[PATCH linux dev-6.1 1/5] fs: uninline inode_query_iversion

Stefan Berger stefanb at linux.ibm.com
Tue Sep 5 23:13:57 AEST 2023


From: Jeff Layton <jlayton at kernel.org>

Reviewed-by: NeilBrown <neilb at suse.de>
Reviewed-by: Jan Kara <jack at suse.cz>
Reviewed-by: Christian Brauner <brauner at kernel.org>
Signed-off-by: Jeff Layton <jlayton at kernel.org>
---
 fs/libfs.c               | 36 ++++++++++++++++++++++++++++++++++++
 include/linux/iversion.h | 38 ++------------------------------------
 2 files changed, 38 insertions(+), 36 deletions(-)

diff --git a/fs/libfs.c b/fs/libfs.c
index aada4e7c8713..17ecc47696e1 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1582,3 +1582,39 @@ bool inode_maybe_inc_iversion(struct inode *inode, bool force)
 	return true;
 }
 EXPORT_SYMBOL(inode_maybe_inc_iversion);
+
+/**
+ * inode_query_iversion - read i_version for later use
+ * @inode: inode from which i_version should be read
+ *
+ * Read the inode i_version counter. This should be used by callers that wish
+ * to store the returned i_version for later comparison. This will guarantee
+ * that a later query of the i_version will result in a different value if
+ * anything has changed.
+ *
+ * In this implementation, we fetch the current value, set the QUERIED flag and
+ * then try to swap it into place with a cmpxchg, if it wasn't already set. If
+ * that fails, we try again with the newly fetched value from the cmpxchg.
+ */
+u64 inode_query_iversion(struct inode *inode)
+{
+	u64 cur, new;
+
+	cur = inode_peek_iversion_raw(inode);
+	do {
+		/* If flag is already set, then no need to swap */
+		if (cur & I_VERSION_QUERIED) {
+			/*
+			 * This barrier (and the implicit barrier in the
+			 * cmpxchg below) pairs with the barrier in
+			 * inode_maybe_inc_iversion().
+			 */
+			smp_mb();
+			break;
+		}
+
+		new = cur | I_VERSION_QUERIED;
+	} while (!atomic64_try_cmpxchg(&inode->i_version, &cur, new));
+	return cur >> I_VERSION_QUERIED_SHIFT;
+}
+EXPORT_SYMBOL(inode_query_iversion);
diff --git a/include/linux/iversion.h b/include/linux/iversion.h
index e27bd4f55d84..6755d8b4f20b 100644
--- a/include/linux/iversion.h
+++ b/include/linux/iversion.h
@@ -234,42 +234,6 @@ inode_peek_iversion(const struct inode *inode)
 	return inode_peek_iversion_raw(inode) >> I_VERSION_QUERIED_SHIFT;
 }
 
-/**
- * inode_query_iversion - read i_version for later use
- * @inode: inode from which i_version should be read
- *
- * Read the inode i_version counter. This should be used by callers that wish
- * to store the returned i_version for later comparison. This will guarantee
- * that a later query of the i_version will result in a different value if
- * anything has changed.
- *
- * In this implementation, we fetch the current value, set the QUERIED flag and
- * then try to swap it into place with a cmpxchg, if it wasn't already set. If
- * that fails, we try again with the newly fetched value from the cmpxchg.
- */
-static inline u64
-inode_query_iversion(struct inode *inode)
-{
-	u64 cur, new;
-
-	cur = inode_peek_iversion_raw(inode);
-	do {
-		/* If flag is already set, then no need to swap */
-		if (cur & I_VERSION_QUERIED) {
-			/*
-			 * This barrier (and the implicit barrier in the
-			 * cmpxchg below) pairs with the barrier in
-			 * inode_maybe_inc_iversion().
-			 */
-			smp_mb();
-			break;
-		}
-
-		new = cur | I_VERSION_QUERIED;
-	} while (!atomic64_try_cmpxchg(&inode->i_version, &cur, new));
-	return cur >> I_VERSION_QUERIED_SHIFT;
-}
-
 /*
  * For filesystems without any sort of change attribute, the best we can
  * do is fake one up from the ctime:
@@ -283,6 +247,8 @@ static inline u64 time_to_chattr(struct timespec64 *t)
 	return chattr;
 }
 
+u64 inode_query_iversion(struct inode *inode);
+
 /**
  * inode_eq_iversion_raw - check whether the raw i_version counter has changed
  * @inode: inode to check
-- 
2.40.1



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