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- /*
- * 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>
- struct subsystem block_subsys;
- static DEFINE_MUTEX(block_subsys_lock);
- /*
- * 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_subsys_lock);
- for (dp = major_names[offset]; dp; dp = dp->next)
- seq_printf(f, "%3d %s\n", dp->major, dp->name);
- mutex_unlock(&block_subsys_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_subsys_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_subsys_lock);
- return ret;
- }
- EXPORT_SYMBOL(register_blkdev);
- /* todo: make void - error printk here */
- int 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);
- int ret = 0;
- mutex_lock(&block_subsys_lock);
- for (n = &major_names[index]; *n; n = &(*n)->next)
- if ((*n)->major == major)
- break;
- if (!*n || strcmp((*n)->name, name))
- ret = -EINVAL;
- else {
- p = *n;
- *n = p->next;
- }
- mutex_unlock(&block_subsys_lock);
- kfree(p);
- return ret;
- }
- 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 dev, unsigned long range, struct module *module,
- struct kobject *(*probe)(dev_t, int *, void *),
- int (*lock)(dev_t, void *), void *data)
- {
- kobj_map(bdev_map, dev, range, module, probe, lock, data);
- }
- EXPORT_SYMBOL(blk_register_region);
- void blk_unregister_region(dev_t dev, unsigned long range)
- {
- kobj_unmap(bdev_map, dev, range);
- }
- EXPORT_SYMBOL(blk_unregister_region);
- static struct kobject *exact_match(dev_t dev, int *part, void *data)
- {
- struct gendisk *p = data;
- return &p->kobj;
- }
- static int exact_lock(dev_t dev, 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);
- }
- #define to_disk(obj) container_of(obj,struct gendisk,kobj)
- /**
- * 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 dev, int *part)
- {
- struct kobject *kobj = kobj_lookup(bdev_map, dev, part);
- return kobj ? to_disk(kobj) : NULL;
- }
- #ifdef CONFIG_PROC_FS
- /* iterator */
- static void *part_start(struct seq_file *part, loff_t *pos)
- {
- struct list_head *p;
- loff_t l = *pos;
- mutex_lock(&block_subsys_lock);
- list_for_each(p, &block_subsys.kset.list)
- if (!l--)
- return list_entry(p, struct gendisk, kobj.entry);
- return NULL;
- }
- static void *part_next(struct seq_file *part, void *v, loff_t *pos)
- {
- struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
- ++*pos;
- return p==&block_subsys.kset.list ? NULL :
- list_entry(p, struct gendisk, kobj.entry);
- }
- static void part_stop(struct seq_file *part, void *v)
- {
- mutex_unlock(&block_subsys_lock);
- }
- static int show_partition(struct seq_file *part, void *v)
- {
- struct gendisk *sgp = v;
- int n;
- char buf[BDEVNAME_SIZE];
- if (&sgp->kobj.entry == block_subsys.kset.list.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 dev, int *part, void *data)
- {
- if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0)
- /* Make old-style 2.4 aliases work */
- request_module("block-major-%d", MAJOR(dev));
- return NULL;
- }
- static int __init genhd_device_init(void)
- {
- int err;
- bdev_map = kobj_map_init(base_probe, &block_subsys_lock);
- blk_dev_init();
- err = subsystem_register(&block_subsys);
- if (err < 0)
- printk(KERN_WARNING "%s: subsystem_register error: %d\n",
- __FUNCTION__, err);
- return err;
- }
- subsys_initcall(genhd_device_init);
- /*
- * kobject & sysfs bindings for block devices
- */
- static ssize_t disk_attr_show(struct kobject *kobj, struct attribute *attr,
- char *page)
- {
- struct gendisk *disk = to_disk(kobj);
- struct disk_attribute *disk_attr =
- container_of(attr,struct disk_attribute,attr);
- ssize_t ret = -EIO;
- if (disk_attr->show)
- ret = disk_attr->show(disk,page);
- return ret;
- }
- static ssize_t disk_attr_store(struct kobject * kobj, struct attribute * attr,
- const char *page, size_t count)
- {
- struct gendisk *disk = to_disk(kobj);
- struct disk_attribute *disk_attr =
- container_of(attr,struct disk_attribute,attr);
- ssize_t ret = 0;
- if (disk_attr->store)
- ret = disk_attr->store(disk, page, count);
- return ret;
- }
- static struct sysfs_ops disk_sysfs_ops = {
- .show = &disk_attr_show,
- .store = &disk_attr_store,
- };
- static ssize_t disk_uevent_store(struct gendisk * disk,
- const char *buf, size_t count)
- {
- kobject_uevent(&disk->kobj, KOBJ_ADD);
- return count;
- }
- static ssize_t disk_dev_read(struct gendisk * disk, char *page)
- {
- dev_t base = MKDEV(disk->major, disk->first_minor);
- return print_dev_t(page, base);
- }
- static ssize_t disk_range_read(struct gendisk * disk, char *page)
- {
- return sprintf(page, "%d\n", disk->minors);
- }
- static ssize_t disk_removable_read(struct gendisk * disk, char *page)
- {
- return sprintf(page, "%d\n",
- (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
- }
- static ssize_t disk_size_read(struct gendisk * disk, char *page)
- {
- return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk));
- }
- static ssize_t disk_stats_read(struct gendisk * disk, char *page)
- {
- preempt_disable();
- disk_round_stats(disk);
- preempt_enable();
- return sprintf(page,
- "%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)));
- }
- static struct disk_attribute disk_attr_uevent = {
- .attr = {.name = "uevent", .mode = S_IWUSR },
- .store = disk_uevent_store
- };
- static struct disk_attribute disk_attr_dev = {
- .attr = {.name = "dev", .mode = S_IRUGO },
- .show = disk_dev_read
- };
- static struct disk_attribute disk_attr_range = {
- .attr = {.name = "range", .mode = S_IRUGO },
- .show = disk_range_read
- };
- static struct disk_attribute disk_attr_removable = {
- .attr = {.name = "removable", .mode = S_IRUGO },
- .show = disk_removable_read
- };
- static struct disk_attribute disk_attr_size = {
- .attr = {.name = "size", .mode = S_IRUGO },
- .show = disk_size_read
- };
- static struct disk_attribute disk_attr_stat = {
- .attr = {.name = "stat", .mode = S_IRUGO },
- .show = disk_stats_read
- };
- #ifdef CONFIG_FAIL_MAKE_REQUEST
- static ssize_t disk_fail_store(struct gendisk * disk,
- const char *buf, size_t count)
- {
- 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;
- }
- static ssize_t disk_fail_read(struct gendisk * disk, char *page)
- {
- return sprintf(page, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
- }
- static struct disk_attribute disk_attr_fail = {
- .attr = {.name = "make-it-fail", .mode = S_IRUGO | S_IWUSR },
- .store = disk_fail_store,
- .show = disk_fail_read
- };
- #endif
- static struct attribute * default_attrs[] = {
- &disk_attr_uevent.attr,
- &disk_attr_dev.attr,
- &disk_attr_range.attr,
- &disk_attr_removable.attr,
- &disk_attr_size.attr,
- &disk_attr_stat.attr,
- #ifdef CONFIG_FAIL_MAKE_REQUEST
- &disk_attr_fail.attr,
- #endif
- NULL,
- };
- static void disk_release(struct kobject * kobj)
- {
- struct gendisk *disk = to_disk(kobj);
- kfree(disk->random);
- kfree(disk->part);
- free_disk_stats(disk);
- kfree(disk);
- }
- static struct kobj_type ktype_block = {
- .release = disk_release,
- .sysfs_ops = &disk_sysfs_ops,
- .default_attrs = default_attrs,
- };
- extern struct kobj_type ktype_part;
- static int block_uevent_filter(struct kset *kset, struct kobject *kobj)
- {
- struct kobj_type *ktype = get_ktype(kobj);
- return ((ktype == &ktype_block) || (ktype == &ktype_part));
- }
- static int block_uevent(struct kset *kset, struct kobject *kobj, char **envp,
- int num_envp, char *buffer, int buffer_size)
- {
- struct kobj_type *ktype = get_ktype(kobj);
- struct device *physdev;
- struct gendisk *disk;
- struct hd_struct *part;
- int length = 0;
- int i = 0;
- if (ktype == &ktype_block) {
- disk = container_of(kobj, struct gendisk, kobj);
- add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
- &length, "MINOR=%u", disk->first_minor);
- } else if (ktype == &ktype_part) {
- disk = container_of(kobj->parent, struct gendisk, kobj);
- part = container_of(kobj, struct hd_struct, kobj);
- add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
- &length, "MINOR=%u",
- disk->first_minor + part->partno);
- } else
- return 0;
- add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
- "MAJOR=%u", disk->major);
- /* add physical device, backing this device */
- physdev = disk->driverfs_dev;
- if (physdev) {
- char *path = kobject_get_path(&physdev->kobj, GFP_KERNEL);
- add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
- &length, "PHYSDEVPATH=%s", path);
- kfree(path);
- if (physdev->bus)
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVBUS=%s",
- physdev->bus->name);
- if (physdev->driver)
- add_uevent_var(envp, num_envp, &i,
- buffer, buffer_size, &length,
- "PHYSDEVDRIVER=%s",
- physdev->driver->name);
- }
- /* terminate, set to next free slot, shrink available space */
- envp[i] = NULL;
- envp = &envp[i];
- num_envp -= i;
- buffer = &buffer[length];
- buffer_size -= length;
- return 0;
- }
- static struct kset_uevent_ops block_uevent_ops = {
- .filter = block_uevent_filter,
- .uevent = block_uevent,
- };
- decl_subsys(block, &ktype_block, &block_uevent_ops);
- /*
- * aggregate disk stat collector. Uses the same stats that the sysfs
- * entries do, above, but makes them available through one seq_file.
- * Watching a few disks may be efficient through sysfs, but watching
- * all of them will be more efficient through this interface.
- *
- * The output looks suspiciously like /proc/partitions with a bunch of
- * extra fields.
- */
- /* iterator */
- static void *diskstats_start(struct seq_file *part, loff_t *pos)
- {
- loff_t k = *pos;
- struct list_head *p;
- mutex_lock(&block_subsys_lock);
- list_for_each(p, &block_subsys.kset.list)
- if (!k--)
- return list_entry(p, struct gendisk, kobj.entry);
- return NULL;
- }
- static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
- {
- struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
- ++*pos;
- return p==&block_subsys.kset.list ? NULL :
- list_entry(p, struct gendisk, kobj.entry);
- }
- static void diskstats_stop(struct seq_file *part, void *v)
- {
- mutex_unlock(&block_subsys_lock);
- }
- static int diskstats_show(struct seq_file *s, void *v)
- {
- struct gendisk *gp = v;
- char buf[BDEVNAME_SIZE];
- int n = 0;
- /*
- if (&sgp->kobj.entry == block_subsys.kset.list.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
- };
- 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, node_id);
- if (disk) {
- memset(disk, 0, sizeof(struct gendisk));
- 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, node_id);
- if (!disk->part) {
- kfree(disk);
- return NULL;
- }
- memset(disk->part, 0, size);
- }
- disk->minors = minors;
- kobj_set_kset_s(disk,block_subsys);
- kobject_init(&disk->kobj);
- rand_initialize_disk(disk);
- }
- 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->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->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);
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