if (unlikely(IS_ERR(page))) {
if (PTR_ERR(page) == -ENODATA) {
/* sparse */
- page = virt_to_page(empty_zero_page);
+ page = ZERO_PAGE(0);
} else {
desc->error = PTR_ERR(page);
goto out;
}
- } else
- BUG_ON(!PageUptodate(page));
+ }
/* If users can be writing to this page using arbitrary
* virtual addresses, take care about potential aliasing
flush_dcache_page(page);
/*
- * Ok, we have the page, and it's up-to-date, so
- * now we can copy it to user space...
+ * Ok, we have the page, so now we can copy it to user space...
*
* The actor routine returns how many bytes were actually used..
* NOTE! This may not be the same as how much of a user buffer
* xip_write
*
* This function walks all vmas of the address_space and unmaps the
- * empty_zero_page when found at pgoff. Should it go in rmap.c?
+ * ZERO_PAGE when found at pgoff. Should it go in rmap.c?
*/
static void
__xip_unmap (struct address_space * mapping,
unsigned long address;
pte_t *pte;
pte_t pteval;
+ spinlock_t *ptl;
+ struct page *page;
spin_lock(&mapping->i_mmap_lock);
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
address = vma->vm_start +
((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
BUG_ON(address < vma->vm_start || address >= vma->vm_end);
- /*
- * We need the page_table_lock to protect us from page faults,
- * munmap, fork, etc...
- */
- pte = page_check_address(virt_to_page(empty_zero_page), mm,
- address);
- if (!IS_ERR(pte)) {
+ page = ZERO_PAGE(address);
+ pte = page_check_address(page, mm, address, &ptl);
+ if (pte) {
/* Nuke the page table entry. */
flush_cache_page(vma, address, pte_pfn(*pte));
pteval = ptep_clear_flush(vma, address, pte);
+ page_remove_rmap(page);
+ dec_mm_counter(mm, file_rss);
BUG_ON(pte_dirty(pteval));
- pte_unmap(pte);
- spin_unlock(&mm->page_table_lock);
+ pte_unmap_unlock(pte, ptl);
+ page_cache_release(page);
}
}
spin_unlock(&mapping->i_mmap_lock);
page = mapping->a_ops->get_xip_page(mapping, pgoff*(PAGE_SIZE/512), 0);
if (!IS_ERR(page)) {
- BUG_ON(!PageUptodate(page));
- return page;
+ goto out;
}
if (PTR_ERR(page) != -ENODATA)
return NULL;
pgoff*(PAGE_SIZE/512), 1);
if (IS_ERR(page))
return NULL;
- BUG_ON(!PageUptodate(page));
/* unmap page at pgoff from all other vmas */
__xip_unmap(mapping, pgoff);
} else {
- /* not shared and writable, use empty_zero_page */
- page = virt_to_page(empty_zero_page);
+ /* not shared and writable, use ZERO_PAGE() */
+ page = ZERO_PAGE(address);
}
+out:
+ page_cache_get(page);
return page;
}
break;
}
- BUG_ON(!PageUptodate(page));
-
copied = filemap_copy_from_user(page, offset, buf, bytes);
flush_dcache_page(page);
if (likely(copied > 0)) {
return 0;
else
return PTR_ERR(page);
- } else
- BUG_ON(!PageUptodate(page));
+ }
kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr + offset, 0, length);
kunmap_atomic(kaddr, KM_USER0);