[SCSI] MegaRAID SAS RAID: new driver

Signed-off-by: Sreenivas Bagalkote <Sreenivas.Bagalkote@lsil.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

5 files changed, 3958 insertions, 0 deletions

diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 1e4edbdf273..48529d180ca 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -99,6 +99,7 @@ obj-$(CONFIG_SCSI_DC395x)	+= dc395x.o
 obj-$(CONFIG_SCSI_DC390T)	+= tmscsim.o
 obj-$(CONFIG_MEGARAID_LEGACY)	+= megaraid.o
 obj-$(CONFIG_MEGARAID_NEWGEN)	+= megaraid/
+obj-$(CONFIG_MEGARAID_SAS)	+= megaraid/
 obj-$(CONFIG_SCSI_ACARD)	+= atp870u.o
 obj-$(CONFIG_SCSI_SUNESP)	+= esp.o
 obj-$(CONFIG_SCSI_GDTH)		+= gdth.o
diff --git a/drivers/scsi/megaraid/Kconfig.megaraid b/drivers/scsi/megaraid/Kconfig.megaraid
index 917d591d90b..7363e12663a 100644
--- a/drivers/scsi/megaraid/Kconfig.megaraid
+++ b/drivers/scsi/megaraid/Kconfig.megaraid
@@ -76,3 +76,12 @@ config MEGARAID_LEGACY
 	To compile this driver as a module, choose M here: the
 	module will be called megaraid
 endif
+
+config MEGARAID_SAS
+	tristate "LSI Logic MegaRAID SAS RAID Module"
+	depends on PCI && SCSI
+	help
+	Module for LSI Logic's SAS based RAID controllers.
+	To compile this driver as a module, choose 'm' here.
+	Module will be called megaraid_sas
+
diff --git a/drivers/scsi/megaraid/Makefile b/drivers/scsi/megaraid/Makefile
index 6dd99f27572..f469915b97c 100644
--- a/drivers/scsi/megaraid/Makefile
+++ b/drivers/scsi/megaraid/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_MEGARAID_MM)	+= megaraid_mm.o
 obj-$(CONFIG_MEGARAID_MAILBOX)	+= megaraid_mbox.o
+obj-$(CONFIG_MEGARAID_SAS)	+= megaraid_sas.o
diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
new file mode 100644
index 00000000000..1b3148e842a
--- /dev/null
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -0,0 +1,2805 @@
+/*
+ *
+ *		Linux MegaRAID driver for SAS based RAID controllers
+ *
+ * Copyright (c) 2003-2005  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_sas.c
+ * Version	: v00.00.02.00-rc4
+ *
+ * Authors:
+ * 	Sreenivas Bagalkote	<Sreenivas.Bagalkote@lsil.com>
+ * 	Sumant Patro		<Sumant.Patro@lsil.com>
+ *
+ * List of supported controllers
+ *
+ * OEM	Product Name			VID	DID	SSVID	SSID
+ * ---	------------			---	---	----	----
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/list.h>
+#include <linux/version.h>
+#include <linux/moduleparam.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/uio.h>
+#include <asm/uaccess.h>
+#include <linux/compat.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+#include "megaraid_sas.h"
+
+MODULE_LICENSE("GPL");
+MODULE_VERSION(MEGASAS_VERSION);
+MODULE_AUTHOR("sreenivas.bagalkote@lsil.com");
+MODULE_DESCRIPTION("LSI Logic MegaRAID SAS Driver");
+
+/*
+ * PCI ID table for all supported controllers
+ */
+static struct pci_device_id megasas_pci_table[] = {
+
+	{
+	 PCI_VENDOR_ID_LSI_LOGIC,
+	 PCI_DEVICE_ID_LSI_SAS1064R,
+	 PCI_ANY_ID,
+	 PCI_ANY_ID,
+	 },
+	{
+	 PCI_VENDOR_ID_DELL,
+	 PCI_DEVICE_ID_DELL_PERC5,
+	 PCI_ANY_ID,
+	 PCI_ANY_ID,
+	 },
+	{0}			/* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(pci, megasas_pci_table);
+
+static int megasas_mgmt_majorno;
+static struct megasas_mgmt_info megasas_mgmt_info;
+static struct fasync_struct *megasas_async_queue;
+static DECLARE_MUTEX(megasas_async_queue_mutex);
+
+/**
+ * megasas_get_cmd -	Get a command from the free pool
+ * @instance:		Adapter soft state
+ *
+ * Returns a free command from the pool
+ */
+static inline struct megasas_cmd *megasas_get_cmd(struct megasas_instance
+						  *instance)
+{
+	unsigned long flags;
+	struct megasas_cmd *cmd = NULL;
+
+	spin_lock_irqsave(&instance->cmd_pool_lock, flags);
+
+	if (!list_empty(&instance->cmd_pool)) {
+		cmd = list_entry((&instance->cmd_pool)->next,
+				 struct megasas_cmd, list);
+		list_del_init(&cmd->list);
+	} else {
+		printk(KERN_ERR "megasas: Command pool empty!\n");
+	}
+
+	spin_unlock_irqrestore(&instance->cmd_pool_lock, flags);
+	return cmd;
+}
+
+/**
+ * megasas_return_cmd -	Return a cmd to free command pool
+ * @instance:		Adapter soft state
+ * @cmd:		Command packet to be returned to free command pool
+ */
+static inline void
+megasas_return_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&instance->cmd_pool_lock, flags);
+
+	cmd->scmd = NULL;
+	list_add_tail(&cmd->list, &instance->cmd_pool);
+
+	spin_unlock_irqrestore(&instance->cmd_pool_lock, flags);
+}
+
+/**
+ * megasas_enable_intr -	Enables interrupts
+ * @regs:			MFI register set
+ */
+static inline void
+megasas_enable_intr(struct megasas_register_set __iomem * regs)
+{
+	writel(1, &(regs)->outbound_intr_mask);
+
+	/* Dummy readl to force pci flush */
+	readl(&regs->outbound_intr_mask);
+}
+
+/**
+ * megasas_disable_intr -	Disables interrupts
+ * @regs:			MFI register set
+ */
+static inline void
+megasas_disable_intr(struct megasas_register_set __iomem * regs)
+{
+	u32 mask = readl(&regs->outbound_intr_mask) & (~0x00000001);
+	writel(mask, &regs->outbound_intr_mask);
+
+	/* Dummy readl to force pci flush */
+	readl(&regs->outbound_intr_mask);
+}
+
+/**
+ * megasas_issue_polled -	Issues a polling command
+ * @instance:			Adapter soft state
+ * @cmd:			Command packet to be issued 
+ *
+ * For polling, MFI requires the cmd_status to be set to 0xFF before posting.
+ */
+static int
+megasas_issue_polled(struct megasas_instance *instance, struct megasas_cmd *cmd)
+{
+	int i;
+	u32 msecs = MFI_POLL_TIMEOUT_SECS * 1000;
+
+	struct megasas_header *frame_hdr = &cmd->frame->hdr;
+
+	frame_hdr->cmd_status = 0xFF;
+	frame_hdr->flags |= MFI_FRAME_DONT_POST_IN_REPLY_QUEUE;
+
+	/*
+	 * Issue the frame using inbound queue port
+	 */
+	writel(cmd->frame_phys_addr >> 3,
+	       &instance->reg_set->inbound_queue_port);
+
+	/*
+	 * Wait for cmd_status to change
+	 */
+	for (i = 0; (i < msecs) && (frame_hdr->cmd_status == 0xff); i++) {
+		rmb();
+		msleep(1);
+	}
+
+	if (frame_hdr->cmd_status == 0xff)
+		return -ETIME;
+
+	return 0;
+}
+
+/**
+ * megasas_issue_blocked_cmd -	Synchronous wrapper around regular FW cmds
+ * @instance:			Adapter soft state
+ * @cmd:			Command to be issued
+ *
+ * This function waits on an event for the command to be returned from ISR.
+ * Used to issue ioctl commands.
+ */
+static int
+megasas_issue_blocked_cmd(struct megasas_instance *instance,
+			  struct megasas_cmd *cmd)
+{
+	cmd->cmd_status = ENODATA;
+
+	writel(cmd->frame_phys_addr >> 3,
+	       &instance->reg_set->inbound_queue_port);
+
+	wait_event(instance->int_cmd_wait_q, (cmd->cmd_status != ENODATA));
+
+	return 0;
+}
+
+/**
+ * megasas_issue_blocked_abort_cmd -	Aborts previously issued cmd
+ * @instance:				Adapter soft state
+ * @cmd_to_abort:			Previously issued cmd to be aborted
+ *
+ * MFI firmware can abort previously issued AEN comamnd (automatic event
+ * notification). The megasas_issue_blocked_abort_cmd() issues such abort
+ * cmd and blocks till it is completed.
+ */
+static int
+megasas_issue_blocked_abort_cmd(struct megasas_instance *instance,
+				struct megasas_cmd *cmd_to_abort)
+{
+	struct megasas_cmd *cmd;
+	struct megasas_abort_frame *abort_fr;
+
+	cmd = megasas_get_cmd(instance);
+
+	if (!cmd)
+		return -1;
+
+	abort_fr = &cmd->frame->abort;
+
+	/*
+	 * Prepare and issue the abort frame
+	 */
+	abort_fr->cmd = MFI_CMD_ABORT;
+	abort_fr->cmd_status = 0xFF;
+	abort_fr->flags = 0;
+	abort_fr->abort_context = cmd_to_abort->index;
+	abort_fr->abort_mfi_phys_addr_lo = cmd_to_abort->frame_phys_addr;
+	abort_fr->abort_mfi_phys_addr_hi = 0;
+
+	cmd->sync_cmd = 1;
+	cmd->cmd_status = 0xFF;
+
+	writel(cmd->frame_phys_addr >> 3,
+	       &instance->reg_set->inbound_queue_port);
+
+	/*
+	 * Wait for this cmd to complete
+	 */
+	wait_event(instance->abort_cmd_wait_q, (cmd->cmd_status != 0xFF));
+
+	megasas_return_cmd(instance, cmd);
+	return 0;
+}
+
+/**
+ * megasas_make_sgl32 -	Prepares 32-bit SGL
+ * @instance:		Adapter soft state
+ * @scp:		SCSI command from the mid-layer
+ * @mfi_sgl:		SGL to be filled in
+ *
+ * If successful, this function returns the number of SG elements. Otherwise,
+ * it returnes -1.
+ */
+static inline int
+megasas_make_sgl32(struct megasas_instance *instance, struct scsi_cmnd *scp,
+		   union megasas_sgl *mfi_sgl)
+{
+	int i;
+	int sge_count;
+	struct scatterlist *os_sgl;
+
+	/*
+	 * Return 0 if there is no data transfer
+	 */
+	if (!scp->request_buffer || !scp->request_bufflen)
+		return 0;
+
+	if (!scp->use_sg) {
+		mfi_sgl->sge32[0].phys_addr = pci_map_single(instance->pdev,
+							     scp->
+							     request_buffer,
+							     scp->
+							     request_bufflen,
+							     scp->
+							     sc_data_direction);
+		mfi_sgl->sge32[0].length = scp->request_bufflen;
+
+		return 1;
+	}
+
+	os_sgl = (struct scatterlist *)scp->request_buffer;
+	sge_count = pci_map_sg(instance->pdev, os_sgl, scp->use_sg,
+			       scp->sc_data_direction);
+
+	for (i = 0; i < sge_count; i++, os_sgl++) {
+		mfi_sgl->sge32[i].length = sg_dma_len(os_sgl);
+		mfi_sgl->sge32[i].phys_addr = sg_dma_address(os_sgl);
+	}
+
+	return sge_count;
+}
+
+/**
+ * megasas_make_sgl64 -	Prepares 64-bit SGL
+ * @instance:		Adapter soft state
+ * @scp:		SCSI command from the mid-layer
+ * @mfi_sgl:		SGL to be filled in
+ *
+ * If successful, this function returns the number of SG elements. Otherwise,
+ * it returnes -1.
+ */
+static inline int
+megasas_make_sgl64(struct megasas_instance *instance, struct scsi_cmnd *scp,
+		   union megasas_sgl *mfi_sgl)
+{
+	int i;
+	int sge_count;
+	struct scatterlist *os_sgl;
+
+	/*
+	 * Return 0 if there is no data transfer
+	 */
+	if (!scp->request_buffer || !scp->request_bufflen)
+		return 0;
+
+	if (!scp->use_sg) {
+		mfi_sgl->sge64[0].phys_addr = pci_map_single(instance->pdev,
+							     scp->
+							     request_buffer,
+							     scp->
+							     request_bufflen,
+							     scp->
+							     sc_data_direction);
+
+		mfi_sgl->sge64[0].length = scp->request_bufflen;
+
+		return 1;
+	}
+
+	os_sgl = (struct scatterlist *)scp->request_buffer;
+	sge_count = pci_map_sg(instance->pdev, os_sgl, scp->use_sg,
+			       scp->sc_data_direction);
+
+	for (i = 0; i < sge_count; i++, os_sgl++) {
+		mfi_sgl->sge64[i].length = sg_dma_len(os_sgl);
+		mfi_sgl->sge64[i].phys_addr = sg_dma_address(os_sgl);
+	}
+
+	return sge_count;
+}
+
+/**
+ * megasas_build_dcdb -	Prepares a direct cdb (DCDB) command
+ * @instance:		Adapter soft state
+ * @scp:		SCSI command
+ * @cmd:		Command to be prepared in
+ *
+ * This function prepares CDB commands. These are typcially pass-through
+ * commands to the devices.
+ */
+static inline int
+megasas_build_dcdb(struct megasas_instance *instance, struct scsi_cmnd *scp,
+		   struct megasas_cmd *cmd)
+{
+	u32 sge_sz;
+	int sge_bytes;
+	u32 is_logical;
+	u32 device_id;
+	u16 flags = 0;
+	struct megasas_pthru_frame *pthru;
+
+	is_logical = MEGASAS_IS_LOGICAL(scp);
+	device_id = MEGASAS_DEV_INDEX(instance, scp);
+	pthru = (struct megasas_pthru_frame *)cmd->frame;
+
+	if (scp->sc_data_direction == PCI_DMA_TODEVICE)
+		flags = MFI_FRAME_DIR_WRITE;
+	else if (scp->sc_data_direction == PCI_DMA_FROMDEVICE)
+		flags = MFI_FRAME_DIR_READ;
+	else if (scp->sc_data_direction == PCI_DMA_NONE)
+		flags = MFI_FRAME_DIR_NONE;
+
+	/*
+	 * Prepare the DCDB frame
+	 */
+	pthru->cmd = (is_logical) ? MFI_CMD_LD_SCSI_IO : MFI_CMD_PD_SCSI_IO;
+	pthru->cmd_status = 0x0;
+	pthru->scsi_status = 0x0;
+	pthru->target_id = device_id;
+	pthru->lun = scp->device->lun;
+	pthru->cdb_len = scp->cmd_len;
+	pthru->timeout = 0;
+	pthru->flags = flags;
+	pthru->data_xfer_len = scp->request_bufflen;
+
+	memcpy(pthru->cdb, scp->cmnd, scp->cmd_len);
+
+	/*
+	 * Construct SGL
+	 */
+	sge_sz = (IS_DMA64) ? sizeof(struct megasas_sge64) :
+	    sizeof(struct megasas_sge32);
+
+	if (IS_DMA64) {
+		pthru->flags |= MFI_FRAME_SGL64;
+		pthru->sge_count = megasas_make_sgl64(instance, scp,
+						      &pthru->sgl);
+	} else
+		pthru->sge_count = megasas_make_sgl32(instance, scp,
+						      &pthru->sgl);
+
+	/*
+	 * Sense info specific
+	 */
+	pthru->sense_len = SCSI_SENSE_BUFFERSIZE;
+	pthru->sense_buf_phys_addr_hi = 0;
+	pthru->sense_buf_phys_addr_lo = cmd->sense_phys_addr;
+
+	sge_bytes = sge_sz * pthru->sge_count;
+
+	/*
+	 * Compute the total number of frames this command consumes. FW uses
+	 * this number to pull sufficient number of frames from host memory.
+	 */
+	cmd->frame_count = (sge_bytes / MEGAMFI_FRAME_SIZE) +
+	    ((sge_bytes % MEGAMFI_FRAME_SIZE) ? 1 : 0) + 1;
+
+	if (cmd->frame_count > 7)
+		cmd->frame_count = 8;
+
+	return cmd->frame_count;
+}
+
+/**
+ * megasas_build_ldio -	Prepares IOs to logical devices
+ * @instance:		Adapter soft state
+ * @scp:		SCSI command
+ * @cmd:		Command to to be prepared
+ *
+ * Frames (and accompanying SGLs) for regular SCSI IOs use this function.
+ */
+static inline int
+megasas_build_ldio(struct megasas_instance *instance, struct scsi_cmnd *scp,
+		   struct megasas_cmd *cmd)
+{
+	u32 sge_sz;
+	int sge_bytes;
+	u32 device_id;
+	u8 sc = scp->cmnd[0];
+	u16 flags = 0;
+	struct megasas_io_frame *ldio;
+
+	device_id = MEGASAS_DEV_INDEX(instance, scp);
+	ldio = (struct megasas_io_frame *)cmd->frame;
+
+	if (scp->sc_data_direction == PCI_DMA_TODEVICE)
+		flags = MFI_FRAME_DIR_WRITE;
+	else if (scp->sc_data_direction == PCI_DMA_FROMDEVICE)
+		flags = MFI_FRAME_DIR_READ;
+
+	/*
+	 * Preare the Logical IO frame: 2nd bit is zero for all read cmds
+	 */
+	ldio->cmd = (sc & 0x02) ? MFI_CMD_LD_WRITE : MFI_CMD_LD_READ;
+	ldio->cmd_status = 0x0;
+	ldio->scsi_status = 0x0;
+	ldio->target_id = device_id;
+	ldio->timeout = 0;
+	ldio->reserved_0 = 0;
+	ldio->pad_0 = 0;
+	ldio->flags = flags;
+	ldio->start_lba_hi = 0;
+	ldio->access_byte = (scp->cmd_len != 6) ? scp->cmnd[1] : 0;
+
+	/*
+	 * 6-byte READ(0x08) or WRITE(0x0A) cdb
+	 */
+	if (scp->cmd_len == 6) {
+		ldio->lba_count = (u32) scp->cmnd[4];
+		ldio->start_lba_lo = ((u32) scp->cmnd[1] << 16) |
+		    ((u32) scp->cmnd[2] << 8) | (u32) scp->cmnd[3];
+
+		ldio->start_lba_lo &= 0x1FFFFF;
+	}
+
+	/*
+	 * 10-byte READ(0x28) or WRITE(0x2A) cdb
+	 */
+	else if (scp->cmd_len == 10) {
+		ldio->lba_count = (u32) scp->cmnd[8] |
+		    ((u32) scp->cmnd[7] << 8);
+		ldio->start_lba_lo = ((u32) scp->cmnd[2] << 24) |
+		    ((u32) scp->cmnd[3] << 16) |
+		    ((u32) scp->cmnd[4] << 8) | (u32) scp->cmnd[5];
+	}
+
+	/*
+	 * 12-byte READ(0xA8) or WRITE(0xAA) cdb
+	 */
+	else if (scp->cmd_len == 12) {
+		ldio->lba_count = ((u32) scp->cmnd[6] << 24) |
+		    ((u32) scp->cmnd[7] << 16) |
+		    ((u32) scp->cmnd[8] << 8) | (u32) scp->cmnd[9];
+
+		ldio->start_lba_lo = ((u32) scp->cmnd[2] << 24) |
+		    ((u32) scp->cmnd[3] << 16) |
+		    ((u32) scp->cmnd[4] << 8) | (u32) scp->cmnd[5];
+	}
+
+	/*
+	 * 16-byte READ(0x88) or WRITE(0x8A) cdb
+	 */
+	else if (scp->cmd_len == 16) {
+		ldio->lba_count = ((u32) scp->cmnd[10] << 24) |
+		    ((u32) scp->cmnd[11] << 16) |
+		    ((u32) scp->cmnd[12] << 8) | (u32) scp->cmnd[13];
+
+		ldio->start_lba_lo = ((u32) scp->cmnd[6] << 24) |
+		    ((u32) scp->cmnd[7] << 16) |
+		    ((u32) scp->cmnd[8] << 8) | (u32) scp->cmnd[9];
+
+		ldio->start_lba_hi = ((u32) scp->cmnd[2] << 24) |
+		    ((u32) scp->cmnd[3] << 16) |
+		    ((u32) scp->cmnd[4] << 8) | (u32) scp->cmnd[5];
+
+	}
+
+	/*
+	 * Construct SGL
+	 */
+	sge_sz = (IS_DMA64) ? sizeof(struct megasas_sge64) :
+	    sizeof(struct megasas_sge32);
+
+	if (IS_DMA64) {
+		ldio->flags |= MFI_FRAME_SGL64;
+		ldio->sge_count = megasas_make_sgl64(instance, scp, &ldio->sgl);
+	} else
+		ldio->sge_count = megasas_make_sgl32(instance, scp, &ldio->sgl);
+
+	/*
+	 * Sense info specific
+	 */
+	ldio->sense_len = SCSI_SENSE_BUFFERSIZE;
+	ldio->sense_buf_phys_addr_hi = 0;
+	ldio->sense_buf_phys_addr_lo = cmd->sense_phys_addr;
+
+	sge_bytes = sge_sz * ldio->sge_count;
+
+	cmd->frame_count = (sge_bytes / MEGAMFI_FRAME_SIZE) +
+	    ((sge_bytes % MEGAMFI_FRAME_SIZE) ? 1 : 0) + 1;
+
+	if (cmd->frame_count > 7)
+		cmd->frame_count = 8;
+
+	return cmd->frame_count;
+}
+
+/**
+ * megasas_build_cmd -	Prepares a command packet
+ * @instance:		Adapter soft state
+ * @scp:		SCSI command
+ * @frame_count:	[OUT] Number of frames used to prepare this command
+ */
+static inline struct megasas_cmd *megasas_build_cmd(struct megasas_instance
+						    *instance,
+						    struct scsi_cmnd *scp,
+						    int *frame_count)
+{
+	u32 logical_cmd;
+	struct megasas_cmd *cmd;
+
+	/*
+	 * Find out if this is logical or physical drive command.
+	 */
+	logical_cmd = MEGASAS_IS_LOGICAL(scp);
+
+	/*
+	 * Logical drive command
+	 */
+	if (logical_cmd) {
+
+		if (scp->device->id >= MEGASAS_MAX_LD) {
+			scp->result = DID_BAD_TARGET << 16;
+			return NULL;
+		}
+
+		switch (scp->cmnd[0]) {
+
+		case READ_10:
+		case WRITE_10:
+		case READ_12:
+		case WRITE_12:
+		case READ_6:
+		case WRITE_6:
+		case READ_16:
+		case WRITE_16:
+			/*
+			 * Fail for LUN > 0
+			 */
+			if (scp->device->lun) {
+				scp->result = DID_BAD_TARGET << 16;
+				return NULL;
+			}
+
+			cmd = megasas_get_cmd(instance);
+
+			if (!cmd) {
+				scp->result = DID_IMM_RETRY << 16;
+				return NULL;
+			}
+
+			*frame_count = megasas_build_ldio(instance, scp, cmd);
+
+			if (!(*frame_count)) {
+				megasas_return_cmd(instance, cmd);
+				return NULL;
+			}
+
+			return cmd;
+
+		default:
+			/*
+			 * Fail for LUN > 0
+			 */
+			if (scp->device->lun) {
+				scp->result = DID_BAD_TARGET << 16;
+				return NULL;
+			}
+
+			cmd = megasas_get_cmd(instance);
+
+			if (!cmd) {
+				scp->result = DID_IMM_RETRY << 16;
+				return NULL;
+			}
+
+			*frame_count = megasas_build_dcdb(instance, scp, cmd);
+
+			if (!(*frame_count)) {
+				megasas_return_cmd(instance, cmd);
+				return NULL;
+			}
+
+			return cmd;
+		}
+	} else {
+		cmd = megasas_get_cmd(instance);
+
+		if (!cmd) {
+			scp->result = DID_IMM_RETRY << 16;
+			return NULL;
+		}
+
+		*frame_count = megasas_build_dcdb(instance, scp, cmd);
+
+		if (!(*frame_count)) {
+			megasas_return_cmd(instance, cmd);
+			return NULL;
+		}
+
+		return cmd;
+	}
+
+	return NULL;
+}
+
+/**
+ * megasas_queue_command -	Queue entry point
+ * @scmd:			SCSI command to be queued
+ * @done:			Callback entry point
+ */
+static int
+megasas_queue_command(struct scsi_cmnd *scmd, void (*done) (struct scsi_cmnd *))
+{
+	u32 frame_count;
+	unsigned long flags;
+	struct megasas_cmd *cmd;
+	struct megasas_instance *instance;
+
+	instance = (struct megasas_instance *)
+	    scmd->device->host->hostdata;
+	scmd->scsi_done = done;
+	scmd->result = 0;
+
+	cmd = megasas_build_cmd(instance, scmd, &frame_count);
+
+	if (!cmd) {
+		done(scmd);
+		return 0;
+	}
+
+	cmd->scmd = scmd;
+	scmd->SCp.ptr = (char *)cmd;
+	scmd->SCp.sent_command = jiffies;
+
+	/*
+	 * Issue the command to the FW
+	 */
+	spin_lock_irqsave(&instance->instance_lock, flags);
+	instance->fw_outstanding++;
+	spin_unlock_irqrestore(&instance->instance_lock, flags);
+
+	writel(((cmd->frame_phys_addr >> 3) | (cmd->frame_count - 1)),
+	       &instance->reg_set->inbound_queue_port);
+
+	return 0;
+}
+
+/**
+ * megasas_wait_for_outstanding -	Wait for all outstanding cmds
+ * @instance:				Adapter soft state
+ *
+ * This function waits for upto MEGASAS_RESET_WAIT_TIME seconds for FW to
+ * complete all its outstanding commands. Returns error if one or more IOs
+ * are pending after this time period. It also marks the controller dead.
+ */
+static int megasas_wait_for_outstanding(struct megasas_instance *instance)
+{
+	int i;
+	u32 wait_time = MEGASAS_RESET_WAIT_TIME;
+
+	for (i = 0; i < wait_time; i++) {
+
+		if (!instance->fw_outstanding)
+			break;
+
+		if (!(i % MEGASAS_RESET_NOTICE_INTERVAL)) {
+			printk(KERN_NOTICE "megasas: [%2d]waiting for %d "
+			       "commands to complete\n", i,
+			       instance->fw_outstanding);
+		}
+
+		msleep(1000);
+	}
+
+	if (instance->fw_outstanding) {
+		instance->hw_crit_error = 1;
+		return FAILED;
+	}
+
+	return SUCCESS;
+}
+
+/**
+ * megasas_generic_reset -	Generic reset routine
+ * @scmd:			Mid-layer SCSI command
+ *
+ * This routine implements a generic reset handler for device, bus and host
+ * reset requests. Device, bus and host specific reset handlers can use this
+ * function after they do their specific tasks.
+ */
+static int megasas_generic_reset(struct scsi_cmnd *scmd)
+{
+	int ret_val;
+	struct megasas_instance *instance;
+
+	instance = (struct megasas_instance *)scmd->device->host->hostdata;
+
+	printk(KERN_NOTICE "megasas: RESET -%ld cmd=%x <c=%d t=%d l=%d>\n",
+	       scmd->serial_number, scmd->cmnd[0], scmd->device->channel,
+	       scmd->device->id, scmd->device->lun);
+
+	if (instance->hw_crit_error) {
+		printk(KERN_ERR "megasas: cannot recover from previous reset "
+		       "failures\n");
+		return FAILED;
+	}
+
+	spin_unlock(scmd->device->host->host_lock);
+
+	ret_val = megasas_wait_for_outstanding(instance);
+
+	if (ret_val == SUCCESS)
+		printk(KERN_NOTICE "megasas: reset successful \n");
+	else
+		printk(KERN_ERR "megasas: failed to do reset\n");
+
+	spin_lock(scmd->device->host->host_lock);
+
+	return ret_val;
+}
+
+static enum scsi_eh_timer_return megasas_reset_timer(struct scsi_cmnd *scmd)
+{
+	unsigned long seconds;
+
+	if (scmd->SCp.ptr) {
+		seconds = (jiffies - scmd->SCp.sent_command) / HZ;
+
+		if (seconds < 90) {
+			return EH_RESET_TIMER;
+		} else {
+			return EH_NOT_HANDLED;
+		}
+	}
+
+	return EH_HANDLED;
+}
+
+/**
+ * megasas_reset_device -	Device reset handler entry point
+ */
+static int megasas_reset_device(struct scsi_cmnd *scmd)
+{
+	int ret;
+
+	/*
+	 * First wait for all commands to complete
+	 */
+	ret = megasas_generic_reset(scmd);
+
+	return ret;
+}
+
+/**
+ * megasas_reset_bus_host -	Bus & host reset handler entry point
+ */
+static int megasas_reset_bus_host(struct scsi_cmnd *scmd)
+{
+	int ret;
+
+	/*
+	 * Frist wait for all commands to complete
+	 */
+	ret = megasas_generic_reset(scmd);
+
+	return ret;
+}
+
+/**
+ * megasas_service_aen -	Processes an event notification
+ * @instance:			Adapter soft state
+ * @cmd:			AEN command completed by the ISR
+ *
+ * For AEN, driver sends a command down to FW that is held by the FW till an
+ * event occurs. When an event of interest occurs, FW completes the command
+ * that it was previously holding.
+ *
+ * This routines sends SIGIO signal to processes that have registered with the
+ * driver for AEN.
+ */
+static void
+megasas_service_aen(struct megasas_instance *instance, struct megasas_cmd *cmd)
+{
+	/*
+	 * Don't signal app if it is just an aborted previously registered aen
+	 */
+	if (!cmd->abort_aen)
+		kill_fasync(&megasas_async_queue, SIGIO, POLL_IN);
+	else
+		cmd->abort_aen = 0;
+
+	instance->aen_cmd = NULL;
+	megasas_return_cmd(instance, cmd);
+}
+
+/*
+ * Scsi host template for megaraid_sas driver
+ */
+static struct scsi_host_template megasas_template = {
+
+	.module = THIS_MODULE,
+	.name = "LSI Logic SAS based MegaRAID driver",
+	.proc_name = "megaraid_sas",
+	.queuecommand = megasas_queue_command,
+	.eh_device_reset_handler = megasas_reset_device,
+	.eh_bus_reset_handler = megasas_reset_bus_host,
+	.eh_host_reset_handler = megasas_reset_bus_host,
+	.eh_timed_out = megasas_reset_timer,
+	.use_clustering = ENABLE_CLUSTERING,
+};
+
+/**
+ * megasas_complete_int_cmd -	Completes an internal command
+ * @instance:			Adapter soft state
+ * @cmd:			Command to be completed
+ *
+ * The megasas_issue_blocked_cmd() function waits for a command to complete
+ * after it issues a command. This function wakes up that waiting routine by
+ * calling wake_up() on the wait queue.
+ */
+static void
+megasas_complete_int_cmd(struct megasas_instance *instance,
+			 struct megasas_cmd *cmd)
+{
+	cmd->cmd_status = cmd->frame->io.cmd_status;
+
+	if (cmd->cmd_status == ENODATA) {
+		cmd->cmd_status = 0;
+	}
+	wake_up(&instance->int_cmd_wait_q);
+}
+
+/**
+ * megasas_complete_abort -	Completes aborting a command
+ * @instance:			Adapter soft state
+ * @cmd:			Cmd that was issued to abort another cmd
+ *
+ * The megasas_issue_blocked_abort_cmd() function waits on abort_cmd_wait_q 
+ * after it issues an abort on a previously issued command. This function 
+ * wakes up all functions waiting on the same wait queue.
+ */
+static void
+megasas_complete_abort(struct megasas_instance *instance,
+		       struct megasas_cmd *cmd)
+{
+	if (cmd->sync_cmd) {
+		cmd->sync_cmd = 0;
+		cmd->cmd_status = 0;
+		wake_up(&instance->abort_cmd_wait_q);
+	}
+
+	return;
+}
+
+/**
+ * megasas_unmap_sgbuf -	Unmap SG buffers
+ * @instance:			Adapter soft state
+ * @cmd:			Completed command
+ */
+static inline void
+megasas_unmap_sgbuf(struct megasas_instance *instance, struct megasas_cmd *cmd)
+{
+	dma_addr_t buf_h;
+	u8 opcode;
+
+	if (cmd->scmd->use_sg) {
+		pci_unmap_sg(instance->pdev, cmd->scmd->request_buffer,
+			     cmd->scmd->use_sg, cmd->scmd->sc_data_direction);
+		return;
+	}
+
+	if (!cmd->scmd->request_bufflen)
+		return;
+
+	opcode = cmd->frame->hdr.cmd;
+
+	if ((opcode == MFI_CMD_LD_READ) || (opcode == MFI_CMD_LD_WRITE)) {
+		if (IS_DMA64)
+			buf_h = cmd->frame->io.sgl.sge64[0].phys_addr;
+		else
+			buf_h = cmd->frame->io.sgl.sge32[0].phys_addr;
+	} else {
+		if (IS_DMA64)
+			buf_h = cmd->frame->pthru.sgl.sge64[0].phys_addr;
+		else
+			buf_h = cmd->frame->pthru.sgl.sge32[0].phys_addr;
+	}
+
+	pci_unmap_single(instance->pdev, buf_h, cmd->scmd->request_bufflen,
+			 cmd->scmd->sc_data_direction);
+	return;
+}
+
+/**
+ * megasas_complete_cmd -	Completes a command
+ * @instance:			Adapter soft state
+ * @cmd:			Command to be completed
+ * @alt_status:			If non-zero, use this value as status to 
+ * 				SCSI mid-layer instead of the value returned
+ * 				by the FW. This should be used if caller wants
+ * 				an alternate status (as in the case of aborted
+ * 				commands)
+ */
+static inline void
+megasas_complete_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd,
+		     u8 alt_status)
+{
+	int exception = 0;
+	struct megasas_header *hdr = &cmd->frame->hdr;
+	unsigned long flags;
+
+	if (cmd->scmd) {
+		cmd->scmd->SCp.ptr = (char *)0;
+	}
+
+	switch (hdr->cmd) {
+
+	case MFI_CMD_PD_SCSI_IO:
+	case MFI_CMD_LD_SCSI_IO:
+
+		/*
+		 * MFI_CMD_PD_SCSI_IO and MFI_CMD_LD_SCSI_IO could have been
+		 * issued either through an IO path or an IOCTL path. If it
+		 * was via IOCTL, we will send it to internal completion.
+		 */
+		if (cmd->sync_cmd) {
+			cmd->sync_cmd = 0;
+			megasas_complete_int_cmd(instance, cmd);
+			break;
+		}
+
+		/*
+		 * Don't export physical disk devices to mid-layer.
+		 */
+		if (!MEGASAS_IS_LOGICAL(cmd->scmd) &&
+		    (hdr->cmd_status == MFI_STAT_OK) &&
+		    (cmd->scmd->cmnd[0] == INQUIRY)) {
+
+			if (((*(u8 *) cmd->scmd->request_buffer) & 0x1F) ==
+			    TYPE_DISK) {
+				cmd->scmd->result = DID_BAD_TARGET << 16;
+				exception = 1;
+			}
+		}
+
+	case MFI_CMD_LD_READ:
+	case MFI_CMD_LD_WRITE:
+
+		if (alt_status) {
+			cmd->scmd->result = alt_status << 16;
+			exception = 1;
+		}
+
+		if (exception) {
+
+			spin_lock_irqsave(&instance->instance_lock, flags);
+			instance->fw_outstanding--;
+			spin_unlock_irqrestore(&instance->instance_lock, flags);
+
+			megasas_unmap_sgbuf(instance, cmd);
+			cmd->scmd->scsi_done(cmd->scmd);
+			megasas_return_cmd(instance, cmd);
+
+			break;
+		}
+
+		switch (hdr->cmd_status) {
+
+		case MFI_STAT_OK:
+			cmd->scmd->result = DID_OK << 16;
+			break;
+
+		case MFI_STAT_SCSI_IO_FAILED:
+		case MFI_STAT_LD_INIT_IN_PROGRESS:
+			cmd->scmd->result =
+			    (DID_ERROR << 16) | hdr->scsi_status;
+			break;
+
+		case MFI_STAT_SCSI_DONE_WITH_ERROR:
+
+			cmd->scmd->result = (DID_OK << 16) | hdr->scsi_status;
+
+			if (hdr->scsi_status == SAM_STAT_CHECK_CONDITION) {
+				memset(cmd->scmd->sense_buffer, 0,
+				       SCSI_SENSE_BUFFERSIZE);
+				memcpy(cmd->scmd->sense_buffer, cmd->sense,
+				       hdr->sense_len);
+
+				cmd->scmd->result |= DRIVER_SENSE << 24;
+			}
+
+			break;
+
+		case MFI_STAT_LD_OFFLINE:
+		case MFI_STAT_DEVICE_NOT_FOUND:
+			cmd->scmd->result = DID_BAD_TARGET << 16;
+			break;
+
+		default:
+			printk(KERN_DEBUG "megasas: MFI FW status %#x\n",
+			       hdr->cmd_status);
+			cmd->scmd->result = DID_ERROR << 16;
+			break;
+		}
+
+		spin_lock_irqsave(&instance->instance_lock, flags);
+		instance->fw_outstanding--;
+		spin_unlock_irqrestore(&instance->instance_lock, flags);
+
+		megasas_unmap_sgbuf(instance, cmd);
+		cmd->scmd->scsi_done(cmd->scmd);
+		megasas_return_cmd(instance, cmd);
+
+		break;
+
+	case MFI_CMD_SMP:
+	case MFI_CMD_STP:
+	case MFI_CMD_DCMD:
+
+		/*
+		 * See if got an event notification
+		 */
+		if (cmd->frame->dcmd.opcode == MR_DCMD_CTRL_EVENT_WAIT)
+			megasas_service_aen(instance, cmd);
+		else
+			megasas_complete_int_cmd(instance, cmd);
+
+		break;
+
+	case MFI_CMD_ABORT:
+		/*
+		 * Cmd issued to abort another cmd returned
+		 */
+		megasas_complete_abort(instance, cmd);
+		break;
+
+	default:
+		printk("megasas: Unknown command completed! [0x%X]\n",
+		       hdr->cmd);
+		break;
+	}
+}
+
+/**
+ * megasas_deplete_reply_queue -	Processes all completed commands
+ * @instance:				Adapter soft state
+ * @alt_status:				Alternate status to be returned to
+ * 					SCSI mid-layer instead of the status
+ * 					returned by the FW
+ */
+static inline int
+megasas_deplete_reply_queue(struct megasas_instance *instance, u8 alt_status)
+{
+	u32 status;
+	u32 producer;
+	u32 consumer;
+	u32 context;
+	struct megasas_cmd *cmd;