File 98da34a.diff of Package openafs
From 98da34a2718220adea97f9169c053d706f9481e3 Mon Sep 17 00:00:00 2001
From: Cheyenne Wills <cwills@sinenomine.net>
Date: Tue, 27 May 2025 13:46:54 -0600
Subject: [PATCH] Linux: Use __filemap_get_folio()
The Linux 6.15 commit:
mm: Remove grab_cache_page_write_begin() (e33ce6bd4ea2)
removed grab_cache_page_write_begin() which had been a wrapper for
__filemap_get_folio(). The functions __filemap_get_folio() and
filemap_get_folio() were introduced in the Linux 5.16 commit:
mm/filemap: Add filemap_get_folio (3f0c6a07fee6)
Add a new configure test for __filemap_get_folio().
The function afs_linux_write_begin() can only use __filemap_get_folio
after the Linux 6.12 commit:
fs: Convert aops->write_begin to take a folio (1da86618bdce3)
(HAVE_LINUX_WRITE_BEGIN_END_FOLIO)
Replace the call to grab_cache_page_write_begin() with
__filemap_get_folio() and use folio_unlock()/folio_put() to release the
folio.
Note: The function grab_cache_page_write_begin() was introduced in
Linux 2.6.29 where it renamed __grab_cache_page() and added additional
parameters. It was added in the Linux 2.6.29 commit:
fs: symlink write_begin allocation context fix (54566b2c1594)
To handle kernels older than 2.6.29, OpenAFS has had its own version of
grab_cache_page_write_begin() that simply front-ended
__grab_cache_page().
Add an additional preprocessor check to not build with the openafs
version of grab_cache_page_write_begin if __filemap_get_folio() is
available.
NOTE: To summarize the timeline of when Linux features where added or
changed:
Linux 2.6.9 added the grab_cache_page_write_begin
Linux 5.16 added the __filemap_get_folio as a replacement for
grab_cache_page_write_begin for use with folios
Linux 6.12 converted aops->write_begin to use a folio
Linux 6.15 removed grab_cache_page_write_begin
Reviewed-on: https://gerrit.openafs.org/16374
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Cheyenne Wills <cwills@sinenomine.net>
Reviewed-by: Mark Vitale <mvitale@sinenomine.net>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
(cherry picked from commit f1b8ca0d664f018a6393e54133413ec4fe9f4e28)
Change-Id: I992de9b4ac77ab502ba6da2ee902b2540bbad0bb
---
diff --git a/src/afs/LINUX/osi_compat.h b/src/afs/LINUX/osi_compat.h
index 59ad337..0fc72a3 100644
--- a/src/afs/LINUX/osi_compat.h
+++ b/src/afs/LINUX/osi_compat.h
@@ -161,7 +161,8 @@
#if defined(STRUCT_ADDRESS_SPACE_OPERATIONS_HAS_WRITE_BEGIN) && \
!defined(HAVE_LINUX_GRAB_CACHE_PAGE_WRITE_BEGIN_WITHFLAGS) && \
- !defined(HAVE_LINUX_GRAB_CACHE_PAGE_WRITE_BEGIN_NOFLAGS)
+ !defined(HAVE_LINUX_GRAB_CACHE_PAGE_WRITE_BEGIN_NOFLAGS) && \
+ !defined(HAVE_LINUX_FILEMAP_GET_FOLIO)
static inline struct page *
grab_cache_page_write_begin(struct address_space *mapping, pgoff_t index,
unsigned int flags) {
diff --git a/src/afs/LINUX/osi_vnodeops.c b/src/afs/LINUX/osi_vnodeops.c
index ffa795c..9ae1211 100644
--- a/src/afs/LINUX/osi_vnodeops.c
+++ b/src/afs/LINUX/osi_vnodeops.c
@@ -3637,6 +3637,31 @@
return code;
}
+# if defined(HAVE_LINUX_FILEMAP_GET_FOLIO)
+static int
+afs_linux_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len,
+ struct folio **foliop, void **fsdata)
+{
+ struct page *page;
+ pgoff_t index = pos >> PAGE_SHIFT;
+ unsigned int from = pos & (PAGE_SIZE - 1);
+ int code;
+
+ *foliop = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN, mapping_gfp_mask(mapping));
+ if (IS_ERR(*foliop)) {
+ return PTR_ERR(*foliop);
+ }
+ page = folio_page(*foliop, 0);
+ code = afs_linux_prepare_write(file, page, from, from + len);
+ if (code != 0) {
+ folio_unlock(*foliop);
+ folio_put(*foliop);
+ *foliop = NULL;
+ }
+ return code;
+}
+# else /* HAVE_LINUX_FILEMAP_GET_FOLIO */
static int
afs_linux_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len,
@@ -3665,6 +3690,7 @@
return code;
}
+# endif /* HAVE_LINUX_FILEMAP_GET_FOLIO */
#elif defined(STRUCT_ADDRESS_SPACE_OPERATIONS_HAS_WRITE_BEGIN)
diff --git a/src/cf/linux-kernel-func.m4 b/src/cf/linux-kernel-func.m4
index 9a0d41a..679375d 100644
--- a/src/cf/linux-kernel-func.m4
+++ b/src/cf/linux-kernel-func.m4
@@ -336,6 +336,14 @@
#include <linux/fs.h>]],
[[folio_wait_locked(NULL);]])
+dnl Linux 5.16 added __filemap_get_folio to replace grab_cache_page_write_begin
+dnl Linux 6.15 removed grab_cache_page_write_begin
+AC_CHECK_LINUX_FUNC([filemap_get_folio],
+ [[#include <linux/pagemap.h>
+ #include <linux/fs.h>
+ static struct folio *folio;]],
+ [[folio = __filemap_get_folio(NULL, 0, 0, 0);]])
+
dnl Consequences - things which get set as a result of the
dnl above tests
AS_IF([test "x$ac_cv_linux_func_d_alloc_anon" = "xno"],
