From: Christoph Hellwig <hch@lst.de>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Kent Overstreet <kent.overstreet@gmail.com>,
Matthew Wilcox <willy@infradead.org>,
linux-mm@kvack.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH 04/13] mm: handle readahead in generic_file_buffered_read_pagenotuptodate
Date: Sat, 31 Oct 2020 09:59:55 +0100 [thread overview]
Message-ID: <20201031090004.452516-5-hch@lst.de> (raw)
In-Reply-To: <20201031090004.452516-1-hch@lst.de>
Move the calculation of the per-page variables and the readahead handling
from the only caller into generic_file_buffered_read_pagenotuptodate,
which now becomes a routine to handle everything related to bringing
one page uptodate and thus is renamed to filemap_read_one_page.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
mm/filemap.c | 63 +++++++++++++++++++++++-----------------------------
1 file changed, 28 insertions(+), 35 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index bae5b905aa7bdc..5cdf8090d4e12c 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2217,13 +2217,26 @@ static int filemap_readpage(struct kiocb *iocb, struct page *page)
return error;
}
-static int generic_file_buffered_read_pagenotuptodate(struct kiocb *iocb,
- struct iov_iter *iter, struct page *page, loff_t pos,
- loff_t count, bool first)
+static int filemap_make_page_uptodate(struct kiocb *iocb, struct iov_iter *iter,
+ struct page *page, pgoff_t pg_index, bool first)
{
- struct address_space *mapping = iocb->ki_filp->f_mapping;
+ struct file *file = iocb->ki_filp;
+ struct address_space *mapping = file->f_mapping;
+ loff_t last = iocb->ki_pos + iter->count;
+ pgoff_t last_index = (last + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ loff_t pos = max(iocb->ki_pos, (loff_t)pg_index << PAGE_SHIFT);
int error = -EAGAIN;
+ if (PageReadahead(page)) {
+ if (iocb->ki_flags & IOCB_NOIO)
+ goto put_page;
+ page_cache_async_readahead(mapping, &file->f_ra, file, page,
+ pg_index, last_index - pg_index);
+ }
+
+ if (PageUptodate(page))
+ return 0;
+
if (iocb->ki_flags & IOCB_NOWAIT)
goto put_page;
@@ -2255,8 +2268,8 @@ static int generic_file_buffered_read_pagenotuptodate(struct kiocb *iocb,
/* Did it get truncated before we got the lock? */
if (!page->mapping)
goto page_not_up_to_date_locked;
- if (!mapping->a_ops->is_partially_uptodate(page,
- pos & ~PAGE_MASK, count))
+ if (!mapping->a_ops->is_partially_uptodate(page, pos & ~PAGE_MASK,
+ last - pos))
goto page_not_up_to_date_locked;
unlock_page:
@@ -2360,35 +2373,15 @@ static int generic_file_buffered_read_get_pages(struct kiocb *iocb,
nr_got = 1;
got_pages:
for (i = 0; i < nr_got; i++) {
- struct page *page = pages[i];
- pgoff_t pg_index = index + i;
- loff_t pg_pos = max(iocb->ki_pos,
- (loff_t) pg_index << PAGE_SHIFT);
- loff_t pg_count = iocb->ki_pos + iter->count - pg_pos;
-
- if (PageReadahead(page)) {
- if (iocb->ki_flags & IOCB_NOIO) {
- for (j = i; j < nr_got; j++)
- put_page(pages[j]);
- nr_got = i;
- err = -EAGAIN;
- break;
- }
- page_cache_async_readahead(mapping, ra, filp, page,
- pg_index, last_index - pg_index);
- }
-
- if (!PageUptodate(page)) {
- err = generic_file_buffered_read_pagenotuptodate(iocb,
- iter, page, pg_pos, pg_count, i == 0);
- if (err) {
- if (err == AOP_TRUNCATED_PAGE)
- err = 0;
- for (j = i + 1; j < nr_got; j++)
- put_page(pages[j]);
- nr_got = i;
- break;
- }
+ err = filemap_make_page_uptodate(iocb, iter, pages[i],
+ index + i, i == 0);
+ if (err) {
+ if (err == AOP_TRUNCATED_PAGE)
+ err = 0;
+ for (j = i + 1; j < nr_got; j++)
+ put_page(pages[j]);
+ nr_got = i;
+ break;
}
}
--
2.28.0
next prev parent reply other threads:[~2020-10-31 9:11 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-31 8:59 clean up the generic pagecache read helpers Christoph Hellwig
2020-10-31 8:59 ` [PATCH 01/13] mm: simplify generic_file_buffered_read_readpage Christoph Hellwig
2020-10-31 8:59 ` [PATCH 02/13] mm: simplify generic_file_buffered_read_pagenotuptodate Christoph Hellwig
2020-10-31 8:59 ` [PATCH 03/13] mm: lift the nowait checks into generic_file_buffered_read_pagenotuptodate Christoph Hellwig
2020-10-31 8:59 ` Christoph Hellwig [this message]
2020-10-31 17:06 ` [PATCH 04/13] mm: handle readahead in generic_file_buffered_read_pagenotuptodate Matthew Wilcox
2020-11-01 10:31 ` Christoph Hellwig
2020-11-01 10:49 ` Matthew Wilcox
2020-11-01 10:51 ` Christoph Hellwig
2020-11-01 10:51 ` Christoph Hellwig
2020-11-01 11:04 ` Matthew Wilcox
2020-11-01 11:52 ` Christoph Hellwig
2020-11-01 14:55 ` Matthew Wilcox
2020-11-02 8:18 ` Christoph Hellwig
2020-10-31 8:59 ` [PATCH 05/13] mm: simplify generic_file_buffered_read_no_cached_page Christoph Hellwig
2020-10-31 16:20 ` Matthew Wilcox
2020-10-31 16:28 ` Matthew Wilcox
2020-11-01 10:29 ` Christoph Hellwig
2020-10-31 8:59 ` [PATCH 06/13] mm: factor out a filemap_find_get_pages helper Christoph Hellwig
2020-10-31 8:59 ` [PATCH 07/13] mm: refactor generic_file_buffered_read_get_pages Christoph Hellwig
2020-11-01 11:18 ` Matthew Wilcox
2020-10-31 8:59 ` [PATCH 08/13] mm: move putting the page on error out of filemap_readpage Christoph Hellwig
2020-10-31 9:00 ` [PATCH 09/13] mm: move putting the page on error out of filemap_make_page_uptodate Christoph Hellwig
2020-10-31 9:00 ` [PATCH 10/13] mm: open code readahead in filemap_new_page Christoph Hellwig
2020-11-01 11:20 ` Matthew Wilcox
2020-10-31 9:00 ` [PATCH 11/13] mm: streamline the partially uptodate checks in filemap_make_page_uptodate Christoph Hellwig
2020-11-01 11:23 ` Matthew Wilcox
2020-10-31 9:00 ` [PATCH 12/13] mm: rename generic_file_buffered_read to filemap_read Christoph Hellwig
2020-10-31 9:00 ` [PATCH 13/13] mm: simplify generic_file_read_iter Christoph Hellwig
2020-10-31 15:42 ` clean up the generic pagecache read helpers Matthew Wilcox
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=20201031090004.452516-5-hch@lst.de \
--to=hch@lst.de \
--cc=akpm@linux-foundation.org \
--cc=kent.overstreet@gmail.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--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).