diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2009-02-18 10:54:44 -0500 |
|---|---|---|
| committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2009-03-12 12:58:15 -0500 |
| commit | 5c211caa9f341f9eefbda89436d1440d1eccb3bc (patch) | |
| tree | 4f7204ebacf152ea7057dce984c1db550dbce763 | |
| parent | b3f1f9aa082b2ab86dec4db3d8b1566af345387e (diff) | |
| download | lwn-5c211caa9f341f9eefbda89436d1440d1eccb3bc.tar.gz lwn-5c211caa9f341f9eefbda89436d1440d1eccb3bc.zip | |
[SCSI] sd: tell the user when a disk's capacity is adjusted
This patch (as1188) combines the tests for decrementing a drive's
reported capacity and expands the comment. It also adds an
informational message to the system log, informing the user when the
reported value has been changed.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
| -rw-r--r-- | drivers/scsi/sd.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 4970ae4a62d6..e744ee40be69 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1383,18 +1383,22 @@ repeat: sd_read_protection_type(sdkp, buffer); } - /* Some devices return the total number of sectors, not the - * highest sector number. Make the necessary adjustment. */ - if (sdp->fix_capacity) { + /* Some devices are known to return the total number of blocks, + * not the highest block number. Some devices have versions + * which do this and others which do not. Some devices we might + * suspect of doing this but we don't know for certain. + * + * If we know the reported capacity is wrong, decrement it. If + * we can only guess, then assume the number of blocks is even + * (usually true but not always) and err on the side of lowering + * the capacity. + */ + if (sdp->fix_capacity || + (sdp->guess_capacity && (sdkp->capacity & 0x01))) { + sd_printk(KERN_INFO, sdkp, "Adjusting the sector count " + "from its reported value: %llu\n", + (unsigned long long) sdkp->capacity); --sdkp->capacity; - - /* Some devices have version which report the correct sizes - * and others which do not. We guess size according to a heuristic - * and err on the side of lowering the capacity. */ - } else { - if (sdp->guess_capacity) - if (sdkp->capacity & 0x01) /* odd sizes are odd */ - --sdkp->capacity; } got_data: |