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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [drivers/] [scsi/] [sd.c] - Rev 1765
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/* * sd.c Copyright (C) 1992 Drew Eckhardt * Copyright (C) 1993, 1994, 1995 Eric Youngdale * * Linux scsi disk driver * Initial versions: Drew Eckhardt * Subsequent revisions: Eric Youngdale * * <drew@colorado.edu> * * Modified by Eric Youngdale ericy@cais.com to * add scatter-gather, multiple outstanding request, and other * enhancements. * * Modified by Eric Youngdale eric@aib.com to support loadable * low-level scsi drivers. */ #include <linux/module.h> #ifdef MODULE /* * This is a variable in scsi.c that is set when we are processing something * after boot time. By definition, this is true when we are a loadable module * ourselves. */ #define MODULE_FLAG 1 #else #define MODULE_FLAG scsi_loadable_module_flag #endif /* MODULE */ #include <linux/fs.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/mm.h> #include <linux/string.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <asm/system.h> #define MAJOR_NR SCSI_DISK_MAJOR #include <linux/blk.h> #include "scsi.h" #include "hosts.h" #include "sd.h" #include <scsi/scsi_ioctl.h> #include "constants.h" #include <linux/genhd.h> /* * static const char RCSid[] = "$Header:"; */ #define MAX_RETRIES 5 /* * Time out in seconds for disks and Magneto-opticals (which are slower). */ #define SD_TIMEOUT (20 * HZ) #define SD_MOD_TIMEOUT (25 * HZ) #define CLUSTERABLE_DEVICE(SC) (SC->host->use_clustering && \ SC->device->type != TYPE_MOD) struct hd_struct * sd; Scsi_Disk * rscsi_disks = NULL; static int * sd_sizes; static int * sd_blocksizes; static int * sd_hardsizes; /* Hardware sector size */ extern int sd_ioctl(struct inode *, struct file *, unsigned int, unsigned long); static int check_scsidisk_media_change(kdev_t); static int fop_revalidate_scsidisk(kdev_t); static int sd_init_onedisk(int); static void requeue_sd_request (Scsi_Cmnd * SCpnt); static int sd_init(void); static void sd_finish(void); static int sd_attach(Scsi_Device *); static int sd_detect(Scsi_Device *); static void sd_detach(Scsi_Device *); struct Scsi_Device_Template sd_template = { NULL, "disk", "sd", NULL, TYPE_DISK, SCSI_DISK_MAJOR, 0, 0, 0, 1, sd_detect, sd_init, sd_finish, sd_attach, sd_detach }; static int sd_open(struct inode * inode, struct file * filp) { int target; target = DEVICE_NR(inode->i_rdev); if(target >= sd_template.dev_max || !rscsi_disks[target].device) return -ENXIO; /* No such device */ /* * Make sure that only one process can do a check_change_disk at one time. * This is also used to lock out further access when the partition table * is being re-read. */ while (rscsi_disks[target].device->busy) barrier(); if(rscsi_disks[target].device->removable) { check_disk_change(inode->i_rdev); /* * If the drive is empty, just let the open fail. */ if ( !rscsi_disks[target].ready ) return -ENXIO; /* * Similarly, if the device has the write protect tab set, * have the open fail if the user expects to be able to write * to the thing. */ if ( (rscsi_disks[target].write_prot) && (filp->f_mode & 2) ) return -EROFS; } /* * See if we are requesting a non-existent partition. Do this * after checking for disk change. */ if(sd_sizes[MINOR(inode->i_rdev)] == 0) return -ENXIO; if(rscsi_disks[target].device->removable) if(!rscsi_disks[target].device->access_count) sd_ioctl(inode, NULL, SCSI_IOCTL_DOORLOCK, 0); rscsi_disks[target].device->access_count++; if (rscsi_disks[target].device->host->hostt->usage_count) (*rscsi_disks[target].device->host->hostt->usage_count)++; if(sd_template.usage_count) (*sd_template.usage_count)++; return 0; } static void sd_release(struct inode * inode, struct file * file) { int target; fsync_dev(inode->i_rdev); target = DEVICE_NR(inode->i_rdev); rscsi_disks[target].device->access_count--; if (rscsi_disks[target].device->host->hostt->usage_count) (*rscsi_disks[target].device->host->hostt->usage_count)--; if(sd_template.usage_count) (*sd_template.usage_count)--; if(rscsi_disks[target].device->removable) { if(!rscsi_disks[target].device->access_count) sd_ioctl(inode, NULL, SCSI_IOCTL_DOORUNLOCK, 0); } } static void sd_geninit(struct gendisk *); static struct file_operations sd_fops = { NULL, /* lseek - default */ block_read, /* read - general block-dev read */ block_write, /* write - general block-dev write */ NULL, /* readdir - bad */ NULL, /* select */ sd_ioctl, /* ioctl */ NULL, /* mmap */ sd_open, /* open code */ sd_release, /* release */ block_fsync, /* fsync */ NULL, /* fasync */ check_scsidisk_media_change, /* Disk change */ fop_revalidate_scsidisk /* revalidate */ }; static struct gendisk sd_gendisk = { MAJOR_NR, /* Major number */ "sd", /* Major name */ 4, /* Bits to shift to get real from partition */ 1 << 4, /* Number of partitions per real */ 0, /* maximum number of real */ sd_geninit, /* init function */ NULL, /* hd struct */ NULL, /* block sizes */ 0, /* number */ NULL, /* internal */ NULL /* next */ }; static void sd_geninit (struct gendisk *ignored) { int i; for (i = 0; i < sd_template.dev_max; ++i) if(rscsi_disks[i].device) sd[i << 4].nr_sects = rscsi_disks[i].capacity; #if 0 /* No longer needed - we keep track of this as we attach/detach */ sd_gendisk.nr_real = sd_template.dev_max; #endif } /* * rw_intr is the interrupt routine for the device driver. * It will be notified on the end of a SCSI read / write, and * will take one of several actions based on success or failure. */ static void rw_intr (Scsi_Cmnd *SCpnt) { int result = SCpnt->result; int this_count = SCpnt->bufflen >> 9; int good_sectors = (result == 0 ? this_count : 0); int block_sectors = 1; #ifdef DEBUG printk("sd%c : rw_intr(%d, %d)\n", 'a' + MINOR(SCpnt->request.rq_dev), SCpnt->host->host_no, result); #endif /* Handle MEDIUM ERRORs that indicate partial success. Since this is a relatively rare error condition, no care is taken to avoid unnecessary additional work such as memcpy's that could be avoided. */ if (driver_byte(result) != 0 && /* An error occurred */ SCpnt->sense_buffer[0] == 0xF0 && /* Sense data is valid */ SCpnt->sense_buffer[2] == MEDIUM_ERROR) { long error_sector = (SCpnt->sense_buffer[3] << 24) | (SCpnt->sense_buffer[4] << 16) | (SCpnt->sense_buffer[5] << 8) | SCpnt->sense_buffer[6]; int sector_size = rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].sector_size; if (SCpnt->request.bh != NULL) block_sectors = SCpnt->request.bh->b_size >> 9; if (sector_size == 1024) { error_sector <<= 1; if (block_sectors < 2) block_sectors = 2; } else if (sector_size == 256) error_sector >>= 1; error_sector -= sd[MINOR(SCpnt->request.rq_dev)].start_sect; error_sector &= ~ (block_sectors - 1); good_sectors = error_sector - SCpnt->request.sector; if (good_sectors < 0 || good_sectors >= this_count) good_sectors = 0; } /* * Handle RECOVERED ERRORs that indicate success after recovery action * by the target device. */ if (SCpnt->sense_buffer[0] == 0xF0 && /* Sense data is valid */ SCpnt->sense_buffer[2] == RECOVERED_ERROR) { printk("scsidisk recovered I/O error: dev %s, sector %lu, absolute sector %lu\n", kdevname(SCpnt->request.rq_dev), SCpnt->request.sector, SCpnt->request.sector + sd[MINOR(SCpnt->request.rq_dev)].start_sect); good_sectors = this_count; result = 0; } /* * First case : we assume that the command succeeded. One of two things * will happen here. Either we will be finished, or there will be more * sectors that we were unable to read last time. */ if (good_sectors > 0) { #ifdef DEBUG printk("sd%c : %d sectors remain.\n", 'a' + MINOR(SCpnt->request.rq_dev), SCpnt->request.nr_sectors); printk("use_sg is %d\n ",SCpnt->use_sg); #endif if (SCpnt->use_sg) { struct scatterlist * sgpnt; int i; sgpnt = (struct scatterlist *) SCpnt->buffer; for(i=0; i<SCpnt->use_sg; i++) { #ifdef DEBUG printk(":%x %x %d\n",sgpnt[i].alt_address, sgpnt[i].address, sgpnt[i].length); #endif if (sgpnt[i].alt_address) { if (SCpnt->request.cmd == READ) memcpy(sgpnt[i].alt_address, sgpnt[i].address, sgpnt[i].length); scsi_free(sgpnt[i].address, sgpnt[i].length); } } /* Free list of scatter-gather pointers */ scsi_free(SCpnt->buffer, SCpnt->sglist_len); } else { if (SCpnt->buffer != SCpnt->request.buffer) { #ifdef DEBUG printk("nosg: %x %x %d\n",SCpnt->request.buffer, SCpnt->buffer, SCpnt->bufflen); #endif if (SCpnt->request.cmd == READ) memcpy(SCpnt->request.buffer, SCpnt->buffer, SCpnt->bufflen); scsi_free(SCpnt->buffer, SCpnt->bufflen); } } /* * If multiple sectors are requested in one buffer, then * they will have been finished off by the first command. * If not, then we have a multi-buffer command. */ if (SCpnt->request.nr_sectors > this_count) { SCpnt->request.errors = 0; if (!SCpnt->request.bh) { #ifdef DEBUG printk("sd%c : handling page request, no buffer\n", 'a' + MINOR(SCpnt->request.rq_dev)); #endif /* * The SCpnt->request.nr_sectors field is always done in * 512 byte sectors, even if this really isn't the case. */ panic("sd.c: linked page request (%lx %x)", SCpnt->request.sector, this_count); } } SCpnt = end_scsi_request(SCpnt, 1, good_sectors); if (result == 0) { requeue_sd_request(SCpnt); return; } } if (good_sectors == 0) { /* Free up any indirection buffers we allocated for DMA purposes. */ if (SCpnt->use_sg) { struct scatterlist * sgpnt; int i; sgpnt = (struct scatterlist *) SCpnt->buffer; for(i=0; i<SCpnt->use_sg; i++) { #ifdef DEBUG printk("err: %x %x %d\n",SCpnt->request.buffer, SCpnt->buffer, SCpnt->bufflen); #endif if (sgpnt[i].alt_address) { scsi_free(sgpnt[i].address, sgpnt[i].length); } } scsi_free(SCpnt->buffer, SCpnt->sglist_len); /* Free list of scatter-gather pointers */ } else { #ifdef DEBUG printk("nosgerr: %x %x %d\n",SCpnt->request.buffer, SCpnt->buffer, SCpnt->bufflen); #endif if (SCpnt->buffer != SCpnt->request.buffer) scsi_free(SCpnt->buffer, SCpnt->bufflen); } } /* * Now, if we were good little boys and girls, Santa left us a request * sense buffer. We can extract information from this, so we * can choose a block to remap, etc. */ if (driver_byte(result) != 0) { if (suggestion(result) == SUGGEST_REMAP) { #ifdef REMAP /* * Not yet implemented. A read will fail after being remapped, * a write will call the strategy routine again. */ if rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].remap { result = 0; } else #endif } if ((SCpnt->sense_buffer[0] & 0x7f) == 0x70) { if ((SCpnt->sense_buffer[2] & 0xf) == UNIT_ATTENTION) { if(rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].device->removable) { /* detected disc change. set a bit and quietly refuse * further access. */ rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].device->changed = 1; SCpnt = end_scsi_request(SCpnt, 0, this_count); requeue_sd_request(SCpnt); return; } else { /* * Must have been a power glitch, or a bus reset. * Could not have been a media change, so we just retry * the request and see what happens. */ requeue_sd_request(SCpnt); return; } } } /* If we had an ILLEGAL REQUEST returned, then we may have * performed an unsupported command. The only thing this should be * would be a ten byte read where only a six byte read was supported. * Also, on a system where READ CAPACITY failed, we have read past * the end of the disk. */ if (SCpnt->sense_buffer[2] == ILLEGAL_REQUEST) { if (rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].ten) { rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].ten = 0; requeue_sd_request(SCpnt); result = 0; } else { /* ???? */ } } if (SCpnt->sense_buffer[2] == MEDIUM_ERROR) { printk("scsi%d: MEDIUM ERROR on channel %d, id %d, lun %d, CDB: ", SCpnt->host->host_no, (int) SCpnt->channel, (int) SCpnt->target, (int) SCpnt->lun); print_command(SCpnt->cmnd); print_sense("sd", SCpnt); SCpnt = end_scsi_request(SCpnt, 0, block_sectors); requeue_sd_request(SCpnt); return; } } /* driver byte != 0 */ if (result) { printk("SCSI disk error : host %d channel %d id %d lun %d return code = %x\n", rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].device->host->host_no, rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].device->channel, rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].device->id, rscsi_disks[DEVICE_NR(SCpnt->request.rq_dev)].device->lun, result); if (driver_byte(result) & DRIVER_SENSE) print_sense("sd", SCpnt); SCpnt = end_scsi_request(SCpnt, 0, SCpnt->request.current_nr_sectors); requeue_sd_request(SCpnt); return; } } /* * requeue_sd_request() is the request handler function for the sd driver. * Its function in life is to take block device requests, and translate * them to SCSI commands. */ static void do_sd_request (void) { Scsi_Cmnd * SCpnt = NULL; Scsi_Device * SDev; struct request * req = NULL; unsigned long flags; int flag = 0; save_flags(flags); while (1==1){ cli(); if (CURRENT != NULL && CURRENT->rq_status == RQ_INACTIVE) { restore_flags(flags); return; } INIT_SCSI_REQUEST; SDev = rscsi_disks[DEVICE_NR(CURRENT->rq_dev)].device; /* * I am not sure where the best place to do this is. We need * to hook in a place where we are likely to come if in user * space. */ if( SDev->was_reset ) { /* * We need to relock the door, but we might * be in an interrupt handler. Only do this * from user space, since we do not want to * sleep from an interrupt. */ if( SDev->removable && !intr_count ) { scsi_ioctl(SDev, SCSI_IOCTL_DOORLOCK, 0); /* scsi_ioctl may allow CURRENT to change, so start over. */ SDev->was_reset = 0; continue; } SDev->was_reset = 0; } /* We have to be careful here. allocate_device will get a free pointer, * but there is no guarantee that it is queueable. In normal usage, * we want to call this, because other types of devices may have the * host all tied up, and we want to make sure that we have at least * one request pending for this type of device. We can also come * through here while servicing an interrupt, because of the need to * start another command. If we call allocate_device more than once, * then the system can wedge if the command is not queueable. The * request_queueable function is safe because it checks to make sure * that the host is able to take another command before it returns * a pointer. */ if (flag++ == 0) SCpnt = allocate_device(&CURRENT, rscsi_disks[DEVICE_NR(CURRENT->rq_dev)].device, 0); else SCpnt = NULL; /* * The following restore_flags leads to latency problems. FIXME. * Using a "sti()" gets rid of the latency problems but causes * race conditions and crashes. */ restore_flags(flags); /* This is a performance enhancement. We dig down into the request * list and try to find a queueable request (i.e. device not busy, * and host able to accept another command. If we find one, then we * queue it. This can make a big difference on systems with more than * one disk drive. We want to have the interrupts off when monkeying * with the request list, because otherwise the kernel might try to * slip in a request in between somewhere. */ if (!SCpnt && sd_template.nr_dev > 1){ struct request *req1; req1 = NULL; cli(); req = CURRENT; while(req){ SCpnt = request_queueable(req, rscsi_disks[DEVICE_NR(req->rq_dev)].device); if(SCpnt) break; req1 = req; req = req->next; } if (SCpnt && req->rq_status == RQ_INACTIVE) { if (req == CURRENT) CURRENT = CURRENT->next; else req1->next = req->next; } restore_flags(flags); } if (!SCpnt) return; /* Could not find anything to do */ /* Queue command */ requeue_sd_request(SCpnt); } /* While */ } static void requeue_sd_request (Scsi_Cmnd * SCpnt) { int dev, devm, block, this_count; unsigned char cmd[10]; int bounce_size, contiguous; int max_sg; struct buffer_head * bh, *bhp; char * buff, *bounce_buffer; repeat: if(!SCpnt || SCpnt->request.rq_status == RQ_INACTIVE) { do_sd_request(); return; } devm = MINOR(SCpnt->request.rq_dev); dev = DEVICE_NR(SCpnt->request.rq_dev); block = SCpnt->request.sector; this_count = 0; #ifdef DEBUG printk("Doing sd request, dev = %d, block = %d\n", devm, block); #endif if (devm >= (sd_template.dev_max << 4) || !rscsi_disks[dev].device || block + SCpnt->request.nr_sectors > sd[devm].nr_sects) { SCpnt = end_scsi_request(SCpnt, 0, SCpnt->request.nr_sectors); goto repeat; } block += sd[devm].start_sect; if (rscsi_disks[dev].device->changed) { /* * quietly refuse to do anything to a changed disc until the changed * bit has been reset */ /* printk("SCSI disk has been changed. Prohibiting further I/O.\n"); */ SCpnt = end_scsi_request(SCpnt, 0, SCpnt->request.nr_sectors); goto repeat; } #ifdef DEBUG printk("sd%c : real dev = /dev/sd%c, block = %d\n", 'a' + devm, dev, block); #endif /* * If we have a 1K hardware sectorsize, prevent access to single * 512 byte sectors. In theory we could handle this - in fact * the scsi cdrom driver must be able to handle this because * we typically use 1K blocksizes, and cdroms typically have * 2K hardware sectorsizes. Of course, things are simpler * with the cdrom, since it is read-only. For performance * reasons, the filesystems should be able to handle this * and not force the scsi disk driver to use bounce buffers * for this. */ if (rscsi_disks[dev].sector_size == 1024) if((block & 1) || (SCpnt->request.nr_sectors & 1)) { printk("sd.c:Bad block number requested"); SCpnt = end_scsi_request(SCpnt, 0, SCpnt->request.nr_sectors); goto repeat; } switch (SCpnt->request.cmd) { case WRITE : if (!rscsi_disks[dev].device->writeable) { SCpnt = end_scsi_request(SCpnt, 0, SCpnt->request.nr_sectors); goto repeat; } cmd[0] = WRITE_6; break; case READ : cmd[0] = READ_6; break; default : panic ("Unknown sd command %d\n", SCpnt->request.cmd); } SCpnt->this_count = 0; /* If the host adapter can deal with very large scatter-gather * requests, it is a waste of time to cluster */ contiguous = (!CLUSTERABLE_DEVICE(SCpnt) ? 0 :1); bounce_buffer = NULL; bounce_size = (SCpnt->request.nr_sectors << 9); /* First see if we need a bounce buffer for this request. If we do, make * sure that we can allocate a buffer. Do not waste space by allocating * a bounce buffer if we are straddling the 16Mb line */ if (contiguous && SCpnt->request.bh && ((long) SCpnt->request.bh->b_data) + (SCpnt->request.nr_sectors << 9) - 1 > ISA_DMA_THRESHOLD && SCpnt->host->unchecked_isa_dma) { if(((long) SCpnt->request.bh->b_data) > ISA_DMA_THRESHOLD) bounce_buffer = (char *) scsi_malloc(bounce_size); if(!bounce_buffer) contiguous = 0; } if(contiguous && SCpnt->request.bh && SCpnt->request.bh->b_reqnext) for(bh = SCpnt->request.bh, bhp = bh->b_reqnext; bhp; bh = bhp, bhp = bhp->b_reqnext) { if(!CONTIGUOUS_BUFFERS(bh,bhp)) { if(bounce_buffer) scsi_free(bounce_buffer, bounce_size); contiguous = 0; break; } } if (!SCpnt->request.bh || contiguous) { /* case of page request (i.e. raw device), or unlinked buffer */ this_count = SCpnt->request.nr_sectors; buff = SCpnt->request.buffer; SCpnt->use_sg = 0; } else if (SCpnt->host->sg_tablesize == 0 || (need_isa_buffer && dma_free_sectors <= 10)) { /* Case of host adapter that cannot scatter-gather. We also * come here if we are running low on DMA buffer memory. We set * a threshold higher than that we would need for this request so * we leave room for other requests. Even though we would not need * it all, we need to be conservative, because if we run low enough * we have no choice but to panic. */ if (SCpnt->host->sg_tablesize != 0 && need_isa_buffer && dma_free_sectors <= 10) printk("Warning: SCSI DMA buffer space running low. Using non scatter-gather I/O.\n"); this_count = SCpnt->request.current_nr_sectors; buff = SCpnt->request.buffer; SCpnt->use_sg = 0; } else { /* Scatter-gather capable host adapter */ struct scatterlist * sgpnt; int count, this_count_max; int counted; bh = SCpnt->request.bh; this_count = 0; this_count_max = (rscsi_disks[dev].ten ? 0xffff : 0xff); count = 0; bhp = NULL; while(bh) { if ((this_count + (bh->b_size >> 9)) > this_count_max) break; if(!bhp || !CONTIGUOUS_BUFFERS(bhp,bh) || !CLUSTERABLE_DEVICE(SCpnt) || (SCpnt->host->unchecked_isa_dma && ((unsigned long) bh->b_data-1) == ISA_DMA_THRESHOLD)) { if (count < SCpnt->host->sg_tablesize) count++; else break; } this_count += (bh->b_size >> 9); bhp = bh; bh = bh->b_reqnext; } #if 0 if(SCpnt->host->unchecked_isa_dma && ((unsigned int) SCpnt->request.bh->b_data-1) == ISA_DMA_THRESHOLD) count--; #endif SCpnt->use_sg = count; /* Number of chains */ /* scsi_malloc can only allocate in chunks of 512 bytes */ count = (SCpnt->use_sg * sizeof(struct scatterlist) + 511) & ~511; SCpnt->sglist_len = count; max_sg = count / sizeof(struct scatterlist); if(SCpnt->host->sg_tablesize < max_sg) max_sg = SCpnt->host->sg_tablesize; sgpnt = (struct scatterlist * ) scsi_malloc(count); if (!sgpnt) { printk("Warning - running *really* short on DMA buffers\n"); SCpnt->use_sg = 0; /* No memory left - bail out */ this_count = SCpnt->request.current_nr_sectors; buff = SCpnt->request.buffer; } else { memset(sgpnt, 0, count); /* Zero so it is easy to fill, but only * if memory is available */ buff = (char *) sgpnt; counted = 0; for(count = 0, bh = SCpnt->request.bh, bhp = bh->b_reqnext; count < SCpnt->use_sg && bh; count++, bh = bhp) { bhp = bh->b_reqnext; if(!sgpnt[count].address) sgpnt[count].address = bh->b_data; sgpnt[count].length += bh->b_size; counted += bh->b_size >> 9; if (((long) sgpnt[count].address) + sgpnt[count].length - 1 > ISA_DMA_THRESHOLD && (SCpnt->host->unchecked_isa_dma) && !sgpnt[count].alt_address) { sgpnt[count].alt_address = sgpnt[count].address; /* We try to avoid exhausting the DMA pool, since it is * easier to control usage here. In other places we might * have a more pressing need, and we would be screwed if * we ran out */ if(dma_free_sectors < (sgpnt[count].length >> 9) + 10) { sgpnt[count].address = NULL; } else { sgpnt[count].address = (char *) scsi_malloc(sgpnt[count].length); } /* If we start running low on DMA buffers, we abort the * scatter-gather operation, and free all of the memory * we have allocated. We want to ensure that all scsi * operations are able to do at least a non-scatter/gather * operation */ if(sgpnt[count].address == NULL){ /* Out of dma memory */ #if 0 printk("Warning: Running low on SCSI DMA buffers"); /* Try switching back to a non s-g operation. */ while(--count >= 0){ if(sgpnt[count].alt_address) scsi_free(sgpnt[count].address, sgpnt[count].length); } this_count = SCpnt->request.current_nr_sectors; buff = SCpnt->request.buffer; SCpnt->use_sg = 0; scsi_free(sgpnt, SCpnt->sglist_len); #endif SCpnt->use_sg = count; this_count = counted -= bh->b_size >> 9; break; } } /* Only cluster buffers if we know that we can supply DMA * buffers large enough to satisfy the request. Do not cluster * a new request if this would mean that we suddenly need to * start using DMA bounce buffers */ if(bhp && CONTIGUOUS_BUFFERS(bh,bhp) && CLUSTERABLE_DEVICE(SCpnt)) { char * tmp; if (((long) sgpnt[count].address) + sgpnt[count].length + bhp->b_size - 1 > ISA_DMA_THRESHOLD && (SCpnt->host->unchecked_isa_dma) && !sgpnt[count].alt_address) continue; if(!sgpnt[count].alt_address) {count--; continue; } if(dma_free_sectors > 10) tmp = (char *) scsi_malloc(sgpnt[count].length + bhp->b_size); else { tmp = NULL; max_sg = SCpnt->use_sg; } if(tmp){ scsi_free(sgpnt[count].address, sgpnt[count].length); sgpnt[count].address = tmp; count--; continue; } /* If we are allowed another sg chain, then increment * counter so we can insert it. Otherwise we will end up truncating */ if (SCpnt->use_sg < max_sg) SCpnt->use_sg++; } /* contiguous buffers */ } /* for loop */ /* This is actually how many we are going to transfer */ this_count = counted; if(count < SCpnt->use_sg || SCpnt->use_sg > SCpnt->host->sg_tablesize){ bh = SCpnt->request.bh; printk("Use sg, count %d %x %d\n", SCpnt->use_sg, count, dma_free_sectors); printk("maxsg = %x, counted = %d this_count = %d\n", max_sg, counted, this_count); while(bh){ printk("[%p %lx] ", bh->b_data, bh->b_size); bh = bh->b_reqnext; } if(SCpnt->use_sg < 16) for(count=0; count<SCpnt->use_sg; count++) printk("{%d:%p %p %d} ", count, sgpnt[count].address, sgpnt[count].alt_address, sgpnt[count].length); panic("Ooops"); } if (SCpnt->request.cmd == WRITE) for(count=0; count<SCpnt->use_sg; count++) if(sgpnt[count].alt_address) memcpy(sgpnt[count].address, sgpnt[count].alt_address, sgpnt[count].length); } /* Able to malloc sgpnt */ } /* Host adapter capable of scatter-gather */ /* Now handle the possibility of DMA to addresses > 16Mb */ if(SCpnt->use_sg == 0){ if (((long) buff) + (this_count << 9) - 1 > ISA_DMA_THRESHOLD && (SCpnt->host->unchecked_isa_dma)) { if(bounce_buffer) buff = bounce_buffer; else buff = (char *) scsi_malloc(this_count << 9); if(buff == NULL) { /* Try backing off a bit if we are low on mem*/ this_count = SCpnt->request.current_nr_sectors; buff = (char *) scsi_malloc(this_count << 9); if(!buff) panic("Ran out of DMA buffers."); } if (SCpnt->request.cmd == WRITE) memcpy(buff, (char *)SCpnt->request.buffer, this_count << 9); } } #ifdef DEBUG printk("sd%c : %s %d/%d 512 byte blocks.\n", 'a' + devm, (SCpnt->request.cmd == WRITE) ? "writing" : "reading", this_count, SCpnt->request.nr_sectors); #endif cmd[1] = (SCpnt->lun << 5) & 0xe0; if (rscsi_disks[dev].sector_size == 1024){ if(block & 1) panic("sd.c:Bad block number requested"); if(this_count & 1) panic("sd.c:Bad block number requested"); block = block >> 1; this_count = this_count >> 1; } if (rscsi_disks[dev].sector_size == 256){ block = block << 1; this_count = this_count << 1; } if (((this_count > 0xff) || (block > 0x1fffff)) && rscsi_disks[dev].ten) { if (this_count > 0xffff) this_count = 0xffff; cmd[0] += READ_10 - READ_6 ; cmd[2] = (unsigned char) (block >> 24) & 0xff; cmd[3] = (unsigned char) (block >> 16) & 0xff; cmd[4] = (unsigned char) (block >> 8) & 0xff; cmd[5] = (unsigned char) block & 0xff; cmd[6] = cmd[9] = 0; cmd[7] = (unsigned char) (this_count >> 8) & 0xff; cmd[8] = (unsigned char) this_count & 0xff; } else { if (this_count > 0xff) this_count = 0xff; cmd[1] |= (unsigned char) ((block >> 16) & 0x1f); cmd[2] = (unsigned char) ((block >> 8) & 0xff); cmd[3] = (unsigned char) block & 0xff; cmd[4] = (unsigned char) this_count; cmd[5] = 0; } /* * We shouldn't disconnect in the middle of a sector, so with a dumb * host adapter, it's safe to assume that we can at least transfer * this many bytes between each connect / disconnect. */ SCpnt->transfersize = rscsi_disks[dev].sector_size; SCpnt->underflow = this_count << 9; scsi_do_cmd (SCpnt, (void *) cmd, buff, this_count * rscsi_disks[dev].sector_size, rw_intr, (SCpnt->device->type == TYPE_DISK ? SD_TIMEOUT : SD_MOD_TIMEOUT), MAX_RETRIES); } static int check_scsidisk_media_change(kdev_t full_dev){ int retval; int target; struct inode inode; int flag = 0; target = DEVICE_NR(full_dev); if (target >= sd_template.dev_max || !rscsi_disks[target].device) { printk("SCSI disk request error: invalid device.\n"); return 0; } if(!rscsi_disks[target].device->removable) return 0; inode.i_rdev = full_dev; /* This is all we really need here */ /* Using Start/Stop enables differentiation between drive with * no cartridge loaded - NOT READY, drive with changed cartridge - * UNIT ATTENTION, or with same cartridge - GOOD STATUS. * This also handles drives that auto spin down. eg iomega jaz 1GB * as this will spin up the drive. */ retval = sd_ioctl(&inode, NULL, SCSI_IOCTL_START_UNIT, 0); if(retval){ /* Unable to test, unit probably not ready. This usually * means there is no disc in the drive. Mark as changed, * and we will figure it out later once the drive is * available again. */ rscsi_disks[target].ready = 0; rscsi_disks[target].device->changed = 1; return 1; /* This will force a flush, if called from * check_disk_change */ } /* * for removable scsi disk ( FLOPTICAL ) we have to recognise the * presence of disk in the drive. This is kept in the Scsi_Disk * struct and tested at open ! Daniel Roche ( dan@lectra.fr ) */ rscsi_disks[target].ready = 1; /* FLOPTICAL */ retval = rscsi_disks[target].device->changed; if(!flag) rscsi_disks[target].device->changed = 0; return retval; } static void sd_init_done (Scsi_Cmnd * SCpnt) { struct request * req; req = &SCpnt->request; req->rq_status = RQ_SCSI_DONE; /* Busy, but indicate request done */ if (req->sem != NULL) { up(req->sem); } } static int sd_init_onedisk(int i) { unsigned char cmd[10]; unsigned char *buffer; unsigned long spintime; int the_result, retries; Scsi_Cmnd * SCpnt; /* We need to retry the READ_CAPACITY because a UNIT_ATTENTION is * considered a fatal error, and many devices report such an error * just after a scsi bus reset. */ SCpnt = allocate_device(NULL, rscsi_disks[i].device, 1); buffer = (unsigned char *) scsi_malloc(512); spintime = 0; /* Spin up drives, as required. Only do this at boot time */ /* Spinup needs to be done for module loads too. */ do{ retries = 0; while(retries < 3) { cmd[0] = TEST_UNIT_READY; cmd[1] = (rscsi_disks[i].device->lun << 5) & 0xe0; memset ((void *) &cmd[2], 0, 8); SCpnt->cmd_len = 0; SCpnt->sense_buffer[0] = 0; SCpnt->sense_buffer[2] = 0; { struct semaphore sem = MUTEX_LOCKED; /* Mark as really busy again */ SCpnt->request.rq_status = RQ_SCSI_BUSY; SCpnt->request.sem = &sem; scsi_do_cmd (SCpnt, (void *) cmd, (void *) buffer, 512, sd_init_done, SD_TIMEOUT, MAX_RETRIES); down(&sem); } the_result = SCpnt->result; retries++; if( the_result == 0 || SCpnt->sense_buffer[2] != UNIT_ATTENTION) break; } /* Look for non-removable devices that return NOT_READY. * Issue command to spin up drive for these cases. */ if(the_result && !rscsi_disks[i].device->removable && SCpnt->sense_buffer[2] == NOT_READY) { unsigned long time1; if(!spintime){ printk( "sd%c: Spinning up disk...", 'a' + i ); cmd[0] = START_STOP; cmd[1] = (rscsi_disks[i].device->lun << 5) & 0xe0; cmd[1] |= 1; /* Return immediately */ memset ((void *) &cmd[2], 0, 8); cmd[4] = 1; /* Start spin cycle */ SCpnt->cmd_len = 0; SCpnt->sense_buffer[0] = 0; SCpnt->sense_buffer[2] = 0; { struct semaphore sem = MUTEX_LOCKED; /* Mark as really busy again */ SCpnt->request.rq_status = RQ_SCSI_BUSY; SCpnt->request.sem = &sem; scsi_do_cmd (SCpnt, (void *) cmd, (void *) buffer, 512, sd_init_done, SD_TIMEOUT, MAX_RETRIES); down(&sem); } spintime = jiffies; } time1 = jiffies + HZ; while(jiffies < time1); /* Wait 1 second for next try */ printk( "." ); } } while(the_result && spintime && spintime+100*HZ > jiffies); if (spintime) { if (the_result) printk( "not responding...\n" ); else printk( "ready\n" ); } retries = 3; do { cmd[0] = READ_CAPACITY; cmd[1] = (rscsi_disks[i].device->lun << 5) & 0xe0; memset ((void *) &cmd[2], 0, 8); memset ((void *) buffer, 0, 8); SCpnt->cmd_len = 0; SCpnt->sense_buffer[0] = 0; SCpnt->sense_buffer[2] = 0; { struct semaphore sem = MUTEX_LOCKED; /* Mark as really busy again */ SCpnt->request.rq_status = RQ_SCSI_BUSY; SCpnt->request.sem = &sem; scsi_do_cmd (SCpnt, (void *) cmd, (void *) buffer, 8, sd_init_done, SD_TIMEOUT, MAX_RETRIES); down(&sem); /* sleep until it is ready */ } the_result = SCpnt->result; retries--; } while(the_result && retries); SCpnt->request.rq_status = RQ_INACTIVE; /* Mark as not busy */ wake_up(&SCpnt->device->device_wait); /* Wake up a process waiting for device */ /* * The SCSI standard says: * "READ CAPACITY is necessary for self configuring software" * While not mandatory, support of READ CAPACITY is strongly encouraged. * We used to die if we couldn't successfully do a READ CAPACITY. * But, now we go on about our way. The side effects of this are * * 1. We can't know block size with certainty. I have said "512 bytes * is it" as this is most common. * * 2. Recovery from when some one attempts to read past the end of the * raw device will be slower. */ if (the_result) { printk ("sd%c : READ CAPACITY failed.\n" "sd%c : status = %x, message = %02x, host = %d, driver = %02x \n", 'a' + i, 'a' + i, status_byte(the_result), msg_byte(the_result), host_byte(the_result), driver_byte(the_result) ); if (driver_byte(the_result) & DRIVER_SENSE) printk("sd%c : extended sense code = %1x \n", 'a' + i, SCpnt->sense_buffer[2] & 0xf); else printk("sd%c : sense not available. \n", 'a' + i); printk("sd%c : block size assumed to be 512 bytes, disk size 1GB. \n", 'a' + i); rscsi_disks[i].capacity = 0x1fffff; rscsi_disks[i].sector_size = 512; /* Set dirty bit for removable devices if not ready - sometimes drives * will not report this properly. */ if(rscsi_disks[i].device->removable && SCpnt->sense_buffer[2] == NOT_READY) rscsi_disks[i].device->changed = 1; } else { /* * FLOPTICAL , if read_capa is ok , drive is assumed to be ready */ rscsi_disks[i].ready = 1; rscsi_disks[i].capacity = 1 + ((buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]); rscsi_disks[i].sector_size = (buffer[4] << 24) | (buffer[5] << 16) | (buffer[6] << 8) | buffer[7]; if (rscsi_disks[i].sector_size == 0) { rscsi_disks[i].sector_size = 512; printk("sd%c : sector size 0 reported, assuming 512.\n", 'a' + i); } if (rscsi_disks[i].sector_size != 512 && rscsi_disks[i].sector_size != 1024 && rscsi_disks[i].sector_size != 256) { printk ("sd%c : unsupported sector size %d.\n", 'a' + i, rscsi_disks[i].sector_size); if(rscsi_disks[i].device->removable){ rscsi_disks[i].capacity = 0; } else { printk ("scsi : deleting disk entry.\n"); rscsi_disks[i].device = NULL; sd_template.nr_dev--; sd_gendisk.nr_real--; return i; } } { /* * The msdos fs needs to know the hardware sector size * So I have created this table. See ll_rw_blk.c * Jacques Gelinas (Jacques@solucorp.qc.ca) */ int m, mb; int sz_quot, sz_rem; int hard_sector = rscsi_disks[i].sector_size; /* There are 16 minors allocated for each major device */ for (m=i<<4; m<((i+1)<<4); m++){ sd_hardsizes[m] = hard_sector; } mb = rscsi_disks[i].capacity / 1024 * hard_sector / 1024; /* sz = div(m/100, 10); this seems to not be in the libr */ m = (mb + 50) / 100; sz_quot = m / 10; sz_rem = m - (10 * sz_quot); printk ("SCSI device sd%c: hdwr sector= %d bytes." " Sectors= %d [%d MB] [%d.%1d GB]\n", i+'a', hard_sector, rscsi_disks[i].capacity, mb, sz_quot, sz_rem); } if(rscsi_disks[i].sector_size == 1024) rscsi_disks[i].capacity <<= 1; /* Change into 512 byte sectors */ if(rscsi_disks[i].sector_size == 256) rscsi_disks[i].capacity >>= 1; /* Change into 512 byte sectors */ } /* * Unless otherwise specified, this is not write protected. */ rscsi_disks[i].write_prot = 0; if ( rscsi_disks[i].device->removable && rscsi_disks[i].ready ) { /* FLOPTICAL */ /* * for removable scsi disk ( FLOPTICAL ) we have to recognise * the Write Protect Flag. This flag is kept in the Scsi_Disk struct * and tested at open ! * Daniel Roche ( dan@lectra.fr ) */ memset ((void *) &cmd[0], 0, 8); cmd[0] = MODE_SENSE; cmd[1] = (rscsi_disks[i].device->lun << 5) & 0xe0; cmd[2] = 1; /* page code 1 ?? */ cmd[4] = 12; SCpnt->cmd_len = 0; SCpnt->sense_buffer[0] = 0; SCpnt->sense_buffer[2] = 0; /* same code as READCAPA !! */ { struct semaphore sem = MUTEX_LOCKED; SCpnt->request.rq_status = RQ_SCSI_BUSY; /* Mark as really busy again */ SCpnt->request.sem = &sem; scsi_do_cmd (SCpnt, (void *) cmd, (void *) buffer, 512, sd_init_done, SD_TIMEOUT, MAX_RETRIES); down(&sem); } the_result = SCpnt->result; SCpnt->request.rq_status = RQ_INACTIVE; /* Mark as not busy */ wake_up(&SCpnt->device->device_wait); if ( the_result ) { printk ("sd%c: test WP failed, assume Write Protected\n",i+'a'); rscsi_disks[i].write_prot = 1; } else { rscsi_disks[i].write_prot = ((buffer[2] & 0x80) != 0); printk ("sd%c: Write Protect is %s\n",i+'a', rscsi_disks[i].write_prot ? "on" : "off"); } } /* check for write protect */ rscsi_disks[i].ten = 1; rscsi_disks[i].remap = 1; scsi_free(buffer, 512); return i; } /* * The sd_init() function looks at all SCSI drives present, determines * their size, and reads partition table entries for them. */ static int sd_registered = 0; static int sd_init() { int i; if (sd_template.dev_noticed == 0) return 0; if(!sd_registered) { if (register_blkdev(MAJOR_NR,"sd",&sd_fops)) { printk("Unable to get major %d for SCSI disk\n",MAJOR_NR); return 1; } sd_registered++; } /* We do not support attaching loadable devices yet. */ if(rscsi_disks) return 0; sd_template.dev_max = sd_template.dev_noticed + SD_EXTRA_DEVS; rscsi_disks = (Scsi_Disk *) scsi_init_malloc(sd_template.dev_max * sizeof(Scsi_Disk), GFP_ATOMIC); memset(rscsi_disks, 0, sd_template.dev_max * sizeof(Scsi_Disk)); sd_sizes = (int *) scsi_init_malloc((sd_template.dev_max << 4) * sizeof(int), GFP_ATOMIC); memset(sd_sizes, 0, (sd_template.dev_max << 4) * sizeof(int)); sd_blocksizes = (int *) scsi_init_malloc((sd_template.dev_max << 4) * sizeof(int), GFP_ATOMIC); sd_hardsizes = (int *) scsi_init_malloc((sd_template.dev_max << 4) * sizeof(int), GFP_ATOMIC); for(i=0;i<(sd_template.dev_max << 4);i++){ sd_blocksizes[i] = 1024; sd_hardsizes[i] = 512; } blksize_size[MAJOR_NR] = sd_blocksizes; hardsect_size[MAJOR_NR] = sd_hardsizes; sd = (struct hd_struct *) scsi_init_malloc((sd_template.dev_max << 4) * sizeof(struct hd_struct), GFP_ATOMIC); sd_gendisk.max_nr = sd_template.dev_max; sd_gendisk.part = sd; sd_gendisk.sizes = sd_sizes; sd_gendisk.real_devices = (void *) rscsi_disks; return 0; } static void sd_finish(void) { struct gendisk *gendisk; int i; blk_dev[MAJOR_NR].request_fn = DEVICE_REQUEST; for (gendisk = gendisk_head; gendisk != NULL; gendisk = gendisk->next) if (gendisk == &sd_gendisk) break; if (gendisk == NULL) { sd_gendisk.next = gendisk_head; gendisk_head = &sd_gendisk; } for (i = 0; i < sd_template.dev_max; ++i) if (!rscsi_disks[i].capacity && rscsi_disks[i].device) { if (MODULE_FLAG && !rscsi_disks[i].has_part_table) { sd_sizes[i << 4] = rscsi_disks[i].capacity; /* revalidate does sd_init_onedisk via MAYBE_REINIT*/ revalidate_scsidisk(MKDEV(MAJOR_NR, i << 4), 0); } else i=sd_init_onedisk(i); rscsi_disks[i].has_part_table = 1; } /* If our host adapter is capable of scatter-gather, then we increase * the read-ahead to 16 blocks (32 sectors). If not, we use * a two block (4 sector) read ahead. */ if(rscsi_disks[0].device && rscsi_disks[0].device->host->sg_tablesize) read_ahead[MAJOR_NR] = 120; /* 120 sector read-ahead */ else read_ahead[MAJOR_NR] = 4; /* 4 sector read-ahead */ return; } static int sd_detect(Scsi_Device * SDp){ if(SDp->type != TYPE_DISK && SDp->type != TYPE_MOD) return 0; printk("Detected scsi %sdisk sd%c at scsi%d, channel %d, id %d, lun %d\n", SDp->removable ? "removable " : "", 'a'+ (sd_template.dev_noticed++), SDp->host->host_no, SDp->channel, SDp->id, SDp->lun); return 1; } static int sd_attach(Scsi_Device * SDp){ Scsi_Disk * dpnt; int i; if(SDp->type != TYPE_DISK && SDp->type != TYPE_MOD) return 0; if(sd_template.nr_dev >= sd_template.dev_max) { SDp->attached--; return 1; } for(dpnt = rscsi_disks, i=0; i<sd_template.dev_max; i++, dpnt++) if(!dpnt->device) break; if(i >= sd_template.dev_max) panic ("scsi_devices corrupt (sd)"); SDp->scsi_request_fn = do_sd_request; rscsi_disks[i].device = SDp; rscsi_disks[i].has_part_table = 0; sd_template.nr_dev++; sd_gendisk.nr_real++; return 0; } #define DEVICE_BUSY rscsi_disks[target].device->busy #define USAGE rscsi_disks[target].device->access_count #define CAPACITY rscsi_disks[target].capacity #define MAYBE_REINIT sd_init_onedisk(target) #define GENDISK_STRUCT sd_gendisk /* This routine is called to flush all partitions and partition tables * for a changed scsi disk, and then re-read the new partition table. * If we are revalidating a disk because of a media change, then we * enter with usage == 0. If we are using an ioctl, we automatically have * usage == 1 (we need an open channel to use an ioctl :-), so this * is our limit. */ int revalidate_scsidisk(kdev_t dev, int maxusage){ int target; struct gendisk * gdev; unsigned long flags; int max_p; int start; int i; target = DEVICE_NR(dev); gdev = &GENDISK_STRUCT; save_flags(flags); cli(); if (DEVICE_BUSY || USAGE > maxusage) { restore_flags(flags); printk("Device busy for revalidation (usage=%d)\n", USAGE); return -EBUSY; } DEVICE_BUSY = 1; restore_flags(flags); max_p = gdev->max_p; start = target << gdev->minor_shift; for (i=max_p - 1; i >=0 ; i--) { int minor = start+i; kdev_t devi = MKDEV(MAJOR_NR, minor); sync_dev(devi); invalidate_inodes(devi); invalidate_buffers(devi); gdev->part[minor].start_sect = 0; gdev->part[minor].nr_sects = 0; /* * Reset the blocksize for everything so that we can read * the partition table. */ blksize_size[MAJOR_NR][minor] = 1024; } #ifdef MAYBE_REINIT MAYBE_REINIT; #endif gdev->part[start].nr_sects = CAPACITY; resetup_one_dev(gdev, target); DEVICE_BUSY = 0; return 0; } static int fop_revalidate_scsidisk(kdev_t dev){ return revalidate_scsidisk(dev, 0); } static void sd_detach(Scsi_Device * SDp) { Scsi_Disk * dpnt; int i; int max_p; int start; for(dpnt = rscsi_disks, i=0; i<sd_template.dev_max; i++, dpnt++) if(dpnt->device == SDp) { /* If we are disconnecting a disk driver, sync and invalidate * everything */ max_p = sd_gendisk.max_p; start = i << sd_gendisk.minor_shift; for (i=max_p - 1; i >=0 ; i--) { int minor = start+i; kdev_t devi = MKDEV(MAJOR_NR, minor); sync_dev(devi); invalidate_inodes(devi); invalidate_buffers(devi); sd_gendisk.part[minor].start_sect = 0; sd_gendisk.part[minor].nr_sects = 0; sd_sizes[minor] = 0; } dpnt->has_part_table = 0; dpnt->device = NULL; dpnt->capacity = 0; SDp->attached--; sd_template.dev_noticed--; sd_template.nr_dev--; sd_gendisk.nr_real--; return; } return; } #ifdef MODULE int init_module(void) { sd_template.usage_count = &mod_use_count_; return scsi_register_module(MODULE_SCSI_DEV, &sd_template); } void cleanup_module( void) { struct gendisk * prev_sdgd; struct gendisk * sdgd; scsi_unregister_module(MODULE_SCSI_DEV, &sd_template); unregister_blkdev(SCSI_DISK_MAJOR, "sd"); sd_registered--; if( rscsi_disks != NULL ) { scsi_init_free((char *) rscsi_disks, (sd_template.dev_noticed + SD_EXTRA_DEVS) * sizeof(Scsi_Disk)); scsi_init_free((char *) sd_sizes, sd_template.dev_max * sizeof(int)); scsi_init_free((char *) sd_blocksizes, sd_template.dev_max * sizeof(int)); scsi_init_free((char *) sd_hardsizes, sd_template.dev_max * sizeof(int)); scsi_init_free((char *) sd, (sd_template.dev_max << 4) * sizeof(struct hd_struct)); /* * Now remove sd_gendisk from the linked list */ sdgd = gendisk_head; prev_sdgd = NULL; while(sdgd != &sd_gendisk) { prev_sdgd = sdgd; sdgd = sdgd->next; } if(sdgd != &sd_gendisk) printk("sd_gendisk not in disk chain.\n"); else { if(prev_sdgd != NULL) prev_sdgd->next = sdgd->next; else gendisk_head = sdgd->next; } } blksize_size[MAJOR_NR] = NULL; blk_dev[MAJOR_NR].request_fn = NULL; blk_size[MAJOR_NR] = NULL; hardsect_size[MAJOR_NR] = NULL; read_ahead[MAJOR_NR] = 0; sd_template.dev_max = 0; } #endif /* MODULE */ /* * Overrides for Emacs so that we almost 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: nil * tab-width: 8 * End: */