4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sagi Grimberg sagi@grimberg.me
commit 0b089c1ef7047652b13b4cdfdb1e0e7dbdb8c9ab upstream.
Currently we allocate rx buffers in a single contiguous buffers for headers (iser and iscsi) and data trailer. This means that most likely the data starting offset is aligned to 76 bytes (size of both headers).
This worked fine for years, but at some point this broke, resulting in data corruptions in isert when a command comes with immediate data and the underlying backend device assumes 512 bytes buffer alignment.
We assume a hard-requirement for all direct I/O buffers to be 512 bytes aligned. To fix this, we should avoid passing unaligned buffers for I/O.
Instead, we allocate our recv buffers with some extra space such that we can have the data portion align to 512 byte boundary. This also means that we cannot reference headers or data using structure but rather accessors (as they may move based on alignment). Also, get rid of the wrong __packed annotation from iser_rx_desc as this has only harmful effects (not aligned to anything).
This affects the rx descriptors for iscsi login and data plane.
Fixes: 3d75ca0adef4 ("block: introduce multi-page bvec helpers") Link: https://lore.kernel.org/r/20200904195039.31687-1-sagi@grimberg.me Reported-by: Stephen Rust srust@blockbridge.com Tested-by: Doug Dumitru doug@dumitru.com Signed-off-by: Sagi Grimberg sagi@grimberg.me Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/infiniband/ulp/isert/ib_isert.c | 93 ++++++++++++++++---------------- drivers/infiniband/ulp/isert/ib_isert.h | 41 ++++++++++---- 2 files changed, 78 insertions(+), 56 deletions(-)
--- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -190,15 +190,15 @@ isert_alloc_rx_descriptors(struct isert_ rx_desc = isert_conn->rx_descs;
for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++) { - dma_addr = ib_dma_map_single(ib_dev, (void *)rx_desc, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + dma_addr = ib_dma_map_single(ib_dev, rx_desc->buf, + ISER_RX_SIZE, DMA_FROM_DEVICE); if (ib_dma_mapping_error(ib_dev, dma_addr)) goto dma_map_fail;
rx_desc->dma_addr = dma_addr;
rx_sg = &rx_desc->rx_sg; - rx_sg->addr = rx_desc->dma_addr; + rx_sg->addr = rx_desc->dma_addr + isert_get_hdr_offset(rx_desc); rx_sg->length = ISER_RX_PAYLOAD_SIZE; rx_sg->lkey = device->pd->local_dma_lkey; rx_desc->rx_cqe.done = isert_recv_done; @@ -210,7 +210,7 @@ dma_map_fail: rx_desc = isert_conn->rx_descs; for (j = 0; j < i; j++, rx_desc++) { ib_dma_unmap_single(ib_dev, rx_desc->dma_addr, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + ISER_RX_SIZE, DMA_FROM_DEVICE); } kfree(isert_conn->rx_descs); isert_conn->rx_descs = NULL; @@ -231,7 +231,7 @@ isert_free_rx_descriptors(struct isert_c rx_desc = isert_conn->rx_descs; for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++) { ib_dma_unmap_single(ib_dev, rx_desc->dma_addr, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + ISER_RX_SIZE, DMA_FROM_DEVICE); }
kfree(isert_conn->rx_descs); @@ -416,10 +416,9 @@ isert_free_login_buf(struct isert_conn * ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE); kfree(isert_conn->login_rsp_buf);
- ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma, - ISER_RX_PAYLOAD_SIZE, - DMA_FROM_DEVICE); - kfree(isert_conn->login_req_buf); + ib_dma_unmap_single(ib_dev, isert_conn->login_desc->dma_addr, + ISER_RX_SIZE, DMA_FROM_DEVICE); + kfree(isert_conn->login_desc); }
static int @@ -428,25 +427,25 @@ isert_alloc_login_buf(struct isert_conn { int ret;
- isert_conn->login_req_buf = kzalloc(sizeof(*isert_conn->login_req_buf), + isert_conn->login_desc = kzalloc(sizeof(*isert_conn->login_desc), GFP_KERNEL); - if (!isert_conn->login_req_buf) + if (!isert_conn->login_desc) return -ENOMEM;
- isert_conn->login_req_dma = ib_dma_map_single(ib_dev, - isert_conn->login_req_buf, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); - ret = ib_dma_mapping_error(ib_dev, isert_conn->login_req_dma); + isert_conn->login_desc->dma_addr = ib_dma_map_single(ib_dev, + isert_conn->login_desc->buf, + ISER_RX_SIZE, DMA_FROM_DEVICE); + ret = ib_dma_mapping_error(ib_dev, isert_conn->login_desc->dma_addr); if (ret) { - isert_err("login_req_dma mapping error: %d\n", ret); - isert_conn->login_req_dma = 0; - goto out_free_login_req_buf; + isert_err("login_desc dma mapping error: %d\n", ret); + isert_conn->login_desc->dma_addr = 0; + goto out_free_login_desc; }
isert_conn->login_rsp_buf = kzalloc(ISER_RX_PAYLOAD_SIZE, GFP_KERNEL); if (!isert_conn->login_rsp_buf) { ret = -ENOMEM; - goto out_unmap_login_req_buf; + goto out_unmap_login_desc; }
isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev, @@ -463,11 +462,11 @@ isert_alloc_login_buf(struct isert_conn
out_free_login_rsp_buf: kfree(isert_conn->login_rsp_buf); -out_unmap_login_req_buf: - ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); -out_free_login_req_buf: - kfree(isert_conn->login_req_buf); +out_unmap_login_desc: + ib_dma_unmap_single(ib_dev, isert_conn->login_desc->dma_addr, + ISER_RX_SIZE, DMA_FROM_DEVICE); +out_free_login_desc: + kfree(isert_conn->login_desc); return ret; }
@@ -586,7 +585,7 @@ isert_connect_release(struct isert_conn ib_destroy_qp(isert_conn->qp); }
- if (isert_conn->login_req_buf) + if (isert_conn->login_desc) isert_free_login_buf(isert_conn);
isert_device_put(device); @@ -976,17 +975,18 @@ isert_login_post_recv(struct isert_conn int ret;
memset(&sge, 0, sizeof(struct ib_sge)); - sge.addr = isert_conn->login_req_dma; + sge.addr = isert_conn->login_desc->dma_addr + + isert_get_hdr_offset(isert_conn->login_desc); sge.length = ISER_RX_PAYLOAD_SIZE; sge.lkey = isert_conn->device->pd->local_dma_lkey;
isert_dbg("Setup sge: addr: %llx length: %d 0x%08x\n", sge.addr, sge.length, sge.lkey);
- isert_conn->login_req_buf->rx_cqe.done = isert_login_recv_done; + isert_conn->login_desc->rx_cqe.done = isert_login_recv_done;
memset(&rx_wr, 0, sizeof(struct ib_recv_wr)); - rx_wr.wr_cqe = &isert_conn->login_req_buf->rx_cqe; + rx_wr.wr_cqe = &isert_conn->login_desc->rx_cqe; rx_wr.sg_list = &sge; rx_wr.num_sge = 1;
@@ -1063,7 +1063,7 @@ post_send: static void isert_rx_login_req(struct isert_conn *isert_conn) { - struct iser_rx_desc *rx_desc = isert_conn->login_req_buf; + struct iser_rx_desc *rx_desc = isert_conn->login_desc; int rx_buflen = isert_conn->login_req_len; struct iscsi_conn *conn = isert_conn->conn; struct iscsi_login *login = conn->conn_login; @@ -1075,7 +1075,7 @@ isert_rx_login_req(struct isert_conn *is
if (login->first_request) { struct iscsi_login_req *login_req = - (struct iscsi_login_req *)&rx_desc->iscsi_header; + (struct iscsi_login_req *)isert_get_iscsi_hdr(rx_desc); /* * Setup the initial iscsi_login values from the leading * login request PDU. @@ -1094,13 +1094,13 @@ isert_rx_login_req(struct isert_conn *is login->tsih = be16_to_cpu(login_req->tsih); }
- memcpy(&login->req[0], (void *)&rx_desc->iscsi_header, ISCSI_HDR_LEN); + memcpy(&login->req[0], isert_get_iscsi_hdr(rx_desc), ISCSI_HDR_LEN);
size = min(rx_buflen, MAX_KEY_VALUE_PAIRS); isert_dbg("Using login payload size: %d, rx_buflen: %d " "MAX_KEY_VALUE_PAIRS: %d\n", size, rx_buflen, MAX_KEY_VALUE_PAIRS); - memcpy(login->req_buf, &rx_desc->data[0], size); + memcpy(login->req_buf, isert_get_data(rx_desc), size);
if (login->first_request) { complete(&isert_conn->login_comp); @@ -1165,14 +1165,15 @@ isert_handle_scsi_cmd(struct isert_conn if (imm_data_len != data_len) { sg_nents = max(1UL, DIV_ROUND_UP(imm_data_len, PAGE_SIZE)); sg_copy_from_buffer(cmd->se_cmd.t_data_sg, sg_nents, - &rx_desc->data[0], imm_data_len); + isert_get_data(rx_desc), imm_data_len); isert_dbg("Copy Immediate sg_nents: %u imm_data_len: %d\n", sg_nents, imm_data_len); } else { sg_init_table(&isert_cmd->sg, 1); cmd->se_cmd.t_data_sg = &isert_cmd->sg; cmd->se_cmd.t_data_nents = 1; - sg_set_buf(&isert_cmd->sg, &rx_desc->data[0], imm_data_len); + sg_set_buf(&isert_cmd->sg, isert_get_data(rx_desc), + imm_data_len); isert_dbg("Transfer Immediate imm_data_len: %d\n", imm_data_len); } @@ -1241,9 +1242,9 @@ isert_handle_iscsi_dataout(struct isert_ } isert_dbg("Copying DataOut: sg_start: %p, sg_off: %u " "sg_nents: %u from %p %u\n", sg_start, sg_off, - sg_nents, &rx_desc->data[0], unsol_data_len); + sg_nents, isert_get_data(rx_desc), unsol_data_len);
- sg_copy_from_buffer(sg_start, sg_nents, &rx_desc->data[0], + sg_copy_from_buffer(sg_start, sg_nents, isert_get_data(rx_desc), unsol_data_len);
rc = iscsit_check_dataout_payload(cmd, hdr, false); @@ -1302,7 +1303,7 @@ isert_handle_text_cmd(struct isert_conn } cmd->text_in_ptr = text_in;
- memcpy(cmd->text_in_ptr, &rx_desc->data[0], payload_length); + memcpy(cmd->text_in_ptr, isert_get_data(rx_desc), payload_length);
return iscsit_process_text_cmd(conn, cmd, hdr); } @@ -1312,7 +1313,7 @@ isert_rx_opcode(struct isert_conn *isert uint32_t read_stag, uint64_t read_va, uint32_t write_stag, uint64_t write_va) { - struct iscsi_hdr *hdr = &rx_desc->iscsi_header; + struct iscsi_hdr *hdr = isert_get_iscsi_hdr(rx_desc); struct iscsi_conn *conn = isert_conn->conn; struct iscsi_cmd *cmd; struct isert_cmd *isert_cmd; @@ -1410,8 +1411,8 @@ isert_recv_done(struct ib_cq *cq, struct struct isert_conn *isert_conn = wc->qp->qp_context; struct ib_device *ib_dev = isert_conn->cm_id->device; struct iser_rx_desc *rx_desc = cqe_to_rx_desc(wc->wr_cqe); - struct iscsi_hdr *hdr = &rx_desc->iscsi_header; - struct iser_ctrl *iser_ctrl = &rx_desc->iser_header; + struct iscsi_hdr *hdr = isert_get_iscsi_hdr(rx_desc); + struct iser_ctrl *iser_ctrl = isert_get_iser_hdr(rx_desc); uint64_t read_va = 0, write_va = 0; uint32_t read_stag = 0, write_stag = 0;
@@ -1425,7 +1426,7 @@ isert_recv_done(struct ib_cq *cq, struct rx_desc->in_use = true;
ib_dma_sync_single_for_cpu(ib_dev, rx_desc->dma_addr, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + ISER_RX_SIZE, DMA_FROM_DEVICE);
isert_dbg("DMA: 0x%llx, iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n", rx_desc->dma_addr, hdr->opcode, hdr->itt, hdr->flags, @@ -1460,7 +1461,7 @@ isert_recv_done(struct ib_cq *cq, struct read_stag, read_va, write_stag, write_va);
ib_dma_sync_single_for_device(ib_dev, rx_desc->dma_addr, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + ISER_RX_SIZE, DMA_FROM_DEVICE); }
static void @@ -1474,8 +1475,8 @@ isert_login_recv_done(struct ib_cq *cq, return; }
- ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_req_dma, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_desc->dma_addr, + ISER_RX_SIZE, DMA_FROM_DEVICE);
isert_conn->login_req_len = wc->byte_len - ISER_HEADERS_LEN;
@@ -1490,8 +1491,8 @@ isert_login_recv_done(struct ib_cq *cq, complete(&isert_conn->login_req_comp); mutex_unlock(&isert_conn->mutex);
- ib_dma_sync_single_for_device(ib_dev, isert_conn->login_req_dma, - ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + ib_dma_sync_single_for_device(ib_dev, isert_conn->login_desc->dma_addr, + ISER_RX_SIZE, DMA_FROM_DEVICE); }
static void --- a/drivers/infiniband/ulp/isert/ib_isert.h +++ b/drivers/infiniband/ulp/isert/ib_isert.h @@ -59,9 +59,11 @@ ISERT_MAX_TX_MISC_PDUS + \ ISERT_MAX_RX_MISC_PDUS)
-#define ISER_RX_PAD_SIZE (ISCSI_DEF_MAX_RECV_SEG_LEN + 4096 - \ - (ISER_RX_PAYLOAD_SIZE + sizeof(u64) + sizeof(struct ib_sge) + \ - sizeof(struct ib_cqe) + sizeof(bool))) +/* + * RX size is default of 8k plus headers, but data needs to align to + * 512 boundary, so use 1024 to have the extra space for alignment. + */ +#define ISER_RX_SIZE (ISCSI_DEF_MAX_RECV_SEG_LEN + 1024)
#define ISCSI_ISER_SG_TABLESIZE 256
@@ -80,21 +82,41 @@ enum iser_conn_state { };
struct iser_rx_desc { - struct iser_ctrl iser_header; - struct iscsi_hdr iscsi_header; - char data[ISCSI_DEF_MAX_RECV_SEG_LEN]; + char buf[ISER_RX_SIZE]; u64 dma_addr; struct ib_sge rx_sg; struct ib_cqe rx_cqe; bool in_use; - char pad[ISER_RX_PAD_SIZE]; -} __packed; +};
static inline struct iser_rx_desc *cqe_to_rx_desc(struct ib_cqe *cqe) { return container_of(cqe, struct iser_rx_desc, rx_cqe); }
+static void *isert_get_iser_hdr(struct iser_rx_desc *desc) +{ + return PTR_ALIGN(desc->buf + ISER_HEADERS_LEN, 512) - ISER_HEADERS_LEN; +} + +static size_t isert_get_hdr_offset(struct iser_rx_desc *desc) +{ + return isert_get_iser_hdr(desc) - (void *)desc->buf; +} + +static void *isert_get_iscsi_hdr(struct iser_rx_desc *desc) +{ + return isert_get_iser_hdr(desc) + sizeof(struct iser_ctrl); +} + +static void *isert_get_data(struct iser_rx_desc *desc) +{ + void *data = isert_get_iser_hdr(desc) + ISER_HEADERS_LEN; + + WARN_ON((uintptr_t)data & 511); + return data; +} + struct iser_tx_desc { struct iser_ctrl iser_header; struct iscsi_hdr iscsi_header; @@ -141,9 +163,8 @@ struct isert_conn { u32 responder_resources; u32 initiator_depth; bool pi_support; - struct iser_rx_desc *login_req_buf; + struct iser_rx_desc *login_desc; char *login_rsp_buf; - u64 login_req_dma; int login_req_len; u64 login_rsp_dma; struct iser_rx_desc *rx_descs;