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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/s390/char/sclp_sdias.c
Initial import
Diffstat (limited to 'drivers/s390/char/sclp_sdias.c')
-rw-r--r--drivers/s390/char/sclp_sdias.c277
1 files changed, 277 insertions, 0 deletions
diff --git a/drivers/s390/char/sclp_sdias.c b/drivers/s390/char/sclp_sdias.c
new file mode 100644
index 000000000..eb7cb076c
--- /dev/null
+++ b/drivers/s390/char/sclp_sdias.c
@@ -0,0 +1,277 @@
+/*
+ * 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
+#define SDIAS_SLEEP_TICKS 50
+
+static struct debug_info *sdias_dbf;
+
+static struct sclp_register sclp_sdias_register = {
+ .send_mask = EVTYP_SDIAS_MASK,
+};
+
+static struct sdias_sccb sccb __attribute__((aligned(4096)));
+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)
+{
+ 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(SDIAS_SLEEP_TICKS);
+ 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 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 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 = (unsigned long)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");
+ /* fall through */
+ 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 (ipl_info.type != IPL_TYPE_FCP_DUMP)
+ return 0;
+ 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");
+ return -ENODEV;
+out:
+ TRACE("init done\n");
+ return 0;
+}
+
+void __exit sclp_sdias_exit(void)
+{
+ debug_unregister(sdias_dbf);
+ sclp_unregister(&sclp_sdias_register);
+}