grub/include/grub/disk.h
Eric Snowberg 3434ddec0e ieee1275: obdisk driver
Add a new disk driver called obdisk for IEEE1275 platforms.  Currently
the only platform using this disk driver is SPARC, however other IEEE1275
platforms could start using it if they so choose.  While the functionality
within the current IEEE1275 ofdisk driver may be suitable for PPC and x86, it
presented too many problems on SPARC hardware.

Within the old ofdisk, there is not a way to determine the true canonical
name for the disk.  Within Open Boot, the same disk can have multiple names
but all reference the same disk.  For example the same disk can be referenced
by its SAS WWN, using this form:

/pci@302/pci@2/pci@0/pci@17/LSI,sas@0/disk@w5000cca02f037d6d,0

It can also be referenced by its PHY identifier using this form:

/pci@302/pci@2/pci@0/pci@17/LSI,sas@0/disk@p0

It can also be referenced by its Target identifier using this form:

/pci@302/pci@2/pci@0/pci@17/LSI,sas@0/disk@0

Also, when the LUN=0, it is legal to omit the ,0 from the device name.  So with
the disk above, before taking into account the device aliases, there are 6 ways
to reference the same disk.

Then it is possible to have 0 .. n device aliases all representing the same disk.
Within this new driver the true canonical name is determined using the the
IEEE1275 encode-unit and decode-unit commands when address_cells == 4.  This
will determine the true single canonical name for the device so multiple ihandles
are not opened for the same device.  This is what frequently happens with the old
ofdisk driver.  With some devices when they are opened multiple times it causes
the entire system to hang.

Another problem solved with this driver is devices that do not have a device
alias can be booted and used within GRUB. Within the old ofdisk, this was not
possible, unless it was the original boot device.  All devices behind a SAS
or SCSI parent can be found.   Within the old ofdisk, finding these disks
relied on there being an alias defined.  The alias requirement is not
necessary with this new driver.  It can also find devices behind a parent
after they have been hot-plugged.  This is something that is not possible
with the old ofdisk driver.

The old ofdisk driver also incorrectly assumes that the device pointing to by a
device alias is in its true canonical form. This assumption is never made with
this new driver.

Another issue solved with this driver is that it properly caches the ihandle
for all open devices.  The old ofdisk tries to do this by caching the last
opened ihandle.  However this does not work properly because the layer above
does not use a consistent device name for the same disk when calling into the
driver.  This is because the upper layer uses the bootpath value returned within
/chosen, other times it uses the device alias, and other times it uses the
value within grub.cfg.  It does not have a way to figure out that these devices
are the same disk.  This is not a problem with this new driver.

Due to the way GRUB repeatedly opens and closes the same disk. Caching the
ihandle is important on SPARC.  Without caching, some SAS devices can take
15 - 20 minutes to get to the GRUB menu. This ihandle caching is not possible
without correctly having the canonical disk name.

When available, this driver also tries to use the deblocker #blocks and
a way of determining the disk size.

Finally and probably most importantly, this new driver is also capable of
seeing all partitions on a GPT disk.  With the old driver, the GPT
partition table can not be read and only the first partition on the disk
can be seen.

Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2019-03-12 20:04:07 +01:00

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7.3 KiB
C

/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2002,2003,2004,2005,2006,2007,2008,2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef GRUB_DISK_HEADER
#define GRUB_DISK_HEADER 1
#include <config.h>
#include <grub/symbol.h>
#include <grub/err.h>
#include <grub/types.h>
#include <grub/device.h>
/* For NULL. */
#include <grub/mm.h>
/* These are used to set a device id. When you add a new disk device,
you must define a new id for it here. */
enum grub_disk_dev_id
{
GRUB_DISK_DEVICE_BIOSDISK_ID,
GRUB_DISK_DEVICE_OFDISK_ID,
GRUB_DISK_DEVICE_LOOPBACK_ID,
GRUB_DISK_DEVICE_EFIDISK_ID,
GRUB_DISK_DEVICE_DISKFILTER_ID,
GRUB_DISK_DEVICE_HOST_ID,
GRUB_DISK_DEVICE_ATA_ID,
GRUB_DISK_DEVICE_MEMDISK_ID,
GRUB_DISK_DEVICE_NAND_ID,
GRUB_DISK_DEVICE_SCSI_ID,
GRUB_DISK_DEVICE_CRYPTODISK_ID,
GRUB_DISK_DEVICE_ARCDISK_ID,
GRUB_DISK_DEVICE_HOSTDISK_ID,
GRUB_DISK_DEVICE_PROCFS_ID,
GRUB_DISK_DEVICE_CBFSDISK_ID,
GRUB_DISK_DEVICE_UBOOTDISK_ID,
GRUB_DISK_DEVICE_XEN,
GRUB_DISK_DEVICE_OBDISK_ID,
};
struct grub_disk;
#ifdef GRUB_UTIL
struct grub_disk_memberlist;
#endif
typedef enum
{
GRUB_DISK_PULL_NONE,
GRUB_DISK_PULL_REMOVABLE,
GRUB_DISK_PULL_RESCAN,
GRUB_DISK_PULL_MAX
} grub_disk_pull_t;
typedef int (*grub_disk_dev_iterate_hook_t) (const char *name, void *data);
/* Disk device. */
struct grub_disk_dev
{
/* The device name. */
const char *name;
/* The device id used by the cache manager. */
enum grub_disk_dev_id id;
/* Call HOOK with each device name, until HOOK returns non-zero. */
int (*iterate) (grub_disk_dev_iterate_hook_t hook, void *hook_data,
grub_disk_pull_t pull);
/* Open the device named NAME, and set up DISK. */
grub_err_t (*open) (const char *name, struct grub_disk *disk);
/* Close the disk DISK. */
void (*close) (struct grub_disk *disk);
/* Read SIZE sectors from the sector SECTOR of the disk DISK into BUF. */
grub_err_t (*read) (struct grub_disk *disk, grub_disk_addr_t sector,
grub_size_t size, char *buf);
/* Write SIZE sectors from BUF into the sector SECTOR of the disk DISK. */
grub_err_t (*write) (struct grub_disk *disk, grub_disk_addr_t sector,
grub_size_t size, const char *buf);
#ifdef GRUB_UTIL
struct grub_disk_memberlist *(*memberlist) (struct grub_disk *disk);
const char * (*raidname) (struct grub_disk *disk);
#endif
/* The next disk device. */
struct grub_disk_dev *next;
};
typedef struct grub_disk_dev *grub_disk_dev_t;
extern grub_disk_dev_t EXPORT_VAR (grub_disk_dev_list);
struct grub_partition;
typedef void (*grub_disk_read_hook_t) (grub_disk_addr_t sector,
unsigned offset, unsigned length,
void *data);
/* Disk. */
struct grub_disk
{
/* The disk name. */
const char *name;
/* The underlying disk device. */
grub_disk_dev_t dev;
/* The total number of sectors. */
grub_uint64_t total_sectors;
/* Logarithm of sector size. */
unsigned int log_sector_size;
/* Maximum number of sectors read divided by GRUB_DISK_CACHE_SIZE. */
unsigned int max_agglomerate;
/* The id used by the disk cache manager. */
unsigned long id;
/* The partition information. This is machine-specific. */
struct grub_partition *partition;
/* Called when a sector was read. OFFSET is between 0 and
the sector size minus 1, and LENGTH is between 0 and the sector size. */
grub_disk_read_hook_t read_hook;
/* Caller-specific data passed to the read hook. */
void *read_hook_data;
/* Device-specific data. */
void *data;
};
typedef struct grub_disk *grub_disk_t;
#ifdef GRUB_UTIL
struct grub_disk_memberlist
{
grub_disk_t disk;
struct grub_disk_memberlist *next;
};
typedef struct grub_disk_memberlist *grub_disk_memberlist_t;
#endif
/* The sector size. */
#define GRUB_DISK_SECTOR_SIZE 0x200
#define GRUB_DISK_SECTOR_BITS 9
/* The maximum number of disk caches. */
#define GRUB_DISK_CACHE_NUM 1021
/* The size of a disk cache in 512B units. Must be at least as big as the
largest supported sector size, currently 16K. */
#define GRUB_DISK_CACHE_BITS 6
#define GRUB_DISK_CACHE_SIZE (1 << GRUB_DISK_CACHE_BITS)
#define GRUB_DISK_MAX_MAX_AGGLOMERATE ((1 << (30 - GRUB_DISK_CACHE_BITS - GRUB_DISK_SECTOR_BITS)) - 1)
/* Return value of grub_disk_get_size() in case disk size is unknown. */
#define GRUB_DISK_SIZE_UNKNOWN 0xffffffffffffffffULL
/* This is called from the memory manager. */
void grub_disk_cache_invalidate_all (void);
void EXPORT_FUNC(grub_disk_dev_register) (grub_disk_dev_t dev);
void EXPORT_FUNC(grub_disk_dev_unregister) (grub_disk_dev_t dev);
static inline int
grub_disk_dev_iterate (grub_disk_dev_iterate_hook_t hook, void *hook_data)
{
grub_disk_dev_t p;
grub_disk_pull_t pull;
for (pull = 0; pull < GRUB_DISK_PULL_MAX; pull++)
for (p = grub_disk_dev_list; p; p = p->next)
if (p->iterate && (p->iterate) (hook, hook_data, pull))
return 1;
return 0;
}
grub_disk_t EXPORT_FUNC(grub_disk_open) (const char *name);
void EXPORT_FUNC(grub_disk_close) (grub_disk_t disk);
grub_err_t EXPORT_FUNC(grub_disk_read) (grub_disk_t disk,
grub_disk_addr_t sector,
grub_off_t offset,
grub_size_t size,
void *buf);
grub_err_t grub_disk_write (grub_disk_t disk,
grub_disk_addr_t sector,
grub_off_t offset,
grub_size_t size,
const void *buf);
extern grub_err_t (*EXPORT_VAR(grub_disk_write_weak)) (grub_disk_t disk,
grub_disk_addr_t sector,
grub_off_t offset,
grub_size_t size,
const void *buf);
grub_uint64_t EXPORT_FUNC(grub_disk_get_size) (grub_disk_t disk);
#if DISK_CACHE_STATS
void
EXPORT_FUNC(grub_disk_cache_get_performance) (unsigned long *hits, unsigned long *misses);
#endif
extern void (* EXPORT_VAR(grub_disk_firmware_fini)) (void);
extern int EXPORT_VAR(grub_disk_firmware_is_tainted);
static inline void
grub_stop_disk_firmware (void)
{
/* To prevent two drivers operating on the same disks. */
grub_disk_firmware_is_tainted = 1;
if (grub_disk_firmware_fini)
{
grub_disk_firmware_fini ();
grub_disk_firmware_fini = NULL;
}
}
/* Disk cache. */
struct grub_disk_cache
{
enum grub_disk_dev_id dev_id;
unsigned long disk_id;
grub_disk_addr_t sector;
char *data;
int lock;
};
extern struct grub_disk_cache EXPORT_VAR(grub_disk_cache_table)[GRUB_DISK_CACHE_NUM];
#if defined (GRUB_UTIL)
void grub_lvm_init (void);
void grub_ldm_init (void);
void grub_mdraid09_init (void);
void grub_mdraid1x_init (void);
void grub_diskfilter_init (void);
void grub_lvm_fini (void);
void grub_ldm_fini (void);
void grub_mdraid09_fini (void);
void grub_mdraid1x_fini (void);
void grub_diskfilter_fini (void);
#endif
#endif /* ! GRUB_DISK_HEADER */