summaryrefslogtreecommitdiff
path: root/fs/cifs
diff options
context:
space:
mode:
authorRonnie Sahlberg <lsahlber@redhat.com>2018-07-31 08:48:22 +1000
committerSteve French <stfrench@microsoft.com>2018-08-07 14:20:22 -0500
commit9da6ec7775d2cd76df53fbf4f1f35f6d490204f5 (patch)
tree4b94d5c7acde55bde6f42779a986c9de3268d513 /fs/cifs
parentbf1fdeb7899a86adfbe0b521bee5cf78bb870a14 (diff)
cifs: use a refcount to protect open/closing the cached file handle
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com> Cc: <stable@vger.kernel.org>
Diffstat (limited to 'fs/cifs')
-rw-r--r--fs/cifs/cifsglob.h1
-rw-r--r--fs/cifs/smb2inode.c4
-rw-r--r--fs/cifs/smb2ops.c31
-rw-r--r--fs/cifs/smb2proto.h1
4 files changed, 31 insertions, 6 deletions
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 8826bc0a9b15..0e6fd5fa4eb6 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -907,6 +907,7 @@ cap_unix(struct cifs_ses *ses)
struct cached_fid {
bool is_valid:1; /* Do we have a useable root fid */
+ struct kref refcount;
struct cifs_fid *fid;
struct mutex fid_mutex;
struct cifs_tcon *tcon;
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
index d01ad706d7fc..f22cbc0d1869 100644
--- a/fs/cifs/smb2inode.c
+++ b/fs/cifs/smb2inode.c
@@ -120,7 +120,9 @@ smb2_open_op_close(const unsigned int xid, struct cifs_tcon *tcon,
break;
}
- if (use_cached_root_handle == false)
+ if (use_cached_root_handle)
+ close_shroot(&tcon->crfid);
+ else
rc = SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
if (tmprc)
rc = tmprc;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 314556c083f3..8929426ddaa6 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -470,21 +470,36 @@ out:
return rc;
}
-void
-smb2_cached_lease_break(struct work_struct *work)
+static void
+smb2_close_cached_fid(struct kref *ref)
{
- struct cached_fid *cfid = container_of(work,
- struct cached_fid, lease_break);
- mutex_lock(&cfid->fid_mutex);
+ struct cached_fid *cfid = container_of(ref, struct cached_fid,
+ refcount);
+
if (cfid->is_valid) {
cifs_dbg(FYI, "clear cached root file handle\n");
SMB2_close(0, cfid->tcon, cfid->fid->persistent_fid,
cfid->fid->volatile_fid);
cfid->is_valid = false;
}
+}
+
+void close_shroot(struct cached_fid *cfid)
+{
+ mutex_lock(&cfid->fid_mutex);
+ kref_put(&cfid->refcount, smb2_close_cached_fid);
mutex_unlock(&cfid->fid_mutex);
}
+void
+smb2_cached_lease_break(struct work_struct *work)
+{
+ struct cached_fid *cfid = container_of(work,
+ struct cached_fid, lease_break);
+
+ close_shroot(cfid);
+}
+
/*
* Open the directory at the root of a share
*/
@@ -499,6 +514,7 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid)
if (tcon->crfid.is_valid) {
cifs_dbg(FYI, "found a cached root file handle\n");
memcpy(pfid, tcon->crfid.fid, sizeof(struct cifs_fid));
+ kref_get(&tcon->crfid.refcount);
mutex_unlock(&tcon->crfid.fid_mutex);
return 0;
}
@@ -515,6 +531,8 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid)
memcpy(tcon->crfid.fid, pfid, sizeof(struct cifs_fid));
tcon->crfid.tcon = tcon;
tcon->crfid.is_valid = true;
+ kref_init(&tcon->crfid.refcount);
+ kref_get(&tcon->crfid.refcount);
}
mutex_unlock(&tcon->crfid.fid_mutex);
return rc;
@@ -558,6 +576,9 @@ smb3_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon)
FS_SECTOR_SIZE_INFORMATION); /* SMB3 specific */
if (no_cached_open)
SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
+ else
+ close_shroot(&tcon->crfid);
+
return;
}
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index 98d9b30c16a6..19aa483395c7 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -68,6 +68,7 @@ extern int smb3_handle_read_data(struct TCP_Server_Info *server,
extern int open_shroot(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_fid *pfid);
+extern void close_shroot(struct cached_fid *cfid);
extern void move_smb2_info_to_cifs(FILE_ALL_INFO *dst,
struct smb2_file_all_info *src);
extern int smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,