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| author | Stefan Weinhuber <wein@de.ibm.com> | 2009-12-07 12:51:48 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-01-06 15:17:15 -0800 |
| commit | 016b73b363d8d717a37e63c267c0c79d40a6d7d3 (patch) | |
| tree | ebd3545d0dc18025c6c9e030610148f6280c29c5 /drivers | |
| parent | 4e9e4fcb0d12ae07cd6e9a9430927eb1dbfb0166 (diff) | |
| download | lwn-016b73b363d8d717a37e63c267c0c79d40a6d7d3.tar.gz lwn-016b73b363d8d717a37e63c267c0c79d40a6d7d3.zip | |
S390: dasd: support DIAG access for read-only devices
commit 22825ab7693fd29769518a0d25ba43c01a50092a upstream.
When a DASD device is used with the DIAG discipline, the DIAG
initialization will indicate success or error with a respective
return code. So far we have interpreted a return code of 4 as error,
but it actually means that the initialization was successful, but
the device is read-only. To allow read-only devices to be used with
DIAG we need to accept a return code of 4 as success.
Re-initialization of the DIAG access is also part of the DIAG error
recovery. If we find that the access mode of a device has been
changed from writable to read-only while the device was in use,
we print an error message.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Stephen Powell <zlinuxman@wowway.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/s390/block/dasd_diag.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c index 85fcb4371054..b4ae447a92c8 100644 --- a/drivers/s390/block/dasd_diag.c +++ b/drivers/s390/block/dasd_diag.c @@ -143,6 +143,15 @@ dasd_diag_erp(struct dasd_device *device) mdsk_term_io(device); rc = mdsk_init_io(device, device->block->bp_block, 0, NULL); + if (rc == 4) { + if (!(device->features & DASD_FEATURE_READONLY)) { + dev_warn(&device->cdev->dev, + "The access mode of a DIAG device changed" + " to read-only"); + device->features |= DASD_FEATURE_READONLY; + } + rc = 0; + } if (rc) DEV_MESSAGE(KERN_WARNING, device, "DIAG ERP unsuccessful, " "rc=%d", rc); @@ -432,16 +441,20 @@ dasd_diag_check_device(struct dasd_device *device) for (sb = 512; sb < bsize; sb = sb << 1) block->s2b_shift++; rc = mdsk_init_io(device, block->bp_block, 0, NULL); - if (rc) { + if (rc && (rc != 4)) { DEV_MESSAGE(KERN_WARNING, device, "DIAG initialization " "failed (rc=%d)", rc); rc = -EIO; } else { + if (rc == 4) + device->features |= DASD_FEATURE_READONLY; DEV_MESSAGE(KERN_INFO, device, - "(%ld B/blk): %ldkB", + "(%ld B/blk): %ldkB%s", (unsigned long) block->bp_block, (unsigned long) (block->blocks << - block->s2b_shift) >> 1); + block->s2b_shift) >> 1, + (rc == 4) ? ", read-only device" : ""); + rc = 0; } out_label: free_page((long) label); |