diff options
Diffstat (limited to 'linux/src/drivers/scsi/sd.c')
| -rw-r--r-- | linux/src/drivers/scsi/sd.c | 1635 |
1 files changed, 1635 insertions, 0 deletions
diff --git a/linux/src/drivers/scsi/sd.c b/linux/src/drivers/scsi/sd.c new file mode 100644 index 0000000..c647ab4 --- /dev/null +++ b/linux/src/drivers/scsi/sd.c @@ -0,0 +1,1635 @@ +/* + * 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: + */ |