diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index b7a72f577aab..907f6405e805 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -973,15 +973,9 @@ static int hugetlbfs_migrate_page(struct address_space *mapping, if (rc != MIGRATEPAGE_SUCCESS) return rc; - /* - * page_private is subpool pointer in hugetlb pages. Transfer to - * new page. PagePrivate is not associated with page_private for - * hugetlb pages and can not be set here as only page_huge_active - * pages can be migrated. - */ - if (page_private(page)) { - set_page_private(newpage, page_private(page)); - set_page_private(page, 0); + if (hugetlb_page_subpool(page)) { + hugetlb_set_page_subpool(newpage, hugetlb_page_subpool(page)); + hugetlb_set_page_subpool(page, NULL); } if (mode != MIGRATE_SYNC_NO_COPY) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index ac3cb239a7ec..249c65e1d8ca 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -472,6 +472,60 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long flags); #endif /* HAVE_ARCH_HUGETLB_UNMAPPED_AREA */ +/* + * huegtlb page specific state flags. These flags are located in page.private + * of the hugetlb head page. Functions created via the below macros should be + * used to manipulate these flags. + * + * HPG_restore_reserve - Set when a hugetlb page consumes a reservation at + * allocation time. Cleared when page is fully instantiated. Free + * routine checks flag to restore a reservation on error paths. + */ +enum hugetlb_page_flags { + HPG_restore_reserve = 0, + __NR_HPAGEFLAGS, +}; + +/* + * Macros to create test, set and clear function definitions for + * hugetlb specific page flags. + */ +#ifdef CONFIG_HUGETLB_PAGE +#define TESTHPAGEFLAG(uname, flname) \ +static inline int HPage##uname(struct page *page) \ + { return test_bit(HPG_##flname, &(page->private)); } + +#define SETHPAGEFLAG(uname, flname) \ +static inline void SetHPage##uname(struct page *page) \ + { set_bit(HPG_##flname, &(page->private)); } + +#define CLEARHPAGEFLAG(uname, flname) \ +static inline void ClearHPage##uname(struct page *page) \ + { clear_bit(HPG_##flname, &(page->private)); } +#else +#define TESTHPAGEFLAG(uname, flname) \ +static inline int HPage##uname(struct page *page) \ + { return 0; } + +#define SETHPAGEFLAG(uname, flname) \ +static inline void SetHPage##uname(struct page *page) \ + { } + +#define CLEARHPAGEFLAG(uname, flname) \ +static inline void ClearHPage##uname(struct page *page) \ + { } +#endif + +#define HPAGEFLAG(uname, flname) \ + TESTHPAGEFLAG(uname, flname) \ + SETHPAGEFLAG(uname, flname) \ + CLEARHPAGEFLAG(uname, flname) \ + +/* + * Create functions associated with hugetlb page flags + */ +HPAGEFLAG(RestoreReserve, restore_reserve) + #ifdef CONFIG_HUGETLB_PAGE #define HSTATE_NAME_LEN 32 @@ -531,6 +585,20 @@ extern unsigned int default_hstate_idx; #define default_hstate (hstates[default_hstate_idx]) +/* + * hugetlb page subpool pointer located in hpage[1].private + */ +static inline struct hugepage_subpool *hugetlb_page_subpool(struct page *hpage) +{ + return (struct hugepage_subpool *)(hpage+1)->private; +} + +static inline void hugetlb_set_page_subpool(struct page *hpage, + struct hugepage_subpool *subpool) +{ + set_page_private(hpage+1, (unsigned long)subpool); +} + static inline struct hstate *hstate_file(struct file *f) { return hstate_inode(file_inode(f)); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 8a1d1f85e21e..f5e85dabb7a3 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1143,7 +1143,7 @@ static struct page *dequeue_huge_page_vma(struct hstate *h, nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask); page = dequeue_huge_page_nodemask(h, gfp_mask, nid, nodemask); if (page && !avoid_reserve && vma_has_reserves(vma, chg)) { - SetPagePrivate(page); + SetHPageRestoreReserve(page); h->resv_huge_pages--; } @@ -1418,20 +1418,19 @@ static void __free_huge_page(struct page *page) */ struct hstate *h = page_hstate(page); int nid = page_to_nid(page); - struct hugepage_subpool *spool = - (struct hugepage_subpool *)page_private(page); + struct hugepage_subpool *spool = hugetlb_page_subpool(page); bool restore_reserve; VM_BUG_ON_PAGE(page_count(page), page); VM_BUG_ON_PAGE(page_mapcount(page), page); - set_page_private(page, 0); + hugetlb_set_page_subpool(page, NULL); page->mapping = NULL; - restore_reserve = PagePrivate(page); - ClearPagePrivate(page); + restore_reserve = HPageRestoreReserve(page); + ClearHPageRestoreReserve(page); /* - * If PagePrivate() was set on page, page allocation consumed a + * If HPageRestoreReserve was set on page, page allocation consumed a * reservation. If the page was associated with a subpool, there * would have been a page reserved in the subpool before allocation * via hugepage_subpool_get_pages(). Since we are 'restoring' the @@ -2263,24 +2262,24 @@ static long vma_add_reservation(struct hstate *h, * This routine is called to restore a reservation on error paths. In the * specific error paths, a huge page was allocated (via alloc_huge_page) * and is about to be freed. If a reservation for the page existed, - * alloc_huge_page would have consumed the reservation and set PagePrivate - * in the newly allocated page. When the page is freed via free_huge_page, - * the global reservation count will be incremented if PagePrivate is set. - * However, free_huge_page can not adjust the reserve map. Adjust the - * reserve map here to be consistent with global reserve count adjustments - * to be made by free_huge_page. + * alloc_huge_page would have consumed the reservation and set + * HPageRestoreReserve in the newly allocated page. When the page is freed + * via free_huge_page, the global reservation count will be incremented if + * HPageRestoreReserve is set. However, free_huge_page can not adjust the + * reserve map. Adjust the reserve map here to be consistent with global + * reserve count adjustments to be made by free_huge_page. */ static void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, unsigned long address, struct page *page) { - if (unlikely(PagePrivate(page))) { + if (unlikely(HPageRestoreReserve(page))) { long rc = vma_needs_reservation(h, vma, address); if (unlikely(rc < 0)) { /* * Rare out of memory condition in reserve map - * manipulation. Clear PagePrivate so that + * manipulation. Clear HPageRestoreReserve so that * global reserve count will not be incremented * by free_huge_page. This will make it appear * as though the reservation for this page was @@ -2289,7 +2288,7 @@ static void restore_reserve_on_error(struct hstate *h, * is better than inconsistent global huge page * accounting of reserve counts. */ - ClearPagePrivate(page); + ClearHPageRestoreReserve(page); } else if (rc) { rc = vma_add_reservation(h, vma, address); if (unlikely(rc < 0)) @@ -2297,7 +2296,7 @@ static void restore_reserve_on_error(struct hstate *h, * See above comment about rare out of * memory condition. */ - ClearPagePrivate(page); + ClearHPageRestoreReserve(page); } else vma_end_reservation(h, vma, address); } @@ -2378,7 +2377,7 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, if (!page) goto out_uncharge_cgroup; if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) { - SetPagePrivate(page); + SetHPageRestoreReserve(page); h->resv_huge_pages--; } spin_lock(&hugetlb_lock); @@ -2396,7 +2395,7 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, spin_unlock(&hugetlb_lock); - set_page_private(page, (unsigned long)spool); + hugetlb_set_page_subpool(page, spool); map_commit = vma_commit_reservation(h, vma, addr); if (unlikely(map_chg > map_commit)) { @@ -3170,6 +3169,9 @@ static int __init hugetlb_init(void) { int i; + BUILD_BUG_ON(sizeof_field(struct page, private) * BITS_PER_BYTE < + __NR_HPAGEFLAGS); + if (!hugepages_supported()) { if (hugetlb_max_hstate || default_hstate_max_huge_pages) pr_warn("HugeTLB: huge pages not supported, ignoring associated command-line parameters\n"); @@ -4207,7 +4209,7 @@ retry_avoidcopy: spin_lock(ptl); ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { - ClearPagePrivate(new_page); + ClearHPageRestoreReserve(new_page); /* Break COW */ huge_ptep_clear_flush(vma, haddr, ptep); @@ -4274,7 +4276,7 @@ int huge_add_to_page_cache(struct page *page, struct address_space *mapping, if (err) return err; - ClearPagePrivate(page); + ClearHPageRestoreReserve(page); /* * set page dirty so that it will not be removed from cache/file @@ -4436,7 +4438,7 @@ retry: goto backout; if (anon_rmap) { - ClearPagePrivate(page); + ClearHPageRestoreReserve(page); hugepage_add_new_anon_rmap(page, vma, haddr); } else page_dup_rmap(page, true); @@ -4750,7 +4752,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, if (vm_shared) { page_dup_rmap(page, true); } else { - ClearPagePrivate(page); + ClearHPageRestoreReserve(page); hugepage_add_new_anon_rmap(page, dst_vma, dst_addr); }