Re: [PATCH 9/9] scsi_dh: Add NetApp hardware handler

[Martin George <marting@netapp.com>]

Yes Chandra, that code needs to be added. Will look into it.

Thanks,
-Martin


Chandra Seetharaman wrote:
>
> One question: If a lun goes to the passive state, how does it get back
> to active ? There is no code to set the state back.
>
> On Tue, 2008-06-24 at 12:05 +0200, Hannes Reinecke wrote:
> > NetApp specific hardware handler to filter out vendor-specific
> > sense code.
> >
> > Signed-off-by: Martin George <marting@netapp.com>
> > Signed-off-by: Hannes Reinecke <hare@suse.de>
> > ---
> >  drivers/scsi/device_handler/Kconfig         |    6 +
> >  drivers/scsi/device_handler/Makefile        |    1 +
> >  drivers/scsi/device_handler/scsi_dh_ontap.c |  157 
> +++++++++++++++++++++++++++
> >  3 files changed, 164 insertions(+), 0 deletions(-)
> >  create mode 100644 drivers/scsi/device_handler/scsi_dh_ontap.c
> >
> > diff --git a/drivers/scsi/device_handler/Kconfig 
> b/drivers/scsi/device_handler/Kconfig
> > index 6707025..841e0e4 100644
> > --- a/drivers/scsi/device_handler/Kconfig
> > +++ b/drivers/scsi/device_handler/Kconfig
> > @@ -31,6 +31,12 @@ config SCSI_DH_EMC
> >       help
> >       If you have a EMC CLARiiON select y. Otherwise, say N.
> >
> > +config SCSI_DH_ONTAP
> > +     tristate "NetApp Device Handler"
> > +     depends on SCSI_DH
> > +     help
> > +     If you have a NetApp controller select y. Otherwise, say N.
> > +
> >  config SCSI_DH_ALUA
> >       tristate "SPC-3 ALUA Device Handler (EXPERIMENTAL)"
> >       depends on SCSI_DH && EXPERIMENTAL
> > diff --git a/drivers/scsi/device_handler/Makefile 
> b/drivers/scsi/device_handler/Makefile
> > index e1d2ea0..abfb9db 100644
> > --- a/drivers/scsi/device_handler/Makefile
> > +++ b/drivers/scsi/device_handler/Makefile
> > @@ -5,4 +5,5 @@ 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
> > +obj-$(CONFIG_SCSI_DH_ONTAP)  += scsi_dh_ontap.o
> >  obj-$(CONFIG_SCSI_DH_ALUA)   += scsi_dh_alua.o
> > diff --git a/drivers/scsi/device_handler/scsi_dh_ontap.c 
> b/drivers/scsi/device_handler/scsi_dh_ontap.c
> > new file mode 100644
> > index 0000000..175d657
> > --- /dev/null
> > +++ b/drivers/scsi/device_handler/scsi_dh_ontap.c
> > @@ -0,0 +1,157 @@
> > +/*
> > + * Copyright 2008 NetApp, Inc., All Rights Reserved
> > + * Author:  Martin George available at marting@netapp.com
> > + *
> > + * This file is released under the GPL.
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 as
> > + * published by the Free Software Foundation.
> > + *
> > + * 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 v2 for more details.
> > + */
> > +
> > +#include <scsi/scsi.h>
> > +#include <scsi/scsi_eh.h>
> > +#include <scsi/scsi_dh.h>
> > +
> > +#define ONTAP_NAME                   "ontap"
> > +
> > +#define ONTAP_STATE_ACTIVE           0
> > +#define ONTAP_STATE_PASSIVE          1
> > +
> > +struct ontap_dh_data {
> > +     /* To add more members here later */
> > +     unsigned char                   state;
> > +};
> > +
> > +static inline struct ontap_dh_data *get_ontap_data(struct 
> scsi_device *sdev)
> > +{
> > +     struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
> > +
> > +     BUG_ON(scsi_dh_data == NULL);
> > +     return ((struct ontap_dh_data *) scsi_dh_data->buf);
> > +}
> > +
> > +static int ontap_prep_fn(struct scsi_device *sdev, struct request *req)
> > +{
> > +     struct ontap_dh_data *h = get_ontap_data(sdev);
> > +     int ret = BLKPREP_OK;
> > +
> > +     if (h->state != ONTAP_STATE_ACTIVE) {
> > +             ret = BLKPREP_KILL;
> > +             req->cmd_flags |= REQ_QUIET;
> > +     }
> > +     return ret;
> > +}
> > +
> > +static int ontap_check_sense(struct scsi_device *sdev,
> > +                             struct scsi_sense_hdr *sense_hdr)
> > +{
> > +     struct ontap_dh_data *h = get_ontap_data(sdev);
> > +
> > +     switch (sense_hdr->sense_key) {
> > +     case HARDWARE_ERROR:
> > +             if (sense_hdr->asc == 0x5D && sense_hdr->ascq == 0x12) {
> > +                     /* Failed write on NetApp controller
> > +                         * Fail the IO */
> > +                     h->state = ONTAP_STATE_PASSIVE;
> > +                     return FAILED;
> > +             }
> > +             break;
> > +     }
> > +
> > +     /* Do not care what scsi-ml does */
> > +     return SCSI_RETURN_NOT_HANDLED;
> > +}
> > +
> > +const struct scsi_dh_devlist ontap_dev_list[] = {
> > +     {"NETAPP", "LUN"},
> > +     {NULL, NULL},
> > +};
> > +
> > +static int ontap_bus_attach(struct scsi_device *sdev);
> > +static void ontap_bus_detach(struct scsi_device *sdev);
> > +
> > +static struct scsi_device_handler ontap_dh = {
> > +     .name           = ONTAP_NAME,
> > +     .module         = THIS_MODULE,
> > +     .devlist        = ontap_dev_list,
> > +     .attach         = ontap_bus_attach,
> > +     .detach         = ontap_bus_detach,
> > +     .check_sense    = ontap_check_sense,
> > +     .prep_fn        = ontap_prep_fn,
> > +};
> > +
> > +static int ontap_bus_attach(struct scsi_device *sdev)
> > +{
> > +     struct scsi_dh_data *scsi_dh_data;
> > +     struct ontap_dh_data *h;
> > +     unsigned long flags;
> > +     int i, found = 0;
> > +
> > +     scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
> > +                            + sizeof(*h) , GFP_KERNEL);
> > +     if (!scsi_dh_data) {
> > +             sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
> > +                         ONTAP_NAME);
> > +             return -ENOMEM;
> > +     }
> > +
> > +     scsi_dh_data->scsi_dh = &ontap_dh;
> > +     h = (struct ontap_dh_data *) scsi_dh_data->buf;
> > +     h->state = ONTAP_STATE_ACTIVE;
> > +
> > +     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", ONTAP_NAME);
> > +
> > +     try_module_get(THIS_MODULE);
> > +
> > +     return 0;
> > +}
> > +
> > +static void ontap_bus_detach(struct scsi_device *sdev)
> > +{
> > +     struct scsi_dh_data *scsi_dh_data;
> > +     unsigned long flags;
> > +
> > +     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, "%s: Detached\n",
> > +                 ONTAP_NAME);
> > +
> > +     kfree(scsi_dh_data);
> > +     module_put(THIS_MODULE);
> > +}
> > +
> > +static int __init ontap_init(void)
> > +{
> > +     int r;
> > +
> > +     r = scsi_register_device_handler(&ontap_dh);
> > +     if (r != 0)
> > +             printk(KERN_ERR "%s: Failed to register scsi device 
> handler.",
> > +                     ONTAP_NAME);
> > +     return r;
> > +}
> > +
> > +static void __exit ontap_exit(void)
> > +{
> > +     scsi_unregister_device_handler(&ontap_dh);
> > +}
> > +
> > +module_init(ontap_init);
> > +module_exit(ontap_exit);
> > +
> > +MODULE_DESCRIPTION("NetApp controller driver");
> > +MODULE_AUTHOR("Martin George <marting@netapp.com>");
> > +MODULE_LICENSE("GPL");
>