The patch titled
Subject: filemap: fix page_cache_next_miss() when no hole found
has been added to the -mm mm-unstable branch. Its filename is
filemap-fix-page_cache_next_miss-when-no-hole-found.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/filemap-fix-page_cache_next_miss-when-no-hole-found.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Jan Kara <jack@xxxxxxx>
Subject: filemap: fix page_cache_next_miss() when no hole found
Date: Tue, 25 Jun 2024 12:18:52 +0200
page_cache_next_miss() should return value outside of the specified range
when no hole is found. However currently it will return the last index
*in* the specified range confusing ondemand_readahead() to think there's a
hole in the searched range and upsetting readahead logic.
Link: https://lkml.kernel.org/r/20240625101909.12234-2-jack@xxxxxxx
Signed-off-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/filemap.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/mm/filemap.c~filemap-fix-page_cache_next_miss-when-no-hole-found
+++ a/mm/filemap.c
@@ -1752,12 +1752,12 @@ pgoff_t page_cache_next_miss(struct addr
while (max_scan--) {
void *entry = xas_next(&xas);
if (!entry || xa_is_value(entry))
- break;
+ return xas.xa_index;
if (xas.xa_index == 0)
- break;
+ return 0;
}
- return xas.xa_index;
+ return index + max_scan;
}
EXPORT_SYMBOL(page_cache_next_miss);
_
Patches currently in -mm which might be from jack@xxxxxxx are
revert-mm-writeback-fix-possible-divide-by-zero-in-wb_dirty_limits-again.patch
mm-avoid-overflows-in-dirty-throttling-logic.patch
readahead-make-sure-sync-readahead-reads-needed-page.patch
filemap-fix-page_cache_next_miss-when-no-hole-found.patch
readahead-properly-shorten-readahead-when-falling-back-to-do_page_cache_ra.patch
readahead-drop-pointless-index-from-force_page_cache_ra.patch
readahead-drop-index-argument-of-page_cache_async_readahead.patch
readahead-drop-dead-code-in-page_cache_ra_order.patch
readahead-drop-dead-code-in-ondemand_readahead.patch
readahead-disentangle-async-and-sync-readahead.patch
readahead-fold-try_context_readahead-into-its-single-caller.patch
readahead-simplify-gotos-in-page_cache_sync_ra.patch
