@@ -2231,11 +2231,39 @@ static int filemap_read_page(struct file *file, struct address_space *mapping,
return error;
}
+static bool filemap_range_uptodate(struct kiocb *iocb,
+ struct address_space *mapping, struct iov_iter *iter,
+ struct page *page)
+{
+ loff_t pos;
+ int count;
+
+ if (PageUptodate(page))
+ return true;
+ /* pipes can't handle partially uptodate pages */
+ if (iov_iter_is_pipe(iter))
+ return false;
+ if (!mapping->a_ops->is_partially_uptodate)
+ return false;
+ if (mapping->host->i_blkbits >= (PAGE_SHIFT + thp_order(page)))
+ return false;
+
+ pos = (loff_t) page->index << PAGE_SHIFT;
+ if (pos > iocb->ki_pos) {
+ count = iocb->ki_pos + iter->count - pos;
+ pos = 0;
+ } else {
+ count = iter->count;
+ pos = iocb->ki_pos & (thp_size(page) - 1);
+ }
+
+ return mapping->a_ops->is_partially_uptodate(page, pos, count);
+}
+
static int filemap_update_page(struct kiocb *iocb,
struct address_space *mapping, struct iov_iter *iter,
- struct page *page, loff_t pos, loff_t count)
+ struct page *page)
{
- struct inode *inode = mapping->host;
int error = -EAGAIN;
if (!trylock_page(page)) {
@@ -2250,39 +2278,27 @@ static int filemap_update_page(struct kiocb *iocb,
goto error;
}
+ error = AOP_TRUNCATED_PAGE;
if (!page->mapping)
- goto truncated;
- if (PageUptodate(page))
- goto uptodate;
- if (inode->i_blkbits == PAGE_SHIFT ||
- !mapping->a_ops->is_partially_uptodate)
- goto readpage;
- /* pipes can't handle partially uptodate pages */
- if (unlikely(iov_iter_is_pipe(iter)))
- goto readpage;
- if (!mapping->a_ops->is_partially_uptodate(page,
- pos & (thp_size(page) - 1), count))
- goto readpage;
-uptodate:
- unlock_page(page);
- return 0;
-
-readpage:
- if (iocb->ki_flags & (IOCB_NOIO | IOCB_NOWAIT | IOCB_WAITQ)) {
+ goto unlock;
+ if (filemap_range_uptodate(iocb, mapping, iter, page)) {
unlock_page(page);
- error = -EAGAIN;
- } else {
- error = filemap_read_page(iocb->ki_filp, mapping, page);
- if (!error)
- return 0;
+ return 0;
}
+
+ error = -EAGAIN;
+ if (iocb->ki_flags & (IOCB_NOIO | IOCB_NOWAIT | IOCB_WAITQ))
+ goto unlock;
+
+ error = filemap_read_page(iocb->ki_filp, mapping, page);
+ if (error)
+ goto error;
+ return 0;
+unlock:
+ unlock_page(page);
error:
put_page(page);
return error;
-truncated:
- unlock_page(page);
- put_page(page);
- return AOP_TRUNCATED_PAGE;
}
static int filemap_create_page(struct file *file,
@@ -2353,9 +2369,6 @@ static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,
{
struct page *page = pvec->pages[pvec->nr - 1];
pgoff_t pg_index = page->index;
- loff_t pg_pos = max(iocb->ki_pos,
- (loff_t) pg_index << PAGE_SHIFT);
- loff_t pg_count = iocb->ki_pos + iter->count - pg_pos;
if (PageReadahead(page)) {
if (iocb->ki_flags & IOCB_NOIO) {
@@ -2372,8 +2385,7 @@ static int filemap_get_pages(struct kiocb *iocb, struct iov_iter *iter,
if ((iocb->ki_flags & IOCB_WAITQ) &&
pagevec_count(pvec) > 1)
iocb->ki_flags |= IOCB_NOWAIT;
- err = filemap_update_page(iocb, mapping, iter, page,
- pg_pos, pg_count);
+ err = filemap_update_page(iocb, mapping, iter, page);
if (err)
pvec->nr--;
}