[PATCH 5/5] lightnvm: pblk: refactor bad block identification

From: Javier GonzÃlez
Date: Tue Jan 30 2018 - 21:07:43 EST


In preparation for the OCSSD 2.0 spec. bad block identification,
refactor the current code to generalize bad block get/set functions and
structures.

Signed-off-by: Javier GonzÃlez <javier@xxxxxxxxxxxx>
---
drivers/lightnvm/pblk-init.c | 213 +++++++++++++++++++++++--------------------
drivers/lightnvm/pblk.h | 6 --
2 files changed, 112 insertions(+), 107 deletions(-)

diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
index a5e3510c0f38..86a94a7faa96 100644
--- a/drivers/lightnvm/pblk-init.c
+++ b/drivers/lightnvm/pblk-init.c
@@ -365,7 +365,25 @@ static void pblk_luns_free(struct pblk *pblk)
kfree(pblk->luns);
}

-static void pblk_free_line_bitmaps(struct pblk_line *line)
+static void pblk_line_mg_free(struct pblk *pblk)
+{
+ struct pblk_line_mgmt *l_mg = &pblk->l_mg;
+ int i;
+
+ kfree(l_mg->bb_template);
+ kfree(l_mg->bb_aux);
+ kfree(l_mg->vsc_list);
+
+ for (i = 0; i < PBLK_DATA_LINES; i++) {
+ kfree(l_mg->sline_meta[i]);
+ pblk_mfree(l_mg->eline_meta[i]->buf, l_mg->emeta_alloc_type);
+ kfree(l_mg->eline_meta[i]);
+ }
+
+ kfree(pblk->lines);
+}
+
+static void pblk_line_meta_free(struct pblk_line *line)
{
kfree(line->blk_bitmap);
kfree(line->erase_bitmap);
@@ -382,40 +400,16 @@ static void pblk_lines_free(struct pblk *pblk)
line = &pblk->lines[i];

pblk_line_free(pblk, line);
- pblk_free_line_bitmaps(line);
+ pblk_line_meta_free(line);
}
spin_unlock(&l_mg->free_lock);
}

-static void pblk_line_meta_free(struct pblk *pblk)
+static int pblk_bb_get_tbl(struct nvm_tgt_dev *dev, struct pblk_lun *rlun,
+ u8 *blks, int nr_blks)
{
- struct pblk_line_mgmt *l_mg = &pblk->l_mg;
- int i;
-
- kfree(l_mg->bb_template);
- kfree(l_mg->bb_aux);
- kfree(l_mg->vsc_list);
-
- for (i = 0; i < PBLK_DATA_LINES; i++) {
- kfree(l_mg->sline_meta[i]);
- pblk_mfree(l_mg->eline_meta[i]->buf, l_mg->emeta_alloc_type);
- kfree(l_mg->eline_meta[i]);
- }
-
- kfree(pblk->lines);
-}
-
-static int pblk_bb_discovery(struct nvm_tgt_dev *dev, struct pblk_lun *rlun)
-{
- struct nvm_geo *geo = &dev->geo;
struct ppa_addr ppa;
- u8 *blks;
- int nr_blks, ret;
-
- nr_blks = geo->nr_chks * geo->plane_mode;
- blks = kmalloc(nr_blks, GFP_KERNEL);
- if (!blks)
- return -ENOMEM;
+ int ret;

ppa.ppa = 0;
ppa.g.ch = rlun->bppa.g.ch;
@@ -423,34 +417,56 @@ static int pblk_bb_discovery(struct nvm_tgt_dev *dev, struct pblk_lun *rlun)

ret = nvm_get_tgt_bb_tbl(dev, ppa, blks);
if (ret)
- goto out;
+ return ret;

nr_blks = nvm_bb_tbl_fold(dev->parent, blks, nr_blks);
- if (nr_blks < 0) {
- ret = nr_blks;
- goto out;
- }
-
- rlun->bb_list = blks;
+ if (nr_blks < 0)
+ return -EIO;

return 0;
-out:
- kfree(blks);
- return ret;
+}
+
+static void *pblk_bb_get_log(struct pblk *pblk)
+{
+ struct nvm_tgt_dev *dev = pblk->dev;
+ struct nvm_geo *geo = &dev->geo;
+ u8 *log;
+ int i, nr_blks, blk_per_lun;
+ int ret;
+
+ blk_per_lun = geo->nr_chks * geo->plane_mode;
+ nr_blks = blk_per_lun * geo->all_luns;
+
+ log = kmalloc(nr_blks, GFP_KERNEL);
+ if (!log)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < geo->all_luns; i++) {
+ struct pblk_lun *rlun = &pblk->luns[i];
+ u8 *log_pos = log + i * blk_per_lun;
+
+ ret = pblk_bb_get_tbl(dev, rlun, log_pos, blk_per_lun);
+ if (ret) {
+ kfree(log);
+ return ERR_PTR(-EIO);
+ }
+ }
+
+ return log;
}

static int pblk_bb_line(struct pblk *pblk, struct pblk_line *line,
- int blk_per_line)
+ u8 *bb_log, int blk_per_line)
{
struct nvm_tgt_dev *dev = pblk->dev;
struct nvm_geo *geo = &dev->geo;
- struct pblk_lun *rlun;
- int bb_cnt = 0;
- int i;
+ int i, bb_cnt = 0;

for (i = 0; i < blk_per_line; i++) {
- rlun = &pblk->luns[i];
- if (rlun->bb_list[line->id] == NVM_BLK_T_FREE)
+ struct pblk_lun *rlun = &pblk->luns[i];
+ u8 *lun_bb_log = bb_log + i * blk_per_line;
+
+ if (lun_bb_log[line->id] == NVM_BLK_T_FREE)
continue;

set_bit(pblk_ppa_to_pos(geo, rlun->bppa), line->blk_bitmap);
@@ -460,29 +476,12 @@ static int pblk_bb_line(struct pblk *pblk, struct pblk_line *line,
return bb_cnt;
}

-static int pblk_alloc_line_bitmaps(struct pblk *pblk, struct pblk_line *line)
-{
- struct pblk_line_meta *lm = &pblk->lm;
-
- line->blk_bitmap = kzalloc(lm->blk_bitmap_len, GFP_KERNEL);
- if (!line->blk_bitmap)
- return -ENOMEM;
-
- line->erase_bitmap = kzalloc(lm->blk_bitmap_len, GFP_KERNEL);
- if (!line->erase_bitmap) {
- kfree(line->blk_bitmap);
- return -ENOMEM;
- }
-
- return 0;
-}
-
static int pblk_luns_init(struct pblk *pblk, struct ppa_addr *luns)
{
struct nvm_tgt_dev *dev = pblk->dev;
struct nvm_geo *geo = &dev->geo;
struct pblk_lun *rlun;
- int i, ret;
+ int i;

/* TODO: Implement unbalanced LUN support */
if (geo->nr_luns < 0) {
@@ -505,13 +504,6 @@ static int pblk_luns_init(struct pblk *pblk, struct ppa_addr *luns)
rlun->bppa = luns[lunid];

sema_init(&rlun->wr_sem, 1);
-
- ret = pblk_bb_discovery(dev, rlun);
- if (ret) {
- while (--i >= 0)
- kfree(pblk->luns[i].bb_list);
- return ret;
- }
}

return 0;
@@ -689,6 +681,26 @@ static int pblk_lines_alloc_metadata(struct pblk *pblk)
return -ENOMEM;
}

+static int pblk_setup_line_meta(struct pblk *pblk, struct pblk_line *line,
+ void *chunk_log, long *nr_bad_blks)
+{
+ struct pblk_line_meta *lm = &pblk->lm;
+
+ line->blk_bitmap = kzalloc(lm->blk_bitmap_len, GFP_KERNEL);
+ if (!line->blk_bitmap)
+ return -ENOMEM;
+
+ line->erase_bitmap = kzalloc(lm->blk_bitmap_len, GFP_KERNEL);
+ if (!line->erase_bitmap) {
+ kfree(line->blk_bitmap);
+ return -ENOMEM;
+ }
+
+ *nr_bad_blks = pblk_bb_line(pblk, line, chunk_log, lm->blk_per_line);
+
+ return 0;
+}
+
static int pblk_lines_init(struct pblk *pblk)
{
struct nvm_tgt_dev *dev = pblk->dev;
@@ -696,8 +708,9 @@ static int pblk_lines_init(struct pblk *pblk)
struct pblk_line_mgmt *l_mg = &pblk->l_mg;
struct pblk_line_meta *lm = &pblk->lm;
struct pblk_line *line;
+ void *chunk_log;
unsigned int smeta_len, emeta_len;
- long nr_bad_blks, nr_free_blks;
+ long nr_bad_blks = 0, nr_free_blks = 0;
int bb_distance, max_write_ppas, mod;
int i, ret;

@@ -771,13 +784,12 @@ static int pblk_lines_init(struct pblk *pblk)
if (lm->min_blk_line > lm->blk_per_line) {
pr_err("pblk: config. not supported. Min. LUN in line:%d\n",
lm->blk_per_line);
- ret = -EINVAL;
- goto fail;
+ return -EINVAL;
}

ret = pblk_lines_alloc_metadata(pblk);
if (ret)
- goto fail;
+ return ret;

l_mg->bb_template = kzalloc(lm->sec_bitmap_len, GFP_KERNEL);
if (!l_mg->bb_template) {
@@ -821,9 +833,16 @@ static int pblk_lines_init(struct pblk *pblk)
goto fail_free_bb_aux;
}

- nr_free_blks = 0;
+ chunk_log = pblk_bb_get_log(pblk);
+ if (IS_ERR(chunk_log)) {
+ pr_err("pblk: could not get bad block log (%lu)\n",
+ PTR_ERR(chunk_log));
+ ret = PTR_ERR(chunk_log);
+ goto fail_free_lines;
+ }
+
for (i = 0; i < l_mg->nr_lines; i++) {
- int blk_in_line;
+ int chk_in_line;

line = &pblk->lines[i];

@@ -835,26 +854,20 @@ static int pblk_lines_init(struct pblk *pblk)
line->vsc = &l_mg->vsc_list[i];
spin_lock_init(&line->lock);

- ret = pblk_alloc_line_bitmaps(pblk, line);
+ ret = pblk_setup_line_meta(pblk, line, chunk_log, &nr_bad_blks);
if (ret)
- goto fail_free_lines;
+ goto fail_free_chunk_log;

- nr_bad_blks = pblk_bb_line(pblk, line, lm->blk_per_line);
- if (nr_bad_blks < 0 || nr_bad_blks > lm->blk_per_line) {
- pblk_free_line_bitmaps(line);
- ret = -EINVAL;
- goto fail_free_lines;
- }
-
- blk_in_line = lm->blk_per_line - nr_bad_blks;
- if (blk_in_line < lm->min_blk_line) {
+ chk_in_line = lm->blk_per_line - nr_bad_blks;
+ if (nr_bad_blks < 0 || nr_bad_blks > lm->blk_per_line ||
+ chk_in_line < lm->min_blk_line) {
line->state = PBLK_LINESTATE_BAD;
list_add_tail(&line->list, &l_mg->bad_list);
continue;
}

- nr_free_blks += blk_in_line;
- atomic_set(&line->blk_in_line, blk_in_line);
+ nr_free_blks += chk_in_line;
+ atomic_set(&line->blk_in_line, chk_in_line);

l_mg->nr_free_lines++;
list_add_tail(&line->list, &l_mg->free_list);
@@ -862,23 +875,21 @@ static int pblk_lines_init(struct pblk *pblk)

pblk_set_provision(pblk, nr_free_blks);

- /* Cleanup per-LUN bad block lists - managed within lines on run-time */
- for (i = 0; i < geo->all_luns; i++)
- kfree(pblk->luns[i].bb_list);
-
+ kfree(chunk_log);
return 0;
-fail_free_lines:
+
+fail_free_chunk_log:
+ kfree(chunk_log);
while (--i >= 0)
- pblk_free_line_bitmaps(&pblk->lines[i]);
+ pblk_line_meta_free(&pblk->lines[i]);
+fail_free_lines:
+ kfree(pblk->lines);
fail_free_bb_aux:
kfree(l_mg->bb_aux);
fail_free_bb_template:
kfree(l_mg->bb_template);
fail_free_meta:
- pblk_line_meta_free(pblk);
-fail:
- for (i = 0; i < geo->all_luns; i++)
- kfree(pblk->luns[i].bb_list);
+ pblk_line_mg_free(pblk);

return ret;
}
@@ -922,7 +933,7 @@ static void pblk_free(struct pblk *pblk)
pblk_luns_free(pblk);
pblk_lines_free(pblk);
kfree(pblk->pad_dist);
- pblk_line_meta_free(pblk);
+ pblk_line_mg_free(pblk);
pblk_core_free(pblk);
pblk_l2p_free(pblk);

@@ -1110,7 +1121,7 @@ static void *pblk_init(struct nvm_tgt_dev *dev, struct gendisk *tdisk,
fail_free_pad_dist:
kfree(pblk->pad_dist);
fail_free_line_meta:
- pblk_line_meta_free(pblk);
+ pblk_line_mg_free(pblk);
fail_free_luns:
pblk_luns_free(pblk);
fail:
diff --git a/drivers/lightnvm/pblk.h b/drivers/lightnvm/pblk.h
index 88720e2441c0..282dfc8780e8 100644
--- a/drivers/lightnvm/pblk.h
+++ b/drivers/lightnvm/pblk.h
@@ -201,12 +201,6 @@ struct pblk_rb {

struct pblk_lun {
struct ppa_addr bppa;
-
- u8 *bb_list; /* Bad block list for LUN. Only used on
- * bring up. Bad blocks are managed
- * within lines on run-time.
- */
-
struct semaphore wr_sem;
};

--
2.7.4