From b4edf06c8aaae30ef926bd6853df6e59a7579ee9 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 16 Jul 2020 14:05:36 -0400 Subject: [PATCH] sparc32: switch to generic extables Signed-off-by: Al Viro --- arch/sparc/include/asm/elf_64.h | 1 - .../include/asm/{extable_64.h => extable.h} | 4 +- arch/sparc/include/asm/uaccess.h | 3 + arch/sparc/include/asm/uaccess_32.h | 33 ------ arch/sparc/include/asm/uaccess_64.h | 1 - arch/sparc/kernel/unaligned_32.c | 10 +- arch/sparc/mm/Makefile | 2 +- arch/sparc/mm/extable.c | 107 ------------------ arch/sparc/mm/fault_32.c | 26 ++--- lib/extable.c | 5 - 10 files changed, 22 insertions(+), 170 deletions(-) rename arch/sparc/include/asm/{extable_64.h => extable.h} (92%) delete mode 100644 arch/sparc/mm/extable.c diff --git a/arch/sparc/include/asm/elf_64.h b/arch/sparc/include/asm/elf_64.h index 7e078bc73ef5..8fb09eec8c3e 100644 --- a/arch/sparc/include/asm/elf_64.h +++ b/arch/sparc/include/asm/elf_64.h @@ -8,7 +8,6 @@ #include #include -#include #include #include diff --git a/arch/sparc/include/asm/extable_64.h b/arch/sparc/include/asm/extable.h similarity index 92% rename from arch/sparc/include/asm/extable_64.h rename to arch/sparc/include/asm/extable.h index 5a0171907b7e..554a9dc376fc 100644 --- a/arch/sparc/include/asm/extable_64.h +++ b/arch/sparc/include/asm/extable.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ -#ifndef __ASM_EXTABLE64_H -#define __ASM_EXTABLE64_H +#ifndef __ASM_EXTABLE_H +#define __ASM_EXTABLE_H /* * The exception table consists of pairs of addresses: the first is the * address of an instruction that is allowed to fault, and the second is diff --git a/arch/sparc/include/asm/uaccess.h b/arch/sparc/include/asm/uaccess.h index dd85bc2c2cad..390094200fc4 100644 --- a/arch/sparc/include/asm/uaccess.h +++ b/arch/sparc/include/asm/uaccess.h @@ -1,6 +1,9 @@ /* SPDX-License-Identifier: GPL-2.0 */ #ifndef ___ASM_SPARC_UACCESS_H #define ___ASM_SPARC_UACCESS_H + +#include + #if defined(__sparc__) && defined(__arch64__) #include #else diff --git a/arch/sparc/include/asm/uaccess_32.h b/arch/sparc/include/asm/uaccess_32.h index 54a3ba742647..4a12346bb69c 100644 --- a/arch/sparc/include/asm/uaccess_32.h +++ b/arch/sparc/include/asm/uaccess_32.h @@ -13,9 +13,6 @@ #include -#define ARCH_HAS_SORT_EXTABLE -#define ARCH_HAS_SEARCH_EXTABLE - /* Sparc is not segmented, however we need to be able to fool access_ok() * when doing system calls from kernel mode legitimately. * @@ -40,36 +37,6 @@ #define __access_ok(addr, size) (__user_ok((addr) & get_fs().seg, (size))) #define access_ok(addr, size) __access_ok((unsigned long)(addr), size) -/* - * The exception table consists of pairs of addresses: the first is the - * address of an instruction that is allowed to fault, and the second is - * the address at which the program should continue. No registers are - * modified, so it is entirely up to the continuation code to figure out - * what to do. - * - * All the routines below use bits of fixup code that are out of line - * with the main instruction path. This means when everything is well, - * we don't even have to jump over them. Further, they do not intrude - * on our cache or tlb entries. - * - * There is a special way how to put a range of potentially faulting - * insns (like twenty ldd/std's with now intervening other instructions) - * You specify address of first in insn and 0 in fixup and in the next - * exception_table_entry you specify last potentially faulting insn + 1 - * and in fixup the routine which should handle the fault. - * That fixup code will get - * (faulting_insn_address - first_insn_in_the_range_address)/4 - * in %g2 (ie. index of the faulting instruction in the range). - */ - -struct exception_table_entry -{ - unsigned long insn, fixup; -}; - -/* Returns 0 if exception not found and fixup otherwise. */ -unsigned long search_extables_range(unsigned long addr, unsigned long *g2); - /* Uh, these should become the main single-value transfer routines.. * They automatically use the right size if we just have the right * pointer type.. diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h index 698cf69f74e9..30eb4c6414d1 100644 --- a/arch/sparc/include/asm/uaccess_64.h +++ b/arch/sparc/include/asm/uaccess_64.h @@ -10,7 +10,6 @@ #include #include #include -#include #include diff --git a/arch/sparc/kernel/unaligned_32.c b/arch/sparc/kernel/unaligned_32.c index 83db94c0b431..1d7c3eaabdd4 100644 --- a/arch/sparc/kernel/unaligned_32.c +++ b/arch/sparc/kernel/unaligned_32.c @@ -16,6 +16,7 @@ #include #include #include +#include #include @@ -213,10 +214,10 @@ static inline int ok_for_kernel(unsigned int insn) static void kernel_mna_trap_fault(struct pt_regs *regs, unsigned int insn) { - unsigned long g2 = regs->u_regs [UREG_G2]; - unsigned long fixup = search_extables_range(regs->pc, &g2); + const struct exception_table_entry *entry; - if (!fixup) { + entry = search_exception_tables(regs->pc); + if (!entry) { unsigned long address = compute_effective_address(regs, insn); if(address < PAGE_SIZE) { printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference in mna handler"); @@ -232,9 +233,8 @@ static void kernel_mna_trap_fault(struct pt_regs *regs, unsigned int insn) die_if_kernel("Oops", regs); /* Not reached */ } - regs->pc = fixup; + regs->pc = entry->fixup; regs->npc = regs->pc + 4; - regs->u_regs [UREG_G2] = g2; } asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn) diff --git a/arch/sparc/mm/Makefile b/arch/sparc/mm/Makefile index 68db1f859b02..871354aa3c00 100644 --- a/arch/sparc/mm/Makefile +++ b/arch/sparc/mm/Makefile @@ -8,7 +8,7 @@ ccflags-y := -Werror obj-$(CONFIG_SPARC64) += ultra.o tlb.o tsb.o obj-y += fault_$(BITS).o obj-y += init_$(BITS).o -obj-$(CONFIG_SPARC32) += extable.o srmmu.o iommu.o io-unit.o +obj-$(CONFIG_SPARC32) += srmmu.o iommu.o io-unit.o obj-$(CONFIG_SPARC32) += srmmu_access.o obj-$(CONFIG_SPARC32) += hypersparc.o viking.o tsunami.o swift.o obj-$(CONFIG_SPARC32) += leon_mm.o diff --git a/arch/sparc/mm/extable.c b/arch/sparc/mm/extable.c deleted file mode 100644 index 241b40641873..000000000000 --- a/arch/sparc/mm/extable.c +++ /dev/null @@ -1,107 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * linux/arch/sparc/mm/extable.c - */ - -#include -#include -#include - -void sort_extable(struct exception_table_entry *start, - struct exception_table_entry *finish) -{ -} - -/* Caller knows they are in a range if ret->fixup == 0 */ -const struct exception_table_entry * -search_extable(const struct exception_table_entry *base, - const size_t num, - unsigned long value) -{ - int i; - - /* Single insn entries are encoded as: - * word 1: insn address - * word 2: fixup code address - * - * Range entries are encoded as: - * word 1: first insn address - * word 2: 0 - * word 3: last insn address + 4 bytes - * word 4: fixup code address - * - * Deleted entries are encoded as: - * word 1: unused - * word 2: -1 - * - * See asm/uaccess.h for more details. - */ - - /* 1. Try to find an exact match. */ - for (i = 0; i < num; i++) { - if (base[i].fixup == 0) { - /* A range entry, skip both parts. */ - i++; - continue; - } - - /* A deleted entry; see trim_init_extable */ - if (base[i].fixup == -1) - continue; - - if (base[i].insn == value) - return &base[i]; - } - - /* 2. Try to find a range match. */ - for (i = 0; i < (num - 1); i++) { - if (base[i].fixup) - continue; - - if (base[i].insn <= value && base[i + 1].insn > value) - return &base[i]; - - i++; - } - - return NULL; -} - -#ifdef CONFIG_MODULES -/* We could memmove them around; easier to mark the trimmed ones. */ -void trim_init_extable(struct module *m) -{ - unsigned int i; - bool range; - - for (i = 0; i < m->num_exentries; i += range ? 2 : 1) { - range = m->extable[i].fixup == 0; - - if (within_module_init(m->extable[i].insn, m)) { - m->extable[i].fixup = -1; - if (range) - m->extable[i+1].fixup = -1; - } - if (range) - i++; - } -} -#endif /* CONFIG_MODULES */ - -/* Special extable search, which handles ranges. Returns fixup */ -unsigned long search_extables_range(unsigned long addr, unsigned long *g2) -{ - const struct exception_table_entry *entry; - - entry = search_exception_tables(addr); - if (!entry) - return 0; - - /* Inside range? Fix g2 and return correct fixup */ - if (!entry->fixup) { - *g2 = (addr - entry->insn) / 4; - return (entry + 1)->fixup; - } - - return entry->fixup; -} diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c index 290869fd6b6a..de2031c2b2d7 100644 --- a/arch/sparc/mm/fault_32.c +++ b/arch/sparc/mm/fault_32.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include @@ -114,8 +115,6 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write, struct vm_area_struct *vma; struct task_struct *tsk = current; struct mm_struct *mm = tsk->mm; - unsigned int fixup; - unsigned long g2; int from_user = !(regs->psr & PSR_PS); int code; vm_fault_t fault; @@ -233,22 +232,19 @@ bad_area_nosemaphore: /* Is this in ex_table? */ no_context: - g2 = regs->u_regs[UREG_G2]; if (!from_user) { - fixup = search_extables_range(regs->pc, &g2); - /* Values below 10 are reserved for other things */ - if (fixup > 10) { + const struct exception_table_entry *entry; + + entry = search_exception_tables(regs->pc); #ifdef DEBUG_EXCEPTIONS - printk("Exception: PC<%08lx> faddr<%08lx>\n", - regs->pc, address); - printk("EX_TABLE: insn<%08lx> fixup<%08x> g2<%08lx>\n", - regs->pc, fixup, g2); + printk("Exception: PC<%08lx> faddr<%08lx>\n", + regs->pc, address); + printk("EX_TABLE: insn<%08lx> fixup<%08x>\n", + regs->pc, entry->fixup); #endif - regs->u_regs[UREG_G2] = g2; - regs->pc = fixup; - regs->npc = regs->pc + 4; - return; - } + regs->pc = entry->fixup; + regs->npc = regs->pc + 4; + return; } unhandled_fault(address, tsk, regs); diff --git a/lib/extable.c b/lib/extable.c index c3e59caf7ffa..9c9f40bd2b3d 100644 --- a/lib/extable.c +++ b/lib/extable.c @@ -21,7 +21,6 @@ static inline unsigned long ex_to_insn(const struct exception_table_entry *x) } #endif -#ifndef ARCH_HAS_SORT_EXTABLE #ifndef ARCH_HAS_RELATIVE_EXTABLE #define swap_ex NULL #else @@ -88,9 +87,6 @@ void trim_init_extable(struct module *m) m->num_exentries--; } #endif /* CONFIG_MODULES */ -#endif /* !ARCH_HAS_SORT_EXTABLE */ - -#ifndef ARCH_HAS_SEARCH_EXTABLE static int cmp_ex_search(const void *key, const void *elt) { @@ -120,4 +116,3 @@ search_extable(const struct exception_table_entry *base, return bsearch(&value, base, num, sizeof(struct exception_table_entry), cmp_ex_search); } -#endif