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/*
* 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/config.h>
#include <linux/fs.h>
#include <linux/genhd.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/blk.h>
#include <linux/init.h>
#include <linux/raid/md.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"
extern int *blk_size[];
int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
static int (*check_part[])(struct gendisk *hd, struct block_device *bdev, unsigned long first_sect, int first_minor) = {
#ifdef CONFIG_ACORN_PARTITION
acorn_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_SGI_PARTITION
sgi_partition,
#endif
#ifdef CONFIG_ULTRIX_PARTITION
ultrix_partition,
#endif
#ifdef CONFIG_IBM_PARTITION
ibm_partition,
#endif
NULL
};
/*
* This is ucking fugly but its probably the best thing for 2.4.x
* Take it as a clear reminder than we should put the device name
* generation in the object kdev_t points to in 2.5.
*/
#ifdef CONFIG_ARCH_S390
int (*genhd_dasd_name)(char*,int,int,struct gendisk*) = NULL;
EXPORT_SYMBOL(genhd_dasd_name);
#endif
/*
* disk_name() is used by partition check code and the md 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 minor, char *buf)
{
const char *maj = hd->major_name;
unsigned int unit = (minor >> hd->minor_shift);
unsigned int part = (minor & ((1 << hd->minor_shift) -1 ));
if ((unit < hd->nr_real) && hd->part[minor].de) {
int pos;
pos = devfs_generate_path (hd->part[minor].de, buf, 64);
if (pos >= 0)
return buf + pos;
}
#ifdef CONFIG_ARCH_S390
if (genhd_dasd_name
&& genhd_dasd_name (buf, unit, part, hd) == 0)
return buf;
#endif
/*
* IDE devices use multiple major numbers, but the drives
* are named as: {hda,hdb}, {hdc,hdd}, {hde,hdf}, {hdg,hdh}..
* This requires special handling here.
*/
switch (hd->major) {
case IDE9_MAJOR:
unit += 2;
case IDE8_MAJOR:
unit += 2;
case IDE7_MAJOR:
unit += 2;
case IDE6_MAJOR:
unit += 2;
case IDE5_MAJOR:
unit += 2;
case IDE4_MAJOR:
unit += 2;
case IDE3_MAJOR:
unit += 2;
case IDE2_MAJOR:
unit += 2;
case IDE1_MAJOR:
unit += 2;
case IDE0_MAJOR:
maj = "hd";
break;
case MD_MAJOR:
sprintf(buf, "%s%d", maj, unit);
return buf;
}
if (hd->major >= SCSI_DISK1_MAJOR && hd->major <= SCSI_DISK7_MAJOR) {
unit = unit + (hd->major - SCSI_DISK1_MAJOR + 1) * 16;
if (unit+'a' > 'z') {
unit -= 26;
sprintf(buf, "sd%c%c", 'a' + unit / 26, 'a' + unit % 26);
if (part)
sprintf(buf + 4, "%d", part);
return buf;
}
}
if (hd->major >= COMPAQ_SMART2_MAJOR && hd->major <= COMPAQ_SMART2_MAJOR+7) {
int ctlr = hd->major - COMPAQ_SMART2_MAJOR;
if (part == 0)
sprintf(buf, "%s/c%dd%d", maj, ctlr, unit);
else
sprintf(buf, "%s/c%dd%dp%d", maj, ctlr, unit, part);
return buf;
}
if (hd->major >= COMPAQ_CISS_MAJOR && hd->major <= COMPAQ_CISS_MAJOR+7) {
int ctlr = hd->major - COMPAQ_CISS_MAJOR;
if (part == 0)
sprintf(buf, "%s/c%dd%d", maj, ctlr, unit);
else
sprintf(buf, "%s/c%dd%dp%d", maj, ctlr, unit, part);
return buf;
}
if (hd->major >= DAC960_MAJOR && hd->major <= DAC960_MAJOR+7) {
int ctlr = hd->major - DAC960_MAJOR;
if (part == 0)
sprintf(buf, "%s/c%dd%d", maj, ctlr, unit);
else
sprintf(buf, "%s/c%dd%dp%d", maj, ctlr, unit, part);
return buf;
}
if (hd->major == ATARAID_MAJOR) {
int disk = minor >> hd->minor_shift;
int part = minor & (( 1 << hd->minor_shift) - 1);
if (part == 0)
sprintf(buf, "%s/d%d", maj, disk);
else
sprintf(buf, "%s/d%dp%d", maj, disk, part);
return buf;
}
if (part)
sprintf(buf, "%s%c%d", maj, unit+'a', part);
else
sprintf(buf, "%s%c", maj, unit+'a');
return buf;
}
/*
* Add a partitions details to the devices partition description.
*/
void add_gd_partition(struct gendisk *hd, int minor, int start, int size)
{
#ifndef CONFIG_DEVFS_FS
char buf[40];
#endif
hd->part[minor].start_sect = start;
hd->part[minor].nr_sects = size;
#ifdef CONFIG_DEVFS_FS
printk(" p%d", (minor & ((1 << hd->minor_shift) - 1)));
#else
if ((hd->major >= COMPAQ_SMART2_MAJOR+0 && hd->major <= COMPAQ_SMART2_MAJOR+7) ||
(hd->major >= COMPAQ_CISS_MAJOR+0 && hd->major <= COMPAQ_CISS_MAJOR+7))
printk(" p%d", (minor & ((1 << hd->minor_shift) - 1)));
else
printk(" %s", disk_name(hd, minor, buf));
#endif
}
static void check_partition(struct gendisk *hd, kdev_t dev, int first_part_minor)
{
devfs_handle_t de = NULL;
static int first_time = 1;
unsigned long first_sector;
struct block_device *bdev;
char buf[64];
int i;
if (first_time)
printk(KERN_INFO "Partition check:\n");
first_time = 0;
first_sector = hd->part[MINOR(dev)].start_sect;
/*
* This is a kludge to allow the partition check to be
* skipped for specific drives (e.g. IDE CD-ROM drives)
*/
if ((int)first_sector == -1) {
hd->part[MINOR(dev)].start_sect = 0;
return;
}
if (hd->de_arr)
de = hd->de_arr[MINOR(dev) >> hd->minor_shift];
i = devfs_generate_path (de, buf, sizeof buf);
if (i >= 0)
printk(KERN_INFO " /dev/%s:", buf + i);
else
printk(KERN_INFO " %s:", disk_name(hd, MINOR(dev), buf));
bdev = bdget(kdev_t_to_nr(dev));
bdev->bd_inode->i_size = (loff_t)hd->part[MINOR(dev)].nr_sects << 9;
bdev->bd_inode->i_blkbits = blksize_bits(block_size(dev));
for (i = 0; check_part[i]; i++) {
int res;
res = check_part[i](hd, bdev, first_sector, first_part_minor);
if (res) {
if (res < 0 && warn_no_part)
printk(" unable to read partition table\n");
goto setup_devfs;
}
}
printk(" unknown partition table\n");
setup_devfs:
invalidate_bdev(bdev, 1);
truncate_inode_pages(bdev->bd_inode->i_mapping, 0);
bdput(bdev);
i = first_part_minor - 1;
devfs_register_partitions (hd, i, hd->sizes ? 0 : 1);
}
#ifdef CONFIG_DEVFS_FS
static void devfs_register_partition (struct gendisk *dev, int minor, int part)
{
int devnum = minor >> dev->minor_shift;
devfs_handle_t dir;
unsigned int devfs_flags = DEVFS_FL_DEFAULT;
char devname[16];
if (dev->part[minor + part].de) return;
dir = devfs_get_parent (dev->part[minor].de);
if (!dir) return;
if ( dev->flags && (dev->flags[devnum] & GENHD_FL_REMOVABLE) )
devfs_flags |= DEVFS_FL_REMOVABLE;
sprintf (devname, "part%d", part);
dev->part[minor + part].de =
devfs_register (dir, devname, devfs_flags,
dev->major, minor + part,
S_IFBLK | S_IRUSR | S_IWUSR,
dev->fops, NULL);
}
static struct unique_numspace disc_numspace = UNIQUE_NUMBERSPACE_INITIALISER;
static void devfs_register_disc (struct gendisk *dev, int minor)
{
int pos = 0;
int devnum = minor >> dev->minor_shift;
devfs_handle_t dir, slave;
unsigned int devfs_flags = DEVFS_FL_DEFAULT;
char dirname[64], symlink[16];
static devfs_handle_t devfs_handle;
if (dev->part[minor].de) return;
if ( dev->flags && (dev->flags[devnum] & GENHD_FL_REMOVABLE) )
devfs_flags |= DEVFS_FL_REMOVABLE;
if (dev->de_arr) {
dir = dev->de_arr[devnum];
if (!dir) /* Aware driver wants to block disc management */
return;
pos = devfs_generate_path (dir, dirname + 3, sizeof dirname-3);
if (pos < 0) return;
strncpy (dirname + pos, "../", 3);
}
else {
/* Unaware driver: construct "real" directory */
sprintf (dirname, "../%s/disc%d", dev->major_name, devnum);
dir = devfs_mk_dir (NULL, dirname + 3, NULL);
}
if (!devfs_handle)
devfs_handle = devfs_mk_dir (NULL, "discs", NULL);
dev->part[minor].number = devfs_alloc_unique_number (&disc_numspace);
sprintf (symlink, "disc%d", dev->part[minor].number);
devfs_mk_symlink (devfs_handle, symlink, DEVFS_FL_DEFAULT,
dirname + pos, &slave, NULL);
dev->part[minor].de =
devfs_register (dir, "disc", devfs_flags, dev->major, minor,
S_IFBLK | S_IRUSR | S_IWUSR, dev->fops, NULL);
devfs_auto_unregister (dev->part[minor].de, slave);
if (!dev->de_arr)
devfs_auto_unregister (slave, dir);
}
#endif /* CONFIG_DEVFS_FS */
void devfs_register_partitions (struct gendisk *dev, int minor, int unregister)
{
#ifdef CONFIG_DEVFS_FS
int part;
if (!unregister)
devfs_register_disc (dev, minor);
for (part = 1; part < dev->max_p; part++) {
if ( unregister || (dev->part[minor].nr_sects < 1) ||
(dev->part[part + minor].nr_sects < 1) ) {
devfs_unregister (dev->part[part + minor].de);
dev->part[part + minor].de = NULL;
continue;
}
devfs_register_partition (dev, minor, part);
}
if (unregister) {
devfs_unregister (dev->part[minor].de);
dev->part[minor].de = NULL;
devfs_dealloc_unique_number (&disc_numspace,
dev->part[minor].number);
}
#endif /* CONFIG_DEVFS_FS */
}
/*
* This function will re-read the partition tables for a given device,
* and set things back up again. There are some important caveats,
* however. You must ensure that no one is using the device, and no one
* can start using the device while this function is being executed.
*
* Much of the cleanup from the old partition tables should have already been
* done
*/
void register_disk(struct gendisk *gdev, kdev_t dev, unsigned minors,
struct block_device_operations *ops, long size)
{
if (!gdev)
return;
grok_partitions(gdev, MINOR(dev)>>gdev->minor_shift, minors, size);
}
void grok_partitions(struct gendisk *dev, int drive, unsigned minors, long size)
{
int i;
int first_minor = drive << dev->minor_shift;
int end_minor = first_minor + dev->max_p;
if(!dev->sizes)
blk_size[dev->major] = NULL;
dev->part[first_minor].nr_sects = size;
/* No such device or no minors to use for partitions */
if ( !size && dev->flags && (dev->flags[drive] & GENHD_FL_REMOVABLE) )
devfs_register_partitions (dev, first_minor, 0);
if (!size || minors == 1)
return;
if (dev->sizes) {
dev->sizes[first_minor] = size >> (BLOCK_SIZE_BITS - 9);
for (i = first_minor + 1; i < end_minor; i++)
dev->sizes[i] = 0;
}
blk_size[dev->major] = dev->sizes;
check_partition(dev, MKDEV(dev->major, first_minor), 1 + first_minor);
/*
* We need to set the sizes array before we will be able to access
* any of the partitions on this device.
*/
if (dev->sizes != NULL) { /* optional safeguard in ll_rw_blk.c */
for (i = first_minor; i < end_minor; i++)
dev->sizes[i] = dev->part[i].nr_sects >> (BLOCK_SIZE_BITS - 9);
}
}
unsigned char *read_dev_sector(struct block_device *bdev, unsigned long n, Sector *p)
{
struct address_space *mapping = bdev->bd_inode->i_mapping;
int sect = PAGE_CACHE_SIZE / 512;
struct page *page;
page = read_cache_page(mapping, n/sect,
(filler_t *)mapping->a_ops->readpage, NULL);
if (!IS_ERR(page)) {
wait_on_page(page);
if (!Page_Uptodate(page))
goto fail;
if (PageError(page))
goto fail;
p->v = page;
return (unsigned char *)page_address(page) + 512 * (n % sect);
fail:
page_cache_release(page);
}
p->v = NULL;
return NULL;
}
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