351 lines
10 KiB
C
351 lines
10 KiB
C
/*
|
|
* Copyright (c) International Business Machines Corp., 2006
|
|
* Copyright (c) Nokia Corporation, 2006
|
|
*
|
|
* This program 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 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program 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 this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*
|
|
* Author: Artem Bityutskiy (Битюцкий Артём)
|
|
*
|
|
* Jan 2007: Alexander Schmidt, hacked per-volume update.
|
|
*/
|
|
|
|
/*
|
|
* This file contains implementation of the volume update functionality.
|
|
*
|
|
* The update operation is based on the per-volume update marker which is
|
|
* stored in the volume table. The update marker is set before the update
|
|
* starts, and removed after the update has been finished. So if the update was
|
|
* interrupted by an unclean re-boot or due to some other reasons, the update
|
|
* marker stays on the flash media and UBI finds it when it attaches the MTD
|
|
* device next time. If the update marker is set for a volume, the volume is
|
|
* treated as damaged and most I/O operations are prohibited. Only a new update
|
|
* operation is allowed.
|
|
*
|
|
* Note, in general it is possible to implement the update operation as a
|
|
* transaction with a roll-back capability.
|
|
*/
|
|
|
|
#include <linux/err.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/div64.h>
|
|
#include "ubi.h"
|
|
|
|
/**
|
|
* set_update_marker - set update marker.
|
|
* @ubi: UBI device description object
|
|
* @vol_id: volume ID
|
|
*
|
|
* This function sets the update marker flag for volume @vol_id. Returns zero
|
|
* in case of success and a negative error code in case of failure.
|
|
*/
|
|
static int set_update_marker(struct ubi_device *ubi, int vol_id)
|
|
{
|
|
int err;
|
|
struct ubi_vtbl_record vtbl_rec;
|
|
struct ubi_volume *vol = ubi->volumes[vol_id];
|
|
|
|
dbg_msg("set update marker for volume %d", vol_id);
|
|
|
|
if (vol->upd_marker) {
|
|
ubi_assert(ubi->vtbl[vol_id].upd_marker);
|
|
dbg_msg("already set");
|
|
return 0;
|
|
}
|
|
|
|
memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
|
|
vtbl_rec.upd_marker = 1;
|
|
|
|
mutex_lock(&ubi->volumes_mutex);
|
|
err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
|
|
mutex_unlock(&ubi->volumes_mutex);
|
|
vol->upd_marker = 1;
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* clear_update_marker - clear update marker.
|
|
* @ubi: UBI device description object
|
|
* @vol_id: volume ID
|
|
* @bytes: new data size in bytes
|
|
*
|
|
* This function clears the update marker for volume @vol_id, sets new volume
|
|
* data size and clears the "corrupted" flag (static volumes only). Returns
|
|
* zero in case of success and a negative error code in case of failure.
|
|
*/
|
|
static int clear_update_marker(struct ubi_device *ubi, int vol_id, long long bytes)
|
|
{
|
|
int err;
|
|
uint64_t tmp;
|
|
struct ubi_vtbl_record vtbl_rec;
|
|
struct ubi_volume *vol = ubi->volumes[vol_id];
|
|
|
|
dbg_msg("clear update marker for volume %d", vol_id);
|
|
|
|
memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
|
|
ubi_assert(vol->upd_marker && vtbl_rec.upd_marker);
|
|
vtbl_rec.upd_marker = 0;
|
|
|
|
if (vol->vol_type == UBI_STATIC_VOLUME) {
|
|
vol->corrupted = 0;
|
|
vol->used_bytes = tmp = bytes;
|
|
vol->last_eb_bytes = do_div(tmp, vol->usable_leb_size);
|
|
vol->used_ebs = tmp;
|
|
if (vol->last_eb_bytes)
|
|
vol->used_ebs += 1;
|
|
else
|
|
vol->last_eb_bytes = vol->usable_leb_size;
|
|
}
|
|
|
|
mutex_lock(&ubi->volumes_mutex);
|
|
err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
|
|
mutex_unlock(&ubi->volumes_mutex);
|
|
vol->upd_marker = 0;
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* ubi_start_update - start volume update.
|
|
* @ubi: UBI device description object
|
|
* @vol_id: volume ID
|
|
* @bytes: update bytes
|
|
*
|
|
* This function starts volume update operation. If @bytes is zero, the volume
|
|
* is just wiped out. Returns zero in case of success and a negative error code
|
|
* in case of failure.
|
|
*/
|
|
int ubi_start_update(struct ubi_device *ubi, int vol_id, long long bytes)
|
|
{
|
|
int i, err;
|
|
uint64_t tmp;
|
|
struct ubi_volume *vol = ubi->volumes[vol_id];
|
|
|
|
dbg_msg("start update of volume %d, %llu bytes", vol_id, bytes);
|
|
vol->updating = 1;
|
|
|
|
err = set_update_marker(ubi, vol_id);
|
|
if (err)
|
|
return err;
|
|
|
|
/* Before updating - wipe out the volume */
|
|
for (i = 0; i < vol->reserved_pebs; i++) {
|
|
err = ubi_eba_unmap_leb(ubi, vol, i);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
if (bytes == 0) {
|
|
err = clear_update_marker(ubi, vol_id, 0);
|
|
if (err)
|
|
return err;
|
|
err = ubi_wl_flush(ubi);
|
|
if (!err)
|
|
vol->updating = 0;
|
|
}
|
|
|
|
vol->upd_buf = vmalloc(ubi->leb_size);
|
|
if (!vol->upd_buf)
|
|
return -ENOMEM;
|
|
|
|
tmp = bytes;
|
|
vol->upd_ebs = !!do_div(tmp, vol->usable_leb_size);
|
|
vol->upd_ebs += tmp;
|
|
vol->upd_bytes = bytes;
|
|
vol->upd_received = 0;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* write_leb - write update data.
|
|
* @ubi: UBI device description object
|
|
* @vol_id: volume ID
|
|
* @lnum: logical eraseblock number
|
|
* @buf: data to write
|
|
* @len: data size
|
|
* @used_ebs: how many logical eraseblocks will this volume contain (static
|
|
* volumes only)
|
|
*
|
|
* This function writes update data to corresponding logical eraseblock. In
|
|
* case of dynamic volume, this function checks if the data contains 0xFF bytes
|
|
* at the end. If yes, the 0xFF bytes are cut and not written. So if the whole
|
|
* buffer contains only 0xFF bytes, the LEB is left unmapped.
|
|
*
|
|
* The reason why we skip the trailing 0xFF bytes in case of dynamic volume is
|
|
* that we want to make sure that more data may be appended to the logical
|
|
* eraseblock in future. Indeed, writing 0xFF bytes may have side effects and
|
|
* this PEB won't be writable anymore. So if one writes the file-system image
|
|
* to the UBI volume where 0xFFs mean free space - UBI makes sure this free
|
|
* space is writable after the update.
|
|
*
|
|
* We do not do this for static volumes because they are read-only. But this
|
|
* also cannot be done because we have to store per-LEB CRC and the correct
|
|
* data length.
|
|
*
|
|
* This function returns zero in case of success and a negative error code in
|
|
* case of failure.
|
|
*/
|
|
static int write_leb(struct ubi_device *ubi, int vol_id, int lnum, void *buf,
|
|
int len, int used_ebs)
|
|
{
|
|
int err, l;
|
|
struct ubi_volume *vol = ubi->volumes[vol_id];
|
|
|
|
if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
|
|
l = ALIGN(len, ubi->min_io_size);
|
|
memset(buf + len, 0xFF, l - len);
|
|
|
|
l = ubi_calc_data_len(ubi, buf, l);
|
|
if (l == 0) {
|
|
dbg_msg("all %d bytes contain 0xFF - skip", len);
|
|
return 0;
|
|
}
|
|
if (len != l)
|
|
dbg_msg("skip last %d bytes (0xFF)", len - l);
|
|
|
|
err = ubi_eba_write_leb(ubi, vol, lnum, buf, 0, l, UBI_UNKNOWN);
|
|
} else {
|
|
/*
|
|
* When writing static volume, and this is the last logical
|
|
* eraseblock, the length (@len) does not have to be aligned to
|
|
* the minimal flash I/O unit. The 'ubi_eba_write_leb_st()'
|
|
* function accepts exact (unaligned) length and stores it in
|
|
* the VID header. And it takes care of proper alignment by
|
|
* padding the buffer. Here we just make sure the padding will
|
|
* contain zeros, not random trash.
|
|
*/
|
|
memset(buf + len, 0, vol->usable_leb_size - len);
|
|
err = ubi_eba_write_leb_st(ubi, vol, lnum, buf, len,
|
|
UBI_UNKNOWN, used_ebs);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* ubi_more_update_data - write more update data.
|
|
* @vol: volume description object
|
|
* @buf: write data (user-space memory buffer)
|
|
* @count: how much bytes to write
|
|
*
|
|
* This function writes more data to the volume which is being updated. It may
|
|
* be called arbitrary number of times until all of the update data arrive.
|
|
* This function returns %0 in case of success, number of bytes written during
|
|
* the last call if the whole volume update was successfully finished, and a
|
|
* negative error code in case of failure.
|
|
*/
|
|
int ubi_more_update_data(struct ubi_device *ubi, int vol_id,
|
|
const void __user *buf, int count)
|
|
{
|
|
uint64_t tmp;
|
|
struct ubi_volume *vol = ubi->volumes[vol_id];
|
|
int lnum, offs, err = 0, len, to_write = count;
|
|
|
|
dbg_msg("write %d of %lld bytes, %lld already passed",
|
|
count, vol->upd_bytes, vol->upd_received);
|
|
|
|
if (ubi->ro_mode)
|
|
return -EROFS;
|
|
|
|
tmp = vol->upd_received;
|
|
offs = do_div(tmp, vol->usable_leb_size);
|
|
lnum = tmp;
|
|
|
|
if (vol->upd_received + count > vol->upd_bytes)
|
|
to_write = count = vol->upd_bytes - vol->upd_received;
|
|
|
|
/*
|
|
* When updating volumes, we accumulate whole logical eraseblock of
|
|
* data and write it at once.
|
|
*/
|
|
if (offs != 0) {
|
|
/*
|
|
* This is a write to the middle of the logical eraseblock. We
|
|
* copy the data to our update buffer and wait for more data or
|
|
* flush it if the whole eraseblock is written or the update
|
|
* is finished.
|
|
*/
|
|
|
|
len = vol->usable_leb_size - offs;
|
|
if (len > count)
|
|
len = count;
|
|
|
|
err = copy_from_user(vol->upd_buf + offs, buf, len);
|
|
if (err)
|
|
return -EFAULT;
|
|
|
|
if (offs + len == vol->usable_leb_size ||
|
|
vol->upd_received + len == vol->upd_bytes) {
|
|
int flush_len = offs + len;
|
|
|
|
/*
|
|
* OK, we gathered either the whole eraseblock or this
|
|
* is the last chunk, it's time to flush the buffer.
|
|
*/
|
|
ubi_assert(flush_len <= vol->usable_leb_size);
|
|
err = write_leb(ubi, vol_id, lnum, vol->upd_buf,
|
|
flush_len, vol->upd_ebs);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
vol->upd_received += len;
|
|
count -= len;
|
|
buf += len;
|
|
lnum += 1;
|
|
}
|
|
|
|
/*
|
|
* If we've got more to write, let's continue. At this point we know we
|
|
* are starting from the beginning of an eraseblock.
|
|
*/
|
|
while (count) {
|
|
if (count > vol->usable_leb_size)
|
|
len = vol->usable_leb_size;
|
|
else
|
|
len = count;
|
|
|
|
err = copy_from_user(vol->upd_buf, buf, len);
|
|
if (err)
|
|
return -EFAULT;
|
|
|
|
if (len == vol->usable_leb_size ||
|
|
vol->upd_received + len == vol->upd_bytes) {
|
|
err = write_leb(ubi, vol_id, lnum, vol->upd_buf, len,
|
|
vol->upd_ebs);
|
|
if (err)
|
|
break;
|
|
}
|
|
|
|
vol->upd_received += len;
|
|
count -= len;
|
|
lnum += 1;
|
|
buf += len;
|
|
}
|
|
|
|
ubi_assert(vol->upd_received <= vol->upd_bytes);
|
|
if (vol->upd_received == vol->upd_bytes) {
|
|
/* The update is finished, clear the update marker */
|
|
err = clear_update_marker(ubi, vol_id, vol->upd_bytes);
|
|
if (err)
|
|
return err;
|
|
err = ubi_wl_flush(ubi);
|
|
if (err == 0) {
|
|
err = to_write;
|
|
vfree(vol->upd_buf);
|
|
}
|
|
}
|
|
|
|
return err;
|
|
}
|