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authorMike Rapoport <rppt@linux.ibm.com>2020-06-10 09:45:20 +0300
committerMike Rapoport <rppt@linux.ibm.com>2020-07-01 12:09:13 +0300
commitfb37409a01b011a664347702f44dbf13fa7c7486 (patch)
treef9422acc3b91dd0df2721eaca9209e867fe10eb9 /arch/unicore32/mm/fault.c
parent9ebcfadb0610322ac537dd7aa5d9cbc2b2894c68 (diff)
downloadlinux-fb37409a01b011a664347702f44dbf13fa7c7486.tar.bz2
arch: remove unicore32 port
The unicore32 port do not seem maintained for a long time now, there is no upstream toolchain that can create unicore32 binaries and all the links to prebuilt toolchains for unicore32 are dead. Even compilers that were available are not supported by the kernel anymore. Guenter Roeck says: I have stopped building unicore32 images since v4.19 since there is no available compiler that is still supported by the kernel. I am surprised that support for it has not been removed from the kernel. Remove unicore32 port. Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'arch/unicore32/mm/fault.c')
-rw-r--r--arch/unicore32/mm/fault.c481
1 files changed, 0 insertions, 481 deletions
diff --git a/arch/unicore32/mm/fault.c b/arch/unicore32/mm/fault.c
deleted file mode 100644
index 7654bddde133..000000000000
--- a/arch/unicore32/mm/fault.c
+++ /dev/null
@@ -1,481 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * linux/arch/unicore32/mm/fault.c
- *
- * Code specific to PKUnity SoC and UniCore ISA
- *
- * Copyright (C) 2001-2010 GUAN Xue-tao
- */
-#include <linux/extable.h>
-#include <linux/signal.h>
-#include <linux/mm.h>
-#include <linux/hardirq.h>
-#include <linux/init.h>
-#include <linux/kprobes.h>
-#include <linux/uaccess.h>
-#include <linux/page-flags.h>
-#include <linux/sched/signal.h>
-#include <linux/io.h>
-
-#include <asm/tlbflush.h>
-
-/*
- * Fault status register encodings. We steal bit 31 for our own purposes.
- */
-#define FSR_LNX_PF (1 << 31)
-
-static inline int fsr_fs(unsigned int fsr)
-{
- /* xyabcde will be abcde+xy */
- return (fsr & 31) + ((fsr & (3 << 5)) >> 5);
-}
-
-/*
- * This is useful to dump out the page tables associated with
- * 'addr' in mm 'mm'.
- */
-void show_pte(struct mm_struct *mm, unsigned long addr)
-{
- pgd_t *pgd;
-
- if (!mm)
- mm = &init_mm;
-
- printk(KERN_ALERT "pgd = %p\n", mm->pgd);
- pgd = pgd_offset(mm, addr);
- printk(KERN_ALERT "[%08lx] *pgd=%08lx", addr, pgd_val(*pgd));
-
- do {
- pmd_t *pmd;
- pte_t *pte;
-
- if (pgd_none(*pgd))
- break;
-
- if (pgd_bad(*pgd)) {
- printk("(bad)");
- break;
- }
-
- pmd = pmd_offset((pud_t *) pgd, addr);
- if (PTRS_PER_PMD != 1)
- printk(", *pmd=%08lx", pmd_val(*pmd));
-
- if (pmd_none(*pmd))
- break;
-
- if (pmd_bad(*pmd)) {
- printk("(bad)");
- break;
- }
-
- /* We must not map this if we have highmem enabled */
- if (PageHighMem(pfn_to_page(pmd_val(*pmd) >> PAGE_SHIFT)))
- break;
-
- pte = pte_offset_map(pmd, addr);
- printk(", *pte=%08lx", pte_val(*pte));
- pte_unmap(pte);
- } while (0);
-
- printk("\n");
-}
-
-/*
- * Oops. The kernel tried to access some page that wasn't present.
- */
-static void __do_kernel_fault(struct mm_struct *mm, unsigned long addr,
- unsigned int fsr, struct pt_regs *regs)
-{
- /*
- * Are we prepared to handle this kernel fault?
- */
- if (fixup_exception(regs))
- return;
-
- /*
- * No handler, we'll have to terminate things with extreme prejudice.
- */
- bust_spinlocks(1);
- printk(KERN_ALERT
- "Unable to handle kernel %s at virtual address %08lx\n",
- (addr < PAGE_SIZE) ? "NULL pointer dereference" :
- "paging request", addr);
-
- show_pte(mm, addr);
- die("Oops", regs, fsr);
- bust_spinlocks(0);
- do_exit(SIGKILL);
-}
-
-/*
- * Something tried to access memory that isn't in our memory map..
- * User mode accesses just cause a SIGSEGV
- */
-static void __do_user_fault(unsigned long addr, unsigned int fsr,
- unsigned int sig, int code, struct pt_regs *regs)
-{
- struct task_struct *tsk = current;
-
- tsk->thread.address = addr;
- tsk->thread.error_code = fsr;
- tsk->thread.trap_no = 14;
- force_sig_fault(sig, code, (void __user *)addr);
-}
-
-void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
-{
- struct task_struct *tsk = current;
- struct mm_struct *mm = tsk->active_mm;
-
- /*
- * If we are in kernel mode at this point, we
- * have no context to handle this fault with.
- */
- if (user_mode(regs))
- __do_user_fault(addr, fsr, SIGSEGV, SEGV_MAPERR, regs);
- else
- __do_kernel_fault(mm, addr, fsr, regs);
-}
-
-#define VM_FAULT_BADMAP 0x010000
-#define VM_FAULT_BADACCESS 0x020000
-
-/*
- * Check that the permissions on the VMA allow for the fault which occurred.
- * If we encountered a write fault, we must have write permission, otherwise
- * we allow any permission.
- */
-static inline bool access_error(unsigned int fsr, struct vm_area_struct *vma)
-{
- unsigned int mask = VM_ACCESS_FLAGS;
-
- if (!(fsr ^ 0x12)) /* write? */
- mask = VM_WRITE;
- if (fsr & FSR_LNX_PF)
- mask = VM_EXEC;
-
- return vma->vm_flags & mask ? false : true;
-}
-
-static vm_fault_t __do_pf(struct mm_struct *mm, unsigned long addr,
- unsigned int fsr, unsigned int flags, struct task_struct *tsk)
-{
- struct vm_area_struct *vma;
- vm_fault_t fault;
-
- vma = find_vma(mm, addr);
- fault = VM_FAULT_BADMAP;
- if (unlikely(!vma))
- goto out;
- if (unlikely(vma->vm_start > addr))
- goto check_stack;
-
- /*
- * Ok, we have a good vm_area for this
- * memory access, so we can handle it.
- */
-good_area:
- if (access_error(fsr, vma)) {
- fault = VM_FAULT_BADACCESS;
- goto out;
- }
-
- /*
- * 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(vma, addr & PAGE_MASK, flags);
- return fault;
-
-check_stack:
- if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr))
- goto good_area;
-out:
- return fault;
-}
-
-static int do_pf(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
-{
- struct task_struct *tsk;
- struct mm_struct *mm;
- int sig, code;
- vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_DEFAULT;
-
- tsk = current;
- mm = tsk->mm;
-
- /*
- * If we're in an interrupt or have no user
- * context, we must not take the fault..
- */
- if (faulthandler_disabled() || !mm)
- goto no_context;
-
- if (user_mode(regs))
- flags |= FAULT_FLAG_USER;
- if (!(fsr ^ 0x12))
- flags |= FAULT_FLAG_WRITE;
-
- /*
- * As per x86, we may deadlock here. However, since the kernel only
- * validly references user space from well defined areas of the code,
- * we can bug out early if this is from code which shouldn't.
- */
- if (!mmap_read_trylock(mm)) {
- if (!user_mode(regs)
- && !search_exception_tables(regs->UCreg_pc))
- goto no_context;
-retry:
- mmap_read_lock(mm);
- } else {
- /*
- * The above down_read_trylock() might have succeeded in
- * which case, we'll have missed the might_sleep() from
- * down_read()
- */
- might_sleep();
-#ifdef CONFIG_DEBUG_VM
- if (!user_mode(regs) &&
- !search_exception_tables(regs->UCreg_pc))
- goto no_context;
-#endif
- }
-
- fault = __do_pf(mm, addr, fsr, flags, tsk);
-
- /* If we need to retry but a fatal signal is pending, handle the
- * signal first. We do not need to release the mmap_lock because
- * it would already be released in __lock_page_or_retry in
- * mm/filemap.c. */
- if (fault_signal_pending(fault, regs))
- return 0;
-
- if (!(fault & VM_FAULT_ERROR) && (flags & FAULT_FLAG_ALLOW_RETRY)) {
- if (fault & VM_FAULT_MAJOR)
- tsk->maj_flt++;
- else
- tsk->min_flt++;
- if (fault & VM_FAULT_RETRY) {
- flags |= FAULT_FLAG_TRIED;
- goto retry;
- }
- }
-
- mmap_read_unlock(mm);
-
- /*
- * Handle the "normal" case first - VM_FAULT_MAJOR
- */
- if (likely(!(fault &
- (VM_FAULT_ERROR | VM_FAULT_BADMAP | VM_FAULT_BADACCESS))))
- return 0;
-
- /*
- * If we are in kernel mode at this point, we
- * have no context to handle this fault with.
- */
- if (!user_mode(regs))
- goto no_context;
-
- if (fault & VM_FAULT_OOM) {
- /*
- * We ran out of memory, call the OOM killer, and return to
- * userspace (which will retry the fault, or kill us if we
- * got oom-killed)
- */
- pagefault_out_of_memory();
- return 0;
- }
-
- if (fault & VM_FAULT_SIGBUS) {
- /*
- * We had some memory, but were unable to
- * successfully fix up this page fault.
- */
- sig = SIGBUS;
- code = BUS_ADRERR;
- } else {
- /*
- * Something tried to access memory that
- * isn't in our memory map..
- */
- sig = SIGSEGV;
- code = fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR;
- }
-
- __do_user_fault(addr, fsr, sig, code, regs);
- return 0;
-
-no_context:
- __do_kernel_fault(mm, addr, fsr, regs);
- return 0;
-}
-
-/*
- * First Level Translation Fault Handler
- *
- * We enter here because the first level page table doesn't contain
- * a valid entry for the address.
- *
- * If the address is in kernel space (>= TASK_SIZE), then we are
- * probably faulting in the vmalloc() area.
- *
- * If the init_task's first level page tables contains the relevant
- * entry, we copy the it to this task. If not, we send the process
- * a signal, fixup the exception, or oops the kernel.
- *
- * 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.
- */
-static int do_ifault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
-{
- unsigned int index;
- pgd_t *pgd, *pgd_k;
- pmd_t *pmd, *pmd_k;
-
- if (addr < TASK_SIZE)
- return do_pf(addr, fsr, regs);
-
- if (user_mode(regs))
- goto bad_area;
-
- index = pgd_index(addr);
-
- pgd = cpu_get_pgd() + index;
- pgd_k = init_mm.pgd + index;
-
- if (pgd_none(*pgd_k))
- goto bad_area;
-
- pmd_k = pmd_offset((pud_t *) pgd_k, addr);
- pmd = pmd_offset((pud_t *) pgd, addr);
-
- if (pmd_none(*pmd_k))
- goto bad_area;
-
- set_pmd(pmd, *pmd_k);
- flush_pmd_entry(pmd);
- return 0;
-
-bad_area:
- do_bad_area(addr, fsr, regs);
- return 0;
-}
-
-/*
- * This abort handler always returns "fault".
- */
-static int do_bad(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
-{
- return 1;
-}
-
-static int do_good(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
-{
- unsigned int res1, res2;
-
- printk("dabt exception but no error!\n");
-
- __asm__ __volatile__(
- "mff %0,f0\n"
- "mff %1,f1\n"
- : "=r"(res1), "=r"(res2)
- :
- : "memory");
-
- printk(KERN_EMERG "r0 :%08x r1 :%08x\n", res1, res2);
- panic("shut up\n");
- return 0;
-}
-
-static struct fsr_info {
- int (*fn) (unsigned long addr, unsigned int fsr, struct pt_regs *regs);
- int sig;
- int code;
- const char *name;
-} fsr_info[] = {
- /*
- * The following are the standard Unicore-I and UniCore-II aborts.
- */
- { do_good, SIGBUS, 0, "no error" },
- { do_bad, SIGBUS, BUS_ADRALN, "alignment exception" },
- { do_bad, SIGBUS, BUS_OBJERR, "external exception" },
- { do_bad, SIGBUS, 0, "burst operation" },
- { do_bad, SIGBUS, 0, "unknown 00100" },
- { do_ifault, SIGSEGV, SEGV_MAPERR, "2nd level pt non-exist"},
- { do_bad, SIGBUS, 0, "2nd lvl large pt non-exist" },
- { do_bad, SIGBUS, 0, "invalid pte" },
- { do_pf, SIGSEGV, SEGV_MAPERR, "page miss" },
- { do_bad, SIGBUS, 0, "middle page miss" },
- { do_bad, SIGBUS, 0, "large page miss" },
- { do_pf, SIGSEGV, SEGV_MAPERR, "super page (section) miss" },
- { do_bad, SIGBUS, 0, "unknown 01100" },
- { do_bad, SIGBUS, 0, "unknown 01101" },
- { do_bad, SIGBUS, 0, "unknown 01110" },
- { do_bad, SIGBUS, 0, "unknown 01111" },
- { do_bad, SIGBUS, 0, "addr: up 3G or IO" },
- { do_pf, SIGSEGV, SEGV_ACCERR, "read unreadable addr" },
- { do_pf, SIGSEGV, SEGV_ACCERR, "write unwriteable addr"},
- { do_pf, SIGSEGV, SEGV_ACCERR, "exec unexecutable addr"},
- { do_bad, SIGBUS, 0, "unknown 10100" },
- { do_bad, SIGBUS, 0, "unknown 10101" },
- { do_bad, SIGBUS, 0, "unknown 10110" },
- { do_bad, SIGBUS, 0, "unknown 10111" },
- { do_bad, SIGBUS, 0, "unknown 11000" },
- { do_bad, SIGBUS, 0, "unknown 11001" },
- { do_bad, SIGBUS, 0, "unknown 11010" },
- { do_bad, SIGBUS, 0, "unknown 11011" },
- { do_bad, SIGBUS, 0, "unknown 11100" },
- { do_bad, SIGBUS, 0, "unknown 11101" },
- { do_bad, SIGBUS, 0, "unknown 11110" },
- { do_bad, SIGBUS, 0, "unknown 11111" }
-};
-
-void __init hook_fault_code(int nr,
- int (*fn) (unsigned long, unsigned int, struct pt_regs *),
- int sig, int code, const char *name)
-{
- if (nr < 0 || nr >= ARRAY_SIZE(fsr_info))
- BUG();
-
- fsr_info[nr].fn = fn;
- fsr_info[nr].sig = sig;
- fsr_info[nr].code = code;
- fsr_info[nr].name = name;
-}
-
-/*
- * Dispatch a data abort to the relevant handler.
- */
-asmlinkage void do_DataAbort(unsigned long addr, unsigned int fsr,
- struct pt_regs *regs)
-{
- const struct fsr_info *inf = fsr_info + fsr_fs(fsr);
-
- if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs))
- return;
-
- printk(KERN_ALERT "Unhandled fault: %s (0x%03x) at 0x%08lx\n",
- inf->name, fsr, addr);
-
- uc32_notify_die("", regs, inf->sig, inf->code, (void __user *)addr,
- fsr, 0);
-}
-
-asmlinkage void do_PrefetchAbort(unsigned long addr,
- unsigned int ifsr, struct pt_regs *regs)
-{
- const struct fsr_info *inf = fsr_info + fsr_fs(ifsr);
-
- if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs))
- return;
-
- printk(KERN_ALERT "Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n",
- inf->name, ifsr, addr);
-
- uc32_notify_die("", regs, inf->sig, inf->code, (void __user *)addr,
- ifsr, 0);
-}