diff options
Diffstat (limited to 'fs/io_uring.c')
-rw-r--r-- | fs/io_uring.c | 233 |
1 files changed, 134 insertions, 99 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 5a826017ebb8..3affd96a98ba 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -183,17 +183,12 @@ struct fixed_file_table { struct file **files; }; -enum { - FFD_F_ATOMIC, -}; - struct fixed_file_data { struct fixed_file_table *table; struct io_ring_ctx *ctx; struct percpu_ref refs; struct llist_head put_llist; - unsigned long state; struct work_struct ref_work; struct completion done; }; @@ -348,6 +343,7 @@ struct io_accept { struct sockaddr __user *addr; int __user *addr_len; int flags; + unsigned long nofile; }; struct io_sync { @@ -402,6 +398,7 @@ struct io_open { struct filename *filename; struct statx __user *buffer; struct open_how how; + unsigned long nofile; }; struct io_files_update { @@ -1004,6 +1001,7 @@ static void io_kill_timeout(struct io_kiocb *req) if (ret != -1) { atomic_inc(&req->ctx->cq_timeouts); list_del_init(&req->list); + req->flags |= REQ_F_COMP_LOCKED; io_cqring_fill_event(req, 0); io_put_req(req); } @@ -1260,6 +1258,9 @@ static void __io_req_aux_free(struct io_kiocb *req) { struct io_ring_ctx *ctx = req->ctx; + if (req->flags & REQ_F_NEED_CLEANUP) + io_cleanup_req(req); + kfree(req->io); if (req->file) { if (req->flags & REQ_F_FIXED_FILE) @@ -1275,9 +1276,6 @@ static void __io_free_req(struct io_kiocb *req) { __io_req_aux_free(req); - if (req->flags & REQ_F_NEED_CLEANUP) - io_cleanup_req(req); - if (req->flags & REQ_F_INFLIGHT) { struct io_ring_ctx *ctx = req->ctx; unsigned long flags; @@ -1483,10 +1481,10 @@ static void io_free_req(struct io_kiocb *req) __attribute__((nonnull)) static void io_put_req_find_next(struct io_kiocb *req, struct io_kiocb **nxtptr) { - io_req_find_next(req, nxtptr); - - if (refcount_dec_and_test(&req->refs)) + if (refcount_dec_and_test(&req->refs)) { + io_req_find_next(req, nxtptr); __io_free_req(req); + } } static void io_put_req(struct io_kiocb *req) @@ -1672,11 +1670,17 @@ static void io_iopoll_reap_events(struct io_ring_ctx *ctx) mutex_unlock(&ctx->uring_lock); } -static int __io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, - long min) +static int io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, + long min) { int iters = 0, ret = 0; + /* + * We disallow the app entering submit/complete with polling, but we + * still need to lock the ring to prevent racing with polled issue + * that got punted to a workqueue. + */ + mutex_lock(&ctx->uring_lock); do { int tmin = 0; @@ -1712,21 +1716,6 @@ static int __io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, ret = 0; } while (min && !*nr_events && !need_resched()); - return ret; -} - -static int io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, - long min) -{ - int ret; - - /* - * We disallow the app entering submit/complete with polling, but we - * still need to lock the ring to prevent racing with polled issue - * that got punted to a workqueue. - */ - mutex_lock(&ctx->uring_lock); - ret = __io_iopoll_check(ctx, nr_events, min); mutex_unlock(&ctx->uring_lock); return ret; } @@ -1830,6 +1819,10 @@ static void io_iopoll_req_issued(struct io_kiocb *req) list_add(&req->list, &ctx->poll_list); else list_add_tail(&req->list, &ctx->poll_list); + + if ((ctx->flags & IORING_SETUP_SQPOLL) && + wq_has_sleeper(&ctx->sqo_wait)) + wake_up(&ctx->sqo_wait); } static void io_file_put(struct io_submit_state *state) @@ -2080,7 +2073,7 @@ static ssize_t io_import_iovec(int rw, struct io_kiocb *req, ssize_t ret; ret = import_single_range(rw, buf, sqe_len, *iovec, iter); *iovec = NULL; - return ret; + return ret < 0 ? ret : sqe_len; } if (req->io) { @@ -2517,6 +2510,9 @@ static void io_fallocate_finish(struct io_wq_work **workptr) struct io_kiocb *nxt = NULL; int ret; + if (io_req_cancelled(req)) + return; + ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off, req->sync.len); if (ret < 0) @@ -2583,6 +2579,7 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return ret; } + req->open.nofile = rlimit(RLIMIT_NOFILE); req->flags |= REQ_F_NEED_CLEANUP; return 0; } @@ -2624,6 +2621,7 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return ret; } + req->open.nofile = rlimit(RLIMIT_NOFILE); req->flags |= REQ_F_NEED_CLEANUP; return 0; } @@ -2642,7 +2640,7 @@ static int io_openat2(struct io_kiocb *req, struct io_kiocb **nxt, if (ret) goto err; - ret = get_unused_fd_flags(req->open.how.flags); + ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile); if (ret < 0) goto err; @@ -2904,6 +2902,7 @@ static void io_close_finish(struct io_wq_work **workptr) struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); struct io_kiocb *nxt = NULL; + /* not cancellable, don't do io_req_cancelled() */ __io_close_finish(req, &nxt); if (nxt) io_wq_assign_next(workptr, nxt); @@ -3007,6 +3006,11 @@ static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr)); sr->len = READ_ONCE(sqe->len); +#ifdef CONFIG_COMPAT + if (req->ctx->compat) + sr->msg_flags |= MSG_CMSG_COMPAT; +#endif + if (!io || req->opcode == IORING_OP_SEND) return 0; /* iovec is already imported */ @@ -3071,7 +3075,7 @@ static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt, if (req->io) return -EAGAIN; if (io_alloc_async_ctx(req)) { - if (kmsg && kmsg->iov != kmsg->fast_iov) + if (kmsg->iov != kmsg->fast_iov) kfree(kmsg->iov); return -ENOMEM; } @@ -3159,6 +3163,11 @@ static int io_recvmsg_prep(struct io_kiocb *req, sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr)); sr->len = READ_ONCE(sqe->len); +#ifdef CONFIG_COMPAT + if (req->ctx->compat) + sr->msg_flags |= MSG_CMSG_COMPAT; +#endif + if (!io || req->opcode == IORING_OP_RECV) return 0; /* iovec is already imported */ @@ -3225,7 +3234,7 @@ static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt, if (req->io) return -EAGAIN; if (io_alloc_async_ctx(req)) { - if (kmsg && kmsg->iov != kmsg->fast_iov) + if (kmsg->iov != kmsg->fast_iov) kfree(kmsg->iov); return -ENOMEM; } @@ -3316,6 +3325,7 @@ static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr)); accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2)); accept->flags = READ_ONCE(sqe->accept_flags); + accept->nofile = rlimit(RLIMIT_NOFILE); return 0; #else return -EOPNOTSUPP; @@ -3332,7 +3342,8 @@ static int __io_accept(struct io_kiocb *req, struct io_kiocb **nxt, file_flags = force_nonblock ? O_NONBLOCK : 0; ret = __sys_accept4_file(req->file, file_flags, accept->addr, - accept->addr_len, accept->flags); + accept->addr_len, accept->flags, + accept->nofile); if (ret == -EAGAIN && force_nonblock) return -EAGAIN; if (ret == -ERESTARTSYS) @@ -4126,6 +4137,9 @@ static int io_req_defer_prep(struct io_kiocb *req, { ssize_t ret = 0; + if (!sqe) + return 0; + if (io_op_defs[req->opcode].file_table) { ret = io_grab_files(req); if (unlikely(ret)) @@ -4710,11 +4724,21 @@ static void __io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_kiocb *linked_timeout; struct io_kiocb *nxt = NULL; + const struct cred *old_creds = NULL; int ret; again: linked_timeout = io_prep_linked_timeout(req); + if (req->work.creds && req->work.creds != current_cred()) { + if (old_creds) + revert_creds(old_creds); + if (old_creds == req->work.creds) + old_creds = NULL; /* restored original creds */ + else + old_creds = override_creds(req->work.creds); + } + ret = io_issue_sqe(req, sqe, &nxt, true); /* @@ -4740,7 +4764,7 @@ punt: err: /* drop submission reference */ - io_put_req(req); + io_put_req_find_next(req, &nxt); if (linked_timeout) { if (!ret) @@ -4764,6 +4788,8 @@ done_req: goto punt; goto again; } + if (old_creds) + revert_creds(old_creds); } static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe) @@ -4808,7 +4834,6 @@ static inline void io_queue_link_head(struct io_kiocb *req) static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, struct io_submit_state *state, struct io_kiocb **link) { - const struct cred *old_creds = NULL; struct io_ring_ctx *ctx = req->ctx; unsigned int sqe_flags; int ret, id; @@ -4823,14 +4848,12 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, id = READ_ONCE(sqe->personality); if (id) { - const struct cred *personality_creds; - - personality_creds = idr_find(&ctx->personality_idr, id); - if (unlikely(!personality_creds)) { + req->work.creds = idr_find(&ctx->personality_idr, id); + if (unlikely(!req->work.creds)) { ret = -EINVAL; goto err_req; } - old_creds = override_creds(personality_creds); + get_cred(req->work.creds); } /* same numerical values with corresponding REQ_F_*, safe to copy */ @@ -4842,8 +4865,6 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, err_req: io_cqring_add_event(req, ret); io_double_put_req(req); - if (old_creds) - revert_creds(old_creds); return false; } @@ -4895,6 +4916,11 @@ err_req: if (sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) { req->flags |= REQ_F_LINK; INIT_LIST_HEAD(&req->link_list); + + if (io_alloc_async_ctx(req)) { + ret = -EAGAIN; + goto err_req; + } ret = io_req_defer_prep(req, sqe); if (ret) req->flags |= REQ_F_FAIL_LINK; @@ -4904,8 +4930,6 @@ err_req: } } - if (old_creds) - revert_creds(old_creds); return true; } @@ -5086,9 +5110,8 @@ static int io_sq_thread(void *data) const struct cred *old_cred; mm_segment_t old_fs; DEFINE_WAIT(wait); - unsigned inflight; unsigned long timeout; - int ret; + int ret = 0; complete(&ctx->completions[1]); @@ -5096,39 +5119,19 @@ static int io_sq_thread(void *data) set_fs(USER_DS); old_cred = override_creds(ctx->creds); - ret = timeout = inflight = 0; + timeout = jiffies + ctx->sq_thread_idle; while (!kthread_should_park()) { unsigned int to_submit; - if (inflight) { + if (!list_empty(&ctx->poll_list)) { unsigned nr_events = 0; - if (ctx->flags & IORING_SETUP_IOPOLL) { - /* - * inflight is the count of the maximum possible - * entries we submitted, but it can be smaller - * if we dropped some of them. If we don't have - * poll entries available, then we know that we - * have nothing left to poll for. Reset the - * inflight count to zero in that case. - */ - mutex_lock(&ctx->uring_lock); - if (!list_empty(&ctx->poll_list)) - __io_iopoll_check(ctx, &nr_events, 0); - else - inflight = 0; - mutex_unlock(&ctx->uring_lock); - } else { - /* - * Normal IO, just pretend everything completed. - * We don't have to poll completions for that. - */ - nr_events = inflight; - } - - inflight -= nr_events; - if (!inflight) + mutex_lock(&ctx->uring_lock); + if (!list_empty(&ctx->poll_list)) + io_iopoll_getevents(ctx, &nr_events, 0); + else timeout = jiffies + ctx->sq_thread_idle; + mutex_unlock(&ctx->uring_lock); } to_submit = io_sqring_entries(ctx); @@ -5139,34 +5142,47 @@ static int io_sq_thread(void *data) */ if (!to_submit || ret == -EBUSY) { /* + * Drop cur_mm before scheduling, we can't hold it for + * long periods (or over schedule()). Do this before + * adding ourselves to the waitqueue, as the unuse/drop + * may sleep. + */ + if (cur_mm) { + unuse_mm(cur_mm); + mmput(cur_mm); + cur_mm = NULL; + } + + /* * We're polling. If we're within the defined idle * period, then let us spin without work before going * to sleep. The exception is if we got EBUSY doing * more IO, we should wait for the application to * reap events and wake us up. */ - if (inflight || + if (!list_empty(&ctx->poll_list) || (!time_after(jiffies, timeout) && ret != -EBUSY && !percpu_ref_is_dying(&ctx->refs))) { cond_resched(); continue; } + prepare_to_wait(&ctx->sqo_wait, &wait, + TASK_INTERRUPTIBLE); + /* - * Drop cur_mm before scheduling, we can't hold it for - * long periods (or over schedule()). Do this before - * adding ourselves to the waitqueue, as the unuse/drop - * may sleep. + * While doing polled IO, before going to sleep, we need + * to check if there are new reqs added to poll_list, it + * is because reqs may have been punted to io worker and + * will be added to poll_list later, hence check the + * poll_list again. */ - if (cur_mm) { - unuse_mm(cur_mm); - mmput(cur_mm); - cur_mm = NULL; + if ((ctx->flags & IORING_SETUP_IOPOLL) && + !list_empty_careful(&ctx->poll_list)) { + finish_wait(&ctx->sqo_wait, &wait); + continue; } - prepare_to_wait(&ctx->sqo_wait, &wait, - TASK_INTERRUPTIBLE); - /* Tell userspace we may need a wakeup call */ ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP; /* make sure to read SQ tail after writing flags */ @@ -5194,8 +5210,7 @@ static int io_sq_thread(void *data) mutex_lock(&ctx->uring_lock); ret = io_submit_sqes(ctx, to_submit, NULL, -1, &cur_mm, true); mutex_unlock(&ctx->uring_lock); - if (ret > 0) - inflight += ret; + timeout = jiffies + ctx->sq_thread_idle; } set_fs(old_fs); @@ -5329,6 +5344,23 @@ static void io_file_ref_kill(struct percpu_ref *ref) complete(&data->done); } +static void io_file_ref_exit_and_free(struct work_struct *work) +{ + struct fixed_file_data *data; + + data = container_of(work, struct fixed_file_data, ref_work); + + /* + * Ensure any percpu-ref atomic switch callback has run, it could have + * been in progress when the files were being unregistered. Once + * that's done, we can safely exit and free the ref and containing + * data structure. + */ + rcu_barrier(); + percpu_ref_exit(&data->refs); + kfree(data); +} + static int io_sqe_files_unregister(struct io_ring_ctx *ctx) { struct fixed_file_data *data = ctx->file_data; @@ -5341,14 +5373,14 @@ static int io_sqe_files_unregister(struct io_ring_ctx *ctx) flush_work(&data->ref_work); wait_for_completion(&data->done); io_ring_file_ref_flush(data); - percpu_ref_exit(&data->refs); __io_sqe_files_unregister(ctx); nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE); for (i = 0; i < nr_tables; i++) kfree(data->table[i].files); kfree(data->table); - kfree(data); + INIT_WORK(&data->ref_work, io_file_ref_exit_and_free); + queue_work(system_wq, &data->ref_work); ctx->file_data = NULL; ctx->nr_user_files = 0; return 0; @@ -5600,7 +5632,6 @@ static void io_ring_file_ref_switch(struct work_struct *work) data = container_of(work, struct fixed_file_data, ref_work); io_ring_file_ref_flush(data); - percpu_ref_get(&data->refs); percpu_ref_switch_to_percpu(&data->refs); } @@ -5776,8 +5807,13 @@ static void io_atomic_switch(struct percpu_ref *ref) { struct fixed_file_data *data; + /* + * Juggle reference to ensure we hit zero, if needed, so we can + * switch back to percpu mode + */ data = container_of(ref, struct fixed_file_data, refs); - clear_bit(FFD_F_ATOMIC, &data->state); + percpu_ref_put(&data->refs); + percpu_ref_get(&data->refs); } static bool io_queue_file_removal(struct fixed_file_data *data, @@ -5800,11 +5836,7 @@ static bool io_queue_file_removal(struct fixed_file_data *data, llist_add(&pfile->llist, &data->put_llist); if (pfile == &pfile_stack) { - if (!test_and_set_bit(FFD_F_ATOMIC, &data->state)) { - percpu_ref_put(&data->refs); - percpu_ref_switch_to_atomic(&data->refs, - io_atomic_switch); - } + percpu_ref_switch_to_atomic(&data->refs, io_atomic_switch); wait_for_completion(&done); flush_work(&data->ref_work); return false; @@ -5878,10 +5910,8 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, up->offset++; } - if (ref_switch && !test_and_set_bit(FFD_F_ATOMIC, &data->state)) { - percpu_ref_put(&data->refs); + if (ref_switch) percpu_ref_switch_to_atomic(&data->refs, io_atomic_switch); - } return done ? done : err; } @@ -6339,6 +6369,7 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx) io_sqe_buffer_unregister(ctx); io_sqe_files_unregister(ctx); io_eventfd_unregister(ctx); + idr_destroy(&ctx->personality_idr); #if defined(CONFIG_UNIX) if (ctx->ring_sock) { @@ -6652,6 +6683,7 @@ out_fput: return submitted ? submitted : ret; } +#ifdef CONFIG_PROC_FS static int io_uring_show_cred(int id, void *p, void *data) { const struct cred *cred = p; @@ -6725,6 +6757,7 @@ static void io_uring_show_fdinfo(struct seq_file *m, struct file *f) percpu_ref_put(&ctx->refs); } } +#endif static const struct file_operations io_uring_fops = { .release = io_uring_release, @@ -6736,7 +6769,9 @@ static const struct file_operations io_uring_fops = { #endif .poll = io_uring_poll, .fasync = io_uring_fasync, +#ifdef CONFIG_PROC_FS .show_fdinfo = io_uring_show_fdinfo, +#endif }; static int io_allocate_scq_urings(struct io_ring_ctx *ctx, |