mirror of
https://github.com/adulau/aha.git
synced 2024-12-30 12:46:17 +00:00
[PATCH] libata handle the case when device returns/needs extra data
PATCH 2/2: handle the case when device returns/needs extra data Description: Sometimes the device returns/needs extra data than expected. Changes: Modify __atapi_pio_bytes() to handle the case where device returns/needs extra data. - for read case, discard trailing data from the device - for write case, padding zero data to the device Signed-off-by: Albert Lee <albertcc@tw.ibm.com> Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
This commit is contained in:
parent
6ae4cfb571
commit
563a6e1fb0
1 changed files with 25 additions and 3 deletions
|
@ -2697,10 +2697,33 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
|
|||
unsigned char *buf;
|
||||
unsigned int offset, count;
|
||||
|
||||
if (qc->curbytes == qc->nbytes - bytes)
|
||||
if (qc->curbytes + bytes >= qc->nbytes)
|
||||
ap->pio_task_state = PIO_ST_LAST;
|
||||
|
||||
next_sg:
|
||||
if (unlikely(qc->cursg >= qc->n_elem)) {
|
||||
/*
|
||||
* The end of qc->sg is reached and the device expects
|
||||
* more data to transfer. In order not to overrun qc->sg
|
||||
* and fulfill length specified in the byte count register,
|
||||
* - for read case, discard trailing data from the device
|
||||
* - for write case, padding zero data to the device
|
||||
*/
|
||||
u16 pad_buf[1] = { 0 };
|
||||
unsigned int words = bytes >> 1;
|
||||
unsigned int i;
|
||||
|
||||
if (words) /* warning if bytes > 1 */
|
||||
printk(KERN_WARNING "ata%u: %u bytes trailing data\n",
|
||||
ap->id, bytes);
|
||||
|
||||
for (i = 0; i < words; i++)
|
||||
ata_data_xfer(ap, (unsigned char*)pad_buf, 2, do_write);
|
||||
|
||||
ap->pio_task_state = PIO_ST_LAST;
|
||||
return;
|
||||
}
|
||||
|
||||
sg = &qc->sg[qc->cursg];
|
||||
|
||||
page = sg->page;
|
||||
|
@ -2734,9 +2757,8 @@ next_sg:
|
|||
|
||||
kunmap(page);
|
||||
|
||||
if (bytes) {
|
||||
if (bytes)
|
||||
goto next_sg;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
|
|
Loading…
Reference in a new issue