Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp

Conflicts:
	litmus/sched_cedf.c

1 files changed, 374 insertions, 0 deletions

diff --git a/drivers/target/tcm_fc/tfc_io.c b/drivers/target/tcm_fc/tfc_io.c
new file mode 100644
index 000000000000..8c4a24077d9d
--- /dev/null
+++ b/drivers/target/tcm_fc/tfc_io.c
@@ -0,0 +1,374 @@
+/*
+ * 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 <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/target_core_base.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 se_transport_task *task;
+        struct fc_frame *fp = NULL;
+        struct fc_exch *ep;
+        struct fc_lport *lport;
+        struct se_mem *mem;
+        size_t remaining;
+        u32 f_ctl = FC_FC_EX_CTX | FC_FC_REL_OFF;
+        u32 mem_off;
+        u32 fh_off = 0;
+        u32 frame_off = 0;
+        size_t frame_len = 0;
+        size_t mem_len;
+        size_t tlen;
+        size_t off_in_page;
+        struct page *page;
+        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);
+
+        task = T_TASK(se_cmd);
+        BUG_ON(!task);
+        remaining = se_cmd->data_length;
+
+        /*
+         * Setup to use first mem list entry if any.
+         */
+        if (task->t_tasks_se_num) {
+                mem = list_first_entry(task->t_mem_list,
+                         struct se_mem, se_list);
+                mem_len = mem->se_len;
+                mem_off = mem->se_off;
+                page = mem->se_page;
+        } else {
+                mem = NULL;
+                mem_len = remaining;
+                mem_off = 0;
+                page = NULL;
+        }
+
+        /* no scatter/gather in skb for odd word length due to fc_seq_send() */
+        use_sg = !(remaining % 4);
+
+        while (remaining) {
+                if (!mem_len) {
+                        BUG_ON(!mem);
+                        mem = list_entry(mem->se_list.next,
+                                struct se_mem, se_list);
+                        mem_len = min((size_t)mem->se_len, remaining);
+                        mem_off = mem->se_off;
+                        page = mem->se_page;
+                }
+                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) {
+                        if (!mem) {
+                                BUG_ON(!task->t_task_buf);
+                                page_addr = task->t_task_buf + mem_off;
+                                /*
+                                 * In this case, offset is 'offset_in_page' of
+                                 * (t_task_buf + mem_off) instead of 'mem_off'.
+                                 */
+                                off_in_page = offset_in_page(page_addr);
+                                page = virt_to_page(page_addr);
+                                tlen = min(tlen, PAGE_SIZE - off_in_page);
+                        } else
+                                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 if (mem) {
+                        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;
+                } else {
+                        from = task->t_task_buf + mem_off;
+                        memcpy(to, from, tlen);
+                        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 */
+                        if (printk_ratelimit())
+                                printk(KERN_ERR "%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 se_transport_task *task;
+        struct fc_frame_header *fh;
+        struct se_mem *mem;
+        u32 mem_off;
+        u32 rel_off;
+        size_t frame_len;
+        size_t mem_len;
+        size_t tlen;
+        struct page *page;
+        void *page_addr;
+        void *from;
+        void *to;
+        u32 f_ctl;
+        void *buf;
+
+        task = T_TASK(se_cmd);
+        BUG_ON(!task);
+
+        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) {
+                printk(KERN_INFO "%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
+                         */
+                        printk(KERN_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 if any.
+         */
+        if (task->t_tasks_se_num) {
+                mem = list_first_entry(task->t_mem_list,
+                                       struct se_mem, se_list);
+                mem_len = mem->se_len;
+                mem_off = mem->se_off;
+                page = mem->se_page;
+        } else {
+                mem = NULL;
+                page = NULL;
+                mem_off = 0;
+                mem_len = frame_len;
+        }
+
+        while (frame_len) {
+                if (!mem_len) {
+                        BUG_ON(!mem);
+                        mem = list_entry(mem->se_list.next,
+                                         struct se_mem, se_list);
+                        mem_len = mem->se_len;
+                        mem_off = mem->se_off;
+                        page = mem->se_page;
+                }
+                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);
+
+                if (mem) {
+                        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);
+                } else {
+                        to = task->t_task_buf + mem_off;
+                        memcpy(to, from, tlen);
+                }
+                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);
+}