diff options
Diffstat (limited to 'arch/sparc/kernel/unaligned.c')
-rw-r--r-- | arch/sparc/kernel/unaligned.c | 390 |
1 files changed, 0 insertions, 390 deletions
diff --git a/arch/sparc/kernel/unaligned.c b/arch/sparc/kernel/unaligned.c deleted file mode 100644 index c2a28c5ad650..000000000000 --- a/arch/sparc/kernel/unaligned.c +++ /dev/null @@ -1,390 +0,0 @@ -/* - * unaligned.c: Unaligned load/store trap handling with special - * cases for the kernel to do them more quickly. - * - * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) - * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz) - */ - - -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/module.h> -#include <asm/ptrace.h> -#include <asm/processor.h> -#include <asm/system.h> -#include <asm/uaccess.h> -#include <linux/smp.h> -#include <linux/smp_lock.h> - -/* #define DEBUG_MNA */ - -enum direction { - load, /* ld, ldd, ldh, ldsh */ - store, /* st, std, sth, stsh */ - both, /* Swap, ldstub, etc. */ - fpload, - fpstore, - invalid, -}; - -#ifdef DEBUG_MNA -static char *dirstrings[] = { - "load", "store", "both", "fpload", "fpstore", "invalid" -}; -#endif - -static inline enum direction decode_direction(unsigned int insn) -{ - unsigned long tmp = (insn >> 21) & 1; - - if(!tmp) - return load; - else { - if(((insn>>19)&0x3f) == 15) - return both; - else - return store; - } -} - -/* 8 = double-word, 4 = word, 2 = half-word */ -static inline int decode_access_size(unsigned int insn) -{ - insn = (insn >> 19) & 3; - - if(!insn) - return 4; - else if(insn == 3) - return 8; - else if(insn == 2) - return 2; - else { - printk("Impossible unaligned trap. insn=%08x\n", insn); - die_if_kernel("Byte sized unaligned access?!?!", current->thread.kregs); - return 4; /* just to keep gcc happy. */ - } -} - -/* 0x400000 = signed, 0 = unsigned */ -static inline int decode_signedness(unsigned int insn) -{ - return (insn & 0x400000); -} - -static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2, - unsigned int rd) -{ - if(rs2 >= 16 || rs1 >= 16 || rd >= 16) { - /* Wheee... */ - __asm__ __volatile__("save %sp, -0x40, %sp\n\t" - "save %sp, -0x40, %sp\n\t" - "save %sp, -0x40, %sp\n\t" - "save %sp, -0x40, %sp\n\t" - "save %sp, -0x40, %sp\n\t" - "save %sp, -0x40, %sp\n\t" - "save %sp, -0x40, %sp\n\t" - "restore; restore; restore; restore;\n\t" - "restore; restore; restore;\n\t"); - } -} - -static inline int sign_extend_imm13(int imm) -{ - return imm << 19 >> 19; -} - -static inline unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs) -{ - struct reg_window *win; - - if(reg < 16) - return (!reg ? 0 : regs->u_regs[reg]); - - /* Ho hum, the slightly complicated case. */ - win = (struct reg_window *) regs->u_regs[UREG_FP]; - return win->locals[reg - 16]; /* yes, I know what this does... */ -} - -static inline unsigned long safe_fetch_reg(unsigned int reg, struct pt_regs *regs) -{ - struct reg_window __user *win; - unsigned long ret; - - if (reg < 16) - return (!reg ? 0 : regs->u_regs[reg]); - - /* Ho hum, the slightly complicated case. */ - win = (struct reg_window __user *) regs->u_regs[UREG_FP]; - - if ((unsigned long)win & 3) - return -1; - - if (get_user(ret, &win->locals[reg - 16])) - return -1; - - return ret; -} - -static inline unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs) -{ - struct reg_window *win; - - if(reg < 16) - return ®s->u_regs[reg]; - win = (struct reg_window *) regs->u_regs[UREG_FP]; - return &win->locals[reg - 16]; -} - -static unsigned long compute_effective_address(struct pt_regs *regs, - unsigned int insn) -{ - unsigned int rs1 = (insn >> 14) & 0x1f; - unsigned int rs2 = insn & 0x1f; - unsigned int rd = (insn >> 25) & 0x1f; - - if(insn & 0x2000) { - maybe_flush_windows(rs1, 0, rd); - return (fetch_reg(rs1, regs) + sign_extend_imm13(insn)); - } else { - maybe_flush_windows(rs1, rs2, rd); - return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs)); - } -} - -unsigned long safe_compute_effective_address(struct pt_regs *regs, - unsigned int insn) -{ - unsigned int rs1 = (insn >> 14) & 0x1f; - unsigned int rs2 = insn & 0x1f; - unsigned int rd = (insn >> 25) & 0x1f; - - if(insn & 0x2000) { - maybe_flush_windows(rs1, 0, rd); - return (safe_fetch_reg(rs1, regs) + sign_extend_imm13(insn)); - } else { - maybe_flush_windows(rs1, rs2, rd); - return (safe_fetch_reg(rs1, regs) + safe_fetch_reg(rs2, regs)); - } -} - -/* This is just to make gcc think panic does return... */ -static void unaligned_panic(char *str) -{ - panic(str); -} - -/* una_asm.S */ -extern int do_int_load(unsigned long *dest_reg, int size, - unsigned long *saddr, int is_signed); -extern int __do_int_store(unsigned long *dst_addr, int size, - unsigned long *src_val); - -static int do_int_store(int reg_num, int size, unsigned long *dst_addr, - struct pt_regs *regs) -{ - unsigned long zero[2] = { 0, 0 }; - unsigned long *src_val; - - if (reg_num) - src_val = fetch_reg_addr(reg_num, regs); - else { - src_val = &zero[0]; - if (size == 8) - zero[1] = fetch_reg(1, regs); - } - return __do_int_store(dst_addr, size, src_val); -} - -extern void smp_capture(void); -extern void smp_release(void); - -static inline void advance(struct pt_regs *regs) -{ - regs->pc = regs->npc; - regs->npc += 4; -} - -static inline int floating_point_load_or_store_p(unsigned int insn) -{ - return (insn >> 24) & 1; -} - -static inline int ok_for_kernel(unsigned int insn) -{ - return !floating_point_load_or_store_p(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); - - if (!fixup) { - 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"); - } else - printk(KERN_ALERT "Unable to handle kernel paging request in mna handler"); - printk(KERN_ALERT " at virtual address %08lx\n",address); - printk(KERN_ALERT "current->{mm,active_mm}->context = %08lx\n", - (current->mm ? current->mm->context : - current->active_mm->context)); - printk(KERN_ALERT "current->{mm,active_mm}->pgd = %08lx\n", - (current->mm ? (unsigned long) current->mm->pgd : - (unsigned long) current->active_mm->pgd)); - die_if_kernel("Oops", regs); - /* Not reached */ - } - regs->pc = fixup; - regs->npc = regs->pc + 4; - regs->u_regs [UREG_G2] = g2; -} - -asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn) -{ - enum direction dir = decode_direction(insn); - int size = decode_access_size(insn); - - if(!ok_for_kernel(insn) || dir == both) { - printk("Unsupported unaligned load/store trap for kernel at <%08lx>.\n", - regs->pc); - unaligned_panic("Wheee. Kernel does fpu/atomic unaligned load/store."); - } else { - unsigned long addr = compute_effective_address(regs, insn); - int err; - -#ifdef DEBUG_MNA - printk("KMNA: pc=%08lx [dir=%s addr=%08lx size=%d] retpc[%08lx]\n", - regs->pc, dirstrings[dir], addr, size, regs->u_regs[UREG_RETPC]); -#endif - switch (dir) { - case load: - err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f), - regs), - size, (unsigned long *) addr, - decode_signedness(insn)); - break; - - case store: - err = do_int_store(((insn>>25)&0x1f), size, - (unsigned long *) addr, regs); - break; - default: - panic("Impossible kernel unaligned trap."); - /* Not reached... */ - } - if (err) - kernel_mna_trap_fault(regs, insn); - else - advance(regs); - } -} - -static inline int ok_for_user(struct pt_regs *regs, unsigned int insn, - enum direction dir) -{ - unsigned int reg; - int check = (dir == load) ? VERIFY_READ : VERIFY_WRITE; - int size = ((insn >> 19) & 3) == 3 ? 8 : 4; - - if ((regs->pc | regs->npc) & 3) - return 0; - - /* Must access_ok() in all the necessary places. */ -#define WINREG_ADDR(regnum) \ - ((void __user *)(((unsigned long *)regs->u_regs[UREG_FP])+(regnum))) - - reg = (insn >> 25) & 0x1f; - if (reg >= 16) { - if (!access_ok(check, WINREG_ADDR(reg - 16), size)) - return -EFAULT; - } - reg = (insn >> 14) & 0x1f; - if (reg >= 16) { - if (!access_ok(check, WINREG_ADDR(reg - 16), size)) - return -EFAULT; - } - if (!(insn & 0x2000)) { - reg = (insn & 0x1f); - if (reg >= 16) { - if (!access_ok(check, WINREG_ADDR(reg - 16), size)) - return -EFAULT; - } - } -#undef WINREG_ADDR - return 0; -} - -static void user_mna_trap_fault(struct pt_regs *regs, unsigned int insn) -{ - siginfo_t info; - - info.si_signo = SIGBUS; - info.si_errno = 0; - info.si_code = BUS_ADRALN; - info.si_addr = (void __user *)safe_compute_effective_address(regs, insn); - info.si_trapno = 0; - send_sig_info(SIGBUS, &info, current); -} - -asmlinkage void user_unaligned_trap(struct pt_regs *regs, unsigned int insn) -{ - enum direction dir; - - lock_kernel(); - if(!(current->thread.flags & SPARC_FLAG_UNALIGNED) || - (((insn >> 30) & 3) != 3)) - goto kill_user; - dir = decode_direction(insn); - if(!ok_for_user(regs, insn, dir)) { - goto kill_user; - } else { - int err, size = decode_access_size(insn); - unsigned long addr; - - if(floating_point_load_or_store_p(insn)) { - printk("User FPU load/store unaligned unsupported.\n"); - goto kill_user; - } - - addr = compute_effective_address(regs, insn); - switch(dir) { - case load: - err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f), - regs), - size, (unsigned long *) addr, - decode_signedness(insn)); - break; - - case store: - err = do_int_store(((insn>>25)&0x1f), size, - (unsigned long *) addr, regs); - break; - - case both: - /* - * This was supported in 2.4. However, we question - * the value of SWAP instruction across word boundaries. - */ - printk("Unaligned SWAP unsupported.\n"); - err = -EFAULT; - break; - - default: - unaligned_panic("Impossible user unaligned trap."); - goto out; - } - if (err) - goto kill_user; - else - advance(regs); - goto out; - } - -kill_user: - user_mna_trap_fault(regs, insn); -out: - unlock_kernel(); -} |