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-rw-r--r--linux/src/drivers/scsi/sd.c1635
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:
+ */