[SCSI] iscsi_tcp: hook iscsi_tcp into new libiscsi_tcp module
Mike Christie [Tue, 2 Dec 2008 06:32:12 +0000 (00:32 -0600)]
This hooks iscsi_tcp into the libiscsi_tcp module and removes
code that is now in libiscsi_tcp.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/Makefile
drivers/scsi/iscsi_tcp.c
drivers/scsi/iscsi_tcp.h

index 72fd504..b89aedf 100644 (file)
@@ -36,7 +36,7 @@ obj-$(CONFIG_SCSI_SAS_LIBSAS) += libsas/
 obj-$(CONFIG_SCSI_SRP_ATTRS)   += scsi_transport_srp.o
 obj-$(CONFIG_SCSI_DH)          += device_handler/
 
-obj-$(CONFIG_ISCSI_TCP)        += libiscsi.o   iscsi_tcp.o
+obj-$(CONFIG_ISCSI_TCP)        += libiscsi.o   libiscsi_tcp.o iscsi_tcp.o
 obj-$(CONFIG_INFINIBAND_ISER)  += libiscsi.o
 obj-$(CONFIG_SCSI_A4000T)      += 53c700.o     a4000t.o
 obj-$(CONFIG_SCSI_ZORRO7XX)    += 53c700.o     zorro7xx.o
index 97f3f68..07d9eb1 100644 (file)
@@ -27,7 +27,6 @@
  */
 
 #include <linux/types.h>
-#include <linux/list.h>
 #include <linux/inet.h>
 #include <linux/file.h>
 #include <linux/blkdev.h>
 
 #include "iscsi_tcp.h"
 
-MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
+MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
+             "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
              "Alex Aizman <itn780@yahoo.com>");
 MODULE_DESCRIPTION("iSCSI/TCP data-path");
 MODULE_LICENSE("GPL");
 #undef DEBUG_TCP
-#define DEBUG_ASSERT
 
 #ifdef DEBUG_TCP
 #define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
@@ -57,924 +56,22 @@ MODULE_LICENSE("GPL");
 #define debug_tcp(fmt...)
 #endif
 
-static struct scsi_transport_template *iscsi_tcp_scsi_transport;
-static struct scsi_host_template iscsi_sht;
-static struct iscsi_transport iscsi_tcp_transport;
+static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport;
+static struct scsi_host_template iscsi_sw_tcp_sht;
+static struct iscsi_transport iscsi_sw_tcp_transport;
 
 static unsigned int iscsi_max_lun = 512;
 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
 
-static int iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
-                                  struct iscsi_segment *segment);
-
-/*
- * Scatterlist handling: inside the iscsi_segment, we
- * remember an index into the scatterlist, and set data/size
- * to the current scatterlist entry. For highmem pages, we
- * kmap as needed.
- *
- * Note that the page is unmapped when we return from
- * TCP's data_ready handler, so we may end up mapping and
- * unmapping the same page repeatedly. The whole reason
- * for this is that we shouldn't keep the page mapped
- * outside the softirq.
- */
-
-/**
- * iscsi_tcp_segment_init_sg - init indicated scatterlist entry
- * @segment: the buffer object
- * @sg: scatterlist
- * @offset: byte offset into that sg entry
- *
- * This function sets up the segment so that subsequent
- * data is copied to the indicated sg entry, at the given
- * offset.
- */
-static inline void
-iscsi_tcp_segment_init_sg(struct iscsi_segment *segment,
-                         struct scatterlist *sg, unsigned int offset)
-{
-       segment->sg = sg;
-       segment->sg_offset = offset;
-       segment->size = min(sg->length - offset,
-                           segment->total_size - segment->total_copied);
-       segment->data = NULL;
-}
-
-/**
- * iscsi_tcp_segment_map - map the current S/G page
- * @segment: iscsi_segment
- * @recv: 1 if called from recv path
- *
- * We only need to possibly kmap data if scatter lists are being used,
- * because the iscsi passthrough and internal IO paths will never use high
- * mem pages.
- */
-static inline void
-iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv)
-{
-       struct scatterlist *sg;
-
-       if (segment->data != NULL || !segment->sg)
-               return;
-
-       sg = segment->sg;
-       BUG_ON(segment->sg_mapped);
-       BUG_ON(sg->length == 0);
-
-       /*
-        * If the page count is greater than one it is ok to send
-        * to the network layer's zero copy send path. If not we
-        * have to go the slow sendmsg path. We always map for the
-        * recv path.
-        */
-       if (page_count(sg_page(sg)) >= 1 && !recv)
-               return;
-
-       debug_tcp("iscsi_tcp_segment_map %s %p\n", recv ? "recv" : "xmit",
-                 segment);
-       segment->sg_mapped = kmap_atomic(sg_page(sg), KM_SOFTIRQ0);
-       segment->data = segment->sg_mapped + sg->offset + segment->sg_offset;
-}
-
-static inline void
-iscsi_tcp_segment_unmap(struct iscsi_segment *segment)
-{
-       debug_tcp("iscsi_tcp_segment_unmap %p\n", segment);
-
-       if (segment->sg_mapped) {
-               debug_tcp("iscsi_tcp_segment_unmap valid\n");
-               kunmap_atomic(segment->sg_mapped, KM_SOFTIRQ0);
-               segment->sg_mapped = NULL;
-               segment->data = NULL;
-       }
-}
-
-/*
- * Splice the digest buffer into the buffer
- */
-static inline void
-iscsi_tcp_segment_splice_digest(struct iscsi_segment *segment, void *digest)
-{
-       segment->data = digest;
-       segment->digest_len = ISCSI_DIGEST_SIZE;
-       segment->total_size += ISCSI_DIGEST_SIZE;
-       segment->size = ISCSI_DIGEST_SIZE;
-       segment->copied = 0;
-       segment->sg = NULL;
-       segment->hash = NULL;
-}
-
-/**
- * iscsi_tcp_segment_done - check whether the segment is complete
- * @segment: iscsi segment to check
- * @recv: set to one of this is called from the recv path
- * @copied: number of bytes copied
- *
- * Check if we're done receiving this segment. If the receive
- * buffer is full but we expect more data, move on to the
- * next entry in the scatterlist.
- *
- * If the amount of data we received isn't a multiple of 4,
- * we will transparently receive the pad bytes, too.
- *
- * This function must be re-entrant.
- */
-static inline int
-iscsi_tcp_segment_done(struct iscsi_segment *segment, int recv, unsigned copied)
-{
-       static unsigned char padbuf[ISCSI_PAD_LEN];
-       struct scatterlist sg;
-       unsigned int pad;
-
-       debug_tcp("copied %u %u size %u %s\n", segment->copied, copied,
-                 segment->size, recv ? "recv" : "xmit");
-       if (segment->hash && copied) {
-               /*
-                * If a segment is kmapd we must unmap it before sending
-                * to the crypto layer since that will try to kmap it again.
-                */
-               iscsi_tcp_segment_unmap(segment);
-
-               if (!segment->data) {
-                       sg_init_table(&sg, 1);
-                       sg_set_page(&sg, sg_page(segment->sg), copied,
-                                   segment->copied + segment->sg_offset +
-                                                       segment->sg->offset);
-               } else
-                       sg_init_one(&sg, segment->data + segment->copied,
-                                   copied);
-               crypto_hash_update(segment->hash, &sg, copied);
-       }
-
-       segment->copied += copied;
-       if (segment->copied < segment->size) {
-               iscsi_tcp_segment_map(segment, recv);
-               return 0;
-       }
-
-       segment->total_copied += segment->copied;
-       segment->copied = 0;
-       segment->size = 0;
-
-       /* Unmap the current scatterlist page, if there is one. */
-       iscsi_tcp_segment_unmap(segment);
-
-       /* Do we have more scatterlist entries? */
-       debug_tcp("total copied %u total size %u\n", segment->total_copied,
-                  segment->total_size);
-       if (segment->total_copied < segment->total_size) {
-               /* Proceed to the next entry in the scatterlist. */
-               iscsi_tcp_segment_init_sg(segment, sg_next(segment->sg),
-                                         0);
-               iscsi_tcp_segment_map(segment, recv);
-               BUG_ON(segment->size == 0);
-               return 0;
-       }
-
-       /* Do we need to handle padding? */
-       pad = iscsi_padding(segment->total_copied);
-       if (pad != 0) {
-               debug_tcp("consume %d pad bytes\n", pad);
-               segment->total_size += pad;
-               segment->size = pad;
-               segment->data = padbuf;
-               return 0;
-       }
-
-       /*
-        * Set us up for transferring the data digest. hdr digest
-        * is completely handled in hdr done function.
-        */
-       if (segment->hash) {
-               crypto_hash_final(segment->hash, segment->digest);
-               iscsi_tcp_segment_splice_digest(segment,
-                                recv ? segment->recv_digest : segment->digest);
-               return 0;
-       }
-
-       return 1;
-}
-
 /**
- * iscsi_tcp_xmit_segment - transmit segment
- * @tcp_conn: the iSCSI TCP connection
- * @segment: the buffer to transmnit
- *
- * This function transmits as much of the buffer as
- * the network layer will accept, and returns the number of
- * bytes transmitted.
- *
- * If CRC hashing is enabled, the function will compute the
- * hash as it goes. When the entire segment has been transmitted,
- * it will retrieve the hash value and send it as well.
- */
-static int
-iscsi_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
-                      struct iscsi_segment *segment)
-{
-       struct socket *sk = tcp_conn->sock;
-       unsigned int copied = 0;
-       int r = 0;
-
-       while (!iscsi_tcp_segment_done(segment, 0, r)) {
-               struct scatterlist *sg;
-               unsigned int offset, copy;
-               int flags = 0;
-
-               r = 0;
-               offset = segment->copied;
-               copy = segment->size - offset;
-
-               if (segment->total_copied + segment->size < segment->total_size)
-                       flags |= MSG_MORE;
-
-               /* Use sendpage if we can; else fall back to sendmsg */
-               if (!segment->data) {
-                       sg = segment->sg;
-                       offset += segment->sg_offset + sg->offset;
-                       r = tcp_conn->sendpage(sk, sg_page(sg), offset, copy,
-                                              flags);
-               } else {
-                       struct msghdr msg = { .msg_flags = flags };
-                       struct kvec iov = {
-                               .iov_base = segment->data + offset,
-                               .iov_len = copy
-                       };
-
-                       r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
-               }
-
-               if (r < 0) {
-                       iscsi_tcp_segment_unmap(segment);
-                       if (copied || r == -EAGAIN)
-                               break;
-                       return r;
-               }
-               copied += r;
-       }
-       return copied;
-}
-
-/**
- * iscsi_tcp_segment_recv - copy data to segment
- * @tcp_conn: the iSCSI TCP connection
- * @segment: the buffer to copy to
- * @ptr: data pointer
- * @len: amount of data available
- *
- * This function copies up to @len bytes to the
- * given buffer, and returns the number of bytes
- * consumed, which can actually be less than @len.
- *
- * If hash digest is enabled, the function will update the
- * hash while copying.
- * Combining these two operations doesn't buy us a lot (yet),
- * but in the future we could implement combined copy+crc,
- * just way we do for network layer checksums.
- */
-static int
-iscsi_tcp_segment_recv(struct iscsi_tcp_conn *tcp_conn,
-                      struct iscsi_segment *segment, const void *ptr,
-                      unsigned int len)
-{
-       unsigned int copy = 0, copied = 0;
-
-       while (!iscsi_tcp_segment_done(segment, 1, copy)) {
-               if (copied == len) {
-                       debug_tcp("iscsi_tcp_segment_recv copied %d bytes\n",
-                                 len);
-                       break;
-               }
-
-               copy = min(len - copied, segment->size - segment->copied);
-               debug_tcp("iscsi_tcp_segment_recv copying %d\n", copy);
-               memcpy(segment->data + segment->copied, ptr + copied, copy);
-               copied += copy;
-       }
-       return copied;
-}
-
-static inline void
-iscsi_tcp_dgst_header(struct hash_desc *hash, const void *hdr, size_t hdrlen,
-                     unsigned char digest[ISCSI_DIGEST_SIZE])
-{
-       struct scatterlist sg;
-
-       sg_init_one(&sg, hdr, hdrlen);
-       crypto_hash_digest(hash, &sg, hdrlen, digest);
-}
-
-static inline int
-iscsi_tcp_dgst_verify(struct iscsi_tcp_conn *tcp_conn,
-                     struct iscsi_segment *segment)
-{
-       if (!segment->digest_len)
-               return 1;
-
-       if (memcmp(segment->recv_digest, segment->digest,
-                  segment->digest_len)) {
-               debug_scsi("digest mismatch\n");
-               return 0;
-       }
-
-       return 1;
-}
-
-/*
- * Helper function to set up segment buffer
- */
-static inline void
-__iscsi_segment_init(struct iscsi_segment *segment, size_t size,
-                    iscsi_segment_done_fn_t *done, struct hash_desc *hash)
-{
-       memset(segment, 0, sizeof(*segment));
-       segment->total_size = size;
-       segment->done = done;
-
-       if (hash) {
-               segment->hash = hash;
-               crypto_hash_init(hash);
-       }
-}
-
-static inline void
-iscsi_segment_init_linear(struct iscsi_segment *segment, void *data,
-                         size_t size, iscsi_segment_done_fn_t *done,
-                         struct hash_desc *hash)
-{
-       __iscsi_segment_init(segment, size, done, hash);
-       segment->data = data;
-       segment->size = size;
-}
-
-static inline int
-iscsi_segment_seek_sg(struct iscsi_segment *segment,
-                     struct scatterlist *sg_list, unsigned int sg_count,
-                     unsigned int offset, size_t size,
-                     iscsi_segment_done_fn_t *done, struct hash_desc *hash)
-{
-       struct scatterlist *sg;
-       unsigned int i;
-
-       debug_scsi("iscsi_segment_seek_sg offset %u size %llu\n",
-                 offset, size);
-       __iscsi_segment_init(segment, size, done, hash);
-       for_each_sg(sg_list, sg, sg_count, i) {
-               debug_scsi("sg %d, len %u offset %u\n", i, sg->length,
-                          sg->offset);
-               if (offset < sg->length) {
-                       iscsi_tcp_segment_init_sg(segment, sg, offset);
-                       return 0;
-               }
-               offset -= sg->length;
-       }
-
-       return ISCSI_ERR_DATA_OFFSET;
-}
-
-/**
- * iscsi_tcp_hdr_recv_prep - prep segment for hdr reception
- * @tcp_conn: iscsi connection to prep for
- *
- * This function always passes NULL for the hash argument, because when this
- * function is called we do not yet know the final size of the header and want
- * to delay the digest processing until we know that.
- */
-static void
-iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn)
-{
-       debug_tcp("iscsi_tcp_hdr_recv_prep(%p%s)\n", tcp_conn,
-                 tcp_conn->iscsi_conn->hdrdgst_en ? ", digest enabled" : "");
-       iscsi_segment_init_linear(&tcp_conn->in.segment,
-                               tcp_conn->in.hdr_buf, sizeof(struct iscsi_hdr),
-                               iscsi_tcp_hdr_recv_done, NULL);
-}
-
-/*
- * Handle incoming reply to any other type of command
- */
-static int
-iscsi_tcp_data_recv_done(struct iscsi_tcp_conn *tcp_conn,
-                        struct iscsi_segment *segment)
-{
-       struct iscsi_conn *conn = tcp_conn->iscsi_conn;
-       int rc = 0;
-
-       if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
-               return ISCSI_ERR_DATA_DGST;
-
-       rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr,
-                       conn->data, tcp_conn->in.datalen);
-       if (rc)
-               return rc;
-
-       iscsi_tcp_hdr_recv_prep(tcp_conn);
-       return 0;
-}
-
-static void
-iscsi_tcp_data_recv_prep(struct iscsi_tcp_conn *tcp_conn)
-{
-       struct iscsi_conn *conn = tcp_conn->iscsi_conn;
-       struct hash_desc *rx_hash = NULL;
-
-       if (conn->datadgst_en &
-           !(conn->session->tt->caps & CAP_DIGEST_OFFLOAD))
-               rx_hash = &tcp_conn->rx_hash;
-
-       iscsi_segment_init_linear(&tcp_conn->in.segment,
-                               conn->data, tcp_conn->in.datalen,
-                               iscsi_tcp_data_recv_done, rx_hash);
-}
-
-/*
- * must be called with session lock
- */
-static void iscsi_tcp_cleanup_task(struct iscsi_task *task)
-{
-       struct iscsi_tcp_task *tcp_task = task->dd_data;
-       struct iscsi_r2t_info *r2t;
-
-       /* nothing to do for mgmt or pending tasks */
-       if (!task->sc || task->state == ISCSI_TASK_PENDING)
-               return;
-
-       /* flush task's r2t queues */
-       while (__kfifo_get(tcp_task->r2tqueue, (void*)&r2t, sizeof(void*))) {
-               __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
-                           sizeof(void*));
-               debug_scsi("iscsi_tcp_cleanup_task pending r2t dropped\n");
-       }
-
-       r2t = tcp_task->r2t;
-       if (r2t != NULL) {
-               __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
-                           sizeof(void*));
-               tcp_task->r2t = NULL;
-       }
-}
-
-/**
- * iscsi_tcp_data_in - SCSI Data-In Response processing
- * @conn: iscsi connection
- * @task: scsi command task
- */
-static int iscsi_tcp_data_in(struct iscsi_conn *conn, struct iscsi_task *task)
-{
-       struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct iscsi_tcp_task *tcp_task = task->dd_data;
-       struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
-       int datasn = be32_to_cpu(rhdr->datasn);
-       unsigned total_in_length = scsi_in(task->sc)->length;
-
-       iscsi_update_cmdsn(conn->session, (struct iscsi_nopin*)rhdr);
-       if (tcp_conn->in.datalen == 0)
-               return 0;
-
-       if (tcp_task->exp_datasn != datasn) {
-               debug_tcp("%s: task->exp_datasn(%d) != rhdr->datasn(%d)\n",
-                         __func__, tcp_task->exp_datasn, datasn);
-               return ISCSI_ERR_DATASN;
-       }
-
-       tcp_task->exp_datasn++;
-
-       tcp_task->data_offset = be32_to_cpu(rhdr->offset);
-       if (tcp_task->data_offset + tcp_conn->in.datalen > total_in_length) {
-               debug_tcp("%s: data_offset(%d) + data_len(%d) > total_length_in(%d)\n",
-                         __func__, tcp_task->data_offset,
-                         tcp_conn->in.datalen, total_in_length);
-               return ISCSI_ERR_DATA_OFFSET;
-       }
-
-       conn->datain_pdus_cnt++;
-       return 0;
-}
-
-/**
- * iscsi_tcp_r2t_rsp - iSCSI R2T Response processing
- * @conn: iscsi connection
- * @task: scsi command task
- */
-static int iscsi_tcp_r2t_rsp(struct iscsi_conn *conn, struct iscsi_task *task)
-{
-       struct iscsi_session *session = conn->session;
-       struct iscsi_tcp_task *tcp_task = task->dd_data;
-       struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
-       struct iscsi_r2t_info *r2t;
-       int r2tsn = be32_to_cpu(rhdr->r2tsn);
-       int rc;
-
-       if (tcp_conn->in.datalen) {
-               iscsi_conn_printk(KERN_ERR, conn,
-                                 "invalid R2t with datalen %d\n",
-                                 tcp_conn->in.datalen);
-               return ISCSI_ERR_DATALEN;
-       }
-
-       if (tcp_task->exp_datasn != r2tsn){
-               debug_tcp("%s: task->exp_datasn(%d) != rhdr->r2tsn(%d)\n",
-                         __func__, tcp_task->exp_datasn, r2tsn);
-               return ISCSI_ERR_R2TSN;
-       }
-
-       /* fill-in new R2T associated with the task */
-       iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
-
-       if (!task->sc || session->state != ISCSI_STATE_LOGGED_IN) {
-               iscsi_conn_printk(KERN_INFO, conn,
-                                 "dropping R2T itt %d in recovery.\n",
-                                 task->itt);
-               return 0;
-       }
-
-       rc = __kfifo_get(tcp_task->r2tpool.queue, (void*)&r2t, sizeof(void*));
-       if (!rc) {
-               iscsi_conn_printk(KERN_ERR, conn, "Could not allocate R2T. "
-                                 "Target has sent more R2Ts than it "
-                                 "negotiated for or driver has has leaked.\n");
-               return ISCSI_ERR_PROTO;
-       }
-
-       r2t->exp_statsn = rhdr->statsn;
-       r2t->data_length = be32_to_cpu(rhdr->data_length);
-       if (r2t->data_length == 0) {
-               iscsi_conn_printk(KERN_ERR, conn,
-                                 "invalid R2T with zero data len\n");
-               __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
-                           sizeof(void*));
-               return ISCSI_ERR_DATALEN;
-       }
-
-       if (r2t->data_length > session->max_burst)
-               debug_scsi("invalid R2T with data len %u and max burst %u."
-                          "Attempting to execute request.\n",
-                           r2t->data_length, session->max_burst);
-
-       r2t->data_offset = be32_to_cpu(rhdr->data_offset);
-       if (r2t->data_offset + r2t->data_length > scsi_out(task->sc)->length) {
-               iscsi_conn_printk(KERN_ERR, conn,
-                                 "invalid R2T with data len %u at offset %u "
-                                 "and total length %d\n", r2t->data_length,
-                                 r2t->data_offset, scsi_out(task->sc)->length);
-               __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
-                           sizeof(void*));
-               return ISCSI_ERR_DATALEN;
-       }
-
-       r2t->ttt = rhdr->ttt; /* no flip */
-       r2t->datasn = 0;
-       r2t->sent = 0;
-
-       tcp_task->exp_datasn = r2tsn + 1;
-       __kfifo_put(tcp_task->r2tqueue, (void*)&r2t, sizeof(void*));
-       conn->r2t_pdus_cnt++;
-
-       iscsi_requeue_task(task);
-       return 0;
-}
-
-/*
- * Handle incoming reply to DataIn command
- */
-static int
-iscsi_tcp_process_data_in(struct iscsi_tcp_conn *tcp_conn,
-                         struct iscsi_segment *segment)
-{
-       struct iscsi_conn *conn = tcp_conn->iscsi_conn;
-       struct iscsi_hdr *hdr = tcp_conn->in.hdr;
-       int rc;
-
-       if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
-               return ISCSI_ERR_DATA_DGST;
-
-       /* check for non-exceptional status */
-       if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
-               rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
-               if (rc)
-                       return rc;
-       }
-
-       iscsi_tcp_hdr_recv_prep(tcp_conn);
-       return 0;
-}
-
-/**
- * iscsi_tcp_hdr_dissect - process PDU header
- * @conn: iSCSI connection
- * @hdr: PDU header
- *
- * This function analyzes the header of the PDU received,
- * and performs several sanity checks. If the PDU is accompanied
- * by data, the receive buffer is set up to copy the incoming data
- * to the correct location.
- */
-static int
-iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
-{
-       int rc = 0, opcode, ahslen;
-       struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct iscsi_task *task;
-
-       /* verify PDU length */
-       tcp_conn->in.datalen = ntoh24(hdr->dlength);
-       if (tcp_conn->in.datalen > conn->max_recv_dlength) {
-               iscsi_conn_printk(KERN_ERR, conn,
-                                 "iscsi_tcp: datalen %d > %d\n",
-                                 tcp_conn->in.datalen, conn->max_recv_dlength);
-               return ISCSI_ERR_DATALEN;
-       }
-
-       /* Additional header segments. So far, we don't
-        * process additional headers.
-        */
-       ahslen = hdr->hlength << 2;
-
-       opcode = hdr->opcode & ISCSI_OPCODE_MASK;
-       /* verify itt (itt encoding: age+cid+itt) */
-       rc = iscsi_verify_itt(conn, hdr->itt);
-       if (rc)
-               return rc;
-
-       debug_tcp("opcode 0x%x ahslen %d datalen %d\n",
-                 opcode, ahslen, tcp_conn->in.datalen);
-
-       switch(opcode) {
-       case ISCSI_OP_SCSI_DATA_IN:
-               spin_lock(&conn->session->lock);
-               task = iscsi_itt_to_ctask(conn, hdr->itt);
-               if (!task)
-                       rc = ISCSI_ERR_BAD_ITT;
-               else
-                       rc = iscsi_tcp_data_in(conn, task);
-               if (rc) {
-                       spin_unlock(&conn->session->lock);
-                       break;
-               }
-
-               if (tcp_conn->in.datalen) {
-                       struct iscsi_tcp_task *tcp_task = task->dd_data;
-                       struct hash_desc *rx_hash = NULL;
-                       struct scsi_data_buffer *sdb = scsi_in(task->sc);
-
-                       /*
-                        * Setup copy of Data-In into the Scsi_Cmnd
-                        * Scatterlist case:
-                        * We set up the iscsi_segment to point to the next
-                        * scatterlist entry to copy to. As we go along,
-                        * we move on to the next scatterlist entry and
-                        * update the digest per-entry.
-                        */
-                       if (conn->datadgst_en &&
-                           !(conn->session->tt->caps & CAP_DIGEST_OFFLOAD))
-                               rx_hash = &tcp_conn->rx_hash;
-
-                       debug_tcp("iscsi_tcp_begin_data_in(%p, offset=%d, "
-                                 "datalen=%d)\n", tcp_conn,
-                                 tcp_task->data_offset,
-                                 tcp_conn->in.datalen);
-                       rc = iscsi_segment_seek_sg(&tcp_conn->in.segment,
-                                                  sdb->table.sgl,
-                                                  sdb->table.nents,
-                                                  tcp_task->data_offset,
-                                                  tcp_conn->in.datalen,
-                                                  iscsi_tcp_process_data_in,
-                                                  rx_hash);
-                       spin_unlock(&conn->session->lock);
-                       return rc;
-               }
-               rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
-               spin_unlock(&conn->session->lock);
-               break;
-       case ISCSI_OP_SCSI_CMD_RSP:
-               if (tcp_conn->in.datalen) {
-                       iscsi_tcp_data_recv_prep(tcp_conn);
-                       return 0;
-               }
-               rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
-               break;
-       case ISCSI_OP_R2T:
-               spin_lock(&conn->session->lock);
-               task = iscsi_itt_to_ctask(conn, hdr->itt);
-               if (!task)
-                       rc = ISCSI_ERR_BAD_ITT;
-               else if (ahslen)
-                       rc = ISCSI_ERR_AHSLEN;
-               else if (task->sc->sc_data_direction == DMA_TO_DEVICE)
-                       rc = iscsi_tcp_r2t_rsp(conn, task);
-               else
-                       rc = ISCSI_ERR_PROTO;
-               spin_unlock(&conn->session->lock);
-               break;
-       case ISCSI_OP_LOGIN_RSP:
-       case ISCSI_OP_TEXT_RSP:
-       case ISCSI_OP_REJECT:
-       case ISCSI_OP_ASYNC_EVENT:
-               /*
-                * It is possible that we could get a PDU with a buffer larger
-                * than 8K, but there are no targets that currently do this.
-                * For now we fail until we find a vendor that needs it
-                */
-               if (ISCSI_DEF_MAX_RECV_SEG_LEN < tcp_conn->in.datalen) {
-                       iscsi_conn_printk(KERN_ERR, conn,
-                                         "iscsi_tcp: received buffer of "
-                                         "len %u but conn buffer is only %u "
-                                         "(opcode %0x)\n",
-                                         tcp_conn->in.datalen,
-                                         ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);
-                       rc = ISCSI_ERR_PROTO;
-                       break;
-               }
-
-               /* If there's data coming in with the response,
-                * receive it to the connection's buffer.
-                */
-               if (tcp_conn->in.datalen) {
-                       iscsi_tcp_data_recv_prep(tcp_conn);
-                       return 0;
-               }
-       /* fall through */
-       case ISCSI_OP_LOGOUT_RSP:
-       case ISCSI_OP_NOOP_IN:
-       case ISCSI_OP_SCSI_TMFUNC_RSP:
-               rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
-               break;
-       default:
-               rc = ISCSI_ERR_BAD_OPCODE;
-               break;
-       }
-
-       if (rc == 0) {
-               /* Anything that comes with data should have
-                * been handled above. */
-               if (tcp_conn->in.datalen)
-                       return ISCSI_ERR_PROTO;
-               iscsi_tcp_hdr_recv_prep(tcp_conn);
-       }
-
-       return rc;
-}
-
-/**
- * iscsi_tcp_hdr_recv_done - process PDU header
- *
- * This is the callback invoked when the PDU header has
- * been received. If the header is followed by additional
- * header segments, we go back for more data.
- */
-static int
-iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
-                       struct iscsi_segment *segment)
-{
-       struct iscsi_conn *conn = tcp_conn->iscsi_conn;
-       struct iscsi_hdr *hdr;
-
-       /* Check if there are additional header segments
-        * *prior* to computing the digest, because we
-        * may need to go back to the caller for more.
-        */
-       hdr = (struct iscsi_hdr *) tcp_conn->in.hdr_buf;
-       if (segment->copied == sizeof(struct iscsi_hdr) && hdr->hlength) {
-               /* Bump the header length - the caller will
-                * just loop around and get the AHS for us, and
-                * call again. */
-               unsigned int ahslen = hdr->hlength << 2;
-
-               /* Make sure we don't overflow */
-               if (sizeof(*hdr) + ahslen > sizeof(tcp_conn->in.hdr_buf))
-                       return ISCSI_ERR_AHSLEN;
-
-               segment->total_size += ahslen;
-               segment->size += ahslen;
-               return 0;
-       }
-
-       /* We're done processing the header. See if we're doing
-        * header digests; if so, set up the recv_digest buffer
-        * and go back for more. */
-       if (conn->hdrdgst_en) {
-               if (segment->digest_len == 0) {
-                       /*
-                        * Even if we offload the digest processing we
-                        * splice it in so we can increment the skb/segment
-                        * counters in preparation for the data segment.
-                        */
-                       iscsi_tcp_segment_splice_digest(segment,
-                                                       segment->recv_digest);
-                       return 0;
-               }
-
-               if (!(conn->session->tt->caps & CAP_DIGEST_OFFLOAD)) {
-                       iscsi_tcp_dgst_header(&tcp_conn->rx_hash, hdr,
-                               segment->total_copied - ISCSI_DIGEST_SIZE,
-                               segment->digest);
-
-                       if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
-                               return ISCSI_ERR_HDR_DGST;
-               }
-       }
-
-       tcp_conn->in.hdr = hdr;
-       return iscsi_tcp_hdr_dissect(conn, hdr);
-}
-
-inline int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn)
-{
-       return tcp_conn->in.segment.done == iscsi_tcp_hdr_recv_done;
-}
-
-enum {
-       ISCSI_TCP_SEGMENT_DONE,         /* curr seg has been processed */
-       ISCSI_TCP_SKB_DONE,             /* skb is out of data */
-       ISCSI_TCP_CONN_ERR,             /* iscsi layer has fired a conn err */
-       ISCSI_TCP_SUSPENDED,            /* conn is suspended */
-};
-
-/**
- * iscsi_tcp_recv_skb - Process skb
- * @conn: iscsi connection
- * @skb: network buffer with header and/or data segment
- * @offset: offset in skb
- * @offload: bool indicating if transfer was offloaded
- */
-int iscsi_tcp_recv_skb(struct iscsi_conn *conn, struct sk_buff *skb,
-                      unsigned int offset, bool offloaded, int *status)
-{
-       struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct iscsi_segment *segment = &tcp_conn->in.segment;
-       struct skb_seq_state seq;
-       unsigned int consumed = 0;
-       int rc = 0;
-
-       debug_tcp("in %d bytes\n", skb->len - offset);
-
-       if (unlikely(conn->suspend_rx)) {
-               debug_tcp("conn %d Rx suspended!\n", conn->id);
-               *status = ISCSI_TCP_SUSPENDED;
-               return 0;
-       }
-
-       if (offloaded) {
-               segment->total_copied = segment->total_size;
-               goto segment_done;
-       }
-
-       skb_prepare_seq_read(skb, offset, skb->len, &seq);
-       while (1) {
-               unsigned int avail;
-               const u8 *ptr;
-
-               avail = skb_seq_read(consumed, &ptr, &seq);
-               if (avail == 0) {
-                       debug_tcp("no more data avail. Consumed %d\n",
-                                 consumed);
-                       *status = ISCSI_TCP_SKB_DONE;
-                       skb_abort_seq_read(&seq);
-                       goto skb_done;
-               }
-               BUG_ON(segment->copied >= segment->size);
-
-               debug_tcp("skb %p ptr=%p avail=%u\n", skb, ptr, avail);
-               rc = iscsi_tcp_segment_recv(tcp_conn, segment, ptr, avail);
-               BUG_ON(rc == 0);
-               consumed += rc;
-
-               if (segment->total_copied >= segment->total_size) {
-                       skb_abort_seq_read(&seq);
-                       goto segment_done;
-               }
-       }
-
-segment_done:
-       *status = ISCSI_TCP_SEGMENT_DONE;
-       debug_tcp("segment done\n");
-       rc = segment->done(tcp_conn, segment);
-       if (rc != 0) {
-               *status = ISCSI_TCP_CONN_ERR;
-               debug_tcp("Error receiving PDU, errno=%d\n", rc);
-               iscsi_conn_failure(conn, rc);
-               return 0;
-       }
-       /* The done() functions sets up the next segment. */
-
-skb_done:
-       conn->rxdata_octets += consumed;
-       return consumed;
-}
-EXPORT_SYMBOL_GPL(iscsi_tcp_recv_skb);
-
-/**
- * iscsi_tcp_recv - TCP receive in sendfile fashion
+ * iscsi_sw_tcp_recv - TCP receive in sendfile fashion
  * @rd_desc: read descriptor
  * @skb: socket buffer
  * @offset: offset in skb
  * @len: skb->len - offset
- **/
-static int
-iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
-              unsigned int offset, size_t len)
+ */
+static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
+                            unsigned int offset, size_t len)
 {
        struct iscsi_conn *conn = rd_desc->arg.data;
        unsigned int consumed, total_consumed = 0;
@@ -993,8 +90,7 @@ iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
        return total_consumed;
 }
 
-static void
-iscsi_tcp_data_ready(struct sock *sk, int flag)
+static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag)
 {
        struct iscsi_conn *conn = sk->sk_user_data;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
@@ -1010,7 +106,7 @@ iscsi_tcp_data_ready(struct sock *sk, int flag)
         */
        rd_desc.arg.data = conn;
        rd_desc.count = 1;
-       tcp_read_sock(sk, &rd_desc, iscsi_tcp_recv);
+       tcp_read_sock(sk, &rd_desc, iscsi_sw_tcp_recv);
 
        read_unlock(&sk->sk_callback_lock);
 
@@ -1019,10 +115,10 @@ iscsi_tcp_data_ready(struct sock *sk, int flag)
        iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
 }
 
-static void
-iscsi_tcp_state_change(struct sock *sk)
+static void iscsi_sw_tcp_state_change(struct sock *sk)
 {
        struct iscsi_tcp_conn *tcp_conn;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn;
        struct iscsi_conn *conn;
        struct iscsi_session *session;
        void (*old_state_change)(struct sock *);
@@ -1040,7 +136,8 @@ iscsi_tcp_state_change(struct sock *sk)
        }
 
        tcp_conn = conn->dd_data;
-       old_state_change = tcp_conn->old_state_change;
+       tcp_sw_conn = tcp_conn->dd_data;
+       old_state_change = tcp_sw_conn->old_state_change;
 
        read_unlock(&sk->sk_callback_lock);
 
@@ -1051,59 +148,122 @@ iscsi_tcp_state_change(struct sock *sk)
  * iscsi_write_space - Called when more output buffer space is available
  * @sk: socket space is available for
  **/
-static void iscsi_tcp_write_space(struct sock *sk)
+static void iscsi_sw_tcp_write_space(struct sock *sk)
 {
        struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 
-       tcp_conn->old_write_space(sk);
+       tcp_sw_conn->old_write_space(sk);
        debug_tcp("iscsi_write_space: cid %d\n", conn->id);
        scsi_queue_work(conn->session->host, &conn->xmitwork);
 }
 
-static void iscsi_tcp_conn_set_callbacks(struct iscsi_conn *conn)
+static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
 {
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct sock *sk = tcp_conn->sock->sk;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
+       struct sock *sk = tcp_sw_conn->sock->sk;
 
        /* assign new callbacks */
        write_lock_bh(&sk->sk_callback_lock);
        sk->sk_user_data = conn;
-       tcp_conn->old_data_ready = sk->sk_data_ready;
-       tcp_conn->old_state_change = sk->sk_state_change;
-       tcp_conn->old_write_space = sk->sk_write_space;
-       sk->sk_data_ready = iscsi_tcp_data_ready;
-       sk->sk_state_change = iscsi_tcp_state_change;
-       sk->sk_write_space = iscsi_tcp_write_space;
+       tcp_sw_conn->old_data_ready = sk->sk_data_ready;
+       tcp_sw_conn->old_state_change = sk->sk_state_change;
+       tcp_sw_conn->old_write_space = sk->sk_write_space;
+       sk->sk_data_ready = iscsi_sw_tcp_data_ready;
+       sk->sk_state_change = iscsi_sw_tcp_state_change;
+       sk->sk_write_space = iscsi_sw_tcp_write_space;
        write_unlock_bh(&sk->sk_callback_lock);
 }
 
-static void iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
+static void
+iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_sw_tcp_conn *tcp_sw_conn)
 {
-       struct sock *sk = tcp_conn->sock->sk;
+       struct sock *sk = tcp_sw_conn->sock->sk;
 
        /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
        write_lock_bh(&sk->sk_callback_lock);
        sk->sk_user_data    = NULL;
-       sk->sk_data_ready   = tcp_conn->old_data_ready;
-       sk->sk_state_change = tcp_conn->old_state_change;
-       sk->sk_write_space  = tcp_conn->old_write_space;
+       sk->sk_data_ready   = tcp_sw_conn->old_data_ready;
+       sk->sk_state_change = tcp_sw_conn->old_state_change;
+       sk->sk_write_space  = tcp_sw_conn->old_write_space;
        sk->sk_no_check  = 0;
        write_unlock_bh(&sk->sk_callback_lock);
 }
 
 /**
- * iscsi_tcp_xmit - TCP transmit
+ * iscsi_sw_tcp_xmit_segment - transmit segment
+ * @tcp_sw_conn: the iSCSI TCP connection
+ * @segment: the buffer to transmnit
+ *
+ * This function transmits as much of the buffer as
+ * the network layer will accept, and returns the number of
+ * bytes transmitted.
+ *
+ * If CRC hashing is enabled, the function will compute the
+ * hash as it goes. When the entire segment has been transmitted,
+ * it will retrieve the hash value and send it as well.
+ */
+static int iscsi_sw_tcp_xmit_segment(struct iscsi_sw_tcp_conn *tcp_sw_conn,
+                                    struct iscsi_segment *segment)
+{
+       struct socket *sk = tcp_sw_conn->sock;
+       unsigned int copied = 0;
+       int r = 0;
+
+       while (!iscsi_tcp_segment_done(segment, 0, r)) {
+               struct scatterlist *sg;
+               unsigned int offset, copy;
+               int flags = 0;
+
+               r = 0;
+               offset = segment->copied;
+               copy = segment->size - offset;
+
+               if (segment->total_copied + segment->size < segment->total_size)
+                       flags |= MSG_MORE;
+
+               /* Use sendpage if we can; else fall back to sendmsg */
+               if (!segment->data) {
+                       sg = segment->sg;
+                       offset += segment->sg_offset + sg->offset;
+                       r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset,
+                                                 copy, flags);
+               } else {
+                       struct msghdr msg = { .msg_flags = flags };
+                       struct kvec iov = {
+                               .iov_base = segment->data + offset,
+                               .iov_len = copy
+                       };
+
+                       r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
+               }
+
+               if (r < 0) {
+                       iscsi_tcp_segment_unmap(segment);
+                       if (copied || r == -EAGAIN)
+                               break;
+                       return r;
+               }
+               copied += r;
+       }
+       return copied;
+}
+
+/**
+ * iscsi_sw_tcp_xmit - TCP transmit
  **/
-static int iscsi_tcp_xmit(struct iscsi_conn *conn)
+static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
 {
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct iscsi_segment *segment = &tcp_conn->out.segment;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
+       struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
        unsigned int consumed = 0;
        int rc = 0;
 
        while (1) {
-               rc = iscsi_tcp_xmit_segment(tcp_conn, segment);
+               rc = iscsi_sw_tcp_xmit_segment(tcp_sw_conn, segment);
                if (rc < 0) {
                        rc = ISCSI_ERR_XMIT_FAILED;
                        goto error;
@@ -1138,22 +298,22 @@ error:
 /**
  * iscsi_tcp_xmit_qlen - return the number of bytes queued for xmit
  */
-static inline int
-iscsi_tcp_xmit_qlen(struct iscsi_conn *conn)
+static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
 {
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct iscsi_segment *segment = &tcp_conn->out.segment;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
+       struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
 
        return segment->total_copied - segment->total_size;
 }
 
-static int iscsi_tcp_flush(struct iscsi_task *task)
+static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
 {
        struct iscsi_conn *conn = task->conn;
        int rc;
 
-       while (iscsi_tcp_xmit_qlen(conn)) {
-               rc = iscsi_tcp_xmit(conn);
+       while (iscsi_sw_tcp_xmit_qlen(conn)) {
+               rc = iscsi_sw_tcp_xmit(conn);
                if (rc == 0)
                        return -EAGAIN;
                if (rc < 0)
@@ -1167,27 +327,31 @@ static int iscsi_tcp_flush(struct iscsi_task *task)
  * This is called when we're done sending the header.
  * Simply copy the data_segment to the send segment, and return.
  */
-static int
-iscsi_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
-                       struct iscsi_segment *segment)
+static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
+                                     struct iscsi_segment *segment)
 {
-       tcp_conn->out.segment = tcp_conn->out.data_segment;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
+
+       tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
        debug_tcp("Header done. Next segment size %u total_size %u\n",
-                 tcp_conn->out.segment.size, tcp_conn->out.segment.total_size);
+                 tcp_sw_conn->out.segment.size,
+                 tcp_sw_conn->out.segment.total_size);
        return 0;
 }
 
-static void
-iscsi_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, size_t hdrlen)
+static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
+                                      size_t hdrlen)
 {
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 
        debug_tcp("%s(%p%s)\n", __func__, tcp_conn,
                        conn->hdrdgst_en? ", digest enabled" : "");
 
        /* Clear the data segment - needs to be filled in by the
         * caller using iscsi_tcp_send_data_prep() */
-       memset(&tcp_conn->out.data_segment, 0, sizeof(struct iscsi_segment));
+       memset(&tcp_sw_conn->out.data_segment, 0,
+              sizeof(struct iscsi_segment));
 
        /* If header digest is enabled, compute the CRC and
         * place the digest into the same buffer. We make
@@ -1195,7 +359,7 @@ iscsi_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, size_t hdrlen)
         * sufficient room.
         */
        if (conn->hdrdgst_en) {
-               iscsi_tcp_dgst_header(&tcp_conn->tx_hash, hdr, hdrlen,
+               iscsi_tcp_dgst_header(&tcp_sw_conn->tx_hash, hdr, hdrlen,
                                      hdr + hdrlen);
                hdrlen += ISCSI_DIGEST_SIZE;
        }
@@ -1203,10 +367,10 @@ iscsi_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, size_t hdrlen)
        /* Remember header pointer for later, when we need
         * to decide whether there's a payload to go along
         * with the header. */
-       tcp_conn->out.hdr = hdr;
+       tcp_sw_conn->out.hdr = hdr;
 
-       iscsi_segment_init_linear(&tcp_conn->out.segment, hdr, hdrlen,
-                               iscsi_tcp_send_hdr_done, NULL);
+       iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
+                                 iscsi_sw_tcp_send_hdr_done, NULL);
 }
 
 /*
@@ -1215,11 +379,12 @@ iscsi_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr, size_t hdrlen)
  * of by the iscsi_segment routines.
  */
 static int
-iscsi_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
-                        unsigned int count, unsigned int offset,
-                        unsigned int len)
+iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
+                           unsigned int count, unsigned int offset,
+                           unsigned int len)
 {
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
        struct hash_desc *tx_hash = NULL;
        unsigned int hdr_spec_len;
 
@@ -1229,22 +394,23 @@ iscsi_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
 
        /* Make sure the datalen matches what the caller
           said he would send. */
-       hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
+       hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
        WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
 
        if (conn->datadgst_en)
-               tx_hash = &tcp_conn->tx_hash;
+               tx_hash = &tcp_sw_conn->tx_hash;
 
-       return iscsi_segment_seek_sg(&tcp_conn->out.data_segment,
-                                  sg, count, offset, len,
-                                  NULL, tx_hash);
+       return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
+                                    sg, count, offset, len,
+                                    NULL, tx_hash);
 }
 
 static void
-iscsi_tcp_send_linear_data_prepare(struct iscsi_conn *conn, void *data,
+iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
                                   size_t len)
 {
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
        struct hash_desc *tx_hash = NULL;
        unsigned int hdr_spec_len;
 
@@ -1253,34 +419,35 @@ iscsi_tcp_send_linear_data_prepare(struct iscsi_conn *conn, void *data,
 
        /* Make sure the datalen matches what the caller
           said he would send. */
-       hdr_spec_len = ntoh24(tcp_conn->out.hdr->dlength);
+       hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
        WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
 
        if (conn->datadgst_en)
-               tx_hash = &tcp_conn->tx_hash;
+               tx_hash = &tcp_sw_conn->tx_hash;
 
-       iscsi_segment_init_linear(&tcp_conn->out.data_segment,
+       iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
                                data, len, NULL, tx_hash);
 }
 
-static int iscsi_tcp_pdu_init(struct iscsi_task *task,
-                             unsigned int offset, unsigned int count)
+static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
+                                unsigned int offset, unsigned int count)
 {
        struct iscsi_conn *conn = task->conn;
        int err = 0;
 
-       iscsi_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
+       iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
 
        if (!count)
                return 0;
 
        if (!task->sc)
-               iscsi_tcp_send_linear_data_prepare(conn, task->data, count);
+               iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
        else {
                struct scsi_data_buffer *sdb = scsi_out(task->sc);
 
-               err = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
-                                              sdb->table.nents, offset, count);
+               err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
+                                                 sdb->table.nents, offset,
+                                                 count);
        }
 
        if (err) {
@@ -1290,251 +457,122 @@ static int iscsi_tcp_pdu_init(struct iscsi_task *task,
        return 0;
 }
 
-static int iscsi_tcp_pdu_alloc(struct iscsi_task *task)
-{
-       struct iscsi_tcp_task *tcp_task = task->dd_data;
-
-       task->hdr = &tcp_task->hdr.hdrbuf;
-       task->hdr_max = sizeof(tcp_task->hdr) - ISCSI_DIGEST_SIZE;
-       return 0;
-}
-
-/**
- * iscsi_tcp_task - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
- * @conn: iscsi connection
- * @task: scsi command task
- * @sc: scsi command
- **/
-static int iscsi_tcp_task_init(struct iscsi_task *task)
+static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task)
 {
        struct iscsi_tcp_task *tcp_task = task->dd_data;
-       struct iscsi_conn *conn = task->conn;
-       struct scsi_cmnd *sc = task->sc;
-       int err;
 
-       if (!sc) {
-               /*
-                * mgmt tasks do not have a scatterlist since they come
-                * in from the iscsi interface.
-                */
-               debug_scsi("mtask deq [cid %d itt 0x%x]\n", conn->id,
-                          task->itt);
-
-               return conn->session->tt->init_pdu(task, 0, task->data_count);
-       }
-
-       BUG_ON(__kfifo_len(tcp_task->r2tqueue));
-       tcp_task->exp_datasn = 0;
-
-       /* Prepare PDU, optionally w/ immediate data */
-       debug_scsi("task deq [cid %d itt 0x%x imm %d unsol %d]\n",
-                   conn->id, task->itt, task->imm_count,
-                   task->unsol_r2t.data_length);
-
-       err = conn->session->tt->init_pdu(task, 0, task->imm_count);
-       if (err)
-               return err;
-       task->imm_count = 0;
+       task->hdr = task->dd_data + sizeof(*tcp_task);
+       task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
        return 0;
 }
 
-static struct iscsi_r2t_info *iscsi_tcp_get_curr_r2t(struct iscsi_task *task)
-{
-       struct iscsi_session *session = task->conn->session;
-       struct iscsi_tcp_task *tcp_task = task->dd_data;
-       struct iscsi_r2t_info *r2t = NULL;
-
-       if (iscsi_task_has_unsol_data(task))
-               r2t = &task->unsol_r2t;
-       else {
-               spin_lock_bh(&session->lock);
-               if (tcp_task->r2t) {
-                       r2t = tcp_task->r2t;
-                       /* Continue with this R2T? */
-                       if (r2t->data_length <= r2t->sent) {
-                               debug_scsi("  done with r2t %p\n", r2t);
-                               __kfifo_put(tcp_task->r2tpool.queue,
-                                           (void *)&tcp_task->r2t,
-                                           sizeof(void *));
-                               tcp_task->r2t = r2t = NULL;
-                       }
-               }
-
-               if (r2t == NULL) {
-                       __kfifo_get(tcp_task->r2tqueue,
-                                   (void *)&tcp_task->r2t, sizeof(void *));
-                       r2t = tcp_task->r2t;
-               }
-               spin_unlock_bh(&session->lock);
-       }
-
-       return r2t;
-}
-
-/*
- * iscsi_tcp_task_xmit - xmit normal PDU task
- * @task: iscsi command task
- *
- * We're expected to return 0 when everything was transmitted succesfully,
- * -EAGAIN if there's still data in the queue, or != 0 for any other kind
- * of error.
- */
-static int iscsi_tcp_task_xmit(struct iscsi_task *task)
-{
-       struct iscsi_conn *conn = task->conn;
-       struct iscsi_session *session = conn->session;
-       struct iscsi_r2t_info *r2t;
-       int rc = 0;
-
-flush:
-       /* Flush any pending data first. */
-       rc = session->tt->xmit_pdu(task);
-       if (rc < 0)
-               return rc;
-
-       /* mgmt command */
-       if (!task->sc) {
-               if (task->hdr->itt == RESERVED_ITT)
-                       iscsi_put_task(task);
-               return 0;
-       }
-
-       /* Are we done already? */
-       if (task->sc->sc_data_direction != DMA_TO_DEVICE)
-               return 0;
-
-       r2t = iscsi_tcp_get_curr_r2t(task);
-       if (r2t == NULL) {
-               /* Waiting for more R2Ts to arrive. */
-               debug_tcp("no R2Ts yet\n");
-               return 0;
-       }
-
-       rc = conn->session->tt->alloc_pdu(task);
-       if (rc)
-               return rc;
-       iscsi_prep_data_out_pdu(task, r2t, (struct iscsi_data *) task->hdr);
-
-       debug_scsi("sol dout %p [dsn %d itt 0x%x doff %d dlen %d]\n",
-                  r2t, r2t->datasn - 1, task->hdr->itt,
-                  r2t->data_offset + r2t->sent, r2t->data_count);
-
-       rc = conn->session->tt->init_pdu(task, r2t->data_offset + r2t->sent,
-                                        r2t->data_count);
-       if (rc)
-               return rc;
-       r2t->sent += r2t->data_count;
-       goto flush;
-}
-
 static struct iscsi_cls_conn *
-iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
+iscsi_sw_tcp_conn_create(struct iscsi_cls_session *cls_session,
+                        uint32_t conn_idx)
 {
        struct iscsi_conn *conn;
        struct iscsi_cls_conn *cls_conn;
        struct iscsi_tcp_conn *tcp_conn;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn;
 
-       cls_conn = iscsi_conn_setup(cls_session, sizeof(*tcp_conn), conn_idx);
+       cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
+                                       conn_idx);
        if (!cls_conn)
                return NULL;
        conn = cls_conn->dd_data;
-       /*
-        * due to strange issues with iser these are not set
-        * in iscsi_conn_setup
-        */
-       conn->max_recv_dlength = ISCSI_DEF_MAX_RECV_SEG_LEN;
-
        tcp_conn = conn->dd_data;
-       tcp_conn->iscsi_conn = conn;
+       tcp_sw_conn = tcp_conn->dd_data;
 
-       tcp_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
-                                                 CRYPTO_ALG_ASYNC);
-       tcp_conn->tx_hash.flags = 0;
-       if (IS_ERR(tcp_conn->tx_hash.tfm))
+       tcp_sw_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
+                                                    CRYPTO_ALG_ASYNC);
+       tcp_sw_conn->tx_hash.flags = 0;
+       if (IS_ERR(tcp_sw_conn->tx_hash.tfm))
                goto free_conn;
 
-       tcp_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
-                                                 CRYPTO_ALG_ASYNC);
-       tcp_conn->rx_hash.flags = 0;
-       if (IS_ERR(tcp_conn->rx_hash.tfm))
+       tcp_sw_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
+                                                    CRYPTO_ALG_ASYNC);
+       tcp_sw_conn->rx_hash.flags = 0;
+       if (IS_ERR(tcp_sw_conn->rx_hash.tfm))
                goto free_tx_tfm;
+       tcp_conn->rx_hash = &tcp_sw_conn->rx_hash;
 
        return cls_conn;
 
 free_tx_tfm:
-       crypto_free_hash(tcp_conn->tx_hash.tfm);
+       crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
 free_conn:
        iscsi_conn_printk(KERN_ERR, conn,
                          "Could not create connection due to crc32c "
                          "loading error. Make sure the crc32c "
                          "module is built as a module or into the "
                          "kernel\n");
-       iscsi_conn_teardown(cls_conn);
+       iscsi_tcp_conn_teardown(cls_conn);
        return NULL;
 }
 
-static void
-iscsi_tcp_release_conn(struct iscsi_conn *conn)
+static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
 {
        struct iscsi_session *session = conn->session;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
-       struct socket *sock = tcp_conn->sock;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
+       struct socket *sock = tcp_sw_conn->sock;
 
        if (!sock)
                return;
 
        sock_hold(sock->sk);
-       iscsi_conn_restore_callbacks(tcp_conn);
+       iscsi_sw_tcp_conn_restore_callbacks(tcp_sw_conn);
        sock_put(sock->sk);
 
        spin_lock_bh(&session->lock);
-       tcp_conn->sock = NULL;
+       tcp_sw_conn->sock = NULL;
        spin_unlock_bh(&session->lock);
        sockfd_put(sock);
 }
 
-static void
-iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
+static void iscsi_sw_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
 {
        struct iscsi_conn *conn = cls_conn->dd_data;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 
-       iscsi_tcp_release_conn(conn);
+       iscsi_sw_tcp_release_conn(conn);
 
-       if (tcp_conn->tx_hash.tfm)
-               crypto_free_hash(tcp_conn->tx_hash.tfm);
-       if (tcp_conn->rx_hash.tfm)
-               crypto_free_hash(tcp_conn->rx_hash.tfm);
+       if (tcp_sw_conn->tx_hash.tfm)
+               crypto_free_hash(tcp_sw_conn->tx_hash.tfm);
+       if (tcp_sw_conn->rx_hash.tfm)
+               crypto_free_hash(tcp_sw_conn->rx_hash.tfm);
 
-       iscsi_conn_teardown(cls_conn);
+       iscsi_tcp_conn_teardown(cls_conn);
 }
 
-static void
-iscsi_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
+static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 {
        struct iscsi_conn *conn = cls_conn->dd_data;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 
        /* userspace may have goofed up and not bound us */
-       if (!tcp_conn->sock)
+       if (!tcp_sw_conn->sock)
                return;
        /*
         * Make sure our recv side is stopped.
         * Older tools called conn stop before ep_disconnect
         * so IO could still be coming in.
         */
-       write_lock_bh(&tcp_conn->sock->sk->sk_callback_lock);
+       write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
        set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
-       write_unlock_bh(&tcp_conn->sock->sk->sk_callback_lock);
+       write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
 
        iscsi_conn_stop(cls_conn, flag);
-       iscsi_tcp_release_conn(conn);
+       iscsi_sw_tcp_release_conn(conn);
 }
 
-static int iscsi_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
-                             char *buf, int *port,
-                             int (*getname)(struct socket *, struct sockaddr *,
-                                       int *addrlen))
+static int iscsi_sw_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
+                                char *buf, int *port,
+                                int (*getname)(struct socket *,
+                                               struct sockaddr *,
+                                               int *addrlen))
 {
        struct sockaddr_storage *addr;
        struct sockaddr_in6 *sin6;
@@ -1572,14 +610,15 @@ free_addr:
 }
 
 static int
-iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
-                   struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
-                   int is_leading)
+iscsi_sw_tcp_conn_bind(struct iscsi_cls_session *cls_session,
+                      struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
+                      int is_leading)
 {
        struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
        struct iscsi_host *ihost = shost_priv(shost);
        struct iscsi_conn *conn = cls_conn->dd_data;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
        struct sock *sk;
        struct socket *sock;
        int err;
@@ -1596,13 +635,13 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
         * userspace may still want to query the values since we will
         * be using them for the reconnect
         */
-       err = iscsi_tcp_get_addr(conn, sock, conn->portal_address,
-                                &conn->portal_port, kernel_getpeername);
+       err = iscsi_sw_tcp_get_addr(conn, sock, conn->portal_address,
+                                   &conn->portal_port, kernel_getpeername);
        if (err)
                goto free_socket;
 
-       err = iscsi_tcp_get_addr(conn, sock, ihost->local_address,
-                               &ihost->local_port, kernel_getsockname);
+       err = iscsi_sw_tcp_get_addr(conn, sock, ihost->local_address,
+                                   &ihost->local_port, kernel_getsockname);
        if (err)
                goto free_socket;
 
@@ -1611,7 +650,7 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
                goto free_socket;
 
        /* bind iSCSI connection and socket */
-       tcp_conn->sock = sock;
+       tcp_sw_conn->sock = sock;
 
        /* setup Socket parameters */
        sk = sock->sk;
@@ -1619,8 +658,8 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
        sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
        sk->sk_allocation = GFP_ATOMIC;
 
-       iscsi_tcp_conn_set_callbacks(conn);
-       tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
+       iscsi_sw_tcp_conn_set_callbacks(conn);
+       tcp_sw_conn->sendpage = tcp_sw_conn->sock->ops->sendpage;
        /*
         * set receive state machine into initial state
         */
@@ -1632,75 +671,14 @@ free_socket:
        return err;
 }
 
-static int
-iscsi_r2tpool_alloc(struct iscsi_session *session)
-{
-       int i;
-       int cmd_i;
-
-       /*
-        * initialize per-task: R2T pool and xmit queue
-        */
-       for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
-               struct iscsi_task *task = session->cmds[cmd_i];
-               struct iscsi_tcp_task *tcp_task = task->dd_data;
-
-               /*
-                * pre-allocated x2 as much r2ts to handle race when
-                * target acks DataOut faster than we data_xmit() queues
-                * could replenish r2tqueue.
-                */
-
-               /* R2T pool */
-               if (iscsi_pool_init(&tcp_task->r2tpool,
-                                   session->max_r2t * 2, NULL,
-                                   sizeof(struct iscsi_r2t_info))) {
-                       goto r2t_alloc_fail;
-               }
-
-               /* R2T xmit queue */
-               tcp_task->r2tqueue = kfifo_alloc(
-                     session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
-               if (tcp_task->r2tqueue == ERR_PTR(-ENOMEM)) {
-                       iscsi_pool_free(&tcp_task->r2tpool);
-                       goto r2t_alloc_fail;
-               }
-       }
-
-       return 0;
-
-r2t_alloc_fail:
-       for (i = 0; i < cmd_i; i++) {
-               struct iscsi_task *task = session->cmds[i];
-               struct iscsi_tcp_task *tcp_task = task->dd_data;
-
-               kfifo_free(tcp_task->r2tqueue);
-               iscsi_pool_free(&tcp_task->r2tpool);
-       }
-       return -ENOMEM;
-}
-
-static void
-iscsi_r2tpool_free(struct iscsi_session *session)
-{
-       int i;
-
-       for (i = 0; i < session->cmds_max; i++) {
-               struct iscsi_task *task = session->cmds[i];
-               struct iscsi_tcp_task *tcp_task = task->dd_data;
-
-               kfifo_free(tcp_task->r2tqueue);
-               iscsi_pool_free(&tcp_task->r2tpool);
-       }
-}
-
-static int
-iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
-                    char *buf, int buflen)
+static int iscsi_sw_tcp_conn_set_param(struct iscsi_cls_conn *cls_conn,
+                                      enum iscsi_param param, char *buf,
+                                      int buflen)
 {
        struct iscsi_conn *conn = cls_conn->dd_data;
        struct iscsi_session *session = conn->session;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
        int value;
 
        switch(param) {
@@ -1709,8 +687,8 @@ iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
                break;
        case ISCSI_PARAM_DATADGST_EN:
                iscsi_set_param(cls_conn, param, buf, buflen);
-               tcp_conn->sendpage = conn->datadgst_en ?
-                       sock_no_sendpage : tcp_conn->sock->ops->sendpage;
+               tcp_sw_conn->sendpage = conn->datadgst_en ?
+                       sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
                break;
        case ISCSI_PARAM_MAX_R2T:
                sscanf(buf, "%d", &value);
@@ -1718,9 +696,9 @@ iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
                        return -EINVAL;
                if (session->max_r2t == value)
                        break;
-               iscsi_r2tpool_free(session);
+               iscsi_tcp_r2tpool_free(session);
                iscsi_set_param(cls_conn, param, buf, buflen);
-               if (iscsi_r2tpool_alloc(session))
+               if (iscsi_tcp_r2tpool_alloc(session))
                        return -ENOMEM;
                break;
        default:
@@ -1730,9 +708,8 @@ iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
        return 0;
 }
 
-static int
-iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
-                        enum iscsi_param param, char *buf)
+static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
+                                      enum iscsi_param param, char *buf)
 {
        struct iscsi_conn *conn = cls_conn->dd_data;
        int len;
@@ -1756,33 +733,28 @@ iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
 }
 
 static void
-iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
+iscsi_sw_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
+                           struct iscsi_stats *stats)
 {
        struct iscsi_conn *conn = cls_conn->dd_data;
        struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
+       struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
 
-       stats->txdata_octets = conn->txdata_octets;
-       stats->rxdata_octets = conn->rxdata_octets;
-       stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
-       stats->dataout_pdus = conn->dataout_pdus_cnt;
-       stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
-       stats->datain_pdus = conn->datain_pdus_cnt;
-       stats->r2t_pdus = conn->r2t_pdus_cnt;
-       stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
-       stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
        stats->custom_length = 3;
        strcpy(stats->custom[0].desc, "tx_sendpage_failures");
-       stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
+       stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
        strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
-       stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
+       stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
        strcpy(stats->custom[2].desc, "eh_abort_cnt");
        stats->custom[2].value = conn->eh_abort_cnt;
+
+       iscsi_tcp_conn_get_stats(cls_conn, stats);
 }
 
 static struct iscsi_cls_session *
-iscsi_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
-                        uint16_t qdepth, uint32_t initial_cmdsn,
-                        uint32_t *hostno)
+iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
+                           uint16_t qdepth, uint32_t initial_cmdsn,
+                           uint32_t *hostno)
 {
        struct iscsi_cls_session *cls_session;
        struct iscsi_session *session;
@@ -1793,10 +765,10 @@ iscsi_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
                return NULL;
        }
 
-       shost = iscsi_host_alloc(&iscsi_sht, 0, qdepth);
+       shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, qdepth);
        if (!shost)
                return NULL;
-       shost->transportt = iscsi_tcp_scsi_transport;
+       shost->transportt = iscsi_sw_tcp_scsi_transport;
        shost->max_lun = iscsi_max_lun;
        shost->max_id = 0;
        shost->max_channel = 0;
@@ -1806,15 +778,17 @@ iscsi_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
                goto free_host;
        *hostno = shost->host_no;
 
-       cls_session = iscsi_session_setup(&iscsi_tcp_transport, shost, cmds_max,
-                                         sizeof(struct iscsi_tcp_task),
+       cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
+                                         cmds_max,
+                                         sizeof(struct iscsi_tcp_task) +
+                                         sizeof(struct iscsi_sw_tcp_hdrbuf),
                                          initial_cmdsn, 0);
        if (!cls_session)
                goto remove_host;
        session = cls_session->dd_data;
 
        shost->can_queue = session->scsi_cmds_max;
-       if (iscsi_r2tpool_alloc(session))
+       if (iscsi_tcp_r2tpool_alloc(session))
                goto remove_session;
        return cls_session;
 
@@ -1827,25 +801,25 @@ free_host:
        return NULL;
 }
 
-static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
+static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
 {
        struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 
-       iscsi_r2tpool_free(cls_session->dd_data);
+       iscsi_tcp_r2tpool_free(cls_session->dd_data);
        iscsi_session_teardown(cls_session);
 
        iscsi_host_remove(shost);
        iscsi_host_free(shost);
 }
 
-static int iscsi_tcp_slave_configure(struct scsi_device *sdev)
+static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
 {
        blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
        blk_queue_dma_alignment(sdev->request_queue, 0);
        return 0;
 }
 
-static struct scsi_host_template iscsi_sht = {
+static struct scsi_host_template iscsi_sw_tcp_sht = {
        .module                 = THIS_MODULE,
        .name                   = "iSCSI Initiator over TCP/IP",
        .queuecommand           = iscsi_queuecommand,
@@ -1858,12 +832,12 @@ static struct scsi_host_template iscsi_sht = {
        .eh_device_reset_handler= iscsi_eh_device_reset,
        .eh_target_reset_handler= iscsi_eh_target_reset,
        .use_clustering         = DISABLE_CLUSTERING,
-       .slave_configure        = iscsi_tcp_slave_configure,
+       .slave_configure        = iscsi_sw_tcp_slave_configure,
        .proc_name              = "iscsi_tcp",
        .this_id                = -1,
 };
 
-static struct iscsi_transport iscsi_tcp_transport = {
+static struct iscsi_transport iscsi_sw_tcp_transport = {
        .owner                  = THIS_MODULE,
        .name                   = "tcp",
        .caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
@@ -1896,37 +870,36 @@ static struct iscsi_transport iscsi_tcp_transport = {
                                  ISCSI_HOST_INITIATOR_NAME |
                                  ISCSI_HOST_NETDEV_NAME,
        /* session management */
-       .create_session         = iscsi_tcp_session_create,
-       .destroy_session        = iscsi_tcp_session_destroy,
+       .create_session         = iscsi_sw_tcp_session_create,
+       .destroy_session        = iscsi_sw_tcp_session_destroy,
        /* connection management */
-       .create_conn            = iscsi_tcp_conn_create,
-       .bind_conn              = iscsi_tcp_conn_bind,
-       .destroy_conn           = iscsi_tcp_conn_destroy,
-       .set_param              = iscsi_conn_set_param,
-       .get_conn_param         = iscsi_tcp_conn_get_param,
+       .create_conn            = iscsi_sw_tcp_conn_create,
+       .bind_conn              = iscsi_sw_tcp_conn_bind,
+       .destroy_conn           = iscsi_sw_tcp_conn_destroy,
+       .set_param              = iscsi_sw_tcp_conn_set_param,
+       .get_conn_param         = iscsi_sw_tcp_conn_get_param,
        .get_session_param      = iscsi_session_get_param,
        .start_conn             = iscsi_conn_start,
-       .stop_conn              = iscsi_tcp_conn_stop,
+       .stop_conn              = iscsi_sw_tcp_conn_stop,
        /* iscsi host params */
        .get_host_param         = iscsi_host_get_param,
        .set_host_param         = iscsi_host_set_param,
        /* IO */
        .send_pdu               = iscsi_conn_send_pdu,
-       .get_stats              = iscsi_conn_get_stats,
+       .get_stats              = iscsi_sw_tcp_conn_get_stats,
        /* iscsi task/cmd helpers */
        .init_task              = iscsi_tcp_task_init,
        .xmit_task              = iscsi_tcp_task_xmit,
        .cleanup_task           = iscsi_tcp_cleanup_task,
        /* low level pdu helpers */
-       .xmit_pdu               = iscsi_tcp_flush,
-       .init_pdu               = iscsi_tcp_pdu_init,
-       .alloc_pdu              = iscsi_tcp_pdu_alloc,
+       .xmit_pdu               = iscsi_sw_tcp_pdu_xmit,
+       .init_pdu               = iscsi_sw_tcp_pdu_init,
+       .alloc_pdu              = iscsi_sw_tcp_pdu_alloc,
        /* recovery */
        .session_recovery_timedout = iscsi_session_recovery_timedout,
 };
 
-static int __init
-iscsi_tcp_init(void)
+static int __init iscsi_sw_tcp_init(void)
 {
        if (iscsi_max_lun < 1) {
                printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
@@ -1934,19 +907,18 @@ iscsi_tcp_init(void)
                return -EINVAL;
        }
 
-       iscsi_tcp_scsi_transport = iscsi_register_transport(
-                                                       &iscsi_tcp_transport);
-       if (!iscsi_tcp_scsi_transport)
+       iscsi_sw_tcp_scsi_transport = iscsi_register_transport(
+                                               &iscsi_sw_tcp_transport);
+       if (!iscsi_sw_tcp_scsi_transport)
                return -ENODEV;
 
        return 0;
 }
 
-static void __exit
-iscsi_tcp_exit(void)
+static void __exit iscsi_sw_tcp_exit(void)
 {
-       iscsi_unregister_transport(&iscsi_tcp_transport);
+       iscsi_unregister_transport(&iscsi_sw_tcp_transport);
 }
 
-module_init(iscsi_tcp_init);
-module_exit(iscsi_tcp_exit);
+module_init(iscsi_sw_tcp_init);
+module_exit(iscsi_sw_tcp_exit);
index 0ed4773..ca6b7bc 100644 (file)
  * See the file COPYING included with this distribution for more details.
  */
 
-#ifndef ISCSI_TCP_H
-#define ISCSI_TCP_H
+#ifndef ISCSI_SW_TCP_H
+#define ISCSI_SW_TCP_H
 
 #include <scsi/libiscsi.h>
+#include <scsi/libiscsi_tcp.h>
 
-struct crypto_hash;
 struct socket;
 struct iscsi_tcp_conn;
-struct iscsi_segment;
-
-typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *,
-                                   struct iscsi_segment *);
-
-struct iscsi_segment {
-       unsigned char           *data;
-       unsigned int            size;
-       unsigned int            copied;
-       unsigned int            total_size;
-       unsigned int            total_copied;
-
-       struct hash_desc        *hash;
-       unsigned char           recv_digest[ISCSI_DIGEST_SIZE];
-       unsigned char           digest[ISCSI_DIGEST_SIZE];
-       unsigned int            digest_len;
-
-       struct scatterlist      *sg;
-       void                    *sg_mapped;
-       unsigned int            sg_offset;
-
-       iscsi_segment_done_fn_t *done;
-};
-
-/* Socket connection recieve helper */
-struct iscsi_tcp_recv {
-       struct iscsi_hdr        *hdr;
-       struct iscsi_segment    segment;
-
-       /* Allocate buffer for BHS + AHS */
-       uint32_t                hdr_buf[64];
-
-       /* copied and flipped values */
-       int                     datalen;
-};
 
 /* Socket connection send helper */
-struct iscsi_tcp_send {
+struct iscsi_sw_tcp_send {
        struct iscsi_hdr        *hdr;
        struct iscsi_segment    segment;
        struct iscsi_segment    data_segment;
 };
 
-struct iscsi_tcp_conn {
+struct iscsi_sw_tcp_conn {
        struct iscsi_conn       *iscsi_conn;
        struct socket           *sock;
-       int                     stop_stage;     /* conn_stop() flag: *
-                                                * stop to recover,  *
-                                                * stop to terminate */
-       /* control data */
-       struct iscsi_tcp_recv   in;             /* TCP receive context */
-       struct iscsi_tcp_send   out;            /* TCP send context */
 
+       struct iscsi_sw_tcp_send out;
        /* old values for socket callbacks */
        void                    (*old_data_ready)(struct sock *, int);
        void                    (*old_state_change)(struct sock *);
@@ -93,24 +53,13 @@ struct iscsi_tcp_conn {
        uint32_t                sendpage_failures_cnt;
        uint32_t                discontiguous_hdr_cnt;
 
-       int                     error;
-
        ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
 };
 
-struct iscsi_tcp_task {
-       struct iscsi_hdr_buff {
-               struct iscsi_hdr        hdrbuf;
-               char                    hdrextbuf[ISCSI_MAX_AHS_SIZE +
+struct iscsi_sw_tcp_hdrbuf {
+       struct iscsi_hdr        hdrbuf;
+       char                    hdrextbuf[ISCSI_MAX_AHS_SIZE +
                                                  ISCSI_DIGEST_SIZE];
-       } hdr;
-
-       int                     sent;
-       uint32_t                exp_datasn;     /* expected target's R2TSN/DataSN */
-       int                     data_offset;
-       struct iscsi_r2t_info   *r2t;           /* in progress solict R2T */
-       struct iscsi_pool       r2tpool;
-       struct kfifo            *r2tqueue;
 };
 
-#endif /* ISCSI_H */
+#endif /* ISCSI_SW_TCP_H */