Fix problem caused by void ptr and clean up code paths
[yaffs2.git] / direct / yaffsfs.c
index f0e1f45b3b781c27ab1ab6291d6dd5ff94f19498..7e2fc39908df33f1903be17c45333a89fac3a8f4 100644 (file)
 #include "yaffsfs.h"
 #include "yaffs_guts.h"
 #include "yaffscfg.h"
-#include <string.h> // for memset
 #include "yportenv.h"
+#include "yaffs_trace.h"
+
+#include <string.h> // for memset
 
 #define YAFFSFS_MAX_SYMLINK_DEREFERENCES 5
 
 #endif
 
 
-const char *yaffsfs_c_version="$Id: yaffsfs.c,v 1.28 2009-10-19 23:42:55 charles Exp $";
+/* YAFFSFS_RW_SIZE must be a power of 2 */
+#define YAFFSFS_RW_SHIFT (13)
+#define YAFFSFS_RW_SIZE  (1<<YAFFSFS_RW_SHIFT)
+
+
+const char *yaffsfs_c_version="$Id: yaffsfs.c,v 1.35 2010-02-25 22:38:03 charles Exp $";
 
 // configurationList is the list of devices that are supported
 static yaffsfs_DeviceConfiguration *yaffsfs_configurationList;
@@ -41,16 +48,21 @@ static void yaffsfs_RemoveObjectCallback(yaffs_Object *obj);
 
 unsigned int yaffs_wr_attempts;
 
+typedef struct {
+       int count;
+       yaffs_Object *iObj;
+} yaffsfs_Inode;
+
 typedef struct{
-       __u8  inUse:1;          // this handle is in use
-       __u8  readOnly:1;       // this handle is read only
-       __u8  append:1;         // append only
-       __u8  exclusive:1;      // exclusive
+       __u8    readOnly:1;     // this handle is read only
+       __u8    append:1;       // append only
+       __u8    exclusive:1;    // exclusive
+       int     inodeId:13;     // the object
+       int     useCount:16;    // Use count for this handle
        __u32 position;         // current position in file
-       yaffs_Object *obj;      // the object
 }yaffsfs_Handle;
 
-
+static yaffsfs_Inode yaffsfs_inode[YAFFSFS_N_HANDLES];
 static yaffsfs_Handle yaffsfs_handle[YAFFSFS_N_HANDLES];
 
 // yaffsfs_InitHandle
@@ -59,10 +71,11 @@ static yaffsfs_Handle yaffsfs_handle[YAFFSFS_N_HANDLES];
 static int yaffsfs_InitHandles(void)
 {
        int i;
-       for(i = 0; i < YAFFSFS_N_HANDLES; i++){
-               yaffsfs_handle[i].inUse = 0;
-               yaffsfs_handle[i].obj = NULL;
-       }
+       memset(yaffsfs_inode,0,sizeof(yaffsfs_inode));
+       memset(yaffsfs_handle,0,sizeof(yaffsfs_handle));
+       for(i = 0; i < YAFFSFS_N_HANDLES; i++)
+               yaffsfs_handle[i].inodeId = -1;
+
        return 0;
 }
 
@@ -74,22 +87,93 @@ yaffsfs_Handle *yaffsfs_GetHandlePointer(int h)
        return &yaffsfs_handle[h];
 }
 
-yaffs_Object *yaffsfs_GetHandleObject(int handle)
+yaffsfs_Inode *yaffsfs_GetInodePointer(int handle)
 {
        yaffsfs_Handle *h = yaffsfs_GetHandlePointer(handle);
 
-       if(h && h->inUse)
-               return h->obj;
+       if(h && h->useCount > 0 && h->inodeId >= 0 && h->inodeId < YAFFSFS_N_HANDLES)
+               return  &yaffsfs_inode[h->inodeId];
 
        return NULL;
 }
 
+yaffs_Object *yaffsfs_GetHandleObject(int handle)
+{
+       yaffsfs_Inode *in = yaffsfs_GetInodePointer(handle);
+
+       if(in)
+               return in->iObj;
+
+       return NULL;
+}
+
+//yaffsfs_GetInodeIdForObject
+// Grab an inode entry when opening a new inode.
+//
+
+static int yaffsfs_GetInodeIdForObject(yaffs_Object *obj)
+{
+       int i;
+       int ret = -1;
+       yaffsfs_Inode *in = NULL;
+       
+       if(obj)
+               obj = yaffs_GetEquivalentObject(obj);
+
+       /* Look for it. If we can't find it then make one */
+       for(i = 0; i < YAFFSFS_N_HANDLES && ret < 0; i++){
+               if(yaffsfs_inode[i].iObj == obj)
+                       ret = i;
+       }
+
+       for(i = 0; i < YAFFSFS_N_HANDLES && ret < 0; i++){
+               if(!yaffsfs_inode[i].iObj)
+                       ret = i;
+       }
+       
+       
+       if(ret>=0){
+               in = &yaffsfs_inode[ret];
+               if(!in->iObj)
+                       in->count = 0;
+               in->iObj = obj;
+               in->count++;
+       }
+       
+       
+       return ret;
+}
+
+static void yaffsfs_ReleaseInode(yaffsfs_Inode *in)
+{
+       yaffs_Object *obj;
+       
+       obj = in->iObj;
+
+       if(obj->unlinked)
+               yaffs_DeleteObject(obj);
+       
+       obj->myInode = NULL;
+       in->iObj = NULL;
+
+}
+
+static void yaffsfs_PutInode(int inodeId)
+{
+       if(inodeId >= 0 && inodeId < YAFFSFS_N_HANDLES){
+               yaffsfs_Inode *in = & yaffsfs_inode[inodeId];
+               in->count--;
+               if(in->count <= 0)
+                       yaffsfs_ReleaseInode(in);
+       }       
+}
+
 
 //yaffsfs_GetHandle
 // Grab a handle (when opening a file)
 //
 
-static int yaffsfs_GetHandle(void)
+static int yaffsfs_GetNewHandle(void)
 {
        int i;
        yaffsfs_Handle *h;
@@ -99,31 +183,51 @@ static int yaffsfs_GetHandle(void)
                if(!h){
                        // todo bug: should never happen
                }
-               if(!h->inUse){
+               if(h->useCount < 1){
                        memset(h,0,sizeof(yaffsfs_Handle));
-                       h->inUse=1;
+                       h->inodeId=-1;
+                       h->useCount=1;
                        return i;
                }
        }
        return -1;
 }
 
+// yaffs_GetHandle
+// Increase use of handle when reading/writing a file
+static int yaffsfs_GetHandle(int handle)
+{
+       yaffsfs_Handle *h = yaffsfs_GetHandlePointer(handle);
+
+       if(h && h->useCount > 0){       
+               h->useCount++;
+       }
+       return 0;
+}
+
 // yaffs_PutHandle
-// Let go of a handle (when closing a file)
+// Let go of a handle when closing a file or aborting an open or
+// ending a read or write.
 //
 static int yaffsfs_PutHandle(int handle)
 {
        yaffsfs_Handle *h = yaffsfs_GetHandlePointer(handle);
 
-       if(h){
-               h->inUse = 0;
-               h->obj = NULL;
+       if(h && h->useCount > 0){       
+               h->useCount--;
+               if(h->useCount < 1){
+                       if(h->inodeId >= 0){
+                               yaffsfs_PutInode(h->inodeId);
+                               h->inodeId = -1;
+                       }
+               }
        }
        return 0;
 }
 
 
 
+
 // Stuff to search for a directory from a path
 
 
@@ -378,8 +482,8 @@ int yaffs_dup(int fd)
        yaffsfs_Lock();
 
        oldPtr = yaffsfs_GetHandlePointer(fd);
-       if(oldPtr && oldPtr->inUse)
-               newHandle = yaffsfs_GetHandle();
+       if(oldPtr && oldPtr->useCount > 0)
+               newHandle = yaffsfs_GetNewHandle();
        if(newHandle >= 0)
                newPtr = yaffsfs_GetHandlePointer(newHandle);
 
@@ -418,7 +522,7 @@ int yaffs_open(const YCHAR *path, int oflag, int mode)
 
        yaffsfs_Lock();
 
-       handle = yaffsfs_GetHandle();
+       handle = yaffsfs_GetNewHandle();
 
        if(handle >= 0){
 
@@ -431,6 +535,9 @@ int yaffs_open(const YCHAR *path, int oflag, int mode)
                if(obj && obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
                        obj = yaffsfs_FollowLink(obj,symDepth++);
 
+               if(obj)
+                       obj = yaffs_GetEquivalentObject(obj);
+
                if(obj && obj->variantType != YAFFS_OBJECT_TYPE_FILE)
                        obj = NULL;
 
@@ -439,10 +546,9 @@ int yaffs_open(const YCHAR *path, int oflag, int mode)
                        alreadyOpen = alreadyExclusive = 0;
 
                        for(i = 0; i < YAFFSFS_N_HANDLES; i++){
-
                                if(i != handle &&
-                                  yaffsfs_handle[i].inUse &&
-                                   obj == yaffsfs_handle[i].obj){
+                                  yaffsfs_handle[i].useCount > 0 &&
+                                   obj == yaffsfs_inode[yaffsfs_handle[i].inodeId].iObj){
                                        alreadyOpen = 1;
                                        if(yaffsfs_handle[i].exclusive)
                                                alreadyExclusive = 1;
@@ -475,7 +581,10 @@ int yaffs_open(const YCHAR *path, int oflag, int mode)
                } else if((oflag & O_CREAT)) {
                        // Let's see if we can create this file
                        dir = yaffsfs_FindDirectory(NULL,path,&name,0);
-                       if(dir)
+                       if(dir  && dir->myDev->readOnly){
+                               yaffsfs_SetError(-EINVAL);
+                               errorReported = 1;
+                       } else if(dir)
                                obj = yaffs_MknodFile(dir,name,mode,0,0);
                        else {
                                yaffsfs_SetError(-ENOTDIR);
@@ -484,14 +593,24 @@ int yaffs_open(const YCHAR *path, int oflag, int mode)
                }
 
                if(obj && !openDenied) {
-                       h->obj = obj;
-                       h->inUse = 1;
+                       int inodeId = yaffsfs_GetInodeIdForObject(obj);
+
+                       if(inodeId<0) {
+                               /*
+                                * Todo: Fix any problem if inodes run out, though that
+                                * can't happen if the number of inode items >= number of handles. 
+                                */
+                       }
+                       
+                       h->inodeId = inodeId;
                        h->readOnly = (oflag & (O_WRONLY | O_RDWR)) ? 0 : 1;
                        h->append =  (oflag & O_APPEND) ? 1 : 0;
                        h->exclusive = (oflag & O_EXCL) ? 1 : 0;
                        h->position = 0;
 
-                        obj->inUse++;
+                       /* Hook inode to object */
+                        obj->myInode = (void*) &yaffsfs_inode[inodeId];
+
                         if((oflag & O_TRUNC) && !h->readOnly)
                                 yaffs_ResizeFile(obj,0);
                } else {
@@ -518,9 +637,9 @@ int yaffs_Dofsync(int fd,int datasync)
 
        h = yaffsfs_GetHandlePointer(fd);
 
-       if(h && h->inUse)
+       if(h && h->useCount > 0)
                // flush the file
-               yaffs_FlushFile(h->obj,1,datasync);
+               yaffs_FlushFile(yaffsfs_inode[h->inodeId].iObj,1,datasync);
        else {
                // bad handle
                yaffsfs_SetError(-EBADF);
@@ -556,13 +675,9 @@ int yaffs_close(int fd)
 
        h = yaffsfs_GetHandlePointer(fd);
 
-       if(h && h->inUse) {
+       if(h && h->useCount > 0) {
                // clean up
-               yaffs_FlushFile(h->obj,1,0);
-               h->obj->inUse--;
-               if(h->obj->inUse <= 0 && h->obj->unlinked)
-                       yaffs_DeleteObject(h->obj);
-
+               yaffs_FlushFile(yaffsfs_inode[h->inodeId].iObj,1,0);
                yaffsfs_PutHandle(fd);
                retVal = 0;
        } else {
@@ -576,24 +691,36 @@ int yaffs_close(int fd)
        return retVal;
 }
 
-int yaffs_read(int fd, void *buf, unsigned int nbyte)
+
+
+int yaffsfs_do_read(int fd, void *vbuf, unsigned int nbyte, int isPread, int offset)
 {
        yaffsfs_Handle *h = NULL;
        yaffs_Object *obj = NULL;
        int pos = 0;
-       int nRead = -1;
+       int startPos = 0;
+       int nRead = 0;
+       int nToRead = 0;
+       int totalRead = 0;
        unsigned int maxRead;
+       __u8 *buf = (__u8 *)vbuf;
 
        yaffsfs_Lock();
        h = yaffsfs_GetHandlePointer(fd);
        obj = yaffsfs_GetHandleObject(fd);
 
-       if(!h || !obj)
+       if(!h || !obj){
                // bad handle
                yaffsfs_SetError(-EBADF);
+               totalRead = -1;
+       } else if( h && obj){
+               if(isPread)
+                       startPos = offset;
+               else
+                       startPos = h->position;
 
-       else if( h && obj){
-               pos=  h->position;
+               pos = startPos;
+                                       
                if(yaffs_GetObjectFileLength(obj) > pos)
                        maxRead = yaffs_GetObjectFileLength(obj) - pos;
                else
@@ -603,137 +730,146 @@ int yaffs_read(int fd, void *buf, unsigned int nbyte)
                        nbyte = maxRead;
 
 
-               if(nbyte > 0) {
-                       nRead = yaffs_ReadDataFromFile(obj,buf,pos,nbyte);
-                       if(nRead >= 0)
-                               h->position = pos + nRead;
-                       else {
-                               //todo error
-                       }
-               } else
-                       nRead = 0;
-
-       }
-
-       yaffsfs_Unlock();
-
-
-       return (nRead >= 0) ? nRead : -1;
+               yaffsfs_GetHandle(fd);
 
-}
+               while(nbyte > 0) {
+                       nToRead = YAFFSFS_RW_SIZE - (pos & (YAFFSFS_RW_SIZE -1));
+                       if(nToRead > nbyte)
+                               nToRead = nbyte;
+                       nRead = yaffs_ReadDataFromFile(obj,buf,pos,nToRead);
 
-int yaffs_pread(int fd, void *buf, unsigned int nbyte, unsigned int offset)
-{
-       yaffsfs_Handle *h = NULL;
-       yaffs_Object *obj = NULL;
-       int pos = 0;
-       int nRead = -1;
-       unsigned int maxRead;
+                       if(nRead > 0){
+                               totalRead += nRead;
+                               pos += nRead;
+                               buf += nRead;
+                       }
 
-       yaffsfs_Lock();
-       h = yaffsfs_GetHandlePointer(fd);
-       obj = yaffsfs_GetHandleObject(fd);
+                       if(nRead == nToRead)
+                               nbyte-=nRead;
+                       else
+                               nbyte = 0; /* no more to read */
+                                       
+                                       
+                       if(nbyte > 0){
+                               yaffsfs_Unlock();
+                               yaffsfs_Lock();
+                       }
 
-       if(!h || !obj)
-               // bad handle
-               yaffsfs_SetError(-EBADF);
-       else if( h && obj) {
-               pos= offset;
-               if(yaffs_GetObjectFileLength(obj) > pos)
-                       maxRead = yaffs_GetObjectFileLength(obj) - pos;
-               else
-                       maxRead = 0;
+               }
 
-               if(nbyte > maxRead)
-                       nbyte = maxRead;
+               yaffsfs_PutHandle(fd);
 
+               if(!isPread) {
+                       if(totalRead >= 0)
+                               h->position = startPos + totalRead;
+                       else {
+                                       //todo error
+                       }
+               }
 
-               if(nbyte > 0)
-                       nRead = yaffs_ReadDataFromFile(obj,buf,pos,nbyte);
-               else
-                       nRead = 0;
        }
 
        yaffsfs_Unlock();
 
+       return (totalRead >= 0) ? totalRead : -1;
 
-       return (nRead >= 0) ? nRead : -1;
+}
 
+int yaffs_read(int fd, void *buf, unsigned int nbyte)
+{
+       return yaffsfs_do_read(fd, buf, nbyte, 0, 0);
 }
 
-int yaffs_write(int fd, const void *buf, unsigned int nbyte)
+int yaffs_pread(int fd, void *buf, unsigned int nbyte, unsigned int offset)
+{
+       return yaffsfs_do_read(fd, buf, nbyte, 1, offset);
+}
+
+int yaffsfs_do_write(int fd, const void *vbuf, unsigned int nbyte, int isPwrite, int offset)
 {
        yaffsfs_Handle *h = NULL;
        yaffs_Object *obj = NULL;
        int pos = 0;
-       int nWritten = -1;
+       int startPos = 0;
+       int nWritten = 0;
+       int totalWritten = 0;
        int writeThrough = 0;
+       int nToWrite = 0;
+       const __u8 *buf = (const __u8 *)vbuf;
 
        yaffsfs_Lock();
        h = yaffsfs_GetHandlePointer(fd);
        obj = yaffsfs_GetHandleObject(fd);
 
-       if(!h || !obj)
+       if(!h || !obj){
                // bad handle
                yaffsfs_SetError(-EBADF);
-       else if( h && obj && h->readOnly){
-               // todo error
+               totalWritten = -1;
+       } else if( h && obj && (h->readOnly || obj->myDev->readOnly)){
+               yaffsfs_SetError(-EINVAL);
+               totalWritten=-1;
        } else if( h && obj){
+               if(isPwrite)
+                       startPos = offset;
                if(h->append)
-                       pos =  yaffs_GetObjectFileLength(obj);
+                       startPos = yaffs_GetObjectFileLength(obj);
                else
-                       pos = h->position;
+                       startPos = h->position;
+
+               yaffsfs_GetHandle(fd);
+               pos = startPos;
+               while(nbyte > 0) {
+                       nToWrite = YAFFSFS_RW_SIZE - (pos & (YAFFSFS_RW_SIZE -1));
+                       if(nToWrite > nbyte)
+                               nToWrite = nbyte;
+
+                       nWritten = yaffs_WriteDataToFile(obj,buf,pos,nToWrite,writeThrough);
+                       if(nWritten > 0){
+                               totalWritten += nWritten;
+                               pos += nWritten;
+                               buf += nWritten;
+                       }
 
-               nWritten = yaffs_WriteDataToFile(obj,buf,pos,nbyte,writeThrough);
+                       if(nWritten == nToWrite)
+                               nbyte -= nToWrite;
+                       else
+                               nbyte = 0;
 
-               if(nWritten >= 0)
-                       h->position = pos + nWritten;
-               else {
-                       //todo error
+                       if(nWritten < 1 && totalWritten < 1){
+                               yaffsfs_SetError(-ENOSPC);
+                               totalWritten = -1;
+                       }
+
+                       if(nbyte > 0){
+                               yaffsfs_Unlock();
+                               yaffsfs_Lock();
+                       }
                }
 
+               yaffsfs_PutHandle(fd);
+
+               if(!isPwrite){
+                       if(totalWritten > 0)
+                               h->position = startPos + totalWritten;
+                       else {
+                               //todo error
+                       }
+               }
        }
 
        yaffsfs_Unlock();
 
+       return (totalWritten >= 0) ? totalWritten : -1;
+}
 
-       return (nWritten >= 0) ? nWritten : -1;
-
+int yaffs_write(int fd, const void *buf, unsigned int nbyte)
+{
+       return yaffsfs_do_write(fd, buf, nbyte, 0, 0);
 }
 
 int yaffs_pwrite(int fd, const void *buf, unsigned int nbyte, unsigned int offset)
 {
-       yaffsfs_Handle *h = NULL;
-       yaffs_Object *obj = NULL;
-       int pos = 0;
-       int nWritten = -1;
-       int writeThrough = 0;
-
-       yaffsfs_Lock();
-       h = yaffsfs_GetHandlePointer(fd);
-       obj = yaffsfs_GetHandleObject(fd);
-
-       if(!h || !obj)
-               // bad handle
-               yaffsfs_SetError(-EBADF);
-       else if( h && obj && h->readOnly){
-               // todo error
-       }
-       else if( h && obj){
-               pos = offset;
-
-                nWritten = yaffs_WriteDataToFile(obj,buf,pos,nbyte,writeThrough);
-
-                if(nWritten < 0 || ((unsigned int)nWritten) < nbyte)
-                        yaffsfs_SetError(-ENOSPC);
-
-        }
-
-       yaffsfs_Unlock();
-
-
-       return (nWritten >= 0) ? nWritten : -1;
-
+       return yaffsfs_do_write(fd, buf, nbyte, 1, offset);
 }
 
 
@@ -752,6 +888,8 @@ int yaffs_truncate(const YCHAR *path,off_t newSize)
                yaffsfs_SetError(-ENOENT);
        else if(obj->variantType != YAFFS_OBJECT_TYPE_FILE)
                yaffsfs_SetError(-EISDIR);
+       else if(obj->myDev->readOnly)
+               yaffsfs_SetError(-EINVAL);
        else
                result = yaffs_ResizeFile(obj,newSize);
 
@@ -774,6 +912,8 @@ int yaffs_ftruncate(int fd, off_t newSize)
        if(!h || !obj)
                // bad handle
                yaffsfs_SetError(-EBADF);
+       else if(obj->myDev->readOnly)
+               yaffsfs_SetError(-EINVAL);
        else
                // resize the file
                result = yaffs_ResizeFile(obj,newSize);
@@ -840,6 +980,8 @@ int yaffsfs_DoUnlink(const YCHAR *path,int isDirectory)
                yaffsfs_SetError(-ENOTDIR);
        else if(!obj)
                yaffsfs_SetError(-ENOENT);
+       else if(obj->myDev->readOnly)
+               yaffsfs_SetError(-EINVAL);
        else if(!isDirectory && obj->variantType == YAFFS_OBJECT_TYPE_DIRECTORY)
                yaffsfs_SetError(-EISDIR);
        else if(isDirectory && obj->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
@@ -889,6 +1031,9 @@ int yaffs_rename(const YCHAR *oldPath, const YCHAR *newPath)
                // bad file
                yaffsfs_SetError(-EBADF);
                renameAllowed = 0;
+       } else if(obj->myDev->readOnly){
+               yaffsfs_SetError(-EINVAL);
+               renameAllowed = 0;
        } else if(olddir->myDev != newdir->myDev) {
                // oops must be on same device
                // todo error
@@ -927,7 +1072,7 @@ static int yaffsfs_DoStat(yaffs_Object *obj,struct yaffs_stat *buf)
                obj = yaffs_GetEquivalentObject(obj);
 
        if(obj && buf){
-               buf->st_dev = (int)obj->myDev->genericDevice;
+               buf->st_dev = (int)obj->myDev->context;
                buf->st_ino = obj->objectId;
                buf->st_mode = obj->yst_mode & ~S_IFMT; // clear out file type bits
 
@@ -1157,11 +1302,12 @@ int yaffs_chmod(const YCHAR *path, mode_t mode)
        yaffsfs_Lock();
        obj = yaffsfs_FindObject(NULL,path,0);
 
-       if(obj)
-               retVal = yaffsfs_DoChMod(obj,mode);
-       else
-               // todo error not found
+       if(!obj)
                yaffsfs_SetError(-ENOENT);
+       else if(obj->myDev->readOnly)
+               yaffsfs_SetError(-EINVAL);
+       else
+               retVal = yaffsfs_DoChMod(obj,mode);
 
        yaffsfs_Unlock();
 
@@ -1179,11 +1325,12 @@ int yaffs_fchmod(int fd, mode_t mode)
        yaffsfs_Lock();
        obj = yaffsfs_GetHandleObject(fd);
 
-       if(obj)
-               retVal = yaffsfs_DoChMod(obj,mode);
+       if(!obj)
+               yaffsfs_SetError(-ENOENT);
+       else if(obj->myDev->readOnly)
+               yaffsfs_SetError(-EINVAL);
        else
-               // bad handle
-               yaffsfs_SetError(-EBADF);
+               retVal = yaffsfs_DoChMod(obj,mode);
 
        yaffsfs_Unlock();
 
@@ -1200,18 +1347,22 @@ int yaffs_mkdir(const YCHAR *path, mode_t mode)
 
        yaffsfs_Lock();
        parent = yaffsfs_FindDirectory(NULL,path,&name,0);
-       if(parent)
-               dir = yaffs_MknodDirectory(parent,name,mode,0,0);
-       if(dir)
-               retVal = 0;
-       else {
-               if(!parent)
-                       yaffsfs_SetError(-ENOENT); // missing path
-               else if (yaffs_FindObjectByName(parent,name))
-                       yaffsfs_SetError(-EEXIST); // the name already exists
-               else
-                       yaffsfs_SetError(-ENOSPC); // just assume no space
-               retVal = -1;
+       if(parent && parent->myDev->readOnly){
+               yaffsfs_SetError(-EINVAL);
+       } else {
+               if(parent)
+                       dir = yaffs_MknodDirectory(parent,name,mode,0,0);
+               if(dir)
+                       retVal = 0;
+               else {
+                       if(!parent)
+                               yaffsfs_SetError(-ENOENT); // missing path
+                       else if (yaffs_FindObjectByName(parent,name))
+                               yaffsfs_SetError(-EEXIST); // the name already exists
+                       else
+                               yaffsfs_SetError(-ENOSPC); // just assume no space
+                       retVal = -1;
+               }
        }
 
        yaffsfs_Unlock();
@@ -1219,7 +1370,7 @@ int yaffs_mkdir(const YCHAR *path, mode_t mode)
        return retVal;
 }
 
-int yaffs_mount(const YCHAR *path)
+int yaffs_mount2(const YCHAR *path,int readOnly)
 {
        int retVal=-1;
        int result=YAFFS_FAIL;
@@ -1232,6 +1383,7 @@ int yaffs_mount(const YCHAR *path)
        dev = yaffsfs_FindDevice(path,&dummy);
        if(dev){
                if(!dev->isMounted){
+                       dev->readOnly = readOnly ? 1 : 0;
                        result = yaffs_GutsInitialise(dev);
                        if(result == YAFFS_FAIL)
                                // todo error - mount failed
@@ -1251,6 +1403,11 @@ int yaffs_mount(const YCHAR *path)
 
 }
 
+int yaffs_mount(const YCHAR *path)
+{
+       return yaffs_mount2(path,0);
+}
+
 int yaffs_sync(const YCHAR *path)
 {
         int retVal=-1;
@@ -1279,7 +1436,47 @@ int yaffs_sync(const YCHAR *path)
 }
 
 
-int yaffs_unmount(const YCHAR *path)
+int yaffs_remount(const YCHAR *path, int force, int readOnly)
+{
+        int retVal=-1;
+       yaffs_Device *dev=NULL;
+       YCHAR *dummy;
+
+       yaffsfs_Lock();
+       dev = yaffsfs_FindDevice(path,&dummy);
+       if(dev){
+               if(dev->isMounted){
+                       int i;
+                       int inUse;
+
+                       yaffs_FlushEntireDeviceCache(dev);
+
+                       for(i = inUse = 0; i < YAFFSFS_N_HANDLES && !inUse && !force; i++){
+                               if(yaffsfs_handle[i].useCount>0 && yaffsfs_inode[yaffsfs_handle[i].inodeId].iObj->myDev == dev)
+                                       inUse = 1; // the device is in use, can't unmount
+                       }
+
+                       if(!inUse || force){
+                               if(readOnly)
+                                       yaffs_CheckpointSave(dev);
+                               dev->readOnly =  readOnly ? 1 : 0;
+                               retVal = 0;
+                       } else
+                               yaffsfs_SetError(-EBUSY);
+
+               } else
+                       yaffsfs_SetError(-EINVAL);
+
+       }
+       else
+               yaffsfs_SetError(-ENODEV);
+
+       yaffsfs_Unlock();
+       return retVal;
+
+}
+
+int yaffs_unmount2(const YCHAR *path, int force)
 {
         int retVal=-1;
        yaffs_Device *dev=NULL;
@@ -1296,11 +1493,11 @@ int yaffs_unmount(const YCHAR *path)
                        yaffs_CheckpointSave(dev);
 
                        for(i = inUse = 0; i < YAFFSFS_N_HANDLES && !inUse; i++){
-                               if(yaffsfs_handle[i].inUse && yaffsfs_handle[i].obj->myDev == dev)
+                               if(yaffsfs_handle[i].useCount > 0 && yaffsfs_inode[yaffsfs_handle[i].inodeId].iObj->myDev == dev)
                                        inUse = 1; // the device is in use, can't unmount
                        }
 
-                       if(!inUse){
+                       if(!inUse || force){
                                yaffs_Deinitialise(dev);
 
                                retVal = 0;
@@ -1322,6 +1519,11 @@ int yaffs_unmount(const YCHAR *path)
 
 }
 
+int yaffs_unmount(const YCHAR *path)
+{
+       return yaffs_unmount2(path,0);
+}
+
 loff_t yaffs_freespace(const YCHAR *path)
 {
        loff_t retVal=-1;
@@ -1350,8 +1552,8 @@ loff_t yaffs_totalspace(const YCHAR *path)
        yaffsfs_Lock();
        dev = yaffsfs_FindDevice(path,&dummy);
        if(dev  && dev->isMounted){
-               retVal = (dev->endBlock - dev->startBlock + 1) - dev->nReservedBlocks;
-               retVal *= dev->nChunksPerBlock;
+               retVal = (dev->param.endBlock - dev->param.startBlock + 1) - dev->param.nReservedBlocks;
+               retVal *= dev->param.nChunksPerBlock;
                retVal *= dev->nDataBytesPerChunk;
 
        } else
@@ -1397,7 +1599,7 @@ void yaffs_initialise(yaffsfs_DeviceConfiguration *cfgList)
 
        while(cfg && cfg->prefix && cfg->dev){
                cfg->dev->isMounted = 0;
-               cfg->dev->removeObjectCallback = yaffsfs_RemoveObjectCallback;
+               cfg->dev->param.removeObjectCallback = yaffsfs_RemoveObjectCallback;
                cfg++;
        }
 
@@ -1544,7 +1746,7 @@ struct yaffs_dirent *yaffs_readdir(yaffs_DIR *dirp)
                        dsc->de.d_dont_use = (unsigned)dsc->nextReturn;
                        dsc->de.d_off = dsc->offset++;
                        yaffs_GetObjectName(dsc->nextReturn,dsc->de.d_name,NAME_MAX);
-                       if(yaffs_strlen(dsc->de.d_name) == 0)
+                       if(yaffs_strnlen(dsc->de.d_name,NAME_MAX+1) == 0)
                        {
                                // this should not happen!
                                yaffs_strcpy(dsc->de.d_name,_Y("zz"));
@@ -1601,7 +1803,9 @@ int yaffs_symlink(const YCHAR *oldpath, const YCHAR *newpath)
 
        yaffsfs_Lock();
        parent = yaffsfs_FindDirectory(NULL,newpath,&name,0);
-       if(parent){
+       if(parent && parent->myDev->readOnly)
+               yaffsfs_SetError(-EINVAL);
+       else if(parent){
                obj = yaffs_MknodSymLink(parent,name,mode,0,0,oldpath);
                if(obj)
                        retVal = 0;
@@ -1652,6 +1856,7 @@ int yaffs_link(const YCHAR *oldpath, const YCHAR *newpath)
        yaffs_Object *obj = NULL;
        yaffs_Object *target = NULL;
        int retVal = 0;
+       int newNameLength = 0;
 
 
        yaffsfs_Lock();
@@ -1662,6 +1867,9 @@ int yaffs_link(const YCHAR *oldpath, const YCHAR *newpath)
        if(!obj) {
                yaffsfs_SetError(-ENOENT);
                retVal = -1;
+       } else if(obj->myDev->readOnly){
+               yaffsfs_SetError(-EINVAL);
+               retVal= -1;
        } else if(target) {
                yaffsfs_SetError(-EEXIST);
                retVal = -1;
@@ -1680,8 +1888,18 @@ int yaffs_link(const YCHAR *oldpath, const YCHAR *newpath)
                        yaffsfs_SetError(-EXDEV);
                        retVal = -1;
                }
-
-               if(newdir && yaffs_strlen(newname) > 0) {
+               
+               newNameLength = yaffs_strnlen(newname,YAFFS_MAX_NAME_LENGTH+1);
+               
+               if(newNameLength == 0){
+                       yaffsfs_SetError(-ENOENT);
+                       retVal = -1;
+               } else if (newNameLength > YAFFS_MAX_NAME_LENGTH){
+                       yaffsfs_SetError(-ENAMETOOLONG);
+                       retVal = -1;
+               }
+               
+               if(retVal == 0) {
                        link = yaffs_Link(newdir,newname,obj);
                        if(link)
                                retVal = 0;