/* * 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/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/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/kref.h> #include <linux/delay.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/scsi_request.h> #include <scsi/scsicam.h> #include "scsi_logging.h" /* * More than enough for everybody ;) The huge number of majors * is a leftover from 16bit dev_t days, we don't really need that * much numberspace. */ #define SD_MAJORS 16 /* * This is limited by the naming scheme enforced in sd_probe, * add another character to it if you really need more disks. */ #define SD_MAX_DISKS (((26 * 26) + 26 + 1) * 26) /* * Time out in seconds for disks and Magneto-opticals (which are slower). */ #define SD_TIMEOUT (30 * HZ) #define SD_MOD_TIMEOUT (75 * HZ) /* * Number of allowed retries */ #define SD_MAX_RETRIES 5 #define SD_PASSTHROUGH_RETRIES 1 static void scsi_disk_release(struct kref *kref); struct scsi_disk { struct scsi_driver *driver; /* always &sd_template */ struct scsi_device *device; struct kref kref; struct gendisk *disk; unsigned int openers; /* protected by BKL for now, yuck */ sector_t capacity; /* size in 512-byte sectors */ u32 index; u8 media_present; u8 write_prot; unsigned WCE : 1; /* state of disk WCE bit */ unsigned RCD : 1; /* state of disk RCD bit, unused */ }; 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 DECLARE_MUTEX(sd_ref_sem); static int sd_revalidate_disk(struct gendisk *disk); static void sd_rw_intr(struct scsi_cmnd * SCpnt); static int sd_probe(struct device *); static int sd_remove(struct device *); static void sd_shutdown(struct device *dev); static void sd_rescan(struct device *); static int sd_init_command(struct scsi_cmnd *); static int sd_issue_flush(struct device *, sector_t *); static void sd_end_flush(request_queue_t *, struct request *); static int sd_prepare_flush(request_queue_t *, struct request *); static void sd_read_capacity(struct scsi_disk *sdkp, char *diskname, struct scsi_request *SRpnt, unsigned char *buffer); static struct scsi_driver sd_template = { .owner = THIS_MODULE, .gendrv = { .name = "sd", .probe = sd_probe, .remove = sd_remove, .shutdown = sd_shutdown, }, .rescan = sd_rescan, .init_command = sd_init_command, .issue_flush = sd_issue_flush, .prepare_flush = sd_prepare_flush, .end_flush = sd_end_flush, }; /* * 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 */ } } #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,kref) 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; down(&sd_ref_sem); if (disk->private_data == NULL) goto out; sdkp = scsi_disk(disk); kref_get(&sdkp->kref); if (scsi_device_get(sdkp->device)) goto out_put; up(&sd_ref_sem); return sdkp; out_put: kref_put(&sdkp->kref, scsi_disk_release); sdkp = NULL; out: up(&sd_ref_sem); return sdkp; } static void scsi_disk_put(struct scsi_disk *sdkp) { struct scsi_device *sdev = sdkp->device; down(&sd_ref_sem); kref_put(&sdkp->kref, scsi_disk_release); scsi_device_put(sdev); up(&sd_ref_sem); } /** * 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) { unsigned int this_count, timeout; struct gendisk *disk; sector_t block; struct scsi_device *sdp = SCpnt->device; struct request *rq = SCpnt->request; timeout = sdp->timeout; /* * SG_IO from block layer already setup, just copy cdb basically */ if (blk_pc_request(rq)) { if (sizeof(rq->cmd) > sizeof(SCpnt->cmnd)) return 0; memcpy(SCpnt->cmnd, rq->cmd, sizeof(SCpnt->cmnd)); if (rq_data_dir(rq) == WRITE) SCpnt->sc_data_direction = DMA_TO_DEVICE; else if (rq->data_len) SCpnt->sc_data_direction = DMA_FROM_DEVICE; else SCpnt->sc_data_direction = DMA_NONE; this_count = rq->data_len; if (rq->timeout) timeout = rq->timeout; SCpnt->transfersize = rq->data_len; SCpnt->allowed = SD_PASSTHROUGH_RETRIES; goto queue; } /* * we only do REQ_CMD and REQ_BLOCK_PC */ if (!blk_fs_request(rq)) return 0; disk = rq->rq_disk; block = rq->sector; this_count = SCpnt->request_bufflen >> 9; SCSI_LOG_HLQUEUE(1, printk("sd_init_command: disk=%s, block=%llu, " "count=%d\n", disk->disk_name, (unsigned long long)block, this_count)); if (!sdp || !scsi_device_online(sdp) || block + rq->nr_sectors > get_capacity(disk)) { SCSI_LOG_HLQUEUE(2, printk("Finishing %ld sectors\n", rq->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, printk("%s : block=%llu\n", disk->disk_name, (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)) { 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) || (rq->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) || (rq->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(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 { printk(KERN_ERR "sd: Unknown command %lx\n", rq->flags); /* overkill panic("Unknown sd command %lx\n", rq->flags); */ return 0; } SCSI_LOG_HLQUEUE(2, printk("%s : %s %d/%ld 512 byte blocks.\n", disk->disk_name, (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[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[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 { 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 = SCpnt->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; queue: 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, printk("sd_open: disk=%s\n", disk->disk_name)); 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, printk("sd_release: disk=%s\n", disk->disk_name)); 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_hdio_getgeo(struct block_device *bdev, struct hd_geometry __user *loc) { 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); if (put_user(diskinfo[0], &loc->heads)) return -EFAULT; if (put_user(diskinfo[1], &loc->sectors)) return -EFAULT; if (put_user(diskinfo[2], &loc->cylinders)) return -EFAULT; if (put_user((unsigned)get_start_sect(bdev), (unsigned long __user *)&loc->start)) return -EFAULT; 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; if (cmd == HDIO_GETGEO) { if (!arg) return -EINVAL; return sd_hdio_getgeo(bdev, p); } /* * 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, 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, printk("sd_media_changed: disk=%s\n", disk->disk_name)); 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_device *sdp) { struct scsi_request *sreq; int retries, res; if (!scsi_device_online(sdp)) return -ENODEV; sreq = scsi_allocate_request(sdp, GFP_KERNEL); if (!sreq) { printk("FAILED\n No memory for request\n"); return -ENOMEM; } sreq->sr_data_direction = DMA_NONE; 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. */ scsi_wait_req(sreq, cmd, NULL, 0, SD_TIMEOUT, SD_MAX_RETRIES); if (sreq->sr_result == 0) break; } res = sreq->sr_result; if (res) { printk(KERN_WARNING "FAILED\n status = %x, message = %02x, " "host = %d, driver = %02x\n ", status_byte(res), msg_byte(res), host_byte(res), driver_byte(res)); if (driver_byte(res) & DRIVER_SENSE) scsi_print_req_sense("sd", sreq); } scsi_release_request(sreq); return res; } static int sd_issue_flush(struct device *dev, sector_t *error_sector) { struct scsi_device *sdp = to_scsi_device(dev); struct scsi_disk *sdkp = dev_get_drvdata(dev); if (!sdkp) return -ENODEV; if (!sdkp->WCE) return 0; return sd_sync_cache(sdp); } static void sd_end_flush(request_queue_t *q, struct request *flush_rq) { struct request *rq = flush_rq->end_io_data; struct scsi_cmnd *cmd = rq->special; unsigned int bytes = rq->hard_nr_sectors << 9; if (!flush_rq->errors) { spin_unlock(q->queue_lock); scsi_io_completion(cmd, bytes, 0); spin_lock(q->queue_lock); } else if (blk_barrier_postflush(rq)) { spin_unlock(q->queue_lock); scsi_io_completion(cmd, 0, bytes); spin_lock(q->queue_lock); } else { /* * force journal abort of barriers */ end_that_request_first(rq, -EOPNOTSUPP, rq->hard_nr_sectors); end_that_request_last(rq); } } static int sd_prepare_flush(request_queue_t *q, struct request *rq) { struct scsi_device *sdev = q->queuedata; struct scsi_disk *sdkp = dev_get_drvdata(&sdev->sdev_gendev); if (sdkp->WCE) { memset(rq->cmd, 0, sizeof(rq->cmd)); rq->flags |= REQ_BLOCK_PC | REQ_SOFTBARRIER; rq->timeout = SD_TIMEOUT; rq->cmd[0] = SYNCHRONIZE_CACHE; return 1; } return 0; } static void sd_rescan(struct device *dev) { struct scsi_disk *sdkp = dev_get_drvdata(dev); sd_revalidate_disk(sdkp->disk); } #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_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, #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; int this_count = SCpnt->bufflen; int good_bytes = (result == 0 ? this_count : 0); sector_t block_sectors = 1; u64 first_err_block; sector_t error_sector; 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, printk("sd_rw_intr: %s: res=0x%x\n", SCpnt->request->rq_disk->disk_name, result)); if (sense_valid) { SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: sb[respc,sk,asc," "ascq]=%x,%x,%x,%x\n", sshdr.response_code, sshdr.sense_key, sshdr.asc, sshdr.ascq)); } #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 SG_IO from block layer then set good_bytes to stop retries; * else if errors, check them, and if necessary prepare for * (partial) retries. */ if (blk_pc_request(SCpnt->request)) good_bytes = this_count; else if (driver_byte(result) != 0 && sense_valid && !sense_deferred) { switch (sshdr.sense_key) { case MEDIUM_ERROR: if (!blk_fs_request(SCpnt->request)) break; info_valid = scsi_get_sense_info_fld( SCpnt->sense_buffer, SCSI_SENSE_BUFFERSIZE, &first_err_block); /* * May want to warn and skip if following cast results * in actual truncation (if sector_t < 64 bits) */ error_sector = (sector_t)first_err_block; 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_bytes = (error_sector - SCpnt->request->sector) << 9; if (good_bytes < 0 || good_bytes >= this_count) good_bytes = 0; break; case RECOVERED_ERROR: /* an error occurred, but it recovered */ case NO_SENSE: /* LLDD got sense data */ /* * 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 = this_count; 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; } } /* * 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_bytes, block_sectors << 9); } static int media_not_present(struct scsi_disk *sdkp, struct scsi_request *srp) { struct scsi_sense_hdr sshdr; if (!srp->sr_result) return 0; if (!(driver_byte(srp->sr_result) & DRIVER_SENSE)) return 0; /* not invoked for commands that could return deferred errors */ if (scsi_request_normalize_sense(srp, &sshdr)) { if (sshdr.sense_key != NOT_READY && sshdr.sense_key != UNIT_ATTENTION) return 0; if (sshdr.asc != 0x3A) /* medium not present */ return 0; } set_media_not_present(sdkp); return 1; } /* * spinup disk - called only in sd_revalidate_disk() */ static void sd_spinup_disk(struct scsi_disk *sdkp, char *diskname, struct scsi_request *SRpnt, unsigned char *buffer) { unsigned char cmd[10]; unsigned long spintime_value = 0; int retries, spintime; unsigned int the_result; struct scsi_sense_hdr sshdr; int sense_valid = 0; 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; do { cmd[0] = TEST_UNIT_READY; memset((void *) &cmd[1], 0, 9); SRpnt->sr_cmd_len = 0; memset(SRpnt->sr_sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); SRpnt->sr_data_direction = DMA_NONE; scsi_wait_req (SRpnt, (void *) cmd, (void *) buffer, 0/*512*/, SD_TIMEOUT, SD_MAX_RETRIES); the_result = SRpnt->sr_result; if (the_result) sense_valid = scsi_request_normalize_sense( SRpnt, &sshdr); retries++; } while (retries < 3 && (!scsi_status_is_good(the_result) || ((driver_byte(the_result) & DRIVER_SENSE) && sense_valid && sshdr.sense_key == UNIT_ATTENTION))); /* * 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 (media_not_present(sdkp, SRpnt)) return; if ((driver_byte(the_result) & DRIVER_SENSE) == 0) { /* no sense, TUR either succeeded or failed * with a status error */ if(!spintime && !scsi_status_is_good(the_result)) printk(KERN_NOTICE "%s: Unit Not Ready, " "error = 0x%x\n", diskname, the_result); break; } /* * The device does not want the automatic start to be issued. */ if (sdkp->device->no_start_on_add) { break; } /* * If manual intervention is required, or this is an * absent USB storage device, a spinup is meaningless. */ if (sense_valid && sshdr.sense_key == NOT_READY && sshdr.asc == 4 && sshdr.ascq == 3) { break; /* manual intervention required */ /* * Issue command to spin up drive when not ready */ } else if (sense_valid && sshdr.sense_key == NOT_READY) { if (!spintime) { printk(KERN_NOTICE "%s: Spinning up disk...", diskname); cmd[0] = START_STOP; cmd[1] = 1; /* Return immediately */ memset((void *) &cmd[2], 0, 8); cmd[4] = 1; /* Start spin cycle */ SRpnt->sr_cmd_len = 0; memset(SRpnt->sr_sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); SRpnt->sr_data_direction = DMA_NONE; scsi_wait_req(SRpnt, (void *)cmd, (void *) buffer, 0/*512*/, SD_TIMEOUT, SD_MAX_RETRIES); spintime_value = jiffies; } spintime = 1; /* Wait 1 second for next try */ msleep(1000); printk("."); } else { /* we don't understand the sense code, so it's * probably pointless to loop */ if(!spintime) { printk(KERN_NOTICE "%s: Unit Not Ready, " "sense:\n", diskname); scsi_print_req_sense("", SRpnt); } break; } } while (spintime && time_after(spintime_value + 100 * HZ, jiffies)); if (spintime) { if (scsi_status_is_good(the_result)) printk("ready\n"); else printk("not responding...\n"); } } /* * read disk capacity */ static void sd_read_capacity(struct scsi_disk *sdkp, char *diskname, struct scsi_request *SRpnt, unsigned char *buffer) { unsigned char cmd[16]; struct scsi_device *sdp = sdkp->device; int the_result, retries; int sector_size = 0; int longrc = 0; struct scsi_sense_hdr sshdr; int sense_valid = 0; repeat: retries = 3; do { if (longrc) { memset((void *) cmd, 0, 16); cmd[0] = SERVICE_ACTION_IN; cmd[1] = SAI_READ_CAPACITY_16; cmd[13] = 12; memset((void *) buffer, 0, 12); } else { cmd[0] = READ_CAPACITY; memset((void *) &cmd[1], 0, 9); memset((void *) buffer, 0, 8); } SRpnt->sr_cmd_len = 0; memset(SRpnt->sr_sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); SRpnt->sr_data_direction = DMA_FROM_DEVICE; scsi_wait_req(SRpnt, (void *) cmd, (void *) buffer, longrc ? 12 : 8, SD_TIMEOUT, SD_MAX_RETRIES); if (media_not_present(sdkp, SRpnt)) return; the_result = SRpnt->sr_result; if (the_result) sense_valid = scsi_request_normalize_sense(SRpnt, &sshdr); retries--; } while (the_result && retries); if (the_result && !longrc) { 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) scsi_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 && sense_valid && sshdr.sense_key == NOT_READY) sdp->changed = 1; /* Either no media are present but the drive didn't 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; } else if (the_result && longrc) { /* READ CAPACITY(16) has been failed */ printk(KERN_NOTICE "%s : READ CAPACITY(16) 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)); printk(KERN_NOTICE "%s : use 0xffffffff as device size\n", diskname); sdkp->capacity = 1 + (sector_t) 0xffffffff; goto got_data; } if (!longrc) { sector_size = (buffer[4] << 24) | (buffer[5] << 16) | (buffer[6] << 8) | buffer[7]; if (buffer[0] == 0xff && buffer[1] == 0xff && buffer[2] == 0xff && buffer[3] == 0xff) { if(sizeof(sdkp->capacity) > 4) { printk(KERN_NOTICE "%s : very big device. try to use" " READ CAPACITY(16).\n", diskname); longrc = 1; goto repeat; } printk(KERN_ERR "%s: too big for this kernel. Use a " "kernel compiled with support for large block " "devices.\n", diskname); sdkp->capacity = 0; goto got_data; } sdkp->capacity = 1 + (((sector_t)buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]); } else { sdkp->capacity = 1 + (((u64)buffer[0] << 56) | ((u64)buffer[1] << 48) | ((u64)buffer[2] << 40) | ((u64)buffer[3] << 32) | ((sector_t)buffer[4] << 24) | ((sector_t)buffer[5] << 16) | ((sector_t)buffer[6] << 8) | (sector_t)buffer[7]); sector_size = (buffer[8] << 24) | (buffer[9] << 16) | (buffer[10] << 8) | buffer[11]; } /* Some devices return the total number of sectors, not the * highest sector number. Make the necessary adjustment. */ if (sdp->fix_capacity) --sdkp->capacity; got_data: 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; /* * set a bogus sector size so the normal read/write * logic in the block layer will eventually refuse any * request on this device without tripping over power * of two sector size assumptions */ sector_size = 512; } { /* * 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; sector_t sz = sdkp->capacity * (hard_sector/256); request_queue_t *queue = sdp->request_queue; sector_t mb; blk_queue_hardsect_size(queue, hard_sector); /* avoid 64-bit division on 32-bit platforms */ mb = sz >> 1; sector_div(sz, 1250); mb -= sz - 974; sector_div(mb, 1950); printk(KERN_NOTICE "SCSI device %s: " "%llu %d-byte hdwr sectors (%llu MB)\n", diskname, (unsigned long long)sdkp->capacity, hard_sector, (unsigned long long)mb); } /* Rescale capacity to 512-byte units */ if (sector_size == 4096) sdkp->capacity <<= 3; else if (sector_size == 2048) sdkp->capacity <<= 2; else if (sector_size == 1024) sdkp->capacity <<= 1; else if (sector_size == 256) sdkp->capacity >>= 1; sdkp->device->sector_size = sector_size; } /* called with buffer of length 512 */ static inline int sd_do_mode_sense(struct scsi_request *SRpnt, int dbd, int modepage, unsigned char *buffer, int len, struct scsi_mode_data *data) { return __scsi_mode_sense(SRpnt, dbd, modepage, buffer, len, SD_TIMEOUT, SD_MAX_RETRIES, data); } /* * read write protect setting, if possible - called only in sd_revalidate_disk() * called with buffer of length 512 */ static void sd_read_write_protect_flag(struct scsi_disk *sdkp, char *diskname, struct scsi_request *SRpnt, unsigned char *buffer) { int res; struct scsi_mode_data data; set_disk_ro(sdkp->disk, 0); if (sdkp->device->skip_ms_page_3f) { printk(KERN_NOTICE "%s: assuming Write Enabled\n", diskname); return; } if (sdkp->device->use_192_bytes_for_3f) { res = sd_do_mode_sense(SRpnt, 0, 0x3F, buffer, 192, &data); } else { /* * First attempt: ask for all pages (0x3F), but only 4 bytes. * We have to start carefully: some devices hang if we ask * for more than is available. */ res = sd_do_mode_sense(SRpnt, 0, 0x3F, buffer, 4, &data); /* * Second attempt: ask for page 0 When only page 0 is * implemented, a request for page 3F may return Sense Key * 5: Illegal Request, Sense Code 24: Invalid field in * CDB. */ if (!scsi_status_is_good(res)) res = sd_do_mode_sense(SRpnt, 0, 0, buffer, 4, &data); /* * Third attempt: ask 255 bytes, as we did earlier. */ if (!scsi_status_is_good(res)) res = sd_do_mode_sense(SRpnt, 0, 0x3F, buffer, 255, &data); } if (!scsi_status_is_good(res)) { printk(KERN_WARNING "%s: test WP failed, assume Write Enabled\n", diskname); } else { sdkp->write_prot = ((data.device_specific & 0x80) != 0); set_disk_ro(sdkp->disk, sdkp->write_prot); printk(KERN_NOTICE "%s: Write Protect is %s\n", diskname, sdkp->write_prot ? "on" : "off"); printk(KERN_DEBUG "%s: Mode Sense: %02x %02x %02x %02x\n", diskname, buffer[0], buffer[1], buffer[2], buffer[3]); } } /* * sd_read_cache_type - called only from sd_revalidate_disk() * called with buffer of length 512 */ static void sd_read_cache_type(struct scsi_disk *sdkp, char *diskname, struct scsi_request *SRpnt, unsigned char *buffer) { int len = 0, res; int dbd; int modepage; struct scsi_mode_data data; struct scsi_sense_hdr sshdr; if (sdkp->device->skip_ms_page_8) goto defaults; if (sdkp->device->type == TYPE_RBC) { modepage = 6; dbd = 8; } else { modepage = 8; dbd = 0; } /* cautiously ask */ res = sd_do_mode_sense(SRpnt, dbd, modepage, buffer, 4, &data); if (!scsi_status_is_good(res)) goto bad_sense; /* that went OK, now ask for the proper length */ len = data.length; /* * We're only interested in the first three bytes, actually. * But the data cache page is defined for the first 20. */ if (len < 3) goto bad_sense; if (len > 20) len = 20; /* Take headers and block descriptors into account */ len += data.header_length + data.block_descriptor_length; /* Get the data */ res = sd_do_mode_sense(SRpnt, dbd, modepage, buffer, len, &data); if (scsi_status_is_good(res)) { const char *types[] = { "write through", "none", "write back", "write back, no read (daft)" }; int ct = 0; int offset = data.header_length + data.block_descriptor_length; if ((buffer[offset] & 0x3f) != modepage) { printk(KERN_ERR "%s: got wrong page\n", diskname); goto defaults; } if (modepage == 8) { sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0); sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0); } else { sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0); sdkp->RCD = 0; } ct = sdkp->RCD + 2*sdkp->WCE; printk(KERN_NOTICE "SCSI device %s: drive cache: %s\n", diskname, types[ct]); return; } bad_sense: if (scsi_request_normalize_sense(SRpnt, &sshdr) && sshdr.sense_key == ILLEGAL_REQUEST && sshdr.asc == 0x24 && sshdr.ascq == 0x0) printk(KERN_NOTICE "%s: cache data unavailable\n", diskname); /* Invalid field in CDB */ else printk(KERN_ERR "%s: asking for cache data failed\n", diskname); defaults: printk(KERN_ERR "%s: assuming drive cache: write through\n", diskname); sdkp->WCE = 0; sdkp->RCD = 0; } /** * sd_revalidate_disk - called the first time a new disk is seen, * performs disk spin up, read_capacity, etc. * @disk: struct gendisk we care about **/ static int sd_revalidate_disk(struct gendisk *disk) { struct scsi_disk *sdkp = scsi_disk(disk); struct scsi_device *sdp = sdkp->device; struct scsi_request *sreq; unsigned char *buffer; SCSI_LOG_HLQUEUE(3, printk("sd_revalidate_disk: disk=%s\n", disk->disk_name)); /* * If the device is offline, don't try and read capacity or any * of the other niceties. */ if (!scsi_device_online(sdp)) goto out; sreq = scsi_allocate_request(sdp, GFP_KERNEL); if (!sreq) { printk(KERN_WARNING "(sd_revalidate_disk:) Request allocation " "failure.\n"); goto out; } buffer = kmalloc(512, GFP_KERNEL | __GFP_DMA); if (!buffer) { printk(KERN_WARNING "(sd_revalidate_disk:) Memory allocation " "failure.\n"); goto out_release_request; } /* defaults, until the device tells us otherwise */ sdp->sector_size = 512; sdkp->capacity = 0; sdkp->media_present = 1; sdkp->write_prot = 0; sdkp->WCE = 0; sdkp->RCD = 0; sd_spinup_disk(sdkp, disk->disk_name, sreq, buffer); /* * Without media there is no reason to ask; moreover, some devices * react badly if we do. */ if (sdkp->media_present) { sd_read_capacity(sdkp, disk->disk_name, sreq, buffer); if (sdp->removable) sd_read_write_protect_flag(sdkp, disk->disk_name, sreq, buffer); sd_read_cache_type(sdkp, disk->disk_name, sreq, buffer); } set_capacity(disk, sdkp->capacity); kfree(buffer); out_release_request: scsi_release_request(sreq); out: return 0; } /** * sd_probe - 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. * @dev: pointer to 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. * * Assume sd_attach is not re-entrant (for time being) * Also think about sd_attach() and sd_remove() running coincidentally. **/ static int sd_probe(struct device *dev) { struct scsi_device *sdp = to_scsi_device(dev); struct scsi_disk *sdkp; struct gendisk *gd; u32 index; int error; error = -ENODEV; if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC) goto out; SCSI_LOG_HLQUEUE(3, printk("sd_attach: scsi device: <%d,%d,%d,%d>\n", sdp->host->host_no, sdp->channel, sdp->id, sdp->lun)); error = -ENOMEM; sdkp = kmalloc(sizeof(*sdkp), GFP_KERNEL); if (!sdkp) goto out; memset (sdkp, 0, sizeof(*sdkp)); kref_init(&sdkp->kref); gd = alloc_disk(16); if (!gd) goto out_free; if (!idr_pre_get(&sd_index_idr, GFP_KERNEL)) goto out_put; spin_lock(&sd_index_lock); error = idr_get_new(&sd_index_idr, NULL, &index); spin_unlock(&sd_index_lock); if (index >= SD_MAX_DISKS) error = -EBUSY; if (error) goto out_put; sdkp->device = sdp; sdkp->driver = &sd_template; sdkp->disk = gd; sdkp->index = index; sdkp->openers = 0; if (!sdp->timeout) { if (sdp->type != TYPE_MOD) sdp->timeout = SD_TIMEOUT; else sdp->timeout = SD_MOD_TIMEOUT; } gd->major = sd_major((index & 0xf0) >> 4); gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00); gd->minors = 16; gd->fops = &sd_fops; if (index < 26) { sprintf(gd->disk_name, "sd%c", 'a' + index % 26); } else if (index < (26 + 1) * 26) { sprintf(gd->disk_name, "sd%c%c", 'a' + index / 26 - 1,'a' + index % 26); } else { const unsigned int m1 = (index / 26 - 1) / 26 - 1; const unsigned int m2 = (index / 26 - 1) % 26; const unsigned int m3 = index % 26; sprintf(gd->disk_name, "sd%c%c%c", 'a' + m1, 'a' + m2, 'a' + m3); } strcpy(gd->devfs_name, sdp->devfs_name); gd->private_data = &sdkp->driver; sd_revalidate_disk(gd); gd->driverfs_dev = &sdp->sdev_gendev; gd->flags = GENHD_FL_DRIVERFS; if (sdp->removable) gd->flags |= GENHD_FL_REMOVABLE; gd->queue = sdkp->device->request_queue; dev_set_drvdata(dev, sdkp); add_disk(gd); printk(KERN_NOTICE "Attached scsi %sdisk %s at scsi%d, channel %d, " "id %d, lun %d\n", sdp->removable ? "removable " : "", gd->disk_name, sdp->host->host_no, sdp->channel, sdp->id, sdp->lun); return 0; out_put: put_disk(gd); out_free: kfree(sdkp); out: return error; } /** * sd_remove - called whenever a scsi disk (previously recognized by * sd_probe) 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_probe(). * This function is not called when the built-in sd driver is "exit-ed". **/ static int sd_remove(struct device *dev) { struct scsi_disk *sdkp = dev_get_drvdata(dev); del_gendisk(sdkp->disk); sd_shutdown(dev); down(&sd_ref_sem); kref_put(&sdkp->kref, scsi_disk_release); up(&sd_ref_sem); return 0; } /** * scsi_disk_release - Called to free the scsi_disk structure * @kref: pointer to embedded kref * * sd_ref_sem must be held entering this routine. Because it is * called on last put, you should always use the scsi_disk_get() * scsi_disk_put() helpers which manipulate the semaphore directly * and never do a direct kref_put(). **/ static void scsi_disk_release(struct kref *kref) { struct scsi_disk *sdkp = to_scsi_disk(kref); struct gendisk *disk = sdkp->disk; spin_lock(&sd_index_lock); idr_remove(&sd_index_idr, sdkp->index); spin_unlock(&sd_index_lock); disk->private_data = NULL; put_disk(disk); kfree(sdkp); } /* * Send a SYNCHRONIZE CACHE instruction down to the device through * the normal SCSI command structure. Wait for the command to * complete. */ static void sd_shutdown(struct device *dev) { struct scsi_device *sdp = to_scsi_device(dev); struct scsi_disk *sdkp = dev_get_drvdata(dev); if (!sdkp) return; /* this can happen */ if (!sdkp->WCE) return; printk(KERN_NOTICE "Synchronizing SCSI cache for disk %s: \n", sdkp->disk->disk_name); sd_sync_cache(sdp); } /** * 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 majors = 0, i; SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n")); for (i = 0; i < SD_MAJORS; i++) if (register_blkdev(sd_major(i), "sd") == 0) majors++; if (!majors) return -ENODEV; return scsi_register_driver(&sd_template.gendrv); } /** * 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 i; SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n")); scsi_unregister_driver(&sd_template.gendrv); for (i = 0; i < SD_MAJORS; i++) unregister_blkdev(sd_major(i), "sd"); } MODULE_LICENSE("GPL"); MODULE_AUTHOR("Eric Youngdale"); MODULE_DESCRIPTION("SCSI disk (sd) driver"); module_init(init_sd); module_exit(exit_sd);