From: Darrick J. Wong <djwong@xxxxxxxxxx>
XFS now supports FITRIM to the realtime volume. Detect this support and
enable it.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
common/xfs | 40 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 38 insertions(+), 2 deletions(-)
diff --git a/common/xfs b/common/xfs
index 7ee6fbec84..de557ebd90 100644
--- a/common/xfs
+++ b/common/xfs
@@ -1777,8 +1777,44 @@ _require_xfs_scratch_atomicswap()
# of 1024 byte blocks.
_xfs_discard_max_offset_kb()
{
- $XFS_IO_PROG -c 'statfs' "$1" | \
- awk '{g[$1] = $3} END {print (g["geom.bsize"] * g["geom.datablocks"] / 1024)}'
+ local statfs
+
+ # Use awk to read the statfs output for the XFS filesystem, compute
+ # the two possible FITRIM offset maximums, and then use some horrid
+ # bash magic to import the five numbers as an indexed array. There's
+ # no better way to do this in bash since you can't readarray to build
+ # an associative array. Elements are as follows:
+ #
+ # 0: fsblock size in bytes
+ # 1: Data volume size in fsblocks.
+ # 2: Realtime volume size in fsblocks.
+ # 3: Max FITRIM offset if we can only trim the data volume
+ # 4: Max FITRIM offset if we can trim the data and rt volumes
+ readarray -t statfs < <($XFS_IO_PROG -c 'statfs' "$1" | \
+ awk '{g[$1] = $3} END {printf("%d\n%d\n%d\n%d\n%d\n",
+ g["geom.bsize"],
+ g["geom.datablocks"],
+ g["geom.rtblocks"],
+ g["geom.bsize"] * g["geom.datablocks"] / 1024,
+ g["geom.bsize"] * (g["geom.datablocks"] + g["geom.rtblocks"]) / 1024);}')
+
+ # If the kernel supports discarding the realtime volume, then it will
+ # not reject a FITRIM for fsblock dblks+1, even if the len/minlen
+ # arguments are absurd.
+ if [ "${statfs[2]}" -gt 0 ]; then
+ if $FSTRIM_PROG -o "$((statfs[0] * statfs[1]))" \
+ -l "${statfs[0]}" \
+ -m "$((statfs[0] * 2))" "$1" &>/dev/null; then
+ # The kernel supports discarding the rt volume, so
+ # print out the second answer from above.
+ echo "${statfs[4]}"
+ return
+ fi
+ fi
+
+ # The kernel does not support discarding the rt volume or there is no
+ # rt volume. Print out the first answer from above.
+ echo "${statfs[3]}"
}
# check if mkfs and the kernel support nocrc (v4) file systems
