From f932bcea6b7317312ab38df12a84710fc6c67a81 Mon Sep 17 00:00:00 2001 From: Stefan Weinhuber Date: Mon, 9 Aug 2010 18:12:59 +0200 Subject: [S390] dasd: allocate fallback cqr for reserve/release The DASD reserve and release ioctls use the preallocated memory pool of the respective device to build their CCW requests. However, when the device is busy, the pool may already be empty and the ioctl fails. Usually this can be recovered by calling the ioctl again, but in a situation in which we need to issue an unconditional reserve to make a device operational again, this would be not recoverable. To avoid a failure due to lack of memory, DASD device driver will preallocate enough memory for a single reserve/release request, which can be used if normal allocation fails. Signed-off-by: Stefan Weinhuber Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd_eckd.c | 73 ++++++++++++++++++++++++++++++++++-------- 1 file changed, 60 insertions(+), 13 deletions(-) (limited to 'drivers/s390/block') diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index ab84da5592e8..0483b2e76b11 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -82,6 +82,14 @@ static struct ccw_driver dasd_eckd_driver; /* see below */ #define INIT_CQR_UNFORMATTED 1 #define INIT_CQR_ERROR 2 +/* emergency request for reserve/release */ +static struct { + struct dasd_ccw_req cqr; + struct ccw1 ccw; + char data[32]; +} *dasd_reserve_req; +static DEFINE_MUTEX(dasd_reserve_mutex); + /* initial attempt at a probe function. this can be simplified once * the other detection code is gone */ @@ -2645,15 +2653,23 @@ dasd_eckd_release(struct dasd_device *device) struct dasd_ccw_req *cqr; int rc; struct ccw1 *ccw; + int useglobal; if (!capable(CAP_SYS_ADMIN)) return -EACCES; + useglobal = 0; cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device); if (IS_ERR(cqr)) { - DBF_DEV_EVENT(DBF_WARNING, device, "%s", - "Could not allocate initialization request"); - return PTR_ERR(cqr); + mutex_lock(&dasd_reserve_mutex); + useglobal = 1; + cqr = &dasd_reserve_req->cqr; + memset(cqr, 0, sizeof(*cqr)); + memset(&dasd_reserve_req->ccw, 0, + sizeof(dasd_reserve_req->ccw)); + cqr->cpaddr = &dasd_reserve_req->ccw; + cqr->data = &dasd_reserve_req->data; + cqr->magic = DASD_ECKD_MAGIC; } ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_RELEASE; @@ -2671,7 +2687,10 @@ dasd_eckd_release(struct dasd_device *device) rc = dasd_sleep_on_immediatly(cqr); - dasd_sfree_request(cqr, cqr->memdev); + if (useglobal) + mutex_unlock(&dasd_reserve_mutex); + else + dasd_sfree_request(cqr, cqr->memdev); return rc; } @@ -2687,15 +2706,23 @@ dasd_eckd_reserve(struct dasd_device *device) struct dasd_ccw_req *cqr; int rc; struct ccw1 *ccw; + int useglobal; if (!capable(CAP_SYS_ADMIN)) return -EACCES; + useglobal = 0; cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device); if (IS_ERR(cqr)) { - DBF_DEV_EVENT(DBF_WARNING, device, "%s", - "Could not allocate initialization request"); - return PTR_ERR(cqr); + mutex_lock(&dasd_reserve_mutex); + useglobal = 1; + cqr = &dasd_reserve_req->cqr; + memset(cqr, 0, sizeof(*cqr)); + memset(&dasd_reserve_req->ccw, 0, + sizeof(dasd_reserve_req->ccw)); + cqr->cpaddr = &dasd_reserve_req->ccw; + cqr->data = &dasd_reserve_req->data; + cqr->magic = DASD_ECKD_MAGIC; } ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_RESERVE; @@ -2713,7 +2740,10 @@ dasd_eckd_reserve(struct dasd_device *device) rc = dasd_sleep_on_immediatly(cqr); - dasd_sfree_request(cqr, cqr->memdev); + if (useglobal) + mutex_unlock(&dasd_reserve_mutex); + else + dasd_sfree_request(cqr, cqr->memdev); return rc; } @@ -2728,15 +2758,23 @@ dasd_eckd_steal_lock(struct dasd_device *device) struct dasd_ccw_req *cqr; int rc; struct ccw1 *ccw; + int useglobal; if (!capable(CAP_SYS_ADMIN)) return -EACCES; + useglobal = 0; cqr = dasd_smalloc_request(DASD_ECKD_MAGIC, 1, 32, device); if (IS_ERR(cqr)) { - DBF_DEV_EVENT(DBF_WARNING, device, "%s", - "Could not allocate initialization request"); - return PTR_ERR(cqr); + mutex_lock(&dasd_reserve_mutex); + useglobal = 1; + cqr = &dasd_reserve_req->cqr; + memset(cqr, 0, sizeof(*cqr)); + memset(&dasd_reserve_req->ccw, 0, + sizeof(dasd_reserve_req->ccw)); + cqr->cpaddr = &dasd_reserve_req->ccw; + cqr->data = &dasd_reserve_req->data; + cqr->magic = DASD_ECKD_MAGIC; } ccw = cqr->cpaddr; ccw->cmd_code = DASD_ECKD_CCW_SLCK; @@ -2754,7 +2792,10 @@ dasd_eckd_steal_lock(struct dasd_device *device) rc = dasd_sleep_on_immediatly(cqr); - dasd_sfree_request(cqr, cqr->memdev); + if (useglobal) + mutex_unlock(&dasd_reserve_mutex); + else + dasd_sfree_request(cqr, cqr->memdev); return rc; } @@ -3488,10 +3529,15 @@ dasd_eckd_init(void) int ret; ASCEBC(dasd_eckd_discipline.ebcname, 4); + dasd_reserve_req = kmalloc(sizeof(*dasd_reserve_req), + GFP_KERNEL | GFP_DMA); + if (!dasd_reserve_req) + return -ENOMEM; ret = ccw_driver_register(&dasd_eckd_driver); if (!ret) wait_for_device_probe(); - + else + kfree(dasd_reserve_req); return ret; } @@ -3499,6 +3545,7 @@ static void __exit dasd_eckd_cleanup(void) { ccw_driver_unregister(&dasd_eckd_driver); + kfree(dasd_reserve_req); } module_init(dasd_eckd_init); -- cgit v1.2.1 From 7c8faa86290c1a2607d6b768a0b874ec392a5c2a Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Mon, 9 Aug 2010 18:13:00 +0200 Subject: [S390] dasd: tunable missing interrupt handler This feature provides a user interface to specify the timeout for missing interrupts for standard I/O operations. Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd_devmap.c | 44 ++++++++++++++++++++++++++++++++++++++++ drivers/s390/block/dasd_diag.c | 6 ++++-- drivers/s390/block/dasd_eckd.c | 21 +++++++++++++++---- drivers/s390/block/dasd_eckd.h | 7 ++++++- drivers/s390/block/dasd_fba.c | 4 +++- drivers/s390/block/dasd_int.h | 8 +++++++- 6 files changed, 81 insertions(+), 9 deletions(-) (limited to 'drivers/s390/block') diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c index bed7b4634ccd..8d41f3ed38d7 100644 --- a/drivers/s390/block/dasd_devmap.c +++ b/drivers/s390/block/dasd_devmap.c @@ -1083,6 +1083,49 @@ dasd_eer_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store); +/* + * expiration time for default requests + */ +static ssize_t +dasd_expires_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct dasd_device *device; + int len; + + device = dasd_device_from_cdev(to_ccwdev(dev)); + if (IS_ERR(device)) + return -ENODEV; + len = snprintf(buf, PAGE_SIZE, "%lu\n", device->default_expires); + dasd_put_device(device); + return len; +} + +static ssize_t +dasd_expires_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct dasd_device *device; + unsigned long val; + + device = dasd_device_from_cdev(to_ccwdev(dev)); + if (IS_ERR(device)) + return -ENODEV; + + if ((strict_strtoul(buf, 10, &val) != 0) || + (val > DASD_EXPIRES_MAX) || val == 0) { + dasd_put_device(device); + return -EINVAL; + } + + if (val) + device->default_expires = val; + + dasd_put_device(device); + return count; +} + +static DEVICE_ATTR(expires, 0644, dasd_expires_show, dasd_expires_store); + static struct attribute * dasd_attrs[] = { &dev_attr_readonly.attr, &dev_attr_discipline.attr, @@ -1094,6 +1137,7 @@ static struct attribute * dasd_attrs[] = { &dev_attr_eer_enabled.attr, &dev_attr_erplog.attr, &dev_attr_failfast.attr, + &dev_attr_expires.attr, NULL, }; diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c index 687f323cdc38..2b3bc3ec0541 100644 --- a/drivers/s390/block/dasd_diag.c +++ b/drivers/s390/block/dasd_diag.c @@ -43,7 +43,7 @@ MODULE_LICENSE("GPL"); sizeof(struct dasd_diag_req)) / \ sizeof(struct dasd_diag_bio)) / 2) #define DIAG_MAX_RETRIES 32 -#define DIAG_TIMEOUT 50 * HZ +#define DIAG_TIMEOUT 50 static struct dasd_discipline dasd_diag_discipline; @@ -360,6 +360,8 @@ dasd_diag_check_device(struct dasd_device *device) goto out; } + device->default_expires = DIAG_TIMEOUT; + /* Figure out position of label block */ switch (private->rdc_data.vdev_class) { case DEV_CLASS_FBA: @@ -563,7 +565,7 @@ static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev, cqr->startdev = memdev; cqr->memdev = memdev; cqr->block = block; - cqr->expires = DIAG_TIMEOUT; + cqr->expires = memdev->default_expires * HZ; cqr->status = DASD_CQR_FILLED; return cqr; } diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index 0483b2e76b11..66360c24bd48 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -1115,8 +1115,9 @@ dasd_eckd_check_characteristics(struct dasd_device *device) struct dasd_eckd_private *private; struct dasd_block *block; struct dasd_uid temp_uid; - int is_known, rc; + int is_known, rc, i; int readonly; + unsigned long value; if (!ccw_device_is_pathgroup(device->cdev)) { dev_warn(&device->cdev->dev, @@ -1151,6 +1152,18 @@ dasd_eckd_check_characteristics(struct dasd_device *device) if (rc) goto out_err1; + /* set default timeout */ + device->default_expires = DASD_EXPIRES; + if (private->gneq) { + value = 1; + for (i = 0; i < private->gneq->timeout.value; i++) + value = 10 * value; + value = value * private->gneq->timeout.number; + /* do not accept useless values */ + if (value != 0 && value <= DASD_EXPIRES_MAX) + device->default_expires = value; + } + /* Generate device unique id */ rc = dasd_eckd_generate_uid(device); if (rc) @@ -1981,7 +1994,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_single( cqr->startdev = startdev; cqr->memdev = startdev; cqr->block = block; - cqr->expires = 5 * 60 * HZ; /* 5 minutes */ + cqr->expires = startdev->default_expires * HZ; /* default 5 minutes */ cqr->lpm = private->path_data.ppm; cqr->retries = 256; cqr->buildclk = get_clock(); @@ -2158,7 +2171,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_track( cqr->startdev = startdev; cqr->memdev = startdev; cqr->block = block; - cqr->expires = 5 * 60 * HZ; /* 5 minutes */ + cqr->expires = startdev->default_expires * HZ; /* default 5 minutes */ cqr->lpm = private->path_data.ppm; cqr->retries = 256; cqr->buildclk = get_clock(); @@ -2406,7 +2419,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_tpm_track( cqr->startdev = startdev; cqr->memdev = startdev; cqr->block = block; - cqr->expires = 5 * 60 * HZ; /* 5 minutes */ + cqr->expires = startdev->default_expires * HZ; /* default 5 minutes */ cqr->lpm = private->path_data.ppm; cqr->retries = 256; cqr->buildclk = get_clock(); diff --git a/drivers/s390/block/dasd_eckd.h b/drivers/s390/block/dasd_eckd.h index dd6385a5af14..0eb49655a6cd 100644 --- a/drivers/s390/block/dasd_eckd.h +++ b/drivers/s390/block/dasd_eckd.h @@ -320,7 +320,12 @@ struct dasd_gneq { __u8 identifier:2; __u8 reserved:6; } __attribute__ ((packed)) flags; - __u8 reserved[7]; + __u8 reserved[5]; + struct { + __u8 value:2; + __u8 number:6; + } __attribute__ ((packed)) timeout; + __u8 reserved3; __u16 subsystemID; __u8 reserved2[22]; } __attribute__ ((packed)); diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c index 37282b90eecc..bec5486e0e6d 100644 --- a/drivers/s390/block/dasd_fba.c +++ b/drivers/s390/block/dasd_fba.c @@ -163,6 +163,8 @@ dasd_fba_check_characteristics(struct dasd_device *device) return rc; } + device->default_expires = DASD_EXPIRES; + readonly = dasd_device_is_ro(device); if (readonly) set_bit(DASD_FLAG_DEVICE_RO, &device->flags); @@ -370,7 +372,7 @@ static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev, cqr->startdev = memdev; cqr->memdev = memdev; cqr->block = block; - cqr->expires = 5 * 60 * HZ; /* 5 minutes */ + cqr->expires = memdev->default_expires * HZ; /* default 5 minutes */ cqr->retries = 32; cqr->buildclk = get_clock(); cqr->status = DASD_CQR_FILLED; diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h index 49b431d135e0..500678d7116c 100644 --- a/drivers/s390/block/dasd_int.h +++ b/drivers/s390/block/dasd_int.h @@ -186,7 +186,7 @@ struct dasd_ccw_req { /* ... and how */ unsigned long starttime; /* jiffies time of request start */ - int expires; /* expiration period in jiffies */ + unsigned long expires; /* expiration period in jiffies */ char lpm; /* logical path mask */ void *data; /* pointer to data area */ @@ -224,6 +224,9 @@ struct dasd_ccw_req { #define DASD_CQR_CLEARED 0x84 /* request was cleared */ #define DASD_CQR_SUCCESS 0x85 /* request was successful */ +/* default expiration time*/ +#define DASD_EXPIRES 300 +#define DASD_EXPIRES_MAX 40000000 /* per dasd_ccw_req flags */ #define DASD_CQR_FLAGS_USE_ERP 0 /* use ERP for this request */ @@ -404,6 +407,9 @@ struct dasd_device { /* hook for alias management */ struct list_head alias_list; + + /* default expiration time in s */ + unsigned long default_expires; }; struct dasd_block { -- cgit v1.2.1