lightnvm: pblk: add l2p crc debug printouts

Print the CRC of the logical-to-physical mapping during exit and
after recovering the L2P table to facilitate detection of meta
data corruption/recovery issues.

The CRC printed after recovery should match the CRC printed during
the previous exit - if it doesn't this indicates that either the meta
data written to the disk is corrupt or recovery failed.

Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Hans Holmberg 2017-10-13 14:46:40 +02:00 committed by Jens Axboe
parent 1edebacf8b
commit c55861926a

View file

@ -76,6 +76,28 @@ static blk_qc_t pblk_make_rq(struct request_queue *q, struct bio *bio)
return BLK_QC_T_NONE;
}
static size_t pblk_trans_map_size(struct pblk *pblk)
{
int entry_size = 8;
if (pblk->ppaf_bitsize < 32)
entry_size = 4;
return entry_size * pblk->rl.nr_secs;
}
#ifdef CONFIG_NVM_DEBUG
static u32 pblk_l2p_crc(struct pblk *pblk)
{
size_t map_size;
u32 crc = ~(u32)0;
map_size = pblk_trans_map_size(pblk);
crc = crc32_le(crc, pblk->trans_map, map_size);
return crc;
}
#endif
static void pblk_l2p_free(struct pblk *pblk)
{
vfree(pblk->trans_map);
@ -85,12 +107,10 @@ static int pblk_l2p_init(struct pblk *pblk)
{
sector_t i;
struct ppa_addr ppa;
int entry_size = 8;
size_t map_size;
if (pblk->ppaf_bitsize < 32)
entry_size = 4;
pblk->trans_map = vmalloc(entry_size * pblk->rl.nr_secs);
map_size = pblk_trans_map_size(pblk);
pblk->trans_map = vmalloc(map_size);
if (!pblk->trans_map)
return -ENOMEM;
@ -508,6 +528,10 @@ static int pblk_lines_configure(struct pblk *pblk, int flags)
}
}
#ifdef CONFIG_NVM_DEBUG
pr_info("pblk init: L2P CRC: %x\n", pblk_l2p_crc(pblk));
#endif
/* Free full lines directly as GC has not been started yet */
pblk_gc_free_full_lines(pblk);
@ -901,6 +925,11 @@ static void pblk_exit(void *private)
down_write(&pblk_lock);
pblk_gc_exit(pblk);
pblk_tear_down(pblk);
#ifdef CONFIG_NVM_DEBUG
pr_info("pblk exit: L2P CRC: %x\n", pblk_l2p_crc(pblk));
#endif
pblk_free(pblk);
up_write(&pblk_lock);
}