diff options
Diffstat (limited to 'arch/mips/mm/tlbex.c')
| -rw-r--r-- | arch/mips/mm/tlbex.c | 73 |
1 files changed, 49 insertions, 24 deletions
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index 678e6339846..d9a18b2b7f8 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -6,7 +6,7 @@ * Synthesize TLB refill handlers at runtime. * * Copyright (C) 2004, 2005, 2006, 2008 Thiemo Seufer - * Copyright (C) 2005, 2007 Maciej W. Rozycki + * Copyright (C) 2005, 2007, 2008, 2009 Maciej W. Rozycki * Copyright (C) 2006 Ralf Baechle (ralf@linux-mips.org) * * ... and the days got worse and worse and now you see @@ -19,6 +19,7 @@ * (Condolences to Napoleon XIV) */ +#include <linux/bug.h> #include <linux/kernel.h> #include <linux/types.h> #include <linux/string.h> @@ -732,36 +733,60 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) uasm_copy_handler(relocs, labels, tlb_handler, p, f); final_len = p - tlb_handler; } else { - /* - * Split two instructions before the end. One for the - * branch and one for the instruction in the delay - * slot. - */ - u32 *split = tlb_handler + MIPS64_REFILL_INSNS - 2; +#ifdef MODULE_START + const enum label_id ls = label_module_alloc; +#else + const enum label_id ls = label_vmalloc; +#endif + u32 *split; + int ov = 0; + int i; + + for (i = 0; i < ARRAY_SIZE(labels) && labels[i].lab != ls; i++) + ; + BUG_ON(i == ARRAY_SIZE(labels)); + split = labels[i].addr; /* - * Find the split point. If the branch would fall in - * a delay slot, we must back up an additional - * instruction so that it is no longer in a delay - * slot. + * See if we have overflown one way or the other. */ - if (uasm_insn_has_bdelay(relocs, split - 1)) - split--; - + if (split > tlb_handler + MIPS64_REFILL_INSNS || + split < p - MIPS64_REFILL_INSNS) + ov = 1; + + if (ov) { + /* + * Split two instructions before the end. One + * for the branch and one for the instruction + * in the delay slot. + */ + split = tlb_handler + MIPS64_REFILL_INSNS - 2; + + /* + * If the branch would fall in a delay slot, + * we must back up an additional instruction + * so that it is no longer in a delay slot. + */ + if (uasm_insn_has_bdelay(relocs, split - 1)) + split--; + } /* Copy first part of the handler. */ uasm_copy_handler(relocs, labels, tlb_handler, split, f); f += split - tlb_handler; - /* Insert branch. */ - uasm_l_split(&l, final_handler); - uasm_il_b(&f, &r, label_split); - if (uasm_insn_has_bdelay(relocs, split)) - uasm_i_nop(&f); - else { - uasm_copy_handler(relocs, labels, split, split + 1, f); - uasm_move_labels(labels, f, f + 1, -1); - f++; - split++; + if (ov) { + /* Insert branch. */ + uasm_l_split(&l, final_handler); + uasm_il_b(&f, &r, label_split); + if (uasm_insn_has_bdelay(relocs, split)) + uasm_i_nop(&f); + else { + uasm_copy_handler(relocs, labels, + split, split + 1, f); + uasm_move_labels(labels, f, f + 1, -1); + f++; + split++; + } } /* Copy the rest of the handler. */ |