linux/drivers/s390/scsi/zfcp_qdio.c
Heiko Carstens a53c8fab3f s390/comments: unify copyright messages and remove file names
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 11:15:04 +02:00

512 lines
14 KiB
C

/*
* zfcp device driver
*
* Setup and helper functions to access QDIO.
*
* Copyright IBM Corp. 2002, 2010
*/
#define KMSG_COMPONENT "zfcp"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/slab.h>
#include <linux/module.h>
#include "zfcp_ext.h"
#include "zfcp_qdio.h"
#define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer))
static bool enable_multibuffer;
module_param_named(datarouter, enable_multibuffer, bool, 0400);
MODULE_PARM_DESC(datarouter, "Enable hardware data router support");
static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal)
{
int pos;
for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) {
sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL);
if (!sbal[pos])
return -ENOMEM;
}
for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++)
if (pos % QBUFF_PER_PAGE)
sbal[pos] = sbal[pos - 1] + 1;
return 0;
}
static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id,
unsigned int qdio_err)
{
struct zfcp_adapter *adapter = qdio->adapter;
dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
if (qdio_err & QDIO_ERROR_SLSB_STATE) {
zfcp_qdio_siosl(adapter);
zfcp_erp_adapter_shutdown(adapter, 0, id);
return;
}
zfcp_erp_adapter_reopen(adapter,
ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
ZFCP_STATUS_COMMON_ERP_FAILED, id);
}
static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
{
int i, sbal_idx;
for (i = first; i < first + cnt; i++) {
sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
}
}
/* this needs to be called prior to updating the queue fill level */
static inline void zfcp_qdio_account(struct zfcp_qdio *qdio)
{
unsigned long long now, span;
int used;
now = get_clock_monotonic();
span = (now - qdio->req_q_time) >> 12;
used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free);
qdio->req_q_util += used * span;
qdio->req_q_time = now;
}
static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
int queue_no, int idx, int count,
unsigned long parm)
{
struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
if (unlikely(qdio_err)) {
zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err);
return;
}
/* cleanup all SBALs being program-owned now */
zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
spin_lock_irq(&qdio->stat_lock);
zfcp_qdio_account(qdio);
spin_unlock_irq(&qdio->stat_lock);
atomic_add(count, &qdio->req_q_free);
wake_up(&qdio->req_q_wq);
}
static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
int queue_no, int idx, int count,
unsigned long parm)
{
struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
struct zfcp_adapter *adapter = qdio->adapter;
struct qdio_buffer_element *sbale;
int sbal_no, sbal_idx;
void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1];
u64 req_id;
u8 scount;
if (unlikely(qdio_err)) {
memset(pl, 0, ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *));
if (zfcp_adapter_multi_buffer_active(adapter)) {
sbale = qdio->res_q[idx]->element;
req_id = (u64) sbale->addr;
scount = sbale->scount + 1; /* incl. signaling SBAL */
for (sbal_no = 0; sbal_no < scount; sbal_no++) {
sbal_idx = (idx + sbal_no) %
QDIO_MAX_BUFFERS_PER_Q;
pl[sbal_no] = qdio->res_q[sbal_idx];
}
zfcp_dbf_hba_def_err(adapter, req_id, scount, pl);
}
zfcp_qdio_handler_error(qdio, "qdires1", qdio_err);
return;
}
/*
* go through all SBALs from input queue currently
* returned by QDIO layer
*/
for (sbal_no = 0; sbal_no < count; sbal_no++) {
sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
/* go through all SBALEs of SBAL */
zfcp_fsf_reqid_check(qdio, sbal_idx);
}
/*
* put SBALs back to response queue
*/
if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count))
zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2");
}
static struct qdio_buffer_element *
zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
struct qdio_buffer_element *sbale;
/* set last entry flag in current SBALE of current SBAL */
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;
/* don't exceed last allowed SBAL */
if (q_req->sbal_last == q_req->sbal_limit)
return NULL;
/* set chaining flag in first SBALE of current SBAL */
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS;
/* calculate index of next SBAL */
q_req->sbal_last++;
q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
/* keep this requests number of SBALs up-to-date */
q_req->sbal_number++;
BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ);
/* start at first SBALE of new SBAL */
q_req->sbale_curr = 0;
/* set storage-block type for new SBAL */
sbale = zfcp_qdio_sbale_curr(qdio, q_req);
sbale->sflags |= q_req->sbtype;
return sbale;
}
static struct qdio_buffer_element *
zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1)
return zfcp_qdio_sbal_chain(qdio, q_req);
q_req->sbale_curr++;
return zfcp_qdio_sbale_curr(qdio, q_req);
}
/**
* zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
* @qdio: pointer to struct zfcp_qdio
* @q_req: pointer to struct zfcp_qdio_req
* @sg: scatter-gather list
* @max_sbals: upper bound for number of SBALs to be used
* Returns: zero or -EINVAL on error
*/
int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
struct scatterlist *sg)
{
struct qdio_buffer_element *sbale;
/* set storage-block type for this request */
sbale = zfcp_qdio_sbale_req(qdio, q_req);
sbale->sflags |= q_req->sbtype;
for (; sg; sg = sg_next(sg)) {
sbale = zfcp_qdio_sbale_next(qdio, q_req);
if (!sbale) {
atomic_inc(&qdio->req_q_full);
zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
q_req->sbal_number);
return -EINVAL;
}
sbale->addr = sg_virt(sg);
sbale->length = sg->length;
}
return 0;
}
static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)
{
spin_lock_irq(&qdio->req_q_lock);
if (atomic_read(&qdio->req_q_free) ||
!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return 1;
spin_unlock_irq(&qdio->req_q_lock);
return 0;
}
/**
* zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
* @qdio: pointer to struct zfcp_qdio
*
* The req_q_lock must be held by the caller of this function, and
* this function may only be called from process context; it will
* sleep when waiting for a free sbal.
*
* Returns: 0 on success, -EIO if there is no free sbal after waiting.
*/
int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
{
long ret;
spin_unlock_irq(&qdio->req_q_lock);
ret = wait_event_interruptible_timeout(qdio->req_q_wq,
zfcp_qdio_sbal_check(qdio), 5 * HZ);
if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return -EIO;
if (ret > 0)
return 0;
if (!ret) {
atomic_inc(&qdio->req_q_full);
/* assume hanging outbound queue, try queue recovery */
zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1");
}
spin_lock_irq(&qdio->req_q_lock);
return -EIO;
}
/**
* zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO
* @qdio: pointer to struct zfcp_qdio
* @q_req: pointer to struct zfcp_qdio_req
* Returns: 0 on success, error otherwise
*/
int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
{
int retval;
u8 sbal_number = q_req->sbal_number;
spin_lock(&qdio->stat_lock);
zfcp_qdio_account(qdio);
spin_unlock(&qdio->stat_lock);
retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0,
q_req->sbal_first, sbal_number);
if (unlikely(retval)) {
zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
sbal_number);
return retval;
}
/* account for transferred buffers */
atomic_sub(sbal_number, &qdio->req_q_free);
qdio->req_q_idx += sbal_number;
qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q;
return 0;
}
static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
struct zfcp_qdio *qdio)
{
memset(id, 0, sizeof(*id));
id->cdev = qdio->adapter->ccw_device;
id->q_format = QDIO_ZFCP_QFMT;
memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8);
ASCEBC(id->adapter_name, 8);
id->qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV;
if (enable_multibuffer)
id->qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE;
id->no_input_qs = 1;
id->no_output_qs = 1;
id->input_handler = zfcp_qdio_int_resp;
id->output_handler = zfcp_qdio_int_req;
id->int_parm = (unsigned long) qdio;
id->input_sbal_addr_array = (void **) (qdio->res_q);
id->output_sbal_addr_array = (void **) (qdio->req_q);
id->scan_threshold =
QDIO_MAX_BUFFERS_PER_Q - ZFCP_QDIO_MAX_SBALS_PER_REQ * 2;
}
/**
* zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
* @adapter: pointer to struct zfcp_adapter
* Returns: -ENOMEM on memory allocation error or return value from
* qdio_allocate
*/
static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)
{
struct qdio_initialize init_data;
if (zfcp_qdio_buffers_enqueue(qdio->req_q) ||
zfcp_qdio_buffers_enqueue(qdio->res_q))
return -ENOMEM;
zfcp_qdio_setup_init_data(&init_data, qdio);
init_waitqueue_head(&qdio->req_q_wq);
return qdio_allocate(&init_data);
}
/**
* zfcp_close_qdio - close qdio queues for an adapter
* @qdio: pointer to structure zfcp_qdio
*/
void zfcp_qdio_close(struct zfcp_qdio *qdio)
{
struct zfcp_adapter *adapter = qdio->adapter;
int idx, count;
if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return;
/* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
spin_lock_irq(&qdio->req_q_lock);
atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);
spin_unlock_irq(&qdio->req_q_lock);
wake_up(&qdio->req_q_wq);
qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
/* cleanup used outbound sbals */
count = atomic_read(&qdio->req_q_free);
if (count < QDIO_MAX_BUFFERS_PER_Q) {
idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q;
count = QDIO_MAX_BUFFERS_PER_Q - count;
zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
}
qdio->req_q_idx = 0;
atomic_set(&qdio->req_q_free, 0);
}
/**
* zfcp_qdio_open - prepare and initialize response queue
* @qdio: pointer to struct zfcp_qdio
* Returns: 0 on success, otherwise -EIO
*/
int zfcp_qdio_open(struct zfcp_qdio *qdio)
{
struct qdio_buffer_element *sbale;
struct qdio_initialize init_data;
struct zfcp_adapter *adapter = qdio->adapter;
struct ccw_device *cdev = adapter->ccw_device;
struct qdio_ssqd_desc ssqd;
int cc;
if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
return -EIO;
atomic_clear_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
&qdio->adapter->status);
zfcp_qdio_setup_init_data(&init_data, qdio);
if (qdio_establish(&init_data))
goto failed_establish;
if (qdio_get_ssqd_desc(init_data.cdev, &ssqd))
goto failed_qdio;
if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED)
atomic_set_mask(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED,
&qdio->adapter->status);
if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) {
atomic_set_mask(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER;
} else {
atomic_clear_mask(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER - 1;
}
qdio->max_sbale_per_req =
ZFCP_QDIO_MAX_SBALS_PER_REQ * qdio->max_sbale_per_sbal
- 2;
if (qdio_activate(cdev))
goto failed_qdio;
for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
sbale = &(qdio->res_q[cc]->element[0]);
sbale->length = 0;
sbale->eflags = SBAL_EFLAGS_LAST_ENTRY;
sbale->sflags = 0;
sbale->addr = NULL;
}
if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q))
goto failed_qdio;
/* set index of first available SBALS / number of available SBALS */
qdio->req_q_idx = 0;
atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q);
atomic_set_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
if (adapter->scsi_host) {
adapter->scsi_host->sg_tablesize = qdio->max_sbale_per_req;
adapter->scsi_host->max_sectors = qdio->max_sbale_per_req * 8;
}
return 0;
failed_qdio:
qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
failed_establish:
dev_err(&cdev->dev,
"Setting up the QDIO connection to the FCP adapter failed\n");
return -EIO;
}
void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
{
int p;
if (!qdio)
return;
if (qdio->adapter->ccw_device)
qdio_free(qdio->adapter->ccw_device);
for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) {
free_page((unsigned long) qdio->req_q[p]);
free_page((unsigned long) qdio->res_q[p]);
}
kfree(qdio);
}
int zfcp_qdio_setup(struct zfcp_adapter *adapter)
{
struct zfcp_qdio *qdio;
qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);
if (!qdio)
return -ENOMEM;
qdio->adapter = adapter;
if (zfcp_qdio_allocate(qdio)) {
zfcp_qdio_destroy(qdio);
return -ENOMEM;
}
spin_lock_init(&qdio->req_q_lock);
spin_lock_init(&qdio->stat_lock);
adapter->qdio = qdio;
return 0;
}
/**
* zfcp_qdio_siosl - Trigger logging in FCP channel
* @adapter: The zfcp_adapter where to trigger logging
*
* Call the cio siosl function to trigger hardware logging. This
* wrapper function sets a flag to ensure hardware logging is only
* triggered once before going through qdio shutdown.
*
* The triggers are always run from qdio tasklet context, so no
* additional synchronization is necessary.
*/
void zfcp_qdio_siosl(struct zfcp_adapter *adapter)
{
int rc;
if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED)
return;
rc = ccw_device_siosl(adapter->ccw_device);
if (!rc)
atomic_set_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
&adapter->status);
}