From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
To: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>,
"Darrick J . Wong" <darrick.wong@oracle.com>,
linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org
Subject: [PATCH 5/9] iomap: Support arbitrarily many blocks per page
Date: Mon, 24 Aug 2020 15:55:06 +0100 [thread overview]
Message-ID: <20200824145511.10500-6-willy@infradead.org> (raw)
In-Reply-To: <20200824145511.10500-1-willy@infradead.org>
Size the uptodate array dynamically to support larger pages in the
page cache. With a 64kB page, we're only saving 8 bytes per page today,
but with a 2MB maximum page size, we'd have to allocate more than 4kB
per page. Add a few debugging assertions.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
fs/iomap/buffered-io.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index dbf9572dabe9..844e95cacea8 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -22,18 +22,19 @@
#include "../internal.h"
/*
- * Structure allocated for each page when block size < PAGE_SIZE to track
+ * Structure allocated for each page when block size < page size to track
* sub-page uptodate status and I/O completions.
*/
struct iomap_page {
atomic_t read_count;
atomic_t write_count;
spinlock_t uptodate_lock;
- DECLARE_BITMAP(uptodate, PAGE_SIZE / 512);
+ unsigned long uptodate[];
};
static inline struct iomap_page *to_iomap_page(struct page *page)
{
+ VM_BUG_ON_PGFLAGS(PageTail(page), page);
if (page_has_private(page))
return (struct iomap_page *)page_private(page);
return NULL;
@@ -45,11 +46,13 @@ static struct iomap_page *
iomap_page_create(struct inode *inode, struct page *page)
{
struct iomap_page *iop = to_iomap_page(page);
+ unsigned int nr_blocks = i_blocks_per_page(inode, page);
- if (iop || i_blocks_per_page(inode, page) <= 1)
+ if (iop || nr_blocks <= 1)
return iop;
- iop = kzalloc(sizeof(*iop), GFP_NOFS | __GFP_NOFAIL);
+ iop = kzalloc(struct_size(iop, uptodate, BITS_TO_LONGS(nr_blocks)),
+ GFP_NOFS | __GFP_NOFAIL);
spin_lock_init(&iop->uptodate_lock);
attach_page_private(page, iop);
return iop;
@@ -59,11 +62,14 @@ static void
iomap_page_release(struct page *page)
{
struct iomap_page *iop = detach_page_private(page);
+ unsigned int nr_blocks = i_blocks_per_page(page->mapping->host, page);
if (!iop)
return;
WARN_ON_ONCE(atomic_read(&iop->read_count));
WARN_ON_ONCE(atomic_read(&iop->write_count));
+ WARN_ON_ONCE(bitmap_full(iop->uptodate, nr_blocks) !=
+ PageUptodate(page));
kfree(iop);
}
--
2.28.0
next prev parent reply other threads:[~2020-08-24 15:11 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-24 14:55 [PATCH 0/9] THP iomap patches for 5.10 Matthew Wilcox (Oracle)
2020-08-24 14:55 ` [PATCH 1/9] iomap: Fix misplaced page flushing Matthew Wilcox (Oracle)
2020-08-24 23:51 ` Dave Chinner
2020-08-25 20:47 ` Darrick J. Wong
2020-08-27 8:24 ` Christoph Hellwig
2020-08-24 14:55 ` [PATCH 2/9] fs: Introduce i_blocks_per_page Matthew Wilcox (Oracle)
2020-08-24 23:55 ` Dave Chinner
2020-08-25 20:49 ` Darrick J. Wong
2020-08-25 22:21 ` Dave Chinner
2020-08-24 14:55 ` [PATCH 3/9] iomap: Use kzalloc to allocate iomap_page Matthew Wilcox (Oracle)
2020-08-24 23:56 ` Dave Chinner
2020-08-25 20:49 ` Darrick J. Wong
2020-08-24 14:55 ` [PATCH 4/9] iomap: Use bitmap ops to set uptodate bits Matthew Wilcox (Oracle)
2020-08-24 23:56 ` Dave Chinner
2020-08-25 20:50 ` Darrick J. Wong
2020-08-24 14:55 ` Matthew Wilcox (Oracle) [this message]
2020-08-24 23:59 ` [PATCH 5/9] iomap: Support arbitrarily many blocks per page Dave Chinner
2020-08-25 0:22 ` Matthew Wilcox
2020-08-25 21:02 ` Darrick J. Wong
2020-08-26 2:26 ` Matthew Wilcox
2020-08-26 3:32 ` Darrick J. Wong
2020-08-27 8:26 ` Christoph Hellwig
2020-08-24 14:55 ` [PATCH 6/9] iomap: Convert read_count to byte count Matthew Wilcox (Oracle)
2020-08-25 0:09 ` Dave Chinner
2020-08-25 22:14 ` Darrick J. Wong
2020-08-27 8:35 ` Christoph Hellwig
2020-08-24 14:55 ` [PATCH 7/9] iomap: Convert write_count " Matthew Wilcox (Oracle)
2020-08-27 8:36 ` Christoph Hellwig
2020-08-24 14:55 ` [PATCH 8/9] iomap: Convert iomap_write_end types Matthew Wilcox (Oracle)
2020-08-25 0:12 ` Dave Chinner
2020-08-25 1:06 ` Matthew Wilcox
2020-08-25 1:33 ` Dave Chinner
2020-08-27 8:41 ` Christoph Hellwig
2020-08-24 14:55 ` [PATCH 9/9] iomap: Change calling convention for zeroing Matthew Wilcox (Oracle)
2020-08-25 0:27 ` Dave Chinner
2020-08-25 3:26 ` Matthew Wilcox
2020-08-25 3:35 ` Andreas Dilger
2020-08-25 4:27 ` Dave Chinner
2020-08-25 12:40 ` Matthew Wilcox
2020-08-25 22:05 ` Dave Chinner
2020-08-25 22:23 ` Darrick J. Wong
2020-08-27 8:39 ` Christoph Hellwig
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=20200824145511.10500-6-willy@infradead.org \
--to=willy@infradead.org \
--cc=darrick.wong@oracle.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvdimm@lists.01.org \
--cc=linux-xfs@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).