On 09/06/2018 01:50, Dan Williams wrote: > Define a local 'vma' variable rather than repetitively de-referencing > the passed in 'struct vm_fault *' instance.
Hi Dan, Why is this needed ? I can't see the real benefit, having the vma deferenced from the vm_fault structure is not obfuscating the code and it eases to follow the use of vmf->vma. Am I missing something ? Cheers, Laurent. > > Signed-off-by: Dan Williams <[email protected]> > --- > drivers/dax/device.c | 30 ++++++++++++++++-------------- > 1 file changed, 16 insertions(+), 14 deletions(-) > > diff --git a/drivers/dax/device.c b/drivers/dax/device.c > index d44d98c54d0f..686de08e120b 100644 > --- a/drivers/dax/device.c > +++ b/drivers/dax/device.c > @@ -247,13 +247,14 @@ __weak phys_addr_t dax_pgoff_to_phys(struct dev_dax > *dev_dax, pgoff_t pgoff, > static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax, > struct vm_fault *vmf) > { > + struct vm_area_struct *vma = vmf->vma; > struct device *dev = &dev_dax->dev; > struct dax_region *dax_region; > phys_addr_t phys; > pfn_t pfn; > unsigned int fault_size = PAGE_SIZE; > > - if (check_vma(dev_dax, vmf->vma, __func__)) > + if (check_vma(dev_dax, vma, __func__)) > return VM_FAULT_SIGBUS; > > dax_region = dev_dax->region; > @@ -274,13 +275,14 @@ static vm_fault_t __dev_dax_pte_fault(struct dev_dax > *dev_dax, > > pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); > > - return vmf_insert_mixed(vmf->vma, vmf->address, pfn); > + return vmf_insert_mixed(vma, vmf->address, pfn); > } > > 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 vm_area_struct *vma = vmf->vma; > struct device *dev = &dev_dax->dev; > struct dax_region *dax_region; > phys_addr_t phys; > @@ -288,7 +290,7 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax > *dev_dax, > pfn_t pfn; > unsigned int fault_size = PMD_SIZE; > > - if (check_vma(dev_dax, vmf->vma, __func__)) > + if (check_vma(dev_dax, vma, __func__)) > return VM_FAULT_SIGBUS; > > dax_region = dev_dax->region; > @@ -310,11 +312,10 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax > *dev_dax, > 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) > + if (pmd_addr < vma->vm_start || (pmd_addr + PMD_SIZE) > vma->vm_end) > return VM_FAULT_SIGBUS; > > - pgoff = linear_page_index(vmf->vma, pmd_addr); > + pgoff = linear_page_index(vma, pmd_addr); > phys = dax_pgoff_to_phys(dev_dax, pgoff, PMD_SIZE); > if (phys == -1) { > dev_dbg(dev, "pgoff_to_phys(%#lx) failed\n", pgoff); > @@ -323,7 +324,7 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax > *dev_dax, > > pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); > > - return vmf_insert_pfn_pmd(vmf->vma, vmf->address, vmf->pmd, pfn, > + return vmf_insert_pfn_pmd(vma, vmf->address, vmf->pmd, pfn, > vmf->flags & FAULT_FLAG_WRITE); > } > > @@ -332,6 +333,7 @@ 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 vm_area_struct *vma = vmf->vma; > struct device *dev = &dev_dax->dev; > struct dax_region *dax_region; > phys_addr_t phys; > @@ -340,7 +342,7 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax > *dev_dax, > unsigned int fault_size = PUD_SIZE; > > > - if (check_vma(dev_dax, vmf->vma, __func__)) > + if (check_vma(dev_dax, vma, __func__)) > return VM_FAULT_SIGBUS; > > dax_region = dev_dax->region; > @@ -362,11 +364,10 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax > *dev_dax, > 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) > + if (pud_addr < vma->vm_start || (pud_addr + PUD_SIZE) > vma->vm_end) > return VM_FAULT_SIGBUS; > > - pgoff = linear_page_index(vmf->vma, pud_addr); > + pgoff = linear_page_index(vma, pud_addr); > phys = dax_pgoff_to_phys(dev_dax, pgoff, PUD_SIZE); > if (phys == -1) { > dev_dbg(dev, "pgoff_to_phys(%#lx) failed\n", pgoff); > @@ -375,7 +376,7 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax > *dev_dax, > > pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); > > - return vmf_insert_pfn_pud(vmf->vma, vmf->address, vmf->pud, pfn, > + return vmf_insert_pfn_pud(vma, vmf->address, vmf->pud, pfn, > vmf->flags & FAULT_FLAG_WRITE); > } > #else > @@ -390,12 +391,13 @@ static vm_fault_t dev_dax_huge_fault(struct vm_fault > *vmf, > enum page_entry_size pe_size) > { > int rc, id; > - struct file *filp = vmf->vma->vm_file; > + struct vm_area_struct *vma = vmf->vma; > + struct file *filp = vma->vm_file; > struct dev_dax *dev_dax = filp->private_data; > > dev_dbg(&dev_dax->dev, "%s: %s (%#lx - %#lx) size = %d\n", > current->comm, > (vmf->flags & FAULT_FLAG_WRITE) ? "write" : "read", > - vmf->vma->vm_start, vmf->vma->vm_end, pe_size); > + vma->vm_start, vma->vm_end, pe_size); > > id = dax_read_lock(); > switch (pe_size) { > _______________________________________________ Linux-nvdimm mailing list [email protected] https://lists.01.org/mailman/listinfo/linux-nvdimm
