[PATCH v3] dax: Change return type to vm_fault_t

Use new return type vm_fault_t for fault and huge_fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Reference id -> 1c8f422059ae ("mm: change return type to vm_fault_t") Previously vm_insert_mixed() returns err which driver mapped into VM_FAULT_* type. The new function vmf_insert_mixed() will replace this inefficiency by returning VM_FAULT_* type. Signed-off-by: Souptick Joarder <jrdr.linux(a)gmail.com&gt; Reviewed-by: Matthew Wilcox <mawilcox(a)microsoft.com&gt; Reviewed-by: Ross Zwisler <ross.zwisler(a)linux.intel.com&gt; --- v2: Modified the change log v3: Updated the change log and added Ross in review list drivers/dax/device.c | 26 +++++++++++--------------- 1 file changed, 11 insertions(+), 15 deletions(-) diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 2137dbc..a122701 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -243,11 +243,11 @@ __weak phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, return -1; } -static int __dev_dax_pte_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) +static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax, + struct vm_fault *vmf) { struct device *dev = &dev_dax->dev; struct dax_region *dax_region; - int rc = VM_FAULT_SIGBUS; phys_addr_t phys; pfn_t pfn; unsigned int fault_size = PAGE_SIZE; @@ -274,17 +274,11 @@ static int __dev_dax_pte_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); - rc = vm_insert_mixed(vmf->vma, vmf->address, pfn); - - if (rc == -ENOMEM) - return VM_FAULT_OOM; - if (rc < 0 && rc != -EBUSY) - return VM_FAULT_SIGBUS; - - return VM_FAULT_NOPAGE; + return vmf_insert_mixed(vmf->vma, vmf->address, pfn); } -static int __dev_dax_pmd_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) +static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax, + struct vm_fault *vmf) { unsigned long pmd_addr = vmf->address & PMD_MASK; struct device *dev = &dev_dax->dev; @@ -335,7 +329,8 @@ static int __dev_dax_pmd_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) } #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD -static int __dev_dax_pud_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) +static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax, + struct vm_fault *vmf) { unsigned long pud_addr = vmf->address & PUD_MASK; struct device *dev = &dev_dax->dev; @@ -386,13 +381,14 @@ static int __dev_dax_pud_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) vmf->flags & FAULT_FLAG_WRITE); } #else -static int __dev_dax_pud_fault(struct dev_dax *dev_dax, struct vm_fault *vmf) +static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax, + struct vm_fault *vmf) { return VM_FAULT_FALLBACK; } #endif /* !CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ -static int dev_dax_huge_fault(struct vm_fault *vmf, +static vm_fault_t dev_dax_huge_fault(struct vm_fault *vmf, enum page_entry_size pe_size) { int rc, id; @@ -423,7 +419,7 @@ static int dev_dax_huge_fault(struct vm_fault *vmf, return rc; } -static int dev_dax_fault(struct vm_fault *vmf) +static vm_fault_t dev_dax_fault(struct vm_fault *vmf) { return dev_dax_huge_fault(vmf, PE_SIZE_PTE); } -- 1.9.1