-stable review patch. If anyone has any objections, please let us know.
------------------
2.6.15's hugepage faulting introduced huge_pages_needed accounting into
hugetlbfs: to count how many pages are already in cache, for spot check
on how far a new mapping may be allowed to extend the file. But it's
muddled: each hugepage found covers HPAGE_SIZE, not PAGE_SIZE. Once
pages were already in cache, it would overshoot, wrap its hugepages
count backwards, and so fail a harmless repeat mapping with -ENOMEM.
Fixes the problem found by Don Dupuis.
Signed-off-by: Hugh Dickins <[email protected]>
Acked-By: Adam Litke <[email protected]>
Acked-by: William Irwin <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
fs/hugetlbfs/inode.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
--- linux-2.6.15.4.orig/fs/hugetlbfs/inode.c
+++ linux-2.6.15.4/fs/hugetlbfs/inode.c
@@ -71,8 +71,8 @@ huge_pages_needed(struct address_space *
unsigned long start = vma->vm_start;
unsigned long end = vma->vm_end;
unsigned long hugepages = (end - start) >> HPAGE_SHIFT;
- pgoff_t next = vma->vm_pgoff;
- pgoff_t endpg = next + ((end - start) >> PAGE_SHIFT);
+ pgoff_t next = vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT);
+ pgoff_t endpg = next + hugepages;
pagevec_init(&pvec, 0);
while (next < endpg) {
--