/* * linux/drivers/scsi/ide-scsi.c Version 0.2 - ALPHA Jan 26, 1997 * * Copyright (C) 1996, 1997 Gadi Oxman */ /* * Emulation of a SCSI host adapter for IDE ATAPI devices. * * With this driver, one can use the Linux SCSI drivers instead of the * native IDE ATAPI drivers. * * Ver 0.1 Dec 3 96 Initial version. * Ver 0.2 Jan 26 97 Fixed bug in cleanup_module() and added emulation * of MODE_SENSE_6/MODE_SELECT_6 for cdroms. Thanks * to Janos Farkas for pointing this out. * Avoid using bitfields in structures for m68k. * Added Scather/Gather and DMA support. */ #include #include #include #include #include #include #include #include #include #include #include #include #include "../block/ide.h" #include "scsi.h" #include "hosts.h" #include "sd.h" #include "ide-scsi.h" #define IDESCSI_DEBUG_LOG 0 typedef struct idescsi_pc_s { u8 c[12]; /* Actual packet bytes */ int request_transfer; /* Bytes to transfer */ int actually_transferred; /* Bytes actually transferred */ int buffer_size; /* Size of our data buffer */ struct request *rq; /* The corresponding request */ byte *buffer; /* Data buffer */ byte *current_position; /* Pointer into the above buffer */ struct scatterlist *sg; /* Scather gather table */ int b_count; /* Bytes transferred from current entry */ Scsi_Cmnd *scsi_cmd; /* SCSI command */ void (*done)(Scsi_Cmnd *); /* Scsi completion routine */ unsigned int flags; /* Status/Action flags */ } idescsi_pc_t; /* * Packet command status bits. */ #define PC_DMA_IN_PROGRESS 0 /* 1 while DMA in progress */ #define PC_WRITING 1 /* Data direction */ typedef struct { ide_drive_t *drive; idescsi_pc_t *pc; /* Current packet command */ unsigned int flags; /* Status/Action flags */ } idescsi_scsi_t; /* * Per ATAPI device status bits. */ #define IDESCSI_DRQ_INTERRUPT 0 /* DRQ interrupt device */ /* * ide-scsi requests. */ #define IDESCSI_PC_RQ 90 /* * Bits of the interrupt reason register. */ #define IDESCSI_IREASON_COD 0x1 /* Information transferred is command */ #define IDESCSI_IREASON_IO 0x2 /* The device requests us to read */ static void idescsi_discard_data (ide_drive_t *drive, unsigned int bcount) { while (bcount--) IN_BYTE (IDE_DATA_REG); } static void idescsi_output_zeros (ide_drive_t *drive, unsigned int bcount) { while (bcount--) OUT_BYTE (0, IDE_DATA_REG); } /* * PIO data transfer routines using the scather gather table. */ static void idescsi_input_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount) { int count; while (bcount) { if (pc->sg - (struct scatterlist *) pc->scsi_cmd->request_buffer > pc->scsi_cmd->use_sg) { printk (KERN_ERR "ide-scsi: scather gather table too small, discarding data\n"); idescsi_discard_data (drive, bcount); return; } count = IDE_MIN (pc->sg->length - pc->b_count, bcount); atapi_input_bytes (drive, pc->sg->address + pc->b_count, count); bcount -= count; pc->b_count += count; if (pc->b_count == pc->sg->length) { pc->sg++; pc->b_count = 0; } } } static void idescsi_output_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount) { int count; while (bcount) { if (pc->sg - (struct scatterlist *) pc->scsi_cmd->request_buffer > pc->scsi_cmd->use_sg) { printk (KERN_ERR "ide-scsi: scather gather table too small, padding with zeros\n"); idescsi_output_zeros (drive, bcount); return; } count = IDE_MIN (pc->sg->length - pc->b_count, bcount); atapi_output_bytes (drive, pc->sg->address + pc->b_count, count); bcount -= count; pc->b_count += count; if (pc->b_count == pc->sg->length) { pc->sg++; pc->b_count = 0; } } } /* * Most of the SCSI commands are supported directly by ATAPI devices. * idescsi_transform_pc handles the few exceptions. */ static inline void idescsi_transform_pc1 (ide_drive_t *drive, idescsi_pc_t *pc) { u8 *c = pc->c, *buf = pc->buffer, *sc = pc->scsi_cmd->cmnd; int i; if (drive->media == ide_cdrom) { if (c[0] == READ_6) { c[8] = c[4]; c[5] = c[3]; c[4] = c[2]; c[3] = c[1] & 0x1f; c[2] = 0; c[1] &= 0xe0; c[0] = READ_10; } if (c[0] == MODE_SENSE || (c[0] == MODE_SELECT && buf[3] == 8)) { pc->request_transfer -= 4; memset (c, 0, 12); c[0] = sc[0] | 0x40; c[2] = sc[2]; c[8] = sc[4] - 4; if (c[0] == MODE_SENSE_10) return; for (i = 0; i <= 7; i++) buf[i] = 0; for (i = 8; i < pc->buffer_size - 4; i++) buf[i] = buf[i + 4]; } } } static inline void idescsi_transform_pc2 (ide_drive_t *drive, idescsi_pc_t *pc) { u8 *buf = pc->buffer; int i; if (drive->media == ide_cdrom) { if (pc->c[0] == MODE_SENSE_10 && pc->scsi_cmd->cmnd[0] == MODE_SENSE) { buf[0] = buf[1]; buf[1] = buf[2]; buf[2] = 0; buf[3] = 8; for (i = pc->buffer_size - 1; i >= 12; i--) buf[i] = buf[i - 4]; for (i = 11; i >= 4; i--) buf[i] = 0; } } } static inline void idescsi_free_bh (struct buffer_head *bh) { struct buffer_head *bhp; while (bh) { bhp = bh; bh = bh->b_reqnext; kfree (bhp); } } static void idescsi_end_request (byte uptodate, ide_hwgroup_t *hwgroup) { ide_drive_t *drive = hwgroup->drive; idescsi_scsi_t *scsi = drive->driver_data; struct request *rq = hwgroup->rq; idescsi_pc_t *pc = (idescsi_pc_t *) rq->buffer; if (rq->cmd != IDESCSI_PC_RQ) { ide_end_request (uptodate, hwgroup); return; } ide_end_drive_cmd (drive, 0, 0); if (rq->errors >= ERROR_MAX) { #if IDESCSI_DEBUG_LOG printk ("ide-scsi: %s: I/O error for %lu\n", drive->name, pc->scsi_cmd->serial_number); #endif /* IDESCSI_DEBUG_LOG */ pc->scsi_cmd->result = DID_ERROR << 16; } else if (rq->errors) { #if IDESCSI_DEBUG_LOG printk ("ide-scsi: %s: check condition for %lu\n", drive->name, pc->scsi_cmd->serial_number); #endif /* IDESCSI_DEBUG_LOG */ pc->scsi_cmd->result = (CHECK_CONDITION << 1) | (DID_OK << 16); } else { #if IDESCSI_DEBUG_LOG printk ("ide-scsi: %s: success for %lu\n", drive->name, pc->scsi_cmd->serial_number); #endif /* IDESCSI_DEBUG_LOG */ pc->scsi_cmd->result = DID_OK << 16; idescsi_transform_pc2 (drive, pc); } pc->done(pc->scsi_cmd); idescsi_free_bh (rq->bh); kfree(pc); kfree(rq); scsi->pc = NULL; } /* * Our interrupt handler. */ static void idescsi_pc_intr (ide_drive_t *drive) { idescsi_scsi_t *scsi = drive->driver_data; byte status, ireason; int bcount; idescsi_pc_t *pc=scsi->pc; struct request *rq = pc->rq; unsigned int temp; #if IDESCSI_DEBUG_LOG printk (KERN_INFO "ide-scsi: Reached idescsi_pc_intr interrupt handler\n"); #endif /* IDESCSI_DEBUG_LOG */ if (test_and_clear_bit (PC_DMA_IN_PROGRESS, &pc->flags)) { #if IDESCSI_DEBUG_LOG printk ("ide-scsi: %s: DMA complete\n", drive->name); #endif /* IDESCSI_DEBUG_LOG */ pc->actually_transferred=pc->request_transfer; (void) (HWIF(drive)->dmaproc(ide_dma_abort, drive)); } status = GET_STAT(); /* Clear the interrupt */ if ((status & DRQ_STAT) == 0) { /* No more interrupts */ #if IDESCSI_DEBUG_LOG printk (KERN_INFO "Packet command completed, %d bytes transferred\n", pc->actually_transferred); #endif /* IDESCSI_DEBUG_LOG */ ide_sti(); if (status & ERR_STAT) rq->errors++; idescsi_end_request (1, HWGROUP(drive)); return; } bcount = IN_BYTE (IDE_BCOUNTH_REG) << 8 | IN_BYTE (IDE_BCOUNTL_REG); ireason = IN_BYTE (IDE_IREASON_REG); if (ireason & IDESCSI_IREASON_COD) { printk (KERN_ERR "ide-scsi: CoD != 0 in idescsi_pc_intr\n"); ide_do_reset (drive); return; } if (ireason & IDESCSI_IREASON_IO) { temp = pc->actually_transferred + bcount; if ( temp > pc->request_transfer) { if (temp > pc->buffer_size) { printk (KERN_ERR "ide-scsi: The scsi wants to send us more data than expected - discarding data\n"); idescsi_discard_data (drive,bcount); ide_set_handler (drive,&idescsi_pc_intr,WAIT_CMD); return; } #if IDESCSI_DEBUG_LOG printk (KERN_NOTICE "ide-scsi: The scsi wants to send us more data than expected - allowing transfer\n"); #endif /* IDESCSI_DEBUG_LOG */ } } if (ireason & IDESCSI_IREASON_IO) { if (pc->sg) idescsi_input_buffers (drive, pc, bcount); else atapi_input_bytes (drive,pc->current_position,bcount); } else { if (pc->sg) idescsi_output_buffers (drive, pc, bcount); else atapi_output_bytes (drive,pc->current_position,bcount); } pc->actually_transferred+=bcount; /* Update the current position */ pc->current_position+=bcount; ide_set_handler (drive,&idescsi_pc_intr,WAIT_CMD); /* And set the interrupt handler again */ } static void idescsi_transfer_pc (ide_drive_t *drive) { idescsi_scsi_t *scsi = drive->driver_data; byte ireason; if (ide_wait_stat (drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) { printk (KERN_ERR "ide-scsi: Strange, packet command initiated yet DRQ isn't asserted\n"); return; } ireason = IN_BYTE (IDE_IREASON_REG); if ((ireason & (IDESCSI_IREASON_IO | IDESCSI_IREASON_COD)) != IDESCSI_IREASON_COD) { printk (KERN_ERR "ide-scsi: (IO,CoD) != (0,1) while issuing a packet command\n"); ide_do_reset (drive); return; } ide_set_handler (drive, &idescsi_pc_intr, WAIT_CMD); /* Set the interrupt routine */ atapi_output_bytes (drive, scsi->pc->c, 12); /* Send the actual packet */ } /* * Issue a packet command */ static void idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc) { idescsi_scsi_t *scsi = drive->driver_data; int bcount; struct request *rq = pc->rq; int dma_ok = 0; scsi->pc=pc; /* Set the current packet command */ pc->actually_transferred=0; /* We haven't transferred any data yet */ pc->current_position=pc->buffer; bcount = IDE_MIN (pc->request_transfer, 63 * 1024); /* Request to transfer the entire buffer at once */ if (drive->using_dma && rq->bh) dma_ok=!HWIF(drive)->dmaproc(test_bit (PC_WRITING, &pc->flags) ? ide_dma_write : ide_dma_read, drive); OUT_BYTE (drive->ctl,IDE_CONTROL_REG); OUT_BYTE (dma_ok,IDE_FEATURE_REG); OUT_BYTE (bcount >> 8,IDE_BCOUNTH_REG); OUT_BYTE (bcount & 0xff,IDE_BCOUNTL_REG); OUT_BYTE (drive->select.all,IDE_SELECT_REG); if (dma_ok) { set_bit (PC_DMA_IN_PROGRESS, &pc->flags); (void) (HWIF(drive)->dmaproc(ide_dma_begin, drive)); } if (test_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags)) { ide_set_handler (drive, &idescsi_transfer_pc, WAIT_CMD); OUT_BYTE (WIN_PACKETCMD, IDE_COMMAND_REG); /* Issue the packet command */ } else { OUT_BYTE (WIN_PACKETCMD, IDE_COMMAND_REG); idescsi_transfer_pc (drive); } } /* * idescsi_do_request is our request handling function. */ static void idescsi_do_request (ide_drive_t *drive, struct request *rq, unsigned long block) { #if IDESCSI_DEBUG_LOG printk (KERN_INFO "rq_status: %d, rq_dev: %u, cmd: %d, errors: %d\n",rq->rq_status,(unsigned int) rq->rq_dev,rq->cmd,rq->errors); printk (KERN_INFO "sector: %ld, nr_sectors: %ld, current_nr_sectors: %ld\n",rq->sector,rq->nr_sectors,rq->current_nr_sectors); #endif /* IDESCSI_DEBUG_LOG */ if (rq->cmd == IDESCSI_PC_RQ) { idescsi_issue_pc (drive, (idescsi_pc_t *) rq->buffer); return; } printk (KERN_ERR "ide-scsi: %s: unsupported command in request queue (%x)\n", drive->name, rq->cmd); idescsi_end_request (0,HWGROUP (drive)); } static int idescsi_open (struct inode *inode, struct file *filp, ide_drive_t *drive) { MOD_INC_USE_COUNT; return 0; } static void idescsi_ide_release (struct inode *inode, struct file *filp, ide_drive_t *drive) { MOD_DEC_USE_COUNT; } static ide_drive_t *idescsi_drives[MAX_HWIFS * MAX_DRIVES]; static int idescsi_initialized = 0; /* * Driver initialization. */ static void idescsi_setup (ide_drive_t *drive, idescsi_scsi_t *scsi, int id) { DRIVER(drive)->busy++; idescsi_drives[id] = drive; drive->driver_data = scsi; drive->ready_stat = 0; memset (scsi, 0, sizeof (idescsi_scsi_t)); scsi->drive = drive; if (drive->id && (drive->id->config & 0x0060) == 0x20) set_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags); } static int idescsi_cleanup (ide_drive_t *drive) { idescsi_scsi_t *scsi = drive->driver_data; if (ide_unregister_subdriver (drive)) return 1; drive->driver_data = NULL; kfree (scsi); return 0; } int idescsi_init (void); static ide_module_t idescsi_module = { IDE_DRIVER_MODULE, idescsi_init, NULL }; /* * IDE subdriver functions, registered with ide.c */ static ide_driver_t idescsi_driver = { ide_scsi, /* media */ 0, /* busy */ 1, /* supports_dma */ 0, /* supports_dsc_overlap */ idescsi_cleanup, /* cleanup */ idescsi_do_request, /* do_request */ idescsi_end_request, /* end_request */ NULL, /* ioctl */ idescsi_open, /* open */ idescsi_ide_release, /* release */ NULL, /* media_change */ NULL, /* pre_reset */ NULL, /* capacity */ NULL /* special */ }; static struct proc_dir_entry idescsi_proc_dir = {PROC_SCSI_IDESCSI, 8, "ide-scsi", S_IFDIR | S_IRUGO | S_IXUGO, 2}; /* * idescsi_init will register the driver for each scsi. */ int idescsi_init (void) { ide_drive_t *drive; idescsi_scsi_t *scsi; byte media[] = {TYPE_DISK, TYPE_TAPE, TYPE_PROCESSOR, TYPE_WORM, TYPE_ROM, TYPE_SCANNER, TYPE_MOD, 255}; int i, failed, id; if (idescsi_initialized) return 0; idescsi_initialized = 1; for (i = 0; i < MAX_HWIFS * MAX_DRIVES; i++) idescsi_drives[i] = NULL; MOD_INC_USE_COUNT; for (i = 0; media[i] != 255; i++) { failed = 0; while ((drive = ide_scan_devices (media[i], NULL, failed++)) != NULL) { if ((scsi = (idescsi_scsi_t *) kmalloc (sizeof (idescsi_scsi_t), GFP_KERNEL)) == NULL) { printk (KERN_ERR "ide-scsi: %s: Can't allocate a scsi structure\n", drive->name); continue; } if (ide_register_subdriver (drive, &idescsi_driver, IDE_SUBDRIVER_VERSION)) { printk (KERN_ERR "ide-scsi: %s: Failed to register the driver with ide.c\n", drive->name); kfree (scsi); continue; } for (id = 0; id < MAX_HWIFS * MAX_DRIVES && idescsi_drives[id]; id++); idescsi_setup (drive, scsi, id); failed--; } } ide_register_module(&idescsi_module); MOD_DEC_USE_COUNT; return 0; } int idescsi_detect (Scsi_Host_Template *host_template) { struct Scsi_Host *host; int id; host_template->proc_dir = &idescsi_proc_dir; host = scsi_register(host_template, 0); for (id = 0; id < MAX_HWIFS * MAX_DRIVES && idescsi_drives[id]; id++); host->max_id = id; host->can_queue = host->cmd_per_lun * id; return 1; } int idescsi_release (struct Scsi_Host *host) { ide_drive_t *drive; int id; for (id = 0; id < MAX_HWIFS * MAX_DRIVES; id++) { drive = idescsi_drives[id]; if (drive) DRIVER(drive)->busy--; } return 0; } const char *idescsi_info (struct Scsi_Host *host) { return "SCSI host adapter emulation for IDE ATAPI devices"; } static inline struct buffer_head *idescsi_kmalloc_bh (int count) { struct buffer_head *bh, *bhp, *first_bh; if ((first_bh = bhp = bh = kmalloc (sizeof(struct buffer_head), GFP_ATOMIC)) == NULL) goto abort; memset (bh, 0, sizeof (struct buffer_head)); bh->b_reqnext = NULL; while (--count) { if ((bh = kmalloc (sizeof(struct buffer_head), GFP_ATOMIC)) == NULL) goto abort; memset (bh, 0, sizeof (struct buffer_head)); bhp->b_reqnext = bh; bhp = bh; bh->b_reqnext = NULL; } return first_bh; abort: idescsi_free_bh (first_bh); return NULL; } static inline int idescsi_set_direction (idescsi_pc_t *pc) { switch (pc->c[0]) { case READ_6: case READ_10: case READ_12: clear_bit (PC_WRITING, &pc->flags); return 0; case WRITE_6: case WRITE_10: case WRITE_12: set_bit (PC_WRITING, &pc->flags); return 0; default: return 1; } } static inline struct buffer_head *idescsi_dma_bh (ide_drive_t *drive, idescsi_pc_t *pc) { struct buffer_head *bh = NULL, *first_bh = NULL; int segments = pc->scsi_cmd->use_sg; struct scatterlist *sg = pc->scsi_cmd->request_buffer; if (!drive->using_dma || pc->request_transfer % 1024) return NULL; if (idescsi_set_direction(pc)) return NULL; if (segments) { if ((first_bh = bh = idescsi_kmalloc_bh (segments)) == NULL) return NULL; #if IDESCSI_DEBUG_LOG printk ("ide-scsi: %s: building DMA table, %d segments, %dkB total\n", drive->name, segments, pc->request_transfer >> 10); #endif /* IDESCSI_DEBUG_LOG */ while (segments--) { bh->b_data = sg->address; bh->b_size = sg->length; bh = bh->b_reqnext; sg++; } } else { if ((first_bh = bh = idescsi_kmalloc_bh (1)) == NULL) return NULL; #if IDESCSI_DEBUG_LOG printk ("ide-scsi: %s: building DMA table for a single buffer (%dkB)\n", drive->name, pc->request_transfer >> 10); #endif /* IDESCSI_DEBUG_LOG */ bh->b_data = pc->scsi_cmd->request_buffer; bh->b_size = pc->request_transfer; } return first_bh; } int idescsi_queue (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *)) { ide_drive_t *drive = idescsi_drives[cmd->target]; struct request *rq = NULL; idescsi_pc_t *pc = NULL; #if IDESCSI_DEBUG_LOG printk ("idescsi_queue called, serial = %lu, cmd[0] = %x, id = %d\n", cmd->serial_number, cmd->cmnd[0], cmd->target); #endif /* IDESCSI_DEBUG_LOG */ if (!drive) { printk (KERN_ERR "ide-scsi: drive id %d not present\n", cmd->target); goto abort; } pc = kmalloc (sizeof (idescsi_pc_t), GFP_ATOMIC); rq = kmalloc (sizeof (struct request), GFP_ATOMIC); if (rq == NULL || pc == NULL) { printk (KERN_ERR "ide-scsi: %s: out of memory\n", drive->name); goto abort; } memset (pc->c, 0, 12); pc->flags = 0; pc->rq = rq; memcpy (pc->c, cmd->cmnd, cmd->cmd_len); if (cmd->use_sg) { pc->buffer = NULL; pc->sg = cmd->request_buffer; } else { pc->buffer = cmd->request_buffer; pc->sg = NULL; } pc->b_count = 0; pc->request_transfer = pc->buffer_size = cmd->request_bufflen; pc->scsi_cmd = cmd; pc->done = done; idescsi_transform_pc1 (drive, pc); ide_init_drive_cmd (rq); rq->buffer = (char *) pc; rq->bh = idescsi_dma_bh (drive, pc); rq->cmd = IDESCSI_PC_RQ; (void) ide_do_drive_cmd (drive, rq, ide_end); return 0; abort: if (pc) kfree (pc); if (rq) kfree (rq); cmd->result = DID_ERROR << 16; done(cmd); return 0; } int idescsi_abort (Scsi_Cmnd *cmd) { return SCSI_ABORT_SNOOZE; } int idescsi_reset (Scsi_Cmnd *cmd, unsigned int resetflags) { return SCSI_RESET_PUNT; } #ifdef MODULE Scsi_Host_Template idescsi_template = IDESCSI; int init_module (void) { idescsi_init (); idescsi_template.module = &__this_module; scsi_register_module (MODULE_SCSI_HA, &idescsi_template); return 0; } void cleanup_module (void) { ide_drive_t *drive; byte media[] = {TYPE_DISK, TYPE_TAPE, TYPE_PROCESSOR, TYPE_WORM, TYPE_ROM, TYPE_SCANNER, TYPE_MOD, 255}; int i, failed; scsi_unregister_module (MODULE_SCSI_HA, &idescsi_template); for (i = 0; media[i] != 255; i++) { failed = 0; while ((drive = ide_scan_devices (media[i], &idescsi_driver, failed)) != NULL) if (idescsi_cleanup (drive)) { printk ("%s: cleanup_module() called while still busy\n", drive->name); failed++; } } ide_unregister_module(&idescsi_module); } #endif /* MODULE */