From e7392b4eca84e86718a7b73aea8fa5573b06ba76 Mon Sep 17 00:00:00 2001 From: "Fabio M. De Francesco" Date: Fri, 13 May 2022 16:48:55 -0700 Subject: mm/highmem: fix kernel-doc warnings in highmem*.h Patch series "Extend and reorganize Highmem's documentation", v4. This series has the purpose to extend and reorganize Highmem's documentation. This is a work in progress because some information should still be moved from highmem.rst to highmem.h and highmem-internal.h. Specifically I'm talking about moving the "how to" information to the relevant headers, as it as been suggested by Ira Weiny (Intel). Also, this is a work in progress because some kdocs in highmem.h and highmem-internal.h should be improved. This patch (of 4): `scripts/kernel-doc -v -none include/linux/highmem*` reports the following warnings: include/linux/highmem.h:160: warning: expecting prototype for kunmap_atomic(). Prototype was for nr_free_highpages() instead include/linux/highmem.h:204: warning: No description found for return value of 'alloc_zeroed_user_highpage_movable' include/linux/highmem-internal.h:256: warning: Function parameter or member '__addr' not described in 'kunmap_atomic' include/linux/highmem-internal.h:256: warning: Excess function parameter 'addr' description in 'kunmap_atomic' Fix these warnings by (1) moving the kernel-doc comments from highmem.h to highmem-internal.h (which is the file were the kunmap_atomic() macro is actually defined), (2) extending and merging it with the comment which was already in highmem-internal.h, and (3) using correct parameter names (4) correcting a few technical inaccuracies in comments, and (5) adding a deprecation notice in kunmap_atomic() for consistency with kmap_atomic(). Link: https://lkml.kernel.org/r/20220428212455.892-1-fmdefrancesco@gmail.com Link: https://lkml.kernel.org/r/20220428212455.892-2-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco Reviewed-by: Sebastian Andrzej Siewior Reviewed-by: Ira Weiny Cc: Matthew Wilcox Cc: Mike Rapoport Cc: Catalin Marinas Cc: Will Deacon Cc: Peter Collingbourne Cc: Vlastimil Babka Cc: Jonathan Corbet Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Jonathan Corbet Signed-off-by: Andrew Morton --- include/linux/highmem-internal.h | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'include/linux/highmem-internal.h') diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h index a77be5630209..a694ca95c4ed 100644 --- a/include/linux/highmem-internal.h +++ b/include/linux/highmem-internal.h @@ -236,9 +236,21 @@ static inline unsigned long totalhigh_pages(void) { return 0UL; } #endif /* CONFIG_HIGHMEM */ -/* - * Prevent people trying to call kunmap_atomic() as if it were kunmap() - * kunmap_atomic() should get the return value of kmap_atomic, not the page. +/** + * kunmap_atomic - Unmap the virtual address mapped by kmap_atomic() - deprecated! + * @__addr: Virtual address to be unmapped + * + * Unmaps an address previously mapped by kmap_atomic() and re-enables + * pagefaults. Depending on PREEMP_RT configuration, re-enables also + * migration and preemption. Users should not count on these side effects. + * + * Mappings should be unmapped in the reverse order that they were mapped. + * See kmap_local_page() for details on nesting. + * + * @__addr can be any address within the mapped page, so there is no need + * to subtract any offset that has been added. In contrast to kunmap(), + * this function takes the address returned from kmap_atomic(), not the + * page passed to it. The compiler will warn you if you pass the page. */ #define kunmap_atomic(__addr) \ do { \ -- cgit v1.2.3