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Release 4.14 arch/powerpc/platforms/cell/spufs/fault.c

/*
 * Low-level SPU handling
 *
 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
 *
 * Author: Arnd Bergmann <arndb@de.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <linux/sched/signal.h>
#include <linux/mm.h>

#include <asm/spu.h>
#include <asm/spu_csa.h>

#include "spufs.h"

/**
 * Handle an SPE event, depending on context SPU_CREATE_EVENTS_ENABLED flag.
 *
 * If the context was created with events, we just set the return event.
 * Otherwise, send an appropriate signal to the process.
 */

static void spufs_handle_event(struct spu_context *ctx, unsigned long ea, int type) { siginfo_t info; if (ctx->flags & SPU_CREATE_EVENTS_ENABLED) { ctx->event_return |= type; wake_up_all(&ctx->stop_wq); return; } memset(&info, 0, sizeof(info)); switch (type) { case SPE_EVENT_INVALID_DMA: info.si_signo = SIGBUS; info.si_code = BUS_OBJERR; break; case SPE_EVENT_SPE_DATA_STORAGE: info.si_signo = SIGSEGV; info.si_addr = (void __user *)ea; info.si_code = SEGV_ACCERR; ctx->ops->restart_dma(ctx); break; case SPE_EVENT_DMA_ALIGNMENT: info.si_signo = SIGBUS; /* DAR isn't set for an alignment fault :( */ info.si_code = BUS_ADRALN; break; case SPE_EVENT_SPE_ERROR: info.si_signo = SIGILL; info.si_addr = (void __user *)(unsigned long) ctx->ops->npc_read(ctx) - 4; info.si_code = ILL_ILLOPC; break; } if (info.si_signo) force_sig_info(info.si_signo, &info, current); }

Contributors

PersonTokensPropCommitsCommitProp
Jeremy Kerr12163.02%250.00%
Arnd Bergmann6031.25%125.00%
Andre Detsch115.73%125.00%
Total192100.00%4100.00%


int spufs_handle_class0(struct spu_context *ctx) { unsigned long stat = ctx->csa.class_0_pending & CLASS0_INTR_MASK; if (likely(!stat)) return 0; if (stat & CLASS0_DMA_ALIGNMENT_INTR) spufs_handle_event(ctx, ctx->csa.class_0_dar, SPE_EVENT_DMA_ALIGNMENT); if (stat & CLASS0_INVALID_DMA_COMMAND_INTR) spufs_handle_event(ctx, ctx->csa.class_0_dar, SPE_EVENT_INVALID_DMA); if (stat & CLASS0_SPU_ERROR_INTR) spufs_handle_event(ctx, ctx->csa.class_0_dar, SPE_EVENT_SPE_ERROR); ctx->csa.class_0_pending = 0; return -EIO; }

Contributors

PersonTokensPropCommitsCommitProp
Jeremy Kerr7977.45%250.00%
Arnd Bergmann1211.76%125.00%
Luke Browning1110.78%125.00%
Total102100.00%4100.00%

/* * 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 copro_handle_mm_fault */ spu_release(ctx); access = (_PAGE_PRESENT | _PAGE_READ); access |= (dsisr & MFC_DSISR_ACCESS_PUT) ? _PAGE_WRITE : 0UL; local_irq_save(flags); ret = hash_page(ea, access, 0x300, dsisr); local_irq_restore(flags); /* hashing failed, so try the actual fault handler */ if (ret) ret = copro_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; }

Contributors

PersonTokensPropCommitsCommitProp
Arnd Bergmann16755.48%17.69%
Christoph Hellwig10534.88%430.77%
Jeremy Kerr165.32%215.38%
Luke Browning41.33%17.69%
Aneesh Kumar K.V41.33%215.38%
Andre Detsch20.66%17.69%
Ian Munsie20.66%17.69%
Stephen Rothwell10.33%17.69%
Total301100.00%13100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Arnd Bergmann25541.60%16.67%
Jeremy Kerr21735.40%213.33%
Christoph Hellwig10517.13%426.67%
Luke Browning152.45%16.67%
Andre Detsch132.12%213.33%
Aneesh Kumar K.V40.65%213.33%
Ian Munsie20.33%16.67%
Ingo Molnar10.16%16.67%
Stephen Rothwell10.16%16.67%
Total613100.00%15100.00%
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