lightnvm: pblk: refactor bad block identification

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 González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 109 insertions, 100 deletions

diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
index 49c65f1dd48b..141036bd6afa 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)
-{
-        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)
+static int pblk_bb_get_tbl(struct nvm_tgt_dev *dev, struct pblk_lun *rlun,
+                           u8 *blks, int nr_blks)
 {
-        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;
@@ -423,58 +417,63 @@ 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 int pblk_bb_line(struct pblk *pblk, struct pblk_line *line,
-                        int blk_per_line)
+static void *pblk_bb_get_log(struct pblk *pblk)
 {
         struct nvm_tgt_dev *dev = pblk->dev;
         struct nvm_geo *geo = &dev->geo;
-        struct pblk_lun *rlun;
-        int bb_cnt = 0;
-        int i;
+        u8 *log;
+        int i, nr_blks, blk_per_lun;
+        int ret;
 
-        for (i = 0; i < blk_per_line; i++) {
-                rlun = &pblk->luns[i];
-                if (rlun->bb_list[line->id] == NVM_BLK_T_FREE)
-                        continue;
+        blk_per_lun = geo->nr_chks * geo->plane_mode;
+        nr_blks = blk_per_lun * geo->all_luns;
 
-                set_bit(pblk_ppa_to_pos(geo, rlun->bppa), line->blk_bitmap);
-                bb_cnt++;
+        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 bb_cnt;
+        return log;
 }
 
-static int pblk_alloc_line_bitmaps(struct pblk *pblk, struct pblk_line *line)
+static int pblk_bb_line(struct pblk *pblk, struct pblk_line *line,
+                        u8 *bb_log, int blk_per_line)
 {
-        struct pblk_line_meta *lm = &pblk->lm;
+        struct nvm_tgt_dev *dev = pblk->dev;
+        struct nvm_geo *geo = &dev->geo;
+        int i, bb_cnt = 0;
 
-        line->blk_bitmap = kzalloc(lm->blk_bitmap_len, GFP_KERNEL);
-        if (!line->blk_bitmap)
-                return -ENOMEM;
+        for (i = 0; i < blk_per_line; i++) {
+                struct pblk_lun *rlun = &pblk->luns[i];
+                u8 *lun_bb_log = bb_log + i * blk_per_line;
 
-        line->erase_bitmap = kzalloc(lm->blk_bitmap_len, GFP_KERNEL);
-        if (!line->erase_bitmap) {
-                kfree(line->blk_bitmap);
-                return -ENOMEM;
+                if (lun_bb_log[line->id] == NVM_BLK_T_FREE)
+                        continue;
+
+                set_bit(pblk_ppa_to_pos(geo, rlun->bppa), line->blk_bitmap);
+                bb_cnt++;
         }
 
-        return 0;
+        return bb_cnt;
 }
 
 static int pblk_luns_init(struct pblk *pblk, struct ppa_addr *luns)
@@ -482,7 +481,7 @@ 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 @@ fail_free_smeta:
         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 @@ add_emeta_page:
         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 @@ add_emeta_page:
                 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_bb_aux;
+        }
+
         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 @@ add_emeta_page:
                 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 +875,19 @@ add_emeta_page:
 
         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_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 +931,7 @@ 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 +1119,7 @@ fail_free_core:
 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: