| /* |
| * S390 version |
| * Copyright IBM Corp. 1999 |
| * Author(s): Hartmut Penner (hp@de.ibm.com) |
| * Ulrich Weigand (uweigand@de.ibm.com) |
| * |
| * Derived from "arch/i386/mm/fault.c" |
| * Copyright (C) 1995 Linus Torvalds |
| */ |
| |
| #include <linux/kernel_stat.h> |
| #include <linux/perf_event.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/compat.h> |
| #include <linux/smp.h> |
| #include <linux/kdebug.h> |
| #include <linux/init.h> |
| #include <linux/console.h> |
| #include <linux/module.h> |
| #include <linux/hardirq.h> |
| #include <linux/kprobes.h> |
| #include <linux/uaccess.h> |
| #include <linux/hugetlb.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/diag.h> |
| #include <asm/pgtable.h> |
| #include <asm/irq.h> |
| #include <asm/mmu_context.h> |
| #include <asm/facility.h> |
| #include "../kernel/entry.h" |
| |
| #define __FAIL_ADDR_MASK -4096L |
| #define __SUBCODE_MASK 0x0600 |
| #define __PF_RES_FIELD 0x8000000000000000ULL |
| |
| #define VM_FAULT_BADCONTEXT 0x010000 |
| #define VM_FAULT_BADMAP 0x020000 |
| #define VM_FAULT_BADACCESS 0x040000 |
| #define VM_FAULT_SIGNAL 0x080000 |
| #define VM_FAULT_PFAULT 0x100000 |
| |
| static unsigned long store_indication __read_mostly; |
| |
| static int __init fault_init(void) |
| { |
| if (test_facility(75)) |
| store_indication = 0xc00; |
| return 0; |
| } |
| early_initcall(fault_init); |
| |
| static inline int notify_page_fault(struct pt_regs *regs) |
| { |
| int ret = 0; |
| |
| /* kprobe_running() needs smp_processor_id() */ |
| if (kprobes_built_in() && !user_mode(regs)) { |
| preempt_disable(); |
| if (kprobe_running() && kprobe_fault_handler(regs, 14)) |
| ret = 1; |
| preempt_enable(); |
| } |
| return ret; |
| } |
| |
| |
| /* |
| * Unlock any spinlocks which will prevent us from getting the |
| * message out. |
| */ |
| void bust_spinlocks(int yes) |
| { |
| if (yes) { |
| oops_in_progress = 1; |
| } else { |
| int loglevel_save = console_loglevel; |
| console_unblank(); |
| 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; |
| printk(" "); |
| console_loglevel = loglevel_save; |
| } |
| } |
| |
| /* |
| * Returns the address space associated with the fault. |
| * Returns 0 for kernel space and 1 for user space. |
| */ |
| static inline int user_space_fault(struct pt_regs *regs) |
| { |
| unsigned long trans_exc_code; |
| |
| /* |
| * The lowest two bits of the translation exception |
| * identification indicate which paging table was used. |
| */ |
| trans_exc_code = regs->int_parm_long & 3; |
| if (trans_exc_code == 3) /* home space -> kernel */ |
| return 0; |
| if (user_mode(regs)) |
| return 1; |
| if (trans_exc_code == 2) /* secondary space -> set_fs */ |
| return current->thread.mm_segment.ar4; |
| if (current->flags & PF_VCPU) |
| return 1; |
| return 0; |
| } |
| |
| static int bad_address(void *p) |
| { |
| unsigned long dummy; |
| |
| return probe_kernel_address((unsigned long *)p, dummy); |
| } |
| |
| static void dump_pagetable(unsigned long asce, unsigned long address) |
| { |
| unsigned long *table = __va(asce & PAGE_MASK); |
| |
| pr_alert("AS:%016lx ", asce); |
| switch (asce & _ASCE_TYPE_MASK) { |
| case _ASCE_TYPE_REGION1: |
| table = table + ((address >> 53) & 0x7ff); |
| if (bad_address(table)) |
| goto bad; |
| pr_cont("R1:%016lx ", *table); |
| if (*table & _REGION_ENTRY_INVALID) |
| goto out; |
| table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); |
| /* fallthrough */ |
| case _ASCE_TYPE_REGION2: |
| table = table + ((address >> 42) & 0x7ff); |
| if (bad_address(table)) |
| goto bad; |
| pr_cont("R2:%016lx ", *table); |
| if (*table & _REGION_ENTRY_INVALID) |
| goto out; |
| table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); |
| /* fallthrough */ |
| case _ASCE_TYPE_REGION3: |
| table = table + ((address >> 31) & 0x7ff); |
| if (bad_address(table)) |
| goto bad; |
| pr_cont("R3:%016lx ", *table); |
| if (*table & (_REGION_ENTRY_INVALID | _REGION3_ENTRY_LARGE)) |
| goto out; |
| table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); |
| /* fallthrough */ |
| case _ASCE_TYPE_SEGMENT: |
| table = table + ((address >> 20) & 0x7ff); |
| if (bad_address(table)) |
| goto bad; |
| pr_cont("S:%016lx ", *table); |
| if (*table & (_SEGMENT_ENTRY_INVALID | _SEGMENT_ENTRY_LARGE)) |
| goto out; |
| table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN); |
| } |
| table = table + ((address >> 12) & 0xff); |
| if (bad_address(table)) |
| goto bad; |
| pr_cont("P:%016lx ", *table); |
| out: |
| pr_cont("\n"); |
| return; |
| bad: |
| pr_cont("BAD\n"); |
| } |
| |
| static void dump_fault_info(struct pt_regs *regs) |
| { |
| unsigned long asce; |
| |
| pr_alert("Fault in "); |
| switch (regs->int_parm_long & 3) { |
| case 3: |
| pr_cont("home space "); |
| break; |
| case 2: |
| pr_cont("secondary space "); |
| break; |
| case 1: |
| pr_cont("access register "); |
| break; |
| case 0: |
| pr_cont("primary space "); |
| break; |
| } |
| pr_cont("mode while using "); |
| if (!user_space_fault(regs)) { |
| asce = S390_lowcore.kernel_asce; |
| pr_cont("kernel "); |
| } |
| #ifdef CONFIG_PGSTE |
| else if ((current->flags & PF_VCPU) && S390_lowcore.gmap) { |
| struct gmap *gmap = (struct gmap *)S390_lowcore.gmap; |
| asce = gmap->asce; |
| pr_cont("gmap "); |
| } |
| #endif |
| else { |
| asce = S390_lowcore.user_asce; |
| pr_cont("user "); |
| } |
| pr_cont("ASCE.\n"); |
| dump_pagetable(asce, regs->int_parm_long & __FAIL_ADDR_MASK); |
| } |
| |
| static inline void report_user_fault(struct pt_regs *regs, long signr) |
| { |
| if ((task_pid_nr(current) > 1) && !show_unhandled_signals) |
| return; |
| if (!unhandled_signal(current, signr)) |
| return; |
| if (!printk_ratelimit()) |
| return; |
| printk(KERN_ALERT "User process fault: interruption code %04x ilc:%d ", |
| regs->int_code & 0xffff, regs->int_code >> 17); |
| print_vma_addr(KERN_CONT "in ", regs->psw.addr); |
| printk(KERN_CONT "\n"); |
| printk(KERN_ALERT "failing address: %016lx TEID: %016lx\n", |
| regs->int_parm_long & __FAIL_ADDR_MASK, regs->int_parm_long); |
| dump_fault_info(regs); |
| show_regs(regs); |
| } |
| |
| /* |
| * Send SIGSEGV to task. This is an external routine |
| * to keep the stack usage of do_page_fault small. |
| */ |
| static noinline void do_sigsegv(struct pt_regs *regs, int si_code) |
| { |
| struct siginfo si; |
| |
| report_user_fault(regs, SIGSEGV); |
| si.si_signo = SIGSEGV; |
| si.si_code = si_code; |
| si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK); |
| force_sig_info(SIGSEGV, &si, current); |
| } |
| |
| static noinline void do_no_context(struct pt_regs *regs) |
| { |
| const struct exception_table_entry *fixup; |
| |
| /* Are we prepared to handle this kernel fault? */ |
| fixup = search_exception_tables(regs->psw.addr); |
| if (fixup) { |
| regs->psw.addr = extable_fixup(fixup); |
| return; |
| } |
| |
| /* |
| * Oops. The kernel tried to access some bad page. We'll have to |
| * terminate things with extreme prejudice. |
| */ |
| if (!user_space_fault(regs)) |
| printk(KERN_ALERT "Unable to handle kernel pointer dereference" |
| " in virtual kernel address space\n"); |
| else |
| printk(KERN_ALERT "Unable to handle kernel paging request" |
| " in virtual user address space\n"); |
| printk(KERN_ALERT "failing address: %016lx TEID: %016lx\n", |
| regs->int_parm_long & __FAIL_ADDR_MASK, regs->int_parm_long); |
| dump_fault_info(regs); |
| die(regs, "Oops"); |
| do_exit(SIGKILL); |
| } |
| |
| static noinline void do_low_address(struct pt_regs *regs) |
| { |
| /* Low-address protection hit in kernel mode means |
| NULL pointer write access in kernel mode. */ |
| if (regs->psw.mask & PSW_MASK_PSTATE) { |
| /* Low-address protection hit in user mode 'cannot happen'. */ |
| die (regs, "Low-address protection"); |
| do_exit(SIGKILL); |
| } |
| |
| do_no_context(regs); |
| } |
| |
| static noinline void do_sigbus(struct pt_regs *regs) |
| { |
| struct task_struct *tsk = current; |
| struct siginfo si; |
| |
| /* |
| * Send a sigbus, regardless of whether we were in kernel |
| * or user mode. |
| */ |
| si.si_signo = SIGBUS; |
| si.si_errno = 0; |
| si.si_code = BUS_ADRERR; |
| si.si_addr = (void __user *)(regs->int_parm_long & __FAIL_ADDR_MASK); |
| force_sig_info(SIGBUS, &si, tsk); |
| } |
| |
| static noinline void do_fault_error(struct pt_regs *regs, int fault) |
| { |
| int si_code; |
| |
| switch (fault) { |
| case VM_FAULT_BADACCESS: |
| case VM_FAULT_BADMAP: |
| /* Bad memory access. Check if it is kernel or user space. */ |
| if (user_mode(regs)) { |
| /* User mode accesses just cause a SIGSEGV */ |
| si_code = (fault == VM_FAULT_BADMAP) ? |
| SEGV_MAPERR : SEGV_ACCERR; |
| do_sigsegv(regs, si_code); |
| return; |
| } |
| case VM_FAULT_BADCONTEXT: |
| case VM_FAULT_PFAULT: |
| do_no_context(regs); |
| break; |
| case VM_FAULT_SIGNAL: |
| if (!user_mode(regs)) |
| do_no_context(regs); |
| break; |
| default: /* fault & VM_FAULT_ERROR */ |
| if (fault & VM_FAULT_OOM) { |
| if (!user_mode(regs)) |
| do_no_context(regs); |
| else |
| pagefault_out_of_memory(); |
| } else if (fault & VM_FAULT_SIGSEGV) { |
| /* Kernel mode? Handle exceptions or die */ |
| if (!user_mode(regs)) |
| do_no_context(regs); |
| else |
| do_sigsegv(regs, SEGV_MAPERR); |
| } else if (fault & VM_FAULT_SIGBUS) { |
| /* Kernel mode? Handle exceptions or die */ |
| if (!user_mode(regs)) |
| do_no_context(regs); |
| else |
| do_sigbus(regs); |
| } else |
| BUG(); |
| break; |
| } |
| } |
| |
| /* |
| * This routine handles page faults. It determines the address, |
| * and the problem, and then passes it off to one of the appropriate |
| * routines. |
| * |
| * interruption code (int_code): |
| * 04 Protection -> Write-Protection (suprression) |
| * 10 Segment translation -> Not present (nullification) |
| * 11 Page translation -> Not present (nullification) |
| * 3b Region third trans. -> Not present (nullification) |
| */ |
| static inline int do_exception(struct pt_regs *regs, int access) |
| { |
| #ifdef CONFIG_PGSTE |
| struct gmap *gmap; |
| #endif |
| struct task_struct *tsk; |
| struct mm_struct *mm; |
| struct vm_area_struct *vma; |
| unsigned long trans_exc_code; |
| unsigned long address; |
| unsigned int flags; |
| int fault; |
| |
| tsk = current; |
| /* |
| * The instruction that caused the program check has |
| * been nullified. Don't signal single step via SIGTRAP. |
| */ |
| clear_pt_regs_flag(regs, PIF_PER_TRAP); |
| |
| if (notify_page_fault(regs)) |
| return 0; |
| |
| mm = tsk->mm; |
| trans_exc_code = regs->int_parm_long; |
| |
| /* |
| * Verify that the fault happened in user space, that |
| * we are not in an interrupt and that there is a |
| * user context. |
| */ |
| fault = VM_FAULT_BADCONTEXT; |
| if (unlikely(!user_space_fault(regs) || faulthandler_disabled() || !mm)) |
| goto out; |
| |
| address = trans_exc_code & __FAIL_ADDR_MASK; |
| perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); |
| flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; |
| if (user_mode(regs)) |
| flags |= FAULT_FLAG_USER; |
| if (access == VM_WRITE || (trans_exc_code & store_indication) == 0x400) |
| flags |= FAULT_FLAG_WRITE; |
| down_read(&mm->mmap_sem); |
| |
| #ifdef CONFIG_PGSTE |
| gmap = (current->flags & PF_VCPU) ? |
| (struct gmap *) S390_lowcore.gmap : NULL; |
| if (gmap) { |
| current->thread.gmap_addr = address; |
| address = __gmap_translate(gmap, address); |
| if (address == -EFAULT) { |
| fault = VM_FAULT_BADMAP; |
| goto out_up; |
| } |
| if (gmap->pfault_enabled) |
| flags |= FAULT_FLAG_RETRY_NOWAIT; |
| } |
| #endif |
| |
| retry: |
| fault = VM_FAULT_BADMAP; |
| vma = find_vma(mm, address); |
| if (!vma) |
| goto out_up; |
| |
| if (unlikely(vma->vm_start > address)) { |
| if (!(vma->vm_flags & VM_GROWSDOWN)) |
| goto out_up; |
| if (expand_stack(vma, address)) |
| goto out_up; |
| } |
| |
| /* |
| * Ok, we have a good vm_area for this memory access, so |
| * we can handle it.. |
| */ |
| fault = VM_FAULT_BADACCESS; |
| if (unlikely(!(vma->vm_flags & access))) |
| goto out_up; |
| |
| if (is_vm_hugetlb_page(vma)) |
| address &= HPAGE_MASK; |
| /* |
| * If for any reason at all we couldn't handle the fault, |
| * make sure we exit gracefully rather than endlessly redo |
| * the fault. |
| */ |
| fault = handle_mm_fault(mm, vma, address, flags); |
| /* No reason to continue if interrupted by SIGKILL. */ |
| if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) { |
| fault = VM_FAULT_SIGNAL; |
| goto out; |
| } |
| if (unlikely(fault & VM_FAULT_ERROR)) |
| goto out_up; |
| |
| /* |
| * Major/minor page fault accounting is only done on the |
| * initial attempt. If we go through a retry, it is extremely |
| * likely that the page will be found in page cache at that point. |
| */ |
| if (flags & FAULT_FLAG_ALLOW_RETRY) { |
| if (fault & VM_FAULT_MAJOR) { |
| tsk->maj_flt++; |
| perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, |
| regs, address); |
| } else { |
| tsk->min_flt++; |
| perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, |
| regs, address); |
| } |
| if (fault & VM_FAULT_RETRY) { |
| #ifdef CONFIG_PGSTE |
| if (gmap && (flags & FAULT_FLAG_RETRY_NOWAIT)) { |
| /* FAULT_FLAG_RETRY_NOWAIT has been set, |
| * mmap_sem has not been released */ |
| current->thread.gmap_pfault = 1; |
| fault = VM_FAULT_PFAULT; |
| goto out_up; |
| } |
| #endif |
| /* Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk |
| * of starvation. */ |
| flags &= ~(FAULT_FLAG_ALLOW_RETRY | |
| FAULT_FLAG_RETRY_NOWAIT); |
| flags |= FAULT_FLAG_TRIED; |
| down_read(&mm->mmap_sem); |
| goto retry; |
| } |
| } |
| #ifdef CONFIG_PGSTE |
| if (gmap) { |
| address = __gmap_link(gmap, current->thread.gmap_addr, |
| address); |
| if (address == -EFAULT) { |
| fault = VM_FAULT_BADMAP; |
| goto out_up; |
| } |
| if (address == -ENOMEM) { |
| fault = VM_FAULT_OOM; |
| goto out_up; |
| } |
| } |
| #endif |
| fault = 0; |
| out_up: |
| up_read(&mm->mmap_sem); |
| out: |
| return fault; |
| } |
| |
| void do_protection_exception(struct pt_regs *regs) |
| { |
| unsigned long trans_exc_code; |
| int fault; |
| |
| trans_exc_code = regs->int_parm_long; |
| /* |
| * Protection exceptions are suppressing, decrement psw address. |
| * The exception to this rule are aborted transactions, for these |
| * the PSW already points to the correct location. |
| */ |
| if (!(regs->int_code & 0x200)) |
| regs->psw.addr = __rewind_psw(regs->psw, regs->int_code >> 16); |
| /* |
| * Check for low-address protection. This needs to be treated |
| * as a special case because the translation exception code |
| * field is not guaranteed to contain valid data in this case. |
| */ |
| if (unlikely(!(trans_exc_code & 4))) { |
| do_low_address(regs); |
| return; |
| } |
| fault = do_exception(regs, VM_WRITE); |
| if (unlikely(fault)) |
| do_fault_error(regs, fault); |
| } |
| NOKPROBE_SYMBOL(do_protection_exception); |
| |
| void do_dat_exception(struct pt_regs *regs) |
| { |
| int access, fault; |
| |
| access = VM_READ | VM_EXEC | VM_WRITE; |
| fault = do_exception(regs, access); |
| if (unlikely(fault)) |
| do_fault_error(regs, fault); |
| } |
| NOKPROBE_SYMBOL(do_dat_exception); |
| |
| #ifdef CONFIG_PFAULT |
| /* |
| * 'pfault' pseudo page faults routines. |
| */ |
| static int pfault_disable; |
| |
| static int __init nopfault(char *str) |
| { |
| pfault_disable = 1; |
| return 1; |
| } |
| |
| __setup("nopfault", nopfault); |
| |
| struct pfault_refbk { |
| u16 refdiagc; |
| u16 reffcode; |
| u16 refdwlen; |
| u16 refversn; |
| u64 refgaddr; |
| u64 refselmk; |
| u64 refcmpmk; |
| u64 reserved; |
| } __attribute__ ((packed, aligned(8))); |
| |
| int pfault_init(void) |
| { |
| struct pfault_refbk refbk = { |
| .refdiagc = 0x258, |
| .reffcode = 0, |
| .refdwlen = 5, |
| .refversn = 2, |
| .refgaddr = __LC_LPP, |
| .refselmk = 1ULL << 48, |
| .refcmpmk = 1ULL << 48, |
| .reserved = __PF_RES_FIELD }; |
| int rc; |
| |
| if (pfault_disable) |
| return -1; |
| diag_stat_inc(DIAG_STAT_X258); |
| asm volatile( |
| " diag %1,%0,0x258\n" |
| "0: j 2f\n" |
| "1: la %0,8\n" |
| "2:\n" |
| EX_TABLE(0b,1b) |
| : "=d" (rc) : "a" (&refbk), "m" (refbk) : "cc"); |
| return rc; |
| } |
| |
| void pfault_fini(void) |
| { |
| struct pfault_refbk refbk = { |
| .refdiagc = 0x258, |
| .reffcode = 1, |
| .refdwlen = 5, |
| .refversn = 2, |
| }; |
| |
| if (pfault_disable) |
| return; |
| diag_stat_inc(DIAG_STAT_X258); |
| asm volatile( |
| " diag %0,0,0x258\n" |
| "0:\n" |
| EX_TABLE(0b,0b) |
| : : "a" (&refbk), "m" (refbk) : "cc"); |
| } |
| |
| static DEFINE_SPINLOCK(pfault_lock); |
| static LIST_HEAD(pfault_list); |
| |
| static void pfault_interrupt(struct ext_code ext_code, |
| unsigned int param32, unsigned long param64) |
| { |
| struct task_struct *tsk; |
| __u16 subcode; |
| pid_t pid; |
| |
| /* |
| * Get the external interruption subcode & pfault |
| * initial/completion signal bit. VM stores this |
| * in the 'cpu address' field associated with the |
| * external interrupt. |
| */ |
| subcode = ext_code.subcode; |
| if ((subcode & 0xff00) != __SUBCODE_MASK) |
| return; |
| inc_irq_stat(IRQEXT_PFL); |
| /* Get the token (= pid of the affected task). */ |
| pid = param64 & LPP_PFAULT_PID_MASK; |
| rcu_read_lock(); |
| tsk = find_task_by_pid_ns(pid, &init_pid_ns); |
| if (tsk) |
| get_task_struct(tsk); |
| rcu_read_unlock(); |
| if (!tsk) |
| return; |
| spin_lock(&pfault_lock); |
| if (subcode & 0x0080) { |
| /* signal bit is set -> a page has been swapped in by VM */ |
| if (tsk->thread.pfault_wait == 1) { |
| /* Initial interrupt was faster than the completion |
| * interrupt. pfault_wait is valid. Set pfault_wait |
| * back to zero and wake up the process. This can |
| * safely be done because the task is still sleeping |
| * and can't produce new pfaults. */ |
| tsk->thread.pfault_wait = 0; |
| list_del(&tsk->thread.list); |
| wake_up_process(tsk); |
| put_task_struct(tsk); |
| } else { |
| /* Completion interrupt was faster than initial |
| * interrupt. Set pfault_wait to -1 so the initial |
| * interrupt doesn't put the task to sleep. |
| * If the task is not running, ignore the completion |
| * interrupt since it must be a leftover of a PFAULT |
| * CANCEL operation which didn't remove all pending |
| * completion interrupts. */ |
| if (tsk->state == TASK_RUNNING) |
| tsk->thread.pfault_wait = -1; |
| } |
| } else { |
| /* signal bit not set -> a real page is missing. */ |
| if (WARN_ON_ONCE(tsk != current)) |
| goto out; |
| if (tsk->thread.pfault_wait == 1) { |
| /* Already on the list with a reference: put to sleep */ |
| __set_task_state(tsk, TASK_UNINTERRUPTIBLE); |
| set_tsk_need_resched(tsk); |
| } else if (tsk->thread.pfault_wait == -1) { |
| /* Completion interrupt was faster than the initial |
| * interrupt (pfault_wait == -1). Set pfault_wait |
| * back to zero and exit. */ |
| tsk->thread.pfault_wait = 0; |
| } else { |
| /* Initial interrupt arrived before completion |
| * interrupt. Let the task sleep. |
| * An extra task reference is needed since a different |
| * cpu may set the task state to TASK_RUNNING again |
| * before the scheduler is reached. */ |
| get_task_struct(tsk); |
| tsk->thread.pfault_wait = 1; |
| list_add(&tsk->thread.list, &pfault_list); |
| __set_task_state(tsk, TASK_UNINTERRUPTIBLE); |
| set_tsk_need_resched(tsk); |
| } |
| } |
| out: |
| spin_unlock(&pfault_lock); |
| put_task_struct(tsk); |
| } |
| |
| static int pfault_cpu_notify(struct notifier_block *self, unsigned long action, |
| void *hcpu) |
| { |
| struct thread_struct *thread, *next; |
| struct task_struct *tsk; |
| |
| switch (action & ~CPU_TASKS_FROZEN) { |
| case CPU_DEAD: |
| spin_lock_irq(&pfault_lock); |
| list_for_each_entry_safe(thread, next, &pfault_list, list) { |
| thread->pfault_wait = 0; |
| list_del(&thread->list); |
| tsk = container_of(thread, struct task_struct, thread); |
| wake_up_process(tsk); |
| put_task_struct(tsk); |
| } |
| spin_unlock_irq(&pfault_lock); |
| break; |
| default: |
| break; |
| } |
| return NOTIFY_OK; |
| } |
| |
| static int __init pfault_irq_init(void) |
| { |
| int rc; |
| |
| rc = register_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt); |
| if (rc) |
| goto out_extint; |
| rc = pfault_init() == 0 ? 0 : -EOPNOTSUPP; |
| if (rc) |
| goto out_pfault; |
| irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL); |
| hotcpu_notifier(pfault_cpu_notify, 0); |
| return 0; |
| |
| out_pfault: |
| unregister_external_irq(EXT_IRQ_CP_SERVICE, pfault_interrupt); |
| out_extint: |
| pfault_disable = 1; |
| return rc; |
| } |
| early_initcall(pfault_irq_init); |
| |
| #endif /* CONFIG_PFAULT */ |