--- /dev/null
+/*
+ * Basic HP/COMPAQ MSA 1000 support. This is only needed if your HW cannot be
+ * upgraded.
+ *
+ * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2006 Mike Christie
+ * Copyright (C) 2008 Hannes Reinecke <hare@suse.de>
+ *
+ * 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; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_dh.h>
+
+#define HP_SW_NAME "hp_sw"
+
+#define HP_SW_TIMEOUT (60 * HZ)
+#define HP_SW_RETRIES 3
+
+#define HP_SW_PATH_UNINITIALIZED -1
+#define HP_SW_PATH_ACTIVE 0
+#define HP_SW_PATH_PASSIVE 1
+
+struct hp_sw_dh_data {
+ struct scsi_dh_data dh_data;
+ unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+ int path_state;
+ int retries;
+ int retry_cnt;
+ struct scsi_device *sdev;
+ activate_complete callback_fn;
+ void *callback_data;
+};
+
+static int hp_sw_start_stop(struct hp_sw_dh_data *);
+
+static inline struct hp_sw_dh_data *get_hp_sw_data(struct scsi_device *sdev)
+{
+ return container_of(sdev->scsi_dh_data, struct hp_sw_dh_data, dh_data);
+}
+
+/*
+ * tur_done - Handle TEST UNIT READY return status
+ * @sdev: sdev the command has been sent to
+ * @errors: blk error code
+ *
+ * Returns SCSI_DH_DEV_OFFLINED if the sdev is on the passive path
+ */
+static int tur_done(struct scsi_device *sdev, unsigned char *sense)
+{
+ struct scsi_sense_hdr sshdr;
+ int ret;
+
+ ret = scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr);
+ if (!ret) {
+ sdev_printk(KERN_WARNING, sdev,
+ "%s: sending tur failed, no sense available\n",
+ HP_SW_NAME);
+ ret = SCSI_DH_IO;
+ goto done;
+ }
+ switch (sshdr.sense_key) {
+ case UNIT_ATTENTION:
+ ret = SCSI_DH_IMM_RETRY;
+ break;
+ case NOT_READY:
+ if ((sshdr.asc == 0x04) && (sshdr.ascq == 2)) {
+ /*
+ * LUN not ready - Initialization command required
+ *
+ * This is the passive path
+ */
+ ret = SCSI_DH_DEV_OFFLINED;
+ break;
+ }
+ /* Fallthrough */
+ default:
+ sdev_printk(KERN_WARNING, sdev,
+ "%s: sending tur failed, sense %x/%x/%x\n",
+ HP_SW_NAME, sshdr.sense_key, sshdr.asc,
+ sshdr.ascq);
+ break;
+ }
+
+done:
+ return ret;
+}
+
+/*
+ * hp_sw_tur - Send TEST UNIT READY
+ * @sdev: sdev command should be sent to
+ *
+ * Use the TEST UNIT READY command to determine
+ * the path state.
+ */
+static int hp_sw_tur(struct scsi_device *sdev, struct hp_sw_dh_data *h)
+{
+ struct request *req;
+ int ret;
+
+retry:
+ req = blk_get_request(sdev->request_queue, WRITE, GFP_NOIO);
+ if (IS_ERR(req))
+ return SCSI_DH_RES_TEMP_UNAVAIL;
+
+ blk_rq_set_block_pc(req);
+ req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+ REQ_FAILFAST_DRIVER;
+ req->cmd_len = COMMAND_SIZE(TEST_UNIT_READY);
+ req->cmd[0] = TEST_UNIT_READY;
+ req->timeout = HP_SW_TIMEOUT;
+ req->sense = h->sense;
+ memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
+ req->sense_len = 0;
+
+ ret = blk_execute_rq(req->q, NULL, req, 1);
+ if (ret == -EIO) {
+ if (req->sense_len > 0) {
+ ret = tur_done(sdev, h->sense);
+ } else {
+ sdev_printk(KERN_WARNING, sdev,
+ "%s: sending tur failed with %x\n",
+ HP_SW_NAME, req->errors);
+ ret = SCSI_DH_IO;
+ }
+ } else {
+ h->path_state = HP_SW_PATH_ACTIVE;
+ ret = SCSI_DH_OK;
+ }
+ if (ret == SCSI_DH_IMM_RETRY) {
+ blk_put_request(req);
+ goto retry;
+ }
+ if (ret == SCSI_DH_DEV_OFFLINED) {
+ h->path_state = HP_SW_PATH_PASSIVE;
+ ret = SCSI_DH_OK;
+ }
+
+ blk_put_request(req);
+
+ return ret;
+}
+
+/*
+ * start_done - Handle START STOP UNIT return status
+ * @sdev: sdev the command has been sent to
+ * @errors: blk error code
+ */
+static int start_done(struct scsi_device *sdev, unsigned char *sense)
+{
+ struct scsi_sense_hdr sshdr;
+ int rc;
+
+ rc = scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr);
+ if (!rc) {
+ sdev_printk(KERN_WARNING, sdev,
+ "%s: sending start_stop_unit failed, "
+ "no sense available\n",
+ HP_SW_NAME);
+ return SCSI_DH_IO;
+ }
+ switch (sshdr.sense_key) {
+ case NOT_READY:
+ if ((sshdr.asc == 0x04) && (sshdr.ascq == 3)) {
+ /*
+ * LUN not ready - manual intervention required
+ *
+ * Switch-over in progress, retry.
+ */
+ rc = SCSI_DH_RETRY;
+ break;
+ }
+ /* fall through */
+ default:
+ sdev_printk(KERN_WARNING, sdev,
+ "%s: sending start_stop_unit failed, sense %x/%x/%x\n",
+ HP_SW_NAME, sshdr.sense_key, sshdr.asc,
+ sshdr.ascq);
+ rc = SCSI_DH_IO;
+ }
+
+ return rc;
+}
+
+static void start_stop_endio(struct request *req, int error)
+{
+ struct hp_sw_dh_data *h = req->end_io_data;
+ unsigned err = SCSI_DH_OK;
+
+ if (error || host_byte(req->errors) != DID_OK ||
+ msg_byte(req->errors) != COMMAND_COMPLETE) {
+ sdev_printk(KERN_WARNING, h->sdev,
+ "%s: sending start_stop_unit failed with %x\n",
+ HP_SW_NAME, req->errors);
+ err = SCSI_DH_IO;
+ goto done;
+ }
+
+ if (req->sense_len > 0) {
+ err = start_done(h->sdev, h->sense);
+ if (err == SCSI_DH_RETRY) {
+ err = SCSI_DH_IO;
+ if (--h->retry_cnt) {
+ blk_put_request(req);
+ err = hp_sw_start_stop(h);
+ if (err == SCSI_DH_OK)
+ return;
+ }
+ }
+ }
+done:
+ req->end_io_data = NULL;
+ __blk_put_request(req->q, req);
+ if (h->callback_fn) {
+ h->callback_fn(h->callback_data, err);
+ h->callback_fn = h->callback_data = NULL;
+ }
+ return;
+
+}
+
+/*
+ * hp_sw_start_stop - Send START STOP UNIT command
+ * @sdev: sdev command should be sent to
+ *
+ * Sending START STOP UNIT activates the SP.
+ */
+static int hp_sw_start_stop(struct hp_sw_dh_data *h)
+{
+ struct request *req;
+
+ req = blk_get_request(h->sdev->request_queue, WRITE, GFP_ATOMIC);
+ if (IS_ERR(req))
+ return SCSI_DH_RES_TEMP_UNAVAIL;
+
+ blk_rq_set_block_pc(req);
+ req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+ REQ_FAILFAST_DRIVER;
+ req->cmd_len = COMMAND_SIZE(START_STOP);
+ req->cmd[0] = START_STOP;
+ req->cmd[4] = 1; /* Start spin cycle */
+ req->timeout = HP_SW_TIMEOUT;
+ req->sense = h->sense;
+ memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
+ req->sense_len = 0;
+ req->end_io_data = h;
+
+ blk_execute_rq_nowait(req->q, NULL, req, 1, start_stop_endio);
+ return SCSI_DH_OK;
+}
+
+static int hp_sw_prep_fn(struct scsi_device *sdev, struct request *req)
+{
+ struct hp_sw_dh_data *h = get_hp_sw_data(sdev);
+ int ret = BLKPREP_OK;
+
+ if (h->path_state != HP_SW_PATH_ACTIVE) {
+ ret = BLKPREP_KILL;
+ req->cmd_flags |= REQ_QUIET;
+ }
+ return ret;
+
+}
+
+/*
+ * hp_sw_activate - Activate a path
+ * @sdev: sdev on the path to be activated
+ *
+ * The HP Active/Passive firmware is pretty simple;
+ * the passive path reports NOT READY with sense codes
+ * 0x04/0x02; a START STOP UNIT command will then
+ * activate the passive path (and deactivate the
+ * previously active one).
+ */
+static int hp_sw_activate(struct scsi_device *sdev,
+ activate_complete fn, void *data)
+{
+ int ret = SCSI_DH_OK;
+ struct hp_sw_dh_data *h = get_hp_sw_data(sdev);
+
+ ret = hp_sw_tur(sdev, h);
+
+ if (ret == SCSI_DH_OK && h->path_state == HP_SW_PATH_PASSIVE) {
+ h->retry_cnt = h->retries;
+ h->callback_fn = fn;
+ h->callback_data = data;
+ ret = hp_sw_start_stop(h);
+ if (ret == SCSI_DH_OK)
+ return 0;
+ h->callback_fn = h->callback_data = NULL;
+ }
+
+ if (fn)
+ fn(data, ret);
+ return 0;
+}
+
+static const struct {
+ char *vendor;
+ char *model;
+} hp_sw_dh_data_list[] = {
+ {"COMPAQ", "MSA1000 VOLUME"},
+ {"COMPAQ", "HSV110"},
+ {"HP", "HSV100"},
+ {"DEC", "HSG80"},
+ {NULL, NULL},
+};
+
+static bool hp_sw_match(struct scsi_device *sdev)
+{
+ int i;
+
+ if (scsi_device_tpgs(sdev))
+ return false;
+
+ for (i = 0; hp_sw_dh_data_list[i].vendor; i++) {
+ if (!strncmp(sdev->vendor, hp_sw_dh_data_list[i].vendor,
+ strlen(hp_sw_dh_data_list[i].vendor)) &&
+ !strncmp(sdev->model, hp_sw_dh_data_list[i].model,
+ strlen(hp_sw_dh_data_list[i].model))) {
+ return true;
+ }
+ }
+ return false;
+}
+
+static struct scsi_dh_data *hp_sw_bus_attach(struct scsi_device *sdev)
+{
+ struct hp_sw_dh_data *h;
+ int ret;
+
+ h = kzalloc(sizeof(*h), GFP_KERNEL);
+ if (!h)
+ return ERR_PTR(-ENOMEM);
+ h->path_state = HP_SW_PATH_UNINITIALIZED;
+ h->retries = HP_SW_RETRIES;
+ h->sdev = sdev;
+
+ ret = hp_sw_tur(sdev, h);
+ if (ret != SCSI_DH_OK || h->path_state == HP_SW_PATH_UNINITIALIZED)
+ goto failed;
+
+ sdev_printk(KERN_INFO, sdev, "%s: attached to %s path\n",
+ HP_SW_NAME, h->path_state == HP_SW_PATH_ACTIVE?
+ "active":"passive");
+ return &h->dh_data;
+failed:
+ kfree(h);
+ return ERR_PTR(-EINVAL);
+}
+
+static void hp_sw_bus_detach( struct scsi_device *sdev )
+{
+ struct hp_sw_dh_data *h = get_hp_sw_data(sdev);
+
+ kfree(h);
+}
+
+static struct scsi_device_handler hp_sw_dh = {
+ .name = HP_SW_NAME,
+ .module = THIS_MODULE,
+ .attach = hp_sw_bus_attach,
+ .detach = hp_sw_bus_detach,
+ .activate = hp_sw_activate,
+ .prep_fn = hp_sw_prep_fn,
+ .match = hp_sw_match,
+};
+
+static int __init hp_sw_init(void)
+{
+ return scsi_register_device_handler(&hp_sw_dh);
+}
+
+static void __exit hp_sw_exit(void)
+{
+ scsi_unregister_device_handler(&hp_sw_dh);
+}
+
+module_init(hp_sw_init);
+module_exit(hp_sw_exit);
+
+MODULE_DESCRIPTION("HP Active/Passive driver");
+MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff