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author | Matias Bjørling <m@bjorling.me> | 2015-10-28 19:54:56 +0100 |
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committer | Jens Axboe <axboe@fb.com> | 2015-10-29 16:21:42 +0900 |
commit | 48add0f5a6f46919dd307575aad6ea3de7c9cb2a (patch) | |
tree | 1d30a56f86d8b74ffe5b80e977ededabea0ed080 /drivers/lightnvm/gennvm.c | |
parent | cd9e9808d18fe7107c306f6e71c8be7230ee42b4 (diff) | |
download | linux-48add0f5a6f46919dd307575aad6ea3de7c9cb2a.tar.gz linux-48add0f5a6f46919dd307575aad6ea3de7c9cb2a.tar.bz2 linux-48add0f5a6f46919dd307575aad6ea3de7c9cb2a.zip |
gennvm: Generic NVM manager
The implementation for Open-Channel SSDs is divided into media
management and targets. This patch implements a generic media manager
for open-channel SSDs. After a media manager has been initialized,
single or multiple targets can be instantiated with the media managed as
the backend.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'drivers/lightnvm/gennvm.c')
-rw-r--r-- | drivers/lightnvm/gennvm.c | 485 |
1 files changed, 485 insertions, 0 deletions
diff --git a/drivers/lightnvm/gennvm.c b/drivers/lightnvm/gennvm.c new file mode 100644 index 000000000000..ae1fb2bdc5f4 --- /dev/null +++ b/drivers/lightnvm/gennvm.c @@ -0,0 +1,485 @@ +/* + * 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; + } + return 0; +} + +static int gennvm_block_bb(u32 lun_id, void *bb_bitmap, unsigned int nr_blocks, + void *private) +{ + struct gen_nvm *gn = private; + struct gen_lun *lun = &gn->luns[lun_id]; + struct nvm_block *blk; + int i; + + if (unlikely(bitmap_empty(bb_bitmap, nr_blocks))) + return 0; + + i = -1; + while ((i = find_next_bit(bb_bitmap, nr_blocks, i + 1)) < nr_blocks) { + 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); + } + + 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--; + } + } + + 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)) + continue; + + list_add_tail(&block->list, &lun->free_list); + } + + if (dev->ops->get_bb_tbl) { + ret = dev->ops->get_bb_tbl(dev->q, lun->vlun.id, + 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->q, 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 int gennvm_register(struct nvm_dev *dev) +{ + struct gen_nvm *gn; + int ret; + + gn = kzalloc(sizeof(struct gen_nvm), GFP_KERNEL); + if (!gn) + return -ENOMEM; + + 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: + kfree(gn); + return ret; +} + +static void gennvm_unregister(struct nvm_dev *dev) +{ + gennvm_blocks_free(dev); + gennvm_luns_free(dev); + kfree(dev->mp); + dev->mp = NULL; +} + +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); + spin_unlock(&vlun->lock); + goto out; + } + + while (!is_gc && lun->vlun.nr_free_blocks < lun->reserved_blocks) { + spin_unlock(&vlun->lock); + 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--; + + spin_unlock(&vlun->lock); +out: + 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++; + blk->type = 0; + break; + case 2: + list_move_tail(&blk->list, &lun->bb_list); + 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); + } + + 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] = addr_to_generic_mode(dev, + rqd->ppa_list[i]); + } else { + rqd->ppa_addr = addr_to_generic_mode(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_addr_mode(dev, + rqd->ppa_list[i]); + } else { + rqd->ppa_addr = generic_to_addr_mode(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->q, 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) + return; + + if (dev->ops->set_bb(dev->q, 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->q, &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_free_blocks_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) + pr_info("%s: lun%8u\t%u\n", + dev->name, i, lun->vlun.nr_free_blocks); +} + +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, + .free_blocks_print = gennvm_free_blocks_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"); |