struct inode *inode;
BUG_ON(!PageLocked(page));
+ /*
+ * shmem_backing_dev_info's capabilities prevent regular writeback or
+ * sync from ever calling shmem_writepage; but a stacking filesystem
+ * may use the ->writepage of its underlying filesystem, in which case
+ * we want to do nothing when that underlying filesystem is tmpfs
+ * (writing out to swap is useful as a response to memory pressure, but
+ * of no use to stabilize the data) - just redirty the page, unlock it
+ * and claim success in this case. AOP_WRITEPAGE_ACTIVATE, and the
+ * page_mapped check below, must be avoided unless we're in reclaim.
+ */
+ if (!wbc->for_reclaim) {
+ set_page_dirty(page);
+ unlock_page(page);
+ return 0;
+ }
BUG_ON(page_mapped(page));
mapping = page->mapping;
pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, idx);
pvma.vm_pgoff = idx;
pvma.vm_end = PAGE_SIZE;
- page = alloc_page_vma(gfp | __GFP_ZERO, &pvma, 0);
+ page = alloc_page_vma(gfp, &pvma, 0);
mpol_free(pvma.vm_policy);
return page;
}
static inline struct page *
shmem_alloc_page(gfp_t gfp,struct shmem_inode_info *info, unsigned long idx)
{
- return alloc_page(gfp | __GFP_ZERO);
+ return alloc_page(gfp);
}
#endif
info->alloced++;
spin_unlock(&info->lock);
+ clear_highpage(filepage);
flush_dcache_page(filepage);
SetPageUptodate(filepage);
}
return 1;
}
-static struct export_operations shmem_export_ops = {
+static const struct export_operations shmem_export_ops = {
.get_parent = shmem_get_parent,
.encode_fh = shmem_encode_fh,
.fh_to_dentry = shmem_fh_to_dentry,