kernel/drivers/md/persistent-data/dm-space-map-common.c, branch linux-5.1.y

dm: Avoid namespace collision with bitmap API

2018-08-01T22:49:38Z

bitmap API (include/linux/bitmap.h) has 'bitmap' prefix for its methods. On the other hand DM bitmap API is special case. Adding 'dm' prefix to it to avoid potential name space collision. No functional changes intended. Suggested-by: Mike Snitzer Signed-off-by: Andy Shevchenko Acked-by: Mike Snitzer Signed-off-by: Dmitry Torokhov

dm space map common: memcpy the disk root to ensure it's arch aligned

2017-02-16T18:02:54Z

The metadata_space_map_root passed to sm_ll_open_metadata() may or may not be arch aligned, use memcpy to ensure it is. This is not a fast path so the extra memcpy doesn't hurt us. Long-term it'd be better to use the kernel's alignment infrastructure to remove the memcpy()s that are littered across persistent-data (btree, array, space-maps, etc). Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm space map: always set ev if sm_ll_mutate() succeeds

2016-12-08T19:13:15Z

If no block was allocated or freed, sm_ll_mutate() wasn't setting *ev, leaving the variable unitialized. sm_ll_insert(), sm_disk_inc_block(), and sm_disk_new_block() all check ev to see if there was an allocation event in sm_ll_mutate(), possibly reading unitialized data. If no allocation event occured, sm_ll_mutate() should set *ev to SM_NONE. Signed-off-by: Benjamin Marzinski Acked-by: Joe Thornber Signed-off-by: Mike Snitzer

dm space map metadata: skip useless memcpy in metadata_ll_init_index()

2016-12-08T19:13:15Z

When metadata_ll_init_index() is called by sm_ll_new_metadata(), ll->mi_le hasn't been initialized yet. So, when metadata_ll_init_index() copies the contents of ll->mi_le into the newly allocated bitmap_root, it is just copying garbage. ll->mi_le will be allocated later in sm_ll_extend() and copied into the bitmap_root, in sm_ll_commit(). Signed-off-by: Benjamin Marzinski Signed-off-by: Mike Snitzer

dm persistent data: eliminate unnecessary return values

2015-10-31T23:06:02Z

dm_bm_unlock and dm_tm_unlock return an integer value but the returned value is always 0. The calling code sometimes checks the return value and sometimes doesn't. Eliminate these unnecessary return values and also the checks for them. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer

dm space map common: make sure new space is used during extend

2014-01-08T02:05:17Z

When extending a low level space map we should update nr_blocks at the start so the new space is used for the index entries. Otherwise extend can fail, e.g.: sm_metadata_extend call sequence that fails: -> sm_ll_extend -> dm_tm_new_block -> dm_sm_new_block -> sm_bootstrap_new_block => returns -ENOSPC because smm->begin == smm->ll.nr_blocks Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org

dm space map: disallow decrementing a reference count below zero

2013-12-13T19:22:09Z

The old behaviour, returning -EINVAL if a ref_count of 0 would be decremented, was removed in commit f722063 ("dm space map: optimise sm_ll_dec and sm_ll_inc"). To fix this regression we return an error code from the mutator function pointer passed to sm_ll_mutate() and have dec_ref_count() return -EINVAL if the old ref_count is 0. Add a DMERR to reflect the potential seriousness of this error. Also, add missing dm_tm_unlock() to sm_ll_mutate()'s error path. With this fix the following dmts regression test now passes: dmtest run --suite cache -n /metadata_use_kernel/ The next patch fixes the higher-level dm-array code that exposed this regression. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org # 3.12+

dm space map: optimise sm_ll_dec and sm_ll_inc

2013-08-23T13:02:14Z

Prior to this patch these methods did a lookup followed by an insert. Instead they now call a common mutate function that adjusts the value according to a callback function. This avoids traversing the data structures twice and hence improves performance. Also factor out sm_ll_lookup_big_ref_count() for use by both sm_ll_lookup() and sm_ll_mutate(). Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon

dm persistent data: use DMERR_LIMIT for errors

2012-12-21T20:23:34Z

Nearly all of persistent-data is in the IO path so throttle error messages with DMERR_LIMIT to limit the amount logged when something has gone wrong. Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon

dm persistent data: convert to use le32_add_cpu

2012-10-12T15:59:47Z

Convert cpu_to_le32(le32_to_cpu(E1) + E2) to use le32_add_cpu(). dpatch engine is used to auto generate this patch. (https://github.com/weiyj/dpatch) Signed-off-by: Wei Yongjun Signed-off-by: Alasdair G Kergon