From 6f4267e3bd1211b3d09130e626b0b3d885077610 Mon Sep 17 00:00:00 2001 From: James Bottomley Date: Fri, 22 Aug 2008 16:53:31 -0500 Subject: [SCSI] Update the SCSI state model to allow blocking in the created state Brian King reported that fibre channel devices can oops during scanning if their ports block (because the device goes from CREATED -> BLOCK -> RUNNING rather than CREATED -> BLOCK -> CREATED). Fix this by adding a new state: CREATED_BLOCK which can only transition back to CREATED and disallow the CREATED -> BLOCK transition. Now both the created and blocked states that the mid-layer recognises can include CREATED_BLOCK. Signed-off-by: James Bottomley --- drivers/scsi/scsi_lib.c | 39 ++++++++++++++++++++++++++++++--------- drivers/scsi/scsi_scan.c | 16 ++++++++++++++-- drivers/scsi/scsi_sysfs.c | 1 + 3 files changed, 45 insertions(+), 11 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 62307bd794a..d2884bffa1b 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1251,6 +1251,7 @@ int scsi_prep_state_check(struct scsi_device *sdev, struct request *req) break; case SDEV_QUIESCE: case SDEV_BLOCK: + case SDEV_CREATED_BLOCK: /* * If the devices is blocked we defer normal commands. */ @@ -2064,10 +2065,13 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) switch (state) { case SDEV_CREATED: - /* There are no legal states that come back to - * created. This is the manually initialised start - * state */ - goto illegal; + switch (oldstate) { + case SDEV_CREATED_BLOCK: + break; + default: + goto illegal; + } + break; case SDEV_RUNNING: switch (oldstate) { @@ -2105,8 +2109,17 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) case SDEV_BLOCK: switch (oldstate) { - case SDEV_CREATED: case SDEV_RUNNING: + case SDEV_CREATED_BLOCK: + break; + default: + goto illegal; + } + break; + + case SDEV_CREATED_BLOCK: + switch (oldstate) { + case SDEV_CREATED: break; default: goto illegal; @@ -2394,8 +2407,12 @@ scsi_internal_device_block(struct scsi_device *sdev) int err = 0; err = scsi_device_set_state(sdev, SDEV_BLOCK); - if (err) - return err; + if (err) { + err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK); + + if (err) + return err; + } /* * The device has transitioned to SDEV_BLOCK. Stop the @@ -2438,8 +2455,12 @@ scsi_internal_device_unblock(struct scsi_device *sdev) * and goose the device queue if successful. */ err = scsi_device_set_state(sdev, SDEV_RUNNING); - if (err) - return err; + if (err) { + err = scsi_device_set_state(sdev, SDEV_CREATED); + + if (err) + return err; + } spin_lock_irqsave(q->queue_lock, flags); blk_start_queue(q); diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 2926baaac31..334862e26a1 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -730,6 +730,8 @@ static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, int *bflags, int async) { + int ret; + /* * XXX do not save the inquiry, since it can change underneath us, * save just vendor/model/rev. @@ -885,7 +887,17 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, /* set the device running here so that slave configure * may do I/O */ - scsi_device_set_state(sdev, SDEV_RUNNING); + ret = scsi_device_set_state(sdev, SDEV_RUNNING); + if (ret) { + ret = scsi_device_set_state(sdev, SDEV_BLOCK); + + if (ret) { + sdev_printk(KERN_ERR, sdev, + "in wrong state %s to complete scan\n", + scsi_device_state_name(sdev->sdev_state)); + return SCSI_SCAN_NO_RESPONSE; + } + } if (*bflags & BLIST_MS_192_BYTES_FOR_3F) sdev->use_192_bytes_for_3f = 1; @@ -899,7 +911,7 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, transport_configure_device(&sdev->sdev_gendev); if (sdev->host->hostt->slave_configure) { - int ret = sdev->host->hostt->slave_configure(sdev); + ret = sdev->host->hostt->slave_configure(sdev); if (ret) { /* * if LLDD reports slave not present, don't clutter diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index ab3c71869be..09d311d559d 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -34,6 +34,7 @@ static const struct { { SDEV_QUIESCE, "quiesce" }, { SDEV_OFFLINE, "offline" }, { SDEV_BLOCK, "blocked" }, + { SDEV_CREATED_BLOCK, "created-blocked" }, }; const char *scsi_device_state_name(enum scsi_device_state state) -- cgit v1.2.3