From 5920dadfb4aec6c1372c5570e71bcd3b4837e63c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 15 Jul 2009 17:11:41 +0900 Subject: libata: accept late unlocking of HPA On certain configurations, HPA isn't or can't be unlocked during probing but it somehow ends up unlocked afterwards. In the following thread, the problem can be reliably reproduced after resuming from STR. The BIOS turns on HPA during boot but forgets to do it during resume. http://thread.gmane.org/gmane.linux.kernel/858310 This patch updates libata revalidation such that it considers native n_sectors. If the device size has increased to match native n_sectors, it's assumed that HPA has been unlocked involuntarily and the device is recognized as the same one. This should be fairly safe while nicely working around the problem. Signed-off-by: Tejun Heo Reported-by: Christof Warlich Signed-off-by: Jeff Garzik --- drivers/ata/libata-core.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) (limited to 'drivers') diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 2c6aedaef71..8ac98ff16d7 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -1515,6 +1515,7 @@ static int ata_hpa_resize(struct ata_device *dev) return rc; } + dev->n_native_sectors = native_sectors; /* nothing to do? */ if (native_sectors <= sectors || !ata_ignore_hpa) { @@ -4099,6 +4100,7 @@ int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class, unsigned int readid_flags) { u64 n_sectors = dev->n_sectors; + u64 n_native_sectors = dev->n_native_sectors; int rc; if (!ata_dev_enabled(dev)) @@ -4128,16 +4130,30 @@ int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class, /* verify n_sectors hasn't changed */ if (dev->class == ATA_DEV_ATA && n_sectors && dev->n_sectors != n_sectors) { - ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch " + ata_dev_printk(dev, KERN_WARNING, "n_sectors mismatch " "%llu != %llu\n", (unsigned long long)n_sectors, (unsigned long long)dev->n_sectors); - - /* restore original n_sectors */ - dev->n_sectors = n_sectors; - - rc = -ENODEV; - goto fail; + /* + * Something could have caused HPA to be unlocked + * involuntarily. If n_native_sectors hasn't changed + * and the new size matches it, keep the device. + */ + if (dev->n_native_sectors == n_native_sectors && + dev->n_sectors > n_sectors && + dev->n_sectors == n_native_sectors) { + ata_dev_printk(dev, KERN_WARNING, + "new n_sectors matches native, probably " + "late HPA unlock, continuing\n"); + /* keep using the old n_sectors */ + dev->n_sectors = n_sectors; + } else { + /* restore original n_[native]_sectors and fail */ + dev->n_native_sectors = n_native_sectors; + dev->n_sectors = n_sectors; + rc = -ENODEV; + goto fail; + } } return 0; -- cgit v1.2.3-18-g5258