diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-07-27 01:26:18 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-27 02:19:19 +0300 |
| commit | 800d8c63b2e989c2e349632d1648119bf5862f01 (patch) | |
| tree | 8f72ce10bcdc01f17a5e8f2197ae4858fbab6bd4 /include/linux | |
| parent | c01d5b300774d130a24d787825b01eb24e6e20cb (diff) | |
| download | linux-800d8c63b2e989c2e349632d1648119bf5862f01.tar.xz | |
shmem: add huge pages support
Here's basic implementation of huge pages support for shmem/tmpfs.
It's all pretty streight-forward:
- shmem_getpage() allcoates huge page if it can and try to inserd into
radix tree with shmem_add_to_page_cache();
- shmem_add_to_page_cache() puts the page onto radix-tree if there's
space for it;
- shmem_undo_range() removes huge pages, if it fully within range.
Partial truncate of huge pages zero out this part of THP.
This have visible effect on fallocate(FALLOC_FL_PUNCH_HOLE)
behaviour. As we don't really create hole in this case,
lseek(SEEK_HOLE) may have inconsistent results depending what
pages happened to be allocated.
- no need to change shmem_fault: core-mm will map an compound page as
huge if VMA is suitable;
Link: http://lkml.kernel.org/r/1466021202-61880-30-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/huge_mm.h | 2 | ||||
| -rw-r--r-- | include/linux/shmem_fs.h | 3 |
2 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 2f757132662a..7b7406e9fedf 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -156,6 +156,8 @@ void put_huge_zero_page(void); #define transparent_hugepage_enabled(__vma) 0 +static inline void prep_transhuge_page(struct page *page) {} + #define transparent_hugepage_flags 0UL static inline int split_huge_page_to_list(struct page *page, struct list_head *list) diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index ff2de4bab61f..94eaaa2c6ad9 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -71,6 +71,9 @@ static inline struct page *shmem_read_mapping_page( mapping_gfp_mask(mapping)); } +extern bool shmem_charge(struct inode *inode, long pages); +extern void shmem_uncharge(struct inode *inode, long pages); + #ifdef CONFIG_TMPFS extern int shmem_add_seals(struct file *file, unsigned int seals); |