From 595c73071e6641e59b83911fbb4026e767471000 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 23 Sep 2016 17:53:52 -0700 Subject: libnvdimm, region: fix flush hint table thinko The definition of the flush hint table as: void __iomem *flush_wpq[0][0]; ...passed the unit test, but is broken as flush_wpq[0][1] and flush_wpq[1][0] refer to the same entry. Fix this to use a helper that calculates a slot in the table based on the geometry of flush hints in the region. This is important to get right since virtualization solutions use this mechanism to trigger hypervisor flushes to platform persistence. Reported-by: Dave Jiang Tested-by: Dave Jiang Signed-off-by: Dan Williams --- drivers/nvdimm/nd.h | 22 ++++++++++++++++++++-- drivers/nvdimm/region_devs.c | 20 ++++++++++++-------- 2 files changed, 32 insertions(+), 10 deletions(-) (limited to 'drivers') diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index 8024a0ef86d3..0b78a8211f4a 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -52,10 +52,28 @@ struct nvdimm_drvdata { struct nd_region_data { int ns_count; int ns_active; - unsigned int flush_mask; - void __iomem *flush_wpq[0][0]; + unsigned int hints_shift; + void __iomem *flush_wpq[0]; }; +static inline void __iomem *ndrd_get_flush_wpq(struct nd_region_data *ndrd, + int dimm, int hint) +{ + unsigned int num = 1 << ndrd->hints_shift; + unsigned int mask = num - 1; + + return ndrd->flush_wpq[dimm * num + (hint & mask)]; +} + +static inline void ndrd_set_flush_wpq(struct nd_region_data *ndrd, int dimm, + int hint, void __iomem *flush) +{ + unsigned int num = 1 << ndrd->hints_shift; + unsigned int mask = num - 1; + + ndrd->flush_wpq[dimm * num + (hint & mask)] = flush; +} + static inline struct nd_namespace_index *to_namespace_index( struct nvdimm_drvdata *ndd, int i) { diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index 4eef88eb5144..4c0ac4abb629 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -38,7 +38,7 @@ static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm, dev_dbg(dev, "%s: map %d flush address%s\n", nvdimm_name(nvdimm), nvdimm->num_flush, nvdimm->num_flush == 1 ? "" : "es"); - for (i = 0; i < nvdimm->num_flush; i++) { + for (i = 0; i < (1 << ndrd->hints_shift); i++) { struct resource *res = &nvdimm->flush_wpq[i]; unsigned long pfn = PHYS_PFN(res->start); void __iomem *flush_page; @@ -54,14 +54,15 @@ static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm, if (j < i) flush_page = (void __iomem *) ((unsigned long) - ndrd->flush_wpq[dimm][j] & PAGE_MASK); + ndrd_get_flush_wpq(ndrd, dimm, j) + & PAGE_MASK); else flush_page = devm_nvdimm_ioremap(dev, PFN_PHYS(pfn), PAGE_SIZE); if (!flush_page) return -ENXIO; - ndrd->flush_wpq[dimm][i] = flush_page - + (res->start & ~PAGE_MASK); + ndrd_set_flush_wpq(ndrd, dimm, i, flush_page + + (res->start & ~PAGE_MASK)); } return 0; @@ -93,7 +94,10 @@ int nd_region_activate(struct nd_region *nd_region) return -ENOMEM; dev_set_drvdata(dev, ndrd); - ndrd->flush_mask = (1 << ilog2(num_flush)) - 1; + if (!num_flush) + return 0; + + ndrd->hints_shift = ilog2(num_flush); for (i = 0; i < nd_region->ndr_mappings; i++) { struct nd_mapping *nd_mapping = &nd_region->mapping[i]; struct nvdimm *nvdimm = nd_mapping->nvdimm; @@ -900,8 +904,8 @@ void nvdimm_flush(struct nd_region *nd_region) */ wmb(); for (i = 0; i < nd_region->ndr_mappings; i++) - if (ndrd->flush_wpq[i][0]) - writeq(1, ndrd->flush_wpq[i][idx & ndrd->flush_mask]); + if (ndrd_get_flush_wpq(ndrd, i, 0)) + writeq(1, ndrd_get_flush_wpq(ndrd, i, idx)); wmb(); } EXPORT_SYMBOL_GPL(nvdimm_flush); @@ -925,7 +929,7 @@ int nvdimm_has_flush(struct nd_region *nd_region) for (i = 0; i < nd_region->ndr_mappings; i++) /* flush hints present, flushing required */ - if (ndrd->flush_wpq[i][0]) + if (ndrd_get_flush_wpq(ndrd, i, 0)) return 1; /* -- cgit v1.2.3