[PATCH 12/24] xfs: define locking primitives for realtime groups

Darrick J. Wong
2024-08-23T00:17:47Z

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

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>
---
fs/xfs/libxfs/xfs_rtgroup.c | 49 +++++++++++++++++++++++++++++++++++++++++++
fs/xfs/libxfs/xfs_rtgroup.h | 16 ++++++++++++++
2 files changed, 65 insertions(+)

diff --git a/fs/xfs/libxfs/xfs_rtgroup.c b/fs/xfs/libxfs/xfs_rtgroup.c
index 2bad1ecb811eb..51f04cad5227c 100644
--- a/fs/xfs/libxfs/xfs_rtgroup.c
+++ b/fs/xfs/libxfs/xfs_rtgroup.c
@@ -194,3 +194,52 @@ xfs_rtgroup_extents(
ASSERT(xfs_has_rtgroups(mp));
return mp->m_sb.sb_rgextents;
}
+
+/* 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->rtg_mount);
+ else if (rtglock_flags & XFS_RTGLOCK_BITMAP_SHARED)
+ xfs_rtbitmap_lock_shared(rtg->rtg_mount, 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->rtg_mount);
+ else if (rtglock_flags & XFS_RTGLOCK_BITMAP_SHARED)
+ xfs_rtbitmap_unlock_shared(rtg->rtg_mount, 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/fs/xfs/libxfs/xfs_rtgroup.h b/fs/xfs/libxfs/xfs_rtgroup.h
index 2c09ecfc50328..d2eb2cd5775dd 100644
--- a/fs/xfs/libxfs/xfs_rtgroup.h
+++ b/fs/xfs/libxfs/xfs_rtgroup.h
@@ -205,8 +205,24 @@ xfs_daddr_to_rtb(

#ifdef CONFIG_XFS_RT
xfs_rtxnum_t xfs_rtgroup_extents(struct xfs_mount *mp, xfs_rgnumber_t rgno);
+
+/* 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
# define xfs_rtgroup_extents(mp, rgno) (0)
+# 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 */