Skip to content

Commit

Permalink
ide-cd: use scatterlists for PIO transfers (non-fs requests) (v2)
Browse files Browse the repository at this point in the history 
Convert ide-cd to use scatterlists for PIO transfers and get rid of
partial completions (except on error) also for non-fs requests.

v2:
Do not map dataless commands to an sg since it oopses on the virt_to_page()
translation check when DEBUG_VIRTUAL is enabled.  (from Borislav Petkov,
reported/bisected-by Tetsuo Handa).

Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
  • Loading branch information
Bartlomiej Zolnierkiewicz committed Mar 31, 2009
1 parent 8652b31 commit c7ec899
Showing 1 changed file with 30 additions and 70 deletions.
100 changes: 30 additions & 70 deletions drivers/ide/ide-cd.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -509,20 +509,25 @@ static int ide_cd_check_ireason(ide_drive_t *drive, struct request *rq,
return -1;
}

static void ide_cd_request_sense_fixup(ide_drive_t *drive, struct request *rq)
static void ide_cd_request_sense_fixup(ide_drive_t *drive, struct ide_cmd *cmd)
{
struct request *rq = cmd->rq;

ide_debug_log(IDE_DBG_FUNC, "rq->cmd[0]: 0x%x", rq->cmd[0]);

/*
* Some of the trailing request sense fields are optional,
* and some drives don't send them. Sigh.
*/
if (rq->cmd[0] == GPCMD_REQUEST_SENSE &&
rq->data_len > 0 && rq->data_len <= 5)
while (rq->data_len > 0) {
*(u8 *)rq->data++ = 0;
--rq->data_len;
cmd->nleft > 0 && cmd->nleft <= 5) {
unsigned int ofs = cmd->nbytes - cmd->nleft;

while (cmd->nleft > 0) {
*((u8 *)rq->data + ofs++) = 0;
cmd->nleft--;
}
}
}

int ide_cd_queue_pc(ide_drive_t *drive, const unsigned char *cmd,
Expand Down Expand Up @@ -613,22 +618,11 @@ static void ide_cd_error_cmd(ide_drive_t *drive, struct ide_cmd *cmd)
ide_complete_rq(drive, 0, nr_bytes);
}

/*
* Called from blk_end_request_callback() after the data of the request is
* completed and before the request itself is completed. By returning value '1',
* blk_end_request_callback() returns immediately without completing it.
*/
static int cdrom_newpc_intr_dummy_cb(struct request *rq)
{
return 1;
}

static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
struct ide_cmd *cmd = &hwif->cmd;
struct request *rq = hwif->rq;
xfer_func_t *xferfunc;
ide_expiry_t *expiry = NULL;
int dma_error = 0, dma, stat, thislen, uptodate = 0;
int write = (rq_data_dir(rq) == WRITE) ? 1 : 0, rc, nsectors;
Expand Down Expand Up @@ -678,7 +672,7 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)

ide_read_bcount_and_ireason(drive, &len, &ireason);

thislen = blk_fs_request(rq) ? len : rq->data_len;
thislen = blk_fs_request(rq) ? len : cmd->nleft;
if (thislen > len)
thislen = len;

Expand All @@ -702,9 +696,9 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
uptodate = 0;
}
} else if (!blk_pc_request(rq)) {
ide_cd_request_sense_fixup(drive, rq);
ide_cd_request_sense_fixup(drive, cmd);
/* complain if we still have data left to transfer */
uptodate = rq->data_len ? 0 : 1;
uptodate = cmd->nleft ? 0 : 1;
if (uptodate == 0)
rq->cmd_flags |= REQ_FAILED;
}
Expand All @@ -718,35 +712,15 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)

cmd->last_xfer_len = 0;

if (ireason == 0) {
write = 1;
xferfunc = hwif->tp_ops->output_data;
} else {
write = 0;
xferfunc = hwif->tp_ops->input_data;
}

ide_debug_log(IDE_DBG_PC, "data transfer, rq->cmd_type: 0x%x, "
"ireason: 0x%x",
rq->cmd_type, ireason);

/* transfer data */
while (thislen > 0) {
u8 *ptr = blk_fs_request(rq) ? NULL : rq->data;
int blen = rq->data_len;

/* bio backed? */
if (rq->bio) {
if (blk_fs_request(rq)) {
blen = min_t(int, thislen, cmd->nleft);
} else {
ptr = bio_data(rq->bio);
blen = bio_iovec(rq->bio)->bv_len;
}
}
int blen = min_t(int, thislen, cmd->nleft);

if ((blk_fs_request(rq) && cmd->nleft == 0) ||
(blk_fs_request(rq) == 0 && ptr == NULL)) {
if (cmd->nleft == 0) {
if (blk_fs_request(rq) && !write)
/*
* If the buffers are full, pipe the rest into
Expand All @@ -763,33 +737,12 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
break;
}

if (blen > thislen)
blen = thislen;

if (blk_fs_request(rq)) {
ide_pio_bytes(drive, cmd, write, blen);
cmd->last_xfer_len += blen;
} else
xferfunc(drive, NULL, ptr, blen);
ide_pio_bytes(drive, cmd, write, blen);
cmd->last_xfer_len += blen;

thislen -= blen;
len -= blen;

if (blk_fs_request(rq) == 0) {
rq->data_len -= blen;

/*
* The request can't be completed until DRQ is cleared.
* So complete the data, but don't complete the request
* using the dummy function for the callback feature
* of blk_end_request_callback().
*/
if (rq->bio)
blk_end_request_callback(rq, 0, blen,
cdrom_newpc_intr_dummy_cb);
else
rq->data += blen;
}
if (sense && write == 0)
rq->sense_len += blen;
}
Expand All @@ -814,8 +767,7 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
if (blk_pc_request(rq) && rc == 0) {
unsigned int dlen = rq->data_len;

if (dma)
rq->data_len = 0;
rq->data_len = 0;

if (blk_end_request(rq, 0, dlen))
BUG();
Expand All @@ -828,13 +780,14 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
if (blk_fs_request(rq)) {
if (cmd->nleft == 0)
uptodate = 1;
if (uptodate == 0)
ide_cd_error_cmd(drive, cmd);
} else {
if (uptodate <= 0 && rq->errors == 0)
rq->errors = -EIO;
}

if (uptodate == 0)
ide_cd_error_cmd(drive, cmd);

/* make sure it's fully ended */
if (blk_pc_request(rq))
nsectors = (rq->data_len + 511) >> 9;
Expand All @@ -844,6 +797,12 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
if (nsectors == 0)
nsectors = 1;

if (blk_fs_request(rq) == 0) {
rq->data_len -= (cmd->nbytes - cmd->nleft);
if (uptodate == 0 && (cmd->tf_flags & IDE_TFLAG_WRITE))
rq->data_len += cmd->last_xfer_len;
}

ide_complete_rq(drive, uptodate ? 0 : -EIO, nsectors << 9);

if (sense && rc == 2)
Expand Down Expand Up @@ -971,8 +930,9 @@ static ide_startstop_t ide_cd_do_request(ide_drive_t *drive, struct request *rq,

cmd.rq = rq;

if (blk_fs_request(rq)) {
ide_init_sg_cmd(&cmd, rq->nr_sectors << 9);
if (blk_fs_request(rq) || rq->data_len) {
ide_init_sg_cmd(&cmd, blk_fs_request(rq) ? (rq->nr_sectors << 9)
: rq->data_len);
ide_map_sg(drive, &cmd);
}

Expand Down

0 comments on commit c7ec899

Please sign in to comment.