X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fs390%2Fblock%2Fdcssblk.c;h=a66b17b65296e7d73ddc6d8f0ecea6c5ac864b6f;hb=6a77f38946aaee1cd85eeec6cf4229b204c15071;hp=8a30b525002b2b020404575c26a4ca38eefbd27a;hpb=5273a3df6485dc2ad6aa7ddd441b9a21970f003b;p=linux-2.6.git diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c index 8a30b5250..a66b17b65 100644 --- a/drivers/s390/block/dcssblk.c +++ b/drivers/s390/block/dcssblk.c @@ -5,6 +5,7 @@ */ #include +#include #include #include #include @@ -19,6 +20,7 @@ //#define DCSSBLK_DEBUG /* Debug messages on/off */ #define DCSSBLK_NAME "dcssblk" #define DCSSBLK_MINORS_PER_DISK 1 +#define DCSSBLK_PARM_LEN 400 #ifdef DCSSBLK_DEBUG #define PRINT_DEBUG(x...) printk(KERN_DEBUG DCSSBLK_NAME " debug: " x) @@ -34,6 +36,8 @@ static int dcssblk_open(struct inode *inode, struct file *filp); static int dcssblk_release(struct inode *inode, struct file *filp); static int dcssblk_make_request(struct request_queue *q, struct bio *bio); +static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0"; + static int dcssblk_major; static struct block_device_operations dcssblk_devops = { .owner = THIS_MODULE, @@ -76,8 +80,7 @@ struct dcssblk_dev_info { }; static struct list_head dcssblk_devices = LIST_HEAD_INIT(dcssblk_devices); -static rwlock_t dcssblk_devices_lock = RW_LOCK_UNLOCKED; - +static struct rw_semaphore dcssblk_devices_sem; /* * release function for segment device. @@ -92,8 +95,8 @@ dcssblk_release_segment(struct device *dev) /* * get a minor number. needs to be called with - * write_lock(&dcssblk_devices_lock) and the - * device needs to be enqueued before the lock is + * down_write(&dcssblk_devices_sem) and the + * device needs to be enqueued before the semaphore is * freed. */ static inline int @@ -121,7 +124,7 @@ dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info) /* * get the struct dcssblk_dev_info from dcssblk_devices * for the given name. - * read_lock(&dcssblk_devices_lock) must be held. + * down_read(&dcssblk_devices_sem) must be held. */ static struct dcssblk_dev_info * dcssblk_get_device_by_name(char *name) @@ -137,28 +140,54 @@ dcssblk_get_device_by_name(char *name) } /* - * register the device that represents a segment in sysfs, - * also add the attributes for the device + * print appropriate error message for segment_load()/segment_type() + * return code */ -static inline int -dcssblk_register_segment_device(struct device *dev) +static void +dcssblk_segment_warn(int rc, char* seg_name) { - int rc; - - rc = device_register(dev); - if (rc) - return rc; - rc = device_create_file(dev, &dev_attr_shared); - if (rc) - goto unregister_dev; - rc = device_create_file(dev, &dev_attr_save); - if (rc) - goto unregister_dev; - return rc; - -unregister_dev: - device_unregister(dev); - return rc; + switch (rc) { + case -ENOENT: + PRINT_WARN("cannot load/query segment %s, does not exist\n", + seg_name); + break; + case -ENOSYS: + PRINT_WARN("cannot load/query segment %s, not running on VM\n", + seg_name); + break; + case -EIO: + PRINT_WARN("cannot load/query segment %s, hardware error\n", + seg_name); + break; + case -ENOTSUPP: + PRINT_WARN("cannot load/query segment %s, is a multi-part " + "segment\n", seg_name); + break; + case -ENOSPC: + PRINT_WARN("cannot load/query segment %s, overlaps with " + "storage\n", seg_name); + break; + case -EBUSY: + PRINT_WARN("cannot load/query segment %s, overlaps with " + "already loaded dcss\n", seg_name); + break; + case -EPERM: + PRINT_WARN("cannot load/query segment %s, already loaded in " + "incompatible mode\n", seg_name); + break; + case -ENOMEM: + PRINT_WARN("cannot load/query segment %s, out of memory\n", + seg_name); + break; + case -ERANGE: + PRINT_WARN("cannot load/query segment %s, exceeds kernel " + "mapping range\n", seg_name); + break; + default: + PRINT_WARN("cannot load/query segment %s, return value %i\n", + seg_name, rc); + break; + } } /* @@ -184,92 +213,61 @@ dcssblk_shared_store(struct device *dev, const char *inbuf, size_t count) PRINT_WARN("Invalid value, must be 0 or 1\n"); return -EINVAL; } - write_lock(&dcssblk_devices_lock); + down_write(&dcssblk_devices_sem); dev_info = container_of(dev, struct dcssblk_dev_info, dev); if (atomic_read(&dev_info->use_count)) { PRINT_ERR("share: segment %s is busy!\n", dev_info->segment_name); - write_unlock(&dcssblk_devices_lock); - return -EBUSY; - } - if ((inbuf[0] == '1') && (dev_info->is_shared == 1)) { - PRINT_WARN("Segment %s already loaded in shared mode!\n", - dev_info->segment_name); - write_unlock(&dcssblk_devices_lock); - return count; - } - if ((inbuf[0] == '0') && (dev_info->is_shared == 0)) { - PRINT_WARN("Segment %s already loaded in exclusive mode!\n", - dev_info->segment_name); - write_unlock(&dcssblk_devices_lock); - return count; + rc = -EBUSY; + goto out; } if (inbuf[0] == '1') { // reload segment in shared mode - segment_unload(dev_info->segment_name); - rc = segment_load(dev_info->segment_name, SEGMENT_SHARED_RO, - &dev_info->start, &dev_info->end); + rc = segment_modify_shared(dev_info->segment_name, + SEGMENT_SHARED); if (rc < 0) { - PRINT_ERR("Segment %s not reloaded, rc=%d\n", - dev_info->segment_name, rc); - goto removeseg; + BUG_ON(rc == -EINVAL); + if (rc == -EIO || rc == -ENOENT) + goto removeseg; + } else { + dev_info->is_shared = 1; + switch (dev_info->segment_type) { + case SEG_TYPE_SR: + case SEG_TYPE_ER: + case SEG_TYPE_SC: + set_disk_ro(dev_info->gd,1); + } } - dev_info->is_shared = 1; - PRINT_INFO("Segment %s reloaded, shared mode.\n", - dev_info->segment_name); } else if (inbuf[0] == '0') { // reload segment in exclusive mode - segment_unload(dev_info->segment_name); - rc = segment_load(dev_info->segment_name, SEGMENT_EXCLUSIVE_RW, - &dev_info->start, &dev_info->end); + if (dev_info->segment_type == SEG_TYPE_SC) { + PRINT_ERR("Segment type SC (%s) cannot be loaded in " + "non-shared mode\n", dev_info->segment_name); + rc = -EINVAL; + goto out; + } + rc = segment_modify_shared(dev_info->segment_name, + SEGMENT_EXCLUSIVE); if (rc < 0) { - PRINT_ERR("Segment %s not reloaded, rc=%d\n", - dev_info->segment_name, rc); - goto removeseg; + BUG_ON(rc == -EINVAL); + if (rc == -EIO || rc == -ENOENT) + goto removeseg; + } else { + dev_info->is_shared = 0; + set_disk_ro(dev_info->gd, 0); } - dev_info->is_shared = 0; - PRINT_INFO("Segment %s reloaded, exclusive (read-write) mode.\n", - dev_info->segment_name); } else { - write_unlock(&dcssblk_devices_lock); PRINT_WARN("Invalid value, must be 0 or 1\n"); - return -EINVAL; + rc = -EINVAL; + goto out; } - dev_info->segment_type = rc; rc = count; - - switch (dev_info->segment_type) { - case SEGMENT_SHARED_RO: - case SEGMENT_EXCLUSIVE_RO: - set_disk_ro(dev_info->gd, 1); - break; - case SEGMENT_SHARED_RW: - case SEGMENT_EXCLUSIVE_RW: - set_disk_ro(dev_info->gd, 0); - break; - } - if ((inbuf[0] == '1') && - ((dev_info->segment_type == SEGMENT_EXCLUSIVE_RO) || - (dev_info->segment_type == SEGMENT_EXCLUSIVE_RW))) { - PRINT_WARN("Could not get shared copy of segment %s\n", - dev_info->segment_name); - rc = -EPERM; - } - if ((inbuf[0] == '0') && - ((dev_info->segment_type == SEGMENT_SHARED_RO) || - (dev_info->segment_type == SEGMENT_SHARED_RW))) { - PRINT_WARN("Could not get exclusive copy of segment %s\n", - dev_info->segment_name); - rc = -EPERM; - } - write_unlock(&dcssblk_devices_lock); goto out; removeseg: PRINT_ERR("Could not reload segment %s, removing it now!\n", dev_info->segment_name); list_del(&dev_info->lh); - write_unlock(&dcssblk_devices_lock); del_gendisk(dev_info->gd); blk_put_queue(dev_info->dcssblk_queue); @@ -278,6 +276,7 @@ removeseg: device_unregister(dev); put_device(dev); out: + up_write(&dcssblk_devices_sem); return rc; } @@ -308,13 +307,13 @@ dcssblk_save_store(struct device *dev, const char *inbuf, size_t count) } dev_info = container_of(dev, struct dcssblk_dev_info, dev); - write_lock(&dcssblk_devices_lock); + down_write(&dcssblk_devices_sem); if (inbuf[0] == '1') { if (atomic_read(&dev_info->use_count) == 0) { // device is idle => we save immediately PRINT_INFO("Saving segment %s\n", dev_info->segment_name); - segment_replace(dev_info->segment_name); + segment_save(dev_info->segment_name); } else { // device is busy => we save it when it becomes // idle in dcssblk_release @@ -332,11 +331,11 @@ dcssblk_save_store(struct device *dev, const char *inbuf, size_t count) dev_info->segment_name); } } else { - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); PRINT_WARN("Invalid value, must be 0 or 1\n"); return -EINVAL; } - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); return count; } @@ -375,9 +374,9 @@ dcssblk_add_store(struct device *dev, const char *buf, size_t count) /* * already loaded? */ - read_lock(&dcssblk_devices_lock); + down_read(&dcssblk_devices_sem); dev_info = dcssblk_get_device_by_name(local_buf); - read_unlock(&dcssblk_devices_lock); + up_read(&dcssblk_devices_sem); if (dev_info != NULL) { PRINT_WARN("Segment %s already loaded!\n", local_buf); rc = -EEXIST; @@ -412,18 +411,17 @@ dcssblk_add_store(struct device *dev, const char *buf, size_t count) /* * load the segment */ - rc = segment_load(local_buf, SEGMENT_SHARED_RO, + rc = segment_load(local_buf, SEGMENT_SHARED, &dev_info->start, &dev_info->end); if (rc < 0) { - PRINT_ERR("Segment %s not loaded, rc=%d\n", local_buf, rc); + dcssblk_segment_warn(rc, dev_info->segment_name); goto dealloc_gendisk; } seg_byte_size = (dev_info->end - dev_info->start + 1); set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors - PRINT_INFO("Loaded segment %s from %p to %p, size = %lu Byte, " - "capacity = %lu sectors (512 Byte)\n", local_buf, - (void *) dev_info->start, (void *) dev_info->end, - seg_byte_size, seg_byte_size >> 9); + PRINT_INFO("Loaded segment %s, size = %lu Byte, " + "capacity = %lu (512 Byte) sectors\n", local_buf, + seg_byte_size, seg_byte_size >> 9); dev_info->segment_type = rc; dev_info->save_pending = 0; @@ -433,10 +431,10 @@ dcssblk_add_store(struct device *dev, const char *buf, size_t count) /* * get minor, add to list */ - write_lock(&dcssblk_devices_lock); + down_write(&dcssblk_devices_sem); rc = dcssblk_assign_free_minor(dev_info); if (rc) { - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); PRINT_ERR("No free minor number available! " "Unloading segment...\n"); goto unload_seg; @@ -444,45 +442,63 @@ dcssblk_add_store(struct device *dev, const char *buf, size_t count) sprintf(dev_info->gd->disk_name, "dcssblk%d", dev_info->gd->first_minor); list_add_tail(&dev_info->lh, &dcssblk_devices); + + if (!try_module_get(THIS_MODULE)) { + rc = -ENODEV; + goto list_del; + } /* * register the device */ - rc = dcssblk_register_segment_device(&dev_info->dev); + rc = device_register(&dev_info->dev); if (rc) { PRINT_ERR("Segment %s could not be registered RC=%d\n", local_buf, rc); + module_put(THIS_MODULE); goto list_del; } - - if (!try_module_get(THIS_MODULE)) { - rc = -ENODEV; - goto list_del; - } - get_device(&dev_info->dev); + rc = device_create_file(&dev_info->dev, &dev_attr_shared); + if (rc) + goto unregister_dev; + rc = device_create_file(&dev_info->dev, &dev_attr_save); + if (rc) + goto unregister_dev; + add_disk(dev_info->gd); blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request); blk_queue_hardsect_size(dev_info->dcssblk_queue, 4096); switch (dev_info->segment_type) { - case SEGMENT_SHARED_RO: - case SEGMENT_EXCLUSIVE_RO: + case SEG_TYPE_SR: + case SEG_TYPE_ER: + case SEG_TYPE_SC: set_disk_ro(dev_info->gd,1); break; - case SEGMENT_SHARED_RW: - case SEGMENT_EXCLUSIVE_RW: + default: set_disk_ro(dev_info->gd,0); break; } PRINT_DEBUG("Segment %s loaded successfully\n", local_buf); - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); rc = count; goto out; +unregister_dev: + PRINT_ERR("device_create_file() failed!\n"); + list_del(&dev_info->lh); + blk_put_queue(dev_info->dcssblk_queue); + dev_info->gd->queue = NULL; + put_disk(dev_info->gd); + device_unregister(&dev_info->dev); + segment_unload(dev_info->segment_name); + put_device(&dev_info->dev); + up_write(&dcssblk_devices_sem); + goto out; list_del: list_del(&dev_info->lh); - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); unload_seg: segment_unload(local_buf); dealloc_gendisk: @@ -526,22 +542,21 @@ dcssblk_remove_store(struct device *dev, const char *buf, size_t count) goto out_buf; } - write_lock(&dcssblk_devices_lock); + down_write(&dcssblk_devices_sem); dev_info = dcssblk_get_device_by_name(local_buf); if (dev_info == NULL) { - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); PRINT_WARN("Segment %s is not loaded!\n", local_buf); rc = -ENODEV; goto out_buf; } if (atomic_read(&dev_info->use_count) != 0) { - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); PRINT_WARN("Segment %s is in use!\n", local_buf); rc = -EBUSY; goto out_buf; } list_del(&dev_info->lh); - write_unlock(&dcssblk_devices_lock); del_gendisk(dev_info->gd); blk_put_queue(dev_info->dcssblk_queue); @@ -552,6 +567,8 @@ dcssblk_remove_store(struct device *dev, const char *buf, size_t count) PRINT_DEBUG("Segment %s unloaded successfully\n", dev_info->segment_name); put_device(&dev_info->dev); + up_write(&dcssblk_devices_sem); + rc = count; out_buf: kfree(local_buf); @@ -587,15 +604,15 @@ dcssblk_release(struct inode *inode, struct file *filp) rc = -ENODEV; goto out; } - write_lock(&dcssblk_devices_lock); + down_write(&dcssblk_devices_sem); if (atomic_dec_and_test(&dev_info->use_count) && (dev_info->save_pending)) { PRINT_INFO("Segment %s became idle and is being saved now\n", dev_info->segment_name); - segment_replace(dev_info->segment_name); + segment_save(dev_info->segment_name); dev_info->save_pending = 0; } - write_unlock(&dcssblk_devices_lock); + up_write(&dcssblk_devices_sem); rc = 0; out: return rc; @@ -616,7 +633,7 @@ dcssblk_make_request(request_queue_t *q, struct bio *bio) dev_info = bio->bi_bdev->bd_disk->private_data; if (dev_info == NULL) goto fail; - if ((bio->bi_sector & 3) != 0 || (bio->bi_size & 4095) != 0) + if ((bio->bi_sector & 7) != 0 || (bio->bi_size & 4095) != 0) /* Request is not page-aligned. */ goto fail; if (((bio->bi_size >> 9) + bio->bi_sector) @@ -648,6 +665,47 @@ fail: return 0; } +static void +dcssblk_check_params(void) +{ + int rc, i, j, k; + char buf[9]; + struct dcssblk_dev_info *dev_info; + + for (i = 0; (i < DCSSBLK_PARM_LEN) && (dcssblk_segments[i] != '\0'); + i++) { + for (j = i; (dcssblk_segments[j] != ',') && + (dcssblk_segments[j] != '\0') && + (dcssblk_segments[j] != '(') && + (j - i) < 8; j++) + { + buf[j-i] = dcssblk_segments[j]; + } + buf[j-i] = '\0'; + rc = dcssblk_add_store(dcssblk_root_dev, buf, j-i); + if ((rc >= 0) && (dcssblk_segments[j] == '(')) { + for (k = 0; buf[k] != '\0'; k++) + buf[k] = toupper(buf[k]); + if (!strncmp(&dcssblk_segments[j], "(local)", 7)) { + down_read(&dcssblk_devices_sem); + dev_info = dcssblk_get_device_by_name(buf); + up_read(&dcssblk_devices_sem); + if (dev_info) + dcssblk_shared_store(&dev_info->dev, + "0\n", 2); + } + } + while ((dcssblk_segments[j] != ',') && + (dcssblk_segments[j] != '\0')) + { + j++; + } + if (dcssblk_segments[j] == '\0') + break; + i = j; + } +} + /* * The init/exit functions. */ @@ -695,6 +753,10 @@ dcssblk_init(void) return rc; } dcssblk_major = rc; + init_rwsem(&dcssblk_devices_sem); + + dcssblk_check_params(); + PRINT_DEBUG("...finished!\n"); return 0; } @@ -702,4 +764,12 @@ dcssblk_init(void) module_init(dcssblk_init); module_exit(dcssblk_exit); +module_param_string(segments, dcssblk_segments, DCSSBLK_PARM_LEN, 0444); +MODULE_PARM_DESC(segments, "Name of DCSS segment(s) to be loaded, " + "comma-separated list, each name max. 8 chars.\n" + "Adding \"(local)\" to segment name equals echoing 0 to " + "/sys/devices/dcssblk//shared after loading " + "the segment - \n" + "e.g. segments=\"mydcss1,mydcss2,mydcss3(local)\""); + MODULE_LICENSE("GPL");