From 9fde0348640252c79d462c4d29a09a14e8741f5c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 16 Sep 2021 09:04:05 +0200 Subject: m68k: Remove set_fs() Add a m68k-only set_fc helper to set the SFC and DFC registers for the few places that need to override it for special MM operations, but disconnect that from the deprecated kernel-wide set_fs() API. Note that the SFC/DFC registers are context switched, so there is no need to disable preemption. Partially based on an earlier patch from Linus Torvalds . Signed-off-by: Christoph Hellwig Reviewed-by: Michael Schmitz Tested-by: Michael Schmitz Link: https://lore.kernel.org/r/20210916070405.52750-7-hch@lst.de Signed-off-by: Geert Uytterhoeven --- arch/m68k/68000/entry.S | 1 - arch/m68k/Kconfig | 1 - arch/m68k/coldfire/entry.S | 1 - arch/m68k/include/asm/processor.h | 31 +++++++++++++++++-- arch/m68k/include/asm/segment.h | 59 ------------------------------------- arch/m68k/include/asm/thread_info.h | 3 -- arch/m68k/include/asm/tlbflush.h | 11 ++----- arch/m68k/include/asm/uaccess.h | 4 --- arch/m68k/kernel/asm-offsets.c | 2 +- arch/m68k/kernel/entry.S | 5 ++-- arch/m68k/kernel/process.c | 4 +-- arch/m68k/kernel/traps.c | 13 +++----- arch/m68k/mac/misc.c | 1 - arch/m68k/mm/cache.c | 6 ++-- arch/m68k/mm/init.c | 6 ---- arch/m68k/mm/kmap.c | 1 - arch/m68k/mm/memory.c | 1 - arch/m68k/mm/motorola.c | 2 +- arch/m68k/sun3/config.c | 3 +- arch/m68k/sun3/mmu_emu.c | 6 ++-- arch/m68k/sun3/sun3ints.c | 1 - arch/m68k/sun3x/prom.c | 1 - 22 files changed, 46 insertions(+), 117 deletions(-) delete mode 100644 arch/m68k/include/asm/segment.h (limited to 'arch/m68k') diff --git a/arch/m68k/68000/entry.S b/arch/m68k/68000/entry.S index cce465e850fe..997b54933015 100644 --- a/arch/m68k/68000/entry.S +++ b/arch/m68k/68000/entry.S @@ -15,7 +15,6 @@ #include #include #include -#include #include #include #include diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 774c35f47eea..0b50da08a9c5 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -29,7 +29,6 @@ config M68K select NO_DMA if !MMU && !COLDFIRE select OLD_SIGACTION select OLD_SIGSUSPEND3 - select SET_FS select UACCESS_MEMCPY if !MMU select VIRT_TO_BUS select ZONE_DMA diff --git a/arch/m68k/coldfire/entry.S b/arch/m68k/coldfire/entry.S index 68adb7b5b296..9f337c70243a 100644 --- a/arch/m68k/coldfire/entry.S +++ b/arch/m68k/coldfire/entry.S @@ -31,7 +31,6 @@ #include #include #include -#include #include #include diff --git a/arch/m68k/include/asm/processor.h b/arch/m68k/include/asm/processor.h index 3750819ac5a1..f4d82c619a5c 100644 --- a/arch/m68k/include/asm/processor.h +++ b/arch/m68k/include/asm/processor.h @@ -9,7 +9,6 @@ #define __ASM_M68K_PROCESSOR_H #include -#include #include #include @@ -75,11 +74,37 @@ static inline void wrusp(unsigned long usp) #define TASK_UNMAPPED_BASE 0 #endif +/* Address spaces (or Function Codes in Motorola lingo) */ +#define USER_DATA 1 +#define USER_PROGRAM 2 +#define SUPER_DATA 5 +#define SUPER_PROGRAM 6 +#define CPU_SPACE 7 + +#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES +/* + * Set the SFC/DFC registers for special MM operations. For most normal + * operation these remain set to USER_DATA for the uaccess routines. + */ +static inline void set_fc(unsigned long val) +{ + WARN_ON_ONCE(in_interrupt()); + + __asm__ __volatile__ ("movec %0,%/sfc\n\t" + "movec %0,%/dfc\n\t" + : /* no outputs */ : "r" (val) : "memory"); +} +#else +static inline void set_fc(unsigned long val) +{ +} +#endif /* CONFIG_CPU_HAS_ADDRESS_SPACES */ + struct thread_struct { unsigned long ksp; /* kernel stack pointer */ unsigned long usp; /* user stack pointer */ unsigned short sr; /* saved status register */ - unsigned short fs; /* saved fs (sfc, dfc) */ + unsigned short fc; /* saved fc (sfc, dfc) */ unsigned long crp[2]; /* cpu root pointer */ unsigned long esp0; /* points to SR of stack frame */ unsigned long faddr; /* info about last fault */ @@ -92,7 +117,7 @@ struct thread_struct { #define INIT_THREAD { \ .ksp = sizeof(init_stack) + (unsigned long) init_stack, \ .sr = PS_S, \ - .fs = __KERNEL_DS, \ + .fc = USER_DATA, \ } /* diff --git a/arch/m68k/include/asm/segment.h b/arch/m68k/include/asm/segment.h deleted file mode 100644 index 2b5e68a71ef7..000000000000 --- a/arch/m68k/include/asm/segment.h +++ /dev/null @@ -1,59 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _M68K_SEGMENT_H -#define _M68K_SEGMENT_H - -/* define constants */ -/* Address spaces (FC0-FC2) */ -#define USER_DATA (1) -#ifndef __USER_DS -#define __USER_DS (USER_DATA) -#endif -#define USER_PROGRAM (2) -#define SUPER_DATA (5) -#ifndef __KERNEL_DS -#define __KERNEL_DS (SUPER_DATA) -#endif -#define SUPER_PROGRAM (6) -#define CPU_SPACE (7) - -#ifndef __ASSEMBLY__ - -typedef struct { - unsigned long seg; -} mm_segment_t; - -#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) - -#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES -/* - * Get/set the SFC/DFC registers for MOVES instructions - */ -#define USER_DS MAKE_MM_SEG(__USER_DS) -#define KERNEL_DS MAKE_MM_SEG(__KERNEL_DS) - -static inline mm_segment_t get_fs(void) -{ - mm_segment_t _v; - __asm__ ("movec %/dfc,%0":"=r" (_v.seg):); - return _v; -} - -static inline void set_fs(mm_segment_t val) -{ - __asm__ __volatile__ ("movec %0,%/sfc\n\t" - "movec %0,%/dfc\n\t" - : /* no outputs */ : "r" (val.seg) : "memory"); -} - -#else -#define USER_DS MAKE_MM_SEG(TASK_SIZE) -#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) -#define get_fs() (current_thread_info()->addr_limit) -#define set_fs(x) (current_thread_info()->addr_limit = (x)) -#endif - -#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg) - -#endif /* __ASSEMBLY__ */ - -#endif /* _M68K_SEGMENT_H */ diff --git a/arch/m68k/include/asm/thread_info.h b/arch/m68k/include/asm/thread_info.h index 15a757073fa5..c952658ba792 100644 --- a/arch/m68k/include/asm/thread_info.h +++ b/arch/m68k/include/asm/thread_info.h @@ -4,7 +4,6 @@ #include #include -#include /* * On machines with 4k pages we default to an 8k thread size, though we @@ -27,7 +26,6 @@ struct thread_info { struct task_struct *task; /* main task structure */ unsigned long flags; - mm_segment_t addr_limit; /* thread address space */ int preempt_count; /* 0 => preemptable, <0 => BUG */ __u32 cpu; /* should always be 0 on m68k */ unsigned long tp_value; /* thread pointer */ @@ -37,7 +35,6 @@ struct thread_info { #define INIT_THREAD_INFO(tsk) \ { \ .task = &tsk, \ - .addr_limit = KERNEL_DS, \ .preempt_count = INIT_PREEMPT_COUNT, \ } diff --git a/arch/m68k/include/asm/tlbflush.h b/arch/m68k/include/asm/tlbflush.h index a6318ccd308f..b882e2f4f551 100644 --- a/arch/m68k/include/asm/tlbflush.h +++ b/arch/m68k/include/asm/tlbflush.h @@ -13,13 +13,12 @@ static inline void flush_tlb_kernel_page(void *addr) if (CPU_IS_COLDFIRE) { mmu_write(MMUOR, MMUOR_CNL); } else if (CPU_IS_040_OR_060) { - mm_segment_t old_fs = get_fs(); - set_fs(KERNEL_DS); + set_fc(SUPER_DATA); __asm__ __volatile__(".chip 68040\n\t" "pflush (%0)\n\t" ".chip 68k" : : "a" (addr)); - set_fs(old_fs); + set_fc(USER_DATA); } else if (CPU_IS_020_OR_030) __asm__ __volatile__("pflush #4,#4,(%0)" : : "a" (addr)); } @@ -84,12 +83,8 @@ static inline void flush_tlb_mm(struct mm_struct *mm) static inline void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) { - if (vma->vm_mm == current->active_mm) { - mm_segment_t old_fs = force_uaccess_begin(); - + if (vma->vm_mm == current->active_mm) __flush_tlb_one(addr); - force_uaccess_end(old_fs); - } } static inline void flush_tlb_range(struct vm_area_struct *vma, diff --git a/arch/m68k/include/asm/uaccess.h b/arch/m68k/include/asm/uaccess.h index 65581a7874d4..ba670523885c 100644 --- a/arch/m68k/include/asm/uaccess.h +++ b/arch/m68k/include/asm/uaccess.h @@ -9,7 +9,6 @@ */ #include #include -#include #include /* We let the MMU do all checking */ @@ -451,9 +450,6 @@ do { \ goto err_label; \ } while (0) -#define user_addr_max() \ - (uaccess_kernel() ? ~0UL : TASK_SIZE) - extern long strncpy_from_user(char *dst, const char __user *src, long count); extern __must_check long strnlen_user(const char __user *str, long n); diff --git a/arch/m68k/kernel/asm-offsets.c b/arch/m68k/kernel/asm-offsets.c index ccea355052ef..906d73230537 100644 --- a/arch/m68k/kernel/asm-offsets.c +++ b/arch/m68k/kernel/asm-offsets.c @@ -31,7 +31,7 @@ int main(void) DEFINE(THREAD_KSP, offsetof(struct thread_struct, ksp)); DEFINE(THREAD_USP, offsetof(struct thread_struct, usp)); DEFINE(THREAD_SR, offsetof(struct thread_struct, sr)); - DEFINE(THREAD_FS, offsetof(struct thread_struct, fs)); + DEFINE(THREAD_FC, offsetof(struct thread_struct, fc)); DEFINE(THREAD_CRP, offsetof(struct thread_struct, crp)); DEFINE(THREAD_ESP0, offsetof(struct thread_struct, esp0)); DEFINE(THREAD_FPREG, offsetof(struct thread_struct, fp)); diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S index 8fa9822b5922..9434fca68de5 100644 --- a/arch/m68k/kernel/entry.S +++ b/arch/m68k/kernel/entry.S @@ -36,7 +36,6 @@ #include #include #include -#include #include #include #include @@ -337,7 +336,7 @@ resume: /* save fs (sfc,%dfc) (may be pointing to kernel memory) */ movec %sfc,%d0 - movew %d0,%a0@(TASK_THREAD+THREAD_FS) + movew %d0,%a0@(TASK_THREAD+THREAD_FC) /* save usp */ /* it is better to use a movel here instead of a movew 8*) */ @@ -423,7 +422,7 @@ resume: movel %a0,%usp /* restore fs (sfc,%dfc) */ - movew %a1@(TASK_THREAD+THREAD_FS),%a0 + movew %a1@(TASK_THREAD+THREAD_FC),%a0 movec %a0,%sfc movec %a0,%dfc diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c index db49f9091711..1ab692b952cd 100644 --- a/arch/m68k/kernel/process.c +++ b/arch/m68k/kernel/process.c @@ -92,7 +92,7 @@ void show_regs(struct pt_regs * regs) void flush_thread(void) { - current->thread.fs = __USER_DS; + current->thread.fc = USER_DATA; #ifdef CONFIG_FPU if (!FPU_IS_EMU) { unsigned long zero = 0; @@ -155,7 +155,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg, * Must save the current SFC/DFC value, NOT the value when * the parent was last descheduled - RGH 10-08-96 */ - p->thread.fs = get_fs().seg; + p->thread.fc = USER_DATA; if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) { /* kernel thread */ diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c index 5b19fcdcd69e..9718ce94cc84 100644 --- a/arch/m68k/kernel/traps.c +++ b/arch/m68k/kernel/traps.c @@ -181,9 +181,8 @@ static inline void access_error060 (struct frame *fp) static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs) { unsigned long mmusr; - mm_segment_t old_fs = get_fs(); - set_fs(MAKE_MM_SEG(wbs)); + set_fc(wbs); if (iswrite) asm volatile (".chip 68040; ptestw (%0); .chip 68k" : : "a" (addr)); @@ -192,7 +191,7 @@ static inline unsigned long probe040(int iswrite, unsigned long addr, int wbs) asm volatile (".chip 68040; movec %%mmusr,%0; .chip 68k" : "=r" (mmusr)); - set_fs(old_fs); + set_fc(USER_DATA); return mmusr; } @@ -201,10 +200,8 @@ static inline int do_040writeback1(unsigned short wbs, unsigned long wba, unsigned long wbd) { int res = 0; - mm_segment_t old_fs = get_fs(); - /* set_fs can not be moved, otherwise put_user() may oops */ - set_fs(MAKE_MM_SEG(wbs)); + set_fc(wbs); switch (wbs & WBSIZ_040) { case BA_SIZE_BYTE: @@ -218,9 +215,7 @@ static inline int do_040writeback1(unsigned short wbs, unsigned long wba, break; } - /* set_fs can not be moved, otherwise put_user() may oops */ - set_fs(old_fs); - + set_fc(USER_DATA); pr_debug("do_040writeback1, res=%d\n", res); diff --git a/arch/m68k/mac/misc.c b/arch/m68k/mac/misc.c index 90f4e9ca1276..4fab34791758 100644 --- a/arch/m68k/mac/misc.c +++ b/arch/m68k/mac/misc.c @@ -18,7 +18,6 @@ #include #include -#include #include #include #include diff --git a/arch/m68k/mm/cache.c b/arch/m68k/mm/cache.c index e7c1cabbfac4..dde978e66f14 100644 --- a/arch/m68k/mm/cache.c +++ b/arch/m68k/mm/cache.c @@ -90,11 +90,9 @@ void flush_icache_user_range(unsigned long address, unsigned long endaddr) void flush_icache_range(unsigned long address, unsigned long endaddr) { - mm_segment_t old_fs = get_fs(); - - set_fs(KERNEL_DS); + set_fc(SUPER_DATA); flush_icache_user_range(address, endaddr); - set_fs(old_fs); + set_fc(USER_DATA); } EXPORT_SYMBOL(flush_icache_range); diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c index 5d749e188246..1b47bec15832 100644 --- a/arch/m68k/mm/init.c +++ b/arch/m68k/mm/init.c @@ -72,12 +72,6 @@ void __init paging_init(void) if (!empty_zero_page) panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, PAGE_SIZE, PAGE_SIZE); - - /* - * Set up SFC/DFC registers (user data space). - */ - set_fs (USER_DS); - max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT; free_area_init(max_zone_pfn); } diff --git a/arch/m68k/mm/kmap.c b/arch/m68k/mm/kmap.c index 1269d513b221..20ddf71b43d0 100644 --- a/arch/m68k/mm/kmap.c +++ b/arch/m68k/mm/kmap.c @@ -17,7 +17,6 @@ #include #include -#include #include #include #include diff --git a/arch/m68k/mm/memory.c b/arch/m68k/mm/memory.c index fe75aecfb238..c2c03b0a1567 100644 --- a/arch/m68k/mm/memory.c +++ b/arch/m68k/mm/memory.c @@ -15,7 +15,6 @@ #include #include -#include #include #include #include diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c index 3a653f0a4188..9f3f77785aa7 100644 --- a/arch/m68k/mm/motorola.c +++ b/arch/m68k/mm/motorola.c @@ -467,7 +467,7 @@ void __init paging_init(void) /* * Set up SFC/DFC registers */ - set_fs(KERNEL_DS); + set_fc(USER_DATA); #ifdef DEBUG printk ("before free_area_init\n"); diff --git a/arch/m68k/sun3/config.c b/arch/m68k/sun3/config.c index f7dd47232b6c..203f428a0344 100644 --- a/arch/m68k/sun3/config.c +++ b/arch/m68k/sun3/config.c @@ -31,7 +31,6 @@ #include #include #include -#include #include char sun3_reserved_pmeg[SUN3_PMEGS_NUM]; @@ -89,7 +88,7 @@ void __init sun3_init(void) sun3_reserved_pmeg[249] = 1; sun3_reserved_pmeg[252] = 1; sun3_reserved_pmeg[253] = 1; - set_fs(KERNEL_DS); + set_fc(USER_DATA); } /* Without this, Bad Things happen when something calls arch_reset. */ diff --git a/arch/m68k/sun3/mmu_emu.c b/arch/m68k/sun3/mmu_emu.c index 7aa879b7c7ff..7ec20817c0c9 100644 --- a/arch/m68k/sun3/mmu_emu.c +++ b/arch/m68k/sun3/mmu_emu.c @@ -23,7 +23,6 @@ #include #include #include -#include #include #include #include @@ -191,14 +190,13 @@ void __init mmu_emu_init(unsigned long bootmem_end) for(seg = 0; seg < PAGE_OFFSET; seg += SUN3_PMEG_SIZE) sun3_put_segmap(seg, SUN3_INVALID_PMEG); - set_fs(MAKE_MM_SEG(3)); + set_fc(3); for(seg = 0; seg < 0x10000000; seg += SUN3_PMEG_SIZE) { i = sun3_get_segmap(seg); for(j = 1; j < CONTEXTS_NUM; j++) (*(romvec->pv_setctxt))(j, (void *)seg, i); } - set_fs(KERNEL_DS); - + set_fc(USER_DATA); } /* erase the mappings for a dead context. Uses the pg_dir for hints diff --git a/arch/m68k/sun3/sun3ints.c b/arch/m68k/sun3/sun3ints.c index 41ae422119d3..36cc280a4505 100644 --- a/arch/m68k/sun3/sun3ints.c +++ b/arch/m68k/sun3/sun3ints.c @@ -11,7 +11,6 @@ #include #include #include -#include #include #include #include diff --git a/arch/m68k/sun3x/prom.c b/arch/m68k/sun3x/prom.c index 74d2fe57524b..64c23bfaa90c 100644 --- a/arch/m68k/sun3x/prom.c +++ b/arch/m68k/sun3x/prom.c @@ -14,7 +14,6 @@ #include #include #include -#include #include #include #include -- cgit v1.2.3