Changeset 8

Timestamp:

10/15/05 18:00:42 (6 years ago)

Author:

dkaplan1

Message:

Added worker thread per driver. Thread sleeps until it is needed

Files:

• arch/i386/kernel/callgate.c (modified) (5 diffs)
• arch/i386/kernel/entry.S (modified) (1 diff)
• arch/i386/kernel/process.c (modified) (3 diffs)
• arch/i386/kernel/traps.c (modified) (1 diff)
• include/asm-i386/processor.h (modified) (1 diff)
• include/linux/module.h (modified) (2 diffs)
• include/linux/sched.h (modified) (2 diffs)
• kernel/exit.c (modified) (2 diffs)
• kernel/fork.c (modified) (1 diff)
• kernel/module.c (modified) (5 diffs)
• .version (modified) (1 diff)

arch/i386/kernel/callgate.c

@@ -53 +53 @@
-void *ring2_driver_helper;
-
-
-void callgate_entry1(int oldcs, unsigned long param1);
-void callgate_entry2(int oldcs, unsigned long param1, unsigned long param2);
@@ -76 +75 @@
-        "pushl 16(%ebp)\n\t"
-        "decl %ecx\n\t"
-2
+3
-        "ja done2\n\t"
-        "call *callgate_table2(,%ecx,4)\n\t"
@@ -83 +82 @@
-        "leave\n\t"
-        "lret $8\n\t"
-
+, driver_exit
-);
-
@@ -161 +160 @@
-        "pushl %edx\n\t"
-        "call *%ebx\n\t"
-
-
-
+
+
+
+
+
+
-        "end_of_driver_thread_helper:\n\t"
-        "ud2\n"
@@ -181 +183 @@
-}
-
+//Cannot call from no context (ie interrupt handler)
+int calldriver(unsigned long addr, void *data, struct mm_struct *mm, unsigned long flags)
+{
+    struct task_struct *tsk;
+    struct pt_regs *regs;
+    if (in_interrupt())
+    {
+        printk(KERN_ERR "Cannot call driver code from interrupt handler\n");
+        return -1;
+    }
+/*
+    //try to find the stack!
+    stack=find_module_stack(addr);
+    if (!stack) {
+        printk(KERN_ERR "Could not find stack for code at address %x\n", (unsigned int) addr);
+        return -1;
+    }
+    pid=driver_thread(addr, data, stack, 0, ring);
+    tsk=find_task_by_pid(pid);
+    interruptible_sleep_on(&tsk->wait_kernexit);
+    return tsk->exit_code;*/
+
+    tsk=find_worker_thread(addr);
+    if (!tsk) {
+        printk(KERN_ERR "Could not find worker thread for address %x\n", addr);
+        return -1;
+    }
+    if (!tsk->available) {
+        printk(KERN_ERR "Thread busy...increase size of driver thread pool\n");
+        return -1;
+    }
+    tsk->available=0;
+    //Set memory map
+    if (mm)
+        tsk->mm=mm;
+
+    //Set new state for thread
+    //show_stack(tsk, NULL);
+    regs=task_pt_regs(tsk);
+    //show_regs(regs);
+    regs->ebx=addr;
+    regs->edx=(unsigned long) data;
+    if (tsk->ring == 1) {
+            regs->eip=(unsigned long) ring1_driver_helper;
+    } else if (tsk->ring == 2) {
+            regs->eip=(unsigned long) ring2_driver_helper;
+    } 
+    else
+        BUG();
+    
+    //printk("Going...\n");
+    //show_regs(regs);
+    wake_up_process(tsk);    
+
+    interruptible_sleep_on(&tsk->wait_driverfinish);
+    return tsk->exit_code;
+}
+
+    
+        
+    
+
+

arch/i386/kernel/entry.S

@@ -913 +913 @@
-        .long sys_ni_syscall            /* reserved for kexec */
-        .long sys_printdiag
+        .long driver_exit /* 285*/
-
-syscall_table_size=(.-sys_call_table)

arch/i386/kernel/process.c

@@ -346 +346 @@
-}
-*/
-driver_thread(unsigned long fn, void * arg, 
+create_driver_thread(
-{
-        struct pt_regs regs;
-
+
+
+
-        memset(&regs, 0, sizeof(regs));
-
-
+//
+//
-
-  if (!ring1_driver_helper)
@@ -362 +364 @@
-      regs.xcs = __RING1_CS;
-      regs.xss = __RING1_DS;
-
-stack_start=(unsigned char*)
+//
+orig_stack=
-  //    printk("Created ring 1 stack at %x", stack_start);
-  }
@@ -373 +375 @@
-      regs.xss = __RING2_DS;
-      regs.eip = (unsigned long) ring2_driver_helper;
-stack_start=(unsigned char*)
+orig_stack=
-    //  printk("Created ring 2 stack at %x", stack_start);
-  }
-  else
-      BUG();
-+=
+=(unsigned char*) orig_stack + 
-        regs.orig_eax = -1;
-  
-        regs.eflags = X86_EFLAGS_IF | X86_EFLAGS_SF | X86_EFLAGS_PF | 0x2;
-
-        /* Ok, create the new process.. */
-  //printk("Calling do_fork");
-
+
+
+
+
-}
-/*

arch/i386/kernel/traps.c

@@ -94 +94 @@
-asmlinkage void machine_check(void);
-
-
+
+
-
-static int valid_stack_ptr(struct task_struct *task, void *p)

include/asm-i386/processor.h

@@ -492 +492 @@
-
-/*Create driver thread in other ring*/
-
+
+
-
-extern unsigned long thread_saved_pc(struct task_struct *tsk);

include/linux/module.h

@@ -48 +48 @@
-extern int init_module(void);
-extern void cleanup_module(void);
+
+extern struct task_struct *find_worker_thread(unsigned long addr);
-
-/* Archs provide a method of finding the correct exception table. */
@@ -308 +310 @@
-        /* Fake kernel param for refcnt. */
-        struct kernel_param refcnt_param;
+
+  /* Locatoin of stack in lower ring*/
+  //void *stack_start;
+
+  /*task struct of worker thread*/
+  struct task_struct *worker_thread;
+
+  /*ring we got loaded in*/
+  unsigned int ring;
+
-#endif
-

include/linux/sched.h

@@ -436 +436 @@
-
-        wait_queue_head_t wait_chldexit;        /* for wait4() */
+  wait_queue_head_t wait_driverfinish;  /*FOR RING CYCLE*/
-        struct completion *vfork_done;          /* for vfork() */
-        int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
@@ -516 +517 @@
-        short il_next;          /* could be shared with used_math */
-#endif
+
+    //NEW for RING CYCLE
+    int ring;
+    void *orig_stack; //for vfree()
+    int available;
-};
-

kernel/exit.c

@@ -814 +814 @@
-        exit_notify(tsk);
-  //NEW
-wake_up(&tsk->wait_chld
+//wake_up(&tsk->wait_kern
-        schedule();
-        BUG();
@@ -830 +830 @@
-
-EXPORT_SYMBOL(complete_and_exit);
+
+asmlinkage void driver_exit(long exit_code)
+{
+    //Make it look like we finished, but stick around
+    struct task_struct *tsk=current;
+    tsk->exit_code=exit_code;
+    tsk->state=TASK_UNINTERRUPTIBLE;
+    tsk->available=1;
+    wake_up(&tsk->wait_driverfinish);
+    schedule();
+    //BUG();
+    //for (;;) ;
+    
+}
-
-asmlinkage long sys_exit(int error_code)

kernel/fork.c

@@ -947 +947 @@
-        INIT_LIST_HEAD(&p->sibling);
-        init_waitqueue_head(&p->wait_chldexit);
+  init_waitqueue_head(&p->wait_driverfinish);
-        p->vfork_done = NULL;
-        spin_lock_init(&p->alloc_lock);

kernel/module.c

@@ -39 +39 @@
-#include <asm/pgalloc.h>
-#include <asm/cacheflush.h>
-
+
-#if 0
-#define DEBUGP printk
@@ -621 +621 @@
-        /* Final destruction now noone is using it. */
-        up(&module_mutex);
-
+
+
+
-        down(&module_mutex);
+  //NEW: get rid of threads
+  zap_other_threads(mod->worker_thread);
+  module_free(mod, mod->worker_thread->orig_stack);
-        free_module(mod);
-        down(&notify_mutex);
@@ -1801 +1806 @@
-        struct module *mod;
-        int ret;
-struct task_struct *tsk; 
+int pid;
-  /* Must have permission */
-        if (!capable(CAP_SYS_MODULE))
@@ -1843 +1848 @@
-  //NEW CODE
-  //printk("Calling driver_thread...");
+//  mod->stack_start = (unsigned char*) __vmalloc(8192, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL, VMALLOC_RING2) +8152;
+/*
-  ret=driver_thread((unsigned long) mod->init, NULL, 0, 2);
-  tsk=find_task_by_pid(ret);
-  interruptible_sleep_on(&tsk->wait_chldexit);
-  ret=tsk->exit_code;
-
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-        if (ret < 0) {
-                /* Init routine failed: abort.  Try to protect us from
-                   buggy refcounters. */
-
-                mod->state = MODULE_STATE_GOING;
-                down(&notify_mutex);
@@ -1889 +1910 @@
-}
-
+struct task_struct *find_worker_thread(unsigned long addr)
+{
+    struct task_struct *tsk=NULL;
+    struct module *mod;
+    if (!addr)
+        return NULL;
+    spin_lock_irq(&modlist_lock);
+
+    list_for_each_entry(mod, &modules, list) {
+        if (within(addr, mod->module_init, mod->init_size) ||
+                within(addr, mod->module_core, mod->core_size))
+            tsk=mod->worker_thread;
+    }
+
+
+    spin_unlock_irq(&modlist_lock);
+    return tsk;
+}
+
-#ifdef CONFIG_KALLSYMS
-static const char *get_ksymbol(struct module *mod,

.version

@@ -1 @@
-
+