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device-dax: set mapping prior to vmf_insert_pfn{,_pmd,pud}()

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Normally, the @page mapping is set prior to inserting the page into a
page table entry.  Make device-dax adhere to the same ordering, rather
than setting mapping after the PTE is inserted.

The address_space never changes and it is always associated with the
same inode and underlying pages.  So, the page mapping is set once but
cleared when the struct pages are removed/freed (i.e.  after
{devm_}memunmap_pages()).

Link: https://lkml.kernel.org/r/20211202204422.26777-10-joao.m.martins@oracle.com
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Joao Martins 2022-01-14 14:04:40 -08:00 committed by Linus Torvalds
parent a0fb038e50
commit 0e7325f03f
1 changed files with 6 additions and 6 deletions
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12
drivers/dax/device.c
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@ -121,6 +121,8 @@ static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax,
*pfn = phys_to_pfn_t(phys, PFN_DEV|PFN_MAP);
dax_set_mapping(vmf, *pfn, fault_size);
return vmf_insert_mixed(vmf->vma, vmf->address, *pfn);
}
@ -161,6 +163,8 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax,
*pfn = phys_to_pfn_t(phys, PFN_DEV|PFN_MAP);
dax_set_mapping(vmf, *pfn, fault_size);
return vmf_insert_pfn_pmd(vmf, *pfn, vmf->flags & FAULT_FLAG_WRITE);
}
@ -203,6 +207,8 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax,
*pfn = phys_to_pfn_t(phys, PFN_DEV|PFN_MAP);
dax_set_mapping(vmf, *pfn, fault_size);
return vmf_insert_pfn_pud(vmf, *pfn, vmf->flags & FAULT_FLAG_WRITE);
}
#else
@ -217,7 +223,6 @@ static vm_fault_t dev_dax_huge_fault(struct vm_fault *vmf,
enum page_entry_size pe_size)
{
struct file *filp = vmf->vma->vm_file;
unsigned long fault_size;
vm_fault_t rc = VM_FAULT_SIGBUS;
int id;
pfn_t pfn;
@ -230,23 +235,18 @@ static vm_fault_t dev_dax_huge_fault(struct vm_fault *vmf,
id = dax_read_lock();
switch (pe_size) {
case PE_SIZE_PTE:
fault_size = PAGE_SIZE;
rc = __dev_dax_pte_fault(dev_dax, vmf, &pfn);
break;
case PE_SIZE_PMD:
fault_size = PMD_SIZE;
rc = __dev_dax_pmd_fault(dev_dax, vmf, &pfn);
break;
case PE_SIZE_PUD:
fault_size = PUD_SIZE;
rc = __dev_dax_pud_fault(dev_dax, vmf, &pfn);
break;
default:
rc = VM_FAULT_SIGBUS;
}
if (rc == VM_FAULT_NOPAGE)
dax_set_mapping(vmf, pfn, fault_size);
dax_read_unlock(id);
return rc;