diff options
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 428 |
1 files changed, 255 insertions, 173 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 358f97be9c7b..5190bfb6a665 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -186,14 +186,23 @@ struct fixed_file_table { struct file **files; }; +struct fixed_file_ref_node { + struct percpu_ref refs; + struct list_head node; + struct list_head file_list; + struct fixed_file_data *file_data; + struct work_struct work; +}; + struct fixed_file_data { struct fixed_file_table *table; struct io_ring_ctx *ctx; + struct percpu_ref *cur_refs; struct percpu_ref refs; - struct llist_head put_llist; - struct work_struct ref_work; struct completion done; + struct list_head ref_list; + spinlock_t lock; }; struct io_buffer { @@ -317,6 +326,8 @@ struct io_ring_ctx { spinlock_t inflight_lock; struct list_head inflight_list; } ____cacheline_aligned_in_smp; + + struct work_struct exit_work; }; /* @@ -599,6 +610,7 @@ struct io_kiocb { }; struct io_async_ctx *io; + int cflags; bool needs_fixed_file; u8 opcode; @@ -606,10 +618,8 @@ struct io_kiocb { struct list_head list; unsigned int flags; refcount_t refs; - union { - struct task_struct *task; - unsigned long fsize; - }; + struct task_struct *task; + unsigned long fsize; u64 user_data; u32 result; u32 sequence; @@ -618,6 +628,8 @@ struct io_kiocb { struct list_head inflight_entry; + struct percpu_ref *fixed_file_refs; + union { /* * Only commands that never go async can use the below fields, @@ -629,7 +641,6 @@ struct io_kiocb { struct callback_head task_work; struct hlist_node hash_node; struct async_poll *apoll; - int cflags; }; struct io_wq_work work; }; @@ -848,7 +859,6 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, struct io_uring_files_update *ip, unsigned nr_args); static int io_grab_files(struct io_kiocb *req); -static void io_ring_file_ref_flush(struct fixed_file_data *data); static void io_cleanup_req(struct io_kiocb *req); static int io_file_get(struct io_submit_state *state, struct io_kiocb *req, int fd, struct file **out_file, bool fixed); @@ -1285,8 +1295,8 @@ static struct io_kiocb *io_get_fallback_req(struct io_ring_ctx *ctx) return NULL; } -static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx, - struct io_submit_state *state) +static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx, + struct io_submit_state *state) { gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; struct io_kiocb *req; @@ -1319,41 +1329,20 @@ static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx, req = state->reqs[state->free_reqs]; } -got_it: - req->io = NULL; - req->file = NULL; - req->ctx = ctx; - req->flags = 0; - /* one is dropped after submission, the other at completion */ - refcount_set(&req->refs, 2); - req->result = 0; - INIT_IO_WORK(&req->work, io_wq_submit_work); return req; fallback: - req = io_get_fallback_req(ctx); - if (req) - goto got_it; - percpu_ref_put(&ctx->refs); - return NULL; + return io_get_fallback_req(ctx); } static inline void io_put_file(struct io_kiocb *req, struct file *file, bool fixed) { if (fixed) - percpu_ref_put(&req->ctx->file_data->refs); + percpu_ref_put(req->fixed_file_refs); else fput(file); } -static void __io_req_do_free(struct io_kiocb *req) -{ - if (likely(!io_is_fallback_req(req))) - kmem_cache_free(req_cachep, req); - else - clear_bit_unlock(0, (unsigned long *) req->ctx->fallback_req); -} - static void __io_req_aux_free(struct io_kiocb *req) { if (req->flags & REQ_F_NEED_CLEANUP) @@ -1362,6 +1351,8 @@ static void __io_req_aux_free(struct io_kiocb *req) kfree(req->io); if (req->file) io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE)); + if (req->task) + put_task_struct(req->task); io_req_work_drop_env(req); } @@ -1382,7 +1373,10 @@ static void __io_free_req(struct io_kiocb *req) } percpu_ref_put(&req->ctx->refs); - __io_req_do_free(req); + if (likely(!io_is_fallback_req(req))) + kmem_cache_free(req_cachep, req); + else + clear_bit_unlock(0, (unsigned long *) req->ctx->fallback_req); } struct req_batch { @@ -1393,21 +1387,18 @@ struct req_batch { static void io_free_req_many(struct io_ring_ctx *ctx, struct req_batch *rb) { - int fixed_refs = rb->to_free; - if (!rb->to_free) return; if (rb->need_iter) { int i, inflight = 0; unsigned long flags; - fixed_refs = 0; for (i = 0; i < rb->to_free; i++) { struct io_kiocb *req = rb->reqs[i]; if (req->flags & REQ_F_FIXED_FILE) { req->file = NULL; - fixed_refs++; + percpu_ref_put(req->fixed_file_refs); } if (req->flags & REQ_F_INFLIGHT) inflight++; @@ -1433,8 +1424,6 @@ static void io_free_req_many(struct io_ring_ctx *ctx, struct req_batch *rb) } do_free: kmem_cache_free_bulk(req_cachep, rb->to_free, rb->reqs); - if (fixed_refs) - percpu_ref_put_many(&ctx->file_data->refs, fixed_refs); percpu_ref_put_many(&ctx->refs, rb->to_free); rb->to_free = rb->need_iter = 0; } @@ -1738,11 +1727,24 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, io_free_req_many(ctx, &rb); } +static void io_iopoll_queue(struct list_head *again) +{ + struct io_kiocb *req; + + do { + req = list_first_entry(again, struct io_kiocb, list); + list_del(&req->list); + refcount_inc(&req->refs); + io_queue_async_work(req); + } while (!list_empty(again)); +} + static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, long min) { struct io_kiocb *req, *tmp; LIST_HEAD(done); + LIST_HEAD(again); bool spin; int ret; @@ -1757,9 +1759,9 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, struct kiocb *kiocb = &req->rw.kiocb; /* - * Move completed entries to our local list. If we find a - * request that requires polling, break out and complete - * the done list first, if we have entries there. + * Move completed and retryable entries to our local lists. + * If we find a request that requires polling, break out + * and complete those lists first, if we have entries there. */ if (req->flags & REQ_F_IOPOLL_COMPLETED) { list_move_tail(&req->list, &done); @@ -1768,6 +1770,13 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, if (!list_empty(&done)) break; + if (req->result == -EAGAIN) { + list_move_tail(&req->list, &again); + continue; + } + if (!list_empty(&again)) + break; + ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin); if (ret < 0) break; @@ -1780,6 +1789,9 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, if (!list_empty(&done)) io_iopoll_complete(ctx, nr_events, &done); + if (!list_empty(&again)) + io_iopoll_queue(&again); + return ret; } @@ -2465,8 +2477,9 @@ static void io_req_map_rw(struct io_kiocb *req, ssize_t io_size, req->io->rw.iov = iovec; if (!req->io->rw.iov) { req->io->rw.iov = req->io->rw.fast_iov; - memcpy(req->io->rw.iov, fast_iov, - sizeof(struct iovec) * iter->nr_segs); + if (req->io->rw.iov != fast_iov) + memcpy(req->io->rw.iov, fast_iov, + sizeof(struct iovec) * iter->nr_segs); } else { req->flags |= REQ_F_NEED_CLEANUP; } @@ -2920,7 +2933,7 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (sqe->ioprio || sqe->buf_index) return -EINVAL; - if (sqe->flags & IOSQE_FIXED_FILE) + if (req->flags & REQ_F_FIXED_FILE) return -EBADF; if (req->flags & REQ_F_NEED_CLEANUP) return 0; @@ -2929,6 +2942,8 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) req->open.how.mode = READ_ONCE(sqe->len); fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); req->open.how.flags = READ_ONCE(sqe->open_flags); + if (force_o_largefile()) + req->open.how.flags |= O_LARGEFILE; req->open.filename = getname(fname); if (IS_ERR(req->open.filename)) { @@ -2951,7 +2966,7 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (sqe->ioprio || sqe->buf_index) return -EINVAL; - if (sqe->flags & IOSQE_FIXED_FILE) + if (req->flags & REQ_F_FIXED_FILE) return -EBADF; if (req->flags & REQ_F_NEED_CLEANUP) return 0; @@ -3305,7 +3320,7 @@ static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (sqe->ioprio || sqe->buf_index) return -EINVAL; - if (sqe->flags & IOSQE_FIXED_FILE) + if (req->flags & REQ_F_FIXED_FILE) return -EBADF; if (req->flags & REQ_F_NEED_CLEANUP) return 0; @@ -3382,7 +3397,7 @@ static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (sqe->ioprio || sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index) return -EINVAL; - if (sqe->flags & IOSQE_FIXED_FILE) + if (req->flags & REQ_F_FIXED_FILE) return -EBADF; req->close.fd = READ_ONCE(sqe->fd); @@ -3481,14 +3496,11 @@ static void __io_sync_file_range(struct io_kiocb *req) static void io_sync_file_range_finish(struct io_wq_work **workptr) { struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); - struct io_kiocb *nxt = NULL; if (io_req_cancelled(req)) return; __io_sync_file_range(req); io_put_req(req); /* put submission ref */ - if (nxt) - io_wq_assign_next(workptr, nxt); } static int io_sync_file_range(struct io_kiocb *req, bool force_nonblock) @@ -4114,6 +4126,7 @@ static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll, __poll_t mask, task_work_func_t func) { struct task_struct *tsk; + int ret; /* for instances that support it check for an event match first: */ if (mask && !(mask & poll->events)) @@ -4127,11 +4140,15 @@ static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll, req->result = mask; init_task_work(&req->task_work, func); /* - * If this fails, then the task is exiting. If that is the case, then - * the exit check will ultimately cancel these work items. Hence we - * don't need to check here and handle it specifically. + * If this fails, then the task is exiting. Punt to one of the io-wq + * threads to ensure the work gets run, we can't always rely on exit + * cancelation taking care of this. */ - task_work_add(tsk, &req->task_work, true); + ret = task_work_add(tsk, &req->task_work, true); + if (unlikely(ret)) { + tsk = io_wq_get_task(req->ctx->io_wq); + task_work_add(tsk, &req->task_work, true); + } wake_up_process(tsk); return 1; } @@ -4251,10 +4268,7 @@ static bool io_arm_poll_handler(struct io_kiocb *req) req->flags |= REQ_F_POLLED; memcpy(&apoll->work, &req->work, sizeof(req->work)); - /* - * Don't need a reference here, as we're adding it to the task - * task_works list. If the task exits, the list is pruned. - */ + get_task_struct(current); req->task = current; req->apoll = apoll; INIT_HLIST_NODE(&req->hash_node); @@ -4407,8 +4421,20 @@ static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error) static void io_poll_task_handler(struct io_kiocb *req, struct io_kiocb **nxt) { struct io_ring_ctx *ctx = req->ctx; + struct io_poll_iocb *poll = &req->poll; + + if (!req->result && !READ_ONCE(poll->canceled)) { + struct poll_table_struct pt = { ._key = poll->events }; + + req->result = vfs_poll(req->file, &pt) & poll->events; + } spin_lock_irq(&ctx->completion_lock); + if (!req->result && !READ_ONCE(poll->canceled)) { + add_wait_queue(poll->head, &poll->wait); + spin_unlock_irq(&ctx->completion_lock); + return; + } hash_del(&req->hash_node); io_poll_complete(req, req->result, 0); req->flags |= REQ_F_COMP_LOCKED; @@ -4465,10 +4491,7 @@ static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe events = READ_ONCE(sqe->poll_events); poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP; - /* - * Don't need a reference here, as we're adding it to the task - * task_works list. If the task exits, the list is pruned. - */ + get_task_struct(current); req->task = current; return 0; } @@ -5331,7 +5354,8 @@ static int io_file_get(struct io_submit_state *state, struct io_kiocb *req, file = io_file_from_index(ctx, fd); if (!file) return -EBADF; - percpu_ref_get(&ctx->file_data->refs); + req->fixed_file_refs = ctx->file_data->cur_refs; + percpu_ref_get(req->fixed_file_refs); } else { trace_io_uring_file_get(ctx, fd); file = __io_file_get(state, fd); @@ -5344,15 +5368,10 @@ static int io_file_get(struct io_submit_state *state, struct io_kiocb *req, } static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req, - const struct io_uring_sqe *sqe) + int fd, unsigned int flags) { - unsigned flags; - int fd; bool fixed; - flags = READ_ONCE(sqe->flags); - fd = READ_ONCE(sqe->fd); - if (!io_req_needs_file(req, fd)) return 0; @@ -5594,7 +5613,7 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, { struct io_ring_ctx *ctx = req->ctx; unsigned int sqe_flags; - int ret, id; + int ret, id, fd; sqe_flags = READ_ONCE(sqe->flags); @@ -5625,7 +5644,8 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, IOSQE_ASYNC | IOSQE_FIXED_FILE | IOSQE_BUFFER_SELECT); - ret = io_req_set_file(state, req, sqe); + fd = READ_ONCE(sqe->fd); + ret = io_req_set_file(state, req, fd, sqe_flags); if (unlikely(ret)) { err_req: io_cqring_add_event(req, ret); @@ -5741,8 +5761,7 @@ static void io_commit_sqring(struct io_ring_ctx *ctx) * used, it's important that those reads are done through READ_ONCE() to * prevent a re-load down the line. */ -static bool io_get_sqring(struct io_ring_ctx *ctx, struct io_kiocb *req, - const struct io_uring_sqe **sqe_ptr) +static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx) { u32 *sq_array = ctx->sq_array; unsigned head; @@ -5756,25 +5775,40 @@ static bool io_get_sqring(struct io_ring_ctx *ctx, struct io_kiocb *req, * though the application is the one updating it. */ head = READ_ONCE(sq_array[ctx->cached_sq_head & ctx->sq_mask]); - if (likely(head < ctx->sq_entries)) { - /* - * All io need record the previous position, if LINK vs DARIN, - * it can be used to mark the position of the first IO in the - * link list. - */ - req->sequence = ctx->cached_sq_head; - *sqe_ptr = &ctx->sq_sqes[head]; - req->opcode = READ_ONCE((*sqe_ptr)->opcode); - req->user_data = READ_ONCE((*sqe_ptr)->user_data); - ctx->cached_sq_head++; - return true; - } + if (likely(head < ctx->sq_entries)) + return &ctx->sq_sqes[head]; /* drop invalid entries */ - ctx->cached_sq_head++; ctx->cached_sq_dropped++; WRITE_ONCE(ctx->rings->sq_dropped, ctx->cached_sq_dropped); - return false; + return NULL; +} + +static inline void io_consume_sqe(struct io_ring_ctx *ctx) +{ + ctx->cached_sq_head++; +} + +static void io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, + const struct io_uring_sqe *sqe) +{ + /* + * All io need record the previous position, if LINK vs DARIN, + * it can be used to mark the position of the first IO in the + * link list. + */ + req->sequence = ctx->cached_sq_head; + req->opcode = READ_ONCE(sqe->opcode); + req->user_data = READ_ONCE(sqe->user_data); + req->io = NULL; + req->file = NULL; + req->ctx = ctx; + req->flags = 0; + /* one is dropped after submission, the other at completion */ + refcount_set(&req->refs, 2); + req->task = NULL; + req->result = 0; + INIT_IO_WORK(&req->work, io_wq_submit_work); } static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, @@ -5812,17 +5846,20 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, struct io_kiocb *req; int err; - req = io_get_req(ctx, statep); + sqe = io_get_sqe(ctx); + if (unlikely(!sqe)) { + io_consume_sqe(ctx); + break; + } + req = io_alloc_req(ctx, statep); if (unlikely(!req)) { if (!submitted) submitted = -EAGAIN; break; } - if (!io_get_sqring(ctx, req, &sqe)) { - __io_req_do_free(req); - break; - } + io_init_req(ctx, req, sqe); + io_consume_sqe(ctx); /* will complete beyond this point, count as submitted */ submitted++; @@ -5962,6 +5999,7 @@ static int io_sq_thread(void *data) } if (current->task_works) { task_work_run(); + finish_wait(&ctx->sqo_wait, &wait); continue; } if (signal_pending(current)) @@ -6124,43 +6162,36 @@ 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; + struct fixed_file_ref_node *ref_node = NULL; unsigned nr_tables, i; + unsigned long flags; if (!data) return -ENXIO; - percpu_ref_kill_and_confirm(&data->refs, io_file_ref_kill); - flush_work(&data->ref_work); + spin_lock_irqsave(&data->lock, flags); + if (!list_empty(&data->ref_list)) + ref_node = list_first_entry(&data->ref_list, + struct fixed_file_ref_node, node); + spin_unlock_irqrestore(&data->lock, flags); + if (ref_node) + percpu_ref_kill(&ref_node->refs); + + percpu_ref_kill(&data->refs); + + /* wait for all refs nodes to complete */ wait_for_completion(&data->done); - io_ring_file_ref_flush(data); __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); - INIT_WORK(&data->ref_work, io_file_ref_exit_and_free); - queue_work(system_wq, &data->ref_work); + percpu_ref_exit(&data->refs); + kfree(data); ctx->file_data = NULL; ctx->nr_user_files = 0; return 0; @@ -6204,13 +6235,6 @@ static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset) struct sk_buff *skb; int i, nr_files; - if (!capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) { - unsigned long inflight = ctx->user->unix_inflight + nr; - - if (inflight > task_rlimit(current, RLIMIT_NOFILE)) - return -EMFILE; - } - fpl = kzalloc(sizeof(*fpl), GFP_KERNEL); if (!fpl) return -ENOMEM; @@ -6385,46 +6409,72 @@ static void io_ring_file_put(struct io_ring_ctx *ctx, struct file *file) } struct io_file_put { - struct llist_node llist; + struct list_head list; struct file *file; }; -static void io_ring_file_ref_flush(struct fixed_file_data *data) +static void io_file_put_work(struct work_struct *work) { + struct fixed_file_ref_node *ref_node; + struct fixed_file_data *file_data; + struct io_ring_ctx *ctx; struct io_file_put *pfile, *tmp; - struct llist_node *node; + unsigned long flags; - while ((node = llist_del_all(&data->put_llist)) != NULL) { - llist_for_each_entry_safe(pfile, tmp, node, llist) { - io_ring_file_put(data->ctx, pfile->file); - kfree(pfile); - } + ref_node = container_of(work, struct fixed_file_ref_node, work); + file_data = ref_node->file_data; + ctx = file_data->ctx; + + list_for_each_entry_safe(pfile, tmp, &ref_node->file_list, list) { + list_del_init(&pfile->list); + io_ring_file_put(ctx, pfile->file); + kfree(pfile); } + + spin_lock_irqsave(&file_data->lock, flags); + list_del_init(&ref_node->node); + spin_unlock_irqrestore(&file_data->lock, flags); + + percpu_ref_exit(&ref_node->refs); + kfree(ref_node); + percpu_ref_put(&file_data->refs); } -static void io_ring_file_ref_switch(struct work_struct *work) +static void io_file_data_ref_zero(struct percpu_ref *ref) { - struct fixed_file_data *data; + struct fixed_file_ref_node *ref_node; + + ref_node = container_of(ref, struct fixed_file_ref_node, refs); - data = container_of(work, struct fixed_file_data, ref_work); - io_ring_file_ref_flush(data); - percpu_ref_switch_to_percpu(&data->refs); + queue_work(system_wq, &ref_node->work); } -static void io_file_data_ref_zero(struct percpu_ref *ref) +static struct fixed_file_ref_node *alloc_fixed_file_ref_node( + struct io_ring_ctx *ctx) { - struct fixed_file_data *data; + struct fixed_file_ref_node *ref_node; - data = container_of(ref, struct fixed_file_data, refs); + ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); + if (!ref_node) + return ERR_PTR(-ENOMEM); + + if (percpu_ref_init(&ref_node->refs, io_file_data_ref_zero, + 0, GFP_KERNEL)) { + kfree(ref_node); + return ERR_PTR(-ENOMEM); + } + INIT_LIST_HEAD(&ref_node->node); + INIT_LIST_HEAD(&ref_node->file_list); + INIT_WORK(&ref_node->work, io_file_put_work); + ref_node->file_data = ctx->file_data; + return ref_node; - /* - * We can't safely switch from inside this context, punt to wq. If - * the table ref is going away, the table is being unregistered. - * Don't queue up the async work for that case, the caller will - * handle it. - */ - if (!percpu_ref_is_dying(&data->refs)) - queue_work(system_wq, &data->ref_work); +} + +static void destroy_fixed_file_ref_node(struct fixed_file_ref_node *ref_node) +{ + percpu_ref_exit(&ref_node->refs); + kfree(ref_node); } static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, @@ -6435,6 +6485,8 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, struct file *file; int fd, ret = 0; unsigned i; + struct fixed_file_ref_node *ref_node; + unsigned long flags; if (ctx->file_data) return -EBUSY; @@ -6448,6 +6500,8 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, return -ENOMEM; ctx->file_data->ctx = ctx; init_completion(&ctx->file_data->done); + INIT_LIST_HEAD(&ctx->file_data->ref_list); + spin_lock_init(&ctx->file_data->lock); nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE); ctx->file_data->table = kcalloc(nr_tables, @@ -6459,15 +6513,13 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, return -ENOMEM; } - if (percpu_ref_init(&ctx->file_data->refs, io_file_data_ref_zero, + if (percpu_ref_init(&ctx->file_data->refs, io_file_ref_kill, PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) { kfree(ctx->file_data->table); kfree(ctx->file_data); ctx->file_data = NULL; return -ENOMEM; } - ctx->file_data->put_llist.first = NULL; - INIT_WORK(&ctx->file_data->ref_work, io_ring_file_ref_switch); if (io_sqe_alloc_file_tables(ctx, nr_tables, nr_args)) { percpu_ref_exit(&ctx->file_data->refs); @@ -6530,9 +6582,22 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, } ret = io_sqe_files_scm(ctx); - if (ret) + if (ret) { io_sqe_files_unregister(ctx); + return ret; + } + + ref_node = alloc_fixed_file_ref_node(ctx); + if (IS_ERR(ref_node)) { + io_sqe_files_unregister(ctx); + return PTR_ERR(ref_node); + } + ctx->file_data->cur_refs = &ref_node->refs; + spin_lock_irqsave(&ctx->file_data->lock, flags); + list_add(&ref_node->node, &ctx->file_data->ref_list); + spin_unlock_irqrestore(&ctx->file_data->lock, flags); + percpu_ref_get(&ctx->file_data->refs); return ret; } @@ -6579,30 +6644,21 @@ static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file, #endif } -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); - percpu_ref_put(&data->refs); - percpu_ref_get(&data->refs); -} - static int io_queue_file_removal(struct fixed_file_data *data, - struct file *file) + struct file *file) { struct io_file_put *pfile; + struct percpu_ref *refs = data->cur_refs; + struct fixed_file_ref_node *ref_node; pfile = kzalloc(sizeof(*pfile), GFP_KERNEL); if (!pfile) return -ENOMEM; + ref_node = container_of(refs, struct fixed_file_ref_node, refs); pfile->file = file; - llist_add(&pfile->llist, &data->put_llist); + list_add(&pfile->list, &ref_node->file_list); + return 0; } @@ -6611,17 +6667,23 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, unsigned nr_args) { struct fixed_file_data *data = ctx->file_data; - bool ref_switch = false; + struct fixed_file_ref_node *ref_node; struct file *file; __s32 __user *fds; int fd, i, err; __u32 done; + unsigned long flags; + bool needs_switch = false; if (check_add_overflow(up->offset, nr_args, &done)) return -EOVERFLOW; if (done > ctx->nr_user_files) return -EINVAL; + ref_node = alloc_fixed_file_ref_node(ctx); + if (IS_ERR(ref_node)) + return PTR_ERR(ref_node); + done = 0; fds = u64_to_user_ptr(up->fds); while (nr_args) { @@ -6642,7 +6704,7 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, if (err) break; table->files[index] = NULL; - ref_switch = true; + needs_switch = true; } if (fd != -1) { file = fget(fd); @@ -6673,11 +6735,19 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, up->offset++; } - if (ref_switch) - percpu_ref_switch_to_atomic(&data->refs, io_atomic_switch); + if (needs_switch) { + percpu_ref_kill(data->cur_refs); + spin_lock_irqsave(&data->lock, flags); + list_add(&ref_node->node, &data->ref_list); + data->cur_refs = &ref_node->refs; + spin_unlock_irqrestore(&data->lock, flags); + percpu_ref_get(&ctx->file_data->refs); + } else + destroy_fixed_file_ref_node(ref_node); return done ? done : err; } + static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args) { @@ -7203,6 +7273,18 @@ static int io_remove_personalities(int id, void *p, void *data) return 0; } +static void io_ring_exit_work(struct work_struct *work) +{ + struct io_ring_ctx *ctx; + + ctx = container_of(work, struct io_ring_ctx, exit_work); + if (ctx->rings) + io_cqring_overflow_flush(ctx, true); + + wait_for_completion(&ctx->completions[0]); + io_ring_ctx_free(ctx); +} + static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) { mutex_lock(&ctx->uring_lock); @@ -7230,8 +7312,8 @@ static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) if (ctx->rings) io_cqring_overflow_flush(ctx, true); idr_for_each(&ctx->personality_idr, io_remove_personalities, ctx); - wait_for_completion(&ctx->completions[0]); - io_ring_ctx_free(ctx); + INIT_WORK(&ctx->exit_work, io_ring_exit_work); + queue_work(system_wq, &ctx->exit_work); } static int io_uring_release(struct inode *inode, struct file *file) |