ClabureDB: Classified Bug-Reports Database

   /*
    *
    *                        Linux MegaRAID device driver
    *
    * Copyright (c) 2003-2004  LSI Logic Corporation.
    *
    *           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 of the License, or (at your option) any later version.
   *
   * FILE                : megaraid_mbox.c
   * Version        : v2.20.5.1 (Nov 16 2006)
   *
   * Authors:
   *         Atul Mukker                <Atul.Mukker@lsi.com>
   *         Sreenivas Bagalkote        <Sreenivas.Bagalkote@lsi.com>
   *         Manoj Jose                <Manoj.Jose@lsi.com>
   *         Seokmann Ju
   *
   * List of supported controllers
   *
   * OEM        Product Name                        VID        DID        SSVID        SSID
   * ---        ------------                        ---        ---        ----        ----
   * Dell PERC3/QC                        101E        1960        1028        0471
   * Dell PERC3/DC                        101E        1960        1028        0493
   * Dell PERC3/SC                        101E        1960        1028        0475
   * Dell PERC3/Di                        1028        1960        1028        0123
   * Dell PERC4/SC                        1000        1960        1028        0520
   * Dell PERC4/DC                        1000        1960        1028        0518
   * Dell PERC4/QC                        1000        0407        1028        0531
   * Dell PERC4/Di                        1028        000F        1028        014A
   * Dell PERC 4e/Si                        1028        0013        1028        016c
   * Dell PERC 4e/Di                        1028        0013        1028        016d
   * Dell PERC 4e/Di                        1028        0013        1028        016e
   * Dell PERC 4e/Di                        1028        0013        1028        016f
   * Dell PERC 4e/Di                        1028        0013        1028        0170
   * Dell PERC 4e/DC                        1000        0408        1028        0002
   * Dell PERC 4e/SC                        1000        0408        1028        0001
   *
   *
   * LSI MegaRAID SCSI 320-0                1000        1960        1000        A520
   * LSI MegaRAID SCSI 320-1                1000        1960        1000        0520
   * LSI MegaRAID SCSI 320-2                1000        1960        1000        0518
   * LSI MegaRAID SCSI 320-0X                1000        0407        1000        0530
   * LSI MegaRAID SCSI 320-2X                1000        0407        1000        0532
   * LSI MegaRAID SCSI 320-4X                1000        0407        1000        0531
   * LSI MegaRAID SCSI 320-1E                1000        0408        1000        0001
   * LSI MegaRAID SCSI 320-2E                1000        0408        1000        0002
   * LSI MegaRAID SATA 150-4                1000        1960        1000        4523
   * LSI MegaRAID SATA 150-6                1000        1960        1000        0523
   * LSI MegaRAID SATA 300-4X                1000        0409        1000        3004
   * LSI MegaRAID SATA 300-8X                1000        0409        1000        3008
   *
   * INTEL RAID Controller SRCU42X        1000        0407        8086        0532
   * INTEL RAID Controller SRCS16                1000        1960        8086        0523
   * INTEL RAID Controller SRCU42E        1000        0408        8086        0002
   * INTEL RAID Controller SRCZCRX        1000        0407        8086        0530
   * INTEL RAID Controller SRCS28X        1000        0409        8086        3008
   * INTEL RAID Controller SROMBU42E        1000        0408        8086        3431
   * INTEL RAID Controller SROMBU42E        1000        0408        8086        3499
   * INTEL RAID Controller SRCU51L        1000        1960        8086        0520
   *
   * FSC        MegaRAID PCI Express ROMB        1000        0408        1734        1065
   *
   * ACER        MegaRAID ROMB-2E                1000        0408        1025        004D
   *
   * NEC        MegaRAID PCI Express ROMB        1000        0408        1033        8287
   *
   * For history of changes, see Documentation/ChangeLog.megaraid
   */
  
  #include "megaraid_mbox.h"
  
  static int megaraid_init(void);
  static void megaraid_exit(void);
  
  static int megaraid_probe_one(struct pci_dev*, const struct pci_device_id *);
  static void megaraid_detach_one(struct pci_dev *);
  static void megaraid_mbox_shutdown(struct pci_dev *);
  
  static int megaraid_io_attach(adapter_t *);
  static void megaraid_io_detach(adapter_t *);
  
  static int megaraid_init_mbox(adapter_t *);
  static void megaraid_fini_mbox(adapter_t *);
  
  static int megaraid_alloc_cmd_packets(adapter_t *);
  static void megaraid_free_cmd_packets(adapter_t *);
  
  static int megaraid_mbox_setup_dma_pools(adapter_t *);
  static void megaraid_mbox_teardown_dma_pools(adapter_t *);
  
  static int megaraid_sysfs_alloc_resources(adapter_t *);
  static void megaraid_sysfs_free_resources(adapter_t *);
  
  static int megaraid_abort_handler(struct scsi_cmnd *);
  static int megaraid_reset_handler(struct scsi_cmnd *);
  
 static int mbox_post_sync_cmd(adapter_t *, uint8_t []);
 static int mbox_post_sync_cmd_fast(adapter_t *, uint8_t []);
 static int megaraid_busywait_mbox(mraid_device_t *);
 static int megaraid_mbox_product_info(adapter_t *);
 static int megaraid_mbox_extended_cdb(adapter_t *);
 static int megaraid_mbox_support_ha(adapter_t *, uint16_t *);
 static int megaraid_mbox_support_random_del(adapter_t *);
 static int megaraid_mbox_get_max_sg(adapter_t *);
 static void megaraid_mbox_enum_raid_scsi(adapter_t *);
 static void megaraid_mbox_flush_cache(adapter_t *);
 static int megaraid_mbox_fire_sync_cmd(adapter_t *);
 
 static void megaraid_mbox_display_scb(adapter_t *, scb_t *);
 static void megaraid_mbox_setup_device_map(adapter_t *);
 
 static int megaraid_queue_command(struct scsi_cmnd *,
                 void (*)(struct scsi_cmnd *));
 static scb_t *megaraid_mbox_build_cmd(adapter_t *, struct scsi_cmnd *, int *);
 static void megaraid_mbox_runpendq(adapter_t *, scb_t *);
 static void megaraid_mbox_prepare_pthru(adapter_t *, scb_t *,
                 struct scsi_cmnd *);
 static void megaraid_mbox_prepare_epthru(adapter_t *, scb_t *,
                 struct scsi_cmnd *);
 
 static irqreturn_t megaraid_isr(int, void *);
 
 static void megaraid_mbox_dpc(unsigned long);
 
 static ssize_t megaraid_sysfs_show_app_hndl(struct device *, struct device_attribute *attr, char *);
 static ssize_t megaraid_sysfs_show_ldnum(struct device *, struct device_attribute *attr, char *);
 
 static int megaraid_cmm_register(adapter_t *);
 static int megaraid_cmm_unregister(adapter_t *);
 static int megaraid_mbox_mm_handler(unsigned long, uioc_t *, uint32_t);
 static int megaraid_mbox_mm_command(adapter_t *, uioc_t *);
 static void megaraid_mbox_mm_done(adapter_t *, scb_t *);
 static int gather_hbainfo(adapter_t *, mraid_hba_info_t *);
 static int wait_till_fw_empty(adapter_t *);
 
 
 
 MODULE_AUTHOR("megaraidlinux@lsi.com");
 MODULE_DESCRIPTION("LSI Logic MegaRAID Mailbox Driver");
 MODULE_LICENSE("GPL");
 MODULE_VERSION(MEGARAID_VERSION);
 
 /*
  * ### modules parameters for driver ###
  */
 
 /*
  * Set to enable driver to expose unconfigured disk to kernel
  */
 static int megaraid_expose_unconf_disks = 0;
 module_param_named(unconf_disks, megaraid_expose_unconf_disks, int, 0);
 MODULE_PARM_DESC(unconf_disks,
         "Set to expose unconfigured disks to kernel (default=0)");
 
 /*
  * driver wait time if the adapter's mailbox is busy
  */
 static unsigned int max_mbox_busy_wait = MBOX_BUSY_WAIT;
 module_param_named(busy_wait, max_mbox_busy_wait, int, 0);
 MODULE_PARM_DESC(busy_wait,
         "Max wait for mailbox in microseconds if busy (default=10)");
 
 /*
  * number of sectors per IO command
  */
 static unsigned int megaraid_max_sectors = MBOX_MAX_SECTORS;
 module_param_named(max_sectors, megaraid_max_sectors, int, 0);
 MODULE_PARM_DESC(max_sectors,
         "Maximum number of sectors per IO command (default=128)");
 
 /*
  * number of commands per logical unit
  */
 static unsigned int megaraid_cmd_per_lun = MBOX_DEF_CMD_PER_LUN;
 module_param_named(cmd_per_lun, megaraid_cmd_per_lun, int, 0);
 MODULE_PARM_DESC(cmd_per_lun,
         "Maximum number of commands per logical unit (default=64)");
 
 
 /*
  * Fast driver load option, skip scanning for physical devices during load.
  * This would result in non-disk devices being skipped during driver load
  * time. These can be later added though, using /proc/scsi/scsi
  */
 static unsigned int megaraid_fast_load = 0;
 module_param_named(fast_load, megaraid_fast_load, int, 0);
 MODULE_PARM_DESC(fast_load,
         "Faster loading of the driver, skips physical devices! (default=0)");
 
 
 /*
  * mraid_debug level - threshold for amount of information to be displayed by
  * the driver. This level can be changed through modules parameters, ioctl or
  * sysfs/proc interface. By default, print the announcement messages only.
  */
 int mraid_debug_level = CL_ANN;
 module_param_named(debug_level, mraid_debug_level, int, 0);
 MODULE_PARM_DESC(debug_level, "Debug level for driver (default=0)");
 
 /*
  * ### global data ###
  */
 static uint8_t megaraid_mbox_version[8] =
         { 0x02, 0x20, 0x04, 0x06, 3, 7, 20, 5 };
 
 
 /*
  * PCI table for all supported controllers.
  */
 static struct pci_device_id pci_id_table_g[] =  {
         {
                 PCI_VENDOR_ID_DELL,
                 PCI_DEVICE_ID_PERC4_DI_DISCOVERY,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4_DI_DISCOVERY,
         },
         {
                 PCI_VENDOR_ID_LSI_LOGIC,
                 PCI_DEVICE_ID_PERC4_SC,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4_SC,
         },
         {
                 PCI_VENDOR_ID_LSI_LOGIC,
                 PCI_DEVICE_ID_PERC4_DC,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4_DC,
         },
         {
                 PCI_VENDOR_ID_LSI_LOGIC,
                 PCI_DEVICE_ID_VERDE,
                 PCI_ANY_ID,
                 PCI_ANY_ID,
         },
         {
                 PCI_VENDOR_ID_DELL,
                 PCI_DEVICE_ID_PERC4_DI_EVERGLADES,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4_DI_EVERGLADES,
         },
         {
                 PCI_VENDOR_ID_DELL,
                 PCI_DEVICE_ID_PERC4E_SI_BIGBEND,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4E_SI_BIGBEND,
         },
         {
                 PCI_VENDOR_ID_DELL,
                 PCI_DEVICE_ID_PERC4E_DI_KOBUK,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4E_DI_KOBUK,
         },
         {
                 PCI_VENDOR_ID_DELL,
                 PCI_DEVICE_ID_PERC4E_DI_CORVETTE,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4E_DI_CORVETTE,
         },
         {
                 PCI_VENDOR_ID_DELL,
                 PCI_DEVICE_ID_PERC4E_DI_EXPEDITION,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4E_DI_EXPEDITION,
         },
         {
                 PCI_VENDOR_ID_DELL,
                 PCI_DEVICE_ID_PERC4E_DI_GUADALUPE,
                 PCI_VENDOR_ID_DELL,
                 PCI_SUBSYS_ID_PERC4E_DI_GUADALUPE,
         },
         {
                 PCI_VENDOR_ID_LSI_LOGIC,
                 PCI_DEVICE_ID_DOBSON,
                 PCI_ANY_ID,
                 PCI_ANY_ID,
         },
         {
                 PCI_VENDOR_ID_AMI,
                 PCI_DEVICE_ID_AMI_MEGARAID3,
                 PCI_ANY_ID,
                 PCI_ANY_ID,
         },
         {
                 PCI_VENDOR_ID_LSI_LOGIC,
                 PCI_DEVICE_ID_AMI_MEGARAID3,
                 PCI_ANY_ID,
                 PCI_ANY_ID,
         },
         {
                 PCI_VENDOR_ID_LSI_LOGIC,
                 PCI_DEVICE_ID_LINDSAY,
                 PCI_ANY_ID,
                 PCI_ANY_ID,
         },
         {0}        /* Terminating entry */
 };
 MODULE_DEVICE_TABLE(pci, pci_id_table_g);
 
 
 static struct pci_driver megaraid_pci_driver = {
         .name                = "megaraid",
         .id_table        = pci_id_table_g,
         .probe                = megaraid_probe_one,
         .remove                = __devexit_p(megaraid_detach_one),
         .shutdown        = megaraid_mbox_shutdown,
 };
 
 
 
 // definitions for the device attributes for exporting logical drive number
 // for a scsi address (Host, Channel, Id, Lun)
 
 DEVICE_ATTR(megaraid_mbox_app_hndl, S_IRUSR, megaraid_sysfs_show_app_hndl,
                 NULL);
 
 // Host template initializer for megaraid mbox sysfs device attributes
 static struct device_attribute *megaraid_shost_attrs[] = {
         &dev_attr_megaraid_mbox_app_hndl,
         NULL,
 };
 
 
 DEVICE_ATTR(megaraid_mbox_ld, S_IRUSR, megaraid_sysfs_show_ldnum, NULL);
 
 // Host template initializer for megaraid mbox sysfs device attributes
 static struct device_attribute *megaraid_sdev_attrs[] = {
         &dev_attr_megaraid_mbox_ld,
         NULL,
 };
 
 /**
  * megaraid_change_queue_depth - Change the device's queue depth
  * @sdev:        scsi device struct
  * @qdepth:        depth to set
  *
  * Return value:
  *         actual depth set
  */
 static int megaraid_change_queue_depth(struct scsi_device *sdev, int qdepth)
 {
         if (qdepth > MBOX_MAX_SCSI_CMDS)
                 qdepth = MBOX_MAX_SCSI_CMDS;
         scsi_adjust_queue_depth(sdev, 0, qdepth);
         return sdev->queue_depth;
 }
 
 /*
  * Scsi host template for megaraid unified driver
  */
 static struct scsi_host_template megaraid_template_g = {
         .module                                = THIS_MODULE,
         .name                                = "LSI Logic MegaRAID driver",
         .proc_name                        = "megaraid",
         .queuecommand                        = megaraid_queue_command,
         .eh_abort_handler                = megaraid_abort_handler,
         .eh_device_reset_handler        = megaraid_reset_handler,
         .eh_bus_reset_handler                = megaraid_reset_handler,
         .eh_host_reset_handler                = megaraid_reset_handler,
         .change_queue_depth                = megaraid_change_queue_depth,
         .use_clustering                        = ENABLE_CLUSTERING,
         .sdev_attrs                        = megaraid_sdev_attrs,
         .shost_attrs                        = megaraid_shost_attrs,
 };
 
 
 /**
  * megaraid_init - module load hook
  *
  * We register ourselves as hotplug enabled module and let PCI subsystem
  * discover our adapters.
  */
 static int __init
 megaraid_init(void)
 {
         int        rval;
 
         // Announce the driver version
         con_log(CL_ANN, (KERN_INFO "megaraid: %s %s\n", MEGARAID_VERSION,
                 MEGARAID_EXT_VERSION));
 
         // check validity of module parameters
         if (megaraid_cmd_per_lun > MBOX_MAX_SCSI_CMDS) {
 
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid mailbox: max commands per lun reset to %d\n",
                         MBOX_MAX_SCSI_CMDS));
 
                 megaraid_cmd_per_lun = MBOX_MAX_SCSI_CMDS;
         }
 
 
         // register as a PCI hot-plug driver module
         rval = pci_register_driver(&megaraid_pci_driver);
         if (rval < 0) {
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid: could not register hotplug support.\n"));
         }
 
         return rval;
 }
 
 
 /**
  * megaraid_exit - driver unload entry point
  *
  * We simply unwrap the megaraid_init routine here.
  */
 static void __exit
 megaraid_exit(void)
 {
         con_log(CL_DLEVEL1, (KERN_NOTICE "megaraid: unloading framework\n"));
 
         // unregister as PCI hotplug driver
         pci_unregister_driver(&megaraid_pci_driver);
 
         return;
 }
 
 
 /**
  * megaraid_probe_one - PCI hotplug entry point
  * @pdev        : handle to this controller's PCI configuration space
  * @id                : pci device id of the class of controllers
  *
  * This routine should be called whenever a new adapter is detected by the
  * PCI hotplug susbsystem.
  */
 static int __devinit
 megaraid_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 {
         adapter_t        *adapter;
 
 
         // detected a new controller
         con_log(CL_ANN, (KERN_INFO
                 "megaraid: probe new device %#4.04x:%#4.04x:%#4.04x:%#4.04x: ",
                 pdev->vendor, pdev->device, pdev->subsystem_vendor,
                 pdev->subsystem_device));
 
         con_log(CL_ANN, ("bus %d:slot %d:func %d\n", pdev->bus->number,
                 PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn)));
 
         if (pci_enable_device(pdev)) {
                 con_log(CL_ANN, (KERN_WARNING
                                 "megaraid: pci_enable_device failed\n"));
 
                 return -ENODEV;
         }
 
         // Enable bus-mastering on this controller
         pci_set_master(pdev);
 
         // Allocate the per driver initialization structure
         adapter = kzalloc(sizeof(adapter_t), GFP_KERNEL);
 
         if (adapter == NULL) {
                 con_log(CL_ANN, (KERN_WARNING
                 "megaraid: out of memory, %s %d.\n", __func__, __LINE__));
 
                 goto out_probe_one;
         }
 
 
         // set up PCI related soft state and other pre-known parameters
         adapter->unique_id        = pdev->bus->number << 8 | pdev->devfn;
         adapter->irq                = pdev->irq;
         adapter->pdev                = pdev;
 
         atomic_set(&adapter->being_detached, 0);
 
         // Setup the default DMA mask. This would be changed later on
         // depending on hardware capabilities
         if (pci_set_dma_mask(adapter->pdev, DMA_32BIT_MASK) != 0) {
 
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid: pci_set_dma_mask failed:%d\n", __LINE__));
 
                 goto out_free_adapter;
         }
 
 
         // Initialize the synchronization lock for kernel and LLD
         spin_lock_init(&adapter->lock);
 
         // Initialize the command queues: the list of free SCBs and the list
         // of pending SCBs.
         INIT_LIST_HEAD(&adapter->kscb_pool);
         spin_lock_init(SCSI_FREE_LIST_LOCK(adapter));
 
         INIT_LIST_HEAD(&adapter->pend_list);
         spin_lock_init(PENDING_LIST_LOCK(adapter));
 
         INIT_LIST_HEAD(&adapter->completed_list);
         spin_lock_init(COMPLETED_LIST_LOCK(adapter));
 
 
         // Start the mailbox based controller
         if (megaraid_init_mbox(adapter) != 0) {
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid: maibox adapter did not initialize\n"));
 
                 goto out_free_adapter;
         }
 
         // Register with LSI Common Management Module
         if (megaraid_cmm_register(adapter) != 0) {
 
                 con_log(CL_ANN, (KERN_WARNING
                 "megaraid: could not register with management module\n"));
 
                 goto out_fini_mbox;
         }
 
         // setup adapter handle in PCI soft state
         pci_set_drvdata(pdev, adapter);
 
         // attach with scsi mid-layer
         if (megaraid_io_attach(adapter) != 0) {
 
                 con_log(CL_ANN, (KERN_WARNING "megaraid: io attach failed\n"));
 
                 goto out_cmm_unreg;
         }
 
         return 0;
 
 out_cmm_unreg:
         pci_set_drvdata(pdev, NULL);
         megaraid_cmm_unregister(adapter);
 out_fini_mbox:
         megaraid_fini_mbox(adapter);
 out_free_adapter:
         kfree(adapter);
 out_probe_one:
         pci_disable_device(pdev);
 
         return -ENODEV;
 }
 
 
 /**
  * megaraid_detach_one - release framework resources and call LLD release routine
  * @pdev        : handle for our PCI cofiguration space
  *
  * This routine is called during driver unload. We free all the allocated
  * resources and call the corresponding LLD so that it can also release all
  * its resources.
  *
  * This routine is also called from the PCI hotplug system.
  */
 static void
 megaraid_detach_one(struct pci_dev *pdev)
 {
         adapter_t                *adapter;
         struct Scsi_Host        *host;
 
 
         // Start a rollback on this adapter
         adapter = pci_get_drvdata(pdev);
 
         if (!adapter) {
                 con_log(CL_ANN, (KERN_CRIT
                 "megaraid: Invalid detach on %#4.04x:%#4.04x:%#4.04x:%#4.04x\n",
                         pdev->vendor, pdev->device, pdev->subsystem_vendor,
                         pdev->subsystem_device));
 
                 return;
         }
         else {
                 con_log(CL_ANN, (KERN_NOTICE
                 "megaraid: detaching device %#4.04x:%#4.04x:%#4.04x:%#4.04x\n",
                         pdev->vendor, pdev->device, pdev->subsystem_vendor,
                         pdev->subsystem_device));
         }
 
 
         host = adapter->host;
 
         // do not allow any more requests from the management module for this
         // adapter.
         // FIXME: How do we account for the request which might still be
         // pending with us?
         atomic_set(&adapter->being_detached, 1);
 
         // detach from the IO sub-system
         megaraid_io_detach(adapter);
 
         // reset the device state in the PCI structure. We check this
         // condition when we enter here. If the device state is NULL,
         // that would mean the device has already been removed
         pci_set_drvdata(pdev, NULL);
 
         // Unregister from common management module
         //
         // FIXME: this must return success or failure for conditions if there
         // is a command pending with LLD or not.
         megaraid_cmm_unregister(adapter);
 
         // finalize the mailbox based controller and release all resources
         megaraid_fini_mbox(adapter);
 
         kfree(adapter);
 
         scsi_host_put(host);
 
         pci_disable_device(pdev);
 
         return;
 }
 
 
 /**
  * megaraid_mbox_shutdown - PCI shutdown for megaraid HBA
  * @pdev                : generic driver model device
  *
  * Shutdown notification, perform flush cache.
  */
 static void
 megaraid_mbox_shutdown(struct pci_dev *pdev)
 {
         adapter_t                *adapter = pci_get_drvdata(pdev);
         static int                counter;
 
         if (!adapter) {
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid: null device in shutdown\n"));
                 return;
         }
 
         // flush caches now
         con_log(CL_ANN, (KERN_INFO "megaraid: flushing adapter %d...",
                 counter++));
 
         megaraid_mbox_flush_cache(adapter);
 
         con_log(CL_ANN, ("done\n"));
 }
 
 
 /**
  * megaraid_io_attach - attach a device with the IO subsystem
  * @adapter                : controller's soft state
  *
  * Attach this device with the IO subsystem.
  */
 static int
 megaraid_io_attach(adapter_t *adapter)
 {
         struct Scsi_Host        *host;
 
         // Initialize SCSI Host structure
         host = scsi_host_alloc(&megaraid_template_g, 8);
         if (!host) {
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid mbox: scsi_register failed\n"));
 
                 return -1;
         }
 
         SCSIHOST2ADAP(host)        = (caddr_t)adapter;
         adapter->host                = host;
 
         host->irq                = adapter->irq;
         host->unique_id                = adapter->unique_id;
         host->can_queue                = adapter->max_cmds;
         host->this_id                = adapter->init_id;
         host->sg_tablesize        = adapter->sglen;
         host->max_sectors        = adapter->max_sectors;
         host->cmd_per_lun        = adapter->cmd_per_lun;
         host->max_channel        = adapter->max_channel;
         host->max_id                = adapter->max_target;
         host->max_lun                = adapter->max_lun;
 
 
         // notify mid-layer about the new controller
         if (scsi_add_host(host, &adapter->pdev->dev)) {
 
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid mbox: scsi_add_host failed\n"));
 
                 scsi_host_put(host);
 
                 return -1;
         }
 
         scsi_scan_host(host);
 
         return 0;
 }
 
 
 /**
  * megaraid_io_detach - detach a device from the IO subsystem
  * @adapter                : controller's soft state
  *
  * Detach this device from the IO subsystem.
  */
 static void
 megaraid_io_detach(adapter_t *adapter)
 {
         struct Scsi_Host        *host;
 
         con_log(CL_DLEVEL1, (KERN_INFO "megaraid: io detach\n"));
 
         host = adapter->host;
 
         scsi_remove_host(host);
 
         return;
 }
 
 
 /*
  * START: Mailbox Low Level Driver
  *
  * This is section specific to the single mailbox based controllers
  */
 
 /**
  * megaraid_init_mbox - initialize controller
  * @adapter                : our soft state
  *
  * - Allocate 16-byte aligned mailbox memory for firmware handshake
  * - Allocate controller's memory resources
  * - Find out all initialization data
  * - Allocate memory required for all the commands
  * - Use internal library of FW routines, build up complete soft state
  */
 static int __devinit
 megaraid_init_mbox(adapter_t *adapter)
 {
         struct pci_dev                *pdev;
         mraid_device_t                *raid_dev;
         int                        i;
         uint32_t                magic64;
 
 
         adapter->ito        = MBOX_TIMEOUT;
         pdev                = adapter->pdev;
 
         /*
          * Allocate and initialize the init data structure for mailbox
          * controllers
          */
         raid_dev = kzalloc(sizeof(mraid_device_t), GFP_KERNEL);
         if (raid_dev == NULL) return -1;
 
 
         /*
          * Attach the adapter soft state to raid device soft state
          */
         adapter->raid_device        = (caddr_t)raid_dev;
         raid_dev->fast_load        = megaraid_fast_load;
 
 
         // our baseport
         raid_dev->baseport = pci_resource_start(pdev, 0);
 
         if (pci_request_regions(pdev, "MegaRAID: LSI Logic Corporation") != 0) {
 
                 con_log(CL_ANN, (KERN_WARNING
                                 "megaraid: mem region busy\n"));
 
                 goto out_free_raid_dev;
         }
 
         raid_dev->baseaddr = ioremap_nocache(raid_dev->baseport, 128);
 
         if (!raid_dev->baseaddr) {
 
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid: could not map hba memory\n") );
 
                 goto out_release_regions;
         }
 
         /* initialize the mutual exclusion lock for the mailbox */
         spin_lock_init(&raid_dev->mailbox_lock);
 
         /* allocate memory required for commands */
         if (megaraid_alloc_cmd_packets(adapter) != 0)
                 goto out_iounmap;
 
         /*
          * Issue SYNC cmd to flush the pending cmds in the adapter
          * and initialize its internal state
          */
 
         if (megaraid_mbox_fire_sync_cmd(adapter))
                 con_log(CL_ANN, ("megaraid: sync cmd failed\n"));
 
         /*
          * Setup the rest of the soft state using the library of
          * FW routines
          */
 
         /* request IRQ and register the interrupt service routine */
         if (request_irq(adapter->irq, megaraid_isr, IRQF_SHARED, "megaraid",
                 adapter)) {
 
                 con_log(CL_ANN, (KERN_WARNING
                         "megaraid: Couldn't register IRQ %d!\n", adapter->irq));
                 goto out_alloc_cmds;
 
         }
 
         // Product info
         if (megaraid_mbox_product_info(adapter) != 0)
                 goto out_free_irq;
 
         // Do we support extended CDBs
         adapter->max_cdb_sz = 10;
         if (megaraid_mbox_extended_cdb(adapter) == 0) {
                 adapter->max_cdb_sz = 16;
         }
 
         /*
          * Do we support cluster environment, if we do, what is the initiator
          * id.
          * NOTE: In a non-cluster aware firmware environment, the LLD should
          * return 7 as initiator id.
          */
         adapter->ha                = 0;
         adapter->init_id        = -1;
         if (megaraid_mbox_support_ha(adapter, &adapter->init_id) == 0) {
                 adapter->ha = 1;
         }
 
         /*
          * Prepare the device ids array to have the mapping between the kernel
          * device address and megaraid device address.
          * We export the physical devices on their actual addresses. The
          * logical drives are exported on a virtual SCSI channel
          */
         megaraid_mbox_setup_device_map(adapter);
 
         // If the firmware supports random deletion, update the device id map
         if (megaraid_mbox_support_random_del(adapter)) {
 
                 // Change the logical drives numbers in device_ids array one
                 // slot in device_ids is reserved for target id, that's why
                 // "<=" below
                 for (i = 0; i <= MAX_LOGICAL_DRIVES_40LD; i++) {
                         adapter->device_ids[adapter->max_channel][i] += 0x80;
                 }
                 adapter->device_ids[adapter->max_channel][adapter->init_id] =
                         0xFF;
 
                 raid_dev->random_del_supported = 1;
         }
 
         /*
          * find out the maximum number of scatter-gather elements supported by
          * this firmware
          */
         adapter->sglen = megaraid_mbox_get_max_sg(adapter);
 
         // enumerate RAID and SCSI channels so that all devices on SCSI
         // channels can later be exported, including disk devices
         megaraid_mbox_enum_raid_scsi(adapter);
 
         /*
          * Other parameters required by upper layer
          *
          * maximum number of sectors per IO command
          */
         adapter->max_sectors = megaraid_max_sectors;
 
         /*
          * number of queued commands per LUN.
          */
         adapter->cmd_per_lun = megaraid_cmd_per_lun;
 
         /*
          * Allocate resources required to issue FW calls, when sysfs is
          * accessed
          */
         if (megaraid_sysfs_alloc_resources(adapter) != 0)
                 goto out_free_irq;
 
         // Set the DMA mask to 64-bit. All supported controllers as capable of
         // DMA in this range
         pci_read_config_dword(adapter->pdev, PCI_CONF_AMISIG64, &magic64);
 
         if (((magic64 == HBA_SIGNATURE_64_BIT) &&
                 ((adapter->pdev->subsystem_device !=
                 PCI_SUBSYS_ID_MEGARAID_SATA_150_6) &&
                 (adapter->pdev->subsystem_device !=
                 PCI_SUBSYS_ID_MEGARAID_SATA_150_4))) ||
                 (adapter->pdev->vendor == PCI_VENDOR_ID_LSI_LOGIC &&
                 adapter->pdev->device == PCI_DEVICE_ID_VERDE) ||
                 (adapter->pdev->vendor == PCI_VENDOR_ID_LSI_LOGIC &&
                 adapter->pdev->device == PCI_DEVICE_ID_DOBSON) ||
                 (adapter->pdev->vendor == PCI_VENDOR_ID_LSI_LOGIC &&
                 adapter->pdev->device == PCI_DEVICE_ID_LINDSAY) ||
                 (adapter->pdev->vendor == PCI_VENDOR_ID_DELL &&
                 adapter->pdev->device == PCI_DEVICE_ID_PERC4_DI_EVERGLADES) ||
                 (adapter->pdev->vendor == PCI_VENDOR_ID_DELL &&
                 adapter->pdev->device == PCI_DEVICE_ID_PERC4E_DI_KOBUK)) {
                 if (pci_set_dma_mask(adapter->pdev, DMA_64BIT_MASK)) {
                         con_log(CL_ANN, (KERN_WARNING
                                 "megaraid: DMA mask for 64-bit failed\n"));
 
                         if (pci_set_dma_mask (adapter->pdev, DMA_32BIT_MASK)) {
                                 con_log(CL_ANN, (KERN_WARNING
                                         "megaraid: 32-bit DMA mask failed\n"));
                                 goto out_free_sysfs_res;
                         }
                 }
         }
 
         // setup tasklet for DPC
         tasklet_init(&adapter->dpc_h, megaraid_mbox_dpc,
                         (unsigned long)adapter);
 
         con_log(CL_DLEVEL1, (KERN_INFO
                 "megaraid mbox hba successfully initialized\n"));
 
         return 0;
 
 out_free_sysfs_res:
         megaraid_sysfs_free_resources(adapter);
 out_free_irq:
         free_irq(adapter->irq, adapter);
 out_alloc_cmds:
         megaraid_free_cmd_packets(adapter);
 out_iounmap:
         iounmap(raid_dev->baseaddr);
 out_release_regions:
         pci_release_regions(pdev);
 out_free_raid_dev:
         kfree(raid_dev);
 
         return -1;
 }
 
 
 /**
  * megaraid_fini_mbox - undo controller initialization
  * @adapter                : our soft state
  */
 static void
 megaraid_fini_mbox(adapter_t *adapter)
 {
         mraid_device_t *raid_dev = ADAP2RAIDDEV(adapter);
 
         // flush all caches
         megaraid_mbox_flush_cache(adapter);
 
         tasklet_kill(&adapter->dpc_h);
 
         megaraid_sysfs_free_resources(adapter);
 
         megaraid_free_cmd_packets(adapter);
 
         free_irq(adapter->irq, adapter);
 
         iounmap(raid_dev->baseaddr);
 
         pci_release_regions(adapter->pdev);
 
         kfree(raid_dev);
 
         return;
 }
 
 
 /**
  * megaraid_alloc_cmd_packets - allocate shared mailbox
  * @adapter                : soft state of the raid controller
  *
  * Allocate and align the shared mailbox. This maibox is used to issue
  * all the commands. For IO based controllers, the mailbox is also regsitered
  * with the FW. Allocate memory for all commands as well.
  * This is our big allocator.
  */
 static int
 megaraid_alloc_cmd_packets(adapter_t *adapter)
 {
         mraid_device_t                *raid_dev = ADAP2RAIDDEV(adapter);
         struct pci_dev                *pdev;
         unsigned long                align;
         scb_t                        *scb;
         mbox_ccb_t                *ccb;
         struct mraid_pci_blk        *epthru_pci_blk;
         struct mraid_pci_blk        *sg_pci_blk;
         struct mraid_pci_blk        *mbox_pci_blk;
         int                        i;
 
         pdev = adapter->pdev;
 
         /*
          * Setup the mailbox
          * Allocate the common 16-byte aligned memory for the handshake
          * mailbox.
          */
        raid_dev->una_mbox64 = pci_alloc_consistent(adapter->pdev,
                        sizeof(mbox64_t), &raid_dev->una_mbox64_dma);

        if (!raid_dev->una_mbox64) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));
                return -1;
        }
        memset(raid_dev->una_mbox64, 0, sizeof(mbox64_t));

        /*
         * Align the mailbox at 16-byte boundary
         */
        raid_dev->mbox        = &raid_dev->una_mbox64->mbox32;

        raid_dev->mbox        = (mbox_t *)((((unsigned long)raid_dev->mbox) + 15) &
                                (~0UL ^ 0xFUL));

        raid_dev->mbox64 = (mbox64_t *)(((unsigned long)raid_dev->mbox) - 8);

        align = ((void *)raid_dev->mbox -
                        ((void *)&raid_dev->una_mbox64->mbox32));

        raid_dev->mbox_dma = (unsigned long)raid_dev->una_mbox64_dma + 8 +
                        align;

        // Allocate memory for commands issued internally
        adapter->ibuf = pci_alloc_consistent(pdev, MBOX_IBUF_SIZE,
                                &adapter->ibuf_dma_h);
        if (!adapter->ibuf) {

                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));

                goto out_free_common_mbox;
        }
        memset(adapter->ibuf, 0, MBOX_IBUF_SIZE);

        // Allocate memory for our SCSI Command Blocks and their associated
        // memory

        /*
         * Allocate memory for the base list of scb. Later allocate memory for
         * CCBs and embedded components of each CCB and point the pointers in
         * scb to the allocated components
         * NOTE: The code to allocate SCB will be duplicated in all the LLD
         * since the calling routine does not yet know the number of available
         * commands.
         */
        adapter->kscb_list = kcalloc(MBOX_MAX_SCSI_CMDS, sizeof(scb_t), GFP_KERNEL);

        if (adapter->kscb_list == NULL) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));
                goto out_free_ibuf;
        }

        // memory allocation for our command packets
        if (megaraid_mbox_setup_dma_pools(adapter) != 0) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));
                goto out_free_scb_list;
        }

        // Adjust the scb pointers and link in the free pool
        epthru_pci_blk        = raid_dev->epthru_pool;
        sg_pci_blk        = raid_dev->sg_pool;
        mbox_pci_blk        = raid_dev->mbox_pool;

        for (i = 0; i < MBOX_MAX_SCSI_CMDS; i++) {
                scb                        = adapter->kscb_list + i;
                ccb                        = raid_dev->ccb_list + i;

                ccb->mbox        = (mbox_t *)(mbox_pci_blk[i].vaddr + 16);
                ccb->raw_mbox        = (uint8_t *)ccb->mbox;
                ccb->mbox64        = (mbox64_t *)(mbox_pci_blk[i].vaddr + 8);
                ccb->mbox_dma_h        = (unsigned long)mbox_pci_blk[i].dma_addr + 16;

                // make sure the mailbox is aligned properly
                if (ccb->mbox_dma_h & 0x0F) {
                        con_log(CL_ANN, (KERN_CRIT
                                "megaraid mbox: not aligned on 16-bytes\n"));

                        goto out_teardown_dma_pools;
                }

                ccb->epthru                = (mraid_epassthru_t *)
                                                epthru_pci_blk[i].vaddr;
                ccb->epthru_dma_h        = epthru_pci_blk[i].dma_addr;
                ccb->pthru                = (mraid_passthru_t *)ccb->epthru;
                ccb->pthru_dma_h        = ccb->epthru_dma_h;


                ccb->sgl64                = (mbox_sgl64 *)sg_pci_blk[i].vaddr;
                ccb->sgl_dma_h                = sg_pci_blk[i].dma_addr;
                ccb->sgl32                = (mbox_sgl32 *)ccb->sgl64;

                scb->ccb                = (caddr_t)ccb;
                scb->gp                        = 0;

                scb->sno                = i;        // command index

                scb->scp                = NULL;
                scb->state                = SCB_FREE;
                scb->dma_direction        = PCI_DMA_NONE;
                scb->dma_type                = MRAID_DMA_NONE;
                scb->dev_channel        = -1;
                scb->dev_target                = -1;

                // put scb in the free pool
                list_add_tail(&scb->list, &adapter->kscb_pool);
        }

        return 0;

out_teardown_dma_pools:
        megaraid_mbox_teardown_dma_pools(adapter);
out_free_scb_list:
        kfree(adapter->kscb_list);
out_free_ibuf:
        pci_free_consistent(pdev, MBOX_IBUF_SIZE, (void *)adapter->ibuf,
                adapter->ibuf_dma_h);
out_free_common_mbox:
        pci_free_consistent(adapter->pdev, sizeof(mbox64_t),
                (caddr_t)raid_dev->una_mbox64, raid_dev->una_mbox64_dma);

        return -1;
}


/**
 * megaraid_free_cmd_packets - free memory
 * @adapter                : soft state of the raid controller
 *
 * Release memory resources allocated for commands.
 */
static void
megaraid_free_cmd_packets(adapter_t *adapter)
{
        mraid_device_t *raid_dev = ADAP2RAIDDEV(adapter);

        megaraid_mbox_teardown_dma_pools(adapter);

        kfree(adapter->kscb_list);

        pci_free_consistent(adapter->pdev, MBOX_IBUF_SIZE,
                (void *)adapter->ibuf, adapter->ibuf_dma_h);

        pci_free_consistent(adapter->pdev, sizeof(mbox64_t),
                (caddr_t)raid_dev->una_mbox64, raid_dev->una_mbox64_dma);
        return;
}


/**
 * megaraid_mbox_setup_dma_pools - setup dma pool for command packets
 * @adapter                : HBA soft state
 *
 * Setup the dma pools for mailbox, passthru and extended passthru structures,
 * and scatter-gather lists.
 */
static int
megaraid_mbox_setup_dma_pools(adapter_t *adapter)
{
        mraid_device_t                *raid_dev = ADAP2RAIDDEV(adapter);
        struct mraid_pci_blk        *epthru_pci_blk;
        struct mraid_pci_blk        *sg_pci_blk;
        struct mraid_pci_blk        *mbox_pci_blk;
        int                        i;



        // Allocate memory for 16-bytes aligned mailboxes
        raid_dev->mbox_pool_handle = pci_pool_create("megaraid mbox pool",
                                                adapter->pdev,
                                                sizeof(mbox64_t) + 16,
                                                16, 0);

        if (raid_dev->mbox_pool_handle == NULL) {
                goto fail_setup_dma_pool;
        }

        mbox_pci_blk = raid_dev->mbox_pool;
        for (i = 0; i < MBOX_MAX_SCSI_CMDS; i++) {
                mbox_pci_blk[i].vaddr = pci_pool_alloc(
                                                raid_dev->mbox_pool_handle,
                                                GFP_KERNEL,
                                                &mbox_pci_blk[i].dma_addr);
                if (!mbox_pci_blk[i].vaddr) {
                        goto fail_setup_dma_pool;
                }
        }

        /*
         * Allocate memory for each embedded passthru strucuture pointer
         * Request for a 128 bytes aligned structure for each passthru command
         * structure
         * Since passthru and extended passthru commands are exclusive, they
         * share common memory pool. Passthru structures piggyback on memory
         * allocted to extended passthru since passthru is smaller of the two
         */
        raid_dev->epthru_pool_handle = pci_pool_create("megaraid mbox pthru",
                        adapter->pdev, sizeof(mraid_epassthru_t), 128, 0);

        if (raid_dev->epthru_pool_handle == NULL) {
                goto fail_setup_dma_pool;
        }

        epthru_pci_blk = raid_dev->epthru_pool;
        for (i = 0; i < MBOX_MAX_SCSI_CMDS; i++) {
                epthru_pci_blk[i].vaddr = pci_pool_alloc(
                                                raid_dev->epthru_pool_handle,
                                                GFP_KERNEL,
                                                &epthru_pci_blk[i].dma_addr);
                if (!epthru_pci_blk[i].vaddr) {
                        goto fail_setup_dma_pool;
                }
        }


        // Allocate memory for each scatter-gather list. Request for 512 bytes
        // alignment for each sg list
        raid_dev->sg_pool_handle = pci_pool_create("megaraid mbox sg",
                                        adapter->pdev,
                                        sizeof(mbox_sgl64) * MBOX_MAX_SG_SIZE,
                                        512, 0);

        if (raid_dev->sg_pool_handle == NULL) {
                goto fail_setup_dma_pool;
        }

        sg_pci_blk = raid_dev->sg_pool;
        for (i = 0; i < MBOX_MAX_SCSI_CMDS; i++) {
                sg_pci_blk[i].vaddr = pci_pool_alloc(
                                                raid_dev->sg_pool_handle,
                                                GFP_KERNEL,
                                                &sg_pci_blk[i].dma_addr);
                if (!sg_pci_blk[i].vaddr) {
                        goto fail_setup_dma_pool;
                }
        }

        return 0;

fail_setup_dma_pool:
        megaraid_mbox_teardown_dma_pools(adapter);
        return -1;
}


/**
 * megaraid_mbox_teardown_dma_pools - teardown dma pools for command packets
 * @adapter                : HBA soft state
 *
 * Teardown the dma pool for mailbox, passthru and extended passthru
 * structures, and scatter-gather lists.
 */
static void
megaraid_mbox_teardown_dma_pools(adapter_t *adapter)
{
        mraid_device_t                *raid_dev = ADAP2RAIDDEV(adapter);
        struct mraid_pci_blk        *epthru_pci_blk;
        struct mraid_pci_blk        *sg_pci_blk;
        struct mraid_pci_blk        *mbox_pci_blk;
        int                        i;


        sg_pci_blk = raid_dev->sg_pool;
        for (i = 0; i < MBOX_MAX_SCSI_CMDS && sg_pci_blk[i].vaddr; i++) {
                pci_pool_free(raid_dev->sg_pool_handle, sg_pci_blk[i].vaddr,
                        sg_pci_blk[i].dma_addr);
        }
        if (raid_dev->sg_pool_handle)
                pci_pool_destroy(raid_dev->sg_pool_handle);


        epthru_pci_blk = raid_dev->epthru_pool;
        for (i = 0; i < MBOX_MAX_SCSI_CMDS && epthru_pci_blk[i].vaddr; i++) {
                pci_pool_free(raid_dev->epthru_pool_handle,
                        epthru_pci_blk[i].vaddr, epthru_pci_blk[i].dma_addr);
        }
        if (raid_dev->epthru_pool_handle)
                pci_pool_destroy(raid_dev->epthru_pool_handle);


        mbox_pci_blk = raid_dev->mbox_pool;
        for (i = 0; i < MBOX_MAX_SCSI_CMDS && mbox_pci_blk[i].vaddr; i++) {
                pci_pool_free(raid_dev->mbox_pool_handle,
                        mbox_pci_blk[i].vaddr, mbox_pci_blk[i].dma_addr);
        }
        if (raid_dev->mbox_pool_handle)
                pci_pool_destroy(raid_dev->mbox_pool_handle);

        return;
}


/**
 * megaraid_alloc_scb - detach and return a scb from the free list
 * @adapter        : controller's soft state
 * @scp                : pointer to the scsi command to be executed
 *
 * Return the scb from the head of the free list. %NULL if there are none
 * available.
 */
static scb_t *
megaraid_alloc_scb(adapter_t *adapter, struct scsi_cmnd *scp)
{
        struct list_head        *head = &adapter->kscb_pool;
        scb_t                        *scb = NULL;
        unsigned long                flags;

        // detach scb from free pool
        spin_lock_irqsave(SCSI_FREE_LIST_LOCK(adapter), flags);

        if (list_empty(head)) {
                spin_unlock_irqrestore(SCSI_FREE_LIST_LOCK(adapter), flags);
                return NULL;
        }

        scb = list_entry(head->next, scb_t, list);
        list_del_init(&scb->list);

        spin_unlock_irqrestore(SCSI_FREE_LIST_LOCK(adapter), flags);

        scb->state        = SCB_ACTIVE;
        scb->scp        = scp;
        scb->dma_type        = MRAID_DMA_NONE;

        return scb;
}


/**
 * megaraid_dealloc_scb - return the scb to the free pool
 * @adapter        : controller's soft state
 * @scb                : scb to be freed
 *
 * Return the scb back to the free list of scbs. The caller must 'flush' the
 * SCB before calling us. E.g., performing pci_unamp and/or pci_sync etc.
 * NOTE NOTE: Make sure the scb is not on any list before calling this
 * routine.
 */
static inline void
megaraid_dealloc_scb(adapter_t *adapter, scb_t *scb)
{
        unsigned long                flags;

        // put scb in the free pool
        scb->state        = SCB_FREE;
        scb->scp        = NULL;
        spin_lock_irqsave(SCSI_FREE_LIST_LOCK(adapter), flags);

        list_add(&scb->list, &adapter->kscb_pool);

        spin_unlock_irqrestore(SCSI_FREE_LIST_LOCK(adapter), flags);

        return;
}


/**
 * megaraid_mbox_mksgl - make the scatter-gather list
 * @adapter        : controller's soft state
 * @scb                : scsi control block
 *
 * Prepare the scatter-gather list.
 */
static int
megaraid_mbox_mksgl(adapter_t *adapter, scb_t *scb)
{
        struct scatterlist        *sgl;
        mbox_ccb_t                *ccb;
        struct scsi_cmnd        *scp;
        int                        sgcnt;
        int                        i;


        scp        = scb->scp;
        ccb        = (mbox_ccb_t *)scb->ccb;

        sgcnt = scsi_dma_map(scp);
        BUG_ON(sgcnt < 0 || sgcnt > adapter->sglen);

        // no mapping required if no data to be transferred
        if (!sgcnt)
                return 0;

        scb->dma_type = MRAID_DMA_WSG;

        scsi_for_each_sg(scp, sgl, sgcnt, i) {
                ccb->sgl64[i].address        = sg_dma_address(sgl);
                ccb->sgl64[i].length        = sg_dma_len(sgl);
        }

        // Return count of SG nodes
        return sgcnt;
}


/**
 * mbox_post_cmd - issue a mailbox command
 * @adapter        : controller's soft state
 * @scb                : command to be issued
 *
 * Post the command to the controller if mailbox is available.
 */
static int
mbox_post_cmd(adapter_t *adapter, scb_t *scb)
{
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        mbox64_t        *mbox64;
        mbox_t                *mbox;
        mbox_ccb_t        *ccb;
        unsigned long        flags;
        unsigned int        i = 0;


        ccb        = (mbox_ccb_t *)scb->ccb;
        mbox        = raid_dev->mbox;
        mbox64        = raid_dev->mbox64;

        /*
         * Check for busy mailbox. If it is, return failure - the caller
         * should retry later.
         */
        spin_lock_irqsave(MAILBOX_LOCK(raid_dev), flags);

        if (unlikely(mbox->busy)) {
                do {
                        udelay(1);
                        i++;
                        rmb();
                } while(mbox->busy && (i < max_mbox_busy_wait));

                if (mbox->busy) {

                        spin_unlock_irqrestore(MAILBOX_LOCK(raid_dev), flags);

                        return -1;
                }
        }


        // Copy this command's mailbox data into "adapter's" mailbox
        memcpy((caddr_t)mbox64, (caddr_t)ccb->mbox64, 22);
        mbox->cmdid = scb->sno;

        adapter->outstanding_cmds++;

        if (scb->dma_direction == PCI_DMA_TODEVICE)
                pci_dma_sync_sg_for_device(adapter->pdev,
                                           scsi_sglist(scb->scp),
                                           scsi_sg_count(scb->scp),
                                           PCI_DMA_TODEVICE);

        mbox->busy        = 1;        // Set busy
        mbox->poll        = 0;
        mbox->ack        = 0;
        wmb();

        WRINDOOR(raid_dev, raid_dev->mbox_dma | 0x1);

        spin_unlock_irqrestore(MAILBOX_LOCK(raid_dev), flags);

        return 0;
}


/**
 * megaraid_queue_command - generic queue entry point for all LLDs
 * @scp                : pointer to the scsi command to be executed
 * @done        : callback routine to be called after the cmd has be completed
 *
 * Queue entry point for mailbox based controllers.
 */
static int
megaraid_queue_command(struct scsi_cmnd *scp, void (*done)(struct scsi_cmnd *))
{
        adapter_t        *adapter;
        scb_t                *scb;
        int                if_busy;

        adapter                = SCP2ADAPTER(scp);
        scp->scsi_done        = done;
        scp->result        = 0;

        /*
         * Allocate and build a SCB request
         * if_busy flag will be set if megaraid_mbox_build_cmd() command could
         * not allocate scb. We will return non-zero status in that case.
         * NOTE: scb can be null even though certain commands completed
         * successfully, e.g., MODE_SENSE and TEST_UNIT_READY, it would
         * return 0 in that case, and we would do the callback right away.
         */
        if_busy        = 0;
        scb = megaraid_mbox_build_cmd(adapter, scp, &if_busy);
        if (!scb) {        // command already completed
                done(scp);
                return 0;
        }

        megaraid_mbox_runpendq(adapter, scb);
        return if_busy;
}

/**
 * megaraid_mbox_build_cmd - transform the mid-layer scsi commands
 * @adapter        : controller's soft state
 * @scp                : mid-layer scsi command pointer
 * @busy        : set if request could not be completed because of lack of
 *                resources
 *
 * Transform the mid-layer scsi command to megaraid firmware lingua.
 * Convert the command issued by mid-layer to format understood by megaraid
 * firmware. We also complete certain commands without sending them to firmware.
 */
static scb_t *
megaraid_mbox_build_cmd(adapter_t *adapter, struct scsi_cmnd *scp, int *busy)
{
        mraid_device_t                *rdev = ADAP2RAIDDEV(adapter);
        int                        channel;
        int                        target;
        int                        islogical;
        mbox_ccb_t                *ccb;
        mraid_passthru_t        *pthru;
        mbox64_t                *mbox64;
        mbox_t                        *mbox;
        scb_t                        *scb;
        char                        skip[] = "skipping";
        char                        scan[] = "scanning";
        char                        *ss;


        /*
         * Get the appropriate device map for the device this command is
         * intended for
         */
        MRAID_GET_DEVICE_MAP(adapter, scp, channel, target, islogical);

        /*
         * Logical drive commands
         */
        if (islogical) {
                switch (scp->cmnd[0]) {
                case TEST_UNIT_READY:
                        /*
                         * Do we support clustering and is the support enabled
                         * If no, return success always
                         */
                        if (!adapter->ha) {
                                scp->result = (DID_OK << 16);
                                return NULL;
                        }

                        if (!(scb = megaraid_alloc_scb(adapter, scp))) {
                                scp->result = (DID_ERROR << 16);
                                *busy = 1;
                                return NULL;
                        }

                        scb->dma_direction        = scp->sc_data_direction;
                        scb->dev_channel        = 0xFF;
                        scb->dev_target                = target;
                        ccb                        = (mbox_ccb_t *)scb->ccb;

                        /*
                         * The command id will be provided by the command
                         * issuance routine
                         */
                        ccb->raw_mbox[0]        = CLUSTER_CMD;
                        ccb->raw_mbox[2]        = RESERVATION_STATUS;
                        ccb->raw_mbox[3]        = target;

                        return scb;

                case MODE_SENSE:
                {
                        struct scatterlist        *sgl;
                        caddr_t                        vaddr;

                        sgl = scsi_sglist(scp);
                        if (sg_page(sgl)) {
                                vaddr = (caddr_t) sg_virt(&sgl[0]);

                                memset(vaddr, 0, scp->cmnd[4]);
                        }
                        else {
                                con_log(CL_ANN, (KERN_WARNING
                                                 "megaraid mailbox: invalid sg:%d\n",
                                                 __LINE__));
                        }
                }
                scp->result = (DID_OK << 16);
                return NULL;

                case INQUIRY:
                        /*
                         * Display the channel scan for logical drives
                         * Do not display scan for a channel if already done.
                         */
                        if (!(rdev->last_disp & (1L << SCP2CHANNEL(scp)))) {

                                con_log(CL_ANN, (KERN_INFO
                                        "scsi[%d]: scanning scsi channel %d",
                                        adapter->host->host_no,
                                        SCP2CHANNEL(scp)));

                                con_log(CL_ANN, (
                                        " [virtual] for logical drives\n"));

                                rdev->last_disp |= (1L << SCP2CHANNEL(scp));
                        }

                        if (scp->cmnd[1] & MEGA_SCSI_INQ_EVPD) {
                                scp->sense_buffer[0] = 0x70;
                                scp->sense_buffer[2] = ILLEGAL_REQUEST;
                                scp->sense_buffer[12] = MEGA_INVALID_FIELD_IN_CDB;
                                scp->result = CHECK_CONDITION << 1;
                                return NULL;
                        }

                        /* Fall through */

                case READ_CAPACITY:
                        /*
                         * Do not allow LUN > 0 for logical drives and
                         * requests for more than 40 logical drives
                         */
                        if (SCP2LUN(scp)) {
                                scp->result = (DID_BAD_TARGET << 16);
                                return NULL;
                        }
                        if ((target % 0x80) >= MAX_LOGICAL_DRIVES_40LD) {
                                scp->result = (DID_BAD_TARGET << 16);
                                return NULL;
                        }


                        /* Allocate a SCB and initialize passthru */
                        if (!(scb = megaraid_alloc_scb(adapter, scp))) {
                                scp->result = (DID_ERROR << 16);
                                *busy = 1;
                                return NULL;
                        }

                        ccb                        = (mbox_ccb_t *)scb->ccb;
                        scb->dev_channel        = 0xFF;
                        scb->dev_target                = target;
                        pthru                        = ccb->pthru;
                        mbox                        = ccb->mbox;
                        mbox64                        = ccb->mbox64;

                        pthru->timeout                = 0;
                        pthru->ars                = 1;
                        pthru->reqsenselen        = 14;
                        pthru->islogical        = 1;
                        pthru->logdrv                = target;
                        pthru->cdblen                = scp->cmd_len;
                        memcpy(pthru->cdb, scp->cmnd, scp->cmd_len);

                        mbox->cmd                = MBOXCMD_PASSTHRU64;
                        scb->dma_direction        = scp->sc_data_direction;

                        pthru->dataxferlen        = scsi_bufflen(scp);
                        pthru->dataxferaddr        = ccb->sgl_dma_h;
                        pthru->numsge                = megaraid_mbox_mksgl(adapter,
                                                        scb);

                        mbox->xferaddr                = 0xFFFFFFFF;
                        mbox64->xferaddr_lo        = (uint32_t )ccb->pthru_dma_h;
                        mbox64->xferaddr_hi        = 0;

                        return scb;

                case READ_6:
                case WRITE_6:
                case READ_10:
                case WRITE_10:
                case READ_12:
                case WRITE_12:

                        /*
                         * Allocate a SCB and initialize mailbox
                         */
                        if (!(scb = megaraid_alloc_scb(adapter, scp))) {
                                scp->result = (DID_ERROR << 16);
                                *busy = 1;
                                return NULL;
                        }
                        ccb                        = (mbox_ccb_t *)scb->ccb;
                        scb->dev_channel        = 0xFF;
                        scb->dev_target                = target;
                        mbox                        = ccb->mbox;
                        mbox64                        = ccb->mbox64;
                        mbox->logdrv                = target;

                        /*
                         * A little HACK: 2nd bit is zero for all scsi read
                         * commands and is set for all scsi write commands
                         */
                        mbox->cmd = (scp->cmnd[0] & 0x02) ?  MBOXCMD_LWRITE64:
                                        MBOXCMD_LREAD64 ;

                        /*
                         * 6-byte READ(0x08) or WRITE(0x0A) cdb
                         */
                        if (scp->cmd_len == 6) {
                                mbox->numsectors = (uint32_t)scp->cmnd[4];
                                mbox->lba =
                                        ((uint32_t)scp->cmnd[1] << 16)        |
                                        ((uint32_t)scp->cmnd[2] << 8)        |
                                        (uint32_t)scp->cmnd[3];

                                mbox->lba &= 0x1FFFFF;
                        }

                        /*
                         * 10-byte READ(0x28) or WRITE(0x2A) cdb
                         */
                        else if (scp->cmd_len == 10) {
                                mbox->numsectors =
                                        (uint32_t)scp->cmnd[8] |
                                        ((uint32_t)scp->cmnd[7] << 8);
                                mbox->lba =
                                        ((uint32_t)scp->cmnd[2] << 24) |
                                        ((uint32_t)scp->cmnd[3] << 16) |
                                        ((uint32_t)scp->cmnd[4] << 8) |
                                        (uint32_t)scp->cmnd[5];
                        }

                        /*
                         * 12-byte READ(0xA8) or WRITE(0xAA) cdb
                         */
                        else if (scp->cmd_len == 12) {
                                mbox->lba =
                                        ((uint32_t)scp->cmnd[2] << 24) |
                                        ((uint32_t)scp->cmnd[3] << 16) |
                                        ((uint32_t)scp->cmnd[4] << 8) |
                                        (uint32_t)scp->cmnd[5];

                                mbox->numsectors =
                                        ((uint32_t)scp->cmnd[6] << 24) |
                                        ((uint32_t)scp->cmnd[7] << 16) |
                                        ((uint32_t)scp->cmnd[8] << 8) |
                                        (uint32_t)scp->cmnd[9];
                        }
                        else {
                                con_log(CL_ANN, (KERN_WARNING
                                        "megaraid: unsupported CDB length\n"));

                                megaraid_dealloc_scb(adapter, scb);

                                scp->result = (DID_ERROR << 16);
                                return NULL;
                        }

                        scb->dma_direction = scp->sc_data_direction;

                        // Calculate Scatter-Gather info
                        mbox64->xferaddr_lo        = (uint32_t )ccb->sgl_dma_h;
                        mbox->numsge                = megaraid_mbox_mksgl(adapter,
                                                        scb);
                        mbox->xferaddr                = 0xFFFFFFFF;
                        mbox64->xferaddr_hi        = 0;

                        return scb;

                case RESERVE:
                case RELEASE:
                        /*
                         * Do we support clustering and is the support enabled
                         */
                        if (!adapter->ha) {
                                scp->result = (DID_BAD_TARGET << 16);
                                return NULL;
                        }

                        /*
                         * Allocate a SCB and initialize mailbox
                         */
                        if (!(scb = megaraid_alloc_scb(adapter, scp))) {
                                scp->result = (DID_ERROR << 16);
                                *busy = 1;
                                return NULL;
                        }

                        ccb                        = (mbox_ccb_t *)scb->ccb;
                        scb->dev_channel        = 0xFF;
                        scb->dev_target                = target;
                        ccb->raw_mbox[0]        = CLUSTER_CMD;
                        ccb->raw_mbox[2]        =  (scp->cmnd[0] == RESERVE) ?
                                                RESERVE_LD : RELEASE_LD;

                        ccb->raw_mbox[3]        = target;
                        scb->dma_direction        = scp->sc_data_direction;

                        return scb;

                default:
                        scp->result = (DID_BAD_TARGET << 16);
                        return NULL;
                }
        }
        else { // Passthru device commands

                // Do not allow access to target id > 15 or LUN > 7
                if (target > 15 || SCP2LUN(scp) > 7) {
                        scp->result = (DID_BAD_TARGET << 16);
                        return NULL;
                }

                // if fast load option was set and scan for last device is
                // over, reset the fast_load flag so that during a possible
                // next scan, devices can be made available
                if (rdev->fast_load && (target == 15) &&
                        (SCP2CHANNEL(scp) == adapter->max_channel -1)) {

                        con_log(CL_ANN, (KERN_INFO
                        "megaraid[%d]: physical device scan re-enabled\n",
                                adapter->host->host_no));
                        rdev->fast_load = 0;
                }

                /*
                 * Display the channel scan for physical devices
                 */
                if (!(rdev->last_disp & (1L << SCP2CHANNEL(scp)))) {

                        ss = rdev->fast_load ? skip : scan;

                        con_log(CL_ANN, (KERN_INFO
                                "scsi[%d]: %s scsi channel %d [Phy %d]",
                                adapter->host->host_no, ss, SCP2CHANNEL(scp),
                                channel));

                        con_log(CL_ANN, (
                                " for non-raid devices\n"));

                        rdev->last_disp |= (1L << SCP2CHANNEL(scp));
                }

                // disable channel sweep if fast load option given
                if (rdev->fast_load) {
                        scp->result = (DID_BAD_TARGET << 16);
                        return NULL;
                }

                // Allocate a SCB and initialize passthru
                if (!(scb = megaraid_alloc_scb(adapter, scp))) {
                        scp->result = (DID_ERROR << 16);
                        *busy = 1;
                        return NULL;
                }

                ccb                        = (mbox_ccb_t *)scb->ccb;
                scb->dev_channel        = channel;
                scb->dev_target                = target;
                scb->dma_direction        = scp->sc_data_direction;
                mbox                        = ccb->mbox;
                mbox64                        = ccb->mbox64;

                // Does this firmware support extended CDBs
                if (adapter->max_cdb_sz == 16) {
                        mbox->cmd                = MBOXCMD_EXTPTHRU;

                        megaraid_mbox_prepare_epthru(adapter, scb, scp);

                        mbox64->xferaddr_lo        = (uint32_t)ccb->epthru_dma_h;
                        mbox64->xferaddr_hi        = 0;
                        mbox->xferaddr                = 0xFFFFFFFF;
                }
                else {
                        mbox->cmd = MBOXCMD_PASSTHRU64;

                        megaraid_mbox_prepare_pthru(adapter, scb, scp);

                        mbox64->xferaddr_lo        = (uint32_t)ccb->pthru_dma_h;
                        mbox64->xferaddr_hi        = 0;
                        mbox->xferaddr                = 0xFFFFFFFF;
                }
                return scb;
        }

        // NOT REACHED
}


/**
 * megaraid_mbox_runpendq - execute commands queued in the pending queue
 * @adapter        : controller's soft state
 * @scb_q        : SCB to be queued in the pending list
 *
 * Scan the pending list for commands which are not yet issued and try to
 * post to the controller. The SCB can be a null pointer, which would indicate
 * no SCB to be queue, just try to execute the ones in the pending list.
 *
 * NOTE: We do not actually traverse the pending list. The SCBs are plucked
 * out from the head of the pending list. If it is successfully issued, the
 * next SCB is at the head now.
 */
static void
megaraid_mbox_runpendq(adapter_t *adapter, scb_t *scb_q)
{
        scb_t                        *scb;
        unsigned long                flags;

        spin_lock_irqsave(PENDING_LIST_LOCK(adapter), flags);

        if (scb_q) {
                scb_q->state = SCB_PENDQ;
                list_add_tail(&scb_q->list, &adapter->pend_list);
        }

        // if the adapter in not in quiescent mode, post the commands to FW
        if (adapter->quiescent) {
                spin_unlock_irqrestore(PENDING_LIST_LOCK(adapter), flags);
                return;
        }

        while (!list_empty(&adapter->pend_list)) {

                assert_spin_locked(PENDING_LIST_LOCK(adapter));

                scb = list_entry(adapter->pend_list.next, scb_t, list);

                // remove the scb from the pending list and try to
                // issue. If we are unable to issue it, put back in
                // the pending list and return

                list_del_init(&scb->list);

                spin_unlock_irqrestore(PENDING_LIST_LOCK(adapter), flags);

                // if mailbox was busy, return SCB back to pending
                // list. Make sure to add at the head, since that's
                // where it would have been removed from

                scb->state = SCB_ISSUED;

                if (mbox_post_cmd(adapter, scb) != 0) {

                        spin_lock_irqsave(PENDING_LIST_LOCK(adapter), flags);

                        scb->state = SCB_PENDQ;

                        list_add(&scb->list, &adapter->pend_list);

                        spin_unlock_irqrestore(PENDING_LIST_LOCK(adapter),
                                flags);

                        return;
                }

                spin_lock_irqsave(PENDING_LIST_LOCK(adapter), flags);
        }

        spin_unlock_irqrestore(PENDING_LIST_LOCK(adapter), flags);


        return;
}


/**
 * megaraid_mbox_prepare_pthru - prepare a command for physical devices
 * @adapter        : pointer to controller's soft state
 * @scb                : scsi control block
 * @scp                : scsi command from the mid-layer
 *
 * Prepare a command for the scsi physical devices.
 */
static void
megaraid_mbox_prepare_pthru(adapter_t *adapter, scb_t *scb,
                struct scsi_cmnd *scp)
{
        mbox_ccb_t                *ccb;
        mraid_passthru_t        *pthru;
        uint8_t                        channel;
        uint8_t                        target;

        ccb        = (mbox_ccb_t *)scb->ccb;
        pthru        = ccb->pthru;
        channel        = scb->dev_channel;
        target        = scb->dev_target;

        // 0=6sec, 1=60sec, 2=10min, 3=3hrs, 4=NO timeout
        pthru->timeout                = 4;        
        pthru->ars                = 1;
        pthru->islogical        = 0;
        pthru->channel                = 0;
        pthru->target                = (channel << 4) | target;
        pthru->logdrv                = SCP2LUN(scp);
        pthru->reqsenselen        = 14;
        pthru->cdblen                = scp->cmd_len;

        memcpy(pthru->cdb, scp->cmnd, scp->cmd_len);

        if (scsi_bufflen(scp)) {
                pthru->dataxferlen        = scsi_bufflen(scp);
                pthru->dataxferaddr        = ccb->sgl_dma_h;
                pthru->numsge                = megaraid_mbox_mksgl(adapter, scb);
        }
        else {
                pthru->dataxferaddr        = 0;
                pthru->dataxferlen        = 0;
                pthru->numsge                = 0;
        }
        return;
}


/**
 * megaraid_mbox_prepare_epthru - prepare a command for physical devices
 * @adapter        : pointer to controller's soft state
 * @scb                : scsi control block
 * @scp                : scsi command from the mid-layer
 *
 * Prepare a command for the scsi physical devices. This rountine prepares
 * commands for devices which can take extended CDBs (>10 bytes).
 */
static void
megaraid_mbox_prepare_epthru(adapter_t *adapter, scb_t *scb,
                struct scsi_cmnd *scp)
{
        mbox_ccb_t                *ccb;
        mraid_epassthru_t        *epthru;
        uint8_t                        channel;
        uint8_t                        target;

        ccb        = (mbox_ccb_t *)scb->ccb;
        epthru        = ccb->epthru;
        channel        = scb->dev_channel;
        target        = scb->dev_target;

        // 0=6sec, 1=60sec, 2=10min, 3=3hrs, 4=NO timeout
        epthru->timeout                = 4;        
        epthru->ars                = 1;
        epthru->islogical        = 0;
        epthru->channel                = 0;
        epthru->target                = (channel << 4) | target;
        epthru->logdrv                = SCP2LUN(scp);
        epthru->reqsenselen        = 14;
        epthru->cdblen                = scp->cmd_len;

        memcpy(epthru->cdb, scp->cmnd, scp->cmd_len);

        if (scsi_bufflen(scp)) {
                epthru->dataxferlen        = scsi_bufflen(scp);
                epthru->dataxferaddr        = ccb->sgl_dma_h;
                epthru->numsge                = megaraid_mbox_mksgl(adapter, scb);
        }
        else {
                epthru->dataxferaddr        = 0;
                epthru->dataxferlen        = 0;
                epthru->numsge                = 0;
        }
        return;
}


/**
 * megaraid_ack_sequence - interrupt ack sequence for memory mapped HBAs
 * @adapter        : controller's soft state
 *
 * Interrupt acknowledgement sequence for memory mapped HBAs. Find out the
 * completed command and put them on the completed list for later processing.
 *
 * Returns:        1 if the interrupt is valid, 0 otherwise
 */
static int
megaraid_ack_sequence(adapter_t *adapter)
{
        mraid_device_t                *raid_dev = ADAP2RAIDDEV(adapter);
        mbox_t                        *mbox;
        scb_t                        *scb;
        uint8_t                        nstatus;
        uint8_t                        completed[MBOX_MAX_FIRMWARE_STATUS];
        struct list_head        clist;
        int                        handled;
        uint32_t                dword;
        unsigned long                flags;
        int                        i, j;


        mbox        = raid_dev->mbox;

        // move the SCBs from the firmware completed array to our local list
        INIT_LIST_HEAD(&clist);

        // loop till F/W has more commands for us to complete
        handled = 0;
        spin_lock_irqsave(MAILBOX_LOCK(raid_dev), flags);
        do {
                /*
                 * Check if a valid interrupt is pending. If found, force the
                 * interrupt line low.
                 */
                dword = RDOUTDOOR(raid_dev);
                if (dword != 0x10001234) break;

                handled = 1;

                WROUTDOOR(raid_dev, 0x10001234);

                nstatus = 0;
                // wait for valid numstatus to post
                for (i = 0; i < 0xFFFFF; i++) {
                        if (mbox->numstatus != 0xFF) {
                                nstatus = mbox->numstatus;
                                break;
                        }
                        rmb();
                }
                mbox->numstatus = 0xFF;

                adapter->outstanding_cmds -= nstatus;

                for (i = 0; i < nstatus; i++) {

                        // wait for valid command index to post
                        for (j = 0; j < 0xFFFFF; j++) {
                                if (mbox->completed[i] != 0xFF) break;
                                rmb();
                        }
                        completed[i]                = mbox->completed[i];
                        mbox->completed[i]        = 0xFF;

                        if (completed[i] == 0xFF) {
                                con_log(CL_ANN, (KERN_CRIT
                                "megaraid: command posting timed out\n"));

                                BUG();
                                continue;
                        }

                        // Get SCB associated with this command id
                        if (completed[i] >= MBOX_MAX_SCSI_CMDS) {
                                // a cmm command
                                scb = adapter->uscb_list + (completed[i] -
                                                MBOX_MAX_SCSI_CMDS);
                        }
                        else {
                                // an os command
                                scb = adapter->kscb_list + completed[i];
                        }

                        scb->status = mbox->status;
                        list_add_tail(&scb->list, &clist);
                }

                // Acknowledge interrupt
                WRINDOOR(raid_dev, 0x02);

        } while(1);

        spin_unlock_irqrestore(MAILBOX_LOCK(raid_dev), flags);


        // put the completed commands in the completed list. DPC would
        // complete these commands later
        spin_lock_irqsave(COMPLETED_LIST_LOCK(adapter), flags);

        list_splice(&clist, &adapter->completed_list);

        spin_unlock_irqrestore(COMPLETED_LIST_LOCK(adapter), flags);


        // schedule the DPC if there is some work for it
        if (handled)
                tasklet_schedule(&adapter->dpc_h);

        return handled;
}


/**
 * megaraid_isr - isr for memory based mailbox based controllers
 * @irq                : irq
 * @devp        : pointer to our soft state
 *
 * Interrupt service routine for memory-mapped mailbox controllers.
 */
static irqreturn_t
megaraid_isr(int irq, void *devp)
{
        adapter_t        *adapter = devp;
        int                handled;

        handled = megaraid_ack_sequence(adapter);

        /* Loop through any pending requests */
        if (!adapter->quiescent) {
                megaraid_mbox_runpendq(adapter, NULL);
        }

        return IRQ_RETVAL(handled);
}


/**
 * megaraid_mbox_sync_scb - sync kernel buffers
 * @adapter        : controller's soft state
 * @scb                : pointer to the resource packet
 *
 * DMA sync if required.
 */
static void
megaraid_mbox_sync_scb(adapter_t *adapter, scb_t *scb)
{
        mbox_ccb_t        *ccb;

        ccb        = (mbox_ccb_t *)scb->ccb;

        if (scb->dma_direction == PCI_DMA_FROMDEVICE)
                pci_dma_sync_sg_for_cpu(adapter->pdev,
                                        scsi_sglist(scb->scp),
                                        scsi_sg_count(scb->scp),
                                        PCI_DMA_FROMDEVICE);

        scsi_dma_unmap(scb->scp);
        return;
}


/**
 * megaraid_mbox_dpc - the tasklet to complete the commands from completed list
 * @devp        : pointer to HBA soft state
 *
 * Pick up the commands from the completed list and send back to the owners.
 * This is a reentrant function and does not assume any locks are held while
 * it is being called.
 */
static void
megaraid_mbox_dpc(unsigned long devp)
{
        adapter_t                *adapter = (adapter_t *)devp;
        mraid_device_t                *raid_dev;
        struct list_head        clist;
        struct scatterlist        *sgl;
        scb_t                        *scb;
        scb_t                        *tmp;
        struct scsi_cmnd        *scp;
        mraid_passthru_t        *pthru;
        mraid_epassthru_t        *epthru;
        mbox_ccb_t                *ccb;
        int                        islogical;
        int                        pdev_index;
        int                        pdev_state;
        mbox_t                        *mbox;
        unsigned long                flags;
        uint8_t                        c;
        int                        status;
        uioc_t                        *kioc;


        if (!adapter) return;

        raid_dev = ADAP2RAIDDEV(adapter);

        // move the SCBs from the completed list to our local list
        INIT_LIST_HEAD(&clist);

        spin_lock_irqsave(COMPLETED_LIST_LOCK(adapter), flags);

        list_splice_init(&adapter->completed_list, &clist);

        spin_unlock_irqrestore(COMPLETED_LIST_LOCK(adapter), flags);


        list_for_each_entry_safe(scb, tmp, &clist, list) {

                status                = scb->status;
                scp                = scb->scp;
                ccb                = (mbox_ccb_t *)scb->ccb;
                pthru                = ccb->pthru;
                epthru                = ccb->epthru;
                mbox                = ccb->mbox;

                // Make sure f/w has completed a valid command
                if (scb->state != SCB_ISSUED) {
                        con_log(CL_ANN, (KERN_CRIT
                        "megaraid critical err: invalid command %d:%d:%p\n",
                                scb->sno, scb->state, scp));
                        BUG();
                        continue;        // Must never happen!
                }

                // check for the management command and complete it right away
                if (scb->sno >= MBOX_MAX_SCSI_CMDS) {
                        scb->state        = SCB_FREE;
                        scb->status        = status;

                        // remove from local clist
                        list_del_init(&scb->list);

                        kioc                        = (uioc_t *)scb->gp;
                        kioc->status                = 0;

                        megaraid_mbox_mm_done(adapter, scb);

                        continue;
                }

                // Was an abort issued for this command earlier
                if (scb->state & SCB_ABORT) {
                        con_log(CL_ANN, (KERN_NOTICE
                        "megaraid: aborted cmd %lx[%x] completed\n",
                                scp->serial_number, scb->sno));
                }

                /*
                 * If the inquiry came of a disk drive which is not part of
                 * any RAID array, expose it to the kernel. For this to be
                 * enabled, user must set the "megaraid_expose_unconf_disks"
                 * flag to 1 by specifying it on module parameter list.
                 * This would enable data migration off drives from other
                 * configurations.
                 */
                islogical = MRAID_IS_LOGICAL(adapter, scp);
                if (scp->cmnd[0] == INQUIRY && status == 0 && islogical == 0
                                && IS_RAID_CH(raid_dev, scb->dev_channel)) {

                        sgl = scsi_sglist(scp);
                        if (sg_page(sgl)) {
                                c = *(unsigned char *) sg_virt(&sgl[0]);
                        } else {
                                con_log(CL_ANN, (KERN_WARNING
                                                 "megaraid mailbox: invalid sg:%d\n",
                                                 __LINE__));
                                c = 0;
                        }

                        if ((c & 0x1F ) == TYPE_DISK) {
                                pdev_index = (scb->dev_channel * 16) +
                                        scb->dev_target;
                                pdev_state =
                                        raid_dev->pdrv_state[pdev_index] & 0x0F;

                                if (pdev_state == PDRV_ONLINE                ||
                                        pdev_state == PDRV_FAILED        ||
                                        pdev_state == PDRV_RBLD                ||
                                        pdev_state == PDRV_HOTSPARE        ||
                                        megaraid_expose_unconf_disks == 0) {

                                        status = 0xF0;
                                }
                        }
                }

                // Convert MegaRAID status to Linux error code
                switch (status) {

                case 0x00:

                        scp->result = (DID_OK << 16);
                        break;

                case 0x02:

                        /* set sense_buffer and result fields */
                        if (mbox->cmd == MBOXCMD_PASSTHRU ||
                                mbox->cmd == MBOXCMD_PASSTHRU64) {

                                memcpy(scp->sense_buffer, pthru->reqsensearea,
                                                14);

                                scp->result = DRIVER_SENSE << 24 |
                                        DID_OK << 16 | CHECK_CONDITION << 1;
                        }
                        else {
                                if (mbox->cmd == MBOXCMD_EXTPTHRU) {

                                        memcpy(scp->sense_buffer,
                                                epthru->reqsensearea, 14);

                                        scp->result = DRIVER_SENSE << 24 |
                                                DID_OK << 16 |
                                                CHECK_CONDITION << 1;
                                } else {
                                        scp->sense_buffer[0] = 0x70;
                                        scp->sense_buffer[2] = ABORTED_COMMAND;
                                        scp->result = CHECK_CONDITION << 1;
                                }
                        }
                        break;

                case 0x08:

                        scp->result = DID_BUS_BUSY << 16 | status;
                        break;

                default:

                        /*
                         * If TEST_UNIT_READY fails, we know RESERVATION_STATUS
                         * failed
                         */
                        if (scp->cmnd[0] == TEST_UNIT_READY) {
                                scp->result = DID_ERROR << 16 |
                                        RESERVATION_CONFLICT << 1;
                        }
                        else
                        /*
                         * Error code returned is 1 if Reserve or Release
                         * failed or the input parameter is invalid
                         */
                        if (status == 1 && (scp->cmnd[0] == RESERVE ||
                                         scp->cmnd[0] == RELEASE)) {

                                scp->result = DID_ERROR << 16 |
                                        RESERVATION_CONFLICT << 1;
                        }
                        else {
                                scp->result = DID_BAD_TARGET << 16 | status;
                        }
                }

                // print a debug message for all failed commands
                if (status) {
                        megaraid_mbox_display_scb(adapter, scb);
                }

                // Free our internal resources and call the mid-layer callback
                // routine
                megaraid_mbox_sync_scb(adapter, scb);

                // remove from local clist
                list_del_init(&scb->list);

                // put back in free list
                megaraid_dealloc_scb(adapter, scb);

                // send the scsi packet back to kernel
                scp->scsi_done(scp);
        }

        return;
}


/**
 * megaraid_abort_handler - abort the scsi command
 * @scp                : command to be aborted
 *
 * Abort a previous SCSI request. Only commands on the pending list can be
 * aborted. All the commands issued to the F/W must complete.
 **/
static int
megaraid_abort_handler(struct scsi_cmnd *scp)
{
        adapter_t                *adapter;
        mraid_device_t                *raid_dev;
        scb_t                        *scb;
        scb_t                        *tmp;
        int                        found;
        unsigned long                flags;
        int                        i;


        adapter                = SCP2ADAPTER(scp);
        raid_dev        = ADAP2RAIDDEV(adapter);

        con_log(CL_ANN, (KERN_WARNING
                "megaraid: aborting-%ld cmd=%x <c=%d t=%d l=%d>\n",
                scp->serial_number, scp->cmnd[0], SCP2CHANNEL(scp),
                SCP2TARGET(scp), SCP2LUN(scp)));

        // If FW has stopped responding, simply return failure
        if (raid_dev->hw_error) {
                con_log(CL_ANN, (KERN_NOTICE
                        "megaraid: hw error, not aborting\n"));
                return FAILED;
        }

        // There might a race here, where the command was completed by the
        // firmware and now it is on the completed list. Before we could
        // complete the command to the kernel in dpc, the abort came.
        // Find out if this is the case to avoid the race.
        scb = NULL;
        spin_lock_irqsave(COMPLETED_LIST_LOCK(adapter), flags);
        list_for_each_entry_safe(scb, tmp, &adapter->completed_list, list) {

                if (scb->scp == scp) {        // Found command

                        list_del_init(&scb->list);        // from completed list

                        con_log(CL_ANN, (KERN_WARNING
                        "megaraid: %ld:%d[%d:%d], abort from completed list\n",
                                scp->serial_number, scb->sno,
                                scb->dev_channel, scb->dev_target));

                        scp->result = (DID_ABORT << 16);
                        scp->scsi_done(scp);

                        megaraid_dealloc_scb(adapter, scb);

                        spin_unlock_irqrestore(COMPLETED_LIST_LOCK(adapter),
                                flags);

                        return SUCCESS;
                }
        }
        spin_unlock_irqrestore(COMPLETED_LIST_LOCK(adapter), flags);


        // Find out if this command is still on the pending list. If it is and
        // was never issued, abort and return success. If the command is owned
        // by the firmware, we must wait for it to complete by the FW.
        spin_lock_irqsave(PENDING_LIST_LOCK(adapter), flags);
        list_for_each_entry_safe(scb, tmp, &adapter->pend_list, list) {

                if (scb->scp == scp) {        // Found command

                        list_del_init(&scb->list);        // from pending list

                        ASSERT(!(scb->state & SCB_ISSUED));

                        con_log(CL_ANN, (KERN_WARNING
                                "megaraid abort: %ld[%d:%d], driver owner\n",
                                scp->serial_number, scb->dev_channel,
                                scb->dev_target));

                        scp->result = (DID_ABORT << 16);
                        scp->scsi_done(scp);

                        megaraid_dealloc_scb(adapter, scb);

                        spin_unlock_irqrestore(PENDING_LIST_LOCK(adapter),
                                flags);

                        return SUCCESS;
                }
        }
        spin_unlock_irqrestore(PENDING_LIST_LOCK(adapter), flags);


        // Check do we even own this command, in which case this would be
        // owned by the firmware. The only way to locate the FW scb is to
        // traverse through the list of all SCB, since driver does not
        // maintain these SCBs on any list
        found = 0;
        spin_lock_irq(&adapter->lock);
        for (i = 0; i < MBOX_MAX_SCSI_CMDS; i++) {
                scb = adapter->kscb_list + i;

                if (scb->scp == scp) {

                        found = 1;

                        if (!(scb->state & SCB_ISSUED)) {
                                con_log(CL_ANN, (KERN_WARNING
                                "megaraid abort: %ld%d[%d:%d], invalid state\n",
                                scp->serial_number, scb->sno, scb->dev_channel,
                                scb->dev_target));
                                BUG();
                        }
                        else {
                                con_log(CL_ANN, (KERN_WARNING
                                "megaraid abort: %ld:%d[%d:%d], fw owner\n",
                                scp->serial_number, scb->sno, scb->dev_channel,
                                scb->dev_target));
                        }
                }
        }
        spin_unlock_irq(&adapter->lock);

        if (!found) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid abort: scsi cmd:%ld, do now own\n",
                        scp->serial_number));

                // FIXME: Should there be a callback for this command?
                return SUCCESS;
        }

        // We cannot actually abort a command owned by firmware, return
        // failure and wait for reset. In host reset handler, we will find out
        // if the HBA is still live
        return FAILED;
}

/**
 * megaraid_reset_handler - device reset hadler for mailbox based driver
 * @scp                : reference command
 *
 * Reset handler for the mailbox based controller. First try to find out if
 * the FW is still live, in which case the outstanding commands counter mut go
 * down to 0. If that happens, also issue the reservation reset command to
 * relinquish (possible) reservations on the logical drives connected to this
 * host.
 **/
static int
megaraid_reset_handler(struct scsi_cmnd *scp)
{
        adapter_t        *adapter;
        scb_t                *scb;
        scb_t                *tmp;
        mraid_device_t        *raid_dev;
        unsigned long        flags;
        uint8_t                raw_mbox[sizeof(mbox_t)];
        int                rval;
        int                recovery_window;
        int                recovering;
        int                i;
        uioc_t                *kioc;

        adapter                = SCP2ADAPTER(scp);
        raid_dev        = ADAP2RAIDDEV(adapter);

        // return failure if adapter is not responding
        if (raid_dev->hw_error) {
                con_log(CL_ANN, (KERN_NOTICE
                        "megaraid: hw error, cannot reset\n"));
                return FAILED;
        }


        // Under exceptional conditions, FW can take up to 3 minutes to
        // complete command processing. Wait for additional 2 minutes for the
        // pending commands counter to go down to 0. If it doesn't, let the
        // controller be marked offline
        // Also, reset all the commands currently owned by the driver
        spin_lock_irqsave(PENDING_LIST_LOCK(adapter), flags);
        list_for_each_entry_safe(scb, tmp, &adapter->pend_list, list) {
                list_del_init(&scb->list);        // from pending list

                if (scb->sno >= MBOX_MAX_SCSI_CMDS) {
                        con_log(CL_ANN, (KERN_WARNING
                        "megaraid: IOCTL packet with %d[%d:%d] being reset\n",
                        scb->sno, scb->dev_channel, scb->dev_target));

                        scb->status = -1;

                        kioc                        = (uioc_t *)scb->gp;
                        kioc->status                = -EFAULT;

                        megaraid_mbox_mm_done(adapter, scb);
                } else {
                        if (scb->scp == scp) {        // Found command
                                con_log(CL_ANN, (KERN_WARNING
                                        "megaraid: %ld:%d[%d:%d], reset from pending list\n",
                                        scp->serial_number, scb->sno,
                                        scb->dev_channel, scb->dev_target));
                        } else {
                                con_log(CL_ANN, (KERN_WARNING
                                "megaraid: IO packet with %d[%d:%d] being reset\n",
                                scb->sno, scb->dev_channel, scb->dev_target));
                        }

                        scb->scp->result = (DID_RESET << 16);
                        scb->scp->scsi_done(scb->scp);

                        megaraid_dealloc_scb(adapter, scb);
                }
        }
        spin_unlock_irqrestore(PENDING_LIST_LOCK(adapter), flags);

        if (adapter->outstanding_cmds) {
                con_log(CL_ANN, (KERN_NOTICE
                        "megaraid: %d outstanding commands. Max wait %d sec\n",
                        adapter->outstanding_cmds,
                        (MBOX_RESET_WAIT + MBOX_RESET_EXT_WAIT)));
        }

        recovery_window = MBOX_RESET_WAIT + MBOX_RESET_EXT_WAIT;

        recovering = adapter->outstanding_cmds;

        for (i = 0; i < recovery_window; i++) {

                megaraid_ack_sequence(adapter);

                // print a message once every 5 seconds only
                if (!(i % 5)) {
                        con_log(CL_ANN, (
                        "megaraid mbox: Wait for %d commands to complete:%d\n",
                                adapter->outstanding_cmds,
                                (MBOX_RESET_WAIT + MBOX_RESET_EXT_WAIT) - i));
                }

                // bailout if no recovery happended in reset time
                if (adapter->outstanding_cmds == 0) {
                        break;
                }

                msleep(1000);
        }

        spin_lock(&adapter->lock);

        // If still outstanding commands, bail out
        if (adapter->outstanding_cmds) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid mbox: critical hardware error!\n"));

                raid_dev->hw_error = 1;

                rval = FAILED;
                goto out;
        }
        else {
                con_log(CL_ANN, (KERN_NOTICE
                "megaraid mbox: reset sequence completed sucessfully\n"));
        }


        // If the controller supports clustering, reset reservations
        if (!adapter->ha) {
                rval = SUCCESS;
                goto out;
        }

        // clear reservations if any
        raw_mbox[0] = CLUSTER_CMD;
        raw_mbox[2] = RESET_RESERVATIONS;

        rval = SUCCESS;
        if (mbox_post_sync_cmd_fast(adapter, raw_mbox) == 0) {
                con_log(CL_ANN,
                        (KERN_INFO "megaraid: reservation reset\n"));
        }
        else {
                rval = FAILED;
                con_log(CL_ANN, (KERN_WARNING
                                "megaraid: reservation reset failed\n"));
        }

 out:
        spin_unlock_irq(&adapter->lock);
        return rval;
}

/*
 * START: internal commands library
 *
 * This section of the driver has the common routine used by the driver and
 * also has all the FW routines
 */

/**
 * mbox_post_sync_cmd() - blocking command to the mailbox based controllers
 * @adapter        : controller's soft state
 * @raw_mbox        : the mailbox
 *
 * Issue a scb in synchronous and non-interrupt mode for mailbox based
 * controllers.
 */
static int
mbox_post_sync_cmd(adapter_t *adapter, uint8_t raw_mbox[])
{
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        mbox64_t        *mbox64;
        mbox_t                *mbox;
        uint8_t                status;
        int                i;


        mbox64        = raid_dev->mbox64;
        mbox        = raid_dev->mbox;

        /*
         * Wait until mailbox is free
         */
        if (megaraid_busywait_mbox(raid_dev) != 0)
                goto blocked_mailbox;

        /*
         * Copy mailbox data into host structure
         */
        memcpy((caddr_t)mbox, (caddr_t)raw_mbox, 16);
        mbox->cmdid                = 0xFE;
        mbox->busy                = 1;
        mbox->poll                = 0;
        mbox->ack                = 0;
        mbox->numstatus                = 0xFF;
        mbox->status                = 0xFF;

        wmb();
        WRINDOOR(raid_dev, raid_dev->mbox_dma | 0x1);

        // wait for maximum 1 second for status to post. If the status is not
        // available within 1 second, assume FW is initializing and wait
        // for an extended amount of time
        if (mbox->numstatus == 0xFF) {        // status not yet available
                udelay(25);

                for (i = 0; mbox->numstatus == 0xFF && i < 1000; i++) {
                        rmb();
                        msleep(1);
                }


                if (i == 1000) {
                        con_log(CL_ANN, (KERN_NOTICE
                                "megaraid mailbox: wait for FW to boot      "));

                        for (i = 0; (mbox->numstatus == 0xFF) &&
                                        (i < MBOX_RESET_WAIT); i++) {
                                rmb();
                                con_log(CL_ANN, ("\b\b\b\b\b[%03d]",
                                                        MBOX_RESET_WAIT - i));
                                msleep(1000);
                        }

                        if (i == MBOX_RESET_WAIT) {

                                con_log(CL_ANN, (
                                "\nmegaraid mailbox: status not available\n"));

                                return -1;
                        }
                        con_log(CL_ANN, ("\b\b\b\b\b[ok] \n"));
                }
        }

        // wait for maximum 1 second for poll semaphore
        if (mbox->poll != 0x77) {
                udelay(25);

                for (i = 0; (mbox->poll != 0x77) && (i < 1000); i++) {
                        rmb();
                        msleep(1);
                }

                if (i == 1000) {
                        con_log(CL_ANN, (KERN_WARNING
                        "megaraid mailbox: could not get poll semaphore\n"));
                        return -1;
                }
        }

        WRINDOOR(raid_dev, raid_dev->mbox_dma | 0x2);
        wmb();

        // wait for maximum 1 second for acknowledgement
        if (RDINDOOR(raid_dev) & 0x2) {
                udelay(25);

                for (i = 0; (RDINDOOR(raid_dev) & 0x2) && (i < 1000); i++) {
                        rmb();
                        msleep(1);
                }

                if (i == 1000) {
                        con_log(CL_ANN, (KERN_WARNING
                                "megaraid mailbox: could not acknowledge\n"));
                        return -1;
                }
        }
        mbox->poll        = 0;
        mbox->ack        = 0x77;

        status = mbox->status;

        // invalidate the completed command id array. After command
        // completion, firmware would write the valid id.
        mbox->numstatus        = 0xFF;
        mbox->status        = 0xFF;
        for (i = 0; i < MBOX_MAX_FIRMWARE_STATUS; i++) {
                mbox->completed[i] = 0xFF;
        }

        return status;

blocked_mailbox:

        con_log(CL_ANN, (KERN_WARNING "megaraid: blocked mailbox\n") );
        return -1;
}


/**
 * mbox_post_sync_cmd_fast - blocking command to the mailbox based controllers
 * @adapter        : controller's soft state
 * @raw_mbox        : the mailbox
 *
 * Issue a scb in synchronous and non-interrupt mode for mailbox based
 * controllers. This is a faster version of the synchronous command and
 * therefore can be called in interrupt-context as well.
 */
static int
mbox_post_sync_cmd_fast(adapter_t *adapter, uint8_t raw_mbox[])
{
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        mbox_t                *mbox;
        long                i;


        mbox        = raid_dev->mbox;

        // return immediately if the mailbox is busy
        if (mbox->busy) return -1;

        // Copy mailbox data into host structure
        memcpy((caddr_t)mbox, (caddr_t)raw_mbox, 14);
        mbox->cmdid                = 0xFE;
        mbox->busy                = 1;
        mbox->poll                = 0;
        mbox->ack                = 0;
        mbox->numstatus                = 0xFF;
        mbox->status                = 0xFF;

        wmb();
        WRINDOOR(raid_dev, raid_dev->mbox_dma | 0x1);

        for (i = 0; i < MBOX_SYNC_WAIT_CNT; i++) {
                if (mbox->numstatus != 0xFF) break;
                rmb();
                udelay(MBOX_SYNC_DELAY_200);
        }

        if (i == MBOX_SYNC_WAIT_CNT) {
                // We may need to re-calibrate the counter
                con_log(CL_ANN, (KERN_CRIT
                        "megaraid: fast sync command timed out\n"));
        }

        WRINDOOR(raid_dev, raid_dev->mbox_dma | 0x2);
        wmb();

        return mbox->status;
}


/**
 * megaraid_busywait_mbox() - Wait until the controller's mailbox is available
 * @raid_dev        : RAID device (HBA) soft state
 *
 * Wait until the controller's mailbox is available to accept more commands.
 * Wait for at most 1 second.
 */
static int
megaraid_busywait_mbox(mraid_device_t *raid_dev)
{
        mbox_t        *mbox = raid_dev->mbox;
        int        i = 0;

        if (mbox->busy) {
                udelay(25);
                for (i = 0; mbox->busy && i < 1000; i++)
                        msleep(1);
        }

        if (i < 1000) return 0;
        else return -1;
}


/**
 * megaraid_mbox_product_info - some static information about the controller
 * @adapter        : our soft state
 *
 * Issue commands to the controller to grab some parameters required by our
 * caller.
 */
static int
megaraid_mbox_product_info(adapter_t *adapter)
{
        mraid_device_t                *raid_dev = ADAP2RAIDDEV(adapter);
        mbox_t                        *mbox;
        uint8_t                        raw_mbox[sizeof(mbox_t)];
        mraid_pinfo_t                *pinfo;
        dma_addr_t                pinfo_dma_h;
        mraid_inquiry3_t        *mraid_inq3;
        int                        i;


        memset((caddr_t)raw_mbox, 0, sizeof(raw_mbox));
        mbox = (mbox_t *)raw_mbox;

        /*
         * Issue an ENQUIRY3 command to find out certain adapter parameters,
         * e.g., max channels, max commands etc.
         */
        pinfo = pci_alloc_consistent(adapter->pdev, sizeof(mraid_pinfo_t),
                        &pinfo_dma_h);

        if (pinfo == NULL) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));

                return -1;
        }
        memset(pinfo, 0, sizeof(mraid_pinfo_t));

        mbox->xferaddr = (uint32_t)adapter->ibuf_dma_h;
        memset((void *)adapter->ibuf, 0, MBOX_IBUF_SIZE);

        raw_mbox[0] = FC_NEW_CONFIG;
        raw_mbox[2] = NC_SUBOP_ENQUIRY3;
        raw_mbox[3] = ENQ3_GET_SOLICITED_FULL;

        // Issue the command
        if (mbox_post_sync_cmd(adapter, raw_mbox) != 0) {

                con_log(CL_ANN, (KERN_WARNING "megaraid: Inquiry3 failed\n"));

                pci_free_consistent(adapter->pdev, sizeof(mraid_pinfo_t),
                        pinfo, pinfo_dma_h);

                return -1;
        }

        /*
         * Collect information about state of each physical drive
         * attached to the controller. We will expose all the disks
         * which are not part of RAID
         */
        mraid_inq3 = (mraid_inquiry3_t *)adapter->ibuf;
        for (i = 0; i < MBOX_MAX_PHYSICAL_DRIVES; i++) {
                raid_dev->pdrv_state[i] = mraid_inq3->pdrv_state[i];
        }

        /*
         * Get product info for information like number of channels,
         * maximum commands supported.
         */
        memset((caddr_t)raw_mbox, 0, sizeof(raw_mbox));
        mbox->xferaddr = (uint32_t)pinfo_dma_h;

        raw_mbox[0] = FC_NEW_CONFIG;
        raw_mbox[2] = NC_SUBOP_PRODUCT_INFO;

        if (mbox_post_sync_cmd(adapter, raw_mbox) != 0) {

                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: product info failed\n"));

                pci_free_consistent(adapter->pdev, sizeof(mraid_pinfo_t),
                        pinfo, pinfo_dma_h);

                return -1;
        }

        /*
         * Setup some parameters for host, as required by our caller
         */
        adapter->max_channel = pinfo->nchannels;

        /*
         * we will export all the logical drives on a single channel.
         * Add 1 since inquires do not come for inititor ID
         */
        adapter->max_target        = MAX_LOGICAL_DRIVES_40LD + 1;
        adapter->max_lun        = 8;        // up to 8 LUNs for non-disk devices

        /*
         * These are the maximum outstanding commands for the scsi-layer
         */
        adapter->max_cmds        = MBOX_MAX_SCSI_CMDS;

        memset(adapter->fw_version, 0, VERSION_SIZE);
        memset(adapter->bios_version, 0, VERSION_SIZE);

        memcpy(adapter->fw_version, pinfo->fw_version, 4);
        adapter->fw_version[4] = 0;

        memcpy(adapter->bios_version, pinfo->bios_version, 4);
        adapter->bios_version[4] = 0;

        con_log(CL_ANN, (KERN_NOTICE
                "megaraid: fw version:[%s] bios version:[%s]\n",
                adapter->fw_version, adapter->bios_version));

        pci_free_consistent(adapter->pdev, sizeof(mraid_pinfo_t), pinfo,
                        pinfo_dma_h);

        return 0;
}



/**
 * megaraid_mbox_extended_cdb - check for support for extended CDBs
 * @adapter        : soft state for the controller
 *
 * This routine check whether the controller in question supports extended
 * ( > 10 bytes ) CDBs.
 */
static int
megaraid_mbox_extended_cdb(adapter_t *adapter)
{
        mbox_t                *mbox;
        uint8_t                raw_mbox[sizeof(mbox_t)];
        int                rval;

        mbox = (mbox_t *)raw_mbox;

        memset((caddr_t)raw_mbox, 0, sizeof(raw_mbox));
        mbox->xferaddr        = (uint32_t)adapter->ibuf_dma_h;

        memset((void *)adapter->ibuf, 0, MBOX_IBUF_SIZE);

        raw_mbox[0] = MAIN_MISC_OPCODE;
        raw_mbox[2] = SUPPORT_EXT_CDB;

        /*
         * Issue the command
         */
        rval = 0;
        if (mbox_post_sync_cmd(adapter, raw_mbox) != 0) {
                rval = -1;
        }

        return rval;
}


/**
 * megaraid_mbox_support_ha - Do we support clustering
 * @adapter        : soft state for the controller
 * @init_id        : ID of the initiator
 *
 * Determine if the firmware supports clustering and the ID of the initiator.
 */
static int
megaraid_mbox_support_ha(adapter_t *adapter, uint16_t *init_id)
{
        mbox_t                *mbox;
        uint8_t                raw_mbox[sizeof(mbox_t)];
        int                rval;


        mbox = (mbox_t *)raw_mbox;

        memset((caddr_t)raw_mbox, 0, sizeof(raw_mbox));

        mbox->xferaddr = (uint32_t)adapter->ibuf_dma_h;

        memset((void *)adapter->ibuf, 0, MBOX_IBUF_SIZE);

        raw_mbox[0] = GET_TARGET_ID;

        // Issue the command
        *init_id = 7;
        rval =  -1;
        if (mbox_post_sync_cmd(adapter, raw_mbox) == 0) {

                *init_id = *(uint8_t *)adapter->ibuf;

                con_log(CL_ANN, (KERN_INFO
                        "megaraid: cluster firmware, initiator ID: %d\n",
                        *init_id));

                rval =  0;
        }

        return rval;
}


/**
 * megaraid_mbox_support_random_del - Do we support random deletion
 * @adapter        : soft state for the controller
 *
 * Determine if the firmware supports random deletion.
 * Return:        1 is operation supported, 0 otherwise
 */
static int
megaraid_mbox_support_random_del(adapter_t *adapter)
{
        mbox_t                *mbox;
        uint8_t                raw_mbox[sizeof(mbox_t)];
        int                rval;

        /*
         * Newer firmware on Dell CERC expect a different
         * random deletion handling, so disable it.
         */
        if (adapter->pdev->vendor == PCI_VENDOR_ID_AMI &&
            adapter->pdev->device == PCI_DEVICE_ID_AMI_MEGARAID3 &&
            adapter->pdev->subsystem_vendor == PCI_VENDOR_ID_DELL &&
            adapter->pdev->subsystem_device == PCI_SUBSYS_ID_CERC_ATA100_4CH &&
            (adapter->fw_version[0] > '6' ||
             (adapter->fw_version[0] == '6' &&
              adapter->fw_version[2] > '6') ||
             (adapter->fw_version[0] == '6'
              && adapter->fw_version[2] == '6'
              && adapter->fw_version[3] > '1'))) {
                con_log(CL_DLEVEL1, ("megaraid: disable random deletion\n"));
                return 0;
        }

        mbox = (mbox_t *)raw_mbox;

        memset((caddr_t)raw_mbox, 0, sizeof(mbox_t));

        raw_mbox[0] = FC_DEL_LOGDRV;
        raw_mbox[2] = OP_SUP_DEL_LOGDRV;

        // Issue the command
        rval = 0;
        if (mbox_post_sync_cmd(adapter, raw_mbox) == 0) {

                con_log(CL_DLEVEL1, ("megaraid: supports random deletion\n"));

                rval =  1;
        }

        return rval;
}


/**
 * megaraid_mbox_get_max_sg - maximum sg elements supported by the firmware
 * @adapter        : soft state for the controller
 *
 * Find out the maximum number of scatter-gather elements supported by the
 * firmware.
 */
static int
megaraid_mbox_get_max_sg(adapter_t *adapter)
{
        mbox_t                *mbox;
        uint8_t                raw_mbox[sizeof(mbox_t)];
        int                nsg;


        mbox = (mbox_t *)raw_mbox;

        memset((caddr_t)raw_mbox, 0, sizeof(mbox_t));

        mbox->xferaddr = (uint32_t)adapter->ibuf_dma_h;

        memset((void *)adapter->ibuf, 0, MBOX_IBUF_SIZE);

        raw_mbox[0] = MAIN_MISC_OPCODE;
        raw_mbox[2] = GET_MAX_SG_SUPPORT;

        // Issue the command
        if (mbox_post_sync_cmd(adapter, raw_mbox) == 0) {
                nsg =  *(uint8_t *)adapter->ibuf;
        }
        else {
                nsg =  MBOX_DEFAULT_SG_SIZE;
        }

        if (nsg > MBOX_MAX_SG_SIZE) nsg = MBOX_MAX_SG_SIZE;

        return nsg;
}


/**
 * megaraid_mbox_enum_raid_scsi - enumerate the RAID and SCSI channels
 * @adapter        : soft state for the controller
 *
 * Enumerate the RAID and SCSI channels for ROMB platforms so that channels
 * can be exported as regular SCSI channels.
 */
static void
megaraid_mbox_enum_raid_scsi(adapter_t *adapter)
{
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        mbox_t                *mbox;
        uint8_t                raw_mbox[sizeof(mbox_t)];


        mbox = (mbox_t *)raw_mbox;

        memset((caddr_t)raw_mbox, 0, sizeof(mbox_t));

        mbox->xferaddr = (uint32_t)adapter->ibuf_dma_h;

        memset((void *)adapter->ibuf, 0, MBOX_IBUF_SIZE);

        raw_mbox[0] = CHNL_CLASS;
        raw_mbox[2] = GET_CHNL_CLASS;

        // Issue the command. If the command fails, all channels are RAID
        // channels
        raid_dev->channel_class = 0xFF;
        if (mbox_post_sync_cmd(adapter, raw_mbox) == 0) {
                raid_dev->channel_class =  *(uint8_t *)adapter->ibuf;
        }

        return;
}


/**
 * megaraid_mbox_flush_cache - flush adapter and disks cache
 * @adapter                : soft state for the controller
 *
 * Flush adapter cache followed by disks cache.
 */
static void
megaraid_mbox_flush_cache(adapter_t *adapter)
{
        mbox_t        *mbox;
        uint8_t        raw_mbox[sizeof(mbox_t)];


        mbox = (mbox_t *)raw_mbox;

        memset((caddr_t)raw_mbox, 0, sizeof(mbox_t));

        raw_mbox[0] = FLUSH_ADAPTER;

        if (mbox_post_sync_cmd(adapter, raw_mbox) != 0) {
                con_log(CL_ANN, ("megaraid: flush adapter failed\n"));
        }

        raw_mbox[0] = FLUSH_SYSTEM;

        if (mbox_post_sync_cmd(adapter, raw_mbox) != 0) {
                con_log(CL_ANN, ("megaraid: flush disks cache failed\n"));
        }

        return;
}


/**
 * megaraid_mbox_fire_sync_cmd - fire the sync cmd
 * @adapter                : soft state for the controller
 *
 * Clears the pending cmds in FW and reinits its RAID structs.
 */
static int
megaraid_mbox_fire_sync_cmd(adapter_t *adapter)
{
        mbox_t        *mbox;
        uint8_t        raw_mbox[sizeof(mbox_t)];
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        mbox64_t *mbox64;
        int        status = 0;
        int i;
        uint32_t dword;

        mbox = (mbox_t *)raw_mbox;

        memset((caddr_t)raw_mbox, 0, sizeof(mbox_t));

        raw_mbox[0] = 0xFF;

        mbox64        = raid_dev->mbox64;
        mbox        = raid_dev->mbox;

        /* Wait until mailbox is free */
        if (megaraid_busywait_mbox(raid_dev) != 0) {
                status = 1;
                goto blocked_mailbox;
        }

        /* Copy mailbox data into host structure */
        memcpy((caddr_t)mbox, (caddr_t)raw_mbox, 16);
        mbox->cmdid                = 0xFE;
        mbox->busy                = 1;
        mbox->poll                = 0;
        mbox->ack                = 0;
        mbox->numstatus                = 0;
        mbox->status                = 0;

        wmb();
        WRINDOOR(raid_dev, raid_dev->mbox_dma | 0x1);

        /* Wait for maximum 1 min for status to post.
         * If the Firmware SUPPORTS the ABOVE COMMAND,
         * mbox->cmd will be set to 0
         * else
         * the firmware will reject the command with
         * mbox->numstatus set to 1
         */

        i = 0;
        status = 0;
        while (!mbox->numstatus && mbox->cmd == 0xFF) {
                rmb();
                msleep(1);
                i++;
                if (i > 1000 * 60) {
                        status = 1;
                        break;
                }
        }
        if (mbox->numstatus == 1)
                status = 1; /*cmd not supported*/

        /* Check for interrupt line */
        dword = RDOUTDOOR(raid_dev);
        WROUTDOOR(raid_dev, dword);
        WRINDOOR(raid_dev,2);

        return status;

blocked_mailbox:
        con_log(CL_ANN, (KERN_WARNING "megaraid: blocked mailbox\n"));
        return status;
}

/**
 * megaraid_mbox_display_scb - display SCB information, mostly debug purposes
 * @adapter                : controller's soft state
 * @scb                        : SCB to be displayed
 * @level                : debug level for console print
 *
 * Diplay information about the given SCB iff the current debug level is
 * verbose.
 */
static void
megaraid_mbox_display_scb(adapter_t *adapter, scb_t *scb)
{
        mbox_ccb_t                *ccb;
        struct scsi_cmnd        *scp;
        mbox_t                        *mbox;
        int                        level;
        int                        i;


        ccb        = (mbox_ccb_t *)scb->ccb;
        scp        = scb->scp;
        mbox        = ccb->mbox;

        level = CL_DLEVEL3;

        con_log(level, (KERN_NOTICE
                "megaraid mailbox: status:%#x cmd:%#x id:%#x ", scb->status,
                mbox->cmd, scb->sno));

        con_log(level, ("sec:%#x lba:%#x addr:%#x ld:%d sg:%d\n",
                mbox->numsectors, mbox->lba, mbox->xferaddr, mbox->logdrv,
                mbox->numsge));

        if (!scp) return;

        con_log(level, (KERN_NOTICE "scsi cmnd: "));

        for (i = 0; i < scp->cmd_len; i++) {
                con_log(level, ("%#2.02x ", scp->cmnd[i]));
        }

        con_log(level, ("\n"));

        return;
}


/**
 * megaraid_mbox_setup_device_map - manage device ids
 * @adapter        : Driver's soft state
 *
 * Manange the device ids to have an appropraite mapping between the kernel
 * scsi addresses and megaraid scsi and logical drive addresses. We export
 * scsi devices on their actual addresses, whereas the logical drives are
 * exported on a virtual scsi channel.
 */
static void
megaraid_mbox_setup_device_map(adapter_t *adapter)
{
        uint8_t                c;
        uint8_t                t;

        /*
         * First fill the values on the logical drive channel
         */
        for (t = 0; t < LSI_MAX_LOGICAL_DRIVES_64LD; t++)
                adapter->device_ids[adapter->max_channel][t] =
                        (t < adapter->init_id) ?  t : t - 1;

        adapter->device_ids[adapter->max_channel][adapter->init_id] = 0xFF;

        /*
         * Fill the values on the physical devices channels
         */
        for (c = 0; c < adapter->max_channel; c++)
                for (t = 0; t < LSI_MAX_LOGICAL_DRIVES_64LD; t++)
                        adapter->device_ids[c][t] = (c << 8) | t;
}


/*
 * END: internal commands library
 */

/*
 * START: Interface for the common management module
 *
 * This is the module, which interfaces with the common management module to
 * provide support for ioctl and sysfs
 */

/**
 * megaraid_cmm_register - register with the management module
 * @adapter                : HBA soft state
 *
 * Register with the management module, which allows applications to issue
 * ioctl calls to the drivers. This interface is used by the management module
 * to setup sysfs support as well.
 */
static int
megaraid_cmm_register(adapter_t *adapter)
{
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        mraid_mmadp_t        adp;
        scb_t                *scb;
        mbox_ccb_t        *ccb;
        int                rval;
        int                i;

        // Allocate memory for the base list of scb for management module.
        adapter->uscb_list = kcalloc(MBOX_MAX_USER_CMDS, sizeof(scb_t), GFP_KERNEL);

        if (adapter->uscb_list == NULL) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));
                return -1;
        }


        // Initialize the synchronization parameters for resources for
        // commands for management module
        INIT_LIST_HEAD(&adapter->uscb_pool);

        spin_lock_init(USER_FREE_LIST_LOCK(adapter));



        // link all the packets. Note, CCB for commands, coming from the
        // commom management module, mailbox physical address are already
        // setup by it. We just need placeholder for that in our local command
        // control blocks
        for (i = 0; i < MBOX_MAX_USER_CMDS; i++) {

                scb                        = adapter->uscb_list + i;
                ccb                        = raid_dev->uccb_list + i;

                scb->ccb                = (caddr_t)ccb;
                ccb->mbox64                = raid_dev->umbox64 + i;
                ccb->mbox                = &ccb->mbox64->mbox32;
                ccb->raw_mbox                = (uint8_t *)ccb->mbox;

                scb->gp                        = 0;

                // COMMAND ID 0 - (MBOX_MAX_SCSI_CMDS-1) ARE RESERVED FOR
                // COMMANDS COMING FROM IO SUBSYSTEM (MID-LAYER)
                scb->sno                = i + MBOX_MAX_SCSI_CMDS;

                scb->scp                = NULL;
                scb->state                = SCB_FREE;
                scb->dma_direction        = PCI_DMA_NONE;
                scb->dma_type                = MRAID_DMA_NONE;
                scb->dev_channel        = -1;
                scb->dev_target                = -1;

                // put scb in the free pool
                list_add_tail(&scb->list, &adapter->uscb_pool);
        }

        adp.unique_id                = adapter->unique_id;
        adp.drvr_type                = DRVRTYPE_MBOX;
        adp.drvr_data                = (unsigned long)adapter;
        adp.pdev                = adapter->pdev;
        adp.issue_uioc                = megaraid_mbox_mm_handler;
        adp.timeout                = MBOX_RESET_WAIT + MBOX_RESET_EXT_WAIT;
        adp.max_kioc                = MBOX_MAX_USER_CMDS;

        if ((rval = mraid_mm_register_adp(&adp)) != 0) {

                con_log(CL_ANN, (KERN_WARNING
                        "megaraid mbox: did not register with CMM\n"));

                kfree(adapter->uscb_list);
        }

        return rval;
}


/**
 * megaraid_cmm_unregister - un-register with the management module
 * @adapter                : HBA soft state
 *
 * Un-register with the management module.
 * FIXME: mgmt module must return failure for unregister if it has pending
 * commands in LLD.
 */
static int
megaraid_cmm_unregister(adapter_t *adapter)
{
        kfree(adapter->uscb_list);
        mraid_mm_unregister_adp(adapter->unique_id);
        return 0;
}


/**
 * megaraid_mbox_mm_handler - interface for CMM to issue commands to LLD
 * @drvr_data                : LLD specific data
 * @kioc                : CMM interface packet
 * @action                : command action
 *
 * This routine is invoked whenever the Common Management Module (CMM) has a
 * command for us. The 'action' parameter specifies if this is a new command
 * or otherwise.
 */
static int
megaraid_mbox_mm_handler(unsigned long drvr_data, uioc_t *kioc, uint32_t action)
{
        adapter_t *adapter;

        if (action != IOCTL_ISSUE) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: unsupported management action:%#2x\n",
                        action));
                return (-ENOTSUPP);
        }

        adapter = (adapter_t *)drvr_data;

        // make sure this adapter is not being detached right now.
        if (atomic_read(&adapter->being_detached)) {
                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: reject management request, detaching\n"));
                return (-ENODEV);
        }

        switch (kioc->opcode) {

        case GET_ADAP_INFO:

                kioc->status =  gather_hbainfo(adapter, (mraid_hba_info_t *)
                                        (unsigned long)kioc->buf_vaddr);

                kioc->done(kioc);

                return kioc->status;

        case MBOX_CMD:

                return megaraid_mbox_mm_command(adapter, kioc);

        default:
                kioc->status = (-EINVAL);
                kioc->done(kioc);
                return (-EINVAL);
        }

        return 0;        // not reached
}

/**
 * megaraid_mbox_mm_command - issues commands routed through CMM
 * @adapter                : HBA soft state
 * @kioc                : management command packet
 *
 * Issues commands, which are routed through the management module.
 */
static int
megaraid_mbox_mm_command(adapter_t *adapter, uioc_t *kioc)
{
        struct list_head        *head = &adapter->uscb_pool;
        mbox64_t                *mbox64;
        uint8_t                        *raw_mbox;
        scb_t                        *scb;
        mbox_ccb_t                *ccb;
        unsigned long                flags;

        // detach one scb from free pool
        spin_lock_irqsave(USER_FREE_LIST_LOCK(adapter), flags);

        if (list_empty(head)) {        // should never happen because of CMM

                con_log(CL_ANN, (KERN_WARNING
                        "megaraid mbox: bug in cmm handler, lost resources\n"));

                spin_unlock_irqrestore(USER_FREE_LIST_LOCK(adapter), flags);

                return (-EINVAL);
        }

        scb = list_entry(head->next, scb_t, list);
        list_del_init(&scb->list);

        spin_unlock_irqrestore(USER_FREE_LIST_LOCK(adapter), flags);

        scb->state                = SCB_ACTIVE;
        scb->dma_type                = MRAID_DMA_NONE;
        scb->dma_direction        = PCI_DMA_NONE;

        ccb                = (mbox_ccb_t *)scb->ccb;
        mbox64                = (mbox64_t *)(unsigned long)kioc->cmdbuf;
        raw_mbox        = (uint8_t *)&mbox64->mbox32;

        memcpy(ccb->mbox64, mbox64, sizeof(mbox64_t));

        scb->gp                = (unsigned long)kioc;

        /*
         * If it is a logdrv random delete operation, we have to wait till
         * there are no outstanding cmds at the fw and then issue it directly
         */
        if (raw_mbox[0] == FC_DEL_LOGDRV && raw_mbox[2] == OP_DEL_LOGDRV) {

                if (wait_till_fw_empty(adapter)) {
                        con_log(CL_ANN, (KERN_NOTICE
                                "megaraid mbox: LD delete, timed out\n"));

                        kioc->status = -ETIME;

                        scb->status = -1;

                        megaraid_mbox_mm_done(adapter, scb);

                        return (-ETIME);
                }

                INIT_LIST_HEAD(&scb->list);

                scb->state = SCB_ISSUED;
                if (mbox_post_cmd(adapter, scb) != 0) {

                        con_log(CL_ANN, (KERN_NOTICE
                                "megaraid mbox: LD delete, mailbox busy\n"));

                        kioc->status = -EBUSY;

                        scb->status = -1;

                        megaraid_mbox_mm_done(adapter, scb);

                        return (-EBUSY);
                }

                return 0;
        }

        // put the command on the pending list and execute
        megaraid_mbox_runpendq(adapter, scb);

        return 0;
}


static int
wait_till_fw_empty(adapter_t *adapter)
{
        unsigned long        flags = 0;
        int                i;


        /*
         * Set the quiescent flag to stop issuing cmds to FW.
         */
        spin_lock_irqsave(&adapter->lock, flags);
        adapter->quiescent++;
        spin_unlock_irqrestore(&adapter->lock, flags);

        /*
         * Wait till there are no more cmds outstanding at FW. Try for at most
         * 60 seconds
         */
        for (i = 0; i < 60 && adapter->outstanding_cmds; i++) {
                con_log(CL_DLEVEL1, (KERN_INFO
                        "megaraid: FW has %d pending commands\n",
                        adapter->outstanding_cmds));

                msleep(1000);
        }

        return adapter->outstanding_cmds;
}


/**
 * megaraid_mbox_mm_done - callback for CMM commands
 * @adapter        : HBA soft state
 * @scb                : completed command
 *
 * Callback routine for internal commands originated from the management
 * module.
 */
static void
megaraid_mbox_mm_done(adapter_t *adapter, scb_t *scb)
{
        uioc_t                        *kioc;
        mbox64_t                *mbox64;
        uint8_t                        *raw_mbox;
        unsigned long                flags;

        kioc                        = (uioc_t *)scb->gp;
        mbox64                        = (mbox64_t *)(unsigned long)kioc->cmdbuf;
        mbox64->mbox32.status        = scb->status;
        raw_mbox                = (uint8_t *)&mbox64->mbox32;


        // put scb in the free pool
        scb->state        = SCB_FREE;
        scb->scp        = NULL;

        spin_lock_irqsave(USER_FREE_LIST_LOCK(adapter), flags);

        list_add(&scb->list, &adapter->uscb_pool);

        spin_unlock_irqrestore(USER_FREE_LIST_LOCK(adapter), flags);

        // if a delete logical drive operation succeeded, restart the
        // controller
        if (raw_mbox[0] == FC_DEL_LOGDRV && raw_mbox[2] == OP_DEL_LOGDRV) {

                adapter->quiescent--;

                megaraid_mbox_runpendq(adapter, NULL);
        }

        kioc->done(kioc);

        return;
}


/**
 * gather_hbainfo - HBA characteristics for the applications
 * @adapter                : HBA soft state
 * @hinfo                : pointer to the caller's host info strucuture
 */
static int
gather_hbainfo(adapter_t *adapter, mraid_hba_info_t *hinfo)
{
        uint8_t        dmajor;

        dmajor                        = megaraid_mbox_version[0];

        hinfo->pci_vendor_id        = adapter->pdev->vendor;
        hinfo->pci_device_id        = adapter->pdev->device;
        hinfo->subsys_vendor_id        = adapter->pdev->subsystem_vendor;
        hinfo->subsys_device_id        = adapter->pdev->subsystem_device;

        hinfo->pci_bus                = adapter->pdev->bus->number;
        hinfo->pci_dev_fn        = adapter->pdev->devfn;
        hinfo->pci_slot                = PCI_SLOT(adapter->pdev->devfn);
        hinfo->irq                = adapter->host->irq;
        hinfo->baseport                = ADAP2RAIDDEV(adapter)->baseport;

        hinfo->unique_id        = (hinfo->pci_bus << 8) | adapter->pdev->devfn;
        hinfo->host_no                = adapter->host->host_no;

        return 0;
}

/*
 * END: Interface for the common management module
 */



/**
 * megaraid_sysfs_alloc_resources - allocate sysfs related resources
 * @adapter        : controller's soft state
 *
 * Allocate packets required to issue FW calls whenever the sysfs attributes
 * are read. These attributes would require up-to-date information from the
 * FW. Also set up resources for mutual exclusion to share these resources and
 * the wait queue.
 *
 * Return 0 on success.
 * Return -ERROR_CODE on failure.
 */
static int
megaraid_sysfs_alloc_resources(adapter_t *adapter)
{
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        int                rval = 0;

        raid_dev->sysfs_uioc = kmalloc(sizeof(uioc_t), GFP_KERNEL);

        raid_dev->sysfs_mbox64 = kmalloc(sizeof(mbox64_t), GFP_KERNEL);

        raid_dev->sysfs_buffer = pci_alloc_consistent(adapter->pdev,
                        PAGE_SIZE, &raid_dev->sysfs_buffer_dma);

        if (!raid_dev->sysfs_uioc || !raid_dev->sysfs_mbox64 ||
                !raid_dev->sysfs_buffer) {

                con_log(CL_ANN, (KERN_WARNING
                        "megaraid: out of memory, %s %d\n", __func__,
                        __LINE__));

                rval = -ENOMEM;

                megaraid_sysfs_free_resources(adapter);
        }

        mutex_init(&raid_dev->sysfs_mtx);

        init_waitqueue_head(&raid_dev->sysfs_wait_q);

        return rval;
}


/**
 * megaraid_sysfs_free_resources - free sysfs related resources
 * @adapter        : controller's soft state
 *
 * Free packets allocated for sysfs FW commands
 */
static void
megaraid_sysfs_free_resources(adapter_t *adapter)
{
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);

        kfree(raid_dev->sysfs_uioc);
        kfree(raid_dev->sysfs_mbox64);

        if (raid_dev->sysfs_buffer) {
                pci_free_consistent(adapter->pdev, PAGE_SIZE,
                        raid_dev->sysfs_buffer, raid_dev->sysfs_buffer_dma);
        }
}


/**
 * megaraid_sysfs_get_ldmap_done - callback for get ldmap
 * @uioc        : completed packet
 *
 * Callback routine called in the ISR/tasklet context for get ldmap call
 */
static void
megaraid_sysfs_get_ldmap_done(uioc_t *uioc)
{
        adapter_t        *adapter = (adapter_t *)uioc->buf_vaddr;
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);

        uioc->status = 0;

        wake_up(&raid_dev->sysfs_wait_q);
}


/**
 * megaraid_sysfs_get_ldmap_timeout - timeout handling for get ldmap
 * @data        : timed out packet
 *
 * Timeout routine to recover and return to application, in case the adapter
 * has stopped responding. A timeout of 60 seconds for this command seems like
 * a good value.
 */
static void
megaraid_sysfs_get_ldmap_timeout(unsigned long data)
{
        uioc_t                *uioc = (uioc_t *)data;
        adapter_t        *adapter = (adapter_t *)uioc->buf_vaddr;
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);

        uioc->status = -ETIME;

        wake_up(&raid_dev->sysfs_wait_q);
}


/**
 * megaraid_sysfs_get_ldmap - get update logical drive map
 * @adapter        : controller's soft state
 *
 * This routine will be called whenever user reads the logical drive
 * attributes, go get the current logical drive mapping table from the
 * firmware. We use the management API's to issue commands to the controller.
 *
 * NOTE: The commands issuance functionality is not generalized and
 * implemented in context of "get ld map" command only. If required, the
 * command issuance logical can be trivially pulled out and implemented as a
 * standalone libary. For now, this should suffice since there is no other
 * user of this interface.
 *
 * Return 0 on success.
 * Return -1 on failure.
 */
static int
megaraid_sysfs_get_ldmap(adapter_t *adapter)
{
        mraid_device_t                *raid_dev = ADAP2RAIDDEV(adapter);
        uioc_t                        *uioc;
        mbox64_t                *mbox64;
        mbox_t                        *mbox;
        char                        *raw_mbox;
        struct timer_list        sysfs_timer;
        struct timer_list        *timerp;
        caddr_t                        ldmap;
        int                        rval = 0;

        /*
         * Allow only one read at a time to go through the sysfs attributes
         */
        mutex_lock(&raid_dev->sysfs_mtx);

        uioc        = raid_dev->sysfs_uioc;
        mbox64        = raid_dev->sysfs_mbox64;
        ldmap        = raid_dev->sysfs_buffer;

        memset(uioc, 0, sizeof(uioc_t));
        memset(mbox64, 0, sizeof(mbox64_t));
        memset(ldmap, 0, sizeof(raid_dev->curr_ldmap));

        mbox                = &mbox64->mbox32;
        raw_mbox        = (char *)mbox;
        uioc->cmdbuf    = (uint64_t)(unsigned long)mbox64;
        uioc->buf_vaddr        = (caddr_t)adapter;
        uioc->status        = -ENODATA;
        uioc->done        = megaraid_sysfs_get_ldmap_done;

        /*
         * Prepare the mailbox packet to get the current logical drive mapping
         * table
         */
        mbox->xferaddr = (uint32_t)raid_dev->sysfs_buffer_dma;

        raw_mbox[0] = FC_DEL_LOGDRV;
        raw_mbox[2] = OP_GET_LDID_MAP;

        /*
         * Setup a timer to recover from a non-responding controller
         */
        timerp        = &sysfs_timer;
        init_timer(timerp);

        timerp->function        = megaraid_sysfs_get_ldmap_timeout;
        timerp->data                = (unsigned long)uioc;
        timerp->expires                = jiffies + 60 * HZ;

        add_timer(timerp);

        /*
         * Send the command to the firmware
         */
        rval = megaraid_mbox_mm_command(adapter, uioc);

        if (rval == 0) {        // command successfully issued
                wait_event(raid_dev->sysfs_wait_q, (uioc->status != -ENODATA));

                /*
                 * Check if the command timed out
                 */
                if (uioc->status == -ETIME) {
                        con_log(CL_ANN, (KERN_NOTICE
                                "megaraid: sysfs get ld map timed out\n"));

                        rval = -ETIME;
                }
                else {
                        rval = mbox->status;
                }

                if (rval == 0) {
                        memcpy(raid_dev->curr_ldmap, ldmap,
                                sizeof(raid_dev->curr_ldmap));
                }
                else {
                        con_log(CL_ANN, (KERN_NOTICE
                                "megaraid: get ld map failed with %x\n", rval));
                }
        }
        else {
                con_log(CL_ANN, (KERN_NOTICE
                        "megaraid: could not issue ldmap command:%x\n", rval));
        }


        del_timer_sync(timerp);

        mutex_unlock(&raid_dev->sysfs_mtx);

        return rval;
}


/**
 * megaraid_sysfs_show_app_hndl - display application handle for this adapter
 * @cdev        : class device object representation for the host
 * @buf                : buffer to send data to
 *
 * Display the handle used by the applications while executing management
 * tasks on the adapter. We invoke a management module API to get the adapter
 * handle, since we do not interface with applications directly.
 */
static ssize_t
megaraid_sysfs_show_app_hndl(struct device *dev, struct device_attribute *attr,
                             char *buf)
{
        struct Scsi_Host *shost = class_to_shost(dev);
        adapter_t        *adapter = (adapter_t *)SCSIHOST2ADAP(shost);
        uint32_t        app_hndl;

        app_hndl = mraid_mm_adapter_app_handle(adapter->unique_id);

        return snprintf(buf, 8, "%u\n", app_hndl);
}


/**
 * megaraid_sysfs_show_ldnum - display the logical drive number for this device
 * @dev                : device object representation for the scsi device
 * @attr        : device attribute to show
 * @buf                : buffer to send data to
 *
 * Display the logical drive number for the device in question, if it a valid
 * logical drive. For physical devices, "-1" is returned.
 *
 * The logical drive number is displayed in following format:
 *
 * <SCSI ID> <LD NUM> <LD STICKY ID> <APP ADAPTER HANDLE>
 *
 *   <int>     <int>       <int>            <int>
 */
static ssize_t
megaraid_sysfs_show_ldnum(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct scsi_device *sdev = to_scsi_device(dev);
        adapter_t        *adapter = (adapter_t *)SCSIHOST2ADAP(sdev->host);
        mraid_device_t        *raid_dev = ADAP2RAIDDEV(adapter);
        int                scsi_id = -1;
        int                logical_drv = -1;
        int                ldid_map = -1;
        uint32_t        app_hndl = 0;
        int                mapped_sdev_id;
        int                rval;
        int                i;

        if (raid_dev->random_del_supported &&
                        MRAID_IS_LOGICAL_SDEV(adapter, sdev)) {

                rval = megaraid_sysfs_get_ldmap(adapter);
                if (rval == 0) {

                        for (i = 0; i < MAX_LOGICAL_DRIVES_40LD; i++) {

                                mapped_sdev_id = sdev->id;

                                if (sdev->id > adapter->init_id) {
                                        mapped_sdev_id -= 1;
                                }

                                if (raid_dev->curr_ldmap[i] == mapped_sdev_id) {

                                        scsi_id = sdev->id;

                                        logical_drv = i;

                                        ldid_map = raid_dev->curr_ldmap[i];

                                        app_hndl = mraid_mm_adapter_app_handle(
                                                        adapter->unique_id);

                                        break;
                                }
                        }
                }
                else {
                        con_log(CL_ANN, (KERN_NOTICE
                                "megaraid: sysfs get ld map failed: %x\n",
                                rval));
                }
        }

        return snprintf(buf, 36, "%d %d %d %d\n", scsi_id, logical_drv,
                        ldid_map, app_hndl);
}


/*
 * END: Mailbox Low Level Driver
 */
module_init(megaraid_init);
module_exit(megaraid_exit);

/* vim: set ts=8 sw=8 tw=78 ai si: */