diff options
Diffstat (limited to 'drivers/ata/libata-scsi.c')
| -rw-r--r-- | drivers/ata/libata-scsi.c | 40 |
1 files changed, 37 insertions, 3 deletions
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 0101af541436..9933b4db7caf 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -112,12 +112,14 @@ static const char *ata_lpm_policy_names[] = { [ATA_LPM_MIN_POWER] = "min_power", }; -static ssize_t ata_scsi_lpm_store(struct device *dev, +static ssize_t ata_scsi_lpm_store(struct device *device, struct device_attribute *attr, const char *buf, size_t count) { - struct Scsi_Host *shost = class_to_shost(dev); + struct Scsi_Host *shost = class_to_shost(device); struct ata_port *ap = ata_shost_to_port(shost); + struct ata_link *link; + struct ata_device *dev; enum ata_lpm_policy policy; unsigned long flags; @@ -133,10 +135,20 @@ static ssize_t ata_scsi_lpm_store(struct device *dev, return -EINVAL; spin_lock_irqsave(ap->lock, flags); + + ata_for_each_link(link, ap, EDGE) { + ata_for_each_dev(dev, &ap->link, ENABLED) { + if (dev->horkage & ATA_HORKAGE_NOLPM) { + count = -EOPNOTSUPP; + goto out_unlock; + } + } + } + ap->target_lpm_policy = policy; ata_port_schedule_eh(ap); +out_unlock: spin_unlock_irqrestore(ap->lock, flags); - return count; } @@ -3614,6 +3626,7 @@ int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht) shost->max_lun = 1; shost->max_channel = 1; shost->max_cmd_len = 16; + shost->no_write_same = 1; /* Schedule policy is determined by ->qc_defer() * callback and it needs to see every deferred qc. @@ -3863,6 +3876,27 @@ void ata_scsi_hotplug(struct work_struct *work) return; } + /* + * XXX - UGLY HACK + * + * The block layer suspend/resume path is fundamentally broken due + * to freezable kthreads and workqueue and may deadlock if a block + * device gets removed while resume is in progress. I don't know + * what the solution is short of removing freezable kthreads and + * workqueues altogether. + * + * The following is an ugly hack to avoid kicking off device + * removal while freezer is active. This is a joke but does avoid + * this particular deadlock scenario. + * + * https://bugzilla.kernel.org/show_bug.cgi?id=62801 + * http://marc.info/?l=linux-kernel&m=138695698516487 + */ +#ifdef CONFIG_FREEZER + while (pm_freezing) + msleep(10); +#endif + DPRINTK("ENTER\n"); mutex_lock(&ap->scsi_scan_mutex); |