diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index f3726ba12aa6..9266271a787a 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -268,28 +268,38 @@ static void vfio_lock_acct(struct task_struct *task, long npage) { struct vwork *vwork; struct mm_struct *mm; + bool is_current; if (!npage) return; - mm = get_task_mm(task); + is_current = (task->mm == current->mm); + + mm = is_current ? task->mm : get_task_mm(task); if (!mm) - return; /* process exited or nothing to do */ + return; /* process exited */ if (down_write_trylock(&mm->mmap_sem)) { mm->locked_vm += npage; up_write(&mm->mmap_sem); - mmput(mm); + if (!is_current) + mmput(mm); return; } + if (is_current) { + mm = get_task_mm(task); + if (!mm) + return; + } + /* * Couldn't get mmap_sem lock, so must setup to update * mm->locked_vm later. If locked_vm were atomic, we * wouldn't need this silliness */ vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL); - if (!vwork) { + if (WARN_ON(!vwork)) { mmput(mm); return; } @@ -393,77 +403,71 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, static long vfio_pin_pages_remote(struct vfio_dma *dma, unsigned long vaddr, long npage, unsigned long *pfn_base) { - unsigned long limit; - bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns, - CAP_IPC_LOCK); - struct mm_struct *mm; - long ret, i = 0, lock_acct = 0; + unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; + bool lock_cap = capable(CAP_IPC_LOCK); + long ret, pinned = 0, lock_acct = 0; bool rsvd; dma_addr_t iova = vaddr - dma->vaddr + dma->iova; - mm = get_task_mm(dma->task); - if (!mm) + /* This code path is only user initiated */ + if (!current->mm) return -ENODEV; - ret = vaddr_get_pfn(mm, vaddr, dma->prot, pfn_base); + ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, pfn_base); if (ret) - goto pin_pg_remote_exit; + return ret; + pinned++; rsvd = is_invalid_reserved_pfn(*pfn_base); - limit = task_rlimit(dma->task, RLIMIT_MEMLOCK) >> PAGE_SHIFT; /* * Reserved pages aren't counted against the user, externally pinned * pages are already counted against the user. */ if (!rsvd && !vfio_find_vpfn(dma, iova)) { - if (!lock_cap && mm->locked_vm + 1 > limit) { + if (!lock_cap && current->mm->locked_vm + 1 > limit) { put_pfn(*pfn_base, dma->prot); pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__, limit << PAGE_SHIFT); - ret = -ENOMEM; - goto pin_pg_remote_exit; + return -ENOMEM; } lock_acct++; } - i++; - if (likely(!disable_hugepages)) { - /* Lock all the consecutive pages from pfn_base */ - for (vaddr += PAGE_SIZE, iova += PAGE_SIZE; i < npage; - i++, vaddr += PAGE_SIZE, iova += PAGE_SIZE) { - unsigned long pfn = 0; + if (unlikely(disable_hugepages)) + goto out; - ret = vaddr_get_pfn(mm, vaddr, dma->prot, &pfn); - if (ret) - break; + /* Lock all the consecutive pages from pfn_base */ + for (vaddr += PAGE_SIZE, iova += PAGE_SIZE; pinned < npage; + pinned++, vaddr += PAGE_SIZE, iova += PAGE_SIZE) { + unsigned long pfn = 0; - if (pfn != *pfn_base + i || - rsvd != is_invalid_reserved_pfn(pfn)) { + ret = vaddr_get_pfn(current->mm, vaddr, dma->prot, &pfn); + if (ret) + break; + + if (pfn != *pfn_base + pinned || + rsvd != is_invalid_reserved_pfn(pfn)) { + put_pfn(pfn, dma->prot); + break; + } + + if (!rsvd && !vfio_find_vpfn(dma, iova)) { + if (!lock_cap && + current->mm->locked_vm + lock_acct + 1 > limit) { put_pfn(pfn, dma->prot); + pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", + __func__, limit << PAGE_SHIFT); break; } - - if (!rsvd && !vfio_find_vpfn(dma, iova)) { - if (!lock_cap && - mm->locked_vm + lock_acct + 1 > limit) { - put_pfn(pfn, dma->prot); - pr_warn("%s: RLIMIT_MEMLOCK (%ld) " - "exceeded\n", __func__, - limit << PAGE_SHIFT); - break; - } - lock_acct++; - } + lock_acct++; } } - vfio_lock_acct(dma->task, lock_acct); - ret = i; +out: + vfio_lock_acct(current, lock_acct); -pin_pg_remote_exit: - mmput(mm); - return ret; + return pinned; } static long vfio_unpin_pages_remote(struct vfio_dma *dma, dma_addr_t iova, @@ -473,10 +477,10 @@ static long vfio_unpin_pages_remote(struct vfio_dma *dma, dma_addr_t iova, long unlocked = 0, locked = 0; long i; - for (i = 0; i < npage; i++) { + for (i = 0; i < npage; i++, iova += PAGE_SIZE) { if (put_pfn(pfn++, dma->prot)) { unlocked++; - if (vfio_find_vpfn(dma, iova + (i << PAGE_SHIFT))) + if (vfio_find_vpfn(dma, iova)) locked++; } }