linux/drivers/lightnvm/pblk-write.c

666 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2016 CNEX Labs
* Initial release: Javier Gonzalez <javier@cnexlabs.com>
* Matias Bjorling <matias@cnexlabs.com>
*
* 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.
*
* pblk-write.c - pblk's write path from write buffer to media
*/
#include "pblk.h"
#include "pblk-trace.h"
static unsigned long pblk_end_w_bio(struct pblk *pblk, struct nvm_rq *rqd,
struct pblk_c_ctx *c_ctx)
{
struct bio *original_bio;
struct pblk_rb *rwb = &pblk->rwb;
unsigned long ret;
int i;
for (i = 0; i < c_ctx->nr_valid; i++) {
struct pblk_w_ctx *w_ctx;
int pos = c_ctx->sentry + i;
int flags;
w_ctx = pblk_rb_w_ctx(rwb, pos);
flags = READ_ONCE(w_ctx->flags);
if (flags & PBLK_FLUSH_ENTRY) {
flags &= ~PBLK_FLUSH_ENTRY;
/* Release flags on context. Protect from writes */
smp_store_release(&w_ctx->flags, flags);
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_dec(&rwb->inflight_flush_point);
#endif
}
while ((original_bio = bio_list_pop(&w_ctx->bios)))
bio_endio(original_bio);
}
if (c_ctx->nr_padded)
pblk_bio_free_pages(pblk, rqd->bio, c_ctx->nr_valid,
c_ctx->nr_padded);
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_long_add(rqd->nr_ppas, &pblk->sync_writes);
#endif
ret = pblk_rb_sync_advance(&pblk->rwb, c_ctx->nr_valid);
bio_put(rqd->bio);
pblk_free_rqd(pblk, rqd, PBLK_WRITE);
return ret;
}
static unsigned long pblk_end_queued_w_bio(struct pblk *pblk,
struct nvm_rq *rqd,
struct pblk_c_ctx *c_ctx)
{
list_del(&c_ctx->list);
return pblk_end_w_bio(pblk, rqd, c_ctx);
}
static void pblk_complete_write(struct pblk *pblk, struct nvm_rq *rqd,
struct pblk_c_ctx *c_ctx)
{
struct pblk_c_ctx *c, *r;
unsigned long flags;
unsigned long pos;
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_long_sub(c_ctx->nr_valid, &pblk->inflight_writes);
#endif
pblk_up_rq(pblk, c_ctx->lun_bitmap);
pos = pblk_rb_sync_init(&pblk->rwb, &flags);
if (pos == c_ctx->sentry) {
pos = pblk_end_w_bio(pblk, rqd, c_ctx);
retry:
list_for_each_entry_safe(c, r, &pblk->compl_list, list) {
rqd = nvm_rq_from_c_ctx(c);
if (c->sentry == pos) {
pos = pblk_end_queued_w_bio(pblk, rqd, c);
goto retry;
}
}
} else {
WARN_ON(nvm_rq_from_c_ctx(c_ctx) != rqd);
list_add_tail(&c_ctx->list, &pblk->compl_list);
}
pblk_rb_sync_end(&pblk->rwb, &flags);
}
/* Map remaining sectors in chunk, starting from ppa */
static void pblk_map_remaining(struct pblk *pblk, struct ppa_addr *ppa,
int rqd_ppas)
{
struct pblk_line *line;
struct ppa_addr map_ppa = *ppa;
__le64 addr_empty = cpu_to_le64(ADDR_EMPTY);
__le64 *lba_list;
u64 paddr;
int done = 0;
int n = 0;
line = pblk_ppa_to_line(pblk, *ppa);
lba_list = emeta_to_lbas(pblk, line->emeta->buf);
spin_lock(&line->lock);
while (!done) {
paddr = pblk_dev_ppa_to_line_addr(pblk, map_ppa);
if (!test_and_set_bit(paddr, line->map_bitmap))
line->left_msecs--;
if (n < rqd_ppas && lba_list[paddr] != addr_empty)
line->nr_valid_lbas--;
lba_list[paddr] = addr_empty;
if (!test_and_set_bit(paddr, line->invalid_bitmap))
le32_add_cpu(line->vsc, -1);
done = nvm_next_ppa_in_chk(pblk->dev, &map_ppa);
n++;
}
line->w_err_gc->has_write_err = 1;
spin_unlock(&line->lock);
}
static void pblk_prepare_resubmit(struct pblk *pblk, unsigned int sentry,
unsigned int nr_entries)
{
struct pblk_rb *rb = &pblk->rwb;
struct pblk_rb_entry *entry;
struct pblk_line *line;
struct pblk_w_ctx *w_ctx;
struct ppa_addr ppa_l2p;
int flags;
unsigned int i;
spin_lock(&pblk->trans_lock);
for (i = 0; i < nr_entries; i++) {
entry = &rb->entries[pblk_rb_ptr_wrap(rb, sentry, i)];
w_ctx = &entry->w_ctx;
/* Check if the lba has been overwritten */
if (w_ctx->lba != ADDR_EMPTY) {
ppa_l2p = pblk_trans_map_get(pblk, w_ctx->lba);
if (!pblk_ppa_comp(ppa_l2p, entry->cacheline))
w_ctx->lba = ADDR_EMPTY;
}
/* Mark up the entry as submittable again */
flags = READ_ONCE(w_ctx->flags);
flags |= PBLK_WRITTEN_DATA;
/* Release flags on write context. Protect from writes */
smp_store_release(&w_ctx->flags, flags);
/* Decrease the reference count to the line as we will
* re-map these entries
*/
line = pblk_ppa_to_line(pblk, w_ctx->ppa);
atomic_dec(&line->sec_to_update);
kref_put(&line->ref, pblk_line_put);
}
spin_unlock(&pblk->trans_lock);
}
static void pblk_queue_resubmit(struct pblk *pblk, struct pblk_c_ctx *c_ctx)
{
struct pblk_c_ctx *r_ctx;
r_ctx = kzalloc(sizeof(struct pblk_c_ctx), GFP_KERNEL);
if (!r_ctx)
return;
r_ctx->lun_bitmap = NULL;
r_ctx->sentry = c_ctx->sentry;
r_ctx->nr_valid = c_ctx->nr_valid;
r_ctx->nr_padded = c_ctx->nr_padded;
spin_lock(&pblk->resubmit_lock);
list_add_tail(&r_ctx->list, &pblk->resubmit_list);
spin_unlock(&pblk->resubmit_lock);
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_long_add(c_ctx->nr_valid, &pblk->recov_writes);
#endif
}
static void pblk_submit_rec(struct work_struct *work)
{
struct pblk_rec_ctx *recovery =
container_of(work, struct pblk_rec_ctx, ws_rec);
struct pblk *pblk = recovery->pblk;
struct nvm_rq *rqd = recovery->rqd;
struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
struct ppa_addr *ppa_list = nvm_rq_to_ppa_list(rqd);
pblk_log_write_err(pblk, rqd);
pblk_map_remaining(pblk, ppa_list, rqd->nr_ppas);
pblk_queue_resubmit(pblk, c_ctx);
pblk_up_rq(pblk, c_ctx->lun_bitmap);
if (c_ctx->nr_padded)
pblk_bio_free_pages(pblk, rqd->bio, c_ctx->nr_valid,
c_ctx->nr_padded);
bio_put(rqd->bio);
pblk_free_rqd(pblk, rqd, PBLK_WRITE);
mempool_free(recovery, &pblk->rec_pool);
atomic_dec(&pblk->inflight_io);
pblk_write_kick(pblk);
}
static void pblk_end_w_fail(struct pblk *pblk, struct nvm_rq *rqd)
{
struct pblk_rec_ctx *recovery;
recovery = mempool_alloc(&pblk->rec_pool, GFP_ATOMIC);
if (!recovery) {
pblk_err(pblk, "could not allocate recovery work\n");
return;
}
recovery->pblk = pblk;
recovery->rqd = rqd;
INIT_WORK(&recovery->ws_rec, pblk_submit_rec);
queue_work(pblk->close_wq, &recovery->ws_rec);
}
static void pblk_end_io_write(struct nvm_rq *rqd)
{
struct pblk *pblk = rqd->private;
struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
if (rqd->error) {
pblk_end_w_fail(pblk, rqd);
return;
} else {
if (trace_pblk_chunk_state_enabled())
pblk_check_chunk_state_update(pblk, rqd);
#ifdef CONFIG_NVM_PBLK_DEBUG
WARN_ONCE(rqd->bio->bi_status, "pblk: corrupted write error\n");
#endif
}
pblk_complete_write(pblk, rqd, c_ctx);
atomic_dec(&pblk->inflight_io);
}
static void pblk_end_io_write_meta(struct nvm_rq *rqd)
{
struct pblk *pblk = rqd->private;
struct pblk_g_ctx *m_ctx = nvm_rq_to_pdu(rqd);
struct pblk_line *line = m_ctx->private;
struct pblk_emeta *emeta = line->emeta;
struct ppa_addr *ppa_list = nvm_rq_to_ppa_list(rqd);
int sync;
pblk_up_chunk(pblk, ppa_list[0]);
if (rqd->error) {
pblk_log_write_err(pblk, rqd);
pblk_err(pblk, "metadata I/O failed. Line %d\n", line->id);
line->w_err_gc->has_write_err = 1;
} else {
if (trace_pblk_chunk_state_enabled())
pblk_check_chunk_state_update(pblk, rqd);
}
sync = atomic_add_return(rqd->nr_ppas, &emeta->sync);
if (sync == emeta->nr_entries)
pblk_gen_run_ws(pblk, line, NULL, pblk_line_close_ws,
GFP_ATOMIC, pblk->close_wq);
pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT);
atomic_dec(&pblk->inflight_io);
}
static int pblk_alloc_w_rq(struct pblk *pblk, struct nvm_rq *rqd,
unsigned int nr_secs, nvm_end_io_fn(*end_io))
{
/* Setup write request */
rqd->opcode = NVM_OP_PWRITE;
rqd->nr_ppas = nr_secs;
rqd->is_seq = 1;
rqd->private = pblk;
rqd->end_io = end_io;
return pblk_alloc_rqd_meta(pblk, rqd);
}
static int pblk_setup_w_rq(struct pblk *pblk, struct nvm_rq *rqd,
struct ppa_addr *erase_ppa)
{
struct pblk_line_meta *lm = &pblk->lm;
struct pblk_line *e_line = pblk_line_get_erase(pblk);
struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
unsigned int valid = c_ctx->nr_valid;
unsigned int padded = c_ctx->nr_padded;
unsigned int nr_secs = valid + padded;
unsigned long *lun_bitmap;
int ret;
lun_bitmap = kzalloc(lm->lun_bitmap_len, GFP_KERNEL);
if (!lun_bitmap)
return -ENOMEM;
c_ctx->lun_bitmap = lun_bitmap;
ret = pblk_alloc_w_rq(pblk, rqd, nr_secs, pblk_end_io_write);
if (ret) {
kfree(lun_bitmap);
return ret;
}
if (likely(!e_line || !atomic_read(&e_line->left_eblks)))
ret = pblk_map_rq(pblk, rqd, c_ctx->sentry, lun_bitmap,
valid, 0);
else
ret = pblk_map_erase_rq(pblk, rqd, c_ctx->sentry, lun_bitmap,
valid, erase_ppa);
return ret;
}
static int pblk_calc_secs_to_sync(struct pblk *pblk, unsigned int secs_avail,
unsigned int secs_to_flush)
{
int secs_to_sync;
secs_to_sync = pblk_calc_secs(pblk, secs_avail, secs_to_flush, true);
#ifdef CONFIG_NVM_PBLK_DEBUG
if ((!secs_to_sync && secs_to_flush)
|| (secs_to_sync < 0)
|| (secs_to_sync > secs_avail && !secs_to_flush)) {
pblk_err(pblk, "bad sector calculation (a:%d,s:%d,f:%d)\n",
secs_avail, secs_to_sync, secs_to_flush);
}
#endif
return secs_to_sync;
}
int pblk_submit_meta_io(struct pblk *pblk, struct pblk_line *meta_line)
{
struct nvm_tgt_dev *dev = pblk->dev;
struct nvm_geo *geo = &dev->geo;
struct pblk_line_mgmt *l_mg = &pblk->l_mg;
struct pblk_line_meta *lm = &pblk->lm;
struct pblk_emeta *emeta = meta_line->emeta;
struct ppa_addr *ppa_list;
struct pblk_g_ctx *m_ctx;
struct nvm_rq *rqd;
void *data;
u64 paddr;
int rq_ppas = pblk->min_write_pgs;
int id = meta_line->id;
int rq_len;
int i, j;
int ret;
rqd = pblk_alloc_rqd(pblk, PBLK_WRITE_INT);
m_ctx = nvm_rq_to_pdu(rqd);
m_ctx->private = meta_line;
rq_len = rq_ppas * geo->csecs;
data = ((void *)emeta->buf) + emeta->mem;
ret = pblk_alloc_w_rq(pblk, rqd, rq_ppas, pblk_end_io_write_meta);
if (ret)
goto fail_free_rqd;
ppa_list = nvm_rq_to_ppa_list(rqd);
for (i = 0; i < rqd->nr_ppas; ) {
spin_lock(&meta_line->lock);
paddr = __pblk_alloc_page(pblk, meta_line, rq_ppas);
spin_unlock(&meta_line->lock);
for (j = 0; j < rq_ppas; j++, i++, paddr++)
ppa_list[i] = addr_to_gen_ppa(pblk, paddr, id);
}
spin_lock(&l_mg->close_lock);
emeta->mem += rq_len;
if (emeta->mem >= lm->emeta_len[0])
list_del(&meta_line->list);
spin_unlock(&l_mg->close_lock);
pblk_down_chunk(pblk, ppa_list[0]);
ret = pblk_submit_io(pblk, rqd, data);
if (ret) {
pblk_err(pblk, "emeta I/O submission failed: %d\n", ret);
goto fail_rollback;
}
return NVM_IO_OK;
fail_rollback:
pblk_up_chunk(pblk, ppa_list[0]);
spin_lock(&l_mg->close_lock);
pblk_dealloc_page(pblk, meta_line, rq_ppas);
list_add(&meta_line->list, &meta_line->list);
spin_unlock(&l_mg->close_lock);
fail_free_rqd:
pblk_free_rqd(pblk, rqd, PBLK_WRITE_INT);
return ret;
}
static inline bool pblk_valid_meta_ppa(struct pblk *pblk,
struct pblk_line *meta_line,
struct nvm_rq *data_rqd)
{
struct nvm_tgt_dev *dev = pblk->dev;
struct nvm_geo *geo = &dev->geo;
struct pblk_c_ctx *data_c_ctx = nvm_rq_to_pdu(data_rqd);
struct pblk_line *data_line = pblk_line_get_data(pblk);
struct ppa_addr ppa, ppa_opt;
u64 paddr;
int pos_opt;
/* Schedule a metadata I/O that is half the distance from the data I/O
* with regards to the number of LUNs forming the pblk instance. This
* balances LUN conflicts across every I/O.
*
* When the LUN configuration changes (e.g., due to GC), this distance
* can align, which would result on metadata and data I/Os colliding. In
* this case, modify the distance to not be optimal, but move the
* optimal in the right direction.
*/
paddr = pblk_lookup_page(pblk, meta_line);
ppa = addr_to_gen_ppa(pblk, paddr, 0);
ppa_opt = addr_to_gen_ppa(pblk, paddr + data_line->meta_distance, 0);
pos_opt = pblk_ppa_to_pos(geo, ppa_opt);
if (test_bit(pos_opt, data_c_ctx->lun_bitmap) ||
test_bit(pos_opt, data_line->blk_bitmap))
return true;
if (unlikely(pblk_ppa_comp(ppa_opt, ppa)))
data_line->meta_distance--;
return false;
}
static struct pblk_line *pblk_should_submit_meta_io(struct pblk *pblk,
struct nvm_rq *data_rqd)
{
struct pblk_line_meta *lm = &pblk->lm;
struct pblk_line_mgmt *l_mg = &pblk->l_mg;
struct pblk_line *meta_line;
spin_lock(&l_mg->close_lock);
if (list_empty(&l_mg->emeta_list)) {
spin_unlock(&l_mg->close_lock);
return NULL;
}
meta_line = list_first_entry(&l_mg->emeta_list, struct pblk_line, list);
if (meta_line->emeta->mem >= lm->emeta_len[0]) {
spin_unlock(&l_mg->close_lock);
return NULL;
}
spin_unlock(&l_mg->close_lock);
if (!pblk_valid_meta_ppa(pblk, meta_line, data_rqd))
return NULL;
return meta_line;
}
static int pblk_submit_io_set(struct pblk *pblk, struct nvm_rq *rqd)
{
struct ppa_addr erase_ppa;
struct pblk_line *meta_line;
int err;
pblk_ppa_set_empty(&erase_ppa);
/* Assign lbas to ppas and populate request structure */
err = pblk_setup_w_rq(pblk, rqd, &erase_ppa);
if (err) {
pblk_err(pblk, "could not setup write request: %d\n", err);
return NVM_IO_ERR;
}
meta_line = pblk_should_submit_meta_io(pblk, rqd);
/* Submit data write for current data line */
err = pblk_submit_io(pblk, rqd, NULL);
if (err) {
pblk_err(pblk, "data I/O submission failed: %d\n", err);
return NVM_IO_ERR;
}
if (!pblk_ppa_empty(erase_ppa)) {
/* Submit erase for next data line */
if (pblk_blk_erase_async(pblk, erase_ppa)) {
struct pblk_line *e_line = pblk_line_get_erase(pblk);
struct nvm_tgt_dev *dev = pblk->dev;
struct nvm_geo *geo = &dev->geo;
int bit;
atomic_inc(&e_line->left_eblks);
bit = pblk_ppa_to_pos(geo, erase_ppa);
WARN_ON(!test_and_clear_bit(bit, e_line->erase_bitmap));
}
}
if (meta_line) {
/* Submit metadata write for previous data line */
err = pblk_submit_meta_io(pblk, meta_line);
if (err) {
pblk_err(pblk, "metadata I/O submission failed: %d",
err);
return NVM_IO_ERR;
}
}
return NVM_IO_OK;
}
static void pblk_free_write_rqd(struct pblk *pblk, struct nvm_rq *rqd)
{
struct pblk_c_ctx *c_ctx = nvm_rq_to_pdu(rqd);
struct bio *bio = rqd->bio;
if (c_ctx->nr_padded)
pblk_bio_free_pages(pblk, bio, c_ctx->nr_valid,
c_ctx->nr_padded);
}
static int pblk_submit_write(struct pblk *pblk, int *secs_left)
{
struct bio *bio;
struct nvm_rq *rqd;
unsigned int secs_avail, secs_to_sync, secs_to_com;
unsigned int secs_to_flush, packed_meta_pgs;
unsigned long pos;
unsigned int resubmit;
*secs_left = 0;
spin_lock(&pblk->resubmit_lock);
resubmit = !list_empty(&pblk->resubmit_list);
spin_unlock(&pblk->resubmit_lock);
/* Resubmit failed writes first */
if (resubmit) {
struct pblk_c_ctx *r_ctx;
spin_lock(&pblk->resubmit_lock);
r_ctx = list_first_entry(&pblk->resubmit_list,
struct pblk_c_ctx, list);
list_del(&r_ctx->list);
spin_unlock(&pblk->resubmit_lock);
secs_avail = r_ctx->nr_valid;
pos = r_ctx->sentry;
pblk_prepare_resubmit(pblk, pos, secs_avail);
secs_to_sync = pblk_calc_secs_to_sync(pblk, secs_avail,
secs_avail);
kfree(r_ctx);
} else {
/* If there are no sectors in the cache,
* flushes (bios without data) will be cleared on
* the cache threads
*/
secs_avail = pblk_rb_read_count(&pblk->rwb);
if (!secs_avail)
return 0;
secs_to_flush = pblk_rb_flush_point_count(&pblk->rwb);
if (!secs_to_flush && secs_avail < pblk->min_write_pgs_data)
return 0;
secs_to_sync = pblk_calc_secs_to_sync(pblk, secs_avail,
secs_to_flush);
if (secs_to_sync > pblk->max_write_pgs) {
pblk_err(pblk, "bad buffer sync calculation\n");
return 0;
}
secs_to_com = (secs_to_sync > secs_avail) ?
secs_avail : secs_to_sync;
pos = pblk_rb_read_commit(&pblk->rwb, secs_to_com);
}
packed_meta_pgs = (pblk->min_write_pgs - pblk->min_write_pgs_data);
bio = bio_alloc(GFP_KERNEL, secs_to_sync + packed_meta_pgs);
bio->bi_iter.bi_sector = 0; /* internal bio */
bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
rqd = pblk_alloc_rqd(pblk, PBLK_WRITE);
rqd->bio = bio;
if (pblk_rb_read_to_bio(&pblk->rwb, rqd, pos, secs_to_sync,
secs_avail)) {
pblk_err(pblk, "corrupted write bio\n");
goto fail_put_bio;
}
if (pblk_submit_io_set(pblk, rqd))
goto fail_free_bio;
#ifdef CONFIG_NVM_PBLK_DEBUG
atomic_long_add(secs_to_sync, &pblk->sub_writes);
#endif
*secs_left = 1;
return 0;
fail_free_bio:
pblk_free_write_rqd(pblk, rqd);
fail_put_bio:
bio_put(bio);
pblk_free_rqd(pblk, rqd, PBLK_WRITE);
return -EINTR;
}
int pblk_write_ts(void *data)
{
struct pblk *pblk = data;
int secs_left;
int write_failure = 0;
while (!kthread_should_stop()) {
if (!write_failure) {
write_failure = pblk_submit_write(pblk, &secs_left);
if (secs_left)
continue;
}
set_current_state(TASK_INTERRUPTIBLE);
io_schedule();
}
return 0;
}