[net-next-2.6.git] / fs / partitions / check.c

/*
 *  fs/partitions/check.c
 *
 *  Code extracted from drivers/block/genhd.c
 *  Copyright (C) 1991-1998  Linus Torvalds
 *  Re-organised Feb 1998 Russell King
 *
 *  We now have independent partition support from the
 *  block drivers, which allows all the partition code to
 *  be grouped in one location, and it to be mostly self
 *  contained.
 *
 *  Added needed MAJORS for new pairs, {hdi,hdj}, {hdk,hdl}
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/kmod.h>
#include <linux/ctype.h>
#include <linux/devfs_fs_kernel.h>

#include "check.h"
#include "devfs.h"

#include "acorn.h"
#include "amiga.h"
#include "atari.h"
#include "ldm.h"
#include "mac.h"
#include "msdos.h"
#include "osf.h"
#include "sgi.h"
#include "sun.h"
#include "ibm.h"
#include "ultrix.h"
#include "efi.h"

#ifdef CONFIG_BLK_DEV_MD
extern void md_autodetect_dev(dev_t dev);
#endif

int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/

static int (*check_part[])(struct parsed_partitions *, struct block_device *) = {
	/*
	 * Probe partition formats with tables at disk address 0
	 * that also have an ADFS boot block at 0xdc0.
	 */
#ifdef CONFIG_ACORN_PARTITION_ICS
	adfspart_check_ICS,
#endif
#ifdef CONFIG_ACORN_PARTITION_POWERTEC
	adfspart_check_POWERTEC,
#endif
#ifdef CONFIG_ACORN_PARTITION_EESOX
	adfspart_check_EESOX,
#endif

	/*
	 * Now move on to formats that only have partition info at
	 * disk address 0xdc0.  Since these may also have stale
	 * PC/BIOS partition tables, they need to come before
	 * the msdos entry.
	 */
#ifdef CONFIG_ACORN_PARTITION_CUMANA
	adfspart_check_CUMANA,
#endif
#ifdef CONFIG_ACORN_PARTITION_ADFS
	adfspart_check_ADFS,
#endif

#ifdef CONFIG_EFI_PARTITION
	efi_partition,		/* this must come before msdos */
#endif
#ifdef CONFIG_SGI_PARTITION
	sgi_partition,
#endif
#ifdef CONFIG_LDM_PARTITION
	ldm_partition,		/* this must come before msdos */
#endif
#ifdef CONFIG_MSDOS_PARTITION
	msdos_partition,
#endif
#ifdef CONFIG_OSF_PARTITION
	osf_partition,
#endif
#ifdef CONFIG_SUN_PARTITION
	sun_partition,
#endif
#ifdef CONFIG_AMIGA_PARTITION
	amiga_partition,
#endif
#ifdef CONFIG_ATARI_PARTITION
	atari_partition,
#endif
#ifdef CONFIG_MAC_PARTITION
	mac_partition,
#endif
#ifdef CONFIG_ULTRIX_PARTITION
	ultrix_partition,
#endif
#ifdef CONFIG_IBM_PARTITION
	ibm_partition,
#endif
	NULL
};
 
/*
 * disk_name() is used by partition check code and the genhd driver.
 * It formats the devicename of the indicated disk into
 * the supplied buffer (of size at least 32), and returns
 * a pointer to that same buffer (for convenience).
 */

char *disk_name(struct gendisk *hd, int part, char *buf)
{
	if (!part)
		snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
	else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
		snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, part);
	else
		snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, part);

	return buf;
}

const char *bdevname(struct block_device *bdev, char *buf)
{
	int part = MINOR(bdev->bd_dev) - bdev->bd_disk->first_minor;
	return disk_name(bdev->bd_disk, part, buf);
}

EXPORT_SYMBOL(bdevname);

/*
 * There's very little reason to use this, you should really
 * have a struct block_device just about everywhere and use
 * bdevname() instead.
 */
const char *__bdevname(dev_t dev, char *buffer)
{
	scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
				MAJOR(dev), MINOR(dev));
	return buffer;
}

EXPORT_SYMBOL(__bdevname);

static struct parsed_partitions *
check_partition(struct gendisk *hd, struct block_device *bdev)
{
	struct parsed_partitions *state;
	int i, res;

	state = kmalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
	if (!state)
		return NULL;

#ifdef CONFIG_DEVFS_FS
	if (hd->devfs_name[0] != '\0') {
		printk(KERN_INFO " /dev/%s:", hd->devfs_name);
		sprintf(state->name, "p");
	}
#endif
	else {
		disk_name(hd, 0, state->name);
		printk(KERN_INFO " %s:", state->name);
		if (isdigit(state->name[strlen(state->name)-1]))
			sprintf(state->name, "p");
	}
	state->limit = hd->minors;
	i = res = 0;
	while (!res && check_part[i]) {
		memset(&state->parts, 0, sizeof(state->parts));
		res = check_part[i++](state, bdev);
	}
	if (res > 0)
		return state;
	if (!res)
		printk(" unknown partition table\n");
	else if (warn_no_part)
		printk(" unable to read partition table\n");
	kfree(state);
	return NULL;
}

/*
 * sysfs bindings for partitions
 */

struct part_attribute {
	struct attribute attr;
	ssize_t (*show)(struct hd_struct *,char *);
};

static ssize_t 
part_attr_show(struct kobject * kobj, struct attribute * attr, char * page)
{
	struct hd_struct * p = container_of(kobj,struct hd_struct,kobj);
	struct part_attribute * part_attr = container_of(attr,struct part_attribute,attr);
	ssize_t ret = 0;
	if (part_attr->show)
		ret = part_attr->show(p,page);
	return ret;
}

static struct sysfs_ops part_sysfs_ops = {
	.show	=	part_attr_show,
};

static ssize_t part_dev_read(struct hd_struct * p, char *page)
{
	struct gendisk *disk = container_of(p->kobj.parent,struct gendisk,kobj);
	dev_t dev = MKDEV(disk->major, disk->first_minor + p->partno); 
	return print_dev_t(page, dev);
}
static ssize_t part_start_read(struct hd_struct * p, char *page)
{
	return sprintf(page, "%llu\n",(unsigned long long)p->start_sect);
}
static ssize_t part_size_read(struct hd_struct * p, char *page)
{
	return sprintf(page, "%llu\n",(unsigned long long)p->nr_sects);
}
static ssize_t part_stat_read(struct hd_struct * p, char *page)
{
	return sprintf(page, "%8u %8llu %8u %8llu\n",
		       p->reads, (unsigned long long)p->read_sectors,
		       p->writes, (unsigned long long)p->write_sectors);
}
static struct part_attribute part_attr_dev = {
	.attr = {.name = "dev", .mode = S_IRUGO },
	.show	= part_dev_read
};
static struct part_attribute part_attr_start = {
	.attr = {.name = "start", .mode = S_IRUGO },
	.show	= part_start_read
};
static struct part_attribute part_attr_size = {
	.attr = {.name = "size", .mode = S_IRUGO },
	.show	= part_size_read
};
static struct part_attribute part_attr_stat = {
	.attr = {.name = "stat", .mode = S_IRUGO },
	.show	= part_stat_read
};

static struct attribute * default_attrs[] = {
	&part_attr_dev.attr,
	&part_attr_start.attr,
	&part_attr_size.attr,
	&part_attr_stat.attr,
	NULL,
};

extern struct subsystem block_subsys;

static void part_release(struct kobject *kobj)
{
	struct hd_struct * p = container_of(kobj,struct hd_struct,kobj);
	kfree(p);
}

struct kobj_type ktype_part = {
	.release	= part_release,
	.default_attrs	= default_attrs,
	.sysfs_ops	= &part_sysfs_ops,
};

void delete_partition(struct gendisk *disk, int part)
{
	struct hd_struct *p = disk->part[part-1];
	if (!p)
		return;
	if (!p->nr_sects)
		return;
	disk->part[part-1] = NULL;
	p->start_sect = 0;
	p->nr_sects = 0;
	p->reads = p->writes = p->read_sectors = p->write_sectors = 0;
	devfs_remove("%s/part%d", disk->devfs_name, part);
	kobject_unregister(&p->kobj);
}

void add_partition(struct gendisk *disk, int part, sector_t start, sector_t len)
{
	struct hd_struct *p;

	p = kmalloc(sizeof(*p), GFP_KERNEL);
	if (!p)
		return;
	
	memset(p, 0, sizeof(*p));
	p->start_sect = start;
	p->nr_sects = len;
	p->partno = part;

	devfs_mk_bdev(MKDEV(disk->major, disk->first_minor + part),
			S_IFBLK|S_IRUSR|S_IWUSR,
			"%s/part%d", disk->devfs_name, part);

	if (isdigit(disk->kobj.name[strlen(disk->kobj.name)-1]))
		snprintf(p->kobj.name,KOBJ_NAME_LEN,"%sp%d",disk->kobj.name,part);
	else
		snprintf(p->kobj.name,KOBJ_NAME_LEN,"%s%d",disk->kobj.name,part);
	p->kobj.parent = &disk->kobj;
	p->kobj.ktype = &ktype_part;
	kobject_register(&p->kobj);
	disk->part[part-1] = p;
}

static void disk_sysfs_symlinks(struct gendisk *disk)
{
	struct device *target = get_device(disk->driverfs_dev);
	if (target) {
		sysfs_create_link(&disk->kobj,&target->kobj,"device");
		sysfs_create_link(&target->kobj,&disk->kobj,"block");
	}
}

/* Not exported, helper to add_disk(). */
void register_disk(struct gendisk *disk)
{
	struct block_device *bdev;
	char *s;
	int err;

	strlcpy(disk->kobj.name,disk->disk_name,KOBJ_NAME_LEN);
	/* ewww... some of these buggers have / in name... */
	s = strchr(disk->kobj.name, '/');
	if (s)
		*s = '!';
	if ((err = kobject_add(&disk->kobj)))
		return;
	disk_sysfs_symlinks(disk);
	kobject_hotplug(&disk->kobj, KOBJ_ADD);

	/* No minors to use for partitions */
	if (disk->minors == 1) {
		if (disk->devfs_name[0] != '\0')
			devfs_add_disk(disk);
		return;
	}

	/* always add handle for the whole disk */
	devfs_add_partitioned(disk);

	/* No such device (e.g., media were just removed) */
	if (!get_capacity(disk))
		return;

	bdev = bdget_disk(disk, 0);
	if (!bdev)
		return;

	bdev->bd_invalidated = 1;
	if (blkdev_get(bdev, FMODE_READ, 0) < 0)
		return;
	blkdev_put(bdev);
}

int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
{
	struct parsed_partitions *state;
	int p, res;

	if (bdev->bd_part_count)
		return -EBUSY;
	res = invalidate_partition(disk, 0);
	if (res)
		return res;
	bdev->bd_invalidated = 0;
	for (p = 1; p < disk->minors; p++)
		delete_partition(disk, p);
	if (disk->fops->revalidate_disk)
		disk->fops->revalidate_disk(disk);
	if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
		return 0;
	for (p = 1; p < state->limit; p++) {
		sector_t size = state->parts[p].size;
		sector_t from = state->parts[p].from;
		if (!size)
			continue;
		add_partition(disk, p, from, size);
#ifdef CONFIG_BLK_DEV_MD
		if (state->parts[p].flags)
			md_autodetect_dev(bdev->bd_dev+p);
#endif
	}
	kfree(state);
	return 0;
}

unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
{
	struct address_space *mapping = bdev->bd_inode->i_mapping;
	struct page *page;

	page = read_cache_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
			(filler_t *)mapping->a_ops->readpage, NULL);
	if (!IS_ERR(page)) {
		wait_on_page_locked(page);
		if (!PageUptodate(page))
			goto fail;
		if (PageError(page))
			goto fail;
		p->v = page;
		return (unsigned char *)page_address(page) +  ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
fail:
		page_cache_release(page);
	}
	p->v = NULL;
	return NULL;
}

EXPORT_SYMBOL(read_dev_sector);

void del_gendisk(struct gendisk *disk)
{
	int p;

	/* invalidate stuff */
	for (p = disk->minors - 1; p > 0; p--) {
		invalidate_partition(disk, p);
		delete_partition(disk, p);
	}
	invalidate_partition(disk, 0);
	disk->capacity = 0;
	disk->flags &= ~GENHD_FL_UP;
	unlink_gendisk(disk);
	disk_stat_set_all(disk, 0);
	disk->stamp = disk->stamp_idle = 0;

	devfs_remove_disk(disk);

	if (disk->driverfs_dev) {
		sysfs_remove_link(&disk->kobj, "device");
		sysfs_remove_link(&disk->driverfs_dev->kobj, "block");
		put_device(disk->driverfs_dev);
	}
	kobject_hotplug(&disk->kobj, KOBJ_REMOVE);
	kobject_del(&disk->kobj);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* fs/partitions/check.c
	3	*
	4	* Code extracted from drivers/block/genhd.c
	5	* Copyright (C) 1991-1998 Linus Torvalds
	6	* Re-organised Feb 1998 Russell King
	7	*
	8	* We now have independent partition support from the
	9	* block drivers, which allows all the partition code to
	10	* be grouped in one location, and it to be mostly self
	11	* contained.
	12	*
	13	* Added needed MAJORS for new pairs, {hdi,hdj}, {hdk,hdl}
	14	*/
	15
	16	#include <linux/init.h>
	17	#include <linux/module.h>
	18	#include <linux/fs.h>
	19	#include <linux/kmod.h>
	20	#include <linux/ctype.h>
	21	#include <linux/devfs_fs_kernel.h>
	22
	23	#include "check.h"
	24	#include "devfs.h"
	25
	26	#include "acorn.h"
	27	#include "amiga.h"
	28	#include "atari.h"
	29	#include "ldm.h"
	30	#include "mac.h"
	31	#include "msdos.h"
	32	#include "osf.h"
	33	#include "sgi.h"
	34	#include "sun.h"
	35	#include "ibm.h"
	36	#include "ultrix.h"
	37	#include "efi.h"
	38
	39	#ifdef CONFIG_BLK_DEV_MD
	40	extern void md_autodetect_dev(dev_t dev);
	41	#endif
	42
	43	int warn_no_part = 1; /This is ugly: should make genhd removable media aware/
	44
	45	static int (check_part[])(struct parsed_partitions , struct block_device *) = {
	46	/*
	47	* Probe partition formats with tables at disk address 0
	48	* that also have an ADFS boot block at 0xdc0.
	49	*/
	50	#ifdef CONFIG_ACORN_PARTITION_ICS
	51	adfspart_check_ICS,
	52	#endif
	53	#ifdef CONFIG_ACORN_PARTITION_POWERTEC
	54	adfspart_check_POWERTEC,
	55	#endif
	56	#ifdef CONFIG_ACORN_PARTITION_EESOX
	57	adfspart_check_EESOX,
	58	#endif
	59
	60	/*
	61	* Now move on to formats that only have partition info at
	62	* disk address 0xdc0. Since these may also have stale
	63	* PC/BIOS partition tables, they need to come before
	64	* the msdos entry.
65	*/
66	#ifdef CONFIG_ACORN_PARTITION_CUMANA
67	adfspart_check_CUMANA,
68	#endif
69	#ifdef CONFIG_ACORN_PARTITION_ADFS
70	adfspart_check_ADFS,
71	#endif
72
73	#ifdef CONFIG_EFI_PARTITION
74	efi_partition, /* this must come before msdos */
75	#endif
76	#ifdef CONFIG_SGI_PARTITION
77	sgi_partition,
78	#endif
79	#ifdef CONFIG_LDM_PARTITION
80	ldm_partition, /* this must come before msdos */
81	#endif
1da177e4 LT	82	#ifdef CONFIG_MSDOS_PARTITION
	83	msdos_partition,
	84	#endif
	85	#ifdef CONFIG_OSF_PARTITION
	86	osf_partition,
	87	#endif
	88	#ifdef CONFIG_SUN_PARTITION
	89	sun_partition,
	90	#endif
	91	#ifdef CONFIG_AMIGA_PARTITION
	92	amiga_partition,
	93	#endif
	94	#ifdef CONFIG_ATARI_PARTITION
	95	atari_partition,
	96	#endif
	97	#ifdef CONFIG_MAC_PARTITION
	98	mac_partition,
	99	#endif
	100	#ifdef CONFIG_ULTRIX_PARTITION
	101	ultrix_partition,
	102	#endif
	103	#ifdef CONFIG_IBM_PARTITION
	104	ibm_partition,
	105	#endif
	106	NULL
	107	};
	108
	109	/*
	110	* disk_name() is used by partition check code and the genhd driver.
	111	* It formats the devicename of the indicated disk into
	112	* the supplied buffer (of size at least 32), and returns
	113	* a pointer to that same buffer (for convenience).
	114	*/
	115
	116	char disk_name(struct gendisk hd, int part, char *buf)
	117	{
	118	if (!part)
	119	snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
	120	else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
	121	snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, part);
	122	else
	123	snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, part);
	124
	125	return buf;
	126	}
	127
	128	const char bdevname(struct block_device bdev, char *buf)
	129	{
	130	int part = MINOR(bdev->bd_dev) - bdev->bd_disk->first_minor;
	131	return disk_name(bdev->bd_disk, part, buf);
	132	}
	133
	134	EXPORT_SYMBOL(bdevname);
	135
	136	/*
	137	* There's very little reason to use this, you should really
	138	* have a struct block_device just about everywhere and use
	139	* bdevname() instead.
	140	*/
	141	const char __bdevname(dev_t dev, char buffer)
	142	{
	143	scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
	144	MAJOR(dev), MINOR(dev));
	145	return buffer;
146	}
147
148	EXPORT_SYMBOL(__bdevname);
149
150	static struct parsed_partitions *
151	check_partition(struct gendisk hd, struct block_device bdev)
152	{
153	struct parsed_partitions *state;
154	int i, res;
155
156	state = kmalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
157	if (!state)
158	return NULL;
159
160	#ifdef CONFIG_DEVFS_FS
161	if (hd->devfs_name[0] != '\0') {
162	printk(KERN_INFO " /dev/%s:", hd->devfs_name);
163	sprintf(state->name, "p");
164	}
165	#endif
166	else {
167	disk_name(hd, 0, state->name);
168	printk(KERN_INFO " %s:", state->name);
169	if (isdigit(state->name[strlen(state->name)-1]))
170	sprintf(state->name, "p");
171	}
172	state->limit = hd->minors;
173	i = res = 0;
174	while (!res && check_part[i]) {
175	memset(&state->parts, 0, sizeof(state->parts));
176	res = check_part[i++](state, bdev);
177	}
178	if (res > 0)
179	return state;
180	if (!res)
181	printk(" unknown partition table\n");
182	else if (warn_no_part)
183	printk(" unable to read partition table\n");
184	kfree(state);
185	return NULL;
186	}
187
188	/*
189	* sysfs bindings for partitions
190	*/
191
192	struct part_attribute {
193	struct attribute attr;
194	ssize_t (show)(struct hd_struct ,char *);
195	};
196
197	static ssize_t
198	part_attr_show(struct kobject * kobj, struct attribute * attr, char * page)
199	{
200	struct hd_struct * p = container_of(kobj,struct hd_struct,kobj);
201	struct part_attribute * part_attr = container_of(attr,struct part_attribute,attr);
202	ssize_t ret = 0;
203	if (part_attr->show)
204	ret = part_attr->show(p,page);
205	return ret;
206	}
207
208	static struct sysfs_ops part_sysfs_ops = {
209	.show = part_attr_show,
210	};
211
212	static ssize_t part_dev_read(struct hd_struct * p, char *page)
213	{
214	struct gendisk *disk = container_of(p->kobj.parent,struct gendisk,kobj);
215	dev_t dev = MKDEV(disk->major, disk->first_minor + p->partno);
216	return print_dev_t(page, dev);
217	}
218	static ssize_t part_start_read(struct hd_struct * p, char *page)
219	{
220	return sprintf(page, "%llu\n",(unsigned long long)p->start_sect);
221	}
222	static ssize_t part_size_read(struct hd_struct * p, char *page)
223	{
224	return sprintf(page, "%llu\n",(unsigned long long)p->nr_sects);
225	}
226	static ssize_t part_stat_read(struct hd_struct * p, char *page)
227	{
228	return sprintf(page, "%8u %8llu %8u %8llu\n",
229	p->reads, (unsigned long long)p->read_sectors,
230	p->writes, (unsigned long long)p->write_sectors);
231	}
232	static struct part_attribute part_attr_dev = {
233	.attr = {.name = "dev", .mode = S_IRUGO },
234	.show = part_dev_read
235	};
236	static struct part_attribute part_attr_start = {
237	.attr = {.name = "start", .mode = S_IRUGO },
238	.show = part_start_read
239	};
240	static struct part_attribute part_attr_size = {
241	.attr = {.name = "size", .mode = S_IRUGO },
242	.show = part_size_read
243	};
244	static struct part_attribute part_attr_stat = {
245	.attr = {.name = "stat", .mode = S_IRUGO },
246	.show = part_stat_read
247	};
248
249	static struct attribute * default_attrs[] = {
250	&part_attr_dev.attr,
251	&part_attr_start.attr,
252	&part_attr_size.attr,
253	&part_attr_stat.attr,
254	NULL,
255	};
256
257	extern struct subsystem block_subsys;
258
259	static void part_release(struct kobject *kobj)
260	{
261	struct hd_struct * p = container_of(kobj,struct hd_struct,kobj);
262	kfree(p);
263	}
264
265	struct kobj_type ktype_part = {
266	.release = part_release,
267	.default_attrs = default_attrs,
268	.sysfs_ops = &part_sysfs_ops,
269	};
270
271	void delete_partition(struct gendisk *disk, int part)
272	{
273	struct hd_struct *p = disk->part[part-1];
274	if (!p)
275	return;
276	if (!p->nr_sects)
277	return;
278	disk->part[part-1] = NULL;
279	p->start_sect = 0;
280	p->nr_sects = 0;
281	p->reads = p->writes = p->read_sectors = p->write_sectors = 0;
282	devfs_remove("%s/part%d", disk->devfs_name, part);
283	kobject_unregister(&p->kobj);
284	}
285
286	void add_partition(struct gendisk *disk, int part, sector_t start, sector_t len)
287	{
288	struct hd_struct *p;
289
290	p = kmalloc(sizeof(*p), GFP_KERNEL);
291	if (!p)
292	return;
293
294	memset(p, 0, sizeof(*p));
295	p->start_sect = start;
296	p->nr_sects = len;
297	p->partno = part;
298
299	devfs_mk_bdev(MKDEV(disk->major, disk->first_minor + part),
300	S_IFBLK\|S_IRUSR\|S_IWUSR,
301	"%s/part%d", disk->devfs_name, part);
302
303	if (isdigit(disk->kobj.name[strlen(disk->kobj.name)-1]))
304	snprintf(p->kobj.name,KOBJ_NAME_LEN,"%sp%d",disk->kobj.name,part);
305	else
306	snprintf(p->kobj.name,KOBJ_NAME_LEN,"%s%d",disk->kobj.name,part);
307	p->kobj.parent = &disk->kobj;
308	p->kobj.ktype = &ktype_part;
309	kobject_register(&p->kobj);
310	disk->part[part-1] = p;
311	}
312
313	static void disk_sysfs_symlinks(struct gendisk *disk)
314	{
315	struct device *target = get_device(disk->driverfs_dev);
316	if (target) {
317	sysfs_create_link(&disk->kobj,&target->kobj,"device");
318	sysfs_create_link(&target->kobj,&disk->kobj,"block");
319	}
320	}
321
322	/* Not exported, helper to add_disk(). */
323	void register_disk(struct gendisk *disk)
324	{
325	struct block_device *bdev;
326	char *s;
327	int err;
328
329	strlcpy(disk->kobj.name,disk->disk_name,KOBJ_NAME_LEN);
330	/* ewww... some of these buggers have / in name... */
331	s = strchr(disk->kobj.name, '/');
332	if (s)
333	*s = '!';
334	if ((err = kobject_add(&disk->kobj)))
335	return;
336	disk_sysfs_symlinks(disk);
b41148c0	337	kobject_hotplug(&disk->kobj, KOBJ_ADD);
1da177e4 LT	338
	339	/* No minors to use for partitions */
	340	if (disk->minors == 1) {
	341	if (disk->devfs_name[0] != '\0')
	342	devfs_add_disk(disk);
	343	return;
	344	}
	345
	346	/* always add handle for the whole disk */
	347	devfs_add_partitioned(disk);
	348
	349	/* No such device (e.g., media were just removed) */
	350	if (!get_capacity(disk))
	351	return;
	352
	353	bdev = bdget_disk(disk, 0);
	354	if (!bdev)
	355	return;
	356
	357	bdev->bd_invalidated = 1;
	358	if (blkdev_get(bdev, FMODE_READ, 0) < 0)
	359	return;
	360	blkdev_put(bdev);
	361	}
	362
	363	int rescan_partitions(struct gendisk disk, struct block_device bdev)
	364	{
	365	struct parsed_partitions *state;
	366	int p, res;
	367
	368	if (bdev->bd_part_count)
	369	return -EBUSY;
	370	res = invalidate_partition(disk, 0);
	371	if (res)
	372	return res;
	373	bdev->bd_invalidated = 0;
	374	for (p = 1; p < disk->minors; p++)
	375	delete_partition(disk, p);
	376	if (disk->fops->revalidate_disk)
	377	disk->fops->revalidate_disk(disk);
	378	if (!get_capacity(disk) \|\| !(state = check_partition(disk, bdev)))
	379	return 0;
	380	for (p = 1; p < state->limit; p++) {
	381	sector_t size = state->parts[p].size;
	382	sector_t from = state->parts[p].from;
	383	if (!size)
	384	continue;
	385	add_partition(disk, p, from, size);
	386	#ifdef CONFIG_BLK_DEV_MD
	387	if (state->parts[p].flags)
	388	md_autodetect_dev(bdev->bd_dev+p);
	389	#endif
	390	}
	391	kfree(state);
	392	return 0;
	393	}
	394
	395	unsigned char read_dev_sector(struct block_device bdev, sector_t n, Sector *p)
	396	{
	397	struct address_space *mapping = bdev->bd_inode->i_mapping;
	398	struct page *page;
	399
	400	page = read_cache_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
	401	(filler_t *)mapping->a_ops->readpage, NULL);
402	if (!IS_ERR(page)) {
403	wait_on_page_locked(page);
404	if (!PageUptodate(page))
405	goto fail;
406	if (PageError(page))
407	goto fail;
408	p->v = page;
409	return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
410	fail:
411	page_cache_release(page);
412	}
413	p->v = NULL;
414	return NULL;
415	}
416
417	EXPORT_SYMBOL(read_dev_sector);
418
419	void del_gendisk(struct gendisk *disk)
420	{
421	int p;
422
423	/* invalidate stuff */
424	for (p = disk->minors - 1; p > 0; p--) {
425	invalidate_partition(disk, p);
426	delete_partition(disk, p);
427	}
428	invalidate_partition(disk, 0);
429	disk->capacity = 0;
430	disk->flags &= ~GENHD_FL_UP;
431	unlink_gendisk(disk);
432	disk_stat_set_all(disk, 0);
433	disk->stamp = disk->stamp_idle = 0;
434
435	devfs_remove_disk(disk);
436
437	if (disk->driverfs_dev) {
438	sysfs_remove_link(&disk->kobj, "device");
439	sysfs_remove_link(&disk->driverfs_dev->kobj, "block");
440	put_device(disk->driverfs_dev);
441	}
b41148c0	442	kobject_hotplug(&disk->kobj, KOBJ_REMOVE);
1da177e4 LT	443	kobject_del(&disk->kobj);
1da177e4 LT	444	}