| /* |
| * gendisk handling |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/fs.h> |
| #include <linux/genhd.h> |
| #include <linux/kdev_t.h> |
| #include <linux/kernel.h> |
| #include <linux/blkdev.h> |
| #include <linux/init.h> |
| #include <linux/spinlock.h> |
| #include <linux/seq_file.h> |
| #include <linux/slab.h> |
| #include <linux/kmod.h> |
| #include <linux/kobj_map.h> |
| #include <linux/buffer_head.h> |
| #include <linux/mutex.h> |
| |
| static DEFINE_MUTEX(block_class_lock); |
| #ifndef CONFIG_SYSFS_DEPRECATED |
| struct kobject *block_depr; |
| #endif |
| |
| /* |
| * Can be deleted altogether. Later. |
| * |
| */ |
| static struct blk_major_name { |
| struct blk_major_name *next; |
| int major; |
| char name[16]; |
| } *major_names[BLKDEV_MAJOR_HASH_SIZE]; |
| |
| /* index in the above - for now: assume no multimajor ranges */ |
| static inline int major_to_index(int major) |
| { |
| return major % BLKDEV_MAJOR_HASH_SIZE; |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| void blkdev_show(struct seq_file *f, off_t offset) |
| { |
| struct blk_major_name *dp; |
| |
| if (offset < BLKDEV_MAJOR_HASH_SIZE) { |
| mutex_lock(&block_class_lock); |
| for (dp = major_names[offset]; dp; dp = dp->next) |
| seq_printf(f, "%3d %s\n", dp->major, dp->name); |
| mutex_unlock(&block_class_lock); |
| } |
| } |
| #endif /* CONFIG_PROC_FS */ |
| |
| int register_blkdev(unsigned int major, const char *name) |
| { |
| struct blk_major_name **n, *p; |
| int index, ret = 0; |
| |
| mutex_lock(&block_class_lock); |
| |
| /* temporary */ |
| if (major == 0) { |
| for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { |
| if (major_names[index] == NULL) |
| break; |
| } |
| |
| if (index == 0) { |
| printk("register_blkdev: failed to get major for %s\n", |
| name); |
| ret = -EBUSY; |
| goto out; |
| } |
| major = index; |
| ret = major; |
| } |
| |
| p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL); |
| if (p == NULL) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| p->major = major; |
| strlcpy(p->name, name, sizeof(p->name)); |
| p->next = NULL; |
| index = major_to_index(major); |
| |
| for (n = &major_names[index]; *n; n = &(*n)->next) { |
| if ((*n)->major == major) |
| break; |
| } |
| if (!*n) |
| *n = p; |
| else |
| ret = -EBUSY; |
| |
| if (ret < 0) { |
| printk("register_blkdev: cannot get major %d for %s\n", |
| major, name); |
| kfree(p); |
| } |
| out: |
| mutex_unlock(&block_class_lock); |
| return ret; |
| } |
| |
| EXPORT_SYMBOL(register_blkdev); |
| |
| void unregister_blkdev(unsigned int major, const char *name) |
| { |
| struct blk_major_name **n; |
| struct blk_major_name *p = NULL; |
| int index = major_to_index(major); |
| |
| mutex_lock(&block_class_lock); |
| for (n = &major_names[index]; *n; n = &(*n)->next) |
| if ((*n)->major == major) |
| break; |
| if (!*n || strcmp((*n)->name, name)) { |
| WARN_ON(1); |
| } else { |
| p = *n; |
| *n = p->next; |
| } |
| mutex_unlock(&block_class_lock); |
| kfree(p); |
| } |
| |
| EXPORT_SYMBOL(unregister_blkdev); |
| |
| static struct kobj_map *bdev_map; |
| |
| /* |
| * Register device numbers dev..(dev+range-1) |
| * range must be nonzero |
| * The hash chain is sorted on range, so that subranges can override. |
| */ |
| void blk_register_region(dev_t devt, unsigned long range, struct module *module, |
| struct kobject *(*probe)(dev_t, int *, void *), |
| int (*lock)(dev_t, void *), void *data) |
| { |
| kobj_map(bdev_map, devt, range, module, probe, lock, data); |
| } |
| |
| EXPORT_SYMBOL(blk_register_region); |
| |
| void blk_unregister_region(dev_t devt, unsigned long range) |
| { |
| kobj_unmap(bdev_map, devt, range); |
| } |
| |
| EXPORT_SYMBOL(blk_unregister_region); |
| |
| static struct kobject *exact_match(dev_t devt, int *part, void *data) |
| { |
| struct gendisk *p = data; |
| |
| return &p->dev.kobj; |
| } |
| |
| static int exact_lock(dev_t devt, void *data) |
| { |
| struct gendisk *p = data; |
| |
| if (!get_disk(p)) |
| return -1; |
| return 0; |
| } |
| |
| /** |
| * add_disk - add partitioning information to kernel list |
| * @disk: per-device partitioning information |
| * |
| * This function registers the partitioning information in @disk |
| * with the kernel. |
| */ |
| void add_disk(struct gendisk *disk) |
| { |
| disk->flags |= GENHD_FL_UP; |
| blk_register_region(MKDEV(disk->major, disk->first_minor), |
| disk->minors, NULL, exact_match, exact_lock, disk); |
| register_disk(disk); |
| blk_register_queue(disk); |
| } |
| |
| EXPORT_SYMBOL(add_disk); |
| EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */ |
| |
| void unlink_gendisk(struct gendisk *disk) |
| { |
| blk_unregister_queue(disk); |
| blk_unregister_region(MKDEV(disk->major, disk->first_minor), |
| disk->minors); |
| } |
| |
| /** |
| * get_gendisk - get partitioning information for a given device |
| * @dev: device to get partitioning information for |
| * |
| * This function gets the structure containing partitioning |
| * information for the given device @dev. |
| */ |
| struct gendisk *get_gendisk(dev_t devt, int *part) |
| { |
| struct kobject *kobj = kobj_lookup(bdev_map, devt, part); |
| struct device *dev = kobj_to_dev(kobj); |
| |
| return kobj ? dev_to_disk(dev) : NULL; |
| } |
| |
| /* |
| * 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 |
| * went wrong |
| */ |
| void __init printk_all_partitions(void) |
| { |
| struct device *dev; |
| struct gendisk *sgp; |
| char buf[BDEVNAME_SIZE]; |
| int n; |
| |
| mutex_lock(&block_class_lock); |
| /* For each block device... */ |
| list_for_each_entry(dev, &block_class.devices, node) { |
| if (dev->type != &disk_type) |
| continue; |
| sgp = dev_to_disk(dev); |
| /* |
| * Don't show empty devices or things that have been surpressed |
| */ |
| if (get_capacity(sgp) == 0 || |
| (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)) |
| continue; |
| |
| /* |
| * Note, unlike /proc/partitions, I am showing the numbers in |
| * hex - the same format as the root= option takes. |
| */ |
| printk("%02x%02x %10llu %s", |
| sgp->major, sgp->first_minor, |
| (unsigned long long)get_capacity(sgp) >> 1, |
| disk_name(sgp, 0, buf)); |
| if (sgp->driverfs_dev != NULL && |
| sgp->driverfs_dev->driver != NULL) |
| printk(" driver: %s\n", |
| sgp->driverfs_dev->driver->name); |
| else |
| printk(" (driver?)\n"); |
| |
| /* now show the partitions */ |
| for (n = 0; n < sgp->minors - 1; ++n) { |
| if (sgp->part[n] == NULL) |
| continue; |
| if (sgp->part[n]->nr_sects == 0) |
| continue; |
| printk(" %02x%02x %10llu %s\n", |
| sgp->major, n + 1 + sgp->first_minor, |
| (unsigned long long)sgp->part[n]->nr_sects >> 1, |
| disk_name(sgp, n + 1, buf)); |
| } |
| } |
| |
| mutex_unlock(&block_class_lock); |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| /* iterator */ |
| static void *part_start(struct seq_file *part, loff_t *pos) |
| { |
| loff_t k = *pos; |
| struct device *dev; |
| |
| mutex_lock(&block_class_lock); |
| list_for_each_entry(dev, &block_class.devices, node) { |
| if (dev->type != &disk_type) |
| continue; |
| if (!k--) |
| return dev_to_disk(dev); |
| } |
| return NULL; |
| } |
| |
| static void *part_next(struct seq_file *part, void *v, loff_t *pos) |
| { |
| struct gendisk *gp = v; |
| struct device *dev; |
| ++*pos; |
| list_for_each_entry(dev, &gp->dev.node, node) { |
| if (&dev->node == &block_class.devices) |
| return NULL; |
| if (dev->type == &disk_type) |
| return dev_to_disk(dev); |
| } |
| return NULL; |
| } |
| |
| static void part_stop(struct seq_file *part, void *v) |
| { |
| mutex_unlock(&block_class_lock); |
| } |
| |
| static int show_partition(struct seq_file *part, void *v) |
| { |
| struct gendisk *sgp = v; |
| int n; |
| char buf[BDEVNAME_SIZE]; |
| |
| if (&sgp->dev.node == block_class.devices.next) |
| seq_puts(part, "major minor #blocks name\n\n"); |
| |
| /* Don't show non-partitionable removeable devices or empty devices */ |
| if (!get_capacity(sgp) || |
| (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE))) |
| return 0; |
| if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO) |
| return 0; |
| |
| /* show the full disk and all non-0 size partitions of it */ |
| seq_printf(part, "%4d %4d %10llu %s\n", |
| sgp->major, sgp->first_minor, |
| (unsigned long long)get_capacity(sgp) >> 1, |
| disk_name(sgp, 0, buf)); |
| for (n = 0; n < sgp->minors - 1; n++) { |
| if (!sgp->part[n]) |
| continue; |
| if (sgp->part[n]->nr_sects == 0) |
| continue; |
| seq_printf(part, "%4d %4d %10llu %s\n", |
| sgp->major, n + 1 + sgp->first_minor, |
| (unsigned long long)sgp->part[n]->nr_sects >> 1 , |
| disk_name(sgp, n + 1, buf)); |
| } |
| |
| return 0; |
| } |
| |
| struct seq_operations partitions_op = { |
| .start = part_start, |
| .next = part_next, |
| .stop = part_stop, |
| .show = show_partition |
| }; |
| #endif |
| |
| |
| extern int blk_dev_init(void); |
| |
| static struct kobject *base_probe(dev_t devt, int *part, void *data) |
| { |
| if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0) |
| /* Make old-style 2.4 aliases work */ |
| request_module("block-major-%d", MAJOR(devt)); |
| return NULL; |
| } |
| |
| static int __init genhd_device_init(void) |
| { |
| class_register(&block_class); |
| bdev_map = kobj_map_init(base_probe, &block_class_lock); |
| blk_dev_init(); |
| |
| #ifndef CONFIG_SYSFS_DEPRECATED |
| /* create top-level block dir */ |
| block_depr = kobject_create_and_add("block", NULL); |
| #endif |
| return 0; |
| } |
| |
| subsys_initcall(genhd_device_init); |
| |
| static ssize_t disk_range_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| |
| return sprintf(buf, "%d\n", disk->minors); |
| } |
| |
| static ssize_t disk_removable_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| |
| return sprintf(buf, "%d\n", |
| (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); |
| } |
| |
| static ssize_t disk_size_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| |
| return sprintf(buf, "%llu\n", (unsigned long long)get_capacity(disk)); |
| } |
| |
| static ssize_t disk_capability_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| |
| return sprintf(buf, "%x\n", disk->flags); |
| } |
| |
| static ssize_t disk_stat_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| |
| preempt_disable(); |
| disk_round_stats(disk); |
| preempt_enable(); |
| return sprintf(buf, |
| "%8lu %8lu %8llu %8u " |
| "%8lu %8lu %8llu %8u " |
| "%8u %8u %8u" |
| "\n", |
| disk_stat_read(disk, ios[READ]), |
| disk_stat_read(disk, merges[READ]), |
| (unsigned long long)disk_stat_read(disk, sectors[READ]), |
| jiffies_to_msecs(disk_stat_read(disk, ticks[READ])), |
| disk_stat_read(disk, ios[WRITE]), |
| disk_stat_read(disk, merges[WRITE]), |
| (unsigned long long)disk_stat_read(disk, sectors[WRITE]), |
| jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])), |
| disk->in_flight, |
| jiffies_to_msecs(disk_stat_read(disk, io_ticks)), |
| jiffies_to_msecs(disk_stat_read(disk, time_in_queue))); |
| } |
| |
| #ifdef CONFIG_FAIL_MAKE_REQUEST |
| static ssize_t disk_fail_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| |
| return sprintf(buf, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0); |
| } |
| |
| static ssize_t disk_fail_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| int i; |
| |
| if (count > 0 && sscanf(buf, "%d", &i) > 0) { |
| if (i == 0) |
| disk->flags &= ~GENHD_FL_FAIL; |
| else |
| disk->flags |= GENHD_FL_FAIL; |
| } |
| |
| return count; |
| } |
| |
| #endif |
| |
| static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL); |
| static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL); |
| static DEVICE_ATTR(size, S_IRUGO, disk_size_show, NULL); |
| static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL); |
| static DEVICE_ATTR(stat, S_IRUGO, disk_stat_show, NULL); |
| #ifdef CONFIG_FAIL_MAKE_REQUEST |
| static struct device_attribute dev_attr_fail = |
| __ATTR(make-it-fail, S_IRUGO|S_IWUSR, disk_fail_show, disk_fail_store); |
| #endif |
| |
| static struct attribute *disk_attrs[] = { |
| &dev_attr_range.attr, |
| &dev_attr_removable.attr, |
| &dev_attr_size.attr, |
| &dev_attr_capability.attr, |
| &dev_attr_stat.attr, |
| #ifdef CONFIG_FAIL_MAKE_REQUEST |
| &dev_attr_fail.attr, |
| #endif |
| NULL |
| }; |
| |
| static struct attribute_group disk_attr_group = { |
| .attrs = disk_attrs, |
| }; |
| |
| static struct attribute_group *disk_attr_groups[] = { |
| &disk_attr_group, |
| NULL |
| }; |
| |
| static void disk_release(struct device *dev) |
| { |
| struct gendisk *disk = dev_to_disk(dev); |
| |
| kfree(disk->random); |
| kfree(disk->part); |
| free_disk_stats(disk); |
| kfree(disk); |
| } |
| struct class block_class = { |
| .name = "block", |
| }; |
| |
| struct device_type disk_type = { |
| .name = "disk", |
| .groups = disk_attr_groups, |
| .release = disk_release, |
| }; |
| |
| /* |
| * aggregate disk stat collector. Uses the same stats that the sysfs |
| * entries do, above, but makes them available through one seq_file. |
| * |
| * The output looks suspiciously like /proc/partitions with a bunch of |
| * extra fields. |
| */ |
| |
| static void *diskstats_start(struct seq_file *part, loff_t *pos) |
| { |
| loff_t k = *pos; |
| struct device *dev; |
| |
| mutex_lock(&block_class_lock); |
| list_for_each_entry(dev, &block_class.devices, node) { |
| if (dev->type != &disk_type) |
| continue; |
| if (!k--) |
| return dev_to_disk(dev); |
| } |
| return NULL; |
| } |
| |
| static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos) |
| { |
| struct gendisk *gp = v; |
| struct device *dev; |
| |
| ++*pos; |
| list_for_each_entry(dev, &gp->dev.node, node) { |
| if (&dev->node == &block_class.devices) |
| return NULL; |
| if (dev->type == &disk_type) |
| return dev_to_disk(dev); |
| } |
| return NULL; |
| } |
| |
| static void diskstats_stop(struct seq_file *part, void *v) |
| { |
| mutex_unlock(&block_class_lock); |
| } |
| |
| static int diskstats_show(struct seq_file *s, void *v) |
| { |
| struct gendisk *gp = v; |
| char buf[BDEVNAME_SIZE]; |
| int n = 0; |
| |
| /* |
| if (&gp->dev.kobj.entry == block_class.devices.next) |
| seq_puts(s, "major minor name" |
| " rio rmerge rsect ruse wio wmerge " |
| "wsect wuse running use aveq" |
| "\n\n"); |
| */ |
| |
| preempt_disable(); |
| disk_round_stats(gp); |
| preempt_enable(); |
| seq_printf(s, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n", |
| gp->major, n + gp->first_minor, disk_name(gp, n, buf), |
| disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]), |
| (unsigned long long)disk_stat_read(gp, sectors[0]), |
| jiffies_to_msecs(disk_stat_read(gp, ticks[0])), |
| disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]), |
| (unsigned long long)disk_stat_read(gp, sectors[1]), |
| jiffies_to_msecs(disk_stat_read(gp, ticks[1])), |
| gp->in_flight, |
| jiffies_to_msecs(disk_stat_read(gp, io_ticks)), |
| jiffies_to_msecs(disk_stat_read(gp, time_in_queue))); |
| |
| /* now show all non-0 size partitions of it */ |
| for (n = 0; n < gp->minors - 1; n++) { |
| struct hd_struct *hd = gp->part[n]; |
| |
| if (hd && hd->nr_sects) |
| seq_printf(s, "%4d %4d %s %u %u %u %u\n", |
| gp->major, n + gp->first_minor + 1, |
| disk_name(gp, n + 1, buf), |
| hd->ios[0], hd->sectors[0], |
| hd->ios[1], hd->sectors[1]); |
| } |
| |
| return 0; |
| } |
| |
| struct seq_operations diskstats_op = { |
| .start = diskstats_start, |
| .next = diskstats_next, |
| .stop = diskstats_stop, |
| .show = diskstats_show |
| }; |
| |
| 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(&gd->dev.kobj, KOBJ_CHANGE, envp); |
| put_device(gd->driverfs_dev); |
| } |
| |
| 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); |
| |
| dev_t blk_lookup_devt(const char *name) |
| { |
| struct device *dev; |
| dev_t devt = MKDEV(0, 0); |
| |
| mutex_lock(&block_class_lock); |
| list_for_each_entry(dev, &block_class.devices, node) { |
| if (strcmp(dev->bus_id, name) == 0) { |
| devt = dev->devt; |
| break; |
| } |
| } |
| mutex_unlock(&block_class_lock); |
| |
| return devt; |
| } |
| |
| EXPORT_SYMBOL(blk_lookup_devt); |
| |
| struct gendisk *alloc_disk(int minors) |
| { |
| return alloc_disk_node(minors, -1); |
| } |
| |
| struct gendisk *alloc_disk_node(int minors, int node_id) |
| { |
| struct gendisk *disk; |
| |
| disk = kmalloc_node(sizeof(struct gendisk), |
| GFP_KERNEL | __GFP_ZERO, node_id); |
| if (disk) { |
| if (!init_disk_stats(disk)) { |
| kfree(disk); |
| return NULL; |
| } |
| if (minors > 1) { |
| int size = (minors - 1) * sizeof(struct hd_struct *); |
| disk->part = kmalloc_node(size, |
| GFP_KERNEL | __GFP_ZERO, node_id); |
| if (!disk->part) { |
| free_disk_stats(disk); |
| kfree(disk); |
| return NULL; |
| } |
| } |
| disk->minors = minors; |
| rand_initialize_disk(disk); |
| disk->dev.class = &block_class; |
| disk->dev.type = &disk_type; |
| device_initialize(&disk->dev); |
| INIT_WORK(&disk->async_notify, |
| media_change_notify_thread); |
| } |
| return disk; |
| } |
| |
| EXPORT_SYMBOL(alloc_disk); |
| EXPORT_SYMBOL(alloc_disk_node); |
| |
| struct kobject *get_disk(struct gendisk *disk) |
| { |
| struct module *owner; |
| struct kobject *kobj; |
| |
| if (!disk->fops) |
| return NULL; |
| owner = disk->fops->owner; |
| if (owner && !try_module_get(owner)) |
| return NULL; |
| kobj = kobject_get(&disk->dev.kobj); |
| if (kobj == NULL) { |
| module_put(owner); |
| return NULL; |
| } |
| return kobj; |
| |
| } |
| |
| EXPORT_SYMBOL(get_disk); |
| |
| void put_disk(struct gendisk *disk) |
| { |
| if (disk) |
| kobject_put(&disk->dev.kobj); |
| } |
| |
| EXPORT_SYMBOL(put_disk); |
| |
| void set_device_ro(struct block_device *bdev, int flag) |
| { |
| if (bdev->bd_contains != bdev) |
| bdev->bd_part->policy = flag; |
| else |
| bdev->bd_disk->policy = flag; |
| } |
| |
| EXPORT_SYMBOL(set_device_ro); |
| |
| void set_disk_ro(struct gendisk *disk, int flag) |
| { |
| int i; |
| disk->policy = flag; |
| for (i = 0; i < disk->minors - 1; i++) |
| if (disk->part[i]) disk->part[i]->policy = flag; |
| } |
| |
| EXPORT_SYMBOL(set_disk_ro); |
| |
| int bdev_read_only(struct block_device *bdev) |
| { |
| if (!bdev) |
| return 0; |
| else if (bdev->bd_contains != bdev) |
| return bdev->bd_part->policy; |
| else |
| return bdev->bd_disk->policy; |
| } |
| |
| EXPORT_SYMBOL(bdev_read_only); |
| |
| int invalidate_partition(struct gendisk *disk, int index) |
| { |
| int res = 0; |
| struct block_device *bdev = bdget_disk(disk, index); |
| if (bdev) { |
| fsync_bdev(bdev); |
| res = __invalidate_device(bdev); |
| bdput(bdev); |
| } |
| return res; |
| } |
| |
| EXPORT_SYMBOL(invalidate_partition); |