From: David Howells <dhowells@redhat.com>
To: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: dhowells@redhat.com, Jeff Layton <jlayton@kernel.org>,
Ilya Dryomov <idryomov@gmail.com>,
linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com,
linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org,
linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org,
v9fs-developer@lists.sourceforge.net, devel@lists.orangefs.org,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: [PATCH v2 4/6] folio: Add a function to get the host inode for a folio
Date: Fri, 27 Aug 2021 10:44:03 +0100 [thread overview]
Message-ID: <163005744370.2472992.18324470937328925723.stgit@warthog.procyon.org.uk> (raw)
In-Reply-To: <163005740700.2472992.12365214290752300378.stgit@warthog.procyon.org.uk>
Add a convenience function, folio_inode() that will get the host inode from
a folio's mapping.
Changes:
ver #2:
- Fix contradiction between doc and implementation by disallowing use
with swap caches[1].
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/YST8OcVNy02Rivbm@casper.infradead.org/ [1]
Link: https://lore.kernel.org/r/162880453171.3369675.3704943108660112470.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/162981151155.1901565.7010079316994382707.stgit@warthog.procyon.org.uk/
---
include/linux/pagemap.h | 14 ++++++++++++++
mm/page-writeback.c | 2 +-
2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index c8d336e62177..320f1f4db1a5 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -203,6 +203,20 @@ static inline struct address_space *page_mapping_file(struct page *page)
return folio_mapping(folio);
}
+/**
+ * folio_inode - Get the host inode for this folio.
+ * @folio: The folio.
+ *
+ * For folios which are in the page cache, return the inode that is hosting
+ * this folio belongs to.
+ *
+ * Do not call this for folios which aren't in the page cache.
+ */
+static inline struct inode *folio_inode(struct folio *folio)
+{
+ return folio->mapping->host;
+}
+
static inline bool page_cache_add_speculative(struct page *page, int count)
{
VM_BUG_ON_PAGE(PageTail(page), page);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 86b90173baf8..f750946d11f7 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2918,7 +2918,7 @@ EXPORT_SYMBOL_GPL(folio_wait_writeback_killable);
*/
void folio_wait_stable(struct folio *folio)
{
- if (folio->mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES)
+ if (folio_inode(folio)->i_sb->s_iflags & SB_I_STABLE_WRITES)
folio_wait_writeback(folio);
}
EXPORT_SYMBOL_GPL(folio_wait_stable);
next prev parent reply other threads:[~2021-08-27 9:46 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-27 9:43 [PATCH v2 0/6] netfs, afs, ceph: Support folios, at least partially David Howells
2021-08-27 9:43 ` [PATCH v2 1/6] afs: Fix afs_launder_page() to set correct start file position David Howells
2021-08-27 9:43 ` [PATCH v2 2/6] afs: Sort out symlink reading David Howells
2021-08-27 9:43 ` [PATCH v2 3/6] folio: Add a function to change the private data attached to a folio David Howells
2021-08-27 9:44 ` David Howells [this message]
2021-08-27 9:44 ` [PATCH v2 5/6] netfs, afs, ceph: Use folios David Howells
2021-09-08 19:06 ` Jeff Layton
2021-08-27 9:44 ` [PATCH v2 6/6] afs: Use folios in directory handling David Howells
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=163005744370.2472992.18324470937328925723.stgit@warthog.procyon.org.uk \
--to=dhowells@redhat.com \
--cc=ceph-devel@vger.kernel.org \
--cc=devel@lists.orangefs.org \
--cc=idryomov@gmail.com \
--cc=jlayton@kernel.org \
--cc=linux-afs@lists.infradead.org \
--cc=linux-cachefs@redhat.com \
--cc=linux-cifs@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-nfs@vger.kernel.org \
--cc=v9fs-developer@lists.sourceforge.net \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).