/*- * Copyright (c) 1998 - 2005 Søren Schmidt * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer, * without modification, immediately at the beginning of the file. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include "opt_ata.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* prototypes */ static void ata_completed(void *, int); static void ata_timeout(struct ata_request *); static void ata_sort_queue(struct ata_channel *ch, struct ata_request *request); static char *ata_skey2str(u_int8_t); void ata_queue_request(struct ata_request *request) { struct ata_channel *ch = device_get_softc(device_get_parent(request->dev)); /* mark request as virgin */ request->result = request->status = request->error = 0; callout_init(&request->callout, 1); if (!request->callback && !(request->flags & ATA_R_REQUEUE)) sema_init(&request->done, 0, "ATA request done"); /* in ATA_STALL_QUEUE state we call HW directly (used only during reinit) */ if ((ch->state & ATA_STALL_QUEUE) && (request->flags & ATA_R_CONTROL)) { /* arm timeout */ if (!dumping) callout_reset(&request->callout, request->timeout * hz, (timeout_t*)ata_timeout, request); /* kick HW into action */ ch->running = request; if (ch->hw.begin_transaction(request) == ATA_OP_FINISHED) { ch->running = NULL; callout_drain(&request->callout); if (!request->callback) sema_destroy(&request->done); return; } } else { /* put request on the locked queue at the specified location */ mtx_lock(&ch->queue_mtx); if (request->flags & ATA_R_AT_HEAD) TAILQ_INSERT_HEAD(&ch->ata_queue, request, chain); else if (request->flags & ATA_R_ORDERED) ata_sort_queue(ch, request); else TAILQ_INSERT_TAIL(&ch->ata_queue, request, chain); mtx_unlock(&ch->queue_mtx); ATA_DEBUG_RQ(request, "queued"); ata_start(ch->dev); } /* if this is a requeued request callback/sleep has been setup */ if (request->flags & ATA_R_REQUEUE) return; /* if this is not a callback wait until request is completed */ if (!request->callback) { ATA_DEBUG_RQ(request, "wait for completition"); while (sema_timedwait(&request->done, request->timeout * hz * 4)) { device_printf(request->dev, "req=%p %s semaphore timeout !! DANGER Will Robinson !!\n", request, ata_cmd2str(request)); ata_start(ch->dev); } sema_destroy(&request->done); } } int ata_controlcmd(struct ata_device *atadev, u_int8_t command, u_int16_t feature, u_int64_t lba, u_int16_t count) { struct ata_request *request = ata_alloc_request(); int error = ENOMEM; if (request) { request->dev = atadev->dev; request->u.ata.command = command; request->u.ata.lba = lba; request->u.ata.count = count; request->u.ata.feature = feature; request->flags = ATA_R_CONTROL; request->timeout = 1; request->retries = 0; ata_queue_request(request); error = request->result; ata_free_request(request); } return error; } int ata_atapicmd(struct ata_device *atadev, u_int8_t *ccb, caddr_t data, int count, int flags, int timeout) { struct ata_request *request = ata_alloc_request(); int error = ENOMEM; if (request) { request->dev = atadev->dev; if ((atadev->param.config & ATA_PROTO_MASK) == ATA_PROTO_ATAPI_12) bcopy(ccb, request->u.atapi.ccb, 12); else bcopy(ccb, request->u.atapi.ccb, 16); request->data = data; request->bytecount = count; request->transfersize = min(request->bytecount, 65534); request->flags = flags | ATA_R_ATAPI; request->timeout = timeout; ata_queue_request(request); error = request->result; ata_free_request(request); } return error; } void ata_start(device_t dev) { struct ata_channel *ch = device_get_softc(dev); struct ata_request *request; struct ata_composite *cptr; int dependencies = 0; /* if we have a request on the queue try to get it running */ mtx_lock(&ch->queue_mtx); if ((request = TAILQ_FIRST(&ch->ata_queue))) { /* we need the locking function to get the lock for this channel */ if (ATA_LOCKING(dev, ATA_LF_LOCK) == ch->unit) { /* check for composite dependencies */ if ((cptr = request->composite)) { mtx_lock(&cptr->lock); if ((request->flags & ATA_R_WRITE) && (cptr->wr_depend & cptr->rd_done) != cptr->wr_depend) { dependencies = 1; } mtx_unlock(&cptr->lock); } /* check we are int the right state and has no dependencies */ mtx_lock(&ch->state_mtx); if (ch->state == ATA_IDLE && !dependencies) { ATA_DEBUG_RQ(request, "starting"); #if 0 if (request->sequence_count) request = request->sequence[--request->sequence_count]; else #else TAILQ_REMOVE(&ch->ata_queue, request, chain); #endif ch->running = request; ch->state = ATA_ACTIVE; /* if we are the freezing point release it */ if (ch->freezepoint == request) ch->freezepoint = NULL; /* arm timeout for this request */ if (!dumping) callout_reset(&request->callout, request->timeout * hz, (timeout_t*)ata_timeout, request); if (ch->hw.begin_transaction(request) == ATA_OP_FINISHED) { ch->running = NULL; ch->state = ATA_IDLE; mtx_unlock(&ch->state_mtx); mtx_unlock(&ch->queue_mtx); ATA_LOCKING(dev, ATA_LF_UNLOCK); ata_finish(request); return; } } mtx_unlock(&ch->state_mtx); } } mtx_unlock(&ch->queue_mtx); } void ata_finish(struct ata_request *request) { struct ata_channel *ch = device_get_softc(device_get_parent(request->dev)); /* if in STALL_QUEUE state or request is ATA_R_DIRECT call complete now */ if ((ch->state & ATA_STALL_QUEUE) || (request->flags & ATA_R_DIRECT)) { ATA_DEBUG_RQ(request, "finish directly"); ata_completed(request, 0); } else { /* reset timeout and put on the proper taskqueue for completition */ if (!dumping && !(request->flags & ATA_R_TIMEOUT)) callout_reset(&request->callout, request->timeout * hz, (timeout_t*)ata_timeout, request); if (request->bio && !(request->flags & (ATA_R_THREAD | ATA_R_TIMEOUT))){ ATA_DEBUG_RQ(request, "finish bio_taskqueue"); bio_taskqueue(request->bio, (bio_task_t *)ata_completed, request); } else { TASK_INIT(&request->task, 0, ata_completed, request); ATA_DEBUG_RQ(request, "finish taskqueue_swi"); taskqueue_enqueue(taskqueue_swi, &request->task); } } } static void ata_completed(void *context, int dummy) { struct ata_request *request = (struct ata_request *)context; struct ata_channel *ch = device_get_softc(device_get_parent(request->dev)); struct ata_device *atadev = device_get_softc(request->dev); struct ata_composite *composite; ATA_DEBUG_RQ(request, "completed entered"); /* if we had a timeout, reinit channel and deal with the falldown */ if (request->flags & ATA_R_TIMEOUT) { /* * if reinit succeeds, retries still permit and device didn't * get removed by the reinit, reinject request */ if (!ata_reinit(ch->dev) && request->dev && (request->retries-- > 0)) { request->flags &= ~(ATA_R_TIMEOUT | ATA_R_DEBUG); request->flags |= (ATA_R_AT_HEAD | ATA_R_REQUEUE); ATA_DEBUG_RQ(request, "completed reinject"); ata_queue_request(request); return; } /* nothing more to try so finish with error */ if (!(request->flags & ATA_R_QUIET)) { if (request->dev) { device_printf(request->dev, "FAILURE - %s timed out", ata_cmd2str(request)); if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL))) printf(" LBA=%llu", (unsigned long long)request->u.ata.lba); printf("\n"); } } if (!request->result) request->result = EIO; } else { /* untimeout request now we have control back */ callout_drain(&request->callout); /* if this is a soft ECC error warn about it */ if ((request->status & (ATA_S_CORR | ATA_S_ERROR)) == ATA_S_CORR) { device_printf(request->dev, "WARNING - %s soft error (ECC corrected)", ata_cmd2str(request)); if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL))) printf(" LBA=%llu", (unsigned long long)request->u.ata.lba); printf("\n"); } /* if this is a UDMA CRC error, retry request */ if (request->flags & ATA_R_DMA && request->error & ATA_E_ICRC) { if (request->retries-- > 0) { device_printf(request->dev, "WARNING - %s UDMA ICRC error (retrying request)", ata_cmd2str(request)); if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL))) printf(" LBA=%llu", (unsigned long long)request->u.ata.lba); printf("\n"); request->flags |= (ATA_R_AT_HEAD | ATA_R_REQUEUE); ata_queue_request(request); return; } } } switch (request->flags & ATA_R_ATAPI) { /* ATA errors */ default: if (!request->result && request->status & ATA_S_ERROR) { if (!(request->flags & ATA_R_QUIET)) { device_printf(request->dev, "FAILURE - %s status=%b error=%b", ata_cmd2str(request), request->status, "\20\10BUSY\7READY\6DMA_READY" "\5DSC\4DRQ\3CORRECTABLE\2INDEX\1ERROR", request->error, "\20\10ICRC\7UNCORRECTABLE" "\6MEDIA_CHANGED\5NID_NOT_FOUND" "\4MEDIA_CHANGE_REQEST" "\3ABORTED\2NO_MEDIA\1ILLEGAL_LENGTH"); if ((request->flags & ATA_R_DMA) && (request->dmastat & ATA_BMSTAT_ERROR)) printf(" dma=0x%02x", request->dmastat); if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL))) printf(" LBA=%llu", (unsigned long long)request->u.ata.lba); printf("\n"); } request->result = EIO; } break; /* ATAPI errors */ case ATA_R_ATAPI: /* skip if result already set */ if (request->result) break; /* if we have a sensekey -> request sense from device */ if (request->error & ATA_SK_MASK && request->u.atapi.ccb[0] != ATAPI_REQUEST_SENSE) { static u_int8_t ccb[16] = { ATAPI_REQUEST_SENSE, 0, 0, 0, sizeof(struct atapi_sense), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; request->u.atapi.sense_key = request->error; request->u.atapi.sense_cmd = request->u.atapi.ccb[0]; bcopy(ccb, request->u.atapi.ccb, 16); request->data = (caddr_t)&request->u.atapi.sense_data; request->bytecount = sizeof(struct atapi_sense); request->transfersize = sizeof(struct atapi_sense); request->timeout = 5; request->flags &= (ATA_R_ATAPI | ATA_R_QUIET); request->flags |= (ATA_R_READ | ATA_R_AT_HEAD | ATA_R_REQUEUE); ATA_DEBUG_RQ(request, "autoissue request sense"); ata_queue_request(request); return; } switch (request->u.atapi.sense_key & ATA_SK_MASK) { case ATA_SK_RECOVERED_ERROR: device_printf(request->dev, "WARNING - %s recovered error\n", ata_cmd2str(request)); /* FALLTHROUGH */ case ATA_SK_NO_SENSE: request->result = 0; break; case ATA_SK_NOT_READY: request->result = EBUSY; break; case ATA_SK_UNIT_ATTENTION: atadev->flags |= ATA_D_MEDIA_CHANGED; request->result = EIO; break; default: request->result = EIO; if (request->flags & ATA_R_QUIET) break; device_printf(request->dev, "FAILURE - %s %s asc=0x%02x ascq=0x%02x ", ata_cmd2str(request), ata_skey2str( (request->u.atapi.sense_key & ATA_SK_MASK) >> 4), request->u.atapi.sense_data.asc, request->u.atapi.sense_data.ascq); if (request->u.atapi.sense_data.sksv) printf("sks=0x%02x 0x%02x 0x%02x ", request->u.atapi.sense_data.sk_specific, request->u.atapi.sense_data.sk_specific1, request->u.atapi.sense_data.sk_specific2); printf("error=%b\n", (request->u.atapi.sense_key & ATA_E_MASK), "\20\4MEDIA_CHANGE_REQUEST\3ABORTED" "\2NO_MEDIA\1ILLEGAL_LENGTH"); } if ((request->u.atapi.sense_key ? request->u.atapi.sense_key : request->error) & ATA_E_MASK) request->result = EIO; } ATA_DEBUG_RQ(request, "completed callback/wakeup"); /* if we are part of a composite operation update progress */ if ((composite = request->composite)) { int index = 0; mtx_lock(&composite->lock); if (request->flags & ATA_R_READ) composite->rd_done |= (1 << request->this); if (request->flags & ATA_R_WRITE) composite->wr_done |= (1 << request->this); if (composite->wr_depend && (composite->rd_done & composite->wr_depend)==composite->wr_depend && (composite->wr_needed & (~composite->wr_done))) { index = ((composite->wr_needed & (~composite->wr_done))) - 1; } mtx_unlock(&composite->lock); if (index) ata_start(device_get_parent(composite->request[index]->dev)); } /* get results back to the initiator */ if (request->callback) (request->callback)(request); else sema_post(&request->done); ata_start(ch->dev); } static void ata_timeout(struct ata_request *request) { struct ata_channel *ch = device_get_softc(device_get_parent(request->dev)); mtx_lock(&ch->state_mtx); //request->flags |= ATA_R_DEBUG; ATA_DEBUG_RQ(request, "timeout"); /* if interrupt has been seen, shout and just rearm timeout */ if (request->flags & ATA_R_INTR_SEEN) { device_printf(request->dev, "WARNING - %s interrupt was seen but timeout fired", ata_cmd2str(request)); if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL))) printf(" LBA=%llu", (unsigned long long)request->u.ata.lba); printf("\n"); /* re-arm timeout */ if (!dumping) callout_reset(&request->callout, request->timeout * hz, (timeout_t*)ata_timeout, request); mtx_unlock(&ch->state_mtx); return; } /* * grap and hold the state lock so we wont loose the race with * an eventual interrupt arriving late */ if (ch->state == ATA_ACTIVE || ch->state == ATA_STALL_QUEUE) { request->flags |= ATA_R_TIMEOUT; if (!(request->flags & ATA_R_QUIET) && request->retries > 0) { device_printf(request->dev, "TIMEOUT - %s retrying (%d retr%s left)", ata_cmd2str(request), request->retries, request->retries == 1 ? "y" : "ies"); if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL))) printf(" LBA=%llu", (unsigned long long)request->u.ata.lba); printf("\n"); } ch->hw.end_transaction(request); ch->state |= ATA_TIMEOUT; mtx_unlock(&ch->state_mtx); ATA_LOCKING(ch->dev, ATA_LF_UNLOCK); ata_finish(request); } else { mtx_unlock(&ch->state_mtx); device_printf(request->dev, "timeout state=%d unexpected\n", ch->state); } } void ata_catch_inflight(struct ata_channel *ch) { struct ata_request *request; mtx_lock(&ch->state_mtx); request = ch->running; ch->running = NULL; mtx_unlock(&ch->state_mtx); if (request) { callout_drain(&request->callout); device_printf(request->dev, "WARNING - %s requeued due to channel reset", ata_cmd2str(request)); if (!(request->flags & (ATA_R_ATAPI | ATA_R_CONTROL))) printf(" LBA=%llu", (unsigned long long)request->u.ata.lba); printf("\n"); request->flags |= ATA_R_REQUEUE; ata_queue_request(request); } } void ata_fail_requests(struct ata_channel *ch, device_t dev) { struct ata_request *request; /* fail all requests queued on this channel for device dev if !NULL */ mtx_lock(&ch->queue_mtx); while ((request = TAILQ_FIRST(&ch->ata_queue))) { if (!dev || request->dev == dev) { TAILQ_REMOVE(&ch->ata_queue, request, chain); mtx_unlock(&ch->queue_mtx); request->result = ENXIO; ata_finish(request); mtx_lock(&ch->queue_mtx); } } mtx_unlock(&ch->queue_mtx); mtx_lock(&ch->state_mtx); request = ch->running; ch->running = NULL; mtx_unlock(&ch->state_mtx); /* if we have a request "in flight" fail it as well */ if (request && (!dev || request->dev == dev)) { callout_drain(&request->callout); request->result = ENXIO; ata_finish(request); } } static u_int64_t ata_get_lba(struct ata_request *request) { if (request->flags & ATA_R_ATAPI) { switch (request->u.atapi.ccb[0]) { case ATAPI_READ_BIG: case ATAPI_WRITE_BIG: case ATAPI_READ_CD: return (request->u.atapi.ccb[5]) | (request->u.atapi.ccb[4]<<8) | (request->u.atapi.ccb[3]<<16)|(request->u.atapi.ccb[2]<<24); case ATAPI_READ: case ATAPI_WRITE: return (request->u.atapi.ccb[4]) | (request->u.atapi.ccb[3]<<8) | (request->u.atapi.ccb[2]<<16); default: return 0; } } else return request->u.ata.lba; } static void ata_sort_queue(struct ata_channel *ch, struct ata_request *request) { struct ata_request *this, *next; this = TAILQ_FIRST(&ch->ata_queue); /* if the queue is empty just insert */ if (!this) { if (request->composite) ch->freezepoint = request; TAILQ_INSERT_TAIL(&ch->ata_queue, request, chain); return; } /* dont sort frozen parts of the queue */ if (ch->freezepoint) this = ch->freezepoint; /* if position is less than head we add after tipping point */ if (ata_get_lba(request) < ata_get_lba(this)) { while ((next = TAILQ_NEXT(this, chain))) { /* have we reached the tipping point */ if (ata_get_lba(next) < ata_get_lba(this)) { /* sort the insert */ do { if (ata_get_lba(request) < ata_get_lba(next)) break; this = next; } while ((next = TAILQ_NEXT(this, chain))); break; } this = next; } } /* we are after head so sort the insert before tipping point */ else { while ((next = TAILQ_NEXT(this, chain))) { if (ata_get_lba(next) < ata_get_lba(this) || ata_get_lba(request) < ata_get_lba(next)) break; this = next; } } if (request->composite) ch->freezepoint = request; TAILQ_INSERT_AFTER(&ch->ata_queue, this, request, chain); } char * ata_cmd2str(struct ata_request *request) { static char buffer[20]; if (request->flags & ATA_R_ATAPI) { switch (request->u.atapi.sense_key ? request->u.atapi.sense_cmd : request->u.atapi.ccb[0]) { case 0x00: return ("TEST_UNIT_READY"); case 0x01: return ("REZERO"); case 0x03: return ("REQUEST_SENSE"); case 0x04: return ("FORMAT"); case 0x08: return ("READ"); case 0x0a: return ("WRITE"); case 0x10: return ("WEOF"); case 0x11: return ("SPACE"); case 0x12: return ("INQUIRY"); case 0x15: return ("MODE_SELECT"); case 0x19: return ("ERASE"); case 0x1a: return ("MODE_SENSE"); case 0x1b: return ("START_STOP"); case 0x1e: return ("PREVENT_ALLOW"); case 0x23: return ("ATAPI_READ_FORMAT_CAPACITIES"); case 0x25: return ("READ_CAPACITY"); case 0x28: return ("READ_BIG"); case 0x2a: return ("WRITE_BIG"); case 0x2b: return ("LOCATE"); case 0x34: return ("READ_POSITION"); case 0x35: return ("SYNCHRONIZE_CACHE"); case 0x3b: return ("WRITE_BUFFER"); case 0x3c: return ("READ_BUFFER"); case 0x42: return ("READ_SUBCHANNEL"); case 0x43: return ("READ_TOC"); case 0x45: return ("PLAY_10"); case 0x47: return ("PLAY_MSF"); case 0x48: return ("PLAY_TRACK"); case 0x4b: return ("PAUSE"); case 0x51: return ("READ_DISK_INFO"); case 0x52: return ("READ_TRACK_INFO"); case 0x53: return ("RESERVE_TRACK"); case 0x54: return ("SEND_OPC_INFO"); case 0x55: return ("MODE_SELECT_BIG"); case 0x58: return ("REPAIR_TRACK"); case 0x59: return ("READ_MASTER_CUE"); case 0x5a: return ("MODE_SENSE_BIG"); case 0x5b: return ("CLOSE_TRACK/SESSION"); case 0x5c: return ("READ_BUFFER_CAPACITY"); case 0x5d: return ("SEND_CUE_SHEET"); case 0xa1: return ("BLANK_CMD"); case 0xa3: return ("SEND_KEY"); case 0xa4: return ("REPORT_KEY"); case 0xa5: return ("PLAY_12"); case 0xa6: return ("LOAD_UNLOAD"); case 0xad: return ("READ_DVD_STRUCTURE"); case 0xb4: return ("PLAY_CD"); case 0xbb: return ("SET_SPEED"); case 0xbd: return ("MECH_STATUS"); case 0xbe: return ("READ_CD"); case 0xff: return ("POLL_DSC"); } } else { switch (request->u.ata.command) { case 0x00: return ("NOP"); case 0x08: return ("DEVICE_RESET"); case 0x20: return ("READ"); case 0x24: return ("READ48"); case 0x25: return ("READ_DMA48"); case 0x26: return ("READ_DMA_QUEUED48"); case 0x29: return ("READ_MUL48"); case 0x30: return ("WRITE"); case 0x34: return ("WRITE48"); case 0x35: return ("WRITE_DMA48"); case 0x36: return ("WRITE_DMA_QUEUED48"); case 0x39: return ("WRITE_MUL48"); case 0x70: return ("SEEK"); case 0xa0: return ("PACKET_CMD"); case 0xa1: return ("ATAPI_IDENTIFY"); case 0xa2: return ("SERVICE"); case 0xc4: return ("READ_MUL"); case 0xc5: return ("WRITE_MUL"); case 0xc6: return ("SET_MULTI"); case 0xc7: return ("READ_DMA_QUEUED"); case 0xc8: return ("READ_DMA"); case 0xca: return ("WRITE_DMA"); case 0xcc: return ("WRITE_DMA_QUEUED"); case 0xe6: return ("SLEEP"); case 0xe7: return ("FLUSHCACHE"); case 0xea: return ("FLUSHCACHE48"); case 0xec: return ("ATA_IDENTIFY"); case 0xef: switch (request->u.ata.feature) { case 0x03: return ("SETFEATURES SET TRANSFER MODE"); case 0x02: return ("SETFEATURES ENABLE WCACHE"); case 0x82: return ("SETFEATURES DISABLE WCACHE"); case 0xaa: return ("SETFEATURES ENABLE RCACHE"); case 0x55: return ("SETFEATURES DISABLE RCACHE"); } sprintf(buffer, "SETFEATURES 0x%02x", request->u.ata.feature); return buffer; } } sprintf(buffer, "unknown CMD (0x%02x)", request->u.ata.command); return buffer; } static char * ata_skey2str(u_int8_t skey) { switch (skey) { case 0x00: return ("NO SENSE"); case 0x01: return ("RECOVERED ERROR"); case 0x02: return ("NOT READY"); case 0x03: return ("MEDIUM ERROR"); case 0x04: return ("HARDWARE ERROR"); case 0x05: return ("ILLEGAL REQUEST"); case 0x06: return ("UNIT ATTENTION"); case 0x07: return ("DATA PROTECT"); case 0x08: return ("BLANK CHECK"); case 0x09: return ("VENDOR SPECIFIC"); case 0x0a: return ("COPY ABORTED"); case 0x0b: return ("ABORTED COMMAND"); case 0x0c: return ("EQUAL"); case 0x0d: return ("VOLUME OVERFLOW"); case 0x0e: return ("MISCOMPARE"); case 0x0f: return ("RESERVED"); default: return("UNKNOWN"); } }