[GitHub/mt8127/android_kernel_alcatel_ttab.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 "check.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"
#include "karma.h"
#include "sysv68.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
#ifdef CONFIG_KARMA_PARTITION
	karma_partition,
#endif
#ifdef CONFIG_SYSV68_PARTITION
	sysv68_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, err;

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

	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 = err = 0;
	while (!res && check_part[i]) {
		memset(&state->parts, 0, sizeof(state->parts));
		res = check_part[i++](state, bdev);
		if (res < 0) {
			/* We have hit an I/O error which we don't report now.
		 	* But record it, and let the others do their job.
		 	*/
			err = res;
			res = 0;
		}

	}
	if (res > 0)
		return state;
	if (err)
	/* The partition is unrecognized. So report I/O errors if there were any */
		res = err;
	if (!res)
		printk(" unknown partition table\n");
	else if (warn_no_part)
		printk(" unable to read partition table\n");
	kfree(state);
	return ERR_PTR(res);
}

static ssize_t part_start_show(struct device *dev,
			       struct device_attribute *attr, char *buf)
{
	struct hd_struct *p = dev_to_part(dev);

	return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
}

static ssize_t part_size_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct hd_struct *p = dev_to_part(dev);
	return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
}

static ssize_t part_stat_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct hd_struct *p = dev_to_part(dev);

	return sprintf(buf, "%8u %8llu %8u %8llu\n",
		       p->ios[0], (unsigned long long)p->sectors[0],
		       p->ios[1], (unsigned long long)p->sectors[1]);
}

#ifdef CONFIG_FAIL_MAKE_REQUEST
static ssize_t part_fail_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct hd_struct *p = dev_to_part(dev);

	return sprintf(buf, "%d\n", p->make_it_fail);
}

static ssize_t part_fail_store(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	struct hd_struct *p = dev_to_part(dev);
	int i;

	if (count > 0 && sscanf(buf, "%d", &i) > 0)
		p->make_it_fail = (i == 0) ? 0 : 1;

	return count;
}
#endif

static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
#ifdef CONFIG_FAIL_MAKE_REQUEST
static struct device_attribute dev_attr_fail =
	__ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
#endif

static struct attribute *part_attrs[] = {
	&dev_attr_start.attr,
	&dev_attr_size.attr,
	&dev_attr_stat.attr,
#ifdef CONFIG_FAIL_MAKE_REQUEST
	&dev_attr_fail.attr,
#endif
	NULL
};

static struct attribute_group part_attr_group = {
	.attrs = part_attrs,
};

static struct attribute_group *part_attr_groups[] = {
	&part_attr_group,
	NULL
};

static void part_release(struct device *dev)
{
	struct hd_struct *p = dev_to_part(dev);
	kfree(p);
}

struct device_type part_type = {
	.name		= "partition",
	.groups		= part_attr_groups,
	.release	= part_release,
};

static inline void partition_sysfs_add_subdir(struct hd_struct *p)
{
	struct kobject *k;

	k = kobject_get(&p->dev.kobj);
	p->holder_dir = kobject_create_and_add("holders", k);
	kobject_put(k);
}

static inline void disk_sysfs_add_subdirs(struct gendisk *disk)
{
	struct kobject *k;

	k = kobject_get(&disk->dev.kobj);
	disk->holder_dir = kobject_create_and_add("holders", k);
	disk->slave_dir = kobject_create_and_add("slaves", k);
	kobject_put(k);
}

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->ios[0] = p->ios[1] = 0;
	p->sectors[0] = p->sectors[1] = 0;
	kobject_unregister(p->holder_dir);
	device_del(&p->dev);
	put_device(&p->dev);
}

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

	p = kzalloc(sizeof(*p), GFP_KERNEL);
	if (!p)
		return;

	p->start_sect = start;
	p->nr_sects = len;
	p->partno = part;
	p->policy = disk->policy;

	if (isdigit(disk->dev.bus_id[strlen(disk->dev.bus_id)-1]))
		snprintf(p->dev.bus_id, BUS_ID_SIZE,
		"%sp%d", disk->dev.bus_id, part);
	else
		snprintf(p->dev.bus_id, BUS_ID_SIZE,
			 "%s%d", disk->dev.bus_id, part);

	device_initialize(&p->dev);
	p->dev.devt = MKDEV(disk->major, disk->first_minor + part);
	p->dev.class = &block_class;
	p->dev.type = &part_type;
	p->dev.parent = &disk->dev;
	disk->part[part-1] = p;

	/* delay uevent until 'holders' subdir is created */
	p->dev.uevent_suppress = 1;
	device_add(&p->dev);
	partition_sysfs_add_subdir(p);
	p->dev.uevent_suppress = 0;
	if (flags & ADDPART_FLAG_WHOLEDISK) {
		static struct attribute addpartattr = {
			.name = "whole_disk",
			.mode = S_IRUSR | S_IRGRP | S_IROTH,
		};
		err = sysfs_create_file(&p->dev.kobj, &addpartattr);
	}

	/* suppress uevent if the disk supresses it */
	if (!disk->dev.uevent_suppress)
		kobject_uevent(&p->dev.kobj, KOBJ_ADD);
}

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

	disk->dev.parent = disk->driverfs_dev;
	disk->dev.devt = MKDEV(disk->major, disk->first_minor);

	strlcpy(disk->dev.bus_id, disk->disk_name, KOBJ_NAME_LEN);
	/* ewww... some of these buggers have / in the name... */
	s = strchr(disk->dev.bus_id, '/');
	if (s)
		*s = '!';

	/* delay uevents, until we scanned partition table */
	disk->dev.uevent_suppress = 1;

	if (device_add(&disk->dev))
		return;
#ifndef CONFIG_SYSFS_DEPRECATED
	err = sysfs_create_link(block_depr, &disk->dev.kobj,
				kobject_name(&disk->dev.kobj));
	if (err) {
		device_del(&disk->dev);
		return;
	}
#endif
	disk_sysfs_add_subdirs(disk);

	/* No minors to use for partitions */
	if (disk->minors == 1)
		goto exit;

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

	bdev = bdget_disk(disk, 0);
	if (!bdev)
		goto exit;

	bdev->bd_invalidated = 1;
	err = blkdev_get(bdev, FMODE_READ, 0);
	if (err < 0)
		goto exit;
	blkdev_put(bdev);

exit:
	/* announce disk after possible partitions are created */
	disk->dev.uevent_suppress = 0;
	kobject_uevent(&disk->dev.kobj, KOBJ_ADD);

	/* announce possible partitions */
	for (i = 1; i < disk->minors; i++) {
		p = disk->part[i-1];
		if (!p || !p->nr_sects)
			continue;
		kobject_uevent(&p->dev.kobj, KOBJ_ADD);
	}
}

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;
	if (IS_ERR(state))	/* I/O error reading the partition table */
		return -EIO;
	for (p = 1; p < state->limit; p++) {
		sector_t size = state->parts[p].size;
		sector_t from = state->parts[p].from;
		if (!size)
			continue;
		if (from + size > get_capacity(disk)) {
			printk(" %s: p%d exceeds device capacity\n",
				disk->disk_name, p);
		}
		add_partition(disk, p, from, size, state->parts[p].flags);
#ifdef CONFIG_BLK_DEV_MD
		if (state->parts[p].flags & ADDPART_FLAG_RAID)
			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_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
				 NULL);
	if (!IS_ERR(page)) {
		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 = 0;

	kobject_unregister(disk->holder_dir);
	kobject_unregister(disk->slave_dir);
	disk->driverfs_dev = NULL;
#ifndef CONFIG_SYSFS_DEPRECATED
	sysfs_remove_link(block_depr, disk->dev.bus_id);
#endif
	device_del(&disk->dev);
}
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>
1da177e4 LT	21
1da177e4 LT	22	#include "check.h"
1da177e4 LT	23
	24	#include "acorn.h"
	25	#include "amiga.h"
	26	#include "atari.h"
	27	#include "ldm.h"
	28	#include "mac.h"
	29	#include "msdos.h"
	30	#include "osf.h"
	31	#include "sgi.h"
	32	#include "sun.h"
	33	#include "ibm.h"
	34	#include "ultrix.h"
	35	#include "efi.h"
0e6e1db4	36	#include "karma.h"
19d0e8ce	37	#include "sysv68.h"
1da177e4 LT	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,
0e6e1db4 BC	105	#endif
	106	#ifdef CONFIG_KARMA_PARTITION
	107	karma_partition,
19d0e8ce PDM	108	#endif
	109	#ifdef CONFIG_SYSV68_PARTITION
	110	sysv68_partition,
1da177e4 LT	111	#endif
	112	NULL
	113	};
	114
	115	/*
	116	* disk_name() is used by partition check code and the genhd driver.
	117	* It formats the devicename of the indicated disk into
	118	* the supplied buffer (of size at least 32), and returns
	119	* a pointer to that same buffer (for convenience).
	120	*/
	121
	122	char disk_name(struct gendisk hd, int part, char *buf)
	123	{
	124	if (!part)
	125	snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
	126	else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
	127	snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, part);
	128	else
	129	snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, part);
	130
	131	return buf;
	132	}
	133
	134	const char bdevname(struct block_device bdev, char *buf)
	135	{
	136	int part = MINOR(bdev->bd_dev) - bdev->bd_disk->first_minor;
	137	return disk_name(bdev->bd_disk, part, buf);
	138	}
	139
	140	EXPORT_SYMBOL(bdevname);
	141
	142	/*
	143	* There's very little reason to use this, you should really
	144	* have a struct block_device just about everywhere and use
	145	* bdevname() instead.
	146	*/
	147	const char __bdevname(dev_t dev, char buffer)
	148	{
	149	scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
	150	MAJOR(dev), MINOR(dev));
	151	return buffer;
	152	}
	153
	154	EXPORT_SYMBOL(__bdevname);
	155
	156	static struct parsed_partitions *
	157	check_partition(struct gendisk hd, struct block_device bdev)
	158	{
	159	struct parsed_partitions *state;
57881dd9	160	int i, res, err;
1da177e4 LT	161
	162	state = kmalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
	163	if (!state)
	164	return NULL;
	165
a2964188 GKH	166	disk_name(hd, 0, state->name);
	167	printk(KERN_INFO " %s:", state->name);
	168	if (isdigit(state->name[strlen(state->name)-1]))
1da177e4	169	sprintf(state->name, "p");
a2964188	170
1da177e4	171	state->limit = hd->minors;
57881dd9	172	i = res = err = 0;
1da177e4 LT	173	while (!res && check_part[i]) {
	174	memset(&state->parts, 0, sizeof(state->parts));
	175	res = check_part[i++](state, bdev);
57881dd9 S	176	if (res < 0) {
	177	/* We have hit an I/O error which we don't report now.
	178	* But record it, and let the others do their job.
	179	*/
	180	err = res;
	181	res = 0;
	182	}
	183
1da177e4 LT	184	}
	185	if (res > 0)
	186	return state;
9bebff6c	187	if (err)
57881dd9 S	188	/* The partition is unrecognized. So report I/O errors if there were any */
57881dd9 S	189	res = err;
1da177e4 LT	190	if (!res)
	191	printk(" unknown partition table\n");
	192	else if (warn_no_part)
	193	printk(" unable to read partition table\n");
	194	kfree(state);
5127d002	195	return ERR_PTR(res);
1da177e4 LT	196	}
1da177e4 LT	197
edfaa7c3 KS	198	static ssize_t part_start_show(struct device *dev,
edfaa7c3 KS	199	struct device_attribute attr, char buf)
1da177e4	200	{
edfaa7c3	201	struct hd_struct *p = dev_to_part(dev);
a7fd6706	202
edfaa7c3	203	return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
1da177e4 LT	204	}
1da177e4 LT	205
edfaa7c3 KS	206	static ssize_t part_size_show(struct device *dev,
edfaa7c3 KS	207	struct device_attribute attr, char buf)
a7fd6706	208	{
edfaa7c3 KS	209	struct hd_struct *p = dev_to_part(dev);
edfaa7c3 KS	210	return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
a7fd6706	211	}
edfaa7c3 KS	212
	213	static ssize_t part_stat_show(struct device *dev,
	214	struct device_attribute attr, char buf)
1da177e4	215	{
edfaa7c3 KS	216	struct hd_struct *p = dev_to_part(dev);
	217
	218	return sprintf(buf, "%8u %8llu %8u %8llu\n",
a362357b JA	219	p->ios[0], (unsigned long long)p->sectors[0],
a362357b JA	220	p->ios[1], (unsigned long long)p->sectors[1]);
1da177e4	221	}
1da177e4	222
c17bb495	223	#ifdef CONFIG_FAIL_MAKE_REQUEST
edfaa7c3 KS	224	static ssize_t part_fail_show(struct device *dev,
	225	struct device_attribute attr, char buf)
	226	{
	227	struct hd_struct *p = dev_to_part(dev);
c17bb495	228
edfaa7c3 KS	229	return sprintf(buf, "%d\n", p->make_it_fail);
	230	}
	231
	232	static ssize_t part_fail_store(struct device *dev,
	233	struct device_attribute *attr,
c17bb495 AM	234	const char *buf, size_t count)
c17bb495 AM	235	{
edfaa7c3	236	struct hd_struct *p = dev_to_part(dev);
c17bb495 AM	237	int i;
	238
	239	if (count > 0 && sscanf(buf, "%d", &i) > 0)
	240	p->make_it_fail = (i == 0) ? 0 : 1;
	241
	242	return count;
	243	}
edfaa7c3	244	#endif
c17bb495	245
edfaa7c3 KS	246	static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
	247	static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
	248	static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
	249	#ifdef CONFIG_FAIL_MAKE_REQUEST
	250	static struct device_attribute dev_attr_fail =
	251	__ATTR(make-it-fail, S_IRUGO\|S_IWUSR, part_fail_show, part_fail_store);
c17bb495 AM	252	#endif
c17bb495 AM	253
edfaa7c3 KS	254	static struct attribute *part_attrs[] = {
	255	&dev_attr_start.attr,
	256	&dev_attr_size.attr,
	257	&dev_attr_stat.attr,
c17bb495	258	#ifdef CONFIG_FAIL_MAKE_REQUEST
edfaa7c3	259	&dev_attr_fail.attr,
c17bb495	260	#endif
edfaa7c3	261	NULL
1da177e4 LT	262	};
1da177e4 LT	263
edfaa7c3 KS	264	static struct attribute_group part_attr_group = {
	265	.attrs = part_attrs,
	266	};
1da177e4	267
edfaa7c3 KS	268	static struct attribute_group *part_attr_groups[] = {
	269	&part_attr_group,
	270	NULL
	271	};
	272
	273	static void part_release(struct device *dev)
1da177e4	274	{
edfaa7c3	275	struct hd_struct *p = dev_to_part(dev);
1da177e4 LT	276	kfree(p);
	277	}
	278
edfaa7c3 KS	279	struct device_type part_type = {
	280	.name = "partition",
	281	.groups = part_attr_groups,
1da177e4	282	.release = part_release,
1da177e4 LT	283	};
1da177e4 LT	284
6a4d44c1 JN	285	static inline void partition_sysfs_add_subdir(struct hd_struct *p)
	286	{
	287	struct kobject *k;
	288
edfaa7c3	289	k = kobject_get(&p->dev.kobj);
4ff6abff	290	p->holder_dir = kobject_create_and_add("holders", k);
6a4d44c1 JN	291	kobject_put(k);
	292	}
	293
	294	static inline void disk_sysfs_add_subdirs(struct gendisk *disk)
	295	{
	296	struct kobject *k;
	297
edfaa7c3	298	k = kobject_get(&disk->dev.kobj);
4ff6abff GKH	299	disk->holder_dir = kobject_create_and_add("holders", k);
4ff6abff GKH	300	disk->slave_dir = kobject_create_and_add("slaves", k);
6a4d44c1 JN	301	kobject_put(k);
6a4d44c1 JN	302	}
6a4d44c1	303
1da177e4 LT	304	void delete_partition(struct gendisk *disk, int part)
	305	{
	306	struct hd_struct *p = disk->part[part-1];
edfaa7c3	307
1da177e4 LT	308	if (!p)
	309	return;
	310	if (!p->nr_sects)
	311	return;
	312	disk->part[part-1] = NULL;
	313	p->start_sect = 0;
	314	p->nr_sects = 0;
a362357b JA	315	p->ios[0] = p->ios[1] = 0;
a362357b JA	316	p->sectors[0] = p->sectors[1] = 0;
b92be9f1	317	kobject_unregister(p->holder_dir);
edfaa7c3 KS	318	device_del(&p->dev);
edfaa7c3 KS	319	put_device(&p->dev);
1da177e4 LT	320	}
1da177e4 LT	321
d18d7682	322	void add_partition(struct gendisk *disk, int part, sector_t start, sector_t len, int flags)
1da177e4 LT	323	{
1da177e4 LT	324	struct hd_struct *p;
edfaa7c3	325	int err;
1da177e4	326
dd00cc48	327	p = kzalloc(sizeof(*p), GFP_KERNEL);
1da177e4 LT	328	if (!p)
1da177e4 LT	329	return;
edfaa7c3	330
1da177e4 LT	331	p->start_sect = start;
	332	p->nr_sects = len;
	333	p->partno = part;
25e206b5	334	p->policy = disk->policy;
1da177e4	335
edfaa7c3 KS	336	if (isdigit(disk->dev.bus_id[strlen(disk->dev.bus_id)-1]))
	337	snprintf(p->dev.bus_id, BUS_ID_SIZE,
	338	"%sp%d", disk->dev.bus_id, part);
1da177e4	339	else
edfaa7c3 KS	340	snprintf(p->dev.bus_id, BUS_ID_SIZE,
	341	"%s%d", disk->dev.bus_id, part);
	342
	343	device_initialize(&p->dev);
	344	p->dev.devt = MKDEV(disk->major, disk->first_minor + part);
	345	p->dev.class = &block_class;
	346	p->dev.type = &part_type;
	347	p->dev.parent = &disk->dev;
	348	disk->part[part-1] = p;
	349
	350	/* delay uevent until 'holders' subdir is created */
	351	p->dev.uevent_suppress = 1;
	352	device_add(&p->dev);
	353	partition_sysfs_add_subdir(p);
	354	p->dev.uevent_suppress = 0;
d18d7682 FMDN	355	if (flags & ADDPART_FLAG_WHOLEDISK) {
	356	static struct attribute addpartattr = {
	357	.name = "whole_disk",
	358	.mode = S_IRUSR \| S_IRGRP \| S_IROTH,
d18d7682	359	};
edfaa7c3	360	err = sysfs_create_file(&p->dev.kobj, &addpartattr);
d18d7682	361	}
1da177e4	362
edfaa7c3 KS	363	/* suppress uevent if the disk supresses it */
	364	if (!disk->dev.uevent_suppress)
	365	kobject_uevent(&p->dev.kobj, KOBJ_ADD);
1da177e4 LT	366	}
	367
	368	/* Not exported, helper to add_disk(). */
	369	void register_disk(struct gendisk *disk)
	370	{
	371	struct block_device *bdev;
	372	char *s;
d4d7e5df KS	373	int i;
d4d7e5df KS	374	struct hd_struct *p;
1da177e4 LT	375	int err;
1da177e4 LT	376
edfaa7c3 KS	377	disk->dev.parent = disk->driverfs_dev;
	378	disk->dev.devt = MKDEV(disk->major, disk->first_minor);
	379
	380	strlcpy(disk->dev.bus_id, disk->disk_name, KOBJ_NAME_LEN);
	381	/* ewww... some of these buggers have / in the name... */
	382	s = strchr(disk->dev.bus_id, '/');
1da177e4 LT	383	if (s)
1da177e4 LT	384	*s = '!';
edfaa7c3 KS	385
	386	/* delay uevents, until we scanned partition table */
	387	disk->dev.uevent_suppress = 1;
	388
	389	if (device_add(&disk->dev))
1da177e4	390	return;
edfaa7c3 KS	391	#ifndef CONFIG_SYSFS_DEPRECATED
	392	err = sysfs_create_link(block_depr, &disk->dev.kobj,
	393	kobject_name(&disk->dev.kobj));
eee44cca	394	if (err) {
edfaa7c3	395	device_del(&disk->dev);
eee44cca JG	396	return;
eee44cca JG	397	}
edfaa7c3 KS	398	#endif
edfaa7c3 KS	399	disk_sysfs_add_subdirs(disk);
1da177e4 LT	400
1da177e4 LT	401	/* No minors to use for partitions */
a2964188	402	if (disk->minors == 1)
d4d7e5df	403	goto exit;
1da177e4 LT	404
	405	/* No such device (e.g., media were just removed) */
	406	if (!get_capacity(disk))
d4d7e5df	407	goto exit;
1da177e4 LT	408
	409	bdev = bdget_disk(disk, 0);
	410	if (!bdev)
d4d7e5df	411	goto exit;
1da177e4 LT	412
1da177e4 LT	413	bdev->bd_invalidated = 1;
d4d7e5df	414	err = blkdev_get(bdev, FMODE_READ, 0);
d4d7e5df KS	415	if (err < 0)
d4d7e5df KS	416	goto exit;
1da177e4	417	blkdev_put(bdev);
d4d7e5df KS	418
d4d7e5df KS	419	exit:
edfaa7c3 KS	420	/* announce disk after possible partitions are created */
	421	disk->dev.uevent_suppress = 0;
	422	kobject_uevent(&disk->dev.kobj, KOBJ_ADD);
d4d7e5df KS	423
	424	/* announce possible partitions */
	425	for (i = 1; i < disk->minors; i++) {
	426	p = disk->part[i-1];
	427	if (!p \|\| !p->nr_sects)
	428	continue;
edfaa7c3	429	kobject_uevent(&p->dev.kobj, KOBJ_ADD);
d4d7e5df	430	}
1da177e4 LT	431	}
	432
	433	int rescan_partitions(struct gendisk disk, struct block_device bdev)
	434	{
	435	struct parsed_partitions *state;
	436	int p, res;
	437
	438	if (bdev->bd_part_count)
	439	return -EBUSY;
	440	res = invalidate_partition(disk, 0);
	441	if (res)
	442	return res;
	443	bdev->bd_invalidated = 0;
	444	for (p = 1; p < disk->minors; p++)
	445	delete_partition(disk, p);
	446	if (disk->fops->revalidate_disk)
	447	disk->fops->revalidate_disk(disk);
	448	if (!get_capacity(disk) \|\| !(state = check_partition(disk, bdev)))
	449	return 0;
5127d002	450	if (IS_ERR(state)) /* I/O error reading the partition table */
b74a2f09	451	return -EIO;
1da177e4 LT	452	for (p = 1; p < state->limit; p++) {
	453	sector_t size = state->parts[p].size;
	454	sector_t from = state->parts[p].from;
	455	if (!size)
	456	continue;
98bd34ea MM	457	if (from + size > get_capacity(disk)) {
	458	printk(" %s: p%d exceeds device capacity\n",
	459	disk->disk_name, p);
	460	}
d18d7682	461	add_partition(disk, p, from, size, state->parts[p].flags);
1da177e4	462	#ifdef CONFIG_BLK_DEV_MD
d18d7682	463	if (state->parts[p].flags & ADDPART_FLAG_RAID)
1da177e4 LT	464	md_autodetect_dev(bdev->bd_dev+p);
	465	#endif
	466	}
	467	kfree(state);
	468	return 0;
	469	}
	470
	471	unsigned char read_dev_sector(struct block_device bdev, sector_t n, Sector *p)
	472	{
	473	struct address_space *mapping = bdev->bd_inode->i_mapping;
	474	struct page *page;
	475
090d2b18 PE	476	page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
090d2b18 PE	477	NULL);
1da177e4	478	if (!IS_ERR(page)) {
1da177e4 LT	479	if (PageError(page))
	480	goto fail;
	481	p->v = page;
	482	return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
	483	fail:
	484	page_cache_release(page);
	485	}
	486	p->v = NULL;
	487	return NULL;
	488	}
	489
	490	EXPORT_SYMBOL(read_dev_sector);
	491
	492	void del_gendisk(struct gendisk *disk)
	493	{
	494	int p;
	495
	496	/* invalidate stuff */
	497	for (p = disk->minors - 1; p > 0; p--) {
	498	invalidate_partition(disk, p);
	499	delete_partition(disk, p);
	500	}
	501	invalidate_partition(disk, 0);
	502	disk->capacity = 0;
	503	disk->flags &= ~GENHD_FL_UP;
	504	unlink_gendisk(disk);
	505	disk_stat_set_all(disk, 0);
20e5c81f	506	disk->stamp = 0;
1da177e4	507
b92be9f1 MK	508	kobject_unregister(disk->holder_dir);
b92be9f1 MK	509	kobject_unregister(disk->slave_dir);
edfaa7c3 KS	510	disk->driverfs_dev = NULL;
	511	#ifndef CONFIG_SYSFS_DEPRECATED
	512	sysfs_remove_link(block_depr, disk->dev.bus_id);
	513	#endif
	514	device_del(&disk->dev);
1da177e4	515	}