Etienne Dechamps 30930fba21 Add support for DISCARD to ZVOLs. ... DISCARD (REQ_DISCARD, BLKDISCARD) is useful for thin provisioning. It allows ZVOL clients to discard (unmap, trim) block ranges from a ZVOL, thus optimizing disk space usage by allowing a ZVOL to shrink instead of just grow. We can't use zfs_space() or zfs_freesp() here, since these functions only work on regular files, not volumes. Fortunately we can use the low-level function dmu_free_long_range() which does exactly what we want. Currently the discard operation is not added to the log. That's not a big deal since losing discard requests cannot result in data corruption. It would however result in disk space usage higher than it should be. Thus adding log support to zvol_discard() is probably a good idea for a future improvement. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>		2012-02-09 16:19:38 -08:00
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libzfs_changelist.c	Remove HAVE_ZPL from commands and libraries	2011-02-04 16:14:34 -08:00
libzfs_config.c	Fix gcc missing braces warnings	2010-08-27 15:34:03 -07:00
libzfs_dataset.c	Ignore dataset if the dds_type is DMU_OST_OTHER	2012-01-19 09:29:48 -08:00
libzfs_diff.c	Add linux compatibility	2010-08-31 13:41:59 -07:00
libzfs_fru.c	Add linux topology support	2010-08-31 13:42:00 -07:00
libzfs_graph.c	Fix gcc missing braces warnings	2010-08-27 15:34:03 -07:00
libzfs_import.c	Improve 'zpool import' safety	2011-02-17 09:35:43 -08:00
libzfs_mount.c	Add overlay(-O) mount option support	2012-01-12 15:49:38 -08:00
libzfs_pool.c	Allow GPT+EFI vdev replacement in boot pools.	2012-01-18 11:05:24 -08:00
libzfs_sendrecv.c	Fix 'zfs send -D' segfault	2011-06-09 13:58:48 -07:00
libzfs_status.c	Use gethostid in the Linux convention.	2011-04-25 10:36:17 -05:00
libzfs_util.c	Use /dev/null for stdout/stderr in libzfs_run_process().	2011-08-01 13:52:23 -07:00
Makefile.am	Combine libraries: spl, avl, efi, share, unicode.	2012-01-17 15:19:50 -08:00
Makefile.in	Add support for DISCARD to ZVOLs.	2012-02-09 16:19:38 -08:00