[S390] dasd: Add support for raw ECKD access.
Normal I/O operations through the DASD device driver give only access
to the data fields of an ECKD device even for track based I/O.
This patch extends the DASD device driver to give access to whole
ECKD tracks including count, key and data fields.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 82d9ce3..4e266f4 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -369,6 +369,11 @@
device->state = DASD_STATE_ONLINE;
if (device->block) {
dasd_schedule_block_bh(device->block);
+ if ((device->features & DASD_FEATURE_USERAW)) {
+ disk = device->block->gdp;
+ kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
+ return 0;
+ }
disk = device->block->bdev->bd_disk;
disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
while ((part = disk_part_iter_next(&piter)))
@@ -394,7 +399,7 @@
return rc;
}
device->state = DASD_STATE_READY;
- if (device->block) {
+ if (device->block && !(device->features & DASD_FEATURE_USERAW)) {
disk = device->block->bdev->bd_disk;
disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
while ((part = disk_part_iter_next(&piter)))
@@ -2258,8 +2263,20 @@
{
int max;
- blk_queue_logical_block_size(block->request_queue, block->bp_block);
- max = block->base->discipline->max_blocks << block->s2b_shift;
+ if (block->base->features & DASD_FEATURE_USERAW) {
+ /*
+ * the max_blocks value for raw_track access is 256
+ * it is higher than the native ECKD value because we
+ * only need one ccw per track
+ * so the max_hw_sectors are
+ * 2048 x 512B = 1024kB = 16 tracks
+ */
+ max = 2048;
+ } else {
+ max = block->base->discipline->max_blocks << block->s2b_shift;
+ }
+ blk_queue_logical_block_size(block->request_queue,
+ block->bp_block);
blk_queue_max_hw_sectors(block->request_queue, max);
blk_queue_max_segments(block->request_queue, -1L);
/* with page sized segments we can translate each segement into
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index 47fc886..cb6a67b 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -208,6 +208,8 @@
features |= DASD_FEATURE_READONLY;
else if (len == 4 && !strncmp(str, "diag", 4))
features |= DASD_FEATURE_USEDIAG;
+ else if (len == 3 && !strncmp(str, "raw", 3))
+ features |= DASD_FEATURE_USERAW;
else if (len == 6 && !strncmp(str, "erplog", 6))
features |= DASD_FEATURE_ERPLOG;
else if (len == 8 && !strncmp(str, "failfast", 8))
@@ -857,7 +859,7 @@
spin_lock(&dasd_devmap_lock);
/* Changing diag discipline flag is only allowed in offline state. */
rc = count;
- if (!devmap->device) {
+ if (!devmap->device && !(devmap->features & DASD_FEATURE_USERAW)) {
if (val)
devmap->features |= DASD_FEATURE_USEDIAG;
else
@@ -870,6 +872,56 @@
static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);
+/*
+ * use_raw controls whether the driver should give access to raw eckd data or
+ * operate in standard mode
+ */
+static ssize_t
+dasd_use_raw_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct dasd_devmap *devmap;
+ int use_raw;
+
+ devmap = dasd_find_busid(dev_name(dev));
+ if (!IS_ERR(devmap))
+ use_raw = (devmap->features & DASD_FEATURE_USERAW) != 0;
+ else
+ use_raw = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USERAW) != 0;
+ return sprintf(buf, use_raw ? "1\n" : "0\n");
+}
+
+static ssize_t
+dasd_use_raw_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct dasd_devmap *devmap;
+ ssize_t rc;
+ unsigned long val;
+
+ devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(devmap))
+ return PTR_ERR(devmap);
+
+ if ((strict_strtoul(buf, 10, &val) != 0) || val > 1)
+ return -EINVAL;
+
+ spin_lock(&dasd_devmap_lock);
+ /* Changing diag discipline flag is only allowed in offline state. */
+ rc = count;
+ if (!devmap->device && !(devmap->features & DASD_FEATURE_USEDIAG)) {
+ if (val)
+ devmap->features |= DASD_FEATURE_USERAW;
+ else
+ devmap->features &= ~DASD_FEATURE_USERAW;
+ } else
+ rc = -EPERM;
+ spin_unlock(&dasd_devmap_lock);
+ return rc;
+}
+
+static DEVICE_ATTR(raw_track_access, 0644, dasd_use_raw_show,
+ dasd_use_raw_store);
+
static ssize_t
dasd_discipline_show(struct device *dev, struct device_attribute *attr,
char *buf)
@@ -1232,6 +1284,7 @@
&dev_attr_vendor.attr,
&dev_attr_uid.attr,
&dev_attr_use_diag.attr,
+ &dev_attr_raw_track_access.attr,
&dev_attr_eer_enabled.attr,
&dev_attr_erplog.attr,
&dev_attr_failfast.attr,
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 46eafce..318672d 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -54,6 +54,15 @@
#define ECKD_F7(i) (i->factor7)
#define ECKD_F8(i) (i->factor8)
+/*
+ * raw track access always map to 64k in memory
+ * so it maps to 16 blocks of 4k per track
+ */
+#define DASD_RAW_BLOCK_PER_TRACK 16
+#define DASD_RAW_BLOCKSIZE 4096
+/* 64k are 128 x 512 byte sectors */
+#define DASD_RAW_SECTORS_PER_TRACK 128
+
MODULE_LICENSE("GPL");
static struct dasd_discipline dasd_eckd_discipline;
@@ -385,6 +394,23 @@
data->length = reclen;
data->operation.operation = 0x03;
break;
+ case DASD_ECKD_CCW_WRITE_FULL_TRACK:
+ data->operation.orientation = 0x0;
+ data->operation.operation = 0x3F;
+ data->extended_operation = 0x11;
+ data->length = 0;
+ data->extended_parameter_length = 0x02;
+ if (data->count > 8) {
+ data->extended_parameter[0] = 0xFF;
+ data->extended_parameter[1] = 0xFF;
+ data->extended_parameter[1] <<= (16 - count);
+ } else {
+ data->extended_parameter[0] = 0xFF;
+ data->extended_parameter[0] <<= (8 - count);
+ data->extended_parameter[1] = 0x00;
+ }
+ data->sector = 0xFF;
+ break;
case DASD_ECKD_CCW_WRITE_TRACK_DATA:
data->auxiliary.length_valid = 0x1;
data->length = reclen; /* not tlf, as one might think */
@@ -408,6 +434,12 @@
case DASD_ECKD_CCW_READ_COUNT:
data->operation.operation = 0x06;
break;
+ case DASD_ECKD_CCW_READ_TRACK:
+ data->operation.orientation = 0x1;
+ data->operation.operation = 0x0C;
+ data->extended_parameter_length = 0;
+ data->sector = 0xFF;
+ break;
case DASD_ECKD_CCW_READ_TRACK_DATA:
data->auxiliary.length_valid = 0x1;
data->length = tlf;
@@ -451,10 +483,16 @@
ccw->cmd_code = DASD_ECKD_CCW_PFX;
ccw->flags = 0;
- ccw->count = sizeof(*pfxdata);
- ccw->cda = (__u32) __pa(pfxdata);
+ if (cmd == DASD_ECKD_CCW_WRITE_FULL_TRACK) {
+ ccw->count = sizeof(*pfxdata) + 2;
+ ccw->cda = (__u32) __pa(pfxdata);
+ memset(pfxdata, 0, sizeof(*pfxdata) + 2);
+ } else {
+ ccw->count = sizeof(*pfxdata);
+ ccw->cda = (__u32) __pa(pfxdata);
+ memset(pfxdata, 0, sizeof(*pfxdata));
+ }
- memset(pfxdata, 0, sizeof(*pfxdata));
/* prefix data */
if (format > 1) {
DBF_DEV_EVENT(DBF_ERR, basedev,
@@ -488,6 +526,7 @@
dedata->mask.perm = 0x1;
dedata->attributes.operation = basepriv->attrib.operation;
break;
+ case DASD_ECKD_CCW_READ_TRACK:
case DASD_ECKD_CCW_READ_TRACK_DATA:
dedata->mask.perm = 0x1;
dedata->attributes.operation = basepriv->attrib.operation;
@@ -514,6 +553,11 @@
dedata->attributes.operation = DASD_BYPASS_CACHE;
rc = check_XRC_on_prefix(pfxdata, basedev);
break;
+ case DASD_ECKD_CCW_WRITE_FULL_TRACK:
+ dedata->mask.perm = 0x03;
+ dedata->attributes.operation = basepriv->attrib.operation;
+ dedata->blk_size = 0;
+ break;
case DASD_ECKD_CCW_WRITE_TRACK_DATA:
dedata->mask.perm = 0x02;
dedata->attributes.operation = basepriv->attrib.operation;
@@ -1607,6 +1651,13 @@
dasd_sfree_request(init_cqr, device);
}
+ if (device->features & DASD_FEATURE_USERAW) {
+ block->bp_block = DASD_RAW_BLOCKSIZE;
+ blk_per_trk = DASD_RAW_BLOCK_PER_TRACK;
+ block->s2b_shift = 3;
+ goto raw;
+ }
+
if (status == INIT_CQR_UNFORMATTED) {
dev_warn(&device->cdev->dev, "The DASD is not formatted\n");
return -EMEDIUMTYPE;
@@ -1644,6 +1695,7 @@
dev_warn(&device->cdev->dev,
"Track 0 has no records following the VTOC\n");
}
+
if (count_area != NULL && count_area->kl == 0) {
/* we found notthing violating our disk layout */
if (dasd_check_blocksize(count_area->dl) == 0)
@@ -1659,6 +1711,8 @@
block->s2b_shift++;
blk_per_trk = recs_per_track(&private->rdc_data, 0, block->bp_block);
+
+raw:
block->blocks = (private->real_cyl *
private->rdc_data.trk_per_cyl *
blk_per_trk);
@@ -2741,6 +2795,135 @@
return cqr;
}
+static struct dasd_ccw_req *dasd_raw_build_cp(struct dasd_device *startdev,
+ struct dasd_block *block,
+ struct request *req)
+{
+ struct dasd_eckd_private *private;
+ unsigned long *idaws;
+ struct dasd_device *basedev;
+ struct dasd_ccw_req *cqr;
+ struct ccw1 *ccw;
+ struct req_iterator iter;
+ struct bio_vec *bv;
+ char *dst;
+ unsigned char cmd;
+ unsigned int trkcount;
+ unsigned int seg_len, len_to_track_end;
+ unsigned int first_offs;
+ unsigned int cidaw, cplength, datasize;
+ sector_t first_trk, last_trk;
+ unsigned int pfx_datasize;
+
+ /*
+ * raw track access needs to be mutiple of 64k and on 64k boundary
+ */
+ if ((blk_rq_pos(req) % DASD_RAW_SECTORS_PER_TRACK) != 0) {
+ cqr = ERR_PTR(-EINVAL);
+ goto out;
+ }
+ if (((blk_rq_pos(req) + blk_rq_sectors(req)) %
+ DASD_RAW_SECTORS_PER_TRACK) != 0) {
+ cqr = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+ first_trk = blk_rq_pos(req) / DASD_RAW_SECTORS_PER_TRACK;
+ last_trk = (blk_rq_pos(req) + blk_rq_sectors(req) - 1) /
+ DASD_RAW_SECTORS_PER_TRACK;
+ trkcount = last_trk - first_trk + 1;
+ first_offs = 0;
+ basedev = block->base;
+ private = (struct dasd_eckd_private *) basedev->private;
+
+ if (rq_data_dir(req) == READ)
+ cmd = DASD_ECKD_CCW_READ_TRACK;
+ else if (rq_data_dir(req) == WRITE)
+ cmd = DASD_ECKD_CCW_WRITE_FULL_TRACK;
+ else {
+ cqr = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+ /*
+ * Raw track based I/O needs IDAWs for each page,
+ * and not just for 64 bit addresses.
+ */
+ cidaw = trkcount * DASD_RAW_BLOCK_PER_TRACK;
+
+ /* 1x prefix + one read/write ccw per track */
+ cplength = 1 + trkcount;
+
+ /*
+ * struct PFX_eckd_data has up to 2 byte as extended parameter
+ * this is needed for write full track and has to be mentioned
+ * seperately
+ * add 8 instead of 2 to keep 8 byte boundary
+ */
+ pfx_datasize = sizeof(struct PFX_eckd_data) + 8;
+
+ datasize = pfx_datasize + cidaw * sizeof(unsigned long long);
+
+ /* Allocate the ccw request. */
+ cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, cplength,
+ datasize, startdev);
+ if (IS_ERR(cqr))
+ goto out;
+ ccw = cqr->cpaddr;
+
+ if (prefix_LRE(ccw++, cqr->data, first_trk, last_trk, cmd,
+ basedev, startdev, 1 /* format */, first_offs + 1,
+ trkcount, 0, 0) == -EAGAIN) {
+ /* Clock not in sync and XRC is enabled.
+ * Try again later.
+ */
+ dasd_sfree_request(cqr, startdev);
+ cqr = ERR_PTR(-EAGAIN);
+ goto out;
+ }
+
+ idaws = (unsigned long *)(cqr->data + pfx_datasize);
+
+ len_to_track_end = 0;
+
+ rq_for_each_segment(bv, req, iter) {
+ dst = page_address(bv->bv_page) + bv->bv_offset;
+ seg_len = bv->bv_len;
+ if (!len_to_track_end) {
+ ccw[-1].flags |= CCW_FLAG_CC;
+ ccw->cmd_code = cmd;
+ /* maximum 3390 track size */
+ ccw->count = 57326;
+ /* 64k map to one track */
+ len_to_track_end = 65536;
+ ccw->cda = (__u32)(addr_t)idaws;
+ ccw->flags |= CCW_FLAG_IDA;
+ ccw->flags |= CCW_FLAG_SLI;
+ ccw++;
+ }
+ len_to_track_end -= seg_len;
+ idaws = idal_create_words(idaws, dst, seg_len);
+ }
+
+ if (blk_noretry_request(req) ||
+ block->base->features & DASD_FEATURE_FAILFAST)
+ set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
+ cqr->startdev = startdev;
+ cqr->memdev = startdev;
+ cqr->block = block;
+ cqr->expires = startdev->default_expires * HZ;
+ cqr->lpm = startdev->path_data.ppm;
+ cqr->retries = 256;
+ cqr->buildclk = get_clock();
+ cqr->status = DASD_CQR_FILLED;
+
+ if (IS_ERR(cqr) && PTR_ERR(cqr) != -EAGAIN)
+ cqr = NULL;
+out:
+ return cqr;
+}
+
+
static int
dasd_eckd_free_cp(struct dasd_ccw_req *cqr, struct request *req)
{
@@ -2845,7 +3028,10 @@
spin_lock_irqsave(get_ccwdev_lock(startdev->cdev), flags);
private->count++;
- cqr = dasd_eckd_build_cp(startdev, block, req);
+ if ((base->features & DASD_FEATURE_USERAW))
+ cqr = dasd_raw_build_cp(startdev, block, req);
+ else
+ cqr = dasd_eckd_build_cp(startdev, block, req);
if (IS_ERR(cqr))
private->count--;
spin_unlock_irqrestore(get_ccwdev_lock(startdev->cdev), flags);
diff --git a/drivers/s390/block/dasd_eckd.h b/drivers/s390/block/dasd_eckd.h
index 5051f37..4a688a8 100644
--- a/drivers/s390/block/dasd_eckd.h
+++ b/drivers/s390/block/dasd_eckd.h
@@ -37,11 +37,13 @@
#define DASD_ECKD_CCW_WRITE_KD_MT 0x8d
#define DASD_ECKD_CCW_READ_KD_MT 0x8e
#define DASD_ECKD_CCW_RELEASE 0x94
+#define DASD_ECKD_CCW_WRITE_FULL_TRACK 0x95
#define DASD_ECKD_CCW_READ_CKD_MT 0x9e
#define DASD_ECKD_CCW_WRITE_CKD_MT 0x9d
#define DASD_ECKD_CCW_WRITE_TRACK_DATA 0xA5
#define DASD_ECKD_CCW_READ_TRACK_DATA 0xA6
#define DASD_ECKD_CCW_RESERVE 0xB4
+#define DASD_ECKD_CCW_READ_TRACK 0xDE
#define DASD_ECKD_CCW_PFX 0xE7
#define DASD_ECKD_CCW_PFX_READ 0xEA
#define DASD_ECKD_CCW_RSCK 0xF9