From 9eb251225ab4dbea3119cfcf4c5194eed223a740 Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Fri, 26 Feb 2010 22:37:46 +0100 Subject: [S390] dasd: fix online/offline race Setting a DASD online and offline in quick succession may cause a kernel panic or let the chhccwdev command wait forever. The Online process is split into two parts. After the first part is finished the offline process may be called. This may result in a situation where the second online processing part tries to set the DASD offline as well. Use a mutex to protect online and offline against each other. Also correct some checking. Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd_genhd.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/s390/block/dasd_genhd.c') diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c index d3198303b93..94f92a1247f 100644 --- a/drivers/s390/block/dasd_genhd.c +++ b/drivers/s390/block/dasd_genhd.c @@ -88,6 +88,7 @@ void dasd_gendisk_free(struct dasd_block *block) if (block->gdp) { del_gendisk(block->gdp); block->gdp->queue = NULL; + block->gdp->private_data = NULL; put_disk(block->gdp); block->gdp = NULL; } -- cgit v1.2.3-70-g09d2 From 33b62a30f78536b976183cc764c08038ac011e0a Mon Sep 17 00:00:00 2001 From: Stefan Weinhuber Date: Mon, 8 Mar 2010 12:26:24 +0100 Subject: [S390] dasd: automatic recognition of read-only devices In z/VM it is possible to attach a device as read-only. To prevent unintentional write requests and subsequent I/O errors, we can detect this configuration using the z/VM DIAG 210 interface and set the respective linux block device to read-only as well. Signed-off-by: Stefan Weinhuber Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd.c | 36 ++++++++++++++++++++++++++++++++++++ drivers/s390/block/dasd_3990_erp.c | 4 ++++ drivers/s390/block/dasd_devmap.c | 13 ++++++++----- drivers/s390/block/dasd_diag.c | 6 ++---- drivers/s390/block/dasd_eckd.c | 10 ++++++++-- drivers/s390/block/dasd_fba.c | 10 ++++++++-- drivers/s390/block/dasd_genhd.c | 3 ++- drivers/s390/block/dasd_int.h | 7 +++++++ drivers/s390/block/dasd_ioctl.c | 6 ++++-- 9 files changed, 79 insertions(+), 16 deletions(-) (limited to 'drivers/s390/block/dasd_genhd.c') diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 4951aa82e9f..bbea90baf98 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -26,6 +26,7 @@ #include #include #include +#include /* This is ugly... */ #define PRINTK_HEADER "dasd:" @@ -2212,6 +2213,13 @@ static int dasd_open(struct block_device *bdev, fmode_t mode) goto out; } + if ((mode & FMODE_WRITE) && + (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) || + (base->features & DASD_FEATURE_READONLY))) { + rc = -EROFS; + goto out; + } + return 0; out: @@ -2289,6 +2297,34 @@ dasd_exit(void) * SECTION: common functions for ccw_driver use */ +/* + * Is the device read-only? + * Note that this function does not report the setting of the + * readonly device attribute, but how it is configured in z/VM. + */ +int dasd_device_is_ro(struct dasd_device *device) +{ + struct ccw_dev_id dev_id; + struct diag210 diag_data; + int rc; + + if (!MACHINE_IS_VM) + return 0; + ccw_device_get_id(device->cdev, &dev_id); + memset(&diag_data, 0, sizeof(diag_data)); + diag_data.vrdcdvno = dev_id.devno; + diag_data.vrdclen = sizeof(diag_data); + rc = diag210(&diag_data); + if (rc == 0 || rc == 2) { + return diag_data.vrdcvfla & 0x80; + } else { + DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d", + dev_id.devno, rc); + return 0; + } +} +EXPORT_SYMBOL_GPL(dasd_device_is_ro); + static void dasd_generic_auto_online(void *data, async_cookie_t cookie) { struct ccw_device *cdev = data; diff --git a/drivers/s390/block/dasd_3990_erp.c b/drivers/s390/block/dasd_3990_erp.c index 44796ba4eb9..51224f76b98 100644 --- a/drivers/s390/block/dasd_3990_erp.c +++ b/drivers/s390/block/dasd_3990_erp.c @@ -1045,6 +1045,10 @@ dasd_3990_erp_com_rej(struct dasd_ccw_req * erp, char *sense) erp->retries = 5; + } else if (sense[1] & SNS1_WRITE_INHIBITED) { + dev_err(&device->cdev->dev, "An I/O request was rejected" + " because writing is inhibited\n"); + erp = dasd_3990_erp_cleanup(erp, DASD_CQR_FAILED); } else { /* fatal error - set status to FAILED internal error 09 - Command Reject */ diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c index d49766f3b94..8e23919c870 100644 --- a/drivers/s390/block/dasd_devmap.c +++ b/drivers/s390/block/dasd_devmap.c @@ -742,6 +742,7 @@ dasd_ro_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct dasd_devmap *devmap; + struct dasd_device *device; int val; char *endp; @@ -758,12 +759,14 @@ dasd_ro_store(struct device *dev, struct device_attribute *attr, devmap->features |= DASD_FEATURE_READONLY; else devmap->features &= ~DASD_FEATURE_READONLY; - if (devmap->device) - devmap->device->features = devmap->features; - if (devmap->device && devmap->device->block - && devmap->device->block->gdp) - set_disk_ro(devmap->device->block->gdp, val); + device = devmap->device; + if (device) { + device->features = devmap->features; + val = val || test_bit(DASD_FLAG_DEVICE_RO, &device->flags); + } spin_unlock(&dasd_devmap_lock); + if (device && device->block && device->block->gdp) + set_disk_ro(device->block->gdp, val); return count; } diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c index 6e14863f5c7..687f323cdc3 100644 --- a/drivers/s390/block/dasd_diag.c +++ b/drivers/s390/block/dasd_diag.c @@ -145,12 +145,10 @@ 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)) { + if (!(test_and_set_bit(DASD_FLAG_DEVICE_RO, &device->flags))) pr_warning("%s: The access mode of a DIAG device " "changed to read-only\n", dev_name(&device->cdev->dev)); - device->features |= DASD_FEATURE_READONLY; - } rc = 0; } if (rc) @@ -449,7 +447,7 @@ dasd_diag_check_device(struct dasd_device *device) rc = -EIO; } else { if (rc == 4) - device->features |= DASD_FEATURE_READONLY; + set_bit(DASD_FLAG_DEVICE_RO, &device->flags); pr_info("%s: New DASD with %ld byte/block, total size %ld " "KB%s\n", dev_name(&device->cdev->dev), (unsigned long) block->bp_block, diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index d7163f904f4..01f4e7a34aa 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -1089,6 +1089,7 @@ dasd_eckd_check_characteristics(struct dasd_device *device) struct dasd_eckd_private *private; struct dasd_block *block; int is_known, rc; + int readonly; if (!ccw_device_is_pathgroup(device->cdev)) { dev_warn(&device->cdev->dev, @@ -1182,15 +1183,20 @@ dasd_eckd_check_characteristics(struct dasd_device *device) else private->real_cyl = private->rdc_data.no_cyl; + readonly = dasd_device_is_ro(device); + if (readonly) + set_bit(DASD_FLAG_DEVICE_RO, &device->flags); + dev_info(&device->cdev->dev, "New DASD %04X/%02X (CU %04X/%02X) " - "with %d cylinders, %d heads, %d sectors\n", + "with %d cylinders, %d heads, %d sectors%s\n", private->rdc_data.dev_type, private->rdc_data.dev_model, private->rdc_data.cu_type, private->rdc_data.cu_model.model, private->real_cyl, private->rdc_data.trk_per_cyl, - private->rdc_data.sec_per_trk); + private->rdc_data.sec_per_trk, + readonly ? ", read-only device" : ""); return 0; out_err3: diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c index 0f152444ac7..37282b90eec 100644 --- a/drivers/s390/block/dasd_fba.c +++ b/drivers/s390/block/dasd_fba.c @@ -124,6 +124,7 @@ dasd_fba_check_characteristics(struct dasd_device *device) struct dasd_fba_private *private; struct ccw_device *cdev = device->cdev; int rc; + int readonly; private = (struct dasd_fba_private *) device->private; if (!private) { @@ -162,16 +163,21 @@ dasd_fba_check_characteristics(struct dasd_device *device) return rc; } + readonly = dasd_device_is_ro(device); + if (readonly) + set_bit(DASD_FLAG_DEVICE_RO, &device->flags); + dev_info(&device->cdev->dev, "New FBA DASD %04X/%02X (CU %04X/%02X) with %d MB " - "and %d B/blk\n", + "and %d B/blk%s\n", cdev->id.dev_type, cdev->id.dev_model, cdev->id.cu_type, cdev->id.cu_model, ((private->rdc_data.blk_bdsa * (private->rdc_data.blk_size >> 9)) >> 11), - private->rdc_data.blk_size); + private->rdc_data.blk_size, + readonly ? ", read-only device" : ""); return 0; } diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c index 94f92a1247f..30a1ca3d08b 100644 --- a/drivers/s390/block/dasd_genhd.c +++ b/drivers/s390/block/dasd_genhd.c @@ -70,7 +70,8 @@ int dasd_gendisk_alloc(struct dasd_block *block) } len += sprintf(gdp->disk_name + len, "%c", 'a'+(base->devindex%26)); - if (block->base->features & DASD_FEATURE_READONLY) + if (base->features & DASD_FEATURE_READONLY || + test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) set_disk_ro(gdp, 1); gdp->private_data = block; gdp->queue = block->request_queue; diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h index ed73ce55082..a91d4a97d4f 100644 --- a/drivers/s390/block/dasd_int.h +++ b/drivers/s390/block/dasd_int.h @@ -436,6 +436,10 @@ struct dasd_block { #define DASD_FLAG_OFFLINE 3 /* device is in offline processing */ #define DASD_FLAG_EER_SNSS 4 /* A SNSS is required */ #define DASD_FLAG_EER_IN_USE 5 /* A SNSS request is running */ +#define DASD_FLAG_DEVICE_RO 6 /* The device itself is read-only. Don't + * confuse this with the user specified + * read-only feature. + */ void dasd_put_device_wake(struct dasd_device *); @@ -609,6 +613,9 @@ char *dasd_get_sense(struct irb *); void dasd_device_set_stop_bits(struct dasd_device *, int); void dasd_device_remove_stop_bits(struct dasd_device *, int); +int dasd_device_is_ro(struct dasd_device *); + + /* externals in dasd_devmap.c */ extern int dasd_max_devindex; extern int dasd_probeonly; diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c index 7039d9cf0fb..3479f8158a1 100644 --- a/drivers/s390/block/dasd_ioctl.c +++ b/drivers/s390/block/dasd_ioctl.c @@ -199,7 +199,8 @@ dasd_ioctl_format(struct block_device *bdev, void __user *argp) if (!argp) return -EINVAL; - if (block->base->features & DASD_FEATURE_READONLY) + if (block->base->features & DASD_FEATURE_READONLY || + test_bit(DASD_FLAG_DEVICE_RO, &block->base->flags)) return -EROFS; if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) return -EFAULT; @@ -349,7 +350,8 @@ dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp) return -EINVAL; if (get_user(intval, (int __user *)argp)) return -EFAULT; - + if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &block->base->flags)) + return -EROFS; set_disk_ro(bdev->bd_disk, intval); return dasd_set_feature(block->base->cdev, DASD_FEATURE_READONLY, intval); } -- cgit v1.2.3-70-g09d2