1 files changed, 530 insertions, 0 deletions

diff --git a/src/drivers/block/srp.c b/src/drivers/block/srp.c
new file mode 100644
index 000000000..f50f194ba
--- /dev/null
+++ b/src/drivers/block/srp.c
@@ -0,0 +1,530 @@
+/*
+ * Copyright (C) 2009 Fen Systems Ltd <mbrown@fensystems.co.uk>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in
+ *   the documentation and/or other materials provided with the
+ *   distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+FILE_LICENCE ( BSD2 );
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <gpxe/scsi.h>
+#include <gpxe/xfer.h>
+#include <gpxe/features.h>
+#include <gpxe/ib_srp.h>
+#include <gpxe/srp.h>
+
+/**
+ * @file
+ *
+ * SCSI RDMA Protocol
+ *
+ */
+
+FEATURE ( FEATURE_PROTOCOL, "SRP", DHCP_EB_FEATURE_SRP, 1 );
+
+/** Tag to be used for next SRP IU */
+static unsigned int srp_tag = 0;
+
+static void srp_login ( struct srp_device *srp );
+static void srp_cmd ( struct srp_device *srp );
+
+/**
+ * Mark SRP SCSI command as complete
+ *
+ * @v srp		SRP device
+ * @v rc		Status code
+ */
+static void srp_scsi_done ( struct srp_device *srp, int rc ) {
+	if ( srp->command )
+		srp->command->rc = rc;
+	srp->command = NULL;
+}
+
+/**
+ * Handle SRP session failure
+ *
+ * @v srp		SRP device
+ * @v rc 		Reason for failure
+ */
+static void srp_fail ( struct srp_device *srp, int rc ) {
+
+	/* Close underlying socket */
+	xfer_close ( &srp->socket, rc );
+
+	/* Clear session state */
+	srp->state = 0;
+
+	/* Increment retry count */
+	srp->retry_count++;
+
+	/* If we have reached the retry limit, permanently abort the
+	 * session.
+	 */
+	if ( srp->retry_count >= SRP_MAX_RETRIES ) {
+		srp->instant_rc = rc;
+		srp_scsi_done ( srp, rc );
+		return;
+	}
+
+	/* Otherwise, try to reopen the connection */
+	srp_login ( srp );
+}
+
+/**
+ * Initiate SRP login
+ *
+ * @v srp		SRP device
+ */
+static void srp_login ( struct srp_device *srp ) {
+	struct io_buffer *iobuf;
+	struct srp_login_req *login_req;
+	int rc;
+
+	assert ( ! ( srp->state & SRP_STATE_SOCKET_OPEN ) );
+
+	/* Open underlying socket */
+	if ( ( rc = srp->transport->connect ( srp ) ) != 0 ) {
+		DBGC ( srp, "SRP %p could not open socket: %s\n",
+		       srp, strerror ( rc ) );
+		goto err;
+	}
+	srp->state |= SRP_STATE_SOCKET_OPEN;
+
+	/* Allocate I/O buffer */
+	iobuf = xfer_alloc_iob ( &srp->socket, sizeof ( *login_req ) );
+	if ( ! iobuf ) {
+		rc = -ENOMEM;
+		goto err;
+	}
+
+	/* Construct login request IU */
+	login_req = iob_put ( iobuf, sizeof ( *login_req ) );
+	memset ( login_req, 0, sizeof ( *login_req ) );
+	login_req->type = SRP_LOGIN_REQ;
+	login_req->tag.dwords[1] = htonl ( ++srp_tag );
+	login_req->max_i_t_iu_len = htonl ( SRP_MAX_I_T_IU_LEN );
+	login_req->required_buffer_formats = SRP_LOGIN_REQ_FMT_DDBD;
+	memcpy ( &login_req->port_ids, &srp->port_ids,
+		 sizeof ( login_req->port_ids ) );
+
+	DBGC2 ( srp, "SRP %p TX login request tag %08x%08x\n",
+		srp, ntohl ( login_req->tag.dwords[0] ),
+		ntohl ( login_req->tag.dwords[1] ) );
+	DBGC2_HDA ( srp, 0, iobuf->data, iob_len ( iobuf ) );
+
+	/* Send login request IU */
+	if ( ( rc = xfer_deliver_iob ( &srp->socket, iobuf ) ) != 0 ) {
+		DBGC ( srp, "SRP %p could not send login request: %s\n",
+		       srp, strerror ( rc ) );
+		goto err;
+	}
+
+	return;
+
+ err:
+	srp_fail ( srp, rc );
+}
+
+/**
+ * Handle SRP login response
+ *
+ * @v srp		SRP device
+ * @v iobuf		I/O buffer
+ * @ret rc		Return status code
+ */
+static int srp_login_rsp ( struct srp_device *srp, struct io_buffer *iobuf ) {
+	struct srp_login_rsp *login_rsp = iobuf->data;
+	int rc;
+
+	DBGC2 ( srp, "SRP %p RX login response tag %08x%08x\n",
+		srp, ntohl ( login_rsp->tag.dwords[0] ),
+		ntohl ( login_rsp->tag.dwords[1] ) );
+
+	/* Sanity check */
+	if ( iob_len ( iobuf ) < sizeof ( *login_rsp ) ) {
+		DBGC ( srp, "SRP %p RX login response too short (%zd bytes)\n",
+		       srp, iob_len ( iobuf ) );
+		rc = -EINVAL;
+		goto out;
+	}
+
+	DBGC ( srp, "SRP %p logged in\n", srp );
+
+	/* Mark as logged in */
+	srp->state |= SRP_STATE_LOGGED_IN;
+
+	/* Reset error counter */
+	srp->retry_count = 0;
+
+	/* Issue pending command */
+	srp_cmd ( srp );
+
+	rc = 0;
+ out:
+	free_iob ( iobuf );
+	return rc;
+}
+
+/**
+ * Handle SRP login rejection
+ *
+ * @v srp		SRP device
+ * @v iobuf		I/O buffer
+ * @ret rc		Return status code
+ */
+static int srp_login_rej ( struct srp_device *srp, struct io_buffer *iobuf ) {
+	struct srp_login_rej *login_rej = iobuf->data;
+	int rc;
+
+	DBGC2 ( srp, "SRP %p RX login rejection tag %08x%08x\n",
+		srp, ntohl ( login_rej->tag.dwords[0] ),
+		ntohl ( login_rej->tag.dwords[1] ) );
+
+	/* Sanity check */
+	if ( iob_len ( iobuf ) < sizeof ( *login_rej ) ) {
+		DBGC ( srp, "SRP %p RX login rejection too short (%zd "
+		       "bytes)\n", srp, iob_len ( iobuf ) );
+		rc = -EINVAL;
+		goto out;
+	}
+
+	/* Login rejection always indicates an error */
+	DBGC ( srp, "SRP %p login rejected (reason %08x)\n",
+	       srp, ntohl ( login_rej->reason ) );
+	rc = -EPERM;
+
+ out:
+	free_iob ( iobuf );
+	return rc;
+}
+
+/**
+ * Transmit SRP SCSI command
+ *
+ * @v srp		SRP device
+ */
+static void srp_cmd ( struct srp_device *srp ) {
+	struct io_buffer *iobuf;
+	struct srp_cmd *cmd;
+	struct srp_memory_descriptor *data_out;
+	struct srp_memory_descriptor *data_in;
+	int rc;
+
+	assert ( srp->state & SRP_STATE_LOGGED_IN );
+
+	/* Allocate I/O buffer */
+	iobuf = xfer_alloc_iob ( &srp->socket, SRP_MAX_I_T_IU_LEN );
+	if ( ! iobuf ) {
+		rc = -ENOMEM;
+		goto err;
+	}
+
+	/* Construct base portion */
+	cmd = iob_put ( iobuf, sizeof ( *cmd ) );
+	memset ( cmd, 0, sizeof ( *cmd ) );
+	cmd->type = SRP_CMD;
+	cmd->tag.dwords[1] = htonl ( ++srp_tag );
+	cmd->lun = srp->lun;
+	memcpy ( &cmd->cdb, &srp->command->cdb, sizeof ( cmd->cdb ) );
+
+	/* Construct data-out descriptor, if present */
+	if ( srp->command->data_out ) {
+		cmd->data_buffer_formats |= SRP_CMD_DO_FMT_DIRECT;
+		data_out = iob_put ( iobuf, sizeof ( *data_out ) );
+		data_out->address =
+		    cpu_to_be64 ( user_to_phys ( srp->command->data_out, 0 ) );
+		data_out->handle = ntohl ( srp->memory_handle );
+		data_out->len = ntohl ( srp->command->data_out_len );
+	}
+
+	/* Construct data-in descriptor, if present */
+	if ( srp->command->data_in ) {
+		cmd->data_buffer_formats |= SRP_CMD_DI_FMT_DIRECT;
+		data_in = iob_put ( iobuf, sizeof ( *data_in ) );
+		data_in->address =
+		     cpu_to_be64 ( user_to_phys ( srp->command->data_in, 0 ) );
+		data_in->handle = ntohl ( srp->memory_handle );
+		data_in->len = ntohl ( srp->command->data_in_len );
+	}
+
+	DBGC2 ( srp, "SRP %p TX SCSI command tag %08x%08x\n", srp,
+		ntohl ( cmd->tag.dwords[0] ), ntohl ( cmd->tag.dwords[1] ) );
+	DBGC2_HDA ( srp, 0, iobuf->data, iob_len ( iobuf ) );
+
+	/* Send IU */
+	if ( ( rc = xfer_deliver_iob ( &srp->socket, iobuf ) ) != 0 ) {
+		DBGC ( srp, "SRP %p could not send command: %s\n",
+		       srp, strerror ( rc ) );
+		goto err;
+	}
+
+	return;
+
+ err:
+	srp_fail ( srp, rc );
+}
+
+/**
+ * Handle SRP SCSI response
+ *
+ * @v srp		SRP device
+ * @v iobuf		I/O buffer
+ * @ret rc		Returns status code
+ */
+static int srp_rsp ( struct srp_device *srp, struct io_buffer *iobuf ) {
+	struct srp_rsp *rsp = iobuf->data;
+	int rc;
+
+	DBGC2 ( srp, "SRP %p RX SCSI response tag %08x%08x\n", srp,
+		ntohl ( rsp->tag.dwords[0] ), ntohl ( rsp->tag.dwords[1] ) );
+
+	/* Sanity check */
+	if ( iob_len ( iobuf ) < sizeof ( *rsp ) ) {
+		DBGC ( srp, "SRP %p RX SCSI response too short (%zd bytes)\n",
+		       srp, iob_len ( iobuf ) );
+		rc = -EINVAL;
+		goto out;
+	}
+
+	/* Report SCSI errors */
+	if ( rsp->status != 0 ) {
+		DBGC ( srp, "SRP %p response status %02x\n",
+		       srp, rsp->status );
+		if ( srp_rsp_sense_data ( rsp ) ) {
+			DBGC ( srp, "SRP %p sense data:\n", srp );
+			DBGC_HDA ( srp, 0, srp_rsp_sense_data ( rsp ),
+				   srp_rsp_sense_data_len ( rsp ) );
+		}
+	}
+	if ( rsp->valid & ( SRP_RSP_VALID_DOUNDER | SRP_RSP_VALID_DOOVER ) ) {
+		DBGC ( srp, "SRP %p response data-out %srun by %#x bytes\n",
+		       srp, ( ( rsp->valid & SRP_RSP_VALID_DOUNDER )
+			      ? "under" : "over" ),
+		       ntohl ( rsp->data_out_residual_count ) );
+	}
+	if ( rsp->valid & ( SRP_RSP_VALID_DIUNDER | SRP_RSP_VALID_DIOVER ) ) {
+		DBGC ( srp, "SRP %p response data-in %srun by %#x bytes\n",
+		       srp, ( ( rsp->valid & SRP_RSP_VALID_DIUNDER )
+			      ? "under" : "over" ),
+		       ntohl ( rsp->data_in_residual_count ) );
+	}
+	srp->command->status = rsp->status;
+
+	/* Mark SCSI command as complete */
+	srp_scsi_done ( srp, 0 );
+
+	rc = 0;
+ out:
+	free_iob ( iobuf );
+	return rc;
+}
+
+/**
+ * Handle SRP unrecognised response
+ *
+ * @v srp		SRP device
+ * @v iobuf		I/O buffer
+ * @ret rc		Returns status code
+ */
+static int srp_unrecognised ( struct srp_device *srp,
+			      struct io_buffer *iobuf ) {
+	struct srp_common *common = iobuf->data;
+
+	DBGC ( srp, "SRP %p RX unrecognised IU tag %08x%08x type %02x\n",
+	       srp, ntohl ( common->tag.dwords[0] ),
+	       ntohl ( common->tag.dwords[1] ), common->type );
+
+	free_iob ( iobuf );
+	return -ENOTSUP;
+}
+
+/**
+ * Receive data from underlying socket
+ *
+ * @v xfer		Data transfer interface
+ * @v iobuf		Datagram I/O buffer
+ * @v meta		Data transfer metadata
+ * @ret rc		Return status code
+ */
+static int srp_xfer_deliver_iob ( struct xfer_interface *xfer,
+				  struct io_buffer *iobuf,
+				  struct xfer_metadata *meta __unused ) {
+	struct srp_device *srp =
+		container_of ( xfer, struct srp_device, socket );
+	struct srp_common *common = iobuf->data;
+	int ( * type ) ( struct srp_device *srp, struct io_buffer *iobuf );
+	int rc;
+
+	/* Determine IU type */
+	switch ( common->type ) {
+	case SRP_LOGIN_RSP:
+		type = srp_login_rsp;
+		break;
+	case SRP_LOGIN_REJ:
+		type = srp_login_rej;
+		break;
+	case SRP_RSP:
+		type = srp_rsp;
+		break;
+	default:
+		type = srp_unrecognised;
+		break;
+	}
+
+	/* Handle IU */
+	if ( ( rc = type ( srp, iobuf ) ) != 0 )
+		goto err;
+
+	return 0;
+
+ err:
+	srp_fail ( srp, rc );
+	return rc;
+}
+
+/**
+ * Underlying socket closed
+ *
+ * @v xfer		Data transfer interface
+ * @v rc		Reason for close
+ */
+static void srp_xfer_close ( struct xfer_interface *xfer, int rc ) {
+	struct srp_device *srp =
+		container_of ( xfer, struct srp_device, socket );
+
+	DBGC ( srp, "SRP %p socket closed: %s\n", srp, strerror ( rc ) );
+
+	srp_fail ( srp, rc );
+}
+
+/** SRP data transfer interface operations */
+static struct xfer_interface_operations srp_xfer_operations = {
+	.close		= srp_xfer_close,
+	.vredirect	= ignore_xfer_vredirect,
+	.window		= unlimited_xfer_window,
+	.alloc_iob	= default_xfer_alloc_iob,
+	.deliver_iob	= srp_xfer_deliver_iob,
+	.deliver_raw	= xfer_deliver_as_iob,
+};
+
+/**
+ * Issue SCSI command via SRP
+ *
+ * @v scsi		SCSI device
+ * @v command		SCSI command
+ * @ret rc		Return status code
+ */
+static int srp_command ( struct scsi_device *scsi,
+			 struct scsi_command *command ) {
+	struct srp_device *srp =
+		container_of ( scsi->backend, struct srp_device, refcnt );
+
+	/* Return instant failure, if we have already aborted the session */
+	if ( srp->instant_rc )
+		return srp->instant_rc;
+
+	/* Store SCSI command */
+	if ( srp->command ) {
+		DBGC ( srp, "SRP %p cannot handle concurrent SCSI commands\n",
+		       srp );
+		return -EBUSY;
+	}
+	srp->command = command;
+
+	/* Log in or issue command as appropriate */
+	if ( ! ( srp->state & SRP_STATE_SOCKET_OPEN ) ) {
+		srp_login ( srp );
+	} else if ( srp->state & SRP_STATE_LOGGED_IN ) {
+		srp_cmd ( srp );
+	} else {
+		/* Still waiting for login; do nothing */
+	}
+
+	return 0;
+}
+
+/**
+ * Attach SRP device
+ *
+ * @v scsi		SCSI device
+ * @v root_path		Root path
+ */
+int srp_attach ( struct scsi_device *scsi, const char *root_path ) {
+	struct srp_transport_type *transport;
+	struct srp_device *srp;
+	int rc;
+
+	/* Hard-code an IB SRP back-end for now */
+	transport = &ib_srp_transport;
+
+	/* Allocate and initialise structure */
+	srp = zalloc ( sizeof ( *srp ) + transport->priv_len );
+	if ( ! srp ) {
+		rc = -ENOMEM;
+		goto err_alloc;
+	}
+	xfer_init ( &srp->socket, &srp_xfer_operations, &srp->refcnt );
+	srp->transport = transport;
+	DBGC ( srp, "SRP %p using %s\n", srp, root_path );
+
+	/* Parse root path */
+	if ( ( rc = transport->parse_root_path ( srp, root_path ) ) != 0 ) {
+		DBGC ( srp, "SRP %p could not parse root path: %s\n",
+		       srp, strerror ( rc ) );
+		goto err_parse_root_path;
+	}
+
+	/* Attach parent interface, mortalise self, and return */
+	scsi->backend = ref_get ( &srp->refcnt );
+	scsi->command = srp_command;
+	ref_put ( &srp->refcnt );
+	return 0;
+
+ err_parse_root_path:
+	ref_put ( &srp->refcnt );
+ err_alloc:
+	return rc;
+}
+
+/**
+ * Detach SRP device
+ *
+ * @v scsi		SCSI device
+ */
+void srp_detach ( struct scsi_device *scsi ) {
+	struct srp_device *srp =
+		container_of ( scsi->backend, struct srp_device, refcnt );
+
+	/* Close socket */
+	xfer_nullify ( &srp->socket );
+	xfer_close ( &srp->socket, 0 );
+	scsi->command = scsi_detached_command;
+	ref_put ( scsi->backend );
+	scsi->backend = NULL;
+}