Add a limited write failure mode, which will allow a write to a block to fail a specified amount of times, prior to remapping.
Add an interface for limited write failures, to be added by the following message: (Example: add bad block on block 60, with 5 write failures) dmsetup message 0 dust1 addbadblock 60 5 The write failure counter will be printed for newly added bad blocks. Signed-off-by: Bryan Gurney <[email protected]> --- drivers/md/dm-dust.c | 48 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 42 insertions(+), 6 deletions(-) diff --git a/drivers/md/dm-dust.c b/drivers/md/dm-dust.c index 8288887b7f94..3aecc0cb0fbd 100644 --- a/drivers/md/dm-dust.c +++ b/drivers/md/dm-dust.c @@ -17,6 +17,7 @@ struct badblock { struct rb_node node; sector_t bb; + unsigned char wr_fail_cnt; }; struct dust_device { @@ -101,7 +102,9 @@ static int dust_remove_block(struct dust_device *dd, unsigned long long block) return 0; } -static int dust_add_block(struct dust_device *dd, unsigned long long block) +static int dust_add_block(struct dust_device *dd, + unsigned long long block, + unsigned char wr_fail_cnt) { struct badblock *bblock; unsigned long flags; @@ -115,6 +118,7 @@ static int dust_add_block(struct dust_device *dd, unsigned long long block) spin_lock_irqsave(&dd->dust_lock, flags); bblock->bb = block; + bblock->wr_fail_cnt = wr_fail_cnt; if (!dust_rb_insert(&dd->badblocklist, bblock)) { if (!dd->quiet_mode) { DMERR("%s: block %llu already in badblocklist", @@ -127,7 +131,7 @@ static int dust_add_block(struct dust_device *dd, unsigned long long block) dd->badblock_count++; if (!dd->quiet_mode) - DMINFO("%s: badblock added at block %llu", __func__, block); + DMINFO("%s: badblock added at block %llu with write fail count %hhu", __func__, block, wr_fail_cnt); spin_unlock_irqrestore(&dd->dust_lock, flags); return 0; @@ -175,10 +179,15 @@ static int dust_map_read(struct dust_device *dd, sector_t thisblock, return ret; } -static void __dust_map_write(struct dust_device *dd, sector_t thisblock) +static int __dust_map_write(struct dust_device *dd, sector_t thisblock) { struct badblock *bblk = dust_rb_search(&dd->badblocklist, thisblock); + if (bblk && bblk->wr_fail_cnt > 0) { + bblk->wr_fail_cnt--; + return DM_MAPIO_KILL; + } + if (bblk) { rb_erase(&bblk->node, &dd->badblocklist); dd->badblock_count--; @@ -189,21 +198,24 @@ static void __dust_map_write(struct dust_device *dd, sector_t thisblock) (unsigned long long)thisblock); } } + + return DM_MAPIO_REMAPPED; } static int dust_map_write(struct dust_device *dd, sector_t thisblock, bool fail_read_on_bb) { unsigned long flags; + int ret = DM_MAPIO_REMAPPED; if (fail_read_on_bb) { thisblock >>= dd->sect_per_block_shift; spin_lock_irqsave(&dd->dust_lock, flags); - __dust_map_write(dd, thisblock); + ret = __dust_map_write(dd, thisblock); spin_unlock_irqrestore(&dd->dust_lock, flags); } - return DM_MAPIO_REMAPPED; + return ret; } static int dust_map(struct dm_target *ti, struct bio *bio) @@ -377,6 +389,8 @@ static int dust_message(struct dm_target *ti, unsigned int argc, char **argv, bool invalid_msg = false; int result = -EINVAL; unsigned long long tmp, block; + unsigned char wr_fail_cnt; + unsigned int tmp_ui; unsigned long flags; char dummy; @@ -422,14 +436,36 @@ static int dust_message(struct dm_target *ti, unsigned int argc, char **argv, } if (!strcasecmp(argv[0], "addbadblock")) - result = dust_add_block(dd, block); + result = dust_add_block(dd, block, 0); else if (!strcasecmp(argv[0], "removebadblock")) result = dust_remove_block(dd, block); else if (!strcasecmp(argv[0], "queryblock")) result = dust_query_block(dd, block); else invalid_msg = true; + } else if (argc == 3) { + if (sscanf(argv[1], "%llu%c", &tmp, &dummy) != 1) + return result; + + if (sscanf(argv[2], "%u%c", &tmp_ui, &dummy) != 1) + return result; + block = tmp; + if (tmp_ui > 255) { + DMERR("selected write fail count out of range"); + return result; + } + wr_fail_cnt = tmp_ui; + sector_div(size, dd->sect_per_block); + if (block > size) { + DMERR("selected block value out of range"); + return result; + } + + if (!strcasecmp(argv[0], "addbadblock")) + result = dust_add_block(dd, block, wr_fail_cnt); + else + invalid_msg = true; } else DMERR("invalid number of arguments '%d'", argc); -- 2.21.0 -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
