- 根目录:
- drivers
- lightnvm
- gennvm.c
/*
* Copyright (C) 2015 Matias Bjorling <m@bjorling.me>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* 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; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
* USA.
*
* Implementation of a generic nvm manager for Open-Channel SSDs.
*/
#include "gennvm.h"
static void gennvm_blocks_free(struct nvm_dev *dev)
{
struct gen_nvm *gn = dev->mp;
struct gen_lun *lun;
int i;
gennvm_for_each_lun(gn, lun, i) {
if (!lun->vlun.blocks)
break;
vfree(lun->vlun.blocks);
}
}
static void gennvm_luns_free(struct nvm_dev *dev)
{
struct gen_nvm *gn = dev->mp;
kfree(gn->luns);
}
static int gennvm_luns_init(struct nvm_dev *dev, struct gen_nvm *gn)
{
struct gen_lun *lun;
int i;
gn->luns = kcalloc(dev->nr_luns, sizeof(struct gen_lun), GFP_KERNEL);
if (!gn->luns)
return -ENOMEM;
gennvm_for_each_lun(gn, lun, i) {
spin_lock_init(&lun->vlun.lock);
INIT_LIST_HEAD(&lun->free_list);
INIT_LIST_HEAD(&lun->used_list);
INIT_LIST_HEAD(&lun->bb_list);
lun->reserved_blocks = 2; /* for GC only */
lun->vlun.id = i;
lun->vlun.lun_id = i % dev->luns_per_chnl;
lun->vlun.chnl_id = i / dev->luns_per_chnl;
lun->vlun.nr_free_blocks = dev->blks_per_lun;
lun->vlun.nr_inuse_blocks = 0;
lun->vlun.nr_bad_blocks = 0;
}
return 0;
}
static int gennvm_block_bb(struct ppa_addr ppa, int nr_blocks, u8 *blks,
void *private)
{
struct gen_nvm *gn = private;
struct nvm_dev *dev = gn->dev;
struct gen_lun *lun;
struct nvm_block *blk;
int i;
lun = &gn->luns[(dev->luns_per_chnl * ppa.g.ch) + ppa.g.lun];
for (i = 0; i < nr_blocks; i++) {
if (blks[i] == 0)
continue;
blk = &lun->vlun.blocks[i];
if (!blk) {
pr_err("gennvm: BB data is out of bounds.\n");
return -EINVAL;
}
list_move_tail(&blk->list, &lun->bb_list);
lun->vlun.nr_bad_blocks++;
}
return 0;
}
static int gennvm_block_map(u64 slba, u32 nlb, __le64 *entries, void *private)
{
struct nvm_dev *dev = private;
struct gen_nvm *gn = dev->mp;
sector_t max_pages = dev->total_pages * (dev->sec_size >> 9);
u64 elba = slba + nlb;
struct gen_lun *lun;
struct nvm_block *blk;
u64 i;
int lun_id;
if (unlikely(elba > dev->total_pages)) {
pr_err("gennvm: L2P data from device is out of bounds!\n");
return -EINVAL;
}
for (i = 0; i < nlb; i++) {
u64 pba = le64_to_cpu(entries[i]);
if (unlikely(pba >= max_pages && pba != U64_MAX)) {
pr_err("gennvm: L2P data entry is out of bounds!\n");
return -EINVAL;
}
/* Address zero is a special one. The first page on a disk is
* protected. It often holds internal device boot
* information.
*/
if (!pba)
continue;
/* resolve block from physical address */
lun_id = div_u64(pba, dev->sec_per_lun);
lun = &gn->luns[lun_id];
/* Calculate block offset into lun */
pba = pba - (dev->sec_per_lun * lun_id);
blk = &lun->vlun.blocks[div_u64(pba, dev->sec_per_blk)];
if (!blk->type) {
/* at this point, we don't know anything about the
* block. It's up to the FTL on top to re-etablish the
* block state
*/
list_move_tail(&blk->list, &lun->used_list);
blk->type = 1;
lun->vlun.nr_free_blocks--;
lun->vlun.nr_inuse_blocks++;
}
}
return 0;
}
static int gennvm_blocks_init(struct nvm_dev *dev, struct gen_nvm *gn)
{
struct gen_lun *lun;
struct nvm_block *block;
sector_t lun_iter, blk_iter, cur_block_id = 0;
int ret;
gennvm_for_each_lun(gn, lun, lun_iter) {
lun->vlun.blocks = vzalloc(sizeof(struct nvm_block) *
dev->blks_per_lun);
if (!lun->vlun.blocks)
return -ENOMEM;
for (blk_iter = 0; blk_iter < dev->blks_per_lun; blk_iter++) {
block = &lun->vlun.blocks[blk_iter];
INIT_LIST_HEAD(&block->list);
block->lun = &lun->vlun;
block->id = cur_block_id++;
/* First block is reserved for device */
if (unlikely(lun_iter == 0 && blk_iter == 0)) {
lun->vlun.nr_free_blocks--;
continue;
}
list_add_tail(&block->list, &lun->free_list);
}
if (dev->ops->get_bb_tbl) {
struct ppa_addr ppa;
ppa.ppa = 0;
ppa.g.ch = lun->vlun.chnl_id;
ppa.g.lun = lun->vlun.id;
ppa = generic_to_dev_addr(dev, ppa);
ret = dev->ops->get_bb_tbl(dev, ppa,
dev->blks_per_lun,
gennvm_block_bb, gn);
if (ret)
pr_err("gennvm: could not read BB table\n");
}
}
if (dev->ops->get_l2p_tbl) {
ret = dev->ops->get_l2p_tbl(dev, 0, dev->total_pages,
gennvm_block_map, dev);
if (ret) {
pr_err("gennvm: could not read L2P table.\n");
pr_warn("gennvm: default block initialization");
}
}
return 0;
}
static void gennvm_free(struct nvm_dev *dev)
{
gennvm_blocks_free(dev);
gennvm_luns_free(dev);
kfree(dev->mp);
dev->mp = NULL;
}
static int gennvm_register(struct nvm_dev *dev)
{
struct gen_nvm *gn;
int ret;
if (!try_module_get(THIS_MODULE))
return -ENODEV;
gn = kzalloc(sizeof(struct gen_nvm), GFP_KERNEL);
if (!gn)
return -ENOMEM;
gn->dev = dev;
gn->nr_luns = dev->nr_luns;
dev->mp = gn;
ret = gennvm_luns_init(dev, gn);
if (ret) {
pr_err("gennvm: could not initialize luns\n");
goto err;
}
ret = gennvm_blocks_init(dev, gn);
if (ret) {
pr_err("gennvm: could not initialize blocks\n");
goto err;
}
return 1;
err:
gennvm_free(dev);
module_put(THIS_MODULE);
return ret;
}
static void gennvm_unregister(struct nvm_dev *dev)
{
gennvm_free(dev);
module_put(THIS_MODULE);
}
static struct nvm_block *gennvm_get_blk(struct nvm_dev *dev,
struct nvm_lun *vlun, unsigned long flags)
{
struct gen_lun *lun = container_of(vlun, struct gen_lun, vlun);
struct nvm_block *blk = NULL;
int is_gc = flags & NVM_IOTYPE_GC;
spin_lock(&vlun->lock);
if (list_empty(&lun->free_list)) {
pr_err_ratelimited("gennvm: lun %u have no free pages available",
lun->vlun.id);
goto out;
}
if (!is_gc && lun->vlun.nr_free_blocks < lun->reserved_blocks)
goto out;
blk = list_first_entry(&lun->free_list, struct nvm_block, list);
list_move_tail(&blk->list, &lun->used_list);
blk->type = 1;
lun->vlun.nr_free_blocks--;
lun->vlun.nr_inuse_blocks++;
out:
spin_unlock(&vlun->lock);
return blk;
}
static void gennvm_put_blk(struct nvm_dev *dev, struct nvm_block *blk)
{
struct nvm_lun *vlun = blk->lun;
struct gen_lun *lun = container_of(vlun, struct gen_lun, vlun);
spin_lock(&vlun->lock);
switch (blk->type) {
case 1:
list_move_tail(&blk->list, &lun->free_list);
lun->vlun.nr_free_blocks++;
lun->vlun.nr_inuse_blocks--;
blk->type = 0;
break;
case 2:
list_move_tail(&blk->list, &lun->bb_list);
lun->vlun.nr_bad_blocks++;
lun->vlun.nr_inuse_blocks--;
break;
default:
WARN_ON_ONCE(1);
pr_err("gennvm: erroneous block type (%lu -> %u)\n",
blk->id, blk->type);
list_move_tail(&blk->list, &lun->bb_list);
lun->vlun.nr_bad_blocks++;
lun->vlun.nr_inuse_blocks--;
}
spin_unlock(&vlun->lock);
}
static void gennvm_addr_to_generic_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
{
int i;
if (rqd->nr_pages > 1) {
for (i = 0; i < rqd->nr_pages; i++)
rqd->ppa_list[i] = dev_to_generic_addr(dev,
rqd->ppa_list[i]);
} else {
rqd->ppa_addr = dev_to_generic_addr(dev, rqd->ppa_addr);
}
}
static void gennvm_generic_to_addr_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
{
int i;
if (rqd->nr_pages > 1) {
for (i = 0; i < rqd->nr_pages; i++)
rqd->ppa_list[i] = generic_to_dev_addr(dev,
rqd->ppa_list[i]);
} else {
rqd->ppa_addr = generic_to_dev_addr(dev, rqd->ppa_addr);
}
}
static int gennvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
{
if (!dev->ops->submit_io)
return 0;
/* Convert address space */
gennvm_generic_to_addr_mode(dev, rqd);
rqd->dev = dev;
return dev->ops->submit_io(dev, rqd);
}
static void gennvm_blk_set_type(struct nvm_dev *dev, struct ppa_addr *ppa,
int type)
{
struct gen_nvm *gn = dev->mp;
struct gen_lun *lun;
struct nvm_block *blk;
if (unlikely(ppa->g.ch > dev->nr_chnls ||
ppa->g.lun > dev->luns_per_chnl ||
ppa->g.blk > dev->blks_per_lun)) {
WARN_ON_ONCE(1);
pr_err("gennvm: ppa broken (ch: %u > %u lun: %u > %u blk: %u > %u",
ppa->g.ch, dev->nr_chnls,
ppa->g.lun, dev->luns_per_chnl,
ppa->g.blk, dev->blks_per_lun);
return;
}
lun = &gn->luns[ppa->g.lun * ppa->g.ch];
blk = &lun->vlun.blocks[ppa->g.blk];
/* will be moved to bb list on put_blk from target */
blk->type = type;
}
/* mark block bad. It is expected the target recover from the error. */
static void gennvm_mark_blk_bad(struct nvm_dev *dev, struct nvm_rq *rqd)
{
int i;
if (!dev->ops->set_bb_tbl)
return;
if (dev->ops->set_bb_tbl(dev, rqd, 1))
return;
gennvm_addr_to_generic_mode(dev, rqd);
/* look up blocks and mark them as bad */
if (rqd->nr_pages > 1)
for (i = 0; i < rqd->nr_pages; i++)
gennvm_blk_set_type(dev, &rqd->ppa_list[i], 2);
else
gennvm_blk_set_type(dev, &rqd->ppa_addr, 2);
}
static int gennvm_end_io(struct nvm_rq *rqd, int error)
{
struct nvm_tgt_instance *ins = rqd->ins;
int ret = 0;
switch (error) {
case NVM_RSP_SUCCESS:
break;
case NVM_RSP_ERR_EMPTYPAGE:
break;
case NVM_RSP_ERR_FAILWRITE:
gennvm_mark_blk_bad(rqd->dev, rqd);
default:
ret++;
}
ret += ins->tt->end_io(rqd, error);
return ret;
}
static int gennvm_erase_blk(struct nvm_dev *dev, struct nvm_block *blk,
unsigned long flags)
{
int plane_cnt = 0, pl_idx, ret;
struct ppa_addr addr;
struct nvm_rq rqd;
if (!dev->ops->erase_block)
return 0;
addr = block_to_ppa(dev, blk);
if (dev->plane_mode == NVM_PLANE_SINGLE) {
rqd.nr_pages = 1;
rqd.ppa_addr = addr;
} else {
plane_cnt = (1 << dev->plane_mode);
rqd.nr_pages = plane_cnt;
rqd.ppa_list = nvm_dev_dma_alloc(dev, GFP_KERNEL,
&rqd.dma_ppa_list);
if (!rqd.ppa_list) {
pr_err("gennvm: failed to allocate dma memory\n");
return -ENOMEM;
}
for (pl_idx = 0; pl_idx < plane_cnt; pl_idx++) {
addr.g.pl = pl_idx;
rqd.ppa_list[pl_idx] = addr;
}
}
gennvm_generic_to_addr_mode(dev, &rqd);
ret = dev->ops->erase_block(dev, &rqd);
if (plane_cnt)
nvm_dev_dma_free(dev, rqd.ppa_list, rqd.dma_ppa_list);
return ret;
}
static struct nvm_lun *gennvm_get_lun(struct nvm_dev *dev, int lunid)
{
struct gen_nvm *gn = dev->mp;
return &gn->luns[lunid].vlun;
}
static void gennvm_lun_info_print(struct nvm_dev *dev)
{
struct gen_nvm *gn = dev->mp;
struct gen_lun *lun;
unsigned int i;
gennvm_for_each_lun(gn, lun, i) {
spin_lock(&lun->vlun.lock);
pr_info("%s: lun%8u\t%u\t%u\t%u\n",
dev->name, i,
lun->vlun.nr_free_blocks,
lun->vlun.nr_inuse_blocks,
lun->vlun.nr_bad_blocks);
spin_unlock(&lun->vlun.lock);
}
}
static struct nvmm_type gennvm = {
.name = "gennvm",
.version = {0, 1, 0},
.register_mgr = gennvm_register,
.unregister_mgr = gennvm_unregister,
.get_blk = gennvm_get_blk,
.put_blk = gennvm_put_blk,
.submit_io = gennvm_submit_io,
.end_io = gennvm_end_io,
.erase_blk = gennvm_erase_blk,
.get_lun = gennvm_get_lun,
.lun_info_print = gennvm_lun_info_print,
};
static int __init gennvm_module_init(void)
{
return nvm_register_mgr(&gennvm);
}
static void gennvm_module_exit(void)
{
nvm_unregister_mgr(&gennvm);
}
module_init(gennvm_module_init);
module_exit(gennvm_module_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Generic media manager for Open-Channel SSDs");