1 files changed, 445 insertions, 0 deletions
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
new file mode 100644
index 000000000000..31cff785b3bd
--- /dev/null
+++ b/fs/partitions/check.c
@@ -0,0 +1,445 @@
+/*
+ *  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_NEC98_PARTITION
+	nec98_partition,	/* must be come before `msdos_partition' */
+#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);
+
+	/* 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_del(&disk->kobj);
+}