4 Commits

Author	SHA1	Message	Date
Bryn M. Reeves	e0d19feb85	libdm: add dm_stats_update_regions_from_fd() ... Add a call to update the regions corresponding to a file mapped group of regions. The regions to be updated must be grouped, to allow us to correctly identify extents that have been deallocated since the map was created. Tables are built of the file extents, and the extents currently mapped to dmstats regions: if a region no longer has a matching file extent, it is deleted, and new regions are created for any file extents without a matching region. The FIEMAP call returns extents that are currently in-memory (or journaled) and awaiting allocation in the file system. These have the FIEMAP_EXTENT_UNKNOWN | FIEMAP_EXTENT_DELALLOC flag bits set in the fe_flags field - these extents are skipped until they have a known disk location. Since it is possile for the 0th extent of the file to have been deallocated this must also handle the possible deletion and re-creation of the group leader: if no other region allocation is taking place the group identifier will not change.	2017-01-25 16:15:21 +00:00
Bryn M. Reeves	c90e9392e4	libdm: add dm_stats_bind_from_fd() ... dmsetup already has a version of this function, and dmfilemapd will need it too: move it to libdevmapper to avoid copying it around.	2016-12-18 20:47:17 +00:00
Bryn M. Reeves	7dff632c11	libdm: add min_num_bits to dm_bitset_parse_list() ... It's useful to be able to specify a minimum number of bits for a new bitmap parsed from a list, for e.g. to allow for expansing a group without needing to copy/reallocate the bitmap. Add a backwards compatible symbol for programs linked against old versions of the library.	2016-12-13 21:02:18 +00:00
Bryn M. Reeves	5d1d65e735	libdm: add dm_bit_get_last()/dm_bit_get_prev() ... It is sometimes convenient to iterate over the set bits in a dm bitset in reverse order (from the highest set bit toward zero), or to quickly find the last set bit. Add dm_bit_get_last() and dm_bit_get_prev(), mirroring the existing dm_bit_get_first() and dm_bit_get_next(). dm_bit_get_prev() uses __builtin_clz when available to efficiently test the bitset in reverse.	2016-12-13 21:01:58 +00:00