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Wed, 6 Sep 2023 16:42:59 +0000 (GMT) From: Nitesh Shetty To: Jens Axboe , Jonathan Corbet , Alasdair Kergon , Mike Snitzer , dm-devel@redhat.com, Keith Busch , Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni , Alexander Viro , Christian Brauner Date: Wed, 6 Sep 2023 22:08:27 +0530 Message-Id: <20230906163844.18754-3-nj.shetty@samsung.com> In-Reply-To: <20230906163844.18754-1-nj.shetty@samsung.com> MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA01Te0xTZxTnu/f2clG7XF7hs3uAXcgGDGjHww+USaKOa9wIYMw2t9AVei2s T/sQNIxVAWWNPARZsMrDwcaACYMp4WEN1DAURgh0PJdSXWBuI4KPBecYupbC5n+/c87v/M75 nS8fhXs9JnlUplLHapRiOZ/cRHTcCAoKtVz7SyIYuh+OWgd/wNHJ0lUcNdtKSLRw4yFAc72n ATIvXuCg6d4uDDU292OozDIB0Py4CUPmmRB06VQ9ga6ZbxHI2n2RRDVfz7ujhoGnGJoqnQeo Y6UGRy0LSwS6OfMiGlkd4MT7MiOzbQRjHdYz7U2fk8z39Z8xPdMGkqkrLucwRXmLJPNgfoZg lq6Pk0zxlSbAPGp/hWmfu4clbTkk25nBiiWsJoBVpqskmUppHH//AdFuUVS0QBgqjEHb+QFK sYKN4+95Jyn07Uy5wys/4KhYrnekksRaLT/8rZ0alV7HBmSotLo4PquWyNWR6jCtWKHVK6Vh SlYXKxQI3oxyED+WZcxUGznqqh3Zww2ThAEYBEbgQUE6EpaNznKMYBPlRfcAaH0w4+4KHgK4 PLuIuYJlAPP6VsiNlif5lYSrYAaw/+4ocAUFGKz7rdzRT1EkHQKHnlHOvA9twOF3PXVrJJxu weD5+jHcKeVNfwQn7FbMiQk6EH7Rdp1wYi4dC6c7R0mnEKTDYYnd05n2oHfAkyecw5wUT3jr /NwaHaf9Yd7VC7hTH9KnPeByxSjhWnUP/Md2BnNhb/jHwBV3F+bBR4vmdTtZsPHcN6SrOR9A 06QJuAq7YMFgCe5cAqeDYGt3uCv9MqwYbMFcg1+ARStz6/pc2Fm9gV+F37bWrutvhROPT6xj BlbbreunKwbwnPEJVgoCTM8ZMj1nyPT/6FqAN4GtrFqrkLLaKLVQyWb9987pKkU7WPsBwfs6 ge32/TALwChgAZDC+T7cRf9liRdXIj52nNWoRBq9nNVaQJTj4Gdxnm+6yvGFlDqRMDJGEBkd HR0ZExEt5PtxFwqqJF60VKxjZSyrZjUbfRjlwTNgh98Vzat8j1UekmEVg4G5/bSsSbF3mCME mpQvIyb0hYWJ237Nk2SHRI1bYopkOXX5xtsNV9OqhtwPphzOfMm2TVEf32VN8U2nujjeW0aq LglyjYacLJxnp+y1upybabGfKrJFCf5f+fxYOjq1mQ7mPUV7OuuDP/zJ55f81Ht+vbsKG45Q vtxcqdmzuSWrvPqom1tq8tj2pdSO7jcuX/wgosz4nt32t9vUJ3HDlw/mtM1KN999NglEebuP dwR2+r1v645f3ZeEEpM99rqn/nm270DQ/p8TquW/L6Dc5OWSxD4yLMG7pPK1I68ry8daGsnU tO6aO3Xw1EBo1pn+O9y5rhU+oc0QC4NxjVb8Lx0ugRSKBAAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrDIsWRmVeSWpSXmKPExsWy7bCSvK7Ymh8pBq8WG1qsP3WM2aJpwl9m i9V3+9ksXh/+xGjx5EA7o8Xed7NZLW4e2MlksXL1USaLSYeuMVo8vTqLyWLvLW2LhW1LWCz2 7D3JYnF51xw2i/nLnrJbLD/+j8nixoSnjBbbfs9ntlj3+j2LxYlb0hbn/x5ndRD1OH9vI4vH 5bOlHptWdbJ5bF5S77H7ZgObx+K+yawevc3v2Dw+Pr3F4vF+31U2j74tqxg9Pm+S89j05C1T AE8Ul01Kak5mWWqRvl0CV8ateV2sBXOtK84uv87SwNhg0MXIySEhYCLxs2UGSxcjF4eQwG5G iQXNu5ggEpISy/4eYYawhSVW/nvODlHUzCSxrr8VyOHgYBPQljj9nwMkLiLQxSzRufMd2CRm gR1MEs//t7GDdAsLREns7mphBLFZBFQlpm3cxwJi8wpYSdzccZENZJCEgL5E/31BkDCngLVE U+NFsHIhoJI7q14zQpQLSpyc+QSslVlAXqJ562zmCYwCs5CkZiFJLWBkWsUomVpQnJuem2xY YJiXWq5XnJhbXJqXrpecn7uJERyhWho7GO/N/6d3iJGJg/EQowQHs5II7zv5bylCvCmJlVWp RfnxRaU5qcWHGKU5WJTEeQ1nzE4REkhPLEnNTk0tSC2CyTJxcEo1MHX75zXuWc3Hl/vha4jV JN43z/Vllidf6OI+F/cntWrz7LY9Z44o3GMU2WGwPPYy0/GWPfUrOjzUNxoEzc+L+sVv8c35 rfeaO0Hv59+N1Zt7ZOf5HbJLb3+9EbT8VNLLwLbTqz36dxy7v61WXU4vZ7734zt8CVNUl9yy PS/ad/SgssKcntOs7q932N0SqI4MUlryimn9hlcCx+YHZ+oveGSdKflq4vmntR5TC64nL7FN 1CoJnZOxvefR/xlfAlvXRsb0TWD6/VvP+etltT+fdtU/O7VGy0iKpZrfuGn6sdbs98EWszZs CmeOvqp6z66mZYevqUJ88ruJG18p9ykWqV4+wWDwzaujxIv7fUtz51klluKMREMt5qLiRAAs M9dqPwMAAA== X-CMS-MailID: 20230906164303epcas5p1c2d3ec21feac347f0f1d68adc97c61f5 X-Msg-Generator: CA X-Sendblock-Type: REQ_APPROVE CMS-TYPE: 105P DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20230906164303epcas5p1c2d3ec21feac347f0f1d68adc97c61f5 References: <20230906163844.18754-1-nj.shetty@samsung.com> X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Subject: [dm-devel] [PATCH v15 02/12] Add infrastructure for copy offload in block and request layer. X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: martin.petersen@oracle.com, linux-doc@vger.kernel.org, gost.dev@samsung.com, Anuj Gupta , linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, mcgrof@kernel.org, linux-fsdevel@vger.kernel.org, Nitesh Shetty Errors-To: dm-devel-bounces@redhat.com Sender: "dm-devel" X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: samsung.com We add two new opcode REQ_OP_COPY_SRC, REQ_OP_COPY_DST. Since copy is a composite operation involving src and dst sectors/lba, each needs to be represented by a separate bio to make it compatible with device mapper. We expect caller to take a plug and send bio with source information, followed by bio with destination information. Once the src bio arrives we form a request and wait for destination bio. Upon arrival of destination we merge these two bio's and send corresponding request down to device driver. Signed-off-by: Nitesh Shetty Signed-off-by: Anuj Gupta --- block/blk-core.c | 7 +++++++ block/blk-merge.c | 41 +++++++++++++++++++++++++++++++++++++++ block/blk.h | 16 +++++++++++++++ block/elevator.h | 1 + include/linux/bio.h | 6 +----- include/linux/blk_types.h | 10 ++++++++++ 6 files changed, 76 insertions(+), 5 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 9d51e9894ece..33aadafdb7f9 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -121,6 +121,8 @@ static const char *const blk_op_name[] = { REQ_OP_NAME(ZONE_FINISH), REQ_OP_NAME(ZONE_APPEND), REQ_OP_NAME(WRITE_ZEROES), + REQ_OP_NAME(COPY_SRC), + REQ_OP_NAME(COPY_DST), REQ_OP_NAME(DRV_IN), REQ_OP_NAME(DRV_OUT), }; @@ -792,6 +794,11 @@ void submit_bio_noacct(struct bio *bio) if (!q->limits.max_write_zeroes_sectors) goto not_supported; break; + case REQ_OP_COPY_SRC: + case REQ_OP_COPY_DST: + if (!q->limits.max_copy_sectors) + goto not_supported; + break; default: break; } diff --git a/block/blk-merge.c b/block/blk-merge.c index 65e75efa9bd3..bcb55ba48107 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -158,6 +158,20 @@ static struct bio *bio_split_write_zeroes(struct bio *bio, return bio_split(bio, lim->max_write_zeroes_sectors, GFP_NOIO, bs); } +static struct bio *bio_split_copy(struct bio *bio, + const struct queue_limits *lim, + unsigned int *nsegs) +{ + *nsegs = 1; + if (bio_sectors(bio) <= lim->max_copy_sectors) + return NULL; + /* + * We don't support splitting for a copy bio. End it with EIO if + * splitting is required and return an error pointer. + */ + return ERR_PTR(-EIO); +} + /* * Return the maximum number of sectors from the start of a bio that may be * submitted as a single request to a block device. If enough sectors remain, @@ -366,6 +380,12 @@ struct bio *__bio_split_to_limits(struct bio *bio, case REQ_OP_WRITE_ZEROES: split = bio_split_write_zeroes(bio, lim, nr_segs, bs); break; + case REQ_OP_COPY_SRC: + case REQ_OP_COPY_DST: + split = bio_split_copy(bio, lim, nr_segs); + if (IS_ERR(split)) + return NULL; + break; default: split = bio_split_rw(bio, lim, nr_segs, bs, get_max_io_size(bio, lim) << SECTOR_SHIFT); @@ -922,6 +942,9 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) if (!rq_mergeable(rq) || !bio_mergeable(bio)) return false; + if (blk_copy_offload_mergable(rq, bio)) + return true; + if (req_op(rq) != bio_op(bio)) return false; @@ -951,6 +974,8 @@ enum elv_merge blk_try_merge(struct request *rq, struct bio *bio) { if (blk_discard_mergable(rq)) return ELEVATOR_DISCARD_MERGE; + else if (blk_copy_offload_mergable(rq, bio)) + return ELEVATOR_COPY_OFFLOAD_MERGE; else if (blk_rq_pos(rq) + blk_rq_sectors(rq) == bio->bi_iter.bi_sector) return ELEVATOR_BACK_MERGE; else if (blk_rq_pos(rq) - bio_sectors(bio) == bio->bi_iter.bi_sector) @@ -1053,6 +1078,20 @@ static enum bio_merge_status bio_attempt_discard_merge(struct request_queue *q, return BIO_MERGE_FAILED; } +static enum bio_merge_status bio_attempt_copy_offload_merge(struct request *req, + struct bio *bio) +{ + if (req->__data_len != bio->bi_iter.bi_size) + return BIO_MERGE_FAILED; + + req->biotail->bi_next = bio; + req->biotail = bio; + req->nr_phys_segments++; + req->__data_len += bio->bi_iter.bi_size; + + return BIO_MERGE_OK; +} + static enum bio_merge_status blk_attempt_bio_merge(struct request_queue *q, struct request *rq, struct bio *bio, @@ -1073,6 +1112,8 @@ static enum bio_merge_status blk_attempt_bio_merge(struct request_queue *q, break; case ELEVATOR_DISCARD_MERGE: return bio_attempt_discard_merge(q, rq, bio); + case ELEVATOR_COPY_OFFLOAD_MERGE: + return bio_attempt_copy_offload_merge(rq, bio); default: return BIO_MERGE_NONE; } diff --git a/block/blk.h b/block/blk.h index 08a358bc0919..b0c17ad635a5 100644 --- a/block/blk.h +++ b/block/blk.h @@ -159,6 +159,20 @@ static inline bool blk_discard_mergable(struct request *req) return false; } +/* + * Copy offload sends a pair of bio with REQ_OP_COPY_SRC and REQ_OP_COPY_DST + * operation by taking a plug. + * Initially SRC bio is sent which forms a request and + * waits for DST bio to arrive. Once DST bio arrives + * we merge it and send request down to driver. + */ +static inline bool blk_copy_offload_mergable(struct request *req, + struct bio *bio) +{ + return (req_op(req) == REQ_OP_COPY_SRC && + bio_op(bio) == REQ_OP_COPY_DST); +} + static inline unsigned int blk_rq_get_max_segments(struct request *rq) { if (req_op(rq) == REQ_OP_DISCARD) @@ -300,6 +314,8 @@ static inline bool bio_may_exceed_limits(struct bio *bio, case REQ_OP_DISCARD: case REQ_OP_SECURE_ERASE: case REQ_OP_WRITE_ZEROES: + case REQ_OP_COPY_SRC: + case REQ_OP_COPY_DST: return true; /* non-trivial splitting decisions */ default: break; diff --git a/block/elevator.h b/block/elevator.h index 7ca3d7b6ed82..eec442bbf384 100644 --- a/block/elevator.h +++ b/block/elevator.h @@ -18,6 +18,7 @@ enum elv_merge { ELEVATOR_FRONT_MERGE = 1, ELEVATOR_BACK_MERGE = 2, ELEVATOR_DISCARD_MERGE = 3, + ELEVATOR_COPY_OFFLOAD_MERGE = 4, }; struct blk_mq_alloc_data; diff --git a/include/linux/bio.h b/include/linux/bio.h index 41d417ee1349..ed746738755a 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -53,11 +53,7 @@ static inline unsigned int bio_max_segs(unsigned int nr_segs) */ static inline bool bio_has_data(struct bio *bio) { - if (bio && - bio->bi_iter.bi_size && - bio_op(bio) != REQ_OP_DISCARD && - bio_op(bio) != REQ_OP_SECURE_ERASE && - bio_op(bio) != REQ_OP_WRITE_ZEROES) + if (bio && (bio_op(bio) == REQ_OP_READ || bio_op(bio) == REQ_OP_WRITE)) return true; return false; diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index d5c5e59ddbd2..78624e8f4ab4 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -393,6 +393,10 @@ enum req_op { /* reset all the zone present on the device */ REQ_OP_ZONE_RESET_ALL = (__force blk_opf_t)17, + /* copy offload dst and src operation */ + REQ_OP_COPY_SRC = (__force blk_opf_t)19, + REQ_OP_COPY_DST = (__force blk_opf_t)21, + /* Driver private requests */ REQ_OP_DRV_IN = (__force blk_opf_t)34, REQ_OP_DRV_OUT = (__force blk_opf_t)35, @@ -481,6 +485,12 @@ static inline bool op_is_write(blk_opf_t op) return !!(op & (__force blk_opf_t)1); } +static inline bool op_is_copy(blk_opf_t op) +{ + return ((op & REQ_OP_MASK) == REQ_OP_COPY_SRC || + (op & REQ_OP_MASK) == REQ_OP_COPY_DST); +} + /* * Check if the bio or request is one that needs special treatment in the * flush state machine.