-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 1995 - 2000 by Ralf Baechle
- */
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/interrupt.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/vt_kern.h> /* For unblank_screen() */
-#include <linux/module.h>
-
-#include <asm/branch.h>
-#include <asm/hardirq.h>
-#include <asm/mmu_context.h>
-#include <asm/system.h>
-#include <asm/uaccess.h>
-#include <asm/ptrace.h>
-
-/*
- * This routine handles page faults. It determines the address,
- * and the problem, and then passes it off to one of the appropriate
- * routines.
- */
-asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
- unsigned long address)
-{
- struct vm_area_struct * vma = NULL;
- struct task_struct *tsk = current;
- struct mm_struct *mm = tsk->mm;
- const int field = sizeof(unsigned long) * 2;
- siginfo_t info;
-
-#if 0
- printk("Cpu%d[%s:%d:%0*lx:%ld:%0*lx]\n", smp_processor_id(),
- current->comm, current->pid, field, address, write,
- field, regs->cp0_epc);
-#endif
-
- 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.
- */
- if (unlikely(address >= VMALLOC_START))
- goto vmalloc_fault;
-
- /*
- * If we're in an interrupt or have no user
- * context, we must not take the fault..
- */
- if (in_atomic() || !mm)
- 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 (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;
-
- if (write) {
- if (!(vma->vm_flags & VM_WRITE))
- goto bad_area;
- } else {
- if (!(vma->vm_flags & (VM_READ | 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.
- */
- switch (handle_mm_fault(mm, vma, address, 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();
- }
-
- 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 (user_mode(regs)) {
- tsk->thread.cp0_badvaddr = address;
- tsk->thread.error_code = write;
-#if 0
- printk("do_page_fault() #2: sending SIGSEGV to %s for "
- "invalid %s\n%0*lx (epc == %0*lx, ra == %0*lx)\n",
- tsk->comm,
- write ? "write access to" : "read access from",
- field, address,
- field, (unsigned long) regs->cp0_epc,
- field, (unsigned long) regs->regs[31]);
-#endif
- info.si_signo = SIGSEGV;
- info.si_errno = 0;
- /* info.si_code has been set above */
- info.si_addr = (void *) address;
- force_sig_info(SIGSEGV, &info, tsk);
- return;
- }
-
-no_context:
- /* Are we prepared to handle this kernel fault? */
- if (fixup_exception(regs)) {
- current->thread.cp0_baduaddr = address;
- return;
- }
-
- /*
- * Oops. The kernel tried to access some bad page. We'll have to
- * terminate things with extreme prejudice.
- */
-
- bust_spinlocks(1);
-
- printk(KERN_ALERT "CPU %d Unable to handle kernel paging request at "
- "virtual address %0*lx, epc == %0*lx, ra == %0*lx\n",
- smp_processor_id(), field, address, field, regs->cp0_epc,
- field, regs->regs[31]);
- die("Oops", regs);
-
-/*
- * 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 (user_mode(regs))
- do_exit(SIGKILL);
- goto no_context;
-
-do_sigbus:
- up_read(&mm->mmap_sem);
-
- /* Kernel mode? Handle exceptions or die */
- if (!user_mode(regs))
- goto no_context;
-
- /*
- * Send a sigbus, regardless of whether we were in kernel
- * or user mode.
- */
- tsk->thread.cp0_badvaddr = address;
- info.si_signo = SIGBUS;
- info.si_errno = 0;
- info.si_code = BUS_ADRERR;
- info.si_addr = (void *) 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_offset(address);
- pgd_t *pgd, *pgd_k;
- pmd_t *pmd, *pmd_k;
- pte_t *pte_k;
-
- pgd = (pgd_t *) pgd_current[smp_processor_id()] + offset;
- pgd_k = init_mm.pgd + offset;
-
- if (!pgd_present(*pgd_k))
- goto no_context;
- set_pgd(pgd, *pgd_k);
-
- 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;
- return;
- }
-}
+/*\r
+ * This file is subject to the terms and conditions of the GNU General Public\r
+ * License. See the file "COPYING" in the main directory of this archive\r
+ * for more details.\r
+ *\r
+ * Copyright (C) 1995 - 2000 by Ralf Baechle\r
+ */\r
+#include <linux/signal.h>\r
+#include <linux/sched.h>\r
+#include <linux/interrupt.h>\r
+#include <linux/kernel.h>\r
+#include <linux/errno.h>\r
+#include <linux/string.h>\r
+#include <linux/types.h>\r
+#include <linux/ptrace.h>\r
+#include <linux/mman.h>\r
+#include <linux/mm.h>\r
+#include <linux/smp.h>\r
+#include <linux/smp_lock.h>\r
+#include <linux/vt_kern.h> /* For unblank_screen() */\r
+#include <linux/module.h>\r
+\r
+#include <asm/branch.h>\r
+#include <asm/hardirq.h>\r
+#include <asm/mmu_context.h>\r
+#include <asm/system.h>\r
+#include <asm/uaccess.h>\r
+#include <asm/ptrace.h>\r
+\r
+/*\r
+ * This routine handles page faults. It determines the address,\r
+ * and the problem, and then passes it off to one of the appropriate\r
+ * routines.\r
+ */\r
+asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,\r
+ unsigned long address)\r
+{\r
+ struct vm_area_struct * vma = NULL;\r
+ struct task_struct *tsk = current;\r
+ struct mm_struct *mm = tsk->mm;\r
+ const int field = sizeof(unsigned long) * 2;\r
+ siginfo_t info;\r
+\r
+#if 0\r
+ printk("Cpu%d[%s:%d:%0*lx:%ld:%0*lx]\n", smp_processor_id(),\r
+ current->comm, current->pid, field, address, write,\r
+ field, regs->cp0_epc);\r
+#endif\r
+\r
+ info.si_code = SEGV_MAPERR;\r
+\r
+ /*\r
+ * We fault-in kernel-space virtual memory on-demand. The\r
+ * 'reference' page table is init_mm.pgd.\r
+ *\r
+ * NOTE! We MUST NOT take any locks for this case. We may\r
+ * be in an interrupt or a critical region, and should\r
+ * only copy the information from the master page table,\r
+ * nothing more.\r
+ */\r
+ if (unlikely(address >= VMALLOC_START))\r
+ goto vmalloc_fault;\r
+\r
+ /*\r
+ * If we're in an interrupt or have no user\r
+ * context, we must not take the fault..\r
+ */\r
+ if (in_atomic() || !mm)\r
+ goto bad_area_nosemaphore;\r
+\r
+ down_read(&mm->mmap_sem);\r
+ vma = find_vma(mm, address);\r
+ if (!vma)\r
+ goto bad_area;\r
+ if (vma->vm_start <= address)\r
+ goto good_area;\r
+ if (!(vma->vm_flags & VM_GROWSDOWN))\r
+ goto bad_area;\r
+ if (expand_stack(vma, address))\r
+ goto bad_area;\r
+/*\r
+ * Ok, we have a good vm_area for this memory access, so\r
+ * we can handle it..\r
+ */\r
+good_area:\r
+ info.si_code = SEGV_ACCERR;\r
+\r
+ if (write) {\r
+ if (!(vma->vm_flags & VM_WRITE))\r
+ goto bad_area;\r
+ } else {\r
+ if (!(vma->vm_flags & (VM_READ | VM_EXEC)))\r
+ goto bad_area;\r
+ }\r
+\r
+survive:\r
+ /*\r
+ * If for any reason at all we couldn't handle the fault,\r
+ * make sure we exit gracefully rather than endlessly redo\r
+ * the fault.\r
+ */\r
+ switch (handle_mm_fault(mm, vma, address, write)) {\r
+ case VM_FAULT_MINOR:\r
+ tsk->min_flt++;\r
+ break;\r
+ case VM_FAULT_MAJOR:\r
+ tsk->maj_flt++;\r
+ break;\r
+ case VM_FAULT_SIGBUS:\r
+ goto do_sigbus;\r
+ case VM_FAULT_OOM:\r
+ goto out_of_memory;\r
+ default:\r
+ BUG();\r
+ }\r
+\r
+ up_read(&mm->mmap_sem);\r
+ return;\r
+\r
+/*\r
+ * Something tried to access memory that isn't in our memory map..\r
+ * Fix it, but check if it's kernel or user first..\r
+ */\r
+bad_area:\r
+ up_read(&mm->mmap_sem);\r
+\r
+bad_area_nosemaphore:\r
+ /* User mode accesses just cause a SIGSEGV */\r
+ if (user_mode(regs)) {\r
+ tsk->thread.cp0_badvaddr = address;\r
+ tsk->thread.error_code = write;\r
+#if 1\r
+ printk("do_page_fault() #2: sending SIGSEGV to %s for "\r
+ "invalid %s\n%0*lx (epc == %0*lx, ra == %0*lx)\n",\r
+ tsk->comm,\r
+ write ? "write access to" : "read access from",\r
+ field, address,\r
+ field, (unsigned long) regs->cp0_epc,\r
+ field, (unsigned long) regs->regs[31]);\r
+#endif\r
+ info.si_signo = SIGSEGV;\r
+ info.si_errno = 0;\r
+ /* info.si_code has been set above */\r
+ info.si_addr = (void *) address;\r
+ force_sig_info(SIGSEGV, &info, tsk);\r
+ return;\r
+ }\r
+\r
+no_context:\r
+ /* Are we prepared to handle this kernel fault? */\r
+ if (fixup_exception(regs)) {\r
+ current->thread.cp0_baduaddr = address;\r
+ return;\r
+ }\r
+\r
+ /*\r
+ * Oops. The kernel tried to access some bad page. We'll have to\r
+ * terminate things with extreme prejudice.\r
+ */\r
+\r
+ bust_spinlocks(1);\r
+\r
+ printk(KERN_ALERT "CPU %d Unable to handle kernel paging request at "\r
+ "virtual address %0*lx, epc == %0*lx, ra == %0*lx\n",\r
+ smp_processor_id(), field, address, field, regs->cp0_epc,\r
+ field, regs->regs[31]);\r
+ die("Oops", regs);\r
+\r
+/*\r
+ * We ran out of memory, or some other thing happened to us that made\r
+ * us unable to handle the page fault gracefully.\r
+ */\r
+out_of_memory:\r
+ up_read(&mm->mmap_sem);\r
+ if (tsk->pid == 1) {\r
+ yield();\r
+ down_read(&mm->mmap_sem);\r
+ goto survive;\r
+ }\r
+ printk("VM: killing process %s\n", tsk->comm);\r
+ if (user_mode(regs))\r
+ do_exit(SIGKILL);\r
+ goto no_context;\r
+\r
+do_sigbus:\r
+ up_read(&mm->mmap_sem);\r
+\r
+ /* Kernel mode? Handle exceptions or die */\r
+ if (!user_mode(regs))\r
+ goto no_context;\r
+\r
+ /*\r
+ * Send a sigbus, regardless of whether we were in kernel\r
+ * or user mode.\r
+ */\r
+ tsk->thread.cp0_badvaddr = address;\r
+ info.si_signo = SIGBUS;\r
+ info.si_errno = 0;\r
+ info.si_code = BUS_ADRERR;\r
+ info.si_addr = (void *) address;\r
+ force_sig_info(SIGBUS, &info, tsk);\r
+\r
+ return;\r
+\r
+vmalloc_fault:\r
+ {\r
+ /*\r
+ * Synchronize this task's top level page-table\r
+ * with the 'reference' page table.\r
+ *\r
+ * Do _not_ use "tsk" here. We might be inside\r
+ * an interrupt in the middle of a task switch..\r
+ */\r
+ int offset = __pgd_offset(address);\r
+ pgd_t *pgd, *pgd_k;\r
+ pmd_t *pmd, *pmd_k;\r
+ pte_t *pte_k;\r
+\r
+ pgd = (pgd_t *) pgd_current[smp_processor_id()] + offset;\r
+ pgd_k = init_mm.pgd + offset;\r
+\r
+ if (!pgd_present(*pgd_k))\r
+ goto no_context;\r
+ set_pgd(pgd, *pgd_k);\r
+\r
+ pmd = pmd_offset(pgd, address);\r
+ pmd_k = pmd_offset(pgd_k, address);\r
+ if (!pmd_present(*pmd_k))\r
+ goto no_context;\r
+ set_pmd(pmd, *pmd_k);\r
+\r
+ pte_k = pte_offset_kernel(pmd_k, address);\r
+ if (!pte_present(*pte_k))\r
+ goto no_context;\r
+ return;\r
+ }\r
+}\r
projects / bcm963xx.git / blobdiff