[PATCH v3 12/25] iomap: Convert iomap_read_inline_data to take a folio

From: Matthew Wilcox (Oracle)
Date: Thu Dec 16 2021 - 16:08:21 EST


We still only support up to a single page of inline data (at least,
per call to iomap_read_inline_data()), but it can now be written into
the middle of a folio in case we decide to allocate a 16KiB page for
a file that's 8.1KiB in size.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
---
fs/iomap/buffered-io.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 06ff80c05340..2ebea02780b8 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -197,16 +197,15 @@ struct iomap_readpage_ctx {
/**
* iomap_read_inline_data - copy inline data into the page cache
* @iter: iteration structure
- * @page: page to copy to
+ * @folio: folio to copy to
*
- * Copy the inline data in @iter into @page and zero out the rest of the page.
+ * Copy the inline data in @iter into @folio and zero out the rest of the folio.
* Only a single IOMAP_INLINE extent is allowed at the end of each file.
* Returns zero for success to complete the read, or the usual negative errno.
*/
static int iomap_read_inline_data(const struct iomap_iter *iter,
- struct page *page)
+ struct folio *folio)
{
- struct folio *folio = page_folio(page);
struct iomap_page *iop;
const struct iomap *iomap = iomap_iter_srcmap(iter);
size_t size = i_size_read(iter->inode) - iomap->offset;
@@ -214,7 +213,7 @@ static int iomap_read_inline_data(const struct iomap_iter *iter,
size_t offset = offset_in_folio(folio, iomap->offset);
void *addr;

- if (PageUptodate(page))
+ if (folio_test_uptodate(folio))
return 0;

if (WARN_ON_ONCE(size > PAGE_SIZE - poff))
@@ -229,7 +228,7 @@ static int iomap_read_inline_data(const struct iomap_iter *iter,
else
iop = to_iomap_page(folio);

- addr = kmap_local_page(page) + poff;
+ addr = kmap_local_folio(folio, offset);
memcpy(addr, iomap->inline_data, size);
memset(addr + size, 0, PAGE_SIZE - poff - size);
kunmap_local(addr);
@@ -261,7 +260,7 @@ static loff_t iomap_readpage_iter(const struct iomap_iter *iter,
sector_t sector;

if (iomap->type == IOMAP_INLINE)
- return iomap_read_inline_data(iter, page);
+ return iomap_read_inline_data(iter, folio);

/* zero post-eof blocks as the page may be mapped */
iop = iomap_page_create(iter->inode, folio);
@@ -597,10 +596,12 @@ static int __iomap_write_begin(const struct iomap_iter *iter, loff_t pos,
static int iomap_write_begin_inline(const struct iomap_iter *iter,
struct page *page)
{
+ struct folio *folio = page_folio(page);
+
/* needs more work for the tailpacking case; disable for now */
if (WARN_ON_ONCE(iomap_iter_srcmap(iter)->offset != 0))
return -EIO;
- return iomap_read_inline_data(iter, page);
+ return iomap_read_inline_data(iter, folio);
}

static int iomap_write_begin(const struct iomap_iter *iter, loff_t pos,
--
2.33.0