/*
md.c : Multiple Devices driver for Linux
Copyright (C) 1998, 1999, 2000 Ingo Molnar
completely rewritten, based on the MD driver code from Marc Zyngier
Changes:
- RAID-1/RAID-5 extensions by Miguel de Icaza, Gadi Oxman, Ingo Molnar
- RAID-6 extensions by H. Peter Anvin <hpa@zytor.com>
- boot support for linear and striped mode by Harald Hoyer <HarryH@Royal.Net>
- kerneld support by Boris Tobotras <boris@xtalk.msk.su>
- kmod support by: Cyrus Durgin
- RAID0 bugfixes: Mark Anthony Lisher <markal@iname.com>
- Devfs support by Richard Gooch <rgooch@atnf.csiro.au>
- lots of fixes and improvements to the RAID1/RAID5 and generic
RAID code (such as request based resynchronization):
Neil Brown <neilb@cse.unsw.edu.au>.
- persistent bitmap code
Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
You should have received a copy of the GNU General Public License
(for example /usr/src/linux/COPYING); if not, write to the Free
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/config.h>
#include <linux/kthread.h>
#include <linux/linkage.h>
#include <linux/raid/md.h>
#include <linux/raid/bitmap.h>
#include <linux/sysctl.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/buffer_head.h> /* for invalidate_bdev */
#include <linux/suspend.h>
#include <linux/init.h>
#include <linux/file.h>
#ifdef CONFIG_KMOD
#include <linux/kmod.h>
#endif
#include <asm/unaligned.h>
#define MAJOR_NR MD_MAJOR
#define MD_DRIVER
/* 63 partitions with the alternate major number (mdp) */
#define MdpMinorShift 6
#define DEBUG 0
#define dprintk(x...) ((void)(DEBUG && printk(x)))
#ifndef MODULE
static void autostart_arrays (int part);
#endif
static mdk_personality_t *pers[MAX_PERSONALITY];
static DEFINE_SPINLOCK(pers_lock);
/*
* Current RAID-1,4,5 parallel reconstruction 'guaranteed speed limit'
* is 1000 KB/sec, so the extra system load does not show up that much.
* Increase it if you want to have more _guaranteed_ speed. Note that
* the RAID driver will use the maximum available bandwidth if the IO
* subsystem is idle. There is also an 'absolute maximum' reconstruction
* speed limit - in case reconstruction slows down your system despite
* idle IO detection.
*
* you can change it via /proc/sys/dev/raid/speed_limit_min and _max.
*/
static int sysctl_speed_limit_min = 1000;
static int sysctl_speed_limit_max = 200000;
static struct ctl_table_header *raid_table_header;
static ctl_table raid_table[] = {
{
.ctl_name = DEV_RAID_SPEED_LIMIT_MIN,
.procname = "speed_limit_min",
.data = &sysctl_speed_limit_min,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = DEV_RAID_SPEED_LIMIT_MAX,
.procname = "speed_limit_max",
.data = &sysctl_speed_limit_max,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{ .ctl_name = 0 }
};
static ctl_table raid_dir_table[] = {
{
.ctl_name = DEV_RAID,
.procname = "raid",
.maxlen = 0,
.mode = 0555,
.child = raid_table,
},
{ .ctl_name = 0 }
};
static ctl_table raid_root_table[] = {
{
.ctl_name = CTL_DEV,
.procname = "dev",
.maxlen = 0,
.mode = 0555,
.child = raid_dir_table,
},
{ .ctl_name = 0 }
};
static struct block_device_operations md_fops;
/*
* Enables to iterate over all existing md arrays
* all_mddevs_lock protects this list.
*/
static LIST_HEAD(all_mddevs);
static DEFINE_SPINLOCK(all_mddevs_lock);
/*
* iterates through all used mddevs in the system.
* We take care to grab the all_mddevs_lock whenever navigating
* the list, and to always hold a refcount when unlocked.
* Any code which breaks out of this loop while own
* a reference to the current mddev and must mddev_put it.
*/
#define ITERATE_MDDEV(mddev,tmp) \
\
for (({ spin_lock(&all_mddevs_lock); \
tmp = all_mddevs.next; \
mddev = NULL;}); \
({ if (tmp != &all_mddevs) \
mddev_get(list_entry(tmp, mddev_t, all_mddevs));\
spin_unlock(&all_mddevs_lock); \
if (mddev) mddev_put(mddev); \
mddev = list_entry(tmp, mddev_t, all_mddevs); \
tmp != &all_mddevs;}); \
({ spin_lock(&all_mddevs_lock); \
tmp = tmp->next;}) \
)
static int md_fail_request (request_queue_t *q, struct bio *bio)
{
bio_io_error(bio, bio->bi_size);
return 0;
}
static inline mddev_t *mddev_get(mddev_t *mddev)
{
atomic_inc(&mddev->active);
return mddev;
}
static void mddev_put(mddev_t *mddev)
{
if (!atomic_dec_and_lock(&mddev->active, &all_mddevs_lock))
return;
if (!mddev->raid_disks && list_empty(&mddev->disks)) {
list_del(&mddev->all_mddevs);
blk_put_queue(mddev->queue);
kfree(mddev);
}
spin_unlock(&all_mddevs_lock);
}
static mddev_t * mddev_find(dev_t unit)
{
mddev_t *mddev, *new = NULL;
retry:
spin_lock(&all_mddevs_lock);
list_for_each_entry(mddev, &all_mddevs, all_mddevs)
if (mddev->unit == unit) {
mddev_get(mddev);
spin_unlock(&all_mddevs_lock);
kfree(new);
return mddev;
}
if (new) {
list_add(&new->all_mddevs, &all_mddevs);
spin_unlock(&all_mddevs_lock);
return new;
}
spin_unlock(&all_mddevs_lock);
new = (mddev_t *) kmalloc(sizeof(*new), GFP_KERNEL);
if (!new)
return NULL;
memset(new, 0, sizeof(*new));
new->unit = unit;
if (MAJOR(unit) == MD_MAJOR)
new->md_minor = MINOR(unit);
else
new->md_minor = MINOR(unit) >> MdpMinorShift;
init_MUTEX(&new->reconfig_sem);
INIT_LIST_HEAD(&new->disks);
INIT_LIST_HEAD(&new->all_mddevs);
init_timer(&new->safemode_timer);
atomic_set(&new->active, 1);
spin_lock_init(&new->write_lock);
init_waitqueue_head(&new->sb_wait);
new->queue = blk_alloc_queue(GFP_KERNEL);
if (!new->queue) {
kfree(new);
return NULL;
}
blk_queue_make_request(new->queue, md_fail_request);
goto retry;
}
static inline int mddev_lock(mddev_t * mddev)
{
return down_interruptible(&mddev->reconfig_sem);
}
static inline void mddev_lock_uninterruptible(mddev_t * mddev)
{
down(&mddev->reconfig_sem);
}
static inline int mddev_trylock(mddev_t * mddev)
{
return down_trylock(&mddev->reconfig_sem);
}
static inline void mddev_unlock(mddev_t * mddev)
{
up(&mddev->reconfig_sem);
md_wakeup_thread(mddev->thread);
}
mdk_rdev_t * find_rdev_nr(mddev_t *mddev, int nr)
{
mdk_rdev_t * rdev;
struct list_head *tmp;
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->desc_nr == nr)
return rdev;
}
return NULL;
}
static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->bdev->bd_dev == dev)
return rdev;
}
return NULL;
}
static inline sector_t calc_dev_sboffset(struct block_device *bdev)
{
sector_t size = bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
return MD_NEW_SIZE_BLOCKS(size);
}
static sector_t calc_dev_size(mdk_rdev_t *rdev, unsigned chunk_size)
{
sector_t size;
size = rdev->sb_offset;
if (chunk_size)
size &= ~((sector_t)chunk_size/1024 - 1);
return size;
}
static int alloc_disk_sb(mdk_rdev_t * rdev)
{
if (rdev->sb_page)
MD_BUG();
rdev->sb_page = alloc_page(GFP_KERNEL);
if (!rdev->sb_page) {
printk(KERN_ALERT "md: out of memory.\n");
return -EINVAL;
}
return 0;
}
static void free_disk_sb(mdk_rdev_t * rdev)
{
if (rdev->sb_page) {
page_cache_release(rdev->sb_page);
rdev->sb_loaded = 0;
rdev->sb_page = NULL;
rdev->sb_offset = 0;
rdev->size = 0;
}
}
static int super_written(struct bio *bio, unsigned int bytes_done, int error)
{
mdk_rdev_t *rdev = bio->bi_private;
if (bio->bi_size)
return 1;
if (error || !test_bit(BIO_UPTODATE, &bio->bi_flags))
md_error(rdev->mddev, rdev);
if (atomic_dec_and_test(&rdev->mddev->pending_writes))
wake_up(&rdev->mddev->sb_wait);
bio_put(bio);
return 0;
}
void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev,
sector_t sector, int size, struct page *page)
{
/* write first size bytes of page to sector of rdev
* Increment mddev->pending_writes before returning
* and decrement it on completion, waking up sb_wait
* if zero is reached.
* If an error occurred, call md_error
*/
struct bio *bio = bio_alloc(GFP_NOIO, 1);
bio->bi_bdev = rdev->bdev;
bio->bi_sector = sector;
bio_add_page(bio, page, size, 0);
bio->bi_private = rdev;
bio->bi_end_io = super_written;
atomic_inc(&mddev->pending_writes);
submit_bio((1<<BIO_RW)|(1<<BIO_RW_SYNC), bio);
}
static int bi_complete(struct bio *bio, unsigned int bytes_done, int error)
{
if (bio->bi_size)
return 1;
complete((struct completion*)bio->bi_private);
return 0;
}
int sync_page_io(struct block_device *bdev, sector_t sector, int size,
struct page *page, int rw)
{
struct bio *bio = bio_alloc(GFP_NOIO, 1);
struct completion event;
int ret;
rw |= (1 << BIO_RW_SYNC);
bio->bi_bdev = bdev;
bio->bi_sector = sector;
bio_add_page(bio, page, size, 0);
init_completion(&event);
bio->bi_private = &event;
bio->bi_end_io = bi_complete;
submit_bio(rw, bio);
wait_for_completion(&event);
ret = test_bit(BIO_UPTODATE, &bio->bi_flags);
bio_put(bio);
return ret;
}
static int read_disk_sb(mdk_rdev_t * rdev, int size)
{
char b[BDEVNAME_SIZE];
if (!rdev->sb_page) {
MD_BUG();
return -EINVAL;
}
if (rdev->sb_loaded)
return 0;
if (!sync_page_io(rdev->bdev, rdev->sb_offset<<1, size, rdev->sb_page, READ))
goto fail;
rdev->sb_loaded = 1;
return 0;
fail:
printk(KERN_WARNING "md: disabled device %s, could not read superblock.\n",
bdevname(rdev->bdev,b));
return -EINVAL;
}
static int uuid_equal(mdp_super_t *sb1, mdp_super_t *sb2)
{
if ( (sb1->set_uuid0 == sb2->set_uuid0) &&
(sb1->set_uuid1 == sb2->set_uuid1) &&
(sb1->set_uuid2 == sb2->set_uuid2) &&
(sb1->set_uuid3 == sb2->set_uuid3))
return 1;
return 0;
}
static int sb_equal(mdp_super_t *sb1, mdp_super_t *sb2)
{
int ret;
mdp_super_t *tmp1, *tmp2;
tmp1 = kmalloc(sizeof(*tmp1),GFP_KERNEL);
tmp2 = kmalloc(sizeof(*tmp2),GFP_KERNEL);
if (!tmp1 || !tmp2) {
ret = 0;
printk(KERN_INFO "md.c: sb1 is not equal to sb2!\n");
goto abort;
}
*tmp1 = *sb1;
*tmp2 = *sb2;
/*
* nr_disks is not constant
*/
tmp1->nr_disks = 0;
tmp2->nr_disks = 0;
if (memcmp(tmp1, tmp2, MD_SB_GENERIC_CONSTANT_WORDS * 4))
ret = 0;
else
ret = 1;
abort:
kfree(tmp1);
kfree(tmp2);
return ret;
}
static unsigned int calc_sb_csum(mdp_super_t * sb)
{
unsigned int disk_csum, csum;
disk_csum = sb->sb_csum;
sb->sb_csum = 0;
csum = csum_partial((void *)sb, MD_SB_BYTES, 0);
sb->sb_csum = disk_csum;
return csum;
}
/*
* Handle superblock details.
* We want to be able to handle multiple superblock formats
* so we have a common interface to them all, and an array of
* different handlers.
* We rely on user-space to write the initial superblock, and support
* reading and updating of superblocks.
* Interface methods are:
* int load_super(mdk_rdev_t *dev, mdk_rdev_t *refdev, int minor_version)
* loads and validates a superblock on dev.
* if refdev != NULL, compare superblocks on both devices
* Return:
* 0 - dev has a superblock that is compatible with refdev
* 1 - dev has a superblock that is compatible and newer than refdev
* so dev should be used as the refdev in future
* -EINVAL superblock incompatible or invalid
* -othererror e.g. -EIO
*
* int validate_super(mddev_t *mddev, mdk_rdev_t *dev)
* Verify that dev is acceptable into mddev.
* The first time, mddev->raid_disks will be 0, and data from
* dev should be merged in. Subsequent calls check that dev
* is new enough. Return 0 or -EINVAL
*
* void sync_super(mddev_t *mddev, mdk_rdev_t *dev)
* Update the superblock for rdev with data in mddev
* This does not write to disc.
*
*/
struct super_type {
char *name;
struct module *owner;
int (*load_super)(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version);
int (*validate_super)(mddev_t *mddev, mdk_rdev_t *rdev);
void (*sync_super)(mddev_t *mddev, mdk_rdev_t *rdev);
};
/*
* load_super for 0.90.0
*/
static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
{
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
mdp_super_t *sb;
int ret;
sector_t sb_offset;
/*
* Calculate the position of the superblock,
* it's at the end of the disk.
*
* It also happens to be a multiple of 4Kb.
*/
sb_offset = calc_dev_sboffset(rdev->bdev);
rdev->sb_offset = sb_offset;
ret = read_disk_sb(rdev, MD_SB_BYTES);
if (ret) return ret;
ret = -EINVAL;
bdevname(rdev->bdev, b);
sb = (mdp_super_t*)page_address(rdev->sb_page);
if (sb->md_magic != MD_SB_MAGIC) {
printk(KERN_ERR "md: invalid raid superblock magic on %s\n",
b);
goto abort;
}
if (sb->major_version != 0 ||
sb->minor_version != 90) {
printk(KERN_WARNING "Bad version number %d.%d on %s\n",
sb->major_version, sb->minor_version,
b);
goto abort;
}
if (sb->raid_disks <= 0)
goto abort;
if (csum_fold(calc_sb_csum(sb)) != csum_fold(sb->sb_csum)) {
printk(KERN_WARNING "md: invalid superblock checksum on %s\n",
b);
goto abort;
}
rdev->preferred_minor = sb->md_minor;
rdev->data_offset = 0;
rdev->sb_size = MD_SB_BYTES;
if (sb->level == LEVEL_MULTIPATH)
rdev->desc_nr = -1;
else
rdev->desc_nr = sb->this_disk.number;
if (refdev == 0)
ret = 1;
else {
__u64 ev1, ev2;
mdp_super_t *refsb = (mdp_super_t*)page_address(refdev->sb_page);
if (!uuid_equal(refsb, sb)) {
printk(KERN_WARNING "md: %s has different UUID to %s\n",
b, bdevname(refdev->bdev,b2));
goto abort;
}
if (!sb_equal(refsb, sb)) {
printk(KERN_WARNING "md: %s has same UUID"
" but different superblock to %s\n",
b, bdevname(refdev->bdev, b2));
goto abort;
}
ev1 = md_event(sb);
ev2 = md_event(refsb);
if (ev1 > ev2)
ret = 1;
else
ret = 0;
}
rdev->size = calc_dev_size(rdev, sb->chunk_size);
abort:
return ret;
}
/*
* validate_super for 0.90.0
*/
static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
{
mdp_disk_t *desc;
mdp_super_t *sb = (mdp_super_t *)page_address(rdev->sb_page);
rdev->raid_disk = -1;
rdev->in_sync = 0;
if (mddev->raid_disks == 0) {
mddev->major_version = 0;
mddev->minor_version = sb->minor_version;
mddev->patch_version = sb->patch_version;
mddev->persistent = ! sb->not_persistent;
mddev->chunk_size = sb->chunk_size;
mddev->ctime = sb->ctime;
mddev->utime = sb->utime;
mddev->level = sb->level;
mddev->layout = sb->layout;
mddev->raid_disks = sb->raid_disks;
mddev->size = sb->size;
mddev->events = md_event(sb);
mddev->bitmap_offset = 0;
mddev->default_bitmap_offset = MD_SB_BYTES >> 9;
if (sb->state & (1<<MD_SB_CLEAN))
mddev->recovery_cp = MaxSector;
else {
if (sb->events_hi == sb->cp_events_hi &&
sb->events_lo == sb->cp_events_lo) {
mddev->recovery_cp = sb->recovery_cp;
} else
mddev->recovery_cp = 0;
}
memcpy(mddev->uuid+0, &sb->set_uuid0, 4);
memcpy(mddev->uuid+4, &sb->set_uuid1, 4);
memcpy(mddev->uuid+8, &sb->set_uuid2, 4);
memcpy(mddev->uuid+12,&sb->set_uuid3, 4);
mddev->max_disks = MD_SB_DISKS;
if (sb->state & (1<<MD_SB_BITMAP_PRESENT) &&
mddev->bitmap_file == NULL) {
if (mddev->level != 1 && mddev->level != 5 && mddev->level != 6) {
/* FIXME use a better test */
printk(KERN_WARNING "md: bitmaps only support for raid1\n");
return -EINVAL;
}
mddev->bitmap_offset = mddev->default_bitmap_offset;
}
} else if (mddev->pers == NULL) {
/* Insist on good event counter while assembling */
__u64 ev1 = md_event(sb);
++ev1;
if (ev1 < mddev->events)
return -EINVAL;
} else if (mddev->bitmap) {
/* if adding to array with a bitmap, then we can accept an
* older device ... but not too old.
*/
__u64 ev1 = md_event(sb);
if (ev1 < mddev->bitmap->events_cleared)
return 0;
} else /* just a hot-add of a new device, leave raid_disk at -1 */
return 0;
if (mddev->level != LEVEL_MULTIPATH) {
rdev->faulty = 0;
rdev->flags = 0;
desc = sb->disks + rdev->desc_nr;
if (desc->state & (1<<MD_DISK_FAULTY))
rdev->faulty = 1;
else if (desc->state & (1<<MD_DISK_SYNC) &&
desc->raid_disk < mddev->raid_disks) {
rdev->in_sync = 1;
rdev->raid_disk = desc->raid_disk;
}
if (desc->state & (1<<MD_DISK_WRITEMOSTLY))
set_bit(WriteMostly, &rdev->flags);
} else /* MULTIPATH are always insync */
rdev->in_sync = 1;
return 0;
}
/*
* sync_super for 0.90.0
*/
static void super_90_sync(mddev_t *mddev, mdk_rdev_t *rdev)
{
mdp_super_t *sb;
struct list_head *tmp;
mdk_rdev_t *rdev2;
int next_spare = mddev->raid_disks;
/* make rdev->sb match mddev data..
*
* 1/ zero out disks
* 2/ Add info for each disk, keeping track of highest desc_nr (next_spare);
* 3/ any empty disks < next_spare become removed
*
* disks[0] gets initialised to REMOVED because
* we cannot be sure from other fields if it has
* been initialised or not.
*/
int i;
int active=0, working=0,failed=0,spare=0,nr_disks=0;
rdev->sb_size = MD_SB_BYTES;
sb = (mdp_super_t*)page_address(rdev->sb_page);
memset(sb, 0, sizeof(*sb));
sb->md_magic = MD_SB_MAGIC;
sb->major_version = mddev->major_version;
sb->minor_version = mddev->minor_version;
sb->patch_version = mddev->patch_version;
sb->gvalid_words = 0; /* ignored */
memcpy(&sb->set_uuid0, mddev->uuid+0, 4);
memcpy(&sb->set_uuid1, mddev->uuid+4, 4);
memcpy(&sb->set_uuid2, mddev->uuid+8, 4);
memcpy(&sb->set_uuid3, mddev->uuid+12,4);
sb->ctime = mddev->ctime;
sb->level = mddev->level;
sb->size = mddev->size;
sb->raid_disks = mddev->raid_disks;
sb->md_minor = mddev->md_minor;
sb->not_persistent = !mddev->persistent;
sb->utime = mddev->utime;
sb->state = 0;
sb->events_hi = (mddev->events>>32);
sb->events_lo = (u32)mddev->events;
if (mddev->in_sync)
{
sb->recovery_cp = mddev->recovery_cp;
sb->cp_events_hi = (mddev->events>>32);
sb->cp_events_lo = (u32)mddev->events;
if (mddev->recovery_cp == MaxSector)
sb->state = (1<< MD_SB_CLEAN);
} else
sb->recovery_cp = 0;
sb->layout = mddev->layout;
sb->chunk_size = mddev->chunk_size;
if (mddev->bitmap && mddev->bitmap_file == NULL)
sb->state |= (1<<MD_SB_BITMAP_PRESENT);
sb->disks[0].state = (1<<MD_DISK_REMOVED);
ITERATE_RDEV(mddev,rdev2,tmp) {
mdp_disk_t *d;
if (rdev2->raid_disk >= 0 && rdev2->in_sync && !rdev2->faulty)
rdev2->desc_nr = rdev2->raid_disk;
else
rdev2->desc_nr = next_spare++;
d = &sb->disks[rdev2->desc_nr];
nr_disks++;
d->number = rdev2->desc_nr;
d->major = MAJOR(rdev2->bdev->bd_dev);
d->minor = MINOR(rdev2->bdev->bd_dev);
if (rdev2->raid_disk >= 0 && rdev->in_sync && !rdev2->faulty)
d->raid_disk = rdev2->raid_disk;
else
d->raid_disk = rdev2->desc_nr; /* compatibility */
if (rdev2->faulty) {
d->state = (1<<MD_DISK_FAULTY);
failed++;
} else if (rdev2->in_sync) {
d->state = (1<<MD_DISK_ACTIVE);
d->state |= (1<<MD_DISK_SYNC);
active++;
working++;
} else {
d->state = 0;
spare++;
working++;
}
if (test_bit(WriteMostly, &rdev2->flags))
d->state |= (1<<MD_DISK_WRITEMOSTLY);
}
/* now set the "removed" and "faulty" bits on any missing devices */
for (i=0 ; i < mddev->raid_disks ; i++) {
mdp_disk_t *d = &sb->disks[i];
if (d->state == 0 && d->number == 0) {
d->number = i;
d->raid_disk = i;
d->state = (1<<MD_DISK_REMOVED);
d->state |= (1<<MD_DISK_FAULTY);
failed++;
}
}
sb->nr_disks = nr_disks;
sb->active_disks = active;
sb->working_disks = working;
sb->failed_disks = failed;
sb->spare_disks = spare;
sb->this_disk = sb->disks[rdev->desc_nr];
sb->sb_csum = calc_sb_csum(sb);
}
/*
* version 1 superblock
*/
static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
{
unsigned int disk_csum, csum;
unsigned long long newcsum;
int size = 256 + le32_to_cpu(sb->max_dev)*2;
unsigned int *isuper = (unsigned int*)sb;
int i;
disk_csum = sb->sb_csum;
sb->sb_csum = 0;
newcsum = 0;
for (i=0; size>=4; size -= 4 )
newcsum += le32_to_cpu(*isuper++);
if (size == 2)
newcsum += le16_to_cpu(*(unsigned short*) isuper);
csum = (newcsum & 0xffffffff) + (newcsum >> 32);
sb->sb_csum = disk_csum;
return cpu_to_le32(csum);
}
static int super_1_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version)
{
struct mdp_superblock_1 *sb;
int ret;
sector_t sb_offset;
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
int bmask;
/*
* Calculate the position of the superblock.
* It is always aligned to a 4K boundary and
* depeding on minor_version, it can be:
* 0: At least 8K, but less than 12K, from end of device
* 1: At start of device
* 2: 4K from start of device.
*/
switch(minor_version) {
case 0:
sb_offset = rdev->bdev->bd_inode->i_size >> 9;
sb_offset -= 8*2;
sb_offset &= ~(sector_t)(4*2-1);
/* convert from sectors to K */
sb_offset /= 2;
break;
case 1:
sb_offset = 0;
break;
case 2:
sb_offset = 4;
break;
default:
return -EINVAL;
}
rdev->sb_offset = sb_offset;
/* superblock is rarely larger than 1K, but it can be larger,
* and it is safe to read 4k, so we do that
*/
ret = read_disk_sb(rdev, 4096);
if (ret) return ret;
sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
if (sb->magic != cpu_to_le32(MD_SB_MAGIC) ||
sb->major_version != cpu_to_le32(1) ||
le32_to_cpu(sb->max_dev) > (4096-256)/2 ||
le64_to_cpu(sb->super_offset) != (rdev->sb_offset<<1) ||
(le32_to_cpu(sb->feature_map) & ~MD_FEATURE_ALL) != 0)
return -EINVAL;
if (calc_sb_1_csum(sb) != sb->sb_csum) {
printk("md: invalid superblock checksum on %s\n",
bdevname(rdev->bdev,b));
return -EINVAL;
}
if (le64_to_cpu(sb->data_size) < 10) {
printk("md: data_size too small on %s\n",
bdevname(rdev->bdev,b));
return -EINVAL;
}
rdev->preferred_minor = 0xffff;
rdev->data_offset = le64_to_cpu(sb->data_offset);
rdev->sb_size = le32_to_cpu(sb->max_dev) * 2 + 256;
bmask = queue_hardsect_size(rdev->bdev->bd_disk->queue)-1;
if (rdev->sb_size & bmask)
rdev-> sb_size = (rdev->sb_size | bmask)+1;
if (refdev == 0)
return 1;
else {
__u64 ev1, ev2;
struct mdp_superblock_1 *refsb =
(struct mdp_superblock_1*)page_address(refdev->sb_page);
if (memcmp(sb->set_uuid, refsb->set_uuid, 16) != 0 ||
sb->level != refsb->level ||
sb->layout != refsb->layout ||
sb->chunksize != refsb->chunksize) {
printk(KERN_WARNING "md: %s has strangely different"
" superblock to %s\n",
bdevname(rdev->bdev,b),
bdevname(refdev->bdev,b2));
return -EINVAL;
}
ev1 = le64_to_cpu(sb->events);
ev2 = le64_to_cpu(refsb->events);
if (ev1 > ev2)
return 1;
}
if (minor_version)
rdev->size = ((rdev->bdev->bd_inode->i_size>>9) - le64_to_cpu(sb->data_offset)) / 2;
else
rdev->size = rdev->sb_offset;
if (rdev->size < le64_to_cpu(sb->data_size)/2)
return -EINVAL;
rdev->size = le64_to_cpu(sb->data_size)/2;
if (le32_to_cpu(sb->chunksize))
rdev->size &= ~((sector_t)le32_to_cpu(sb->chunksize)/2 - 1);
return 0;
}
static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev)
{
struct mdp_superblock_1 *sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
rdev->raid_disk = -1;
rdev->in_sync = 0;
if (mddev->raid_disks == 0) {
mddev->major_version = 1;
mddev->patch_version = 0;
mddev->persistent = 1;
mddev->chunk_size = le32_to_cpu(sb->chunksize) << 9;
mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);
mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);
mddev->level = le32_to_cpu(sb->level);
mddev->layout = le32_to_cpu(sb->layout);
mddev->raid_disks = le32_to_cpu(sb->raid_disks);
mddev->size = le64_to_cpu(sb->size)/2;
mddev->events = le64_to_cpu(sb->events);
mddev->bitmap_offset = 0;
mddev->default_bitmap_offset = 0;
mddev->default_bitmap_offset = 1024;
mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
memcpy(mddev->uuid, sb->set_uuid, 16);
mddev->max_disks = (4096-256)/2;
if ((le32_to_cpu(sb->feature_map) & MD_FEATURE_BITMAP_OFFSET) &&
mddev->bitmap_file == NULL ) {
if (mddev->level != 1) {
printk(KERN_WARNING "md: bitmaps only supported for raid1\n");
return -EINVAL;
}
mddev->bitmap_offset = (__s32)le32_to_cpu(sb->bitmap_offset);
}
} else if (mddev->pers == NULL) {
/* Insist of good event counter while assembling */
__u64 ev1 = le64_to_cpu(sb->events);
++ev1;
if (ev1 < mddev->events)
return -EINVAL;
} else if (mddev->bitmap) {
/* If adding to array with a bitmap, then we can accept an
* older device, but not too old.
*/
__u64 ev1 = le64_to_cpu(sb->events);
if (ev1 < mddev->bitmap->events_cleared)
return 0;
} else /* just a hot-add of a new device, leave raid_disk at -1 */
return 0;
if (mddev->level != LEVEL_MULTIPATH) {
int role;
rdev->desc_nr = le32_to_cpu(sb->dev_number);
role = le16_to_cpu(sb->dev_roles[rdev->desc_nr]);
switch(role) {
case 0xffff: /* spare */
rdev->faulty = 0;
break;
case 0xfffe: /* faulty */
rdev->faulty = 1;
break;
default:
rdev->in_sync = 1;
rdev->faulty = 0;
rdev->raid_disk = role;
break;
}
rdev->flags = 0;
if (sb->devflags & WriteMostly1)
set_bit(WriteMostly, &rdev->flags);
} else /* MULTIPATH are always insync */
rdev->in_sync = 1;
return 0;
}
static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
{
struct mdp_superblock_1 *sb;
struct list_head *tmp;
mdk_rdev_t *rdev2;
int max_dev, i;
/* make rdev->sb match mddev and rdev data. */
sb = (struct mdp_superblock_1*)page_address(rdev->sb_page);
sb->feature_map = 0;
sb->pad0 = 0;
memset(sb->pad1, 0, sizeof(sb->pad1));
memset(sb->pad2, 0, sizeof(sb->pad2));
memset(sb->pad3, 0, sizeof(sb->pad3));
sb->utime = cpu_to_le64((__u64)mddev->utime);
sb->events = cpu_to_le64(mddev->events);
if (mddev->in_sync)
sb->resync_offset = cpu_to_le64(mddev->recovery_cp);
else
sb->resync_offset = cpu_to_le64(0);
if (mddev->bitmap && mddev->bitmap_file == NULL) {
sb->bitmap_offset = cpu_to_le32((__u32)mddev->bitmap_offset);
sb->feature_map = cpu_to_le32(MD_FEATURE_BITMAP_OFFSET);
}
max_dev = 0;
ITERATE_RDEV(mddev,rdev2,tmp)
if (rdev2->desc_nr+1 > max_dev)
max_dev = rdev2->desc_nr+1;
sb->max_dev = cpu_to_le32(max_dev);
for (i=0; i<max_dev;i++)
sb->dev_roles[i] = cpu_to_le16(0xfffe);
ITERATE_RDEV(mddev,rdev2,tmp) {
i = rdev2->desc_nr;
if (rdev2->faulty)
sb->dev_roles[i] = cpu_to_le16(0xfffe);
else if (rdev2->in_sync)
sb->dev_roles[i] = cpu_to_le16(rdev2->raid_disk);
else
sb->dev_roles[i] = cpu_to_le16(0xffff);
}
sb->recovery_offset = cpu_to_le64(0); /* not supported yet */
sb->sb_csum = calc_sb_1_csum(sb);
}
static struct super_type super_types[] = {
[0] = {
.name = "0.90.0",
.owner = THIS_MODULE,
.load_super = super_90_load,
.validate_super = super_90_validate,
.sync_super = super_90_sync,
},
[1] = {
.name = "md-1",
.owner = THIS_MODULE,
.load_super = super_1_load,
.validate_super = super_1_validate,
.sync_super = super_1_sync,
},
};
static mdk_rdev_t * match_dev_unit(mddev_t *mddev, mdk_rdev_t *dev)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev,rdev,tmp)
if (rdev->bdev->bd_contains == dev->bdev->bd_contains)
return rdev;
return NULL;
}
static int match_mddev_units(mddev_t *mddev1, mddev_t *mddev2)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev1,rdev,tmp)
if (match_dev_unit(mddev2, rdev))
return 1;
return 0;
}
static LIST_HEAD(pending_raid_disks);
static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
{
mdk_rdev_t *same_pdev;
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
if (rdev->mddev) {
MD_BUG();
return -EINVAL;
}
same_pdev = match_dev_unit(mddev, rdev);
if (same_pdev)
printk(KERN_WARNING
"%s: WARNING: %s appears to be on the same physical"
" disk as %s. True\n protection against single-disk"
" failure might be compromised.\n",
mdname(mddev), bdevname(rdev->bdev,b),
bdevname(same_pdev->bdev,b2));
/* Verify rdev->desc_nr is unique.
* If it is -1, assign a free number, else
* check number is not in use
*/
if (rdev->desc_nr < 0) {
int choice = 0;
if (mddev->pers) choice = mddev->raid_disks;
while (find_rdev_nr(mddev, choice))
choice++;
rdev->desc_nr = choice;
} else {
if (find_rdev_nr(mddev, rdev->desc_nr))
return -EBUSY;
}
list_add(&rdev->same_set, &mddev->disks);
rdev->mddev = mddev;
printk(KERN_INFO "md: bind<%s>\n", bdevname(rdev->bdev,b));
return 0;
}
static void unbind_rdev_from_array(mdk_rdev_t * rdev)
{
char b[BDEVNAME_SIZE];
if (!rdev->mddev) {
MD_BUG();
return;
}
list_del_init(&rdev->same_set);
printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
rdev->mddev = NULL;
}
/*
* prevent the device from being mounted, repartitioned or
* otherwise reused by a RAID array (or any other kernel
* subsystem), by bd_claiming the device.
*/
static int lock_rdev(mdk_rdev_t *rdev, dev_t dev)
{
int err = 0;
struct block_device *bdev;
char b[BDEVNAME_SIZE];
bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
if (IS_ERR(bdev)) {
printk(KERN_ERR "md: could not open %s.\n",
__bdevname(dev, b));
return PTR_ERR(bdev);
}
err = bd_claim(bdev, rdev);
if (err) {
printk(KERN_ERR "md: could not bd_claim %s.\n",
bdevname(bdev, b));
blkdev_put(bdev);
return err;
}
rdev->bdev = bdev;
return err;
}
static void unlock_rdev(mdk_rdev_t *rdev)
{
struct block_device *bdev = rdev->bdev;
rdev->bdev = NULL;
if (!bdev)
MD_BUG();
bd_release(bdev);
blkdev_put(bdev);
}
void md_autodetect_dev(dev_t dev);
static void export_rdev(mdk_rdev_t * rdev)
{
char b[BDEVNAME_SIZE];
printk(KERN_INFO "md: export_rdev(%s)\n",
bdevname(rdev->bdev,b));
if (rdev->mddev)
MD_BUG();
free_disk_sb(rdev);
list_del_init(&rdev->same_set);
#ifndef MODULE
md_autodetect_dev(rdev->bdev->bd_dev);
#endif
unlock_rdev(rdev);
kfree(rdev);
}
static void kick_rdev_from_array(mdk_rdev_t * rdev)
{
unbind_rdev_from_array(rdev);
export_rdev(rdev);
}
static void export_array(mddev_t *mddev)
{
struct list_head *tmp;
mdk_rdev_t *rdev;
ITERATE_RDEV(mddev,rdev,tmp) {
if (!rdev->mddev) {
MD_BUG();
continue;
}
kick_rdev_from_array(rdev);
}
if (!list_empty(&mddev->disks))
MD_BUG();
mddev->raid_disks = 0;
mddev->major_version = 0;
}
static void print_desc(mdp_disk_t *desc)
{
printk(" DISK<N:%d,(%d,%d),R:%d,S:%d>\n", desc->number,
desc->major,desc->minor,desc->raid_disk,desc->state);
}
static void print_sb(mdp_super_t *sb)
{
int i;
printk(KERN_INFO
"md: SB: (V:%d.%d.%d) ID:<%08x.%08x.%08x.%08x> CT:%08x\n",
sb->major_version, sb->minor_version, sb->patch_version,
sb->set_uuid0, sb->set_uuid1, sb->set_uuid2, sb->set_uuid3,
sb->ctime);
printk(KERN_INFO "md: L%d S%08d ND:%d RD:%d md%d LO:%d CS:%d\n",
sb->level, sb->size, sb->nr_disks, sb->raid_disks,
sb->md_minor, sb->layout, sb->chunk_size);
printk(KERN_INFO "md: UT:%08x ST:%d AD:%d WD:%d"
" FD:%d SD:%d CSUM:%08x E:%08lx\n",
sb->utime, sb->state, sb->active_disks, sb->working_disks,
sb->failed_disks, sb->spare_disks,
sb->sb_csum, (unsigned long)sb->events_lo);
printk(KERN_INFO);
for (i = 0; i < MD_SB_DISKS; i++) {
mdp_disk_t *desc;
desc = sb->disks + i;
if (desc->number || desc->major || desc->minor ||
desc->raid_disk || (desc->state && (desc->state != 4))) {
printk(" D %2d: ", i);
print_desc(desc);
}
}
printk(KERN_INFO "md: THIS: ");
print_desc(&sb->this_disk);
}
static void print_rdev(mdk_rdev_t *rdev)
{
char b[BDEVNAME_SIZE];
printk(KERN_INFO "md: rdev %s, SZ:%08llu F:%d S:%d DN:%u\n",
bdevname(rdev->bdev,b), (unsigned long long)rdev->size,
rdev->faulty, rdev->in_sync, rdev->desc_nr);
if (rdev->sb_loaded) {
printk(KERN_INFO "md: rdev superblock:\n");
print_sb((mdp_super_t*)page_address(rdev->sb_page));
} else
printk(KERN_INFO "md: no rdev superblock!\n");
}
void md_print_devices(void)
{
struct list_head *tmp, *tmp2;
mdk_rdev_t *rdev;
mddev_t *mddev;
char b[BDEVNAME_SIZE];
printk("\n");
printk("md: **********************************\n");
printk("md: * <COMPLETE RAID STATE PRINTOUT> *\n");
printk("md: **********************************\n");
ITERATE_MDDEV(mddev,tmp) {
if (mddev->bitmap)
bitmap_print_sb(mddev->bitmap);
else
printk("%s: ", mdname(mddev));
ITERATE_RDEV(mddev,rdev,tmp2)
printk("<%s>", bdevname(rdev->bdev,b));
printk("\n");
ITERATE_RDEV(mddev,rdev,tmp2)
print_rdev(rdev);
}
printk("md: **********************************\n");
printk("\n");
}
static void sync_sbs(mddev_t * mddev)
{
mdk_rdev_t *rdev;
struct list_head *tmp;
ITERATE_RDEV(mddev,rdev,tmp) {
super_types[mddev->major_version].
sync_super(mddev, rdev);
rdev->sb_loaded = 1;
}
}
static void md_update_sb(mddev_t * mddev)
{
int err;
struct list_head *tmp;
mdk_rdev_t *rdev;
int sync_req;
repeat:
spin_lock(&mddev->write_lock);
sync_req = mddev->in_sync;
mddev->utime = get_seconds();
mddev->events ++;
if (!mddev->events) {
/*
* oops, this 64-bit counter should never wrap.
* Either we are in around ~1 trillion A.C., assuming
* 1 reboot per second, or we have a bug:
*/
MD_BUG();
mddev->events --;
}
mddev->sb_dirty = 2;
sync_sbs(mddev);
/*
* do not write anything to disk if using
* nonpersistent superblocks
*/
if (!mddev->persistent) {
mddev->sb_dirty = 0;
spin_unlock(&mddev->write_lock);
wake_up(&mddev->sb_wait);
return;
}
spin_unlock(&mddev->write_lock);
dprintk(KERN_INFO
"md: updating %s RAID superblock on device (in sync %d)\n",
mdname(mddev),mddev->in_sync);
err = bitmap_update_sb(mddev->bitmap);
ITERATE_RDEV(mddev,rdev,tmp) {
char b[BDEVNAME_SIZE];
dprintk(KERN_INFO "md: ");
if (rdev->faulty)
dprintk("(skipping faulty ");
dprintk("%s ", bdevname(rdev->bdev,b));
if (!rdev->faulty) {
md_super_write(mddev,rdev,
rdev->sb_offset<<1, rdev->sb_size,
rdev->sb_page);
dprintk(KERN_INFO "(write) %s's sb offset: %llu\n",
bdevname(rdev->bdev,b),
(unsigned long long)rdev->sb_offset);
} else
dprintk(")\n");
if (mddev->level == LEVEL_MULTIPATH)
/* only need to write one superblock... */
break;
}
wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
/* if there was a failure, sb_dirty was set to 1, and we re-write super */
spin_lock(&mddev->write_lock);
if (mddev->in_sync != sync_req|| mddev->sb_dirty == 1) {
/* have to write it out again */
spin_unlock(&mddev->write_lock);
goto repeat;
}
mddev->sb_dirty = 0;
spin_unlock(&mddev->write_lock);
wake_up(&mddev->sb_wait);
}
/*
* Import a device. If 'super_format' >= 0, then sanity check the superblock
*
* mark the device faulty if:
*
* - the device is nonexistent (zero size)
* - the device has no valid superblock
*
* a faulty rdev _never_ has rdev->sb set.
*/
static mdk_rdev_t *md_import_device(dev_t newdev, int super_format, int super_minor)
{
char b[BDEVNAME_SIZE];
int err;
mdk_rdev_t *rdev;
sector_t size;
rdev = (mdk_rdev_t *) kmalloc(sizeof(*rdev), GFP_KERNEL);
if (!rdev) {
printk(KERN_ERR "md: could not alloc mem for new device!\n");
return ERR_PTR(-ENOMEM);
}
memset(rdev, 0, sizeof(*rdev));
if ((err = alloc_disk_sb(rdev)))
goto abort_free;
err = lock_rdev(rdev, newdev);
if (err)
goto abort_free;
rdev->desc_nr = -1;
rdev->faulty = 0;
rdev->in_sync = 0;
rdev->data_offset = 0;
atomic_set(&rdev->nr_pending, 0);
size = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
if (!size) {
printk(KERN_WARNING
"md: %s has zero or unknown size, marking faulty!\n",
bdevname(rdev->bdev,b));
err = -EINVAL;
goto abort_free;
}
if (super_format >= 0) {
err = super_types[super_format].
load_super(rdev, NULL, super_minor);
if (err == -EINVAL) {
printk(KERN_WARNING
"md: %s has invalid sb, not importing!\n",
bdevname(rdev->bdev,b));
goto abort_free;
}
if (err < 0) {
printk(KERN_WARNING
"md: could not read %s's sb, not importing!\n",
bdevname(rdev->bdev,b));
goto abort_free;
}
}
INIT_LIST_HEAD(&rdev->same_set);
return rdev;
abort_free:
if (rdev->sb_page) {
if (rdev->bdev)
unlock_rdev(rdev);
free_disk_sb(rdev);
}
kfree(rdev);
return ERR_PTR(err);
}
/*
* Check a full RAID array for plausibility
*/
static void analyze_sbs(mddev_t * mddev)
{
int i;
struct list_head *tmp;
mdk_rdev_t *rdev, *freshest;
char b[BDEVNAME_SIZE];
freshest = NULL;
ITERATE_RDEV(mddev,rdev,tmp)
switch (super_types[mddev->major_version].
load_super(rdev, freshest, mddev->minor_version)) {
case 1:
freshest = rdev;
break;
case 0:
break;
default:
printk( KERN_ERR \
"md: fatal superblock inconsistency in %s"
" -- removing from array\n",
bdevname(rdev->bdev,b));
kick_rdev_from_array(rdev);
}
super_types[mddev->major_version].
validate_super(mddev, freshest);
i = 0;
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev != freshest)
if (super_types[mddev->major_version].
validate_super(mddev, rdev)) {
printk(KERN_WARNING "md: kicking non-fresh %s"
" from array!\n",
bdevname(rdev->bdev,b));
kick_rdev_from_array(rdev);
continue;
}
if (mddev->level == LEVEL_MULTIPATH) {
rdev->desc_nr = i++;
rdev->raid_disk = rdev->desc_nr;
rdev->in_sync = 1;
}
}
if (mddev->recovery_cp != MaxSector &&
mddev->level >= 1)
printk(KERN_ERR "md: %s: raid array is not clean"
" -- starting background reconstruction\n",
mdname(mddev));
}
int mdp_major = 0;
static struct kobject *md_probe(dev_t dev, int *part, void *data)
{
static DECLARE_MUTEX(disks_sem);
mddev_t *mddev = mddev_find(dev);
struct gendisk *disk;
int partitioned = (MAJOR(dev) != MD_MAJOR);
int shift = partitioned ? MdpMinorShift : 0;
int unit = MINOR(dev) >> shift;
if (!mddev)
return NULL;
down(&disks_sem);
if (mddev->gendisk) {
up(&disks_sem);
mddev_put(mddev);
return NULL;
}
disk = alloc_disk(1 << shift);
if (!disk) {
up(&disks_sem);
mddev_put(mddev);
return NULL;
}
disk->major = MAJOR(dev);
disk->first_minor = unit << shift;
if (partitioned) {
sprintf(disk->disk_name, "md_d%d", unit);
sprintf(disk->devfs_name, "md/d%d", unit);
} else {
sprintf(disk->disk_name, "md%d", unit);
sprintf(disk->devfs_name, "md/%d", unit);
}
disk->fops = &md_fops;
disk->private_data = mddev;
disk->queue = mddev->queue;
add_disk(disk);
mddev->gendisk = disk;
up(&disks_sem);
return NULL;
}
void md_wakeup_thread(mdk_thread_t *thread);
static void md_safemode_timeout(unsigned long data)
{
mddev_t *mddev = (mddev_t *) data;
mddev->safemode = 1;
md_wakeup_thread(mddev->thread);
}
static int do_md_run(mddev_t * mddev)
{
int pnum, err;
int chunk_size;
struct list_head *tmp;
mdk_rdev_t *rdev;
struct gendisk *disk;
char b[BDEVNAME_SIZE];
if (list_empty(&mddev->disks))
/* cannot run an array with no devices.. */
return -EINVAL;
if (mddev->pers)
return -EBUSY;
/*
* Analyze all RAID superblock(s)
*/
if (!mddev->raid_disks)
analyze_sbs(mddev);
chunk_size = mddev->chunk_size;
pnum = level_to_pers(mddev->level);
if ((pnum != MULTIPATH) && (pnum != RAID1)) {
if (!chunk_size) {
/*
* 'default chunksize' in the old md code used to
* be PAGE_SIZE, baaad.
* we abort here to be on the safe side. We don't
* want to continue the bad practice.
*/
printk(KERN_ERR
"no chunksize specified, see 'man raidtab'\n");
return -EINVAL;
}
if (chunk_size > MAX_CHUNK_SIZE) {
printk(KERN_ERR "too big chunk_size: %d > %d\n",
chunk_size, MAX_CHUNK_SIZE);
return -EINVAL;
}
/*
* chunk-size has to be a power of 2 and multiples of PAGE_SIZE
*/
if ( (1 << ffz(~chunk_size)) != chunk_size) {
printk(KERN_ERR "chunk_size of %d not valid\n", chunk_size);
return -EINVAL;
}
if (chunk_size < PAGE_SIZE) {
printk(KERN_ERR "too small chunk_size: %d < %ld\n",
chunk_size, PAGE_SIZE);
return -EINVAL;
}
/* devices must have minimum size of one chunk */
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->faulty)
continue;
if (rdev->size < chunk_size / 1024) {
printk(KERN_WARNING
"md: Dev %s smaller than chunk_size:"
" %lluk < %dk\n",
bdevname(rdev->bdev,b),
(unsigned long long)rdev->size,
chunk_size / 1024);
return -EINVAL;
}
}
}
#ifdef CONFIG_KMOD
if (!pers[pnum])
{
request_module("md-personality-%d", pnum);
}
#endif
/*
* Drop all container device buffers, from now on
* the only valid external interface is through the md
* device.
* Also find largest hardsector size
*/
ITERATE_RDEV(mddev,rdev,tmp) {
if (rdev->faulty)
continue;
sync_blockdev(rdev->bdev);
invalidate_bdev(rdev->bdev, 0);
}
md_probe(mddev->unit, NULL, NULL);
disk = mddev->gendisk;
if (!disk)
return -ENOMEM;
spin_lock(&pers_lock);
if (!pers[pnum] || !try_module_get(pers[pnum]->owner)) {
spin_unlock(&pers_lock);
printk(KERN_WARNING "md: personality %d is not loaded!\n",
pnum);
return -EINVAL;
}
mddev->pers = pers[pnum];
spin_unlock(&pers_lock);
mddev->recovery = 0;
mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
/* before we start the array running, initialise the bitmap */
err = bitmap_create(mddev);
if (err)
printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
mdname(mddev), err);
else
err = mddev->pers->run(mddev);
if (err) {
printk(KERN_ERR "md: pers->run() failed ...\n");
module_put(mddev->pers->owner);
mddev->pers = NULL;
bitmap_destroy(mddev);
return err;
}
atomic_set(&mddev->writes_pending,0);
mddev->safemode = 0;
mddev->safemode_timer.function = md_safemode_timeout;
mddev->safemode_timer.data = (unsigned long) mddev;
mddev->safemode_delay = (20 * HZ)/1000 +1; /* 20 msec delay */
mddev->in_sync = 1;
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
if (mddev->sb_dirty)
md_update_sb(mddev);
set_capacity(disk, mddev->array_size<<1);
/* If we call blk_queue_make_request here, it will
* re-initialise max_sectors etc which may have been
* refined inside -> run. So just set the bits we need to set.
* Most initialisation happended when we called
* blk_queue_make_request(..., md_fail_request)
* earlier.
*/
mddev->queue->queuedata = mddev;
mddev->queue->make_request_fn = mddev->pers->make_request;
mddev->changed = 1;
return 0;
}
static int restart_array(mddev_t *mddev)
{
struct gendisk *disk = mddev->gendisk;
int err;
/*
* Complain if it has no devices
*/
err = -ENXIO;
if (list_empty(&mddev->disks))
goto out;
if (mddev->pers) {
err = -EBUSY;
if (!mddev->ro)
goto out;
mddev->safemode = 0;
mddev->ro = 0;
set_disk_ro(disk, 0);
printk(KERN_INFO "md: %s switched to read-write mode.\n",
mdname(mddev));
/*
* Kick recovery or resync if necessary
*/
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
err = 0;
} else {
printk(KERN_ERR "md: %s has no personality assigned.\n",
mdname(mddev));
err = -EINVAL;
}
out:
return err;
}
static int do_md_stop(mddev_t * mddev, int ro)
{
int err = 0;
struct gendisk *disk = mddev->gendisk;
if (mddev->pers) {
if (atomic_read(&mddev->active)>2) {
printk("md: %s still in use.\n",mdname(mddev));
return -EBUSY;
}
if (mddev->sync_thread) {
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
md_unregister_thread(mddev->sync_thread);
mddev->sync_thread = NULL;
}
del_timer_sync(&mddev->safemode_timer);
invalidate_partition(disk, 0);
if (ro) {
err = -ENXIO;
if (mddev->ro)
goto out;
mddev->ro = 1;
} else {
bitmap_flush(mddev);
wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
if (mddev->ro)
set_disk_ro(disk, 0);
blk_queue_make_request(mddev->queue, md_fail_request);
mddev->pers->stop(mddev);
module_put(mddev->pers->owner);
mddev->pers = NULL;
if (mddev->ro)
mddev->ro = 0;
}
if (!mddev->in_sync) {
/* mark array as shutdown cleanly */
mddev->in_sync = 1;
md_update_sb(mddev);
}
if (ro)
set_disk_ro(disk, 1);
}
bitmap_destroy(mddev);
if (mddev->bitmap_file) {
atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
fput(mddev->bitmap_file);
mddev->bitmap_file = NULL;
}
mddev->bitmap_offset = 0;
/*
* Free resources if final stop
*/
if (!ro) {
struct gendisk *disk;
printk(KERN_INFO "md: %s stopped.\n", mdname(mddev));
export_array(mddev);
mddev->array_size = 0;
disk = mddev->gendisk;
if (disk)
set_capacity(disk, 0);
mddev->changed = 1;
} else
printk(KERN_INFO "md: %s switched to read-only mode.\n",
mdname(mddev));
err = 0;
out:
return err;
}
static void autorun_array(mddev_t *mddev)
{
mdk_rdev_t *rdev;
struct list_head *tmp;
int err;
if (list_empty(&mddev->disks))
return;
printk(KERN_INFO "md: running: ");
ITERATE_RDEV(mddev,rdev,tmp) {
char b[BDEVNAME_SIZE];
printk("<%s>", bdevname(rdev->bdev,b));
}
printk("\n");
err = do_md_run (mddev);
if (err) {
printk(KERN_WARNING "md: do_md_run() returned %d\n", err);
do_md_stop (mddev, 0);
}
}
/*
* lets try to run arrays based on all disks that have arrived
* until now. (those are in pending_raid_disks)
*
* the method: pick the first pending disk, collect all disks with
* the same UUID, remove all from the pending list and put them into
* the 'same_array' list. Then order this list based on superblock
* update time (freshest comes first), kick out 'old' disks and
* compare superblocks. If everything's fine then run it.
*
* If "unit" is allocated, then bump its reference count
*/
static void autorun_devices(int part)
{
struct list_head candidates;
struct list_head *tmp;
mdk_rdev_t *rdev0, *rdev;
mddev_t *mddev;
char b[BDEVNAME_SIZE];
printk(KERN_INFO "md: autorun ...\n");
while (!list_empty(&pending_raid_disks)) {
dev_t dev;
rdev0 = list_entry(pending_raid_disks.next,
mdk_rdev_t, same_set);
printk(KERN_INFO "md: considering %s ...\n",
bdevname(rdev0->bdev,b));
INIT_LIST_HEAD(&candidates);
ITERATE_RDEV_PENDING(rdev,tmp)
if (super_90_load(rdev, rdev0, 0) >= 0) {
printk(KERN_INFO "md: adding %s ...\n",
bdevname(rdev->bdev,b));
list_move(&rdev->same_set, &candidates);
}
/*
* now we have a set of devices, with all of them having
* mostly sane superblocks. It's time to allocate the
* mddev.
*/
if (rdev0->preferred_minor < 0 || rdev0->preferred_minor >= MAX_MD_DEVS) {
printk(KERN_INFO "md: unit number in %s is bad: %d\n",
bdevname(rdev0->bdev, b), rdev0->preferred_minor);
break;
}
if (part)
dev = MKDEV(mdp_major,
rdev0->preferred_minor << MdpMinorShift);
else
dev = MKDEV(MD_MAJOR, rdev0->preferred_minor);
md_probe(dev, NULL, NULL);
mddev = mddev_find(dev);
if (!mddev) {
printk(KERN_ERR
"md: cannot allocate memory for md drive.\n");
break;
}
if (mddev_lock(mddev))
printk(KERN_WARNING "md: %s locked, cannot run\n",
mdname(mddev));
else if (mddev->raid_disks || mddev->major_version
|| !list_empty(&mddev->disks)) {
printk(KERN_WARNING
"md: %s already running, cannot run %s\n",
mdname(mddev), bdevname(rdev0->bdev,b));
mddev_unlock(mddev);
} else {
printk(KERN_INFO "md: created %s\n", mdname(mddev));
ITERATE_RDEV_GENERIC(candidates,rdev,tmp) {
list_del_init(&rdev->same_set);
if (bind_rdev_to_array(rdev, mddev))
export_rdev(rdev);
}
autorun_array(mddev);
mddev_unlock(mddev);
}
/* on success, candidates will be empty, on error
* it won't...
*/
ITERATE_RDEV_GENERIC(candidates,rdev,tmp)
export_rdev(rdev);
mddev_put(mddev);
}
printk(KERN_INFO "md: ... autorun DONE.\n");
}
/*
* import RAID devices based on one partition
* if possible, the array gets run as well.
*/
static int autostart_array(dev_t startdev)
{
char b[BDEVNAME_SIZE];
int err = -EINVAL, i;
mdp_super_t *sb = NULL;
mdk_rdev_t *start_rdev = NULL, *rdev;
start_rdev = md_import_device(startdev, 0, 0);
if (IS_ERR(start_rdev))
return err;
/* NOTE: this can only work for 0.90.0 superblocks */
sb = (mdp_super_t*)page_address(start_rdev->sb_page);
if (sb->major_version != 0 ||
sb->minor_version != 90 ) {
printk(KERN_WARNING "md: can only autostart 0.90.0 arrays\n");
export_rdev(start_rdev);
return err;
}
if (start_rdev->faulty) {
printk(KERN_WARNING
"md: can not autostart based on faulty %s!\n",
bdevname(start_rdev->bdev,b));
export_rdev(start_rdev);
return err;
}
list_add(&start_rdev->same_set, &pending_raid_disks);
for (i = 0; i < MD_SB_DISKS; i++) {
mdp_disk_t *desc = sb->disks + i;
dev_t dev = MKDEV(desc->major, desc->minor);
if (!dev)
continue;
if (dev == startdev)
continue;
if (MAJOR(dev) != desc->major || MINOR(dev) != desc->minor)
continue;
rdev = md_import_device(dev, 0, 0);
if (IS_ERR(rdev))
continue;
list_add(&rdev->same_set, &pending_raid_disks);
}
/*
* possibly return codes
*/
autorun_devices(0);
return 0;
}
static int get_version(void __user * arg)
{
mdu_version_t ver;
ver.major = MD_MAJOR_VERSION;
ver.minor = MD_MINOR_VERSION;
ver.patchlevel = MD_PATCHLEVEL_VERSION;
if (copy_to_user(arg, &ver, sizeof(ver)))
return -EFAULT;
return 0;
}
static int get_array_info(mddev_t * mddev, void __user * arg)
{
mdu_array_info_t info;
int nr,working,active,failed,spare;
mdk_rdev_t *rdev;
struct list_head *tmp;
nr=working=active=failed=spare=0;
ITERATE_RDEV(mddev,rdev,tmp) {
nr++;
if (rdev->faulty)
failed++;
else {
working++;
if (rdev->in_sync)
active++;
else
spare++;
}
}
info.major_version = mddev->major_version;
info.minor_version = mddev->minor_version;
info.patch_version = MD_PATCHLEVEL_VERSION;
info.ctime = mddev->ctime;
info.level = mddev->level;
info.size = mddev->size;
info.nr_disks = nr;
info.raid_disks = mddev->raid_disks;
info.md_minor = mddev->md_minor;
info.not_persistent= !mddev->persistent;
info.utime = mddev->utime;
info.state = 0;
if (mddev->in_sync)
info.state = (1<<MD_SB_CLEAN);
if (mddev->bitmap && mddev->bitmap_offset)
info.state = (1<<MD_SB_BITMAP_PRESENT);
info.active_disks = active;
info.working_disks = working;
info.failed_disks = failed;
info.spare_disks = spare;
info.layout = mddev->layout;
info.chunk_size = mddev->chunk_size;
if (copy_to_user(arg, &info, sizeof(info)))
return -EFAULT;
return 0;
}
static int get_bitmap_file(mddev_t * mddev, void __user * arg)
{
mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
char *ptr, *buf = NULL;
int err = -ENOMEM;
file = kmalloc(sizeof(*file), GFP_KERNEL);
if (!file)
goto out;
/* bitmap disabled, zero the first byte and copy out */
if (!mddev->bitmap || !mddev->bitmap->file) {
file->pathname[0] = '\0';
goto copy_out;
}
buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
if (!buf)
goto out;
ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
if (!ptr)
goto out;
strcpy(file->pathname, ptr);
copy_out:
err = 0;
if (copy_to_user(arg, file, sizeof(*file)))
err = -EFAULT;
out:
kfree(buf);
kfree(file);
return err;
}
static int get_disk_info(mddev_t * mddev, void __user * arg)
{
mdu_disk_info_t info;
unsigned int nr;
mdk_rdev_t *rdev;
if (copy_from_user(&info, arg, sizeof(info)))
return -EFAULT;
nr = info.number;
rdev = find_rdev_nr(mddev, nr);
if (rdev) {
info.major = MAJOR(rdev->bdev->bd_dev);
info.minor = MINOR(rdev->bdev->bd_dev);
info.raid_disk = rdev->raid_disk;
info.state = 0;
if (rdev->faulty)
info.state |= (1<<MD_DISK_FAULTY);
else if (rdev->in_sync) {
info.state |= (1<<MD_DISK_ACTIVE);
info.state |= (1<<MD_DISK_SYNC);
}
if (test_bit(WriteMostly, &rdev->flags))
info.state |= (1<<MD_DISK_WRITEMOSTLY);
} else {
info.major = info.minor = 0;
info.raid_disk = -1;
info.state = (1<<MD_DISK_REMOVED);
}
if (copy_to_user(arg, &info, sizeof(info)))
return -EFAULT;
return 0;
}
static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
{
char b[BDEVNAME_SIZE], b2[BDEVNAME_SIZE];
mdk_rdev_t *rdev;
dev_t dev = MKDEV(info->major,info->minor);
if (info->major != MAJOR(dev) || info->minor != MINOR(dev))
return -EOVERFLOW;
if (!mddev->raid_disks) {
int err;
/* expecting a device which has a superblock */
rdev = md_import_device(dev, mddev->major_version, mddev->minor_version);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: md_import_device returned %ld\n",
PTR_ERR(rdev));
return PTR_ERR(rdev);
}
if (!list_empty(&mddev->disks)) {
mdk_rdev_t *rdev0 = list_entry(mddev->disks.next,
mdk_rdev_t, same_set);
int err = super_types[mddev->major_version]
.load_super(rdev, rdev0, mddev->minor_version);
if (err < 0) {
printk(KERN_WARNING
"md: %s has different UUID to %s\n",
bdevname(rdev->bdev,b),
bdevname(rdev0->bdev,b2));
export_rdev(rdev);
return -EINVAL;
}
}
err = bind_rdev_to_array(rdev, mddev);
if (err)
export_rdev(rdev);
return err;
}
/*
* add_new_disk can be used once the array is assembled
* to add "hot spares". They must already have a superblock
* written
*/
if (mddev->pers) {
int err;
if (!mddev->pers->hot_add_disk) {
printk(KERN_WARNING
"%s: personality does not support diskops!\n",
mdname(mddev));
return -EINVAL;
}
if (mddev->persistent)
rdev = md_import_device(dev, mddev->major_version,
mddev->minor_version);
else
rdev = md_import_device(dev, -1, -1);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: md_import_device returned %ld\n",
PTR_ERR(rdev));
return PTR_ERR(rdev);
}
/* set save_raid_disk if appropriate */
if (!mddev->persistent) {
if (info->state & (1<<MD_DISK_SYNC) &&
info->raid_disk < mddev->raid_disks)
rdev->raid_disk = info->raid_disk;
else
rdev->raid_disk = -1;
} else
super_types[mddev->major_version].
validate_super(mddev, rdev);
rdev->saved_raid_disk = rdev->raid_disk;
rdev->in_sync = 0; /* just to be sure */
if (info->state & (1<<MD_DISK_WRITEMOSTLY))
set_bit(WriteMostly, &rdev->flags);
rdev->raid_disk = -1;
err = bind_rdev_to_array(rdev, mddev);
if (err)
export_rdev(rdev);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
return err;
}
/* otherwise, add_new_disk is only allowed
* for major_version==0 superblocks
*/
if (mddev->major_version != 0) {
printk(KERN_WARNING "%s: ADD_NEW_DISK not supported\n",
mdname(mddev));
return -EINVAL;
}
if (!(info->state & (1<<MD_DISK_FAULTY))) {
int err;
rdev = md_import_device (dev, -1, 0);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: error, md_import_device() returned %ld\n",
PTR_ERR(rdev));
return PTR_ERR(rdev);
}
rdev->desc_nr = info->number;
if (info->raid_disk < mddev->raid_disks)
rdev->raid_disk = info->raid_disk;
else
rdev->raid_disk = -1;
rdev->faulty = 0;
if (rdev->raid_disk < mddev->raid_disks)
rdev->in_sync = (info->state & (1<<MD_DISK_SYNC));
else
rdev->in_sync = 0;
if (info->state & (1<<MD_DISK_WRITEMOSTLY))
set_bit(WriteMostly, &rdev->flags);
err = bind_rdev_to_array(rdev, mddev);
if (err) {
export_rdev(rdev);
return err;
}
if (!mddev->persistent) {
printk(KERN_INFO "md: nonpersistent superblock ...\n");
rdev->sb_offset = rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
} else
rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
rdev->size = calc_dev_size(rdev, mddev->chunk_size);
if (!mddev->size || (mddev->size > rdev->size))
mddev->size = rdev->size;
}
return 0;
}
static int hot_remove_disk(mddev_t * mddev, dev_t dev)
{
char b[BDEVNAME_SIZE];
mdk_rdev_t *rdev;
if (!mddev->pers)
return -ENODEV;
rdev = find_rdev(mddev, dev);
if (!rdev)
return -ENXIO;
if (rdev->raid_disk >= 0)
goto busy;
kick_rdev_from_array(rdev);
md_update_sb(mddev);
return 0;
busy:
printk(KERN_WARNING "md: cannot remove active disk %s from %s ... \n",
bdevname(rdev->bdev,b), mdname(mddev));
return -EBUSY;
}
static int hot_add_disk(mddev_t * mddev, dev_t dev)
{
char b[BDEVNAME_SIZE];
int err;
unsigned int size;
mdk_rdev_t *rdev;
if (!mddev->pers)
return -ENODEV;
if (mddev->major_version != 0) {
printk(KERN_WARNING "%s: HOT_ADD may only be used with"
" version-0 superblocks.\n",
mdname(mddev));
return -EINVAL;
}
if (!mddev->pers->hot_add_disk) {
printk(KERN_WARNING
"%s: personality does not support diskops!\n",
mdname(mddev));
return -EINVAL;
}
rdev = md_import_device (dev, -1, 0);
if (IS_ERR(rdev)) {
printk(KERN_WARNING
"md: error, md_import_device() returned %ld\n",
PTR_ERR(rdev));
return -EINVAL;
}
if (mddev->persistent)
rdev->sb_offset = calc_dev_sboffset(rdev->bdev);
else
rdev->sb_offset =
rdev->bdev->bd_inode->i_size >> BLOCK_SIZE_BITS;
size = calc_dev_size(rdev, mddev->chunk_size);
rdev->size = size;
if (size < mddev->size) {
printk(KERN_WARNING
"%s: disk size %llu blocks < array size %llu\n",
mdname(mddev), (unsigned long long)size,
(unsigned long long)mddev->size);
err = -ENOSPC;
goto abort_export;
}
if (rdev->faulty) {
printk(KERN_WARNING
"md: can not hot-add faulty %s disk to %s!\n",
bdevname(rdev->bdev,b), mdname(mddev));
err = -EINVAL;
goto abort_export;
}
rdev->in_sync = 0;
rdev->desc_nr = -1;
bind_rdev_to_array(rdev, mddev);
/*
* The rest should better be atomic, we can have disk failures
* noticed in interrupt contexts ...
*/
if (rdev->desc_nr == mddev->max_disks) {
printk(KERN_WARNING "%s: can not hot-add to full array!\n",
mdname(mddev));
err = -EBUSY;
goto abort_unbind_export;
}
rdev->raid_disk = -1;
md_update_sb(mddev);
/*
* Kick recovery, maybe this spare has to be added to the
* array immediately.
*/
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
return 0;
abort_unbind_export:
unbind_rdev_from_array(rdev);
abort_export:
export_rdev(rdev);
return err;
}
/* similar to deny_write_access, but accounts for our holding a reference
* to the file ourselves */
static int deny_bitmap_write_access(struct file * file)
{
struct inode *inode = file->f_mapping->host;
spin_lock(&inode->i_lock);
if (atomic_read(&inode->i_writecount) > 1) {
spin_unlock(&inode->i_lock);
return -ETXTBSY;
}
atomic_set(&inode->i_writecount, -1);
spin_unlock(&inode->i_lock);
return 0;
}
static int set_bitmap_file(mddev_t *mddev, int fd)
{
int err;
if (mddev->pers) {
if (!mddev->pers->quiesce)
return -EBUSY;
if (mddev->recovery || mddev->sync_thread)
return -EBUSY;
/* we should be able to change the bitmap.. */
}
if (fd >= 0) {
if (mddev->bitmap)
return -EEXIST; /* cannot add when bitmap is present */
mddev->bitmap_file = fget(fd);
if (mddev->bitmap_file == NULL) {
printk(KERN_ERR "%s: error: failed to get bitmap file\n",
mdname(mddev));
return -EBADF;
}
err = deny_bitmap_write_access(mddev->bitmap_file);
if (err) {
printk(KERN_ERR "%s: error: bitmap file is already in use\n",
mdname(mddev));
fput(mddev->bitmap_file);
mddev->bitmap_file = NULL;
return err;
}
mddev->bitmap_offset = 0; /* file overrides offset */
} else if (mddev->bitmap == NULL)
return -ENOENT; /* cannot remove what isn't there */
err = 0;
if (mddev->pers) {
mddev->pers->quiesce(mddev, 1);
if (fd >= 0)
err = bitmap_create(mddev);
if (fd < 0 || err)
bitmap_destroy(mddev);
mddev->pers->quiesce(mddev, 0);
} else if (fd < 0) {
if (mddev->bitmap_file)
fput(mddev->bitmap_file);
mddev->bitmap_file = NULL;
}
return err;
}
/*
* set_array_info is used two different ways
* The original usage is when creating a new array.
* In this usage, raid_disks is > 0 and it together with
* level, size, not_persistent,layout,chunksize determine the
* shape of the array.
* This will always create an array with a type-0.90.0 superblock.
* The newer usage is when assembling an array.
* In this case raid_disks will be 0, and the major_version field is
* use to determine which style super-blocks are to be found on the devices.
* The minor and patch _version numbers are also kept incase the
* super_block handler wishes to interpret them.
*/
static int set_array_info(mddev_t * mddev, mdu_array_info_t *info)
{
if (info->raid_disks == 0) {
/* just setting version number for superblock loading */
if (info->major_version < 0 ||
info->major_version >= sizeof(super_types)/sizeof(super_types[0]) ||
super_types[info->major_version].name == NULL) {
/* maybe try to auto-load a module? */
printk(KERN_INFO
"md: superblock version %d not known\n",
info->major_version);
return -EINVAL;
}
mddev->major_version = info->major_version;
mddev->minor_version = info->minor_version;
mddev->patch_version = info->patch_version;
return 0;
}
mddev->major_version = MD_MAJOR_VERSION;
mddev->minor_version = MD_MINOR_VERSION;
mddev->patch_version = MD_PATCHLEVEL_VERSION;
mddev->ctime = get_seconds();
mddev->level = info->level;
mddev->size = info->size;
mddev->raid_disks = info->raid_disks;
/* don't set md_minor, it is determined by which /dev/md* was
* openned
*/
if (info->state & (1<<MD_SB_CLEAN))
mddev->recovery_cp = MaxSector;
else
mddev->recovery_cp = 0;
mddev->persistent = ! info->not_persistent;
mddev->layout = info->layout;
mddev->chunk_size = info->chunk_size;
mddev->max_disks = MD_SB_DISKS;
mddev->sb_dirty = 1;
/*
* Generate a 128 bit UUID
*/
get_random_bytes(mddev->uuid, 16);
return 0;
}
/*
* update_array_info is used to change the configuration of an
* on-line array.
* The version, ctime,level,size,raid_disks,not_persistent, layout,chunk_size
* fields in the info are checked against the array.
* Any differences that cannot be handled will cause an error.
* Normally, only one change can be managed at a time.
*/
static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
{
int rv = 0;
int cnt = 0;
int state = 0;
/* calculate expected state,ignoring low bits */
if (mddev->bitmap && mddev->bitmap_offset)
state |= (1 << MD_SB_BITMAP_PRESENT);
if (mddev->major_version != info->major_version ||
mddev->minor_version != info->minor_version ||
/* mddev->patch_version != info->patch_version || */
mddev->ctime != info->ctime ||
mddev->level != info->level ||
/* mddev->layout != info->layout || */
!mddev->persistent != info->not_persistent||
mddev->chunk_size != info->chunk_size ||
/* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */
((state^info->state) & 0xfffffe00)
)
return -EINVAL;
/* Check there is only one change */
if (mddev->size != info->size) cnt++;
if (mddev->raid_disks != info->raid_disks) cnt++;
if (mddev->layout != info->layout) cnt++;
if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) cnt++;
if (cnt == 0) return 0;
if (cnt > 1) return -EINVAL;
if (mddev->layout != info->layout) {
/* Change layout
* we don't need to do anything at the md level, the
* personality will take care of it all.
*/
if (mddev->pers->reconfig == NULL)
return -EINVAL;
else
return mddev->pers->reconfig(mddev, info->layout, -1);
}
if (mddev->size != info->size) {
mdk_rdev_t * rdev;
struct list_head *tmp;
if (mddev->pers->resize == NULL)
return -EINVAL;
/* The "size" is the amount of each device that is used.
* This can only make sense for arrays with redundancy.
* linear and raid0 always use whatever space is available
* We can only consider changing the size if no resync
* or reconstruction is happening, and if the new size
* is acceptable. It must fit before the sb_offset or,
* if that is <data_offset, it must fit before the
* size of each device.
* If size is zero, we find the largest size that fits.
*/
if (mddev->sync_thread)
return -EBUSY;
ITERATE_RDEV(mddev,rdev,tmp) {
sector_t avail;
int fit = (info->size == 0);
if (rdev->sb_offset > rdev->data_offset)
avail = (rdev->sb_offset*2) - rdev->data_offset;
else
avail = get_capacity(rdev->bdev->bd_disk)
- rdev->data_offset;
if (fit && (info->size == 0 || info->size > avail/2))
info->size = avail/2;
if (avail < ((sector_t)info->size << 1))
return -ENOSPC;
}
rv = mddev->pers->resize(mddev, (sector_t)info->size *2);
if (!rv) {
struct block_device *bdev;
bdev = bdget_disk(mddev->gendisk, 0);
if (bdev) {
down(&bdev->bd_inode->i_sem);
i_size_write(bdev->bd_inode, mddev->array_size << 10);
up(&bdev->bd_inode->i_sem);
bdput(bdev);
}
}
}
if (mddev->raid_disks != info->raid_disks) {
/* change the number of raid disks */
if (mddev->pers->reshape == NULL)
return -EINVAL;
if (info->raid_disks <= 0 ||
info->raid_disks >= mddev->max_disks)
return -EINVAL;
if (mddev->sync_thread)
return -EBUSY;
rv = mddev->pers->reshape(mddev, info->raid_disks);
if (!rv) {
struct block_device *bdev;
bdev = bdget_disk(mddev->gendisk, 0);
if (bdev) {
down(&bdev->bd_inode->i_sem);
i_size_write(bdev->bd_inode, mddev->array_size << 10);
up(&bdev->bd_inode->i_sem);
bdput(bdev);
}
}
}
if ((state ^ info->state) & (1<<MD_SB_BITMAP_PRESENT)) {
if (mddev->pers->quiesce == NULL)
return -EINVAL;
if (mddev->recovery || mddev->sync_thread)
return -EBUSY;
if (info->state & (1<<MD_SB_BITMAP_PRESENT)) {
/* add the bitmap */
if (mddev->bitmap)
return -EEXIST;
if (mddev->default_bitmap_offset == 0)
return -EINVAL;
mddev->bitmap_offset = mddev->default_bitmap_offset;
mddev->pers->quiesce(mddev, 1);
rv = bitmap_create(mddev);
if (rv)
bitmap_destroy(mddev);
mddev->pers->quiesce(mddev, 0);
} else {
/* remove the bitmap */
if (!mddev->bitmap)
return -ENOENT;
if (mddev->bitmap->file)
return -EINVAL;
mddev->pers->quiesce(mddev, 1);
bitmap_destroy(mddev);
mddev->pers->quiesce(mddev, 0);
mddev->bitmap_offset = 0;
}
}
md_update_sb(mddev);
return rv;
}
static int set_disk_faulty(mddev_t *mddev, dev_t dev)
{
mdk_rdev_t *rdev;
if (mddev->pers == NULL)
return -ENODEV;
rdev = find_rdev(mddev, dev);
if (!rdev)
return -ENODEV;
md_error(mddev, rdev);
return 0;
}
static int md_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
int err = 0;
void __user *argp = (void __user *)arg;
struct hd_geometry __user *loc = argp;
mddev_t *mddev = NULL;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
/*
* Commands dealing with the RAID driver but not any
* particular array:
*/
switch (cmd)
{
case RAID_VERSION:
err = get_version(argp);
goto done;
case PRINT_RAID_DEBUG:
err = 0;
md_print_devices();
goto done;
#ifndef MODULE
case RAID_AUTORUN:
err = 0;
autostart_arrays(arg);
goto done;
#endif
default:;
}
/*
* Commands creating/starting a new array:
*/
mddev = inode->i_bdev->bd_disk->private_data;
if (!mddev) {
BUG();
goto abort;
}
if (cmd == START_ARRAY) {
/* START_ARRAY doesn't need to lock the array as autostart_array
* does the locking, and it could even be a different array
*/
static int cnt = 3;
if (cnt > 0 ) {
printk(KERN_WARNING
"md: %s(pid %d) used deprecated START_ARRAY ioctl. "
"This will not be supported beyond 2.6\n",
current->comm, current->pid);
cnt--;
}
err = autostart_array(new_decode_dev(arg));
if (err) {
printk(KERN_WARNING "md: autostart failed!\n");
goto abort;
}
goto done;
}
err = mddev_lock(mddev);
if (err) {
printk(KERN_INFO
"md: ioctl lock interrupted, reason %d, cmd %d\n",
err, cmd);
goto abort;
}
switch (cmd)
{
case SET_ARRAY_INFO:
{
mdu_array_info_t info;
if (!arg)
memset(&info, 0, sizeof(info));
else if (copy_from_user(&info, argp, sizeof(info))) {
err = -EFAULT;
goto abort_unlock;
}
if (mddev->pers) {
err = update_array_info(mddev, &info);
if (err) {
printk(KERN_WARNING "md: couldn't update"
" array info. %d\n", err);
goto abort_unlock;
}
goto done_unlock;
}
if (!list_empty(&mddev->disks)) {
printk(KERN_WARNING
"md: array %s already has disks!\n",
mdname(mddev));
err = -EBUSY;
goto abort_unlock;
}
if (mddev->raid_disks) {
printk(KERN_WARNING
"md: array %s already initialised!\n",
mdname(mddev));
err = -EBUSY;
goto abort_unlock;
}
err = set_array_info(mddev, &info);
if (err) {
printk(KERN_WARNING "md: couldn't set"
" array info. %d\n", err);
goto abort_unlock;
}
}
goto done_unlock;
default:;
}
/*
* Commands querying/configuring an existing array:
*/
/* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
* RUN_ARRAY, and SET_BITMAP_FILE are allowed */
if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
&& cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
err = -ENODEV;
goto abort_unlock;
}
/*
* Commands even a read-only array can execute:
*/
switch (cmd)
{
case GET_ARRAY_INFO:
err = get_array_info(mddev, argp);
goto done_unlock;
case GET_BITMAP_FILE:
err = get_bitmap_file(mddev, argp);
goto done_unlock;
case GET_DISK_INFO:
err = get_disk_info(mddev, argp);
goto done_unlock;
case RESTART_ARRAY_RW:
err = restart_array(mddev);
goto done_unlock;
case STOP_ARRAY:
err = do_md_stop (mddev, 0);
goto done_unlock;
case STOP_ARRAY_RO:
err = do_md_stop (mddev, 1);
goto done_unlock;
/*
* We have a problem here : there is no easy way to give a CHS
* virtual geometry. We currently pretend that we have a 2 heads
* 4 sectors (with a BIG number of cylinders...). This drives
* dosfs just mad... ;-)
*/
case HDIO_GETGEO:
if (!loc) {
err = -EINVAL;
goto abort_unlock;
}
err = put_user (2, (char __user *) &loc->heads);
if (err)
goto abort_unlock;
err = put_user (4, (char __user *) &loc->sectors);
if (err)
goto abort_unlock;
err = put_user(get_capacity(mddev->gendisk)/8,
(short __user *) &loc->cylinders);
if (err)
goto abort_unlock;
err = put_user (get_start_sect(inode->i_bdev),
(long __user *) &loc->start);
goto done_unlock;
}
/*
* The remaining ioctls are changing the state of the
* superblock, so we do not allow read-only arrays
* here:
*/
if (mddev->ro) {
err = -EROFS;
goto abort_unlock;
}
switch (cmd)
{
case ADD_NEW_DISK:
{
mdu_disk_info_t info;
if (copy_from_user(&info, argp, sizeof(info)))
err = -EFAULT;
else
err = add_new_disk(mddev, &info);
goto done_unlock;
}
case HOT_REMOVE_DISK:
err = hot_remove_disk(mddev, new_decode_dev(arg));
goto done_unlock;
case HOT_ADD_DISK:
err = hot_add_disk(mddev, new_decode_dev(arg));
goto done_unlock;
case SET_DISK_FAULTY:
err = set_disk_faulty(mddev, new_decode_dev(arg));
goto done_unlock;
case RUN_ARRAY:
err = do_md_run (mddev);
goto done_unlock;
case SET_BITMAP_FILE:
err = set_bitmap_file(mddev, (int)arg);
goto done_unlock;
default:
if (_IOC_TYPE(cmd) == MD_MAJOR)
printk(KERN_WARNING "md: %s(pid %d) used"
" obsolete MD ioctl, upgrade your"
" software to use new ictls.\n",
current->comm, current->pid);
err = -EINVAL;
goto abort_unlock;
}
done_unlock:
abort_unlock:
mddev_unlock(mddev);
return err;
done:
if (err)
MD_BUG();
abort:
return err;
}
static int md_open(struct inode *inode, struct file *file)
{
/*
* Succeed if we can lock the mddev, which confirms that
* it isn't being stopped right now.
*/
mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
int err;
if ((err = mddev_lock(mddev)))
goto out;
err = 0;
mddev_get(mddev);
mddev_unlock(mddev);
check_disk_change(inode->i_bdev);
out:
return err;
}
static int md_release(struct inode *inode, struct file * file)
{
mddev_t *mddev = inode->i_bdev->bd_disk->private_data;
if (!mddev)
BUG();
mddev_put(mddev);
return 0;
}
static int md_media_changed(struct gendisk *disk)
{
mddev_t *mddev = disk->private_data;
return mddev->changed;
}
static int md_revalidate(struct gendisk *disk)
{
mddev_t *mddev = disk->private_data;
mddev->changed = 0;
return 0;
}
static struct block_device_operations md_fops =
{
.owner = THIS_MODULE,
.open = md_open,
.release = md_release,
.ioctl = md_ioctl,
.media_changed = md_media_changed,
.revalidate_disk= md_revalidate,
};
static int md_thread(void * arg)
{
mdk_thread_t *thread = arg;
/*
* md_thread is a 'system-thread', it's priority should be very
* high. We avoid resource deadlocks individually in each
* raid personality. (RAID5 does preallocation) We also use RR and
* the very same RT priority as kswapd, thus we will never get
* into a priority inversion deadlock.
*
* we definitely have to have equal or higher priority than
* bdflush, otherwise bdflush will deadlock if there are too
* many dirty RAID5 blocks.
*/
allow_signal(SIGKILL);
complete(thread->event);
while (!kthread_should_stop()) {
void (*run)(mddev_t *);
wait_event_interruptible_timeout(thread->wqueue,
test_bit(THREAD_WAKEUP, &thread->flags)
|| kthread_should_stop(),
thread->timeout);
try_to_freeze();
clear_bit(THREAD_WAKEUP, &thread->flags);
run = thread->run;
if (run)
run(thread->mddev);
}
return 0;
}
void md_wakeup_thread(mdk_thread_t *thread)
{
if (thread) {
dprintk("md: waking up MD thread %s.\n", thread->tsk->comm);
set_bit(THREAD_WAKEUP, &thread->flags);
wake_up(&thread->wqueue);
}
}
mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
const char *name)
{
mdk_thread_t *thread;
struct completion event;
thread = kmalloc(sizeof(mdk_thread_t), GFP_KERNEL);
if (!thread)
return NULL;
memset(thread, 0, sizeof(mdk_thread_t));
init_waitqueue_head(&thread->wqueue);
init_completion(&event);
thread->event = &event;
thread->run = run;
thread->mddev = mddev;
thread->name = name;
thread->timeout = MAX_SCHEDULE_TIMEOUT;
thread->tsk = kthread_run(md_thread, thread, name, mdname(thread->mddev));
if (IS_ERR(thread->tsk)) {
kfree(thread);
return NULL;
}
wait_for_completion(&event);
return thread;
}
void md_unregister_thread(mdk_thread_t *thread)
{
dprintk("interrupting MD-thread pid %d\n", thread->tsk->pid);
kthread_stop(thread->tsk);
kfree(thread);
}
void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
{
if (!mddev) {
MD_BUG();
return;
}
if (!rdev || rdev->faulty)
return;
/*
dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
mdname(mddev),
MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
__builtin_return_address(0),__builtin_return_address(1),
__builtin_return_address(2),__builtin_return_address(3));
*/
if (!mddev->pers->error_handler)
return;
mddev->pers->error_handler(mddev,rdev);
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
}
/* seq_file implementation /proc/mdstat */
static void status_unused(struct seq_file *seq)
{
int i = 0;
mdk_rdev_t *rdev;
struct list_head *tmp;
seq_printf(seq, "unused devices: ");
ITERATE_RDEV_PENDING(rdev,tmp) {
char b[BDEVNAME_SIZE];
i++;
seq_printf(seq, "%s ",
bdevname(rdev->bdev,b));
}
if (!i)
seq_printf(seq, "<none>");
seq_printf(seq, "\n");
}
static void status_resync(struct seq_file *seq, mddev_t * mddev)
{
unsigned long max_blocks, resync, res, dt, db, rt;
resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
max_blocks = mddev->resync_max_sectors >> 1;
else
max_blocks = mddev->size;
/*
* Should not happen.
*/
if (!max_blocks) {
MD_BUG();
return;
}
res = (resync/1024)*1000/(max_blocks/1024 + 1);
{
int i, x = res/50, y = 20-x;
seq_printf(seq, "[");
for (i = 0; i < x; i++)
seq_printf(seq, "=");
seq_printf(seq, ">");
for (i = 0; i < y; i++)
seq_printf(seq, ".");
seq_printf(seq, "] ");
}
seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
(test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
"resync" : "recovery"),
res/10, res % 10, resync, max_blocks);
/*
* We do not want to overflow, so the order of operands and
* the * 100 / 100 trick are important. We do a +1 to be
* safe against division by zero. We only estimate anyway.
*
* dt: time from mark until now
* db: blocks written from mark until now
* rt: remaining time
*/
dt = ((jiffies - mddev->resync_mark) / HZ);
if (!dt) dt++;
db = resync - (mddev->resync_mark_cnt/2);
rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);
seq_printf(seq, " speed=%ldK/sec", db/dt);
}
static void *md_seq_start(struct seq_file *seq, loff_t *pos)
{
struct list_head *tmp;
loff_t l = *pos;
mddev_t *mddev;
if (l >= 0x10000)
return NULL;
if (!l--)
/* header */
return (void*)1;
spin_lock(&all_mddevs_lock);
list_for_each(tmp,&all_mddevs)
if (!l--) {
mddev = list_entry(tmp, mddev_t, all_mddevs);
mddev_get(mddev);
spin_unlock(&all_mddevs_lock);
return mddev;
}
spin_unlock(&all_mddevs_lock);
if (!l--)
return (void*)2;/* tail */
return NULL;
}
static void *md_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct list_head *tmp;
mddev_t *next_mddev, *mddev = v;
++*pos;
if (v == (void*)2)
return NULL;
spin_lock(&all_mddevs_lock);
if (v == (void*)1)
tmp = all_mddevs.next;
else
tmp = mddev->all_mddevs.next;
if (tmp != &all_mddevs)
next_mddev = mddev_get(list_entry(tmp,mddev_t,all_mddevs));
else {
next_mddev = (void*)2;
*pos = 0x10000;
}
spin_unlock(&all_mddevs_lock);
if (v != (void*)1)
mddev_put(mddev);
return next_mddev;
}
static void md_seq_stop(struct seq_file *seq, void *v)
{
mddev_t *mddev = v;
if (mddev && v != (void*)1 && v != (void*)2)
mddev_put(mddev);
}
static int md_seq_show(struct seq_file *seq, void *v)
{
mddev_t *mddev = v;
sector_t size;
struct list_head *tmp2;
mdk_rdev_t *rdev;
int i;
struct bitmap *bitmap;
if (v == (void*)1) {
seq_printf(seq, "Personalities : ");
spin_lock(&pers_lock);
for (i = 0; i < MAX_PERSONALITY; i++)
if (pers[i])
seq_printf(seq, "[%s] ", pers[i]->name);
spin_unlock(&pers_lock);
seq_printf(seq, "\n");
return 0;
}
if (v == (void*)2) {
status_unused(seq);
return 0;
}
if (mddev_lock(mddev)!=0)
return -EINTR;
if (mddev->pers || mddev->raid_disks || !list_empty(&mddev->disks)) {
seq_printf(seq, "%s : %sactive", mdname(mddev),
mddev->pers ? "" : "in");
if (mddev->pers) {
if (mddev->ro)
seq_printf(seq, " (read-only)");
seq_printf(seq, " %s", mddev->pers->name);
}
size = 0;
ITERATE_RDEV(mddev,rdev,tmp2) {
char b[BDEVNAME_SIZE];
seq_printf(seq, " %s[%d]",
bdevname(rdev->bdev,b), rdev->desc_nr);
if (test_bit(WriteMostly, &rdev->flags))
seq_printf(seq, "(W)");
if (rdev->faulty) {
seq_printf(seq, "(F)");
continue;
} else if (rdev->raid_disk < 0)
seq_printf(seq, "(S)"); /* spare */
size += rdev->size;
}
if (!list_empty(&mddev->disks)) {
if (mddev->pers)
seq_printf(seq, "\n %llu blocks",
(unsigned long long)mddev->array_size);
else
seq_printf(seq, "\n %llu blocks",
(unsigned long long)size);
}
if (mddev->persistent) {
if (mddev->major_version != 0 ||
mddev->minor_version != 90) {
seq_printf(seq," super %d.%d",
mddev->major_version,
mddev->minor_version);
}
} else
seq_printf(seq, " super non-persistent");
if (mddev->pers) {
mddev->pers->status (seq, mddev);
seq_printf(seq, "\n ");
if (mddev->curr_resync > 2) {
status_resync (seq, mddev);
seq_printf(seq, "\n ");
} else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
seq_printf(seq, " resync=DELAYED\n ");
} else
seq_printf(seq, "\n ");
if ((bitmap = mddev->bitmap)) {
unsigned long chunk_kb;
unsigned long flags;
spin_lock_irqsave(&bitmap->lock, flags);
chunk_kb = bitmap->chunksize >> 10;
seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
"%lu%s chunk",
bitmap->pages - bitmap->missing_pages,
bitmap->pages,
(bitmap->pages - bitmap->missing_pages)
<< (PAGE_SHIFT - 10),
chunk_kb ? chunk_kb : bitmap->chunksize,
chunk_kb ? "KB" : "B");
if (bitmap->file) {
seq_printf(seq, ", file: ");
seq_path(seq, bitmap->file->f_vfsmnt,
bitmap->file->f_dentry," \t\n");
}
seq_printf(seq, "\n");
spin_unlock_irqrestore(&bitmap->lock, flags);
}
seq_printf(seq, "\n");
}
mddev_unlock(mddev);
return 0;
}
static struct seq_operations md_seq_ops = {
.start = md_seq_start,
.next = md_seq_next,
.stop = md_seq_stop,
.show = md_seq_show,
};
static int md_seq_open(struct inode *inode, struct file *file)
{
int error;
error = seq_open(file, &md_seq_ops);
return error;
}
static struct file_operations md_seq_fops = {
.open = md_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
int register_md_personality(int pnum, mdk_personality_t *p)
{
if (pnum >= MAX_PERSONALITY) {
printk(KERN_ERR
"md: tried to install personality %s as nr %d, but max is %lu\n",
p->name, pnum, MAX_PERSONALITY-1);
return -EINVAL;
}
spin_lock(&pers_lock);
if (pers[pnum]) {
spin_unlock(&pers_lock);
return -EBUSY;
}
pers[pnum] = p;
printk(KERN_INFO "md: %s personality registered as nr %d\n", p->name, pnum);
spin_unlock(&pers_lock);
return 0;
}
int unregister_md_personality(int pnum)
{
if (pnum >= MAX_PERSONALITY)
return -EINVAL;
printk(KERN_INFO "md: %s personality unregistered\n", pers[pnum]->name);
spin_lock(&pers_lock);
pers[pnum] = NULL;
spin_unlock(&pers_lock);
return 0;
}
static int is_mddev_idle(mddev_t *mddev)
{
mdk_rdev_t * rdev;
struct list_head *tmp;
int idle;
unsigned long curr_events;
idle = 1;
ITERATE_RDEV(mddev,rdev,tmp) {
struct gendisk *disk = rdev->bdev->bd_contains->bd_disk;
curr_events = disk_stat_read(disk, sectors[0]) +
disk_stat_read(disk, sectors[1]) -
atomic_read(&disk->sync_io);
/* Allow some slack between valud of curr_events and last_events,
* as there are some uninteresting races.
* Note: the following is an unsigned comparison.
*/
if ((curr_events - rdev->last_events + 32) > 64) {
rdev->last_events = curr_events;
idle = 0;
}
}
return idle;
}
void md_done_sync(mddev_t *mddev, int blocks, int ok)
{
/* another "blocks" (512byte) blocks have been synced */
atomic_sub(blocks, &mddev->recovery_active);
wake_up(&mddev->recovery_wait);
if (!ok) {
set_bit(MD_RECOVERY_ERR, &mddev->recovery);
md_wakeup_thread(mddev->thread);
// stop recovery, signal do_sync ....
}
}
/* md_write_start(mddev, bi)
* If we need to update some array metadata (e.g. 'active' flag
* in superblock) before writing, schedule a superblock update
* and wait for it to complete.
*/
void md_write_start(mddev_t *mddev, struct bio *bi)
{
if (bio_data_dir(bi) != WRITE)
return;
atomic_inc(&mddev->writes_pending);
if (mddev->in_sync) {
spin_lock(&mddev->write_lock);
if (mddev->in_sync) {
mddev->in_sync = 0;
mddev->sb_dirty = 1;
md_wakeup_thread(mddev->thread);
}
spin_unlock(&mddev->write_lock);
}
wait_event(mddev->sb_wait, mddev->sb_dirty==0);
}
void md_write_end(mddev_t *mddev)
{
if (atomic_dec_and_test(&mddev->writes_pending)) {
if (mddev->safemode == 2)
md_wakeup_thread(mddev->thread);
else
mod_timer(&mddev->safemode_timer, jiffies + mddev->safemode_delay);
}
}
static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
#define SYNC_MARKS 10
#define SYNC_MARK_STEP (3*HZ)
static void md_do_sync(mddev_t *mddev)
{
mddev_t *mddev2;
unsigned int currspeed = 0,
window;
sector_t max_sectors,j, io_sectors;
unsigned long mark[SYNC_MARKS];
sector_t mark_cnt[SYNC_MARKS];
int last_mark,m;
struct list_head *tmp;
sector_t last_check;
int skipped = 0;
/* just incase thread restarts... */
if (test_bit(MD_RECOVERY_DONE, &mddev->recovery))
return;
/* we overload curr_resync somewhat here.
* 0 == not engaged in resync at all
* 2 == checking that there is no conflict with another sync
* 1 == like 2, but have yielded to allow conflicting resync to
* commense
* other == active in resync - this many blocks
*
* Before starting a resync we must have set curr_resync to
* 2, and then checked that every "conflicting" array has curr_resync
* less than ours. When we find one that is the same or higher
* we wait on resync_wait. To avoid deadlock, we reduce curr_resync
* to 1 if we choose to yield (based arbitrarily on address of mddev structure).
* This will mean we have to start checking from the beginning again.
*
*/
do {
mddev->curr_resync = 2;
try_again:
if (signal_pending(current) ||
kthread_should_stop()) {
flush_signals(current);
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
goto skip;
}
ITERATE_MDDEV(mddev2,tmp) {
if (mddev2 == mddev)
continue;
if (mddev2->curr_resync &&
match_mddev_units(mddev,mddev2)) {
DEFINE_WAIT(wq);
if (mddev < mddev2 && mddev->curr_resync == 2) {
/* arbitrarily yield */
mddev->curr_resync = 1;
wake_up(&resync_wait);
}
if (mddev > mddev2 && mddev->curr_resync == 1)
/* no need to wait here, we can wait the next
* time 'round when curr_resync == 2
*/
continue;
prepare_to_wait(&resync_wait, &wq, TASK_INTERRUPTIBLE);
if (!signal_pending(current) &&
!kthread_should_stop() &&
mddev2->curr_resync >= mddev->curr_resync) {
printk(KERN_INFO "md: delaying resync of %s"
" until %s has finished resync (they"
" share one or more physical units)\n",
mdname(mddev), mdname(mddev2));
mddev_put(mddev2);
schedule();
finish_wait(&resync_wait, &wq);
goto try_again;
}
finish_wait(&resync_wait, &wq);
}
}
} while (mddev->curr_resync < 2);
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
/* resync follows the size requested by the personality,
* which defaults to physical size, but can be virtual size
*/
max_sectors = mddev->resync_max_sectors;
else
/* recovery follows the physical size of devices */
max_sectors = mddev->size << 1;
printk(KERN_INFO "md: syncing RAID array %s\n", mdname(mddev));
printk(KERN_INFO "md: minimum _guaranteed_ reconstruction speed:"
" %d KB/sec/disc.\n", sysctl_speed_limit_min);
printk(KERN_INFO "md: using maximum available idle IO bandwidth "
"(but not more than %d KB/sec) for reconstruction.\n",
sysctl_speed_limit_max);
is_mddev_idle(mddev); /* this also initializes IO event counters */
/* we don't use the checkpoint if there's a bitmap */
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap)
j = mddev->recovery_cp;
else
j = 0;
io_sectors = 0;
for (m = 0; m < SYNC_MARKS; m++) {
mark[m] = jiffies;
mark_cnt[m] = io_sectors;
}
last_mark = 0;
mddev->resync_mark = mark[last_mark];
mddev->resync_mark_cnt = mark_cnt[last_mark];
/*
* Tune reconstruction:
*/
window = 32*(PAGE_SIZE/512);
printk(KERN_INFO "md: using %dk window, over a total of %llu blocks.\n",
window/2,(unsigned long long) max_sectors/2);
atomic_set(&mddev->recovery_active, 0);
init_waitqueue_head(&mddev->recovery_wait);
last_check = 0;
if (j>2) {
printk(KERN_INFO
"md: resuming recovery of %s from checkpoint.\n",
mdname(mddev));
mddev->curr_resync = j;
}
while (j < max_sectors) {
sector_t sectors;
skipped = 0;
sectors = mddev->pers->sync_request(mddev, j, &skipped,
currspeed < sysctl_speed_limit_min);
if (sectors == 0) {
set_bit(MD_RECOVERY_ERR, &mddev->recovery);
goto out;
}
if (!skipped) { /* actual IO requested */
io_sectors += sectors;
atomic_add(sectors, &mddev->recovery_active);
}
j += sectors;
if (j>1) mddev->curr_resync = j;
if (last_check + window > io_sectors || j == max_sectors)
continue;
last_check = io_sectors;
if (test_bit(MD_RECOVERY_INTR, &mddev->recovery) ||
test_bit(MD_RECOVERY_ERR, &mddev->recovery))
break;
repeat:
if (time_after_eq(jiffies, mark[last_mark] + SYNC_MARK_STEP )) {
/* step marks */
int next = (last_mark+1) % SYNC_MARKS;
mddev->resync_mark = mark[next];
mddev->resync_mark_cnt = mark_cnt[next];
mark[next] = jiffies;
mark_cnt[next] = io_sectors - atomic_read(&mddev->recovery_active);
last_mark = next;
}
if (signal_pending(current) || kthread_should_stop()) {
/*
* got a signal, exit.
*/
printk(KERN_INFO
"md: md_do_sync() got signal ... exiting\n");
flush_signals(current);
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
goto out;
}
/*
* this loop exits only if either when we are slower than
* the 'hard' speed limit, or the system was IO-idle for
* a jiffy.
* the system might be non-idle CPU-wise, but we only care
* about not overloading the IO subsystem. (things like an
* e2fsck being done on the RAID array should execute fast)
*/
mddev->queue->unplug_fn(mddev->queue);
cond_resched();
currspeed = ((unsigned long)(io_sectors-mddev->resync_mark_cnt))/2
/((jiffies-mddev->resync_mark)/HZ +1) +1;
if (currspeed > sysctl_speed_limit_min) {
if ((currspeed > sysctl_speed_limit_max) ||
!is_mddev_idle(mddev)) {
msleep_interruptible(250);
goto repeat;
}
}
}
printk(KERN_INFO "md: %s: sync done.\n",mdname(mddev));
/*
* this also signals 'finished resyncing' to md_stop
*/
out:
mddev->queue->unplug_fn(mddev->queue);
wait_event(mddev->recovery_wait, !atomic_read(&mddev->recovery_active));
/* tell personality that we are finished */
mddev->pers->sync_request(mddev, max_sectors, &skipped, 1);
if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
mddev->curr_resync > 2 &&
mddev->curr_resync >= mddev->recovery_cp) {
if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
printk(KERN_INFO
"md: checkpointing recovery of %s.\n",
mdname(mddev));
mddev->recovery_cp = mddev->curr_resync;
} else
mddev->recovery_cp = MaxSector;
}
skip:
mddev->curr_resync = 0;
wake_up(&resync_wait);
set_bit(MD_RECOVERY_DONE, &mddev->recovery);
md_wakeup_thread(mddev->thread);
}
/*
* This routine is regularly called by all per-raid-array threads to
* deal with generic issues like resync and super-block update.
* Raid personalities that don't have a thread (linear/raid0) do not
* need this as they never do any recovery or update the superblock.
*
* It does not do any resync itself, but rather "forks" off other threads
* to do that as needed.
* When it is determined that resync is needed, we set MD_RECOVERY_RUNNING in
* "->recovery" and create a thread at ->sync_thread.
* When the thread finishes it sets MD_RECOVERY_DONE (and might set MD_RECOVERY_ERR)
* and wakeups up this thread which will reap the thread and finish up.
* This thread also removes any faulty devices (with nr_pending == 0).
*
* The overall approach is:
* 1/ if the superblock needs updating, update it.
* 2/ If a recovery thread is running, don't do anything else.
* 3/ If recovery has finished, clean up, possibly marking spares active.
* 4/ If there are any faulty devices, remove them.
* 5/ If array is degraded, try to add spares devices
* 6/ If array has spares or is not in-sync, start a resync thread.
*/
void md_check_recovery(mddev_t *mddev)
{
mdk_rdev_t *rdev;
struct list_head *rtmp;
if (mddev->bitmap)
bitmap_daemon_work(mddev->bitmap);
if (mddev->ro)
return;
if (signal_pending(current)) {
if (mddev->pers->sync_request) {
printk(KERN_INFO "md: %s in immediate safe mode\n",
mdname(mddev));
mddev->safemode = 2;
}
flush_signals(current);
}
if ( ! (
mddev->sb_dirty ||
test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) ||
test_bit(MD_RECOVERY_DONE, &mddev->recovery) ||
(mddev->safemode == 1) ||
(mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending)
&& !mddev->in_sync && mddev->recovery_cp == MaxSector)
))
return;
if (mddev_trylock(mddev)==0) {
int spares =0;
spin_lock(&mddev->write_lock);
if (mddev->safemode && !atomic_read(&mddev->writes_pending) &&
!mddev->in_sync && mddev->recovery_cp == MaxSector) {
mddev->in_sync = 1;
mddev->sb_dirty = 1;
}
if (mddev->safemode == 1)
mddev->safemode = 0;
spin_unlock(&mddev->write_lock);
if (mddev->sb_dirty)
md_update_sb(mddev);
if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) &&
!test_bit(MD_RECOVERY_DONE, &mddev->recovery)) {
/* resync/recovery still happening */
clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
goto unlock;
}
if (mddev->sync_thread) {
/* resync has finished, collect result */
md_unregister_thread(mddev->sync_thread);
mddev->sync_thread = NULL;
if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) &&
!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
/* success...*/
/* activate any spares */
mddev->pers->spare_active(mddev);
}
md_update_sb(mddev);
/* if array is no-longer degraded, then any saved_raid_disk
* information must be scrapped
*/
if (!mddev->degraded)
ITERATE_RDEV(mddev,rdev,rtmp)
rdev->saved_raid_disk = -1;
mddev->recovery = 0;
/* flag recovery needed just to double check */
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
goto unlock;
}
if (mddev->recovery)
/* probably just the RECOVERY_NEEDED flag */
mddev->recovery = 0;
/* no recovery is running.
* remove any failed drives, then
* add spares if possible.
* Spare are also removed and re-added, to allow
* the personality to fail the re-add.
*/
ITERATE_RDEV(mddev,rdev,rtmp)
if (rdev->raid_disk >= 0 &&
(rdev->faulty || ! rdev->in_sync) &&
atomic_read(&rdev->nr_pending)==0) {
if (mddev->pers->hot_remove_disk(mddev, rdev->raid_disk)==0)
rdev->raid_disk = -1;
}
if (mddev->degraded) {
ITERATE_RDEV(mddev,rdev,rtmp)
if (rdev->raid_disk < 0
&& !rdev->faulty) {
if (mddev->pers->hot_add_disk(mddev,rdev))
spares++;
else
break;
}
}
if (!spares && (mddev->recovery_cp == MaxSector )) {
/* nothing we can do ... */
goto unlock;
}
if (mddev->pers->sync_request) {
set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
if (!spares)
set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
if (spares && mddev->bitmap && ! mddev->bitmap->file) {
/* We are adding a device or devices to an array
* which has the bitmap stored on all devices.
* So make sure all bitmap pages get written
*/
bitmap_write_all(mddev->bitmap);
}
mddev->sync_thread = md_register_thread(md_do_sync,
mddev,
"%s_resync");
if (!mddev->sync_thread) {
printk(KERN_ERR "%s: could not start resync"
" thread...\n",
mdname(mddev));
/* leave the spares where they are, it shouldn't hurt */
mddev->recovery = 0;
} else {
md_wakeup_thread(mddev->sync_thread);
}
}
unlock:
mddev_unlock(mddev);
}
}
static int md_notify_reboot(struct notifier_block *this,
unsigned long code, void *x)
{
struct list_head *tmp;
mddev_t *mddev;
if ((code == SYS_DOWN) || (code == SYS_HALT) || (code == SYS_POWER_OFF)) {
printk(KERN_INFO "md: stopping all md devices.\n");
ITERATE_MDDEV(mddev,tmp)
if (mddev_trylock(mddev)==0)
do_md_stop (mddev, 1);
/*
* certain more exotic SCSI devices are known to be
* volatile wrt too early system reboots. While the
* right place to handle this issue is the given
* driver, we do want to have a safe RAID driver ...
*/
mdelay(1000*1);
}
return NOTIFY_DONE;
}
static struct notifier_block md_notifier = {
.notifier_call = md_notify_reboot,
.next = NULL,
.priority = INT_MAX, /* before any real devices */
};
static void md_geninit(void)
{
struct proc_dir_entry *p;
dprintk("md: sizeof(mdp_super_t) = %d\n", (int)sizeof(mdp_super_t));
p = create_proc_entry("mdstat", S_IRUGO, NULL);
if (p)
p->proc_fops = &md_seq_fops;
}
static int __init md_init(void)
{
int minor;
printk(KERN_INFO "md: md driver %d.%d.%d MAX_MD_DEVS=%d,"
" MD_SB_DISKS=%d\n",
MD_MAJOR_VERSION, MD_MINOR_VERSION,
MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR,
BITMAP_MINOR);
if (register_blkdev(MAJOR_NR, "md"))
return -1;
if ((mdp_major=register_blkdev(0, "mdp"))<=0) {
unregister_blkdev(MAJOR_NR, "md");
return -1;
}
devfs_mk_dir("md");
blk_register_region(MKDEV(MAJOR_NR, 0), MAX_MD_DEVS, THIS_MODULE,
md_probe, NULL, NULL);
blk_register_region(MKDEV(mdp_major, 0), MAX_MD_DEVS<<MdpMinorShift, THIS_MODULE,
md_probe, NULL, NULL);
for (minor=0; minor < MAX_MD_DEVS; ++minor)
devfs_mk_bdev(MKDEV(MAJOR_NR, minor),
S_IFBLK|S_IRUSR|S_IWUSR,
"md/%d", minor);
for (minor=0; minor < MAX_MD_DEVS; ++minor)
devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
S_IFBLK|S_IRUSR|S_IWUSR,
"md/mdp%d", minor);
register_reboot_notifier(&md_notifier);
raid_table_header = register_sysctl_table(raid_root_table, 1);
md_geninit();
return (0);
}
#ifndef MODULE
/*
* Searches all registered partitions for autorun RAID arrays
* at boot time.
*/
static dev_t detected_devices[128];
static int dev_cnt;
void md_autodetect_dev(dev_t dev)
{
if (dev_cnt >= 0 && dev_cnt < 127)
detected_devices[dev_cnt++] = dev;
}
static void autostart_arrays(int part)
{
mdk_rdev_t *rdev;
int i;
printk(KERN_INFO "md: Autodetecting RAID arrays.\n");
for (i = 0; i < dev_cnt; i++) {
dev_t dev = detected_devices[i];
rdev = md_import_device(dev,0, 0);
if (IS_ERR(rdev))
continue;
if (rdev->faulty) {
MD_BUG();
continue;
}
list_add(&rdev->same_set, &pending_raid_disks);
}
dev_cnt = 0;
autorun_devices(part);
}
#endif
static __exit void md_exit(void)
{
mddev_t *mddev;
struct list_head *tmp;
int i;
blk_unregister_region(MKDEV(MAJOR_NR,0), MAX_MD_DEVS);
blk_unregister_region(MKDEV(mdp_major,0), MAX_MD_DEVS << MdpMinorShift);
for (i=0; i < MAX_MD_DEVS; i++)
devfs_remove("md/%d", i);
for (i=0; i < MAX_MD_DEVS; i++)
devfs_remove("md/d%d", i);
devfs_remove("md");
unregister_blkdev(MAJOR_NR,"md");
unregister_blkdev(mdp_major, "mdp");
unregister_reboot_notifier(&md_notifier);
unregister_sysctl_table(raid_table_header);
remove_proc_entry("mdstat", NULL);
ITERATE_MDDEV(mddev,tmp) {
struct gendisk *disk = mddev->gendisk;
if (!disk)
continue;
export_array(mddev);
del_gendisk(disk);
put_disk(disk);
mddev->gendisk = NULL;
mddev_put(mddev);
}
}
module_init(md_init)
module_exit(md_exit)
EXPORT_SYMBOL(register_md_personality);
EXPORT_SYMBOL(unregister_md_personality);
EXPORT_SYMBOL(md_error);
EXPORT_SYMBOL(md_done_sync);
EXPORT_SYMBOL(md_write_start);
EXPORT_SYMBOL(md_write_end);
EXPORT_SYMBOL(md_register_thread);
EXPORT_SYMBOL(md_unregister_thread);
EXPORT_SYMBOL(md_wakeup_thread);
EXPORT_SYMBOL(md_print_devices);
EXPORT_SYMBOL(md_check_recovery);
MODULE_LICENSE("GPL");
MODULE_ALIAS("md");
MODULE_ALIAS_BLOCKDEV_MAJOR(MD_MAJOR);
