https://github.com/torvalds/linux
Tip revision: a798c10faf62a505d24e5f6213fbaf904a39623f authored by Linus Torvalds on 20 April 2014, 18:08:50 UTC
Linux 3.15-rc2
Linux 3.15-rc2
Tip revision: a798c10
ibmvscsi.c
/* ------------------------------------------------------------
* ibmvscsi.c
* (C) Copyright IBM Corporation 1994, 2004
* Authors: Colin DeVilbiss (devilbis@us.ibm.com)
* Santiago Leon (santil@us.ibm.com)
* Dave Boutcher (sleddog@us.ibm.com)
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* ------------------------------------------------------------
* Emulation of a SCSI host adapter for Virtual I/O devices
*
* This driver supports the SCSI adapter implemented by the IBM
* Power5 firmware. That SCSI adapter is not a physical adapter,
* but allows Linux SCSI peripheral drivers to directly
* access devices in another logical partition on the physical system.
*
* The virtual adapter(s) are present in the open firmware device
* tree just like real adapters.
*
* One of the capabilities provided on these systems is the ability
* to DMA between partitions. The architecture states that for VSCSI,
* the server side is allowed to DMA to and from the client. The client
* is never trusted to DMA to or from the server directly.
*
* Messages are sent between partitions on a "Command/Response Queue"
* (CRQ), which is just a buffer of 16 byte entries in the receiver's
* Senders cannot access the buffer directly, but send messages by
* making a hypervisor call and passing in the 16 bytes. The hypervisor
* puts the message in the next 16 byte space in round-robin fashion,
* turns on the high order bit of the message (the valid bit), and
* generates an interrupt to the receiver (if interrupts are turned on.)
* The receiver just turns off the valid bit when they have copied out
* the message.
*
* The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
* (IU) (as defined in the T10 standard available at www.t10.org), gets
* a DMA address for the message, and sends it to the server as the
* payload of a CRQ message. The server DMAs the SRP IU and processes it,
* including doing any additional data transfers. When it is done, it
* DMAs the SRP response back to the same address as the request came from,
* and sends a CRQ message back to inform the client that the request has
* completed.
*
* TODO: This is currently pretty tied to the IBM pSeries hypervisor
* interfaces. It would be really nice to abstract this above an RDMA
* layer.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/kthread.h>
#include <asm/firmware.h>
#include <asm/vio.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_transport_srp.h>
#include "ibmvscsi.h"
/* The values below are somewhat arbitrary default values, but
* OS/400 will use 3 busses (disks, CDs, tapes, I think.)
* Note that there are 3 bits of channel value, 6 bits of id, and
* 5 bits of LUN.
*/
static int max_id = 64;
static int max_channel = 3;
static int init_timeout = 300;
static int login_timeout = 60;
static int info_timeout = 30;
static int abort_timeout = 60;
static int reset_timeout = 60;
static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
static int fast_fail = 1;
static int client_reserve = 1;
static char partition_name[97] = "UNKNOWN";
static unsigned int partition_number = -1;
static struct scsi_transport_template *ibmvscsi_transport_template;
#define IBMVSCSI_VERSION "1.5.9"
MODULE_DESCRIPTION("IBM Virtual SCSI");
MODULE_AUTHOR("Dave Boutcher");
MODULE_LICENSE("GPL");
MODULE_VERSION(IBMVSCSI_VERSION);
module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(max_channel, "Largest channel value");
module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
module_param_named(max_requests, max_requests, int, S_IRUGO);
MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
module_param_named(fast_fail, fast_fail, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(fast_fail, "Enable fast fail. [Default=1]");
module_param_named(client_reserve, client_reserve, int, S_IRUGO );
MODULE_PARM_DESC(client_reserve, "Attempt client managed reserve/release");
static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
struct ibmvscsi_host_data *hostdata);
/* ------------------------------------------------------------
* Routines for managing the command/response queue
*/
/**
* ibmvscsi_handle_event: - Interrupt handler for crq events
* @irq: number of irq to handle, not used
* @dev_instance: ibmvscsi_host_data of host that received interrupt
*
* Disables interrupts and schedules srp_task
* Always returns IRQ_HANDLED
*/
static irqreturn_t ibmvscsi_handle_event(int irq, void *dev_instance)
{
struct ibmvscsi_host_data *hostdata =
(struct ibmvscsi_host_data *)dev_instance;
vio_disable_interrupts(to_vio_dev(hostdata->dev));
tasklet_schedule(&hostdata->srp_task);
return IRQ_HANDLED;
}
/**
* release_crq_queue: - Deallocates data and unregisters CRQ
* @queue: crq_queue to initialize and register
* @host_data: ibmvscsi_host_data of host
*
* Frees irq, deallocates a page for messages, unmaps dma, and unregisters
* the crq with the hypervisor.
*/
static void ibmvscsi_release_crq_queue(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata,
int max_requests)
{
long rc = 0;
struct vio_dev *vdev = to_vio_dev(hostdata->dev);
free_irq(vdev->irq, (void *)hostdata);
tasklet_kill(&hostdata->srp_task);
do {
if (rc)
msleep(100);
rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
dma_unmap_single(hostdata->dev,
queue->msg_token,
queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
free_page((unsigned long)queue->msgs);
}
/**
* crq_queue_next_crq: - Returns the next entry in message queue
* @queue: crq_queue to use
*
* Returns pointer to next entry in queue, or NULL if there are no new
* entried in the CRQ.
*/
static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
{
struct viosrp_crq *crq;
unsigned long flags;
spin_lock_irqsave(&queue->lock, flags);
crq = &queue->msgs[queue->cur];
if (crq->valid & 0x80) {
if (++queue->cur == queue->size)
queue->cur = 0;
} else
crq = NULL;
spin_unlock_irqrestore(&queue->lock, flags);
return crq;
}
/**
* ibmvscsi_send_crq: - Send a CRQ
* @hostdata: the adapter
* @word1: the first 64 bits of the data
* @word2: the second 64 bits of the data
*/
static int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata,
u64 word1, u64 word2)
{
struct vio_dev *vdev = to_vio_dev(hostdata->dev);
return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
}
/**
* ibmvscsi_task: - Process srps asynchronously
* @data: ibmvscsi_host_data of host
*/
static void ibmvscsi_task(void *data)
{
struct ibmvscsi_host_data *hostdata = (struct ibmvscsi_host_data *)data;
struct vio_dev *vdev = to_vio_dev(hostdata->dev);
struct viosrp_crq *crq;
int done = 0;
while (!done) {
/* Pull all the valid messages off the CRQ */
while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
ibmvscsi_handle_crq(crq, hostdata);
crq->valid = 0x00;
}
vio_enable_interrupts(vdev);
crq = crq_queue_next_crq(&hostdata->queue);
if (crq != NULL) {
vio_disable_interrupts(vdev);
ibmvscsi_handle_crq(crq, hostdata);
crq->valid = 0x00;
} else {
done = 1;
}
}
}
static void gather_partition_info(void)
{
struct device_node *rootdn;
const char *ppartition_name;
const __be32 *p_number_ptr;
/* Retrieve information about this partition */
rootdn = of_find_node_by_path("/");
if (!rootdn) {
return;
}
ppartition_name = of_get_property(rootdn, "ibm,partition-name", NULL);
if (ppartition_name)
strncpy(partition_name, ppartition_name,
sizeof(partition_name));
p_number_ptr = of_get_property(rootdn, "ibm,partition-no", NULL);
if (p_number_ptr)
partition_number = of_read_number(p_number_ptr, 1);
of_node_put(rootdn);
}
static void set_adapter_info(struct ibmvscsi_host_data *hostdata)
{
memset(&hostdata->madapter_info, 0x00,
sizeof(hostdata->madapter_info));
dev_info(hostdata->dev, "SRP_VERSION: %s\n", SRP_VERSION);
strcpy(hostdata->madapter_info.srp_version, SRP_VERSION);
strncpy(hostdata->madapter_info.partition_name, partition_name,
sizeof(hostdata->madapter_info.partition_name));
hostdata->madapter_info.partition_number =
cpu_to_be32(partition_number);
hostdata->madapter_info.mad_version = cpu_to_be32(1);
hostdata->madapter_info.os_type = cpu_to_be32(2);
}
/**
* reset_crq_queue: - resets a crq after a failure
* @queue: crq_queue to initialize and register
* @hostdata: ibmvscsi_host_data of host
*
*/
static int ibmvscsi_reset_crq_queue(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata)
{
int rc = 0;
struct vio_dev *vdev = to_vio_dev(hostdata->dev);
/* Close the CRQ */
do {
if (rc)
msleep(100);
rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
/* Clean out the queue */
memset(queue->msgs, 0x00, PAGE_SIZE);
queue->cur = 0;
set_adapter_info(hostdata);
/* And re-open it again */
rc = plpar_hcall_norets(H_REG_CRQ,
vdev->unit_address,
queue->msg_token, PAGE_SIZE);
if (rc == 2) {
/* Adapter is good, but other end is not ready */
dev_warn(hostdata->dev, "Partner adapter not ready\n");
} else if (rc != 0) {
dev_warn(hostdata->dev, "couldn't register crq--rc 0x%x\n", rc);
}
return rc;
}
/**
* initialize_crq_queue: - Initializes and registers CRQ with hypervisor
* @queue: crq_queue to initialize and register
* @hostdata: ibmvscsi_host_data of host
*
* Allocates a page for messages, maps it for dma, and registers
* the crq with the hypervisor.
* Returns zero on success.
*/
static int ibmvscsi_init_crq_queue(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata,
int max_requests)
{
int rc;
int retrc;
struct vio_dev *vdev = to_vio_dev(hostdata->dev);
queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
if (!queue->msgs)
goto malloc_failed;
queue->size = PAGE_SIZE / sizeof(*queue->msgs);
queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
queue->size * sizeof(*queue->msgs),
DMA_BIDIRECTIONAL);
if (dma_mapping_error(hostdata->dev, queue->msg_token))
goto map_failed;
gather_partition_info();
set_adapter_info(hostdata);
retrc = rc = plpar_hcall_norets(H_REG_CRQ,
vdev->unit_address,
queue->msg_token, PAGE_SIZE);
if (rc == H_RESOURCE)
/* maybe kexecing and resource is busy. try a reset */
rc = ibmvscsi_reset_crq_queue(queue,
hostdata);
if (rc == 2) {
/* Adapter is good, but other end is not ready */
dev_warn(hostdata->dev, "Partner adapter not ready\n");
retrc = 0;
} else if (rc != 0) {
dev_warn(hostdata->dev, "Error %d opening adapter\n", rc);
goto reg_crq_failed;
}
queue->cur = 0;
spin_lock_init(&queue->lock);
tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task,
(unsigned long)hostdata);
if (request_irq(vdev->irq,
ibmvscsi_handle_event,
0, "ibmvscsi", (void *)hostdata) != 0) {
dev_err(hostdata->dev, "couldn't register irq 0x%x\n",
vdev->irq);
goto req_irq_failed;
}
rc = vio_enable_interrupts(vdev);
if (rc != 0) {
dev_err(hostdata->dev, "Error %d enabling interrupts!!!\n", rc);
goto req_irq_failed;
}
return retrc;
req_irq_failed:
tasklet_kill(&hostdata->srp_task);
rc = 0;
do {
if (rc)
msleep(100);
rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
} while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
reg_crq_failed:
dma_unmap_single(hostdata->dev,
queue->msg_token,
queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
map_failed:
free_page((unsigned long)queue->msgs);
malloc_failed:
return -1;
}
/**
* reenable_crq_queue: - reenables a crq after
* @queue: crq_queue to initialize and register
* @hostdata: ibmvscsi_host_data of host
*
*/
static int ibmvscsi_reenable_crq_queue(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata)
{
int rc = 0;
struct vio_dev *vdev = to_vio_dev(hostdata->dev);
/* Re-enable the CRQ */
do {
if (rc)
msleep(100);
rc = plpar_hcall_norets(H_ENABLE_CRQ, vdev->unit_address);
} while ((rc == H_IN_PROGRESS) || (rc == H_BUSY) || (H_IS_LONG_BUSY(rc)));
if (rc)
dev_err(hostdata->dev, "Error %d enabling adapter\n", rc);
return rc;
}
/* ------------------------------------------------------------
* Routines for the event pool and event structs
*/
/**
* initialize_event_pool: - Allocates and initializes the event pool for a host
* @pool: event_pool to be initialized
* @size: Number of events in pool
* @hostdata: ibmvscsi_host_data who owns the event pool
*
* Returns zero on success.
*/
static int initialize_event_pool(struct event_pool *pool,
int size, struct ibmvscsi_host_data *hostdata)
{
int i;
pool->size = size;
pool->next = 0;
pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
if (!pool->events)
return -ENOMEM;
pool->iu_storage =
dma_alloc_coherent(hostdata->dev,
pool->size * sizeof(*pool->iu_storage),
&pool->iu_token, 0);
if (!pool->iu_storage) {
kfree(pool->events);
return -ENOMEM;
}
for (i = 0; i < pool->size; ++i) {
struct srp_event_struct *evt = &pool->events[i];
memset(&evt->crq, 0x00, sizeof(evt->crq));
atomic_set(&evt->free, 1);
evt->crq.valid = 0x80;
evt->crq.IU_length = cpu_to_be16(sizeof(*evt->xfer_iu));
evt->crq.IU_data_ptr = cpu_to_be64(pool->iu_token +
sizeof(*evt->xfer_iu) * i);
evt->xfer_iu = pool->iu_storage + i;
evt->hostdata = hostdata;
evt->ext_list = NULL;
evt->ext_list_token = 0;
}
return 0;
}
/**
* release_event_pool: - Frees memory of an event pool of a host
* @pool: event_pool to be released
* @hostdata: ibmvscsi_host_data who owns the even pool
*
* Returns zero on success.
*/
static void release_event_pool(struct event_pool *pool,
struct ibmvscsi_host_data *hostdata)
{
int i, in_use = 0;
for (i = 0; i < pool->size; ++i) {
if (atomic_read(&pool->events[i].free) != 1)
++in_use;
if (pool->events[i].ext_list) {
dma_free_coherent(hostdata->dev,
SG_ALL * sizeof(struct srp_direct_buf),
pool->events[i].ext_list,
pool->events[i].ext_list_token);
}
}
if (in_use)
dev_warn(hostdata->dev, "releasing event pool with %d "
"events still in use?\n", in_use);
kfree(pool->events);
dma_free_coherent(hostdata->dev,
pool->size * sizeof(*pool->iu_storage),
pool->iu_storage, pool->iu_token);
}
/**
* valid_event_struct: - Determines if event is valid.
* @pool: event_pool that contains the event
* @evt: srp_event_struct to be checked for validity
*
* Returns zero if event is invalid, one otherwise.
*/
static int valid_event_struct(struct event_pool *pool,
struct srp_event_struct *evt)
{
int index = evt - pool->events;
if (index < 0 || index >= pool->size) /* outside of bounds */
return 0;
if (evt != pool->events + index) /* unaligned */
return 0;
return 1;
}
/**
* ibmvscsi_free-event_struct: - Changes status of event to "free"
* @pool: event_pool that contains the event
* @evt: srp_event_struct to be modified
*
*/
static void free_event_struct(struct event_pool *pool,
struct srp_event_struct *evt)
{
if (!valid_event_struct(pool, evt)) {
dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
"(not in pool %p)\n", evt, pool->events);
return;
}
if (atomic_inc_return(&evt->free) != 1) {
dev_err(evt->hostdata->dev, "Freeing event_struct %p "
"which is not in use!\n", evt);
return;
}
}
/**
* get_evt_struct: - Gets the next free event in pool
* @pool: event_pool that contains the events to be searched
*
* Returns the next event in "free" state, and NULL if none are free.
* Note that no synchronization is done here, we assume the host_lock
* will syncrhonze things.
*/
static struct srp_event_struct *get_event_struct(struct event_pool *pool)
{
int i;
int poolsize = pool->size;
int offset = pool->next;
for (i = 0; i < poolsize; i++) {
offset = (offset + 1) % poolsize;
if (!atomic_dec_if_positive(&pool->events[offset].free)) {
pool->next = offset;
return &pool->events[offset];
}
}
printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
return NULL;
}
/**
* init_event_struct: Initialize fields in an event struct that are always
* required.
* @evt: The event
* @done: Routine to call when the event is responded to
* @format: SRP or MAD format
* @timeout: timeout value set in the CRQ
*/
static void init_event_struct(struct srp_event_struct *evt_struct,
void (*done) (struct srp_event_struct *),
u8 format,
int timeout)
{
evt_struct->cmnd = NULL;
evt_struct->cmnd_done = NULL;
evt_struct->sync_srp = NULL;
evt_struct->crq.format = format;
evt_struct->crq.timeout = cpu_to_be16(timeout);
evt_struct->done = done;
}
/* ------------------------------------------------------------
* Routines for receiving SCSI responses from the hosting partition
*/
/**
* set_srp_direction: Set the fields in the srp related to data
* direction and number of buffers based on the direction in
* the scsi_cmnd and the number of buffers
*/
static void set_srp_direction(struct scsi_cmnd *cmd,
struct srp_cmd *srp_cmd,
int numbuf)
{
u8 fmt;
if (numbuf == 0)
return;
if (numbuf == 1)
fmt = SRP_DATA_DESC_DIRECT;
else {
fmt = SRP_DATA_DESC_INDIRECT;
numbuf = min(numbuf, MAX_INDIRECT_BUFS);
if (cmd->sc_data_direction == DMA_TO_DEVICE)
srp_cmd->data_out_desc_cnt = numbuf;
else
srp_cmd->data_in_desc_cnt = numbuf;
}
if (cmd->sc_data_direction == DMA_TO_DEVICE)
srp_cmd->buf_fmt = fmt << 4;
else
srp_cmd->buf_fmt = fmt;
}
/**
* unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
* @cmd: srp_cmd whose additional_data member will be unmapped
* @dev: device for which the memory is mapped
*
*/
static void unmap_cmd_data(struct srp_cmd *cmd,
struct srp_event_struct *evt_struct,
struct device *dev)
{
u8 out_fmt, in_fmt;
out_fmt = cmd->buf_fmt >> 4;
in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
return;
if (evt_struct->cmnd)
scsi_dma_unmap(evt_struct->cmnd);
}
static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
struct srp_direct_buf *md)
{
int i;
struct scatterlist *sg;
u64 total_length = 0;
scsi_for_each_sg(cmd, sg, nseg, i) {
struct srp_direct_buf *descr = md + i;
descr->va = cpu_to_be64(sg_dma_address(sg));
descr->len = cpu_to_be32(sg_dma_len(sg));
descr->key = 0;
total_length += sg_dma_len(sg);
}
return total_length;
}
/**
* map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
* @cmd: Scsi_Cmnd with the scatterlist
* @srp_cmd: srp_cmd that contains the memory descriptor
* @dev: device for which to map dma memory
*
* Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
* Returns 1 on success.
*/
static int map_sg_data(struct scsi_cmnd *cmd,
struct srp_event_struct *evt_struct,
struct srp_cmd *srp_cmd, struct device *dev)
{
int sg_mapped;
u64 total_length = 0;
struct srp_direct_buf *data =
(struct srp_direct_buf *) srp_cmd->add_data;
struct srp_indirect_buf *indirect =
(struct srp_indirect_buf *) data;
sg_mapped = scsi_dma_map(cmd);
if (!sg_mapped)
return 1;
else if (sg_mapped < 0)
return 0;
set_srp_direction(cmd, srp_cmd, sg_mapped);
/* special case; we can use a single direct descriptor */
if (sg_mapped == 1) {
map_sg_list(cmd, sg_mapped, data);
return 1;
}
indirect->table_desc.va = 0;
indirect->table_desc.len = cpu_to_be32(sg_mapped *
sizeof(struct srp_direct_buf));
indirect->table_desc.key = 0;
if (sg_mapped <= MAX_INDIRECT_BUFS) {
total_length = map_sg_list(cmd, sg_mapped,
&indirect->desc_list[0]);
indirect->len = cpu_to_be32(total_length);
return 1;
}
/* get indirect table */
if (!evt_struct->ext_list) {
evt_struct->ext_list = (struct srp_direct_buf *)
dma_alloc_coherent(dev,
SG_ALL * sizeof(struct srp_direct_buf),
&evt_struct->ext_list_token, 0);
if (!evt_struct->ext_list) {
if (!firmware_has_feature(FW_FEATURE_CMO))
sdev_printk(KERN_ERR, cmd->device,
"Can't allocate memory "
"for indirect table\n");
scsi_dma_unmap(cmd);
return 0;
}
}
total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
indirect->len = cpu_to_be32(total_length);
indirect->table_desc.va = cpu_to_be64(evt_struct->ext_list_token);
indirect->table_desc.len = cpu_to_be32(sg_mapped *
sizeof(indirect->desc_list[0]));
memcpy(indirect->desc_list, evt_struct->ext_list,
MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
return 1;
}
/**
* map_data_for_srp_cmd: - Calls functions to map data for srp cmds
* @cmd: struct scsi_cmnd with the memory to be mapped
* @srp_cmd: srp_cmd that contains the memory descriptor
* @dev: dma device for which to map dma memory
*
* Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds
* Returns 1 on success.
*/
static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
struct srp_event_struct *evt_struct,
struct srp_cmd *srp_cmd, struct device *dev)
{
switch (cmd->sc_data_direction) {
case DMA_FROM_DEVICE:
case DMA_TO_DEVICE:
break;
case DMA_NONE:
return 1;
case DMA_BIDIRECTIONAL:
sdev_printk(KERN_ERR, cmd->device,
"Can't map DMA_BIDIRECTIONAL to read/write\n");
return 0;
default:
sdev_printk(KERN_ERR, cmd->device,
"Unknown data direction 0x%02x; can't map!\n",
cmd->sc_data_direction);
return 0;
}
return map_sg_data(cmd, evt_struct, srp_cmd, dev);
}
/**
* purge_requests: Our virtual adapter just shut down. purge any sent requests
* @hostdata: the adapter
*/
static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
{
struct srp_event_struct *evt;
unsigned long flags;
spin_lock_irqsave(hostdata->host->host_lock, flags);
while (!list_empty(&hostdata->sent)) {
evt = list_first_entry(&hostdata->sent, struct srp_event_struct, list);
list_del(&evt->list);
del_timer(&evt->timer);
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
if (evt->cmnd) {
evt->cmnd->result = (error_code << 16);
unmap_cmd_data(&evt->iu.srp.cmd, evt,
evt->hostdata->dev);
if (evt->cmnd_done)
evt->cmnd_done(evt->cmnd);
} else if (evt->done)
evt->done(evt);
free_event_struct(&evt->hostdata->pool, evt);
spin_lock_irqsave(hostdata->host->host_lock, flags);
}
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
}
/**
* ibmvscsi_reset_host - Reset the connection to the server
* @hostdata: struct ibmvscsi_host_data to reset
*/
static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
{
scsi_block_requests(hostdata->host);
atomic_set(&hostdata->request_limit, 0);
purge_requests(hostdata, DID_ERROR);
hostdata->reset_crq = 1;
wake_up(&hostdata->work_wait_q);
}
/**
* ibmvscsi_timeout - Internal command timeout handler
* @evt_struct: struct srp_event_struct that timed out
*
* Called when an internally generated command times out
*/
static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
{
struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
evt_struct->iu.srp.cmd.opcode);
ibmvscsi_reset_host(hostdata);
}
/* ------------------------------------------------------------
* Routines for sending and receiving SRPs
*/
/**
* ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
* @evt_struct: evt_struct to be sent
* @hostdata: ibmvscsi_host_data of host
* @timeout: timeout in seconds - 0 means do not time command
*
* Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
* Note that this routine assumes that host_lock is held for synchronization
*/
static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
struct ibmvscsi_host_data *hostdata,
unsigned long timeout)
{
__be64 *crq_as_u64 = (__be64 *)&evt_struct->crq;
int request_status = 0;
int rc;
int srp_req = 0;
/* If we have exhausted our request limit, just fail this request,
* unless it is for a reset or abort.
* Note that there are rare cases involving driver generated requests
* (such as task management requests) that the mid layer may think we
* can handle more requests (can_queue) when we actually can't
*/
if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
srp_req = 1;
request_status =
atomic_dec_if_positive(&hostdata->request_limit);
/* If request limit was -1 when we started, it is now even
* less than that
*/
if (request_status < -1)
goto send_error;
/* Otherwise, we may have run out of requests. */
/* If request limit was 0 when we started the adapter is in the
* process of performing a login with the server adapter, or
* we may have run out of requests.
*/
else if (request_status == -1 &&
evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
goto send_busy;
/* Abort and reset calls should make it through.
* Nothing except abort and reset should use the last two
* slots unless we had two or less to begin with.
*/
else if (request_status < 2 &&
evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
/* In the case that we have less than two requests
* available, check the server limit as a combination
* of the request limit and the number of requests
* in-flight (the size of the send list). If the
* server limit is greater than 2, return busy so
* that the last two are reserved for reset and abort.
*/
int server_limit = request_status;
struct srp_event_struct *tmp_evt;
list_for_each_entry(tmp_evt, &hostdata->sent, list) {
server_limit++;
}
if (server_limit > 2)
goto send_busy;
}
}
/* Copy the IU into the transfer area */
*evt_struct->xfer_iu = evt_struct->iu;
evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
/* Add this to the sent list. We need to do this
* before we actually send
* in case it comes back REALLY fast
*/
list_add_tail(&evt_struct->list, &hostdata->sent);
init_timer(&evt_struct->timer);
if (timeout) {
evt_struct->timer.data = (unsigned long) evt_struct;
evt_struct->timer.expires = jiffies + (timeout * HZ);
evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
add_timer(&evt_struct->timer);
}
rc = ibmvscsi_send_crq(hostdata, be64_to_cpu(crq_as_u64[0]),
be64_to_cpu(crq_as_u64[1]));
if (rc != 0) {
list_del(&evt_struct->list);
del_timer(&evt_struct->timer);
/* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
* Firmware will send a CRQ with a transport event (0xFF) to
* tell this client what has happened to the transport. This
* will be handled in ibmvscsi_handle_crq()
*/
if (rc == H_CLOSED) {
dev_warn(hostdata->dev, "send warning. "
"Receive queue closed, will retry.\n");
goto send_busy;
}
dev_err(hostdata->dev, "send error %d\n", rc);
if (srp_req)
atomic_inc(&hostdata->request_limit);
goto send_error;
}
return 0;
send_busy:
unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
free_event_struct(&hostdata->pool, evt_struct);
if (srp_req && request_status != -1)
atomic_inc(&hostdata->request_limit);
return SCSI_MLQUEUE_HOST_BUSY;
send_error:
unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
if (evt_struct->cmnd != NULL) {
evt_struct->cmnd->result = DID_ERROR << 16;
evt_struct->cmnd_done(evt_struct->cmnd);
} else if (evt_struct->done)
evt_struct->done(evt_struct);
free_event_struct(&hostdata->pool, evt_struct);
return 0;
}
/**
* handle_cmd_rsp: - Handle responses from commands
* @evt_struct: srp_event_struct to be handled
*
* Used as a callback by when sending scsi cmds.
* Gets called by ibmvscsi_handle_crq()
*/
static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
{
struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
struct scsi_cmnd *cmnd = evt_struct->cmnd;
if (unlikely(rsp->opcode != SRP_RSP)) {
if (printk_ratelimit())
dev_warn(evt_struct->hostdata->dev,
"bad SRP RSP type %d\n", rsp->opcode);
}
if (cmnd) {
cmnd->result |= rsp->status;
if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
memcpy(cmnd->sense_buffer,
rsp->data,
be32_to_cpu(rsp->sense_data_len));
unmap_cmd_data(&evt_struct->iu.srp.cmd,
evt_struct,
evt_struct->hostdata->dev);
if (rsp->flags & SRP_RSP_FLAG_DOOVER)
scsi_set_resid(cmnd,
be32_to_cpu(rsp->data_out_res_cnt));
else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
scsi_set_resid(cmnd, be32_to_cpu(rsp->data_in_res_cnt));
}
if (evt_struct->cmnd_done)
evt_struct->cmnd_done(cmnd);
}
/**
* lun_from_dev: - Returns the lun of the scsi device
* @dev: struct scsi_device
*
*/
static inline u16 lun_from_dev(struct scsi_device *dev)
{
return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
}
/**
* ibmvscsi_queue: - The queuecommand function of the scsi template
* @cmd: struct scsi_cmnd to be executed
* @done: Callback function to be called when cmd is completed
*/
static int ibmvscsi_queuecommand_lck(struct scsi_cmnd *cmnd,
void (*done) (struct scsi_cmnd *))
{
struct srp_cmd *srp_cmd;
struct srp_event_struct *evt_struct;
struct srp_indirect_buf *indirect;
struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
u16 lun = lun_from_dev(cmnd->device);
u8 out_fmt, in_fmt;
cmnd->result = (DID_OK << 16);
evt_struct = get_event_struct(&hostdata->pool);
if (!evt_struct)
return SCSI_MLQUEUE_HOST_BUSY;
/* Set up the actual SRP IU */
srp_cmd = &evt_struct->iu.srp.cmd;
memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
srp_cmd->opcode = SRP_CMD;
memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
srp_cmd->lun = cpu_to_be64(((u64)lun) << 48);
if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
if (!firmware_has_feature(FW_FEATURE_CMO))
sdev_printk(KERN_ERR, cmnd->device,
"couldn't convert cmd to srp_cmd\n");
free_event_struct(&hostdata->pool, evt_struct);
return SCSI_MLQUEUE_HOST_BUSY;
}
init_event_struct(evt_struct,
handle_cmd_rsp,
VIOSRP_SRP_FORMAT,
cmnd->request->timeout/HZ);
evt_struct->cmnd = cmnd;
evt_struct->cmnd_done = done;
/* Fix up dma address of the buffer itself */
indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
out_fmt = srp_cmd->buf_fmt >> 4;
in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
out_fmt == SRP_DATA_DESC_INDIRECT) &&
indirect->table_desc.va == 0) {
indirect->table_desc.va =
cpu_to_be64(be64_to_cpu(evt_struct->crq.IU_data_ptr) +
offsetof(struct srp_cmd, add_data) +
offsetof(struct srp_indirect_buf, desc_list));
}
return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
}
static DEF_SCSI_QCMD(ibmvscsi_queuecommand)
/* ------------------------------------------------------------
* Routines for driver initialization
*/
/**
* map_persist_bufs: - Pre-map persistent data for adapter logins
* @hostdata: ibmvscsi_host_data of host
*
* Map the capabilities and adapter info DMA buffers to avoid runtime failures.
* Return 1 on error, 0 on success.
*/
static int map_persist_bufs(struct ibmvscsi_host_data *hostdata)
{
hostdata->caps_addr = dma_map_single(hostdata->dev, &hostdata->caps,
sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
if (dma_mapping_error(hostdata->dev, hostdata->caps_addr)) {
dev_err(hostdata->dev, "Unable to map capabilities buffer!\n");
return 1;
}
hostdata->adapter_info_addr = dma_map_single(hostdata->dev,
&hostdata->madapter_info,
sizeof(hostdata->madapter_info),
DMA_BIDIRECTIONAL);
if (dma_mapping_error(hostdata->dev, hostdata->adapter_info_addr)) {
dev_err(hostdata->dev, "Unable to map adapter info buffer!\n");
dma_unmap_single(hostdata->dev, hostdata->caps_addr,
sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
return 1;
}
return 0;
}
/**
* unmap_persist_bufs: - Unmap persistent data needed for adapter logins
* @hostdata: ibmvscsi_host_data of host
*
* Unmap the capabilities and adapter info DMA buffers
*/
static void unmap_persist_bufs(struct ibmvscsi_host_data *hostdata)
{
dma_unmap_single(hostdata->dev, hostdata->caps_addr,
sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
dma_unmap_single(hostdata->dev, hostdata->adapter_info_addr,
sizeof(hostdata->madapter_info), DMA_BIDIRECTIONAL);
}
/**
* login_rsp: - Handle response to SRP login request
* @evt_struct: srp_event_struct with the response
*
* Used as a "done" callback by when sending srp_login. Gets called
* by ibmvscsi_handle_crq()
*/
static void login_rsp(struct srp_event_struct *evt_struct)
{
struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
case SRP_LOGIN_RSP: /* it worked! */
break;
case SRP_LOGIN_REJ: /* refused! */
dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
evt_struct->xfer_iu->srp.login_rej.reason);
/* Login failed. */
atomic_set(&hostdata->request_limit, -1);
return;
default:
dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
evt_struct->xfer_iu->srp.login_rsp.opcode);
/* Login failed. */
atomic_set(&hostdata->request_limit, -1);
return;
}
dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
hostdata->client_migrated = 0;
/* Now we know what the real request-limit is.
* This value is set rather than added to request_limit because
* request_limit could have been set to -1 by this client.
*/
atomic_set(&hostdata->request_limit,
be32_to_cpu(evt_struct->xfer_iu->srp.login_rsp.req_lim_delta));
/* If we had any pending I/Os, kick them */
scsi_unblock_requests(hostdata->host);
}
/**
* send_srp_login: - Sends the srp login
* @hostdata: ibmvscsi_host_data of host
*
* Returns zero if successful.
*/
static int send_srp_login(struct ibmvscsi_host_data *hostdata)
{
int rc;
unsigned long flags;
struct srp_login_req *login;
struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
BUG_ON(!evt_struct);
init_event_struct(evt_struct, login_rsp,
VIOSRP_SRP_FORMAT, login_timeout);
login = &evt_struct->iu.srp.login_req;
memset(login, 0, sizeof(*login));
login->opcode = SRP_LOGIN_REQ;
login->req_it_iu_len = cpu_to_be32(sizeof(union srp_iu));
login->req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
SRP_BUF_FORMAT_INDIRECT);
spin_lock_irqsave(hostdata->host->host_lock, flags);
/* Start out with a request limit of 0, since this is negotiated in
* the login request we are just sending and login requests always
* get sent by the driver regardless of request_limit.
*/
atomic_set(&hostdata->request_limit, 0);
rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
dev_info(hostdata->dev, "sent SRP login\n");
return rc;
};
/**
* capabilities_rsp: - Handle response to MAD adapter capabilities request
* @evt_struct: srp_event_struct with the response
*
* Used as a "done" callback by when sending adapter_info.
*/
static void capabilities_rsp(struct srp_event_struct *evt_struct)
{
struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
if (evt_struct->xfer_iu->mad.capabilities.common.status) {
dev_err(hostdata->dev, "error 0x%X getting capabilities info\n",
evt_struct->xfer_iu->mad.capabilities.common.status);
} else {
if (hostdata->caps.migration.common.server_support !=
cpu_to_be16(SERVER_SUPPORTS_CAP))
dev_info(hostdata->dev, "Partition migration not supported\n");
if (client_reserve) {
if (hostdata->caps.reserve.common.server_support ==
cpu_to_be16(SERVER_SUPPORTS_CAP))
dev_info(hostdata->dev, "Client reserve enabled\n");
else
dev_info(hostdata->dev, "Client reserve not supported\n");
}
}
send_srp_login(hostdata);
}
/**
* send_mad_capabilities: - Sends the mad capabilities request
* and stores the result so it can be retrieved with
* @hostdata: ibmvscsi_host_data of host
*/
static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
{
struct viosrp_capabilities *req;
struct srp_event_struct *evt_struct;
unsigned long flags;
struct device_node *of_node = hostdata->dev->of_node;
const char *location;
evt_struct = get_event_struct(&hostdata->pool);
BUG_ON(!evt_struct);
init_event_struct(evt_struct, capabilities_rsp,
VIOSRP_MAD_FORMAT, info_timeout);
req = &evt_struct->iu.mad.capabilities;
memset(req, 0, sizeof(*req));
hostdata->caps.flags = cpu_to_be32(CAP_LIST_SUPPORTED);
if (hostdata->client_migrated)
hostdata->caps.flags |= cpu_to_be32(CLIENT_MIGRATED);
strncpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
sizeof(hostdata->caps.name));
hostdata->caps.name[sizeof(hostdata->caps.name) - 1] = '\0';
location = of_get_property(of_node, "ibm,loc-code", NULL);
location = location ? location : dev_name(hostdata->dev);
strncpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
hostdata->caps.loc[sizeof(hostdata->caps.loc) - 1] = '\0';
req->common.type = cpu_to_be32(VIOSRP_CAPABILITIES_TYPE);
req->buffer = cpu_to_be64(hostdata->caps_addr);
hostdata->caps.migration.common.cap_type =
cpu_to_be32(MIGRATION_CAPABILITIES);
hostdata->caps.migration.common.length =
cpu_to_be16(sizeof(hostdata->caps.migration));
hostdata->caps.migration.common.server_support =
cpu_to_be16(SERVER_SUPPORTS_CAP);
hostdata->caps.migration.ecl = cpu_to_be32(1);
if (client_reserve) {
hostdata->caps.reserve.common.cap_type =
cpu_to_be32(RESERVATION_CAPABILITIES);
hostdata->caps.reserve.common.length =
cpu_to_be16(sizeof(hostdata->caps.reserve));
hostdata->caps.reserve.common.server_support =
cpu_to_be16(SERVER_SUPPORTS_CAP);
hostdata->caps.reserve.type =
cpu_to_be32(CLIENT_RESERVE_SCSI_2);
req->common.length =
cpu_to_be16(sizeof(hostdata->caps));
} else
req->common.length = cpu_to_be16(sizeof(hostdata->caps) -
sizeof(hostdata->caps.reserve));
spin_lock_irqsave(hostdata->host->host_lock, flags);
if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
dev_err(hostdata->dev, "couldn't send CAPABILITIES_REQ!\n");
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
};
/**
* fast_fail_rsp: - Handle response to MAD enable fast fail
* @evt_struct: srp_event_struct with the response
*
* Used as a "done" callback by when sending enable fast fail. Gets called
* by ibmvscsi_handle_crq()
*/
static void fast_fail_rsp(struct srp_event_struct *evt_struct)
{
struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
u16 status = be16_to_cpu(evt_struct->xfer_iu->mad.fast_fail.common.status);
if (status == VIOSRP_MAD_NOT_SUPPORTED)
dev_err(hostdata->dev, "fast_fail not supported in server\n");
else if (status == VIOSRP_MAD_FAILED)
dev_err(hostdata->dev, "fast_fail request failed\n");
else if (status != VIOSRP_MAD_SUCCESS)
dev_err(hostdata->dev, "error 0x%X enabling fast_fail\n", status);
send_mad_capabilities(hostdata);
}
/**
* init_host - Start host initialization
* @hostdata: ibmvscsi_host_data of host
*
* Returns zero if successful.
*/
static int enable_fast_fail(struct ibmvscsi_host_data *hostdata)
{
int rc;
unsigned long flags;
struct viosrp_fast_fail *fast_fail_mad;
struct srp_event_struct *evt_struct;
if (!fast_fail) {
send_mad_capabilities(hostdata);
return 0;
}
evt_struct = get_event_struct(&hostdata->pool);
BUG_ON(!evt_struct);
init_event_struct(evt_struct, fast_fail_rsp, VIOSRP_MAD_FORMAT, info_timeout);
fast_fail_mad = &evt_struct->iu.mad.fast_fail;
memset(fast_fail_mad, 0, sizeof(*fast_fail_mad));
fast_fail_mad->common.type = cpu_to_be32(VIOSRP_ENABLE_FAST_FAIL);
fast_fail_mad->common.length = cpu_to_be16(sizeof(*fast_fail_mad));
spin_lock_irqsave(hostdata->host->host_lock, flags);
rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
return rc;
}
/**
* adapter_info_rsp: - Handle response to MAD adapter info request
* @evt_struct: srp_event_struct with the response
*
* Used as a "done" callback by when sending adapter_info. Gets called
* by ibmvscsi_handle_crq()
*/
static void adapter_info_rsp(struct srp_event_struct *evt_struct)
{
struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
dev_err(hostdata->dev, "error %d getting adapter info\n",
evt_struct->xfer_iu->mad.adapter_info.common.status);
} else {
dev_info(hostdata->dev, "host srp version: %s, "
"host partition %s (%d), OS %d, max io %u\n",
hostdata->madapter_info.srp_version,
hostdata->madapter_info.partition_name,
be32_to_cpu(hostdata->madapter_info.partition_number),
be32_to_cpu(hostdata->madapter_info.os_type),
be32_to_cpu(hostdata->madapter_info.port_max_txu[0]));
if (hostdata->madapter_info.port_max_txu[0])
hostdata->host->max_sectors =
be32_to_cpu(hostdata->madapter_info.port_max_txu[0]) >> 9;
if (be32_to_cpu(hostdata->madapter_info.os_type) == 3 &&
strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
hostdata->madapter_info.srp_version);
dev_err(hostdata->dev, "limiting scatterlists to %d\n",
MAX_INDIRECT_BUFS);
hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
}
if (be32_to_cpu(hostdata->madapter_info.os_type) == 3) {
enable_fast_fail(hostdata);
return;
}
}
send_srp_login(hostdata);
}
/**
* send_mad_adapter_info: - Sends the mad adapter info request
* and stores the result so it can be retrieved with
* sysfs. We COULD consider causing a failure if the
* returned SRP version doesn't match ours.
* @hostdata: ibmvscsi_host_data of host
*
* Returns zero if successful.
*/
static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
{
struct viosrp_adapter_info *req;
struct srp_event_struct *evt_struct;
unsigned long flags;
evt_struct = get_event_struct(&hostdata->pool);
BUG_ON(!evt_struct);
init_event_struct(evt_struct,
adapter_info_rsp,
VIOSRP_MAD_FORMAT,
info_timeout);
req = &evt_struct->iu.mad.adapter_info;
memset(req, 0x00, sizeof(*req));
req->common.type = cpu_to_be32(VIOSRP_ADAPTER_INFO_TYPE);
req->common.length = cpu_to_be16(sizeof(hostdata->madapter_info));
req->buffer = cpu_to_be64(hostdata->adapter_info_addr);
spin_lock_irqsave(hostdata->host->host_lock, flags);
if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
};
/**
* init_adapter: Start virtual adapter initialization sequence
*
*/
static void init_adapter(struct ibmvscsi_host_data *hostdata)
{
send_mad_adapter_info(hostdata);
}
/**
* sync_completion: Signal that a synchronous command has completed
* Note that after returning from this call, the evt_struct is freed.
* the caller waiting on this completion shouldn't touch the evt_struct
* again.
*/
static void sync_completion(struct srp_event_struct *evt_struct)
{
/* copy the response back */
if (evt_struct->sync_srp)
*evt_struct->sync_srp = *evt_struct->xfer_iu;
complete(&evt_struct->comp);
}
/**
* ibmvscsi_abort: Abort a command...from scsi host template
* send this over to the server and wait synchronously for the response
*/
static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
{
struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
struct srp_tsk_mgmt *tsk_mgmt;
struct srp_event_struct *evt;
struct srp_event_struct *tmp_evt, *found_evt;
union viosrp_iu srp_rsp;
int rsp_rc;
unsigned long flags;
u16 lun = lun_from_dev(cmd->device);
unsigned long wait_switch = 0;
/* First, find this command in our sent list so we can figure
* out the correct tag
*/
spin_lock_irqsave(hostdata->host->host_lock, flags);
wait_switch = jiffies + (init_timeout * HZ);
do {
found_evt = NULL;
list_for_each_entry(tmp_evt, &hostdata->sent, list) {
if (tmp_evt->cmnd == cmd) {
found_evt = tmp_evt;
break;
}
}
if (!found_evt) {
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
return SUCCESS;
}
evt = get_event_struct(&hostdata->pool);
if (evt == NULL) {
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
sdev_printk(KERN_ERR, cmd->device,
"failed to allocate abort event\n");
return FAILED;
}
init_event_struct(evt,
sync_completion,
VIOSRP_SRP_FORMAT,
abort_timeout);
tsk_mgmt = &evt->iu.srp.tsk_mgmt;
/* Set up an abort SRP command */
memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
tsk_mgmt->opcode = SRP_TSK_MGMT;
tsk_mgmt->lun = cpu_to_be64(((u64) lun) << 48);
tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
tsk_mgmt->task_tag = (u64) found_evt;
evt->sync_srp = &srp_rsp;
init_completion(&evt->comp);
rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
break;
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
msleep(10);
spin_lock_irqsave(hostdata->host->host_lock, flags);
} while (time_before(jiffies, wait_switch));
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
if (rsp_rc != 0) {
sdev_printk(KERN_ERR, cmd->device,
"failed to send abort() event. rc=%d\n", rsp_rc);
return FAILED;
}
sdev_printk(KERN_INFO, cmd->device,
"aborting command. lun 0x%llx, tag 0x%llx\n",
(((u64) lun) << 48), (u64) found_evt);
wait_for_completion(&evt->comp);
/* make sure we got a good response */
if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
if (printk_ratelimit())
sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
srp_rsp.srp.rsp.opcode);
return FAILED;
}
if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
rsp_rc = *((int *)srp_rsp.srp.rsp.data);
else
rsp_rc = srp_rsp.srp.rsp.status;
if (rsp_rc) {
if (printk_ratelimit())
sdev_printk(KERN_WARNING, cmd->device,
"abort code %d for task tag 0x%llx\n",
rsp_rc, tsk_mgmt->task_tag);
return FAILED;
}
/* Because we dropped the spinlock above, it's possible
* The event is no longer in our list. Make sure it didn't
* complete while we were aborting
*/
spin_lock_irqsave(hostdata->host->host_lock, flags);
found_evt = NULL;
list_for_each_entry(tmp_evt, &hostdata->sent, list) {
if (tmp_evt->cmnd == cmd) {
found_evt = tmp_evt;
break;
}
}
if (found_evt == NULL) {
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
tsk_mgmt->task_tag);
return SUCCESS;
}
sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
tsk_mgmt->task_tag);
cmd->result = (DID_ABORT << 16);
list_del(&found_evt->list);
unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
found_evt->hostdata->dev);
free_event_struct(&found_evt->hostdata->pool, found_evt);
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
atomic_inc(&hostdata->request_limit);
return SUCCESS;
}
/**
* ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
* template send this over to the server and wait synchronously for the
* response
*/
static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
{
struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
struct srp_tsk_mgmt *tsk_mgmt;
struct srp_event_struct *evt;
struct srp_event_struct *tmp_evt, *pos;
union viosrp_iu srp_rsp;
int rsp_rc;
unsigned long flags;
u16 lun = lun_from_dev(cmd->device);
unsigned long wait_switch = 0;
spin_lock_irqsave(hostdata->host->host_lock, flags);
wait_switch = jiffies + (init_timeout * HZ);
do {
evt = get_event_struct(&hostdata->pool);
if (evt == NULL) {
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
sdev_printk(KERN_ERR, cmd->device,
"failed to allocate reset event\n");
return FAILED;
}
init_event_struct(evt,
sync_completion,
VIOSRP_SRP_FORMAT,
reset_timeout);
tsk_mgmt = &evt->iu.srp.tsk_mgmt;
/* Set up a lun reset SRP command */
memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
tsk_mgmt->opcode = SRP_TSK_MGMT;
tsk_mgmt->lun = cpu_to_be64(((u64) lun) << 48);
tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
evt->sync_srp = &srp_rsp;
init_completion(&evt->comp);
rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
break;
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
msleep(10);
spin_lock_irqsave(hostdata->host->host_lock, flags);
} while (time_before(jiffies, wait_switch));
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
if (rsp_rc != 0) {
sdev_printk(KERN_ERR, cmd->device,
"failed to send reset event. rc=%d\n", rsp_rc);
return FAILED;
}
sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
(((u64) lun) << 48));
wait_for_completion(&evt->comp);
/* make sure we got a good response */
if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
if (printk_ratelimit())
sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
srp_rsp.srp.rsp.opcode);
return FAILED;
}
if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
rsp_rc = *((int *)srp_rsp.srp.rsp.data);
else
rsp_rc = srp_rsp.srp.rsp.status;
if (rsp_rc) {
if (printk_ratelimit())
sdev_printk(KERN_WARNING, cmd->device,
"reset code %d for task tag 0x%llx\n",
rsp_rc, tsk_mgmt->task_tag);
return FAILED;
}
/* We need to find all commands for this LUN that have not yet been
* responded to, and fail them with DID_RESET
*/
spin_lock_irqsave(hostdata->host->host_lock, flags);
list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
if (tmp_evt->cmnd)
tmp_evt->cmnd->result = (DID_RESET << 16);
list_del(&tmp_evt->list);
unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
tmp_evt->hostdata->dev);
free_event_struct(&tmp_evt->hostdata->pool,
tmp_evt);
atomic_inc(&hostdata->request_limit);
if (tmp_evt->cmnd_done)
tmp_evt->cmnd_done(tmp_evt->cmnd);
else if (tmp_evt->done)
tmp_evt->done(tmp_evt);
}
}
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
return SUCCESS;
}
/**
* ibmvscsi_eh_host_reset_handler - Reset the connection to the server
* @cmd: struct scsi_cmnd having problems
*/
static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
{
unsigned long wait_switch = 0;
struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
ibmvscsi_reset_host(hostdata);
for (wait_switch = jiffies + (init_timeout * HZ);
time_before(jiffies, wait_switch) &&
atomic_read(&hostdata->request_limit) < 2;) {
msleep(10);
}
if (atomic_read(&hostdata->request_limit) <= 0)
return FAILED;
return SUCCESS;
}
/**
* ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
* @crq: Command/Response queue
* @hostdata: ibmvscsi_host_data of host
*
*/
static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
struct ibmvscsi_host_data *hostdata)
{
long rc;
unsigned long flags;
/* The hypervisor copies our tag value here so no byteswapping */
struct srp_event_struct *evt_struct =
(__force struct srp_event_struct *)crq->IU_data_ptr;
switch (crq->valid) {
case 0xC0: /* initialization */
switch (crq->format) {
case 0x01: /* Initialization message */
dev_info(hostdata->dev, "partner initialized\n");
/* Send back a response */
rc = ibmvscsi_send_crq(hostdata, 0xC002000000000000LL, 0);
if (rc == 0) {
/* Now login */
init_adapter(hostdata);
} else {
dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
}
break;
case 0x02: /* Initialization response */
dev_info(hostdata->dev, "partner initialization complete\n");
/* Now login */
init_adapter(hostdata);
break;
default:
dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
}
return;
case 0xFF: /* Hypervisor telling us the connection is closed */
scsi_block_requests(hostdata->host);
atomic_set(&hostdata->request_limit, 0);
if (crq->format == 0x06) {
/* We need to re-setup the interpartition connection */
dev_info(hostdata->dev, "Re-enabling adapter!\n");
hostdata->client_migrated = 1;
hostdata->reenable_crq = 1;
purge_requests(hostdata, DID_REQUEUE);
wake_up(&hostdata->work_wait_q);
} else {
dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
crq->format);
ibmvscsi_reset_host(hostdata);
}
return;
case 0x80: /* real payload */
break;
default:
dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
crq->valid);
return;
}
/* The only kind of payload CRQs we should get are responses to
* things we send. Make sure this response is to something we
* actually sent
*/
if (!valid_event_struct(&hostdata->pool, evt_struct)) {
dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
evt_struct);
return;
}
if (atomic_read(&evt_struct->free)) {
dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
evt_struct);
return;
}
if (crq->format == VIOSRP_SRP_FORMAT)
atomic_add(be32_to_cpu(evt_struct->xfer_iu->srp.rsp.req_lim_delta),
&hostdata->request_limit);
del_timer(&evt_struct->timer);
if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
evt_struct->cmnd->result = DID_ERROR << 16;
if (evt_struct->done)
evt_struct->done(evt_struct);
else
dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
/*
* Lock the host_lock before messing with these structures, since we
* are running in a task context
*/
spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
list_del(&evt_struct->list);
free_event_struct(&evt_struct->hostdata->pool, evt_struct);
spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
}
/**
* ibmvscsi_get_host_config: Send the command to the server to get host
* configuration data. The data is opaque to us.
*/
static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
unsigned char *buffer, int length)
{
struct viosrp_host_config *host_config;
struct srp_event_struct *evt_struct;
unsigned long flags;
dma_addr_t addr;
int rc;
evt_struct = get_event_struct(&hostdata->pool);
if (!evt_struct) {
dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
return -1;
}
init_event_struct(evt_struct,
sync_completion,
VIOSRP_MAD_FORMAT,
info_timeout);
host_config = &evt_struct->iu.mad.host_config;
/* The transport length field is only 16-bit */
length = min(0xffff, length);
/* Set up a lun reset SRP command */
memset(host_config, 0x00, sizeof(*host_config));
host_config->common.type = cpu_to_be32(VIOSRP_HOST_CONFIG_TYPE);
host_config->common.length = cpu_to_be16(length);
addr = dma_map_single(hostdata->dev, buffer, length, DMA_BIDIRECTIONAL);
if (dma_mapping_error(hostdata->dev, addr)) {
if (!firmware_has_feature(FW_FEATURE_CMO))
dev_err(hostdata->dev,
"dma_mapping error getting host config\n");
free_event_struct(&hostdata->pool, evt_struct);
return -1;
}
host_config->buffer = cpu_to_be64(addr);
init_completion(&evt_struct->comp);
spin_lock_irqsave(hostdata->host->host_lock, flags);
rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
spin_unlock_irqrestore(hostdata->host->host_lock, flags);
if (rc == 0)
wait_for_completion(&evt_struct->comp);
dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
return rc;
}
/**
* ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
* @sdev: struct scsi_device device to configure
*
* Enable allow_restart for a device if it is a disk. Adjust the
* queue_depth here also as is required by the documentation for
* struct scsi_host_template.
*/
static int ibmvscsi_slave_configure(struct scsi_device *sdev)
{
struct Scsi_Host *shost = sdev->host;
unsigned long lock_flags = 0;
spin_lock_irqsave(shost->host_lock, lock_flags);
if (sdev->type == TYPE_DISK) {
sdev->allow_restart = 1;
blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
}
spin_unlock_irqrestore(shost->host_lock, lock_flags);
scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
return 0;
}
/**
* ibmvscsi_change_queue_depth - Change the device's queue depth
* @sdev: scsi device struct
* @qdepth: depth to set
* @reason: calling context
*
* Return value:
* actual depth set
**/
static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth,
int reason)
{
if (reason != SCSI_QDEPTH_DEFAULT)
return -EOPNOTSUPP;
if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
scsi_adjust_queue_depth(sdev, 0, qdepth);
return sdev->queue_depth;
}
/* ------------------------------------------------------------
* sysfs attributes
*/
static ssize_t show_host_vhost_loc(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
int len;
len = snprintf(buf, sizeof(hostdata->caps.loc), "%s\n",
hostdata->caps.loc);
return len;
}
static struct device_attribute ibmvscsi_host_vhost_loc = {
.attr = {
.name = "vhost_loc",
.mode = S_IRUGO,
},
.show = show_host_vhost_loc,
};
static ssize_t show_host_vhost_name(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
int len;
len = snprintf(buf, sizeof(hostdata->caps.name), "%s\n",
hostdata->caps.name);
return len;
}
static struct device_attribute ibmvscsi_host_vhost_name = {
.attr = {
.name = "vhost_name",
.mode = S_IRUGO,
},
.show = show_host_vhost_name,
};
static ssize_t show_host_srp_version(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
int len;
len = snprintf(buf, PAGE_SIZE, "%s\n",
hostdata->madapter_info.srp_version);
return len;
}
static struct device_attribute ibmvscsi_host_srp_version = {
.attr = {
.name = "srp_version",
.mode = S_IRUGO,
},
.show = show_host_srp_version,
};
static ssize_t show_host_partition_name(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
int len;
len = snprintf(buf, PAGE_SIZE, "%s\n",
hostdata->madapter_info.partition_name);
return len;
}
static struct device_attribute ibmvscsi_host_partition_name = {
.attr = {
.name = "partition_name",
.mode = S_IRUGO,
},
.show = show_host_partition_name,
};
static ssize_t show_host_partition_number(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
int len;
len = snprintf(buf, PAGE_SIZE, "%d\n",
hostdata->madapter_info.partition_number);
return len;
}
static struct device_attribute ibmvscsi_host_partition_number = {
.attr = {
.name = "partition_number",
.mode = S_IRUGO,
},
.show = show_host_partition_number,
};
static ssize_t show_host_mad_version(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
int len;
len = snprintf(buf, PAGE_SIZE, "%d\n",
hostdata->madapter_info.mad_version);
return len;
}
static struct device_attribute ibmvscsi_host_mad_version = {
.attr = {
.name = "mad_version",
.mode = S_IRUGO,
},
.show = show_host_mad_version,
};
static ssize_t show_host_os_type(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
int len;
len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
return len;
}
static struct device_attribute ibmvscsi_host_os_type = {
.attr = {
.name = "os_type",
.mode = S_IRUGO,
},
.show = show_host_os_type,
};
static ssize_t show_host_config(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
struct ibmvscsi_host_data *hostdata = shost_priv(shost);
/* returns null-terminated host config data */
if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
return strlen(buf);
else
return 0;
}
static struct device_attribute ibmvscsi_host_config = {
.attr = {
.name = "config",
.mode = S_IRUGO,
},
.show = show_host_config,
};
static struct device_attribute *ibmvscsi_attrs[] = {
&ibmvscsi_host_vhost_loc,
&ibmvscsi_host_vhost_name,
&ibmvscsi_host_srp_version,
&ibmvscsi_host_partition_name,
&ibmvscsi_host_partition_number,
&ibmvscsi_host_mad_version,
&ibmvscsi_host_os_type,
&ibmvscsi_host_config,
NULL
};
/* ------------------------------------------------------------
* SCSI driver registration
*/
static struct scsi_host_template driver_template = {
.module = THIS_MODULE,
.name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
.proc_name = "ibmvscsi",
.queuecommand = ibmvscsi_queuecommand,
.eh_abort_handler = ibmvscsi_eh_abort_handler,
.eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
.eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
.slave_configure = ibmvscsi_slave_configure,
.change_queue_depth = ibmvscsi_change_queue_depth,
.cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
.can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
.this_id = -1,
.sg_tablesize = SG_ALL,
.use_clustering = ENABLE_CLUSTERING,
.shost_attrs = ibmvscsi_attrs,
};
/**
* ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
*
* @vdev: struct vio_dev for the device whose desired IO mem is to be returned
*
* Return value:
* Number of bytes of IO data the driver will need to perform well.
*/
static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
{
/* iu_storage data allocated in initialize_event_pool */
unsigned long desired_io = max_events * sizeof(union viosrp_iu);
/* add io space for sg data */
desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
IBMVSCSI_CMDS_PER_LUN_DEFAULT);
return desired_io;
}
static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata)
{
int rc;
char *action = "reset";
if (hostdata->reset_crq) {
smp_rmb();
hostdata->reset_crq = 0;
rc = ibmvscsi_reset_crq_queue(&hostdata->queue, hostdata);
if (!rc)
rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0);
vio_enable_interrupts(to_vio_dev(hostdata->dev));
} else if (hostdata->reenable_crq) {
smp_rmb();
action = "enable";
rc = ibmvscsi_reenable_crq_queue(&hostdata->queue, hostdata);
hostdata->reenable_crq = 0;
if (!rc)
rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0);
} else
return;
if (rc) {
atomic_set(&hostdata->request_limit, -1);
dev_err(hostdata->dev, "error after %s\n", action);
}
scsi_unblock_requests(hostdata->host);
}
static int ibmvscsi_work_to_do(struct ibmvscsi_host_data *hostdata)
{
if (kthread_should_stop())
return 1;
else if (hostdata->reset_crq) {
smp_rmb();
return 1;
} else if (hostdata->reenable_crq) {
smp_rmb();
return 1;
}
return 0;
}
static int ibmvscsi_work(void *data)
{
struct ibmvscsi_host_data *hostdata = data;
int rc;
set_user_nice(current, -20);
while (1) {
rc = wait_event_interruptible(hostdata->work_wait_q,
ibmvscsi_work_to_do(hostdata));
BUG_ON(rc);
if (kthread_should_stop())
break;
ibmvscsi_do_work(hostdata);
}
return 0;
}
/**
* Called by bus code for each adapter
*/
static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
{
struct ibmvscsi_host_data *hostdata;
struct Scsi_Host *host;
struct device *dev = &vdev->dev;
struct srp_rport_identifiers ids;
struct srp_rport *rport;
unsigned long wait_switch = 0;
int rc;
dev_set_drvdata(&vdev->dev, NULL);
host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
if (!host) {
dev_err(&vdev->dev, "couldn't allocate host data\n");
goto scsi_host_alloc_failed;
}
host->transportt = ibmvscsi_transport_template;
hostdata = shost_priv(host);
memset(hostdata, 0x00, sizeof(*hostdata));
INIT_LIST_HEAD(&hostdata->sent);
init_waitqueue_head(&hostdata->work_wait_q);
hostdata->host = host;
hostdata->dev = dev;
atomic_set(&hostdata->request_limit, -1);
hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
if (map_persist_bufs(hostdata)) {
dev_err(&vdev->dev, "couldn't map persistent buffers\n");
goto persist_bufs_failed;
}
hostdata->work_thread = kthread_run(ibmvscsi_work, hostdata, "%s_%d",
"ibmvscsi", host->host_no);
if (IS_ERR(hostdata->work_thread)) {
dev_err(&vdev->dev, "couldn't initialize kthread. rc=%ld\n",
PTR_ERR(hostdata->work_thread));
goto init_crq_failed;
}
rc = ibmvscsi_init_crq_queue(&hostdata->queue, hostdata, max_events);
if (rc != 0 && rc != H_RESOURCE) {
dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
goto kill_kthread;
}
if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
dev_err(&vdev->dev, "couldn't initialize event pool\n");
goto init_pool_failed;
}
host->max_lun = 8;
host->max_id = max_id;
host->max_channel = max_channel;
host->max_cmd_len = 16;
if (scsi_add_host(hostdata->host, hostdata->dev))
goto add_host_failed;
/* we don't have a proper target_port_id so let's use the fake one */
memcpy(ids.port_id, hostdata->madapter_info.partition_name,
sizeof(ids.port_id));
ids.roles = SRP_RPORT_ROLE_TARGET;
rport = srp_rport_add(host, &ids);
if (IS_ERR(rport))
goto add_srp_port_failed;
/* Try to send an initialization message. Note that this is allowed
* to fail if the other end is not acive. In that case we don't
* want to scan
*/
if (ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0) == 0
|| rc == H_RESOURCE) {
/*
* Wait around max init_timeout secs for the adapter to finish
* initializing. When we are done initializing, we will have a
* valid request_limit. We don't want Linux scanning before
* we are ready.
*/
for (wait_switch = jiffies + (init_timeout * HZ);
time_before(jiffies, wait_switch) &&
atomic_read(&hostdata->request_limit) < 2;) {
msleep(10);
}
/* if we now have a valid request_limit, initiate a scan */
if (atomic_read(&hostdata->request_limit) > 0)
scsi_scan_host(host);
}
dev_set_drvdata(&vdev->dev, hostdata);
return 0;
add_srp_port_failed:
scsi_remove_host(hostdata->host);
add_host_failed:
release_event_pool(&hostdata->pool, hostdata);
init_pool_failed:
ibmvscsi_release_crq_queue(&hostdata->queue, hostdata, max_events);
kill_kthread:
kthread_stop(hostdata->work_thread);
init_crq_failed:
unmap_persist_bufs(hostdata);
persist_bufs_failed:
scsi_host_put(host);
scsi_host_alloc_failed:
return -1;
}
static int ibmvscsi_remove(struct vio_dev *vdev)
{
struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
unmap_persist_bufs(hostdata);
release_event_pool(&hostdata->pool, hostdata);
ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,
max_events);
kthread_stop(hostdata->work_thread);
srp_remove_host(hostdata->host);
scsi_remove_host(hostdata->host);
scsi_host_put(hostdata->host);
return 0;
}
/**
* ibmvscsi_resume: Resume from suspend
* @dev: device struct
*
* We may have lost an interrupt across suspend/resume, so kick the
* interrupt handler
*/
static int ibmvscsi_resume(struct device *dev)
{
struct ibmvscsi_host_data *hostdata = dev_get_drvdata(dev);
vio_disable_interrupts(to_vio_dev(hostdata->dev));
tasklet_schedule(&hostdata->srp_task);
return 0;
}
/**
* ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
* support.
*/
static struct vio_device_id ibmvscsi_device_table[] = {
{"vscsi", "IBM,v-scsi"},
{ "", "" }
};
MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
static struct dev_pm_ops ibmvscsi_pm_ops = {
.resume = ibmvscsi_resume
};
static struct vio_driver ibmvscsi_driver = {
.id_table = ibmvscsi_device_table,
.probe = ibmvscsi_probe,
.remove = ibmvscsi_remove,
.get_desired_dma = ibmvscsi_get_desired_dma,
.name = "ibmvscsi",
.pm = &ibmvscsi_pm_ops,
};
static struct srp_function_template ibmvscsi_transport_functions = {
};
int __init ibmvscsi_module_init(void)
{
int ret;
/* Ensure we have two requests to do error recovery */
driver_template.can_queue = max_requests;
max_events = max_requests + 2;
if (!firmware_has_feature(FW_FEATURE_VIO))
return -ENODEV;
ibmvscsi_transport_template =
srp_attach_transport(&ibmvscsi_transport_functions);
if (!ibmvscsi_transport_template)
return -ENOMEM;
ret = vio_register_driver(&ibmvscsi_driver);
if (ret)
srp_release_transport(ibmvscsi_transport_template);
return ret;
}
void __exit ibmvscsi_module_exit(void)
{
vio_unregister_driver(&ibmvscsi_driver);
srp_release_transport(ibmvscsi_transport_template);
}
module_init(ibmvscsi_module_init);
module_exit(ibmvscsi_module_exit);