[PATCH 02/46] xfs: define locking primitives for realtime groups

Darrick J. Wong
2024-12-06T23:51:53Z

From: Darrick J. Wong <djwong@kernel.org>

Source kernel commit: 0e4875b3fb24c5bfdf685876c76713cda5a23b65

Define helper functions to lock all metadata inodes related to a
realtime group. There's not much to look at now, but this will become
important when we add per-rtgroup metadata files and online fsck code
for them.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
libxfs/xfs_rtgroup.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
libxfs/xfs_rtgroup.h | 16 ++++++++++++++++
2 files changed, 65 insertions(+)

diff --git a/libxfs/xfs_rtgroup.c b/libxfs/xfs_rtgroup.c
index 88f31384bf6961..5c8e269b62dbc4 100644
--- a/libxfs/xfs_rtgroup.c
+++ b/libxfs/xfs_rtgroup.c
@@ -147,3 +147,52 @@ xfs_update_last_rtgroup_size(
xfs_rtgroup_rele(rtg);
return 0;
}
+
+/* Lock metadata inodes associated with this rt group. */
+void
+xfs_rtgroup_lock(
+ struct xfs_rtgroup *rtg,
+ unsigned int rtglock_flags)
+{
+ ASSERT(!(rtglock_flags & ~XFS_RTGLOCK_ALL_FLAGS));
+ ASSERT(!(rtglock_flags & XFS_RTGLOCK_BITMAP_SHARED) ||
+ !(rtglock_flags & XFS_RTGLOCK_BITMAP));
+
+ if (rtglock_flags & XFS_RTGLOCK_BITMAP)
+ xfs_rtbitmap_lock(rtg_mount(rtg));
+ else if (rtglock_flags & XFS_RTGLOCK_BITMAP_SHARED)
+ xfs_rtbitmap_lock_shared(rtg_mount(rtg), XFS_RBMLOCK_BITMAP);
+}
+
+/* Unlock metadata inodes associated with this rt group. */
+void
+xfs_rtgroup_unlock(
+ struct xfs_rtgroup *rtg,
+ unsigned int rtglock_flags)
+{
+ ASSERT(!(rtglock_flags & ~XFS_RTGLOCK_ALL_FLAGS));
+ ASSERT(!(rtglock_flags & XFS_RTGLOCK_BITMAP_SHARED) ||
+ !(rtglock_flags & XFS_RTGLOCK_BITMAP));
+
+ if (rtglock_flags & XFS_RTGLOCK_BITMAP)
+ xfs_rtbitmap_unlock(rtg_mount(rtg));
+ else if (rtglock_flags & XFS_RTGLOCK_BITMAP_SHARED)
+ xfs_rtbitmap_unlock_shared(rtg_mount(rtg), XFS_RBMLOCK_BITMAP);
+}
+
+/*
+ * Join realtime group metadata inodes to the transaction. The ILOCKs will be
+ * released on transaction commit.
+ */
+void
+xfs_rtgroup_trans_join(
+ struct xfs_trans *tp,
+ struct xfs_rtgroup *rtg,
+ unsigned int rtglock_flags)
+{
+ ASSERT(!(rtglock_flags & ~XFS_RTGLOCK_ALL_FLAGS));
+ ASSERT(!(rtglock_flags & XFS_RTGLOCK_BITMAP_SHARED));
+
+ if (rtglock_flags & XFS_RTGLOCK_BITMAP)
+ xfs_rtbitmap_trans_join(tp);
+}
diff --git a/libxfs/xfs_rtgroup.h b/libxfs/xfs_rtgroup.h
index 8872c27a9585fd..7d82eb753fd097 100644
--- a/libxfs/xfs_rtgroup.h
+++ b/libxfs/xfs_rtgroup.h
@@ -197,6 +197,19 @@ xfs_rtxnum_t xfs_rtgroup_extents(struct xfs_mount *mp, xfs_rgnumber_t rgno);

int xfs_update_last_rtgroup_size(struct xfs_mount *mp,
xfs_rgnumber_t prev_rgcount);
+
+/* Lock the rt bitmap inode in exclusive mode */
+#define XFS_RTGLOCK_BITMAP (1U << 0)
+/* Lock the rt bitmap inode in shared mode */
+#define XFS_RTGLOCK_BITMAP_SHARED (1U << 1)
+
+#define XFS_RTGLOCK_ALL_FLAGS (XFS_RTGLOCK_BITMAP | \
+ XFS_RTGLOCK_BITMAP_SHARED)
+
+void xfs_rtgroup_lock(struct xfs_rtgroup *rtg, unsigned int rtglock_flags);
+void xfs_rtgroup_unlock(struct xfs_rtgroup *rtg, unsigned int rtglock_flags);
+void xfs_rtgroup_trans_join(struct xfs_trans *tp, struct xfs_rtgroup *rtg,
+ unsigned int rtglock_flags);
#else
static inline void xfs_free_rtgroups(struct xfs_mount *mp,
xfs_rgnumber_t first_rgno, xfs_rgnumber_t end_rgno)
@@ -212,6 +225,9 @@ static inline int xfs_initialize_rtgroups(struct xfs_mount *mp,

# define xfs_rtgroup_extents(mp, rgno) (0)
# define xfs_update_last_rtgroup_size(mp, rgno) (-EOPNOTSUPP)
+# define xfs_rtgroup_lock(rtg, gf) ((void)0)
+# define xfs_rtgroup_unlock(rtg, gf) ((void)0)
+# define xfs_rtgroup_trans_join(tp, rtg, gf) ((void)0)
#endif /* CONFIG_XFS_RT */

#endif /* __LIBXFS_RTGROUP_H */