* [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O @ 2026-10-26 4:16 M Nikhil 2026-10-26 4:16 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 2026-10-26 4:16 ` [PATCH v13 2/2] zfcp: Use DMA streaming API to map I/O M Nikhil 0 siblings, 2 replies; 12+ messages in thread From: M Nikhil @ 2026-10-26 4:16 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock In the existing zFCP driver, virtual addresses are translated directly into bus (physical addresses) for DMA operations on all I/O buffers passing from zFCP driver to the device. Need for using DMA-API in zFCP driver: In a Secure Execution environment, the host must ensure that device DMA accesses are restricted to non-guest-private, page-sized memory blocks. This prevents I/O failures that can occur when a device attempts to access guest-private memory. Therefore, guest memory pages must be prepared by the hypervisor before they become accessible to an I/O device. To support this requirement, the host Linux kernel must be reliably informed whenever a memory region becomes eligible for device DMA access and when that access must be revoked. This information must be maintained correctly at least at page size granularity. To satisfy these requirements, all I/O buffers used by the zFCP driver should be mapped through the DMA API. DMA API Integration in zFCP: The zFCP driver is updated to use the DMA streaming API's to map all the I/O buffers which will be passed to the device. All zFCP I/O buffers (QTCB, SRB, CT/ELS and SCSI I/O) are represented as scatter-gather lists and mapped through DMA API using dma_map_sgtable(). Once the DMA transfer is complete, the corresponding mappings are released using dma_unmap_sgtable(). By routing all device-visible memory through the DMA mapping layer, the driver ensures that: 1. DMA access is properly authorized before use. 2. DMA is revoked after use. 3. Secure Execution memory restrictions are honored. M Nikhil (2): zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure zfcp: Use DMA streaming API to map I/O drivers/s390/scsi/zfcp_aux.c | 16 ++ drivers/s390/scsi/zfcp_dbf.c | 16 +- drivers/s390/scsi/zfcp_def.h | 4 + drivers/s390/scsi/zfcp_ext.h | 12 +- drivers/s390/scsi/zfcp_fc.c | 48 +++-- drivers/s390/scsi/zfcp_fsf.c | 325 +++++++++++++++++++++++++++++----- drivers/s390/scsi/zfcp_fsf.h | 9 +- drivers/s390/scsi/zfcp_qdio.c | 40 +++-- drivers/s390/scsi/zfcp_qdio.h | 27 +-- drivers/s390/scsi/zfcp_scsi.c | 126 ++++++++++++- 10 files changed, 518 insertions(+), 105 deletions(-) -- 2.53.0 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-26 4:16 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil @ 2026-10-26 4:16 ` M Nikhil 2026-10-26 9:08 ` sashiko-bot 2026-10-26 4:16 ` [PATCH v13 2/2] zfcp: Use DMA streaming API to map I/O M Nikhil 1 sibling, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-26 4:16 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock The zfcp_fsf_ct_els data structure is updated to replace the sg_req and sg_resp members, which are of type struct scatterlist, with request and response sg_table instances. These sg_table structure reference the corresponding scatterlists (sg_req and sg_resp) maintained in struct zfcp_fc_req. These changes allows to track the original and mapped scatterlist nents once zfcp is converted to use DMA-API for mapping the sg lists. Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Nihar Panda <niharp@linux.ibm.com> --- drivers/s390/scsi/zfcp_dbf.c | 16 ++++++++-------- drivers/s390/scsi/zfcp_fc.c | 36 ++++++++++++++++++++++++------------ drivers/s390/scsi/zfcp_fsf.c | 6 ++++-- drivers/s390/scsi/zfcp_fsf.h | 9 +++++---- 4 files changed, 41 insertions(+), 26 deletions(-) diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c index 81fb8af408e9..f7e737e076bf 100644 --- a/drivers/s390/scsi/zfcp_dbf.c +++ b/drivers/s390/scsi/zfcp_dbf.c @@ -617,9 +617,9 @@ void zfcp_dbf_san_req(char *tag, struct zfcp_fsf_req *fsf, u32 d_id) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->req); - zfcp_dbf_san(tag, dbf, "san_req", ct_els->req, ZFCP_DBF_SAN_REQ, - length, fsf->req_id, d_id, length); + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_req.sgl); + zfcp_dbf_san(tag, dbf, "san_req", ct_els->sgt_req.sgl, + ZFCP_DBF_SAN_REQ, length, fsf->req_id, d_id, length); } static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, @@ -627,9 +627,9 @@ static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, u16 len) { struct zfcp_fsf_ct_els *ct_els = fsf->data; - struct fc_ct_hdr *reqh = sg_virt(ct_els->req); + struct fc_ct_hdr *reqh = sg_virt(ct_els->sgt_req.sgl); struct fc_ns_gid_ft *reqn = (struct fc_ns_gid_ft *)(reqh + 1); - struct scatterlist *resp_entry = ct_els->resp; + struct scatterlist *resp_entry = ct_els->sgt_resp.sgl; struct fc_ct_hdr *resph; struct fc_gpn_ft_resp *acc; int max_entries, x, last = 0; @@ -698,9 +698,9 @@ void zfcp_dbf_san_res(char *tag, struct zfcp_fsf_req *fsf) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->resp); - zfcp_dbf_san(tag, dbf, "san_res", ct_els->resp, ZFCP_DBF_SAN_RES, - length, fsf->req_id, ct_els->d_id, + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_resp.sgl); + zfcp_dbf_san(tag, dbf, "san_res", ct_els->sgt_resp.sgl, + ZFCP_DBF_SAN_RES, length, fsf->req_id, ct_els->d_id, zfcp_dbf_san_res_cap_len_if_gpn_ft(tag, fsf, length)); } diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index 05d081297879..1fb6f2c3b607 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -393,10 +393,12 @@ static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port, fc_req->ct_els.port = port; fc_req->ct_els.handler = zfcp_fc_complete; fc_req->ct_els.handler_data = &completion; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req)); sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr, FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE); @@ -558,12 +560,14 @@ static int zfcp_fc_adisc(struct zfcp_port *port) return -ENOMEM; fc_req->ct_els.port = port; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req, sizeof(struct fc_els_adisc)); sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp, sizeof(struct fc_els_adisc)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); fc_req->ct_els.handler = zfcp_fc_adisc_handler; fc_req->ct_els.handler_data = fc_req; @@ -706,8 +710,10 @@ static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -865,8 +871,10 @@ static int zfcp_fc_gspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -924,8 +932,10 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -1090,8 +1100,10 @@ int zfcp_fc_exec_bsg_job(struct bsg_job *job) if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN)) return -EINVAL; - ct_els->req = job->request_payload.sg_list; - ct_els->resp = job->reply_payload.sg_list; + ct_els->sgt_req.sgl = job->request_payload.sg_list; + ct_els->sgt_resp.sgl = job->reply_payload.sg_list; + ct_els->sgt_req.orig_nents = sg_nents(ct_els->sgt_req.sgl); + ct_els->sgt_resp.orig_nents = sg_nents(ct_els->sgt_resp.sgl); ct_els->handler_data = job; switch (bsg_request->msgcode) { diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c index d407f16e77ef..a3b99839da9e 100644 --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -1242,7 +1242,8 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port, } req->status |= ZFCP_STATUS_FSFREQ_CLEANUP; - ret = zfcp_fsf_setup_ct_els(req, ct->req, ct->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, ct->sgt_req.sgl, ct->sgt_resp.sgl, + timeout); if (ret) goto failed_send; @@ -1342,7 +1343,8 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id, if (!zfcp_adapter_multi_buffer_active(adapter)) zfcp_qdio_sbal_limit(qdio, &req->qdio_req, 2); - ret = zfcp_fsf_setup_ct_els(req, els->req, els->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, els->sgt_req.sgl, els->sgt_resp.sgl, + timeout); if (ret) goto failed_send; diff --git a/drivers/s390/scsi/zfcp_fsf.h b/drivers/s390/scsi/zfcp_fsf.h index 4b92e85ec71d..22e7fd933a78 100644 --- a/drivers/s390/scsi/zfcp_fsf.h +++ b/drivers/s390/scsi/zfcp_fsf.h @@ -487,8 +487,9 @@ struct zfcp_blk_drv_data { /** * struct zfcp_fsf_ct_els - zfcp data for ct or els request - * @req: scatter-gather list for request, points to &zfcp_fc_req.sg_req or BSG - * @resp: scatter-gather list for response, points to &zfcp_fc_req.sg_rsp or BSG + * @sgt_req: sg_table for request, its sgl points to &zfcp_fc_req.sg_req or BSG + * @sgt_resp: sg_table for response, its sgl points to &zfcp_fc_req.sg_resp + * or BSG * @handler: handler function (called for response to the request) * @handler_data: data passed to handler function * @port: Optional pointer to port for zfcp internal ELS (only test link ADISC) @@ -496,8 +497,8 @@ struct zfcp_blk_drv_data { * @d_id: Destination ID of either open WKA port for CT or of D_ID for ELS */ struct zfcp_fsf_ct_els { - struct scatterlist *req; - struct scatterlist *resp; + struct sg_table sgt_req; + struct sg_table sgt_resp; void (*handler)(void *); void *handler_data; struct zfcp_port *port; -- 2.53.0 ^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-26 4:16 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil @ 2026-10-26 9:08 ` sashiko-bot 0 siblings, 0 replies; 12+ messages in thread From: sashiko-bot @ 2026-10-26 9:08 UTC (permalink / raw) To: M Nikhil, linux-s390 Cc: Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Christian Borntraeger > The zfcp_fsf_ct_els data structure is updated to replace the sg_req and > sg_resp members, which are of type struct scatterlist, with request and > response sg_table instances. > > These sg_table structure reference the corresponding scatterlists > (sg_req and sg_resp) maintained in struct zfcp_fc_req. > > These changes allows to track the original and mapped scatterlist nents > once zfcp is converted to use DMA-API for mapping the sg lists. > > Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Sashiko has reviewed this patch and found no issues. -- Sashiko AI review · https://sashiko.dev/#/patchset/20261026041654.2301619-1-nikh1092@linux.ibm.com?part=1 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 2/2] zfcp: Use DMA streaming API to map I/O 2026-10-26 4:16 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil 2026-10-26 4:16 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil @ 2026-10-26 4:16 ` M Nikhil 1 sibling, 0 replies; 12+ messages in thread From: M Nikhil @ 2026-10-26 4:16 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock In the existing zFCP driver, virtual addresses are translated directly into bus (physical) addresses for DMA operations on all I/O buffers passed from the zFCP driver to the device. Need for DMA API: In secure execution environment, the host must ensure that device DMA addresses are restricted to non-guest-private, page-sized memory blocks. This prevents I/O failures that can occur when a device attempts to access guest-private memory. Therefore, guest memory pages must be prepared by the hypervisor before they become accessible to an I/O device. To support this requirement, the host linux kernel must be reliably informed whenever a memory region becomes eligible for device DMA access and when that access must be revoked. This information must be maintained correctly at least at page level granularity. To satisfy these requirements, all I/O buffers used by the zFCP driver should be mapped through the DMA API. DMA streaming API usage in zFCP: Changes in this patch-series converts all I/O buffer mappings in the zFCP driver to use the DMA streaming API. Specifically, `dma_map_sgtable()` and `dma_unmap_sgtable()` are used to map and unmap the scatter-gather lists. All zFCP I/O buffers (QTCB, SRB, CT/ELS and SCSI I/O) are represented using scatter-gather lists. The `sg_table` structure, which encapsulates the scatterlist together with the original and mapped entry counts, is used to manage DMA mappings efficiently. Use struct sg_table to manage scatter-gather lists for QTCB, SRB, CT/ELS, and SCSI I/O buffers. Initialize single-entry scatterlists for buffers that are not already represented by scatter-gather tables. For SCSI I/O, reuse the tables provided by the SCSI midlayer and temporarily adjust orig_nents when fewer entries are populated than allocated. Map buffers after updating their contents. For SCSI I/O, synchronize req->qtcb for device access in zfcp_fsf_fcp_cmnd() before submitting the request to QDIO. DMA unmapping handles synchronization for CPU access on the receive path. Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Nihar Panda <niharp@linux.ibm.com> --- drivers/s390/scsi/zfcp_aux.c | 16 ++ drivers/s390/scsi/zfcp_def.h | 4 + drivers/s390/scsi/zfcp_ext.h | 12 +- drivers/s390/scsi/zfcp_fc.c | 12 ++ drivers/s390/scsi/zfcp_fsf.c | 325 +++++++++++++++++++++++++++++----- drivers/s390/scsi/zfcp_qdio.c | 40 +++-- drivers/s390/scsi/zfcp_qdio.h | 27 +-- drivers/s390/scsi/zfcp_scsi.c | 126 ++++++++++++- 8 files changed, 480 insertions(+), 82 deletions(-) diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c index fea573e00f9d..20c905c68e1e 100644 --- a/drivers/s390/scsi/zfcp_aux.c +++ b/drivers/s390/scsi/zfcp_aux.c @@ -329,6 +329,19 @@ static void zfcp_destroy_adapter_work_queue(struct zfcp_adapter *adapter) } +static int zfcp_set_dma_mask_for_adapter(struct zfcp_adapter *adapter) +{ + int ret; + + ret = dma_set_mask_and_coherent(&adapter->ccw_device->dev, + DMA_BIT_MASK(64)); + if (ret) + dev_err(&adapter->ccw_device->dev, + "Setting the DMA mask failed for the FCP device.\n"); + + return ret; +} + /** * zfcp_adapter_enqueue - enqueue a new adapter to the list * @ccw_device: pointer to the struct cc_device @@ -404,6 +417,9 @@ struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device) rwlock_init(&adapter->erp_lock); rwlock_init(&adapter->abort_lock); + if (zfcp_set_dma_mask_for_adapter(adapter)) + goto failed; + if (zfcp_erp_thread_setup(adapter)) goto failed; diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h index 6c761299a22f..5063921e8d93 100644 --- a/drivers/s390/scsi/zfcp_def.h +++ b/drivers/s390/scsi/zfcp_def.h @@ -322,6 +322,8 @@ static inline u64 zfcp_scsi_dev_lun(struct scsi_device *sdev) * @pool: reference to memory pool if used for this request * @issued: time when request was send (STCK) * @handler: handler which should be called to process response + * @metadata_sgt: sg_table for metadata of a QTCB or SRB request + * @metadata_sg: scatterlist for metadata of a QTCB or SRB request */ struct zfcp_fsf_req { struct list_head list; @@ -337,6 +339,8 @@ struct zfcp_fsf_req { mempool_t *pool; unsigned long long issued; void (*handler)(struct zfcp_fsf_req *); + struct sg_table metadata_sgt; + struct scatterlist metadata_sg; }; static inline diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h index 0eb9bc9d03e4..046de5aac997 100644 --- a/drivers/s390/scsi/zfcp_ext.h +++ b/drivers/s390/scsi/zfcp_ext.h @@ -141,6 +141,7 @@ extern void zfcp_fsf_req_free(struct zfcp_fsf_req *); extern void zfcp_fsf_fc_host_link_down(struct zfcp_adapter *adapter); extern struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_device *sdev, u8 tm_flags); +void zfcp_fsf_fcp_task_mgmt_handler(struct zfcp_fsf_req *req); extern struct zfcp_fsf_req *zfcp_fsf_abort_fcp_cmnd(struct scsi_cmnd *); extern void zfcp_fsf_reqid_check(struct zfcp_qdio *, int); enum zfcp_fsf_print_fmt { @@ -150,6 +151,11 @@ enum zfcp_fsf_print_fmt { extern ssize_t zfcp_fsf_scnprint_fc_security(char *buf, size_t size, u32 fc_security, enum zfcp_fsf_print_fmt fmt); +int zfcp_fsf_req_map_sg(struct zfcp_fsf_req *req, struct sg_table *sgt, + enum dma_data_direction dma_dir); +void zfcp_fsf_req_unmap_sg(struct device *dev, + struct sg_table *sgt, + enum dma_data_direction dma_dir); /* zfcp_qdio.c */ extern int zfcp_qdio_setup(struct zfcp_adapter *); @@ -157,13 +163,15 @@ extern void zfcp_qdio_destroy(struct zfcp_qdio *); extern int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio) __must_hold(qdio->req_q_lock); extern int zfcp_qdio_send(struct zfcp_qdio *, struct zfcp_qdio_req *); -extern int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *, struct zfcp_qdio_req *, - struct scatterlist *); +int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct sg_table *sgt, + struct zfcp_fsf_req *req, + enum dma_data_direction dma_dir); extern void zfcp_qdio_shost_update(struct zfcp_adapter *const adapter, const struct zfcp_qdio *const qdio); extern int zfcp_qdio_open(struct zfcp_qdio *); extern void zfcp_qdio_close(struct zfcp_qdio *); extern void zfcp_qdio_siosl(struct zfcp_adapter *); +void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt); /* zfcp_scsi.c */ extern bool zfcp_experimental_dix; diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index 1fb6f2c3b607..bc8dfdebe88f 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -1104,6 +1104,18 @@ int zfcp_fc_exec_bsg_job(struct bsg_job *job) ct_els->sgt_resp.sgl = job->reply_payload.sg_list; ct_els->sgt_req.orig_nents = sg_nents(ct_els->sgt_req.sgl); ct_els->sgt_resp.orig_nents = sg_nents(ct_els->sgt_resp.sgl); + /* + * dd_data lives past the memset(job, 0, sizeof(*job)) boundary in + * bsg_transport_sg_io_fn() and is never zeroed by blk-mq on request + * reuse. A prior BSG command will have left sgt->nents set to the + * mapped entry count from dma_map_sgtable(). zfcp_fsf_req_map_sg() + * treats any non-zero nents as a SCSI-midlayer "populated < allocated" + * hint and clamps orig_nents to it, causing truncated DMA mappings for + * larger follow-on payloads. Reset nents so these sg_tables are + * handled like zFCP-internal ones (nents == 0 before mapping). + */ + ct_els->sgt_req.nents = 0; + ct_els->sgt_resp.nents = 0; ct_els->handler_data = job; switch (bsg_request->msgcode) { diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c index a3b99839da9e..7e7cc3ec2090 100644 --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -14,6 +14,7 @@ #include <linux/types.h> #include <linux/slab.h> #include <scsi/fc/fc_els.h> +#include <linux/dma-mapping.h> #include "zfcp_ext.h" #include "zfcp_fc.h" #include "zfcp_dbf.h" @@ -84,6 +85,88 @@ static void zfcp_fsf_class_not_supp(struct zfcp_fsf_req *req) req->status |= ZFCP_STATUS_FSFREQ_ERROR; } +/** + * zfcp_fsf_req_map_sg - map the scattergather list for DMA transfer + * @req: pointer to zfcp_fsf_req + * @sgt: pointer to scattergather list table + * @dma_dir: DMA data direction + * Returns: 0 on success, -EIO otherwise + */ +int zfcp_fsf_req_map_sg(struct zfcp_fsf_req *req, struct sg_table *sgt, + enum dma_data_direction dma_dir) +{ + unsigned int saved_orig_nents; + int ret; + + if (!valid_dma_direction(dma_dir)) + return sgt->orig_nents ? -EIO : 0; + + if (!sgt->orig_nents) + return 0; + + /* + * The SCSI midlayer sets orig_nents to the allocated SG capacity and + * nents to the actually populated entry count (nents <= orig_nents). + * dma_map_sgtable() and dma_unmap_sgtable() both use orig_nents, so + * clamp it to the populated count to avoid mapping trailing zero-length + * entries. Only clamp when nents has been explicitly set (nents > 0); + * zFCP-internal sg_tables leave nents = 0 before mapping, relying + * solely on orig_nents. + */ + saved_orig_nents = sgt->orig_nents; + if (sgt->nents > 0 && sgt->nents < sgt->orig_nents) + sgt->orig_nents = sgt->nents; + + ret = dma_map_sgtable(&req->adapter->ccw_device->dev, sgt, dma_dir, 0); + + sgt->orig_nents = saved_orig_nents; + + return ret; +} + +/** + * zfcp_fsf_req_unmap_sg - unmap the scattergather list after DMA transfer + * @dev: pointer to the device used for DMA + * @sgt: pointer to scattergather list table + * @dma_dir: DMA direction of the sg + */ +void zfcp_fsf_req_unmap_sg(struct device *dev, struct sg_table *sgt, + enum dma_data_direction dma_dir) +{ + unsigned int saved_orig_nents; + + /* + * We still need the check for mapped sg count here to not perform + * unmap for SCSI commands which have zero payload. + */ + if (!sgt->nents) + return; + + saved_orig_nents = sgt->orig_nents; + if (sgt->nents < sgt->orig_nents) + sgt->orig_nents = sgt->nents; + + dma_unmap_sgtable(dev, sgt, dma_dir, 0); + + sgt->orig_nents = saved_orig_nents; +} + +/** + * zfcp_fsf_req_unmap_metadata - unmap the metadata associated with FSF req + * @req: pointer to zfcp_fsf_req + */ +static inline +void zfcp_fsf_req_unmap_metadata(struct zfcp_fsf_req *const req) +{ + struct device *dev = &req->adapter->ccw_device->dev; + + if (unlikely(zfcp_fsf_req_is_status_read_buffer(req))) + zfcp_fsf_req_unmap_sg(dev, &req->metadata_sgt, DMA_FROM_DEVICE); + else + zfcp_fsf_req_unmap_sg(dev, &req->metadata_sgt, + DMA_BIDIRECTIONAL); +} + /** * zfcp_fsf_req_free - free memory used by fsf request * @req: pointer to struct zfcp_fsf_req @@ -259,6 +342,8 @@ static void zfcp_fsf_status_read_handler(struct zfcp_fsf_req *req) struct zfcp_adapter *adapter = req->adapter; struct fsf_status_read_buffer *sr_buf = req->data; + zfcp_fsf_req_unmap_metadata(req); + if (req->status & ZFCP_STATUS_FSFREQ_DISMISSED) { zfcp_dbf_hba_fsf_uss("fssrh_1", req); mempool_free(virt_to_page(sr_buf), adapter->pool.sr_data); @@ -457,6 +542,7 @@ static void zfcp_fsf_req_complete(struct zfcp_fsf_req *req) return; } + zfcp_fsf_req_unmap_metadata(req); timer_delete_sync(&req->timer); zfcp_fsf_protstatus_eval(req); zfcp_fsf_fsfstatus_eval(req); @@ -870,10 +956,27 @@ static struct zfcp_fsf_req *zfcp_fsf_req_create(struct zfcp_qdio *qdio, req->qtcb->prefix.qtcb_version = FSF_QTCB_CURRENT_VERSION; req->qtcb->header.req_handle = req->req_id; req->qtcb->header.fsf_command = fsf_cmd; - } - zfcp_qdio_req_init(adapter->qdio, &req->qdio_req, req->req_id, sbtype, - req->qtcb, sizeof(struct fsf_qtcb)); + sg_init_one(&req->metadata_sg, req->qtcb, + sizeof(struct fsf_qtcb)); + req->metadata_sgt.sgl = &req->metadata_sg; + req->metadata_sgt.orig_nents = 1; + + if (zfcp_fsf_req_map_sg(req, &req->metadata_sgt, + DMA_BIDIRECTIONAL)) { + zfcp_fsf_req_free(req); + return ERR_PTR(-EIO); + } + + zfcp_qdio_req_init(adapter->qdio, &req->qdio_req, req->req_id, + sbtype, true, + sg_dma_len(req->metadata_sgt.sgl), + sg_dma_address(req->metadata_sgt.sgl)); + } else { + /* SRB */ + zfcp_qdio_req_init(adapter->qdio, &req->qdio_req, req->req_id, + sbtype, false, 0, 0); + } return req; } @@ -885,6 +988,15 @@ static int zfcp_fsf_req_send(struct zfcp_fsf_req *req) struct zfcp_qdio *qdio = adapter->qdio; u64 req_id = req->req_id; + /* + * Flush all CPU-side QTCB writes to the SWIOTLB bounce buffer now + * that the QTCB is fully populated. SRBs carry no outbound QTCB. + */ + if (!is_srb) + dma_sync_sgtable_for_device(&adapter->ccw_device->dev, + &req->metadata_sgt, + DMA_BIDIRECTIONAL); + zfcp_reqlist_add(adapter->req_list, req); req->qdio_req.qdio_outb_usage = atomic_read(&qdio->req_q_free); @@ -954,7 +1066,17 @@ int zfcp_fsf_status_read(struct zfcp_qdio *qdio) memset(sr_buf, 0, sizeof(*sr_buf)); req->data = sr_buf; - zfcp_qdio_fill_next(qdio, &req->qdio_req, sr_buf, sizeof(*sr_buf)); + sg_init_one(&req->metadata_sg, sr_buf, sizeof(*sr_buf)); + req->metadata_sgt.sgl = &req->metadata_sg; + req->metadata_sgt.orig_nents = 1; + + retval = zfcp_fsf_req_map_sg(req, &req->metadata_sgt, DMA_FROM_DEVICE); + if (unlikely(retval)) + goto failed_dma_map; + + zfcp_qdio_fill_next(qdio, &req->qdio_req, + sg_dma_address(req->metadata_sgt.sgl), + sg_dma_len(req->metadata_sgt.sgl)); zfcp_qdio_set_sbale_last(qdio, &req->qdio_req); retval = zfcp_fsf_req_send(req); @@ -965,6 +1087,8 @@ int zfcp_fsf_status_read(struct zfcp_qdio *qdio) goto out; failed_req_send: + zfcp_fsf_req_unmap_metadata(req); +failed_dma_map: req->data = NULL; mempool_free(virt_to_page(sr_buf), adapter->pool.sr_data); failed_buf: @@ -1076,6 +1200,7 @@ struct zfcp_fsf_req *zfcp_fsf_abort_fcp_cmnd(struct scsi_cmnd *scmnd) } out_error_free: + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); req = NULL; out: @@ -1091,6 +1216,11 @@ static void zfcp_fsf_send_ct_handler(struct zfcp_fsf_req *req) ct->status = -EINVAL; + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &ct->sgt_req, DMA_TO_DEVICE); + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &ct->sgt_resp, DMA_FROM_DEVICE); + if (req->status & ZFCP_STATUS_FSFREQ_ERROR) goto skip_fsfstatus; @@ -1130,19 +1260,42 @@ static void zfcp_fsf_send_ct_handler(struct zfcp_fsf_req *req) ct->handler(ct->handler_data); } -static void zfcp_fsf_setup_ct_els_unchained(struct zfcp_qdio *qdio, - struct zfcp_qdio_req *q_req, - struct scatterlist *sg_req, - struct scatterlist *sg_resp) +static int zfcp_fsf_setup_ct_els_unchained(struct zfcp_fsf_req *req, + struct zfcp_qdio *qdio, + struct sg_table *sg_req_table, + struct sg_table *sg_resp_table) { - zfcp_qdio_fill_next(qdio, q_req, sg_virt(sg_req), sg_req->length); - zfcp_qdio_fill_next(qdio, q_req, sg_virt(sg_resp), sg_resp->length); - zfcp_qdio_set_sbale_last(qdio, q_req); + int retval = 0; + + retval = zfcp_fsf_req_map_sg(req, sg_req_table, DMA_TO_DEVICE); + if (unlikely(retval)) + goto err; + + retval = zfcp_fsf_req_map_sg(req, sg_resp_table, + DMA_FROM_DEVICE); + if (unlikely(retval)) + goto err_unmap; + + zfcp_qdio_fill_next(qdio, &req->qdio_req, + sg_dma_address(sg_req_table->sgl), + sg_dma_len(sg_req_table->sgl)); + zfcp_qdio_fill_next(qdio, &req->qdio_req, + sg_dma_address(sg_resp_table->sgl), + sg_dma_len(sg_resp_table->sgl)); + zfcp_qdio_set_sbale_last(qdio, &req->qdio_req); + + return 0; + +err_unmap: + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + sg_req_table, DMA_TO_DEVICE); +err: + return retval; } static int zfcp_fsf_setup_ct_els_sbals(struct zfcp_fsf_req *req, - struct scatterlist *sg_req, - struct scatterlist *sg_resp) + struct sg_table *sgt_req, + struct sg_table *sgt_resp) { struct zfcp_adapter *adapter = req->adapter; struct zfcp_qdio *qdio = adapter->qdio; @@ -1150,57 +1303,73 @@ static int zfcp_fsf_setup_ct_els_sbals(struct zfcp_fsf_req *req, u32 feat = adapter->adapter_features; if (zfcp_adapter_multi_buffer_active(adapter)) { - if (zfcp_qdio_sbals_from_sg(qdio, &req->qdio_req, sg_req)) + if (zfcp_qdio_sbals_from_sg(qdio, sgt_req, req, DMA_TO_DEVICE)) return -EIO; + qtcb->bottom.support.req_buf_length = - zfcp_qdio_real_bytes(sg_req); - if (zfcp_qdio_sbals_from_sg(qdio, &req->qdio_req, sg_resp)) - return -EIO; + zfcp_qdio_real_bytes(sgt_req->sgl); + + if (zfcp_qdio_sbals_from_sg(qdio, sgt_resp, req, DMA_FROM_DEVICE)) + goto err_unmap; + qtcb->bottom.support.resp_buf_length = - zfcp_qdio_real_bytes(sg_resp); + zfcp_qdio_real_bytes(sgt_resp->sgl); - zfcp_qdio_set_data_div(qdio, &req->qdio_req, sg_nents(sg_req)); + zfcp_qdio_set_data_div(qdio, &req->qdio_req, + sgt_req->nents); zfcp_qdio_set_sbale_last(qdio, &req->qdio_req); zfcp_qdio_set_scount(qdio, &req->qdio_req); return 0; } /* use single, unchained SBAL if it can hold the request */ - if (zfcp_qdio_sg_one_sbale(sg_req) && zfcp_qdio_sg_one_sbale(sg_resp)) { - zfcp_fsf_setup_ct_els_unchained(qdio, &req->qdio_req, - sg_req, sg_resp); + if (zfcp_qdio_sg_one_sbale(sgt_req->sgl) && + zfcp_qdio_sg_one_sbale(sgt_resp->sgl)) { + if (zfcp_fsf_setup_ct_els_unchained(req, qdio, sgt_req, + sgt_resp)) + return -EIO; + return 0; } if (!(feat & FSF_FEATURE_ELS_CT_CHAINED_SBALS)) return -EOPNOTSUPP; - if (zfcp_qdio_sbals_from_sg(qdio, &req->qdio_req, sg_req)) + if (zfcp_qdio_sbals_from_sg(qdio, sgt_req, req, DMA_TO_DEVICE)) return -EIO; - qtcb->bottom.support.req_buf_length = zfcp_qdio_real_bytes(sg_req); + qtcb->bottom.support.req_buf_length = + zfcp_qdio_real_bytes(sgt_req->sgl); zfcp_qdio_set_sbale_last(qdio, &req->qdio_req); zfcp_qdio_skip_to_last_sbale(qdio, &req->qdio_req); - if (zfcp_qdio_sbals_from_sg(qdio, &req->qdio_req, sg_resp)) - return -EIO; + if (zfcp_qdio_sbals_from_sg(qdio, sgt_resp, req, DMA_FROM_DEVICE)) + goto err_unmap; - qtcb->bottom.support.resp_buf_length = zfcp_qdio_real_bytes(sg_resp); + qtcb->bottom.support.resp_buf_length = + zfcp_qdio_real_bytes(sgt_resp->sgl); zfcp_qdio_set_sbale_last(qdio, &req->qdio_req); return 0; + +err_unmap: + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + sgt_req, DMA_TO_DEVICE); + zfcp_qdio_zero_sbals(qdio->req_q, req->qdio_req.sbal_first, + req->qdio_req.sbal_number); + return -EIO; } static int zfcp_fsf_setup_ct_els(struct zfcp_fsf_req *req, - struct scatterlist *sg_req, - struct scatterlist *sg_resp, + struct sg_table *sgt_req, + struct sg_table *sgt_resp, unsigned int timeout) { int ret; - ret = zfcp_fsf_setup_ct_els_sbals(req, sg_req, sg_resp); + ret = zfcp_fsf_setup_ct_els_sbals(req, sgt_req, sgt_resp); if (ret) return ret; @@ -1242,8 +1411,7 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port, } req->status |= ZFCP_STATUS_FSFREQ_CLEANUP; - ret = zfcp_fsf_setup_ct_els(req, ct->sgt_req.sgl, ct->sgt_resp.sgl, - timeout); + ret = zfcp_fsf_setup_ct_els(req, &ct->sgt_req, &ct->sgt_resp, timeout); if (ret) goto failed_send; @@ -1256,12 +1424,21 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port, ret = zfcp_fsf_req_send(req); if (ret) - goto failed_send; + goto err_unmap; + /* NOTE: DO NOT TOUCH req PAST THIS POINT! */ goto out; +err_unmap: + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &ct->sgt_req, DMA_TO_DEVICE); + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &ct->sgt_resp, DMA_FROM_DEVICE); failed_send: + zfcp_qdio_zero_sbals(qdio->req_q, req->qdio_req.sbal_first, + req->qdio_req.sbal_number); + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); out: spin_unlock_irq(&qdio->req_q_lock); @@ -1275,6 +1452,11 @@ static void zfcp_fsf_send_els_handler(struct zfcp_fsf_req *req) send_els->status = -EINVAL; + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &send_els->sgt_req, DMA_TO_DEVICE); + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &send_els->sgt_resp, DMA_FROM_DEVICE); + if (req->status & ZFCP_STATUS_FSFREQ_ERROR) goto skip_fsfstatus; @@ -1343,9 +1525,8 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id, if (!zfcp_adapter_multi_buffer_active(adapter)) zfcp_qdio_sbal_limit(qdio, &req->qdio_req, 2); - ret = zfcp_fsf_setup_ct_els(req, els->sgt_req.sgl, els->sgt_resp.sgl, + ret = zfcp_fsf_setup_ct_els(req, &els->sgt_req, &els->sgt_resp, timeout); - if (ret) goto failed_send; @@ -1358,12 +1539,21 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id, ret = zfcp_fsf_req_send(req); if (ret) - goto failed_send; + goto err_unmap; + /* NOTE: DO NOT TOUCH req PAST THIS POINT! */ goto out; +err_unmap: + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &els->sgt_req, DMA_TO_DEVICE); + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &els->sgt_resp, DMA_FROM_DEVICE); failed_send: + zfcp_qdio_zero_sbals(qdio->req_q, req->qdio_req.sbal_first, + req->qdio_req.sbal_number); + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); out: spin_unlock_irq(&qdio->req_q_lock); @@ -1404,6 +1594,7 @@ int zfcp_fsf_exchange_config_data(struct zfcp_erp_action *erp_action) zfcp_fsf_start_erp_timer(req); retval = zfcp_fsf_req_send(req); if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); erp_action->fsf_req_id = 0; } @@ -1469,6 +1660,8 @@ int zfcp_fsf_exchange_config_data_sync(struct zfcp_qdio *qdio, retval = -EIO; else if (req->status & ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE) retval = -EAGAIN; + } else { + zfcp_fsf_req_unmap_metadata(req); } zfcp_fsf_req_free(req); @@ -1516,6 +1709,7 @@ int zfcp_fsf_exchange_port_data(struct zfcp_erp_action *erp_action) zfcp_fsf_start_erp_timer(req); retval = zfcp_fsf_req_send(req); if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); erp_action->fsf_req_id = 0; } @@ -1578,6 +1772,8 @@ int zfcp_fsf_exchange_port_data_sync(struct zfcp_qdio *qdio, retval = -EIO; else if (req->status & ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE) retval = -EAGAIN; + } else { + zfcp_fsf_req_unmap_metadata(req); } zfcp_fsf_req_free(req); @@ -1810,6 +2006,7 @@ int zfcp_fsf_open_port(struct zfcp_erp_action *erp_action) zfcp_fsf_start_erp_timer(req); retval = zfcp_fsf_req_send(req); if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); erp_action->fsf_req_id = 0; put_device(&port->dev); @@ -1876,6 +2073,7 @@ int zfcp_fsf_close_port(struct zfcp_erp_action *erp_action) zfcp_fsf_start_erp_timer(req); retval = zfcp_fsf_req_send(req); if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); erp_action->fsf_req_id = 0; } @@ -1950,8 +2148,10 @@ int zfcp_fsf_open_wka_port(struct zfcp_fc_wka_port *wka_port) zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT); retval = zfcp_fsf_req_send(req); - if (retval) + if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); + } /* NOTE: DO NOT TOUCH req PAST THIS POINT! */ out: spin_unlock_irq(&qdio->req_q_lock); @@ -2009,8 +2209,10 @@ int zfcp_fsf_close_wka_port(struct zfcp_fc_wka_port *wka_port) zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT); retval = zfcp_fsf_req_send(req); - if (retval) + if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); + } /* NOTE: DO NOT TOUCH req PAST THIS POINT! */ out: spin_unlock_irq(&qdio->req_q_lock); @@ -2103,6 +2305,7 @@ int zfcp_fsf_close_physical_port(struct zfcp_erp_action *erp_action) zfcp_fsf_start_erp_timer(req); retval = zfcp_fsf_req_send(req); if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); erp_action->fsf_req_id = 0; } @@ -2227,6 +2430,7 @@ int zfcp_fsf_open_lun(struct zfcp_erp_action *erp_action) zfcp_fsf_start_erp_timer(req); retval = zfcp_fsf_req_send(req); if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); erp_action->fsf_req_id = 0; } @@ -2316,6 +2520,7 @@ int zfcp_fsf_close_lun(struct zfcp_erp_action *erp_action) zfcp_fsf_start_erp_timer(req); retval = zfcp_fsf_req_send(req); if (retval) { + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); erp_action->fsf_req_id = 0; } @@ -2474,6 +2679,15 @@ static void zfcp_fsf_fcp_cmnd_handler(struct zfcp_fsf_req *req) return; } + if ((scsi_get_prot_op(scpnt) != SCSI_PROT_NORMAL) && + scsi_prot_sg_count(scpnt)) + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &scpnt->prot_sdb->table, + scpnt->sc_data_direction); + + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &scpnt->sdb.table, scpnt->sc_data_direction); + zfcp_fsf_fcp_handler_common(req, scpnt->device); if (unlikely(req->status & ZFCP_STATUS_FSFREQ_ERROR)) { @@ -2617,20 +2831,22 @@ int zfcp_fsf_fcp_cmnd(struct scsi_cmnd *scsi_cmnd) if ((scsi_get_prot_op(scsi_cmnd) != SCSI_PROT_NORMAL) && scsi_prot_sg_count(scsi_cmnd)) { - zfcp_qdio_set_data_div(qdio, &req->qdio_req, - scsi_prot_sg_count(scsi_cmnd)); - retval = zfcp_qdio_sbals_from_sg(qdio, &req->qdio_req, - scsi_prot_sglist(scsi_cmnd)); + retval = zfcp_qdio_sbals_from_sg(qdio, + &scsi_cmnd->prot_sdb->table, + req, + scsi_cmnd->sc_data_direction); if (retval) goto failed_scsi_cmnd; + zfcp_qdio_set_data_div(qdio, &req->qdio_req, + scsi_cmnd->prot_sdb->table.nents); io->prot_data_length = zfcp_qdio_real_bytes( scsi_prot_sglist(scsi_cmnd)); } - retval = zfcp_qdio_sbals_from_sg(qdio, &req->qdio_req, - scsi_sglist(scsi_cmnd)); + retval = zfcp_qdio_sbals_from_sg(qdio, &scsi_cmnd->sdb.table, req, + scsi_cmnd->sc_data_direction); if (unlikely(retval)) - goto failed_scsi_cmnd; + goto failed_normal_scsi_map; zfcp_qdio_set_sbale_last(adapter->qdio, &req->qdio_req); if (zfcp_adapter_multi_buffer_active(adapter)) @@ -2638,12 +2854,26 @@ int zfcp_fsf_fcp_cmnd(struct scsi_cmnd *scsi_cmnd) retval = zfcp_fsf_req_send(req); if (unlikely(retval)) - goto failed_scsi_cmnd; + goto failed_req_send; + /* NOTE: DO NOT TOUCH req PAST THIS POINT! */ goto out; +failed_req_send: + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &scsi_cmnd->sdb.table, + scsi_cmnd->sc_data_direction); +failed_normal_scsi_map: + if ((scsi_get_prot_op(scsi_cmnd) != SCSI_PROT_NORMAL) && + scsi_prot_sg_count(scsi_cmnd)) + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + &scsi_cmnd->prot_sdb->table, + scsi_cmnd->sc_data_direction); failed_scsi_cmnd: + zfcp_qdio_zero_sbals(qdio->req_q, req->qdio_req.sbal_first, + req->qdio_req.sbal_number); + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); scsi_cmnd->host_scribble = NULL; out: @@ -2651,7 +2881,7 @@ int zfcp_fsf_fcp_cmnd(struct scsi_cmnd *scsi_cmnd) return retval; } -static void zfcp_fsf_fcp_task_mgmt_handler(struct zfcp_fsf_req *req) +void zfcp_fsf_fcp_task_mgmt_handler(struct zfcp_fsf_req *req) { struct scsi_device *sdev = req->data; struct fcp_resp_with_ext *fcp_rsp; @@ -2719,6 +2949,7 @@ struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_device *sdev, goto out; } + zfcp_fsf_req_unmap_metadata(req); zfcp_fsf_req_free(req); req = NULL; out: diff --git a/drivers/s390/scsi/zfcp_qdio.c b/drivers/s390/scsi/zfcp_qdio.c index bac8385e069f..83855d2dd94a 100644 --- a/drivers/s390/scsi/zfcp_qdio.c +++ b/drivers/s390/scsi/zfcp_qdio.c @@ -39,7 +39,7 @@ static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *dbftag, ZFCP_STATUS_COMMON_ERP_FAILED, dbftag); } -static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt) +void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt) { int i, sbal_idx; @@ -233,31 +233,41 @@ zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) } /** - * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list + * zfcp_qdio_sbals_from_sg - DMA map scatter-gather list and fill SBALs from it * @qdio: pointer to struct zfcp_qdio - * @q_req: pointer to struct zfcp_qdio_req - * @sg: scatter-gather list - * Returns: zero or -EINVAL on error + * @sgt: pointer to scattergather list table + * @req: pointer to zfcp_fsf_req + * @dma_dir: DMA direction of I/O + * Returns: zero on success, -EINVAL or -EIO otherwise */ -int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, - struct scatterlist *sg) +int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct sg_table *sgt, + struct zfcp_fsf_req *req, + enum dma_data_direction dma_dir) { struct qdio_buffer_element *sbale; + int i; + struct scatterlist *sg_element; + + if (zfcp_fsf_req_map_sg(req, sgt, dma_dir)) + return -EIO; /* set storage-block type for this request */ - sbale = zfcp_qdio_sbale_req(qdio, q_req); - sbale->sflags |= q_req->sbtype; + sbale = zfcp_qdio_sbale_req(qdio, &req->qdio_req); + sbale->sflags |= req->qdio_req.sbtype; - for (; sg; sg = sg_next(sg)) { - sbale = zfcp_qdio_sbale_next(qdio, q_req); + for_each_sgtable_dma_sg(sgt, sg_element, i) { + sbale = zfcp_qdio_sbale_next(qdio, &req->qdio_req); if (!sbale) { atomic_inc(&qdio->req_q_full); - zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, - q_req->sbal_number); + zfcp_qdio_zero_sbals(qdio->req_q, + req->qdio_req.sbal_first, + req->qdio_req.sbal_number); + zfcp_fsf_req_unmap_sg(&req->adapter->ccw_device->dev, + sgt, dma_dir); return -EINVAL; } - sbale->addr = u64_to_dma64(sg_phys(sg)); - sbale->length = sg->length; + sbale->addr = u64_to_dma64(sg_dma_address(sg_element)); + sbale->length = sg_dma_len(sg_element); } return 0; } diff --git a/drivers/s390/scsi/zfcp_qdio.h b/drivers/s390/scsi/zfcp_qdio.h index 8f7d2ae94441..9f89f2975f6f 100644 --- a/drivers/s390/scsi/zfcp_qdio.h +++ b/drivers/s390/scsi/zfcp_qdio.h @@ -11,6 +11,7 @@ #define ZFCP_QDIO_H #include <linux/interrupt.h> +#include <linux/types.h> #include <asm/qdio.h> #define ZFCP_QDIO_SBALE_LEN PAGE_SIZE @@ -106,16 +107,19 @@ zfcp_qdio_sbale_curr(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) * @q_req: the qdio request to start * @req_id: The request id * @sbtype: type flags to set for all sbals - * @data: First data block - * @len: Length of first data block + * @has_qtcb: FSF request has a QTCB + * @qtcb_len: Length of first data block QTCB, if any + * @qtcb_dma_handle: DMA handle of the QTCB, if any * * This is the start of putting the request into the queue, the last * step is passing the request to zfcp_qdio_send. The request queue * lock must be held during the whole process from init to send. */ static inline -void zfcp_qdio_req_init(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, - u64 req_id, u8 sbtype, void *data, u32 len) +void zfcp_qdio_req_init(struct zfcp_qdio *qdio, + struct zfcp_qdio_req *q_req, u64 req_id, + u8 sbtype, bool has_qtcb, u32 qtcb_len, + dma_addr_t qtcb_dma_handle) { struct qdio_buffer_element *sbale; int count = min(atomic_read(&qdio->req_q_free), @@ -133,33 +137,34 @@ void zfcp_qdio_req_init(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, sbale->eflags = 0; sbale->sflags = SBAL_SFLAGS0_COMMAND | sbtype; - if (unlikely(!data)) + if (unlikely(!has_qtcb)) return; sbale++; - sbale->addr = virt_to_dma64(data); - sbale->length = len; + sbale->addr = u64_to_dma64(qtcb_dma_handle); + sbale->length = qtcb_len; } /** * zfcp_qdio_fill_next - Fill next sbale, only for single sbal requests * @qdio: pointer to struct zfcp_qdio * @q_req: pointer to struct zfcp_queue_req - * @data: pointer to data + * @dma_handle: dma address * @len: length of data * * This is only required for single sbal requests, calling it when * wrapping around to the next sbal is a bug. */ static inline -void zfcp_qdio_fill_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, - void *data, u32 len) +void zfcp_qdio_fill_next(struct zfcp_qdio *qdio, + struct zfcp_qdio_req *q_req, + dma_addr_t dma_handle, u32 len) { struct qdio_buffer_element *sbale; BUG_ON(q_req->sbale_curr == qdio->max_sbale_per_sbal - 1); q_req->sbale_curr++; sbale = zfcp_qdio_sbale_curr(qdio, q_req); - sbale->addr = virt_to_dma64(data); + sbale->addr = u64_to_dma64(dma_handle); sbale->length = len; } diff --git a/drivers/s390/scsi/zfcp_scsi.c b/drivers/s390/scsi/zfcp_scsi.c index 3590113c2b74..3b4a684cb965 100644 --- a/drivers/s390/scsi/zfcp_scsi.c +++ b/drivers/s390/scsi/zfcp_scsi.c @@ -179,11 +179,31 @@ static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt) write_lock_irqsave(&adapter->abort_lock, flags); old_req = zfcp_reqlist_find(adapter->req_list, old_reqid); - if (!old_req) { + if (!old_req || !old_req->data) { write_unlock_irqrestore(&adapter->abort_lock, flags); zfcp_dbf_scsi_abort("abrt_or", scpnt, NULL); return FAILED; /* completion could be in progress */ } + + /* + * Suppress the normal completion handler's unmap by clearing + * req->data now, under the abort_lock write-side. The actual + * DMA unmap is deferred until the hardware has stopped using + * the buffers (after wait_for_completion or after ERP has + * quiesced the adapter), so that we never call dma_unmap_sgtable + * while the FCP channel may still be writing into the pages. + * + * old_req->data is left NULL permanently and never restored. + * Restoring it while returning non-SUCCESS to scsi_eh would be + * unsafe: scsi_eh is free to call scsi_finish_command() on scpnt + * as soon as we return non-SUCCESS, freeing scpnt's scatter-gather + * tables while old_req (with data pointing at the freed scpnt) is + * still live. Any subsequent completion or ERP dismissal of + * old_req would then dereference a freed scpnt in + * zfcp_fsf_fcp_cmnd_handler() -- use-after-free and double + * scsi_done(). Leaving data = NULL means zfcp_fsf_fcp_cmnd_handler + * returns early harmlessly if old_req completes after we return. + */ old_req->data = NULL; /* don't access old fsf_req after releasing the abort_lock */ @@ -198,16 +218,55 @@ static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt) zfcp_erp_wait(adapter); ret = fc_block_scsi_eh(scpnt); if (ret) { + /* + * fc_block_scsi_eh returned FAST_IO_FAIL because + * fast_io_fail_tmo fired. This may originate from a + * per-port reopen (fc_timeout_fail_rport_io -> + * zfcp_scsi_terminate_rport_io -> + * zfcp_erp_port_forced_reopen) that closes the port + * asynchronously without shutting QDIO down or + * calling zfcp_fsf_req_dismiss_all(). + * + * Only unmap scpnt's DMA buffers if QDIO is already + * down. That is the exact precondition enforced by + * zfcp_fsf_req_dismiss_all() (BUG_ON QDIOUP) and + * guarantees the hardware is no longer using them. + * + * If QDIO is still up the hardware may still be + * writing into the buffers; we must not unmap now. + * Return FAILED so scsi_eh escalates instead of + * finishing scpnt. old_req->data stays NULL, so + * the eventual dismiss will skip the unmap (accepted + * DMA mapping leak for this path). + */ zfcp_dbf_scsi_abort("abrt_bl", scpnt, NULL); - return ret; + if (atomic_read(&adapter->status) & + ZFCP_STATUS_ADAPTER_QDIOUP) { + retval = FAILED; + return retval; + } + retval = ret; /* FAST_IO_FAIL, QDIO is down */ + goto out_unmap; } if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_RUNNING)) { + /* + * Adapter is gone; ERP shut down QDIO and dismissed + * all requests before clearing RUNNING. Safe to + * unmap now. + */ zfcp_dbf_scsi_abort("abrt_ru", scpnt, NULL); - return SUCCESS; + retval = SUCCESS; + goto out_unmap; } } if (!abrt_req) { + /* + * abrt_ar: all retries of zfcp_fsf_abort_fcp_cmnd() failed. + * The hardware may still be running the original I/O; do not + * unmap. old_req->data stays NULL so any eventual completion + * or ERP dismissal of old_req is a harmless no-op. + */ zfcp_dbf_scsi_abort("abrt_ar", scpnt, NULL); return FAILED; } @@ -219,11 +278,49 @@ static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt) else if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) dbf_tag = "abrt_nn"; else { - dbf_tag = "abrt_fa"; - retval = FAILED; + /* + * abrt_fa: the abort FSF request itself was dismissed by ERP + * (neither ABORTSUCCEEDED nor ABORTNOTNEEDED is set). We do + * not know whether the hardware has stopped the original I/O; + * do not unmap. old_req->data stays NULL. + */ + zfcp_dbf_scsi_abort("abrt_fa", scpnt, abrt_req); + zfcp_fsf_req_free(abrt_req); + return FAILED; } zfcp_dbf_scsi_abort(dbf_tag, scpnt, abrt_req); zfcp_fsf_req_free(abrt_req); + +out_unmap: + /* + * Every path that arrives here has confirmed the hardware is no + * longer using scpnt's DMA buffers: + * + * abrt_ok / abrt_nn: the adapter confirmed the abort FSF request; + * the FCP channel has stopped the original I/O. + * abrt_ru: adapter gone; ERP cleared RUNNING only after + * shutting QDIO down and calling + * zfcp_fsf_req_dismiss_all(). + * abrt_bl (QDIO down): fast_io_fail_tmo fired after a full ERP + * cycle that already shut QDIO down; the QDIO-up + * case was handled above with an early return. + * + * Paths where the hardware may still be running (abrt_ar, abrt_fa, + * abrt_bl with QDIO still up) return early without reaching here. + * old_req->data was cleared at entry and is never restored, so + * zfcp_fsf_fcp_cmnd_handler() will return early harmlessly if + * old_req completes or is dismissed after we return. + */ + if ((scsi_get_prot_op(scpnt) != SCSI_PROT_NORMAL) && + scsi_prot_sg_count(scpnt)) + zfcp_fsf_req_unmap_sg(&adapter->ccw_device->dev, + &scpnt->prot_sdb->table, + scpnt->sc_data_direction); + + zfcp_fsf_req_unmap_sg(&adapter->ccw_device->dev, + &scpnt->sdb.table, + scpnt->sc_data_direction); + return retval; } @@ -237,13 +334,17 @@ static void zfcp_scsi_forget_cmnd(struct zfcp_fsf_req *old_req, void *data) { struct zfcp_scsi_req_filter *filter = (struct zfcp_scsi_req_filter *)data; + struct scsi_cmnd *scpnt; - /* already aborted - prevent side-effects - or not a SCSI command */ + /* already aborted - prevent side-effects - or not a SCSI I/O command */ if (old_req->data == NULL || zfcp_fsf_req_is_status_read_buffer(old_req) || - old_req->qtcb->header.fsf_command != FSF_QTCB_FCP_CMND) + old_req->qtcb->header.fsf_command != FSF_QTCB_FCP_CMND || + old_req->handler == zfcp_fsf_fcp_task_mgmt_handler) return; + scpnt = old_req->data; + /* (tmf_scope == FCP_TMF_TGT_RESET || tmf_scope == FCP_TMF_LUN_RESET) */ if (old_req->qtcb->header.port_handle != filter->port_handle) return; @@ -253,6 +354,17 @@ static void zfcp_scsi_forget_cmnd(struct zfcp_fsf_req *old_req, void *data) return; zfcp_dbf_scsi_nullcmnd((struct scsi_cmnd *)old_req->data, old_req); + + if ((scsi_get_prot_op(scpnt) != SCSI_PROT_NORMAL) && + scsi_prot_sg_count(scpnt)) + zfcp_fsf_req_unmap_sg(&old_req->adapter->ccw_device->dev, + &scpnt->prot_sdb->table, + scpnt->sc_data_direction); + + zfcp_fsf_req_unmap_sg(&old_req->adapter->ccw_device->dev, + &scpnt->sdb.table, + scpnt->sc_data_direction); + old_req->data = NULL; } -- 2.53.0 ^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O @ 2026-10-26 10:12 M Nikhil 2026-10-26 10:13 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-26 10:12 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock In the existing zFCP driver, virtual addresses are translated directly into bus (physical addresses) for DMA operations on all I/O buffers passing from zFCP driver to the device. Need for using DMA-API in zFCP driver: In a Secure Execution environment, the host must ensure that device DMA accesses are restricted to non-guest-private, page-sized memory blocks. This prevents I/O failures that can occur when a device attempts to access guest-private memory. Therefore, guest memory pages must be prepared by the hypervisor before they become accessible to an I/O device. To support this requirement, the host Linux kernel must be reliably informed whenever a memory region becomes eligible for device DMA access and when that access must be revoked. This information must be maintained correctly at least at page size granularity. To satisfy these requirements, all I/O buffers used by the zFCP driver should be mapped through the DMA API. DMA API Integration in zFCP: The zFCP driver is updated to use the DMA streaming API's to map all the I/O buffers which will be passed to the device. All zFCP I/O buffers (QTCB, SRB, CT/ELS and SCSI I/O) are represented as scatter-gather lists and mapped through DMA API using dma_map_sgtable(). Once the DMA transfer is complete, the corresponding mappings are released using dma_unmap_sgtable(). By routing all device-visible memory through the DMA mapping layer, the driver ensures that: 1. DMA access is properly authorized before use. 2. DMA is revoked after use. 3. Secure Execution memory restrictions are honored. M Nikhil (2): zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure zfcp: Use DMA streaming API to map I/O drivers/s390/scsi/zfcp_aux.c | 15 ++ drivers/s390/scsi/zfcp_dbf.c | 16 +- drivers/s390/scsi/zfcp_def.h | 4 + drivers/s390/scsi/zfcp_ext.h | 12 +- drivers/s390/scsi/zfcp_fc.c | 48 +++-- drivers/s390/scsi/zfcp_fsf.c | 325 +++++++++++++++++++++++++++++----- drivers/s390/scsi/zfcp_fsf.h | 9 +- drivers/s390/scsi/zfcp_qdio.c | 40 +++-- drivers/s390/scsi/zfcp_qdio.h | 27 +-- drivers/s390/scsi/zfcp_scsi.c | 126 ++++++++++++- 10 files changed, 517 insertions(+), 105 deletions(-) -- 2.53.0 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-26 10:12 [PATCH v13 0/2] " M Nikhil @ 2026-10-26 10:13 ` M Nikhil 2026-10-26 10:44 ` sashiko-bot 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-26 10:13 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock The zfcp_fsf_ct_els data structure is updated to replace the sg_req and sg_resp members, which are of type struct scatterlist, with request and response sg_table instances. These sg_table structure reference the corresponding scatterlists (sg_req and sg_resp) maintained in struct zfcp_fc_req. These changes allows to track the original and mapped scatterlist nents once zfcp is converted to use DMA-API for mapping the sg lists. Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Nihar Panda <niharp@linux.ibm.com> --- drivers/s390/scsi/zfcp_dbf.c | 16 ++++++++-------- drivers/s390/scsi/zfcp_fc.c | 36 ++++++++++++++++++++++++------------ drivers/s390/scsi/zfcp_fsf.c | 6 ++++-- drivers/s390/scsi/zfcp_fsf.h | 9 +++++---- 4 files changed, 41 insertions(+), 26 deletions(-) diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c index 81fb8af408e9..f7e737e076bf 100644 --- a/drivers/s390/scsi/zfcp_dbf.c +++ b/drivers/s390/scsi/zfcp_dbf.c @@ -617,9 +617,9 @@ void zfcp_dbf_san_req(char *tag, struct zfcp_fsf_req *fsf, u32 d_id) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->req); - zfcp_dbf_san(tag, dbf, "san_req", ct_els->req, ZFCP_DBF_SAN_REQ, - length, fsf->req_id, d_id, length); + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_req.sgl); + zfcp_dbf_san(tag, dbf, "san_req", ct_els->sgt_req.sgl, + ZFCP_DBF_SAN_REQ, length, fsf->req_id, d_id, length); } static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, @@ -627,9 +627,9 @@ static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, u16 len) { struct zfcp_fsf_ct_els *ct_els = fsf->data; - struct fc_ct_hdr *reqh = sg_virt(ct_els->req); + struct fc_ct_hdr *reqh = sg_virt(ct_els->sgt_req.sgl); struct fc_ns_gid_ft *reqn = (struct fc_ns_gid_ft *)(reqh + 1); - struct scatterlist *resp_entry = ct_els->resp; + struct scatterlist *resp_entry = ct_els->sgt_resp.sgl; struct fc_ct_hdr *resph; struct fc_gpn_ft_resp *acc; int max_entries, x, last = 0; @@ -698,9 +698,9 @@ void zfcp_dbf_san_res(char *tag, struct zfcp_fsf_req *fsf) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->resp); - zfcp_dbf_san(tag, dbf, "san_res", ct_els->resp, ZFCP_DBF_SAN_RES, - length, fsf->req_id, ct_els->d_id, + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_resp.sgl); + zfcp_dbf_san(tag, dbf, "san_res", ct_els->sgt_resp.sgl, + ZFCP_DBF_SAN_RES, length, fsf->req_id, ct_els->d_id, zfcp_dbf_san_res_cap_len_if_gpn_ft(tag, fsf, length)); } diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index 05d081297879..1fb6f2c3b607 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -393,10 +393,12 @@ static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port, fc_req->ct_els.port = port; fc_req->ct_els.handler = zfcp_fc_complete; fc_req->ct_els.handler_data = &completion; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req)); sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr, FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE); @@ -558,12 +560,14 @@ static int zfcp_fc_adisc(struct zfcp_port *port) return -ENOMEM; fc_req->ct_els.port = port; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req, sizeof(struct fc_els_adisc)); sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp, sizeof(struct fc_els_adisc)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); fc_req->ct_els.handler = zfcp_fc_adisc_handler; fc_req->ct_els.handler_data = fc_req; @@ -706,8 +710,10 @@ static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -865,8 +871,10 @@ static int zfcp_fc_gspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -924,8 +932,10 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -1090,8 +1100,10 @@ int zfcp_fc_exec_bsg_job(struct bsg_job *job) if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN)) return -EINVAL; - ct_els->req = job->request_payload.sg_list; - ct_els->resp = job->reply_payload.sg_list; + ct_els->sgt_req.sgl = job->request_payload.sg_list; + ct_els->sgt_resp.sgl = job->reply_payload.sg_list; + ct_els->sgt_req.orig_nents = sg_nents(ct_els->sgt_req.sgl); + ct_els->sgt_resp.orig_nents = sg_nents(ct_els->sgt_resp.sgl); ct_els->handler_data = job; switch (bsg_request->msgcode) { diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c index d407f16e77ef..a3b99839da9e 100644 --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -1242,7 +1242,8 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port, } req->status |= ZFCP_STATUS_FSFREQ_CLEANUP; - ret = zfcp_fsf_setup_ct_els(req, ct->req, ct->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, ct->sgt_req.sgl, ct->sgt_resp.sgl, + timeout); if (ret) goto failed_send; @@ -1342,7 +1343,8 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id, if (!zfcp_adapter_multi_buffer_active(adapter)) zfcp_qdio_sbal_limit(qdio, &req->qdio_req, 2); - ret = zfcp_fsf_setup_ct_els(req, els->req, els->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, els->sgt_req.sgl, els->sgt_resp.sgl, + timeout); if (ret) goto failed_send; diff --git a/drivers/s390/scsi/zfcp_fsf.h b/drivers/s390/scsi/zfcp_fsf.h index 4b92e85ec71d..22e7fd933a78 100644 --- a/drivers/s390/scsi/zfcp_fsf.h +++ b/drivers/s390/scsi/zfcp_fsf.h @@ -487,8 +487,9 @@ struct zfcp_blk_drv_data { /** * struct zfcp_fsf_ct_els - zfcp data for ct or els request - * @req: scatter-gather list for request, points to &zfcp_fc_req.sg_req or BSG - * @resp: scatter-gather list for response, points to &zfcp_fc_req.sg_rsp or BSG + * @sgt_req: sg_table for request, its sgl points to &zfcp_fc_req.sg_req or BSG + * @sgt_resp: sg_table for response, its sgl points to &zfcp_fc_req.sg_resp + * or BSG * @handler: handler function (called for response to the request) * @handler_data: data passed to handler function * @port: Optional pointer to port for zfcp internal ELS (only test link ADISC) @@ -496,8 +497,8 @@ struct zfcp_blk_drv_data { * @d_id: Destination ID of either open WKA port for CT or of D_ID for ELS */ struct zfcp_fsf_ct_els { - struct scatterlist *req; - struct scatterlist *resp; + struct sg_table sgt_req; + struct sg_table sgt_resp; void (*handler)(void *); void *handler_data; struct zfcp_port *port; -- 2.53.0 ^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-26 10:13 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil @ 2026-10-26 10:44 ` sashiko-bot 0 siblings, 0 replies; 12+ messages in thread From: sashiko-bot @ 2026-10-26 10:44 UTC (permalink / raw) To: M Nikhil, linux-s390 Cc: Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Christian Borntraeger > The zfcp_fsf_ct_els data structure is updated to replace the sg_req and > sg_resp members, which are of type struct scatterlist, with request and > response sg_table instances. > > These sg_table structure reference the corresponding scatterlists > (sg_req and sg_resp) maintained in struct zfcp_fc_req. > > These changes allows to track the original and mapped scatterlist nents > once zfcp is converted to use DMA-API for mapping the sg lists. > > Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Sashiko has reviewed this patch and found no issues. -- Sashiko AI review · https://sashiko.dev/#/patchset/20261026101301.3543163-1-nikh1092@linux.ibm.com?part=1 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O @ 2026-10-23 11:40 M Nikhil 2026-10-23 11:40 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-23 11:40 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock In the existing zFCP driver, virtual addresses are translated directly into bus (physical addresses) for DMA operations on all I/O buffers passing from zFCP driver to the device. Need for using DMA-API in zFCP driver: In a Secure Execution environment, the host must ensure that device DMA accesses are restricted to non-guest-private, page-sized memory blocks. This prevents I/O failures that can occur when a device attempts to access guest-private memory. Therefore, guest memory pages must be prepared by the hypervisor before they become accessible to an I/O device. To support this requirement, the host Linux kernel must be reliably informed whenever a memory region becomes eligible for device DMA access and when that access must be revoked. This information must be maintained correctly at least at page size granularity. To satisfy these requirements, all I/O buffers used by the zFCP driver should be mapped through the DMA API. DMA API Integration in zFCP: The zFCP driver is updated to use the DMA streaming API's to map all the I/O buffers which will be passed to the device. All zFCP I/O buffers (QTCB, SRB, CT/ELS and SCSI I/O) are represented as scatter-gather lists and mapped through DMA API using dma_map_sgtable(). Once the DMA transfer is complete, the corresponding mappings are released using dma_unmap_sgtable(). By routing all device-visible memory through the DMA mapping layer, the driver ensures that: 1. DMA access is properly authorized before use. 2. DMA is revoked after use. 3. Secure Execution memory restrictions are honored. M Nikhil (2): zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure zfcp: Use DMA streaming API to map I/O drivers/s390/scsi/zfcp_aux.c | 16 ++ drivers/s390/scsi/zfcp_dbf.c | 16 +- drivers/s390/scsi/zfcp_def.h | 4 + drivers/s390/scsi/zfcp_ext.h | 12 +- drivers/s390/scsi/zfcp_fc.c | 48 +++-- drivers/s390/scsi/zfcp_fsf.c | 325 +++++++++++++++++++++++++++++----- drivers/s390/scsi/zfcp_fsf.h | 9 +- drivers/s390/scsi/zfcp_qdio.c | 40 +++-- drivers/s390/scsi/zfcp_qdio.h | 27 +-- drivers/s390/scsi/zfcp_scsi.c | 83 ++++++++- 10 files changed, 477 insertions(+), 103 deletions(-) -- 2.53.0 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-23 11:40 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil @ 2026-10-23 11:40 ` M Nikhil 2026-10-23 11:47 ` sashiko-bot 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-23 11:40 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock The zfcp_fsf_ct_els data structure is updated to replace the sg_req and sg_resp members, which are of type struct scatterlist, with request and response sg_table instances. These sg_table structure reference the corresponding scatterlists (sg_req and sg_resp) maintained in struct zfcp_fc_req. These changes allows to track the original and mapped scatterlist nents once zfcp is converted to use DMA-API for mapping the sg lists. Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Nihar Panda <niharp@linux.ibm.com> --- drivers/s390/scsi/zfcp_dbf.c | 16 ++++++++-------- drivers/s390/scsi/zfcp_fc.c | 36 ++++++++++++++++++++++++------------ drivers/s390/scsi/zfcp_fsf.c | 6 ++++-- drivers/s390/scsi/zfcp_fsf.h | 9 +++++---- 4 files changed, 41 insertions(+), 26 deletions(-) diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c index 81fb8af408e9..f7e737e076bf 100644 --- a/drivers/s390/scsi/zfcp_dbf.c +++ b/drivers/s390/scsi/zfcp_dbf.c @@ -617,9 +617,9 @@ void zfcp_dbf_san_req(char *tag, struct zfcp_fsf_req *fsf, u32 d_id) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->req); - zfcp_dbf_san(tag, dbf, "san_req", ct_els->req, ZFCP_DBF_SAN_REQ, - length, fsf->req_id, d_id, length); + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_req.sgl); + zfcp_dbf_san(tag, dbf, "san_req", ct_els->sgt_req.sgl, + ZFCP_DBF_SAN_REQ, length, fsf->req_id, d_id, length); } static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, @@ -627,9 +627,9 @@ static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, u16 len) { struct zfcp_fsf_ct_els *ct_els = fsf->data; - struct fc_ct_hdr *reqh = sg_virt(ct_els->req); + struct fc_ct_hdr *reqh = sg_virt(ct_els->sgt_req.sgl); struct fc_ns_gid_ft *reqn = (struct fc_ns_gid_ft *)(reqh + 1); - struct scatterlist *resp_entry = ct_els->resp; + struct scatterlist *resp_entry = ct_els->sgt_resp.sgl; struct fc_ct_hdr *resph; struct fc_gpn_ft_resp *acc; int max_entries, x, last = 0; @@ -698,9 +698,9 @@ void zfcp_dbf_san_res(char *tag, struct zfcp_fsf_req *fsf) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->resp); - zfcp_dbf_san(tag, dbf, "san_res", ct_els->resp, ZFCP_DBF_SAN_RES, - length, fsf->req_id, ct_els->d_id, + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_resp.sgl); + zfcp_dbf_san(tag, dbf, "san_res", ct_els->sgt_resp.sgl, + ZFCP_DBF_SAN_RES, length, fsf->req_id, ct_els->d_id, zfcp_dbf_san_res_cap_len_if_gpn_ft(tag, fsf, length)); } diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index 05d081297879..1fb6f2c3b607 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -393,10 +393,12 @@ static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port, fc_req->ct_els.port = port; fc_req->ct_els.handler = zfcp_fc_complete; fc_req->ct_els.handler_data = &completion; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req)); sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr, FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE); @@ -558,12 +560,14 @@ static int zfcp_fc_adisc(struct zfcp_port *port) return -ENOMEM; fc_req->ct_els.port = port; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req, sizeof(struct fc_els_adisc)); sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp, sizeof(struct fc_els_adisc)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); fc_req->ct_els.handler = zfcp_fc_adisc_handler; fc_req->ct_els.handler_data = fc_req; @@ -706,8 +710,10 @@ static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -865,8 +871,10 @@ static int zfcp_fc_gspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -924,8 +932,10 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -1090,8 +1100,10 @@ int zfcp_fc_exec_bsg_job(struct bsg_job *job) if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN)) return -EINVAL; - ct_els->req = job->request_payload.sg_list; - ct_els->resp = job->reply_payload.sg_list; + ct_els->sgt_req.sgl = job->request_payload.sg_list; + ct_els->sgt_resp.sgl = job->reply_payload.sg_list; + ct_els->sgt_req.orig_nents = sg_nents(ct_els->sgt_req.sgl); + ct_els->sgt_resp.orig_nents = sg_nents(ct_els->sgt_resp.sgl); ct_els->handler_data = job; switch (bsg_request->msgcode) { diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c index d407f16e77ef..a3b99839da9e 100644 --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -1242,7 +1242,8 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port, } req->status |= ZFCP_STATUS_FSFREQ_CLEANUP; - ret = zfcp_fsf_setup_ct_els(req, ct->req, ct->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, ct->sgt_req.sgl, ct->sgt_resp.sgl, + timeout); if (ret) goto failed_send; @@ -1342,7 +1343,8 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id, if (!zfcp_adapter_multi_buffer_active(adapter)) zfcp_qdio_sbal_limit(qdio, &req->qdio_req, 2); - ret = zfcp_fsf_setup_ct_els(req, els->req, els->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, els->sgt_req.sgl, els->sgt_resp.sgl, + timeout); if (ret) goto failed_send; diff --git a/drivers/s390/scsi/zfcp_fsf.h b/drivers/s390/scsi/zfcp_fsf.h index 4b92e85ec71d..22e7fd933a78 100644 --- a/drivers/s390/scsi/zfcp_fsf.h +++ b/drivers/s390/scsi/zfcp_fsf.h @@ -487,8 +487,9 @@ struct zfcp_blk_drv_data { /** * struct zfcp_fsf_ct_els - zfcp data for ct or els request - * @req: scatter-gather list for request, points to &zfcp_fc_req.sg_req or BSG - * @resp: scatter-gather list for response, points to &zfcp_fc_req.sg_rsp or BSG + * @sgt_req: sg_table for request, its sgl points to &zfcp_fc_req.sg_req or BSG + * @sgt_resp: sg_table for response, its sgl points to &zfcp_fc_req.sg_resp + * or BSG * @handler: handler function (called for response to the request) * @handler_data: data passed to handler function * @port: Optional pointer to port for zfcp internal ELS (only test link ADISC) @@ -496,8 +497,8 @@ struct zfcp_blk_drv_data { * @d_id: Destination ID of either open WKA port for CT or of D_ID for ELS */ struct zfcp_fsf_ct_els { - struct scatterlist *req; - struct scatterlist *resp; + struct sg_table sgt_req; + struct sg_table sgt_resp; void (*handler)(void *); void *handler_data; struct zfcp_port *port; -- 2.53.0 ^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-23 11:40 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil @ 2026-10-23 11:47 ` sashiko-bot 0 siblings, 0 replies; 12+ messages in thread From: sashiko-bot @ 2026-10-23 11:47 UTC (permalink / raw) To: M Nikhil, linux-s390 Cc: Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Christian Borntraeger > The zfcp_fsf_ct_els data structure is updated to replace the sg_req and > sg_resp members, which are of type struct scatterlist, with request and > response sg_table instances. > > These sg_table structure reference the corresponding scatterlists > (sg_req and sg_resp) maintained in struct zfcp_fc_req. > > These changes allows to track the original and mapped scatterlist nents > once zfcp is converted to use DMA-API for mapping the sg lists. > > Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Sashiko has reviewed this patch and found no issues. -- Sashiko AI review · https://sashiko.dev/#/patchset/20261023114046.4137557-1-nikh1092@linux.ibm.com?part=1 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O @ 2026-10-22 17:08 M Nikhil 2026-10-22 17:08 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-22 17:08 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock In the existing zFCP driver, virtual addresses are translated directly into bus (physical addresses) for DMA operations on all I/O buffers passing from zFCP driver to the device. Need for using DMA-API in zFCP driver: In a Secure Execution environment, the host must ensure that device DMA accesses are restricted to non-guest-private, page-sized memory blocks. This prevents I/O failures that can occur when a device attempts to access guest-private memory. Therefore, guest memory pages must be prepared by the hypervisor before they become accessible to an I/O device. To support this requirement, the host Linux kernel must be reliably informed whenever a memory region becomes eligible for device DMA access and when that access must be revoked. This information must be maintained correctly at least at page size granularity. To satisfy these requirements, all I/O buffers used by the zFCP driver should be mapped through the DMA API. DMA API Integration in zFCP: The zFCP driver is updated to use the DMA streaming API's to map all the I/O buffers which will be passed to the device. All zFCP I/O buffers (QTCB, SRB, CT/ELS and SCSI I/O) are represented as scatter-gather lists and mapped through DMA API using dma_map_sgtable(). Once the DMA transfer is complete, the corresponding mappings are released using dma_unmap_sgtable(). By routing all device-visible memory through the DMA mapping layer, the driver ensures that: 1. DMA access is properly authorized before use. 2. DMA is revoked after use. 3. Secure Execution memory restrictions are honored. M Nikhil (2): zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure zfcp: Use DMA streaming API to map I/O drivers/s390/scsi/zfcp_aux.c | 16 ++ drivers/s390/scsi/zfcp_dbf.c | 16 +- drivers/s390/scsi/zfcp_def.h | 4 + drivers/s390/scsi/zfcp_ext.h | 11 +- drivers/s390/scsi/zfcp_fc.c | 48 +++-- drivers/s390/scsi/zfcp_fsf.c | 323 +++++++++++++++++++++++++++++----- drivers/s390/scsi/zfcp_fsf.h | 9 +- drivers/s390/scsi/zfcp_qdio.c | 40 +++-- drivers/s390/scsi/zfcp_qdio.h | 27 +-- drivers/s390/scsi/zfcp_scsi.c | 67 ++++++- 10 files changed, 461 insertions(+), 100 deletions(-) -- 2.53.0 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-22 17:08 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil @ 2026-10-22 17:08 ` M Nikhil 2026-10-22 17:14 ` sashiko-bot 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-22 17:08 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock The zfcp_fsf_ct_els data structure is updated to replace the sg_req and sg_resp members, which are of type struct scatterlist, with request and response sg_table instances. These sg_table structure reference the corresponding scatterlists (sg_req and sg_resp) maintained in struct zfcp_fc_req. These changes allows to track the original and mapped scatterlist nents once zfcp is converted to use DMA-API for mapping the sg lists. Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Nihar Panda <niharp@linux.ibm.com> --- drivers/s390/scsi/zfcp_dbf.c | 16 ++++++++-------- drivers/s390/scsi/zfcp_fc.c | 36 ++++++++++++++++++++++++------------ drivers/s390/scsi/zfcp_fsf.c | 6 ++++-- drivers/s390/scsi/zfcp_fsf.h | 9 +++++---- 4 files changed, 41 insertions(+), 26 deletions(-) diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c index 81fb8af408e9..f7e737e076bf 100644 --- a/drivers/s390/scsi/zfcp_dbf.c +++ b/drivers/s390/scsi/zfcp_dbf.c @@ -617,9 +617,9 @@ void zfcp_dbf_san_req(char *tag, struct zfcp_fsf_req *fsf, u32 d_id) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->req); - zfcp_dbf_san(tag, dbf, "san_req", ct_els->req, ZFCP_DBF_SAN_REQ, - length, fsf->req_id, d_id, length); + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_req.sgl); + zfcp_dbf_san(tag, dbf, "san_req", ct_els->sgt_req.sgl, + ZFCP_DBF_SAN_REQ, length, fsf->req_id, d_id, length); } static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, @@ -627,9 +627,9 @@ static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, u16 len) { struct zfcp_fsf_ct_els *ct_els = fsf->data; - struct fc_ct_hdr *reqh = sg_virt(ct_els->req); + struct fc_ct_hdr *reqh = sg_virt(ct_els->sgt_req.sgl); struct fc_ns_gid_ft *reqn = (struct fc_ns_gid_ft *)(reqh + 1); - struct scatterlist *resp_entry = ct_els->resp; + struct scatterlist *resp_entry = ct_els->sgt_resp.sgl; struct fc_ct_hdr *resph; struct fc_gpn_ft_resp *acc; int max_entries, x, last = 0; @@ -698,9 +698,9 @@ void zfcp_dbf_san_res(char *tag, struct zfcp_fsf_req *fsf) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->resp); - zfcp_dbf_san(tag, dbf, "san_res", ct_els->resp, ZFCP_DBF_SAN_RES, - length, fsf->req_id, ct_els->d_id, + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_resp.sgl); + zfcp_dbf_san(tag, dbf, "san_res", ct_els->sgt_resp.sgl, + ZFCP_DBF_SAN_RES, length, fsf->req_id, ct_els->d_id, zfcp_dbf_san_res_cap_len_if_gpn_ft(tag, fsf, length)); } diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index 05d081297879..1fb6f2c3b607 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -393,10 +393,12 @@ static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port, fc_req->ct_els.port = port; fc_req->ct_els.handler = zfcp_fc_complete; fc_req->ct_els.handler_data = &completion; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req)); sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr, FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE); @@ -558,12 +560,14 @@ static int zfcp_fc_adisc(struct zfcp_port *port) return -ENOMEM; fc_req->ct_els.port = port; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req, sizeof(struct fc_els_adisc)); sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp, sizeof(struct fc_els_adisc)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); fc_req->ct_els.handler = zfcp_fc_adisc_handler; fc_req->ct_els.handler_data = fc_req; @@ -706,8 +710,10 @@ static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -865,8 +871,10 @@ static int zfcp_fc_gspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -924,8 +932,10 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -1090,8 +1100,10 @@ int zfcp_fc_exec_bsg_job(struct bsg_job *job) if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN)) return -EINVAL; - ct_els->req = job->request_payload.sg_list; - ct_els->resp = job->reply_payload.sg_list; + ct_els->sgt_req.sgl = job->request_payload.sg_list; + ct_els->sgt_resp.sgl = job->reply_payload.sg_list; + ct_els->sgt_req.orig_nents = sg_nents(ct_els->sgt_req.sgl); + ct_els->sgt_resp.orig_nents = sg_nents(ct_els->sgt_resp.sgl); ct_els->handler_data = job; switch (bsg_request->msgcode) { diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c index d407f16e77ef..a3b99839da9e 100644 --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -1242,7 +1242,8 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port, } req->status |= ZFCP_STATUS_FSFREQ_CLEANUP; - ret = zfcp_fsf_setup_ct_els(req, ct->req, ct->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, ct->sgt_req.sgl, ct->sgt_resp.sgl, + timeout); if (ret) goto failed_send; @@ -1342,7 +1343,8 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id, if (!zfcp_adapter_multi_buffer_active(adapter)) zfcp_qdio_sbal_limit(qdio, &req->qdio_req, 2); - ret = zfcp_fsf_setup_ct_els(req, els->req, els->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, els->sgt_req.sgl, els->sgt_resp.sgl, + timeout); if (ret) goto failed_send; diff --git a/drivers/s390/scsi/zfcp_fsf.h b/drivers/s390/scsi/zfcp_fsf.h index 4b92e85ec71d..22e7fd933a78 100644 --- a/drivers/s390/scsi/zfcp_fsf.h +++ b/drivers/s390/scsi/zfcp_fsf.h @@ -487,8 +487,9 @@ struct zfcp_blk_drv_data { /** * struct zfcp_fsf_ct_els - zfcp data for ct or els request - * @req: scatter-gather list for request, points to &zfcp_fc_req.sg_req or BSG - * @resp: scatter-gather list for response, points to &zfcp_fc_req.sg_rsp or BSG + * @sgt_req: sg_table for request, its sgl points to &zfcp_fc_req.sg_req or BSG + * @sgt_resp: sg_table for response, its sgl points to &zfcp_fc_req.sg_resp + * or BSG * @handler: handler function (called for response to the request) * @handler_data: data passed to handler function * @port: Optional pointer to port for zfcp internal ELS (only test link ADISC) @@ -496,8 +497,8 @@ struct zfcp_blk_drv_data { * @d_id: Destination ID of either open WKA port for CT or of D_ID for ELS */ struct zfcp_fsf_ct_els { - struct scatterlist *req; - struct scatterlist *resp; + struct sg_table sgt_req; + struct sg_table sgt_resp; void (*handler)(void *); void *handler_data; struct zfcp_port *port; -- 2.53.0 ^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-22 17:08 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil @ 2026-10-22 17:14 ` sashiko-bot 0 siblings, 0 replies; 12+ messages in thread From: sashiko-bot @ 2026-10-22 17:14 UTC (permalink / raw) To: M Nikhil, linux-s390 Cc: Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Christian Borntraeger > The zfcp_fsf_ct_els data structure is updated to replace the sg_req and > sg_resp members, which are of type struct scatterlist, with request and > response sg_table instances. > > These sg_table structure reference the corresponding scatterlists > (sg_req and sg_resp) maintained in struct zfcp_fc_req. > > These changes allows to track the original and mapped scatterlist nents > once zfcp is converted to use DMA-API for mapping the sg lists. > > Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Sashiko has reviewed this patch and found no issues. -- Sashiko AI review · https://sashiko.dev/#/patchset/20261022170828.4189701-1-nikh1092@linux.ibm.com?part=1 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O @ 2026-10-21 8:33 M Nikhil 2026-10-21 8:33 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-21 8:33 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock In the existing zFCP driver, virtual addresses are translated directly into bus (physical addresses) for DMA operations on all I/O buffers passing from zFCP driver to the device. Need for using DMA-API in zFCP driver: In a Secure Execution environment, the host must ensure that device DMA accesses are restricted to non-guest-private, page-sized memory blocks. This prevents I/O failures that can occur when a device attempts to access guest-private memory. Therefore, guest memory pages must be prepared by the hypervisor before they become accessible to an I/O device. To support this requirement, the host Linux kernel must be reliably informed whenever a memory region becomes eligible for device DMA access and when that access must be revoked. This information must be maintained correctly at least at page size granularity. To satisfy these requirements, all I/O buffers used by the zFCP driver should be mapped through the DMA API. DMA API Integration in zFCP: The zFCP driver is updated to use the DMA streaming API's to map all the I/O buffers which will be passed to the device. All zFCP I/O buffers (QTCB, SRB, CT/ELS and SCSI I/O) are represented as scatter-gather lists and mapped through DMA API using dma_map_sgtable(). Once the DMA transfer is complete, the corresponding mappings are released using dma_unmap_sgtable(). By routing all device-visible memory through the DMA mapping layer, the driver ensures that: 1. DMA access is properly authorized before use. 2. DMA is revoked after use. 3. Secure Execution memory restrictions are honored. M Nikhil (2): zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure zfcp: Use DMA streaming API to map I/O drivers/s390/scsi/zfcp_aux.c | 16 ++ drivers/s390/scsi/zfcp_dbf.c | 16 +- drivers/s390/scsi/zfcp_def.h | 4 + drivers/s390/scsi/zfcp_ext.h | 11 +- drivers/s390/scsi/zfcp_fc.c | 36 ++-- drivers/s390/scsi/zfcp_fsf.c | 299 +++++++++++++++++++++++++++++----- drivers/s390/scsi/zfcp_fsf.h | 9 +- drivers/s390/scsi/zfcp_qdio.c | 39 +++-- drivers/s390/scsi/zfcp_qdio.h | 27 +-- drivers/s390/scsi/zfcp_scsi.c | 26 +++ 10 files changed, 386 insertions(+), 97 deletions(-) -- 2.53.0 ^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-21 8:33 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil @ 2026-10-21 8:33 ` M Nikhil 2026-10-21 8:40 ` sashiko-bot 0 siblings, 1 reply; 12+ messages in thread From: M Nikhil @ 2026-10-21 8:33 UTC (permalink / raw) To: sashiko-reviews, linux-s390, linux-scsi; +Cc: niharp, pasic, bblock The zfcp_fsf_ct_els data structure is updated to replace the sg_req and sg_resp members, which are of type struct scatterlist, with request and response sg_table instances. These sg_table structure reference the corresponding scatterlists (sg_req and sg_resp) maintained in struct zfcp_fc_req. These changes allows to track the original and mapped scatterlist nents once zfcp is converted to use DMA-API for mapping the sg lists. Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Nihar Panda <niharp@linux.ibm.com> --- drivers/s390/scsi/zfcp_dbf.c | 16 ++++++++-------- drivers/s390/scsi/zfcp_fc.c | 36 ++++++++++++++++++++++++------------ drivers/s390/scsi/zfcp_fsf.c | 6 ++++-- drivers/s390/scsi/zfcp_fsf.h | 9 +++++---- 4 files changed, 41 insertions(+), 26 deletions(-) diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c index 81fb8af408e9..f7e737e076bf 100644 --- a/drivers/s390/scsi/zfcp_dbf.c +++ b/drivers/s390/scsi/zfcp_dbf.c @@ -617,9 +617,9 @@ void zfcp_dbf_san_req(char *tag, struct zfcp_fsf_req *fsf, u32 d_id) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->req); - zfcp_dbf_san(tag, dbf, "san_req", ct_els->req, ZFCP_DBF_SAN_REQ, - length, fsf->req_id, d_id, length); + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_req.sgl); + zfcp_dbf_san(tag, dbf, "san_req", ct_els->sgt_req.sgl, + ZFCP_DBF_SAN_REQ, length, fsf->req_id, d_id, length); } static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, @@ -627,9 +627,9 @@ static u16 zfcp_dbf_san_res_cap_len_if_gpn_ft(char *tag, u16 len) { struct zfcp_fsf_ct_els *ct_els = fsf->data; - struct fc_ct_hdr *reqh = sg_virt(ct_els->req); + struct fc_ct_hdr *reqh = sg_virt(ct_els->sgt_req.sgl); struct fc_ns_gid_ft *reqn = (struct fc_ns_gid_ft *)(reqh + 1); - struct scatterlist *resp_entry = ct_els->resp; + struct scatterlist *resp_entry = ct_els->sgt_resp.sgl; struct fc_ct_hdr *resph; struct fc_gpn_ft_resp *acc; int max_entries, x, last = 0; @@ -698,9 +698,9 @@ void zfcp_dbf_san_res(char *tag, struct zfcp_fsf_req *fsf) if (unlikely(!debug_level_enabled(dbf->san, ZFCP_DBF_SAN_LEVEL))) return; - length = (u16)zfcp_qdio_real_bytes(ct_els->resp); - zfcp_dbf_san(tag, dbf, "san_res", ct_els->resp, ZFCP_DBF_SAN_RES, - length, fsf->req_id, ct_els->d_id, + length = (u16)zfcp_qdio_real_bytes(ct_els->sgt_resp.sgl); + zfcp_dbf_san(tag, dbf, "san_res", ct_els->sgt_resp.sgl, + ZFCP_DBF_SAN_RES, length, fsf->req_id, ct_els->d_id, zfcp_dbf_san_res_cap_len_if_gpn_ft(tag, fsf, length)); } diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index 05d081297879..1fb6f2c3b607 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -393,10 +393,12 @@ static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port, fc_req->ct_els.port = port; fc_req->ct_els.handler = zfcp_fc_complete; fc_req->ct_els.handler_data = &completion; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req)); sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr, FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE); @@ -558,12 +560,14 @@ static int zfcp_fc_adisc(struct zfcp_port *port) return -ENOMEM; fc_req->ct_els.port = port; - fc_req->ct_els.req = &fc_req->sg_req; - fc_req->ct_els.resp = &fc_req->sg_rsp; + fc_req->ct_els.sgt_req.sgl = &fc_req->sg_req; + fc_req->ct_els.sgt_resp.sgl = &fc_req->sg_rsp; sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req, sizeof(struct fc_els_adisc)); sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp, sizeof(struct fc_els_adisc)); + fc_req->ct_els.sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + fc_req->ct_els.sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); fc_req->ct_els.handler = zfcp_fc_adisc_handler; fc_req->ct_els.handler_data = fc_req; @@ -706,8 +710,10 @@ static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -865,8 +871,10 @@ static int zfcp_fc_gspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -924,8 +932,10 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter, ct_els->handler = zfcp_fc_complete; ct_els->handler_data = &completion; - ct_els->req = &fc_req->sg_req; - ct_els->resp = &fc_req->sg_rsp; + ct_els->sgt_req.sgl = &fc_req->sg_req; + ct_els->sgt_resp.sgl = &fc_req->sg_rsp; + ct_els->sgt_req.orig_nents = sg_nents(&fc_req->sg_req); + ct_els->sgt_resp.orig_nents = sg_nents(&fc_req->sg_rsp); ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL, ZFCP_FC_CTELS_TMO); @@ -1090,8 +1100,10 @@ int zfcp_fc_exec_bsg_job(struct bsg_job *job) if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN)) return -EINVAL; - ct_els->req = job->request_payload.sg_list; - ct_els->resp = job->reply_payload.sg_list; + ct_els->sgt_req.sgl = job->request_payload.sg_list; + ct_els->sgt_resp.sgl = job->reply_payload.sg_list; + ct_els->sgt_req.orig_nents = sg_nents(ct_els->sgt_req.sgl); + ct_els->sgt_resp.orig_nents = sg_nents(ct_els->sgt_resp.sgl); ct_els->handler_data = job; switch (bsg_request->msgcode) { diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c index d407f16e77ef..a3b99839da9e 100644 --- a/drivers/s390/scsi/zfcp_fsf.c +++ b/drivers/s390/scsi/zfcp_fsf.c @@ -1242,7 +1242,8 @@ int zfcp_fsf_send_ct(struct zfcp_fc_wka_port *wka_port, } req->status |= ZFCP_STATUS_FSFREQ_CLEANUP; - ret = zfcp_fsf_setup_ct_els(req, ct->req, ct->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, ct->sgt_req.sgl, ct->sgt_resp.sgl, + timeout); if (ret) goto failed_send; @@ -1342,7 +1343,8 @@ int zfcp_fsf_send_els(struct zfcp_adapter *adapter, u32 d_id, if (!zfcp_adapter_multi_buffer_active(adapter)) zfcp_qdio_sbal_limit(qdio, &req->qdio_req, 2); - ret = zfcp_fsf_setup_ct_els(req, els->req, els->resp, timeout); + ret = zfcp_fsf_setup_ct_els(req, els->sgt_req.sgl, els->sgt_resp.sgl, + timeout); if (ret) goto failed_send; diff --git a/drivers/s390/scsi/zfcp_fsf.h b/drivers/s390/scsi/zfcp_fsf.h index 4b92e85ec71d..22e7fd933a78 100644 --- a/drivers/s390/scsi/zfcp_fsf.h +++ b/drivers/s390/scsi/zfcp_fsf.h @@ -487,8 +487,9 @@ struct zfcp_blk_drv_data { /** * struct zfcp_fsf_ct_els - zfcp data for ct or els request - * @req: scatter-gather list for request, points to &zfcp_fc_req.sg_req or BSG - * @resp: scatter-gather list for response, points to &zfcp_fc_req.sg_rsp or BSG + * @sgt_req: sg_table for request, its sgl points to &zfcp_fc_req.sg_req or BSG + * @sgt_resp: sg_table for response, its sgl points to &zfcp_fc_req.sg_resp + * or BSG * @handler: handler function (called for response to the request) * @handler_data: data passed to handler function * @port: Optional pointer to port for zfcp internal ELS (only test link ADISC) @@ -496,8 +497,8 @@ struct zfcp_blk_drv_data { * @d_id: Destination ID of either open WKA port for CT or of D_ID for ELS */ struct zfcp_fsf_ct_els { - struct scatterlist *req; - struct scatterlist *resp; + struct sg_table sgt_req; + struct sg_table sgt_resp; void (*handler)(void *); void *handler_data; struct zfcp_port *port; -- 2.53.0 ^ permalink raw reply related [flat|nested] 12+ messages in thread
* Re: [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure 2026-10-21 8:33 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil @ 2026-10-21 8:40 ` sashiko-bot 0 siblings, 0 replies; 12+ messages in thread From: sashiko-bot @ 2026-10-21 8:40 UTC (permalink / raw) To: M Nikhil, linux-s390 Cc: Heiko Carstens, Vasily Gorbik, Alexander Gordeev, Christian Borntraeger > The zfcp_fsf_ct_els data structure is updated to replace the sg_req and > sg_resp members, which are of type struct scatterlist, with request and > response sg_table instances. > > These sg_table structure reference the corresponding scatterlists > (sg_req and sg_resp) maintained in struct zfcp_fc_req. > > These changes allows to track the original and mapped scatterlist nents > once zfcp is converted to use DMA-API for mapping the sg lists. > > Signed-off-by: M Nikhil <nikh1092@linux.ibm.com> Sashiko has reviewed this patch and found no issues. -- Sashiko AI review · https://sashiko.dev/#/patchset/20261021083351.1626409-1-nikh1092@linux.ibm.com?part=1 ^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2026-10-26 10:44 UTC | newest] Thread overview: 12+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2026-10-26 4:16 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil 2026-10-26 4:16 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 2026-10-26 9:08 ` sashiko-bot 2026-10-26 4:16 ` [PATCH v13 2/2] zfcp: Use DMA streaming API to map I/O M Nikhil -- strict thread matches above, loose matches on Subject: below -- 2026-10-26 10:12 [PATCH v13 0/2] " M Nikhil 2026-10-26 10:13 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 2026-10-26 10:44 ` sashiko-bot 2026-10-23 11:40 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil 2026-10-23 11:40 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 2026-10-23 11:47 ` sashiko-bot 2026-10-22 17:08 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil 2026-10-22 17:08 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 2026-10-22 17:14 ` sashiko-bot 2026-10-21 8:33 [PATCH v13 0/2] zfcp: Use DMA streaming API to map I/O M Nikhil 2026-10-21 8:33 ` [PATCH v13 1/2] zfcp: Replace sg-list with sg_table in zfcp_fsf_ct_els structure M Nikhil 2026-10-21 8:40 ` sashiko-bot
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