From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Taken from http://bugzilla.kernel.org/show_bug.cgi?id=8904 An updated (by Albert, I assume) version of the fourteen-month-old patch here: http://marc.info/?l=linux-kernel&m=115412002912837&w=2 Apparently fixes the bug described at http://bugzilla.kernel.org/show_bug.cgi?id=8904 Needs some TLC. Perhaps urgently. Cc: Albert Lee <albertcc@xxxxxxxxxx> Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxx> Cc: Tejun Heo <htejun@xxxxxxxxx> Cc: Jens Axboe <jens.axboe@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/scsi/scsi_ioctl.c | 2 +- drivers/scsi/scsi_lib.c | 20 ++++++++++++++++++-- drivers/scsi/sd.c | 2 +- drivers/scsi/sr.c | 15 +++++++++------ include/scsi/scsi_device.h | 2 +- 5 files changed, 30 insertions(+), 11 deletions(-) diff -puN drivers/scsi/scsi_ioctl.c~scsi-early-detection-of-medium-not-present-updated drivers/scsi/scsi_ioctl.c --- a/drivers/scsi/scsi_ioctl.c~scsi-early-detection-of-medium-not-present-updated +++ a/drivers/scsi/scsi_ioctl.c @@ -239,7 +239,7 @@ int scsi_ioctl(struct scsi_device *sdev, return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); case SCSI_IOCTL_TEST_UNIT_READY: return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT, - NORMAL_RETRIES); + NORMAL_RETRIES, NULL); case SCSI_IOCTL_START_UNIT: scsi_cmd[0] = START_STOP; scsi_cmd[1] = 0; diff -puN drivers/scsi/scsi_lib.c~scsi-early-detection-of-medium-not-present-updated drivers/scsi/scsi_lib.c --- a/drivers/scsi/scsi_lib.c~scsi-early-detection-of-medium-not-present-updated +++ a/drivers/scsi/scsi_lib.c @@ -1875,15 +1875,26 @@ scsi_mode_sense(struct scsi_device *sdev } EXPORT_SYMBOL(scsi_mode_sense); +/** + * scsi_test_unit_ready - test if unit is ready + * @sdev: scsi device to change the state of. + * @timeout: command timeout + * @retries: number of retries before failing + * @media_maybe_present: 1 if media maybe present or not. + * 0 if media not present. + * + * Returns zero if unsuccessful or an error if TUR failed. + **/ int -scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries) +scsi_test_unit_ready(struct scsi_device *sdev, int timeout, int retries, int *media_maybe_present) { char cmd[] = { TEST_UNIT_READY, 0, 0, 0, 0, 0, }; struct scsi_sense_hdr sshdr; int result; - + int maybe_present = 1; + result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0, &sshdr, timeout, retries); @@ -1892,10 +1903,15 @@ scsi_test_unit_ready(struct scsi_device if ((scsi_sense_valid(&sshdr)) && ((sshdr.sense_key == UNIT_ATTENTION) || (sshdr.sense_key == NOT_READY))) { + if (sshdr.asc == 0x3A) + maybe_present = 0; sdev->changed = 1; result = 0; } } + + if (media_maybe_present) + *media_maybe_present = maybe_present; return result; } EXPORT_SYMBOL(scsi_test_unit_ready); diff -puN drivers/scsi/sd.c~scsi-early-detection-of-medium-not-present-updated drivers/scsi/sd.c --- a/drivers/scsi/sd.c~scsi-early-detection-of-medium-not-present-updated +++ a/drivers/scsi/sd.c @@ -759,7 +759,7 @@ static int sd_media_changed(struct gendi retval = -ENODEV; if (scsi_block_when_processing_errors(sdp)) - retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES); + retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES, NULL); /* * Unable to test, unit probably not ready. This usually diff -puN drivers/scsi/sr.c~scsi-early-detection-of-medium-not-present-updated drivers/scsi/sr.c --- a/drivers/scsi/sr.c~scsi-early-detection-of-medium-not-present-updated +++ a/drivers/scsi/sr.c @@ -177,18 +177,21 @@ static int sr_media_change(struct cdrom_ { struct scsi_cd *cd = cdi->handle; int retval; + int media_maybe_present; if (CDSL_CURRENT != slot) { /* no changer support */ return -EINVAL; } - retval = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES); - if (retval) { - /* Unable to test, unit probably not ready. This usually - * means there is no disc in the drive. Mark as changed, - * and we will figure it out later once the drive is - * available again. */ + retval = scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, + &media_maybe_present); + if (retval || !media_maybe_present) { + /* Media not present or unable to test, unit probably not + * ready. This usually means there is no disc in the drive. + * Mark as changed, and we will figure it out later once + * the drive is available again. + */ cd->device->changed = 1; /* This will force a flush, if called from check_disk_change */ retval = 1; diff -puN include/scsi/scsi_device.h~scsi-early-detection-of-medium-not-present-updated include/scsi/scsi_device.h --- a/include/scsi/scsi_device.h~scsi-early-detection-of-medium-not-present-updated +++ a/include/scsi/scsi_device.h @@ -283,7 +283,7 @@ extern int scsi_mode_select(struct scsi_ struct scsi_mode_data *data, struct scsi_sense_hdr *); extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout, - int retries); + int retries, int *media_maybe_present); extern int scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state); extern int scsi_device_event_notify(struct scsi_device *sdev, _ - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
