[PATCH 12/15] ide-tape: fix READ POSITION cmd handling

Borislav Petkov
2009-05-15T05:14:27Z

ide-tape used to issue READ POSITION in several places and the
evaluation of the returned READ POSITION data was done in the
->pc_callback. Convert it to use local buffer and move that
evaluation chunk in the idetape_read_position(). Additionally, fold
idetape_create_read_position_cmd() into it, too, thus concentrating READ
POSITION handling in one method only and making all places call that.

Finally, mv {idetape,ide_tape}_read_position.

There should be no functional change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
---
drivers/ide/ide-tape.c | 102 +++++++++++++++++++++++-------------------------
1 files changed, 49 insertions(+), 53 deletions(-)

diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index 1a8c940..ead2734 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -386,30 +386,7 @@ static int ide_tape_callback(ide_drive_t *drive, int dsc)
uptodate = 0;
err = 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;
- err = IDE_DRV_ERROR_GENERAL;
- } 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);
- }
}
-
rq->errors = err;

return uptodate;
@@ -778,26 +755,44 @@ static int idetape_flush_tape_buffers(ide_drive_t *drive)
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)
+static int ide_tape_read_position(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc pc;
- int position;
+ u8 buf[20];

debug_log(DBG_PROCS, "Enter %s\n", __func__);

- idetape_create_read_position_cmd(&pc);
- if (ide_queue_pc_tail(drive, tape->disk, &pc, pc.buf, pc.req_xfer))
+ /* prep cmd */
+ ide_init_pc(&pc);
+ pc.c[0] = READ_POSITION;
+ pc.req_xfer = 20;
+
+ if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer))
return -1;
- position = tape->first_frame;
- return position;
+
+ if (!pc.error) {
+ debug_log(DBG_SENSE, "BOP - %s\n",
+ (buf[0] & 0x80) ? "Yes" : "No");
+ debug_log(DBG_SENSE, "EOP - %s\n",
+ (buf[0] & 0x40) ? "Yes" : "No");
+
+ if (buf[0] & 0x4) {
+ printk(KERN_INFO "ide-tape: Block location is unknown"
+ "to the tape\n");
+ clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags);
+ return -1;
+ } else {
+ debug_log(DBG_SENSE, "Block Location - %u\n",
+ be32_to_cpup((__be32 *)&buf[4]));
+
+ tape->partition = buf[1];
+ tape->first_frame = be32_to_cpup((__be32 *)&buf[4]);
+ set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags);
+ }
+ }
+
+ return tape->first_frame;
}

static void idetape_create_locate_cmd(ide_drive_t *drive,
@@ -840,19 +835,21 @@ static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
{
idetape_tape_t *tape = drive->driver_data;
struct gendisk *disk = tape->disk;
- int retval;
+ int ret;
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, NULL, 0);
- if (retval)
- return (retval);
+ ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
+ if (ret)
+ return ret;

- idetape_create_read_position_cmd(&pc);
- return ide_queue_pc_tail(drive, disk, &pc, pc.buf, pc.req_xfer);
+ ret = ide_tape_read_position(drive);
+ if (ret < 0)
+ return ret;
+ return 0;
}

static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
@@ -863,7 +860,7 @@ static void ide_tape_discard_merge_buffer(ide_drive_t *drive,

__ide_tape_discard_merge_buffer(drive);
if (restore_position) {
- position = idetape_read_position(drive);
+ position = ide_tape_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"
@@ -1042,20 +1039,19 @@ 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;
+ int ret;

debug_log(DBG_SENSE, "Enter %s\n", __func__);

idetape_create_rewind_cmd(drive, &pc);
- retval = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
- if (retval)
- return retval;
+ ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
+ if (ret)
+ return ret;

- idetape_create_read_position_cmd(&pc);
- retval = ide_queue_pc_tail(drive, disk, &pc, pc.buf, pc.req_xfer);
- if (retval)
- return retval;
+ ret = ide_tape_read_position(drive);
+ if (ret < 0)
+ return ret;
return 0;
}

@@ -1413,7 +1409,7 @@ static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
if (cmd == MTIOCGET || cmd == MTIOCPOS) {
block_offset = tape->valid /
(tape->blk_size * tape->user_bs_factor);
- position = idetape_read_position(drive);
+ position = ide_tape_read_position(drive);
if (position < 0)
return -EIO;
}
@@ -1516,7 +1512,7 @@ static int idetape_chrdev_open(struct inode *inode, struct file *filp)
goto out_put_tape;
}

- idetape_read_position(drive);
+ ide_tape_read_position(drive);
if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags))
(void)idetape_rewind_tape(drive);

--
1.6.3