diff options
| -rw-r--r-- | fs/dax.c | 23 |
1 files changed, 23 insertions, 0 deletions
@@ -1155,6 +1155,17 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf, } /* + * It is possible, particularly with mixed reads & writes to private + * mappings, that we have raced with a PMD fault that overlaps with + * the PTE we need to set up. If so just return and the fault will be + * retried. + */ + if (pmd_trans_huge(*vmf->pmd) || pmd_devmap(*vmf->pmd)) { + vmf_ret = VM_FAULT_NOPAGE; + goto unlock_entry; + } + + /* * Note that we don't bother to use iomap_apply here: DAX required * the file system block size to be equal the page size, which means * that we never have to deal with more than a single extent here. @@ -1398,6 +1409,18 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf, goto fallback; /* + * It is possible, particularly with mixed reads & writes to private + * mappings, that we have raced with a PTE fault that overlaps with + * the PMD we need to set up. If so just return and the fault will be + * retried. + */ + if (!pmd_none(*vmf->pmd) && !pmd_trans_huge(*vmf->pmd) && + !pmd_devmap(*vmf->pmd)) { + result = 0; + goto unlock_entry; + } + + /* * Note that we don't use iomap_apply here. We aren't doing I/O, only * setting up a mapping, so really we're using iomap_begin() as a way * to look up our filesystem block. |