[PATCH v10 02/25] mm/gup: move try_get_compound_head() to top, fix minor issues
From: John Hubbard <jhubbard@nvidia.com>
Date: 2019-12-12 08:22:51
Also in:
bpf, dri-devel, kvm, linux-block, linux-fsdevel, linux-kselftest, linux-media, linux-mm, linux-rdma, linuxppc-dev, lkml, netdev
Subsystem:
memory management, memory management - gup (get user pages), the rest · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds
An upcoming patch uses try_get_compound_head() more widely, so move it to the top of gup.c. Also fix a tiny spelling error and a checkpatch.pl warning. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: John Hubbard <jhubbard@nvidia.com> --- mm/gup.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-)
diff --git a/mm/gup.c b/mm/gup.c
index f764432914c4..3ecce297a47f 100644
--- a/mm/gup.c
+++ b/mm/gup.c@@ -29,6 +29,21 @@ struct follow_page_context { unsigned int page_mask; }; +/* + * Return the compound head page with ref appropriately incremented, + * or NULL if that failed. + */ +static inline struct page *try_get_compound_head(struct page *page, int refs) +{ + struct page *head = compound_head(page); + + if (WARN_ON_ONCE(page_ref_count(head) < 0)) + return NULL; + if (unlikely(!page_cache_add_speculative(head, refs))) + return NULL; + return head; +} + /** * put_user_pages_dirty_lock() - release and optionally dirty gup-pinned pages * @pages: array of pages to be maybe marked dirty, and definitely released.
@@ -1807,20 +1822,6 @@ static void __maybe_unused undo_dev_pagemap(int *nr, int nr_start, } } -/* - * Return the compund head page with ref appropriately incremented, - * or NULL if that failed. - */ -static inline struct page *try_get_compound_head(struct page *page, int refs) -{ - struct page *head = compound_head(page); - if (WARN_ON_ONCE(page_ref_count(head) < 0)) - return NULL; - if (unlikely(!page_cache_add_speculative(head, refs))) - return NULL; - return head; -} - #ifdef CONFIG_ARCH_HAS_PTE_SPECIAL static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, unsigned int flags, struct page **pages, int *nr)
--
2.24.0