[PATCH v13 100/137] iomap: Convert iomap_page_mkwrite to use a folio

From: Matthew Wilcox (Oracle)
Date: Mon Jul 12 2021 - 00:00:27 EST


If we write to any page in a folio, we have to mark the entire
folio as dirty, and potentially COW the entire folio, because it'll
all get written back as one unit.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
fs/iomap/buffered-io.c | 42 +++++++++++++++++++++---------------------
1 file changed, 21 insertions(+), 21 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index bdce467ed5d3..2ecfebdd1f4f 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -951,23 +951,23 @@ iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
}
EXPORT_SYMBOL_GPL(iomap_truncate_page);

-static loff_t
-iomap_page_mkwrite_actor(struct inode *inode, loff_t pos, loff_t length,
- void *data, struct iomap *iomap, struct iomap *srcmap)
+static loff_t iomap_folio_mkwrite_actor(struct inode *inode, loff_t pos,
+ loff_t length, void *data, struct iomap *iomap,
+ struct iomap *srcmap)
{
- struct page *page = data;
- struct folio *folio = page_folio(page);
+ struct folio *folio = data;
int ret;

if (iomap->flags & IOMAP_F_BUFFER_HEAD) {
- ret = __block_write_begin_int(page, pos, length, NULL, iomap);
+ ret = __block_write_begin_int(&folio->page, pos, length, NULL,
+ iomap);
if (ret)
return ret;
- block_commit_write(page, 0, length);
+ block_commit_write(&folio->page, 0, length);
} else {
- WARN_ON_ONCE(!PageUptodate(page));
+ WARN_ON_ONCE(!folio_uptodate(folio));
iomap_page_create(inode, folio);
- set_page_dirty(page);
+ folio_mark_dirty(folio);
}

return length;
@@ -975,33 +975,33 @@ iomap_page_mkwrite_actor(struct inode *inode, loff_t pos, loff_t length,

vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops)
{
- struct page *page = vmf->page;
+ struct folio *folio = page_folio(vmf->page);
struct inode *inode = file_inode(vmf->vma->vm_file);
- unsigned long length;
- loff_t offset;
+ size_t length;
+ loff_t pos;
ssize_t ret;

- lock_page(page);
- ret = page_mkwrite_check_truncate(page, inode);
+ folio_lock(folio);
+ ret = folio_mkwrite_check_truncate(folio, inode);
if (ret < 0)
goto out_unlock;
length = ret;

- offset = page_offset(page);
+ pos = folio_pos(folio);
while (length > 0) {
- ret = iomap_apply(inode, offset, length,
- IOMAP_WRITE | IOMAP_FAULT, ops, page,
- iomap_page_mkwrite_actor);
+ ret = iomap_apply(inode, pos, length,
+ IOMAP_WRITE | IOMAP_FAULT, ops, folio,
+ iomap_folio_mkwrite_actor);
if (unlikely(ret <= 0))
goto out_unlock;
- offset += ret;
+ pos += ret;
length -= ret;
}

- wait_for_stable_page(page);
+ folio_wait_stable(folio);
return VM_FAULT_LOCKED;
out_unlock:
- unlock_page(page);
+ folio_unlock(folio);
return block_page_mkwrite_return(ret);
}
EXPORT_SYMBOL_GPL(iomap_page_mkwrite);
--
2.30.2