+++ /dev/null
-/*
- * cxgb3i_pdu.c: Chelsio S3xx iSCSI driver.
- *
- * Copyright (c) 2008 Chelsio Communications, Inc.
- * Copyright (c) 2008 Mike Christie
- * Copyright (c) 2008 Red Hat, Inc. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation.
- *
- * Written by: Karen Xie (kxie@chelsio.com)
- */
-
-#include <linux/slab.h>
-#include <linux/skbuff.h>
-#include <linux/crypto.h>
-#include <scsi/scsi_cmnd.h>
-#include <scsi/scsi_host.h>
-
-#include "cxgb3i.h"
-#include "cxgb3i_pdu.h"
-
-#ifdef __DEBUG_CXGB3I_RX__
-#define cxgb3i_rx_debug cxgb3i_log_debug
-#else
-#define cxgb3i_rx_debug(fmt...)
-#endif
-
-#ifdef __DEBUG_CXGB3I_TX__
-#define cxgb3i_tx_debug cxgb3i_log_debug
-#else
-#define cxgb3i_tx_debug(fmt...)
-#endif
-
-/* always allocate rooms for AHS */
-#define SKB_TX_PDU_HEADER_LEN \
- (sizeof(struct iscsi_hdr) + ISCSI_MAX_AHS_SIZE)
-static unsigned int skb_extra_headroom;
-static struct page *pad_page;
-
-/*
- * pdu receive, interact with libiscsi_tcp
- */
-static inline int read_pdu_skb(struct iscsi_conn *conn, struct sk_buff *skb,
- unsigned int offset, int offloaded)
-{
- int status = 0;
- int bytes_read;
-
- bytes_read = iscsi_tcp_recv_skb(conn, skb, offset, offloaded, &status);
- switch (status) {
- case ISCSI_TCP_CONN_ERR:
- return -EIO;
- case ISCSI_TCP_SUSPENDED:
- /* no transfer - just have caller flush queue */
- return bytes_read;
- case ISCSI_TCP_SKB_DONE:
- /*
- * pdus should always fit in the skb and we should get
- * segment done notifcation.
- */
- iscsi_conn_printk(KERN_ERR, conn, "Invalid pdu or skb.");
- return -EFAULT;
- case ISCSI_TCP_SEGMENT_DONE:
- return bytes_read;
- default:
- iscsi_conn_printk(KERN_ERR, conn, "Invalid iscsi_tcp_recv_skb "
- "status %d\n", status);
- return -EINVAL;
- }
-}
-
-static int cxgb3i_conn_read_pdu_skb(struct iscsi_conn *conn,
- struct sk_buff *skb)
-{
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- bool offloaded = 0;
- unsigned int offset;
- int rc;
-
- cxgb3i_rx_debug("conn 0x%p, skb 0x%p, len %u, flag 0x%x.\n",
- conn, skb, skb->len, skb_ulp_mode(skb));
-
- if (!iscsi_tcp_recv_segment_is_hdr(tcp_conn)) {
- iscsi_conn_failure(conn, ISCSI_ERR_PROTO);
- return -EIO;
- }
-
- if (conn->hdrdgst_en && (skb_ulp_mode(skb) & ULP2_FLAG_HCRC_ERROR)) {
- iscsi_conn_failure(conn, ISCSI_ERR_HDR_DGST);
- return -EIO;
- }
-
- if (conn->datadgst_en && (skb_ulp_mode(skb) & ULP2_FLAG_DCRC_ERROR)) {
- iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
- return -EIO;
- }
-
- /* iscsi hdr */
- rc = read_pdu_skb(conn, skb, 0, 0);
- if (rc <= 0)
- return rc;
-
- if (iscsi_tcp_recv_segment_is_hdr(tcp_conn))
- return 0;
-
- offset = rc;
- if (conn->hdrdgst_en)
- offset += ISCSI_DIGEST_SIZE;
-
- /* iscsi data */
- if (skb_ulp_mode(skb) & ULP2_FLAG_DATA_DDPED) {
- cxgb3i_rx_debug("skb 0x%p, opcode 0x%x, data %u, ddp'ed, "
- "itt 0x%x.\n",
- skb,
- tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK,
- tcp_conn->in.datalen,
- ntohl(tcp_conn->in.hdr->itt));
- offloaded = 1;
- } else {
- cxgb3i_rx_debug("skb 0x%p, opcode 0x%x, data %u, NOT ddp'ed, "
- "itt 0x%x.\n",
- skb,
- tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK,
- tcp_conn->in.datalen,
- ntohl(tcp_conn->in.hdr->itt));
- offset += sizeof(struct cpl_iscsi_hdr_norss);
- }
-
- rc = read_pdu_skb(conn, skb, offset, offloaded);
- if (rc < 0)
- return rc;
- else
- return 0;
-}
-
-/*
- * pdu transmit, interact with libiscsi_tcp
- */
-static inline void tx_skb_setmode(struct sk_buff *skb, int hcrc, int dcrc)
-{
- u8 submode = 0;
-
- if (hcrc)
- submode |= 1;
- if (dcrc)
- submode |= 2;
- skb_ulp_mode(skb) = (ULP_MODE_ISCSI << 4) | submode;
-}
-
-void cxgb3i_conn_cleanup_task(struct iscsi_task *task)
-{
- struct cxgb3i_task_data *tdata = task->dd_data +
- sizeof(struct iscsi_tcp_task);
-
- /* never reached the xmit task callout */
- if (tdata->skb)
- __kfree_skb(tdata->skb);
- memset(tdata, 0, sizeof(struct cxgb3i_task_data));
-
- /* MNC - Do we need a check in case this is called but
- * cxgb3i_conn_alloc_pdu has never been called on the task */
- cxgb3i_release_itt(task, task->hdr_itt);
- iscsi_tcp_cleanup_task(task);
-}
-
-static int sgl_seek_offset(struct scatterlist *sgl, unsigned int sgcnt,
- unsigned int offset, unsigned int *off,
- struct scatterlist **sgp)
-{
- int i;
- struct scatterlist *sg;
-
- for_each_sg(sgl, sg, sgcnt, i) {
- if (offset < sg->length) {
- *off = offset;
- *sgp = sg;
- return 0;
- }
- offset -= sg->length;
- }
- return -EFAULT;
-}
-
-static int sgl_read_to_frags(struct scatterlist *sg, unsigned int sgoffset,
- unsigned int dlen, skb_frag_t *frags,
- int frag_max)
-{
- unsigned int datalen = dlen;
- unsigned int sglen = sg->length - sgoffset;
- struct page *page = sg_page(sg);
- int i;
-
- i = 0;
- do {
- unsigned int copy;
-
- if (!sglen) {
- sg = sg_next(sg);
- if (!sg) {
- cxgb3i_log_error("%s, sg NULL, len %u/%u.\n",
- __func__, datalen, dlen);
- return -EINVAL;
- }
- sgoffset = 0;
- sglen = sg->length;
- page = sg_page(sg);
-
- }
- copy = min(datalen, sglen);
- if (i && page == frags[i - 1].page &&
- sgoffset + sg->offset ==
- frags[i - 1].page_offset + frags[i - 1].size) {
- frags[i - 1].size += copy;
- } else {
- if (i >= frag_max) {
- cxgb3i_log_error("%s, too many pages %u, "
- "dlen %u.\n", __func__,
- frag_max, dlen);
- return -EINVAL;
- }
-
- frags[i].page = page;
- frags[i].page_offset = sg->offset + sgoffset;
- frags[i].size = copy;
- i++;
- }
- datalen -= copy;
- sgoffset += copy;
- sglen -= copy;
- } while (datalen);
-
- return i;
-}
-
-int cxgb3i_conn_alloc_pdu(struct iscsi_task *task, u8 opcode)
-{
- struct iscsi_conn *conn = task->conn;
- struct iscsi_tcp_task *tcp_task = task->dd_data;
- struct cxgb3i_task_data *tdata = task->dd_data + sizeof(*tcp_task);
- struct scsi_cmnd *sc = task->sc;
- int headroom = SKB_TX_PDU_HEADER_LEN;
-
- tcp_task->dd_data = tdata;
- task->hdr = NULL;
-
- /* write command, need to send data pdus */
- if (skb_extra_headroom && (opcode == ISCSI_OP_SCSI_DATA_OUT ||
- (opcode == ISCSI_OP_SCSI_CMD &&
- (scsi_bidi_cmnd(sc) || sc->sc_data_direction == DMA_TO_DEVICE))))
- headroom += min(skb_extra_headroom, conn->max_xmit_dlength);
-
- tdata->skb = alloc_skb(TX_HEADER_LEN + headroom, GFP_ATOMIC);
- if (!tdata->skb)
- return -ENOMEM;
- skb_reserve(tdata->skb, TX_HEADER_LEN);
-
- cxgb3i_tx_debug("task 0x%p, opcode 0x%x, skb 0x%p.\n",
- task, opcode, tdata->skb);
-
- task->hdr = (struct iscsi_hdr *)tdata->skb->data;
- task->hdr_max = SKB_TX_PDU_HEADER_LEN;
-
- /* data_out uses scsi_cmd's itt */
- if (opcode != ISCSI_OP_SCSI_DATA_OUT)
- cxgb3i_reserve_itt(task, &task->hdr->itt);
-
- return 0;
-}
-
-int cxgb3i_conn_init_pdu(struct iscsi_task *task, unsigned int offset,
- unsigned int count)
-{
- struct iscsi_conn *conn = task->conn;
- struct iscsi_tcp_task *tcp_task = task->dd_data;
- struct cxgb3i_task_data *tdata = tcp_task->dd_data;
- struct sk_buff *skb = tdata->skb;
- unsigned int datalen = count;
- int i, padlen = iscsi_padding(count);
- struct page *pg;
-
- cxgb3i_tx_debug("task 0x%p,0x%p, offset %u, count %u, skb 0x%p.\n",
- task, task->sc, offset, count, skb);
-
- skb_put(skb, task->hdr_len);
- tx_skb_setmode(skb, conn->hdrdgst_en, datalen ? conn->datadgst_en : 0);
- if (!count)
- return 0;
-
- if (task->sc) {
- struct scsi_data_buffer *sdb = scsi_out(task->sc);
- struct scatterlist *sg = NULL;
- int err;
-
- tdata->offset = offset;
- tdata->count = count;
- err = sgl_seek_offset(sdb->table.sgl, sdb->table.nents,
- tdata->offset, &tdata->sgoffset, &sg);
- if (err < 0) {
- cxgb3i_log_warn("tpdu, sgl %u, bad offset %u/%u.\n",
- sdb->table.nents, tdata->offset,
- sdb->length);
- return err;
- }
- err = sgl_read_to_frags(sg, tdata->sgoffset, tdata->count,
- tdata->frags, MAX_PDU_FRAGS);
- if (err < 0) {
- cxgb3i_log_warn("tpdu, sgl %u, bad offset %u + %u.\n",
- sdb->table.nents, tdata->offset,
- tdata->count);
- return err;
- }
- tdata->nr_frags = err;
-
- if (tdata->nr_frags > MAX_SKB_FRAGS ||
- (padlen && tdata->nr_frags == MAX_SKB_FRAGS)) {
- char *dst = skb->data + task->hdr_len;
- skb_frag_t *frag = tdata->frags;
-
- /* data fits in the skb's headroom */
- for (i = 0; i < tdata->nr_frags; i++, frag++) {
- char *src = kmap_atomic(frag->page,
- KM_SOFTIRQ0);
-
- memcpy(dst, src+frag->page_offset, frag->size);
- dst += frag->size;
- kunmap_atomic(src, KM_SOFTIRQ0);
- }
- if (padlen) {
- memset(dst, 0, padlen);
- padlen = 0;
- }
- skb_put(skb, count + padlen);
- } else {
- /* data fit into frag_list */
- for (i = 0; i < tdata->nr_frags; i++)
- get_page(tdata->frags[i].page);
-
- memcpy(skb_shinfo(skb)->frags, tdata->frags,
- sizeof(skb_frag_t) * tdata->nr_frags);
- skb_shinfo(skb)->nr_frags = tdata->nr_frags;
- skb->len += count;
- skb->data_len += count;
- skb->truesize += count;
- }
-
- } else {
- pg = virt_to_page(task->data);
-
- get_page(pg);
- skb_fill_page_desc(skb, 0, pg, offset_in_page(task->data),
- count);
- skb->len += count;
- skb->data_len += count;
- skb->truesize += count;
- }
-
- if (padlen) {
- i = skb_shinfo(skb)->nr_frags;
- get_page(pad_page);
- skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, pad_page, 0,
- padlen);
-
- skb->data_len += padlen;
- skb->truesize += padlen;
- skb->len += padlen;
- }
-
- return 0;
-}
-
-int cxgb3i_conn_xmit_pdu(struct iscsi_task *task)
-{
- struct iscsi_tcp_conn *tcp_conn = task->conn->dd_data;
- struct cxgb3i_conn *cconn = tcp_conn->dd_data;
- struct iscsi_tcp_task *tcp_task = task->dd_data;
- struct cxgb3i_task_data *tdata = tcp_task->dd_data;
- struct sk_buff *skb = tdata->skb;
- unsigned int datalen;
- int err;
-
- if (!skb)
- return 0;
-
- datalen = skb->data_len;
- tdata->skb = NULL;
- err = cxgb3i_c3cn_send_pdus(cconn->cep->c3cn, skb);
- if (err > 0) {
- int pdulen = err;
-
- cxgb3i_tx_debug("task 0x%p, skb 0x%p, len %u/%u, rv %d.\n",
- task, skb, skb->len, skb->data_len, err);
-
- if (task->conn->hdrdgst_en)
- pdulen += ISCSI_DIGEST_SIZE;
- if (datalen && task->conn->datadgst_en)
- pdulen += ISCSI_DIGEST_SIZE;
-
- task->conn->txdata_octets += pdulen;
- return 0;
- }
-
- if (err == -EAGAIN || err == -ENOBUFS) {
- /* reset skb to send when we are called again */
- tdata->skb = skb;
- return err;
- }
-
- kfree_skb(skb);
- cxgb3i_tx_debug("itt 0x%x, skb 0x%p, len %u/%u, xmit err %d.\n",
- task->itt, skb, skb->len, skb->data_len, err);
- iscsi_conn_printk(KERN_ERR, task->conn, "xmit err %d.\n", err);
- iscsi_conn_failure(task->conn, ISCSI_ERR_XMIT_FAILED);
- return err;
-}
-
-int cxgb3i_pdu_init(void)
-{
- if (SKB_TX_HEADROOM > (512 * MAX_SKB_FRAGS))
- skb_extra_headroom = SKB_TX_HEADROOM;
- pad_page = alloc_page(GFP_KERNEL);
- if (!pad_page)
- return -ENOMEM;
- memset(page_address(pad_page), 0, PAGE_SIZE);
- return 0;
-}
-
-void cxgb3i_pdu_cleanup(void)
-{
- if (pad_page) {
- __free_page(pad_page);
- pad_page = NULL;
- }
-}
-
-void cxgb3i_conn_pdu_ready(struct s3_conn *c3cn)
-{
- struct sk_buff *skb;
- unsigned int read = 0;
- struct iscsi_conn *conn = c3cn->user_data;
- int err = 0;
-
- cxgb3i_rx_debug("cn 0x%p.\n", c3cn);
-
- read_lock(&c3cn->callback_lock);
- if (unlikely(!conn || conn->suspend_rx)) {
- cxgb3i_rx_debug("conn 0x%p, id %d, suspend_rx %lu!\n",
- conn, conn ? conn->id : 0xFF,
- conn ? conn->suspend_rx : 0xFF);
- read_unlock(&c3cn->callback_lock);
- return;
- }
- skb = skb_peek(&c3cn->receive_queue);
- while (!err && skb) {
- __skb_unlink(skb, &c3cn->receive_queue);
- read += skb_rx_pdulen(skb);
- cxgb3i_rx_debug("conn 0x%p, cn 0x%p, rx skb 0x%p, pdulen %u.\n",
- conn, c3cn, skb, skb_rx_pdulen(skb));
- err = cxgb3i_conn_read_pdu_skb(conn, skb);
- __kfree_skb(skb);
- skb = skb_peek(&c3cn->receive_queue);
- }
- read_unlock(&c3cn->callback_lock);
- c3cn->copied_seq += read;
- cxgb3i_c3cn_rx_credits(c3cn, read);
- conn->rxdata_octets += read;
-
- if (err) {
- cxgb3i_log_info("conn 0x%p rx failed err %d.\n", conn, err);
- iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
- }
-}
-
-void cxgb3i_conn_tx_open(struct s3_conn *c3cn)
-{
- struct iscsi_conn *conn = c3cn->user_data;
-
- cxgb3i_tx_debug("cn 0x%p.\n", c3cn);
- if (conn) {
- cxgb3i_tx_debug("cn 0x%p, cid %d.\n", c3cn, conn->id);
- iscsi_conn_queue_work(conn);
- }
-}
-
-void cxgb3i_conn_closing(struct s3_conn *c3cn)
-{
- struct iscsi_conn *conn;
-
- read_lock(&c3cn->callback_lock);
- conn = c3cn->user_data;
- if (conn && c3cn->state != C3CN_STATE_ESTABLISHED)
- iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
- read_unlock(&c3cn->callback_lock);
-}
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