From 6afdb859b71019143b8eecda02b8b29b03185055 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Wed, 24 Jun 2015 16:58:06 -0700 Subject: [PATCH] mm: do not ignore mapping_gfp_mask in page cache allocation paths page_cache_read, do_generic_file_read, __generic_file_splice_read and __ntfs_grab_cache_pages currently ignore mapping_gfp_mask when calling add_to_page_cache_lru which might cause recursion into fs down in the direct reclaim path if the mapping really relies on GFP_NOFS semantic. This doesn't seem to be the case now because page_cache_read (page fault path) doesn't seem to suffer from the reclaim recursion issues and do_generic_file_read and __generic_file_splice_read also shouldn't be called under fs locks which would deadlock in the reclaim path. Anyway it is better to obey mapping gfp mask and prevent from later breakage. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Michal Hocko Cc: Dave Chinner Cc: Neil Brown Cc: Johannes Weiner Cc: Al Viro Cc: Mel Gorman Cc: Rik van Riel Cc: Tetsuo Handa Cc: Anton Altaparmakov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ntfs/file.c | 3 ++- fs/splice.c | 2 +- mm/filemap.c | 7 ++++--- 3 files changed, 7 insertions(+), 5 deletions(-) diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c index 7bb487e663b4..2cd653670764 100644 --- a/fs/ntfs/file.c +++ b/fs/ntfs/file.c @@ -525,7 +525,8 @@ static inline int __ntfs_grab_cache_pages(struct address_space *mapping, } } err = add_to_page_cache_lru(*cached_page, mapping, - index, GFP_KERNEL); + index, + GFP_KERNEL & mapping_gfp_mask(mapping)); if (unlikely(err)) { if (err == -EEXIST) continue; diff --git a/fs/splice.c b/fs/splice.c index bfe62ae40f40..0efef17e9bfa 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -359,7 +359,7 @@ __generic_file_splice_read(struct file *in, loff_t *ppos, break; error = add_to_page_cache_lru(page, mapping, index, - GFP_KERNEL); + GFP_KERNEL & mapping_gfp_mask(mapping)); if (unlikely(error)) { page_cache_release(page); if (error == -EEXIST) diff --git a/mm/filemap.c b/mm/filemap.c index 519af0045b1c..8d17ceea8dbe 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1664,8 +1664,8 @@ static ssize_t do_generic_file_read(struct file *filp, loff_t *ppos, error = -ENOMEM; goto out; } - error = add_to_page_cache_lru(page, mapping, - index, GFP_KERNEL); + error = add_to_page_cache_lru(page, mapping, index, + GFP_KERNEL & mapping_gfp_mask(mapping)); if (error) { page_cache_release(page); if (error == -EEXIST) { @@ -1766,7 +1766,8 @@ static int page_cache_read(struct file *file, pgoff_t offset) if (!page) return -ENOMEM; - ret = add_to_page_cache_lru(page, mapping, offset, GFP_KERNEL); + ret = add_to_page_cache_lru(page, mapping, offset, + GFP_KERNEL & mapping_gfp_mask(mapping)); if (ret == 0) ret = mapping->a_ops->readpage(file, page); else if (ret == -EEXIST)