04681..c0d5f69 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -128,6 +128,11 @@ struct hd_struct { #define GENHD_FL_EXT_DEVT 64 /* allow extended devt */ #define GENHD_FL_NATIVE_CAPACITY 128 +enum { + DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */ + DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */ +}; + #define BLK_SCSI_MAX_CMDS (256) #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) @@ -144,6 +149,8 @@ struct disk_part_tbl { struct hd_struct __rcu *part[]; }; +struct disk_events; + struct gendisk { /* major, first_minor and minors are input parameters only, * don't use directly. Use disk_devt() and disk_max_parts(). @@ -155,6 +162,10 @@ struct gendisk { char disk_name[DISK_NAME_LEN]; /* name of major driver */ char *(*devnode)(struct gendisk *gd, mode_t *mode); + + unsigned int events; /* supported events */ + unsigned int async_events; /* async events, subset of all */ + /* Array of pointers to partitions indexed by partno. * Protected with matching bdev lock but stat and other * non-critical accesses use RCU. Always access through @@ -172,9 +183,8 @@ struct gendisk { struct kobject *slave_dir; struct timer_rand_state *random; - atomic_t sync_io; /* RAID */ - struct work_struct async_notify; + struct disk_events *ev; #ifdef CONFIG_BLK_DEV_INTEGRITY struct blk_integrity *integrity; #endif @@ -396,7 +406,6 @@ extern void part_round_stats(int cpu, struct hd_struct *part); /* block/genhd.c */ extern void add_disk(struct gendisk *disk); extern void del_gendisk(struct gendisk *gp); -extern void unlink_gendisk(struct gendisk *gp); extern struct gendisk *get_gendisk(dev_t dev, int *partno); extern struct block_device *bdget_disk(struct gendisk *disk, int partno); @@ -408,6 +417,11 @@ static inline int get_disk_ro(struct gendisk *disk) return disk->part0.policy; } +extern void disk_block_events(struct gendisk *disk); +extern void disk_unblock_events(struct gendisk *disk); +extern void disk_check_events(struct gendisk *disk); +extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask); + /* drivers/char/random.c */ extern void add_disk_randomness(struct gendisk *disk); extern void rand_initialize_disk(struct gendisk *disk); diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h index 216af85..8675861 100644 --- a/include/scsi/scsi.h +++ b/include/scsi/scsi.h @@ -104,6 +104,7 @@ struct scsi_cmnd; #define UNMAP 0x42 #define READ_TOC 0x43 #define READ_HEADER 0x44 +#define GET_EVENT_STATUS_NOTIFICATION 0x4a #define LOG_SELECT 0x4c #define LOG_SENSE 0x4d #define XDWRITEREAD_10 0x53 |
