minix/sys/ufs/chfs/ebh.c

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/* $NetBSD: ebh.c,v 1.2 2011/11/25 11:15:24 ahoka Exp $ */
/*-
* Copyright (c) 2010 Department of Software Engineering,
* University of Szeged, Hungary
* Copyright (C) 2009 Ferenc Havasi <havasi@inf.u-szeged.hu>
* Copyright (C) 2009 Zoltan Sogor <weth@inf.u-szeged.hu>
* Copyright (C) 2009 David Tengeri <dtengeri@inf.u-szeged.hu>
* Copyright (C) 2009 Tamas Toth <ttoth@inf.u-szeged.hu>
* Copyright (C) 2010 Adam Hoka <ahoka@NetBSD.org>
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by the Department of Software Engineering, University of Szeged, Hungary
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "ebh.h"
/*****************************************************************************/
/* Flash specific operations */
/*****************************************************************************/
int nor_create_eb_hdr(struct chfs_eb_hdr *ebhdr, int lnr);
int nand_create_eb_hdr(struct chfs_eb_hdr *ebhdr, int lnr);
int nor_calc_data_offs(struct chfs_ebh *ebh, int pebnr, int offset);
int nand_calc_data_offs(struct chfs_ebh *ebh, int pebnr, int offset);
int nor_read_eb_hdr(struct chfs_ebh *ebh, int pebnr, struct chfs_eb_hdr *ebhdr);
int nand_read_eb_hdr(struct chfs_ebh *ebh, int pebnr, struct chfs_eb_hdr *ebhdr);
int nor_write_eb_hdr(struct chfs_ebh *ebh, int pebnr, struct chfs_eb_hdr *ebhdr);
int nand_write_eb_hdr(struct chfs_ebh *ebh, int pebnr,struct chfs_eb_hdr *ebhdr);
int nor_check_eb_hdr(struct chfs_ebh *ebh, void *buf);
int nand_check_eb_hdr(struct chfs_ebh *ebh, void *buf);
int nor_mark_eb_hdr_dirty_flash(struct chfs_ebh *ebh, int pebnr, int lid);
int nor_invalidate_eb_hdr(struct chfs_ebh *ebh, int pebnr);
int mark_eb_hdr_free(struct chfs_ebh *ebh, int pebnr, int ec);
int ltree_entry_cmp(struct chfs_ltree_entry *le1, struct chfs_ltree_entry *le2);
int peb_in_use_cmp(struct chfs_peb *peb1, struct chfs_peb *peb2);
int peb_free_cmp(struct chfs_peb *peb1, struct chfs_peb *peb2);
int add_peb_to_erase_queue(struct chfs_ebh *ebh, int pebnr, int ec,struct peb_queue *queue);
struct chfs_peb * find_peb_in_use(struct chfs_ebh *ebh, int pebnr);
int add_peb_to_free(struct chfs_ebh *ebh, int pebnr, int ec);
int add_peb_to_in_use(struct chfs_ebh *ebh, int pebnr, int ec);
void erase_callback(struct flash_erase_instruction *ei);
int free_peb(struct chfs_ebh *ebh);
int release_peb(struct chfs_ebh *ebh, int pebnr);
void erase_thread(void *data);
static void erase_thread_start(struct chfs_ebh *ebh);
static void erase_thread_stop(struct chfs_ebh *ebh);
int scan_leb_used_cmp(struct chfs_scan_leb *sleb1, struct chfs_scan_leb *sleb2);
int nor_scan_add_to_used(struct chfs_ebh *ebh, struct chfs_scan_info *si,struct chfs_eb_hdr *ebhdr, int pebnr, int leb_status);
int nor_process_eb(struct chfs_ebh *ebh, struct chfs_scan_info *si,
int pebnr, struct chfs_eb_hdr *ebhdr);
int nand_scan_add_to_used(struct chfs_ebh *ebh, struct chfs_scan_info *si,struct chfs_eb_hdr *ebhdr, int pebnr);
int nand_process_eb(struct chfs_ebh *ebh, struct chfs_scan_info *si,
int pebnr, struct chfs_eb_hdr *ebhdr);
struct chfs_scan_info *chfs_scan(struct chfs_ebh *ebh);
void scan_info_destroy(struct chfs_scan_info *si);
int scan_media(struct chfs_ebh *ebh);
int get_peb(struct chfs_ebh *ebh);
/**
* nor_create_eb_hdr - creates an eraseblock header for NOR flash
* @ebhdr: ebhdr to set
* @lnr: LEB number
*/
int
nor_create_eb_hdr(struct chfs_eb_hdr *ebhdr, int lnr)
{
ebhdr->u.nor_hdr.lid = htole32(lnr);
return 0;
}
/**
* nand_create_eb_hdr - creates an eraseblock header for NAND flash
* @ebhdr: ebhdr to set
* @lnr: LEB number
*/
int
nand_create_eb_hdr(struct chfs_eb_hdr *ebhdr, int lnr)
{
ebhdr->u.nand_hdr.lid = htole32(lnr);
return 0;
}
/**
* nor_calc_data_offs - calculates data offset on NOR flash
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number
* @offset: offset within the eraseblock
*/
int
nor_calc_data_offs(struct chfs_ebh *ebh, int pebnr, int offset)
{
return pebnr * ebh->flash_if->erasesize + offset +
CHFS_EB_EC_HDR_SIZE + CHFS_EB_HDR_NOR_SIZE;
}
/**
* nand_calc_data_offs - calculates data offset on NAND flash
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number
* @offset: offset within the eraseblock
*/
int
nand_calc_data_offs(struct chfs_ebh *ebh, int pebnr, int offset)
{
return pebnr * ebh->flash_if->erasesize + offset +
2 * ebh->flash_if->page_size;
}
/**
* nor_read_eb_hdr - read ereaseblock header from NOR flash
*
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number
* @ebhdr: whereto store the data
*
* Reads the eraseblock header from media.
* Returns zero in case of success, error code in case of fail.
*/
int
nor_read_eb_hdr(struct chfs_ebh *ebh,
int pebnr, struct chfs_eb_hdr *ebhdr)
{
int ret;
size_t retlen;
off_t ofs = pebnr * ebh->flash_if->erasesize;
KASSERT(pebnr >= 0 && pebnr < ebh->peb_nr);
ret = flash_read(ebh->flash_dev,
ofs, CHFS_EB_EC_HDR_SIZE,
&retlen, (unsigned char *) &ebhdr->ec_hdr);
if (ret || retlen != CHFS_EB_EC_HDR_SIZE)
return ret;
ofs += CHFS_EB_EC_HDR_SIZE;
ret = flash_read(ebh->flash_dev,
ofs, CHFS_EB_HDR_NOR_SIZE,
&retlen, (unsigned char *) &ebhdr->u.nor_hdr);
if (ret || retlen != CHFS_EB_HDR_NOR_SIZE)
return ret;
return 0;
}
/**
* nand_read_eb_hdr - read ereaseblock header from NAND flash
*
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number
* @ebhdr: whereto store the data
*
* Reads the eraseblock header from media. It is on the first two page.
* Returns zero in case of success, error code in case of fail.
*/
int
nand_read_eb_hdr(struct chfs_ebh *ebh, int pebnr,
struct chfs_eb_hdr *ebhdr)
{
int ret;
size_t retlen;
off_t ofs;
KASSERT(pebnr >= 0 && pebnr < ebh->peb_nr);
/* Read erase counter header from the first page. */
ofs = pebnr * ebh->flash_if->erasesize;
ret = flash_read(ebh->flash_dev,
ofs, CHFS_EB_EC_HDR_SIZE, &retlen,
(unsigned char *) &ebhdr->ec_hdr);
if (ret || retlen != CHFS_EB_EC_HDR_SIZE)
return ret;
/* Read NAND eraseblock header from the second page */
ofs += ebh->flash_if->page_size;
ret = flash_read(ebh->flash_dev,
ofs, CHFS_EB_HDR_NAND_SIZE, &retlen,
(unsigned char *) &ebhdr->u.nand_hdr);
if (ret || retlen != CHFS_EB_HDR_NAND_SIZE)
return ret;
return 0;
}
/**
* nor_write_eb_hdr - write ereaseblock header to NOR flash
*
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number whereto write
* @ebh: ebh to write
*
* Writes the eraseblock header to media.
* Returns zero in case of success, error code in case of fail.
*/
int
nor_write_eb_hdr(struct chfs_ebh *ebh, int pebnr, struct chfs_eb_hdr *ebhdr)
{
int ret, crc;
size_t retlen;
off_t ofs = pebnr * ebh->flash_if->erasesize + CHFS_EB_EC_HDR_SIZE;
ebhdr->u.nor_hdr.lid = ebhdr->u.nor_hdr.lid
| htole32(CHFS_LID_NOT_DIRTY_BIT);
crc = crc32(0, (uint8_t *)&ebhdr->u.nor_hdr + 4,
CHFS_EB_HDR_NOR_SIZE - 4);
ebhdr->u.nand_hdr.crc = htole32(crc);
KASSERT(pebnr >= 0 && pebnr < ebh->peb_nr);
ret = flash_write(ebh->flash_dev,
ofs, CHFS_EB_HDR_NOR_SIZE, &retlen,
(unsigned char *) &ebhdr->u.nor_hdr);
if (ret || retlen != CHFS_EB_HDR_NOR_SIZE)
return ret;
return 0;
}
/**
* nand_write_eb_hdr - write ereaseblock header to NAND flash
*
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number whereto write
* @ebh: ebh to write
*
* Writes the eraseblock header to media.
* Returns zero in case of success, error code in case of fail.
*/
int
nand_write_eb_hdr(struct chfs_ebh *ebh, int pebnr,
struct chfs_eb_hdr *ebhdr)
{
int ret, crc;
size_t retlen;
flash_off_t ofs;
KASSERT(pebnr >= 0 && pebnr < ebh->peb_nr);
ofs = pebnr * ebh->flash_if->erasesize +
ebh->flash_if->page_size;
ebhdr->u.nand_hdr.serial = htole64(++(*ebh->max_serial));
crc = crc32(0, (uint8_t *)&ebhdr->u.nand_hdr + 4,
CHFS_EB_HDR_NAND_SIZE - 4);
ebhdr->u.nand_hdr.crc = htole32(crc);
ret = flash_write(ebh->flash_dev, ofs,
CHFS_EB_HDR_NAND_SIZE, &retlen,
(unsigned char *) &ebhdr->u.nand_hdr);
if (ret || retlen != CHFS_EB_HDR_NAND_SIZE)
return ret;
return 0;
}
/**
* nor_check_eb_hdr - check ereaseblock header read from NOR flash
*
* @ebh: chfs eraseblock handler
* @buf: eraseblock header to check
*
* Returns eraseblock header status.
*/
int
nor_check_eb_hdr(struct chfs_ebh *ebh, void *buf)
{
uint32_t magic, crc, hdr_crc;
struct chfs_eb_hdr *ebhdr = buf;
le32 lid_save;
//check is there a header
if (check_pattern((void *) &ebhdr->ec_hdr,
0xFF, 0, CHFS_EB_EC_HDR_SIZE)) {
dbg_ebh("no header found\n");
return EBHDR_LEB_NO_HDR;
}
// check magic
magic = le32toh(ebhdr->ec_hdr.magic);
if (magic != CHFS_MAGIC_BITMASK) {
dbg_ebh("bad magic bitmask(exp: %x found %x)\n",
CHFS_MAGIC_BITMASK, magic);
return EBHDR_LEB_BADMAGIC;
}
// check CRC_EC
hdr_crc = le32toh(ebhdr->ec_hdr.crc_ec);
crc = crc32(0, (uint8_t *) &ebhdr->ec_hdr + 8, 4);
if (hdr_crc != crc) {
dbg_ebh("bad crc_ec found\n");
return EBHDR_LEB_BADCRC;
}
/* check if the PEB is free: magic, crc_ec and erase_cnt is good and
* everything else is FFF..
*/
if (check_pattern((void *) &ebhdr->u.nor_hdr, 0xFF, 0,
CHFS_EB_HDR_NOR_SIZE)) {
dbg_ebh("free peb found\n");
return EBHDR_LEB_FREE;
}
// check invalidated (CRC == LID == 0)
if (ebhdr->u.nor_hdr.crc == 0 && ebhdr->u.nor_hdr.lid == 0) {
dbg_ebh("invalidated ebhdr found\n");
return EBHDR_LEB_INVALIDATED;
}
// check CRC
hdr_crc = le32toh(ebhdr->u.nor_hdr.crc);
lid_save = ebhdr->u.nor_hdr.lid;
// mark lid as not dirty for crc calc
ebhdr->u.nor_hdr.lid = ebhdr->u.nor_hdr.lid | htole32(
CHFS_LID_NOT_DIRTY_BIT);
crc = crc32(0, (uint8_t *) &ebhdr->u.nor_hdr + 4,
CHFS_EB_HDR_NOR_SIZE - 4);
// restore the original lid value in ebh
ebhdr->u.nor_hdr.lid = lid_save;
if (crc != hdr_crc) {
dbg_ebh("bad crc found\n");
return EBHDR_LEB_BADCRC;
}
// check dirty
if (!(le32toh(lid_save) & CHFS_LID_NOT_DIRTY_BIT)) {
dbg_ebh("dirty ebhdr found\n");
return EBHDR_LEB_DIRTY;
}
return EBHDR_LEB_OK;
}
/**
* nand_check_eb_hdr - check ereaseblock header read from NAND flash
*
* @ebh: chfs eraseblock handler
* @buf: eraseblock header to check
*
* Returns eraseblock header status.
*/
int
nand_check_eb_hdr(struct chfs_ebh *ebh, void *buf)
{
uint32_t magic, crc, hdr_crc;
struct chfs_eb_hdr *ebhdr = buf;
//check is there a header
if (check_pattern((void *) &ebhdr->ec_hdr,
0xFF, 0, CHFS_EB_EC_HDR_SIZE)) {
dbg_ebh("no header found\n");
return EBHDR_LEB_NO_HDR;
}
// check magic
magic = le32toh(ebhdr->ec_hdr.magic);
if (magic != CHFS_MAGIC_BITMASK) {
dbg_ebh("bad magic bitmask(exp: %x found %x)\n",
CHFS_MAGIC_BITMASK, magic);
return EBHDR_LEB_BADMAGIC;
}
// check CRC_EC
hdr_crc = le32toh(ebhdr->ec_hdr.crc_ec);
crc = crc32(0, (uint8_t *) &ebhdr->ec_hdr + 8, 4);
if (hdr_crc != crc) {
dbg_ebh("bad crc_ec found\n");
return EBHDR_LEB_BADCRC;
}
/* check if the PEB is free: magic, crc_ec and erase_cnt is good and
* everything else is FFF..
*/
if (check_pattern((void *) &ebhdr->u.nand_hdr, 0xFF, 0,
CHFS_EB_HDR_NAND_SIZE)) {
dbg_ebh("free peb found\n");
return EBHDR_LEB_FREE;
}
// check CRC
hdr_crc = le32toh(ebhdr->u.nand_hdr.crc);
crc = crc32(0, (uint8_t *) &ebhdr->u.nand_hdr + 4,
CHFS_EB_HDR_NAND_SIZE - 4);
if (crc != hdr_crc) {
dbg_ebh("bad crc found\n");
return EBHDR_LEB_BADCRC;
}
return EBHDR_LEB_OK;
}
/**
* nor_mark_eb_hdr_dirty_flash- mark ereaseblock header dirty on NOR flash
*
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number
* @lid: leb id (it's bit number 31 will be set to 0)
*
* It pulls the CHFS_LID_NOT_DIRTY_BIT to zero on flash.
*
* Returns zero in case of success, error code in case of fail.
*/
int
nor_mark_eb_hdr_dirty_flash(struct chfs_ebh *ebh, int pebnr, int lid)
{
int ret;
size_t retlen;
off_t ofs;
/* mark leb id dirty */
lid = htole32(lid & CHFS_LID_DIRTY_BIT_MASK);
/* calculate position */
ofs = pebnr * ebh->flash_if->erasesize + CHFS_EB_EC_HDR_SIZE
+ CHFS_GET_MEMBER_POS(struct chfs_nor_eb_hdr , lid);
ret = flash_write(ebh->flash_dev, ofs, sizeof(lid), &retlen,
(unsigned char *) &lid);
if (ret || retlen != sizeof(lid)) {
chfs_err("can't mark peb dirty");
return ret;
}
return 0;
}
/**
* nor_invalidate_eb_hdr - invalidate ereaseblock header on NOR flash
*
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number
*
* Sets crc and lip field to zero.
* Returns zero in case of success, error code in case of fail.
*/
int
nor_invalidate_eb_hdr(struct chfs_ebh *ebh, int pebnr)
{
int ret;
size_t retlen;
off_t ofs;
char zero_buf[CHFS_INVALIDATE_SIZE];
/* fill with zero */
memset(zero_buf, 0x0, CHFS_INVALIDATE_SIZE);
/* calculate position (!!! lid is directly behind crc !!!) */
ofs = pebnr * ebh->flash_if->erasesize + CHFS_EB_EC_HDR_SIZE
+ CHFS_GET_MEMBER_POS(struct chfs_nor_eb_hdr, crc);
ret = flash_write(ebh->flash_dev,
ofs, CHFS_INVALIDATE_SIZE, &retlen,
(unsigned char *) &zero_buf);
if (ret || retlen != CHFS_INVALIDATE_SIZE) {
chfs_err("can't invalidate peb");
return ret;
}
return 0;
}
/**
* mark_eb_hdr_free - free ereaseblock header on NOR or NAND flash
*
* @ebh: chfs eraseblock handler
* @pebnr: eraseblock number
* @ec: erase counter of PEB
*
* Write out the magic and erase counter to the physical eraseblock.
* Returns zero in case of success, error code in case of fail.
*/
int
mark_eb_hdr_free(struct chfs_ebh *ebh, int pebnr, int ec)
{
int ret, crc;
size_t retlen;
off_t ofs;
struct chfs_eb_hdr *ebhdr;
ebhdr = kmem_alloc(sizeof(struct chfs_eb_hdr), KM_SLEEP);
ebhdr->ec_hdr.magic = htole32(CHFS_MAGIC_BITMASK);
ebhdr->ec_hdr.erase_cnt = htole32(ec);
crc = crc32(0, (uint8_t *) &ebhdr->ec_hdr + 8, 4);
ebhdr->ec_hdr.crc_ec = htole32(crc);
ofs = pebnr * ebh->flash_if->erasesize;
KASSERT(sizeof(ebhdr->ec_hdr) == CHFS_EB_EC_HDR_SIZE);
ret = flash_write(ebh->flash_dev,
ofs, CHFS_EB_EC_HDR_SIZE, &retlen,
(unsigned char *) &ebhdr->ec_hdr);
if (ret || retlen != CHFS_EB_EC_HDR_SIZE) {
chfs_err("can't mark peb as free: %d\n", pebnr);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return ret;
}
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return 0;
}
/*****************************************************************************/
/* End of Flash specific operations */
/*****************************************************************************/
/*****************************************************************************/
/* Lock Tree */
/*****************************************************************************/
int
ltree_entry_cmp(struct chfs_ltree_entry *le1,
struct chfs_ltree_entry *le2)
{
return (le1->lnr - le2->lnr);
}
/* Generate functions for Lock tree's red-black tree */
RB_PROTOTYPE( ltree_rbtree, chfs_ltree_entry, rb, ltree_entry_cmp);
RB_GENERATE( ltree_rbtree, chfs_ltree_entry, rb, ltree_entry_cmp);
/**
* ltree_lookup - looks up a logical eraseblock in the lock tree
* @ebh: chfs eraseblock handler
* @lid: identifier of the logical eraseblock
*
* This function returns a pointer to the wanted &struct chfs_ltree_entry
* if the logical eraseblock is in the lock tree, so it is locked, NULL
* otherwise.
* @ebh->ltree_lock has to be locked!
*/
static struct chfs_ltree_entry *
ltree_lookup(struct chfs_ebh *ebh, int lnr)
{
struct chfs_ltree_entry le, *result;
le.lnr = lnr;
result = RB_FIND(ltree_rbtree, &ebh->ltree, &le);
return result;
}
/**
* ltree_add_entry - add an entry to the lock tree
* @ebh: chfs eraseblock handler
* @lnr: identifier of the logical eraseblock
*
* This function adds a new logical eraseblock entry identified with @lnr to the
* lock tree. If the entry is already in the tree, it increases the user
* counter.
* Returns NULL if can not allocate memory for lock tree entry, or a pointer
* to the inserted entry otherwise.
*/
static struct chfs_ltree_entry *
ltree_add_entry(struct chfs_ebh *ebh, int lnr)
{
struct chfs_ltree_entry *le, *result;
le = kmem_alloc(sizeof(struct chfs_ltree_entry), KM_SLEEP);
le->lnr = lnr;
le->users = 1;
rw_init(&le->mutex);
//dbg_ebh("enter ltree lock\n");
mutex_enter(&ebh->ltree_lock);
//dbg_ebh("insert\n");
result = RB_INSERT(ltree_rbtree, &ebh->ltree, le);
//dbg_ebh("inserted\n");
if (result) {
//The entry is already in the tree
result->users++;
kmem_free(le, sizeof(struct chfs_ltree_entry));
}
else {
result = le;
}
mutex_exit(&ebh->ltree_lock);
return result;
}
/**
* leb_read_lock - lock a logical eraseblock for read
* @ebh: chfs eraseblock handler
* @lnr: identifier of the logical eraseblock
*
* Returns zero in case of success, error code in case of fail.
*/
static int
leb_read_lock(struct chfs_ebh *ebh, int lnr)
{
struct chfs_ltree_entry *le;
le = ltree_add_entry(ebh, lnr);
if (!le)
return ENOMEM;
rw_enter(&le->mutex, RW_READER);
return 0;
}
/**
* leb_read_unlock - unlock a logical eraseblock from read
* @ebh: chfs eraseblock handler
* @lnr: identifier of the logical eraseblock
*
* This function unlocks a logical eraseblock from read and delete it from the
* lock tree is there are no more users of it.
*/
static void
leb_read_unlock(struct chfs_ebh *ebh, int lnr)
{
struct chfs_ltree_entry *le;
mutex_enter(&ebh->ltree_lock);
//dbg_ebh("LOCK: ebh->ltree_lock spin locked in leb_read_unlock()\n");
le = ltree_lookup(ebh, lnr);
if (!le)
goto out;
le->users -= 1;
KASSERT(le->users >= 0);
rw_exit(&le->mutex);
if (le->users == 0) {
le = RB_REMOVE(ltree_rbtree, &ebh->ltree, le);
if (le) {
KASSERT(!rw_lock_held(&le->mutex));
rw_destroy(&le->mutex);
kmem_free(le, sizeof(struct chfs_ltree_entry));
}
}
out:
mutex_exit(&ebh->ltree_lock);
//dbg_ebh("UNLOCK: ebh->ltree_lock spin unlocked in leb_read_unlock()\n");
}
/**
* leb_write_lock - lock a logical eraseblock for write
* @ebh: chfs eraseblock handler
* @lnr: identifier of the logical eraseblock
*
* Returns zero in case of success, error code in case of fail.
*/
static int
leb_write_lock(struct chfs_ebh *ebh, int lnr)
{
struct chfs_ltree_entry *le;
le = ltree_add_entry(ebh, lnr);
if (!le)
return ENOMEM;
rw_enter(&le->mutex, RW_WRITER);
return 0;
}
/**
* leb_write_unlock - unlock a logical eraseblock from write
* @ebh: chfs eraseblock handler
* @lnr: identifier of the logical eraseblock
*
* This function unlocks a logical eraseblock from write and delete it from the
* lock tree is there are no more users of it.
*/
static void
leb_write_unlock(struct chfs_ebh *ebh, int lnr)
{
struct chfs_ltree_entry *le;
mutex_enter(&ebh->ltree_lock);
//dbg_ebh("LOCK: ebh->ltree_lock spin locked in leb_write_unlock()\n");
le = ltree_lookup(ebh, lnr);
if (!le)
goto out;
le->users -= 1;
KASSERT(le->users >= 0);
rw_exit(&le->mutex);
if (le->users == 0) {
RB_REMOVE(ltree_rbtree, &ebh->ltree, le);
KASSERT(!rw_lock_held(&le->mutex));
rw_destroy(&le->mutex);
kmem_free(le, sizeof(struct chfs_ltree_entry));
}
out:
mutex_exit(&ebh->ltree_lock);
//dbg_ebh("UNLOCK: ebh->ltree_lock spin unlocked in leb_write_unlock()\n");
}
/*****************************************************************************/
/* End of Lock Tree */
/*****************************************************************************/
/*****************************************************************************/
/* Erase related operations */
/*****************************************************************************/
/**
* If the first argument is smaller than the second, the function
* returns a value smaller than zero. If they are equal, the function re-
* turns zero. Otherwise, it should return a value greater than zero.
*/
int
peb_in_use_cmp(struct chfs_peb *peb1, struct chfs_peb *peb2)
{
return (peb1->pebnr - peb2->pebnr);
}
int
peb_free_cmp(struct chfs_peb *peb1, struct chfs_peb *peb2)
{
int comp;
comp = peb1->erase_cnt - peb2->erase_cnt;
if (0 == comp)
comp = peb1->pebnr - peb2->pebnr;
return comp;
}
/* Generate functions for in use PEB's red-black tree */
RB_PROTOTYPE(peb_in_use_rbtree, chfs_peb, u.rb, peb_in_use_cmp);
RB_GENERATE(peb_in_use_rbtree, chfs_peb, u.rb, peb_in_use_cmp);
RB_PROTOTYPE(peb_free_rbtree, chfs_peb, u.rb, peb_free_cmp);
RB_GENERATE(peb_free_rbtree, chfs_peb, u.rb, peb_free_cmp);
/**
* add_peb_to_erase_queue: adds a PEB to to_erase/fully_erased queue
* @ebh - chfs eraseblock handler
* @pebnr - physical eraseblock's number
* @ec - erase counter of PEB
* @queue: the queue to add to
*
* This function adds a PEB to the erase queue specified by @queue.
* The @ebh->erase_lock must be locked before using this.
* Returns zero in case of success, error code in case of fail.
*/
int
add_peb_to_erase_queue(struct chfs_ebh *ebh, int pebnr, int ec,
struct peb_queue *queue)
{
struct chfs_peb *peb;
peb = kmem_alloc(sizeof(struct chfs_peb), KM_SLEEP);
peb->erase_cnt = ec;
peb->pebnr = pebnr;
TAILQ_INSERT_TAIL(queue, peb, u.queue);
return 0;
}
//TODO
/**
* find_peb_in_use - looks up a PEB in the RB-tree of used blocks
* @ebh - chfs eraseblock handler
*
* This function returns a pointer to the PEB found in the tree,
* NULL otherwise.
* The @ebh->erase_lock must be locked before using this.
*/
struct chfs_peb *
find_peb_in_use(struct chfs_ebh *ebh, int pebnr)
{
struct chfs_peb peb, *result;
peb.pebnr = pebnr;
result = RB_FIND(peb_in_use_rbtree, &ebh->in_use, &peb);
return result;
}
/**
* add_peb_to_free - adds a PEB to the RB-tree of free PEBs
* @ebh - chfs eraseblock handler
* @pebnr - physical eraseblock's number
* @ec - erase counter of PEB
*
*
* This function adds a physical eraseblock to the RB-tree of free PEBs
* stored in the @ebh. The key is the erase counter and pebnr.
* The @ebh->erase_lock must be locked before using this.
* Returns zero in case of success, error code in case of fail.
*/
int
add_peb_to_free(struct chfs_ebh *ebh, int pebnr, int ec)
{
struct chfs_peb *peb, *result;
peb = kmem_alloc(sizeof(struct chfs_peb), KM_SLEEP);
peb->erase_cnt = ec;
peb->pebnr = pebnr;
result = RB_INSERT(peb_free_rbtree, &ebh->free, peb);
if (result)
return 1;
return 0;
}
/**
* add_peb_to_in_use - adds a PEB to the RB-tree of used PEBs
* @ebh - chfs eraseblock handler
* @pebnr - physical eraseblock's number
* @ec - erase counter of PEB
*
*
* This function adds a physical eraseblock to the RB-tree of used PEBs
* stored in the @ebh. The key is pebnr.
* The @ebh->erase_lock must be locked before using this.
* Returns zero in case of success, error code in case of fail.
*/
int
add_peb_to_in_use(struct chfs_ebh *ebh, int pebnr, int ec)
{
struct chfs_peb *peb, *result;
peb = kmem_alloc(sizeof(struct chfs_peb), KM_SLEEP);
peb->erase_cnt = ec;
peb->pebnr = pebnr;
result = RB_INSERT(peb_in_use_rbtree, &ebh->in_use, peb);
if (result)
return 1;
return 0;
}
/**
* erase_callback - callback function for flash erase
* @ei: erase information
*/
void
erase_callback(struct flash_erase_instruction *ei)
{
int err;
struct chfs_erase_info_priv *priv = (void *) ei->ei_priv;
//dbg_ebh("ERASE_CALLBACK() CALLED\n");
struct chfs_ebh *ebh = priv->ebh;
struct chfs_peb *peb = priv->peb;
peb->erase_cnt += 1;
if (ei->ei_state == FLASH_ERASE_DONE) {
/* Write out erase counter */
err = ebh->ops->mark_eb_hdr_free(ebh,
peb->pebnr, peb->erase_cnt);
if (err) {
/* cannot mark PEB as free,so erase it again */
chfs_err(
"cannot mark eraseblock as free, PEB: %d\n",
peb->pebnr);
mutex_enter(&ebh->erase_lock);
/*dbg_ebh("LOCK: ebh->erase_lock spin locked in erase_callback() "
"after mark ebhdr free\n");*/
add_peb_to_erase_queue(ebh, peb->pebnr, peb->erase_cnt,
&ebh->to_erase);
mutex_exit(&ebh->erase_lock);
/*dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in erase_callback() "
"after mark ebhdr free\n");*/
kmem_free(peb, sizeof(struct chfs_peb));
return;
}
mutex_enter(&ebh->erase_lock);
/*dbg_ebh("LOCK: ebh->erase_lock spin locked in erase_callback()\n");*/
err = add_peb_to_free(ebh, peb->pebnr, peb->erase_cnt);
mutex_exit(&ebh->erase_lock);
/*dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in erase_callback()\n");*/
kmem_free(peb, sizeof(struct chfs_peb));
} else {
/*
* Erase is finished, but there was a problem,
* so erase PEB again
*/
chfs_err("erase failed, state is: 0x%x\n", ei->ei_state);
add_peb_to_erase_queue(ebh, peb->pebnr, peb->erase_cnt, &ebh->to_erase);
kmem_free(peb, sizeof(struct chfs_peb));
}
}
/**
* free_peb: free a PEB
* @ebh: chfs eraseblock handler
*
* This function erases the first physical eraseblock from one of the erase
* lists and adds to the RB-tree of free PEBs.
* Returns zero in case of succes, error code in case of fail.
*/
int
free_peb(struct chfs_ebh *ebh)
{
int err, retries = 0;
off_t ofs;
struct chfs_peb *peb = NULL;
struct flash_erase_instruction *ei;
KASSERT(mutex_owned(&ebh->erase_lock));
if (!TAILQ_EMPTY(&ebh->fully_erased)) {
//dbg_ebh("[FREE PEB] got a fully erased block\n");
peb = TAILQ_FIRST(&ebh->fully_erased);
TAILQ_REMOVE(&ebh->fully_erased, peb, u.queue);
err = ebh->ops->mark_eb_hdr_free(ebh,
peb->pebnr, peb->erase_cnt);
if (err) {
goto out_free;
}
err = add_peb_to_free(ebh, peb->pebnr, peb->erase_cnt);
goto out_free;
}
/* Erase PEB */
//dbg_ebh("[FREE PEB] eraseing a block\n");
peb = TAILQ_FIRST(&ebh->to_erase);
TAILQ_REMOVE(&ebh->to_erase, peb, u.queue);
mutex_exit(&ebh->erase_lock);
//dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in free_peb()\n");
ofs = peb->pebnr * ebh->flash_if->erasesize;
/* XXX where do we free this? */
ei = kmem_alloc(sizeof(struct flash_erase_instruction)
+ sizeof(struct chfs_erase_info_priv), KM_SLEEP);
retry:
memset(ei, 0, sizeof(*ei));
// ei->ei_if = ebh->flash_if;
ei->ei_addr = ofs;
ei->ei_len = ebh->flash_if->erasesize;
ei->ei_callback = erase_callback;
ei->ei_priv = (unsigned long) (&ei[1]);
((struct chfs_erase_info_priv *) ei->ei_priv)->ebh = ebh;
((struct chfs_erase_info_priv *) ei->ei_priv)->peb = peb;
err = flash_erase(ebh->flash_dev, ei);
dbg_ebh("erased peb: %d\n", peb->pebnr);
/* einval would mean we did something wrong */
KASSERT(err != EINVAL);
if (err) {
dbg_ebh("errno: %d, ei->ei_state: %d\n", err, ei->ei_state);
if (CHFS_MAX_GET_PEB_RETRIES < ++retries &&
ei->ei_state == FLASH_ERASE_FAILED) {
/* The block went bad mark it */
dbg_ebh("ebh markbad! 0x%jx\n", (uintmax_t )ofs);
err = flash_block_markbad(ebh->flash_dev, ofs);
if (!err) {
ebh->peb_nr--;
}
goto out;
}
chfs_err("can not erase PEB: %d, try again\n", peb->pebnr);
goto retry;
}
out:
/* lock the erase_lock, because it was locked
* when the function was called */
mutex_enter(&ebh->erase_lock);
return err;
out_free:
kmem_free(peb, sizeof(struct chfs_peb));
return err;
}
/**
* release_peb - schedule an erase for the PEB
* @ebh: chfs eraseblock handler
* @pebnr: physical eraseblock number
*
* This function get the peb identified by @pebnr from the in_use RB-tree of
* @ebh, removes it and schedule an erase for it.
*
* Returns zero on success, error code in case of fail.
*/
int
release_peb(struct chfs_ebh *ebh, int pebnr)
{
int err = 0;
struct chfs_peb *peb;
mutex_enter(&ebh->erase_lock);
//dbg_ebh("LOCK: ebh->erase_lock spin locked in release_peb()\n");
peb = find_peb_in_use(ebh, pebnr);
if (!peb) {
chfs_err("LEB is mapped, but is not in the 'in_use' "
"tree of ebh\n");
goto out_unlock;
}
err = add_peb_to_erase_queue(ebh, peb->pebnr, peb->erase_cnt,
&ebh->to_erase);
if (err)
goto out_unlock;
RB_REMOVE(peb_in_use_rbtree, &ebh->in_use, peb);
out_unlock:
mutex_exit(&ebh->erase_lock);
//dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in release_peb()"
// " at out_unlock\n");
return err;
}
/**
* erase_thread - background thread for erasing PEBs
* @data: pointer to the eraseblock handler
*/
/*void
erase_thread(void *data)
{
struct chfs_ebh *ebh = data;
dbg_ebh("erase thread started\n");
while (ebh->bg_erase.eth_running) {
int err;
mutex_enter(&ebh->erase_lock);
dbg_ebh("LOCK: ebh->erase_lock spin locked in erase_thread()\n");
if (TAILQ_EMPTY(&ebh->to_erase) && TAILQ_EMPTY(&ebh->fully_erased)) {
dbg_ebh("thread has nothing to do\n");
mutex_exit(&ebh->erase_lock);
mutex_enter(&ebh->bg_erase.eth_thread_mtx);
cv_timedwait_sig(&ebh->bg_erase.eth_wakeup,
&ebh->bg_erase.eth_thread_mtx, mstohz(100));
mutex_exit(&ebh->bg_erase.eth_thread_mtx);
dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in erase_thread()\n");
continue;
}
mutex_exit(&ebh->erase_lock);
dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in erase_thread()\n");
err = free_peb(ebh);
if (err)
chfs_err("freeing PEB failed in the background thread: %d\n", err);
}
dbg_ebh("erase thread stopped\n");
kthread_exit(0);
}*/
/**
* erase_thread - background thread for erasing PEBs
* @data: pointer to the eraseblock handler
*/
void
erase_thread(void *data) {
dbg_ebh("[EBH THREAD] erase thread started\n");
struct chfs_ebh *ebh = data;
int err;
mutex_enter(&ebh->erase_lock);
while (ebh->bg_erase.eth_running) {
if (TAILQ_EMPTY(&ebh->to_erase) &&
TAILQ_EMPTY(&ebh->fully_erased)) {
cv_timedwait_sig(&ebh->bg_erase.eth_wakeup,
&ebh->erase_lock, mstohz(100));
} else {
/* XXX exiting this mutex is a bit odd here as
* free_peb instantly reenters it...
*/
err = free_peb(ebh);
mutex_exit(&ebh->erase_lock);
if (err) {
chfs_err("freeing PEB failed in the"
" background thread: %d\n", err);
}
mutex_enter(&ebh->erase_lock);
}
}
mutex_exit(&ebh->erase_lock);
dbg_ebh("[EBH THREAD] erase thread stopped\n");
kthread_exit(0);
}
/**
* erase_thread_start - init and start erase thread
* @ebh: eraseblock handler
*/
static void
erase_thread_start(struct chfs_ebh *ebh)
{
cv_init(&ebh->bg_erase.eth_wakeup, "ebheracv");
ebh->bg_erase.eth_running = true;
kthread_create(PRI_NONE, KTHREAD_MPSAFE | KTHREAD_MUSTJOIN, NULL,
erase_thread, ebh, &ebh->bg_erase.eth_thread, "ebherase");
}
/**
* erase_thread_stop - stop background erase thread
* @ebh: eraseblock handler
*/
static void
erase_thread_stop(struct chfs_ebh *ebh)
{
ebh->bg_erase.eth_running = false;
cv_signal(&ebh->bg_erase.eth_wakeup);
dbg_ebh("[EBH THREAD STOP] signaled\n");
kthread_join(ebh->bg_erase.eth_thread);
#ifdef BROKEN_KTH_JOIN
kpause("chfsebhjointh", false, mstohz(1000), NULL);
#endif
cv_destroy(&ebh->bg_erase.eth_wakeup);
}
/*****************************************************************************/
/* End of Erase related operations */
/*****************************************************************************/
/*****************************************************************************/
/* Scan related operations */
/*****************************************************************************/
int
scan_leb_used_cmp(struct chfs_scan_leb *sleb1, struct chfs_scan_leb *sleb2)
{
return (sleb1->lnr - sleb2->lnr);
}
RB_PROTOTYPE(scan_leb_used_rbtree, chfs_scan_leb, u.rb, scan_leb_used_cmp);
RB_GENERATE(scan_leb_used_rbtree, chfs_scan_leb, u.rb, scan_leb_used_cmp);
/**
* scan_add_to_queue - adds a physical eraseblock to one of the
* eraseblock queue
* @si: chfs scanning information
* @pebnr: physical eraseblock number
* @erase_cnt: erase counter of the physical eraseblock
* @list: the list to add to
*
* This function adds a physical eraseblock to one of the lists in the scanning
* information.
* Returns zero in case of success, negative error code in case of fail.
*/
static int
scan_add_to_queue(struct chfs_scan_info *si, int pebnr, int erase_cnt,
struct scan_leb_queue *queue)
{
struct chfs_scan_leb *sleb;
sleb = kmem_alloc(sizeof(struct chfs_scan_leb), KM_SLEEP);
sleb->pebnr = pebnr;
sleb->erase_cnt = erase_cnt;
TAILQ_INSERT_TAIL(queue, sleb, u.queue);
return 0;
}
/*
* nor_scan_add_to_used - add a physical eraseblock to the
* used tree of scan info
* @ebh: chfs eraseblock handler
* @si: chfs scanning information
* @ebhdr: eraseblock header
* @pebnr: physical eraseblock number
* @leb_status: the status of the PEB's eraseblock header
*
* This function adds a PEB to the used tree of the scanning information.
* It handles the situations if there are more physical eraseblock referencing
* to the same logical eraseblock.
* Returns zero in case of success, error code in case of fail.
*/
int
nor_scan_add_to_used(struct chfs_ebh *ebh, struct chfs_scan_info *si,
struct chfs_eb_hdr *ebhdr, int pebnr, int leb_status)
{
int err, lnr, ec;
struct chfs_scan_leb *sleb, *old;
lnr = CHFS_GET_LID(ebhdr->u.nor_hdr.lid);
ec = le32toh(ebhdr->ec_hdr.erase_cnt);
sleb = kmem_alloc(sizeof(struct chfs_scan_leb), KM_SLEEP);
sleb->erase_cnt = ec;
sleb->lnr = lnr;
sleb->pebnr = pebnr;
sleb->info = leb_status;
old = RB_INSERT(scan_leb_used_rbtree, &si->used, sleb);
if (old) {
kmem_free(sleb, sizeof(struct chfs_scan_leb));
/* There is already an eraseblock in the used tree */
/* If the new one is bad */
if (EBHDR_LEB_DIRTY == leb_status &&
EBHDR_LEB_OK == old->info) {
return scan_add_to_queue(si, pebnr, ec, &si->erase);
} else {
err = scan_add_to_queue(si, old->pebnr,
old->erase_cnt, &si->erase);
if (err) {
return err;
}
old->erase_cnt = ec;
old->lnr = lnr;
old->pebnr = pebnr;
old->info = leb_status;
return 0;
}
}
return 0;
}
/**
* nor_process eb -read the headers from NOR flash, check them and add to
* the scanning information
* @ebh: chfs eraseblock handler
* @si: chfs scanning information
* @pebnr: physical eraseblock number
*
* Returns zero in case of success, error code in case of fail.
*/
int
nor_process_eb(struct chfs_ebh *ebh, struct chfs_scan_info *si,
int pebnr, struct chfs_eb_hdr *ebhdr)
{
int err, erase_cnt, leb_status;
err = ebh->ops->read_eb_hdr(ebh, pebnr, ebhdr);
if (err)
return err;
erase_cnt = le32toh(ebhdr->ec_hdr.erase_cnt);
dbg_ebh("erase_cnt: %d\n", erase_cnt);
leb_status = ebh->ops->check_eb_hdr(ebh, ebhdr);
if (EBHDR_LEB_BADMAGIC == leb_status ||
EBHDR_LEB_BADCRC == leb_status) {
err = scan_add_to_queue(si, pebnr, erase_cnt, &si->corrupted);
return err;
}
else if (EBHDR_LEB_FREE == leb_status) {
err = scan_add_to_queue(si, pebnr, erase_cnt, &si->free);
goto count_mean;
}
else if (EBHDR_LEB_NO_HDR == leb_status) {
err = scan_add_to_queue(si, pebnr, erase_cnt, &si->erased);
return err;
}
else if (EBHDR_LEB_INVALIDATED == leb_status) {
err = scan_add_to_queue(si, pebnr, erase_cnt, &si->erase);
return err;
}
err = nor_scan_add_to_used(ebh, si, ebhdr, pebnr, leb_status);
if (err)
return err;
count_mean:
si->sum_of_ec += erase_cnt;
si->num_of_eb++;
return err;
}
/*
* nand_scan_add_to_used - add a physical eraseblock to the
* used tree of scan info
* @ebh: chfs eraseblock handler
* @si: chfs scanning information
* @ebhdr: eraseblock header
* @pebnr: physical eraseblock number
* @leb_status: the status of the PEB's eraseblock header
*
* This function adds a PEB to the used tree of the scanning information.
* It handles the situations if there are more physical eraseblock referencing
* to the same logical eraseblock.
* Returns zero in case of success, error code in case of fail.
*/
int
nand_scan_add_to_used(struct chfs_ebh *ebh, struct chfs_scan_info *si,
struct chfs_eb_hdr *ebhdr, int pebnr)
{
int err, lnr, ec;
struct chfs_scan_leb *sleb, *old;
uint64_t serial = le64toh(ebhdr->u.nand_hdr.serial);
lnr = CHFS_GET_LID(ebhdr->u.nor_hdr.lid);
ec = le32toh(ebhdr->ec_hdr.erase_cnt);
sleb = kmem_alloc(sizeof(struct chfs_scan_leb), KM_SLEEP);
sleb->erase_cnt = ec;
sleb->lnr = lnr;
sleb->pebnr = pebnr;
sleb->info = serial;
old = RB_INSERT(scan_leb_used_rbtree, &si->used, sleb);
if (old) {
kmem_free(sleb, sizeof(struct chfs_scan_leb));
/* There is already an eraseblock in the used tree */
/* If the new one is bad */
if (serial < old->info)
return scan_add_to_queue(si, pebnr, ec, &si->erase);
else {
err = scan_add_to_queue(si,
old->pebnr, old->erase_cnt, &si->erase);
if (err)
return err;
old->erase_cnt = ec;
old->lnr = lnr;
old->pebnr = pebnr;
old->info = serial;
return 0;
}
}
return 0;
}
/**
* nand_process eb -read the headers from NAND flash, check them and add to the
* scanning information
* @ebh: chfs eraseblock handler
* @si: chfs scanning information
* @pebnr: physical eraseblock number
*
* Returns zero in case of success, error code in case of fail.
*/
int
nand_process_eb(struct chfs_ebh *ebh, struct chfs_scan_info *si,
int pebnr, struct chfs_eb_hdr *ebhdr)
{
int err, erase_cnt, leb_status;
uint64_t max_serial;
/* isbad() is defined on some ancient platforms, heh */
bool is_bad;
/* Check block is bad */
err = flash_block_isbad(ebh->flash_dev,
pebnr * ebh->flash_if->erasesize, &is_bad);
if (err) {
chfs_err("checking block is bad failed\n");
return err;
}
if (is_bad) {
si->bad_peb_cnt++;
return 0;
}
err = ebh->ops->read_eb_hdr(ebh, pebnr, ebhdr);
if (err)
return err;
erase_cnt = le32toh(ebhdr->ec_hdr.erase_cnt);
leb_status = ebh->ops->check_eb_hdr(ebh, ebhdr);
if (EBHDR_LEB_BADMAGIC == leb_status ||
EBHDR_LEB_BADCRC == leb_status) {
err = scan_add_to_queue(si, pebnr, erase_cnt, &si->corrupted);
return err;
}
else if (EBHDR_LEB_FREE == leb_status) {
err = scan_add_to_queue(si, pebnr, erase_cnt, &si->free);
goto count_mean;
}
else if (EBHDR_LEB_NO_HDR == leb_status) {
err = scan_add_to_queue(si, pebnr, erase_cnt, &si->erased);
return err;
}
err = nand_scan_add_to_used(ebh, si, ebhdr, pebnr);
if (err)
return err;
max_serial = le64toh(ebhdr->u.nand_hdr.serial);
if (max_serial > *ebh->max_serial) {
*ebh->max_serial = max_serial;
}
count_mean:
si->sum_of_ec += erase_cnt;
si->num_of_eb++;
return err;
}
/**
* chfs_scan - scans the media and returns informations about it
* @ebh: chfs eraseblock handler
*
* This function scans through the media and returns information about it or if
* it fails NULL will be returned.
*/
struct chfs_scan_info *
chfs_scan(struct chfs_ebh *ebh)
{
struct chfs_scan_info *si;
struct chfs_eb_hdr *ebhdr;
int pebnr, err;
si = kmem_alloc(sizeof(*si), KM_SLEEP);
TAILQ_INIT(&si->corrupted);
TAILQ_INIT(&si->free);
TAILQ_INIT(&si->erase);
TAILQ_INIT(&si->erased);
RB_INIT(&si->used);
si->bad_peb_cnt = 0;
si->num_of_eb = 0;
si->sum_of_ec = 0;
ebhdr = kmem_alloc(sizeof(*ebhdr), KM_SLEEP);
for (pebnr = 0; pebnr < ebh->peb_nr; pebnr++) {
dbg_ebh("processing PEB %d\n", pebnr);
err = ebh->ops->process_eb(ebh, si, pebnr, ebhdr);
if (err < 0)
goto out_ebhdr;
}
kmem_free(ebhdr, sizeof(*ebhdr));
dbg_ebh("[CHFS_SCAN] scanning information collected\n");
return si;
out_ebhdr:
kmem_free(ebhdr, sizeof(*ebhdr));
kmem_free(si, sizeof(*si));
return NULL;
}
/**
* scan_info_destroy - frees all lists and trees in the scanning information
* @si: the scanning information
*/
void
scan_info_destroy(struct chfs_scan_info *si)
{
EBH_QUEUE_DESTROY(&si->corrupted,
struct chfs_scan_leb, u.queue);
EBH_QUEUE_DESTROY(&si->erase,
struct chfs_scan_leb, u.queue);
EBH_QUEUE_DESTROY(&si->erased,
struct chfs_scan_leb, u.queue);
EBH_QUEUE_DESTROY(&si->free,
struct chfs_scan_leb, u.queue);
EBH_TREE_DESTROY(scan_leb_used_rbtree,
&si->used, struct chfs_scan_leb);
kmem_free(si, sizeof(*si));
dbg_ebh("[SCAN_INFO_DESTROY] scanning information destroyed\n");
}
/**
* scan_media - scan media
*
* @ebh - chfs eraseblock handler
*
* Returns zero in case of success, error code in case of fail.
*/
int
scan_media(struct chfs_ebh *ebh)
{
int err, i, avg_ec;
struct chfs_scan_info *si;
struct chfs_scan_leb *sleb;
si = chfs_scan(ebh);
/*
* Process the scan info, manage the eraseblock lists
*/
mutex_init(&ebh->ltree_lock, MUTEX_DEFAULT, IPL_NONE);
mutex_init(&ebh->erase_lock, MUTEX_DEFAULT, IPL_NONE);
RB_INIT(&ebh->ltree);
RB_INIT(&ebh->free);
RB_INIT(&ebh->in_use);
TAILQ_INIT(&ebh->to_erase);
TAILQ_INIT(&ebh->fully_erased);
mutex_init(&ebh->alc_mutex, MUTEX_DEFAULT, IPL_NONE);
ebh->peb_nr -= si->bad_peb_cnt;
/*
* Create background thread for erasing
*/
erase_thread_start(ebh);
ebh->lmap = kmem_alloc(ebh->peb_nr * sizeof(int), KM_SLEEP);
for (i = 0; i < ebh->peb_nr; i++) {
ebh->lmap[i] = EBH_LEB_UNMAPPED;
}
if (si->num_of_eb == 0) {
/* The flash contains no data. */
avg_ec = 0;
}
else {
avg_ec = (int) (si->sum_of_ec / si->num_of_eb);
}
dbg_ebh("num_of_eb: %d\n", si->num_of_eb);
mutex_enter(&ebh->erase_lock);
RB_FOREACH(sleb, scan_leb_used_rbtree, &si->used) {
ebh->lmap[sleb->lnr] = sleb->pebnr;
err = add_peb_to_in_use(ebh, sleb->pebnr, sleb->erase_cnt);
if (err)
goto out_free;
}
TAILQ_FOREACH(sleb, &si->erased, u.queue) {
err = add_peb_to_erase_queue(ebh, sleb->pebnr, avg_ec,
&ebh->fully_erased);
if (err)
goto out_free;
}
TAILQ_FOREACH(sleb, &si->erase, u.queue) {
err = add_peb_to_erase_queue(ebh, sleb->pebnr, avg_ec,
&ebh->to_erase);
if (err)
goto out_free;
}
TAILQ_FOREACH(sleb, &si->free, u.queue) {
err = add_peb_to_free(ebh, sleb->pebnr, sleb->erase_cnt);
if (err)
goto out_free;
}
TAILQ_FOREACH(sleb, &si->corrupted, u.queue) {
err = add_peb_to_erase_queue(ebh, sleb->pebnr, avg_ec,
&ebh->to_erase);
if (err)
goto out_free;
}
mutex_exit(&ebh->erase_lock);
scan_info_destroy(si);
return 0;
out_free:
mutex_exit(&ebh->erase_lock);
kmem_free(ebh->lmap, ebh->peb_nr * sizeof(int));
scan_info_destroy(si);
dbg_ebh("[SCAN_MEDIA] returning with error: %d\n", err);
return err;
}
/*****************************************************************************/
/* End of Scan related operations */
/*****************************************************************************/
/**
* ebh_open - opens mtd device and init ereaseblock header
* @ebh: eraseblock handler
* @flash_nr: flash device number to use
*
* Returns zero in case of success, error code in case of fail.
*/
int
ebh_open(struct chfs_ebh *ebh, dev_t dev)
{
int err;
ebh->flash_dev = flash_get_device(dev);
if (!ebh->flash_dev) {
aprint_error("ebh_open: cant get flash device\n");
return ENODEV;
}
ebh->flash_if = flash_get_interface(dev);
if (!ebh->flash_if) {
aprint_error("ebh_open: cant get flash interface\n");
return ENODEV;
}
ebh->flash_size = flash_get_size(dev);
ebh->peb_nr = ebh->flash_size / ebh->flash_if->erasesize;
// ebh->peb_nr = ebh->flash_if->size / ebh->flash_if->erasesize;
/* Set up flash operations based on flash type */
ebh->ops = kmem_alloc(sizeof(struct chfs_ebh_ops), KM_SLEEP);
switch (ebh->flash_if->type) {
case FLASH_TYPE_NOR:
ebh->eb_size = ebh->flash_if->erasesize -
CHFS_EB_EC_HDR_SIZE - CHFS_EB_HDR_NOR_SIZE;
ebh->ops->read_eb_hdr = nor_read_eb_hdr;
ebh->ops->write_eb_hdr = nor_write_eb_hdr;
ebh->ops->check_eb_hdr = nor_check_eb_hdr;
ebh->ops->mark_eb_hdr_dirty_flash =
nor_mark_eb_hdr_dirty_flash;
ebh->ops->invalidate_eb_hdr = nor_invalidate_eb_hdr;
ebh->ops->mark_eb_hdr_free = mark_eb_hdr_free;
ebh->ops->process_eb = nor_process_eb;
ebh->ops->create_eb_hdr = nor_create_eb_hdr;
ebh->ops->calc_data_offs = nor_calc_data_offs;
ebh->max_serial = NULL;
break;
case FLASH_TYPE_NAND:
ebh->eb_size = ebh->flash_if->erasesize -
2 * ebh->flash_if->page_size;
ebh->ops->read_eb_hdr = nand_read_eb_hdr;
ebh->ops->write_eb_hdr = nand_write_eb_hdr;
ebh->ops->check_eb_hdr = nand_check_eb_hdr;
ebh->ops->mark_eb_hdr_free = mark_eb_hdr_free;
ebh->ops->mark_eb_hdr_dirty_flash = NULL;
ebh->ops->invalidate_eb_hdr = NULL;
ebh->ops->process_eb = nand_process_eb;
ebh->ops->create_eb_hdr = nand_create_eb_hdr;
ebh->ops->calc_data_offs = nand_calc_data_offs;
ebh->max_serial = kmem_alloc(sizeof(uint64_t), KM_SLEEP);
*ebh->max_serial = 0;
break;
default:
return 1;
}
printf("opening ebh: eb_size: %zu\n", ebh->eb_size);
err = scan_media(ebh);
if (err) {
dbg_ebh("Scan failed.");
kmem_free(ebh->ops, sizeof(struct chfs_ebh_ops));
kmem_free(ebh, sizeof(struct chfs_ebh));
return err;
}
return 0;
}
/**
* ebh_close - close ebh
* @ebh: eraseblock handler
* Returns zero in case of success, error code in case of fail.
*/
int
ebh_close(struct chfs_ebh *ebh)
{
erase_thread_stop(ebh);
EBH_TREE_DESTROY(peb_free_rbtree, &ebh->free, struct chfs_peb);
EBH_TREE_DESTROY(peb_in_use_rbtree, &ebh->in_use, struct chfs_peb);
EBH_QUEUE_DESTROY(&ebh->fully_erased, struct chfs_peb, u.queue);
EBH_QUEUE_DESTROY(&ebh->to_erase, struct chfs_peb, u.queue);
/* XXX HACK, see ebh.h */
EBH_TREE_DESTROY_MUTEX(ltree_rbtree, &ebh->ltree,
struct chfs_ltree_entry);
KASSERT(!mutex_owned(&ebh->ltree_lock));
KASSERT(!mutex_owned(&ebh->alc_mutex));
KASSERT(!mutex_owned(&ebh->erase_lock));
mutex_destroy(&ebh->ltree_lock);
mutex_destroy(&ebh->alc_mutex);
mutex_destroy(&ebh->erase_lock);
kmem_free(ebh->ops, sizeof(struct chfs_ebh_ops));
kmem_free(ebh, sizeof(struct chfs_ebh));
return 0;
}
/**
* ebh_read_leb - read data from leb
* @ebh: eraseblock handler
* @lnr: logical eraseblock number
* @buf: buffer to read to
* @offset: offset from where to read
* @len: bytes number to read
*
* Returns zero in case of success, error code in case of fail.
*/
int
ebh_read_leb(struct chfs_ebh *ebh, int lnr, char *buf, uint32_t offset,
size_t len, size_t *retlen)
{
int err, pebnr;
off_t data_offset;
KASSERT(offset + len <= ebh->eb_size);
err = leb_read_lock(ebh, lnr);
if (err)
return err;
pebnr = ebh->lmap[lnr];
/* If PEB is not mapped the buffer is filled with 0xFF */
if (EBH_LEB_UNMAPPED == pebnr) {
leb_read_unlock(ebh, lnr);
memset(buf, 0xFF, len);
return 0;
}
/* Read data */
data_offset = ebh->ops->calc_data_offs(ebh, pebnr, offset);
err = flash_read(ebh->flash_dev, data_offset, len, retlen,
(unsigned char *) buf);
if (err)
goto out_free;
KASSERT(len == *retlen);
leb_read_unlock(ebh, lnr);
return err;
out_free:
leb_read_unlock(ebh, lnr);
return err;
}
/**
* get_peb: get a free physical eraseblock
* @ebh - chfs eraseblock handler
*
* This function gets a free eraseblock from the ebh->free RB-tree.
* The fist entry will be returned and deleted from the tree.
* The entries sorted by the erase counters, so the PEB with the smallest
* erase counter will be added back.
* If something goes bad a negative value will be returned.
*/
int
get_peb(struct chfs_ebh *ebh)
{
int err, pebnr;
struct chfs_peb *peb;
retry:
mutex_enter(&ebh->erase_lock);
//dbg_ebh("LOCK: ebh->erase_lock spin locked in get_peb()\n");
if (RB_EMPTY(&ebh->free)) {
/*There is no more free PEBs in the tree*/
if (TAILQ_EMPTY(&ebh->to_erase) &&
TAILQ_EMPTY(&ebh->fully_erased)) {
mutex_exit(&ebh->erase_lock);
//dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in get_peb()\n");
return ENOSPC;
}
err = free_peb(ebh);
mutex_exit(&ebh->erase_lock);
//dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in get_peb()\n");
if (err)
return err;
goto retry;
}
peb = RB_MIN(peb_free_rbtree, &ebh->free);
pebnr = peb->pebnr;
RB_REMOVE(peb_free_rbtree, &ebh->free, peb);
err = add_peb_to_in_use(ebh, peb->pebnr, peb->erase_cnt);
if (err)
pebnr = err;
kmem_free(peb, sizeof(struct chfs_peb));
mutex_exit(&ebh->erase_lock);
//dbg_ebh("UNLOCK: ebh->erase_lock spin unlocked in get_peb()\n");
return pebnr;
}
/**
* ebh_write_leb - write data to leb
* @ebh: eraseblock handler
* @lnr: logical eraseblock number
* @buf: data to write
* @offset: offset where to write
* @len: bytes number to write
*
* Returns zero in case of success, error code in case of fail.
*/
int
ebh_write_leb(struct chfs_ebh *ebh, int lnr, char *buf, uint32_t offset,
size_t len, size_t *retlen)
{
int err, pebnr, retries = 0;
off_t data_offset;
struct chfs_eb_hdr *ebhdr;
dbg("offset: %d | len: %zu | (offset+len): %zu "
" | ebsize: %zu\n", offset, len, (offset+len), ebh->eb_size);
KASSERT(offset + len <= ebh->eb_size);
err = leb_write_lock(ebh, lnr);
if (err)
return err;
pebnr = ebh->lmap[lnr];
/* If the LEB is mapped write out data */
if (pebnr != EBH_LEB_UNMAPPED) {
data_offset = ebh->ops->calc_data_offs(ebh, pebnr, offset);
err = flash_write(ebh->flash_dev, data_offset, len, retlen,
(unsigned char *) buf);
if (err) {
chfs_err("error %d while writing %zu bytes to PEB "
"%d:%ju, written %zu bytes\n",
err, len, pebnr, (uintmax_t )offset, *retlen);
} else {
KASSERT(len == *retlen);
}
leb_write_unlock(ebh, lnr);
return err;
}
/*
* If the LEB is unmapped, get a free PEB and write the
* eraseblock header first
*/
ebhdr = kmem_alloc(sizeof(struct chfs_eb_hdr), KM_SLEEP);
/* Setting up eraseblock header properties */
ebh->ops->create_eb_hdr(ebhdr, lnr);
retry:
/* Getting a physical eraseblock from the wear leveling system */
pebnr = get_peb(ebh);
if (pebnr < 0) {
leb_write_unlock(ebh, lnr);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return pebnr;
}
/* Write the eraseblock header to the media */
err = ebh->ops->write_eb_hdr(ebh, pebnr, ebhdr);
if (err) {
chfs_warn(
"error writing eraseblock header: LEB %d , PEB %d\n",
lnr, pebnr);
goto write_error;
}
/* Write out data */
if (len) {
data_offset = ebh->ops->calc_data_offs(ebh, pebnr, offset);
err = flash_write(ebh->flash_dev,
data_offset, len, retlen, (unsigned char *) buf);
if (err) {
chfs_err("error %d while writing %zu bytes to PEB "
" %d:%ju, written %zu bytes\n",
err, len, pebnr, (uintmax_t )offset, *retlen);
goto write_error;
}
}
ebh->lmap[lnr] = pebnr;
leb_write_unlock(ebh, lnr);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return 0;
write_error: err = release_peb(ebh, pebnr);
// max retries (NOW: 2)
if (err || CHFS_MAX_GET_PEB_RETRIES < ++retries) {
leb_write_unlock(ebh, lnr);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return err;
}
goto retry;
}
/**
* ebh_erase_leb - erase a leb
* @ebh: eraseblock handler
* @lnr: leb number
*
* Returns zero in case of success, error code in case of fail.
*/
int
ebh_erase_leb(struct chfs_ebh *ebh, int lnr)
{
int err, pebnr;
leb_write_lock(ebh, lnr);
pebnr = ebh->lmap[lnr];
if (pebnr < 0) {
leb_write_unlock(ebh, lnr);
return EBH_LEB_UNMAPPED;
}
err = release_peb(ebh, pebnr);
if (err)
goto out_unlock;
ebh->lmap[lnr] = EBH_LEB_UNMAPPED;
cv_signal(&ebh->bg_erase.eth_wakeup);
out_unlock:
leb_write_unlock(ebh, lnr);
return err;
}
/**
* ebh_map_leb - maps a PEB to LEB
* @ebh: eraseblock handler
* @lnr: leb number
*
* Returns zero on success, error code in case of fail
*/
int
ebh_map_leb(struct chfs_ebh *ebh, int lnr)
{
int err, pebnr, retries = 0;
struct chfs_eb_hdr *ebhdr;
ebhdr = kmem_alloc(sizeof(struct chfs_eb_hdr), KM_SLEEP);
err = leb_write_lock(ebh, lnr);
if (err)
return err;
retry:
pebnr = get_peb(ebh);
if (pebnr < 0) {
err = pebnr;
goto out_unlock;
}
ebh->ops->create_eb_hdr(ebhdr, lnr);
err = ebh->ops->write_eb_hdr(ebh, pebnr, ebhdr);
if (err) {
chfs_warn(
"error writing eraseblock header: LEB %d , PEB %d\n",
lnr, pebnr);
goto write_error;
}
ebh->lmap[lnr] = pebnr;
out_unlock:
leb_write_unlock(ebh, lnr);
return err;
write_error:
err = release_peb(ebh, pebnr);
// max retries (NOW: 2)
if (err || CHFS_MAX_GET_PEB_RETRIES < ++retries) {
leb_write_unlock(ebh, lnr);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return err;
}
goto retry;
}
/**
* ebh_unmap_leb -
* @ebh: eraseblock handler
* @lnr: leb number
*
* Retruns zero on success, error code in case of fail.
*/
int
ebh_unmap_leb(struct chfs_ebh *ebh, int lnr)
{
int err;
if (ebh_is_mapped(ebh, lnr) < 0)
/* If the eraseblock already unmapped */
return 0;
err = ebh_erase_leb(ebh, lnr);
return err;
}
/**
* ebh_is_mapped - check if a PEB is mapped to @lnr
* @ebh: eraseblock handler
* @lnr: leb number
*
* Retruns 0 if the logical eraseblock is mapped, negative error code otherwise.
*/
int
ebh_is_mapped(struct chfs_ebh *ebh, int lnr)
{
int err, result;
err = leb_read_lock(ebh, lnr);
if (err)
return err;
result = ebh->lmap[lnr];
leb_read_unlock(ebh, lnr);
return result;
}
/**
* ebh_change_leb - write the LEB to another PEB
* @ebh: eraseblock handler
* @lnr: leb number
* @buf: data to write
* @len: length of data
* Returns zero in case of success, error code in case of fail.
*/
int
ebh_change_leb(struct chfs_ebh *ebh, int lnr, char *buf, size_t len,
size_t *retlen)
{
int err, pebnr, pebnr_old, retries = 0;
off_t data_offset;
struct chfs_peb *peb = NULL;
struct chfs_eb_hdr *ebhdr;
if (ebh_is_mapped(ebh, lnr) < 0)
return EBH_LEB_UNMAPPED;
if (len == 0) {
err = ebh_unmap_leb(ebh, lnr);
if (err)
return err;
return ebh_map_leb(ebh, lnr);
}
ebhdr = kmem_alloc(sizeof(struct chfs_eb_hdr), KM_SLEEP);
pebnr_old = ebh->lmap[lnr];
mutex_enter(&ebh->alc_mutex);
err = leb_write_lock(ebh, lnr);
if (err)
goto out_mutex;
if (ebh->ops->mark_eb_hdr_dirty_flash) {
err = ebh->ops->mark_eb_hdr_dirty_flash(ebh, pebnr_old, lnr);
if (err)
goto out_unlock;
}
/* Setting up eraseblock header properties */
ebh->ops->create_eb_hdr(ebhdr, lnr);
retry:
/* Getting a physical eraseblock from the wear leveling system */
pebnr = get_peb(ebh);
if (pebnr < 0) {
leb_write_unlock(ebh, lnr);
mutex_exit(&ebh->alc_mutex);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return pebnr;
}
err = ebh->ops->write_eb_hdr(ebh, pebnr, ebhdr);
if (err) {
chfs_warn(
"error writing eraseblock header: LEB %d , PEB %d",
lnr, pebnr);
goto write_error;
}
/* Write out data */
data_offset = ebh->ops->calc_data_offs(ebh, pebnr, 0);
err = flash_write(ebh->flash_dev, data_offset, len, retlen,
(unsigned char *) buf);
if (err) {
chfs_err("error %d while writing %zu bytes to PEB %d:%ju,"
" written %zu bytes",
err, len, pebnr, (uintmax_t)data_offset, *retlen);
goto write_error;
}
ebh->lmap[lnr] = pebnr;
if (ebh->ops->invalidate_eb_hdr) {
err = ebh->ops->invalidate_eb_hdr(ebh, pebnr_old);
if (err)
goto out_unlock;
}
peb = find_peb_in_use(ebh, pebnr_old);
err = release_peb(ebh, peb->pebnr);
out_unlock:
leb_write_unlock(ebh, lnr);
out_mutex:
mutex_exit(&ebh->alc_mutex);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
kmem_free(peb, sizeof(struct chfs_peb));
return err;
write_error:
err = release_peb(ebh, pebnr);
//max retries (NOW: 2)
if (err || CHFS_MAX_GET_PEB_RETRIES < ++retries) {
leb_write_unlock(ebh, lnr);
mutex_exit(&ebh->alc_mutex);
kmem_free(ebhdr, sizeof(struct chfs_eb_hdr));
return err;
}
goto retry;
}