openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity
linux/block/genhd.c

1140 lines
26 KiB
C
Raw Blame History

/*
* 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>
#include <linux/idr.h>
#include "blk.h"
static DEFINE_MUTEX(block_class_lock);
#ifndef CONFIG_SYSFS_DEPRECATED
struct kobject *block_depr;
#endif
/* for extended dynamic devt allocation, currently only one major is used */
#define MAX_EXT_DEVT (1 << MINORBITS)
/* For extended devt allocation. ext_devt_mutex prevents look up
* results from going away underneath its user.
*/
static DEFINE_MUTEX(ext_devt_mutex);
static DEFINE_IDR(ext_devt_idr);
static struct device_type disk_type;
/**
* disk_get_part - get partition
* @disk: disk to look partition from
* @partno: partition number
*
* Look for partition @partno from @disk. If found, increment
* reference count and return it.
*
* CONTEXT:
* Don't care.
*
* RETURNS:
* Pointer to the found partition on success, NULL if not found.
*/
struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
{
struct hd_struct *part;
if (unlikely(partno < 0 || partno >= disk_max_parts(disk)))
return NULL;
rcu_read_lock();
part = rcu_dereference(disk->__part[partno]);
if (part)
get_device(part_to_dev(part));
rcu_read_unlock();
return part;
}
EXPORT_SYMBOL_GPL(disk_get_part);
/**
* disk_part_iter_init - initialize partition iterator
* @piter: iterator to initialize
* @disk: disk to iterate over
* @flags: DISK_PITER_* flags
*
* Initialize @piter so that it iterates over partitions of @disk.
*
* CONTEXT:
* Don't care.
*/
void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
unsigned int flags)
{
piter->disk = disk;
piter->part = NULL;
if (flags & DISK_PITER_REVERSE)
piter->idx = disk_max_parts(piter->disk) - 1;
else if (flags & DISK_PITER_INCL_PART0)
piter->idx = 0;
else
piter->idx = 1;
piter->flags = flags;
}
EXPORT_SYMBOL_GPL(disk_part_iter_init);
/**
* disk_part_iter_next - proceed iterator to the next partition and return it
* @piter: iterator of interest
*
* Proceed @piter to the next partition and return it.
*
* CONTEXT:
* Don't care.
*/
struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
{
int inc, end;
/* put the last partition */
disk_put_part(piter->part);
piter->part = NULL;
rcu_read_lock();
/* determine iteration parameters */
if (piter->flags & DISK_PITER_REVERSE) {
inc = -1;
if (piter->flags & DISK_PITER_INCL_PART0)
end = -1;
else
end = 0;
} else {
inc = 1;
end = disk_max_parts(piter->disk);
}
/* iterate to the next partition */
for (; piter->idx != end; piter->idx += inc) {
struct hd_struct *part;
part = rcu_dereference(piter->disk->__part[piter->idx]);
if (!part)
continue;
if (!(piter->flags & DISK_PITER_INCL_EMPTY) && !part->nr_sects)
continue;
get_device(part_to_dev(part));
piter->part = part;
piter->idx += inc;
break;
}
rcu_read_unlock();
return piter->part;
}
EXPORT_SYMBOL_GPL(disk_part_iter_next);
/**
* disk_part_iter_exit - finish up partition iteration
* @piter: iter of interest
*
* Called when iteration is over. Cleans up @piter.
*
* CONTEXT:
* Don't care.
*/
void disk_part_iter_exit(struct disk_part_iter *piter)
{
disk_put_part(piter->part);
piter->part = NULL;
}
EXPORT_SYMBOL_GPL(disk_part_iter_exit);
/**
* disk_map_sector_rcu - map sector to partition
* @disk: gendisk of interest
* @sector: sector to map
*
* Find out which partition @sector maps to on @disk. This is
* primarily used for stats accounting.
*
* CONTEXT:
* RCU read locked. The returned partition pointer is valid only
* while preemption is disabled.
*
* RETURNS:
* Found partition on success, NULL if there's no matching partition.
*/
struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
{
int i;
for (i = 1; i < disk_max_parts(disk); i++) {
struct hd_struct *part = rcu_dereference(disk->__part[i]);
if (part && part->start_sect <= sector &&
sector < part->start_sect + part->nr_sects)
return part;
}
return NULL;
}
EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
/*
* 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 *seqf, 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(seqf, "%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;
/**
* 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 partition
* @part: partition to allocate dev_t for
* @gfp_mask: memory allocation flag
* @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 hd_struct *part, dev_t *devt)
{
struct gendisk *disk = part_to_disk(part);
int idx, rc;
/* in consecutive minor range? */
if (part->partno < disk->minors) {
*devt = MKDEV(disk->major, disk->first_minor + part->partno);
return 0;
}
/* allocate ext devt */
do {
if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL))
return -ENOMEM;
rc = idr_get_new(&ext_devt_idr, part, &idx);
} while (rc == -EAGAIN);
if (rc)
return rc;
if (idx > MAX_EXT_DEVT) {
idr_remove(&ext_devt_idr, idx);
return -EBUSY;
}
*devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
return 0;
}
/**
* 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)
{
might_sleep();
if (devt == MKDEV(0, 0))
return;
if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
mutex_lock(&ext_devt_mutex);
idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
mutex_unlock(&ext_devt_mutex);
}
}
static char *bdevt_str(dev_t devt, char *buf)
{
if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
char tbuf[BDEVT_SIZE];
snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
} else
snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
return buf;
}
/*
* 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 *partno, void *data)
{
struct gendisk *p = data;
return &disk_to_dev(p)->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)
{
struct backing_dev_info *bdi;
int retval;
disk->flags |= GENHD_FL_UP;
disk_to_dev(disk)->devt = MKDEV(disk->major, disk->first_minor);
blk_register_region(disk_devt(disk), disk->minors, NULL,
exact_match, exact_lock, disk);
register_disk(disk);
blk_register_queue(disk);
bdi = &disk->queue->backing_dev_info;
bdi_register_dev(bdi, disk_devt(disk));
retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
"bdi");
WARN_ON(retval);
}
EXPORT_SYMBOL(add_disk);
EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */
void unlink_gendisk(struct gendisk *disk)
{
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);
}
/**
* get_gendisk - get partitioning information for a given device
* @devt: device to get partitioning information for
* @part: returned partition index
*
* This function gets the structure containing partitioning
* information for the given device @devt.
*/
struct gendisk *get_gendisk(dev_t devt, int *partno)
{
struct gendisk *disk = NULL;
if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
struct kobject *kobj;
kobj = kobj_lookup(bdev_map, devt, partno);
if (kobj)
disk = dev_to_disk(kobj_to_dev(kobj));
} else {
struct hd_struct *part;
mutex_lock(&ext_devt_mutex);
part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
if (part && get_disk(part_to_disk(part))) {
*partno = part->partno;
disk = part_to_disk(part);
}
mutex_unlock(&ext_devt_mutex);
}
return disk;
}
/**
* 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.
*/
extern struct block_device *bdget_disk(struct gendisk *disk, int partno)
{
struct hd_struct *part;
struct block_device *bdev = NULL;
part = disk_get_part(disk, partno);
if (part && (part->nr_sects || partno == 0))
bdev = bdget(part_devt(part));
disk_put_part(part);
return bdev;
}
EXPORT_SYMBOL(bdget_disk);
/*
* 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 class_dev_iter iter;
struct device *dev;
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 disk_part_iter piter;
struct hd_struct *part;
char name_buf[BDEVNAME_SIZE];
char devt_buf[BDEVT_SIZE];
/*
* Don't show empty devices or things that have been
* surpressed
*/
if (get_capacity(disk) == 0 ||
(disk->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("%s %10llu %s",
bdevt_str(disk_devt(disk), devt_buf),
(unsigned long long)get_capacity(disk) >> 1,
disk_name(disk, 0, name_buf));
if (disk->driverfs_dev != NULL &&
disk->driverfs_dev->driver != NULL)
printk(" driver: %s\n",
disk->driverfs_dev->driver->name);
else
printk(" (driver?)\n");
/* now show the partitions */
disk_part_iter_init(&piter, disk, 0);
while ((part = disk_part_iter_next(&piter)))
printk(" %s %10llu %s\n",
bdevt_str(part_devt(part), devt_buf),
(unsigned long long)part->nr_sects >> 1,
disk_name(disk, part->partno, name_buf));
disk_part_iter_exit(&piter);
}
class_dev_iter_exit(&iter);
}
#ifdef CONFIG_PROC_FS
/* iterator */
static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
{
loff_t skip = *pos;
struct class_dev_iter *iter;
struct device *dev;
iter = kmalloc(GFP_KERNEL, sizeof(*iter));
if (!iter)
return ERR_PTR(-ENOMEM);
seqf->private = iter;
class_dev_iter_init(iter, &block_class, NULL, &disk_type);
do {
dev = class_dev_iter_next(iter);
if (!dev)
return NULL;
} while (skip--);
return dev_to_disk(dev);
}
static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
{
struct device *dev;
(*pos)++;
dev = class_dev_iter_next(seqf->private);
if (dev)
return dev_to_disk(dev);
return NULL;
}
static void disk_seqf_stop(struct seq_file *seqf, void *v)
{
struct class_dev_iter *iter = seqf->private;
/* stop is called even after start failed :-( */
if (iter) {
class_dev_iter_exit(iter);
kfree(iter);
}
}
static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
{
static void *p;
p = disk_seqf_start(seqf, pos);
if (!IS_ERR(p) && p)
seq_puts(seqf, "major minor #blocks name\n\n");
return p;
}
static int show_partition(struct seq_file *seqf, void *v)
{
struct gendisk *sgp = v;
struct disk_part_iter piter;
struct hd_struct *part;
char buf[BDEVNAME_SIZE];
/* Don't show non-partitionable removeable devices or empty devices */
if (!get_capacity(sgp) || (!disk_partitionable(sgp) &&
(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(seqf, "%4d %7d %10llu %s\n",
MAJOR(disk_devt(sgp)), MINOR(disk_devt(sgp)),
(unsigned long long)get_capacity(sgp) >> 1,
disk_name(sgp, 0, buf));
disk_part_iter_init(&piter, sgp, 0);
while ((part = disk_part_iter_next(&piter)))
seq_printf(seqf, "%4d %7d %10llu %s\n",
MAJOR(part_devt(part)), MINOR(part_devt(part)),
(unsigned long long)part->nr_sects >> 1,
disk_name(sgp, part->partno, buf));
disk_part_iter_exit(&piter);
return 0;
}
const struct seq_operations partitions_op = {
.start = show_partition_start,
.next = disk_seqf_next,
.stop = disk_seqf_stop,
.show = show_partition
};
#endif
static struct kobject *base_probe(dev_t devt, int *partno, 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)
{
int error;
block_class.dev_kobj = sysfs_dev_block_kobj;
error = class_register(&block_class);
if (unlikely(error))
return error;
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_ext_range_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct gendisk *disk = dev_to_disk(dev);
return sprintf(buf, "%d\n", disk_max_parts(disk));
}
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_ro_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct gendisk *disk = dev_to_disk(dev);
return sprintf(buf, "%d\n", disk->policy ? 1 : 0);
}
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);
int cpu;
cpu = disk_stat_lock();
disk_round_stats(cpu, disk);
disk_stat_unlock();
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(ext_range, S_IRUGO, disk_ext_range_show, NULL);
static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
static DEVICE_ATTR(size, S_IRUGO, part_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_ext_range.attr,
&dev_attr_removable.attr,
&dev_attr_ro.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",
};
static struct device_type disk_type = {
.name = "disk",
.groups = disk_attr_groups,
.release = disk_release,
};
#ifdef CONFIG_PROC_FS
/*
* 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 int diskstats_show(struct seq_file *seqf, void *v)
{
struct gendisk *gp = v;
struct disk_part_iter piter;
struct hd_struct *hd;
char buf[BDEVNAME_SIZE];
int cpu;
/*
if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
seq_puts(seqf, "major minor name"
" rio rmerge rsect ruse wio wmerge "
"wsect wuse running use aveq"
"\n\n");
*/
cpu = disk_stat_lock();
disk_round_stats(cpu, gp);
disk_stat_unlock();
seq_printf(seqf, "%4d %7d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
MAJOR(disk_devt(gp)), MINOR(disk_devt(gp)),
disk_name(gp, 0, 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 */
disk_part_iter_init(&piter, gp, 0);
while ((hd = disk_part_iter_next(&piter))) {
cpu = disk_stat_lock();
part_round_stats(cpu, hd);
disk_stat_unlock();
seq_printf(seqf, "%4d %7d %s %lu %lu %llu "
"%u %lu %lu %llu %u %u %u %u\n",
MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
disk_name(gp, hd->partno, buf),
part_stat_read(hd, ios[0]),
part_stat_read(hd, merges[0]),
(unsigned long long)part_stat_read(hd, sectors[0]),
jiffies_to_msecs(part_stat_read(hd, ticks[0])),
part_stat_read(hd, ios[1]),
part_stat_read(hd, merges[1]),
(unsigned long long)part_stat_read(hd, sectors[1]),
jiffies_to_msecs(part_stat_read(hd, ticks[1])),
hd->in_flight,
jiffies_to_msecs(part_stat_read(hd, io_ticks)),
jiffies_to_msecs(part_stat_read(hd, time_in_queue))
);
}
disk_part_iter_exit(&piter);
return 0;
}
const struct seq_operations diskstats_op = {
.start = disk_seqf_start,
.next = disk_seqf_next,
.stop = disk_seqf_stop,
.show = diskstats_show
};
#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);
struct class_dev_iter iter;
struct device *dev;
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 hd_struct *part;
if (strcmp(dev->bus_id, name))
continue;
part = disk_get_part(disk, partno);
if (part && (part->nr_sects || partno == 0)) {
devt = part_devt(part);
disk_put_part(part);
break;
}
disk_put_part(part);
}
class_dev_iter_exit(&iter);
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)
{
return alloc_disk_ext_node(minors, 0, node_id);
}
struct gendisk *alloc_disk_ext(int minors, int ext_minors)
{
return alloc_disk_ext_node(minors, ext_minors, -1);
}
struct gendisk *alloc_disk_ext_node(int minors, int ext_minors, int node_id)
{
struct gendisk *disk;
disk = kmalloc_node(sizeof(struct gendisk),
GFP_KERNEL | __GFP_ZERO, node_id);
if (disk) {
int tot_minors = minors + ext_minors;
int size = tot_minors * sizeof(struct hd_struct *);
if (!init_disk_stats(disk)) {
kfree(disk);
return NULL;
}
disk->__part = kmalloc_node(size, GFP_KERNEL | __GFP_ZERO,
node_id);
if (!disk->__part) {
free_disk_stats(disk);
kfree(disk);
return NULL;
}
disk->__part[0] = &disk->part0;
disk->minors = minors;
disk->ext_minors = ext_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));
INIT_WORK(&disk->async_notify,
media_change_notify_thread);
}
return disk;
}
EXPORT_SYMBOL(alloc_disk);
EXPORT_SYMBOL(alloc_disk_node);
EXPORT_SYMBOL(alloc_disk_ext);
EXPORT_SYMBOL(alloc_disk_ext_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_to_dev(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_to_dev(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)
{
struct disk_part_iter piter;
struct hd_struct *part;
disk->policy = flag;
disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
while ((part = disk_part_iter_next(&piter)))
part->policy = flag;
disk_part_iter_exit(&piter);
}
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 partno)
{
int res = 0;
struct block_device *bdev = bdget_disk(disk, partno);
if (bdev) {
fsync_bdev(bdev);
res = __invalidate_device(bdev);
bdput(bdev);
}
return res;
}
EXPORT_SYMBOL(invalidate_partition);
Reference in New Issue View Git Blame Copy Permalink