CIFS: Fix mounts if the client is low on credits

If the server doesn't grant us at least 3 credits during the mount
we won't be able to complete it because query path info operation
requires 3 credits. Use the cached file handle if possible to allow
the mount to succeed.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Pavel Shilovsky 2019-01-16 11:48:42 -08:00 committed by Steve French
parent 0fd1d37b05
commit 6a9cbdd1ce
1 changed files with 17 additions and 0 deletions

View File

@ -293,6 +293,8 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
int rc;
struct smb2_file_all_info *smb2_data;
__u32 create_options = 0;
struct cifs_fid fid;
bool no_cached_open = tcon->nohandlecache;
*adjust_tz = false;
*symlink = false;
@ -301,6 +303,21 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
GFP_KERNEL);
if (smb2_data == NULL)
return -ENOMEM;
/* If it is a root and its handle is cached then use it */
if (!strlen(full_path) && !no_cached_open) {
rc = open_shroot(xid, tcon, &fid);
if (rc)
goto out;
rc = SMB2_query_info(xid, tcon, fid.persistent_fid,
fid.volatile_fid, smb2_data);
close_shroot(&tcon->crfid);
if (rc)
goto out;
move_smb2_info_to_cifs(data, smb2_data);
goto out;
}
if (backup_cred(cifs_sb))
create_options |= CREATE_OPEN_BACKUP_INTENT;