/
sd.c
1911 lines (1652 loc) · 50.2 KB
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sd.c
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/*
* 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.x
* - Badari Pulavarty <pbadari@us.ibm.com>, Matthew Wilcox
* <willy@debian.org>, Kurt Garloff <garloff@suse.de>:
* Support 32k/1M disks.
*
* 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/module.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/bio.h>
#include <linux/genhd.h>
#include <linux/hdreg.h>
#include <linux/errno.h>
#include <linux/idr.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/blkpg.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <asm/uaccess.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsicam.h>
#include <scsi/sd.h>
#include "scsi_logging.h"
MODULE_AUTHOR("Eric Youngdale");
MODULE_DESCRIPTION("SCSI disk (sd) driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
static DEFINE_IDR(sd_index_idr);
static DEFINE_SPINLOCK(sd_index_lock);
/* This semaphore is used to mediate the 0->1 reference get in the
* face of object destruction (i.e. we can't allow a get on an
* object after last put) */
static DEFINE_MUTEX(sd_ref_mutex);
static const char *sd_cache_types[] = {
"write through", "none", "write back",
"write back, no read (daft)"
};
static ssize_t sd_store_cache_type(struct class_device *cdev, const char *buf,
size_t count)
{
int i, ct = -1, rcd, wce, sp;
struct scsi_disk *sdkp = to_scsi_disk(cdev);
struct scsi_device *sdp = sdkp->device;
char buffer[64];
char *buffer_data;
struct scsi_mode_data data;
struct scsi_sense_hdr sshdr;
int len;
if (sdp->type != TYPE_DISK)
/* no cache control on RBC devices; theoretically they
* can do it, but there's probably so many exceptions
* it's not worth the risk */
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
const int len = strlen(sd_cache_types[i]);
if (strncmp(sd_cache_types[i], buf, len) == 0 &&
buf[len] == '\n') {
ct = i;
break;
}
}
if (ct < 0)
return -EINVAL;
rcd = ct & 0x01 ? 1 : 0;
wce = ct & 0x02 ? 1 : 0;
if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
SD_MAX_RETRIES, &data, NULL))
return -EINVAL;
len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
data.block_descriptor_length);
buffer_data = buffer + data.header_length +
data.block_descriptor_length;
buffer_data[2] &= ~0x05;
buffer_data[2] |= wce << 2 | rcd;
sp = buffer_data[0] & 0x80 ? 1 : 0;
if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
SD_MAX_RETRIES, &data, &sshdr)) {
if (scsi_sense_valid(&sshdr))
sd_print_sense_hdr(sdkp, &sshdr);
return -EINVAL;
}
sd_revalidate_disk(sdkp->disk);
return count;
}
static ssize_t sd_store_manage_start_stop(struct class_device *cdev,
const char *buf, size_t count)
{
struct scsi_disk *sdkp = to_scsi_disk(cdev);
struct scsi_device *sdp = sdkp->device;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
return count;
}
static ssize_t sd_store_allow_restart(struct class_device *cdev, const char *buf,
size_t count)
{
struct scsi_disk *sdkp = to_scsi_disk(cdev);
struct scsi_device *sdp = sdkp->device;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (sdp->type != TYPE_DISK)
return -EINVAL;
sdp->allow_restart = simple_strtoul(buf, NULL, 10);
return count;
}
static ssize_t sd_show_cache_type(struct class_device *cdev, char *buf)
{
struct scsi_disk *sdkp = to_scsi_disk(cdev);
int ct = sdkp->RCD + 2*sdkp->WCE;
return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
}
static ssize_t sd_show_fua(struct class_device *cdev, char *buf)
{
struct scsi_disk *sdkp = to_scsi_disk(cdev);
return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
}
static ssize_t sd_show_manage_start_stop(struct class_device *cdev, char *buf)
{
struct scsi_disk *sdkp = to_scsi_disk(cdev);
struct scsi_device *sdp = sdkp->device;
return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
}
static ssize_t sd_show_allow_restart(struct class_device *cdev, char *buf)
{
struct scsi_disk *sdkp = to_scsi_disk(cdev);
return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
}
static struct class_device_attribute sd_disk_attrs[] = {
__ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
sd_store_cache_type),
__ATTR(FUA, S_IRUGO, sd_show_fua, NULL),
__ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart,
sd_store_allow_restart),
__ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
sd_store_manage_start_stop),
__ATTR_NULL,
};
static struct class sd_disk_class = {
.name = "scsi_disk",
.owner = THIS_MODULE,
.release = scsi_disk_release,
.class_dev_attrs = sd_disk_attrs,
};
static struct scsi_driver sd_template = {
.owner = THIS_MODULE,
.gendrv = {
.name = "sd",
.probe = sd_probe,
.remove = sd_remove,
.suspend = sd_suspend,
.resume = sd_resume,
.shutdown = sd_shutdown,
},
.rescan = sd_rescan,
.init_command = sd_init_command,
};
/*
* Device no to disk mapping:
*
* major disc2 disc p1
* |............|.............|....|....| <- dev_t
* 31 20 19 8 7 4 3 0
*
* Inside a major, we have 16k disks, however mapped non-
* contiguously. The first 16 disks are for major0, the next
* ones with major1, ... Disk 256 is for major0 again, disk 272
* for major1, ...
* As we stay compatible with our numbering scheme, we can reuse
* the well-know SCSI majors 8, 65--71, 136--143.
*/
static int sd_major(int major_idx)
{
switch (major_idx) {
case 0:
return SCSI_DISK0_MAJOR;
case 1 ... 7:
return SCSI_DISK1_MAJOR + major_idx - 1;
case 8 ... 15:
return SCSI_DISK8_MAJOR + major_idx - 8;
default:
BUG();
return 0; /* shut up gcc */
}
}
static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
{
return container_of(disk->private_data, struct scsi_disk, driver);
}
static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
{
struct scsi_disk *sdkp = NULL;
if (disk->private_data) {
sdkp = scsi_disk(disk);
if (scsi_device_get(sdkp->device) == 0)
class_device_get(&sdkp->cdev);
else
sdkp = NULL;
}
return sdkp;
}
static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
{
struct scsi_disk *sdkp;
mutex_lock(&sd_ref_mutex);
sdkp = __scsi_disk_get(disk);
mutex_unlock(&sd_ref_mutex);
return sdkp;
}
static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
{
struct scsi_disk *sdkp;
mutex_lock(&sd_ref_mutex);
sdkp = dev_get_drvdata(dev);
if (sdkp)
sdkp = __scsi_disk_get(sdkp->disk);
mutex_unlock(&sd_ref_mutex);
return sdkp;
}
static void scsi_disk_put(struct scsi_disk *sdkp)
{
struct scsi_device *sdev = sdkp->device;
mutex_lock(&sd_ref_mutex);
class_device_put(&sdkp->cdev);
scsi_device_put(sdev);
mutex_unlock(&sd_ref_mutex);
}
/**
* 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(struct scsi_cmnd * SCpnt)
{
struct scsi_device *sdp = SCpnt->device;
struct request *rq = SCpnt->request;
struct gendisk *disk = rq->rq_disk;
sector_t block = rq->sector;
unsigned int this_count = SCpnt->request_bufflen >> 9;
unsigned int timeout = sdp->timeout;
SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
"sd_init_command: block=%llu, "
"count=%d\n",
(unsigned long long)block,
this_count));
if (!sdp || !scsi_device_online(sdp) ||
block + rq->nr_sectors > get_capacity(disk)) {
SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
"Finishing %ld sectors\n",
rq->nr_sectors));
SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
"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, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
(unsigned long long)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) || (rq->nr_sectors & 1)) {
scmd_printk(KERN_ERR, SCpnt,
"Bad block number requested\n");
return 0;
} else {
block = block >> 1;
this_count = this_count >> 1;
}
}
if (sdp->sector_size == 2048) {
if ((block & 3) || (rq->nr_sectors & 3)) {
scmd_printk(KERN_ERR, SCpnt,
"Bad block number requested\n");
return 0;
} else {
block = block >> 2;
this_count = this_count >> 2;
}
}
if (sdp->sector_size == 4096) {
if ((block & 7) || (rq->nr_sectors & 7)) {
scmd_printk(KERN_ERR, SCpnt,
"Bad block number requested\n");
return 0;
} else {
block = block >> 3;
this_count = this_count >> 3;
}
}
if (rq_data_dir(rq) == WRITE) {
if (!sdp->writeable) {
return 0;
}
SCpnt->cmnd[0] = WRITE_6;
SCpnt->sc_data_direction = DMA_TO_DEVICE;
} else if (rq_data_dir(rq) == READ) {
SCpnt->cmnd[0] = READ_6;
SCpnt->sc_data_direction = DMA_FROM_DEVICE;
} else {
scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
return 0;
}
SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
"%s %d/%ld 512 byte blocks.\n",
(rq_data_dir(rq) == WRITE) ?
"writing" : "reading", this_count,
rq->nr_sectors));
SCpnt->cmnd[1] = 0;
if (block > 0xffffffff) {
SCpnt->cmnd[0] += READ_16 - READ_6;
SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
SCpnt->cmnd[9] = (unsigned char) block & 0xff;
SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
} else if ((this_count > 0xff) || (block > 0x1fffff) ||
SCpnt->device->use_10_for_rw) {
if (this_count > 0xffff)
this_count = 0xffff;
SCpnt->cmnd[0] += READ_10 - READ_6;
SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
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 (unlikely(blk_fua_rq(rq))) {
/*
* This happens only if this drive failed
* 10byte rw command with ILLEGAL_REQUEST
* during operation and thus turned off
* use_10_for_rw.
*/
scmd_printk(KERN_ERR, SCpnt,
"FUA write on READ/WRITE(6) drive\n");
return 0;
}
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;
}
SCpnt->request_bufflen = this_count * sdp->sector_size;
/*
* 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 = SD_MAX_RETRIES;
SCpnt->timeout_per_command = 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)
{
struct gendisk *disk = inode->i_bdev->bd_disk;
struct scsi_disk *sdkp;
struct scsi_device *sdev;
int retval;
if (!(sdkp = scsi_disk_get(disk)))
return -ENXIO;
SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
sdev = sdkp->device;
/*
* If the device is in error recovery, wait until it is done.
* If the device is offline, then disallow any access to it.
*/
retval = -ENXIO;
if (!scsi_block_when_processing_errors(sdev))
goto error_out;
if (sdev->removable || sdkp->write_prot)
check_disk_change(inode->i_bdev);
/*
* If the drive is empty, just let the open fail.
*/
retval = -ENOMEDIUM;
if (sdev->removable && !sdkp->media_present &&
!(filp->f_flags & O_NDELAY))
goto error_out;
/*
* 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.
*/
retval = -EROFS;
if (sdkp->write_prot && (filp->f_mode & FMODE_WRITE))
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.
*/
retval = -ENXIO;
if (!scsi_device_online(sdev))
goto error_out;
if (!sdkp->openers++ && sdev->removable) {
if (scsi_block_when_processing_errors(sdev))
scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
}
return 0;
error_out:
scsi_disk_put(sdkp);
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)
{
struct gendisk *disk = inode->i_bdev->bd_disk;
struct scsi_disk *sdkp = scsi_disk(disk);
struct scsi_device *sdev = sdkp->device;
SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
if (!--sdkp->openers && sdev->removable) {
if (scsi_block_when_processing_errors(sdev))
scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
}
/*
* XXX and what if there are packets in flight and this close()
* XXX is followed by a "rmmod sd_mod"?
*/
scsi_disk_put(sdkp);
return 0;
}
static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
struct scsi_device *sdp = sdkp->device;
struct Scsi_Host *host = sdp->host;
int diskinfo[4];
/* 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)
host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
else
scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
geo->heads = diskinfo[0];
geo->sectors = diskinfo[1];
geo->cylinders = diskinfo[2];
return 0;
}
/**
* sd_ioctl - process an ioctl
* @inode: only i_rdev/i_bdev members 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)
{
struct block_device *bdev = inode->i_bdev;
struct gendisk *disk = bdev->bd_disk;
struct scsi_device *sdp = scsi_disk(disk)->device;
void __user *p = (void __user *)arg;
int error;
SCSI_LOG_IOCTL(1, printk("sd_ioctl: disk=%s, cmd=0x%x\n",
disk->disk_name, cmd));
/*
* 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.
*/
error = scsi_nonblockable_ioctl(sdp, cmd, p, filp);
if (!scsi_block_when_processing_errors(sdp) || !error)
return error;
/*
* Send SCSI addressing ioctls directly to mid level, send other
* ioctls to block level and then onto mid level if they can't be
* resolved.
*/
switch (cmd) {
case SCSI_IOCTL_GET_IDLUN:
case SCSI_IOCTL_GET_BUS_NUMBER:
return scsi_ioctl(sdp, cmd, p);
default:
error = scsi_cmd_ioctl(filp, disk->queue, disk, cmd, p);
if (error != -ENOTTY)
return error;
}
return scsi_ioctl(sdp, cmd, p);
}
static void set_media_not_present(struct scsi_disk *sdkp)
{
sdkp->media_present = 0;
sdkp->capacity = 0;
sdkp->device->changed = 1;
}
/**
* sd_media_changed - check if our medium changed
* @disk: kernel device descriptor
*
* Returns 0 if not applicable or no change; 1 if change
*
* Note: this function is invoked from the block subsystem.
**/
static int sd_media_changed(struct gendisk *disk)
{
struct scsi_disk *sdkp = scsi_disk(disk);
struct scsi_device *sdp = sdkp->device;
int retval;
SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_media_changed\n"));
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 (!scsi_device_online(sdp))
goto not_present;
/*
* Using TEST_UNIT_READY enables differentiation between drive with
* no cartridge loaded - NOT READY, drive with changed cartridge -
* UNIT ATTENTION, or with same cartridge - GOOD STATUS.
*
* Drives that auto spin down. eg iomega jaz 1G, will be started
* by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
* sd_revalidate() is called.
*/
retval = -ENODEV;
if (scsi_block_when_processing_errors(sdp))
retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES);
/*
* 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.
*/
if (retval)
goto not_present;
/*
* For removable scsi disk we have to recognise the presence
* of a disk in the drive. This is kept in the struct scsi_disk
* struct and tested at open ! Daniel Roche (dan@lectra.fr)
*/
sdkp->media_present = 1;
retval = sdp->changed;
sdp->changed = 0;
return retval;
not_present:
set_media_not_present(sdkp);
return 1;
}
static int sd_sync_cache(struct scsi_disk *sdkp)
{
int retries, res;
struct scsi_device *sdp = sdkp->device;
struct scsi_sense_hdr sshdr;
if (!scsi_device_online(sdp))
return -ENODEV;
for (retries = 3; retries > 0; --retries) {
unsigned char cmd[10] = { 0 };
cmd[0] = SYNCHRONIZE_CACHE;
/*
* Leave the rest of the command zero to indicate
* flush everything.
*/
res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
SD_TIMEOUT, SD_MAX_RETRIES);
if (res == 0)
break;
}
if (res) {
sd_print_result(sdkp, res);
if (driver_byte(res) & DRIVER_SENSE)
sd_print_sense_hdr(sdkp, &sshdr);
}
if (res)
return -EIO;
return 0;
}
static int sd_issue_flush(struct request_queue *q, struct gendisk *disk,
sector_t *error_sector)
{
int ret = 0;
struct scsi_device *sdp = q->queuedata;
struct scsi_disk *sdkp;
if (sdp->sdev_state != SDEV_RUNNING)
return -ENXIO;
sdkp = scsi_disk_get_from_dev(&sdp->sdev_gendev);
if (!sdkp)
return -ENODEV;
if (sdkp->WCE)
ret = sd_sync_cache(sdkp);
scsi_disk_put(sdkp);
return ret;
}
static void sd_prepare_flush(struct request_queue *q, struct request *rq)
{
memset(rq->cmd, 0, sizeof(rq->cmd));
rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->timeout = SD_TIMEOUT;
rq->cmd[0] = SYNCHRONIZE_CACHE;
rq->cmd_len = 10;
}
static void sd_rescan(struct device *dev)
{
struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
if (sdkp) {
sd_revalidate_disk(sdkp->disk);
scsi_disk_put(sdkp);
}
}
#ifdef CONFIG_COMPAT
/*
* This gets directly called from VFS. When the ioctl
* is not recognized we go back to the other translation paths.
*/
static long sd_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct block_device *bdev = file->f_path.dentry->d_inode->i_bdev;
struct gendisk *disk = bdev->bd_disk;
struct scsi_device *sdev = scsi_disk(disk)->device;
/*
* 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(sdev))
return -ENODEV;
if (sdev->host->hostt->compat_ioctl) {
int ret;
ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
return ret;
}
/*
* Let the static ioctl translation table take care of it.
*/
return -ENOIOCTLCMD;
}
#endif
static struct block_device_operations sd_fops = {
.owner = THIS_MODULE,
.open = sd_open,
.release = sd_release,
.ioctl = sd_ioctl,
.getgeo = sd_getgeo,
#ifdef CONFIG_COMPAT
.compat_ioctl = sd_compat_ioctl,
#endif
.media_changed = sd_media_changed,
.revalidate_disk = sd_revalidate_disk,
};
/**
* 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(struct scsi_cmnd * SCpnt)
{
int result = SCpnt->result;
unsigned int xfer_size = SCpnt->request_bufflen;
unsigned int good_bytes = result ? 0 : xfer_size;
u64 start_lba = SCpnt->request->sector;
u64 bad_lba;
struct scsi_sense_hdr sshdr;
int sense_valid = 0;
int sense_deferred = 0;
int info_valid;
if (result) {
sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
if (sense_valid)
sense_deferred = scsi_sense_is_deferred(&sshdr);
}
#ifdef CONFIG_SCSI_LOGGING
SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
if (sense_valid) {
SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
"sd_rw_intr: sb[respc,sk,asc,"
"ascq]=%x,%x,%x,%x\n",
sshdr.response_code,
sshdr.sense_key, sshdr.asc,
sshdr.ascq));
}
#endif
if (driver_byte(result) != DRIVER_SENSE &&
(!sense_valid || sense_deferred))
goto out;
switch (sshdr.sense_key) {
case HARDWARE_ERROR:
case MEDIUM_ERROR:
if (!blk_fs_request(SCpnt->request))
goto out;
info_valid = scsi_get_sense_info_fld(SCpnt->sense_buffer,
SCSI_SENSE_BUFFERSIZE,
&bad_lba);
if (!info_valid)
goto out;
if (xfer_size <= SCpnt->device->sector_size)
goto out;
switch (SCpnt->device->sector_size) {
case 256:
start_lba <<= 1;
break;
case 512:
break;
case 1024:
start_lba >>= 1;
break;
case 2048:
start_lba >>= 2;
break;
case 4096:
start_lba >>= 3;
break;
default:
/* Print something here with limiting frequency. */
goto out;
break;
}
/* This computation should always be done in terms of
* the resolution of the device's medium.
*/
good_bytes = (bad_lba - start_lba)*SCpnt->device->sector_size;
break;
case RECOVERED_ERROR:
case NO_SENSE:
/* Inform the user, but make sure that it's not treated
* as a hard error.
*/
scsi_print_sense("sd", SCpnt);
SCpnt->result = 0;
memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
good_bytes = xfer_size;
break;
case ILLEGAL_REQUEST:
if (SCpnt->device->use_10_for_rw &&
(SCpnt->cmnd[0] == READ_10 ||
SCpnt->cmnd[0] == WRITE_10))
SCpnt->device->use_10_for_rw = 0;
if (SCpnt->device->use_10_for_ms &&
(SCpnt->cmnd[0] == MODE_SENSE_10 ||
SCpnt->cmnd[0] == MODE_SELECT_10))
SCpnt->device->use_10_for_ms = 0;
break;
default:
break;
}
out:
scsi_io_completion(SCpnt, good_bytes);
}
static int media_not_present(struct scsi_disk *sdkp,
struct scsi_sense_hdr *sshdr)
{
if (!scsi_sense_valid(sshdr))
return 0;
/* not invoked for commands that could return deferred errors */