On Saturday 06 December 2008, Pete Zaitcev wrote:> On Wed, 03 Dec 2008 09:09:00 -0600, James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:> > > git log tells me ide-scsi has been updated quite a bit recently, but it> > mostly looks to be fallout around the drivers/ide churn. Can we get ide> > maintainer's buy in for this (I think they've been maintaining ide-tape> > and ide-cd in preference to ide-scsi)?> > They must be bonkers to do it. I fixed a couple of bugs in ide-tape> and it was one of the worst drivers I worked on, ever (worse than> floppy.c, I kid you not). It definitely must die before ide-scsi.> Fortunately, I solved this issue by hooking my tape to USB bridge,> or else I'd be up in arms and wanting Tomo's blood.
Pete, I don't mean any disrespect or to deny your credit for your pastcontributions but it must have been "quite a some" time ago since you werelast working on ide-tape. ;-)
[ To be sure I checked both Linus' tree (which goes back to Apr 2005, 2.6.12 timeframe) and Thomas' historical git tree (Feb 2002 / 2.4.1) -- I don't see any IDE changes from you there. ]
In the recent years Borislav and me put substantial work into puttingide-tape into a sane state (mainly as a by-product of working on genericATAPI support) and although many improvements are still possible (BTWpatches are always warmly welcomed) it doesn't contain any horrors likeidescsi_eh_abort() / idescsi_eh_reset() in ide-scsi. Moreover ide-tapeis of much less complexity than SCSI st driver (afterall ide-tape.c isnow almost half of the size / lines of code of st.c).
See for yourself, ide-tape.c from Linus' tree:
/* * IDE ATAPI streaming tape driver. * * Copyright (C) 1995-1999 Gadi Oxman <gadio@xxxxxxxxxxxxxxxx> * Copyright (C) 2003-2005 Bartlomiej Zolnierkiewicz * * This driver was constructed as a student project in the software laboratory * of the faculty of electrical engineering in the Technion - Israel's * Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David. * * It is hereby placed under the terms of the GNU general public license. * (See linux/COPYING). * * For a historical changelog see * Documentation/ide/ChangeLog.ide-tape.1995-2002 */
#define DRV_NAME "ide-tape"
#define IDETAPE_VERSION "1.20"
#include <linux/module.h>#include <linux/types.h>#include <linux/string.h>#include <linux/kernel.h>#include <linux/delay.h>#include <linux/timer.h>#include <linux/mm.h>#include <linux/interrupt.h>#include <linux/jiffies.h>#include <linux/major.h>#include <linux/errno.h>#include <linux/genhd.h>#include <linux/slab.h>#include <linux/pci.h>#include <linux/ide.h>#include <linux/smp_lock.h>#include <linux/completion.h>#include <linux/bitops.h>#include <linux/mutex.h>#include <scsi/scsi.h>
#include <asm/byteorder.h>#include <linux/irq.h>#include <linux/uaccess.h>#include <linux/io.h>#include <asm/unaligned.h>#include <linux/mtio.h>
enum { /* output errors only */ DBG_ERR = (1 << 0), /* output all sense key/asc */ DBG_SENSE = (1 << 1), /* info regarding all chrdev-related procedures */ DBG_CHRDEV = (1 << 2), /* all remaining procedures */ DBG_PROCS = (1 << 3),};
/* define to see debug info */#define IDETAPE_DEBUG_LOG 0
#if IDETAPE_DEBUG_LOG#define debug_log(lvl, fmt, args...) \{ \ if (tape->debug_mask & lvl) \ printk(KERN_INFO "ide-tape: " fmt, ## args); \}#else#define debug_log(lvl, fmt, args...) do {} while (0)#endif
/**************************** Tunable parameters *****************************//* * After each failed packet command we issue a request sense command and retry * the packet command IDETAPE_MAX_PC_RETRIES times. * * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries. */#define IDETAPE_MAX_PC_RETRIES 3
/* * The following parameter is used to select the point in the internal tape fifo * in which we will start to refill the buffer. Decreasing the following * parameter will improve the system's latency and interactive response, while * using a high value might improve system throughput. */#define IDETAPE_FIFO_THRESHOLD 2
/* * DSC polling parameters. * * Polling for DSC (a single bit in the status register) is a very important * function in ide-tape. There are two cases in which we poll for DSC: * * 1. Before a read/write packet command, to ensure that we can transfer data * from/to the tape's data buffers, without causing an actual media access. * In case the tape is not ready yet, we take out our request from the device * request queue, so that ide.c could service requests from the other device * on the same interface in the meantime. * * 2. After the successful initialization of a "media access packet command", * which is a command that can take a long time to complete (the interval can * range from several seconds to even an hour). Again, we postpone our request * in the middle to free the bus for the other device. The polling frequency * here should be lower than the read/write frequency since those media access * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min). * * We also set a timeout for the timer, in case something goes wrong. The * timeout should be longer then the maximum execution time of a tape operation. */
/* DSC timings. */#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */
/*************************** End of tunable parameters ***********************/
/* tape directions */enum { IDETAPE_DIR_NONE = (1 << 0), IDETAPE_DIR_READ = (1 << 1), IDETAPE_DIR_WRITE = (1 << 2),};
struct idetape_bh { u32 b_size; atomic_t b_count; struct idetape_bh *b_reqnext; char *b_data;};
/* Tape door status */#define DOOR_UNLOCKED 0#define DOOR_LOCKED 1#define DOOR_EXPLICITLY_LOCKED 2
/* Some defines for the SPACE command */#define IDETAPE_SPACE_OVER_FILEMARK 1#define IDETAPE_SPACE_TO_EOD 3
/* Some defines for the LOAD UNLOAD command */#define IDETAPE_LU_LOAD_MASK 1#define IDETAPE_LU_RETENSION_MASK 2#define IDETAPE_LU_EOT_MASK 4
/* Error codes returned in rq->errors to the higher part of the driver. */#define IDETAPE_ERROR_GENERAL 101#define IDETAPE_ERROR_FILEMARK 102#define IDETAPE_ERROR_EOD 103
/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */#define IDETAPE_BLOCK_DESCRIPTOR 0#define IDETAPE_CAPABILITIES_PAGE 0x2a
/* * Most of our global data which we need to save even as we leave the driver due * to an interrupt or a timer event is stored in the struct defined below. */typedef struct ide_tape_obj { ide_drive_t *drive; ide_driver_t *driver; struct gendisk *disk; struct kref kref;
/* * failed_pc points to the last failed packet command, or contains * NULL if we do not need to retry any packet command. This is * required since an additional packet command is needed before the * retry, to get detailed information on what went wrong. */ /* Last failed packet command */ struct ide_atapi_pc *failed_pc; /* used by REQ_IDETAPE_{READ,WRITE} requests */ struct ide_atapi_pc queued_pc;
/* * DSC polling variables. * * While polling for DSC we use postponed_rq to postpone the current * request so that ide.c will be able to service pending requests on the * other device. Note that at most we will have only one DSC (usually * data transfer) request in the device request queue. */ struct request *postponed_rq; /* The time in which we started polling for DSC */ unsigned long dsc_polling_start; /* Timer used to poll for dsc */ struct timer_list dsc_timer; /* Read/Write dsc polling frequency */ unsigned long best_dsc_rw_freq; unsigned long dsc_poll_freq; unsigned long dsc_timeout;
/* Read position information */ u8 partition; /* Current block */ unsigned int first_frame;
/* Last error information */ u8 sense_key, asc, ascq;
/* Character device operation */ unsigned int minor; /* device name */ char name[4]; /* Current character device data transfer direction */ u8 chrdev_dir;
/* tape block size, usually 512 or 1024 bytes */ unsigned short blk_size; int user_bs_factor;
/* Copy of the tape's Capabilities and Mechanical Page */ u8 caps[20];
/* * Active data transfer request parameters. * * At most, there is only one ide-tape originated data transfer request * in the device request queue. This allows ide.c to easily service * requests from the other device when we postpone our active request. */
/* Data buffer size chosen based on the tape's recommendation */ int buffer_size; /* merge buffer */ struct idetape_bh *merge_bh; /* size of the merge buffer */ int merge_bh_size; /* pointer to current buffer head within the merge buffer */ struct idetape_bh *bh; char *b_data; int b_count;
int pages_per_buffer; /* Wasted space in each stage */ int excess_bh_size;
/* protects the ide-tape queue */ spinlock_t lock;
/* Measures average tape speed */ unsigned long avg_time; int avg_size; int avg_speed;
/* the door is currently locked */ int door_locked; /* the tape hardware is write protected */ char drv_write_prot; /* the tape is write protected (hardware or opened as read-only) */ char write_prot;
u32 debug_mask;} idetape_tape_t;
static DEFINE_MUTEX(idetape_ref_mutex);
static struct class *idetape_sysfs_class;
static void ide_tape_release(struct kref *);
static struct ide_tape_obj *ide_tape_get(struct gendisk *disk){ struct ide_tape_obj *tape = NULL;
mutex_lock(&idetape_ref_mutex); tape = ide_drv_g(disk, ide_tape_obj); if (tape) { if (ide_device_get(tape->drive)) tape = NULL; else kref_get(&tape->kref); } mutex_unlock(&idetape_ref_mutex); return tape;}
static void ide_tape_put(struct ide_tape_obj *tape){ ide_drive_t *drive = tape->drive;
mutex_lock(&idetape_ref_mutex); kref_put(&tape->kref, ide_tape_release); ide_device_put(drive); mutex_unlock(&idetape_ref_mutex);}
/* * The variables below are used for the character device interface. Additional * state variables are defined in our ide_drive_t structure. */static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i){ struct ide_tape_obj *tape = NULL;
mutex_lock(&idetape_ref_mutex); tape = idetape_devs[i]; if (tape) kref_get(&tape->kref); mutex_unlock(&idetape_ref_mutex); return tape;}
static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, unsigned int bcount){ struct idetape_bh *bh = pc->bh; int count;
while (bcount) { if (bh == NULL) { printk(KERN_ERR "ide-tape: bh == NULL in " "idetape_input_buffers\n"); ide_pad_transfer(drive, 0, bcount); return; } count = min( (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount); drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data + atomic_read(&bh->b_count), count); bcount -= count; atomic_add(count, &bh->b_count); if (atomic_read(&bh->b_count) == bh->b_size) { bh = bh->b_reqnext; if (bh) atomic_set(&bh->b_count, 0); } } pc->bh = bh;}
static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, unsigned int bcount){ struct idetape_bh *bh = pc->bh; int count;
while (bcount) { if (bh == NULL) { printk(KERN_ERR "ide-tape: bh == NULL in %s\n", __func__); return; } count = min((unsigned int)pc->b_count, (unsigned int)bcount); drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); bcount -= count; pc->b_data += count; pc->b_count -= count; if (!pc->b_count) { bh = bh->b_reqnext; pc->bh = bh; if (bh) { pc->b_data = bh->b_data; pc->b_count = atomic_read(&bh->b_count); } } }}
static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc){ struct idetape_bh *bh = pc->bh; int count; unsigned int bcount = pc->xferred;
if (pc->flags & PC_FLAG_WRITING) return; while (bcount) { if (bh == NULL) { printk(KERN_ERR "ide-tape: bh == NULL in %s\n", __func__); return; } count = min((unsigned int)bh->b_size, (unsigned int)bcount); atomic_set(&bh->b_count, count); if (atomic_read(&bh->b_count) == bh->b_size) bh = bh->b_reqnext; bcount -= count; } pc->bh = bh;}
/* * called on each failed packet command retry to analyze the request sense. We * currently do not utilize this information. */static void idetape_analyze_error(ide_drive_t *drive, u8 *sense){ idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc *pc = tape->failed_pc;
tape->sense_key = sense[2] & 0xF; tape->asc = sense[12]; tape->ascq = sense[13];
debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", pc->c[0], tape->sense_key, tape->asc, tape->ascq);
/* Correct pc->xferred by asking the tape. */ if (pc->flags & PC_FLAG_DMA_ERROR) { pc->xferred = pc->req_xfer - tape->blk_size * get_unaligned_be32(&sense[3]); idetape_update_buffers(drive, pc); }
/* * If error was the result of a zero-length read or write command, * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. */ if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) /* length == 0 */ && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { if (tape->sense_key == 5) { /* don't report an error, everything's ok */ pc->error = 0; /* don't retry read/write */ pc->flags |= PC_FLAG_ABORT; } } if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { pc->error = IDETAPE_ERROR_FILEMARK; pc->flags |= PC_FLAG_ABORT; } if (pc->c[0] == WRITE_6) { if ((sense[2] & 0x40) || (tape->sense_key == 0xd && tape->asc == 0x0 && tape->ascq == 0x2)) { pc->error = IDETAPE_ERROR_EOD; pc->flags |= PC_FLAG_ABORT; } } if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { if (tape->sense_key == 8) { pc->error = IDETAPE_ERROR_EOD; pc->flags |= PC_FLAG_ABORT; } if (!(pc->flags & PC_FLAG_ABORT) && pc->xferred) pc->retries = IDETAPE_MAX_PC_RETRIES + 1; }}
/* Free data buffers completely. */static void ide_tape_kfree_buffer(idetape_tape_t *tape){ struct idetape_bh *prev_bh, *bh = tape->merge_bh;
while (bh) { u32 size = bh->b_size;
while (size) { unsigned int order = fls(size >> PAGE_SHIFT)-1;
if (bh->b_data) free_pages((unsigned long)bh->b_data, order);
size &= (order-1); bh->b_data += (1 << order) * PAGE_SIZE; } prev_bh = bh; bh = bh->b_reqnext; kfree(prev_bh); }}
static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects){ struct request *rq = HWGROUP(drive)->rq; idetape_tape_t *tape = drive->driver_data; unsigned long flags; int error;
debug_log(DBG_PROCS, "Enter %s\n", __func__);
switch (uptodate) { case 0: error = IDETAPE_ERROR_GENERAL; break; case 1: error = 0; break; default: error = uptodate; } rq->errors = error; if (error) tape->failed_pc = NULL;
if (!blk_special_request(rq)) { ide_end_request(drive, uptodate, nr_sects); return 0; }
spin_lock_irqsave(&tape->lock, flags);
ide_end_drive_cmd(drive, 0, 0);
spin_unlock_irqrestore(&tape->lock, flags); return 0;}
static void ide_tape_handle_dsc(ide_drive_t *);
static void ide_tape_callback(ide_drive_t *drive, int dsc){ idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc *pc = drive->pc; int uptodate = pc->error ? 0 : 1;
debug_log(DBG_PROCS, "Enter %s\n", __func__);
if (dsc) ide_tape_handle_dsc(drive);
if (tape->failed_pc == pc) tape->failed_pc = NULL;
if (pc->c[0] == REQUEST_SENSE) { if (uptodate) idetape_analyze_error(drive, pc->buf); else printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " "itself - Aborting request!\n"); } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { struct request *rq = drive->hwif->hwgroup->rq; int blocks = pc->xferred / tape->blk_size;
tape->avg_size += blocks * tape->blk_size;
if (time_after_eq(jiffies, tape->avg_time + HZ)) { tape->avg_speed = tape->avg_size * HZ / (jiffies - tape->avg_time) / 1024; tape->avg_size = 0; tape->avg_time = jiffies; }
tape->first_frame += blocks; rq->current_nr_sectors -= blocks;
if (pc->error) uptodate = pc->error; } else if (pc->c[0] == READ_POSITION && uptodate) { u8 *readpos = pc->buf;
debug_log(DBG_SENSE, "BOP - %s\n", (readpos[0] & 0x80) ? "Yes" : "No"); debug_log(DBG_SENSE, "EOP - %s\n", (readpos[0] & 0x40) ? "Yes" : "No");
if (readpos[0] & 0x4) { printk(KERN_INFO "ide-tape: Block location is unknown" "to the tape\n"); clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); uptodate = 0; } else { debug_log(DBG_SENSE, "Block Location - %u\n", be32_to_cpup((__be32 *)&readpos[4]));
tape->partition = readpos[1]; tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]); set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); } }
idetape_end_request(drive, uptodate, 0);}
/* * Postpone the current request so that ide.c will be able to service requests * from another device on the same hwgroup while we are polling for DSC. */static void idetape_postpone_request(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data;
debug_log(DBG_PROCS, "Enter %s\n", __func__);
tape->postponed_rq = HWGROUP(drive)->rq; ide_stall_queue(drive, tape->dsc_poll_freq);}
static void ide_tape_handle_dsc(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data;
/* Media access command */ tape->dsc_polling_start = jiffies; tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; /* Allow ide.c to handle other requests */ idetape_postpone_request(drive);}
static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, unsigned int bcount, int write){ if (write) idetape_output_buffers(drive, pc, bcount); else idetape_input_buffers(drive, pc, bcount);
return bcount;}
/* * Packet Command Interface * * The current Packet Command is available in drive->pc, and will not change * until we finish handling it. Each packet command is associated with a * callback function that will be called when the command is finished. * * The handling will be done in three stages: * * 1. idetape_issue_pc will send the packet command to the drive, and will set * the interrupt handler to ide_pc_intr. * * 2. On each interrupt, ide_pc_intr will be called. This step will be * repeated until the device signals us that no more interrupts will be issued. * * 3. ATAPI Tape media access commands have immediate status with a delayed * process. In case of a successful initiation of a media access packet command, * the DSC bit will be set when the actual execution of the command is finished. * Since the tape drive will not issue an interrupt, we have to poll for this * event. In this case, we define the request as "low priority request" by * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and * exit the driver. * * ide.c will then give higher priority to requests which originate from the * other device, until will change rq_status to RQ_ACTIVE. * * 4. When the packet command is finished, it will be checked for errors. * * 5. In case an error was found, we queue a request sense packet command in * front of the request queue and retry the operation up to * IDETAPE_MAX_PC_RETRIES times. * * 6. In case no error was found, or we decided to give up and not to retry * again, the callback function will be called and then we will handle the next * request. */
static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, struct ide_atapi_pc *pc){ idetape_tape_t *tape = drive->driver_data;
if (drive->pc->c[0] == REQUEST_SENSE && pc->c[0] == REQUEST_SENSE) { printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " "Two request sense in serial were issued\n"); }
if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) tape->failed_pc = pc;
/* Set the current packet command */ drive->pc = pc;
if (pc->retries > IDETAPE_MAX_PC_RETRIES || (pc->flags & PC_FLAG_ABORT)) { /* * We will "abort" retrying a packet command in case legitimate * error code was received (crossing a filemark, or end of the * media, for example). */ if (!(pc->flags & PC_FLAG_ABORT)) { if (!(pc->c[0] == TEST_UNIT_READY && tape->sense_key == 2 && tape->asc == 4 && (tape->ascq == 1 || tape->ascq == 8))) { printk(KERN_ERR "ide-tape: %s: I/O error, " "pc = %2x, key = %2x, " "asc = %2x, ascq = %2x\n", tape->name, pc->c[0], tape->sense_key, tape->asc, tape->ascq); } /* Giving up */ pc->error = IDETAPE_ERROR_GENERAL; } tape->failed_pc = NULL; drive->pc_callback(drive, 0); return ide_stopped; } debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
pc->retries++;
return ide_issue_pc(drive, WAIT_TAPE_CMD, NULL);}
/* A mode sense command is used to "sense" tape parameters. */static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code){ ide_init_pc(pc); pc->c[0] = MODE_SENSE; if (page_code != IDETAPE_BLOCK_DESCRIPTOR) /* DBD = 1 - Don't return block descriptors */ pc->c[1] = 8; pc->c[2] = page_code; /* * Changed pc->c[3] to 0 (255 will at best return unused info). * * For SCSI this byte is defined as subpage instead of high byte * of length and some IDE drives seem to interpret it this way * and return an error when 255 is used. */ pc->c[3] = 0; /* We will just discard data in that case */ pc->c[4] = 255; if (page_code == IDETAPE_BLOCK_DESCRIPTOR) pc->req_xfer = 12; else if (page_code == IDETAPE_CAPABILITIES_PAGE) pc->req_xfer = 24; else pc->req_xfer = 50;}
static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive){ ide_hwif_t *hwif = drive->hwif; idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc *pc = drive->pc; u8 stat;
stat = hwif->tp_ops->read_status(hwif);
if (stat & ATA_DSC) { if (stat & ATA_ERR) { /* Error detected */ if (pc->c[0] != TEST_UNIT_READY) printk(KERN_ERR "ide-tape: %s: I/O error, ", tape->name); /* Retry operation */ ide_retry_pc(drive, tape->disk); return ide_stopped; } pc->error = 0; } else { pc->error = IDETAPE_ERROR_GENERAL; tape->failed_pc = NULL; } drive->pc_callback(drive, 0); return ide_stopped;}
static void ide_tape_create_rw_cmd(idetape_tape_t *tape, struct ide_atapi_pc *pc, struct request *rq, u8 opcode){ struct idetape_bh *bh = (struct idetape_bh *)rq->special; unsigned int length = rq->current_nr_sectors;
ide_init_pc(pc); put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); pc->c[1] = 1; pc->bh = bh; pc->buf = NULL; pc->buf_size = length * tape->blk_size; pc->req_xfer = pc->buf_size; if (pc->req_xfer == tape->buffer_size) pc->flags |= PC_FLAG_DMA_OK;
if (opcode == READ_6) { pc->c[0] = READ_6; atomic_set(&bh->b_count, 0); } else if (opcode == WRITE_6) { pc->c[0] = WRITE_6; pc->flags |= PC_FLAG_WRITING; pc->b_data = bh->b_data; pc->b_count = atomic_read(&bh->b_count); }
memcpy(rq->cmd, pc->c, 12);}
static ide_startstop_t idetape_do_request(ide_drive_t *drive, struct request *rq, sector_t block){ ide_hwif_t *hwif = drive->hwif; idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc *pc = NULL; struct request *postponed_rq = tape->postponed_rq; u8 stat;
debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," " current_nr_sectors: %u\n", (unsigned long long)rq->sector, rq->nr_sectors, rq->current_nr_sectors);
if (!blk_special_request(rq)) { /* We do not support buffer cache originated requests. */ printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " "request queue (%d)\n", drive->name, rq->cmd_type); ide_end_request(drive, 0, 0); return ide_stopped; }
/* Retry a failed packet command */ if (tape->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { pc = tape->failed_pc; goto out; }
if (postponed_rq != NULL) if (rq != postponed_rq) { printk(KERN_ERR "ide-tape: ide-tape.c bug - " "Two DSC requests were queued\n"); idetape_end_request(drive, 0, 0); return ide_stopped; }
tape->postponed_rq = NULL;
/* * If the tape is still busy, postpone our request and service * the other device meanwhile. */ stat = hwif->tp_ops->read_status(hwif);
if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 && (rq->cmd[13] & REQ_IDETAPE_PC2) == 0) set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
if (drive->dev_flags & IDE_DFLAG_POST_RESET) { set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); drive->dev_flags &= ~IDE_DFLAG_POST_RESET; }
if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && (stat & ATA_DSC) == 0) { if (postponed_rq == NULL) { tape->dsc_polling_start = jiffies; tape->dsc_poll_freq = tape->best_dsc_rw_freq; tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; } else if (time_after(jiffies, tape->dsc_timeout)) { printk(KERN_ERR "ide-tape: %s: DSC timeout\n", tape->name); if (rq->cmd[13] & REQ_IDETAPE_PC2) { idetape_media_access_finished(drive); return ide_stopped; } else { return ide_do_reset(drive); } } else if (time_after(jiffies, tape->dsc_polling_start + IDETAPE_DSC_MA_THRESHOLD)) tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; idetape_postpone_request(drive); return ide_stopped; } if (rq->cmd[13] & REQ_IDETAPE_READ) { pc = &tape->queued_pc; ide_tape_create_rw_cmd(tape, pc, rq, READ_6); goto out; } if (rq->cmd[13] & REQ_IDETAPE_WRITE) { pc = &tape->queued_pc; ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); goto out; } if (rq->cmd[13] & REQ_IDETAPE_PC1) { pc = (struct ide_atapi_pc *) rq->buffer; rq->cmd[13] &= ~(REQ_IDETAPE_PC1); rq->cmd[13] |= REQ_IDETAPE_PC2; goto out; } if (rq->cmd[13] & REQ_IDETAPE_PC2) { idetape_media_access_finished(drive); return ide_stopped; } BUG();
out: return idetape_issue_pc(drive, pc);}
/* * The function below uses __get_free_pages to allocate a data buffer of size * tape->buffer_size (or a bit more). We attempt to combine sequential pages as * much as possible. * * It returns a pointer to the newly allocated buffer, or NULL in case of * failure. */static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, int full, int clear){ struct idetape_bh *prev_bh, *bh, *merge_bh; int pages = tape->pages_per_buffer; unsigned int order, b_allocd; char *b_data = NULL;
merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); bh = merge_bh; if (bh == NULL) goto abort;
order = fls(pages) - 1; bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); if (!bh->b_data) goto abort; b_allocd = (1 << order) * PAGE_SIZE; pages &= (order-1);
if (clear) memset(bh->b_data, 0, b_allocd); bh->b_reqnext = NULL; bh->b_size = b_allocd; atomic_set(&bh->b_count, full ? bh->b_size : 0);
while (pages) { order = fls(pages) - 1; b_data = (char *) __get_free_pages(GFP_KERNEL, order); if (!b_data) goto abort; b_allocd = (1 << order) * PAGE_SIZE;
if (clear) memset(b_data, 0, b_allocd);
/* newly allocated page frames below buffer header or ...*/ if (bh->b_data == b_data + b_allocd) { bh->b_size += b_allocd; bh->b_data -= b_allocd; if (full) atomic_add(b_allocd, &bh->b_count); continue; } /* they are above the header */ if (b_data == bh->b_data + bh->b_size) { bh->b_size += b_allocd; if (full) atomic_add(b_allocd, &bh->b_count); continue; } prev_bh = bh; bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); if (!bh) { free_pages((unsigned long) b_data, order); goto abort; } bh->b_reqnext = NULL; bh->b_data = b_data; bh->b_size = b_allocd; atomic_set(&bh->b_count, full ? bh->b_size : 0); prev_bh->b_reqnext = bh;
pages &= (order-1); }
bh->b_size -= tape->excess_bh_size; if (full) atomic_sub(tape->excess_bh_size, &bh->b_count); return merge_bh;abort: ide_tape_kfree_buffer(tape); return NULL;}
static int idetape_copy_stage_from_user(idetape_tape_t *tape, const char __user *buf, int n){ struct idetape_bh *bh = tape->bh; int count; int ret = 0;
while (n) { if (bh == NULL) { printk(KERN_ERR "ide-tape: bh == NULL in %s\n", __func__); return 1; } count = min((unsigned int) (bh->b_size - atomic_read(&bh->b_count)), (unsigned int)n); if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, count)) ret = 1; n -= count; atomic_add(count, &bh->b_count); buf += count; if (atomic_read(&bh->b_count) == bh->b_size) { bh = bh->b_reqnext; if (bh) atomic_set(&bh->b_count, 0); } } tape->bh = bh; return ret;}
static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, int n){ struct idetape_bh *bh = tape->bh; int count; int ret = 0;
while (n) { if (bh == NULL) { printk(KERN_ERR "ide-tape: bh == NULL in %s\n", __func__); return 1; } count = min(tape->b_count, n); if (copy_to_user(buf, tape->b_data, count)) ret = 1; n -= count; tape->b_data += count; tape->b_count -= count; buf += count; if (!tape->b_count) { bh = bh->b_reqnext; tape->bh = bh; if (bh) { tape->b_data = bh->b_data; tape->b_count = atomic_read(&bh->b_count); } } } return ret;}
static void idetape_init_merge_buffer(idetape_tape_t *tape){ struct idetape_bh *bh = tape->merge_bh; tape->bh = tape->merge_bh;
if (tape->chrdev_dir == IDETAPE_DIR_WRITE) atomic_set(&bh->b_count, 0); else { tape->b_data = bh->b_data; tape->b_count = atomic_read(&bh->b_count); }}
/* * Write a filemark if write_filemark=1. Flush the device buffers without * writing a filemark otherwise. */static void idetape_create_write_filemark_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc, int write_filemark){ ide_init_pc(pc); pc->c[0] = WRITE_FILEMARKS; pc->c[4] = write_filemark; pc->flags |= PC_FLAG_WAIT_FOR_DSC;}
static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout){ idetape_tape_t *tape = drive->driver_data; struct gendisk *disk = tape->disk; int load_attempted = 0;
/* Wait for the tape to become ready */ set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); timeout += jiffies; while (time_before(jiffies, timeout)) { if (ide_do_test_unit_ready(drive, disk) == 0) return 0; if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) || (tape->asc == 0x3A)) { /* no media */ if (load_attempted) return -ENOMEDIUM; ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); load_attempted = 1; /* not about to be ready */ } else if (!(tape->sense_key == 2 && tape->asc == 4 && (tape->ascq == 1 || tape->ascq == 8))) return -EIO; msleep(100); } return -EIO;}
static int idetape_flush_tape_buffers(ide_drive_t *drive){ struct ide_tape_obj *tape = drive->driver_data; struct ide_atapi_pc pc; int rc;
idetape_create_write_filemark_cmd(drive, &pc, 0); rc = ide_queue_pc_tail(drive, tape->disk, &pc); if (rc) return rc; idetape_wait_ready(drive, 60 * 5 * HZ); return 0;}
static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc){ ide_init_pc(pc); pc->c[0] = READ_POSITION; pc->req_xfer = 20;}
static int idetape_read_position(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc pc; int position;
debug_log(DBG_PROCS, "Enter %s\n", __func__);
idetape_create_read_position_cmd(&pc); if (ide_queue_pc_tail(drive, tape->disk, &pc)) return -1; position = tape->first_frame; return position;}
static void idetape_create_locate_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc, unsigned int block, u8 partition, int skip){ ide_init_pc(pc); pc->c[0] = POSITION_TO_ELEMENT; pc->c[1] = 2; put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); pc->c[8] = partition; pc->flags |= PC_FLAG_WAIT_FOR_DSC;}
static void __ide_tape_discard_merge_buffer(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data;
if (tape->chrdev_dir != IDETAPE_DIR_READ) return;
clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); tape->merge_bh_size = 0; if (tape->merge_bh != NULL) { ide_tape_kfree_buffer(tape); tape->merge_bh = NULL; }
tape->chrdev_dir = IDETAPE_DIR_NONE;}
/* * Position the tape to the requested block using the LOCATE packet command. * A READ POSITION command is then issued to check where we are positioned. Like * all higher level operations, we queue the commands at the tail of the request * queue and wait for their completion. */static int idetape_position_tape(ide_drive_t *drive, unsigned int block, u8 partition, int skip){ idetape_tape_t *tape = drive->driver_data; struct gendisk *disk = tape->disk; int retval; struct ide_atapi_pc pc;
if (tape->chrdev_dir == IDETAPE_DIR_READ) __ide_tape_discard_merge_buffer(drive); idetape_wait_ready(drive, 60 * 5 * HZ); idetape_create_locate_cmd(drive, &pc, block, partition, skip); retval = ide_queue_pc_tail(drive, disk, &pc); if (retval) return (retval);
idetape_create_read_position_cmd(&pc); return ide_queue_pc_tail(drive, disk, &pc);}
static void ide_tape_discard_merge_buffer(ide_drive_t *drive, int restore_position){ idetape_tape_t *tape = drive->driver_data; int seek, position;
__ide_tape_discard_merge_buffer(drive); if (restore_position) { position = idetape_read_position(drive); seek = position > 0 ? position : 0; if (idetape_position_tape(drive, seek, 0, 0)) { printk(KERN_INFO "ide-tape: %s: position_tape failed in" " %s\n", tape->name, __func__); return; } }}
/* * Generate a read/write request for the block device interface and wait for it * to be serviced. */static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, struct idetape_bh *bh){ idetape_tape_t *tape = drive->driver_data; struct request *rq; int ret, errors;
debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
rq = blk_get_request(drive->queue, READ, __GFP_WAIT); rq->cmd_type = REQ_TYPE_SPECIAL; rq->cmd[13] = cmd; rq->rq_disk = tape->disk; rq->special = (void *)bh; rq->sector = tape->first_frame; rq->nr_sectors = blocks; rq->current_nr_sectors = blocks; blk_execute_rq(drive->queue, tape->disk, rq, 0);
errors = rq->errors; ret = tape->blk_size * (blocks - rq->current_nr_sectors); blk_put_request(rq);
if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) return 0;
if (tape->merge_bh) idetape_init_merge_buffer(tape); if (errors == IDETAPE_ERROR_GENERAL) return -EIO; return ret;}
static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc){ ide_init_pc(pc); pc->c[0] = INQUIRY; pc->c[4] = 254; pc->req_xfer = 254;}
static void idetape_create_rewind_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc){ ide_init_pc(pc); pc->c[0] = REZERO_UNIT; pc->flags |= PC_FLAG_WAIT_FOR_DSC;}
static void idetape_create_erase_cmd(struct ide_atapi_pc *pc){ ide_init_pc(pc); pc->c[0] = ERASE; pc->c[1] = 1; pc->flags |= PC_FLAG_WAIT_FOR_DSC;}
static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd){ ide_init_pc(pc); pc->c[0] = SPACE; put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); pc->c[1] = cmd; pc->flags |= PC_FLAG_WAIT_FOR_DSC;}
/* Queue up a character device originated write request. */static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks){ idetape_tape_t *tape = drive->driver_data;
debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_bh);}
static void ide_tape_flush_merge_buffer(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data; int blocks, min; struct idetape_bh *bh;
if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" " but we are not writing.\n"); return; } if (tape->merge_bh_size > tape->buffer_size) { printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); tape->merge_bh_size = tape->buffer_size; } if (tape->merge_bh_size) { blocks = tape->merge_bh_size / tape->blk_size; if (tape->merge_bh_size % tape->blk_size) { unsigned int i;
blocks++; i = tape->blk_size - tape->merge_bh_size % tape->blk_size; bh = tape->bh->b_reqnext; while (bh) { atomic_set(&bh->b_count, 0); bh = bh->b_reqnext; } bh = tape->bh; while (i) { if (bh == NULL) { printk(KERN_INFO "ide-tape: bug," " bh NULL\n"); break; } min = min(i, (unsigned int)(bh->b_size - atomic_read(&bh->b_count))); memset(bh->b_data + atomic_read(&bh->b_count), 0, min); atomic_add(min, &bh->b_count); i -= min; bh = bh->b_reqnext; } } (void) idetape_add_chrdev_write_request(drive, blocks); tape->merge_bh_size = 0; } if (tape->merge_bh != NULL) { ide_tape_kfree_buffer(tape); tape->merge_bh = NULL; } tape->chrdev_dir = IDETAPE_DIR_NONE;}
static int idetape_init_read(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data; int bytes_read;
/* Initialize read operation */ if (tape->chrdev_dir != IDETAPE_DIR_READ) { if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { ide_tape_flush_merge_buffer(drive); idetape_flush_tape_buffers(drive); } if (tape->merge_bh || tape->merge_bh_size) { printk(KERN_ERR "ide-tape: merge_bh_size should be" " 0 now\n"); tape->merge_bh_size = 0; } tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); if (!tape->merge_bh) return -ENOMEM; tape->chrdev_dir = IDETAPE_DIR_READ;
/* * Issue a read 0 command to ensure that DSC handshake is * switched from completion mode to buffer available mode. * No point in issuing this if DSC overlap isn't supported, some * drives (Seagate STT3401A) will return an error. */ if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { bytes_read = idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, 0, tape->merge_bh); if (bytes_read < 0) { ide_tape_kfree_buffer(tape); tape->merge_bh = NULL; tape->chrdev_dir = IDETAPE_DIR_NONE; return bytes_read; } } }
return 0;}
/* called from idetape_chrdev_read() to service a chrdev read request. */static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks){ idetape_tape_t *tape = drive->driver_data;
debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
/* If we are at a filemark, return a read length of 0 */ if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) return 0;
idetape_init_read(drive);
return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, tape->merge_bh);}
static void idetape_pad_zeros(ide_drive_t *drive, int bcount){ idetape_tape_t *tape = drive->driver_data; struct idetape_bh *bh; int blocks;
while (bcount) { unsigned int count;
bh = tape->merge_bh; count = min(tape->buffer_size, bcount); bcount -= count; blocks = count / tape->blk_size; while (count) { atomic_set(&bh->b_count, min(count, (unsigned int)bh->b_size)); memset(bh->b_data, 0, atomic_read(&bh->b_count)); count -= atomic_read(&bh->b_count); bh = bh->b_reqnext; } idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_bh); }}
/* * Rewinds the tape to the Beginning Of the current Partition (BOP). We * currently support only one partition. */static int idetape_rewind_tape(ide_drive_t *drive){ struct ide_tape_obj *tape = drive->driver_data; struct gendisk *disk = tape->disk; int retval; struct ide_atapi_pc pc;
debug_log(DBG_SENSE, "Enter %s\n", __func__);
idetape_create_rewind_cmd(drive, &pc); retval = ide_queue_pc_tail(drive, disk, &pc); if (retval) return retval;
idetape_create_read_position_cmd(&pc); retval = ide_queue_pc_tail(drive, disk, &pc); if (retval) return retval; return 0;}
/* mtio.h compatible commands should be issued to the chrdev interface. */static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, unsigned long arg){ idetape_tape_t *tape = drive->driver_data; void __user *argp = (void __user *)arg;
struct idetape_config { int dsc_rw_frequency; int dsc_media_access_frequency; int nr_stages; } config;
debug_log(DBG_PROCS, "Enter %s\n", __func__);
switch (cmd) { case 0x0340: if (copy_from_user(&config, argp, sizeof(config))) return -EFAULT; tape->best_dsc_rw_freq = config.dsc_rw_frequency; break; case 0x0350: config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; config.nr_stages = 1; if (copy_to_user(argp, &config, sizeof(config))) return -EFAULT; break; default: return -EIO; } return 0;}
static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, int mt_count){ idetape_tape_t *tape = drive->driver_data; struct gendisk *disk = tape->disk; struct ide_atapi_pc pc; int retval, count = 0; int sprev = !!(tape->caps[4] & 0x20);
if (mt_count == 0) return 0; if (MTBSF == mt_op || MTBSFM == mt_op) { if (!sprev) return -EIO; mt_count = -mt_count; }
if (tape->chrdev_dir == IDETAPE_DIR_READ) { tape->merge_bh_size = 0; if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) ++count; ide_tape_discard_merge_buffer(drive, 0); }
switch (mt_op) { case MTFSF: case MTBSF: idetape_create_space_cmd(&pc, mt_count - count, IDETAPE_SPACE_OVER_FILEMARK); return ide_queue_pc_tail(drive, disk, &pc); case MTFSFM: case MTBSFM: if (!sprev) return -EIO; retval = idetape_space_over_filemarks(drive, MTFSF, mt_count - count); if (retval) return retval; count = (MTBSFM == mt_op ? 1 : -1); return idetape_space_over_filemarks(drive, MTFSF, count); default: printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", mt_op); return -EIO; }}
/* * Our character device read / write functions. * * The tape is optimized to maximize throughput when it is transferring an * integral number of the "continuous transfer limit", which is a parameter of * the specific tape (26kB on my particular tape, 32kB for Onstream). * * As of version 1.3 of the driver, the character device provides an abstract * continuous view of the media - any mix of block sizes (even 1 byte) on the * same backup/restore procedure is supported. The driver will internally * convert the requests to the recommended transfer unit, so that an unmatch * between the user's block size to the recommended size will only result in a * (slightly) increased driver overhead, but will no longer hit performance. * This is not applicable to Onstream. */static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos){ struct ide_tape_obj *tape = file->private_data; ide_drive_t *drive = tape->drive; ssize_t bytes_read, temp, actually_read = 0, rc; ssize_t ret = 0; u16 ctl = *(u16 *)&tape->caps[12];
debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
if (tape->chrdev_dir != IDETAPE_DIR_READ) { if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) if (count > tape->blk_size && (count % tape->blk_size) == 0) tape->user_bs_factor = count / tape->blk_size; } rc = idetape_init_read(drive); if (rc < 0) return rc; if (count == 0) return (0); if (tape->merge_bh_size) { actually_read = min((unsigned int)(tape->merge_bh_size), (unsigned int)count); if (idetape_copy_stage_to_user(tape, buf, actually_read)) ret = -EFAULT; buf += actually_read; tape->merge_bh_size -= actually_read; count -= actually_read; } while (count >= tape->buffer_size) { bytes_read = idetape_add_chrdev_read_request(drive, ctl); if (bytes_read <= 0) goto finish; if (idetape_copy_stage_to_user(tape, buf, bytes_read)) ret = -EFAULT; buf += bytes_read; count -= bytes_read; actually_read += bytes_read; } if (count) { bytes_read = idetape_add_chrdev_read_request(drive, ctl); if (bytes_read <= 0) goto finish; temp = min((unsigned long)count, (unsigned long)bytes_read); if (idetape_copy_stage_to_user(tape, buf, temp)) ret = -EFAULT; actually_read += temp; tape->merge_bh_size = bytes_read-temp; }finish: if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
idetape_space_over_filemarks(drive, MTFSF, 1); return 0; }
return ret ? ret : actually_read;}
static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos){ struct ide_tape_obj *tape = file->private_data; ide_drive_t *drive = tape->drive; ssize_t actually_written = 0; ssize_t ret = 0; u16 ctl = *(u16 *)&tape->caps[12];
/* The drive is write protected. */ if (tape->write_prot) return -EACCES;
debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
/* Initialize write operation */ if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { if (tape->chrdev_dir == IDETAPE_DIR_READ) ide_tape_discard_merge_buffer(drive, 1); if (tape->merge_bh || tape->merge_bh_size) { printk(KERN_ERR "ide-tape: merge_bh_size " "should be 0 now\n"); tape->merge_bh_size = 0; } tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); if (!tape->merge_bh) return -ENOMEM; tape->chrdev_dir = IDETAPE_DIR_WRITE; idetape_init_merge_buffer(tape);
/* * Issue a write 0 command to ensure that DSC handshake is * switched from completion mode to buffer available mode. No * point in issuing this if DSC overlap isn't supported, some * drives (Seagate STT3401A) will return an error. */ if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { ssize_t retval = idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 0, tape->merge_bh); if (retval < 0) { ide_tape_kfree_buffer(tape); tape->merge_bh = NULL; tape->chrdev_dir = IDETAPE_DIR_NONE; return retval; } } } if (count == 0) return (0); if (tape->merge_bh_size) { if (tape->merge_bh_size >= tape->buffer_size) { printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); tape->merge_bh_size = 0; } actually_written = min((unsigned int) (tape->buffer_size - tape->merge_bh_size), (unsigned int)count); if (idetape_copy_stage_from_user(tape, buf, actually_written)) ret = -EFAULT; buf += actually_written; tape->merge_bh_size += actually_written; count -= actually_written;
if (tape->merge_bh_size == tape->buffer_size) { ssize_t retval; tape->merge_bh_size = 0; retval = idetape_add_chrdev_write_request(drive, ctl); if (retval <= 0) return (retval); } } while (count >= tape->buffer_size) { ssize_t retval; if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) ret = -EFAULT; buf += tape->buffer_size; count -= tape->buffer_size; retval = idetape_add_chrdev_write_request(drive, ctl); actually_written += tape->buffer_size; if (retval <= 0) return (retval); } if (count) { actually_written += count; if (idetape_copy_stage_from_user(tape, buf, count)) ret = -EFAULT; tape->merge_bh_size += count; } return ret ? ret : actually_written;}
static int idetape_write_filemark(ide_drive_t *drive){ struct ide_tape_obj *tape = drive->driver_data; struct ide_atapi_pc pc;
/* Write a filemark */ idetape_create_write_filemark_cmd(drive, &pc, 1); if (ide_queue_pc_tail(drive, tape->disk, &pc)) { printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); return -EIO; } return 0;}
/* * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is * requested. * * Note: MTBSF and MTBSFM are not supported when the tape doesn't support * spacing over filemarks in the reverse direction. In this case, MTFSFM is also * usually not supported. * * The following commands are currently not supported: * * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, * MT_ST_WRITE_THRESHOLD. */static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count){ idetape_tape_t *tape = drive->driver_data; struct gendisk *disk = tape->disk; struct ide_atapi_pc pc; int i, retval;
debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", mt_op, mt_count);
switch (mt_op) { case MTFSF: case MTFSFM: case MTBSF: case MTBSFM: if (!mt_count) return 0; return idetape_space_over_filemarks(drive, mt_op, mt_count); default: break; }
switch (mt_op) { case MTWEOF: if (tape->write_prot) return -EACCES; ide_tape_discard_merge_buffer(drive, 1); for (i = 0; i < mt_count; i++) { retval = idetape_write_filemark(drive); if (retval) return retval; } return 0; case MTREW: ide_tape_discard_merge_buffer(drive, 0); if (idetape_rewind_tape(drive)) return -EIO; return 0; case MTLOAD: ide_tape_discard_merge_buffer(drive, 0); return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); case MTUNLOAD: case MTOFFL: /* * If door is locked, attempt to unlock before * attempting to eject. */ if (tape->door_locked) { if (!ide_set_media_lock(drive, disk, 0)) tape->door_locked = DOOR_UNLOCKED; } ide_tape_discard_merge_buffer(drive, 0); retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); if (!retval) clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); return retval; case MTNOP: ide_tape_discard_merge_buffer(drive, 0); return idetape_flush_tape_buffers(drive); case MTRETEN: ide_tape_discard_merge_buffer(drive, 0); return ide_do_start_stop(drive, disk, IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); case MTEOM: idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); return ide_queue_pc_tail(drive, disk, &pc); case MTERASE: (void)idetape_rewind_tape(drive); idetape_create_erase_cmd(&pc); return ide_queue_pc_tail(drive, disk, &pc); case MTSETBLK: if (mt_count) { if (mt_count < tape->blk_size || mt_count % tape->blk_size) return -EIO; tape->user_bs_factor = mt_count / tape->blk_size; clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); } else set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); return 0; case MTSEEK: ide_tape_discard_merge_buffer(drive, 0); return idetape_position_tape(drive, mt_count * tape->user_bs_factor, tape->partition, 0); case MTSETPART: ide_tape_discard_merge_buffer(drive, 0); return idetape_position_tape(drive, 0, mt_count, 0); case MTFSR: case MTBSR: case MTLOCK: retval = ide_set_media_lock(drive, disk, 1); if (retval) return retval; tape->door_locked = DOOR_EXPLICITLY_LOCKED; return 0; case MTUNLOCK: retval = ide_set_media_lock(drive, disk, 0); if (retval) return retval; tape->door_locked = DOOR_UNLOCKED; return 0; default: printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", mt_op); return -EIO; }}
/* * Our character device ioctls. General mtio.h magnetic io commands are * supported here, and not in the corresponding block interface. Our own * ide-tape ioctls are supported on both interfaces. */static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg){ struct ide_tape_obj *tape = file->private_data; ide_drive_t *drive = tape->drive; struct mtop mtop; struct mtget mtget; struct mtpos mtpos; int block_offset = 0, position = tape->first_frame; void __user *argp = (void __user *)arg;
debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { ide_tape_flush_merge_buffer(drive); idetape_flush_tape_buffers(drive); } if (cmd == MTIOCGET || cmd == MTIOCPOS) { block_offset = tape->merge_bh_size / (tape->blk_size * tape->user_bs_factor); position = idetape_read_position(drive); if (position < 0) return -EIO; } switch (cmd) { case MTIOCTOP: if (copy_from_user(&mtop, argp, sizeof(struct mtop))) return -EFAULT; return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); case MTIOCGET: memset(&mtget, 0, sizeof(struct mtget)); mtget.mt_type = MT_ISSCSI2; mtget.mt_blkno = position / tape->user_bs_factor - block_offset; mtget.mt_dsreg = ((tape->blk_size * tape->user_bs_factor) << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
if (tape->drv_write_prot) mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
if (copy_to_user(argp, &mtget, sizeof(struct mtget))) return -EFAULT; return 0; case MTIOCPOS: mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) return -EFAULT; return 0; default: if (tape->chrdev_dir == IDETAPE_DIR_READ) ide_tape_discard_merge_buffer(drive, 1); return idetape_blkdev_ioctl(drive, cmd, arg); }}
/* * Do a mode sense page 0 with block descriptor and if it succeeds set the tape * block size with the reported value. */static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc pc;
idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); if (ide_queue_pc_tail(drive, tape->disk, &pc)) { printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); if (tape->blk_size == 0) { printk(KERN_WARNING "ide-tape: Cannot deal with zero " "block size, assuming 32k\n"); tape->blk_size = 32768; } return; } tape->blk_size = (pc.buf[4 + 5] << 16) + (pc.buf[4 + 6] << 8) + pc.buf[4 + 7]; tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;}
static int idetape_chrdev_open(struct inode *inode, struct file *filp){ unsigned int minor = iminor(inode), i = minor & ~0xc0; ide_drive_t *drive; idetape_tape_t *tape; int retval;
if (i >= MAX_HWIFS * MAX_DRIVES) return -ENXIO;
lock_kernel(); tape = ide_tape_chrdev_get(i); if (!tape) { unlock_kernel(); return -ENXIO; }
debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
/* * We really want to do nonseekable_open(inode, filp); here, but some * versions of tar incorrectly call lseek on tapes and bail out if that * fails. So we disallow pread() and pwrite(), but permit lseeks. */ filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
drive = tape->drive;
filp->private_data = tape;
if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { retval = -EBUSY; goto out_put_tape; }
retval = idetape_wait_ready(drive, 60 * HZ); if (retval) { clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); goto out_put_tape; }
idetape_read_position(drive); if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) (void)idetape_rewind_tape(drive);
/* Read block size and write protect status from drive. */ ide_tape_get_bsize_from_bdesc(drive);
/* Set write protect flag if device is opened as read-only. */ if ((filp->f_flags & O_ACCMODE) == O_RDONLY) tape->write_prot = 1; else tape->write_prot = tape->drv_write_prot;
/* Make sure drive isn't write protected if user wants to write. */ if (tape->write_prot) { if ((filp->f_flags & O_ACCMODE) == O_WRONLY || (filp->f_flags & O_ACCMODE) == O_RDWR) { clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); retval = -EROFS; goto out_put_tape; } }
/* Lock the tape drive door so user can't eject. */ if (tape->chrdev_dir == IDETAPE_DIR_NONE) { if (!ide_set_media_lock(drive, tape->disk, 1)) { if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) tape->door_locked = DOOR_LOCKED; } } unlock_kernel(); return 0;
out_put_tape: ide_tape_put(tape); unlock_kernel(); return retval;}
static void idetape_write_release(ide_drive_t *drive, unsigned int minor){ idetape_tape_t *tape = drive->driver_data;
ide_tape_flush_merge_buffer(drive); tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); if (tape->merge_bh != NULL) { idetape_pad_zeros(drive, tape->blk_size * (tape->user_bs_factor - 1)); ide_tape_kfree_buffer(tape); tape->merge_bh = NULL; } idetape_write_filemark(drive); idetape_flush_tape_buffers(drive); idetape_flush_tape_buffers(drive);}
static int idetape_chrdev_release(struct inode *inode, struct file *filp){ struct ide_tape_obj *tape = filp->private_data; ide_drive_t *drive = tape->drive; unsigned int minor = iminor(inode);
lock_kernel(); tape = drive->driver_data;
debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
if (tape->chrdev_dir == IDETAPE_DIR_WRITE) idetape_write_release(drive, minor); if (tape->chrdev_dir == IDETAPE_DIR_READ) { if (minor < 128) ide_tape_discard_merge_buffer(drive, 1); }
if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) (void) idetape_rewind_tape(drive); if (tape->chrdev_dir == IDETAPE_DIR_NONE) { if (tape->door_locked == DOOR_LOCKED) { if (!ide_set_media_lock(drive, tape->disk, 0)) tape->door_locked = DOOR_UNLOCKED; } } clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); ide_tape_put(tape); unlock_kernel(); return 0;}
static void idetape_get_inquiry_results(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc pc; char fw_rev[4], vendor_id[8], product_id[16];
idetape_create_inquiry_cmd(&pc); if (ide_queue_pc_tail(drive, tape->disk, &pc)) { printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", tape->name); return; } memcpy(vendor_id, &pc.buf[8], 8); memcpy(product_id, &pc.buf[16], 16); memcpy(fw_rev, &pc.buf[32], 4);
ide_fixstring(vendor_id, 8, 0); ide_fixstring(product_id, 16, 0); ide_fixstring(fw_rev, 4, 0);
printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", drive->name, tape->name, vendor_id, product_id, fw_rev);}
/* * Ask the tape about its various parameters. In particular, we will adjust our * data transfer buffer size to the recommended value as returned by the tape. */static void idetape_get_mode_sense_results(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data; struct ide_atapi_pc pc; u8 *caps; u8 speed, max_speed;
idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); if (ide_queue_pc_tail(drive, tape->disk, &pc)) { printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" " some default values\n"); tape->blk_size = 512; put_unaligned(52, (u16 *)&tape->caps[12]); put_unaligned(540, (u16 *)&tape->caps[14]); put_unaligned(6*52, (u16 *)&tape->caps[16]); return; } caps = pc.buf + 4 + pc.buf[3];
/* convert to host order and save for later use */ speed = be16_to_cpup((__be16 *)&caps[14]); max_speed = be16_to_cpup((__be16 *)&caps[8]);
*(u16 *)&caps[8] = max_speed; *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); *(u16 *)&caps[14] = speed; *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]);
if (!speed) { printk(KERN_INFO "ide-tape: %s: invalid tape speed " "(assuming 650KB/sec)\n", drive->name); *(u16 *)&caps[14] = 650; } if (!max_speed) { printk(KERN_INFO "ide-tape: %s: invalid max_speed " "(assuming 650KB/sec)\n", drive->name); *(u16 *)&caps[8] = 650; }
memcpy(&tape->caps, caps, 20);
/* device lacks locking support according to capabilities page */ if ((caps[6] & 1) == 0) drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING;
if (caps[7] & 0x02) tape->blk_size = 512; else if (caps[7] & 0x04) tape->blk_size = 1024;}
#ifdef CONFIG_IDE_PROC_FS#define ide_tape_devset_get(name, field) \static int get_##name(ide_drive_t *drive) \{ \ idetape_tape_t *tape = drive->driver_data; \ return tape->field; \}
#define ide_tape_devset_set(name, field) \static int set_##name(ide_drive_t *drive, int arg) \{ \ idetape_tape_t *tape = drive->driver_data; \ tape->field = arg; \ return 0; \}
#define ide_tape_devset_rw_field(_name, _field) \ide_tape_devset_get(_name, _field) \ide_tape_devset_set(_name, _field) \IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name)
#define ide_tape_devset_r_field(_name, _field) \ide_tape_devset_get(_name, _field) \IDE_DEVSET(_name, 0, get_##_name, NULL)
static int mulf_tdsc(ide_drive_t *drive) { return 1000; }static int divf_tdsc(ide_drive_t *drive) { return HZ; }static int divf_buffer(ide_drive_t *drive) { return 2; }static int divf_buffer_size(ide_drive_t *drive) { return 1024; }
ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP);
ide_tape_devset_rw_field(debug_mask, debug_mask);ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq);
ide_tape_devset_r_field(avg_speed, avg_speed);ide_tape_devset_r_field(speed, caps[14]);ide_tape_devset_r_field(buffer, caps[16]);ide_tape_devset_r_field(buffer_size, buffer_size);
static const struct ide_proc_devset idetape_settings[] = { __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, mulf_tdsc, divf_tdsc), { 0 },};#endif
/* * The function below is called to: * * 1. Initialize our various state variables. * 2. Ask the tape for its capabilities. * 3. Allocate a buffer which will be used for data transfer. The buffer size * is chosen based on the recommendation which we received in step 2. * * Note that at this point ide.c already assigned us an irq, so that we can * queue requests here and wait for their completion. */static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor){ unsigned long t; int speed; int buffer_size; u16 *ctl = (u16 *)&tape->caps[12];
drive->pc_callback = ide_tape_callback; drive->pc_update_buffers = idetape_update_buffers; drive->pc_io_buffers = ide_tape_io_buffers;
spin_lock_init(&tape->lock);
drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP;
if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", tape->name); drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; }
/* Seagate Travan drives do not support DSC overlap. */ if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
tape->minor = minor; tape->name[0] = 'h'; tape->name[1] = 't'; tape->name[2] = '0' + minor; tape->chrdev_dir = IDETAPE_DIR_NONE;
idetape_get_inquiry_results(drive); idetape_get_mode_sense_results(drive); ide_tape_get_bsize_from_bdesc(drive); tape->user_bs_factor = 1; tape->buffer_size = *ctl * tape->blk_size; while (tape->buffer_size > 0xffff) { printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); *ctl /= 2; tape->buffer_size = *ctl * tape->blk_size; } buffer_size = tape->buffer_size; tape->pages_per_buffer = buffer_size / PAGE_SIZE; if (buffer_size % PAGE_SIZE) { tape->pages_per_buffer++; tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; }
/* select the "best" DSC read/write polling freq */ speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
/* * Ensure that the number we got makes sense; limit it within * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. */ tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX); printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " "%lums tDSC%s\n", drive->name, tape->name, *(u16 *)&tape->caps[14], (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, tape->buffer_size / 1024, tape->best_dsc_rw_freq * 1000 / HZ, (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
ide_proc_register_driver(drive, tape->driver);}
static void ide_tape_remove(ide_drive_t *drive){ idetape_tape_t *tape = drive->driver_data;
ide_proc_unregister_driver(drive, tape->driver);
ide_unregister_region(tape->disk);
ide_tape_put(tape);}
static void ide_tape_release(struct kref *kref){ struct ide_tape_obj *tape = to_ide_drv(kref, ide_tape_obj); ide_drive_t *drive = tape->drive; struct gendisk *g = tape->disk;
BUG_ON(tape->merge_bh_size);
drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; drive->driver_data = NULL; device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor + 128)); idetape_devs[tape->minor] = NULL; g->private_data = NULL; put_disk(g); kfree(tape);}
#ifdef CONFIG_IDE_PROC_FSstatic int proc_idetape_read_name (char *page, char **start, off_t off, int count, int *eof, void *data){ ide_drive_t *drive = (ide_drive_t *) data; idetape_tape_t *tape = drive->driver_data; char *out = page; int len;
len = sprintf(out, "%s\n", tape->name); PROC_IDE_READ_RETURN(page, start, off, count, eof, len);}
static ide_proc_entry_t idetape_proc[] = { { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, { NULL, 0, NULL, NULL }};
static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive){ return idetape_proc;}
static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive){ return idetape_settings;}#endif
static int ide_tape_probe(ide_drive_t *);
static ide_driver_t idetape_driver = { .gen_driver = { .owner = THIS_MODULE, .name = "ide-tape", .bus = &ide_bus_type, }, .probe = ide_tape_probe, .remove = ide_tape_remove, .version = IDETAPE_VERSION, .do_request = idetape_do_request, .end_request = idetape_end_request, .error = __ide_error,#ifdef CONFIG_IDE_PROC_FS .proc_entries = ide_tape_proc_entries, .proc_devsets = ide_tape_proc_devsets,#endif};
/* Our character device supporting functions, passed to register_chrdev. */static const struct file_operations idetape_fops = { .owner = THIS_MODULE, .read = idetape_chrdev_read, .write = idetape_chrdev_write, .ioctl = idetape_chrdev_ioctl, .open = idetape_chrdev_open, .release = idetape_chrdev_release,};
static int idetape_open(struct block_device *bdev, fmode_t mode){ struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk);
if (!tape) return -ENXIO;
return 0;}
static int idetape_release(struct gendisk *disk, fmode_t mode){ struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
ide_tape_put(tape); return 0;}
static int idetape_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg){ struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj); ide_drive_t *drive = tape->drive; int err = generic_ide_ioctl(drive, bdev, cmd, arg); if (err == -EINVAL) err = idetape_blkdev_ioctl(drive, cmd, arg); return err;}
static struct block_device_operations idetape_block_ops = { .owner = THIS_MODULE, .open = idetape_open, .release = idetape_release, .locked_ioctl = idetape_ioctl,};
static int ide_tape_probe(ide_drive_t *drive){ idetape_tape_t *tape; struct gendisk *g; int minor;
if (!strstr("ide-tape", drive->driver_req)) goto failed;
if (drive->media != ide_tape) goto failed;
if ((drive->dev_flags & IDE_DFLAG_ID_READ) && ide_check_atapi_device(drive, DRV_NAME) == 0) { printk(KERN_ERR "ide-tape: %s: not supported by this version of" " the driver\n", drive->name); goto failed; } tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); if (tape == NULL) { printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", drive->name); goto failed; }
g = alloc_disk(1 << PARTN_BITS); if (!g) goto out_free_tape;
ide_init_disk(g, drive);
kref_init(&tape->kref);
tape->drive = drive; tape->driver = &idetape_driver; tape->disk = g;
g->private_data = &tape->driver;
drive->driver_data = tape;
mutex_lock(&idetape_ref_mutex); for (minor = 0; idetape_devs[minor]; minor++) ; idetape_devs[minor] = tape; mutex_unlock(&idetape_ref_mutex);
idetape_setup(drive, tape, minor);
device_create(idetape_sysfs_class, &drive->gendev, MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name); device_create(idetape_sysfs_class, &drive->gendev, MKDEV(IDETAPE_MAJOR, minor + 128), NULL, "n%s", tape->name);
g->fops = &idetape_block_ops; ide_register_region(g);
return 0;
out_free_tape: kfree(tape);failed: return -ENODEV;}
static void __exit idetape_exit(void){ driver_unregister(&idetape_driver.gen_driver); class_destroy(idetape_sysfs_class); unregister_chrdev(IDETAPE_MAJOR, "ht");}
static int __init idetape_init(void){ int error = 1; idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); if (IS_ERR(idetape_sysfs_class)) { idetape_sysfs_class = NULL; printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); error = -EBUSY; goto out; }
if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { printk(KERN_ERR "ide-tape: Failed to register chrdev" " interface\n"); error = -EBUSY; goto out_free_class; }
error = driver_register(&idetape_driver.gen_driver); if (error) goto out_free_driver;
return 0;
out_free_driver: driver_unregister(&idetape_driver.gen_driver);out_free_class: class_destroy(idetape_sysfs_class);out: return error;}
MODULE_ALIAS("ide:*m-tape*");module_init(idetape_init);module_exit(idetape_exit);MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");MODULE_LICENSE("GPL"); ÿôèº{.nÇ+?·?®??+%?Ëÿ±éݶ¥?wÿº{.nÇ+?·¥?{±þ'^þ)í?æèw* jg¬±¨ ¶????Ý¢jÿ¾«þG«?éÿ¢¸ ¢·¦j:+v?¨?wèjØm¶?ÿþø ¯ù ®w¥þ?àþf£¢·h??â?úÿ?Ù¥
