static struct kobject *block_depr;
+/*
+ * Unique, monotonically increasing sequential number associated with block
+ * devices instances (i.e. incremented each time a device is attached).
+ * Associating uevents with block devices in userspace is difficult and racy:
+ * the uevent netlink socket is lossy, and on slow and overloaded systems has
+ * a very high latency.
+ * Block devices do not have exclusive owners in userspace, any process can set
+ * one up (e.g. loop devices). Moreover, device names can be reused (e.g. loop0
+ * can be reused again and again).
+ * A userspace process setting up a block device and watching for its events
+ * cannot thus reliably tell whether an event relates to the device it just set
+ * up or another earlier instance with the same name.
+ * This sequential number allows userspace processes to solve this problem, and
+ * uniquely associate an uevent to the lifetime to a device.
+ */
+static atomic64_t diskseq;
+
/* for extended dynamic devt allocation, currently only one major is used */
#define NR_EXT_DEVT (1 << MINORBITS)
static DEFINE_IDA(ext_devt_ida);
-static void disk_check_events(struct disk_events *ev,
- unsigned int *clearing_ptr);
-static void disk_alloc_events(struct gendisk *disk);
-static void disk_add_events(struct gendisk *disk);
-static void disk_del_events(struct gendisk *disk);
-static void disk_release_events(struct gendisk *disk);
-
void set_capacity(struct gendisk *disk, sector_t sectors)
{
struct block_device *bdev = disk->part0;
* initial capacity during probing.
*/
if (size == capacity ||
- (disk->flags & (GENHD_FL_UP | GENHD_FL_HIDDEN)) != GENHD_FL_UP)
+ !disk_live(disk) ||
+ (disk->flags & GENHD_FL_HIDDEN))
return false;
pr_info("%s: detected capacity change from %lld to %lld\n",
EXPORT_SYMBOL_GPL(set_capacity_and_notify);
/*
- * Format the device name of the indicated disk into the supplied buffer and
- * return a pointer to that same buffer for convenience.
+ * Format the device name of the indicated block device into the supplied buffer
+ * and return a pointer to that same buffer for convenience.
+ *
+ * Note: do not use this in new code, use the %pg specifier to sprintf and
+ * printk insted.
*/
-char *disk_name(struct gendisk *hd, int partno, char *buf)
+const char *bdevname(struct block_device *bdev, char *buf)
{
+ struct gendisk *hd = bdev->bd_disk;
+ int partno = bdev->bd_partno;
+
if (!partno)
snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
return buf;
}
-
-const char *bdevname(struct block_device *bdev, char *buf)
-{
- return disk_name(bdev->bd_disk, bdev->bd_partno, buf);
-}
EXPORT_SYMBOL(bdevname);
static void part_stat_read_all(struct block_device *part,
void (*probe)(dev_t devt);
} *major_names[BLKDEV_MAJOR_HASH_SIZE];
static DEFINE_MUTEX(major_names_lock);
+static DEFINE_SPINLOCK(major_names_spinlock);
/* index in the above - for now: assume no multimajor ranges */
static inline int major_to_index(unsigned major)
{
struct blk_major_name *dp;
- mutex_lock(&major_names_lock);
+ spin_lock(&major_names_spinlock);
for (dp = major_names[major_to_index(offset)]; dp; dp = dp->next)
if (dp->major == offset)
seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
- mutex_unlock(&major_names_lock);
+ spin_unlock(&major_names_spinlock);
}
#endif /* CONFIG_PROC_FS */
p->next = NULL;
index = major_to_index(major);
+ spin_lock(&major_names_spinlock);
for (n = &major_names[index]; *n; n = &(*n)->next) {
if ((*n)->major == major)
break;
*n = p;
else
ret = -EBUSY;
+ spin_unlock(&major_names_spinlock);
if (ret < 0) {
printk("register_blkdev: cannot get major %u for %s\n",
int index = major_to_index(major);
mutex_lock(&major_names_lock);
+ spin_lock(&major_names_spinlock);
for (n = &major_names[index]; *n; n = &(*n)->next)
if ((*n)->major == major)
break;
p = *n;
*n = p->next;
}
+ spin_unlock(&major_names_spinlock);
mutex_unlock(&major_names_lock);
kfree(p);
}
EXPORT_SYMBOL(unregister_blkdev);
-/**
- * blk_mangle_minor - scatter minor numbers apart
- * @minor: minor number to mangle
- *
- * Scatter consecutively allocated @minor number apart if MANGLE_DEVT
- * is enabled. Mangling twice gives the original value.
- *
- * RETURNS:
- * Mangled value.
- *
- * CONTEXT:
- * Don't care.
- */
-static int blk_mangle_minor(int minor)
-{
-#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
- int i;
-
- for (i = 0; i < MINORBITS / 2; i++) {
- int low = minor & (1 << i);
- int high = minor & (1 << (MINORBITS - 1 - i));
- int distance = MINORBITS - 1 - 2 * i;
-
- minor ^= low | high; /* clear both bits */
- low <<= distance; /* swap the positions */
- high >>= distance;
- minor |= low | high; /* and set */
- }
-#endif
- return minor;
-}
-
-/**
- * blk_alloc_devt - allocate a dev_t for a block device
- * @bdev: block device to allocate dev_t for
- * @devt: out parameter for resulting dev_t
- *
- * Allocate a dev_t for block device.
- *
- * RETURNS:
- * 0 on success, allocated dev_t is returned in *@devt. -errno on
- * failure.
- *
- * CONTEXT:
- * Might sleep.
- */
-int blk_alloc_devt(struct block_device *bdev, dev_t *devt)
+int blk_alloc_ext_minor(void)
{
- struct gendisk *disk = bdev->bd_disk;
int idx;
- /* in consecutive minor range? */
- if (bdev->bd_partno < disk->minors) {
- *devt = MKDEV(disk->major, disk->first_minor + bdev->bd_partno);
- return 0;
- }
-
idx = ida_alloc_range(&ext_devt_ida, 0, NR_EXT_DEVT, GFP_KERNEL);
- if (idx < 0)
- return idx == -ENOSPC ? -EBUSY : idx;
-
- *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
- return 0;
+ if (idx == -ENOSPC)
+ return -EBUSY;
+ return idx;
}
-/**
- * blk_free_devt - free a dev_t
- * @devt: dev_t to free
- *
- * Free @devt which was allocated using blk_alloc_devt().
- *
- * CONTEXT:
- * Might sleep.
- */
-void blk_free_devt(dev_t devt)
+void blk_free_ext_minor(unsigned int minor)
{
- if (MAJOR(devt) == BLOCK_EXT_MAJOR)
- ida_free(&ext_devt_ida, blk_mangle_minor(MINOR(devt)));
+ ida_free(&ext_devt_ida, minor);
}
static char *bdevt_str(dev_t devt, char *buf)
xa_for_each(&disk->part_tbl, idx, part) {
if (bdev_is_partition(part) && !bdev_nr_sectors(part))
continue;
- if (!bdgrab(part))
+ if (!kobject_get_unless_zero(&part->bd_device.kobj))
continue;
rcu_read_unlock();
kobject_uevent(bdev_kobj(part), action);
- bdput(part);
+ put_device(&part->bd_device);
rcu_read_lock();
}
rcu_read_unlock();
blkdev_put(bdev, FMODE_READ);
}
-static void register_disk(struct device *parent, struct gendisk *disk,
- const struct attribute_group **groups)
+/**
+ * device_add_disk - add disk information to kernel list
+ * @parent: parent device for the disk
+ * @disk: per-device partitioning information
+ * @groups: Additional per-device sysfs groups
+ *
+ * This function registers the partitioning information in @disk
+ * with the kernel.
+ */
+int device_add_disk(struct device *parent, struct gendisk *disk,
+ const struct attribute_group **groups)
+
{
struct device *ddev = disk_to_dev(disk);
- int err;
+ int ret;
- ddev->parent = parent;
+ /*
+ * The disk queue should now be all set with enough information about
+ * the device for the elevator code to pick an adequate default
+ * elevator if one is needed, that is, for devices requesting queue
+ * registration.
+ */
+ elevator_init_mq(disk->queue);
- dev_set_name(ddev, "%s", disk->disk_name);
+ /*
+ * If the driver provides an explicit major number it also must provide
+ * the number of minors numbers supported, and those will be used to
+ * setup the gendisk.
+ * Otherwise just allocate the device numbers for both the whole device
+ * and all partitions from the extended dev_t space.
+ */
+ if (disk->major) {
+ if (WARN_ON(!disk->minors))
+ return -EINVAL;
+
+ if (disk->minors > DISK_MAX_PARTS) {
+ pr_err("block: can't allocate more than %d partitions\n",
+ DISK_MAX_PARTS);
+ disk->minors = DISK_MAX_PARTS;
+ }
+ } else {
+ if (WARN_ON(disk->minors))
+ return -EINVAL;
+
+ ret = blk_alloc_ext_minor();
+ if (ret < 0)
+ return ret;
+ disk->major = BLOCK_EXT_MAJOR;
+ disk->first_minor = ret;
+ disk->flags |= GENHD_FL_EXT_DEVT;
+ }
+
+ ret = disk_alloc_events(disk);
+ if (ret)
+ goto out_free_ext_minor;
/* delay uevents, until we scanned partition table */
dev_set_uevent_suppress(ddev, 1);
- if (groups) {
- WARN_ON(ddev->groups);
- ddev->groups = groups;
- }
- if (device_add(ddev))
- return;
+ ddev->parent = parent;
+ ddev->groups = groups;
+ dev_set_name(ddev, "%s", disk->disk_name);
+ if (!(disk->flags & GENHD_FL_HIDDEN))
+ ddev->devt = MKDEV(disk->major, disk->first_minor);
+ ret = device_add(ddev);
+ if (ret)
+ goto out_disk_release_events;
if (!sysfs_deprecated) {
- err = sysfs_create_link(block_depr, &ddev->kobj,
+ ret = sysfs_create_link(block_depr, &ddev->kobj,
kobject_name(&ddev->kobj));
- if (err) {
- device_del(ddev);
- return;
- }
+ if (ret)
+ goto out_device_del;
}
/*
*/
pm_runtime_set_memalloc_noio(ddev, true);
+ ret = blk_integrity_add(disk);
+ if (ret)
+ goto out_del_block_link;
+
disk->part0->bd_holder_dir =
kobject_create_and_add("holders", &ddev->kobj);
+ if (!disk->part0->bd_holder_dir)
+ goto out_del_integrity;
disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
+ if (!disk->slave_dir)
+ goto out_put_holder_dir;
- if (disk->flags & GENHD_FL_HIDDEN)
- return;
-
- disk_scan_partitions(disk);
-
- /* announce the disk and partitions after all partitions are created */
- dev_set_uevent_suppress(ddev, 0);
- disk_uevent(disk, KOBJ_ADD);
-
- if (disk->queue->backing_dev_info->dev) {
- err = sysfs_create_link(&ddev->kobj,
- &disk->queue->backing_dev_info->dev->kobj,
- "bdi");
- WARN_ON(err);
- }
-}
-
-/**
- * __device_add_disk - add disk information to kernel list
- * @parent: parent device for the disk
- * @disk: per-device partitioning information
- * @groups: Additional per-device sysfs groups
- * @register_queue: register the queue if set to true
- *
- * This function registers the partitioning information in @disk
- * with the kernel.
- *
- * FIXME: error handling
- */
-static void __device_add_disk(struct device *parent, struct gendisk *disk,
- const struct attribute_group **groups,
- bool register_queue)
-{
- dev_t devt;
- int retval;
-
- /*
- * The disk queue should now be all set with enough information about
- * the device for the elevator code to pick an adequate default
- * elevator if one is needed, that is, for devices requesting queue
- * registration.
- */
- if (register_queue)
- elevator_init_mq(disk->queue);
-
- /* minors == 0 indicates to use ext devt from part0 and should
- * be accompanied with EXT_DEVT flag. Make sure all
- * parameters make sense.
- */
- WARN_ON(disk->minors && !(disk->major || disk->first_minor));
- WARN_ON(!disk->minors &&
- !(disk->flags & (GENHD_FL_EXT_DEVT | GENHD_FL_HIDDEN)));
-
- disk->flags |= GENHD_FL_UP;
-
- retval = blk_alloc_devt(disk->part0, &devt);
- if (retval) {
- WARN_ON(1);
- return;
- }
- disk->major = MAJOR(devt);
- disk->first_minor = MINOR(devt);
+ ret = bd_register_pending_holders(disk);
+ if (ret < 0)
+ goto out_put_slave_dir;
- disk_alloc_events(disk);
+ ret = blk_register_queue(disk);
+ if (ret)
+ goto out_put_slave_dir;
if (disk->flags & GENHD_FL_HIDDEN) {
/*
disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
disk->flags |= GENHD_FL_NO_PART_SCAN;
} else {
- struct backing_dev_info *bdi = disk->queue->backing_dev_info;
- struct device *dev = disk_to_dev(disk);
- int ret;
-
- /* Register BDI before referencing it from bdev */
- dev->devt = devt;
- ret = bdi_register(bdi, "%u:%u", MAJOR(devt), MINOR(devt));
- WARN_ON(ret);
- bdi_set_owner(bdi, dev);
- bdev_add(disk->part0, devt);
- }
- register_disk(parent, disk, groups);
- if (register_queue)
- blk_register_queue(disk);
+ ret = bdi_register(disk->bdi, "%u:%u",
+ disk->major, disk->first_minor);
+ if (ret)
+ goto out_unregister_queue;
+ bdi_set_owner(disk->bdi, ddev);
+ ret = sysfs_create_link(&ddev->kobj,
+ &disk->bdi->dev->kobj, "bdi");
+ if (ret)
+ goto out_unregister_bdi;
+
+ bdev_add(disk->part0, ddev->devt);
+ disk_scan_partitions(disk);
- /*
- * Take an extra ref on queue which will be put on disk_release()
- * so that it sticks around as long as @disk is there.
- */
- WARN_ON_ONCE(!blk_get_queue(disk->queue));
+ /*
+ * Announce the disk and partitions after all partitions are
+ * created. (for hidden disks uevents remain suppressed forever)
+ */
+ dev_set_uevent_suppress(ddev, 0);
+ disk_uevent(disk, KOBJ_ADD);
+ }
+ disk_update_readahead(disk);
disk_add_events(disk);
- blk_integrity_add(disk);
-}
-
-void device_add_disk(struct device *parent, struct gendisk *disk,
- const struct attribute_group **groups)
+ return 0;
-{
- __device_add_disk(parent, disk, groups, true);
+out_unregister_bdi:
+ if (!(disk->flags & GENHD_FL_HIDDEN))
+ bdi_unregister(disk->bdi);
+out_unregister_queue:
+ blk_unregister_queue(disk);
+out_put_slave_dir:
+ kobject_put(disk->slave_dir);
+out_put_holder_dir:
+ kobject_put(disk->part0->bd_holder_dir);
+out_del_integrity:
+ blk_integrity_del(disk);
+out_del_block_link:
+ if (!sysfs_deprecated)
+ sysfs_remove_link(block_depr, dev_name(ddev));
+out_device_del:
+ device_del(ddev);
+out_disk_release_events:
+ disk_release_events(disk);
+out_free_ext_minor:
+ if (disk->major == BLOCK_EXT_MAJOR)
+ blk_free_ext_minor(disk->first_minor);
+ return WARN_ON_ONCE(ret); /* keep until all callers handle errors */
}
EXPORT_SYMBOL(device_add_disk);
-void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk)
-{
- __device_add_disk(parent, disk, NULL, false);
-}
-EXPORT_SYMBOL(device_add_disk_no_queue_reg);
-
/**
* del_gendisk - remove the gendisk
* @disk: the struct gendisk to remove
{
might_sleep();
- if (WARN_ON_ONCE(!disk->queue))
+ if (WARN_ON_ONCE(!disk_live(disk) && !(disk->flags & GENHD_FL_HIDDEN)))
return;
blk_integrity_del(disk);
disk_del_events(disk);
- mutex_lock(&disk->part0->bd_mutex);
- disk->flags &= ~GENHD_FL_UP;
+ mutex_lock(&disk->open_mutex);
+ remove_inode_hash(disk->part0->bd_inode);
blk_drop_partitions(disk);
- mutex_unlock(&disk->part0->bd_mutex);
+ mutex_unlock(&disk->open_mutex);
fsync_bdev(disk->part0);
__invalidate_device(disk->part0, true);
- /*
- * Unhash the bdev inode for this device so that it can't be looked
- * up any more even if openers still hold references to it.
- */
- remove_inode_hash(disk->part0->bd_inode);
-
set_capacity(disk, 0);
if (!(disk->flags & GENHD_FL_HIDDEN)) {
* Unregister bdi before releasing device numbers (as they can
* get reused and we'd get clashes in sysfs).
*/
- bdi_unregister(disk->queue->backing_dev_info);
+ bdi_unregister(disk->bdi);
}
blk_unregister_queue(disk);
request_module("block-major-%d", MAJOR(devt));
}
-/**
- * bdget_disk - do bdget() by gendisk and partition number
- * @disk: gendisk of interest
- * @partno: partition number
- *
- * Find partition @partno from @disk, do bdget() on it.
- *
- * CONTEXT:
- * Don't care.
- *
- * RETURNS:
- * Resulting block_device on success, NULL on failure.
- */
-struct block_device *bdget_disk(struct gendisk *disk, int partno)
-{
- struct block_device *bdev = NULL;
-
- rcu_read_lock();
- bdev = xa_load(&disk->part_tbl, partno);
- if (bdev && !bdgrab(bdev))
- bdev = NULL;
- rcu_read_unlock();
-
- return bdev;
-}
-
/*
* print a full list of all partitions - intended for places where the root
* filesystem can't be mounted and thus to give the victim some idea of what
while ((dev = class_dev_iter_next(&iter))) {
struct gendisk *disk = dev_to_disk(dev);
struct block_device *part;
- char name_buf[BDEVNAME_SIZE];
char devt_buf[BDEVT_SIZE];
unsigned long idx;
xa_for_each(&disk->part_tbl, idx, part) {
if (!bdev_nr_sectors(part))
continue;
- printk("%s%s %10llu %s %s",
+ printk("%s%s %10llu %pg %s",
bdev_is_partition(part) ? " " : "",
bdevt_str(part->bd_dev, devt_buf),
- bdev_nr_sectors(part) >> 1,
- disk_name(disk, part->bd_partno, name_buf),
+ bdev_nr_sectors(part) >> 1, part,
part->bd_meta_info ?
part->bd_meta_info->uuid : "");
if (bdev_is_partition(part))
struct gendisk *sgp = v;
struct block_device *part;
unsigned long idx;
- char buf[BDEVNAME_SIZE];
/* Don't show non-partitionable removeable devices or empty devices */
if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
xa_for_each(&sgp->part_tbl, idx, part) {
if (!bdev_nr_sectors(part))
continue;
- seq_printf(seqf, "%4d %7d %10llu %s\n",
+ seq_printf(seqf, "%4d %7d %10llu %pg\n",
MAJOR(part->bd_dev), MINOR(part->bd_dev),
- bdev_nr_sectors(part) >> 1,
- disk_name(sgp, part->bd_partno, buf));
+ bdev_nr_sectors(part) >> 1, part);
}
rcu_read_unlock();
return 0;
return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
}
+static ssize_t diskseq_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gendisk *disk = dev_to_disk(dev);
+
+ return sprintf(buf, "%llu\n", disk->diskseq);
+}
+
static DEVICE_ATTR(range, 0444, disk_range_show, NULL);
static DEVICE_ATTR(ext_range, 0444, disk_ext_range_show, NULL);
static DEVICE_ATTR(removable, 0444, disk_removable_show, NULL);
static DEVICE_ATTR(stat, 0444, part_stat_show, NULL);
static DEVICE_ATTR(inflight, 0444, part_inflight_show, NULL);
static DEVICE_ATTR(badblocks, 0644, disk_badblocks_show, disk_badblocks_store);
+static DEVICE_ATTR(diskseq, 0444, diskseq_show, NULL);
#ifdef CONFIG_FAIL_MAKE_REQUEST
ssize_t part_fail_show(struct device *dev,
&dev_attr_stat.attr,
&dev_attr_inflight.attr,
&dev_attr_badblocks.attr,
+ &dev_attr_events.attr,
+ &dev_attr_events_async.attr,
+ &dev_attr_events_poll_msecs.attr,
+ &dev_attr_diskseq.attr,
#ifdef CONFIG_FAIL_MAKE_REQUEST
&dev_attr_fail.attr,
#endif
might_sleep();
- blk_free_devt(dev->devt);
disk_release_events(disk);
kfree(disk->random);
xa_destroy(&disk->part_tbl);
- bdput(disk->part0);
- if (disk->queue)
- blk_put_queue(disk->queue);
- kfree(disk);
+ disk->queue->disk = NULL;
+ blk_put_queue(disk->queue);
+ iput(disk->part0->bd_inode); /* frees the disk */
}
+
+static int block_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct gendisk *disk = dev_to_disk(dev);
+
+ return add_uevent_var(env, "DISKSEQ=%llu", disk->diskseq);
+}
+
struct class block_class = {
.name = "block",
+ .dev_uevent = block_uevent,
};
static char *block_devnode(struct device *dev, umode_t *mode,
{
struct gendisk *gp = v;
struct block_device *hd;
- char buf[BDEVNAME_SIZE];
unsigned int inflight;
struct disk_stats stat;
unsigned long idx;
else
inflight = part_in_flight(hd);
- seq_printf(seqf, "%4d %7d %s "
+ seq_printf(seqf, "%4d %7d %pg "
"%lu %lu %lu %u "
"%lu %lu %lu %u "
"%u %u %u "
"%lu %lu %lu %u "
"%lu %u"
"\n",
- MAJOR(hd->bd_dev), MINOR(hd->bd_dev),
- disk_name(gp, hd->bd_partno, buf),
+ MAJOR(hd->bd_dev), MINOR(hd->bd_dev), hd,
stat.ios[STAT_READ],
stat.merges[STAT_READ],
stat.sectors[STAT_READ],
module_init(proc_genhd_init);
#endif /* CONFIG_PROC_FS */
+dev_t part_devt(struct gendisk *disk, u8 partno)
+{
+ struct block_device *part;
+ dev_t devt = 0;
+
+ rcu_read_lock();
+ part = xa_load(&disk->part_tbl, partno);
+ if (part)
+ devt = part->bd_dev;
+ rcu_read_unlock();
+
+ return devt;
+}
+
dev_t blk_lookup_devt(const char *name, int partno)
{
dev_t devt = MKDEV(0, 0);
class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
while ((dev = class_dev_iter_next(&iter))) {
struct gendisk *disk = dev_to_disk(dev);
- struct block_device *part;
if (strcmp(dev_name(dev), name))
continue;
*/
devt = MKDEV(MAJOR(dev->devt),
MINOR(dev->devt) + partno);
- break;
- }
- part = bdget_disk(disk, partno);
- if (part) {
- devt = part->bd_dev;
- bdput(part);
- break;
+ } else {
+ devt = part_devt(disk, partno);
+ if (devt)
+ break;
}
}
class_dev_iter_exit(&iter);
return devt;
}
-struct gendisk *__alloc_disk_node(int minors, int node_id)
+struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
+ struct lock_class_key *lkclass)
{
struct gendisk *disk;
- if (minors > DISK_MAX_PARTS) {
- printk(KERN_ERR
- "block: can't allocate more than %d partitions\n",
- DISK_MAX_PARTS);
- minors = DISK_MAX_PARTS;
- }
+ if (!blk_get_queue(q))
+ return NULL;
disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
if (!disk)
- return NULL;
+ goto out_put_queue;
+
+ disk->bdi = bdi_alloc(node_id);
+ if (!disk->bdi)
+ goto out_free_disk;
disk->part0 = bdev_alloc(disk, 0);
if (!disk->part0)
- goto out_free_disk;
+ goto out_free_bdi;
disk->node_id = node_id;
+ mutex_init(&disk->open_mutex);
xa_init(&disk->part_tbl);
if (xa_insert(&disk->part_tbl, 0, disk->part0, GFP_KERNEL))
goto out_destroy_part_tbl;
- disk->minors = minors;
rand_initialize_disk(disk);
disk_to_dev(disk)->class = &block_class;
disk_to_dev(disk)->type = &disk_type;
device_initialize(disk_to_dev(disk));
+ inc_diskseq(disk);
+ disk->queue = q;
+ q->disk = disk;
+ lockdep_init_map(&disk->lockdep_map, "(bio completion)", lkclass, 0);
+#ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
+ INIT_LIST_HEAD(&disk->slave_bdevs);
+#endif
return disk;
out_destroy_part_tbl:
xa_destroy(&disk->part_tbl);
- bdput(disk->part0);
+ iput(disk->part0->bd_inode);
+out_free_bdi:
+ bdi_put(disk->bdi);
out_free_disk:
kfree(disk);
+out_put_queue:
+ blk_put_queue(q);
return NULL;
}
EXPORT_SYMBOL(__alloc_disk_node);
+struct gendisk *__blk_alloc_disk(int node, struct lock_class_key *lkclass)
+{
+ struct request_queue *q;
+ struct gendisk *disk;
+
+ q = blk_alloc_queue(node);
+ if (!q)
+ return NULL;
+
+ disk = __alloc_disk_node(q, node, lkclass);
+ if (!disk) {
+ blk_cleanup_queue(q);
+ return NULL;
+ }
+ return disk;
+}
+EXPORT_SYMBOL(__blk_alloc_disk);
+
/**
* put_disk - decrements the gendisk refcount
* @disk: the struct gendisk to decrement the refcount for
}
EXPORT_SYMBOL(put_disk);
+/**
+ * blk_cleanup_disk - shutdown a gendisk allocated by blk_alloc_disk
+ * @disk: gendisk to shutdown
+ *
+ * Mark the queue hanging off @disk DYING, drain all pending requests, then mark
+ * the queue DEAD, destroy and put it and the gendisk structure.
+ *
+ * Context: can sleep
+ */
+void blk_cleanup_disk(struct gendisk *disk)
+{
+ blk_cleanup_queue(disk->queue);
+ put_disk(disk);
+}
+EXPORT_SYMBOL(blk_cleanup_disk);
+
static void set_disk_ro_uevent(struct gendisk *gd, int ro)
{
char event[] = "DISK_RO=1";
}
EXPORT_SYMBOL(bdev_read_only);
-/*
- * 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;
-
- struct mutex block_mutex; /* protects blocking */
- 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;
-
-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 if the POLL flag is set.
- */
- if (ev->poll_msecs >= 0)
- intv_msecs = ev->poll_msecs;
- else if (disk->event_flags & DISK_EVENT_FLAG_POLL)
- intv_msecs = disk_events_dfl_poll_msecs;
-
- return msecs_to_jiffies(intv_msecs);
-}
-
-/**
- * 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)
-{
- struct disk_events *ev = disk->ev;
- unsigned long flags;
- bool cancel;
-
- if (!ev)
- return;
-
- /*
- * Outer mutex ensures that the first blocker completes canceling
- * the event work before further blockers are allowed to finish.
- */
- mutex_lock(&ev->block_mutex);
-
- spin_lock_irqsave(&ev->lock, flags);
- cancel = !ev->block++;
- spin_unlock_irqrestore(&ev->lock, flags);
-
- if (cancel)
- cancel_delayed_work_sync(&disk->ev->dwork);
-
- mutex_unlock(&ev->block_mutex);
-}
-
-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;
-
- intv = disk_events_poll_jiffies(disk);
- if (check_now)
- queue_delayed_work(system_freezable_power_efficient_wq,
- &ev->dwork, 0);
- else if (intv)
- queue_delayed_work(system_freezable_power_efficient_wq,
- &ev->dwork, intv);
-out_unlock:
- spin_unlock_irqrestore(&ev->lock, flags);
-}
-
-/**
- * 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, false);
-}
-
-/**
- * disk_flush_events - schedule immediate event checking and flushing
- * @disk: disk to check and flush events for
- * @mask: events to flush
- *
- * Schedule immediate event checking on @disk if not blocked. Events in
- * @mask are scheduled to be cleared from the driver. Note that this
- * doesn't clear the events from @disk->ev.
- *
- * CONTEXT:
- * If @mask is non-zero must be called with bdev->bd_mutex held.
- */
-void disk_flush_events(struct gendisk *disk, unsigned int mask)
-{
- struct disk_events *ev = disk->ev;
-
- if (!ev)
- return;
-
- spin_lock_irq(&ev->lock);
- ev->clearing |= mask;
- if (!ev->block)
- mod_delayed_work(system_freezable_power_efficient_wq,
- &ev->dwork, 0);
- spin_unlock_irq(&ev->lock);
-}
-
-/**
- * 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 cleared
- *
- * Disk events are synchronously checked and pending events in @mask
- * are cleared and returned. This ignores the block count.
- *
- * CONTEXT:
- * Might sleep.
- */
-static unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
-{
- struct disk_events *ev = disk->ev;
- unsigned int pending;
- unsigned int clearing = mask;
-
- if (!ev)
- return 0;
-
- disk_block_events(disk);
-
- /*
- * store the union of mask and ev->clearing on the stack so that the
- * race with disk_flush_events does not cause ambiguity (ev->clearing
- * can still be modified even if events are blocked).
- */
- spin_lock_irq(&ev->lock);
- clearing |= ev->clearing;
- ev->clearing = 0;
- spin_unlock_irq(&ev->lock);
-
- disk_check_events(ev, &clearing);
- /*
- * if ev->clearing is not 0, the disk_flush_events got called in the
- * middle of this function, so we want to run the workfn without delay.
- */
- __disk_unblock_events(disk, ev->clearing ? true : false);
-
- /* then, fetch and clear pending events */
- spin_lock_irq(&ev->lock);
- pending = ev->pending & mask;
- ev->pending &= ~mask;
- spin_unlock_irq(&ev->lock);
- WARN_ON_ONCE(clearing & mask);
-
- return pending;
-}
-
-/**
- * bdev_check_media_change - check if a removable media has been changed
- * @bdev: block device to check
- *
- * Check whether a removable media has been changed, and attempt to free all
- * dentries and inodes and invalidates all block device page cache entries in
- * that case.
- *
- * Returns %true if the block device changed, or %false if not.
- */
-bool bdev_check_media_change(struct block_device *bdev)
-{
- unsigned int events;
-
- events = disk_clear_events(bdev->bd_disk, DISK_EVENT_MEDIA_CHANGE |
- DISK_EVENT_EJECT_REQUEST);
- if (!(events & DISK_EVENT_MEDIA_CHANGE))
- return false;
-
- if (__invalidate_device(bdev, true))
- pr_warn("VFS: busy inodes on changed media %s\n",
- bdev->bd_disk->disk_name);
- set_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state);
- return true;
-}
-EXPORT_SYMBOL(bdev_check_media_change);
-
-/*
- * Separate this part out so that a different pointer for clearing_ptr can be
- * passed in for disk_clear_events.
- */
-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);
-
- disk_check_events(ev, &ev->clearing);
-}
-
-static void disk_check_events(struct disk_events *ev,
- unsigned int *clearing_ptr)
-{
- struct gendisk *disk = ev->disk;
- char *envp[ARRAY_SIZE(disk_uevents) + 1] = { };
- unsigned int clearing = *clearing_ptr;
- 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;
- *clearing_ptr &= ~clearing;
-
- intv = disk_events_poll_jiffies(disk);
- if (!ev->block && intv)
- queue_delayed_work(system_freezable_power_efficient_wq,
- &ev->dwork, intv);
-
- spin_unlock_irq(&ev->lock);
-
- /*
- * Tell userland about new events. Only the events listed in
- * @disk->events are reported, and only if DISK_EVENT_FLAG_UEVENT
- * is set. Otherwise, events are processed internally but never
- * get reported to userland.
- */
- for (i = 0; i < ARRAY_SIZE(disk_uevents); i++)
- if ((events & disk->events & (1 << i)) &&
- (disk->event_flags & DISK_EVENT_FLAG_UEVENT))
- 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
- * (always empty, only for backwards compatibility)
- * 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);
-
- if (!(disk->event_flags & DISK_EVENT_FLAG_UEVENT))
- return 0;
-
- return __disk_events_show(disk->events, buf);
-}
-
-static ssize_t disk_events_async_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- return 0;
-}
-
-static ssize_t disk_events_poll_msecs_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct gendisk *disk = dev_to_disk(dev);
-
- if (!disk->ev)
- return sprintf(buf, "-1\n");
-
- 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;
-
- if (!disk->ev)
- return -ENODEV;
-
- disk_block_events(disk);
- disk->ev->poll_msecs = intv;
- __disk_unblock_events(disk, true);
-
- return count;
-}
-
-static const DEVICE_ATTR(events, 0444, disk_events_show, NULL);
-static const DEVICE_ATTR(events_async, 0444, disk_events_async_show, NULL);
-static const DEVICE_ATTR(events_poll_msecs, 0644,
- 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/parameters/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_flush_events(ev->disk, 0);
-
- 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_{alloc|add|del|release}_events - initialize and destroy disk_events.
- */
-static void disk_alloc_events(struct gendisk *disk)
-{
- struct disk_events *ev;
-
- if (!disk->fops->check_events || !disk->events)
- return;
-
- ev = kzalloc(sizeof(*ev), GFP_KERNEL);
- if (!ev) {
- pr_warn("%s: failed to initialize events\n", disk->disk_name);
- return;
- }
-
- INIT_LIST_HEAD(&ev->node);
- ev->disk = disk;
- spin_lock_init(&ev->lock);
- mutex_init(&ev->block_mutex);
- ev->block = 1;
- ev->poll_msecs = -1;
- INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn);
-
- disk->ev = ev;
-}
-
-static void disk_add_events(struct gendisk *disk)
-{
- /* FIXME: error handling */
- 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);
-
- if (!disk->ev)
- return;
-
- mutex_lock(&disk_events_mutex);
- list_add_tail(&disk->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) {
- disk_block_events(disk);
-
- 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)
+void inc_diskseq(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);
+ disk->diskseq = atomic64_inc_return(&diskseq);
}
projects / linux-2.6-microblaze.git / blobdiff