| /* |
| * Copyright (c) 2010 Cisco Systems, Inc. |
| * |
| * Portions based on tcm_loop_fabric_scsi.c and libfc/fc_fcp.c |
| * |
| * Copyright (c) 2007 Intel Corporation. All rights reserved. |
| * Copyright (c) 2008 Red Hat, Inc. All rights reserved. |
| * Copyright (c) 2008 Mike Christie |
| * Copyright (c) 2009 Rising Tide, Inc. |
| * Copyright (c) 2009 Linux-iSCSI.org |
| * Copyright (c) 2009 Nicholas A. Bellinger <nab@linux-iscsi.org> |
| * |
| * 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/version.h> |
| #include <generated/utsrelease.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/ratelimit.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/libfc.h> |
| #include <scsi/fc_encode.h> |
| |
| #include <target/target_core_base.h> |
| #include <target/target_core_transport.h> |
| #include <target/target_core_fabric_ops.h> |
| #include <target/target_core_device.h> |
| #include <target/target_core_tpg.h> |
| #include <target/target_core_configfs.h> |
| #include <target/configfs_macros.h> |
| |
| #include "tcm_fc.h" |
| |
| /* |
| * Deliver read data back to initiator. |
| * XXX TBD handle resource problems later. |
| */ |
| int ft_queue_data_in(struct se_cmd *se_cmd) |
| { |
| struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd); |
| struct fc_frame *fp = NULL; |
| struct fc_exch *ep; |
| struct fc_lport *lport; |
| struct scatterlist *sg = NULL; |
| size_t remaining; |
| u32 f_ctl = FC_FC_EX_CTX | FC_FC_REL_OFF; |
| u32 mem_off = 0; |
| u32 fh_off = 0; |
| u32 frame_off = 0; |
| size_t frame_len = 0; |
| size_t mem_len = 0; |
| size_t tlen; |
| size_t off_in_page; |
| struct page *page = NULL; |
| int use_sg; |
| int error; |
| void *page_addr; |
| void *from; |
| void *to = NULL; |
| |
| ep = fc_seq_exch(cmd->seq); |
| lport = ep->lp; |
| cmd->seq = lport->tt.seq_start_next(cmd->seq); |
| |
| remaining = se_cmd->data_length; |
| |
| /* |
| * Setup to use first mem list entry, unless no data. |
| */ |
| BUG_ON(remaining && !se_cmd->t_data_sg); |
| if (remaining) { |
| sg = se_cmd->t_data_sg; |
| mem_len = sg->length; |
| mem_off = sg->offset; |
| page = sg_page(sg); |
| } |
| |
| /* no scatter/gather in skb for odd word length due to fc_seq_send() */ |
| use_sg = !(remaining % 4); |
| |
| while (remaining) { |
| if (!mem_len) { |
| sg = sg_next(sg); |
| mem_len = min((size_t)sg->length, remaining); |
| mem_off = sg->offset; |
| page = sg_page(sg); |
| } |
| if (!frame_len) { |
| /* |
| * If lport's has capability of Large Send Offload LSO) |
| * , then allow 'frame_len' to be as big as 'lso_max' |
| * if indicated transfer length is >= lport->lso_max |
| */ |
| frame_len = (lport->seq_offload) ? lport->lso_max : |
| cmd->sess->max_frame; |
| frame_len = min(frame_len, remaining); |
| fp = fc_frame_alloc(lport, use_sg ? 0 : frame_len); |
| if (!fp) |
| return -ENOMEM; |
| to = fc_frame_payload_get(fp, 0); |
| fh_off = frame_off; |
| frame_off += frame_len; |
| /* |
| * Setup the frame's max payload which is used by base |
| * driver to indicate HW about max frame size, so that |
| * HW can do fragmentation appropriately based on |
| * "gso_max_size" of underline netdev. |
| */ |
| fr_max_payload(fp) = cmd->sess->max_frame; |
| } |
| tlen = min(mem_len, frame_len); |
| |
| if (use_sg) { |
| off_in_page = mem_off; |
| BUG_ON(!page); |
| get_page(page); |
| skb_fill_page_desc(fp_skb(fp), |
| skb_shinfo(fp_skb(fp))->nr_frags, |
| page, off_in_page, tlen); |
| fr_len(fp) += tlen; |
| fp_skb(fp)->data_len += tlen; |
| fp_skb(fp)->truesize += |
| PAGE_SIZE << compound_order(page); |
| } else { |
| BUG_ON(!page); |
| from = kmap_atomic(page + (mem_off >> PAGE_SHIFT), |
| KM_SOFTIRQ0); |
| page_addr = from; |
| from += mem_off & ~PAGE_MASK; |
| tlen = min(tlen, (size_t)(PAGE_SIZE - |
| (mem_off & ~PAGE_MASK))); |
| memcpy(to, from, tlen); |
| kunmap_atomic(page_addr, KM_SOFTIRQ0); |
| to += tlen; |
| } |
| |
| mem_off += tlen; |
| mem_len -= tlen; |
| frame_len -= tlen; |
| remaining -= tlen; |
| |
| if (frame_len && |
| (skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN)) |
| continue; |
| if (!remaining) |
| f_ctl |= FC_FC_END_SEQ; |
| fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid, |
| FC_TYPE_FCP, f_ctl, fh_off); |
| error = lport->tt.seq_send(lport, cmd->seq, fp); |
| if (error) { |
| /* XXX For now, initiator will retry */ |
| pr_err_ratelimited("%s: Failed to send frame %p, " |
| "xid <0x%x>, remaining %zu, " |
| "lso_max <0x%x>\n", |
| __func__, fp, ep->xid, |
| remaining, lport->lso_max); |
| } |
| } |
| return ft_queue_status(se_cmd); |
| } |
| |
| /* |
| * Receive write data frame. |
| */ |
| void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp) |
| { |
| struct se_cmd *se_cmd = &cmd->se_cmd; |
| struct fc_seq *seq = cmd->seq; |
| struct fc_exch *ep; |
| struct fc_lport *lport; |
| struct fc_frame_header *fh; |
| struct scatterlist *sg = NULL; |
| u32 mem_off = 0; |
| u32 rel_off; |
| size_t frame_len; |
| size_t mem_len = 0; |
| size_t tlen; |
| struct page *page = NULL; |
| void *page_addr; |
| void *from; |
| void *to; |
| u32 f_ctl; |
| void *buf; |
| |
| fh = fc_frame_header_get(fp); |
| if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF)) |
| goto drop; |
| |
| /* |
| * Doesn't expect even single byte of payload. Payload |
| * is expected to be copied directly to user buffers |
| * due to DDP (Large Rx offload) feature, hence |
| * BUG_ON if BUF is non-NULL |
| */ |
| buf = fc_frame_payload_get(fp, 1); |
| if (cmd->was_ddp_setup && buf) { |
| pr_debug("%s: When DDP was setup, not expected to" |
| "receive frame with payload, Payload shall be" |
| "copied directly to buffer instead of coming " |
| "via. legacy receive queues\n", __func__); |
| BUG_ON(buf); |
| } |
| |
| /* |
| * If ft_cmd indicated 'ddp_setup', in that case only the last frame |
| * should come with 'TSI bit being set'. If 'TSI bit is not set and if |
| * data frame appears here, means error condition. In both the cases |
| * release the DDP context (ddp_put) and in error case, as well |
| * initiate error recovery mechanism. |
| */ |
| ep = fc_seq_exch(seq); |
| if (cmd->was_ddp_setup) { |
| BUG_ON(!ep); |
| lport = ep->lp; |
| BUG_ON(!lport); |
| } |
| if (cmd->was_ddp_setup && ep->xid != FC_XID_UNKNOWN) { |
| f_ctl = ntoh24(fh->fh_f_ctl); |
| /* |
| * If TSI bit set in f_ctl, means last write data frame is |
| * received successfully where payload is posted directly |
| * to user buffer and only the last frame's header is posted |
| * in legacy receive queue |
| */ |
| if (f_ctl & FC_FC_SEQ_INIT) { /* TSI bit set in FC frame */ |
| cmd->write_data_len = lport->tt.ddp_done(lport, |
| ep->xid); |
| goto last_frame; |
| } else { |
| /* |
| * Updating the write_data_len may be meaningless at |
| * this point, but just in case if required in future |
| * for debugging or any other purpose |
| */ |
| pr_err("%s: Received frame with TSI bit not" |
| " being SET, dropping the frame, " |
| "cmd->sg <%p>, cmd->sg_cnt <0x%x>\n", |
| __func__, cmd->sg, cmd->sg_cnt); |
| cmd->write_data_len = lport->tt.ddp_done(lport, |
| ep->xid); |
| lport->tt.seq_exch_abort(cmd->seq, 0); |
| goto drop; |
| } |
| } |
| |
| rel_off = ntohl(fh->fh_parm_offset); |
| frame_len = fr_len(fp); |
| if (frame_len <= sizeof(*fh)) |
| goto drop; |
| frame_len -= sizeof(*fh); |
| from = fc_frame_payload_get(fp, 0); |
| if (rel_off >= se_cmd->data_length) |
| goto drop; |
| if (frame_len + rel_off > se_cmd->data_length) |
| frame_len = se_cmd->data_length - rel_off; |
| |
| /* |
| * Setup to use first mem list entry, unless no data. |
| */ |
| BUG_ON(frame_len && !se_cmd->t_data_sg); |
| if (frame_len) { |
| sg = se_cmd->t_data_sg; |
| mem_len = sg->length; |
| mem_off = sg->offset; |
| page = sg_page(sg); |
| } |
| |
| while (frame_len) { |
| if (!mem_len) { |
| sg = sg_next(sg); |
| mem_len = sg->length; |
| mem_off = sg->offset; |
| page = sg_page(sg); |
| } |
| if (rel_off >= mem_len) { |
| rel_off -= mem_len; |
| mem_len = 0; |
| continue; |
| } |
| mem_off += rel_off; |
| mem_len -= rel_off; |
| rel_off = 0; |
| |
| tlen = min(mem_len, frame_len); |
| |
| to = kmap_atomic(page + (mem_off >> PAGE_SHIFT), |
| KM_SOFTIRQ0); |
| page_addr = to; |
| to += mem_off & ~PAGE_MASK; |
| tlen = min(tlen, (size_t)(PAGE_SIZE - |
| (mem_off & ~PAGE_MASK))); |
| memcpy(to, from, tlen); |
| kunmap_atomic(page_addr, KM_SOFTIRQ0); |
| |
| from += tlen; |
| frame_len -= tlen; |
| mem_off += tlen; |
| mem_len -= tlen; |
| cmd->write_data_len += tlen; |
| } |
| last_frame: |
| if (cmd->write_data_len == se_cmd->data_length) |
| transport_generic_handle_data(se_cmd); |
| drop: |
| fc_frame_free(fp); |
| } |