From: Qu Wenruo <wqu@suse.com>
To: linux-btrfs@vger.kernel.org
Cc: Josef Bacik <josef@toxicpanda.com>
Subject: [PATCH v3 07/22] btrfs: extent_io: introduce the skeleton of btrfs_subpage structure
Date: Wed, 6 Jan 2021 09:01:46 +0800 [thread overview]
Message-ID: <20210106010201.37864-8-wqu@suse.com> (raw)
In-Reply-To: <20210106010201.37864-1-wqu@suse.com>
For btrfs subpage support, we need a structure to record extra info for
the status of each sectors of a page.
This patch will introduce the skeleton structure for future btrfs
subpage support.
All subpage related code would go to subpage.[ch] to avoid populating
the existing code base.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
---
fs/btrfs/Makefile | 3 ++-
fs/btrfs/subpage.c | 39 +++++++++++++++++++++++++++++++++++++++
fs/btrfs/subpage.h | 31 +++++++++++++++++++++++++++++++
3 files changed, 72 insertions(+), 1 deletion(-)
create mode 100644 fs/btrfs/subpage.c
create mode 100644 fs/btrfs/subpage.h
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index 9f1b1a88e317..942562e11456 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -11,7 +11,8 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \
reada.o backref.o ulist.o qgroup.o send.o dev-replace.o raid56.o \
uuid-tree.o props.o free-space-tree.o tree-checker.o space-info.o \
- block-rsv.o delalloc-space.o block-group.o discard.o reflink.o
+ block-rsv.o delalloc-space.o block-group.o discard.o reflink.o \
+ subpage.o
btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o
diff --git a/fs/btrfs/subpage.c b/fs/btrfs/subpage.c
new file mode 100644
index 000000000000..c6ab32db3995
--- /dev/null
+++ b/fs/btrfs/subpage.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "subpage.h"
+
+int btrfs_attach_subpage(struct btrfs_fs_info *fs_info, struct page *page)
+{
+ struct btrfs_subpage *subpage;
+
+ /*
+ * We have cases like a dummy extent buffer page, which is not
+ * mappped and doesn't need to be locked.
+ */
+ if (page->mapping)
+ ASSERT(PageLocked(page));
+ /* Either not subpage, or the page already has private attached */
+ if (fs_info->sectorsize == PAGE_SIZE || PagePrivate(page))
+ return 0;
+
+ subpage = kzalloc(sizeof(*subpage), GFP_NOFS);
+ if (!subpage)
+ return -ENOMEM;
+
+ spin_lock_init(&subpage->lock);
+ attach_page_private(page, subpage);
+ return 0;
+}
+
+void btrfs_detach_subpage(struct btrfs_fs_info *fs_info, struct page *page)
+{
+ struct btrfs_subpage *subpage;
+
+ /* Either not subpage, or already detached */
+ if (fs_info->sectorsize == PAGE_SIZE || !PagePrivate(page))
+ return;
+
+ subpage = (struct btrfs_subpage *)detach_page_private(page);
+ ASSERT(subpage);
+ kfree(subpage);
+}
diff --git a/fs/btrfs/subpage.h b/fs/btrfs/subpage.h
new file mode 100644
index 000000000000..96f3b226913e
--- /dev/null
+++ b/fs/btrfs/subpage.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_SUBPAGE_H
+#define BTRFS_SUBPAGE_H
+
+#include <linux/spinlock.h>
+#include "ctree.h"
+
+/*
+ * Since the maximum page size btrfs is going to support is 64K while the
+ * minimum sectorsize is 4K, this means a u16 bitmap is enough.
+ *
+ * The regular bitmap requires 32 bits as minimal bitmap size, so we can't use
+ * existing bitmap_* helpers here.
+ */
+#define BTRFS_SUBPAGE_BITMAP_SIZE 16
+
+/*
+ * Structure to trace status of each sector inside a page.
+ *
+ * Will be attached to page::private for both data and metadata inodes.
+ */
+struct btrfs_subpage {
+ /* Common members for both data and metadata pages */
+ spinlock_t lock;
+};
+
+int btrfs_attach_subpage(struct btrfs_fs_info *fs_info, struct page *page);
+void btrfs_detach_subpage(struct btrfs_fs_info *fs_info, struct page *page);
+
+#endif /* BTRFS_SUBPAGE_H */
--
2.29.2
next prev parent reply other threads:[~2021-01-06 1:03 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-06 1:01 [PATCH v3 00/22] btrfs: add read-only support for subpage sector size Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 01/22] btrfs: extent_io: rename @offset parameter to @disk_bytenr for submit_extent_page() Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 02/22] btrfs: extent_io: refactor __extent_writepage_io() to improve readability Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 03/22] btrfs: file: update comment for btrfs_dirty_pages() Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 04/22] btrfs: extent_io: update locked page dirty/writeback/error bits in __process_pages_contig() Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 05/22] btrfs: extent_io: merge PAGE_CLEAR_DIRTY and PAGE_SET_WRITEBACK into PAGE_START_WRITEBACK Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 06/22] btrfs: extent_io: introduce a helper to grab an existing extent buffer from a page Qu Wenruo
2021-01-12 15:08 ` David Sterba
2021-01-06 1:01 ` Qu Wenruo [this message]
2021-01-06 1:01 ` [PATCH v3 08/22] btrfs: extent_io: make attach_extent_buffer_page() to handle subpage case Qu Wenruo
2021-01-06 6:54 ` Qu Wenruo
2021-01-07 1:35 ` Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 09/22] btrfs: extent_io: make grab_extent_buffer_from_page() " Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 10/22] btrfs: extent_io: support subpage for extent buffer page release Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 11/22] btrfs: extent_io: attach private to dummy extent buffer pages Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 12/22] btrfs: subpage: introduce helper for subpage uptodate status Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 13/22] btrfs: subpage: introduce helper for subpage error status Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 14/22] btrfs: extent_io: make set/clear_extent_buffer_uptodate() to support subpage size Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 15/22] btrfs: extent_io: make btrfs_clone_extent_buffer() to be subpage compatible Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 16/22] btrfs: extent_io: implement try_release_extent_buffer() for subpage metadata support Qu Wenruo
2021-01-06 8:24 ` Qu Wenruo
2021-01-06 8:43 ` Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 17/22] btrfs: extent_io: introduce read_extent_buffer_subpage() Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 18/22] btrfs: extent_io: make endio_readpage_update_page_status() to handle subpage case Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 19/22] btrfs: disk-io: introduce subpage metadata validation check Qu Wenruo
2021-01-06 1:01 ` [PATCH v3 20/22] btrfs: introduce btrfs_subpage for data inodes Qu Wenruo
2021-01-06 5:04 ` kernel test robot
2021-01-06 5:32 ` Qu Wenruo
2021-01-06 6:48 ` Rong Chen
2021-01-09 9:53 ` kernel test robot
2021-01-06 1:02 ` [PATCH v3 21/22] btrfs: integrate page status update for read path into begin/end_page_read() Qu Wenruo
2021-01-06 1:02 ` [PATCH v3 22/22] btrfs: allow RO mount of 4K sector size fs on 64K page system Qu Wenruo
2021-01-12 15:14 ` [PATCH v3 00/22] btrfs: add read-only support for subpage sector size David Sterba
2021-01-13 5:06 ` Qu Wenruo
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=20210106010201.37864-8-wqu@suse.com \
--to=wqu@suse.com \
--cc=josef@toxicpanda.com \
--cc=linux-btrfs@vger.kernel.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).