diff options
Diffstat (limited to 'drivers/cxl/core/region.c')
-rw-r--r-- | drivers/cxl/core/region.c | 102 |
1 files changed, 63 insertions, 39 deletions
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index 013f3656e661..38db377e13f1 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -125,10 +125,38 @@ static struct cxl_region_ref *cxl_rr_load(struct cxl_port *port, return xa_load(&port->regions, (unsigned long)cxlr); } +static int cxl_region_invalidate_memregion(struct cxl_region *cxlr) +{ + if (!cpu_cache_has_invalidate_memregion()) { + if (IS_ENABLED(CONFIG_CXL_REGION_INVALIDATION_TEST)) { + dev_warn_once( + &cxlr->dev, + "Bypassing cpu_cache_invalidate_memregion() for testing!\n"); + return 0; + } else { + dev_err(&cxlr->dev, + "Failed to synchronize CPU cache state\n"); + return -ENXIO; + } + } + + cpu_cache_invalidate_memregion(IORES_DESC_CXL); + return 0; +} + static int cxl_region_decode_reset(struct cxl_region *cxlr, int count) { struct cxl_region_params *p = &cxlr->params; - int i; + int i, rc = 0; + + /* + * Before region teardown attempt to flush, and if the flush + * fails cancel the region teardown for data consistency + * concerns + */ + rc = cxl_region_invalidate_memregion(cxlr); + if (rc) + return rc; for (i = count - 1; i >= 0; i--) { struct cxl_endpoint_decoder *cxled = p->targets[i]; @@ -136,7 +164,6 @@ static int cxl_region_decode_reset(struct cxl_region *cxlr, int count) struct cxl_port *iter = cxled_to_port(cxled); struct cxl_dev_state *cxlds = cxlmd->cxlds; struct cxl_ep *ep; - int rc = 0; if (cxlds->rcd) goto endpoint_reset; @@ -155,14 +182,19 @@ static int cxl_region_decode_reset(struct cxl_region *cxlr, int count) rc = cxld->reset(cxld); if (rc) return rc; + set_bit(CXL_REGION_F_NEEDS_RESET, &cxlr->flags); } endpoint_reset: rc = cxled->cxld.reset(&cxled->cxld); if (rc) return rc; + set_bit(CXL_REGION_F_NEEDS_RESET, &cxlr->flags); } + /* all decoders associated with this region have been torn down */ + clear_bit(CXL_REGION_F_NEEDS_RESET, &cxlr->flags); + return 0; } @@ -256,9 +288,19 @@ static ssize_t commit_store(struct device *dev, struct device_attribute *attr, goto out; } - if (commit) + /* + * Invalidate caches before region setup to drop any speculative + * consumption of this address space + */ + rc = cxl_region_invalidate_memregion(cxlr); + if (rc) + return rc; + + if (commit) { rc = cxl_region_decode_commit(cxlr); - else { + if (rc == 0) + p->state = CXL_CONFIG_COMMIT; + } else { p->state = CXL_CONFIG_RESET_PENDING; up_write(&cxl_region_rwsem); device_release_driver(&cxlr->dev); @@ -268,18 +310,20 @@ static ssize_t commit_store(struct device *dev, struct device_attribute *attr, * The lock was dropped, so need to revalidate that the reset is * still pending. */ - if (p->state == CXL_CONFIG_RESET_PENDING) + if (p->state == CXL_CONFIG_RESET_PENDING) { rc = cxl_region_decode_reset(cxlr, p->interleave_ways); + /* + * Revert to committed since there may still be active + * decoders associated with this region, or move forward + * to active to mark the reset successful + */ + if (rc) + p->state = CXL_CONFIG_COMMIT; + else + p->state = CXL_CONFIG_ACTIVE; + } } - if (rc) - goto out; - - if (commit) - p->state = CXL_CONFIG_COMMIT; - else if (p->state == CXL_CONFIG_RESET_PENDING) - p->state = CXL_CONFIG_ACTIVE; - out: up_write(&cxl_region_rwsem); @@ -1686,7 +1730,6 @@ static int cxl_region_attach(struct cxl_region *cxlr, if (rc) goto err_decrement; p->state = CXL_CONFIG_ACTIVE; - set_bit(CXL_REGION_F_INCOHERENT, &cxlr->flags); } cxled->cxld.interleave_ways = p->interleave_ways; @@ -2815,30 +2858,6 @@ out: } EXPORT_SYMBOL_NS_GPL(cxl_add_to_region, CXL); -static int cxl_region_invalidate_memregion(struct cxl_region *cxlr) -{ - if (!test_bit(CXL_REGION_F_INCOHERENT, &cxlr->flags)) - return 0; - - if (!cpu_cache_has_invalidate_memregion()) { - if (IS_ENABLED(CONFIG_CXL_REGION_INVALIDATION_TEST)) { - dev_warn_once( - &cxlr->dev, - "Bypassing cpu_cache_invalidate_memregion() for testing!\n"); - clear_bit(CXL_REGION_F_INCOHERENT, &cxlr->flags); - return 0; - } else { - dev_err(&cxlr->dev, - "Failed to synchronize CPU cache state\n"); - return -ENXIO; - } - } - - cpu_cache_invalidate_memregion(IORES_DESC_CXL); - clear_bit(CXL_REGION_F_INCOHERENT, &cxlr->flags); - return 0; -} - static int is_system_ram(struct resource *res, void *arg) { struct cxl_region *cxlr = arg; @@ -2866,7 +2885,12 @@ static int cxl_region_probe(struct device *dev) goto out; } - rc = cxl_region_invalidate_memregion(cxlr); + if (test_bit(CXL_REGION_F_NEEDS_RESET, &cxlr->flags)) { + dev_err(&cxlr->dev, + "failed to activate, re-commit region and retry\n"); + rc = -ENXIO; + goto out; + } /* * From this point on any path that changes the region's state away from |