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, 325 insertions, 0 deletions

diff --git a/arch/frv/mm/fault.c b/arch/frv/mm/fault.c
new file mode 100644
index 0000000..41d02ac
--- /dev/null
+++ b/arch/frv/mm/fault.c
@@ -0,0 +1,325 @@
+/*
+ *  linux/arch/frv/mm/fault.c
+ *
+ * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
+ * - Written by David Howells (dhowells@redhat.com)
+ * - Derived from arch/m68knommu/mm/fault.c
+ *   - Copyright (C) 1998  D. Jeff Dionne <jeff@lineo.ca>,
+ *   - Copyright (C) 2000  Lineo, Inc.  (www.lineo.com)
+ *
+ *  Based on:
+ *
+ *  linux/arch/m68k/mm/fault.c
+ *
+ *  Copyright (C) 1995  Hamish Macdonald
+ */
+
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/ptrace.h>
+#include <linux/hardirq.h>
+
+#include <asm/system.h>
+#include <asm/pgtable.h>
+#include <asm/uaccess.h>
+#include <asm/gdb-stub.h>
+
+/*****************************************************************************/
+/*
+ * This routine handles page faults.  It determines the problem, and
+ * then passes it off to one of the appropriate routines.
+ */
+asmlinkage void do_page_fault(int datammu, unsigned long esr0, unsigned long ear0)
+{
+	struct vm_area_struct *vma;
+	struct mm_struct *mm;
+	unsigned long _pme, lrai, lrad, fixup;
+	siginfo_t info;
+	pgd_t *pge;
+	pud_t *pue;
+	pte_t *pte;
+	int write;
+
+#if 0
+	const char *atxc[16] = {
+		[0x0] = "mmu-miss", [0x8] = "multi-dat", [0x9] = "multi-sat",
+		[0xa] = "tlb-miss", [0xc] = "privilege", [0xd] = "write-prot",
+	};
+
+	printk("do_page_fault(%d,%lx [%s],%lx)\n",
+	       datammu, esr0, atxc[esr0 >> 20 & 0xf], ear0);
+#endif
+
+	mm = current->mm;
+
+	/*
+	 * 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
+	 * and that the fault was a page not present (invalid) error
+	 */
+	if (!user_mode(__frame) && (esr0 & ESR0_ATXC) == ESR0_ATXC_AMRTLB_MISS) {
+		if (ear0 >= VMALLOC_START && ear0 < VMALLOC_END)
+			goto kernel_pte_fault;
+		if (ear0 >= PKMAP_BASE && ear0 < PKMAP_END)
+			goto kernel_pte_fault;
+	}
+
+	info.si_code = SEGV_MAPERR;
+
+	/*
+	 * If we're in an interrupt or have no user
+	 * context, we must not take the fault..
+	 */
+	if (in_interrupt() || !mm)
+		goto no_context;
+
+	down_read(&mm->mmap_sem);
+
+	vma = find_vma(mm, ear0);
+	if (!vma)
+		goto bad_area;
+	if (vma->vm_start <= ear0)
+		goto good_area;
+	if (!(vma->vm_flags & VM_GROWSDOWN))
+		goto bad_area;
+
+	if (user_mode(__frame)) {
+		/*
+		 * accessing the stack below %esp is always a bug.
+		 * The "+ 32" is there due to some instructions (like
+		 * pusha) doing post-decrement on the stack and that
+		 * doesn't show up until later..
+		 */
+		if ((ear0 & PAGE_MASK) + 2 * PAGE_SIZE < __frame->sp) {
+#if 0
+			printk("[%d] ### Access below stack @%lx (sp=%lx)\n",
+			       current->pid, ear0, __frame->sp);
+			show_registers(__frame);
+			printk("[%d] ### Code: [%08lx] %02x %02x %02x %02x %02x %02x %02x %02x\n",
+			       current->pid,
+			       __frame->pc,
+			       ((u8*)__frame->pc)[0],
+			       ((u8*)__frame->pc)[1],
+			       ((u8*)__frame->pc)[2],
+			       ((u8*)__frame->pc)[3],
+			       ((u8*)__frame->pc)[4],
+			       ((u8*)__frame->pc)[5],
+			       ((u8*)__frame->pc)[6],
+			       ((u8*)__frame->pc)[7]
+			       );
+#endif
+			goto bad_area;
+		}
+	}
+
+	if (expand_stack(vma, ear0))
+		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 (esr0 & ESR0_ATXC) {
+	default:
+		/* handle write to write protected page */
+	case ESR0_ATXC_WP_EXCEP:
+#ifdef TEST_VERIFY_AREA
+		if (!(user_mode(__frame)))
+			printk("WP fault at %08lx\n", __frame->pc);
+#endif
+		if (!(vma->vm_flags & VM_WRITE))
+			goto bad_area;
+		write = 1;
+		break;
+
+		 /* handle read from protected page */
+	case ESR0_ATXC_PRIV_EXCEP:
+		goto bad_area;
+
+		 /* handle read, write or exec on absent page
+		  * - can't support write without permitting read
+		  * - don't support execute without permitting read and vice-versa
+		  */
+	case ESR0_ATXC_AMRTLB_MISS:
+		if (!(vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)))
+			goto bad_area;
+		break;
+	}
+
+	/*
+	 * If for any reason at all we couldn't handle the fault,
+	 * make sure we exit gracefully rather than endlessly redo
+	 * the fault.
+	 */
+	switch (handle_mm_fault(mm, vma, ear0, write)) {
+	case 1:
+		current->min_flt++;
+		break;
+	case 2:
+		current->maj_flt++;
+		break;
+	case 0:
+		goto do_sigbus;
+	default:
+		goto out_of_memory;
+	}
+
+	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);
+
+	/* User mode accesses just cause a SIGSEGV */
+	if (user_mode(__frame)) {
+		info.si_signo = SIGSEGV;
+		info.si_errno = 0;
+		/* info.si_code has been set above */
+		info.si_addr = (void *) ear0;
+		force_sig_info(SIGSEGV, &info, current);
+		return;
+	}
+
+ no_context:
+	/* are we prepared to handle this kernel fault? */
+	if ((fixup = search_exception_table(__frame->pc)) != 0) {
+		__frame->pc = fixup;
+		return;
+	}
+
+/*
+ * Oops. The kernel tried to access some bad page. We'll have to
+ * terminate things with extreme prejudice.
+ */
+
+	bust_spinlocks(1);
+
+	if (ear0 < 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 addr %08lx\n", ear0);
+	printk("  PC  : %08lx\n", __frame->pc);
+	printk("  EXC : esr0=%08lx ear0=%08lx\n", esr0, ear0);
+
+	asm("lrai %1,%0,#1,#0,#0" : "=&r"(lrai) : "r"(ear0));
+	asm("lrad %1,%0,#1,#0,#0" : "=&r"(lrad) : "r"(ear0));
+
+	printk(KERN_ALERT "  LRAI: %08lx\n", lrai);
+	printk(KERN_ALERT "  LRAD: %08lx\n", lrad);
+
+	__break_hijack_kernel_event();
+
+	pge = pgd_offset(current->mm, ear0);
+	pue = pud_offset(pge, ear0);
+	_pme = pue->pue[0].ste[0];
+
+	printk(KERN_ALERT "  PGE : %8p { PME %08lx }\n", pge, _pme);
+
+	if (_pme & xAMPRx_V) {
+		unsigned long dampr, damlr, val;
+
+		asm volatile("movsg dampr2,%0 ! movgs %2,dampr2 ! movsg damlr2,%1"
+			     : "=&r"(dampr), "=r"(damlr)
+			     : "r" (_pme | xAMPRx_L|xAMPRx_SS_16Kb|xAMPRx_S|xAMPRx_C|xAMPRx_V)
+			     );
+
+		pte = (pte_t *) damlr + __pte_index(ear0);
+		val = pte_val(*pte);
+
+		asm volatile("movgs %0,dampr2" :: "r" (dampr));
+
+		printk(KERN_ALERT "  PTE : %8p { %08lx }\n", pte, val);
+	}
+
+	die_if_kernel("Oops\n");
+	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);
+	printk("VM: killing process %s\n", current->comm);
+	if (user_mode(__frame))
+		do_exit(SIGKILL);
+	goto no_context;
+
+ do_sigbus:
+	up_read(&mm->mmap_sem);
+
+	/*
+	 * Send a sigbus, regardless of whether we were in kernel
+	 * or user mode.
+	 */
+	info.si_signo = SIGBUS;
+	info.si_errno = 0;
+	info.si_code = BUS_ADRERR;
+	info.si_addr = (void *) ear0;
+	force_sig_info(SIGBUS, &info, current);
+
+	/* Kernel mode? Handle exceptions or die */
+	if (!user_mode(__frame))
+		goto no_context;
+	return;
+
+/*
+ * The fault was caused by a kernel PTE (such as installed by vmalloc or kmap)
+ */
+ kernel_pte_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 index = pgd_index(ear0);
+		pgd_t *pgd, *pgd_k;
+		pud_t *pud, *pud_k;
+		pmd_t *pmd, *pmd_k;
+		pte_t *pte_k;
+
+		pgd = (pgd_t *) __get_TTBR();
+		pgd = (pgd_t *)__va(pgd) + index;
+		pgd_k = ((pgd_t *)(init_mm.pgd)) + index;
+
+		if (!pgd_present(*pgd_k))
+			goto no_context;
+		//set_pgd(pgd, *pgd_k); /////// gcc ICE's on this line
+
+		pud_k = pud_offset(pgd_k, ear0);
+		if (!pud_present(*pud_k))
+			goto no_context;
+
+		pmd_k = pmd_offset(pud_k, ear0);
+		if (!pmd_present(*pmd_k))
+			goto no_context;
+
+		pud = pud_offset(pgd, ear0);
+		pmd = pmd_offset(pud, ear0);
+		set_pmd(pmd, *pmd_k);
+
+		pte_k = pte_offset_kernel(pmd_k, ear0);
+		if (!pte_present(*pte_k))
+			goto no_context;
+		return;
+	}
+} /* end do_page_fault() */