From 95b05a7db5865855c32e0bb8b244c3a7aac1cfeb Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 25 Jan 2009 16:56:47 +0200 Subject: [PATCH] [SCSI] osd_uld: OSD scsi ULD Add a Linux driver module that registers as a SCSI ULD and probes for OSD type SCSI devices. When an OSD-type SCSI device is found a character device is created in the form of /dev/osdX - where X goes from 0 up to hard coded 64. The Major character device number used is 260. Signed-off-by: Boaz Harrosh Reviewed-by: Benny Halevy Signed-off-by: James Bottomley --- drivers/scsi/osd/Kbuild | 7 + drivers/scsi/osd/osd_uld.c | 419 +++++++++++++++++++++++++++++++++++ include/scsi/osd_initiator.h | 6 + 3 files changed, 432 insertions(+) create mode 100644 drivers/scsi/osd/osd_uld.c diff --git a/drivers/scsi/osd/Kbuild b/drivers/scsi/osd/Kbuild index a95e0251005..9d38248afcb 100644 --- a/drivers/scsi/osd/Kbuild +++ b/drivers/scsi/osd/Kbuild @@ -17,6 +17,9 @@ ifneq ($(OSD_INC),) CONFIG_SCSI_OSD_INITIATOR=m ccflags-y += -DCONFIG_SCSI_OSD_INITIATOR -DCONFIG_SCSI_OSD_INITIATOR_MODULE +CONFIG_SCSI_OSD_ULD=m +ccflags-y += -DCONFIG_SCSI_OSD_ULD -DCONFIG_SCSI_OSD_ULD_MODULE + # Uncomment to turn debug on # ccflags-y += -DCONFIG_SCSI_OSD_DEBUG @@ -30,3 +33,7 @@ endif # libosd.ko - osd-initiator library libosd-y := osd_initiator.o obj-$(CONFIG_SCSI_OSD_INITIATOR) += libosd.o + +# osd.ko - SCSI ULD and char-device +osd-y := osd_uld.o +obj-$(CONFIG_SCSI_OSD_ULD) += osd.o diff --git a/drivers/scsi/osd/osd_uld.c b/drivers/scsi/osd/osd_uld.c new file mode 100644 index 00000000000..f6f9a99adaa --- /dev/null +++ b/drivers/scsi/osd/osd_uld.c @@ -0,0 +1,419 @@ +/* + * osd_uld.c - OSD Upper Layer Driver + * + * A Linux driver module that registers as a SCSI ULD and probes + * for OSD type SCSI devices. + * It's main function is to export osd devices to in-kernel users like + * osdfs and pNFS-objects-LD. It also provides one ioctl for running + * in Kernel tests. + * + * Copyright (C) 2008 Panasas Inc. All rights reserved. + * + * Authors: + * Boaz Harrosh + * Benny Halevy + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the Panasas company nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include +#include + +#include "osd_debug.h" + +#ifndef TYPE_OSD +# define TYPE_OSD 0x11 +#endif + +#ifndef SCSI_OSD_MAJOR +# define SCSI_OSD_MAJOR 260 +#endif +#define SCSI_OSD_MAX_MINOR 64 + +static const char osd_name[] = "osd"; +static const char *osd_version_string = "open-osd 0.1.0"; +const char osd_symlink[] = "scsi_osd"; + +MODULE_AUTHOR("Boaz Harrosh "); +MODULE_DESCRIPTION("open-osd Upper-Layer-Driver osd.ko"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_CHARDEV_MAJOR(SCSI_OSD_MAJOR); +MODULE_ALIAS_SCSI_DEVICE(TYPE_OSD); + +struct osd_uld_device { + int minor; + struct kref kref; + struct cdev cdev; + struct osd_dev od; + struct gendisk *disk; + struct device *class_member; +}; + +static void __uld_get(struct osd_uld_device *oud); +static void __uld_put(struct osd_uld_device *oud); + +/* + * Char Device operations + */ + +static int osd_uld_open(struct inode *inode, struct file *file) +{ + struct osd_uld_device *oud = container_of(inode->i_cdev, + struct osd_uld_device, cdev); + + __uld_get(oud); + /* cache osd_uld_device on file handle */ + file->private_data = oud; + OSD_DEBUG("osd_uld_open %p\n", oud); + return 0; +} + +static int osd_uld_release(struct inode *inode, struct file *file) +{ + struct osd_uld_device *oud = file->private_data; + + OSD_DEBUG("osd_uld_release %p\n", file->private_data); + file->private_data = NULL; + __uld_put(oud); + return 0; +} + +/* FIXME: Only one vector for now */ +unsigned g_test_ioctl; +do_test_fn *g_do_test; + +int osduld_register_test(unsigned ioctl, do_test_fn *do_test) +{ + if (g_test_ioctl) + return -EINVAL; + + g_test_ioctl = ioctl; + g_do_test = do_test; + return 0; +} +EXPORT_SYMBOL(osduld_register_test); + +void osduld_unregister_test(unsigned ioctl) +{ + if (ioctl == g_test_ioctl) { + g_test_ioctl = 0; + g_do_test = NULL; + } +} +EXPORT_SYMBOL(osduld_unregister_test); + +static do_test_fn *_find_ioctl(unsigned cmd) +{ + if (g_test_ioctl == cmd) + return g_do_test; + else + return NULL; +} + +static long osd_uld_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct osd_uld_device *oud = file->private_data; + int ret; + do_test_fn *do_test; + + do_test = _find_ioctl(cmd); + if (do_test) + ret = do_test(&oud->od, cmd, arg); + else { + OSD_ERR("Unknown ioctl %d: osd_uld_device=%p\n", cmd, oud); + ret = -ENOIOCTLCMD; + } + return ret; +} + +static const struct file_operations osd_fops = { + .owner = THIS_MODULE, + .open = osd_uld_open, + .release = osd_uld_release, + .unlocked_ioctl = osd_uld_ioctl, +}; + +/* + * Scsi Device operations + */ + +static int __detect_osd(struct osd_uld_device *oud) +{ + struct scsi_device *scsi_device = oud->od.scsi_device; + int error; + + /* sending a test_unit_ready as first command seems to be needed + * by some targets + */ + OSD_DEBUG("start scsi_test_unit_ready %p %p %p\n", + oud, scsi_device, scsi_device->request_queue); + error = scsi_test_unit_ready(scsi_device, 10*HZ, 5, NULL); + if (error) + OSD_ERR("warning: scsi_test_unit_ready failed\n"); + + return 0; +} + +static struct class *osd_sysfs_class; +static DEFINE_IDA(osd_minor_ida); + +static int osd_probe(struct device *dev) +{ + struct scsi_device *scsi_device = to_scsi_device(dev); + struct gendisk *disk; + struct osd_uld_device *oud; + int minor; + int error; + + if (scsi_device->type != TYPE_OSD) + return -ENODEV; + + do { + if (!ida_pre_get(&osd_minor_ida, GFP_KERNEL)) + return -ENODEV; + + error = ida_get_new(&osd_minor_ida, &minor); + } while (error == -EAGAIN); + + if (error) + return error; + if (minor >= SCSI_OSD_MAX_MINOR) { + error = -EBUSY; + goto err_retract_minor; + } + + error = -ENOMEM; + oud = kzalloc(sizeof(*oud), GFP_KERNEL); + if (NULL == oud) + goto err_retract_minor; + + kref_init(&oud->kref); + dev_set_drvdata(dev, oud); + oud->minor = minor; + + /* allocate a disk and set it up */ + /* FIXME: do we need this since sg has already done that */ + disk = alloc_disk(1); + if (!disk) { + OSD_ERR("alloc_disk failed\n"); + goto err_free_osd; + } + disk->major = SCSI_OSD_MAJOR; + disk->first_minor = oud->minor; + sprintf(disk->disk_name, "osd%d", oud->minor); + oud->disk = disk; + + /* hold one more reference to the scsi_device that will get released + * in __release, in case a logout is happening while fs is mounted + */ + scsi_device_get(scsi_device); + osd_dev_init(&oud->od, scsi_device); + + /* Detect the OSD Version */ + error = __detect_osd(oud); + if (error) { + OSD_ERR("osd detection failed, non-compatible OSD device\n"); + goto err_put_disk; + } + + /* init the char-device for communication with user-mode */ + cdev_init(&oud->cdev, &osd_fops); + oud->cdev.owner = THIS_MODULE; + error = cdev_add(&oud->cdev, + MKDEV(SCSI_OSD_MAJOR, oud->minor), 1); + if (error) { + OSD_ERR("cdev_add failed\n"); + goto err_put_disk; + } + kobject_get(&oud->cdev.kobj); /* 2nd ref see osd_remove() */ + + /* class_member */ + oud->class_member = device_create(osd_sysfs_class, dev, + MKDEV(SCSI_OSD_MAJOR, oud->minor), "%s", disk->disk_name); + if (IS_ERR(oud->class_member)) { + OSD_ERR("class_device_create failed\n"); + error = PTR_ERR(oud->class_member); + goto err_put_cdev; + } + + dev_set_drvdata(oud->class_member, oud); + error = sysfs_create_link(&scsi_device->sdev_gendev.kobj, + &oud->class_member->kobj, osd_symlink); + if (error) + OSD_ERR("warning: unable to make symlink\n"); + + OSD_INFO("osd_probe %s\n", disk->disk_name); + return 0; + +err_put_cdev: + cdev_del(&oud->cdev); +err_put_disk: + scsi_device_put(scsi_device); + put_disk(disk); +err_free_osd: + dev_set_drvdata(dev, NULL); + kfree(oud); +err_retract_minor: + ida_remove(&osd_minor_ida, minor); + return error; +} + +static int osd_remove(struct device *dev) +{ + struct scsi_device *scsi_device = to_scsi_device(dev); + struct osd_uld_device *oud = dev_get_drvdata(dev); + + if (!oud || (oud->od.scsi_device != scsi_device)) { + OSD_ERR("Half cooked osd-device %p,%p || %p!=%p", + dev, oud, oud ? oud->od.scsi_device : NULL, + scsi_device); + } + + sysfs_remove_link(&oud->od.scsi_device->sdev_gendev.kobj, osd_symlink); + + if (oud->class_member) + device_destroy(osd_sysfs_class, + MKDEV(SCSI_OSD_MAJOR, oud->minor)); + + /* We have 2 references to the cdev. One is released here + * and also takes down the /dev/osdX mapping. The second + * Will be released in __remove() after all users have released + * the osd_uld_device. + */ + if (oud->cdev.owner) + cdev_del(&oud->cdev); + + __uld_put(oud); + return 0; +} + +static void __remove(struct kref *kref) +{ + struct osd_uld_device *oud = container_of(kref, + struct osd_uld_device, kref); + struct scsi_device *scsi_device = oud->od.scsi_device; + + /* now let delete the char_dev */ + kobject_put(&oud->cdev.kobj); + + osd_dev_fini(&oud->od); + scsi_device_put(scsi_device); + + OSD_INFO("osd_remove %s\n", + oud->disk ? oud->disk->disk_name : NULL); + + if (oud->disk) + put_disk(oud->disk); + + ida_remove(&osd_minor_ida, oud->minor); + kfree(oud); +} + +static void __uld_get(struct osd_uld_device *oud) +{ + kref_get(&oud->kref); +} + +static void __uld_put(struct osd_uld_device *oud) +{ + kref_put(&oud->kref, __remove); +} + +/* + * Global driver and scsi registration + */ + +static struct scsi_driver osd_driver = { + .owner = THIS_MODULE, + .gendrv = { + .name = osd_name, + .probe = osd_probe, + .remove = osd_remove, + } +}; + +static int __init osd_uld_init(void) +{ + int err; + + osd_sysfs_class = class_create(THIS_MODULE, osd_symlink); + if (IS_ERR(osd_sysfs_class)) { + OSD_ERR("Unable to register sysfs class => %ld\n", + PTR_ERR(osd_sysfs_class)); + return PTR_ERR(osd_sysfs_class); + } + + err = register_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0), + SCSI_OSD_MAX_MINOR, osd_name); + if (err) { + OSD_ERR("Unable to register major %d for osd ULD => %d\n", + SCSI_OSD_MAJOR, err); + goto err_out; + } + + err = scsi_register_driver(&osd_driver.gendrv); + if (err) { + OSD_ERR("scsi_register_driver failed => %d\n", err); + goto err_out_chrdev; + } + + OSD_INFO("LOADED %s\n", osd_version_string); + return 0; + +err_out_chrdev: + unregister_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0), SCSI_OSD_MAX_MINOR); +err_out: + class_destroy(osd_sysfs_class); + return err; +} + +static void __exit osd_uld_exit(void) +{ + scsi_unregister_driver(&osd_driver.gendrv); + unregister_chrdev_region(MKDEV(SCSI_OSD_MAJOR, 0), SCSI_OSD_MAX_MINOR); + class_destroy(osd_sysfs_class); + OSD_INFO("UNLOADED %s\n", osd_version_string); +} + +module_init(osd_uld_init); +module_exit(osd_uld_exit); diff --git a/include/scsi/osd_initiator.h b/include/scsi/osd_initiator.h index 1d92247f820..a5dbbddcf73 100644 --- a/include/scsi/osd_initiator.h +++ b/include/scsi/osd_initiator.h @@ -33,6 +33,12 @@ struct osd_dev { unsigned def_timeout; }; +/* Add/remove test ioctls from external modules */ +typedef int (do_test_fn)(struct osd_dev *od, unsigned cmd, unsigned long arg); +int osduld_register_test(unsigned ioctl, do_test_fn *do_test); +void osduld_unregister_test(unsigned ioctl); + +/* These are called by uld at probe time */ void osd_dev_init(struct osd_dev *od, struct scsi_device *scsi_device); void osd_dev_fini(struct osd_dev *od);