From 09b6b51b0b6c1b9bb61815baf205e4d74c89ff04 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Tue, 10 Jan 2012 13:43:30 -0500 Subject: SCSI & usb-storage: add flags for VPD pages and REPORT LUNS This patch (as1507) adds a skip_vpd_pages flag to struct scsi_device and a no_report_luns flag to struct scsi_target. The first is used to control whether sd will look at VPD pages for information on block provisioning, limits, and characteristics. The second prevents scsi_report_lun_scan() from issuing a REPORT LUNS command. The patch also modifies usb-storage to set the new flag bits for all USB devices and targets, and to stop adjusting the scsi_level value. Historically we have seen that USB mass-storage devices often don't support VPD pages or REPORT LUNS properly. Until now we have avoided these things by setting the scsi_level to SCSI_2 for all USB devices. But this has the side effect of storing the LUN bits into the second byte of each CDB, and now we have a report of a device which doesn't like that. The best solution is to stop abusing scsi_level and instead have separate flags for VPD pages and REPORT LUNS. Signed-off-by: Alan Stern Reported-by: Perry Wagle CC: Matthew Dharm Cc: James Bottomley Signed-off-by: Greg Kroah-Hartman diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 89da43f..fd37bfb 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1295,6 +1295,7 @@ EXPORT_SYMBOL(int_to_scsilun); * LUNs even if it's older than SCSI-3. * If BLIST_NOREPORTLUN is set, return 1 always. * If BLIST_NOLUN is set, return 0 always. + * If starget->no_report_luns is set, return 1 always. * * Return: * 0: scan completed (or no memory, so further scanning is futile) @@ -1321,6 +1322,7 @@ static int scsi_report_lun_scan(struct scsi_target *starget, int bflags, * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does * support more than 8 LUNs. + * Don't attempt if the target doesn't support REPORT LUNS. */ if (bflags & BLIST_NOREPORTLUN) return 1; @@ -1332,6 +1334,8 @@ static int scsi_report_lun_scan(struct scsi_target *starget, int bflags, return 1; if (bflags & BLIST_NOLUN) return 0; + if (starget->no_report_luns) + return 1; if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { sdev = scsi_alloc_sdev(starget, 0, NULL); diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index c691fb5..d173b90 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2349,7 +2349,7 @@ static int sd_try_extended_inquiry(struct scsi_device *sdp) * some USB ones crash on receiving them, and the pages * we currently ask for are for SPC-3 and beyond */ - if (sdp->scsi_level > SCSI_SPC_2) + if (sdp->scsi_level > SCSI_SPC_2 && !sdp->skip_vpd_pages) return 1; return 0; } diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c index 13b8bcd..dc68cc9 100644 --- a/drivers/usb/storage/scsiglue.c +++ b/drivers/usb/storage/scsiglue.c @@ -197,6 +197,9 @@ static int slave_configure(struct scsi_device *sdev) * page x08, so we will skip it. */ sdev->skip_ms_page_8 = 1; + /* Some devices don't handle VPD pages correctly */ + sdev->skip_vpd_pages = 1; + /* Some disks return the total number of blocks in response * to READ CAPACITY rather than the highest block number. * If this device makes that mistake, tell the sd driver. */ @@ -217,16 +220,6 @@ static int slave_configure(struct scsi_device *sdev) if (sdev->scsi_level > SCSI_SPC_2) us->fflags |= US_FL_SANE_SENSE; - /* Some devices report a SCSI revision level above 2 but are - * unable to handle the REPORT LUNS command (for which - * support is mandatory at level 3). Since we already have - * a Get-Max-LUN request, we won't lose much by setting the - * revision level down to 2. The only devices that would be - * affected are those with sparse LUNs. */ - if (sdev->scsi_level > SCSI_2) - sdev->sdev_target->scsi_level = - sdev->scsi_level = SCSI_2; - /* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable * Hardware Error) when any low-level error occurs, * recoverable or not. Setting this flag tells the SCSI @@ -283,6 +276,18 @@ static int slave_configure(struct scsi_device *sdev) return 0; } +static int target_alloc(struct scsi_target *starget) +{ + /* + * Some USB drives don't support REPORT LUNS, even though they + * report a SCSI revision level above 2. Tell the SCSI layer + * not to issue that command; it will perform a normal sequential + * scan instead. + */ + starget->no_report_luns = 1; + return 0; +} + /* queue a command */ /* This is always called with scsi_lock(host) held */ static int queuecommand_lck(struct scsi_cmnd *srb, @@ -546,6 +551,7 @@ struct scsi_host_template usb_stor_host_template = { .slave_alloc = slave_alloc, .slave_configure = slave_configure, + .target_alloc = target_alloc, /* lots of sg segments can be handled */ .sg_tablesize = SCSI_MAX_SG_CHAIN_SEGMENTS, diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 01cb3c4..b3a1c2d 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -136,6 +136,7 @@ struct scsi_device { unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */ unsigned skip_ms_page_8:1; /* do not use MODE SENSE page 0x08 */ unsigned skip_ms_page_3f:1; /* do not use MODE SENSE page 0x3f */ + unsigned skip_vpd_pages:1; /* do not read VPD pages */ unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */ unsigned no_start_on_add:1; /* do not issue start on add */ unsigned allow_restart:1; /* issue START_UNIT in error handler */ @@ -248,6 +249,8 @@ struct scsi_target { * for the device at a time. */ unsigned int pdt_1f_for_no_lun:1; /* PDT = 0x1f * means no lun present. */ + unsigned int no_report_luns:1; /* Don't use + * REPORT LUNS for scanning. */ /* commands actually active on LLD. protected by host lock. */ unsigned int target_busy; /* -- cgit v0.10.2