Virtual File System module load and unload

Change-Id: Iaa6a256a8a15ac48bfba5bc1cab292c5ac246166
Reviewed-on: http://gfw160.austin.ibm.com:8080/gerrit/253
Tested-by: Jenkins Server
Reviewed-by: A. Patrick Williams III <iawillia@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

3 files changed, 415 insertions, 0 deletions

diff --git a/src/usr/vfs/makefile b/src/usr/vfs/makefile
new file mode 100644
index 000000000..2212d9d4f
--- /dev/null
+++ b/src/usr/vfs/makefile
@@ -0,0 +1,8 @@
+ROOTPATH = ../../..
+MODULE = vfs
+
+OBJS = vfsrp.o
+
+#SUBDIRS = test.d
+
+include ${ROOTPATH}/config.mk
diff --git a/src/usr/vfs/vfsrp.C b/src/usr/vfs/vfsrp.C
new file mode 100644
index 000000000..04e90ecc0
--- /dev/null
+++ b/src/usr/vfs/vfsrp.C
@@ -0,0 +1,317 @@
+/**
+ * @file vfsrp.C 
+ * @brief Virtual File system Extended image support
+ */
+
+#include <limits.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/msg.h>
+#include <sys/vfs.h>
+#include <vfs/vfs.H>
+#include <vfs/vfs_reasoncodes.H>
+#include <sys/task.h>
+#include <sys/mm.h>
+#include <initservice/taskargs.H>
+#include <trace/interface.H>
+#include "vfsrp.H"
+#include <pnor/pnorif.H>
+#include <util/align.H>
+
+using namespace VFS;
+
+// Trace definitions
+trace_desc_t * g_trac_vfs = NULL;
+TRAC_INIT(&g_trac_vfs, VFS_COMP_NAME, 1024);
+
+/**
+ * setup _start and handle barrier
+ */
+TASK_ENTRY_MACRO( VfsRp::init );
+
+// ----------------------------------------------------------------------------
+
+VfsRp::~VfsRp()
+{
+    // Unloading of this module currently not supported.
+    // unregister msg queue?  Currently can't do that
+    // msg_q_destroy(iv_msgQ);
+}
+
+// ----------------------------------------------------------------------------
+
+/**
+ * STATIC initializer of vfs resource provider entry point
+ */
+void VfsRp::init( void * i_taskArgs )
+{
+    errlHndl_t err = NULL;
+    err = Singleton<VfsRp>::instance()._init();
+    INITSERVICE::TaskArgs::TaskArgs* args = (INITSERVICE::TaskArgs::TaskArgs*)i_taskArgs;
+    if(err) 
+    {
+        args->postErrorLog(err);
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+/**
+ * Helper function to start vfs messge handler
+ */
+void VfsRp::msg_handler(void * unused)
+{
+    Singleton<VfsRp>::instance().msgHandler();
+}
+
+// ----------------------------------------------------------------------------
+
+void VfsRp::load_unload(void * i_msg)
+{
+    Singleton<VfsRp>::instance()._load_unload((msg_t*)i_msg);
+    task_end();
+}
+
+// ----------------------------------------------------------------------------
+
+void VfsRp::exec(void * i_msg)
+{
+    Singleton<VfsRp>::instance()._exec((msg_t*)i_msg);
+    task_end();
+}
+
+// ----------------------------------------------------------------------------
+
+/**
+ * Initialze the vfs resource provider
+ */
+errlHndl_t VfsRp::_init()
+{
+    errlHndl_t err = NULL;
+    size_t rc = 0;
+    iv_msgQ = msg_q_create();
+    rc = msg_q_register(iv_msgQ, VFS_MSG);
+
+    // Discover PNOR virtual address of extended image
+    PNOR::SectionInfo_t l_pnor_info;
+
+    // How will SIDE eventually be determined? TODO
+    err = PNOR::getSectionInfo(PNOR::HB_EXT_CODE, PNOR::SIDE_A, l_pnor_info);
+    if(!err)
+    {
+        iv_pnor_vaddr = l_pnor_info.vaddr;
+
+        rc = mm_alloc_block
+            (iv_msgQ,
+             (void *)VFS_EXTENDED_MODULE_VADDR,
+             ALIGN_PAGE(l_pnor_info.size)
+            );
+        if(rc == 0)
+        {
+            // Start msg_handler
+            //  NOTE: This would be a weak consistancy issues if
+            //  task_create were not a system call.
+            task_create(VfsRp::msg_handler, NULL);
+        }
+        else
+        {
+            err = new ERRORLOG::ErrlEntry
+                (
+                 ERRORLOG::ERRL_SEV_CRITICAL_SYS_TERM,   //  severity
+                 VFS::VFS_MODULE_ID,                     //  moduleid
+                 VFS::VFS_ALLOC_VMEM_FAILED,             //  reason Code
+                 rc,                                     //  user1 = rc
+                 0                                       //  user2
+                );
+        }
+    }
+
+    return err;
+}
+
+
+// ----------------------------------------------------------------------------
+
+void VfsRp::msgHandler()
+{
+    while(1)
+    {
+        msg_t* msg = msg_wait(iv_msgQ);
+
+        switch(msg->type)
+        {
+            case VFS_MSG_LOAD:
+                {
+                    TRACDBIN(g_trac_vfs, "INFO: load module ",
+                             (const char *) msg->data[0],
+                             strlen((const char *) msg->data[0]));
+
+                    // run in own task so page faults can be handled
+                    task_create(load_unload, msg);
+                }
+                break;
+
+            case VFS_MSG_UNLOAD:
+                {
+                    TRACDBIN(g_trac_vfs, "INFO: unload module ",
+                             (const char *) msg->data[0],
+                             strlen((const char *) msg->data[0]));
+
+                    // run in own task so page faults can be handled
+                    task_create(load_unload, msg);
+
+                }
+                break;
+
+            case VFS_MSG_EXEC:
+                {
+                    msg_t * msg1 = (msg_t *) msg->data[0];
+                    TRACDCOMP(g_trac_vfs, "VFS: Got exec request of %s",
+                           (const char*)msg1->data[0]);
+
+                    // run in own task so page faults can be handled
+                    task_create(exec, msg);
+
+                }
+                break;
+
+            case MSG_MM_RP_READ:
+                {
+                    uint64_t vaddr = msg->data[0];
+                    uint64_t paddr = msg->data[1]; //page aligned
+
+                    vaddr -= vaddr % PAGE_SIZE;
+                    vaddr -= VFS_EXTENDED_MODULE_VADDR;
+                    memcpy((void *)paddr, (void *)(iv_pnor_vaddr+vaddr),
+                           PAGE_SIZE);
+
+                    mm_icache_invalidate((void*)paddr,PAGE_SIZE/8);
+
+                }
+                msg->data[1] = 0;
+                msg_respond(iv_msgQ, msg);
+                break;
+
+            case MSG_MM_RP_WRITE:
+                assert(0);              // not supported now
+                //msg->data[1] = 0;
+                //msg_respond(iv_msgQ, msg);
+                break;
+
+            case MSG_MM_RP_PERM:
+                msg->data[1] = -EINVAL;
+                msg_respond(iv_msgQ, msg);
+                break;
+
+            default:
+                msg_free(msg);
+                break;
+        }
+    } // while(1)
+}
+
+// ----------------------------------------------------------------------------
+
+void VfsRp::_load_unload(msg_t * i_msg)
+{
+    errlHndl_t err = NULL;
+    // Find VfsSystemModule
+    //  The TOC for the extended image sits at the start of the image and is
+    //  not location dependant, so just use the one pointed to by iv_pnor_vaddr
+    //  to avoid having to copy it to this block
+    VfsSystemModule * module =
+        vfs_find_module
+        (
+         (VfsSystemModule *)iv_pnor_vaddr, //VFS_EXTENDED_MODULE_TABLE_ADDRESS,
+         (const char *) i_msg->data[0]
+        );
+
+    if(module)
+    {
+        // TODO mark text page(s) as ro/executable
+        // TODO mark data page(s) as rw
+        if(i_msg->type == VFS_MSG_LOAD)
+        {
+            if(module->init)
+            {
+                (module->init)(NULL);
+            }
+        }
+        else // unload
+        {
+            if(module->fini)
+            {
+                (module->fini)(NULL);
+            }
+
+            // TODO mark pages as no access
+        }
+    }
+    else
+    {
+        // TODO  error log? for now it's probably in the base
+        //       and is aready loaded and initialized.
+        TRACFBIN(g_trac_vfs, ERR_MRK"Module not found: ",
+                 (const char *) i_msg->data[0],
+                 strlen((const char *) i_msg->data[0]) );
+    }
+    i_msg->data[0] = (uint64_t) err;
+    msg_respond(iv_msgQ, i_msg);
+}
+
+// ----------------------------------------------------------------------------
+
+void VfsRp::_exec(msg_t * i_msg)
+{
+    msg_t * msg1 = (msg_t *) i_msg->data[0];
+
+    //  The TOC for the extended image sits at the start of the image and is
+    //  not location dependant, so just use the one pointed to by iv_pnor_vaddr
+    //  to avoid having to copy it to this block
+    VfsSystemModule * module = 
+        vfs_find_module((VfsSystemModule *)(iv_pnor_vaddr +
+                                            VFS_EXTENDED_MODULE_TABLE_OFFSET),
+                        (const char*) msg1->data[0]);
+
+    tid_t child = vfs_exec(module, (void*) msg1->data[1]);
+
+    msg_q_t vfsRmsgQ = (msg_q_t) i_msg->data[1];
+
+    msg1->data[0] = child;
+
+    msg_respond(vfsRmsgQ,msg1);
+    msg_free(i_msg);
+}
+
+
+// -- External interface ------------------------------------------------------
+
+errlHndl_t VFS::module_load_unload(const char * i_module, VfsMessages i_msgtype)
+{
+    errlHndl_t err = NULL;
+    msg_q_t vfsQ = msg_q_resolve(VFS_MSG);
+    msg_t* msg = msg_allocate();
+    msg->type = i_msgtype;
+    msg->data[0] = (uint64_t) i_module;
+    int rc = msg_sendrecv(vfsQ, msg);
+
+    if (0 == rc)
+    {
+        err = (errlHndl_t) msg->data[0];
+    }
+    else
+    {
+        err = new ERRORLOG::ErrlEntry
+            (
+             ERRORLOG::ERRL_SEV_CRITICAL_SYS_TERM,   //  severity
+             VFS::VFS_MODULE_ID,                     //  moduleid
+             VFS::VFS_LOAD_FAILED,                   //  reason Code
+             rc,                                     //  user1 = msg_sendrecv rc
+             i_msgtype                               //  user2 = message type
+            );
+    }
+
+    msg_free(msg);
+    return err;
+}
+
diff --git a/src/usr/vfs/vfsrp.H b/src/usr/vfs/vfsrp.H
new file mode 100644
index 000000000..456979e2d
--- /dev/null
+++ b/src/usr/vfs/vfsrp.H
@@ -0,0 +1,90 @@
+#ifndef VFSRP_H
+#define VFSRP_H
+
+#include <stdint.h>
+#include <builtins.h>
+#include <errl/errltypes.H>
+
+struct msg_t;
+
+namespace VFS
+{
+    void vfs_msg_handler(void * unused);
+
+    /**
+     * Virtual File System Service
+     */
+    class VfsRp
+    {
+        public:
+
+            /**
+             * static init
+             * @param[in] task args
+             */
+            static void init(void * i_taskArgs);
+
+        protected:
+            /**
+             * Ctor
+             */
+            VfsRp() : iv_msgQ(NULL), iv_pnor_vaddr(0) {}
+
+            /**
+             * Dtor
+             */
+            ~VfsRp();
+
+            /**
+             * Start message handler
+             */
+            static void msg_handler(void * unused);
+
+            /**
+             * Load or Unload a module
+             * @param[in] i_msg the message
+             * @note Does not return. calls task_end()
+             */
+            static void load_unload(void * i_msg);
+
+            /**
+             * Call _start on module
+             * @param[in] i_msg the message
+             * @note Does not return. calls task_end()
+             */
+            static void exec(void * i_msg);
+
+        private: // functions
+
+            /**
+             * Initialize this object
+             * @return return code on error
+             */
+            errlHndl_t _init();
+
+            /**
+             * Message handler 
+             */
+            void msgHandler();
+
+            /**
+             * Load or Unload a module
+             * @param[in] i_msg the message
+             */
+            void _load_unload(msg_t * i_msg);
+
+            /**
+             * Call _start on module
+             * @param[in] i_msg the message
+             */
+            void _exec(msg_t * i_msg);
+
+        private: // data
+
+            msg_q_t iv_msgQ;         //!< message queue
+            uint64_t iv_pnor_vaddr;  //!< virtual address of ext image in PFNOR
+    };
+
+}; // VFS namepsace
+
+#endif