[PATCH 1/2] lightnvm: pblk: only try to recover lines with written smeta

From: Hans Holmberg
Date: Mon Apr 16 2018 - 12:47:16 EST


From: Hans Holmberg <hans.holmberg@xxxxxxxxxxxx>

When switching between different lun configurations, there is no
guarantee that all lines that contain closed/open chunks have some
valid data to recover.

Check that the smeta chunk has been written to instead. Also
skip bad lines (that does not have enough good chunks).

Signed-off-by: Hans Holmberg <hans.holmberg@xxxxxxxxxxxx>
---
drivers/lightnvm/pblk-recovery.c | 30 +++++++++++++++++++++---------
1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/drivers/lightnvm/pblk-recovery.c b/drivers/lightnvm/pblk-recovery.c
index 3e079c2..9cb6d5d 100644
--- a/drivers/lightnvm/pblk-recovery.c
+++ b/drivers/lightnvm/pblk-recovery.c
@@ -865,18 +865,30 @@ static void pblk_recov_wa_counters(struct pblk *pblk,
}

static int pblk_line_was_written(struct pblk_line *line,
- struct pblk_line_meta *lm)
+ struct pblk *pblk)
{

- int i;
- int state_mask = NVM_CHK_ST_OFFLINE | NVM_CHK_ST_FREE;
+ struct pblk_line_meta *lm = &pblk->lm;
+ struct nvm_tgt_dev *dev = pblk->dev;
+ struct nvm_geo *geo = &dev->geo;
+ struct nvm_chk_meta *chunk;
+ struct ppa_addr bppa;
+ int smeta_blk;

- for (i = 0; i < lm->blk_per_line; i++) {
- if (!(line->chks[i].state & state_mask))
- return 1;
- }
+ if (line->state == PBLK_LINESTATE_BAD)
+ return 0;

- return 0;
+ smeta_blk = find_first_zero_bit(line->blk_bitmap, lm->blk_per_line);
+ if (smeta_blk >= lm->blk_per_line)
+ return 0;
+
+ bppa = pblk->luns[smeta_blk].bppa;
+ chunk = &line->chks[pblk_ppa_to_pos(geo, bppa)];
+
+ if (chunk->state & NVM_CHK_ST_FREE)
+ return 0;
+
+ return 1;
}

struct pblk_line *pblk_recov_l2p(struct pblk *pblk)
@@ -915,7 +927,7 @@ struct pblk_line *pblk_recov_l2p(struct pblk *pblk)
line->lun_bitmap = ((void *)(smeta_buf)) +
sizeof(struct line_smeta);

- if (!pblk_line_was_written(line, lm))
+ if (!pblk_line_was_written(line, pblk))
continue;

/* Lines that cannot be read are assumed as not written here */
--
2.7.4