#include <asm/vdso.h>
#include <asm/dsp.h>
#include <asm/inst.h>
+#include <asm/msa.h>
#include "signal-common.h"
return _restore_fp_context(fpregs, csr);
}
+/*
+ * Extended context handling.
+ */
+
+static inline void __user *sc_to_extcontext(void __user *sc)
+{
+ struct ucontext __user *uc;
+
+ /*
+ * We can just pretend the sigcontext is always embedded in a struct
+ * ucontext here, because the offset from sigcontext to extended
+ * context is the same in the struct sigframe case.
+ */
+ uc = container_of(sc, struct ucontext, uc_mcontext);
+ return &uc->uc_extcontext;
+}
+
+static int save_msa_extcontext(void __user *buf)
+{
+ struct msa_extcontext __user *msa = buf;
+ uint64_t val;
+ int i, err;
+
+ if (!thread_msa_context_live())
+ return 0;
+
+ /*
+ * Ensure that we can't lose the live MSA context between checking
+ * for it & writing it to memory.
+ */
+ preempt_disable();
+
+ if (is_msa_enabled()) {
+ /*
+ * There are no EVA versions of the vector register load/store
+ * instructions, so MSA context has to be saved to kernel memory
+ * and then copied to user memory. The save to kernel memory
+ * should already have been done when handling scalar FP
+ * context.
+ */
+ BUG_ON(config_enabled(CONFIG_EVA));
+
+ err = __put_user(read_msa_csr(), &msa->csr);
+ err |= _save_msa_all_upper(&msa->wr);
+
+ preempt_enable();
+ } else {
+ preempt_enable();
+
+ err = __put_user(current->thread.fpu.msacsr, &msa->csr);
+
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ val = get_fpr64(¤t->thread.fpu.fpr[i], 1);
+ err |= __put_user(val, &msa->wr[i]);
+ }
+ }
+
+ err |= __put_user(MSA_EXTCONTEXT_MAGIC, &msa->ext.magic);
+ err |= __put_user(sizeof(*msa), &msa->ext.size);
+
+ return err ? -EFAULT : sizeof(*msa);
+}
+
+static int restore_msa_extcontext(void __user *buf, unsigned int size)
+{
+ struct msa_extcontext __user *msa = buf;
+ unsigned long long val;
+ unsigned int csr;
+ int i, err;
+
+ if (size != sizeof(*msa))
+ return -EINVAL;
+
+ err = get_user(csr, &msa->csr);
+ if (err)
+ return err;
+
+ preempt_disable();
+
+ if (is_msa_enabled()) {
+ /*
+ * There are no EVA versions of the vector register load/store
+ * instructions, so MSA context has to be copied to kernel
+ * memory and later loaded to registers. The same is true of
+ * scalar FP context, so FPU & MSA should have already been
+ * disabled whilst handling scalar FP context.
+ */
+ BUG_ON(config_enabled(CONFIG_EVA));
+
+ write_msa_csr(csr);
+ err |= _restore_msa_all_upper(&msa->wr);
+ preempt_enable();
+ } else {
+ preempt_enable();
+
+ current->thread.fpu.msacsr = csr;
+
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ err |= __get_user(val, &msa->wr[i]);
+ set_fpr64(¤t->thread.fpu.fpr[i], 1, val);
+ }
+ }
+
+ return err;
+}
+
+static int save_extcontext(void __user *buf)
+{
+ int sz;
+
+ sz = save_msa_extcontext(buf);
+ if (sz < 0)
+ return sz;
+ buf += sz;
+
+ /* If no context was saved then trivially return */
+ if (!sz)
+ return 0;
+
+ /* Write the end marker */
+ if (__put_user(END_EXTCONTEXT_MAGIC, (u32 *)buf))
+ return -EFAULT;
+
+ sz += sizeof(((struct extcontext *)NULL)->magic);
+ return sz;
+}
+
+static int restore_extcontext(void __user *buf)
+{
+ struct extcontext ext;
+ int err;
+
+ while (1) {
+ err = __get_user(ext.magic, (unsigned int *)buf);
+ if (err)
+ return err;
+
+ if (ext.magic == END_EXTCONTEXT_MAGIC)
+ return 0;
+
+ err = __get_user(ext.size, (unsigned int *)(buf
+ + offsetof(struct extcontext, size)));
+ if (err)
+ return err;
+
+ switch (ext.magic) {
+ case MSA_EXTCONTEXT_MAGIC:
+ err = restore_msa_extcontext(buf, ext.size);
+ break;
+
+ default:
+ err = -EINVAL;
+ break;
+ }
+
+ if (err)
+ return err;
+
+ buf += ext.size;
+ }
+}
+
/*
* Helper routines
*/
uint64_t __user *fpregs = sc + abi->off_sc_fpregs;
uint32_t __user *csr = sc + abi->off_sc_fpc_csr;
uint32_t __user *used_math = sc + abi->off_sc_used_math;
- unsigned int used;
+ unsigned int used, ext_sz;
int err;
used = used_math() ? USED_FP : 0;
- if (used) {
- if (!test_thread_flag(TIF_32BIT_FPREGS))
- used |= USED_FR1;
- if (test_thread_flag(TIF_HYBRID_FPREGS))
- used |= USED_HYBRID_FPRS;
- }
+ if (!used)
+ goto fp_done;
- err = __put_user(used, used_math);
- if (err || !(used & USED_FP))
- return err;
+ if (!test_thread_flag(TIF_32BIT_FPREGS))
+ used |= USED_FR1;
+ if (test_thread_flag(TIF_HYBRID_FPREGS))
+ used |= USED_HYBRID_FPRS;
/*
* EVA does not have userland equivalents of ldc1 or sdc1, so
__put_user(0, &fpregs[31]) |
__put_user(0, csr);
if (err)
- break; /* really bad sigcontext */
+ return err; /* really bad sigcontext */
}
- return err;
+fp_done:
+ ext_sz = err = save_extcontext(sc_to_extcontext(sc));
+ if (err < 0)
+ return err;
+ used |= ext_sz ? USED_EXTCONTEXT : 0;
+
+ return __put_user(used, used_math);
}
int protected_restore_fp_context(void __user *sc)
uint32_t __user *csr = sc + abi->off_sc_fpc_csr;
uint32_t __user *used_math = sc + abi->off_sc_used_math;
unsigned int used;
- int err, sig, tmp __maybe_unused;
+ int err, sig = 0, tmp __maybe_unused;
err = __get_user(used, used_math);
conditional_used_math(used & USED_FP);
* The signal handler may have used FPU; give it up if the program
* doesn't want it following sigreturn.
*/
- if (err || !(used & USED_FP)) {
+ if (err || !(used & USED_FP))
lose_fpu(0);
+ if (err)
return err;
- }
+ if (!(used & USED_FP))
+ goto fp_done;
err = sig = fpcsr_pending(csr);
if (err < 0)
break; /* really bad sigcontext */
}
+fp_done:
+ if (used & USED_EXTCONTEXT)
+ err |= restore_extcontext(sc_to_extcontext(sc));
+
return err ?: sig;
}
return err;
}
+static size_t extcontext_max_size(void)
+{
+ size_t sz = 0;
+
+ /*
+ * The assumption here is that between this point & the point at which
+ * the extended context is saved the size of the context should only
+ * ever be able to shrink (if the task is preempted), but never grow.
+ * That is, what this function returns is an upper bound on the size of
+ * the extended context for the current task at the current time.
+ */
+
+ if (thread_msa_context_live())
+ sz += sizeof(struct msa_extcontext);
+
+ /* If any context is saved then we'll append the end marker */
+ if (sz)
+ sz += sizeof(((struct extcontext *)NULL)->magic);
+
+ return sz;
+}
+
int fpcsr_pending(unsigned int __user *fpcsr)
{
int err, sig = 0;
{
unsigned long sp;
+ /* Leave space for potential extended context */
+ frame_size += extcontext_max_size();
+
/* Default to using normal stack */
sp = regs->regs[29];
projects / linux-drm-fsl-dcu.git / blobdiff