diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/s390/block/dasd_diag.c |
Initial import
Diffstat (limited to 'drivers/s390/block/dasd_diag.c')
-rw-r--r-- | drivers/s390/block/dasd_diag.c | 663 |
1 files changed, 663 insertions, 0 deletions
diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c new file mode 100644 index 000000000..c062f1620 --- /dev/null +++ b/drivers/s390/block/dasd_diag.c @@ -0,0 +1,663 @@ +/* + * 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> + * Copyright IBM Corp. 1999, 2000 + * + */ + +#define KMSG_COMPONENT "dasd" + +#include <linux/kernel_stat.h> +#include <linux/stddef.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/hdreg.h> +#include <linux/bio.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/jiffies.h> + +#include <asm/dasd.h> +#include <asm/debug.h> +#include <asm/ebcdic.h> +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/vtoc.h> +#include <asm/diag.h> + +#include "dasd_int.h" +#include "dasd_diag.h" + +#define PRINTK_HEADER "dasd(diag):" + +MODULE_LICENSE("GPL"); + +/* The maximum number of blocks per request (max_blocks) is dependent on the + * amount of storage that is available in the static I/O buffer for each + * device. Currently each device gets 2 pages. We want to fit two requests + * into the available memory so that we can immediately start the next if one + * finishes. */ +#define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \ + sizeof(struct dasd_diag_req)) / \ + sizeof(struct dasd_diag_bio)) / 2) +#define DIAG_MAX_RETRIES 32 +#define DIAG_TIMEOUT 50 + +static 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; + blocknum_t pt_block; + struct ccw_dev_id dev_id; +}; + +struct dasd_diag_req { + unsigned int block_count; + struct dasd_diag_bio bio[0]; +}; + +static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */ + +/* Perform DIAG250 call with block I/O parameter list iob (input and output) + * and function code cmd. + * In case of an exception return 3. Otherwise return result of bitwise OR of + * resulting condition code and DIAG return code. */ +static inline int dia250(void *iob, int cmd) +{ + register unsigned long reg2 asm ("2") = (unsigned long) iob; + typedef union { + struct dasd_diag_init_io init_io; + struct dasd_diag_rw_io rw_io; + } addr_type; + int rc; + + rc = 3; + asm volatile( + " diag 2,%2,0x250\n" + "0: ipm %0\n" + " srl %0,28\n" + " or %0,3\n" + "1:\n" + EX_TABLE(0b,1b) + : "+d" (rc), "=m" (*(addr_type *) iob) + : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob) + : "3", "cc"); + return rc; +} + +/* Initialize block I/O to DIAG device using the specified blocksize and + * block offset. On success, return zero and set end_block to contain the + * number of blocks on the device minus the specified offset. Return non-zero + * otherwise. */ +static inline int +mdsk_init_io(struct dasd_device *device, unsigned int blocksize, + blocknum_t offset, blocknum_t *end_block) +{ + 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 = private->dev_id.devno; + iib->block_size = blocksize; + iib->offset = offset; + iib->flaga = DASD_DIAG_FLAGA_DEFAULT; + + rc = dia250(iib, INIT_BIO); + + if ((rc & 3) == 0 && end_block) + *end_block = iib->end_block; + + return rc; +} + +/* Remove block I/O environment for device. Return zero on success, non-zero + * otherwise. */ +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 = private->dev_id.devno; + rc = dia250(iib, TERM_BIO); + return rc; +} + +/* Error recovery for failed DIAG requests - try to reestablish the DIAG + * environment. */ +static void +dasd_diag_erp(struct dasd_device *device) +{ + int rc; + + mdsk_term_io(device); + rc = mdsk_init_io(device, device->block->bp_block, 0, NULL); + if (rc == 4) { + if (!(test_and_set_bit(DASD_FLAG_DEVICE_RO, &device->flags))) + pr_warning("%s: The access mode of a DIAG device " + "changed to read-only\n", + dev_name(&device->cdev->dev)); + rc = 0; + } + if (rc) + pr_warning("%s: DIAG ERP failed with " + "rc=%d\n", dev_name(&device->cdev->dev), rc); +} + +/* Start a given request at the device. Return zero on success, non-zero + * otherwise. */ +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->startdev; + if (cqr->retries < 0) { + DBF_DEV_EVENT(DBF_ERR, device, "DIAG start_IO: request %p " + "- no retry left)", cqr); + cqr->status = DASD_CQR_ERROR; + return -EIO; + } + private = (struct dasd_diag_private *) device->private; + dreq = (struct dasd_diag_req *) cqr->data; + + private->iob.dev_nr = private->dev_id.devno; + private->iob.key = 0; + private->iob.flags = DASD_DIAG_RWFLAG_ASYNC; + private->iob.block_count = dreq->block_count; + private->iob.interrupt_params = (addr_t) cqr; + private->iob.bio_list = dreq->bio; + private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; + + cqr->startclk = get_tod_clock(); + cqr->starttime = jiffies; + cqr->retries--; + + rc = dia250(&private->iob, RW_BIO); + switch (rc) { + case 0: /* Synchronous I/O finished successfully */ + cqr->stopclk = get_tod_clock(); + cqr->status = DASD_CQR_SUCCESS; + /* Indicate to calling function that only a dasd_schedule_bh() + and no timer is needed */ + rc = -EACCES; + break; + case 8: /* Asynchronous I/O was started */ + cqr->status = DASD_CQR_IN_IO; + rc = 0; + break; + default: /* Error condition */ + cqr->status = DASD_CQR_QUEUED; + DBF_DEV_EVENT(DBF_WARNING, device, "dia250 returned rc=%d", rc); + dasd_diag_erp(device); + rc = -EIO; + break; + } + cqr->intrc = rc; + return rc; +} + +/* Terminate given request at the device. */ +static int +dasd_diag_term_IO(struct dasd_ccw_req * cqr) +{ + struct dasd_device *device; + + device = cqr->startdev; + mdsk_term_io(device); + mdsk_init_io(device, device->block->bp_block, 0, NULL); + cqr->status = DASD_CQR_CLEAR_PENDING; + cqr->stopclk = get_tod_clock(); + dasd_schedule_device_bh(device); + return 0; +} + +/* Handle external interruption. */ +static void dasd_ext_handler(struct ext_code ext_code, + unsigned int param32, unsigned long param64) +{ + struct dasd_ccw_req *cqr, *next; + struct dasd_device *device; + unsigned long long expires; + unsigned long flags; + addr_t ip; + int rc; + + switch (ext_code.subcode >> 8) { + case DASD_DIAG_CODE_31BIT: + ip = (addr_t) param32; + break; + case DASD_DIAG_CODE_64BIT: + ip = (addr_t) param64; + break; + default: + return; + } + inc_irq_stat(IRQEXT_DSD); + if (!ip) { /* no intparm: unsolicited interrupt */ + DBF_EVENT(DBF_NOTICE, "%s", "caught unsolicited " + "interrupt"); + return; + } + cqr = (struct dasd_ccw_req *) ip; + device = (struct dasd_device *) cqr->startdev; + if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { + DBF_DEV_EVENT(DBF_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); + + /* Check for a pending clear operation */ + if (cqr->status == DASD_CQR_CLEAR_PENDING) { + cqr->status = DASD_CQR_CLEARED; + dasd_device_clear_timer(device); + dasd_schedule_device_bh(device); + spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); + return; + } + + cqr->stopclk = get_tod_clock(); + + expires = 0; + if ((ext_code.subcode & 0xff) == 0) { + cqr->status = DASD_CQR_SUCCESS; + /* 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, devlist); + if (next->status == DASD_CQR_QUEUED) { + rc = dasd_start_diag(next); + if (rc == 0) + expires = next->expires; + } + } + } else { + cqr->status = DASD_CQR_QUEUED; + DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for " + "request %p was %d (%d retries left)", cqr, + ext_code.subcode & 0xff, cqr->retries); + dasd_diag_erp(device); + } + + if (expires != 0) + dasd_device_set_timer(device, expires); + else + dasd_device_clear_timer(device); + dasd_schedule_device_bh(device); + + spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); +} + +/* Check whether device can be controlled by DIAG discipline. Return zero on + * success, non-zero otherwise. */ +static int +dasd_diag_check_device(struct dasd_device *device) +{ + struct dasd_block *block; + struct dasd_diag_private *private; + struct dasd_diag_characteristics *rdc_data; + struct dasd_diag_bio bio; + struct vtoc_cms_label *label; + blocknum_t end_block; + unsigned int sb, bsize; + int rc; + + private = (struct dasd_diag_private *) device->private; + if (private == NULL) { + private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL); + if (private == NULL) { + DBF_DEV_EVENT(DBF_WARNING, device, "%s", + "Allocating memory for private DASD data " + "failed\n"); + return -ENOMEM; + } + ccw_device_get_id(device->cdev, &private->dev_id); + device->private = (void *) private; + } + block = dasd_alloc_block(); + if (IS_ERR(block)) { + DBF_DEV_EVENT(DBF_WARNING, device, "%s", + "could not allocate dasd block structure"); + device->private = NULL; + kfree(private); + return PTR_ERR(block); + } + device->block = block; + block->base = device; + + /* Read Device Characteristics */ + rdc_data = (void *) &(private->rdc_data); + rdc_data->dev_nr = private->dev_id.devno; + rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics); + + rc = diag210((struct diag210 *) rdc_data); + if (rc) { + DBF_DEV_EVENT(DBF_WARNING, device, "failed to retrieve device " + "information (rc=%d)", rc); + rc = -EOPNOTSUPP; + goto out; + } + + device->default_expires = DIAG_TIMEOUT; + device->default_retries = DIAG_MAX_RETRIES; + + /* 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: + pr_warning("%s: Device type %d is not supported " + "in DIAG mode\n", dev_name(&device->cdev->dev), + private->rdc_data.vdev_class); + rc = -EOPNOTSUPP; + goto out; + } + + 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 = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL); + if (label == NULL) { + DBF_DEV_EVENT(DBF_WARNING, device, "%s", + "No memory to allocate initialization request"); + rc = -ENOMEM; + goto out; + } + rc = 0; + end_block = 0; + /* try all sizes - needed for ECKD devices */ + for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) { + mdsk_init_io(device, bsize, 0, &end_block); + memset(&bio, 0, sizeof (struct dasd_diag_bio)); + bio.type = MDSK_READ_REQ; + bio.block_number = private->pt_block + 1; + bio.buffer = 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 = &bio; + private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; + rc = dia250(&private->iob, RW_BIO); + if (rc == 3) { + pr_warning("%s: A 64-bit DIAG call failed\n", + dev_name(&device->cdev->dev)); + rc = -EOPNOTSUPP; + goto out_label; + } + mdsk_term_io(device); + if (rc == 0) + break; + } + if (bsize > PAGE_SIZE) { + pr_warning("%s: Accessing the DASD failed because of an " + "incorrect format (rc=%d)\n", + dev_name(&device->cdev->dev), rc); + rc = -EIO; + goto out_label; + } + /* check for label block */ + if (memcmp(label->label_id, DASD_DIAG_CMS1, + sizeof(DASD_DIAG_CMS1)) == 0) { + /* get formatted blocksize from label block */ + bsize = (unsigned int) label->block_size; + block->blocks = (unsigned long) label->block_count; + } else + block->blocks = end_block; + block->bp_block = bsize; + block->s2b_shift = 0; /* bits to shift 512 to get a block */ + for (sb = 512; sb < bsize; sb = sb << 1) + block->s2b_shift++; + rc = mdsk_init_io(device, block->bp_block, 0, NULL); + if (rc && (rc != 4)) { + pr_warning("%s: DIAG initialization failed with rc=%d\n", + dev_name(&device->cdev->dev), rc); + rc = -EIO; + } else { + if (rc == 4) + set_bit(DASD_FLAG_DEVICE_RO, &device->flags); + pr_info("%s: New DASD with %ld byte/block, total size %ld " + "KB%s\n", dev_name(&device->cdev->dev), + (unsigned long) block->bp_block, + (unsigned long) (block->blocks << + block->s2b_shift) >> 1, + (rc == 4) ? ", read-only device" : ""); + rc = 0; + } +out_label: + free_page((long) label); +out: + if (rc) { + device->block = NULL; + dasd_free_block(block); + device->private = NULL; + kfree(private); + } + return rc; +} + +/* Fill in virtual disk geometry for device. Return zero on success, non-zero + * otherwise. */ +static int +dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo) +{ + if (dasd_check_blocksize(block->bp_block) != 0) + return -EINVAL; + geo->cylinders = (block->blocks << block->s2b_shift) >> 10; + geo->heads = 16; + geo->sectors = 128 >> block->s2b_shift; + return 0; +} + +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; +} + +/* Create DASD request from block device request. Return pointer to new + * request on success, ERR_PTR otherwise. */ +static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev, + struct dasd_block *block, + struct request *req) +{ + struct dasd_ccw_req *cqr; + struct dasd_diag_req *dreq; + struct dasd_diag_bio *dbio; + struct req_iterator iter; + struct bio_vec bv; + char *dst; + unsigned int count, datasize; + sector_t recid, first_rec, last_rec; + unsigned int blksize, off; + unsigned char rw_cmd; + + 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 = block->bp_block; + /* Calculate record id of first and last block. */ + first_rec = blk_rq_pos(req) >> block->s2b_shift; + last_rec = + (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift; + /* Check struct bio and count the number of blocks for the request. */ + count = 0; + rq_for_each_segment(bv, req, iter) { + if (bv.bv_len & (blksize - 1)) + /* Fba can only do full blocks. */ + return ERR_PTR(-EINVAL); + count += bv.bv_len >> (block->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_MAGIC, 0, datasize, memdev); + 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_segment(bv, req, iter) { + 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 = dst; + dbio++; + dst += blksize; + recid++; + } + } + cqr->retries = memdev->default_retries; + cqr->buildclk = get_tod_clock(); + if (blk_noretry_request(req) || + block->base->features & DASD_FEATURE_FAILFAST) + set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); + cqr->startdev = memdev; + cqr->memdev = memdev; + cqr->block = block; + cqr->expires = memdev->default_expires * HZ; + cqr->status = DASD_CQR_FILLED; + return cqr; +} + +/* Release DASD request. Return non-zero if request was successful, zero + * otherwise. */ +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->memdev); + return status; +} + +static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr) +{ + if (cqr->retries < 0) + cqr->status = DASD_CQR_FAILED; + else + cqr->status = DASD_CQR_FILLED; +}; + +/* Fill in IOCTL data for device. */ +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 = (unsigned int) 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) +{ + DBF_DEV_EVENT(DBF_WARNING, device, "%s", + "dump sense not available for DIAG data"); +} + +static struct dasd_discipline dasd_diag_discipline = { + .owner = THIS_MODULE, + .name = "DIAG", + .ebcname = "DIAG", + .max_blocks = DIAG_MAX_BLOCKS, + .check_device = dasd_diag_check_device, + .verify_path = dasd_generic_verify_path, + .fill_geometry = dasd_diag_fill_geometry, + .start_IO = dasd_start_diag, + .term_IO = dasd_diag_term_IO, + .handle_terminated_request = dasd_diag_handle_terminated_request, + .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) { + pr_info("Discipline %s cannot be used without z/VM\n", + dasd_diag_discipline.name); + return -ENODEV; + } + ASCEBC(dasd_diag_discipline.ebcname, 4); + + irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL); + register_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler); + dasd_diag_discipline_pointer = &dasd_diag_discipline; + return 0; +} + +static void __exit +dasd_diag_cleanup(void) +{ + unregister_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler); + irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL); + dasd_diag_discipline_pointer = NULL; +} + +module_init(dasd_diag_init); +module_exit(dasd_diag_cleanup); |