Commit 1b8df619 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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

Pull device-dax fixes from Dan Williams:
 "The device-dax driver was not being careful to handle falling back to
  smaller fault-granularity sizes.

  The driver already fails fault attempts that are smaller than the
  device's alignment, but it also needs to handle the cases where a
  larger page mapping could be established. For simplicity of the
  immediate fix the implementation just signals VM_FAULT_FALLBACK until
  fault-size == device-alignment.

  One fix is for -stable to address pmd-to-pte fallback from the
  original implementation, another fix is for the new (introduced in
  4.11-rc1) pud-to-pmd regression, and a typo fix comes along for the
  ride.

  These have received a build success notification from the kbuild
  robot"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  device-dax: fix debug output typo
  device-dax: fix pud fault fallback handling
  device-dax: fix pmd/pte fault fallback handling
parents 93afaa45 52084f89

drivers/dax/dax.c

+30 −3
Original line number Diff line number Diff line
@@ -427,6 +427,7 @@ static int __dax_dev_pte_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) 
	int rc = VM_FAULT_SIGBUS;

	phys_addr_t phys;

	pfn_t pfn;

	unsigned int fault_size = PAGE_SIZE;



	if (check_vma(dax_dev, vmf->vma, __func__))

		return VM_FAULT_SIGBUS;
@@ -437,9 +438,12 @@ static int __dax_dev_pte_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) 
		return VM_FAULT_SIGBUS;

	}



	if (fault_size != dax_region->align)

		return VM_FAULT_SIGBUS;



	phys = pgoff_to_phys(dax_dev, vmf->pgoff, PAGE_SIZE);

	if (phys == -1) {

		dev_dbg(dev, "%s: phys_to_pgoff(%#lx) failed\n", __func__,

		dev_dbg(dev, "%s: pgoff_to_phys(%#lx) failed\n", __func__,

				vmf->pgoff);

		return VM_FAULT_SIGBUS;

	}
@@ -464,6 +468,7 @@ static int __dax_dev_pmd_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) 
	phys_addr_t phys;

	pgoff_t pgoff;

	pfn_t pfn;

	unsigned int fault_size = PMD_SIZE;



	if (check_vma(dax_dev, vmf->vma, __func__))

		return VM_FAULT_SIGBUS;
@@ -480,10 +485,20 @@ static int __dax_dev_pmd_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) 
		return VM_FAULT_SIGBUS;

	}



	if (fault_size < dax_region->align)

		return VM_FAULT_SIGBUS;

	else if (fault_size > dax_region->align)

		return VM_FAULT_FALLBACK;



	/* if we are outside of the VMA */

	if (pmd_addr < vmf->vma->vm_start ||

			(pmd_addr + PMD_SIZE) > vmf->vma->vm_end)

		return VM_FAULT_SIGBUS;



	pgoff = linear_page_index(vmf->vma, pmd_addr);

	phys = pgoff_to_phys(dax_dev, pgoff, PMD_SIZE);

	if (phys == -1) {

		dev_dbg(dev, "%s: phys_to_pgoff(%#lx) failed\n", __func__,

		dev_dbg(dev, "%s: pgoff_to_phys(%#lx) failed\n", __func__,

				pgoff);

		return VM_FAULT_SIGBUS;

	}
@@ -503,6 +518,8 @@ static int __dax_dev_pud_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) 
	phys_addr_t phys;

	pgoff_t pgoff;

	pfn_t pfn;

	unsigned int fault_size = PUD_SIZE;





	if (check_vma(dax_dev, vmf->vma, __func__))

		return VM_FAULT_SIGBUS;
@@ -519,10 +536,20 @@ static int __dax_dev_pud_fault(struct dax_dev *dax_dev, struct vm_fault *vmf) 
		return VM_FAULT_SIGBUS;

	}



	if (fault_size < dax_region->align)

		return VM_FAULT_SIGBUS;

	else if (fault_size > dax_region->align)

		return VM_FAULT_FALLBACK;



	/* if we are outside of the VMA */

	if (pud_addr < vmf->vma->vm_start ||

			(pud_addr + PUD_SIZE) > vmf->vma->vm_end)

		return VM_FAULT_SIGBUS;



	pgoff = linear_page_index(vmf->vma, pud_addr);

	phys = pgoff_to_phys(dax_dev, pgoff, PUD_SIZE);

	if (phys == -1) {

		dev_dbg(dev, "%s: phys_to_pgoff(%#lx) failed\n", __func__,

		dev_dbg(dev, "%s: pgoff_to_phys(%#lx) failed\n", __func__,

				pgoff);

		return VM_FAULT_SIGBUS;

	}

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