[PATCH 37/56] xfs: add realtime refcount btree inode to metadata directory

Darrick J. Wong
2025-02-06T22:44:47Z

Source kernel commit: eaed472c40527e526217aff3737816b44b08b363

Add a metadir path to select the realtime refcount btree inode and load
it at mount time. The rtrefcountbt inode will have a unique extent format
code, which means that we also have to update the inode validation and
flush routines to look for it.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
libxfs/xfs_format.h | 4 +++-
libxfs/xfs_inode_buf.c | 5 +++++
libxfs/xfs_inode_fork.c | 6 ++++++
libxfs/xfs_rtgroup.c | 7 +++++++
libxfs/xfs_rtgroup.h | 6 ++++++
libxfs/xfs_rtrefcount_btree.c | 6 +++---
6 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/libxfs/xfs_format.h b/libxfs/xfs_format.h
index 17f7c0d1aaa452..b6828f92c131fb 100644
--- a/libxfs/xfs_format.h
+++ b/libxfs/xfs_format.h
@@ -858,6 +858,7 @@ enum xfs_metafile_type {
XFS_METAFILE_RTBITMAP, /* rt bitmap */
XFS_METAFILE_RTSUMMARY, /* rt summary */
XFS_METAFILE_RTRMAP, /* rt rmap */
+ XFS_METAFILE_RTREFCOUNT, /* rt refcount */

XFS_METAFILE_MAX
} __packed;
@@ -870,7 +871,8 @@ enum xfs_metafile_type {
{ XFS_METAFILE_PRJQUOTA, "prjquota" }, \
{ XFS_METAFILE_RTBITMAP, "rtbitmap" }, \
{ XFS_METAFILE_RTSUMMARY, "rtsummary" }, \
- { XFS_METAFILE_RTRMAP, "rtrmap" }
+ { XFS_METAFILE_RTRMAP, "rtrmap" }, \
+ { XFS_METAFILE_RTREFCOUNT, "rtrefcount" }

/*
* On-disk inode structure.
diff --git a/libxfs/xfs_inode_buf.c b/libxfs/xfs_inode_buf.c
index 0278fbb6379701..0be0625857002c 100644
--- a/libxfs/xfs_inode_buf.c
+++ b/libxfs/xfs_inode_buf.c
@@ -453,6 +453,11 @@ xfs_dinode_verify_fork(
if (!xfs_has_rmapbt(mp))
return __this_address;
break;
+ case XFS_METAFILE_RTREFCOUNT:
+ /* same comment about growfs and rmap inodes applies */
+ if (!xfs_has_reflink(mp))
+ return __this_address;
+ break;
default:
return __this_address;
}
diff --git a/libxfs/xfs_inode_fork.c b/libxfs/xfs_inode_fork.c
index e4f866969bf1b6..f690c746805fad 100644
--- a/libxfs/xfs_inode_fork.c
+++ b/libxfs/xfs_inode_fork.c
@@ -270,6 +270,9 @@ xfs_iformat_data_fork(
switch (ip->i_metatype) {
case XFS_METAFILE_RTRMAP:
return xfs_iformat_rtrmap(ip, dip);
+ case XFS_METAFILE_RTREFCOUNT:
+ ASSERT(0); /* to be implemented later */
+ return -EFSCORRUPTED;
default:
break;
}
@@ -618,6 +621,9 @@ xfs_iflush_fork(
case XFS_METAFILE_RTRMAP:
xfs_iflush_rtrmap(ip, dip);
break;
+ case XFS_METAFILE_RTREFCOUNT:
+ ASSERT(0); /* to be implemented later */
+ break;
default:
ASSERT(0);
break;
diff --git a/libxfs/xfs_rtgroup.c b/libxfs/xfs_rtgroup.c
index 7e69b6bf96f1ac..f7bacce8500c0c 100644
--- a/libxfs/xfs_rtgroup.c
+++ b/libxfs/xfs_rtgroup.c
@@ -364,6 +364,13 @@ static const struct xfs_rtginode_ops xfs_rtginode_ops[XFS_RTGI_MAX] = {
.enabled = xfs_has_rmapbt,
.create = xfs_rtrmapbt_create,
},
+ [XFS_RTGI_REFCOUNT] = {
+ .name = "refcount",
+ .metafile_type = XFS_METAFILE_RTREFCOUNT,
+ .fmt_mask = 1U << XFS_DINODE_FMT_META_BTREE,
+ /* same comment about growfs and rmap inodes applies here */
+ .enabled = xfs_has_reflink,
+ },
};

/* Return the shortname of this rtgroup inode. */
diff --git a/libxfs/xfs_rtgroup.h b/libxfs/xfs_rtgroup.h
index 6ff222a053674d..2663f2d849e295 100644
--- a/libxfs/xfs_rtgroup.h
+++ b/libxfs/xfs_rtgroup.h
@@ -15,6 +15,7 @@ enum xfs_rtg_inodes {
XFS_RTGI_BITMAP, /* allocation bitmap */
XFS_RTGI_SUMMARY, /* allocation summary */
XFS_RTGI_RMAP, /* rmap btree inode */
+ XFS_RTGI_REFCOUNT, /* refcount btree inode */

XFS_RTGI_MAX,
};
@@ -80,6 +81,11 @@ static inline struct xfs_inode *rtg_rmap(const struct xfs_rtgroup *rtg)
return rtg->rtg_inodes[XFS_RTGI_RMAP];
}

+static inline struct xfs_inode *rtg_refcount(const struct xfs_rtgroup *rtg)
+{
+ return rtg->rtg_inodes[XFS_RTGI_REFCOUNT];
+}
+
/* Passive rtgroup references */
static inline struct xfs_rtgroup *
xfs_rtgroup_get(
diff --git a/libxfs/xfs_rtrefcount_btree.c b/libxfs/xfs_rtrefcount_btree.c
index ea05b1a48eab62..46c62bd63458f4 100644
--- a/libxfs/xfs_rtrefcount_btree.c
+++ b/libxfs/xfs_rtrefcount_btree.c
@@ -24,6 +24,7 @@
#include "xfs_cksum.h"
#include "xfs_rtgroup.h"
#include "xfs_rtbitmap.h"
+#include "xfs_metafile.h"

static struct kmem_cache *xfs_rtrefcountbt_cur_cache;

@@ -279,12 +280,10 @@ xfs_rtrefcountbt_init_cursor(
struct xfs_trans *tp,
struct xfs_rtgroup *rtg)
{
- struct xfs_inode *ip = NULL;
+ struct xfs_inode *ip = rtg_refcount(rtg);
struct xfs_mount *mp = rtg_mount(rtg);
struct xfs_btree_cur *cur;

- return NULL; /* XXX */
-
xfs_assert_ilocked(ip, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL);

cur = xfs_btree_alloc_cursor(mp, tp, &xfs_rtrefcountbt_ops,
@@ -314,6 +313,7 @@ xfs_rtrefcountbt_commit_staged_btree(
int flags = XFS_ILOG_CORE | XFS_ILOG_DBROOT;

ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
+ ASSERT(ifake->if_fork->if_format == XFS_DINODE_FMT_META_BTREE);

/*
* Free any resources hanging off the real fork, then shallow-copy the