Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm fixes from Dan Williams:

 - Four fixes for "flush hint" support.

   Flush hints are addresses advertised by the ACPI 6+ NFIT (NVDIMM
   Firmware Interface Table) that when written and fenced guarantee that
   writes pending in platform write buffers (outside the cpu) have been
   flushed to media.  They might also be used by hypervisors as a
   trigger condition to flush guest-persistent memory ranges to storage.

    Fix a potential data corruption issue, a broken definition of the
    hint array, a wrong allocation size for the unit test implementation
    of the flush hint table, and missing NULL check in an error path.

    The unit test, while it did not prevent these bugs from being
    merged, at least triggered occasional crashes in advance of
    production usages.

 - Fix handling of ACPI DSM error status results.  The DSM mechanism
   allows communication with platform and memory device firmware.  We
   correctly parse known errors, but were silently ignoring others.

   Fix it to consistently fail any command with a non-zero status return
   that we otherwise do not interpret / handle.

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm, region: fix flush hint table thinko
  nfit: fail DSMs that return non-zero status by default
  libnvdimm: fix devm_nvdimm_memremap() error path
  tools/testing/nvdimm: fix allocation range for mock flush hint tables
  nvdimm: fix PHYS_PFN/PFN_PHYS mixup

4 files changed, 68 insertions, 32 deletions

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 80cc7c089a15..e1d5ea6d5e40 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -94,54 +94,50 @@ static struct acpi_device *to_acpi_dev(struct acpi_nfit_desc *acpi_desc)
 	return to_acpi_device(acpi_desc->dev);
 }
 
-static int xlat_status(void *buf, unsigned int cmd)
+static int xlat_status(void *buf, unsigned int cmd, u32 status)
 {
 	struct nd_cmd_clear_error *clear_err;
 	struct nd_cmd_ars_status *ars_status;
-	struct nd_cmd_ars_start *ars_start;
-	struct nd_cmd_ars_cap *ars_cap;
 	u16 flags;
 
 	switch (cmd) {
 	case ND_CMD_ARS_CAP:
-		ars_cap = buf;
-		if ((ars_cap->status & 0xffff) == NFIT_ARS_CAP_NONE)
+		if ((status & 0xffff) == NFIT_ARS_CAP_NONE)
 			return -ENOTTY;
 
 		/* Command failed */
-		if (ars_cap->status & 0xffff)
+		if (status & 0xffff)
 			return -EIO;
 
 		/* No supported scan types for this range */
 		flags = ND_ARS_PERSISTENT | ND_ARS_VOLATILE;
-		if ((ars_cap->status >> 16 & flags) == 0)
+		if ((status >> 16 & flags) == 0)
 			return -ENOTTY;
 		break;
 	case ND_CMD_ARS_START:
-		ars_start = buf;
 		/* ARS is in progress */
-		if ((ars_start->status & 0xffff) == NFIT_ARS_START_BUSY)
+		if ((status & 0xffff) == NFIT_ARS_START_BUSY)
 			return -EBUSY;
 
 		/* Command failed */
-		if (ars_start->status & 0xffff)
+		if (status & 0xffff)
 			return -EIO;
 		break;
 	case ND_CMD_ARS_STATUS:
 		ars_status = buf;
 		/* Command failed */
-		if (ars_status->status & 0xffff)
+		if (status & 0xffff)
 			return -EIO;
 		/* Check extended status (Upper two bytes) */
-		if (ars_status->status == NFIT_ARS_STATUS_DONE)
+		if (status == NFIT_ARS_STATUS_DONE)
 			return 0;
 
 		/* ARS is in progress */
-		if (ars_status->status == NFIT_ARS_STATUS_BUSY)
+		if (status == NFIT_ARS_STATUS_BUSY)
 			return -EBUSY;
 
 		/* No ARS performed for the current boot */
-		if (ars_status->status == NFIT_ARS_STATUS_NONE)
+		if (status == NFIT_ARS_STATUS_NONE)
 			return -EAGAIN;
 
 		/*
@@ -149,19 +145,19 @@ static int xlat_status(void *buf, unsigned int cmd)
 		 * agent wants the scan to stop.  If we didn't overflow
 		 * then just continue with the returned results.
 		 */
-		if (ars_status->status == NFIT_ARS_STATUS_INTR) {
+		if (status == NFIT_ARS_STATUS_INTR) {
 			if (ars_status->flags & NFIT_ARS_F_OVERFLOW)
 				return -ENOSPC;
 			return 0;
 		}
 
 		/* Unknown status */
-		if (ars_status->status >> 16)
+		if (status >> 16)
 			return -EIO;
 		break;
 	case ND_CMD_CLEAR_ERROR:
 		clear_err = buf;
-		if (clear_err->status & 0xffff)
+		if (status & 0xffff)
 			return -EIO;
 		if (!clear_err->cleared)
 			return -EIO;
@@ -172,6 +168,9 @@ static int xlat_status(void *buf, unsigned int cmd)
 		break;
 	}
 
+	/* all other non-zero status results in an error */
+	if (status)
+		return -EIO;
 	return 0;
 }
 
@@ -186,10 +185,10 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
 	struct nd_cmd_pkg *call_pkg = NULL;
 	const char *cmd_name, *dimm_name;
 	unsigned long cmd_mask, dsm_mask;
+	u32 offset, fw_status = 0;
 	acpi_handle handle;
 	unsigned int func;
 	const u8 *uuid;
-	u32 offset;
 	int rc, i;
 
 	func = cmd;
@@ -317,6 +316,15 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
 				out_obj->buffer.pointer + offset, out_size);
 		offset += out_size;
 	}
+
+	/*
+	 * Set fw_status for all the commands with a known format to be
+	 * later interpreted by xlat_status().
+	 */
+	if (i >= 1 && ((cmd >= ND_CMD_ARS_CAP && cmd <= ND_CMD_CLEAR_ERROR)
+			|| (cmd >= ND_CMD_SMART && cmd <= ND_CMD_VENDOR)))
+		fw_status = *(u32 *) out_obj->buffer.pointer;
+
 	if (offset + in_buf.buffer.length < buf_len) {
 		if (i >= 1) {
 			/*
@@ -325,7 +333,7 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
 			 */
 			rc = buf_len - offset - in_buf.buffer.length;
 			if (cmd_rc)
-				*cmd_rc = xlat_status(buf, cmd);
+				*cmd_rc = xlat_status(buf, cmd, fw_status);
 		} else {
 			dev_err(dev, "%s:%s underrun cmd: %s buf_len: %d out_len: %d\n",
 					__func__, dimm_name, cmd_name, buf_len,
@@ -335,7 +343,7 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
 	} else {
 		rc = 0;
 		if (cmd_rc)
-			*cmd_rc = xlat_status(buf, cmd);
+			*cmd_rc = xlat_status(buf, cmd, fw_status);
 	}
 
  out:
diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index 715583f69d28..4d7bbd2df5c0 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -99,8 +99,11 @@ static struct nvdimm_map *alloc_nvdimm_map(struct device *dev,
 	nvdimm_map->size = size;
 	kref_init(&nvdimm_map->kref);
 
-	if (!request_mem_region(offset, size, dev_name(&nvdimm_bus->dev)))
+	if (!request_mem_region(offset, size, dev_name(&nvdimm_bus->dev))) {
+		dev_err(&nvdimm_bus->dev, "failed to request %pa + %zd for %s\n",
+				&offset, size, dev_name(dev));
 		goto err_request_region;
+	}
 
 	if (flags)
 		nvdimm_map->mem = memremap(offset, size, flags);
@@ -171,6 +174,9 @@ void *devm_nvdimm_memremap(struct device *dev, resource_size_t offset,
 		kref_get(&nvdimm_map->kref);
 	nvdimm_bus_unlock(dev);
 
+	if (!nvdimm_map)
+		return NULL;
+
 	if (devm_add_action_or_reset(dev, nvdimm_map_put, nvdimm_map))
 		return NULL;
 
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 e8d5ba7b29af..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,
-					PHYS_PFN(pfn), PAGE_SIZE);
+					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;
 
 	/*