The patch titled
Subject: mm/filemap: restructure filemap_get_pages
has been added to the -mm tree. Its filename is
mm-filemap-restructure-filemap_get_pages.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-filemap-restructure-filemap_get_pages.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-filemap-restructure-filemap_get_pages.patch
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm/filemap: restructure filemap_get_pages
Remove the got_pages label, remove indentation, rename find_page to retry,
simplify error handling.
Link: https://lkml.kernel.org/r/20210122160140.223228-16-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/filemap.c | 71 +++++++++++++++++++------------------------------
1 file changed, 28 insertions(+), 43 deletions(-)
--- a/mm/filemap.c~mm-filemap-restructure-filemap_get_pages
+++ a/mm/filemap.c
@@ -2342,70 +2342,55 @@ static int filemap_get_pages(struct kioc
struct file_ra_state *ra = &filp->f_ra;
pgoff_t index = iocb->ki_pos >> PAGE_SHIFT;
pgoff_t last_index;
+ struct page *page;
int err = 0;
last_index = DIV_ROUND_UP(iocb->ki_pos + iter->count, PAGE_SIZE);
-find_page:
+retry:
if (fatal_signal_pending(current))
return -EINTR;
filemap_get_read_batch(mapping, index, last_index, pvec);
- if (pvec->nr)
- goto got_pages;
-
- if (iocb->ki_flags & IOCB_NOIO)
- return -EAGAIN;
-
- page_cache_sync_readahead(mapping, ra, filp, index, last_index - index);
-
- filemap_get_read_batch(mapping, index, last_index, pvec);
+ if (!pagevec_count(pvec)) {
+ if (iocb->ki_flags & IOCB_NOIO)
+ return -EAGAIN;
+ page_cache_sync_readahead(mapping, ra, filp, index,
+ last_index - index);
+ filemap_get_read_batch(mapping, index, last_index, pvec);
+ }
if (!pagevec_count(pvec)) {
if (iocb->ki_flags & (IOCB_NOWAIT | IOCB_WAITQ))
return -EAGAIN;
err = filemap_create_page(filp, mapping,
iocb->ki_pos >> PAGE_SHIFT, pvec);
if (err == AOP_TRUNCATED_PAGE)
- goto find_page;
+ goto retry;
return err;
}
-got_pages:
- {
- struct page *page = pvec->pages[pvec->nr - 1];
-
- if (PageReadahead(page)) {
- err = filemap_readahead(iocb, filp, mapping, page,
- last_index);
- if (err) {
- put_page(page);
- pvec->nr--;
- goto err;
- }
- }
- if (!PageUptodate(page)) {
- if ((iocb->ki_flags & IOCB_WAITQ) &&
- pagevec_count(pvec) > 1)
- iocb->ki_flags |= IOCB_NOWAIT;
- err = filemap_update_page(iocb, mapping, iter, page);
- if (err) {
- if (err < 0)
- put_page(page);
- pvec->nr--;
- }
- }
+ page = pvec->pages[pagevec_count(pvec) - 1];
+ if (PageReadahead(page)) {
+ err = filemap_readahead(iocb, filp, mapping, page, last_index);
+ if (err)
+ goto err;
+ }
+ if (!PageUptodate(page)) {
+ if ((iocb->ki_flags & IOCB_WAITQ) && pagevec_count(pvec) > 1)
+ iocb->ki_flags |= IOCB_NOWAIT;
+ err = filemap_update_page(iocb, mapping, iter, page);
+ if (err)
+ goto err;
}
+ return 0;
err:
- if (likely(pvec->nr))
+ if (err < 0)
+ put_page(page);
+ if (likely(--pvec->nr))
return 0;
if (err == AOP_TRUNCATED_PAGE)
- goto find_page;
- if (err)
- return err;
- /*
- * No pages and no error means we raced and should retry:
- */
- goto find_page;
+ goto retry;
+ return err;
}
/**
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-debug-improve-memcg-debugging.patch
mm-filemap-rename-generic_file_buffered_read-subfunctions.patch
mm-filemap-remove-dynamically-allocated-array-from-filemap_read.patch
mm-filemap-convert-filemap_get_pages-to-take-a-pagevec.patch
mm-filemap-use-head-pages-in-generic_file_buffered_read.patch
mm-filemap-pass-a-sleep-state-to-put_and_wait_on_page_locked.patch
mm-filemap-support-readpage-splitting-a-page.patch
mm-filemap-inline-__wait_on_page_locked_async-into-caller.patch
mm-filemap-dont-call-readpage-if-iocb_waitq-is-set.patch
mm-filemap-change-filemap_read_page-calling-conventions.patch
mm-filemap-change-filemap_create_page-calling-conventions.patch
mm-filemap-convert-filemap_update_page-to-return-an-errno.patch
mm-filemap-move-the-iocb-checks-into-filemap_update_page.patch
mm-filemap-add-filemap_range_uptodate.patch
mm-filemap-split-filemap_readahead-out-of-filemap_get_pages.patch
mm-filemap-restructure-filemap_get_pages.patch
mm-filemap-dont-relock-the-page-after-calling-readpage.patch
mm-make-pagecache-tagged-lookups-return-only-head-pages.patch
mm-shmem-use-pagevec_lookup-in-shmem_unlock_mapping.patch
mm-swap-optimise-get_shadow_from_swap_cache.patch
mm-add-fgp_entry.patch
mm-filemap-rename-find_get_entry-to-mapping_get_entry.patch
mm-filemap-add-helper-for-finding-pages.patch
mm-filemap-add-helper-for-finding-pages-fix.patch
mm-filemap-add-mapping_seek_hole_data.patch
mm-filemap-add-mapping_seek_hole_data-fix.patch
iomap-use-mapping_seek_hole_data.patch
mm-add-and-use-find_lock_entries.patch
mm-add-and-use-find_lock_entries-fix.patch
mm-add-an-end-parameter-to-find_get_entries.patch
mm-add-an-end-parameter-to-pagevec_lookup_entries.patch
mm-remove-nr_entries-parameter-from-pagevec_lookup_entries.patch
mm-pass-pvec-directly-to-find_get_entries.patch
mm-remove-pagevec_lookup_entries.patch
