[linux-cifs-client] [PATCH] CIFS: Convert semaphore sesSem into a mutex

[Matthias Kaehlcke]

CIFS: The semaphore sesSem is used as a mutex, convert it to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias at kaehlcke.net>
---
 fs/cifs/cifsglob.h |    8 ++++++--
 fs/cifs/cifssmb.c  |   12 ++++++------
 fs/cifs/connect.c  |   10 +++++-----
 fs/cifs/misc.c     |    2 +-
 4 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 4b35f7e..f6ed65c 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -18,6 +18,7 @@
  */
 #include <linux/in.h>
 #include <linux/in6.h>
+#include <linux/mutex.h>
 #include <linux/slow-work.h>
 #include "cifs_fs_sb.h"
 #include "cifsacl.h"
@@ -204,7 +205,7 @@ struct cifsUidInfo {
 struct cifsSesInfo {
 	struct list_head smb_ses_list;
 	struct list_head tcon_list;
-	struct semaphore sesSem;
+	struct mutex ses_lock;
 #if 0
 	struct cifsUidInfo *uidInfo;	/* pointer to user info */
 #endif
@@ -633,9 +634,12 @@ require use of the stronger protocol */
  *  f_owner.lock protects certain per file struct operations
  *  mapping->page_lock protects certain per page operations
  *
+ *  Mutexes
+ *  -------
+ *  ses_lock     operations on smb session
+ *
  *  Semaphores
  *  ----------
- *  sesSem     operations on smb session
  *  tconSem    operations on tree connection
  *  fh_sem      file handle reconnection operations
  *
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 941441d..827f5f8 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -170,19 +170,19 @@ cifs_reconnect_tcon(struct cifsTconInfo *tcon, int smb_command)
 	 * need to prevent multiple threads trying to simultaneously
 	 * reconnect the same SMB session
 	 */
-	down(&ses->sesSem);
+	mutex_lock(&ses->ses_lock);
 	if (ses->need_reconnect)
 		rc = cifs_setup_session(0, ses, nls_codepage);
 
 	/* do we need to reconnect tcon? */
 	if (rc || !tcon->need_reconnect) {
-		up(&ses->sesSem);
+		mutex_unlock(&ses->ses_lock);
 		goto out;
 	}
 
 	mark_open_files_invalid(tcon);
 	rc = CIFSTCon(0, ses, tcon->treeName, tcon, nls_codepage);
-	up(&ses->sesSem);
+	mutex_unlock(&ses->ses_lock);
 	cFYI(1, ("reconnect tcon rc = %d", rc));
 
 	if (rc)
@@ -700,13 +700,13 @@ CIFSSMBLogoff(const int xid, struct cifsSesInfo *ses)
 	if (!ses || !ses->server)
 		return -EIO;
 
-	down(&ses->sesSem);
+	mutex_lock(&ses->ses_lock);
 	if (ses->need_reconnect)
 		goto session_already_dead; /* no need to send SMBlogoff if uid
 					      already closed due to reconnect */
 	rc = small_smb_init(SMB_COM_LOGOFF_ANDX, 2, NULL, (void **)&pSMB);
 	if (rc) {
-		up(&ses->sesSem);
+		mutex_unlock(&ses->ses_lock);
 		return rc;
 	}
 
@@ -721,7 +721,7 @@ CIFSSMBLogoff(const int xid, struct cifsSesInfo *ses)
 	pSMB->AndXCommand = 0xFF;
 	rc = SendReceiveNoRsp(xid, ses, (struct smb_hdr *) pSMB, 0);
 session_already_dead:
-	up(&ses->sesSem);
+	mutex_unlock(&ses->ses_lock);
 
 	/* if session dead then we do not need to do ulogoff,
 		since server closed smb session, no sense reporting
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 31bfa49..6e6065e 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2344,13 +2344,13 @@ try_mount_again:
 		 */
 		cifs_put_tcp_session(srvTcp);
 
-		down(&pSesInfo->sesSem);
+		mutex_lock(&pSesInfo->ses_lock);
 		if (pSesInfo->need_reconnect) {
 			cFYI(1, ("Session needs reconnect"));
 			rc = cifs_setup_session(xid, pSesInfo,
 						cifs_sb->local_nls);
 		}
-		up(&pSesInfo->sesSem);
+		mutex_unlock(&pSesInfo->ses_lock);
 	} else if (!rc) {
 		cFYI(1, ("Existing smb sess not found"));
 		pSesInfo = sesInfoAlloc();
@@ -2393,12 +2393,12 @@ try_mount_again:
 		}
 		pSesInfo->linux_uid = volume_info->linux_uid;
 		pSesInfo->overrideSecFlg = volume_info->secFlg;
-		down(&pSesInfo->sesSem);
+		mutex_lock(&pSesInfo->ses_lock);
 
 		/* BB FIXME need to pass vol->secFlgs BB */
 		rc = cifs_setup_session(xid, pSesInfo,
 					cifs_sb->local_nls);
-		up(&pSesInfo->sesSem);
+		mutex_unlock(&pSesInfo->ses_lock);
 	}
 
 	/* search for existing tcon to this server share */
@@ -2436,7 +2436,7 @@ try_mount_again:
 				rc = -ENODEV;
 				goto mount_fail_check;
 			} else {
-				/* BB Do we need to wrap sesSem around
+				/* BB Do we need to wrap ses_lock around
 				 * this TCon call and Unix SetFS as
 				 * we do on SessSetup and reconnect? */
 				rc = CIFSTCon(xid, pSesInfo, volume_info->UNC,
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index d27d4ec..679b82a 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -79,7 +79,7 @@ sesInfoAlloc(void)
 		++ret_buf->ses_count;
 		INIT_LIST_HEAD(&ret_buf->smb_ses_list);
 		INIT_LIST_HEAD(&ret_buf->tcon_list);
-		init_MUTEX(&ret_buf->sesSem);
+		mutex_init(&ret_buf->ses_lock);
 	}
 	return ret_buf;
 }
-- 
1.6.5