cifs: remove old dead code

While reviewing a patch clarifying locks and locking hierarchy I
realized some locks were unused.

This commit removes old data and code that isn't actually used
anywhere, or hidden in ifdefs which cannot be enabled from the kernel
config.

* The uid/gid trees and associated locks are left-overs from when
  uid/sid mapping had an extra caching layer on top of the keyring and
  are now unused.
  See commit faa65f07 ("cifs: simplify id_to_sid and sid_to_id mapping code")
  from 2012.

* cifs_oplock_break_ops is a left-over from when slow_work was remplaced
  by regular workqueue and is now unused.
  See commit 9b646972 ("cifs: use workqueue instead of slow-work")
  from 2010.

* CIFSSMBSetAttrLegacy is SMB1 cruft dealing with some legacy
  NT4/Win9x behaviour.

* Remove CONFIG_CIFS_DNOTIFY_EXPERIMENTAL left-overs. This was already
  partially removed in 392e1c5d ("cifs: rename and clarify CIFS_ASYNC_OP and CIFS_NO_RESP")
  from 2019. Kill it completely.

* Another candidate that was considered but spared is
  CONFIG_CIFS_NFSD_EXPORT which has an empty implementation and cannot
  be enabled by a config option (although it is listed but disabled with
  "BROKEN" as a dep). It's unclear whether this could even function
  today in its current form but it has it's own .c file and Kconfig
  entry which is a bit more involved to remove and might make a come
  back?
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/cifsfs.c

@@ -1526,10 +1526,6 @@ init_cifs(void)
 	int rc = 0;
 	cifs_proc_init();
 	INIT_LIST_HEAD(&cifs_tcp_ses_list);
-#ifdef CONFIG_CIFS_DNOTIFY_EXPERIMENTAL /* unused temporarily */
-	INIT_LIST_HEAD(&GlobalDnotifyReqList);
-	INIT_LIST_HEAD(&GlobalDnotifyRsp_Q);
-#endif /* was needed for dnotify, and will be needed for inotify when VFS fix */
 /*
  *  Initialize Global counters
  */

fs/cifs/cifsglob.h

@@ -1824,13 +1824,6 @@ GLOBAL_EXTERN struct list_head		cifs_tcp_ses_list;
  */
 GLOBAL_EXTERN spinlock_t		cifs_tcp_ses_lock;
 
-#ifdef CONFIG_CIFS_DNOTIFY_EXPERIMENTAL /* unused temporarily */
-/* Outstanding dir notify requests */
-GLOBAL_EXTERN struct list_head GlobalDnotifyReqList;
-/* DirNotify response queue */
-GLOBAL_EXTERN struct list_head GlobalDnotifyRsp_Q;
-#endif /* was needed for dnotify, and will be needed for inotify when VFS fix */
-
 /*
  * Global transaction id (XID) information
  */
@@ -1874,19 +1867,9 @@ extern unsigned int cifs_min_small;  /* min size of small buf pool */
 extern unsigned int cifs_max_pending; /* MAX requests at once to server*/
 extern bool disable_legacy_dialects;  /* forbid vers=1.0 and vers=2.0 mounts */
 
-GLOBAL_EXTERN struct rb_root uidtree;
-GLOBAL_EXTERN struct rb_root gidtree;
-GLOBAL_EXTERN spinlock_t siduidlock;
-GLOBAL_EXTERN spinlock_t sidgidlock;
-GLOBAL_EXTERN struct rb_root siduidtree;
-GLOBAL_EXTERN struct rb_root sidgidtree;
-GLOBAL_EXTERN spinlock_t uidsidlock;
-GLOBAL_EXTERN spinlock_t gidsidlock;
-
 void cifs_oplock_break(struct work_struct *work);
 void cifs_queue_oplock_break(struct cifsFileInfo *cfile);
 
-extern const struct slow_work_ops cifs_oplock_break_ops;
 extern struct workqueue_struct *cifsiod_wq;
 extern struct workqueue_struct *decrypt_wq;
 extern struct workqueue_struct *fileinfo_put_wq;

fs/cifs/cifsproto.h

@@ -358,11 +358,6 @@ extern int CIFSSMBSetFileDisposition(const unsigned int xid,
 				     struct cifs_tcon *tcon,
 				     bool delete_file, __u16 fid,
 				     __u32 pid_of_opener);
-#if 0
-extern int CIFSSMBSetAttrLegacy(unsigned int xid, struct cifs_tcon *tcon,
-			char *fileName, __u16 dos_attributes,
-			const struct nls_table *nls_codepage);
-#endif /* possibly unneeded function */
 extern int CIFSSMBSetEOF(const unsigned int xid, struct cifs_tcon *tcon,
 			 const char *file_name, __u64 size,
 			 struct cifs_sb_info *cifs_sb, bool set_allocation);
@@ -504,12 +499,6 @@ extern int generate_smb311signingkey(struct cifs_ses *);
 extern int calc_lanman_hash(const char *password, const char *cryptkey,
 				bool encrypt, char *lnm_session_key);
 #endif /* CIFS_WEAK_PW_HASH */
-#ifdef CONFIG_CIFS_DNOTIFY_EXPERIMENTAL /* unused temporarily */
-extern int CIFSSMBNotify(const unsigned int xid, struct cifs_tcon *tcon,
-			const int notify_subdirs, const __u16 netfid,
-			__u32 filter, struct file *file, int multishot,
-			const struct nls_table *nls_codepage);
-#endif /* was needed for dnotify, and will be needed for inotify when VFS fix */
 extern int CIFSSMBCopy(unsigned int xid,
 			struct cifs_tcon *source_tcon,
 			const char *fromName,

fs/cifs/cifssmb.c

@@ -5917,56 +5917,6 @@ CIFSSMBSetPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 	return rc;
 }
 
-/* Can not be used to set time stamps yet (due to old DOS time format) */
-/* Can be used to set attributes */
-#if 0  /* Possibly not needed - since it turns out that strangely NT4 has a bug
-	  handling it anyway and NT4 was what we thought it would be needed for
-	  Do not delete it until we prove whether needed for Win9x though */
-int
-CIFSSMBSetAttrLegacy(unsigned int xid, struct cifs_tcon *tcon, char *fileName,
-		__u16 dos_attrs, const struct nls_table *nls_codepage)
-{
-	SETATTR_REQ *pSMB = NULL;
-	SETATTR_RSP *pSMBr = NULL;
-	int rc = 0;
-	int bytes_returned;
-	int name_len;
-
-	cifs_dbg(FYI, "In SetAttrLegacy\n");
-
-SetAttrLgcyRetry:
-	rc = smb_init(SMB_COM_SETATTR, 8, tcon, (void **) &pSMB,
-		      (void **) &pSMBr);
-	if (rc)
-		return rc;
-
-	if (pSMB->hdr.Flags2 & SMBFLG2_UNICODE) {
-		name_len =
-			ConvertToUTF16((__le16 *) pSMB->fileName, fileName,
-				       PATH_MAX, nls_codepage);
-		name_len++;     /* trailing null */
-		name_len *= 2;
-	} else {
-		name_len = copy_path_name(pSMB->fileName, fileName);
-	}
-	pSMB->attr = cpu_to_le16(dos_attrs);
-	pSMB->BufferFormat = 0x04;
-	inc_rfc1001_len(pSMB, name_len + 1);
-	pSMB->ByteCount = cpu_to_le16(name_len + 1);
-	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
-			 (struct smb_hdr *) pSMBr, &bytes_returned, 0);
-	if (rc)
-		cifs_dbg(FYI, "Error in LegacySetAttr = %d\n", rc);
-
-	cifs_buf_release(pSMB);
-
-	if (rc == -EAGAIN)
-		goto SetAttrLgcyRetry;
-
-	return rc;
-}
-#endif /* temporarily unneeded SetAttr legacy function */
-
 static void
 cifs_fill_unix_set_info(FILE_UNIX_BASIC_INFO *data_offset,
 			const struct cifs_unix_set_info_args *args)

fs/cifs/inode.c

@@ -2961,12 +2961,3 @@ cifs_setattr(struct user_namespace *mnt_userns, struct dentry *direntry,
 	/* BB: add cifs_setattr_legacy for really old servers */
 	return rc;
 }
-
-#if 0
-void cifs_delete_inode(struct inode *inode)
-{
-	cifs_dbg(FYI, "In cifs_delete_inode, inode = 0x%p\n", inode);
-	/* may have to add back in if and when safe distributed caching of
-	   directories added e.g. via FindNotify */
-}
-#endif