Commit 11fa333b authored by Amir Goldstein's avatar Amir Goldstein Committed by Jan Kara
Browse files

fsnotify: count s_fsnotify_inode_refs for attached connectors 

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: default avatarMatthew Bobrowski <repnop@google.com>
Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent 09ddbe69

fs/notify/mark.c

+18 −11
Original line number Diff line number Diff line
@@ -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);

	}