[PATCH 4/5] xfs: Remove mrlock wrapper

Matthew Wilcox (Oracle)
2023-09-07T17:48:04Z

mrlock was an rwsem wrapper that also recorded whether the lock was
held for read or write. Now that we can ask the generic code whether
the lock is held for read or write, we can remove this wrapper and use
an rwsem directly.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
fs/xfs/mrlock.h | 78 ----------------------------------------------
fs/xfs/xfs_inode.c | 18 +++++------
fs/xfs/xfs_inode.h | 2 +-
fs/xfs/xfs_iops.c | 4 +--
fs/xfs/xfs_linux.h | 2 +-
fs/xfs/xfs_super.c | 4 +--
6 files changed, 14 insertions(+), 94 deletions(-)
delete mode 100644 fs/xfs/mrlock.h

diff --git a/fs/xfs/mrlock.h b/fs/xfs/mrlock.h
deleted file mode 100644
index 79155eec341b..000000000000
--- a/fs/xfs/mrlock.h
+++ /dev/null
@@ -1,78 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (c) 2000-2006 Silicon Graphics, Inc.
- * All Rights Reserved.
- */
-#ifndef __XFS_SUPPORT_MRLOCK_H__
-#define __XFS_SUPPORT_MRLOCK_H__
-
-#include <linux/rwsem.h>
-
-typedef struct {
- struct rw_semaphore mr_lock;
-#if defined(DEBUG) || defined(XFS_WARN)
- int mr_writer;
-#endif
-} mrlock_t;
-
-#if defined(DEBUG) || defined(XFS_WARN)
-#define mrinit(mrp, name) \
- do { (mrp)->mr_writer = 0; init_rwsem(&(mrp)->mr_lock); } while (0)
-#else
-#define mrinit(mrp, name) \
- do { init_rwsem(&(mrp)->mr_lock); } while (0)
-#endif
-
-#define mrlock_init(mrp, t,n,s) mrinit(mrp, n)
-#define mrfree(mrp) do { } while (0)
-
-static inline void mraccess_nested(mrlock_t *mrp, int subclass)
-{
- down_read_nested(&mrp->mr_lock, subclass);
-}
-
-static inline void mrupdate_nested(mrlock_t *mrp, int subclass)
-{
- down_write_nested(&mrp->mr_lock, subclass);
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 1;
-#endif
-}
-
-static inline int mrtryaccess(mrlock_t *mrp)
-{
- return down_read_trylock(&mrp->mr_lock);
-}
-
-static inline int mrtryupdate(mrlock_t *mrp)
-{
- if (!down_write_trylock(&mrp->mr_lock))
- return 0;
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 1;
-#endif
- return 1;
-}
-
-static inline void mrunlock_excl(mrlock_t *mrp)
-{
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 0;
-#endif
- up_write(&mrp->mr_lock);
-}
-
-static inline void mrunlock_shared(mrlock_t *mrp)
-{
- up_read(&mrp->mr_lock);
-}
-
-static inline void mrdemote(mrlock_t *mrp)
-{
-#if defined(DEBUG) || defined(XFS_WARN)
- mrp->mr_writer = 0;
-#endif
- downgrade_write(&mrp->mr_lock);
-}
-
-#endif /* __XFS_SUPPORT_MRLOCK_H__ */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index e58d84d23f49..c3cd73c29868 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -208,9 +208,9 @@ xfs_ilock(
}

if (lock_flags & XFS_ILOCK_EXCL)
- mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
+ down_write_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
else if (lock_flags & XFS_ILOCK_SHARED)
- mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
+ down_read_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
}

/*
@@ -251,10 +251,10 @@ xfs_ilock_nowait(
}

if (lock_flags & XFS_ILOCK_EXCL) {
- if (!mrtryupdate(&ip->i_lock))
+ if (!down_write_trylock(&ip->i_lock))
goto out_undo_mmaplock;
} else if (lock_flags & XFS_ILOCK_SHARED) {
- if (!mrtryaccess(&ip->i_lock))
+ if (!down_read_trylock(&ip->i_lock))
goto out_undo_mmaplock;
}
return 1;
@@ -303,9 +303,9 @@ xfs_iunlock(
up_read(&VFS_I(ip)->i_mapping->invalidate_lock);

if (lock_flags & XFS_ILOCK_EXCL)
- mrunlock_excl(&ip->i_lock);
+ up_write(&ip->i_lock);
else if (lock_flags & XFS_ILOCK_SHARED)
- mrunlock_shared(&ip->i_lock);
+ up_read(&ip->i_lock);

trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
}
@@ -324,7 +324,7 @@ xfs_ilock_demote(
~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);

if (lock_flags & XFS_ILOCK_EXCL)
- mrdemote(&ip->i_lock);
+ downgrade_write(&ip->i_lock);
if (lock_flags & XFS_MMAPLOCK_EXCL)
downgrade_write(&VFS_I(ip)->i_mapping->invalidate_lock);
if (lock_flags & XFS_IOLOCK_EXCL)
@@ -363,9 +363,9 @@ xfs_isilocked(
uint lock_flags)
{
if (lock_flags & XFS_ILOCK_SHARED)
- return rwsem_is_locked(&ip->i_lock.mr_lock);
+ return rwsem_is_locked(&ip->i_lock);
if (lock_flags & XFS_ILOCK_EXCL)
- return rwsem_is_write_locked(&ip->i_lock.mr_lock);
+ return rwsem_is_write_locked(&ip->i_lock);
if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
return __xfs_rwsem_islocked(&VFS_I(ip)->i_mapping->invalidate_lock,
(lock_flags & XFS_MMAPLOCK_SHARED));
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 7547caf2f2ab..18941cd21b81 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -39,7 +39,7 @@ typedef struct xfs_inode {

/* Transaction and locking information. */
struct xfs_inode_log_item *i_itemp; /* logging information */
- mrlock_t i_lock; /* inode lock */
+ struct rw_semaphore i_lock; /* inode lock */
atomic_t i_pincount; /* inode pin count */
struct llist_node i_gclist; /* deferred inactivation list */

diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 2ededd3f6b8c..ba64c9c5d3ab 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1280,9 +1280,9 @@ xfs_setup_inode(
*/
lockdep_set_class(&inode->i_rwsem,
&inode->i_sb->s_type->i_mutex_dir_key);
- lockdep_set_class(&ip->i_lock.mr_lock, &xfs_dir_ilock_class);
+ lockdep_set_class(&ip->i_lock, &xfs_dir_ilock_class);
} else {
- lockdep_set_class(&ip->i_lock.mr_lock, &xfs_nondir_ilock_class);
+ lockdep_set_class(&ip->i_lock, &xfs_nondir_ilock_class);
}

/*
diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index e9d317a3dafe..15fdaef578fe 100644
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -22,7 +22,6 @@ typedef __u32 xfs_nlink_t;
#include "xfs_types.h"

#include "kmem.h"
-#include "mrlock.h"

#include <linux/semaphore.h>
#include <linux/mm.h>
@@ -51,6 +50,7 @@ typedef __u32 xfs_nlink_t;
#include <linux/notifier.h>
#include <linux/delay.h>
#include <linux/log2.h>
+#include <linux/rwsem.h>
#include <linux/spinlock.h>
#include <linux/random.h>
#include <linux/ctype.h>
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 1f77014c6e1a..d190afbcfe04 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -739,9 +739,7 @@ xfs_fs_inode_init_once(
/* xfs inode */
atomic_set(&ip->i_pincount, 0);
spin_lock_init(&ip->i_flags_lock);
-
- mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
- "xfsino", ip->i_ino);
+ init_rwsem(&ip->i_lock);
}

/*
--
2.40.1