1 files changed, 541 insertions, 0 deletions

diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c
new file mode 100644
index 000000000000..127699830fa1
--- /dev/null
+++ b/drivers/s390/block/dasd_diag.c
@@ -0,0 +1,541 @@
+/* 
+ * File...........: linux/drivers/s390/block/dasd_diag.c
+ * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
+ * Based on.......: linux/drivers/s390/block/mdisk.c
+ * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
+ * Bugreports.to..: <Linux390@de.ibm.com>
+ * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
+ *
+ * $Revision: 1.42 $
+ */
+
+#include <linux/config.h>
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/hdreg.h>        /* HDIO_GETGEO                      */
+#include <linux/bio.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <asm/dasd.h>
+#include <asm/debug.h>
+#include <asm/ebcdic.h>
+#include <asm/io.h>
+#include <asm/s390_ext.h>
+#include <asm/todclk.h>
+
+#include "dasd_int.h"
+#include "dasd_diag.h"
+
+#ifdef PRINTK_HEADER
+#undef PRINTK_HEADER
+#endif                          /* PRINTK_HEADER */
+#define PRINTK_HEADER "dasd(diag):"
+
+MODULE_LICENSE("GPL");
+
+struct dasd_discipline dasd_diag_discipline;
+
+struct dasd_diag_private {
+        struct dasd_diag_characteristics rdc_data;
+        struct dasd_diag_rw_io iob;
+        struct dasd_diag_init_io iib;
+        unsigned int pt_block;
+};
+
+struct dasd_diag_req {
+        int block_count;
+        struct dasd_diag_bio bio[0];
+};
+
+static __inline__ int
+dia250(void *iob, int cmd)
+{
+        int rc;
+
+        __asm__ __volatile__("    lhi   %0,3\n"
+                             "    lr    0,%2\n"
+                             "    diag  0,%1,0x250\n"
+                             "0:  ipm   %0\n"
+                             "    srl   %0,28\n"
+                             "    or    %0,1\n"
+                             "1:\n"
+#ifndef CONFIG_ARCH_S390X
+                             ".section __ex_table,\"a\"\n"
+                             "    .align 4\n"
+                             "    .long 0b,1b\n"
+                             ".previous\n"
+#else
+                             ".section __ex_table,\"a\"\n"
+                             "    .align 8\n"
+                             "    .quad  0b,1b\n"
+                             ".previous\n"
+#endif
+                             : "=&d" (rc)
+                             : "d" (cmd), "d" ((void *) __pa(iob))
+                             : "0", "1", "cc");
+        return rc;
+}
+
+static __inline__ int
+mdsk_init_io(struct dasd_device * device, int blocksize, int offset, int size)
+{
+        struct dasd_diag_private *private;
+        struct dasd_diag_init_io *iib;
+        int rc;
+
+        private = (struct dasd_diag_private *) device->private;
+        iib = &private->iib;
+        memset(iib, 0, sizeof (struct dasd_diag_init_io));
+
+        iib->dev_nr = _ccw_device_get_device_number(device->cdev);
+        iib->block_size = blocksize;
+        iib->offset = offset;
+        iib->start_block = 0;
+        iib->end_block = size;
+
+        rc = dia250(iib, INIT_BIO);
+
+        return rc & 3;
+}
+
+static __inline__ int
+mdsk_term_io(struct dasd_device * device)
+{
+        struct dasd_diag_private *private;
+        struct dasd_diag_init_io *iib;
+        int rc;
+
+        private = (struct dasd_diag_private *) device->private;
+        iib = &private->iib;
+        memset(iib, 0, sizeof (struct dasd_diag_init_io));
+        iib->dev_nr = _ccw_device_get_device_number(device->cdev);
+        rc = dia250(iib, TERM_BIO);
+        return rc & 3;
+}
+
+static int
+dasd_start_diag(struct dasd_ccw_req * cqr)
+{
+        struct dasd_device *device;
+        struct dasd_diag_private *private;
+        struct dasd_diag_req *dreq;
+        int rc;
+
+        device = cqr->device;
+        private = (struct dasd_diag_private *) device->private;
+        dreq = (struct dasd_diag_req *) cqr->data;
+
+        private->iob.dev_nr = _ccw_device_get_device_number(device->cdev);
+        private->iob.key = 0;
+        private->iob.flags = 2; /* do asynchronous io */
+        private->iob.block_count = dreq->block_count;
+        private->iob.interrupt_params = (u32)(addr_t) cqr;
+        private->iob.bio_list = __pa(dreq->bio);
+
+        cqr->startclk = get_clock();
+
+        rc = dia250(&private->iob, RW_BIO);
+        if (rc > 8) {
+                DEV_MESSAGE(KERN_WARNING, device, "dia250 returned CC %d", rc);
+                cqr->status = DASD_CQR_ERROR;
+        } else if (rc == 0) {
+                cqr->status = DASD_CQR_DONE;
+                dasd_schedule_bh(device);
+        } else {
+                cqr->status = DASD_CQR_IN_IO;
+                rc = 0;
+        }
+        return rc;
+}
+
+static void
+dasd_ext_handler(struct pt_regs *regs, __u16 code)
+{
+        struct dasd_ccw_req *cqr, *next;
+        struct dasd_device *device;
+        unsigned long long expires;
+        unsigned long flags;
+        char status;
+        int ip;
+
+        /*
+         * Get the external interruption subcode. VM stores
+         * this in the 'cpu address' field associated with
+         * the external interrupt. For diag 250 the subcode
+         * needs to be 3.
+         */
+        if ((S390_lowcore.cpu_addr & 0xff00) != 0x0300)
+                return;
+        status = *((char *) &S390_lowcore.ext_params + 5);
+        ip = S390_lowcore.ext_params;
+
+        if (!ip) {              /* no intparm: unsolicited interrupt */
+                MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
+                return;
+        }
+        cqr = (struct dasd_ccw_req *)(addr_t) ip;
+        device = (struct dasd_device *) cqr->device;
+        if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
+                DEV_MESSAGE(KERN_WARNING, device,
+                            " magic number of dasd_ccw_req 0x%08X doesn't"
+                            " match discipline 0x%08X",
+                            cqr->magic, *(int *) (&device->discipline->name));
+                return;
+        }
+
+        /* get irq lock to modify request queue */
+        spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
+
+        cqr->stopclk = get_clock();
+
+        expires = 0;
+        if (status == 0) {
+                cqr->status = DASD_CQR_DONE;
+                /* Start first request on queue if possible -> fast_io. */
+                if (!list_empty(&device->ccw_queue)) {
+                        next = list_entry(device->ccw_queue.next,
+                                          struct dasd_ccw_req, list);
+                        if (next->status == DASD_CQR_QUEUED) {
+                                if (dasd_start_diag(next) == 0)
+                                        expires = next->expires;
+                                else
+                                        DEV_MESSAGE(KERN_WARNING, device, "%s",
+                                                    "Interrupt fastpath "
+                                                    "failed!");
+                        }
+                }
+        } else 
+                cqr->status = DASD_CQR_FAILED;
+
+        if (expires != 0)
+                dasd_set_timer(device, expires);
+        else
+                dasd_clear_timer(device);
+        dasd_schedule_bh(device);
+
+        spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
+}
+
+static int
+dasd_diag_check_device(struct dasd_device *device)
+{
+        struct dasd_diag_private *private;
+        struct dasd_diag_characteristics *rdc_data;
+        struct dasd_diag_bio bio;
+        long *label;
+        int sb, bsize;
+        int rc;
+
+        private = (struct dasd_diag_private *) device->private;
+        if (private == NULL) {
+                private = kmalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
+                if (private == NULL) {
+                        DEV_MESSAGE(KERN_WARNING, device, "%s",
+                                "memory allocation failed for private data");
+                        return -ENOMEM;
+                }
+                device->private = (void *) private;
+        }
+        /* Read Device Characteristics */
+        rdc_data = (void *) &(private->rdc_data);
+        rdc_data->dev_nr = _ccw_device_get_device_number(device->cdev);
+        rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
+
+        rc = diag210((struct diag210 *) rdc_data);
+        if (rc)
+                return -ENOTSUPP;
+
+        /* Figure out position of label block */
+        switch (private->rdc_data.vdev_class) {
+        case DEV_CLASS_FBA:
+                private->pt_block = 1;
+                break;
+        case DEV_CLASS_ECKD:
+                private->pt_block = 2;
+                break;
+        default:
+                return -ENOTSUPP;
+        }
+
+        DBF_DEV_EVENT(DBF_INFO, device,
+                      "%04X: %04X on real %04X/%02X",
+                      rdc_data->dev_nr,
+                      rdc_data->vdev_type,
+                      rdc_data->rdev_type, rdc_data->rdev_model);
+
+        /* terminate all outstanding operations */
+        mdsk_term_io(device);
+
+        /* figure out blocksize of device */
+        label = (long *) get_zeroed_page(GFP_KERNEL);
+        if (label == NULL)  {
+                DEV_MESSAGE(KERN_WARNING, device, "%s",
+                            "No memory to allocate initialization request");
+                return -ENOMEM;
+        }
+        /* try all sizes - needed for ECKD devices */
+        for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
+                mdsk_init_io(device, bsize, 0, 64);
+                memset(&bio, 0, sizeof (struct dasd_diag_bio));
+                bio.type = MDSK_READ_REQ;
+                bio.block_number = private->pt_block + 1;
+                bio.buffer = __pa(label);
+                memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
+                private->iob.dev_nr = rdc_data->dev_nr;
+                private->iob.key = 0;
+                private->iob.flags = 0; /* do synchronous io */
+                private->iob.block_count = 1;
+                private->iob.interrupt_params = 0;
+                private->iob.bio_list = __pa(&bio);
+                if (dia250(&private->iob, RW_BIO) == 0)
+                        break;
+                mdsk_term_io(device);
+        }
+        if (bsize <= PAGE_SIZE && label[0] == 0xc3d4e2f1) {
+                /* get formatted blocksize from label block */
+                bsize = (int) label[3];
+                device->blocks = label[7];
+                device->bp_block = bsize;
+                device->s2b_shift = 0;  /* bits to shift 512 to get a block */
+                for (sb = 512; sb < bsize; sb = sb << 1)
+                        device->s2b_shift++;
+                
+                DEV_MESSAGE(KERN_INFO, device,
+                            "capacity (%dkB blks): %ldkB",
+                            (device->bp_block >> 10),
+                            (device->blocks << device->s2b_shift) >> 1);
+                rc = 0;
+        } else {
+                if (bsize > PAGE_SIZE)
+                        DEV_MESSAGE(KERN_WARNING, device, "%s",
+                                    "DIAG access failed");
+                else
+                        DEV_MESSAGE(KERN_WARNING, device, "%s",
+                                    "volume is not CMS formatted");
+                rc = -EMEDIUMTYPE;
+        }
+        free_page((long) label);
+        return rc;
+}
+
+static int
+dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
+{
+        if (dasd_check_blocksize(device->bp_block) != 0)
+                return -EINVAL;
+        geo->cylinders = (device->blocks << device->s2b_shift) >> 10;
+        geo->heads = 16;
+        geo->sectors = 128 >> device->s2b_shift;
+        return 0;
+}
+
+static dasd_era_t
+dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat)
+{
+        return dasd_era_fatal;
+}
+
+static dasd_erp_fn_t
+dasd_diag_erp_action(struct dasd_ccw_req * cqr)
+{
+        return dasd_default_erp_action;
+}
+
+static dasd_erp_fn_t
+dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
+{
+        return dasd_default_erp_postaction;
+}
+
+static struct dasd_ccw_req *
+dasd_diag_build_cp(struct dasd_device * device, struct request *req)
+{
+        struct dasd_ccw_req *cqr;
+        struct dasd_diag_req *dreq;
+        struct dasd_diag_bio *dbio;
+        struct bio *bio;
+        struct bio_vec *bv;
+        char *dst;
+        int count, datasize;
+        sector_t recid, first_rec, last_rec;
+        unsigned blksize, off;
+        unsigned char rw_cmd;
+        int i;
+
+        if (rq_data_dir(req) == READ)
+                rw_cmd = MDSK_READ_REQ;
+        else if (rq_data_dir(req) == WRITE)
+                rw_cmd = MDSK_WRITE_REQ;
+        else
+                return ERR_PTR(-EINVAL);
+        blksize = device->bp_block;
+        /* Calculate record id of first and last block. */
+        first_rec = req->sector >> device->s2b_shift;
+        last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift;
+        /* Check struct bio and count the number of blocks for the request. */
+        count = 0;
+        rq_for_each_bio(bio, req) {
+                bio_for_each_segment(bv, bio, i) {
+                        if (bv->bv_len & (blksize - 1))
+                                /* Fba can only do full blocks. */
+                                return ERR_PTR(-EINVAL);
+                        count += bv->bv_len >> (device->s2b_shift + 9);
+                }
+        }
+        /* Paranoia. */
+        if (count != last_rec - first_rec + 1)
+                return ERR_PTR(-EINVAL);
+        /* Build the request */
+        datasize = sizeof(struct dasd_diag_req) +
+                count*sizeof(struct dasd_diag_bio);
+        cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
+                                   datasize, device);
+        if (IS_ERR(cqr))
+                return cqr;
+        
+        dreq = (struct dasd_diag_req *) cqr->data;
+        dreq->block_count = count;
+        dbio = dreq->bio;
+        recid = first_rec;
+        rq_for_each_bio(bio, req) {
+                bio_for_each_segment(bv, bio, i) {
+                        dst = page_address(bv->bv_page) + bv->bv_offset;
+                        for (off = 0; off < bv->bv_len; off += blksize) {
+                                memset(dbio, 0, sizeof (struct dasd_diag_bio));
+                                dbio->type = rw_cmd;
+                                dbio->block_number = recid + 1;
+                                dbio->buffer = __pa(dst);
+                                dbio++;
+                                dst += blksize;
+                                recid++;
+                        }
+                }
+        }
+        cqr->buildclk = get_clock();
+        cqr->device = device;
+        cqr->expires = 50 * HZ; /* 50 seconds */
+        cqr->status = DASD_CQR_FILLED;
+        return cqr;
+}
+
+static int
+dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
+{
+        int status;
+
+        status = cqr->status == DASD_CQR_DONE;
+        dasd_sfree_request(cqr, cqr->device);
+        return status;
+}
+
+static int
+dasd_diag_fill_info(struct dasd_device * device,
+                    struct dasd_information2_t * info)
+{
+        struct dasd_diag_private *private;
+
+        private = (struct dasd_diag_private *) device->private;
+        info->label_block = private->pt_block;
+        info->FBA_layout = 1;
+        info->format = DASD_FORMAT_LDL;
+        info->characteristics_size = sizeof (struct dasd_diag_characteristics);
+        memcpy(info->characteristics,
+               &((struct dasd_diag_private *) device->private)->rdc_data,
+               sizeof (struct dasd_diag_characteristics));
+        info->confdata_size = 0;
+        return 0;
+}
+
+static void
+dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
+                     struct irb *stat)
+{
+        DEV_MESSAGE(KERN_ERR, device, "%s",
+                    "dump sense not available for DIAG data");
+}
+
+/*
+ * max_blocks is dependent on the amount of storage that is available
+ * in the static io buffer for each device. Currently each device has
+ * 8192 bytes (=2 pages). dasd diag is only relevant for 31 bit.
+ * The struct dasd_ccw_req has 96 bytes, the struct dasd_diag_req has
+ * 8 bytes and the struct dasd_diag_bio for each block has 16 bytes. 
+ * That makes:
+ * (8192 - 96 - 8) / 16 = 505.5 blocks at maximum.
+ * We want to fit two into the available memory so that we can immediately
+ * start the next request if one finishes off. That makes 252.75 blocks
+ * for one request. Give a little safety and the result is 240.
+ */
+struct dasd_discipline dasd_diag_discipline = {
+        .owner = THIS_MODULE,
+        .name = "DIAG",
+        .ebcname = "DIAG",
+        .max_blocks = 240,
+        .check_device = dasd_diag_check_device,
+        .fill_geometry = dasd_diag_fill_geometry,
+        .start_IO = dasd_start_diag,
+        .examine_error = dasd_diag_examine_error,
+        .erp_action = dasd_diag_erp_action,
+        .erp_postaction = dasd_diag_erp_postaction,
+        .build_cp = dasd_diag_build_cp,
+        .free_cp = dasd_diag_free_cp,
+        .dump_sense = dasd_diag_dump_sense,
+        .fill_info = dasd_diag_fill_info,
+};
+
+static int __init
+dasd_diag_init(void)
+{
+        if (!MACHINE_IS_VM) {
+                MESSAGE_LOG(KERN_INFO,
+                            "Machine is not VM: %s "
+                            "discipline not initializing",
+                            dasd_diag_discipline.name);
+                return -EINVAL;
+        }
+        ASCEBC(dasd_diag_discipline.ebcname, 4);
+
+        ctl_set_bit(0, 9);
+        register_external_interrupt(0x2603, dasd_ext_handler);
+        dasd_diag_discipline_pointer = &dasd_diag_discipline;
+        return 0;
+}
+
+static void __exit
+dasd_diag_cleanup(void)
+{
+        if (!MACHINE_IS_VM) {
+                MESSAGE_LOG(KERN_INFO,
+                            "Machine is not VM: %s "
+                            "discipline not cleaned",
+                            dasd_diag_discipline.name);
+                return;
+        }
+        unregister_external_interrupt(0x2603, dasd_ext_handler);
+        ctl_clear_bit(0, 9);
+        dasd_diag_discipline_pointer = NULL;
+}
+
+module_init(dasd_diag_init);
+module_exit(dasd_diag_cleanup);
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-indent-level: 4 
+ * c-brace-imaginary-offset: 0
+ * c-brace-offset: -4
+ * c-argdecl-indent: 4
+ * c-label-offset: -4
+ * c-continued-statement-offset: 4
+ * c-continued-brace-offset: 0
+ * indent-tabs-mode: 1
+ * tab-width: 8
+ * End:
+ */