diff options
Diffstat (limited to 'mm/shmem.c')
| -rw-r--r-- | mm/shmem.c | 29 |
1 files changed, 17 insertions, 12 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 220be9fa2c41..165fa6332993 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1369,7 +1369,8 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) if (list_empty(&info->swaplist)) list_add(&info->swaplist, &shmem_swaplist); - if (add_to_swap_cache(page, swap, GFP_ATOMIC) == 0) { + if (add_to_swap_cache(page, swap, + __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN) == 0) { spin_lock_irq(&info->lock); shmem_recalc_inode(inode); info->swapped++; @@ -2022,16 +2023,14 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) shmem_falloc->waitq && vmf->pgoff >= shmem_falloc->start && vmf->pgoff < shmem_falloc->next) { + struct file *fpin; wait_queue_head_t *shmem_falloc_waitq; DEFINE_WAIT_FUNC(shmem_fault_wait, synchronous_wake_function); ret = VM_FAULT_NOPAGE; - if ((vmf->flags & FAULT_FLAG_ALLOW_RETRY) && - !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) { - /* It's polite to up mmap_sem if we can */ - up_read(&vma->vm_mm->mmap_sem); + fpin = maybe_unlock_mmap_for_io(vmf, NULL); + if (fpin) ret = VM_FAULT_RETRY; - } shmem_falloc_waitq = shmem_falloc->waitq; prepare_to_wait(shmem_falloc_waitq, &shmem_fault_wait, @@ -2049,6 +2048,9 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) spin_lock(&inode->i_lock); finish_wait(shmem_falloc_waitq, &shmem_fault_wait); spin_unlock(&inode->i_lock); + + if (fpin) + fput(fpin); return ret; } spin_unlock(&inode->i_lock); @@ -2213,11 +2215,14 @@ static int shmem_mmap(struct file *file, struct vm_area_struct *vma) return -EPERM; /* - * Since the F_SEAL_FUTURE_WRITE seals allow for a MAP_SHARED - * read-only mapping, take care to not allow mprotect to revert - * protections. + * Since an F_SEAL_FUTURE_WRITE sealed memfd can be mapped as + * MAP_SHARED and read-only, take care to not allow mprotect to + * revert protections on such mappings. Do this only for shared + * mappings. For private mappings, don't need to mask + * VM_MAYWRITE as we still want them to be COW-writable. */ - vma->vm_flags &= ~(VM_MAYWRITE); + if (vma->vm_flags & VM_SHARED) + vma->vm_flags &= ~(VM_MAYWRITE); } file_accessed(file); @@ -2742,7 +2747,7 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset, } shmem_falloc.waitq = &shmem_falloc_waitq; - shmem_falloc.start = unmap_start >> PAGE_SHIFT; + shmem_falloc.start = (u64)unmap_start >> PAGE_SHIFT; shmem_falloc.next = (unmap_end + 1) >> PAGE_SHIFT; spin_lock(&inode->i_lock); inode->i_private = &shmem_falloc; @@ -3928,7 +3933,7 @@ out2: static ssize_t shmem_enabled_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - int values[] = { + static const int values[] = { SHMEM_HUGE_ALWAYS, SHMEM_HUGE_WITHIN_SIZE, SHMEM_HUGE_ADVISE, |