/*
* Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
+ * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
*
* This file is released under the GPL.
*/
#include <linux/buffer_head.h>
#include <linux/mempool.h>
#include <linux/slab.h>
+#include <linux/idr.h>
static const char *_name = DM_NAME;
static unsigned int major = 0;
static unsigned int _major = 0;
-static int realloc_minor_bits(unsigned long requested_minor);
-static void free_minor_bits(void);
-
/*
* One of these is allocated per bio.
*/
request_queue_t *queue;
struct gendisk *disk;
+ void *interface_ptr;
+
/*
* A list of ios that arrived while we were suspended.
*/
return -ENOMEM;
}
- r = realloc_minor_bits(1024);
- if (r < 0) {
- kmem_cache_destroy(_tio_cache);
- kmem_cache_destroy(_io_cache);
- return r;
- }
-
_major = major;
r = register_blkdev(_major, _name);
if (r < 0) {
kmem_cache_destroy(_tio_cache);
kmem_cache_destroy(_io_cache);
- free_minor_bits();
return r;
}
{
kmem_cache_destroy(_tio_cache);
kmem_cache_destroy(_io_cache);
- free_minor_bits();
if (unregister_blkdev(_major, _name) < 0)
DMERR("devfs_unregister_blkdev failed");
DMINFO("cleaned up");
}
-/*
- * We have a lot of init/exit functions, so it seems easier to
- * store them in an array. The disposable macro 'xx'
- * expands a prefix into a pair of function names.
- */
-static struct {
- int (*init) (void);
- void (*exit) (void);
-
-} _inits[] = {
-#define xx(n) {n ## _init, n ## _exit},
- xx(local)
- xx(dm_target)
- xx(dm_linear)
- xx(dm_stripe)
- xx(dm_interface)
-#undef xx
+int (*_inits[])(void) __initdata = {
+ local_init,
+ dm_target_init,
+ dm_linear_init,
+ dm_stripe_init,
+ dm_interface_init,
+};
+
+void (*_exits[])(void) = {
+ local_exit,
+ dm_target_exit,
+ dm_linear_exit,
+ dm_stripe_exit,
+ dm_interface_exit,
};
static int __init dm_init(void)
int r, i;
for (i = 0; i < count; i++) {
- r = _inits[i].init();
+ r = _inits[i]();
if (r)
goto bad;
}
bad:
while (i--)
- _inits[i].exit();
+ _exits[i]();
return r;
}
static void __exit dm_exit(void)
{
- int i = ARRAY_SIZE(_inits);
+ int i = ARRAY_SIZE(_exits);
while (i--)
- _inits[i].exit();
+ _exits[i]();
}
/*
*/
if (ti->split_io) {
sector_t boundary;
- boundary = dm_round_up(offset + 1, ti->split_io) - offset;
-
+ boundary = ((offset + ti->split_io) & ~(ti->split_io - 1))
+ - offset;
if (len > boundary)
len = boundary;
}
return 0;
}
+static int dm_flush_all(request_queue_t *q, struct gendisk *disk,
+ sector_t *error_sector)
+{
+ struct mapped_device *md = q->queuedata;
+ struct dm_table *map = dm_get_table(md);
+ int ret = -ENXIO;
+
+ if (map) {
+ ret = dm_table_flush_all(md->map);
+ dm_table_put(map);
+ }
+
+ return ret;
+}
+
static void dm_unplug_all(request_queue_t *q)
{
struct mapped_device *md = q->queuedata;
}
/*-----------------------------------------------------------------
- * A bitset is used to keep track of allocated minor numbers.
+ * An IDR is used to keep track of allocated minor numbers.
*---------------------------------------------------------------*/
static DECLARE_MUTEX(_minor_lock);
-static unsigned long *_minor_bits = NULL;
-static unsigned long _max_minors = 0;
-
-#define MINORS_SIZE(minors) ((minors / BITS_PER_LONG) * sizeof(unsigned long))
-
-static int realloc_minor_bits(unsigned long requested_minor)
-{
- unsigned long max_minors;
- unsigned long *minor_bits, *tmp;
-
- if (requested_minor < _max_minors)
- return -EINVAL;
-
- /* Round up the requested minor to the next power-of-2. */
- max_minors = 1 << fls(requested_minor - 1);
- if (max_minors > (1 << MINORBITS))
- return -EINVAL;
-
- minor_bits = kmalloc(MINORS_SIZE(max_minors), GFP_KERNEL);
- if (!minor_bits)
- return -ENOMEM;
- memset(minor_bits, 0, MINORS_SIZE(max_minors));
-
- /* Copy the existing bit-set to the new one. */
- if (_minor_bits)
- memcpy(minor_bits, _minor_bits, MINORS_SIZE(_max_minors));
-
- tmp = _minor_bits;
- _minor_bits = minor_bits;
- _max_minors = max_minors;
- if (tmp)
- kfree(tmp);
-
- return 0;
-}
-
-static void free_minor_bits(void)
-{
- down(&_minor_lock);
- kfree(_minor_bits);
- _minor_bits = NULL;
- _max_minors = 0;
- up(&_minor_lock);
-}
+static DEFINE_IDR(_minor_idr);
static void free_minor(unsigned int minor)
{
down(&_minor_lock);
- if (minor < _max_minors)
- clear_bit(minor, _minor_bits);
+ idr_remove(&_minor_idr, minor);
up(&_minor_lock);
}
/*
* See if the device with a specific minor # is free.
*/
-static int specific_minor(unsigned int minor)
+static int specific_minor(struct mapped_device *md, unsigned int minor)
{
- int r = 0;
+ int r, m;
- if (minor > (1 << MINORBITS))
+ if (minor >= (1 << MINORBITS))
return -EINVAL;
down(&_minor_lock);
- if (minor >= _max_minors) {
- r = realloc_minor_bits(minor);
- if (r) {
- up(&_minor_lock);
- return r;
- }
+
+ if (idr_find(&_minor_idr, minor)) {
+ r = -EBUSY;
+ goto out;
+ }
+
+ r = idr_pre_get(&_minor_idr, GFP_KERNEL);
+ if (!r) {
+ r = -ENOMEM;
+ goto out;
}
- if (test_and_set_bit(minor, _minor_bits))
+ r = idr_get_new_above(&_minor_idr, md, minor, &m);
+ if (r) {
+ goto out;
+ }
+
+ if (m != minor) {
+ idr_remove(&_minor_idr, m);
r = -EBUSY;
- up(&_minor_lock);
+ goto out;
+ }
+out:
+ up(&_minor_lock);
return r;
}
-static int next_free_minor(unsigned int *minor)
+static int next_free_minor(struct mapped_device *md, unsigned int *minor)
{
int r;
unsigned int m;
down(&_minor_lock);
- m = find_first_zero_bit(_minor_bits, _max_minors);
- if (m >= _max_minors) {
- r = realloc_minor_bits(_max_minors * 2);
- if (r) {
- up(&_minor_lock);
- return r;
- }
- m = find_first_zero_bit(_minor_bits, _max_minors);
+
+ r = idr_pre_get(&_minor_idr, GFP_KERNEL);
+ if (!r) {
+ r = -ENOMEM;
+ goto out;
+ }
+
+ r = idr_get_new(&_minor_idr, md, &m);
+ if (r) {
+ goto out;
+ }
+
+ if (m >= (1 << MINORBITS)) {
+ idr_remove(&_minor_idr, m);
+ r = -ENOSPC;
+ goto out;
}
- set_bit(m, _minor_bits);
*minor = m;
- up(&_minor_lock);
- return 0;
+out:
+ up(&_minor_lock);
+ return r;
}
static struct block_device_operations dm_blk_dops;
}
/* get a minor number for the dev */
- r = persistent ? specific_minor(minor) : next_free_minor(&minor);
+ r = persistent ? specific_minor(md, minor) : next_free_minor(md, &minor);
if (r < 0)
goto bad1;
md->queue->backing_dev_info.congested_data = md;
blk_queue_make_request(md->queue, dm_request);
md->queue->unplug_fn = dm_unplug_all;
+ md->queue->issue_flush_fn = dm_flush_all;
md->io_pool = mempool_create(MIN_IOS, mempool_alloc_slab,
mempool_free_slab, _io_cache);
{
struct mapped_device *md = (struct mapped_device *) context;
- atomic_inc(&md->event_nr);;
+ atomic_inc(&md->event_nr);
wake_up(&md->eventq);
}
return create_aux(minor, 1, result);
}
+void *dm_get_mdptr(dev_t dev)
+{
+ struct mapped_device *md;
+ void *mdptr = NULL;
+ unsigned minor = MINOR(dev);
+
+ if (MAJOR(dev) != _major || minor >= (1 << MINORBITS))
+ return NULL;
+
+ down(&_minor_lock);
+
+ md = idr_find(&_minor_idr, minor);
+
+ if (md && (dm_disk(md)->first_minor == minor))
+ mdptr = md->interface_ptr;
+
+ up(&_minor_lock);
+
+ return mdptr;
+}
+
+void dm_set_mdptr(struct mapped_device *md, void *ptr)
+{
+ md->interface_ptr = ptr;
+}
+
void dm_get(struct mapped_device *md)
{
atomic_inc(&md->holders);
struct dm_table *map = dm_get_table(md);
if (atomic_dec_and_test(&md->holders)) {
- if (!test_bit(DMF_SUSPENDED, &md->flags) && map)
- dm_table_suspend_targets(map);
+ if (!test_bit(DMF_SUSPENDED, &md->flags) && map) {
+ dm_table_presuspend_targets(map);
+ dm_table_postsuspend_targets(map);
+ }
__unbind(md);
free_dev(md);
}
return -EINVAL;
}
+ map = dm_get_table(md);
+ if (map)
+ dm_table_presuspend_targets(map);
__lock_fs(md);
+
up_read(&md->lock);
/*
up_write(&md->lock);
/* unplug */
- map = dm_get_table(md);
if (map) {
dm_table_unplug_all(map);
dm_table_put(map);
map = dm_get_table(md);
if (map)
- dm_table_suspend_targets(map);
+ dm_table_postsuspend_targets(map);
dm_table_put(map);
up_write(&md->lock);
module_param(major, uint, 0);
MODULE_PARM_DESC(major, "The major number of the device mapper");
MODULE_DESCRIPTION(DM_NAME " driver");
-MODULE_AUTHOR("Joe Thornber <thornber@sistina.com>");
+MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
MODULE_LICENSE("GPL");
git://git.onelab.eu / linux-2.6.git / blobdiff