From 8bcc24127be12967588db0ad0e614be937ee1d5a Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 7 Dec 2006 19:29:27 -0700 Subject: [SCSI] Add missing completion to scsi_complete_async_scans() If either scsi_complete_async_scans() is called a second time before the first call has finished, or a host scan is started while scsi_complete_async_scans() is still sleeping, it would fail to wake up the other task, which would sleep forever. I've changed the kernel-doc to make it clear that scsi_complete_async_scans() only guarantees that scans which started before it was called are guaranteed to have finished when it returns. I considered making it wait until all scans are completed, but it can't guarantee that no more scans will start before it returns anyway, and it runs the risk of confusing other callers of scsi_complete_async_scans() for hosts actually scanning. Signed-off-by: Matthew Wilcox Signed-off-by: James Bottomley --- drivers/scsi/scsi_scan.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'drivers/scsi/scsi_scan.c') diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 14e635aa44ce..13228312fc4d 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -133,12 +133,10 @@ struct async_scan_data { /** * scsi_complete_async_scans - Wait for asynchronous scans to complete * - * Asynchronous scans add themselves to the scanning_hosts list. Once - * that list is empty, we know that the scans are complete. Rather than - * waking up periodically to check the state of the list, we pretend to be - * a scanning task by adding ourselves at the end of the list and going to - * sleep. When the task before us wakes us up, we take ourselves off the - * list and return. + * When this function returns, any host which started scanning before + * this function was called will have finished its scan. Hosts which + * started scanning after this function was called may or may not have + * finished. */ int scsi_complete_async_scans(void) { @@ -171,6 +169,11 @@ int scsi_complete_async_scans(void) spin_lock(&async_scan_lock); list_del(&data->list); + if (!list_empty(&scanning_hosts)) { + struct async_scan_data *next = list_entry(scanning_hosts.next, + struct async_scan_data, list); + complete(&next->prev_finished); + } done: spin_unlock(&async_scan_lock); -- cgit v1.2.2 From ddaf6fc85459d161c39a70a2cf9e04343dafe47f Mon Sep 17 00:00:00 2001 From: James Bottomley Date: Wed, 13 Dec 2006 10:10:40 -0600 Subject: [SCSI] scsi_scan: fix report lun problems with CDROM or RBC devices Apparently no ATAPI CD/DVD actually supports REPORT LUNS (in spite of claiming scsi-3 compliance, where it's mandatory) and worse, some crash or flake out on being sent the command. This may actually be due to a conflict between SPC and MMC with MMC not listing REPORT LUNS as mandatory. The same standards conflict exists for RBC as well. Fix all of this by reversing the blacklists for CDROM and RBC devices (i.e. now they have to have the BLIST_REPORTLUNS2 flag set even if the inquiry data returns scsi-3 compliance). Signed-off-by: James Bottomley --- drivers/scsi/scsi_scan.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) (limited to 'drivers/scsi/scsi_scan.c') diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 13228312fc4d..b83d03c4deef 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -742,6 +742,14 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, sdev->no_uld_attach = 1; switch (sdev->type = (inq_result[0] & 0x1f)) { + case TYPE_RBC: + /* RBC devices can return SCSI-3 compliance and yet + * still not support REPORT LUNS, so make them act as + * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is + * specifically set */ + if ((*bflags & BLIST_REPORTLUN2) == 0) + *bflags |= BLIST_NOREPORTLUN; + /* fall through */ case TYPE_TAPE: case TYPE_DISK: case TYPE_PRINTER: @@ -752,11 +760,17 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, case TYPE_ENCLOSURE: case TYPE_COMM: case TYPE_RAID: - case TYPE_RBC: sdev->writeable = 1; break; - case TYPE_WORM: case TYPE_ROM: + /* MMC devices can return SCSI-3 compliance and yet + * still not support REPORT LUNS, so make them act as + * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is + * specifically set */ + if ((*bflags & BLIST_REPORTLUN2) == 0) + *bflags |= BLIST_NOREPORTLUN; + /* fall through */ + case TYPE_WORM: sdev->writeable = 0; break; default: -- cgit v1.2.2