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-rw-r--r--fs/partitions/check.c445
1 files changed, 445 insertions, 0 deletions
diff --git a/fs/partitions/check.c b/fs/partitions/check.c
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+++ 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);
+}