// SPDX-License-Identifier: GPL-2.0
/*
* SCLP "store data in absolute storage"
*
* Copyright IBM Corp. 2003, 2013
* Author(s): Michael Holzheu
*/
#define KMSG_COMPONENT "sclp_sdias"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/completion.h>
#include <linux/sched.h>
#include <asm/sclp.h>
#include <asm/debug.h>
#include <asm/ipl.h>
#include "sclp_sdias.h"
#include "sclp.h"
#include "sclp_rw.h"
#define TRACE(x...) debug_sprintf_event(sdias_dbf, 1, x)
#define SDIAS_RETRIES 300
static struct debug_info *sdias_dbf;
static struct sclp_register sclp_sdias_register = {
.send_mask = EVTYP_SDIAS_MASK,
};
static struct sdias_sccb *sclp_sdias_sccb;
static struct sdias_evbuf sdias_evbuf;
static DECLARE_COMPLETION(evbuf_accepted);
static DECLARE_COMPLETION(evbuf_done);
static DEFINE_MUTEX(sdias_mutex);
/*
* Called by SCLP base when read event data has been completed (async mode only)
*/
static void sclp_sdias_receiver_fn(struct evbuf_header *evbuf)
{
memcpy(&sdias_evbuf, evbuf,
min_t(unsigned long, sizeof(sdias_evbuf), evbuf->length));
complete(&evbuf_done);
TRACE("sclp_sdias_receiver_fn done\n");
}
/*
* Called by SCLP base when sdias event has been accepted
*/
static void sdias_callback(struct sclp_req *request, void *data)
{
complete(&evbuf_accepted);
TRACE("callback done\n");
}
static int sdias_sclp_send(struct sclp_req *req)
{
struct sdias_sccb *sccb = sclp_sdias_sccb;
int retries;
int rc;
for (retries = SDIAS_RETRIES; retries; retries--) {
TRACE("add request\n");
rc = sclp_add_request(req);
if (rc) {
/* not initiated, wait some time and retry */
set_current_state(TASK_INTERRUPTIBLE);
TRACE("add request failed: rc = %i\n",rc);
schedule_timeout(msecs_to_jiffies(500));
continue;
}
/* initiated, wait for completion of service call */
wait_for_completion(&evbuf_accepted);
if (req->status == SCLP_REQ_FAILED) {
TRACE("sclp request failed\n");
continue;
}
/* if not accepted, retry */
if (!(sccb->evbuf.hdr.flags & 0x80)) {
TRACE("sclp request failed: flags=%x\n",
sccb->evbuf.hdr.flags);
continue;
}
/*
* for the sync interface the response is in the initial sccb
*/
if (!sclp_sdias_register.receiver_fn) {
memcpy(&sdias_evbuf, &sccb->evbuf, sizeof(sdias_evbuf));
TRACE("sync request done\n");
return 0;
}
/* otherwise we wait for completion */
wait_for_completion(&evbuf_done);
TRACE("request done\n");
return 0;
}
return -EIO;
}
/*
* Get number of blocks (4K) available in the HSA
*/
int sclp_sdias_blk_count(void)
{
struct sdias_sccb *sccb = sclp_sdias_sccb;
struct sclp_req request;
int rc;
mutex_lock(&sdias_mutex);
memset(sccb, 0, sizeof(*sccb));
memset(&request, 0, sizeof(request));
sccb->hdr.length = sizeof(*sccb);
sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
sccb->evbuf.hdr.type = EVTYP_SDIAS;
sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
sccb->evbuf.event_id = 4712;
sccb->evbuf.dbs = 1;
request.sccb = sccb;
request.command = SCLP_CMDW_WRITE_EVENT_DATA;
request.status = SCLP_REQ_FILLED;
request.callback = sdias_callback;
rc = sdias_sclp_send(&request);
if (rc) {
pr_err("sclp_send failed for get_nr_blocks\n");
goto out;
}
if (sccb->hdr.response_code != 0x0020) {
TRACE("send failed: %x\n", sccb->hdr.response_code);
rc = -EIO;
goto out;
}
switch (sdias_evbuf.event_status) {
case 0:
rc = sdias_evbuf.blk_cnt;
break;
default:
pr_err("SCLP error: %x\n", sdias_evbuf.event_status);
rc = -EIO;
goto out;
}
TRACE("%i blocks\n", rc);
out:
mutex_unlock(&sdias_mutex);
return rc;
}
/*
* Copy from HSA to absolute storage (not reentrant):
*
* @dest : Address of buffer where data should be copied
* @start_blk: Start Block (beginning with 1)
* @nr_blks : Number of 4K blocks to copy
*
* Return Value: 0 : Requested 'number' of blocks of data copied
* <0: ERROR - negative event status
*/
int sclp_sdias_copy(void *dest, int start_blk, int nr_blks)
{
struct sdias_sccb *sccb = sclp_sdias_sccb;
struct sclp_req request;
int rc;
mutex_lock(&sdias_mutex);
memset(sccb, 0, sizeof(*sccb));
memset(&request, 0, sizeof(request));
sccb->hdr.length = sizeof(*sccb);
sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
sccb->evbuf.hdr.type = EVTYP_SDIAS;
sccb->evbuf.hdr.flags = 0;
sccb->evbuf.event_qual = SDIAS_EQ_STORE_DATA;
sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
sccb->evbuf.event_id = 4712;
sccb->evbuf.asa_size = SDIAS_ASA_SIZE_64;
sccb->evbuf.event_status = 0;
sccb->evbuf.blk_cnt = nr_blks;
sccb->evbuf.asa = __pa(dest);
sccb->evbuf.fbn = start_blk;
sccb->evbuf.lbn = 0;
sccb->evbuf.dbs = 1;
request.sccb = sccb;
request.command = SCLP_CMDW_WRITE_EVENT_DATA;
request.status = SCLP_REQ_FILLED;
request.callback = sdias_callback;
rc = sdias_sclp_send(&request);
if (rc) {
pr_err("sclp_send failed: %x\n", rc);
goto out;
}
if (sccb->hdr.response_code != 0x0020) {
TRACE("copy failed: %x\n", sccb->hdr.response_code);
rc = -EIO;
goto out;
}
switch (sdias_evbuf.event_status) {
case SDIAS_EVSTATE_ALL_STORED:
TRACE("all stored\n");
break;
case SDIAS_EVSTATE_PART_STORED:
TRACE("part stored: %i\n", sdias_evbuf.blk_cnt);
break;
case SDIAS_EVSTATE_NO_DATA:
TRACE("no data\n");
fallthrough;
default:
pr_err("Error from SCLP while copying hsa. Event status = %x\n",
sdias_evbuf.event_status);
rc = -EIO;
}
out:
mutex_unlock(&sdias_mutex);
return rc;
}
static int __init sclp_sdias_register_check(void)
{
int rc;
rc = sclp_register(&sclp_sdias_register);
if (rc)
return rc;
if (sclp_sdias_blk_count() == 0) {
sclp_unregister(&sclp_sdias_register);
return -ENODEV;
}
return 0;
}
static int __init sclp_sdias_init_sync(void)
{
TRACE("Try synchronous mode\n");
sclp_sdias_register.receive_mask = 0;
sclp_sdias_register.receiver_fn = NULL;
return sclp_sdias_register_check();
}
static int __init sclp_sdias_init_async(void)
{
TRACE("Try asynchronous mode\n");
sclp_sdias_register.receive_mask = EVTYP_SDIAS_MASK;
sclp_sdias_register.receiver_fn = sclp_sdias_receiver_fn;
return sclp_sdias_register_check();
}
int __init sclp_sdias_init(void)
{
if (!is_ipl_type_dump())
return 0;
sclp_sdias_sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
BUG_ON(!sclp_sdias_sccb);
sdias_dbf = debug_register("dump_sdias", 4, 1, 4 * sizeof(long));
debug_register_view(sdias_dbf, &debug_sprintf_view);
debug_set_level(sdias_dbf, 6);
if (sclp_sdias_init_sync() == 0)
goto out;
if (sclp_sdias_init_async() == 0)
goto out;
TRACE("init failed\n");
free_page((unsigned long) sclp_sdias_sccb);
return -ENODEV;
out:
TRACE("init done\n");
return 0;
}
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