Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 583 insertions, 0 deletions

diff --git a/arch/m32r/mm/fault.c b/arch/m32r/mm/fault.c
new file mode 100644
index 000000000000..bf7fb58ef02c
--- /dev/null
+++ b/arch/m32r/mm/fault.c
@@ -0,0 +1,583 @@
+/*
+ *  linux/arch/m32r/mm/fault.c
+ *
+ *  Copyright (c) 2001, 2002  Hitoshi Yamamoto, and H. Kondo
+ *  Copyright (c) 2004  Naoto Sugai, NIIBE Yutaka
+ *
+ *  Some code taken from i386 version.
+ *    Copyright (C) 1995  Linus Torvalds
+ */
+
+#include <linux/config.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/tty.h>
+#include <linux/vt_kern.h>              /* For unblank_screen() */
+#include <linux/highmem.h>
+#include <linux/module.h>
+
+#include <asm/m32r.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/hardirq.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+
+extern void die(const char *, struct pt_regs *, long);
+
+#ifndef CONFIG_SMP
+asmlinkage unsigned int tlb_entry_i_dat;
+asmlinkage unsigned int tlb_entry_d_dat;
+#define tlb_entry_i tlb_entry_i_dat
+#define tlb_entry_d tlb_entry_d_dat
+#else
+unsigned int tlb_entry_i_dat[NR_CPUS];
+unsigned int tlb_entry_d_dat[NR_CPUS];
+#define tlb_entry_i tlb_entry_i_dat[smp_processor_id()]
+#define tlb_entry_d tlb_entry_d_dat[smp_processor_id()]
+#endif
+
+extern void init_tlb(void);
+
+/*
+ * Unlock any spinlocks which will prevent us from getting the
+ * message out
+ */
+void bust_spinlocks(int yes)
+{
+        int loglevel_save = console_loglevel;
+
+        if (yes) {
+                oops_in_progress = 1;
+                return;
+        }
+#ifdef CONFIG_VT
+        unblank_screen();
+#endif
+        oops_in_progress = 0;
+        /*
+         * OK, the message is on the console.  Now we call printk()
+         * without oops_in_progress set so that printk will give klogd
+         * a poke.  Hold onto your hats...
+         */
+        console_loglevel = 15;          /* NMI oopser may have shut the console up */
+        printk(" ");
+        console_loglevel = loglevel_save;
+}
+
+/*======================================================================*
+ * do_page_fault()
+ *======================================================================*
+ * This routine handles page faults.  It determines the address,
+ * and the problem, and then passes it off to one of the appropriate
+ * routines.
+ *
+ * ARGUMENT:
+ *  regs       : M32R SP reg.
+ *  error_code : See below
+ *  address    : M32R MMU MDEVA reg. (Operand ACE)
+ *             : M32R BPC reg. (Instruction ACE)
+ *
+ * error_code :
+ *  bit 0 == 0 means no page found, 1 means protection fault
+ *  bit 1 == 0 means read, 1 means write
+ *  bit 2 == 0 means kernel, 1 means user-mode
+ *  bit 3 == 0 means data, 1 means instruction
+ *======================================================================*/
+#define ACE_PROTECTION          1
+#define ACE_WRITE               2
+#define ACE_USERMODE            4
+#define ACE_INSTRUCTION         8
+
+asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
+  unsigned long address)
+{
+        struct task_struct *tsk;
+        struct mm_struct *mm;
+        struct vm_area_struct * vma;
+        unsigned long page, addr;
+        int write;
+        siginfo_t info;
+
+        /*
+         * If BPSW IE bit enable --> set PSW IE bit
+         */
+        if (regs->psw & M32R_PSW_BIE)
+                local_irq_enable();
+
+        tsk = current;
+
+        info.si_code = SEGV_MAPERR;
+
+        /*
+         * We fault-in kernel-space virtual memory on-demand. The
+         * 'reference' page table is init_mm.pgd.
+         *
+         * NOTE! We MUST NOT take any locks for this case. We may
+         * be in an interrupt or a critical region, and should
+         * only copy the information from the master page table,
+         * nothing more.
+         *
+         * This verifies that the fault happens in kernel space
+         * (error_code & ACE_USERMODE) == 0, and that the fault was not a
+         * protection error (error_code & ACE_PROTECTION) == 0.
+         */
+        if (address >= TASK_SIZE && !(error_code & ACE_USERMODE))
+                goto vmalloc_fault;
+
+        mm = tsk->mm;
+
+        /*
+         * If we're in an interrupt or have no user context or are running in an
+         * atomic region then we must not take the fault..
+         */
+        if (in_atomic() || !mm)
+                goto bad_area_nosemaphore;
+
+        /* When running in the kernel we expect faults to occur only to
+         * addresses in user space.  All other faults represent errors in the
+         * kernel and should generate an OOPS.  Unfortunatly, in the case of an
+         * erroneous fault occuring in a code path which already holds mmap_sem
+         * we will deadlock attempting to validate the fault against the
+         * address space.  Luckily the kernel only validly references user
+         * space from well defined areas of code, which are listed in the
+         * exceptions table.
+         *
+         * As the vast majority of faults will be valid we will only perform
+         * the source reference check when there is a possibilty of a deadlock.
+         * Attempt to lock the address space, if we cannot we then validate the
+         * source.  If this is invalid we can skip the address space check,
+         * thus avoiding the deadlock.
+         */
+        if (!down_read_trylock(&mm->mmap_sem)) {
+                if ((error_code & ACE_USERMODE) == 0 &&
+                    !search_exception_tables(regs->psw))
+                        goto bad_area_nosemaphore;
+                down_read(&mm->mmap_sem);
+        }
+
+        vma = find_vma(mm, address);
+        if (!vma)
+                goto bad_area;
+        if (vma->vm_start <= address)
+                goto good_area;
+        if (!(vma->vm_flags & VM_GROWSDOWN))
+                goto bad_area;
+#if 0
+        if (error_code & ACE_USERMODE) {
+                /*
+                 * accessing the stack below "spu" is always a bug.
+                 * The "+ 4" is there due to the push instruction
+                 * doing pre-decrement on the stack and that
+                 * doesn't show up until later..
+                 */
+                if (address + 4 < regs->spu)
+                        goto bad_area;
+        }
+#endif
+        if (expand_stack(vma, address))
+                goto bad_area;
+/*
+ * Ok, we have a good vm_area for this memory access, so
+ * we can handle it..
+ */
+good_area:
+        info.si_code = SEGV_ACCERR;
+        write = 0;
+        switch (error_code & (ACE_WRITE|ACE_PROTECTION)) {
+                default:        /* 3: write, present */
+                        /* fall through */
+                case ACE_WRITE: /* write, not present */
+                        if (!(vma->vm_flags & VM_WRITE))
+                                goto bad_area;
+                        write++;
+                        break;
+                case ACE_PROTECTION:    /* read, present */
+                case 0:         /* read, not present */
+                        if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
+                                goto bad_area;
+        }
+
+        /*
+         * For instruction access exception, check if the area is executable
+         */
+        if ((error_code & ACE_INSTRUCTION) && !(vma->vm_flags & VM_EXEC))
+          goto bad_area;
+
+survive:
+        /*
+         * If for any reason at all we couldn't handle the fault,
+         * make sure we exit gracefully rather than endlessly redo
+         * the fault.
+         */
+        addr = (address & PAGE_MASK);
+        set_thread_fault_code(error_code);
+        switch (handle_mm_fault(mm, vma, addr, write)) {
+                case VM_FAULT_MINOR:
+                        tsk->min_flt++;
+                        break;
+                case VM_FAULT_MAJOR:
+                        tsk->maj_flt++;
+                        break;
+                case VM_FAULT_SIGBUS:
+                        goto do_sigbus;
+                case VM_FAULT_OOM:
+                        goto out_of_memory;
+                default:
+                        BUG();
+        }
+        set_thread_fault_code(0);
+        up_read(&mm->mmap_sem);
+        return;
+
+/*
+ * Something tried to access memory that isn't in our memory map..
+ * Fix it, but check if it's kernel or user first..
+ */
+bad_area:
+        up_read(&mm->mmap_sem);
+
+bad_area_nosemaphore:
+        /* User mode accesses just cause a SIGSEGV */
+        if (error_code & ACE_USERMODE) {
+                tsk->thread.address = address;
+                tsk->thread.error_code = error_code | (address >= TASK_SIZE);
+                tsk->thread.trap_no = 14;
+                info.si_signo = SIGSEGV;
+                info.si_errno = 0;
+                /* info.si_code has been set above */
+                info.si_addr = (void __user *)address;
+                force_sig_info(SIGSEGV, &info, tsk);
+                return;
+        }
+
+no_context:
+        /* Are we prepared to handle this kernel fault?  */
+        if (fixup_exception(regs))
+                return;
+
+/*
+ * Oops. The kernel tried to access some bad page. We'll have to
+ * terminate things with extreme prejudice.
+ */
+
+        bust_spinlocks(1);
+
+        if (address < PAGE_SIZE)
+                printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
+        else
+                printk(KERN_ALERT "Unable to handle kernel paging request");
+        printk(" at virtual address %08lx\n",address);
+        printk(KERN_ALERT " printing bpc:\n");
+        printk("%08lx\n", regs->bpc);
+        page = *(unsigned long *)MPTB;
+        page = ((unsigned long *) page)[address >> PGDIR_SHIFT];
+        printk(KERN_ALERT "*pde = %08lx\n", page);
+        if (page & _PAGE_PRESENT) {
+                page &= PAGE_MASK;
+                address &= 0x003ff000;
+                page = ((unsigned long *) __va(page))[address >> PAGE_SHIFT];
+                printk(KERN_ALERT "*pte = %08lx\n", page);
+        }
+        die("Oops", regs, error_code);
+        bust_spinlocks(0);
+        do_exit(SIGKILL);
+
+/*
+ * We ran out of memory, or some other thing happened to us that made
+ * us unable to handle the page fault gracefully.
+ */
+out_of_memory:
+        up_read(&mm->mmap_sem);
+        if (tsk->pid == 1) {
+                yield();
+                down_read(&mm->mmap_sem);
+                goto survive;
+        }
+        printk("VM: killing process %s\n", tsk->comm);
+        if (error_code & ACE_USERMODE)
+                do_exit(SIGKILL);
+        goto no_context;
+
+do_sigbus:
+        up_read(&mm->mmap_sem);
+
+        /* Kernel mode? Handle exception or die */
+        if (!(error_code & ACE_USERMODE))
+                goto no_context;
+
+        tsk->thread.address = address;
+        tsk->thread.error_code = error_code;
+        tsk->thread.trap_no = 14;
+        info.si_signo = SIGBUS;
+        info.si_errno = 0;
+        info.si_code = BUS_ADRERR;
+        info.si_addr = (void __user *)address;
+        force_sig_info(SIGBUS, &info, tsk);
+        return;
+
+vmalloc_fault:
+        {
+                /*
+                 * Synchronize this task's top level page-table
+                 * with the 'reference' page table.
+                 *
+                 * Do _not_ use "tsk" here. We might be inside
+                 * an interrupt in the middle of a task switch..
+                 */
+                int offset = pgd_index(address);
+                pgd_t *pgd, *pgd_k;
+                pmd_t *pmd, *pmd_k;
+                pte_t *pte_k;
+
+                pgd = (pgd_t *)*(unsigned long *)MPTB;
+                pgd = offset + (pgd_t *)pgd;
+                pgd_k = init_mm.pgd + offset;
+
+                if (!pgd_present(*pgd_k))
+                        goto no_context;
+
+                /*
+                 * set_pgd(pgd, *pgd_k); here would be useless on PAE
+                 * and redundant with the set_pmd() on non-PAE.
+                 */
+
+                pmd = pmd_offset(pgd, address);
+                pmd_k = pmd_offset(pgd_k, address);
+                if (!pmd_present(*pmd_k))
+                        goto no_context;
+                set_pmd(pmd, *pmd_k);
+
+                pte_k = pte_offset_kernel(pmd_k, address);
+                if (!pte_present(*pte_k))
+                        goto no_context;
+
+                addr = (address & PAGE_MASK) | (error_code & ACE_INSTRUCTION);
+                update_mmu_cache(NULL, addr, *pte_k);
+                return;
+        }
+}
+
+/*======================================================================*
+ * update_mmu_cache()
+ *======================================================================*/
+#define TLB_MASK        (NR_TLB_ENTRIES - 1)
+#define ITLB_END        (unsigned long *)(ITLB_BASE + (NR_TLB_ENTRIES * 8))
+#define DTLB_END        (unsigned long *)(DTLB_BASE + (NR_TLB_ENTRIES * 8))
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long vaddr,
+        pte_t pte)
+{
+        unsigned long *entry1, *entry2;
+        unsigned long pte_data, flags;
+        unsigned int *entry_dat;
+        int inst = get_thread_fault_code() & ACE_INSTRUCTION;
+        int i;
+
+        /* Ptrace may call this routine. */
+        if (vma && current->active_mm != vma->vm_mm)
+                return;
+
+        local_irq_save(flags);
+
+        vaddr = (vaddr & PAGE_MASK) | get_asid();
+
+#ifdef CONFIG_CHIP_OPSP
+        entry1 = (unsigned long *)ITLB_BASE;
+        for(i = 0 ; i < NR_TLB_ENTRIES; i++) {
+                if(*entry1++ == vaddr) {
+                        pte_data = pte_val(pte);
+                        set_tlb_data(entry1, pte_data);
+                        break;
+                }
+                entry1++;
+        }
+        entry2 = (unsigned long *)DTLB_BASE;
+        for(i = 0 ; i < NR_TLB_ENTRIES ; i++) {
+                if(*entry2++ == vaddr) {
+                        pte_data = pte_val(pte);
+                        set_tlb_data(entry2, pte_data);
+                        break;
+                }
+                entry2++;
+        }
+        local_irq_restore(flags);
+        return;
+#else
+        pte_data = pte_val(pte);
+
+        /*
+         * Update TLB entries
+         *  entry1: ITLB entry address
+         *  entry2: DTLB entry address
+         */
+        __asm__ __volatile__ (
+                "seth   %0, #high(%4)   \n\t"
+                "st     %2, @(%5, %0)   \n\t"
+                "ldi    %1, #1          \n\t"
+                "st     %1, @(%6, %0)   \n\t"
+                "add3   r4, %0, %7      \n\t"
+                ".fillinsn              \n"
+                "1:                     \n\t"
+                "ld     %1, @(%6, %0)   \n\t"
+                "bnez   %1, 1b          \n\t"
+                "ld     %0, @r4+        \n\t"
+                "ld     %1, @r4         \n\t"
+                "st     %3, @+%0        \n\t"
+                "st     %3, @+%1        \n\t"
+                : "=&r" (entry1), "=&r" (entry2)
+                : "r" (vaddr), "r" (pte_data), "i" (MMU_REG_BASE),
+                "i" (MSVA_offset), "i" (MTOP_offset), "i" (MIDXI_offset)
+                : "r4", "memory"
+        );
+
+        if ((!inst && entry2 >= DTLB_END) || (inst && entry1 >= ITLB_END))
+                goto notfound;
+
+found:
+        local_irq_restore(flags);
+
+        return;
+
+        /* Valid entry not found */
+notfound:
+        /*
+         * Update ITLB or DTLB entry
+         *  entry1: TLB entry address
+         *  entry2: TLB base address
+         */
+        if (!inst) {
+                entry2 = (unsigned long *)DTLB_BASE;
+                entry_dat = &tlb_entry_d;
+        } else {
+                entry2 = (unsigned long *)ITLB_BASE;
+                entry_dat = &tlb_entry_i;
+        }
+        entry1 = entry2 + (((*entry_dat - 1) & TLB_MASK) << 1);
+
+        for (i = 0 ; i < NR_TLB_ENTRIES ; i++) {
+                if (!(entry1[1] & 2))   /* Valid bit check */
+                        break;
+
+                if (entry1 != entry2)
+                        entry1 -= 2;
+                else
+                        entry1 += TLB_MASK << 1;
+        }
+
+        if (i >= NR_TLB_ENTRIES) {      /* Empty entry not found */
+                entry1 = entry2 + (*entry_dat << 1);
+                *entry_dat = (*entry_dat + 1) & TLB_MASK;
+        }
+        *entry1++ = vaddr;      /* Set TLB tag */
+        set_tlb_data(entry1, pte_data);
+
+        goto found;
+#endif
+}
+
+/*======================================================================*
+ * flush_tlb_page() : flushes one page
+ *======================================================================*/
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+        if (vma->vm_mm && mm_context(vma->vm_mm) != NO_CONTEXT) {
+                unsigned long flags;
+
+                local_irq_save(flags);
+                page &= PAGE_MASK;
+                page |= (mm_context(vma->vm_mm) & MMU_CONTEXT_ASID_MASK);
+                __flush_tlb_page(page);
+                local_irq_restore(flags);
+        }
+}
+
+/*======================================================================*
+ * flush_tlb_range() : flushes a range of pages
+ *======================================================================*/
+void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+        unsigned long end)
+{
+        struct mm_struct *mm;
+
+        mm = vma->vm_mm;
+        if (mm_context(mm) != NO_CONTEXT) {
+                unsigned long flags;
+                int size;
+
+                local_irq_save(flags);
+                size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+                if (size > (NR_TLB_ENTRIES / 4)) { /* Too many TLB to flush */
+                        mm_context(mm) = NO_CONTEXT;
+                        if (mm == current->mm)
+                                activate_context(mm);
+                } else {
+                        unsigned long asid;
+
+                        asid = mm_context(mm) & MMU_CONTEXT_ASID_MASK;
+                        start &= PAGE_MASK;
+                        end += (PAGE_SIZE - 1);
+                        end &= PAGE_MASK;
+
+                        start |= asid;
+                        end   |= asid;
+                        while (start < end) {
+                                __flush_tlb_page(start);
+                                start += PAGE_SIZE;
+                        }
+                }
+                local_irq_restore(flags);
+        }
+}
+
+/*======================================================================*
+ * flush_tlb_mm() : flushes the specified mm context TLB's
+ *======================================================================*/
+void local_flush_tlb_mm(struct mm_struct *mm)
+{
+        /* Invalidate all TLB of this process. */
+        /* Instead of invalidating each TLB, we get new MMU context. */
+        if (mm_context(mm) != NO_CONTEXT) {
+                unsigned long flags;
+
+                local_irq_save(flags);
+                mm_context(mm) = NO_CONTEXT;
+                if (mm == current->mm)
+                        activate_context(mm);
+                local_irq_restore(flags);
+        }
+}
+
+/*======================================================================*
+ * flush_tlb_all() : flushes all processes TLBs
+ *======================================================================*/
+void local_flush_tlb_all(void)
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+        __flush_tlb_all();
+        local_irq_restore(flags);
+}
+
+/*======================================================================*
+ * init_mmu()
+ *======================================================================*/
+void __init init_mmu(void)
+{
+        tlb_entry_i = 0;
+        tlb_entry_d = 0;
+        mmu_context_cache = MMU_CONTEXT_FIRST_VERSION;
+        set_asid(mmu_context_cache & MMU_CONTEXT_ASID_MASK);
+        *(volatile unsigned long *)MPTB = (unsigned long)swapper_pg_dir;
+}