diff options
Diffstat (limited to 'drivers/block/ublk_drv.c')
-rw-r--r-- | drivers/block/ublk_drv.c | 711 |
1 files changed, 498 insertions, 213 deletions
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index f9032076bc06..9fd284fa76dc 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -50,6 +50,8 @@ /* private ioctl command mirror */ #define UBLK_CMD_DEL_DEV_ASYNC _IOC_NR(UBLK_U_CMD_DEL_DEV_ASYNC) +#define UBLK_CMD_UPDATE_SIZE _IOC_NR(UBLK_U_CMD_UPDATE_SIZE) +#define UBLK_CMD_QUIESCE_DEV _IOC_NR(UBLK_U_CMD_QUIESCE_DEV) #define UBLK_IO_REGISTER_IO_BUF _IOC_NR(UBLK_U_IO_REGISTER_IO_BUF) #define UBLK_IO_UNREGISTER_IO_BUF _IOC_NR(UBLK_U_IO_UNREGISTER_IO_BUF) @@ -64,7 +66,11 @@ | UBLK_F_CMD_IOCTL_ENCODE \ | UBLK_F_USER_COPY \ | UBLK_F_ZONED \ - | UBLK_F_USER_RECOVERY_FAIL_IO) + | UBLK_F_USER_RECOVERY_FAIL_IO \ + | UBLK_F_UPDATE_SIZE \ + | UBLK_F_AUTO_BUF_REG \ + | UBLK_F_QUIESCE \ + | UBLK_F_PER_IO_DAEMON) #define UBLK_F_ALL_RECOVERY_FLAGS (UBLK_F_USER_RECOVERY \ | UBLK_F_USER_RECOVERY_REISSUE \ @@ -77,7 +83,11 @@ UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT) struct ublk_rq_data { - struct kref ref; + refcount_t ref; + + /* for auto-unregister buffer in case of UBLK_F_AUTO_BUF_REG */ + u16 buf_index; + void *buf_ctx_handle; }; struct ublk_uring_cmd_pdu { @@ -99,6 +109,9 @@ struct ublk_uring_cmd_pdu { * setup in ublk uring_cmd handler */ struct ublk_queue *ubq; + + struct ublk_auto_buf_reg buf; + u16 tag; }; @@ -131,6 +144,14 @@ struct ublk_uring_cmd_pdu { */ #define UBLK_IO_FLAG_NEED_GET_DATA 0x08 +/* + * request buffer is registered automatically, so we have to unregister it + * before completing this request. + * + * io_uring will unregister buffer automatically for us during exiting. + */ +#define UBLK_IO_FLAG_AUTO_BUF_REG 0x10 + /* atomic RW with ubq->cancel_lock */ #define UBLK_IO_FLAG_CANCELED 0x80000000 @@ -140,7 +161,14 @@ struct ublk_io { unsigned int flags; int res; - struct io_uring_cmd *cmd; + union { + /* valid if UBLK_IO_FLAG_ACTIVE is set */ + struct io_uring_cmd *cmd; + /* valid if UBLK_IO_FLAG_OWNED_BY_SRV is set */ + struct request *req; + }; + + struct task_struct *task; }; struct ublk_queue { @@ -148,11 +176,9 @@ struct ublk_queue { int q_depth; unsigned long flags; - struct task_struct *ubq_daemon; struct ublksrv_io_desc *io_cmd_buf; bool force_abort; - bool timeout; bool canceling; bool fail_io; /* copy of dev->state == UBLK_S_DEV_FAIL_IO */ unsigned short nr_io_ready; /* how many ios setup */ @@ -198,13 +224,19 @@ struct ublk_params_header { __u32 types; }; +static void ublk_io_release(void *priv); static void ublk_stop_dev_unlocked(struct ublk_device *ub); static void ublk_abort_queue(struct ublk_device *ub, struct ublk_queue *ubq); static inline struct request *__ublk_check_and_get_req(struct ublk_device *ub, const struct ublk_queue *ubq, int tag, size_t offset); static inline unsigned int ublk_req_build_flags(struct request *req); -static inline struct ublksrv_io_desc *ublk_get_iod(struct ublk_queue *ubq, - int tag); + +static inline struct ublksrv_io_desc * +ublk_get_iod(const struct ublk_queue *ubq, unsigned tag) +{ + return &ubq->io_cmd_buf[tag]; +} + static inline bool ublk_dev_is_zoned(const struct ublk_device *ub) { return ub->dev_info.flags & UBLK_F_ZONED; @@ -356,8 +388,7 @@ static int ublk_report_zones(struct gendisk *disk, sector_t sector, if (ret) goto free_req; - ret = blk_rq_map_kern(disk->queue, req, buffer, buffer_length, - GFP_KERNEL); + ret = blk_rq_map_kern(req, buffer, buffer_length, GFP_KERNEL); if (ret) goto erase_desc; @@ -477,7 +508,6 @@ static blk_status_t ublk_setup_iod_zoned(struct ublk_queue *ubq, #endif static inline void __ublk_complete_rq(struct request *req); -static void ublk_complete_rq(struct kref *ref); static dev_t ublk_chr_devt; static const struct class ublk_chr_class = { @@ -609,6 +639,11 @@ static inline bool ublk_support_zero_copy(const struct ublk_queue *ubq) return ubq->flags & UBLK_F_SUPPORT_ZERO_COPY; } +static inline bool ublk_support_auto_buf_reg(const struct ublk_queue *ubq) +{ + return ubq->flags & UBLK_F_AUTO_BUF_REG; +} + static inline bool ublk_support_user_copy(const struct ublk_queue *ubq) { return ubq->flags & UBLK_F_USER_COPY; @@ -616,7 +651,8 @@ static inline bool ublk_support_user_copy(const struct ublk_queue *ubq) static inline bool ublk_need_map_io(const struct ublk_queue *ubq) { - return !ublk_support_user_copy(ubq) && !ublk_support_zero_copy(ubq); + return !ublk_support_user_copy(ubq) && !ublk_support_zero_copy(ubq) && + !ublk_support_auto_buf_reg(ubq); } static inline bool ublk_need_req_ref(const struct ublk_queue *ubq) @@ -627,8 +663,13 @@ static inline bool ublk_need_req_ref(const struct ublk_queue *ubq) * * for zero copy, request buffer need to be registered to io_uring * buffer table, so reference is needed + * + * For auto buffer register, ublk server still may issue + * UBLK_IO_COMMIT_AND_FETCH_REQ before one registered buffer is used up, + * so reference is required too. */ - return ublk_support_user_copy(ubq) || ublk_support_zero_copy(ubq); + return ublk_support_user_copy(ubq) || ublk_support_zero_copy(ubq) || + ublk_support_auto_buf_reg(ubq); } static inline void ublk_init_req_ref(const struct ublk_queue *ubq, @@ -637,7 +678,7 @@ static inline void ublk_init_req_ref(const struct ublk_queue *ubq, if (ublk_need_req_ref(ubq)) { struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); - kref_init(&data->ref); + refcount_set(&data->ref, 1); } } @@ -647,7 +688,7 @@ static inline bool ublk_get_req_ref(const struct ublk_queue *ubq, if (ublk_need_req_ref(ubq)) { struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); - return kref_get_unless_zero(&data->ref); + return refcount_inc_not_zero(&data->ref); } return true; @@ -659,7 +700,8 @@ static inline void ublk_put_req_ref(const struct ublk_queue *ubq, if (ublk_need_req_ref(ubq)) { struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); - kref_put(&data->ref, ublk_complete_rq); + if (refcount_dec_and_test(&data->ref)) + __ublk_complete_rq(req); } else { __ublk_complete_rq(req); } @@ -695,12 +737,6 @@ static inline bool ublk_rq_has_data(const struct request *rq) return bio_has_data(rq->bio); } -static inline struct ublksrv_io_desc *ublk_get_iod(struct ublk_queue *ubq, - int tag) -{ - return &ubq->io_cmd_buf[tag]; -} - static inline struct ublksrv_io_desc * ublk_queue_cmd_buf(struct ublk_device *ub, int q_id) { @@ -1064,11 +1100,6 @@ static inline struct ublk_uring_cmd_pdu *ublk_get_uring_cmd_pdu( return io_uring_cmd_to_pdu(ioucmd, struct ublk_uring_cmd_pdu); } -static inline bool ubq_daemon_is_dying(struct ublk_queue *ubq) -{ - return !ubq->ubq_daemon || ubq->ubq_daemon->flags & PF_EXITING; -} - /* todo: handle partial completion */ static inline void __ublk_complete_rq(struct request *req) { @@ -1117,18 +1148,12 @@ exit: blk_mq_end_request(req, res); } -static void ublk_complete_rq(struct kref *ref) +static struct io_uring_cmd *__ublk_prep_compl_io_cmd(struct ublk_io *io, + struct request *req) { - struct ublk_rq_data *data = container_of(ref, struct ublk_rq_data, - ref); - struct request *req = blk_mq_rq_from_pdu(data); + /* read cmd first because req will overwrite it */ + struct io_uring_cmd *cmd = io->cmd; - __ublk_complete_rq(req); -} - -static void ubq_complete_io_cmd(struct ublk_io *io, int res, - unsigned issue_flags) -{ /* mark this cmd owned by ublksrv */ io->flags |= UBLK_IO_FLAG_OWNED_BY_SRV; @@ -1138,8 +1163,17 @@ static void ubq_complete_io_cmd(struct ublk_io *io, int res, */ io->flags &= ~UBLK_IO_FLAG_ACTIVE; + io->req = req; + return cmd; +} + +static void ublk_complete_io_cmd(struct ublk_io *io, struct request *req, + int res, unsigned issue_flags) +{ + struct io_uring_cmd *cmd = __ublk_prep_compl_io_cmd(io, req); + /* tell ublksrv one io request is coming */ - io_uring_cmd_done(io->cmd, res, 0, issue_flags); + io_uring_cmd_done(cmd, res, 0, issue_flags); } #define UBLK_REQUEUE_DELAY_MS 3 @@ -1154,28 +1188,103 @@ static inline void __ublk_abort_rq(struct ublk_queue *ubq, blk_mq_end_request(rq, BLK_STS_IOERR); } +static void ublk_auto_buf_reg_fallback(struct request *req) +{ + const struct ublk_queue *ubq = req->mq_hctx->driver_data; + struct ublksrv_io_desc *iod = ublk_get_iod(ubq, req->tag); + struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); + + iod->op_flags |= UBLK_IO_F_NEED_REG_BUF; + refcount_set(&data->ref, 1); +} + +static bool ublk_auto_buf_reg(struct request *req, struct ublk_io *io, + unsigned int issue_flags) +{ + struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(io->cmd); + struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); + int ret; + + ret = io_buffer_register_bvec(io->cmd, req, ublk_io_release, + pdu->buf.index, issue_flags); + if (ret) { + if (pdu->buf.flags & UBLK_AUTO_BUF_REG_FALLBACK) { + ublk_auto_buf_reg_fallback(req); + return true; + } + blk_mq_end_request(req, BLK_STS_IOERR); + return false; + } + /* one extra reference is dropped by ublk_io_release */ + refcount_set(&data->ref, 2); + + data->buf_ctx_handle = io_uring_cmd_ctx_handle(io->cmd); + /* store buffer index in request payload */ + data->buf_index = pdu->buf.index; + io->flags |= UBLK_IO_FLAG_AUTO_BUF_REG; + return true; +} + +static bool ublk_prep_auto_buf_reg(struct ublk_queue *ubq, + struct request *req, struct ublk_io *io, + unsigned int issue_flags) +{ + if (ublk_support_auto_buf_reg(ubq) && ublk_rq_has_data(req)) + return ublk_auto_buf_reg(req, io, issue_flags); + + ublk_init_req_ref(ubq, req); + return true; +} + +static bool ublk_start_io(const struct ublk_queue *ubq, struct request *req, + struct ublk_io *io) +{ + unsigned mapped_bytes = ublk_map_io(ubq, req, io); + + /* partially mapped, update io descriptor */ + if (unlikely(mapped_bytes != blk_rq_bytes(req))) { + /* + * Nothing mapped, retry until we succeed. + * + * We may never succeed in mapping any bytes here because + * of OOM. TODO: reserve one buffer with single page pinned + * for providing forward progress guarantee. + */ + if (unlikely(!mapped_bytes)) { + blk_mq_requeue_request(req, false); + blk_mq_delay_kick_requeue_list(req->q, + UBLK_REQUEUE_DELAY_MS); + return false; + } + + ublk_get_iod(ubq, req->tag)->nr_sectors = + mapped_bytes >> 9; + } + + return true; +} + static void ublk_dispatch_req(struct ublk_queue *ubq, struct request *req, unsigned int issue_flags) { int tag = req->tag; struct ublk_io *io = &ubq->ios[tag]; - unsigned int mapped_bytes; - pr_devel("%s: complete: op %d, qid %d tag %d io_flags %x addr %llx\n", - __func__, io->cmd->cmd_op, ubq->q_id, req->tag, io->flags, + pr_devel("%s: complete: qid %d tag %d io_flags %x addr %llx\n", + __func__, ubq->q_id, req->tag, io->flags, ublk_get_iod(ubq, req->tag)->addr); /* * Task is exiting if either: * - * (1) current != ubq_daemon. + * (1) current != io->task. * io_uring_cmd_complete_in_task() tries to run task_work - * in a workqueue if ubq_daemon(cmd's task) is PF_EXITING. + * in a workqueue if cmd's task is PF_EXITING. * * (2) current->flags & PF_EXITING. */ - if (unlikely(current != ubq->ubq_daemon || current->flags & PF_EXITING)) { + if (unlikely(current != io->task || current->flags & PF_EXITING)) { __ublk_abort_rq(ubq, req); return; } @@ -1183,54 +1292,22 @@ static void ublk_dispatch_req(struct ublk_queue *ubq, if (ublk_need_get_data(ubq) && ublk_need_map_req(req)) { /* * We have not handled UBLK_IO_NEED_GET_DATA command yet, - * so immepdately pass UBLK_IO_RES_NEED_GET_DATA to ublksrv + * so immediately pass UBLK_IO_RES_NEED_GET_DATA to ublksrv * and notify it. */ - if (!(io->flags & UBLK_IO_FLAG_NEED_GET_DATA)) { - io->flags |= UBLK_IO_FLAG_NEED_GET_DATA; - pr_devel("%s: need get data. op %d, qid %d tag %d io_flags %x\n", - __func__, io->cmd->cmd_op, ubq->q_id, - req->tag, io->flags); - ubq_complete_io_cmd(io, UBLK_IO_RES_NEED_GET_DATA, issue_flags); - return; - } - /* - * We have handled UBLK_IO_NEED_GET_DATA command, - * so clear UBLK_IO_FLAG_NEED_GET_DATA now and just - * do the copy work. - */ - io->flags &= ~UBLK_IO_FLAG_NEED_GET_DATA; - /* update iod->addr because ublksrv may have passed a new io buffer */ - ublk_get_iod(ubq, req->tag)->addr = io->addr; - pr_devel("%s: update iod->addr: op %d, qid %d tag %d io_flags %x addr %llx\n", - __func__, io->cmd->cmd_op, ubq->q_id, req->tag, io->flags, - ublk_get_iod(ubq, req->tag)->addr); + io->flags |= UBLK_IO_FLAG_NEED_GET_DATA; + pr_devel("%s: need get data. qid %d tag %d io_flags %x\n", + __func__, ubq->q_id, req->tag, io->flags); + ublk_complete_io_cmd(io, req, UBLK_IO_RES_NEED_GET_DATA, + issue_flags); + return; } - mapped_bytes = ublk_map_io(ubq, req, io); - - /* partially mapped, update io descriptor */ - if (unlikely(mapped_bytes != blk_rq_bytes(req))) { - /* - * Nothing mapped, retry until we succeed. - * - * We may never succeed in mapping any bytes here because - * of OOM. TODO: reserve one buffer with single page pinned - * for providing forward progress guarantee. - */ - if (unlikely(!mapped_bytes)) { - blk_mq_requeue_request(req, false); - blk_mq_delay_kick_requeue_list(req->q, - UBLK_REQUEUE_DELAY_MS); - return; - } - - ublk_get_iod(ubq, req->tag)->nr_sectors = - mapped_bytes >> 9; - } + if (!ublk_start_io(ubq, req, io)) + return; - ublk_init_req_ref(ubq, req); - ubq_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags); + if (ublk_prep_auto_buf_reg(ubq, req, io, issue_flags)) + ublk_complete_io_cmd(io, req, UBLK_IO_RES_OK, issue_flags); } static void ublk_cmd_tw_cb(struct io_uring_cmd *cmd, @@ -1256,24 +1333,22 @@ static void ublk_cmd_list_tw_cb(struct io_uring_cmd *cmd, { struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); struct request *rq = pdu->req_list; - struct ublk_queue *ubq = pdu->ubq; struct request *next; do { next = rq->rq_next; rq->rq_next = NULL; - ublk_dispatch_req(ubq, rq, issue_flags); + ublk_dispatch_req(rq->mq_hctx->driver_data, rq, issue_flags); rq = next; } while (rq); } -static void ublk_queue_cmd_list(struct ublk_queue *ubq, struct rq_list *l) +static void ublk_queue_cmd_list(struct ublk_io *io, struct rq_list *l) { - struct request *rq = rq_list_peek(l); - struct io_uring_cmd *cmd = ubq->ios[rq->tag].cmd; + struct io_uring_cmd *cmd = io->cmd; struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); - pdu->req_list = rq; + pdu->req_list = rq_list_peek(l); rq_list_init(l); io_uring_cmd_complete_in_task(cmd, ublk_cmd_list_tw_cb); } @@ -1281,13 +1356,10 @@ static void ublk_queue_cmd_list(struct ublk_queue *ubq, struct rq_list *l) static enum blk_eh_timer_return ublk_timeout(struct request *rq) { struct ublk_queue *ubq = rq->mq_hctx->driver_data; + struct ublk_io *io = &ubq->ios[rq->tag]; if (ubq->flags & UBLK_F_UNPRIVILEGED_DEV) { - if (!ubq->timeout) { - send_sig(SIGKILL, ubq->ubq_daemon, 0); - ubq->timeout = true; - } - + send_sig(SIGKILL, io->task, 0); return BLK_EH_DONE; } @@ -1351,28 +1423,39 @@ static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx, return BLK_STS_OK; } +static inline bool ublk_belong_to_same_batch(const struct ublk_io *io, + const struct ublk_io *io2) +{ + return (io_uring_cmd_ctx_handle(io->cmd) == + io_uring_cmd_ctx_handle(io2->cmd)) && + (io->task == io2->task); +} + static void ublk_queue_rqs(struct rq_list *rqlist) { struct rq_list requeue_list = { }; struct rq_list submit_list = { }; - struct ublk_queue *ubq = NULL; + struct ublk_io *io = NULL; struct request *req; while ((req = rq_list_pop(rqlist))) { struct ublk_queue *this_q = req->mq_hctx->driver_data; + struct ublk_io *this_io = &this_q->ios[req->tag]; - if (ubq && ubq != this_q && !rq_list_empty(&submit_list)) - ublk_queue_cmd_list(ubq, &submit_list); - ubq = this_q; - - if (ublk_prep_req(ubq, req, true) == BLK_STS_OK) - rq_list_add_tail(&submit_list, req); - else + if (ublk_prep_req(this_q, req, true) != BLK_STS_OK) { rq_list_add_tail(&requeue_list, req); + continue; + } + + if (io && !ublk_belong_to_same_batch(io, this_io) && + !rq_list_empty(&submit_list)) + ublk_queue_cmd_list(io, &submit_list); + io = this_io; + rq_list_add_tail(&submit_list, req); } - if (ubq && !rq_list_empty(&submit_list)) - ublk_queue_cmd_list(ubq, &submit_list); + if (!rq_list_empty(&submit_list)) + ublk_queue_cmd_list(io, &submit_list); *rqlist = requeue_list; } @@ -1400,17 +1483,6 @@ static void ublk_queue_reinit(struct ublk_device *ub, struct ublk_queue *ubq) /* All old ioucmds have to be completed */ ubq->nr_io_ready = 0; - /* - * old daemon is PF_EXITING, put it now - * - * It could be NULL in case of closing one quisced device. - */ - if (ubq->ubq_daemon) - put_task_struct(ubq->ubq_daemon); - /* We have to reset it to NULL, otherwise ub won't accept new FETCH_REQ */ - ubq->ubq_daemon = NULL; - ubq->timeout = false; - for (i = 0; i < ubq->q_depth; i++) { struct ublk_io *io = &ubq->ios[i]; @@ -1421,6 +1493,17 @@ static void ublk_queue_reinit(struct ublk_device *ub, struct ublk_queue *ubq) io->flags &= UBLK_IO_FLAG_CANCELED; io->cmd = NULL; io->addr = 0; + + /* + * old task is PF_EXITING, put it now + * + * It could be NULL in case of closing one quiesced + * device. + */ + if (io->task) { + put_task_struct(io->task); + io->task = NULL; + } } } @@ -1442,7 +1525,7 @@ static void ublk_reset_ch_dev(struct ublk_device *ub) for (i = 0; i < ub->dev_info.nr_hw_queues; i++) ublk_queue_reinit(ub, ublk_get_queue(ub, i)); - /* set to NULL, otherwise new ubq_daemon cannot mmap the io_cmd_buf */ + /* set to NULL, otherwise new tasks cannot mmap io_cmd_buf */ ub->mm = NULL; ub->nr_queues_ready = 0; ub->nr_privileged_daemon = 0; @@ -1590,30 +1673,6 @@ static int ublk_ch_mmap(struct file *filp, struct vm_area_struct *vma) return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot); } -static void ublk_commit_completion(struct ublk_device *ub, - const struct ublksrv_io_cmd *ub_cmd) -{ - u32 qid = ub_cmd->q_id, tag = ub_cmd->tag; - struct ublk_queue *ubq = ublk_get_queue(ub, qid); - struct ublk_io *io = &ubq->ios[tag]; - struct request *req; - - /* now this cmd slot is owned by nbd driver */ - io->flags &= ~UBLK_IO_FLAG_OWNED_BY_SRV; - io->res = ub_cmd->result; - - /* find the io request and complete */ - req = blk_mq_tag_to_rq(ub->tag_set.tags[qid], tag); - if (WARN_ON_ONCE(unlikely(!req))) - return; - - if (req_op(req) == REQ_OP_ZONE_APPEND) - req->__sector = ub_cmd->zone_append_lba; - - if (likely(!blk_should_fake_timeout(req->q))) - ublk_put_req_ref(ubq, req); -} - static void __ublk_fail_req(struct ublk_queue *ubq, struct ublk_io *io, struct request *req) { @@ -1642,17 +1701,8 @@ static void ublk_abort_queue(struct ublk_device *ub, struct ublk_queue *ubq) for (i = 0; i < ubq->q_depth; i++) { struct ublk_io *io = &ubq->ios[i]; - if (!(io->flags & UBLK_IO_FLAG_ACTIVE)) { - struct request *rq; - - /* - * Either we fail the request or ublk_rq_task_work_cb - * will do it - */ - rq = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], i); - if (rq && blk_mq_request_started(rq)) - __ublk_fail_req(ubq, io, rq); - } + if (io->flags & UBLK_IO_FLAG_OWNED_BY_SRV) + __ublk_fail_req(ubq, io, io->req); } } @@ -1708,7 +1758,7 @@ static void ublk_cancel_cmd(struct ublk_queue *ubq, unsigned tag, * that ublk_dispatch_req() is always called */ req = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], tag); - if (req && blk_mq_request_started(req)) + if (req && blk_mq_request_started(req) && req->tag == tag) return; spin_lock(&ubq->cancel_lock); @@ -1742,6 +1792,7 @@ static void ublk_uring_cmd_cancel_fn(struct io_uring_cmd *cmd, struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); struct ublk_queue *ubq = pdu->ubq; struct task_struct *task; + struct ublk_io *io; if (WARN_ON_ONCE(!ubq)) return; @@ -1750,13 +1801,14 @@ static void ublk_uring_cmd_cancel_fn(struct io_uring_cmd *cmd, return; task = io_uring_cmd_get_task(cmd); - if (WARN_ON_ONCE(task && task != ubq->ubq_daemon)) + io = &ubq->ios[pdu->tag]; + if (WARN_ON_ONCE(task && task != io->task)) return; if (!ubq->canceling) ublk_start_cancel(ubq); - WARN_ON_ONCE(ubq->ios[pdu->tag].cmd != cmd); + WARN_ON_ONCE(io->cmd != cmd); ublk_cancel_cmd(ubq, pdu->tag, issue_flags); } @@ -1889,8 +1941,6 @@ static void ublk_mark_io_ready(struct ublk_device *ub, struct ublk_queue *ubq) { ubq->nr_io_ready++; if (ublk_queue_ready(ubq)) { - ubq->ubq_daemon = current; - get_task_struct(ubq->ubq_daemon); ub->nr_queues_ready++; if (capable(CAP_SYS_ADMIN)) @@ -1940,6 +1990,20 @@ static inline void ublk_prep_cancel(struct io_uring_cmd *cmd, io_uring_cmd_mark_cancelable(cmd, issue_flags); } +static inline int ublk_set_auto_buf_reg(struct io_uring_cmd *cmd) +{ + struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd); + + pdu->buf = ublk_sqe_addr_to_auto_buf_reg(READ_ONCE(cmd->sqe->addr)); + + if (pdu->buf.reserved0 || pdu->buf.reserved1) + return -EINVAL; + + if (pdu->buf.flags & ~UBLK_AUTO_BUF_REG_F_MASK) + return -EINVAL; + return 0; +} + static void ublk_io_release(void *priv) { struct request *rq = priv; @@ -1953,16 +2017,12 @@ static int ublk_register_io_buf(struct io_uring_cmd *cmd, unsigned int index, unsigned int issue_flags) { struct ublk_device *ub = cmd->file->private_data; - const struct ublk_io *io = &ubq->ios[tag]; struct request *req; int ret; if (!ublk_support_zero_copy(ubq)) return -EINVAL; - if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) - return -EINVAL; - req = __ublk_check_and_get_req(ub, ubq, tag, 0); if (!req) return -EINVAL; @@ -1978,17 +2038,12 @@ static int ublk_register_io_buf(struct io_uring_cmd *cmd, } static int ublk_unregister_io_buf(struct io_uring_cmd *cmd, - const struct ublk_queue *ubq, unsigned int tag, + const struct ublk_queue *ubq, unsigned int index, unsigned int issue_flags) { - const struct ublk_io *io = &ubq->ios[tag]; - if (!ublk_support_zero_copy(ubq)) return -EINVAL; - if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) - return -EINVAL; - return io_buffer_unregister_bvec(cmd, index, issue_flags); } @@ -2031,18 +2086,109 @@ static int ublk_fetch(struct io_uring_cmd *cmd, struct ublk_queue *ubq, goto out; } + if (ublk_support_auto_buf_reg(ubq)) { + ret = ublk_set_auto_buf_reg(cmd); + if (ret) + goto out; + } + ublk_fill_io_cmd(io, cmd, buf_addr); + WRITE_ONCE(io->task, get_task_struct(current)); ublk_mark_io_ready(ub, ubq); out: mutex_unlock(&ub->mutex); return ret; } +static int ublk_commit_and_fetch(const struct ublk_queue *ubq, + struct ublk_io *io, struct io_uring_cmd *cmd, + const struct ublksrv_io_cmd *ub_cmd, + unsigned int issue_flags) +{ + struct request *req = io->req; + + if (ublk_need_map_io(ubq)) { + /* + * COMMIT_AND_FETCH_REQ has to provide IO buffer if + * NEED GET DATA is not enabled or it is Read IO. + */ + if (!ub_cmd->addr && (!ublk_need_get_data(ubq) || + req_op(req) == REQ_OP_READ)) + return -EINVAL; + } else if (req_op(req) != REQ_OP_ZONE_APPEND && ub_cmd->addr) { + /* + * User copy requires addr to be unset when command is + * not zone append + */ + return -EINVAL; + } + + if (ublk_support_auto_buf_reg(ubq)) { + int ret; + + /* + * `UBLK_F_AUTO_BUF_REG` only works iff `UBLK_IO_FETCH_REQ` + * and `UBLK_IO_COMMIT_AND_FETCH_REQ` are issued from same + * `io_ring_ctx`. + * + * If this uring_cmd's io_ring_ctx isn't same with the + * one for registering the buffer, it is ublk server's + * responsibility for unregistering the buffer, otherwise + * this ublk request gets stuck. + */ + if (io->flags & UBLK_IO_FLAG_AUTO_BUF_REG) { + struct ublk_rq_data *data = blk_mq_rq_to_pdu(req); + + if (data->buf_ctx_handle == io_uring_cmd_ctx_handle(cmd)) + io_buffer_unregister_bvec(cmd, data->buf_index, + issue_flags); + io->flags &= ~UBLK_IO_FLAG_AUTO_BUF_REG; + } + + ret = ublk_set_auto_buf_reg(cmd); + if (ret) + return ret; + } + + ublk_fill_io_cmd(io, cmd, ub_cmd->addr); + + /* now this cmd slot is owned by ublk driver */ + io->flags &= ~UBLK_IO_FLAG_OWNED_BY_SRV; + io->res = ub_cmd->result; + + if (req_op(req) == REQ_OP_ZONE_APPEND) + req->__sector = ub_cmd->zone_append_lba; + + if (likely(!blk_should_fake_timeout(req->q))) + ublk_put_req_ref(ubq, req); + + return 0; +} + +static bool ublk_get_data(const struct ublk_queue *ubq, struct ublk_io *io, + struct request *req) +{ + /* + * We have handled UBLK_IO_NEED_GET_DATA command, + * so clear UBLK_IO_FLAG_NEED_GET_DATA now and just + * do the copy work. + */ + io->flags &= ~UBLK_IO_FLAG_NEED_GET_DATA; + /* update iod->addr because ublksrv may have passed a new io buffer */ + ublk_get_iod(ubq, req->tag)->addr = io->addr; + pr_devel("%s: update iod->addr: qid %d tag %d io_flags %x addr %llx\n", + __func__, ubq->q_id, req->tag, io->flags, + ublk_get_iod(ubq, req->tag)->addr); + + return ublk_start_io(ubq, req, io); +} + static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags, const struct ublksrv_io_cmd *ub_cmd) { struct ublk_device *ub = cmd->file->private_data; + struct task_struct *task; struct ublk_queue *ubq; struct ublk_io *io; u32 cmd_op = cmd->cmd_op; @@ -2058,16 +2204,14 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, goto out; ubq = ublk_get_queue(ub, ub_cmd->q_id); - if (!ubq || ub_cmd->q_id != ubq->q_id) - goto out; - - if (ubq->ubq_daemon && ubq->ubq_daemon != current) - goto out; if (tag >= ubq->q_depth) goto out; io = &ubq->ios[tag]; + task = READ_ONCE(io->task); + if (task && task != current) + goto out; /* there is pending io cmd, something must be wrong */ if (io->flags & UBLK_IO_FLAG_ACTIVE) { @@ -2075,6 +2219,11 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, goto out; } + /* only UBLK_IO_FETCH_REQ is allowed if io is not OWNED_BY_SRV */ + if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV) && + _IOC_NR(cmd_op) != UBLK_IO_FETCH_REQ) + goto out; + /* * ensure that the user issues UBLK_IO_NEED_GET_DATA * iff the driver have set the UBLK_IO_FLAG_NEED_GET_DATA. @@ -2092,45 +2241,31 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, case UBLK_IO_REGISTER_IO_BUF: return ublk_register_io_buf(cmd, ubq, tag, ub_cmd->addr, issue_flags); case UBLK_IO_UNREGISTER_IO_BUF: - return ublk_unregister_io_buf(cmd, ubq, tag, ub_cmd->addr, issue_flags); + return ublk_unregister_io_buf(cmd, ubq, ub_cmd->addr, issue_flags); case UBLK_IO_FETCH_REQ: ret = ublk_fetch(cmd, ubq, io, ub_cmd->addr); if (ret) goto out; break; case UBLK_IO_COMMIT_AND_FETCH_REQ: - req = blk_mq_tag_to_rq(ub->tag_set.tags[ub_cmd->q_id], tag); - - if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) - goto out; - - if (ublk_need_map_io(ubq)) { - /* - * COMMIT_AND_FETCH_REQ has to provide IO buffer if - * NEED GET DATA is not enabled or it is Read IO. - */ - if (!ub_cmd->addr && (!ublk_need_get_data(ubq) || - req_op(req) == REQ_OP_READ)) - goto out; - } else if (req_op(req) != REQ_OP_ZONE_APPEND && ub_cmd->addr) { - /* - * User copy requires addr to be unset when command is - * not zone append - */ - ret = -EINVAL; + ret = ublk_commit_and_fetch(ubq, io, cmd, ub_cmd, issue_flags); + if (ret) goto out; - } - - ublk_fill_io_cmd(io, cmd, ub_cmd->addr); - ublk_commit_completion(ub, ub_cmd); break; case UBLK_IO_NEED_GET_DATA: - if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) - goto out; + /* + * ublk_get_data() may fail and fallback to requeue, so keep + * uring_cmd active first and prepare for handling new requeued + * request + */ + req = io->req; ublk_fill_io_cmd(io, cmd, ub_cmd->addr); - req = blk_mq_tag_to_rq(ub->tag_set.tags[ub_cmd->q_id], tag); - ublk_dispatch_req(ubq, req, issue_flags); - return -EIOCBQUEUED; + io->flags &= ~UBLK_IO_FLAG_OWNED_BY_SRV; + if (likely(ublk_get_data(ubq, io, req))) { + __ublk_prep_compl_io_cmd(io, req); + return UBLK_IO_RES_OK; + } + break; default: goto out; } @@ -2334,9 +2469,14 @@ static void ublk_deinit_queue(struct ublk_device *ub, int q_id) { int size = ublk_queue_cmd_buf_size(ub, q_id); struct ublk_queue *ubq = ublk_get_queue(ub, q_id); + int i; + + for (i = 0; i < ubq->q_depth; i++) { + struct ublk_io *io = &ubq->ios[i]; + if (io->task) + put_task_struct(io->task); + } - if (ubq->ubq_daemon) - put_task_struct(ubq->ubq_daemon); if (ubq->io_cmd_buf) free_pages((unsigned long)ubq->io_cmd_buf, get_order(size)); } @@ -2710,6 +2850,10 @@ static int ublk_ctrl_add_dev(const struct ublksrv_ctrl_cmd *header) if (copy_from_user(&info, argp, sizeof(info))) return -EFAULT; + if (info.queue_depth > UBLK_MAX_QUEUE_DEPTH || !info.queue_depth || + info.nr_hw_queues > UBLK_MAX_NR_QUEUES || !info.nr_hw_queues) + return -EINVAL; + if (capable(CAP_SYS_ADMIN)) info.flags &= ~UBLK_F_UNPRIVILEGED_DEV; else if (!(info.flags & UBLK_F_UNPRIVILEGED_DEV)) @@ -2728,6 +2872,11 @@ static int ublk_ctrl_add_dev(const struct ublksrv_ctrl_cmd *header) return -EINVAL; } + if ((info.flags & UBLK_F_QUIESCE) && !(info.flags & UBLK_F_USER_RECOVERY)) { + pr_warn("UBLK_F_QUIESCE requires UBLK_F_USER_RECOVERY\n"); + return -EINVAL; + } + /* * unprivileged device can't be trusted, but RECOVERY and * RECOVERY_REISSUE still may hang error handling, so can't @@ -2744,8 +2893,11 @@ static int ublk_ctrl_add_dev(const struct ublksrv_ctrl_cmd *header) * For USER_COPY, we depends on userspace to fill request * buffer by pwrite() to ublk char device, which can't be * used for unprivileged device + * + * Same with zero copy or auto buffer register. */ - if (info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY)) + if (info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY | + UBLK_F_AUTO_BUF_REG)) return -EINVAL; } @@ -2800,10 +2952,12 @@ static int ublk_ctrl_add_dev(const struct ublksrv_ctrl_cmd *header) ub->dev_info.flags &= UBLK_F_ALL; ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE | - UBLK_F_URING_CMD_COMP_IN_TASK; + UBLK_F_URING_CMD_COMP_IN_TASK | + UBLK_F_PER_IO_DAEMON; /* GET_DATA isn't needed any more with USER_COPY or ZERO COPY */ - if (ub->dev_info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY)) + if (ub->dev_info.flags & (UBLK_F_USER_COPY | UBLK_F_SUPPORT_ZERO_COPY | + UBLK_F_AUTO_BUF_REG)) ub->dev_info.flags &= ~UBLK_F_NEED_GET_DATA; /* @@ -3064,14 +3218,14 @@ static int ublk_ctrl_end_recovery(struct ublk_device *ub, int ublksrv_pid = (int)header->data[0]; int ret = -EINVAL; - pr_devel("%s: Waiting for new ubq_daemons(nr: %d) are ready, dev id %d...\n", - __func__, ub->dev_info.nr_hw_queues, header->dev_id); - /* wait until new ubq_daemon sending all FETCH_REQ */ + pr_devel("%s: Waiting for all FETCH_REQs, dev id %d...\n", __func__, + header->dev_id); + if (wait_for_completion_interruptible(&ub->completion)) return -EINTR; - pr_devel("%s: All new ubq_daemons(nr: %d) are ready, dev id %d\n", - __func__, ub->dev_info.nr_hw_queues, header->dev_id); + pr_devel("%s: All FETCH_REQs received, dev id %d\n", __func__, + header->dev_id); mutex_lock(&ub->mutex); if (ublk_nosrv_should_stop_dev(ub)) @@ -3106,6 +3260,127 @@ static int ublk_ctrl_get_features(const struct ublksrv_ctrl_cmd *header) return 0; } +static void ublk_ctrl_set_size(struct ublk_device *ub, const struct ublksrv_ctrl_cmd *header) +{ + struct ublk_param_basic *p = &ub->params.basic; + u64 new_size = header->data[0]; + + mutex_lock(&ub->mutex); + p->dev_sectors = new_size; + set_capacity_and_notify(ub->ub_disk, p->dev_sectors); + mutex_unlock(&ub->mutex); +} + +struct count_busy { + const struct ublk_queue *ubq; + unsigned int nr_busy; +}; + +static bool ublk_count_busy_req(struct request *rq, void *data) +{ + struct count_busy *idle = data; + + if (!blk_mq_request_started(rq) && rq->mq_hctx->driver_data == idle->ubq) + idle->nr_busy += 1; + return true; +} + +/* uring_cmd is guaranteed to be active if the associated request is idle */ +static bool ubq_has_idle_io(const struct ublk_queue *ubq) +{ + struct count_busy data = { + .ubq = ubq, + }; + + blk_mq_tagset_busy_iter(&ubq->dev->tag_set, ublk_count_busy_req, &data); + return data.nr_busy < ubq->q_depth; +} + +/* Wait until each hw queue has at least one idle IO */ +static int ublk_wait_for_idle_io(struct ublk_device *ub, + unsigned int timeout_ms) +{ + unsigned int elapsed = 0; + int ret; + + while (elapsed < timeout_ms && !signal_pending(current)) { + unsigned int queues_cancelable = 0; + int i; + + for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { + struct ublk_queue *ubq = ublk_get_queue(ub, i); + + queues_cancelable += !!ubq_has_idle_io(ubq); + } + + /* + * Each queue needs at least one active command for + * notifying ublk server + */ + if (queues_cancelable == ub->dev_info.nr_hw_queues) + break; + + msleep(UBLK_REQUEUE_DELAY_MS); + elapsed += UBLK_REQUEUE_DELAY_MS; + } + + if (signal_pending(current)) + ret = -EINTR; + else if (elapsed >= timeout_ms) + ret = -EBUSY; + else + ret = 0; + + return ret; +} + +static int ublk_ctrl_quiesce_dev(struct ublk_device *ub, + const struct ublksrv_ctrl_cmd *header) +{ + /* zero means wait forever */ + u64 timeout_ms = header->data[0]; + struct gendisk *disk; + int i, ret = -ENODEV; + + if (!(ub->dev_info.flags & UBLK_F_QUIESCE)) + return -EOPNOTSUPP; + + mutex_lock(&ub->mutex); + disk = ublk_get_disk(ub); + if (!disk) + goto unlock; + if (ub->dev_info.state == UBLK_S_DEV_DEAD) + goto put_disk; + + ret = 0; + /* already in expected state */ + if (ub->dev_info.state != UBLK_S_DEV_LIVE) + goto put_disk; + + /* Mark all queues as canceling */ + blk_mq_quiesce_queue(disk->queue); + for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { + struct ublk_queue *ubq = ublk_get_queue(ub, i); + + ubq->canceling = true; + } + blk_mq_unquiesce_queue(disk->queue); + + if (!timeout_ms) + timeout_ms = UINT_MAX; + ret = ublk_wait_for_idle_io(ub, timeout_ms); + +put_disk: + ublk_put_disk(disk); +unlock: + mutex_unlock(&ub->mutex); + + /* Cancel pending uring_cmd */ + if (!ret) + ublk_cancel_dev(ub); + return ret; +} + /* * All control commands are sent via /dev/ublk-control, so we have to check * the destination device's permission @@ -3191,6 +3466,8 @@ static int ublk_ctrl_uring_cmd_permission(struct ublk_device *ub, case UBLK_CMD_SET_PARAMS: case UBLK_CMD_START_USER_RECOVERY: case UBLK_CMD_END_USER_RECOVERY: + case UBLK_CMD_UPDATE_SIZE: + case UBLK_CMD_QUIESCE_DEV: mask = MAY_READ | MAY_WRITE; break; default: @@ -3282,6 +3559,13 @@ static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd, case UBLK_CMD_END_USER_RECOVERY: ret = ublk_ctrl_end_recovery(ub, header); break; + case UBLK_CMD_UPDATE_SIZE: + ublk_ctrl_set_size(ub, header); + ret = 0; + break; + case UBLK_CMD_QUIESCE_DEV: + ret = ublk_ctrl_quiesce_dev(ub, header); + break; default: ret = -EOPNOTSUPP; break; @@ -3315,6 +3599,7 @@ static int __init ublk_init(void) BUILD_BUG_ON((u64)UBLKSRV_IO_BUF_OFFSET + UBLKSRV_IO_BUF_TOTAL_SIZE < UBLKSRV_IO_BUF_OFFSET); + BUILD_BUG_ON(sizeof(struct ublk_auto_buf_reg) != 8); init_waitqueue_head(&ublk_idr_wq); |