Commit 5e9c89d4 authored by Ronnie Sahlberg's avatar Ronnie Sahlberg Committed by Steve French
Browse files

cifs: Grab a reference for the dentry of the cached directory during the lifetime of the cache 



We need to hold both a reference for the root/superblock as well as the directory that we
are caching. We need to drop these references before we call kill_anon_sb().

At this point, the root and the cached dentries are always the same but this will change
once we start caching other directories as well.

Signed-off-by: default avatarRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 269f67e1

fs/cifs/cifsfs.c

+17 −0
Original line number Diff line number Diff line
@@ -257,11 +257,28 @@ cifs_read_super(struct super_block *sb) 
static void cifs_kill_sb(struct super_block *sb)

{

	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);

	struct cifs_tcon *tcon;

	struct cached_fid *cfid;



	/*

	 * We ned to release all dentries for the cached directories

	 * before we kill the sb.

	 */

	if (cifs_sb->root) {

		dput(cifs_sb->root);

		cifs_sb->root = NULL;

	}

	tcon = cifs_sb_master_tcon(cifs_sb);

	if (tcon) {

		cfid = &tcon->crfid;

		mutex_lock(&cfid->fid_mutex);

		if (cfid->dentry) {



			dput(cfid->dentry);

			cfid->dentry = NULL;

		}

		mutex_unlock(&cfid->fid_mutex);

	}



	kill_anon_super(sb);

	cifs_umount(cifs_sb);

fs/cifs/cifsglob.h

+1 −0
Original line number Diff line number Diff line
@@ -992,6 +992,7 @@ struct cached_fid { 
	struct cifs_fid *fid;

	struct mutex fid_mutex;

	struct cifs_tcon *tcon;

	struct dentry *dentry;

	struct work_struct lease_break;

	struct smb2_file_all_info file_all_info;

};

fs/cifs/smb2ops.c

+9 −0
Original line number Diff line number Diff line
@@ -690,6 +690,10 @@ smb2_close_cached_fid(struct kref *ref) 
		cfid->is_valid = false;

		cfid->file_all_info_is_valid = false;

		cfid->has_lease = false;

		if (cfid->dentry) {

			dput(cfid->dentry);

			cfid->dentry = NULL;

		}

	}

}
@@ -747,6 +751,7 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, 
	__le16 utf16_path = 0; /* Null - since an open of top of share */

	u8 oplock = SMB2_OPLOCK_LEVEL_II;

	struct cifs_fid *pfid;

	struct dentry *dentry;



	if (tcon->nohandlecache)

		return -ENOTSUPP;
@@ -757,6 +762,8 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, 
	if (strlen(path))

		return -ENOENT;



	dentry = cifs_sb->root;



	mutex_lock(&tcon->crfid.fid_mutex);

	if (tcon->crfid.is_valid) {

		cifs_dbg(FYI, "found a cached root file handle\n");
@@ -881,6 +888,8 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon, 
	memcpy(tcon->crfid.fid, pfid, sizeof(struct cifs_fid));

	tcon->crfid.tcon = tcon;

	tcon->crfid.is_valid = true;

	tcon->crfid.dentry = dentry;

	dget(dentry);

	kref_init(&tcon->crfid.refcount);



	/* BB TBD check to see if oplock level check can be removed below */