From 09cbfeaf1a5a67bfb3201e0c83c810cecb2efa5a Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 1 Apr 2016 15:29:47 +0300 Subject: mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ; - >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov Acked-by: Michal Hocko Signed-off-by: Linus Torvalds --- include/linux/pagemap.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'include/linux/pagemap.h') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 1ebd65c..f396ccb 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -390,13 +390,13 @@ static inline pgoff_t page_to_pgoff(struct page *page) return page->index << compound_order(page); if (likely(!PageTransTail(page))) - return page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); + return page->index; /* * We don't initialize ->index for tail pages: calculate based on * head page */ - pgoff = compound_head(page)->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); + pgoff = compound_head(page)->index; pgoff += page - compound_head(page); return pgoff; } @@ -406,12 +406,12 @@ static inline pgoff_t page_to_pgoff(struct page *page) */ static inline loff_t page_offset(struct page *page) { - return ((loff_t)page->index) << PAGE_CACHE_SHIFT; + return ((loff_t)page->index) << PAGE_SHIFT; } static inline loff_t page_file_offset(struct page *page) { - return ((loff_t)page_file_index(page)) << PAGE_CACHE_SHIFT; + return ((loff_t)page_file_index(page)) << PAGE_SHIFT; } extern pgoff_t linear_hugepage_index(struct vm_area_struct *vma, @@ -425,7 +425,7 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma, return linear_hugepage_index(vma, address); pgoff = (address - vma->vm_start) >> PAGE_SHIFT; pgoff += vma->vm_pgoff; - return pgoff >> (PAGE_CACHE_SHIFT - PAGE_SHIFT); + return pgoff; } extern void __lock_page(struct page *page); @@ -671,8 +671,8 @@ static inline int add_to_page_cache(struct page *page, static inline unsigned long dir_pages(struct inode *inode) { - return (unsigned long)(inode->i_size + PAGE_CACHE_SIZE - 1) >> - PAGE_CACHE_SHIFT; + return (unsigned long)(inode->i_size + PAGE_SIZE - 1) >> + PAGE_SHIFT; } #endif /* _LINUX_PAGEMAP_H */ -- cgit v1.1 From ea1754a084760e68886f5b725c8eaada9cc57155 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 1 Apr 2016 15:29:48 +0300 Subject: mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage Mostly direct substitution with occasional adjustment or removing outdated comments. Signed-off-by: Kirill A. Shutemov Acked-by: Michal Hocko Signed-off-by: Linus Torvalds --- include/linux/pagemap.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/linux/pagemap.h') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index f396ccb..b3fc037 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -535,8 +535,7 @@ extern void add_page_wait_queue(struct page *page, wait_queue_t *waiter); /* * Fault a userspace page into pagetables. Return non-zero on a fault. * - * This assumes that two userspace pages are always sufficient. That's - * not true if PAGE_CACHE_SIZE > PAGE_SIZE. + * This assumes that two userspace pages are always sufficient. */ static inline int fault_in_pages_writeable(char __user *uaddr, int size) { -- cgit v1.1 From 1fa64f198b9f8d6ec0f7aec7c18dc94684391140 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Fri, 1 Apr 2016 15:29:49 +0300 Subject: mm: drop PAGE_CACHE_* and page_cache_{get,release} definition All users gone. We can remove these macros. Signed-off-by: Kirill A. Shutemov Acked-by: Michal Hocko Signed-off-by: Linus Torvalds --- include/linux/pagemap.h | 15 --------------- 1 file changed, 15 deletions(-) (limited to 'include/linux/pagemap.h') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index b3fc037..7e1ab15 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -86,21 +86,6 @@ static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) (__force unsigned long)mask; } -/* - * The page cache can be done in larger chunks than - * one page, because it allows for more efficient - * throughput (it can then be mapped into user - * space in smaller chunks for same flexibility). - * - * Or rather, it _will_ be done in larger chunks. - */ -#define PAGE_CACHE_SHIFT PAGE_SHIFT -#define PAGE_CACHE_SIZE PAGE_SIZE -#define PAGE_CACHE_MASK PAGE_MASK -#define PAGE_CACHE_ALIGN(addr) (((addr)+PAGE_CACHE_SIZE-1)&PAGE_CACHE_MASK) - -#define page_cache_get(page) get_page(page) -#define page_cache_release(page) put_page(page) void release_pages(struct page **pages, int nr, bool cold); /* -- cgit v1.1