fs/cifs: reopen persistent handles on reconnect

Continuous Availability features like persistent handles
require that clients reconnect their open files, not
just the sessions, soon after the network connection comes
back up, otherwise the server will throw away the state
(byte range locks, leases, deny modes) on those handles
after a timeout.

Add code to reconnect handles when use_persistent set
(e.g. Continuous Availability shares) after tree reconnect.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Germano Percossi <germano.percossi@citrix.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This commit is contained in:
Steve French 2016-09-22 19:23:56 -05:00
parent 3afca265b5
commit 52ace1ef12
3 changed files with 25 additions and 0 deletions

View file

@ -193,6 +193,8 @@ extern struct smb_vol *cifs_get_volume_info(char *mount_data,
extern int cifs_mount(struct cifs_sb_info *, struct smb_vol *);
extern void cifs_umount(struct cifs_sb_info *);
extern void cifs_mark_open_files_invalid(struct cifs_tcon *tcon);
extern void cifs_reopen_persistent_handles(struct cifs_tcon *tcon);
extern bool cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset,
__u64 length, __u8 type,
struct cifsLockInfo **conf_lock,

View file

@ -760,6 +760,24 @@ int cifs_close(struct inode *inode, struct file *file)
return 0;
}
void
cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
{
struct cifsFileInfo *open_file = NULL;
struct list_head *tmp;
struct list_head *tmp1;
/* list all files open on tree connection, reopen resilient handles */
spin_lock(&tcon->open_file_lock);
list_for_each_safe(tmp, tmp1, &tcon->openFileList) {
open_file = list_entry(tmp, struct cifsFileInfo, tlist);
spin_unlock(&tcon->open_file_lock);
cifs_reopen_file(open_file, false /* do not flush */);
spin_lock(&tcon->open_file_lock);
}
spin_unlock(&tcon->open_file_lock);
}
int cifs_closedir(struct inode *inode, struct file *file)
{
int rc = 0;

View file

@ -250,8 +250,13 @@ smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon)
}
cifs_mark_open_files_invalid(tcon);
rc = SMB2_tcon(0, tcon->ses, tcon->treeName, tcon, nls_codepage);
mutex_unlock(&tcon->ses->session_mutex);
if (tcon->use_persistent)
cifs_reopen_persistent_handles(tcon);
cifs_dbg(FYI, "reconnect tcon rc = %d\n", rc);
if (rc)
goto out;