[RFC 3/5] filemap: introduce filemap_invalidate_pages

Pavel Begunkov
2024-08-14T10:45:31Z

kiocb_invalidate_pages() is useful for the write path, however not
everything is backed by kiocb and we want to reuse the function for bio
based discard implementation. Extract and and reuse a new helper called
filemap_invalidate_pages(), which takes a argument indicating whether it
should be non-blocking and might return -EAGAIN.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/linux/pagemap.h | 2 ++
mm/filemap.c | 18 +++++++++++++-----
2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index d9c7edb6422b..e39c3a7ce33c 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -32,6 +32,8 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
pgoff_t start, pgoff_t end);
int kiocb_invalidate_pages(struct kiocb *iocb, size_t count);
void kiocb_invalidate_post_direct_write(struct kiocb *iocb, size_t count);
+int filemap_invalidate_pages(struct address_space *mapping,
+ loff_t pos, loff_t end, bool nowait);

int write_inode_now(struct inode *, int sync);
int filemap_fdatawrite(struct address_space *);
diff --git a/mm/filemap.c b/mm/filemap.c
index d62150418b91..74baec119239 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2712,14 +2712,12 @@ int kiocb_write_and_wait(struct kiocb *iocb, size_t count)
}
EXPORT_SYMBOL_GPL(kiocb_write_and_wait);

-int kiocb_invalidate_pages(struct kiocb *iocb, size_t count)
+int filemap_invalidate_pages(struct address_space *mapping,
+ loff_t pos, loff_t end, bool nowait)
{
- struct address_space *mapping = iocb->ki_filp->f_mapping;
- loff_t pos = iocb->ki_pos;
- loff_t end = pos + count - 1;
int ret;

- if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (nowait) {
/* we could block if there are any pages in the range */
if (filemap_range_has_page(mapping, pos, end))
return -EAGAIN;
@@ -2738,6 +2736,16 @@ int kiocb_invalidate_pages(struct kiocb *iocb, size_t count)
return invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT,
end >> PAGE_SHIFT);
}
+
+int kiocb_invalidate_pages(struct kiocb *iocb, size_t count)
+{
+ struct address_space *mapping = iocb->ki_filp->f_mapping;
+ loff_t pos = iocb->ki_pos;
+ loff_t end = pos + count - 1;
+
+ return filemap_invalidate_pages(mapping, pos, end,
+ iocb->ki_flags & IOCB_NOWAIT);
+}
EXPORT_SYMBOL_GPL(kiocb_invalidate_pages);

/**
--
2.45.2