// SPDX-License-Identifier: GPL-2.0 /* * 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/diag.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; } static inline int dia250(void *iob, int cmd) { diag_stat_inc(DIAG_STAT_X250); return __dia250(iob, cmd); } /* 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 = device->private; struct dasd_diag_init_io *iib = &private->iib; int rc; 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 = device->private; struct dasd_diag_init_io *iib = &private->iib; int rc; 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_warn("%s: The access mode of a DIAG device changed to read-only\n", dev_name(&device->cdev->dev)); rc = 0; } if (rc) pr_warn("%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 = device->private; dreq = 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 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_diag_private *private = device->private; struct dasd_diag_characteristics *rdc_data; struct vtoc_cms_label *label; struct dasd_block *block; struct dasd_diag_bio bio; unsigned int sb, bsize; blocknum_t end_block; int rc; if (private == NULL) { private = kzalloc(sizeof(*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 = 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 = &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_warn("%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_warn("%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_warn("%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_warn("%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 = device->private; info->label_block = (unsigned int) private->pt_block; info->FBA_layout = 1; info->format = DASD_FORMAT_LDL; info->characteristics_size = sizeof(private->rdc_data); memcpy(info->characteristics, &private->rdc_data, sizeof(private->rdc_data)); 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);