[SCSI] scsi_dh: add EMC Clariion device handler
authorChandra Seetharaman <sekharan@us.ibm.com>
Thu, 1 May 2008 21:50:04 +0000 (14:50 -0700)
committerJames Bottomley <James.Bottomley@HansenPartnership.com>
Thu, 5 Jun 2008 14:23:40 +0000 (09:23 -0500)
This adds support for EMC Clariions. This patch has the features that
currently exists in mainline and advanced features from Ed's patches.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
drivers/scsi/device_handler/Kconfig
drivers/scsi/device_handler/Makefile
drivers/scsi/device_handler/scsi_dh_emc.c [new file with mode: 0644]

index 61578d84fa6e8239774a10215ff2ad0bde260846..2adc0f666b682fbd8e738299a4b385a8505761bc 100644 (file)
@@ -24,3 +24,9 @@ config SCSI_DH_HP_SW
        If you have a HP/COMPAQ MSA device that requires START_STOP to
        be sent to start it and cannot upgrade the firmware then select y.
        Otherwise, say N.
+
+config SCSI_DH_EMC
+       tristate "EMC CLARiiON Device Handler"
+       depends on SCSI_DH
+       help
+       If you have a EMC CLARiiON select y. Otherwise, say N.
index 08ec1943f19ed3fe07092271ccca0d213168eed2..35272e93b1c82578c624a8213c692f221eaa9426 100644 (file)
@@ -4,3 +4,4 @@
 obj-$(CONFIG_SCSI_DH)          += scsi_dh.o
 obj-$(CONFIG_SCSI_DH_RDAC)     += scsi_dh_rdac.o
 obj-$(CONFIG_SCSI_DH_HP_SW)    += scsi_dh_hp_sw.o
+obj-$(CONFIG_SCSI_DH_EMC)      += scsi_dh_emc.o
diff --git a/drivers/scsi/device_handler/scsi_dh_emc.c b/drivers/scsi/device_handler/scsi_dh_emc.c
new file mode 100644 (file)
index 0000000..ed53f14
--- /dev/null
@@ -0,0 +1,499 @@
+/*
+ * Target driver for EMC CLARiiON AX/CX-series hardware.
+ * Based on code from Lars Marowsky-Bree <lmb@suse.de>
+ * and Ed Goggin <egoggin@emc.com>.
+ *
+ * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
+ * Copyright (C) 2006 Mike Christie
+ *
+ * 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 <scsi/scsi.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_dh.h>
+#include <scsi/scsi_device.h>
+
+#define CLARIION_NAME                  "emc_clariion"
+
+#define CLARIION_TRESPASS_PAGE         0x22
+#define CLARIION_BUFFER_SIZE           0x80
+#define CLARIION_TIMEOUT               (60 * HZ)
+#define CLARIION_RETRIES               3
+#define CLARIION_UNBOUND_LU            -1
+
+static unsigned char long_trespass[] = {
+       0, 0, 0, 0,
+       CLARIION_TRESPASS_PAGE, /* Page code */
+       0x09,                   /* Page length - 2 */
+       0x81,                   /* Trespass code + Honor reservation bit */
+       0xff, 0xff,             /* Trespass target */
+       0, 0, 0, 0, 0, 0        /* Reserved bytes / unknown */
+};
+
+static unsigned char long_trespass_hr[] = {
+       0, 0, 0, 0,
+       CLARIION_TRESPASS_PAGE, /* Page code */
+       0x09,                   /* Page length - 2 */
+       0x01,                   /* Trespass code + Honor reservation bit */
+       0xff, 0xff,             /* Trespass target */
+       0, 0, 0, 0, 0, 0        /* Reserved bytes / unknown */
+};
+
+static unsigned char short_trespass[] = {
+       0, 0, 0, 0,
+       CLARIION_TRESPASS_PAGE, /* Page code */
+       0x02,                   /* Page length - 2 */
+       0x81,                   /* Trespass code + Honor reservation bit */
+       0xff,                   /* Trespass target */
+};
+
+static unsigned char short_trespass_hr[] = {
+       0, 0, 0, 0,
+       CLARIION_TRESPASS_PAGE, /* Page code */
+       0x02,                   /* Page length - 2 */
+       0x01,                   /* Trespass code + Honor reservation bit */
+       0xff,                   /* Trespass target */
+};
+
+struct clariion_dh_data {
+       /*
+        * Use short trespass command (FC-series) or the long version
+        * (default for AX/CX CLARiiON arrays).
+        */
+       unsigned short_trespass;
+       /*
+        * Whether or not (default) to honor SCSI reservations when
+        * initiating a switch-over.
+        */
+       unsigned hr;
+       /* I/O buffer for both MODE_SELECT and INQUIRY commands. */
+       char buffer[CLARIION_BUFFER_SIZE];
+       /*
+        * SCSI sense buffer for commands -- assumes serial issuance
+        * and completion sequence of all commands for same multipath.
+        */
+       unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+       /* which SP (A=0,B=1,UNBOUND=-1) is dflt SP for path's mapped dev */
+       int default_sp;
+       /* which SP (A=0,B=1,UNBOUND=-1) is active for path's mapped dev */
+       int current_sp;
+};
+
+static inline struct clariion_dh_data
+                       *get_clariion_data(struct scsi_device *sdev)
+{
+       struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
+       BUG_ON(scsi_dh_data == NULL);
+       return ((struct clariion_dh_data *) scsi_dh_data->buf);
+}
+
+/*
+ * Parse MODE_SELECT cmd reply.
+ */
+static int trespass_endio(struct scsi_device *sdev, int result)
+{
+       int err = SCSI_DH_OK;
+       struct scsi_sense_hdr sshdr;
+       struct clariion_dh_data *csdev = get_clariion_data(sdev);
+       char *sense = csdev->sense;
+
+       if (status_byte(result) == CHECK_CONDITION &&
+           scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)) {
+               sdev_printk(KERN_ERR, sdev, "Found valid sense data 0x%2x, "
+                           "0x%2x, 0x%2x while sending CLARiiON trespass "
+                           "command.\n", sshdr.sense_key, sshdr.asc,
+                            sshdr.ascq);
+
+               if ((sshdr.sense_key == 0x05) && (sshdr.asc == 0x04) &&
+                    (sshdr.ascq == 0x00)) {
+                       /*
+                        * Array based copy in progress -- do not send
+                        * mode_select or copy will be aborted mid-stream.
+                        */
+                       sdev_printk(KERN_INFO, sdev, "Array Based Copy in "
+                                   "progress while sending CLARiiON trespass "
+                                   "command.\n");
+                       err = SCSI_DH_DEV_TEMP_BUSY;
+               } else if ((sshdr.sense_key == 0x02) && (sshdr.asc == 0x04) &&
+                           (sshdr.ascq == 0x03)) {
+                       /*
+                        * LUN Not Ready - Manual Intervention Required
+                        * indicates in-progress ucode upgrade (NDU).
+                        */
+                       sdev_printk(KERN_INFO, sdev, "Detected in-progress "
+                                   "ucode upgrade NDU operation while sending "
+                                   "CLARiiON trespass command.\n");
+                       err = SCSI_DH_DEV_TEMP_BUSY;
+               } else
+                       err = SCSI_DH_DEV_FAILED;
+       } else if (result) {
+               sdev_printk(KERN_ERR, sdev, "Error 0x%x while sending "
+                           "CLARiiON trespass command.\n", result);
+               err = SCSI_DH_IO;
+       }
+
+       return err;
+}
+
+static int parse_sp_info_reply(struct scsi_device *sdev, int result,
+               int *default_sp, int *current_sp, int *new_current_sp)
+{
+       int err = SCSI_DH_OK;
+       struct clariion_dh_data *csdev = get_clariion_data(sdev);
+
+       if (result == 0) {
+               /* check for in-progress ucode upgrade (NDU) */
+               if (csdev->buffer[48] != 0) {
+                       sdev_printk(KERN_NOTICE, sdev, "Detected in-progress "
+                              "ucode upgrade NDU operation while finding "
+                              "current active SP.");
+                       err = SCSI_DH_DEV_TEMP_BUSY;
+               } else {
+                       *default_sp = csdev->buffer[5];
+
+                       if (csdev->buffer[4] == 2)
+                               /* SP for path is current */
+                               *current_sp = csdev->buffer[8];
+                       else {
+                               if (csdev->buffer[4] == 1)
+                                       /* SP for this path is NOT current */
+                                       if (csdev->buffer[8] == 0)
+                                               *current_sp = 1;
+                                       else
+                                               *current_sp = 0;
+                               else
+                                       /* unbound LU or LUNZ */
+                                       *current_sp = CLARIION_UNBOUND_LU;
+                       }
+                       *new_current_sp =  csdev->buffer[8];
+               }
+       } else {
+               struct scsi_sense_hdr sshdr;
+
+               err = SCSI_DH_IO;
+
+               if (scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
+                                                          &sshdr))
+                       sdev_printk(KERN_ERR, sdev, "Found valid sense data "
+                             "0x%2x, 0x%2x, 0x%2x while finding current "
+                             "active SP.", sshdr.sense_key, sshdr.asc,
+                             sshdr.ascq);
+               else
+                       sdev_printk(KERN_ERR, sdev, "Error 0x%x finding "
+                             "current active SP.", result);
+       }
+
+       return err;
+}
+
+static int sp_info_endio(struct scsi_device *sdev, int result,
+                                       int mode_select_sent, int *done)
+{
+       struct clariion_dh_data *csdev = get_clariion_data(sdev);
+       int err_flags, default_sp, current_sp, new_current_sp;
+
+       err_flags = parse_sp_info_reply(sdev, result, &default_sp,
+                                            &current_sp, &new_current_sp);
+
+       if (err_flags != SCSI_DH_OK)
+               goto done;
+
+       if (mode_select_sent) {
+               csdev->default_sp = default_sp;
+               csdev->current_sp = current_sp;
+       } else {
+               /*
+                * Issue the actual module_selec request IFF either
+                * (1) we do not know the identity of the current SP OR
+                * (2) what we think we know is actually correct.
+                */
+               if ((current_sp != CLARIION_UNBOUND_LU) &&
+                   (new_current_sp != current_sp)) {
+
+                       csdev->default_sp = default_sp;
+                       csdev->current_sp = current_sp;
+
+                       sdev_printk(KERN_INFO, sdev, "Ignoring path group "
+                              "switch-over command for CLARiiON SP%s since "
+                              " mapped device is already initialized.",
+                              current_sp ? "B" : "A");
+                       if (done)
+                               *done = 1; /* as good as doing it */
+               }
+       }
+done:
+       return err_flags;
+}
+
+/*
+* Get block request for REQ_BLOCK_PC command issued to path.  Currently
+* limited to MODE_SELECT (trespass) and INQUIRY (VPD page 0xC0) commands.
+*
+* Uses data and sense buffers in hardware handler context structure and
+* assumes serial servicing of commands, both issuance and completion.
+*/
+static struct request *get_req(struct scsi_device *sdev, int cmd)
+{
+       struct clariion_dh_data *csdev = get_clariion_data(sdev);
+       struct request *rq;
+       unsigned char *page22;
+       int len = 0;
+
+       rq = blk_get_request(sdev->request_queue,
+                       (cmd == MODE_SELECT) ? WRITE : READ, GFP_ATOMIC);
+       if (!rq) {
+               sdev_printk(KERN_INFO, sdev, "get_req: blk_get_request failed");
+               return NULL;
+       }
+
+       memset(&rq->cmd, 0, BLK_MAX_CDB);
+       rq->cmd[0] = cmd;
+       rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
+
+       switch (cmd) {
+       case MODE_SELECT:
+               if (csdev->short_trespass) {
+                       page22 = csdev->hr ? short_trespass_hr : short_trespass;
+                       len = sizeof(short_trespass);
+               } else {
+                       page22 = csdev->hr ? long_trespass_hr : long_trespass;
+                       len = sizeof(long_trespass);
+               }
+               /*
+                * Can't DMA from kernel BSS -- must copy selected trespass
+                * command mode page contents to context buffer which is
+                * allocated by kmalloc.
+                */
+               BUG_ON((len > CLARIION_BUFFER_SIZE));
+               memcpy(csdev->buffer, page22, len);
+               rq->cmd_flags |= REQ_RW;
+               rq->cmd[1] = 0x10;
+               break;
+       case INQUIRY:
+               rq->cmd[1] = 0x1;
+               rq->cmd[2] = 0xC0;
+               len = CLARIION_BUFFER_SIZE;
+               memset(csdev->buffer, 0, CLARIION_BUFFER_SIZE);
+               break;
+       default:
+               BUG_ON(1);
+               break;
+       }
+
+       rq->cmd[4] = len;
+       rq->cmd_type = REQ_TYPE_BLOCK_PC;
+       rq->cmd_flags |= REQ_FAILFAST;
+       rq->timeout = CLARIION_TIMEOUT;
+       rq->retries = CLARIION_RETRIES;
+
+       rq->sense = csdev->sense;
+       memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
+       rq->sense_len = 0;
+
+       if (blk_rq_map_kern(sdev->request_queue, rq, csdev->buffer,
+                                                       len, GFP_ATOMIC)) {
+               __blk_put_request(rq->q, rq);
+               return NULL;
+       }
+
+       return rq;
+}
+
+static int send_cmd(struct scsi_device *sdev, int cmd)
+{
+       struct request *rq = get_req(sdev, cmd);
+
+       if (!rq)
+               return SCSI_DH_RES_TEMP_UNAVAIL;
+
+       return blk_execute_rq(sdev->request_queue, NULL, rq, 1);
+}
+
+static int clariion_activate(struct scsi_device *sdev)
+{
+       int result, done = 0;
+
+       result = send_cmd(sdev, INQUIRY);
+       result = sp_info_endio(sdev, result, 0, &done);
+       if (result || done)
+               goto done;
+
+       result = send_cmd(sdev, MODE_SELECT);
+       result = trespass_endio(sdev, result);
+       if (result)
+               goto done;
+
+       result = send_cmd(sdev, INQUIRY);
+       result = sp_info_endio(sdev, result, 1, NULL);
+done:
+       return result;
+}
+
+static int clariion_check_sense(struct scsi_device *sdev,
+                               struct scsi_sense_hdr *sense_hdr)
+{
+       switch (sense_hdr->sense_key) {
+       case NOT_READY:
+               if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x03)
+                       /*
+                        * LUN Not Ready - Manual Intervention Required
+                        * indicates this is a passive path.
+                        *
+                        * FIXME: However, if this is seen and EVPD C0
+                        * indicates that this is due to a NDU in
+                        * progress, we should set FAIL_PATH too.
+                        * This indicates we might have to do a SCSI
+                        * inquiry in the end_io path. Ugh.
+                        *
+                        * Can return FAILED only when we want the error
+                        * recovery process to kick in.
+                        */
+                       return SUCCESS;
+               break;
+       case ILLEGAL_REQUEST:
+               if (sense_hdr->asc == 0x25 && sense_hdr->ascq == 0x01)
+                       /*
+                        * An array based copy is in progress. Do not
+                        * fail the path, do not bypass to another PG,
+                        * do not retry. Fail the IO immediately.
+                        * (Actually this is the same conclusion as in
+                        * the default handler, but lets make sure.)
+                        *
+                        * Can return FAILED only when we want the error
+                        * recovery process to kick in.
+                        */
+                       return SUCCESS;
+               break;
+       case UNIT_ATTENTION:
+               if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
+                       /*
+                        * Unit Attention Code. This is the first IO
+                        * to the new path, so just retry.
+                        */
+                       return NEEDS_RETRY;
+               break;
+       }
+
+       /* success just means we do not care what scsi-ml does */
+       return SUCCESS;
+}
+
+static const struct {
+       char *vendor;
+       char *model;
+} clariion_dev_list[] = {
+       {"DGC", "RAID"},
+       {"DGC", "DISK"},
+       {NULL, NULL},
+};
+
+static int clariion_bus_notify(struct notifier_block *, unsigned long, void *);
+
+static struct scsi_device_handler clariion_dh = {
+       .name           = CLARIION_NAME,
+       .module         = THIS_MODULE,
+       .nb.notifier_call = clariion_bus_notify,
+       .check_sense    = clariion_check_sense,
+       .activate       = clariion_activate,
+};
+
+/*
+ * TODO: need some interface so we can set trespass values
+ */
+static int clariion_bus_notify(struct notifier_block *nb,
+                               unsigned long action, void *data)
+{
+       struct device *dev = data;
+       struct scsi_device *sdev = to_scsi_device(dev);
+       struct scsi_dh_data *scsi_dh_data;
+       struct clariion_dh_data *h;
+       int i, found = 0;
+       unsigned long flags;
+
+       if (action == BUS_NOTIFY_ADD_DEVICE) {
+               for (i = 0; clariion_dev_list[i].vendor; i++) {
+                       if (!strncmp(sdev->vendor, clariion_dev_list[i].vendor,
+                                    strlen(clariion_dev_list[i].vendor)) &&
+                           !strncmp(sdev->model, clariion_dev_list[i].model,
+                                    strlen(clariion_dev_list[i].model))) {
+                               found = 1;
+                               break;
+                       }
+               }
+               if (!found)
+                       goto out;
+
+               scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
+                               + sizeof(*h) , GFP_KERNEL);
+               if (!scsi_dh_data) {
+                       sdev_printk(KERN_ERR, sdev, "Attach failed %s.\n",
+                                   CLARIION_NAME);
+                       goto out;
+               }
+
+               scsi_dh_data->scsi_dh = &clariion_dh;
+               h = (struct clariion_dh_data *) scsi_dh_data->buf;
+               h->default_sp = CLARIION_UNBOUND_LU;
+               h->current_sp = CLARIION_UNBOUND_LU;
+
+               spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+               sdev->scsi_dh_data = scsi_dh_data;
+               spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+
+               sdev_printk(KERN_NOTICE, sdev, "Attached %s.\n", CLARIION_NAME);
+               try_module_get(THIS_MODULE);
+
+       } else if (action == BUS_NOTIFY_DEL_DEVICE) {
+               if (sdev->scsi_dh_data == NULL ||
+                               sdev->scsi_dh_data->scsi_dh != &clariion_dh)
+                       goto out;
+
+               spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+               scsi_dh_data = sdev->scsi_dh_data;
+               sdev->scsi_dh_data = NULL;
+               spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+
+               sdev_printk(KERN_NOTICE, sdev, "Dettached %s.\n",
+                           CLARIION_NAME);
+
+               kfree(scsi_dh_data);
+               module_put(THIS_MODULE);
+       }
+
+out:
+       return 0;
+}
+
+static int __init clariion_init(void)
+{
+       int r;
+
+       r = scsi_register_device_handler(&clariion_dh);
+       if (r != 0)
+               printk(KERN_ERR "Failed to register scsi device handler.");
+       return r;
+}
+
+static void __exit clariion_exit(void)
+{
+       scsi_unregister_device_handler(&clariion_dh);
+}
+
+module_init(clariion_init);
+module_exit(clariion_exit);
+
+MODULE_DESCRIPTION("EMC CX/AX/FC-family driver");
+MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, Chandra Seetharaman <sekharan@us.ibm.com>");
+MODULE_LICENSE("GPL");