From patchwork Wed Feb 22 13:25:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiaoguang Wang X-Patchwork-Id: 13149147 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD3E7C6FD19 for ; Wed, 22 Feb 2023 13:26:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231292AbjBVN0R (ORCPT ); Wed, 22 Feb 2023 08:26:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231185AbjBVN0P (ORCPT ); Wed, 22 Feb 2023 08:26:15 -0500 Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8FE13B0E4; Wed, 22 Feb 2023 05:25:46 -0800 (PST) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R131e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046056;MF=xiaoguang.wang@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0VcH06.._1677072337; Received: from localhost(mailfrom:xiaoguang.wang@linux.alibaba.com fp:SMTPD_---0VcH06.._1677072337) by smtp.aliyun-inc.com; Wed, 22 Feb 2023 21:25:38 +0800 From: Xiaoguang Wang To: linux-block@vger.kernel.org, io-uring@vger.kernel.org, bpf@vger.kernel.org Cc: ming.lei@redhat.com, axboe@kernel.dk, asml.silence@gmail.com, ZiyangZhang@linux.alibaba.com Subject: [RFC v2 4/4] ublk_drv: add ebpf support Date: Wed, 22 Feb 2023 21:25:34 +0800 Message-Id: <20230222132534.114574-5-xiaoguang.wang@linux.alibaba.com> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20230222132534.114574-1-xiaoguang.wang@linux.alibaba.com> References: <20230222132534.114574-1-xiaoguang.wang@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Currenly only one bpf_ublk_queue_sqe() ebpf is added, ublksrv target can use this helper to write ebpf prog to support ublk kernel & usersapce zero copy, please see ublksrv test codes for more info. Signed-off-by: Xiaoguang Wang --- drivers/block/ublk_drv.c | 263 +++++++++++++++++++++++++++++++-- include/uapi/linux/bpf.h | 1 + include/uapi/linux/ublk_cmd.h | 18 +++ kernel/bpf/verifier.c | 3 +- scripts/bpf_doc.py | 4 + tools/include/uapi/linux/bpf.h | 9 ++ 6 files changed, 286 insertions(+), 12 deletions(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index b628e9eaefa6..d17ddb6fc27f 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -105,6 +105,12 @@ struct ublk_uring_cmd_pdu { */ #define UBLK_IO_FLAG_NEED_GET_DATA 0x08 +/* + * UBLK_IO_FLAG_BPF is set if IO command has be handled by ebpf prog instead + * of user space daemon. + */ +#define UBLK_IO_FLAG_BPF 0x10 + struct ublk_io { /* userspace buffer address from io cmd */ __u64 addr; @@ -114,6 +120,11 @@ struct ublk_io { struct io_uring_cmd *cmd; }; +struct ublk_req_iter { + struct io_fixed_iter fixed_iter; + struct bio_vec *bvec; +}; + struct ublk_queue { int q_id; int q_depth; @@ -163,6 +174,9 @@ struct ublk_device { unsigned int nr_queues_ready; atomic_t nr_aborted_queues; + struct bpf_prog *io_bpf_prog; + struct ublk_req_iter *iter_table; + /* * Our ubq->daemon may be killed without any notification, so * monitor each queue's daemon periodically @@ -189,10 +203,48 @@ static DEFINE_MUTEX(ublk_ctl_mutex); static struct miscdevice ublk_misc; +struct ublk_io_bpf_ctx { + struct ublk_bpf_ctx ctx; + struct ublk_device *ub; +}; + +static inline struct ublk_req_iter *ublk_get_req_iter(struct ublk_device *ub, + int qid, int tag) +{ + return &(ub->iter_table[qid * ub->dev_info.queue_depth + tag]); +} + +BPF_CALL_4(bpf_ublk_queue_sqe, struct ublk_io_bpf_ctx *, bpf_ctx, + struct io_uring_sqe *, sqe, u32, sqe_len, u32, fd) +{ + struct ublk_req_iter *req_iter; + u16 q_id = bpf_ctx->ctx.q_id; + u16 tag = bpf_ctx->ctx.tag; + + req_iter = ublk_get_req_iter(bpf_ctx->ub, q_id, tag); + io_uring_submit_sqe(fd, sqe, sqe_len, &(req_iter->fixed_iter)); + return 0; +} + +const struct bpf_func_proto ublk_bpf_queue_sqe_proto = { + .func = bpf_ublk_queue_sqe, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_ANYTHING, + .arg2_type = ARG_ANYTHING, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_ANYTHING, +}; + static const struct bpf_func_proto * ublk_bpf_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { - return bpf_base_func_proto(func_id); + switch (func_id) { + case BPF_FUNC_ublk_queue_sqe: + return &ublk_bpf_queue_sqe_proto; + default: + return bpf_base_func_proto(func_id); + } } static bool ublk_bpf_is_valid_access(int off, int size, @@ -200,6 +252,23 @@ static bool ublk_bpf_is_valid_access(int off, int size, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { + if (off < 0 || off >= sizeof(struct ublk_bpf_ctx)) + return false; + if (off % size != 0) + return false; + + switch (off) { + case offsetof(struct ublk_bpf_ctx, q_id): + return size == sizeof_field(struct ublk_bpf_ctx, q_id); + case offsetof(struct ublk_bpf_ctx, tag): + return size == sizeof_field(struct ublk_bpf_ctx, tag); + case offsetof(struct ublk_bpf_ctx, op): + return size == sizeof_field(struct ublk_bpf_ctx, op); + case offsetof(struct ublk_bpf_ctx, nr_sectors): + return size == sizeof_field(struct ublk_bpf_ctx, nr_sectors); + case offsetof(struct ublk_bpf_ctx, start_sector): + return size == sizeof_field(struct ublk_bpf_ctx, start_sector); + } return false; } @@ -324,7 +393,7 @@ static void ublk_put_device(struct ublk_device *ub) static inline struct ublk_queue *ublk_get_queue(struct ublk_device *dev, int qid) { - return (struct ublk_queue *)&(dev->__queues[qid * dev->queue_size]); + return (struct ublk_queue *)&(dev->__queues[qid * dev->queue_size]); } static inline bool ublk_rq_has_data(const struct request *rq) @@ -618,7 +687,6 @@ static void ublk_complete_rq(struct request *req) { struct ublk_queue *ubq = req->mq_hctx->driver_data; struct ublk_io *io = &ubq->ios[req->tag]; - unsigned int unmapped_bytes; /* failed read IO if nothing is read */ if (!io->res && req_op(req) == REQ_OP_READ) @@ -641,15 +709,19 @@ static void ublk_complete_rq(struct request *req) } /* for READ request, writing data in iod->addr to rq buffers */ - unmapped_bytes = ublk_unmap_io(ubq, req, io); + if (likely(!(io->flags & UBLK_IO_FLAG_BPF))) { + unsigned int unmapped_bytes; - /* - * Extremely impossible since we got data filled in just before - * - * Re-read simply for this unlikely case. - */ - if (unlikely(unmapped_bytes < io->res)) - io->res = unmapped_bytes; + unmapped_bytes = ublk_unmap_io(ubq, req, io); + + /* + * Extremely impossible since we got data filled in just before + * + * Re-read simply for this unlikely case. + */ + if (unlikely(unmapped_bytes < io->res)) + io->res = unmapped_bytes; + } if (blk_update_request(req, BLK_STS_OK, io->res)) blk_mq_requeue_request(req, true); @@ -708,12 +780,92 @@ static inline void __ublk_abort_rq(struct ublk_queue *ubq, mod_delayed_work(system_wq, &ubq->dev->monitor_work, 0); } +static int ublk_init_uring_fixed_iter(struct ublk_queue *ubq, struct request *rq) +{ + struct ublk_device *ub = ubq->dev; + struct bio *bio = rq->bio; + struct bio_vec *bvec; + struct req_iterator rq_iter; + struct bio_vec tmp; + int nr_bvec = 0; + struct ublk_req_iter *req_iter; + unsigned int rw, offset; + + req_iter = ublk_get_req_iter(ub, ubq->q_id, rq->tag); + if (req_op(rq) == REQ_OP_READ) + rw = ITER_DEST; + else + rw = ITER_SOURCE; + + rq_for_each_bvec(tmp, rq, rq_iter) + nr_bvec++; + if (rq->bio != rq->biotail) { + bvec = kmalloc_array(nr_bvec, sizeof(struct bio_vec), GFP_NOIO); + if (!bvec) + return -EIO; + req_iter->bvec = bvec; + + /* + * The bios of the request may be started from the middle of + * the 'bvec' because of bio splitting, so we can't directly + * copy bio->bi_iov_vec to new bvec. The rq_for_each_bvec + * API will take care of all details for us. + */ + rq_for_each_bvec(tmp, rq, rq_iter) { + *bvec = tmp; + bvec++; + } + bvec = req_iter->bvec; + offset = 0; + } else { + /* + * Same here, this bio may be started from the middle of the + * 'bvec' because of bio splitting, so offset from the bvec + * must be passed to iov iterator + */ + offset = bio->bi_iter.bi_bvec_done; + bvec = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter); + req_iter->bvec = NULL; + } + + iov_iter_bvec(&(req_iter->fixed_iter.iter), rw, bvec, nr_bvec, blk_rq_bytes(rq)); + req_iter->fixed_iter.iter.iov_offset = offset; + return 0; +} + +static int ublk_run_bpf_prog(struct ublk_queue *ubq, struct request *rq) +{ + int ret; + struct ublk_device *ub = ubq->dev; + struct ublk_io_bpf_ctx bpf_ctx; + u32 bpf_act; + + if (!ub->io_bpf_prog) + return 0; + + ret = ublk_init_uring_fixed_iter(ubq, rq); + if (ret < 0) + return UBLK_BPF_IO_ABORTED; + + bpf_ctx.ub = ub; + bpf_ctx.ctx.q_id = ubq->q_id; + bpf_ctx.ctx.tag = rq->tag; + bpf_ctx.ctx.op = req_op(rq); + bpf_ctx.ctx.nr_sectors = blk_rq_sectors(rq); + bpf_ctx.ctx.start_sector = blk_rq_pos(rq); + bpf_act = bpf_prog_run_pin_on_cpu(ub->io_bpf_prog, &bpf_ctx); + return bpf_act; +} + static inline void __ublk_rq_task_work(struct request *req) { struct ublk_queue *ubq = req->mq_hctx->driver_data; + struct ublk_device *ub = ubq->dev; int tag = req->tag; struct ublk_io *io = &ubq->ios[tag]; unsigned int mapped_bytes; + u32 bpf_act; + bool io_done = false; 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, @@ -762,6 +914,10 @@ static inline void __ublk_rq_task_work(struct request *req) ublk_get_iod(ubq, req->tag)->addr); } + if (unlikely(ub->io_bpf_prog)) + goto call_ebpf; + +normal_path: mapped_bytes = ublk_map_io(ubq, req, io); /* partially mapped, update io descriptor */ @@ -784,7 +940,21 @@ static inline void __ublk_rq_task_work(struct request *req) mapped_bytes >> 9; } + if (!io_done) + ubq_complete_io_cmd(io, UBLK_IO_RES_OK); + return; + +call_ebpf: ubq_complete_io_cmd(io, UBLK_IO_RES_OK); + bpf_act = ublk_run_bpf_prog(ubq, req); + switch (bpf_act) { + case UBLK_BPF_IO_ABORTED: + case UBLK_BPF_IO_DROP: + case UBLK_BPF_IO_PASS: + io_done = true; + goto normal_path; + } + io->flags |= UBLK_IO_FLAG_BPF; } static inline void ublk_forward_io_cmds(struct ublk_queue *ubq) @@ -1231,6 +1401,10 @@ static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) __func__, cmd->cmd_op, ub_cmd->q_id, tag, ub_cmd->result); + /* To workaround task_work_add is not exported. */ + if (unlikely(ub->io_bpf_prog && !(cmd->flags & IORING_URING_CMD_UNLOCK))) + goto out; + if (!(issue_flags & IO_URING_F_SQE128)) goto out; @@ -1295,6 +1469,14 @@ static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) io->flags |= UBLK_IO_FLAG_ACTIVE; io->cmd = cmd; ublk_commit_completion(ub, ub_cmd); + if (io->flags & UBLK_IO_FLAG_BPF) { + struct ublk_req_iter *req_iter; + + req_iter = ublk_get_req_iter(ub, ubq->q_id, tag); + io->flags &= ~UBLK_IO_FLAG_BPF; + kfree(req_iter->bvec); + req_iter->bvec = NULL; + } break; case UBLK_IO_NEED_GET_DATA: if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)) @@ -2009,6 +2191,59 @@ static int ublk_ctrl_end_recovery(struct io_uring_cmd *cmd) return ret; } +static int ublk_ctrl_reg_bpf_prog(struct io_uring_cmd *cmd) +{ + struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + struct ublk_device *ub; + struct bpf_prog *prog; + int ret = 0, nr_queues, depth; + + ub = ublk_get_device_from_id(header->dev_id); + if (!ub) + return -EINVAL; + + mutex_lock(&ub->mutex); + nr_queues = ub->dev_info.nr_hw_queues; + depth = ub->dev_info.queue_depth; + ub->iter_table = kzalloc(sizeof(struct ublk_req_iter) * depth * nr_queues, + GFP_KERNEL); + if (!ub->iter_table) { + ret = -ENOMEM; + goto out_unlock; + } + + prog = bpf_prog_get_type(header->data[0], BPF_PROG_TYPE_UBLK); + if (IS_ERR(prog)) { + kfree(ub->iter_table); + ret = PTR_ERR(prog); + goto out_unlock; + } + ub->io_bpf_prog = prog; + +out_unlock: + mutex_unlock(&ub->mutex); + ublk_put_device(ub); + return ret; +} + +static int ublk_ctrl_unreg_bpf_prog(struct io_uring_cmd *cmd) +{ + struct ublksrv_ctrl_cmd *header = (struct ublksrv_ctrl_cmd *)cmd->cmd; + struct ublk_device *ub; + + ub = ublk_get_device_from_id(header->dev_id); + if (!ub) + return -EINVAL; + + mutex_lock(&ub->mutex); + bpf_prog_put(ub->io_bpf_prog); + ub->io_bpf_prog = NULL; + kfree(ub->iter_table); + ub->iter_table = NULL; + mutex_unlock(&ub->mutex); + ublk_put_device(ub); + return 0; +} static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) { @@ -2059,6 +2294,12 @@ static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd, case UBLK_CMD_END_USER_RECOVERY: ret = ublk_ctrl_end_recovery(cmd); break; + case UBLK_CMD_REG_BPF_PROG: + ret = ublk_ctrl_reg_bpf_prog(cmd); + break; + case UBLK_CMD_UNREG_BPF_PROG: + ret = ublk_ctrl_unreg_bpf_prog(cmd); + break; default: break; } diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 515b7b995b3a..578d65e9f30e 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5699,6 +5699,7 @@ union bpf_attr { FN(user_ringbuf_drain, 209, ##ctx) \ FN(cgrp_storage_get, 210, ##ctx) \ FN(cgrp_storage_delete, 211, ##ctx) \ + FN(ublk_queue_sqe, 212, ##ctx) \ /* */ /* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h index 8f88e3a29998..fbfe5145221e 100644 --- a/include/uapi/linux/ublk_cmd.h +++ b/include/uapi/linux/ublk_cmd.h @@ -17,6 +17,8 @@ #define UBLK_CMD_STOP_DEV 0x07 #define UBLK_CMD_SET_PARAMS 0x08 #define UBLK_CMD_GET_PARAMS 0x09 +#define UBLK_CMD_REG_BPF_PROG 0x0a +#define UBLK_CMD_UNREG_BPF_PROG 0x0b #define UBLK_CMD_START_USER_RECOVERY 0x10 #define UBLK_CMD_END_USER_RECOVERY 0x11 /* @@ -230,4 +232,20 @@ struct ublk_params { struct ublk_param_discard discard; }; +struct ublk_bpf_ctx { + __u32 t_val; + __u16 q_id; + __u16 tag; + __u8 op; + __u32 nr_sectors; + __u64 start_sector; +}; + +enum { + UBLK_BPF_IO_ABORTED = 0, + UBLK_BPF_IO_DROP, + UBLK_BPF_IO_PASS, + UBLK_BPF_IO_REDIRECT, +}; + #endif diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 1e5bc89aea36..b1645a3d93a2 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -24,6 +24,7 @@ #include #include #include +#include #include "disasm.h" @@ -12236,7 +12237,7 @@ static int check_return_code(struct bpf_verifier_env *env) break; case BPF_PROG_TYPE_UBLK: - range = tnum_const(0); + range = tnum_range(UBLK_BPF_IO_ABORTED, UBLK_BPF_IO_REDIRECT); break; case BPF_PROG_TYPE_EXT: diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py index e8d90829f23e..f8672294e145 100755 --- a/scripts/bpf_doc.py +++ b/scripts/bpf_doc.py @@ -700,6 +700,8 @@ class PrinterHelpers(Printer): 'struct bpf_dynptr', 'struct iphdr', 'struct ipv6hdr', + 'struct ublk_io_bpf_ctx', + 'struct io_uring_sqe', ] known_types = { '...', @@ -755,6 +757,8 @@ class PrinterHelpers(Printer): 'const struct bpf_dynptr', 'struct iphdr', 'struct ipv6hdr', + 'struct ublk_io_bpf_ctx', + 'struct io_uring_sqe', } mapped_types = { 'u8': '__u8', diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 515b7b995b3a..e3a81e576ec1 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5485,6 +5485,14 @@ union bpf_attr { * 0 on success. * * **-ENOENT** if the bpf_local_storage cannot be found. + * + * + * u64 bpf_ublk_queue_sqe(struct ublk_io_bpf_ctx *ctx, struct io_uring_sqe *sqe, u32 offset, u32 len) + * Description + * Submit ublk io requests. + * Return + * 0 on success. + * */ #define ___BPF_FUNC_MAPPER(FN, ctx...) \ FN(unspec, 0, ##ctx) \ @@ -5699,6 +5707,7 @@ union bpf_attr { FN(user_ringbuf_drain, 209, ##ctx) \ FN(cgrp_storage_get, 210, ##ctx) \ FN(cgrp_storage_delete, 211, ##ctx) \ + FN(ublk_queue_sqe, 212, ##ctx) \ /* */ /* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't