diff options
Diffstat (limited to 'kernel/drivers/target/tcm_fc/tfc_cmd.c')
-rw-r--r-- | kernel/drivers/target/tcm_fc/tfc_cmd.c | 585 |
1 files changed, 585 insertions, 0 deletions
diff --git a/kernel/drivers/target/tcm_fc/tfc_cmd.c b/kernel/drivers/target/tcm_fc/tfc_cmd.c new file mode 100644 index 000000000..edcafa449 --- /dev/null +++ b/kernel/drivers/target/tcm_fc/tfc_cmd.c @@ -0,0 +1,585 @@ +/* + * Copyright (c) 2010 Cisco Systems, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + */ + +/* XXX TBD some includes may be extraneous */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/kthread.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/configfs.h> +#include <linux/ctype.h> +#include <linux/hash.h> +#include <linux/percpu_ida.h> +#include <asm/unaligned.h> +#include <scsi/scsi.h> +#include <scsi/scsi_host.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_tcq.h> +#include <scsi/libfc.h> +#include <scsi/fc_encode.h> + +#include <target/target_core_base.h> +#include <target/target_core_fabric.h> +#include <target/target_core_configfs.h> +#include <target/configfs_macros.h> + +#include "tcm_fc.h" + +/* + * Dump cmd state for debugging. + */ +static void _ft_dump_cmd(struct ft_cmd *cmd, const char *caller) +{ + struct fc_exch *ep; + struct fc_seq *sp; + struct se_cmd *se_cmd; + struct scatterlist *sg; + int count; + + se_cmd = &cmd->se_cmd; + pr_debug("%s: cmd %p sess %p seq %p se_cmd %p\n", + caller, cmd, cmd->sess, cmd->seq, se_cmd); + + pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n", + caller, cmd, se_cmd->t_data_nents, + se_cmd->data_length, se_cmd->se_cmd_flags); + + for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count) + pr_debug("%s: cmd %p sg %p page %p " + "len 0x%x off 0x%x\n", + caller, cmd, sg, + sg_page(sg), sg->length, sg->offset); + + sp = cmd->seq; + if (sp) { + ep = fc_seq_exch(sp); + pr_debug("%s: cmd %p sid %x did %x " + "ox_id %x rx_id %x seq_id %x e_stat %x\n", + caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid, + sp->id, ep->esb_stat); + } +} + +void ft_dump_cmd(struct ft_cmd *cmd, const char *caller) +{ + if (unlikely(ft_debug_logging)) + _ft_dump_cmd(cmd, caller); +} + +static void ft_free_cmd(struct ft_cmd *cmd) +{ + struct fc_frame *fp; + struct fc_lport *lport; + struct ft_sess *sess; + + if (!cmd) + return; + sess = cmd->sess; + fp = cmd->req_frame; + lport = fr_dev(fp); + if (fr_seq(fp)) + lport->tt.seq_release(fr_seq(fp)); + fc_frame_free(fp); + percpu_ida_free(&sess->se_sess->sess_tag_pool, cmd->se_cmd.map_tag); + ft_sess_put(sess); /* undo get from lookup at recv */ +} + +void ft_release_cmd(struct se_cmd *se_cmd) +{ + struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); + + ft_free_cmd(cmd); +} + +int ft_check_stop_free(struct se_cmd *se_cmd) +{ + transport_generic_free_cmd(se_cmd, 0); + return 1; +} + +/* + * Send response. + */ +int ft_queue_status(struct se_cmd *se_cmd) +{ + struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); + struct fc_frame *fp; + struct fcp_resp_with_ext *fcp; + struct fc_lport *lport; + struct fc_exch *ep; + size_t len; + int rc; + + if (cmd->aborted) + return 0; + ft_dump_cmd(cmd, __func__); + ep = fc_seq_exch(cmd->seq); + lport = ep->lp; + len = sizeof(*fcp) + se_cmd->scsi_sense_length; + fp = fc_frame_alloc(lport, len); + if (!fp) { + se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL; + return -ENOMEM; + } + + fcp = fc_frame_payload_get(fp, len); + memset(fcp, 0, len); + fcp->resp.fr_status = se_cmd->scsi_status; + + len = se_cmd->scsi_sense_length; + if (len) { + fcp->resp.fr_flags |= FCP_SNS_LEN_VAL; + fcp->ext.fr_sns_len = htonl(len); + memcpy((fcp + 1), se_cmd->sense_buffer, len); + } + + /* + * Test underflow and overflow with one mask. Usually both are off. + * Bidirectional commands are not handled yet. + */ + if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) { + if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) + fcp->resp.fr_flags |= FCP_RESID_OVER; + else + fcp->resp.fr_flags |= FCP_RESID_UNDER; + fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count); + } + + /* + * Send response. + */ + cmd->seq = lport->tt.seq_start_next(cmd->seq); + fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP, + FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0); + + rc = lport->tt.seq_send(lport, cmd->seq, fp); + if (rc) { + pr_info_ratelimited("%s: Failed to send response frame %p, " + "xid <0x%x>\n", __func__, fp, ep->xid); + /* + * Generate a TASK_SET_FULL status to notify the initiator + * to reduce it's queue_depth after the se_cmd response has + * been re-queued by target-core. + */ + se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL; + return -ENOMEM; + } + lport->tt.exch_done(cmd->seq); + return 0; +} + +int ft_write_pending_status(struct se_cmd *se_cmd) +{ + struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); + + return cmd->write_data_len != se_cmd->data_length; +} + +/* + * Send TX_RDY (transfer ready). + */ +int ft_write_pending(struct se_cmd *se_cmd) +{ + struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); + struct fc_frame *fp; + struct fcp_txrdy *txrdy; + struct fc_lport *lport; + struct fc_exch *ep; + struct fc_frame_header *fh; + u32 f_ctl; + + ft_dump_cmd(cmd, __func__); + + if (cmd->aborted) + return 0; + ep = fc_seq_exch(cmd->seq); + lport = ep->lp; + fp = fc_frame_alloc(lport, sizeof(*txrdy)); + if (!fp) + return -ENOMEM; /* Signal QUEUE_FULL */ + + txrdy = fc_frame_payload_get(fp, sizeof(*txrdy)); + memset(txrdy, 0, sizeof(*txrdy)); + txrdy->ft_burst_len = htonl(se_cmd->data_length); + + cmd->seq = lport->tt.seq_start_next(cmd->seq); + fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP, + FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); + + fh = fc_frame_header_get(fp); + f_ctl = ntoh24(fh->fh_f_ctl); + + /* Only if it is 'Exchange Responder' */ + if (f_ctl & FC_FC_EX_CTX) { + /* Target is 'exchange responder' and sending XFER_READY + * to 'exchange initiator (initiator)' + */ + if ((ep->xid <= lport->lro_xid) && + (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) { + if ((se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && + lport->tt.ddp_target(lport, ep->xid, + se_cmd->t_data_sg, + se_cmd->t_data_nents)) + cmd->was_ddp_setup = 1; + } + } + lport->tt.seq_send(lport, cmd->seq, fp); + return 0; +} + +u32 ft_get_task_tag(struct se_cmd *se_cmd) +{ + struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); + + if (cmd->aborted) + return ~0; + return fc_seq_exch(cmd->seq)->rxid; +} + +int ft_get_cmd_state(struct se_cmd *se_cmd) +{ + return 0; +} + +/* + * FC sequence response handler for follow-on sequences (data) and aborts. + */ +static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg) +{ + struct ft_cmd *cmd = arg; + struct fc_frame_header *fh; + + if (unlikely(IS_ERR(fp))) { + /* XXX need to find cmd if queued */ + cmd->seq = NULL; + cmd->aborted = true; + return; + } + + fh = fc_frame_header_get(fp); + + switch (fh->fh_r_ctl) { + case FC_RCTL_DD_SOL_DATA: /* write data */ + ft_recv_write_data(cmd, fp); + break; + case FC_RCTL_DD_UNSOL_CTL: /* command */ + case FC_RCTL_DD_SOL_CTL: /* transfer ready */ + case FC_RCTL_DD_DATA_DESC: /* transfer ready */ + default: + pr_debug("%s: unhandled frame r_ctl %x\n", + __func__, fh->fh_r_ctl); + ft_invl_hw_context(cmd); + fc_frame_free(fp); + transport_generic_free_cmd(&cmd->se_cmd, 0); + break; + } +} + +/* + * Send a FCP response including SCSI status and optional FCP rsp_code. + * status is SAM_STAT_GOOD (zero) iff code is valid. + * This is used in error cases, such as allocation failures. + */ +static void ft_send_resp_status(struct fc_lport *lport, + const struct fc_frame *rx_fp, + u32 status, enum fcp_resp_rsp_codes code) +{ + struct fc_frame *fp; + struct fc_seq *sp; + const struct fc_frame_header *fh; + size_t len; + struct fcp_resp_with_ext *fcp; + struct fcp_resp_rsp_info *info; + + fh = fc_frame_header_get(rx_fp); + pr_debug("FCP error response: did %x oxid %x status %x code %x\n", + ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code); + len = sizeof(*fcp); + if (status == SAM_STAT_GOOD) + len += sizeof(*info); + fp = fc_frame_alloc(lport, len); + if (!fp) + return; + fcp = fc_frame_payload_get(fp, len); + memset(fcp, 0, len); + fcp->resp.fr_status = status; + if (status == SAM_STAT_GOOD) { + fcp->ext.fr_rsp_len = htonl(sizeof(*info)); + fcp->resp.fr_flags |= FCP_RSP_LEN_VAL; + info = (struct fcp_resp_rsp_info *)(fcp + 1); + info->rsp_code = code; + } + + fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0); + sp = fr_seq(fp); + if (sp) { + lport->tt.seq_send(lport, sp, fp); + lport->tt.exch_done(sp); + } else { + lport->tt.frame_send(lport, fp); + } +} + +/* + * Send error or task management response. + */ +static void ft_send_resp_code(struct ft_cmd *cmd, + enum fcp_resp_rsp_codes code) +{ + ft_send_resp_status(cmd->sess->tport->lport, + cmd->req_frame, SAM_STAT_GOOD, code); +} + + +/* + * Send error or task management response. + * Always frees the cmd and associated state. + */ +static void ft_send_resp_code_and_free(struct ft_cmd *cmd, + enum fcp_resp_rsp_codes code) +{ + ft_send_resp_code(cmd, code); + ft_free_cmd(cmd); +} + +/* + * Handle Task Management Request. + */ +static void ft_send_tm(struct ft_cmd *cmd) +{ + struct fcp_cmnd *fcp; + int rc; + u8 tm_func; + + fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp)); + + switch (fcp->fc_tm_flags) { + case FCP_TMF_LUN_RESET: + tm_func = TMR_LUN_RESET; + break; + case FCP_TMF_TGT_RESET: + tm_func = TMR_TARGET_WARM_RESET; + break; + case FCP_TMF_CLR_TASK_SET: + tm_func = TMR_CLEAR_TASK_SET; + break; + case FCP_TMF_ABT_TASK_SET: + tm_func = TMR_ABORT_TASK_SET; + break; + case FCP_TMF_CLR_ACA: + tm_func = TMR_CLEAR_ACA; + break; + default: + /* + * FCP4r01 indicates having a combination of + * tm_flags set is invalid. + */ + pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags); + ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID); + return; + } + + /* FIXME: Add referenced task tag for ABORT_TASK */ + rc = target_submit_tmr(&cmd->se_cmd, cmd->sess->se_sess, + &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun), + cmd, tm_func, GFP_KERNEL, 0, 0); + if (rc < 0) + ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED); +} + +/* + * Send status from completed task management request. + */ +void ft_queue_tm_resp(struct se_cmd *se_cmd) +{ + struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); + struct se_tmr_req *tmr = se_cmd->se_tmr_req; + enum fcp_resp_rsp_codes code; + + if (cmd->aborted) + return; + switch (tmr->response) { + case TMR_FUNCTION_COMPLETE: + code = FCP_TMF_CMPL; + break; + case TMR_LUN_DOES_NOT_EXIST: + code = FCP_TMF_INVALID_LUN; + break; + case TMR_FUNCTION_REJECTED: + code = FCP_TMF_REJECTED; + break; + case TMR_TASK_DOES_NOT_EXIST: + case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED: + default: + code = FCP_TMF_FAILED; + break; + } + pr_debug("tmr fn %d resp %d fcp code %d\n", + tmr->function, tmr->response, code); + ft_send_resp_code(cmd, code); +} + +void ft_aborted_task(struct se_cmd *se_cmd) +{ + return; +} + +static void ft_send_work(struct work_struct *work); + +/* + * Handle incoming FCP command. + */ +static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp) +{ + struct ft_cmd *cmd; + struct fc_lport *lport = sess->tport->lport; + struct se_session *se_sess = sess->se_sess; + int tag; + + tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING); + if (tag < 0) + goto busy; + + cmd = &((struct ft_cmd *)se_sess->sess_cmd_map)[tag]; + memset(cmd, 0, sizeof(struct ft_cmd)); + + cmd->se_cmd.map_tag = tag; + cmd->sess = sess; + cmd->seq = lport->tt.seq_assign(lport, fp); + if (!cmd->seq) { + percpu_ida_free(&se_sess->sess_tag_pool, tag); + goto busy; + } + cmd->req_frame = fp; /* hold frame during cmd */ + + INIT_WORK(&cmd->work, ft_send_work); + queue_work(sess->tport->tpg->workqueue, &cmd->work); + return; + +busy: + pr_debug("cmd or seq allocation failure - sending BUSY\n"); + ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0); + fc_frame_free(fp); + ft_sess_put(sess); /* undo get from lookup */ +} + + +/* + * Handle incoming FCP frame. + * Caller has verified that the frame is type FCP. + */ +void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp) +{ + struct fc_frame_header *fh = fc_frame_header_get(fp); + + switch (fh->fh_r_ctl) { + case FC_RCTL_DD_UNSOL_CMD: /* command */ + ft_recv_cmd(sess, fp); + break; + case FC_RCTL_DD_SOL_DATA: /* write data */ + case FC_RCTL_DD_UNSOL_CTL: + case FC_RCTL_DD_SOL_CTL: + case FC_RCTL_DD_DATA_DESC: /* transfer ready */ + case FC_RCTL_ELS4_REQ: /* SRR, perhaps */ + default: + pr_debug("%s: unhandled frame r_ctl %x\n", + __func__, fh->fh_r_ctl); + fc_frame_free(fp); + ft_sess_put(sess); /* undo get from lookup */ + break; + } +} + +/* + * Send new command to target. + */ +static void ft_send_work(struct work_struct *work) +{ + struct ft_cmd *cmd = container_of(work, struct ft_cmd, work); + struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame); + struct fcp_cmnd *fcp; + int data_dir = 0; + int task_attr; + + fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp)); + if (!fcp) + goto err; + + if (fcp->fc_flags & FCP_CFL_LEN_MASK) + goto err; /* not handling longer CDBs yet */ + + /* + * Check for FCP task management flags + */ + if (fcp->fc_tm_flags) { + ft_send_tm(cmd); + return; + } + + switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) { + case 0: + data_dir = DMA_NONE; + break; + case FCP_CFL_RDDATA: + data_dir = DMA_FROM_DEVICE; + break; + case FCP_CFL_WRDATA: + data_dir = DMA_TO_DEVICE; + break; + case FCP_CFL_WRDATA | FCP_CFL_RDDATA: + goto err; /* TBD not supported by tcm_fc yet */ + } + /* + * Locate the SAM Task Attr from fc_pri_ta + */ + switch (fcp->fc_pri_ta & FCP_PTA_MASK) { + case FCP_PTA_HEADQ: + task_attr = TCM_HEAD_TAG; + break; + case FCP_PTA_ORDERED: + task_attr = TCM_ORDERED_TAG; + break; + case FCP_PTA_ACA: + task_attr = TCM_ACA_TAG; + break; + case FCP_PTA_SIMPLE: /* Fallthrough */ + default: + task_attr = TCM_SIMPLE_TAG; + } + + fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd); + /* + * Use a single se_cmd->cmd_kref as we expect to release se_cmd + * directly from ft_check_stop_free callback in response path. + */ + if (target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, fcp->fc_cdb, + &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun), + ntohl(fcp->fc_dl), task_attr, data_dir, 0)) + goto err; + + pr_debug("r_ctl %x alloc target_submit_cmd\n", fh->fh_r_ctl); + return; + +err: + ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID); +} |