[PATCH 02/13] xfs: refactor realtime inode locking

Christoph Hellwig
2024-03-27T11:03:30Z

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

Create helper functions to deal with locking realtime metadata inodes.
This enables us to maintain correct locking order once we start adding
the realtime rmap and refcount btree inodes.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/libxfs/xfs_bmap.c | 7 ++---
fs/xfs/libxfs/xfs_rtbitmap.c | 57 ++++++++++++++++++++++++++++++++++++
fs/xfs/libxfs/xfs_rtbitmap.h | 17 +++++++++++
fs/xfs/scrub/common.c | 1 +
fs/xfs/scrub/fscounters.c | 4 +--
fs/xfs/xfs_fsmap.c | 4 +--
fs/xfs/xfs_rtalloc.c | 20 ++++---------
7 files changed, 87 insertions(+), 23 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 656c95a22f2e6d..09d4b730ee9709 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -5416,12 +5416,9 @@ __xfs_bunmapi(

if (isrt) {
/*
- * Synchronize by locking the bitmap inode.
+ * Synchronize by locking the realtime bitmap.
*/
- xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
- xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
- xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
- xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
+ xfs_rtbitmap_lock(tp, mp);
}

extno = 0;
diff --git a/fs/xfs/libxfs/xfs_rtbitmap.c b/fs/xfs/libxfs/xfs_rtbitmap.c
index f246d6dbf4eca8..386b672c505896 100644
--- a/fs/xfs/libxfs/xfs_rtbitmap.c
+++ b/fs/xfs/libxfs/xfs_rtbitmap.c
@@ -1168,3 +1168,60 @@ xfs_rtsummary_wordcount(
blocks = xfs_rtsummary_blockcount(mp, rsumlevels, rbmblocks);
return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
}
+
+/*
+ * Lock both realtime free space metadata inodes for a freespace update. If a
+ * transaction is given, the inodes will be joined to the transaction and the
+ * ILOCKs will be released on transaction commit.
+ */
+void
+xfs_rtbitmap_lock(
+ struct xfs_trans *tp,
+ struct xfs_mount *mp)
+{
+ xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
+ if (tp)
+ xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
+
+ xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL | XFS_ILOCK_RTSUM);
+ if (tp)
+ xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
+}
+
+/* Unlock both realtime free space metadata inodes after a freespace update. */
+void
+xfs_rtbitmap_unlock(
+ struct xfs_mount *mp)
+{
+ xfs_iunlock(mp->m_rsumip, XFS_ILOCK_EXCL | XFS_ILOCK_RTSUM);
+ xfs_iunlock(mp->m_rbmip, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
+}
+
+/*
+ * Lock the realtime free space metadata inodes for a freespace scan. Callers
+ * must walk metadata blocks in order of increasing file offset.
+ */
+void
+xfs_rtbitmap_lock_shared(
+ struct xfs_mount *mp,
+ unsigned int rbmlock_flags)
+{
+ if (rbmlock_flags & XFS_RBMLOCK_BITMAP)
+ xfs_ilock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+
+ if (rbmlock_flags & XFS_RBMLOCK_SUMMARY)
+ xfs_ilock(mp->m_rsumip, XFS_ILOCK_SHARED | XFS_ILOCK_RTSUM);
+}
+
+/* Unlock the realtime free space metadata inodes after a freespace scan. */
+void
+xfs_rtbitmap_unlock_shared(
+ struct xfs_mount *mp,
+ unsigned int rbmlock_flags)
+{
+ if (rbmlock_flags & XFS_RBMLOCK_SUMMARY)
+ xfs_iunlock(mp->m_rsumip, XFS_ILOCK_SHARED | XFS_ILOCK_RTSUM);
+
+ if (rbmlock_flags & XFS_RBMLOCK_BITMAP)
+ xfs_iunlock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+}
diff --git a/fs/xfs/libxfs/xfs_rtbitmap.h b/fs/xfs/libxfs/xfs_rtbitmap.h
index 152a66750af554..6186585f2c376d 100644
--- a/fs/xfs/libxfs/xfs_rtbitmap.h
+++ b/fs/xfs/libxfs/xfs_rtbitmap.h
@@ -360,6 +360,19 @@ xfs_filblks_t xfs_rtsummary_blockcount(struct xfs_mount *mp,
unsigned int rsumlevels, xfs_extlen_t rbmblocks);
unsigned long long xfs_rtsummary_wordcount(struct xfs_mount *mp,
unsigned int rsumlevels, xfs_extlen_t rbmblocks);
+
+void xfs_rtbitmap_lock(struct xfs_trans *tp, struct xfs_mount *mp);
+void xfs_rtbitmap_unlock(struct xfs_mount *mp);
+
+/* Lock the rt bitmap inode in shared mode */
+#define XFS_RBMLOCK_BITMAP (1U << 0)
+/* Lock the rt summary inode in shared mode */
+#define XFS_RBMLOCK_SUMMARY (1U << 1)
+
+void xfs_rtbitmap_lock_shared(struct xfs_mount *mp,
+ unsigned int rbmlock_flags);
+void xfs_rtbitmap_unlock_shared(struct xfs_mount *mp,
+ unsigned int rbmlock_flags);
#else /* CONFIG_XFS_RT */
# define xfs_rtfree_extent(t,b,l) (-ENOSYS)
# define xfs_rtfree_blocks(t,rb,rl) (-ENOSYS)
@@ -378,6 +391,10 @@ xfs_rtbitmap_blockcount(struct xfs_mount *mp, xfs_rtbxlen_t rtextents)
# define xfs_rtbitmap_wordcount(mp, r) (0)
# define xfs_rtsummary_blockcount(mp, l, b) (0)
# define xfs_rtsummary_wordcount(mp, l, b) (0)
+# define xfs_rtbitmap_lock(tp, mp) do { } while (0)
+# define xfs_rtbitmap_unlock(mp) do { } while (0)
+# define xfs_rtbitmap_lock_shared(mp, lf) do { } while (0)
+# define xfs_rtbitmap_unlock_shared(mp, lf) do { } while (0)
#endif /* CONFIG_XFS_RT */

#endif /* __XFS_RTBITMAP_H__ */
diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
index 47a20cf5205f00..48887a163e6a3b 100644
--- a/fs/xfs/scrub/common.c
+++ b/fs/xfs/scrub/common.c
@@ -31,6 +31,7 @@
#include "xfs_ag.h"
#include "xfs_error.h"
#include "xfs_quota.h"
+#include "xfs_rtbitmap.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/trace.h"
diff --git a/fs/xfs/scrub/fscounters.c b/fs/xfs/scrub/fscounters.c
index d310737c882367..2b4bd2eb71b57d 100644
--- a/fs/xfs/scrub/fscounters.c
+++ b/fs/xfs/scrub/fscounters.c
@@ -415,7 +415,7 @@ xchk_fscount_count_frextents(
if (!xfs_has_realtime(mp))
return 0;

- xfs_ilock(sc->mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+ xfs_rtbitmap_lock_shared(sc->mp, XFS_RBMLOCK_BITMAP);
error = xfs_rtalloc_query_all(sc->mp, sc->tp,
xchk_fscount_add_frextent, fsc);
if (error) {
@@ -424,7 +424,7 @@ xchk_fscount_count_frextents(
}

out_unlock:
- xfs_iunlock(sc->mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+ xfs_rtbitmap_unlock_shared(sc->mp, XFS_RBMLOCK_BITMAP);
return error;
}
#else
diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c
index de59eec7476575..85dbb46452ca0b 100644
--- a/fs/xfs/xfs_fsmap.c
+++ b/fs/xfs/xfs_fsmap.c
@@ -533,7 +533,7 @@ xfs_getfsmap_rtdev_rtbitmap(
trace_xfs_fsmap_low_key_linear(mp, info->dev, start_rtb);
trace_xfs_fsmap_high_key_linear(mp, info->dev, end_rtb);

- xfs_ilock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+ xfs_rtbitmap_lock_shared(mp, XFS_RBMLOCK_BITMAP);

/*
* Set up query parameters to return free rtextents covering the range
@@ -557,7 +557,7 @@ xfs_getfsmap_rtdev_rtbitmap(
if (error)
goto err;
err:
- xfs_iunlock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+ xfs_rtbitmap_unlock_shared(mp, XFS_RBMLOCK_BITMAP);
return error;
}
#endif /* CONFIG_XFS_RT */
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index e66f9bd5de5cff..86f928d30feda9 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -957,10 +957,10 @@ xfs_growfs_rt(
nargs.tp = tp;

/*
- * Lock out other callers by grabbing the bitmap inode lock.
+ * Lock out other callers by grabbing the bitmap and summary
+ * inode locks and joining them to the transaction.
*/
- xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
- xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
+ xfs_rtbitmap_lock(tp, mp);
/*
* Update the bitmap inode's size ondisk and incore. We need
* to update the incore size so that inode inactivation won't
@@ -970,11 +970,6 @@ xfs_growfs_rt(
nsbp->sb_rbmblocks * nsbp->sb_blocksize;
i_size_write(VFS_I(mp->m_rbmip), mp->m_rbmip->i_disk_size);
xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
- /*
- * Get the summary inode into the transaction.
- */
- xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL | XFS_ILOCK_RTSUM);
- xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
/*
* Update the summary inode's size. We need to update the
* incore size so that inode inactivation won't punch what it
@@ -1142,10 +1137,10 @@ xfs_rtalloc_reinit_frextents(
uint64_t val = 0;
int error;

- xfs_ilock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+ xfs_rtbitmap_lock_shared(mp, XFS_RBMLOCK_BITMAP);
error = xfs_rtalloc_query_all(mp, NULL, xfs_rtalloc_count_frextent,
&val);
- xfs_iunlock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
+ xfs_rtbitmap_unlock_shared(mp, XFS_RBMLOCK_BITMAP);
if (error)
return error;

@@ -1382,10 +1377,7 @@ xfs_bmap_rtalloc(
* Lock out modifications to both the RT bitmap and summary inodes
*/
if (!rtlocked) {
- xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
- xfs_trans_ijoin(ap->tp, mp->m_rbmip, XFS_ILOCK_EXCL);
- xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
- xfs_trans_ijoin(ap->tp, mp->m_rsumip, XFS_ILOCK_EXCL);
+ xfs_rtbitmap_lock(ap->tp, mp);
rtlocked = true;
}

--
2.39.2