fix: 修复一些静态检查工具发现的问题

Signed-off-by: Far <yesiyuan2@huawei.com>
Change-Id: I2b93259d55a9eb1a9dfd5887fd7821c15274bb7f

fs/jffs2/src/vfs_jffs2.c

@@ -780,7 +780,6 @@ ssize_t VfsJffs2Readlink(struct Vnode *vnode, char *buffer, size_t bufLen)
 
     cnt = (bufLen - 1) < targetLen ? (bufLen - 1) : targetLen;
     if (LOS_CopyFromKernel(buffer, bufLen, (const char *)f->target, cnt) != 0) {
-        cnt = 0;
         LOS_MuxUnlock(&g_jffs2FsLock);
         return -EFAULT;
     }

fs/vfs/operation/vfs_force_umount.c

@@ -353,7 +353,7 @@ static struct file_operations_vfs g_errorFileOps = {
     .unlink = ErrorFopUnlink,
 };
 
-static struct Mount* GetDevMountPoint(struct Vnode *dev)
+static struct Mount* GetDevMountPoint(const struct Vnode *dev)
 {
     struct Mount *mnt = NULL;
     LIST_HEAD *mntList = GetMountList();
@@ -394,7 +394,7 @@ static void FilePreClose(struct file *filep, const struct file_operations_vfs *o
     }
 }
 
-static void FileDisableAndClean(struct Mount *mnt)
+static void FileDisableAndClean(const struct Mount *mnt)
 {
     struct filelist *flist = &tg_filelist;
     struct file *filep = NULL;
@@ -435,7 +435,7 @@ static void VnodeTryFree(struct Vnode *vnode)
     vnode->fop = &g_errorFileOps;
 }
 
-static void VnodeTryFreeAll(struct Mount *mount)
+static void VnodeTryFreeAll(const struct Mount *mount)
 {
     struct Vnode *vnode = NULL;
     struct Vnode *nextVnode = NULL;

fs/vfs/operation/vfs_writev.c

@@ -66,7 +66,6 @@ static int iov_trans_to_buf(char *buf, ssize_t totallen, const struct iovec *iov
             } else {
                 writepart = bytestowrite - ret;
                 curbuf += writepart;
-                totallen -= writepart;
                 break;
             }
         }