io_uring: return locked and pinned page accounting

Locked and pinned memory accounting in io_{,un}account_mem() depends on
having ->sqo_mm, which is NULL after a recent change for non SQPOLL'ed
io_ring. That disables the accounting.

Return ->sqo_mm initialisation back, and do __io_sq_thread_acquire_mm()
based on IORING_SETUP_SQPOLL flag.

Fixes: 8eb06d7e8d ("io_uring: fix missing ->mm on exit")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2020-07-18 11:31:21 +03:00 committed by Jens Axboe
parent 5dbcad51f7
commit cbcf72148d
1 changed files with 5 additions and 4 deletions

View File

@ -981,7 +981,8 @@ static void io_sq_thread_drop_mm(void)
static int __io_sq_thread_acquire_mm(struct io_ring_ctx *ctx) static int __io_sq_thread_acquire_mm(struct io_ring_ctx *ctx)
{ {
if (!current->mm) { if (!current->mm) {
if (unlikely(!ctx->sqo_mm || !mmget_not_zero(ctx->sqo_mm))) if (unlikely(!(ctx->flags & IORING_SETUP_SQPOLL) ||
!mmget_not_zero(ctx->sqo_mm)))
return -EFAULT; return -EFAULT;
kthread_use_mm(ctx->sqo_mm); kthread_use_mm(ctx->sqo_mm);
} }
@ -7259,10 +7260,10 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx,
{ {
int ret; int ret;
if (ctx->flags & IORING_SETUP_SQPOLL) { mmgrab(current->mm);
mmgrab(current->mm); ctx->sqo_mm = current->mm;
ctx->sqo_mm = current->mm;
if (ctx->flags & IORING_SETUP_SQPOLL) {
ret = -EPERM; ret = -EPERM;
if (!capable(CAP_SYS_ADMIN)) if (!capable(CAP_SYS_ADMIN))
goto err; goto err;