cxl fixes for 6.8-rc2

- Fix unit test build regression fallout from global
   "missing-prototypes" change
 
 - Fix compatibility with devices that do not support interrupts
 
 - Fix overflow when calculating the capacity of large interleave sets
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Merge tag 'cxl-fixes-6.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl fixes from Dan Williams:
 "A build regression fix, a device compatibility fix, and an original
  bug preventing creation of large (16 device) interleave sets:

   - Fix unit test build regression fallout from global
     "missing-prototypes" change

   - Fix compatibility with devices that do not support interrupts

   - Fix overflow when calculating the capacity of large interleave sets"

* tag 'cxl-fixes-6.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
  cxl/region：Fix overflow issue in alloc_hpa()
  cxl/pci: Skip irq features if MSI/MSI-X are not supported
  tools/testing/nvdimm: Disable "missing prototypes / declarations" warnings
  tools/testing/cxl: Disable "missing prototypes / declarations" warnings

drivers/cxl/core/region.c

@@ -525,7 +525,7 @@ static int alloc_hpa(struct cxl_region *cxlr, resource_size_t size)
 	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);
 	struct cxl_region_params *p = &cxlr->params;
 	struct resource *res;
-	u32 remainder = 0;
+	u64 remainder = 0;
 
 	lockdep_assert_held_write(&cxl_region_rwsem);
 
@@ -545,7 +545,7 @@ static int alloc_hpa(struct cxl_region *cxlr, resource_size_t size)
 	    (cxlr->mode == CXL_DECODER_PMEM && uuid_is_null(&p->uuid)))
 		return -ENXIO;
 
-	div_u64_rem(size, SZ_256M * p->interleave_ways, &remainder);
+	div64_u64_rem(size, (u64)SZ_256M * p->interleave_ways, &remainder);
 	if (remainder)
 		return -EINVAL;
 

drivers/cxl/pci.c

@@ -382,7 +382,7 @@ static int cxl_pci_mbox_send(struct cxl_memdev_state *mds,
 	return rc;
 }
 
-static int cxl_pci_setup_mailbox(struct cxl_memdev_state *mds)
+static int cxl_pci_setup_mailbox(struct cxl_memdev_state *mds, bool irq_avail)
 {
 	struct cxl_dev_state *cxlds = &mds->cxlds;
 	const int cap = readl(cxlds->regs.mbox + CXLDEV_MBOX_CAPS_OFFSET);
@@ -441,7 +441,7 @@ static int cxl_pci_setup_mailbox(struct cxl_memdev_state *mds)
 	INIT_DELAYED_WORK(&mds->security.poll_dwork, cxl_mbox_sanitize_work);
 
 	/* background command interrupts are optional */
-	if (!(cap & CXLDEV_MBOX_CAP_BG_CMD_IRQ))
+	if (!(cap & CXLDEV_MBOX_CAP_BG_CMD_IRQ) || !irq_avail)
 		return 0;
 
 	msgnum = FIELD_GET(CXLDEV_MBOX_CAP_IRQ_MSGNUM_MASK, cap);
@@ -588,7 +588,7 @@ static int cxl_mem_alloc_event_buf(struct cxl_memdev_state *mds)
 	return devm_add_action_or_reset(mds->cxlds.dev, free_event_buf, buf);
 }
 
-static int cxl_alloc_irq_vectors(struct pci_dev *pdev)
+static bool cxl_alloc_irq_vectors(struct pci_dev *pdev)
 {
 	int nvecs;
 
@@ -605,9 +605,9 @@ static int cxl_alloc_irq_vectors(struct pci_dev *pdev)
 				      PCI_IRQ_MSIX | PCI_IRQ_MSI);
 	if (nvecs < 1) {
 		dev_dbg(&pdev->dev, "Failed to alloc irq vectors: %d\n", nvecs);
-		return -ENXIO;
+		return false;
 	}
-	return 0;
+	return true;
 }
 
 static irqreturn_t cxl_event_thread(int irq, void *id)
@@ -743,7 +743,7 @@ static bool cxl_event_int_is_fw(u8 setting)
 }
 
 static int cxl_event_config(struct pci_host_bridge *host_bridge,
-			    struct cxl_memdev_state *mds)
+			    struct cxl_memdev_state *mds, bool irq_avail)
 {
 	struct cxl_event_interrupt_policy policy;
 	int rc;
@@ -755,6 +755,11 @@ static int cxl_event_config(struct pci_host_bridge *host_bridge,
 	if (!host_bridge->native_cxl_error)
 		return 0;
 
+	if (!irq_avail) {
+		dev_info(mds->cxlds.dev, "No interrupt support, disable event processing.\n");
+		return 0;
+	}
+
 	rc = cxl_mem_alloc_event_buf(mds);
 	if (rc)
 		return rc;
@@ -789,6 +794,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	struct cxl_register_map map;
 	struct cxl_memdev *cxlmd;
 	int i, rc, pmu_count;
+	bool irq_avail;
 
 	/*
 	 * Double check the anonymous union trickery in struct cxl_regs
@@ -846,11 +852,9 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	else
 		dev_warn(&pdev->dev, "Media not active (%d)\n", rc);
 
-	rc = cxl_alloc_irq_vectors(pdev);
-	if (rc)
-		return rc;
+	irq_avail = cxl_alloc_irq_vectors(pdev);
 
-	rc = cxl_pci_setup_mailbox(mds);
+	rc = cxl_pci_setup_mailbox(mds, irq_avail);
 	if (rc)
 		return rc;
 
@@ -909,7 +913,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 		}
 	}
 
-	rc = cxl_event_config(host_bridge, mds);
+	rc = cxl_event_config(host_bridge, mds, irq_avail);
 	if (rc)
 		return rc;
 

tools/testing/cxl/Kbuild

@@ -65,4 +65,6 @@ cxl_core-y += config_check.o
 cxl_core-y += cxl_core_test.o
 cxl_core-y += cxl_core_exports.o
 
+KBUILD_CFLAGS := $(filter-out -Wmissing-prototypes -Wmissing-declarations, $(KBUILD_CFLAGS))
+
 obj-m += test/

tools/testing/cxl/test/Kbuild

@@ -8,3 +8,5 @@ obj-m += cxl_mock_mem.o
 cxl_test-y := cxl.o
 cxl_mock-y := mock.o
 cxl_mock_mem-y := mem.o
+
+KBUILD_CFLAGS := $(filter-out -Wmissing-prototypes -Wmissing-declarations, $(KBUILD_CFLAGS))

tools/testing/nvdimm/Kbuild

@@ -82,4 +82,6 @@ libnvdimm-$(CONFIG_NVDIMM_KEYS) += $(NVDIMM_SRC)/security.o
 libnvdimm-y += libnvdimm_test.o
 libnvdimm-y += config_check.o
 
+KBUILD_CFLAGS := $(filter-out -Wmissing-prototypes -Wmissing-declarations, $(KBUILD_CFLAGS))
+
 obj-m += test/