5.10-stable review patch. If anyone has any objections, please let me know.
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From: Amir Goldstein amir73il@gmail.com
[ Upstream commit 11fa333b58ba1518e7c69fafb6513a0117f8fe33 ]
Instead of incrementing s_fsnotify_inode_refs when detaching connector from inode, increment it earlier when attaching connector to inode. Next patch is going to use s_fsnotify_inode_refs to count all objects with attached connectors.
Link: https://lore.kernel.org/r/20210810151220.285179-3-amir73il@gmail.com Reviewed-by: Matthew Bobrowski repnop@google.com Signed-off-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/notify/mark.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-)
diff --git a/fs/notify/mark.c b/fs/notify/mark.c index 3c8fc77d3f072..f6d1ad3ecca2a 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -169,6 +169,21 @@ static void fsnotify_connector_destroy_workfn(struct work_struct *work) } }
+static void fsnotify_get_inode_ref(struct inode *inode) +{ + ihold(inode); + atomic_long_inc(&inode->i_sb->s_fsnotify_inode_refs); +} + +static void fsnotify_put_inode_ref(struct inode *inode) +{ + struct super_block *sb = inode->i_sb; + + iput(inode); + if (atomic_long_dec_and_test(&sb->s_fsnotify_inode_refs)) + wake_up_var(&sb->s_fsnotify_inode_refs); +} + static void *fsnotify_detach_connector_from_object( struct fsnotify_mark_connector *conn, unsigned int *type) @@ -182,7 +197,6 @@ static void *fsnotify_detach_connector_from_object( if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) { inode = fsnotify_conn_inode(conn); inode->i_fsnotify_mask = 0; - atomic_long_inc(&inode->i_sb->s_fsnotify_inode_refs); } else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) { fsnotify_conn_mount(conn)->mnt_fsnotify_mask = 0; } else if (conn->type == FSNOTIFY_OBJ_TYPE_SB) { @@ -209,19 +223,12 @@ static void fsnotify_final_mark_destroy(struct fsnotify_mark *mark) /* Drop object reference originally held by a connector */ static void fsnotify_drop_object(unsigned int type, void *objp) { - struct inode *inode; - struct super_block *sb; - if (!objp) return; /* Currently only inode references are passed to be dropped */ if (WARN_ON_ONCE(type != FSNOTIFY_OBJ_TYPE_INODE)) return; - inode = objp; - sb = inode->i_sb; - iput(inode); - if (atomic_long_dec_and_test(&sb->s_fsnotify_inode_refs)) - wake_up_var(&sb->s_fsnotify_inode_refs); + fsnotify_put_inode_ref(objp); }
void fsnotify_put_mark(struct fsnotify_mark *mark) @@ -495,7 +502,7 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, } if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) { inode = fsnotify_conn_inode(conn); - ihold(inode); + fsnotify_get_inode_ref(inode); }
/* @@ -505,7 +512,7 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, if (cmpxchg(connp, NULL, conn)) { /* Someone else created list structure for us */ if (inode) - iput(inode); + fsnotify_put_inode_ref(inode); kmem_cache_free(fsnotify_mark_connector_cachep, conn); }