diff options
| author | Xu Yang <xu.yang_2@nxp.com> | 2024-05-21 19:49:38 +0800 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2024-05-24 13:34:06 +0200 |
| commit | 79c137454815ba5554caa8eeb4ad5c94e96e45ce (patch) | |
| tree | 38fc379b500250850b6d0193cd0dc860638530a1 | |
| parent | 2c6b531020f0590db3b6b4950a41c692e9aa4f4a (diff) | |
filemap: add helper mapping_max_folio_size()
Add mapping_max_folio_size() to get the maximum folio size for this
pagecache mapping.
Fixes: 5d8edfb900d5 ("iomap: Copy larger chunks from userspace")
Cc: stable@vger.kernel.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20240521114939.2541461-1-xu.yang_2@nxp.com
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
| -rw-r--r-- | include/linux/pagemap.h | 34 |
1 files changed, 21 insertions, 13 deletions
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 3d69589c00a4..ee633712bba0 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -346,6 +346,19 @@ static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) m->gfp_mask = mask; } +/* + * There are some parts of the kernel which assume that PMD entries + * are exactly HPAGE_PMD_ORDER. Those should be fixed, but until then, + * limit the maximum allocation order to PMD size. I'm not aware of any + * assumptions about maximum order if THP are disabled, but 8 seems like + * a good order (that's 1MB if you're using 4kB pages) + */ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#define MAX_PAGECACHE_ORDER HPAGE_PMD_ORDER +#else +#define MAX_PAGECACHE_ORDER 8 +#endif + /** * mapping_set_large_folios() - Indicate the file supports large folios. * @mapping: The file. @@ -372,6 +385,14 @@ static inline bool mapping_large_folio_support(struct address_space *mapping) test_bit(AS_LARGE_FOLIO_SUPPORT, &mapping->flags); } +/* Return the maximum folio size for this pagecache mapping, in bytes. */ +static inline size_t mapping_max_folio_size(struct address_space *mapping) +{ + if (mapping_large_folio_support(mapping)) + return PAGE_SIZE << MAX_PAGECACHE_ORDER; + return PAGE_SIZE; +} + static inline int filemap_nr_thps(struct address_space *mapping) { #ifdef CONFIG_READ_ONLY_THP_FOR_FS @@ -530,19 +551,6 @@ static inline void *detach_page_private(struct page *page) return folio_detach_private(page_folio(page)); } -/* - * There are some parts of the kernel which assume that PMD entries - * are exactly HPAGE_PMD_ORDER. Those should be fixed, but until then, - * limit the maximum allocation order to PMD size. I'm not aware of any - * assumptions about maximum order if THP are disabled, but 8 seems like - * a good order (that's 1MB if you're using 4kB pages) - */ -#ifdef CONFIG_TRANSPARENT_HUGEPAGE -#define MAX_PAGECACHE_ORDER HPAGE_PMD_ORDER -#else -#define MAX_PAGECACHE_ORDER 8 -#endif - #ifdef CONFIG_NUMA struct folio *filemap_alloc_folio_noprof(gfp_t gfp, unsigned int order); #else |