aboutsummaryrefslogtreecommitdiffstats
path: root/mm/hugetlb.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2010-08-12 17:15:10 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2010-08-12 17:15:10 (GMT)
commit1021a645344d4a77333e19e60d37b9343be0d7b7 (patch)
tree7a78ab55f27f97209ed1b85ccfd88c6d5b8416d3 /mm/hugetlb.c
parent7367f5b013fee33f7d40a5a10a39d5134f529ec8 (diff)
parent28957a5467bab9ed51a237d21e31055fad987887 (diff)
Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: hugetlb: add missing unlock in avoidcopy path in hugetlb_cow() hwpoison: rename CONFIG HWPOISON, hugetlb: support hwpoison injection for hugepage HWPOISON, hugetlb: detect hwpoison in hugetlb code HWPOISON, hugetlb: isolate corrupted hugepage HWPOISON, hugetlb: maintain mce_bad_pages in handling hugepage error HWPOISON, hugetlb: set/clear PG_hwpoison bits on hugepage HWPOISON, hugetlb: enable error handling path for hugepage hugetlb, rmap: add reverse mapping for hugepage hugetlb: move definition of is_vm_hugetlb_page() to hugepage_inline.h Fix up trivial conflicts in mm/memory-failure.c
Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r--mm/hugetlb.c104
1 files changed, 102 insertions, 2 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index b61d2db..cc5be78 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -18,6 +18,9 @@
#include <linux/bootmem.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
+#include <linux/rmap.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
#include <asm/page.h>
#include <asm/pgtable.h>
@@ -220,6 +223,12 @@ static pgoff_t vma_hugecache_offset(struct hstate *h,
(vma->vm_pgoff >> huge_page_order(h));
}
+pgoff_t linear_hugepage_index(struct vm_area_struct *vma,
+ unsigned long address)
+{
+ return vma_hugecache_offset(hstate_vma(vma), vma, address);
+}
+
/*
* Return the size of the pages allocated when backing a VMA. In the majority
* cases this will be same size as used by the page table entries.
@@ -552,6 +561,7 @@ static void free_huge_page(struct page *page)
set_page_private(page, 0);
page->mapping = NULL;
BUG_ON(page_count(page));
+ BUG_ON(page_mapcount(page));
INIT_LIST_HEAD(&page->lru);
spin_lock(&hugetlb_lock);
@@ -605,6 +615,8 @@ int PageHuge(struct page *page)
return dtor == free_huge_page;
}
+EXPORT_SYMBOL_GPL(PageHuge);
+
static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid)
{
struct page *page;
@@ -2129,6 +2141,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
entry = huge_ptep_get(src_pte);
ptepage = pte_page(entry);
get_page(ptepage);
+ page_dup_rmap(ptepage);
set_huge_pte_at(dst, addr, dst_pte, entry);
}
spin_unlock(&src->page_table_lock);
@@ -2140,6 +2153,19 @@ nomem:
return -ENOMEM;
}
+static int is_hugetlb_entry_hwpoisoned(pte_t pte)
+{
+ swp_entry_t swp;
+
+ if (huge_pte_none(pte) || pte_present(pte))
+ return 0;
+ swp = pte_to_swp_entry(pte);
+ if (non_swap_entry(swp) && is_hwpoison_entry(swp)) {
+ return 1;
+ } else
+ return 0;
+}
+
void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end, struct page *ref_page)
{
@@ -2198,6 +2224,12 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
if (huge_pte_none(pte))
continue;
+ /*
+ * HWPoisoned hugepage is already unmapped and dropped reference
+ */
+ if (unlikely(is_hugetlb_entry_hwpoisoned(pte)))
+ continue;
+
page = pte_page(pte);
if (pte_dirty(pte))
set_page_dirty(page);
@@ -2207,6 +2239,7 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
flush_tlb_range(vma, start, end);
mmu_notifier_invalidate_range_end(mm, start, end);
list_for_each_entry_safe(page, tmp, &page_list, lru) {
+ page_remove_rmap(page);
list_del(&page->lru);
put_page(page);
}
@@ -2272,6 +2305,9 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
return 1;
}
+/*
+ * Hugetlb_cow() should be called with page lock of the original hugepage held.
+ */
static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *ptep, pte_t pte,
struct page *pagecache_page)
@@ -2286,8 +2322,13 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
retry_avoidcopy:
/* If no-one else is actually using this page, avoid the copy
* and just make the page writable */
- avoidcopy = (page_count(old_page) == 1);
+ avoidcopy = (page_mapcount(old_page) == 1);
if (avoidcopy) {
+ if (!trylock_page(old_page)) {
+ if (PageAnon(old_page))
+ page_move_anon_rmap(old_page, vma, address);
+ } else
+ unlock_page(old_page);
set_huge_ptep_writable(vma, address, ptep);
return 0;
}
@@ -2338,6 +2379,13 @@ retry_avoidcopy:
return -PTR_ERR(new_page);
}
+ /*
+ * When the original hugepage is shared one, it does not have
+ * anon_vma prepared.
+ */
+ if (unlikely(anon_vma_prepare(vma)))
+ return VM_FAULT_OOM;
+
copy_huge_page(new_page, old_page, address, vma);
__SetPageUptodate(new_page);
@@ -2355,6 +2403,8 @@ retry_avoidcopy:
huge_ptep_clear_flush(vma, address, ptep);
set_huge_pte_at(mm, address, ptep,
make_huge_pte(vma, new_page, 1));
+ page_remove_rmap(old_page);
+ hugepage_add_anon_rmap(new_page, vma, address);
/* Make the old page be freed below */
new_page = old_page;
mmu_notifier_invalidate_range_end(mm,
@@ -2458,10 +2508,29 @@ retry:
spin_lock(&inode->i_lock);
inode->i_blocks += blocks_per_huge_page(h);
spin_unlock(&inode->i_lock);
+ page_dup_rmap(page);
} else {
lock_page(page);
- page->mapping = HUGETLB_POISON;
+ if (unlikely(anon_vma_prepare(vma))) {
+ ret = VM_FAULT_OOM;
+ goto backout_unlocked;
+ }
+ hugepage_add_new_anon_rmap(page, vma, address);
}
+ } else {
+ page_dup_rmap(page);
+ }
+
+ /*
+ * Since memory error handler replaces pte into hwpoison swap entry
+ * at the time of error handling, a process which reserved but not have
+ * the mapping to the error hugepage does not have hwpoison swap entry.
+ * So we need to block accesses from such a process by checking
+ * PG_hwpoison bit here.
+ */
+ if (unlikely(PageHWPoison(page))) {
+ ret = VM_FAULT_HWPOISON;
+ goto backout_unlocked;
}
/*
@@ -2513,10 +2582,18 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
pte_t *ptep;
pte_t entry;
int ret;
+ struct page *page = NULL;
struct page *pagecache_page = NULL;
static DEFINE_MUTEX(hugetlb_instantiation_mutex);
struct hstate *h = hstate_vma(vma);
+ ptep = huge_pte_offset(mm, address);
+ if (ptep) {
+ entry = huge_ptep_get(ptep);
+ if (unlikely(is_hugetlb_entry_hwpoisoned(entry)))
+ return VM_FAULT_HWPOISON;
+ }
+
ptep = huge_pte_alloc(mm, address, huge_page_size(h));
if (!ptep)
return VM_FAULT_OOM;
@@ -2554,6 +2631,11 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
vma, address);
}
+ if (!pagecache_page) {
+ page = pte_page(entry);
+ lock_page(page);
+ }
+
spin_lock(&mm->page_table_lock);
/* Check for a racing update before calling hugetlb_cow */
if (unlikely(!pte_same(entry, huge_ptep_get(ptep))))
@@ -2579,6 +2661,8 @@ out_page_table_lock:
if (pagecache_page) {
unlock_page(pagecache_page);
put_page(pagecache_page);
+ } else {
+ unlock_page(page);
}
out_mutex:
@@ -2791,3 +2875,19 @@ void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
hugetlb_put_quota(inode->i_mapping, (chg - freed));
hugetlb_acct_memory(h, -(chg - freed));
}
+
+/*
+ * This function is called from memory failure code.
+ * Assume the caller holds page lock of the head page.
+ */
+void __isolate_hwpoisoned_huge_page(struct page *hpage)
+{
+ struct hstate *h = page_hstate(hpage);
+ int nid = page_to_nid(hpage);
+
+ spin_lock(&hugetlb_lock);
+ list_del(&hpage->lru);
+ h->free_huge_pages--;
+ h->free_huge_pages_node[nid]--;
+ spin_unlock(&hugetlb_lock);
+}

Privacy Policy