summaryrefslogtreecommitdiffstats
path: root/arch/mips/kernel/unaligned.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/kernel/unaligned.c')
-rw-r--r--arch/mips/kernel/unaligned.c74
1 files changed, 73 insertions, 1 deletions
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index eb3efd1..990354d 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -891,6 +891,9 @@ static void emulate_load_store_insn(struct pt_regs *regs,
#ifdef CONFIG_EVA
mm_segment_t seg;
#endif
+ union fpureg *fpr;
+ enum msa_2b_fmt df;
+ unsigned int wd;
origpc = (unsigned long)pc;
orig31 = regs->regs[31];
@@ -1202,6 +1205,75 @@ static void emulate_load_store_insn(struct pt_regs *regs,
break;
return;
+ case msa_op:
+ if (!cpu_has_msa)
+ goto sigill;
+
+ /*
+ * If we've reached this point then userland should have taken
+ * the MSA disabled exception & initialised vector context at
+ * some point in the past.
+ */
+ BUG_ON(!thread_msa_context_live());
+
+ df = insn.msa_mi10_format.df;
+ wd = insn.msa_mi10_format.wd;
+ fpr = &current->thread.fpu.fpr[wd];
+
+ switch (insn.msa_mi10_format.func) {
+ case msa_ld_op:
+ if (!access_ok(VERIFY_READ, addr, sizeof(*fpr)))
+ goto sigbus;
+
+ /*
+ * Disable preemption to avoid a race between copying
+ * state from userland, migrating to another CPU and
+ * updating the hardware vector register below.
+ */
+ preempt_disable();
+
+ res = __copy_from_user_inatomic(fpr, addr,
+ sizeof(*fpr));
+ if (res)
+ goto fault;
+
+ /*
+ * Update the hardware register if it is in use by the
+ * task in this quantum, in order to avoid having to
+ * save & restore the whole vector context.
+ */
+ if (test_thread_flag(TIF_USEDMSA))
+ write_msa_wr(wd, fpr, df);
+
+ preempt_enable();
+ break;
+
+ case msa_st_op:
+ if (!access_ok(VERIFY_WRITE, addr, sizeof(*fpr)))
+ goto sigbus;
+
+ /*
+ * Update from the hardware register if it is in use by
+ * the task in this quantum, in order to avoid having to
+ * save & restore the whole vector context.
+ */
+ preempt_disable();
+ if (test_thread_flag(TIF_USEDMSA))
+ read_msa_wr(wd, fpr, df);
+ preempt_enable();
+
+ res = __copy_to_user_inatomic(addr, fpr, sizeof(*fpr));
+ if (res)
+ goto fault;
+ break;
+
+ default:
+ goto sigbus;
+ }
+
+ compute_return_epc(regs);
+ break;
+
#ifndef CONFIG_CPU_MIPSR6
/*
* COP2 is available to implementor for application specific use.
@@ -2240,5 +2312,5 @@ static int __init debugfs_unaligned(void)
return -ENOMEM;
return 0;
}
-__initcall(debugfs_unaligned);
+arch_initcall(debugfs_unaligned);
#endif
OpenPOWER on IntegriCloud