added magic to change loopback filesystem

2 files changed, 41 insertions, 6 deletions

diff --git a/isys/isys.c b/isys/isys.c
index 3af649d0a..59798f12f 100644
--- a/isys/isys.c
+++ b/isys/isys.c
@@ -39,7 +39,7 @@
 long long llseek(int fd, long long offset, int whence);
 
 /* FIXME: this is such a hack -- moduleInfoList ought to be a proper object */
-moduleInfoSet modInfoList;
+moduleInfoSet modInfoList = NULL;
 
 static PyObject * doFindModInfo(PyObject * s, PyObject * args);
 static PyObject * doGetOpt(PyObject * s, PyObject * args);
@@ -62,6 +62,7 @@ static PyObject * doPoptParse(PyObject * s, PyObject * args);
 static PyObject * doFbconProbe(PyObject * s, PyObject * args);
 static PyObject * doLoSetup(PyObject * s, PyObject * args);
 static PyObject * doUnLoSetup(PyObject * s, PyObject * args);
+static PyObject * doLoChangeFd(PyObject * s, PyObject * args);
 static PyObject * doDdFile(PyObject * s, PyObject * args);
 static PyObject * doGetRaidSuperblock(PyObject * s, PyObject * args);
 static PyObject * doDevSpaceFree(PyObject * s, PyObject * args);
@@ -85,6 +86,7 @@ static PyMethodDef isysModuleMethods[] = {
     { "raidstop", (PyCFunction) doRaidStop, METH_VARARGS, NULL },
     { "raidstart", (PyCFunction) doRaidStart, METH_VARARGS, NULL },
     { "getraidsb", (PyCFunction) doGetRaidSuperblock, METH_VARARGS, NULL },
+    { "lochangefd", (PyCFunction) doLoChangeFd, METH_VARARGS, NULL },
     { "losetup", (PyCFunction) doLoSetup, METH_VARARGS, NULL },
     { "unlosetup", (PyCFunction) doUnLoSetup, METH_VARARGS, NULL },
     { "ddfile", (PyCFunction) doDdFile, METH_VARARGS, NULL },
@@ -230,6 +232,9 @@ static PyObject * getModuleList(PyObject * s, PyObject * args) {
 	return NULL;
     }
 
+    if (!modInfoList)
+	modInfoList = isysNewModuleInfoSet();
+
     modules = isysGetModuleList(modInfoList, major);
     if (!modules) {
 	Py_INCREF(Py_None);
@@ -352,6 +357,21 @@ static PyObject * doUnLoSetup(PyObject * s, PyObject * args) {
     return Py_None;
 }
 
+static PyObject * doLoChangeFd(PyObject * s, PyObject * args) {
+    int loopfd;
+    int targfd;
+
+    if (!PyArg_ParseTuple(args, "ii", &loopfd, &targfd)) 
+	return NULL;
+    if (ioctl(loopfd, LOOP_CHANGE_FD, targfd)) {
+	PyErr_SetFromErrno(PyExc_SystemError);
+	return NULL;
+    }
+
+    Py_INCREF(Py_None);
+    return Py_None;
+}
+
 static PyObject * doLoSetup(PyObject * s, PyObject * args) {
     int loopfd;
     int targfd;
@@ -383,6 +403,9 @@ static PyObject * doFindModInfo(PyObject * s, PyObject * args) {
 
     if (!PyArg_ParseTuple(args, "s", &mod)) return NULL;
 
+    if (!modInfoList)
+	modInfoList = isysNewModuleInfoSet();
+
     mi = isysFindModuleInfo(modInfoList, mod);
     if (!mi) {
 	Py_INCREF(Py_None);
@@ -541,6 +564,9 @@ static PyObject * doReadModInfo(PyObject * s, PyObject * args) {
 
     if (!PyArg_ParseTuple(args, "s", &fn)) return NULL;
 
+    if (!modInfoList)
+	modInfoList = isysNewModuleInfoSet();
+
     if (isysReadModuleInfo(fn, modInfoList, MI_LOCATION_NONE, NULL)) {
 	PyErr_SetFromErrno(PyExc_IOError);
 	return NULL;
@@ -714,8 +740,6 @@ static PyObject * smpAvailable(PyObject * s, PyObject * args) {
 }
 
 void init_isys(void) {
-    modInfoList = isysNewModuleInfoSet();
-
     Py_InitModule("_isys", isysModuleMethods);
 }
 
diff --git a/isys/isys.py b/isys/isys.py
index d810b9139..56fa8a649 100644
--- a/isys/isys.py
+++ b/isys/isys.py
@@ -35,13 +35,24 @@ def raidsb(mdDevice):
     os.close(fd)
     return rc
 
-def losetup(device, file):
-    loop = os.open(device, os.O_RDONLY)
-    targ = os.open(file, os.O_RDWR)
+def losetup(device, file, readonly = 0):
+    if readonly:
+	mode = os.O_RDONLY
+    else:
+	mode = os.O_RDWR
+    targ = os.open(file, mode)
+    loop = os.open(device, mode)
     _isys.losetup(loop, targ, file)
     os.close(loop)
     os.close(targ)
 
+def lochangefd(device, file):
+    loop = os.open(device, os.O_RDONLY)
+    targ = os.open(file, os.O_RDONLY)
+    _isys.lochangefd(loop, targ)
+    os.close(loop)
+    os.close(targ)
+
 def unlosetup(device):
     loop = os.open(device, os.O_RDONLY)
     _isys.unlosetup(loop)