static int __spu_trap_data_map(struct spu *spu, unsigned long ea, u64 dsisr)
{
pr_debug("%s, %lx, %lx\n", __FUNCTION__, dsisr, ea);
/* Handle kernel space hash faults immediately.
User hash faults need to be deferred to process context. */
if ((dsisr & MFC_DSISR_PTE_NOT_FOUND)
&& REGION_ID(ea) != USER_REGION_ID
&& hash_page(ea, _PAGE_PRESENT, 0x300) == 0) {
spu_restart_dma(spu);
return 0;
}
if (test_bit(SPU_CONTEXT_SWITCH_ACTIVE, &spu->flags)) {
printk("%s: invalid access during switch!\n", __func__);
return 1;
}
spu->dar = ea;
spu->dsisr = dsisr;
mb();
if (spu->stop_callback)
spu->stop_callback(spu);
return 0;
}
int spufs_handle_class1(struct spu_context *ctx)
{
u64 ea, dsisr, access;
unsigned long flags;
unsigned flt = 0;
int ret;
ea = ctx->csa.class_1_dar;
dsisr = ctx->csa.class_1_dsisr;
if (!(dsisr & (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED)))
return 0;
spuctx_switch_state(ctx, SPU_UTIL_IOWAIT);
pr_debug("ctx %p: ea %016llx, dsisr %016llx state %d\n", ctx, ea,
dsisr, ctx->state);
ctx->stats.hash_flt++;
if (ctx->state == SPU_STATE_RUNNABLE)
ctx->spu->stats.hash_flt++;
spu_release(ctx);
access = (_PAGE_PRESENT | _PAGE_USER);
access |= (dsisr & MFC_DSISR_ACCESS_PUT) ? _PAGE_RW : 0UL;
local_irq_save(flags);
ret = hash_page(ea, access, 0x300);
local_irq_restore(flags);
if (ret)
ret = spu_handle_mm_fault(current->mm, ea, dsisr, &flt);
mutex_lock(&ctx->state_mutex);
ctx->csa.class_1_dar = ctx->csa.class_1_dsisr = 0;
if (!ret) {
if (flt & VM_FAULT_MAJOR)
ctx->stats.maj_flt++;
else
ctx->stats.min_flt++;
if (ctx->state == SPU_STATE_RUNNABLE) {
if (flt & VM_FAULT_MAJOR)
ctx->spu->stats.maj_flt++;
else
ctx->spu->stats.min_flt++;
}
if (ctx->spu)
ctx->ops->restart_dma(ctx);
} else
spufs_handle_event(ctx, ea, SPE_EVENT_SPE_DATA_STORAGE);
spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
return ret;
}
/*
* bottom half handler for page faults, we can't do this from
* interrupt context, since we might need to sleep.
* we also need to give up the mutex so we can get scheduled
* out while waiting for the backing store.
*
* TODO: try calling hash_page from the interrupt handler first
* in order to speed up the easy case.
*/
int spufs_handle_class1(struct spu_context *ctx)
{
u64 ea, dsisr, access;
unsigned long flags;
unsigned flt = 0;
int ret;
/*
* dar and dsisr get passed from the registers
* to the spu_context, to this function, but not
* back to the spu if it gets scheduled again.
*
* if we don't handle the fault for a saved context
* in time, we can still expect to get the same fault
* the immediately after the context restore.
*/
ea = ctx->csa.class_1_dar;
dsisr = ctx->csa.class_1_dsisr;
if (!(dsisr & (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED)))
return 0;
spuctx_switch_state(ctx, SPU_UTIL_IOWAIT);
pr_debug("ctx %p: ea %016llx, dsisr %016llx state %d\n", ctx, ea,
dsisr, ctx->state);
ctx->stats.hash_flt++;
if (ctx->state == SPU_STATE_RUNNABLE)
ctx->spu->stats.hash_flt++;
/* we must not hold the lock when entering spu_handle_mm_fault */
spu_release(ctx);
access = (_PAGE_PRESENT | _PAGE_USER);
access |= (dsisr & MFC_DSISR_ACCESS_PUT) ? _PAGE_RW : 0UL;
local_irq_save(flags);
ret = hash_page(ea, access, 0x300);
local_irq_restore(flags);
/* hashing failed, so try the actual fault handler */
if (ret)
ret = spu_handle_mm_fault(current->mm, ea, dsisr, &flt);
/*
* This is nasty: we need the state_mutex for all the bookkeeping even
* if the syscall was interrupted by a signal. ewww.
*/
mutex_lock(&ctx->state_mutex);
/*
* Clear dsisr under ctxt lock after handling the fault, so that
* time slicing will not preempt the context while the page fault
* handler is running. Context switch code removes mappings.
*/
ctx->csa.class_1_dar = ctx->csa.class_1_dsisr = 0;
/*
* If we handled the fault successfully and are in runnable
* state, restart the DMA.
* In case of unhandled error report the problem to user space.
*/
if (!ret) {
if (flt & VM_FAULT_MAJOR)
ctx->stats.maj_flt++;
else
ctx->stats.min_flt++;
if (ctx->state == SPU_STATE_RUNNABLE) {
if (flt & VM_FAULT_MAJOR)
ctx->spu->stats.maj_flt++;
else
ctx->spu->stats.min_flt++;
}
if (ctx->spu)
ctx->ops->restart_dma(ctx);
} else
spufs_handle_event(ctx, ea, SPE_EVENT_SPE_DATA_STORAGE);
spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
return ret;
}
