return ret;
}
-/*
- * Invalidate exceptional DAX entry if easily possible. This handles DAX
- * entries for invalidate_inode_pages() so we evict the entry only if we can
- * do so without blocking.
- */
-int dax_invalidate_mapping_entry(struct address_space *mapping, pgoff_t index)
-{
- int ret = 0;
- void *entry, **slot;
- struct radix_tree_root *page_tree = &mapping->page_tree;
-
- spin_lock_irq(&mapping->tree_lock);
- entry = __radix_tree_lookup(page_tree, index, NULL, &slot);
- if (!entry || !radix_tree_exceptional_entry(entry) ||
- slot_locked(mapping, slot))
- goto out;
- if (radix_tree_tag_get(page_tree, index, PAGECACHE_TAG_DIRTY) ||
- radix_tree_tag_get(page_tree, index, PAGECACHE_TAG_TOWRITE))
- goto out;
- radix_tree_delete(page_tree, index);
- mapping->nrexceptional--;
- ret = 1;
-out:
- spin_unlock_irq(&mapping->tree_lock);
- if (ret)
- dax_wake_mapping_entry_waiter(mapping, index, entry, true);
- return ret;
-}
-
/*
* Invalidate exceptional DAX entry if it is clean.
*/
void *kaddr;
pfn_t pfn;
- rc = bdev_dax_pgoff(bdev, sector, size, &pgoff);
+ rc = bdev_dax_pgoff(bdev, sector, PAGE_SIZE, &pgoff);
if (rc)
return rc;
id = dax_read_lock();
- rc = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size), &kaddr,
+ rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr,
&pfn);
if (rc < 0) {
dax_read_unlock(id);
* into page tables. We have to tear down these mappings so that data
* written by write(2) is visible in mmap.
*/
- if ((iomap->flags & IOMAP_F_NEW) && inode->i_mapping->nrpages) {
+ if (iomap->flags & IOMAP_F_NEW) {
invalidate_inode_pages2_range(inode->i_mapping,
pos >> PAGE_SHIFT,
(end - 1) >> PAGE_SHIFT);
if ((vmf->flags & FAULT_FLAG_WRITE) && !vmf->cow_page)
flags |= IOMAP_WRITE;
+ entry = grab_mapping_entry(mapping, vmf->pgoff, 0);
+ if (IS_ERR(entry)) {
+ vmf_ret = dax_fault_return(PTR_ERR(entry));
+ goto out;
+ }
+
+ /*
+ * 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
error = ops->iomap_begin(inode, pos, PAGE_SIZE, flags, &iomap);
if (error) {
vmf_ret = dax_fault_return(error);
- goto out;
+ goto unlock_entry;
}
if (WARN_ON_ONCE(iomap.offset + iomap.length < pos + PAGE_SIZE)) {
- vmf_ret = dax_fault_return(-EIO); /* fs corruption? */
- goto finish_iomap;
- }
-
- entry = grab_mapping_entry(mapping, vmf->pgoff, 0);
- if (IS_ERR(entry)) {
- vmf_ret = dax_fault_return(PTR_ERR(entry));
- goto finish_iomap;
+ error = -EIO; /* fs corruption? */
+ goto error_finish_iomap;
}
sector = dax_iomap_sector(&iomap, pos);
}
if (error)
- goto error_unlock_entry;
+ goto error_finish_iomap;
__SetPageUptodate(vmf->cow_page);
vmf_ret = finish_fault(vmf);
if (!vmf_ret)
vmf_ret = VM_FAULT_DONE_COW;
- goto unlock_entry;
+ goto finish_iomap;
}
switch (iomap.type) {
case IOMAP_HOLE:
if (!(vmf->flags & FAULT_FLAG_WRITE)) {
vmf_ret = dax_load_hole(mapping, &entry, vmf);
- goto unlock_entry;
+ goto finish_iomap;
}
/*FALLTHRU*/
default:
break;
}
- error_unlock_entry:
+ error_finish_iomap:
vmf_ret = dax_fault_return(error) | major;
- unlock_entry:
- put_locked_mapping_entry(mapping, vmf->pgoff, entry);
finish_iomap:
if (ops->iomap_end) {
int copied = PAGE_SIZE;
*/
ops->iomap_end(inode, pos, PAGE_SIZE, copied, flags, &iomap);
}
-out:
+ unlock_entry:
+ put_locked_mapping_entry(mapping, vmf->pgoff, entry);
+ out:
trace_dax_pte_fault_done(inode, vmf, vmf_ret);
return vmf_ret;
}
if ((pgoff | PG_PMD_COLOUR) > max_pgoff)
goto fallback;
+ /*
+ * grab_mapping_entry() will make sure we get a 2M empty entry, a DAX
+ * PMD or a HZP entry. If it can't (because a 4k page is already in
+ * the tree, for instance), it will return -EEXIST and we just fall
+ * back to 4k entries.
+ */
+ entry = grab_mapping_entry(mapping, pgoff, RADIX_DAX_PMD);
+ if (IS_ERR(entry))
+ 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
pos = (loff_t)pgoff << PAGE_SHIFT;
error = ops->iomap_begin(inode, pos, PMD_SIZE, iomap_flags, &iomap);
if (error)
- goto fallback;
+ goto unlock_entry;
if (iomap.offset + iomap.length < pos + PMD_SIZE)
goto finish_iomap;
- /*
- * grab_mapping_entry() will make sure we get a 2M empty entry, a DAX
- * PMD or a HZP entry. If it can't (because a 4k page is already in
- * the tree, for instance), it will return -EEXIST and we just fall
- * back to 4k entries.
- */
- entry = grab_mapping_entry(mapping, pgoff, RADIX_DAX_PMD);
- if (IS_ERR(entry))
- goto finish_iomap;
-
switch (iomap.type) {
case IOMAP_MAPPED:
result = dax_pmd_insert_mapping(vmf, &iomap, pos, &entry);
case IOMAP_UNWRITTEN:
case IOMAP_HOLE:
if (WARN_ON_ONCE(write))
- goto unlock_entry;
+ break;
result = dax_pmd_load_hole(vmf, &iomap, &entry);
break;
default:
break;
}
- unlock_entry:
- put_locked_mapping_entry(mapping, pgoff, entry);
finish_iomap:
if (ops->iomap_end) {
int copied = PMD_SIZE;
ops->iomap_end(inode, pos, PMD_SIZE, copied, iomap_flags,
&iomap);
}
+ unlock_entry:
+ put_locked_mapping_entry(mapping, pgoff, entry);
fallback:
if (result == VM_FAULT_FALLBACK) {
split_huge_pmd(vma, vmf->pmd, vmf->address);
projects / karo-tx-linux.git / blobdiff