diff options
author | Tejun Heo <tj@kernel.org> | 2009-04-19 03:46:02 +0400 |
---|---|---|
committer | Jens Axboe <jens.axboe@oracle.com> | 2009-04-28 09:37:31 +0400 |
commit | eb6a61bb9543aa54d62595e27206b3d3c0293bcc (patch) | |
tree | 97d165ad28f62ff4754caff4ebde30e0506259d7 /drivers/ide/ide-atapi.c | |
parent | 08f370f0a2fb223bf48d0bfa2a173be0393c19dc (diff) | |
download | linux-eb6a61bb9543aa54d62595e27206b3d3c0293bcc.tar.xz |
ide-atapi,tape,floppy: allow ->pc_callback() to change rq->data_len
Impact: allow residual count implementation in ->pc_callback()
rq->data_len has two duties - carrying the number of input bytes on
issue and carrying residual count back to the issuer on completion.
ide-atapi completion callback ->pc_callback() is the right place to do
this but currently ide-atapi depends on rq->data_len carrying the
original request size after calling ->pc_callback() to complete the pc
request.
This patch makes ide_pc_intr(), ide_tape_issue_pc() and
ide_floppy_issue_pc() cache length to complete before calling
->pc_callback() so that it can modify rq->data_len as necessary.
Note: As using rq->data_len for two purposes can make cases like this
incorrect in subtle ways, future changes will introduce separate
field for residual count.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'drivers/ide/ide-atapi.c')
-rw-r--r-- | drivers/ide/ide-atapi.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 5cefe12f5622..3df5442de710 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -409,6 +409,16 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0) dsc = 1; + /* + * ->pc_callback() might change rq->data_len for + * residual count, cache total length. + */ + if (!blk_special_request(rq) && + (drive->media == ide_tape && !rq->bio)) + done = ide_rq_bytes(rq); /* FIXME */ + else + done = blk_rq_bytes(rq); + /* Command finished - Call the callback function */ uptodate = drive->pc_callback(drive, dsc); @@ -417,7 +427,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) if (blk_special_request(rq)) { rq->errors = 0; - done = blk_rq_bytes(rq); error = 0; } else { @@ -426,11 +435,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) rq->errors = -EIO; } - if (drive->media == ide_tape && !rq->bio) - done = ide_rq_bytes(rq); /* FIXME */ - else - done = blk_rq_bytes(rq); - error = uptodate ? 0 : -EIO; } |