[PATCH 2/2] ceph: split out page-array discarding to a function

Sam Edwards
2026-01-26T02:27:50Z

Discarding a page array (i.e. after failure to submit it) is a little
complex:
- Every folio in the batch needs to be redirtied and unlocked.
- Some folios are bounce pages created for fscrypt; the underlying
plaintext folios also need to be redirtied and unlocked.
- The array itself can come either from the mempool or general kalloc,
so different free functions need to be used depending on which.

Although currently only ceph_submit_write() does this, this logic is
complex enough to warrant its own function. Move it to a new
ceph_discard_page_array() function that is called by ceph_submit_write()
instead.

Suggested-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Reviewed-by: Viacheslav Dubeyko <Slava.Dubeyko@ibm.com>
Signed-off-by: Sam Edwards <CFSworks@gmail.com>
---
fs/ceph/addr.c | 67 ++++++++++++++++++++++++++++----------------------
1 file changed, 38 insertions(+), 29 deletions(-)

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index c3e0b5b429ea..28463b9a3bae 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1222,6 +1222,43 @@ void ceph_allocate_page_array(struct address_space *mapping,
ceph_wbc->len = 0;
}

+static inline
+void ceph_discard_page_array(struct writeback_control *wbc,
+ struct ceph_writeback_ctl *ceph_wbc)
+{
+ int i;
+ struct page *page;
+
+ for (i = 0; i < folio_batch_count(&ceph_wbc->fbatch); i++) {
+ struct folio *folio = ceph_wbc->fbatch.folios[i];
+
+ if (!folio)
+ continue;
+
+ page = &folio->page;
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ }
+
+ for (i = 0; i < ceph_wbc->locked_pages; i++) {
+ page = ceph_fscrypt_pagecache_page(ceph_wbc->pages[i]);
+
+ if (!page)
+ continue;
+
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ }
+
+ if (ceph_wbc->from_pool) {
+ mempool_free(ceph_wbc->pages, ceph_wb_pagevec_pool);
+ ceph_wbc->from_pool = false;
+ } else
+ kfree(ceph_wbc->pages);
+ ceph_wbc->pages = NULL;
+ ceph_wbc->locked_pages = 0;
+}
+
static inline
bool is_folio_index_contiguous(const struct ceph_writeback_ctl *ceph_wbc,
const struct folio *folio)
@@ -1449,35 +1486,7 @@ int ceph_submit_write(struct address_space *mapping,
BUG_ON(len < ceph_fscrypt_page_offset(page) + thp_size(page) - offset);

if (!ceph_inc_osd_stopping_blocker(fsc->mdsc)) {
- for (i = 0; i < folio_batch_count(&ceph_wbc->fbatch); i++) {
- struct folio *folio = ceph_wbc->fbatch.folios[i];
-
- if (!folio)
- continue;
-
- page = &folio->page;
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- }
-
- for (i = 0; i < ceph_wbc->locked_pages; i++) {
- page = ceph_fscrypt_pagecache_page(ceph_wbc->pages[i]);
-
- if (!page)
- continue;
-
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- }
-
- if (ceph_wbc->from_pool) {
- mempool_free(ceph_wbc->pages, ceph_wb_pagevec_pool);
- ceph_wbc->from_pool = false;
- } else
- kfree(ceph_wbc->pages);
- ceph_wbc->pages = NULL;
- ceph_wbc->locked_pages = 0;
-
+ ceph_discard_page_array(wbc, ceph_wbc);
ceph_osdc_put_request(req);
return -EIO;
}
--
2.52.0