Merge tag 'v4.20-rc6' into for-4.21/block

Pull in v4.20-rc6 to resolve the conflict in NVMe, but also to get the
two corruption fixes. We're going to be overhauling the direct dispatch
path, and we need to do that on top of the changes we made for that
in mainline.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

3 files changed, 80 insertions, 27 deletions

diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index 182258f64417..d0c621b32f72 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -111,6 +111,8 @@ resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
 		struct nd_mapping *nd_mapping, resource_size_t *overlap);
 resource_size_t nd_blk_available_dpa(struct nd_region *nd_region);
 resource_size_t nd_region_available_dpa(struct nd_region *nd_region);
+int nd_region_conflict(struct nd_region *nd_region, resource_size_t start,
+		resource_size_t size);
 resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
 		struct nd_label_id *label_id);
 int alias_dpa_busy(struct device *dev, void *data);
diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
index 24c64090169e..6f22272e8d80 100644
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -649,14 +649,47 @@ static u64 phys_pmem_align_down(struct nd_pfn *nd_pfn, u64 phys)
 			ALIGN_DOWN(phys, nd_pfn->align));
 }
 
+/*
+ * Check if pmem collides with 'System RAM', or other regions when
+ * section aligned.  Trim it accordingly.
+ */
+static void trim_pfn_device(struct nd_pfn *nd_pfn, u32 *start_pad, u32 *end_trunc)
+{
+	struct nd_namespace_common *ndns = nd_pfn->ndns;
+	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
+	struct nd_region *nd_region = to_nd_region(nd_pfn->dev.parent);
+	const resource_size_t start = nsio->res.start;
+	const resource_size_t end = start + resource_size(&nsio->res);
+	resource_size_t adjust, size;
+
+	*start_pad = 0;
+	*end_trunc = 0;
+
+	adjust = start - PHYS_SECTION_ALIGN_DOWN(start);
+	size = resource_size(&nsio->res) + adjust;
+	if (region_intersects(start - adjust, size, IORESOURCE_SYSTEM_RAM,
+				IORES_DESC_NONE) == REGION_MIXED
+			|| nd_region_conflict(nd_region, start - adjust, size))
+		*start_pad = PHYS_SECTION_ALIGN_UP(start) - start;
+
+	/* Now check that end of the range does not collide. */
+	adjust = PHYS_SECTION_ALIGN_UP(end) - end;
+	size = resource_size(&nsio->res) + adjust;
+	if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
+				IORES_DESC_NONE) == REGION_MIXED
+			|| !IS_ALIGNED(end, nd_pfn->align)
+			|| nd_region_conflict(nd_region, start, size + adjust))
+		*end_trunc = end - phys_pmem_align_down(nd_pfn, end);
+}
+
 static int nd_pfn_init(struct nd_pfn *nd_pfn)
 {
 	u32 dax_label_reserve = is_nd_dax(&nd_pfn->dev) ? SZ_128K : 0;
 	struct nd_namespace_common *ndns = nd_pfn->ndns;
-	u32 start_pad = 0, end_trunc = 0;
+	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
 	resource_size_t start, size;
-	struct nd_namespace_io *nsio;
 	struct nd_region *nd_region;
+	u32 start_pad, end_trunc;
 	struct nd_pfn_sb *pfn_sb;
 	unsigned long npfns;
 	phys_addr_t offset;
@@ -688,30 +721,7 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn)
 
 	memset(pfn_sb, 0, sizeof(*pfn_sb));
 
-	/*
-	 * Check if pmem collides with 'System RAM' when section aligned and
-	 * trim it accordingly
-	 */
-	nsio = to_nd_namespace_io(&ndns->dev);
-	start = PHYS_SECTION_ALIGN_DOWN(nsio->res.start);
-	size = resource_size(&nsio->res);
-	if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
-				IORES_DESC_NONE) == REGION_MIXED) {
-		start = nsio->res.start;
-		start_pad = PHYS_SECTION_ALIGN_UP(start) - start;
-	}
-
-	start = nsio->res.start;
-	size = PHYS_SECTION_ALIGN_UP(start + size) - start;
-	if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
-				IORES_DESC_NONE) == REGION_MIXED
-			|| !IS_ALIGNED(start + resource_size(&nsio->res),
-				nd_pfn->align)) {
-		size = resource_size(&nsio->res);
-		end_trunc = start + size - phys_pmem_align_down(nd_pfn,
-				start + size);
-	}
-
+	trim_pfn_device(nd_pfn, &start_pad, &end_trunc);
 	if (start_pad + end_trunc)
 		dev_info(&nd_pfn->dev, "%s alignment collision, truncate %d bytes\n",
 				dev_name(&ndns->dev), start_pad + end_trunc);
@@ -722,7 +732,7 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn)
 	 * implementation will limit the pfns advertised through
 	 * ->direct_access() to those that are included in the memmap.
 	 */
-	start += start_pad;
+	start = nsio->res.start + start_pad;
 	size = resource_size(&nsio->res);
 	npfns = PFN_SECTION_ALIGN_UP((size - start_pad - end_trunc - SZ_8K)
 			/ PAGE_SIZE);
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index 174a418cb171..e7377f1028ef 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -1184,6 +1184,47 @@ int nvdimm_has_cache(struct nd_region *nd_region)
 }
 EXPORT_SYMBOL_GPL(nvdimm_has_cache);
 
+struct conflict_context {
+	struct nd_region *nd_region;
+	resource_size_t start, size;
+};
+
+static int region_conflict(struct device *dev, void *data)
+{
+	struct nd_region *nd_region;
+	struct conflict_context *ctx = data;
+	resource_size_t res_end, region_end, region_start;
+
+	if (!is_memory(dev))
+		return 0;
+
+	nd_region = to_nd_region(dev);
+	if (nd_region == ctx->nd_region)
+		return 0;
+
+	res_end = ctx->start + ctx->size;
+	region_start = nd_region->ndr_start;
+	region_end = region_start + nd_region->ndr_size;
+	if (ctx->start >= region_start && ctx->start < region_end)
+		return -EBUSY;
+	if (res_end > region_start && res_end <= region_end)
+		return -EBUSY;
+	return 0;
+}
+
+int nd_region_conflict(struct nd_region *nd_region, resource_size_t start,
+		resource_size_t size)
+{
+	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
+	struct conflict_context ctx = {
+		.nd_region = nd_region,
+		.start = start,
+		.size = size,
+	};
+
+	return device_for_each_child(&nvdimm_bus->dev, &ctx, region_conflict);
+}
+
 void __exit nd_region_devs_exit(void)
 {
 	ida_destroy(&region_ida);