/*
* sd.c Copyright (C) 1992 Drew Eckhardt
* Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
*
* Linux scsi disk driver
* Initial versions: Drew Eckhardt
* Subsequent revisions: Eric Youngdale
* Modification history:
* - Drew Eckhardt <drew@colorado.edu> original
* - Eric Youngdale <eric@andante.org> add scatter-gather, multiple
* outstanding request, and other enhancements.
* Support loadable low-level scsi drivers.
* - Jirka Hanika <geo@ff.cuni.cz> support more scsi disks using
* eight major numbers.
* - Richard Gooch <rgooch@atnf.csiro.au> support devfs.
* - Torben Mathiasen <tmm@image.dk> Resource allocation fixes in
* sd_init and cleanups.
* - Alex Davis <letmein@erols.com> Fix problem where partition info
* not being read in sd_open. Fix problem where removable media
* could be ejected after sd_open.
* - Douglas Gilbert <dgilbert@interlog.com> cleanup for lk 2.5 series
*
* Logging policy (needs CONFIG_SCSI_LOGGING defined):
* - setting up transfer: SCSI_LOG_HLQUEUE levels 1 and 2
* - end of transfer (bh + scsi_lib): SCSI_LOG_HLCOMPLETE level 1
* - entering sd_ioctl: SCSI_LOG_IOCTL level 1
* - entering other commands: SCSI_LOG_HLQUEUE level 3
* Note: when the logging level is set by the user, it must be greater
* than the level indicated above to trigger output.
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/bio.h>
#include <linux/string.h>
#include <linux/hdreg.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <linux/smp.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#define MAJOR_NR SCSI_DISK0_MAJOR
#define LOCAL_END_REQUEST
#define DEVICE_NR(device) (((major(device) & SD_MAJOR_MASK) << (8 - 4)) + (minor(device) >> 4))
#include <linux/blk.h>
#include <linux/blkpg.h>
#include "scsi.h"
#include "hosts.h"
#include "sd.h"
#include <scsi/scsi_ioctl.h>
#include <scsi/scsicam.h> /* must follow "hosts.h" */
#include <linux/genhd.h>
/* static char sd_version_str[] = "Version: 2.0.3 (20020417)"; */
#define SD_MAJOR(i) (!(i) ? SCSI_DISK0_MAJOR : SCSI_DISK1_MAJOR-1+(i))
#define SCSI_DISKS_PER_MAJOR 16
#define SD_MAJOR_NUMBER(i) SD_MAJOR((i) >> 8)
#define SD_MINOR_NUMBER(i) ((i) & 255)
#define MKDEV_SD_PARTITION(i) mk_kdev(SD_MAJOR_NUMBER(i), (i) & 255)
#define MKDEV_SD(index) MKDEV_SD_PARTITION((index) << 4)
#define N_USED_SD_MAJORS (1 + ((sd_template.dev_max - 1) >> 4))
#define MAX_RETRIES 5
/*
* Time out in seconds for disks and Magneto-opticals (which are slower).
*/
#define SD_TIMEOUT (30 * HZ)
#define SD_MOD_TIMEOUT (75 * HZ)
#define SD_DSK_ARR_LUMP 6 /* amount to over allocate sd_dsk_arr by */
struct hd_struct *sd;
static Scsi_Disk ** sd_dsk_arr;
static rwlock_t sd_dsk_arr_lock = RW_LOCK_UNLOCKED;
static int check_scsidisk_media_change(kdev_t);
static int sd_revalidate(kdev_t);
static void sd_init_onedisk(Scsi_Disk * sdkp, int dsk_nr);
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 *);
static int sd_init_command(Scsi_Cmnd *);
static struct Scsi_Device_Template sd_template = {
module:THIS_MODULE,
name:"disk",
tag:"sd",
scsi_type:TYPE_DISK,
major:SCSI_DISK0_MAJOR,
/*
* Secondary range of majors that this driver handles.
*/
min_major:SCSI_DISK1_MAJOR,
max_major:SCSI_DISK7_MAJOR,
blk:1,
detect:sd_detect,
init:sd_init,
finish:sd_finish,
attach:sd_attach,
detach:sd_detach,
init_command:sd_init_command,
};
static void sd_rw_intr(Scsi_Cmnd * SCpnt);
static Scsi_Disk * sd_get_sdisk(int index);
#if defined(CONFIG_PPC32)
/**
* sd_find_target - find kdev_t of first scsi disk that matches
* given host and scsi_id.
* @host: Scsi_Host object pointer that owns scsi device of interest
* @scsi_id: scsi (target) id number of device of interest
*
* Returns kdev_t of first scsi device that matches arguments or
* NODEV of no match.
*
* Notes: Looks like a hack, should scan for <host,channel,id,lin>
* tuple.
* [Architectural dependency: ppc only.] Moved here from
* arch/ppc/pmac_setup.c.
**/
kdev_t __init
sd_find_target(void *hp, int scsi_id)
{
Scsi_Disk *sdkp;
Scsi_Device *sdp;
struct Scsi_Host *shp = hp;
int dsk_nr;
kdev_t retval = NODEV;
unsigned long iflags;
SCSI_LOG_HLQUEUE(3, printk("sd_find_target: host_nr=%d, "
"scsi_id=%d\n", shp->host_no, scsi_id));
read_lock_irqsave(&sd_dsk_arr_lock, iflags);
for (dsk_nr = 0; dsk_nr < sd_template.dev_max; ++dsk_nr) {
sdkp = sd_dsk_arr[dsk_nr];
if (sdkp == NULL)
continue;
sdp = sdkp->device;
if (sdp && (sdp->host == shp) && (sdp->id == scsi_id)) {
retval = MKDEV_SD(dsk_nr);
break;
}
}
read_unlock_irqrestore(&sd_dsk_arr_lock, iflags);
return retval;
}
#endif
/**
* sd_ioctl - process an ioctl
* @inode: only i_rdev member may be used
* @filp: only f_mode and f_flags may be used
* @cmd: ioctl command number
* @arg: this is third argument given to ioctl(2) system call.
* Often contains a pointer.
*
* Returns 0 if successful (some ioctls return postive numbers on
* success as well). Returns a negated errno value in case of error.
*
* Note: most ioctls are forward onto the block subsystem or further
* down in the scsi subsytem.
**/
static int sd_ioctl(struct inode * inode, struct file * filp,
unsigned int cmd, unsigned long arg)
{
kdev_t dev = inode->i_rdev;
Scsi_Disk * sdkp;
struct Scsi_Host * host;
Scsi_Device * sdp;
int diskinfo[4];
int dsk_nr = DEVICE_NR(dev);
SCSI_LOG_IOCTL(1, printk("sd_ioctl: dsk_nr=%d, cmd=0x%x\n",
dsk_nr, cmd));
sdkp = sd_get_sdisk(dsk_nr);
if ((NULL == sdkp) || (NULL == (sdp = sdkp->device)))
return -ENODEV;
/*
* If we are in the middle of error recovery, don't let anyone
* else try and use this device. Also, if error recovery fails, it
* may try and take the device offline, in which case all further
* access to the device is prohibited.
*/
if( !scsi_block_when_processing_errors(sdp) )
return -ENODEV;
switch (cmd)
{
case HDIO_GETGEO: /* Return BIOS disk parameters */
{
struct hd_geometry *loc = (struct hd_geometry *) arg;
if(!loc)
return -EINVAL;
host = sdp->host;
/* default to most commonly used values */
diskinfo[0] = 0x40; /* 1 << 6 */
diskinfo[1] = 0x20; /* 1 << 5 */
diskinfo[2] = sdkp->capacity >> 11;
/* override with calculated, extended default,
or driver values */
if(host->hostt->bios_param != NULL)
host->hostt->bios_param(sdkp, inode->i_bdev,
&diskinfo[0]);
else
scsicam_bios_param(sdkp, inode->i_bdev, &diskinfo[0]);
if (put_user(diskinfo[0], &loc->heads) ||
put_user(diskinfo[1], &loc->sectors) ||
put_user(diskinfo[2], &loc->cylinders) ||
put_user((unsigned)
get_start_sect(inode->i_bdev),
(unsigned long *) &loc->start))
return -EFAULT;
return 0;
}
default:
return scsi_ioctl(sdp, cmd, (void *) arg);
}
}
static void sd_dskname(unsigned int dsk_nr, char *buffer)
{
if (dsk_nr < 26)
sprintf(buffer, "sd%c", 'a' + dsk_nr);
else {
unsigned int min1;
unsigned int min2;
/*
* For larger numbers of disks, we need to go to a new
* naming scheme.
*/
min1 = dsk_nr / 26;
min2 = dsk_nr % 26;
sprintf(buffer, "sd%c%c", 'a' + min1 - 1, 'a' + min2);
}
}
/**
* sd_find_queue - yields queue associated with device
* @dev: kernel device descriptor (kdev_t)
*
* Returns NULL if no match, otherwise returns pointer to associated
* request queue.
*
* Note: this function is invoked (often) from the block subsystem
* and should not wait on anything (sd_get_sdisk() does have a read
* spinlock).
**/
static request_queue_t *sd_find_queue(kdev_t dev)
{
Scsi_Disk *sdkp;
int dsk_nr = DEVICE_NR(dev);
sdkp = sd_get_sdisk(dsk_nr);
if (sdkp && sdkp->device)
return &sdkp->device->request_queue;
else
return NULL; /* No such device */
}
static struct gendisk **sd_disks;
/**
* sd_init_command - build a scsi (read or write) command from
* information in the request structure.
* @SCpnt: pointer to mid-level's per scsi command structure that
* contains request and into which the scsi command is written
*
* Returns 1 if successful and 0 if error (or cannot be done now).
**/
static int sd_init_command(Scsi_Cmnd * SCpnt)
{
int dsk_nr, part_nr, block, this_count;
Scsi_Device *sdp;
#if CONFIG_SCSI_LOGGING
char nbuff[6];
#endif
/*
* don't support specials for nwo
*/
if (!(SCpnt->request->flags & REQ_CMD))
return 0;
part_nr = SD_PARTITION(SCpnt->request->rq_dev);
dsk_nr = DEVICE_NR(SCpnt->request->rq_dev);
block = SCpnt->request->sector;
this_count = SCpnt->request_bufflen >> 9;
SCSI_LOG_HLQUEUE(1, printk("sd_command_init: dsk_nr=%d, block=%d, "
"count=%d\n", dsk_nr, block, this_count));
sdp = SCpnt->device;
/* >>>>> the "(part_nr & 0xf)" excludes 15th partition, why?? */
/* >>>>> this change is not in the lk 2.5 series */
if (part_nr >= (sd_template.dev_max << 4) || (part_nr & 0xf) ||
!sdp || !sdp->online ||
block + SCpnt->request->nr_sectors > get_capacity(sd_disks[dsk_nr])) {
SCSI_LOG_HLQUEUE(2, printk("Finishing %ld sectors\n",
SCpnt->request->nr_sectors));
SCSI_LOG_HLQUEUE(2, printk("Retry with 0x%p\n", SCpnt));
return 0;
}
if (sdp->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"); */
return 0;
}
SCSI_LOG_HLQUEUE(2, sd_dskname(dsk_nr, nbuff));
SCSI_LOG_HLQUEUE(2, printk("%s : [part_nr=%d], block=%d\n",
nbuff, part_nr, block));
/*
* 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 (sdp->sector_size == 1024) {
if ((block & 1) || (SCpnt->request->nr_sectors & 1)) {
printk(KERN_ERR "sd: Bad block number requested");
return 0;
} else {
block = block >> 1;
this_count = this_count >> 1;
}
}
if (sdp->sector_size == 2048) {
if ((block & 3) || (SCpnt->request->nr_sectors & 3)) {
printk(KERN_ERR "sd: Bad block number requested");
return 0;
} else {
block = block >> 2;
this_count = this_count >> 2;
}
}
if (sdp->sector_size == 4096) {
if ((block & 7) || (SCpnt->request->nr_sectors & 7)) {
printk(KERN_ERR "sd: Bad block number requested");
return 0;
} else {
block = block >> 3;
this_count = this_count >> 3;
}
}
if (rq_data_dir(SCpnt->request) == WRITE) {
if (!sdp->writeable) {
return 0;
}
SCpnt->cmnd[0] = WRITE_6;
SCpnt->sc_data_direction = SCSI_DATA_WRITE;
} else if (rq_data_dir(SCpnt->request) == READ) {
SCpnt->cmnd[0] = READ_6;
SCpnt->sc_data_direction = SCSI_DATA_READ;
} else {
printk(KERN_ERR "sd: Unknown command %lx\n",
SCpnt->request->flags);
/* overkill panic("Unknown sd command %lx\n", SCpnt->request->flags); */
return 0;
}
SCSI_LOG_HLQUEUE(2, printk("%s : %s %d/%ld 512 byte blocks.\n",
nbuff, (rq_data_dir(SCpnt->request) == WRITE) ?
"writing" : "reading", this_count, SCpnt->request->nr_sectors));
SCpnt->cmnd[1] = (SCpnt->device->scsi_level <= SCSI_2) ?
((SCpnt->lun << 5) & 0xe0) : 0;
if (((this_count > 0xff) || (block > 0x1fffff)) || SCpnt->device->ten) {
if (this_count > 0xffff)
this_count = 0xffff;
SCpnt->cmnd[0] += READ_10 - READ_6;
SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
SCpnt->cmnd[5] = (unsigned char) block & 0xff;
SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
} else {
if (this_count > 0xff)
this_count = 0xff;
SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
SCpnt->cmnd[3] = (unsigned char) block & 0xff;
SCpnt->cmnd[4] = (unsigned char) this_count;
SCpnt->cmnd[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 = sdp->sector_size;
SCpnt->underflow = this_count << 9;
SCpnt->allowed = MAX_RETRIES;
SCpnt->timeout_per_command = (SCpnt->device->type == TYPE_DISK ?
SD_TIMEOUT : SD_MOD_TIMEOUT);
/*
* This is the completion routine we use. This is matched in terms
* of capability to this function.
*/
SCpnt->done = sd_rw_intr;
/*
* This indicates that the command is ready from our end to be
* queued.
*/
return 1;
}
/**
* sd_open - open a scsi disk device
* @inode: only i_rdev member may be used
* @filp: only f_mode and f_flags may be used
*
* Returns 0 if successful. Returns a negated errno value in case
* of error.
*
* Note: This can be called from a user context (e.g. fsck(1) )
* or from within the kernel (e.g. as a result of a mount(1) ).
* In the latter case @inode and @filp carry an abridged amount
* of information as noted above.
**/
static int sd_open(struct inode *inode, struct file *filp)
{
int retval = -ENXIO;
Scsi_Device * sdp;
Scsi_Disk * sdkp;
int dsk_nr = DEVICE_NR(inode->i_rdev);
SCSI_LOG_HLQUEUE(3, printk("sd_open: dsk_nr=%d, part_nr=%d\n",
dsk_nr, SD_PARTITION(inode->i_rdev)));
sdkp = sd_get_sdisk(dsk_nr);
if ((NULL == sdkp) || (NULL == (sdp = sdkp->device)))
return -ENXIO; /* No such device */
/*
* If the device is in error recovery, wait until it is done.
* If the device is offline, then disallow any access to it.
*/
if (!scsi_block_when_processing_errors(sdp))
return -ENXIO;
/*
* The following code can sleep.
* Module unloading must be prevented
*/
if (sdp->host->hostt->module)
__MOD_INC_USE_COUNT(sdp->host->hostt->module);
if (sd_template.module)
__MOD_INC_USE_COUNT(sd_template.module);
sdp->access_count++;
if (sdp->removable) {
check_disk_change(inode->i_bdev);
/*
* If the drive is empty, just let the open fail.
*/
if ((!sdkp->media_present) && !(filp->f_flags & O_NDELAY)) {
retval = -ENOMEDIUM;
goto error_out;
}
/*
* 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 ((sdkp->write_prot) && (filp->f_mode & FMODE_WRITE)) {
retval = -EROFS;
goto error_out;
}
}
/*
* It is possible that the disk changing stuff resulted in the device
* being taken offline. If this is the case, report this to the user,
* and don't pretend that the open actually succeeded.
*/
if (!sdp->online) {
goto error_out;
}
if (sdp->removable)
if (sdp->access_count==1)
if (scsi_block_when_processing_errors(sdp))
scsi_ioctl(sdp, SCSI_IOCTL_DOORLOCK, NULL);
return 0;
error_out:
sdp->access_count--;
if (sdp->host->hostt->module)
__MOD_DEC_USE_COUNT(sdp->host->hostt->module);
if (sd_template.module)
__MOD_DEC_USE_COUNT(sd_template.module);
return retval;
}
/**
* sd_release - invoked when the (last) close(2) is called on this
* scsi disk.
* @inode: only i_rdev member may be used
* @filp: only f_mode and f_flags may be used
*
* Returns 0.
*
* Note: may block (uninterruptible) if error recovery is underway
* on this disk.
**/
static int sd_release(struct inode *inode, struct file *filp)
{
Scsi_Disk * sdkp;
int dsk_nr = DEVICE_NR(inode->i_rdev);
Scsi_Device * sdp;
SCSI_LOG_HLQUEUE(3, printk("sd_release: dsk_nr=%d, part_nr=%d\n",
dsk_nr, SD_PARTITION(inode->i_rdev)));
sdkp = sd_get_sdisk(dsk_nr);
if ((NULL == sdkp) || (NULL == (sdp = sdkp->device)))
return -ENODEV; /* open uses ENXIO ?? */
/* ... and what if there are packets in flight and this close()
* is followed by a "rmmod sd_mod" */
sdp->access_count--;
if (sdp->removable) {
if (!sdp->access_count)
if (scsi_block_when_processing_errors(sdp))
scsi_ioctl(sdp, SCSI_IOCTL_DOORUNLOCK, NULL);
}
if (sdp->host->hostt->module)
__MOD_DEC_USE_COUNT(sdp->host->hostt->module);
if (sd_template.module)
__MOD_DEC_USE_COUNT(sd_template.module);
return 0;
}
static struct block_device_operations sd_fops =
{
owner: THIS_MODULE,
open: sd_open,
release: sd_release,
ioctl: sd_ioctl,
check_media_change: check_scsidisk_media_change,
revalidate: sd_revalidate
};
/**
* sd_rw_intr - bottom half handler: called when the lower level
* driver has completed (successfully or otherwise) a scsi command.
* @SCpnt: mid-level's per command structure.
*
* Note: potentially run from within an ISR. Must not block.
**/
static void sd_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;
long error_sector;
#if CONFIG_SCSI_LOGGING
char nbuff[6];
SCSI_LOG_HLCOMPLETE(1, sd_dskname(DEVICE_NR(SCpnt->request->rq_dev),
nbuff));
SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: %s: res=0x%x\n",
nbuff, result));
if (0 != result) {
SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: sb[0,2,asc,ascq]"
"=%x,%x,%x,%x\n", SCpnt->sense_buffer[0],
SCpnt->sense_buffer[2], SCpnt->sense_buffer[12],
SCpnt->sense_buffer[13]));
}
#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.
*/
/* An error occurred */
if (driver_byte(result) != 0 && /* An error occured */
SCpnt->sense_buffer[0] != 0xF0) { /* Sense data is valid */
switch (SCpnt->sense_buffer[2]) {
case MEDIUM_ERROR:
error_sector = (SCpnt->sense_buffer[3] << 24) |
(SCpnt->sense_buffer[4] << 16) |
(SCpnt->sense_buffer[5] << 8) |
SCpnt->sense_buffer[6];
if (SCpnt->request->bio != NULL)
block_sectors = bio_sectors(SCpnt->request->bio);
switch (SCpnt->device->sector_size) {
case 1024:
error_sector <<= 1;
if (block_sectors < 2)
block_sectors = 2;
break;
case 2048:
error_sector <<= 2;
if (block_sectors < 4)
block_sectors = 4;
break;
case 4096:
error_sector <<=3;
if (block_sectors < 8)
block_sectors = 8;
break;
case 256:
error_sector >>= 1;
break;
default:
break;
}
error_sector &= ~(block_sectors - 1);
good_sectors = error_sector - SCpnt->request->sector;
if (good_sectors < 0 || good_sectors >= this_count)
good_sectors = 0;
break;
case RECOVERED_ERROR:
/*
* An error occured, but it recovered. Inform the
* user, but make sure that it's not treated as a
* hard error.
*/
print_sense("sd", SCpnt);
result = 0;
SCpnt->sense_buffer[0] = 0x0;
good_sectors = this_count;
break;
case ILLEGAL_REQUEST:
if (SCpnt->device->ten == 1) {
if (SCpnt->cmnd[0] == READ_10 ||
SCpnt->cmnd[0] == WRITE_10)
SCpnt->device->ten = 0;
}
break;
default:
break;
}
}
/*
* This calls the generic completion function, now that we know
* how many actual sectors finished, and how many sectors we need
* to say have failed.
*/
scsi_io_completion(SCpnt, good_sectors, block_sectors);
}
static void
sd_set_media_not_present(Scsi_Disk *sdkp) {
sdkp->media_present = 0;
sdkp->capacity = 0;
sdkp->device->changed = 1;
}
/**
* check_scsidisk_media_change - self descriptive
* @full_dev: kernel device descriptor (kdev_t)
*
* Returns 0 if not applicable or no change; 1 if change
*
* Note: this function is invoked from the block subsystem.
**/
static int check_scsidisk_media_change(kdev_t full_dev)
{
int retval;
int flag = 0; /* <<<< what is this for?? */
Scsi_Disk * sdkp;
Scsi_Device * sdp;
int dsk_nr = DEVICE_NR(full_dev);
sdkp = sd_get_sdisk(dsk_nr);
SCSI_LOG_HLQUEUE(3, printk("check_scsidisk_media_change: "
"dsk_nr=%d\n", dsk_nr));
if ((NULL == sdkp) || (NULL == (sdp = sdkp->device))) {
printk(KERN_ERR "check_scsidisk_media_change: dsk_nr=%d, "
"invalid device\n", dsk_nr);
return 0;
}
if (!sdp->removable)
return 0;
/*
* If the device is offline, don't send any commands - just pretend as
* if the command failed. If the device ever comes back online, we
* can deal with it then. It is only because of unrecoverable errors
* that we would ever take a device offline in the first place.
*/
if (sdp->online == FALSE) {
sd_set_media_not_present(sdkp);
return 1; /* This will force a flush, if called from
* check_disk_change */
}
/* 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 = -ENODEV;
if (scsi_block_when_processing_errors(sdp))
retval = scsi_ioctl(sdp, SCSI_IOCTL_START_UNIT, NULL);
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. */
sd_set_media_not_present(sdkp);
return 1; /* This will force a flush, if called from
* check_disk_change */
}
/*
* For removable scsi disk we have to recognise the presence
* of a disk in the drive. This is kept in the Scsi_Disk
* struct and tested at open ! Daniel Roche ( dan@lectra.fr )
*/
sdkp->media_present = 1;
retval = sdp->changed;
if (!flag)
sdp->changed = 0;
return retval;
}
static int
sd_media_not_present(Scsi_Disk *sdkp, Scsi_Request *SRpnt) {
int the_result = SRpnt->sr_result;
if (the_result != 0
&& (driver_byte(the_result) & DRIVER_SENSE) != 0
&& (SRpnt->sr_sense_buffer[2] == NOT_READY ||
SRpnt->sr_sense_buffer[2] == UNIT_ATTENTION)
&& SRpnt->sr_sense_buffer[12] == 0x3A /* medium not present */) {
sd_set_media_not_present(sdkp);
return 1;
}
return 0;
}
/*
* spinup disk - called only in sd_init_onedisk()
*/
static void
sd_spinup_disk(Scsi_Disk *sdkp, char *diskname,
Scsi_Request *SRpnt, unsigned char *buffer) {
unsigned char cmd[10];
Scsi_Device *sdp = sdkp->device;
unsigned long spintime_value = 0;
int the_result, retries, spintime;
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] = (sdp->scsi_level <= SCSI_2) ?
((sdp->lun << 5) & 0xe0) : 0;
memset((void *) &cmd[2], 0, 8);
SRpnt->sr_cmd_len = 0;
SRpnt->sr_sense_buffer[0] = 0;
SRpnt->sr_sense_buffer[2] = 0;
SRpnt->sr_data_direction = SCSI_DATA_NONE;
scsi_wait_req (SRpnt, (void *) cmd, (void *) buffer,
0/*512*/, SD_TIMEOUT, MAX_RETRIES);
the_result = SRpnt->sr_result;
retries++;
if (the_result == 0
|| SRpnt->sr_sense_buffer[2] != UNIT_ATTENTION)
break;
}
/*
* If the drive has indicated to us that it doesn't have
* any media in it, don't bother with any of the rest of
* this crap.
*/
if (sd_media_not_present(sdkp, SRpnt))
return;
/* Look for non-removable devices that return NOT_READY.
* Issue command to spin up drive for these cases. */
if (the_result && !sdp->removable &&
SRpnt->sr_sense_buffer[2] == NOT_READY) {
unsigned long time1;
if (!spintime) {
printk(KERN_NOTICE "%s: Spinning up disk...",
diskname);
cmd[0] = START_STOP;
cmd[1] = (sdp->scsi_level <= SCSI_2) ?
((sdp->lun << 5) & 0xe0) : 0;
cmd[1] |= 1; /* Return immediately */
memset((void *) &cmd[2], 0, 8);
cmd[4] = 1; /* Start spin cycle */
SRpnt->sr_cmd_len = 0;
SRpnt->sr_sense_buffer[0] = 0;
SRpnt->sr_sense_buffer[2] = 0;
SRpnt->sr_data_direction = SCSI_DATA_READ;
scsi_wait_req(SRpnt, (void *)cmd,
(void *) buffer, 0/*512*/,
SD_TIMEOUT, MAX_RETRIES);
spintime_value = jiffies;
}
spintime = 1;
time1 = HZ;
/* Wait 1 second for next try */
do {
current->state = TASK_UNINTERRUPTIBLE;
time1 = schedule_timeout(time1);
} while(time1);
printk(".");
}
} while (the_result && spintime &&
time_after(spintime_value + 100 * HZ, jiffies));
if (spintime) {
if (the_result)
printk("not responding...\n");
else
printk("ready\n");
}
}
/*
* read disk capacity - called only in sd_init_onedisk()
*/
static void
sd_read_capacity(Scsi_Disk *sdkp, char *diskname,
Scsi_Request *SRpnt, unsigned char *buffer) {
unsigned char cmd[10];
Scsi_Device *sdp = sdkp->device;
int the_result, retries;
int sector_size;
retries = 3;
do {
cmd[0] = READ_CAPACITY;
cmd[1] = (sdp->scsi_level <= SCSI_2) ?
((sdp->lun << 5) & 0xe0) : 0;
memset((void *) &cmd[2], 0, 8);
memset((void *) buffer, 0, 8);
SRpnt->sr_cmd_len = 0;
SRpnt->sr_sense_buffer[0] = 0;
SRpnt->sr_sense_buffer[2] = 0;
SRpnt->sr_data_direction = SCSI_DATA_READ;
scsi_wait_req(SRpnt, (void *) cmd, (void *) buffer,
8, SD_TIMEOUT, MAX_RETRIES);
if (sd_media_not_present(sdkp, SRpnt))
return;
the_result = SRpnt->sr_result;
retries--;
} while (the_result && retries);
if (the_result) {
printk(KERN_NOTICE "%s : READ CAPACITY failed.\n"
"%s : status=%x, message=%02x, host=%d, driver=%02x \n",
diskname, diskname,
status_byte(the_result),
msg_byte(the_result),
host_byte(the_result),
driver_byte(the_result));
if (driver_byte(the_result) & DRIVER_SENSE)
print_req_sense("sd", SRpnt);
else
printk("%s : sense not available. \n", diskname);
/* Set dirty bit for removable devices if not ready -
* sometimes drives will not report this properly. */
if (sdp->removable &&
SRpnt->sr_sense_buffer[2] == NOT_READY)
sdp->changed = 1;
/* Either no media are present but the drive didnt tell us,
or they are present but the read capacity command fails */
/* sdkp->media_present = 0; -- not always correct */
sdkp->capacity = 0x200000; /* 1 GB - random */
return;
}
sdkp->capacity = 1 + ((buffer[0] << 24) |
(buffer[1] << 16) |
(buffer[2] << 8) |
buffer[3]);
sector_size = (buffer[4] << 24) |
(buffer[5] << 16) | (buffer[6] << 8) | buffer[7];
if (sector_size == 0) {
sector_size = 512;
printk(KERN_NOTICE "%s : sector size 0 reported, "
"assuming 512.\n", diskname);
}
if (sector_size != 512 &&
sector_size != 1024 &&
sector_size != 2048 &&
sector_size != 4096 &&
sector_size != 256) {
printk(KERN_NOTICE "%s : unsupported sector size "
"%d.\n", diskname, sector_size);
/*
* The user might want to re-format the drive with
* a supported sectorsize. Once this happens, it
* would be relatively trivial to set the thing up.
* For this reason, we leave the thing in the table.
*/
sdkp->capacity = 0;
}
{
/*
* 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 hard_sector = sector_size;
int sz = sdkp->capacity * (hard_sector/256);
request_queue_t *queue = &sdp->request_queue;
blk_queue_hardsect_size(queue, hard_sector);
printk(KERN_NOTICE "SCSI device %s: "
"%d %d-byte hdwr sectors (%d MB)\n",
diskname, sdkp->capacity,
hard_sector, (sz/2 - sz/1250 + 974)/1950);
}
/* Rescale capacity to 512-byte units */
if (sector_size == 4096)
sdkp->capacity <<= 3;
if (sector_size == 2048)
sdkp->capacity <<= 2;
if (sector_size == 1024)
sdkp->capacity <<= 1;
if (sector_size == 256)
sdkp->capacity >>= 1;
sdkp->device->sector_size = sector_size;
}
/*
* read write protect setting, if possible - called only in sd_init_onedisk()
*/
static void
sd_read_write_protect_flag(Scsi_Disk *sdkp, char *diskname,
Scsi_Request *SRpnt, unsigned char *buffer) {
Scsi_Device *sdp = sdkp->device;
unsigned char cmd[8];
int the_result;
/*
* For removable scsi disks 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 )
*
* Changed to get all pages (0x3f) rather than page 1 to
* get around devices which do not have a page 1. Since
* we're only interested in the header anyway, this should
* be fine.
* -- Matthew Dharm (mdharm-scsi@one-eyed-alien.net)
*
* As it turns out, some devices return an error for
* every MODE_SENSE request except one for page 0.
* So, we should also try that. --aeb
*/
memset((void *) &cmd[0], 0, 8);
cmd[0] = MODE_SENSE;
cmd[1] = (sdp->scsi_level <= SCSI_2) ?
((sdp->lun << 5) & 0xe0) : 0;
cmd[2] = 0x3f; /* Get all pages */
cmd[4] = 255; /* Ask for 255 bytes, even tho we want just the first 8 */
SRpnt->sr_cmd_len = 0;
SRpnt->sr_sense_buffer[0] = 0;
SRpnt->sr_sense_buffer[2] = 0;
SRpnt->sr_data_direction = SCSI_DATA_READ;
scsi_wait_req(SRpnt, (void *) cmd, (void *) buffer,
255, SD_TIMEOUT, MAX_RETRIES);
the_result = SRpnt->sr_result;
if (the_result) {
printk("%s: test WP failed, assume Write Enabled\n",
diskname);
/* alternatively, try page 0 */
} else {
sdkp->write_prot = ((buffer[2] & 0x80) != 0);
printk(KERN_NOTICE "%s: Write Protect is %s\n", diskname,
sdkp->write_prot ? "on" : "off");
}
}
/**
* sd_init_onedisk - called the first time a new disk is seen,
* performs disk spin up, read_capacity, etc.
* @sdkp: pointer to associated Scsi_Disk object
* @dsk_nr: disk number within this driver (e.g. 0->/dev/sda,
* 1->/dev/sdb, etc)
*
* Note: this function is local to this driver.
**/
static void
sd_init_onedisk(Scsi_Disk * sdkp, int dsk_nr) {
char diskname[40];
unsigned char *buffer;
Scsi_Device *sdp;
Scsi_Request *SRpnt;
SCSI_LOG_HLQUEUE(3, printk("sd_init_onedisk: dsk_nr=%d\n", dsk_nr));
/*
* Get the name of the disk, in case we need to log it somewhere.
*/
sd_dskname(dsk_nr, diskname);
/*
* If the device is offline, don't try and read capacity or any
* of the other niceties.
*/
sdp = sdkp->device;
if (sdp->online == FALSE)
return;
SRpnt = scsi_allocate_request(sdp);
if (!SRpnt) {
printk(KERN_WARNING "(sd_init_onedisk:) Request allocation "
"failure.\n");
return;
}
buffer = kmalloc(512, GFP_DMA);
if (!buffer) {
printk(KERN_WARNING "(sd_init_onedisk:) Memory allocation "
"failure.\n");
goto leave;
}
/* defaults, until the device tells us otherwise */
sdkp->capacity = 0;
sdkp->device->sector_size = 512;
sdkp->media_present = 1;
sdkp->write_prot = 0;
sd_spinup_disk(sdkp, diskname, SRpnt, buffer);
if (sdkp->media_present)
sd_read_capacity(sdkp, diskname, SRpnt, buffer);
if (sdp->removable && sdkp->media_present)
sd_read_write_protect_flag(sdkp, diskname, SRpnt, buffer);
SRpnt->sr_device->ten = 1;
SRpnt->sr_device->remap = 1;
leave:
scsi_release_request(SRpnt);
kfree(buffer);
}
/*
* The sd_init() function looks at all SCSI drives present, determines
* their size, and reads partition table entries for them.
*/
static int sd_registered;
/**
* sd_init- called during driver initialization (after
* sd_detect() is called for each scsi device present).
*
* Returns 0 is successful (or already called); 1 if error
*
* Note: this function is invoked from the scsi mid-level.
**/
static int sd_init()
{
int k, maxparts;
Scsi_Disk * sdkp;
SCSI_LOG_HLQUEUE(3, printk("sd_init: dev_noticed=%d\n",
sd_template.dev_noticed));
if (sd_template.dev_noticed == 0)
return 0;
if (NULL == sd_dsk_arr)
sd_template.dev_max = sd_template.dev_noticed + SD_EXTRA_DEVS;
if (sd_template.dev_max > N_SD_MAJORS * SCSI_DISKS_PER_MAJOR)
sd_template.dev_max = N_SD_MAJORS * SCSI_DISKS_PER_MAJOR;
/* At most 16 partitions on each scsi disk. */
maxparts = (sd_template.dev_max << 4);
if (maxparts == 0)
return 0;
if (!sd_registered) {
for (k = 0; k < N_USED_SD_MAJORS; k++) {
if (register_blkdev(SD_MAJOR(k), "sd", &sd_fops)) {
printk(KERN_NOTICE "Unable to get major %d "
"for SCSI disk\n", SD_MAJOR(k));
return 1;
}
}
sd_registered++;
}
/* We do not support attaching loadable devices yet. */
if (sd_dsk_arr)
return 0;
/* allocate memory */
#define init_mem_lth(x,n) x = vmalloc((n) * sizeof(*x))
#define zero_mem_lth(x,n) memset(x, 0, (n) * sizeof(*x))
init_mem_lth(sd_dsk_arr, sd_template.dev_max);
if (sd_dsk_arr) {
zero_mem_lth(sd_dsk_arr, sd_template.dev_max);
for (k = 0; k < sd_template.dev_max; ++k) {
sdkp = vmalloc(sizeof(Scsi_Disk));
if (NULL == sdkp)
goto cleanup_mem;
memset(sdkp, 0, sizeof(Scsi_Disk));
sd_dsk_arr[k] = sdkp;
}
}
init_mem_lth(sd_disks, sd_template.dev_max);
if (sd_disks)
zero_mem_lth(sd_disks, sd_template.dev_max);
init_mem_lth(sd, maxparts);
if (!sd_dsk_arr || !sd || !sd_disks)
goto cleanup_mem;
zero_mem_lth(sd, maxparts);
return 0;
#undef init_mem_lth
#undef zero_mem_lth
cleanup_mem:
vfree(sd_disks);
sd_disks = NULL;
vfree(sd);
sd = NULL;
if (sd_dsk_arr) {
for (k = 0; k < sd_template.dev_max; ++k)
vfree(sd_dsk_arr[k]);
vfree(sd_dsk_arr);
sd_dsk_arr = NULL;
}
for (k = 0; k < N_USED_SD_MAJORS; k++) {
unregister_blkdev(SD_MAJOR(k), "sd");
}
sd_registered--;
return 1;
}
/**
* sd_finish - called during driver initialization, after all
* the sd_attach() calls are finished.
*
* Note: this function is invoked from the scsi mid-level.
* This function is not called after driver initialization has completed.
* Specifically later device attachments invoke sd_attach() but not
* this function.
**/
static void sd_finish()
{
int k;
Scsi_Disk * sdkp;
SCSI_LOG_HLQUEUE(3, printk("sd_finish: \n"));
for (k = 0; k < N_USED_SD_MAJORS; k++)
blk_dev[SD_MAJOR(k)].queue = sd_find_queue;
for (k = 0; k < sd_template.dev_max; ++k) {
sdkp = sd_get_sdisk(k);
if (sdkp && (0 == sdkp->capacity) && sdkp->device) {
sd_init_onedisk(sdkp, k);
if (!sdkp->has_been_registered) {
add_gendisk(sd_disks[k]);
register_disk(sd_disks[k], MKDEV_SD(k),
1<<4, &sd_fops,
sdkp->capacity);
sdkp->has_been_registered = 1;
}
}
}
return;
}
/**
* sd_detect - called at the start of driver initialization, once
* for each scsi device (not just disks) present.
*
* Returns 0 if not interested in this scsi device (e.g. scanner);
* 1 if this device is of interest (e.g. a disk).
*
* Note: this function is invoked from the scsi mid-level.
* This function is called before sd_init() so very little is available.
**/
static int sd_detect(Scsi_Device * sdp)
{
SCSI_LOG_HLQUEUE(3, printk("sd_detect: type=%d\n", sdp->type));
if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD)
return 0;
sd_template.dev_noticed++;
return 1;
}
/**
* sd_attach - called during driver initialization and whenever a
* new scsi device is attached to the system. It is called once
* for each scsi device (not just disks) present.
* @sdp: pointer to mid level scsi device object
*
* Returns 0 if successful (or not interested in this scsi device
* (e.g. scanner)); 1 when there is an error.
*
* Note: this function is invoked from the scsi mid-level.
* This function sets up the mapping between a given
* <host,channel,id,lun> (found in sdp) and new device name
* (e.g. /dev/sda). More precisely it is the block device major
* and minor number that is chosen here.
**/
static int sd_attach(Scsi_Device * sdp)
{
Scsi_Disk *sdkp;
int dsk_nr;
char diskname[6];
unsigned long iflags;
struct {
struct gendisk disk;
char name[5];
} *p;
struct gendisk *gd;
if ((NULL == sdp) ||
((sdp->type != TYPE_DISK) && (sdp->type != TYPE_MOD)))
return 0;
p = kmalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return 1;
gd = &p->disk;
SCSI_LOG_HLQUEUE(3, printk("sd_attach: scsi device: <%d,%d,%d,%d>\n",
sdp->host->host_no, sdp->channel, sdp->id, sdp->lun));
if (sd_template.nr_dev >= sd_template.dev_max) {
sdp->attached--;
printk(KERN_ERR "sd_init: no more room for device\n");
kfree(p);
return 1;
}
/* Assume sd_attach is not re-entrant (for time being) */
/* Also think about sd_attach() and sd_detach() running coincidentally. */
write_lock_irqsave(&sd_dsk_arr_lock, iflags);
for (dsk_nr = 0; dsk_nr < sd_template.dev_max; dsk_nr++) {
sdkp = sd_dsk_arr[dsk_nr];
if (!sdkp->device) {
memset(sdkp, 0, sizeof(Scsi_Disk));
sdkp->device = sdp;
break;
}
}
write_unlock_irqrestore(&sd_dsk_arr_lock, iflags);
if (dsk_nr >= sd_template.dev_max) {
/* panic("scsi_devices corrupt (sd)"); overkill */
printk(KERN_ERR "sd_init: sd_dsk_arr corrupted\n");
kfree(p);
return 1;
}
sd_template.nr_dev++;
gd->de = sdp->de;
gd->major = SD_MAJOR(dsk_nr>>4);
gd->first_minor = (dsk_nr & 15)<<4;
gd->minor_shift = 4;
gd->part = sd + (dsk_nr << 4);
gd->fops = &sd_fops;
if (dsk_nr > 26)
sprintf(p->name, "sd%c%c", 'a'+dsk_nr/26-1, 'a'+dsk_nr%26);
else
sprintf(p->name, "sd%c", 'a'+dsk_nr%26);
gd->major_name = p->name;
gd->flags = sdp->removable ? GENHD_FL_REMOVABLE : 0;
gd->driverfs_dev = &sdp->sdev_driverfs_dev;
gd->flags |= GENHD_FL_DRIVERFS | GENHD_FL_DEVFS;
sd_disks[dsk_nr] = gd;
sd_dskname(dsk_nr, diskname);
printk(KERN_NOTICE "Attached scsi %sdisk %s at scsi%d, channel %d, "
"id %d, lun %d\n", sdp->removable ? "removable " : "",
diskname, sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
return 0;
}
static int sd_revalidate(kdev_t dev)
{
int dsk_nr = DEVICE_NR(dev);
Scsi_Disk * sdkp = sd_get_sdisk(dsk_nr);
if (!sdkp || !sdkp->device)
return -ENODEV;
sd_init_onedisk(sdkp, dsk_nr);
set_capacity(sd_disks[dsk_nr], sdkp->capacity);
return 0;
}
/**
* sd_detach - called whenever a scsi disk (previously recognized by
* sd_attach) is detached from the system. It is called (potentially
* multiple times) during sd module unload.
* @sdp: pointer to mid level scsi device object
*
* Note: this function is invoked from the scsi mid-level.
* This function potentially frees up a device name (e.g. /dev/sdc)
* that could be re-used by a subsequent sd_attach().
* This function is not called when the built-in sd driver is "exit-ed".
**/
static void sd_detach(Scsi_Device * sdp)
{
Scsi_Disk *sdkp = NULL;
kdev_t dev;
int dsk_nr;
unsigned long iflags;
SCSI_LOG_HLQUEUE(3, printk("sd_detach: <%d,%d,%d,%d>\n",
sdp->host->host_no, sdp->channel, sdp->id,
sdp->lun));
write_lock_irqsave(&sd_dsk_arr_lock, iflags);
for (dsk_nr = 0; dsk_nr < sd_template.dev_max; dsk_nr++) {
sdkp = sd_dsk_arr[dsk_nr];
if (sdkp->device == sdp) {
sdkp->device = NULL;
sdkp->capacity = 0;
/* sdkp->detaching = 1; */
break;
}
}
write_unlock_irqrestore(&sd_dsk_arr_lock, iflags);
if (dsk_nr >= sd_template.dev_max)
return;
if (sdkp->has_been_registered) {
sdkp->has_been_registered = 0;
dev = MKDEV_SD(dsk_nr);
del_gendisk(sd_disks[dsk_nr]);
}
sdp->attached--;
sd_template.dev_noticed--;
sd_template.nr_dev--;
kfree(sd_disks[dsk_nr]);
sd_disks[dsk_nr] = NULL;
}
/**
* init_sd - entry point for this driver (both when built in or when
* a module).
*
* Note: this function registers this driver with the scsi mid-level.
**/
static int __init init_sd(void)
{
int rc;
SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
sd_template.module = THIS_MODULE;
rc = scsi_register_device(&sd_template);
if (!rc) {
sd_template.scsi_driverfs_driver.name = (char *)sd_template.tag;
sd_template.scsi_driverfs_driver.bus = &scsi_driverfs_bus_type;
driver_register(&sd_template.scsi_driverfs_driver);
}
return rc;
}
/**
* exit_sd - exit point for this driver (when it is a module).
*
* Note: this function unregisters this driver from the scsi mid-level.
**/
static void __exit exit_sd(void)
{
int k;
SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
scsi_unregister_device(&sd_template);
for (k = 0; k < N_USED_SD_MAJORS; k++)
unregister_blkdev(SD_MAJOR(k), "sd");
sd_registered--;
if (sd_dsk_arr != NULL) {
for (k = 0; k < sd_template.dev_max; ++k)
vfree(sd_dsk_arr[k]);
vfree(sd_dsk_arr);
}
vfree((char *) sd);
for (k = 0; k < N_USED_SD_MAJORS; k++) {
blk_dev[SD_MAJOR(k)].queue = NULL;
blk_clear(SD_MAJOR(k));
}
sd_template.dev_max = 0;
remove_driver(&sd_template.scsi_driverfs_driver);
}
static Scsi_Disk * sd_get_sdisk(int index)
{
Scsi_Disk * sdkp = NULL;
unsigned long iflags;
read_lock_irqsave(&sd_dsk_arr_lock, iflags);
if (sd_dsk_arr && (index >= 0) && (index < sd_template.dev_max))
sdkp = sd_dsk_arr[index];
read_unlock_irqrestore(&sd_dsk_arr_lock, iflags);
return sdkp;
}
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Eric Youngdale");
MODULE_DESCRIPTION("SCSI disk (sd) driver");
module_init(init_sd);
module_exit(exit_sd);