Enabling nrext64 option on mkfs.xfs command line extends the maximum values of
inode data and attr fork extent counters to 2^48 - 1 and 2^32 - 1
respectively. This also sets the XFS_SB_FEAT_INCOMPAT_NREXT64 incompat flag
on the superblock preventing older kernels from mounting such a filesystem.
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Signed-off-by: Chandan Babu R <chandan.babu@xxxxxxxxxx>
---
man/man8/mkfs.xfs.8.in | 7 +++++++
mkfs/lts_4.19.conf | 1 +
mkfs/lts_5.10.conf | 1 +
mkfs/lts_5.15.conf | 1 +
mkfs/lts_5.4.conf | 1 +
mkfs/xfs_mkfs.c | 23 +++++++++++++++++++++++
6 files changed, 34 insertions(+)
diff --git a/man/man8/mkfs.xfs.8.in b/man/man8/mkfs.xfs.8.in
index 7b7e4f48..1d8c55f0 100644
--- a/man/man8/mkfs.xfs.8.in
+++ b/man/man8/mkfs.xfs.8.in
@@ -640,6 +640,13 @@ space over time such that no free extents are large enough to
accommodate a chunk of 64 inodes. Without this feature enabled, inode
allocations can fail with out of space errors under severe fragmented
free space conditions.
+.TP
+.BI nrext64[= value]
+Extend maximum values of inode data and attr fork extent counters from 2^31 -
+1 and 2^15 - 1 to 2^48 - 1 and 2^32 - 1 respectively. If the value is
+omitted, 1 is assumed. This feature is disabled by default. This feature is
+only available for filesystems formatted with -m crc=1.
+.TP
.RE
.PP
.PD 0
diff --git a/mkfs/lts_4.19.conf b/mkfs/lts_4.19.conf
index d21fcb7e..751be45e 100644
--- a/mkfs/lts_4.19.conf
+++ b/mkfs/lts_4.19.conf
@@ -2,6 +2,7 @@
# kernel was released at the end of 2018.
[metadata]
+nrext64=0
bigtime=0
crc=1
finobt=1
diff --git a/mkfs/lts_5.10.conf b/mkfs/lts_5.10.conf
index ac00960e..a1c991ce 100644
--- a/mkfs/lts_5.10.conf
+++ b/mkfs/lts_5.10.conf
@@ -2,6 +2,7 @@
# kernel was released at the end of 2020.
[metadata]
+nrext64=0
bigtime=0
crc=1
finobt=1
diff --git a/mkfs/lts_5.15.conf b/mkfs/lts_5.15.conf
index 32082958..d751f4c4 100644
--- a/mkfs/lts_5.15.conf
+++ b/mkfs/lts_5.15.conf
@@ -2,6 +2,7 @@
# kernel was released at the end of 2021.
[metadata]
+nrext64=0
bigtime=1
crc=1
finobt=1
diff --git a/mkfs/lts_5.4.conf b/mkfs/lts_5.4.conf
index dd60b9f1..7e8a0ff0 100644
--- a/mkfs/lts_5.4.conf
+++ b/mkfs/lts_5.4.conf
@@ -2,6 +2,7 @@
# kernel was released at the end of 2019.
[metadata]
+nrext64=0
bigtime=0
crc=1
finobt=1
diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 8c9ef6fd..52f25e53 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -87,6 +87,7 @@ enum {
I_ATTR,
I_PROJID32BIT,
I_SPINODES,
+ I_NREXT64,
I_MAX_OPTS,
};
@@ -441,6 +442,7 @@ static struct opt_params iopts = {
[I_ATTR] = "attr",
[I_PROJID32BIT] = "projid32bit",
[I_SPINODES] = "sparse",
+ [I_NREXT64] = "nrext64",
},
.subopt_params = {
{ .index = I_ALIGN,
@@ -489,6 +491,12 @@ static struct opt_params iopts = {
.maxval = 1,
.defaultval = 1,
},
+ { .index = I_NREXT64,
+ .conflicts = { { NULL, LAST_CONFLICT } },
+ .minval = 0,
+ .maxval = 1,
+ .defaultval = 1,
+ }
},
};
@@ -813,6 +821,7 @@ struct sb_feat_args {
bool bigtime; /* XFS_SB_FEAT_INCOMPAT_BIGTIME */
bool nodalign;
bool nortalign;
+ bool nrext64;
};
struct cli_params {
@@ -1603,6 +1612,9 @@ inode_opts_parser(
case I_SPINODES:
cli->sb_feat.spinodes = getnum(value, opts, subopt);
break;
+ case I_NREXT64:
+ cli->sb_feat.nrext64 = getnum(value, opts, subopt);
+ break;
default:
return -EINVAL;
}
@@ -2180,6 +2192,14 @@ _("timestamps later than 2038 not supported without CRC support\n"));
usage();
}
cli->sb_feat.bigtime = false;
+
+ if (cli->sb_feat.nrext64 &&
+ cli_opt_set(&iopts, I_NREXT64)) {
+ fprintf(stderr,
+_("64 bit extent count not supported without CRC support\n"));
+ usage();
+ }
+ cli->sb_feat.nrext64 = false;
}
if (!cli->sb_feat.finobt) {
@@ -3172,6 +3192,8 @@ sb_set_features(
sbp->sb_features_incompat |= XFS_SB_FEAT_INCOMPAT_SPINODES;
}
+ if (fp->nrext64)
+ sbp->sb_features_incompat |= XFS_SB_FEAT_INCOMPAT_NREXT64;
}
/*
@@ -3937,6 +3959,7 @@ main(
.nodalign = false,
.nortalign = false,
.bigtime = true,
+ .nrext64 = false,
/*
* When we decide to enable a new feature by default,
* please remember to update the mkfs conf files.
--
2.35.1
