From 95b05a7db5865855c32e0bb8b244c3a7aac1cfeb Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 25 Jan 2009 16:56:47 +0200 Subject: [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/osd_uld.c | 419 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 419 insertions(+) create mode 100644 drivers/scsi/osd/osd_uld.c (limited to 'drivers/scsi/osd/osd_uld.c') 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); -- cgit v1.2.3 From b799bc7da0ce5ba4a988c521a8fb10452eb419f0 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 25 Jan 2009 16:58:03 +0200 Subject: [SCSI] osd_uld: API for retrieving osd devices from Kernel Kernel clients like exofs can retrieve struct osd_dev(s) by means of below API. + osduld_path_lookup() - given a path (e.g "/dev/osd0") locks and returns the corresponding struct osd_dev, which is then needed for subsequent libosd use. + osduld_put_device() - free up use of an osd_dev. Devices can be shared by multiple clients. The osd_uld_device's life time is governed by an embedded kref structure. The osd_uld_device holds an extra reference to both it's char-device and it's scsi_device, and will release these just before the final deallocation. There are three possible lock sources of the osd_uld_device 1. First and for most is the probe() function called by scsi-ml upon a successful login into a target. Released in release() when logout. 2. Second by user-mode file handles opened on the char-dev. 3. Third is here by Kernel users. All three locks must be removed before the osd_uld_device is freed. The MODULE has three lock sources as well: 1. scsi-ml at probe() time, removed after release(). (login/logout) 2. The user-mode file handles open/close. 3. Import symbols by client modules like exofs. TODO: This API is not enough for the pNFS-objects LD. A more versatile API will be needed. Proposed API could be: struct osd_dev *osduld_sysid_lookup(const char id[OSD_SYSTEMID_LEN]); Signed-off-by: Boaz Harrosh Signed-off-by: James Bottomley --- drivers/scsi/osd/osd_uld.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) (limited to 'drivers/scsi/osd/osd_uld.c') diff --git a/drivers/scsi/osd/osd_uld.c b/drivers/scsi/osd/osd_uld.c index f6f9a99adaa..cd4ca7cd9f7 100644 --- a/drivers/scsi/osd/osd_uld.c +++ b/drivers/scsi/osd/osd_uld.c @@ -173,6 +173,69 @@ static const struct file_operations osd_fops = { .unlocked_ioctl = osd_uld_ioctl, }; +struct osd_dev *osduld_path_lookup(const char *path) +{ + struct nameidata nd; + struct inode *inode; + struct cdev *cdev; + struct osd_uld_device *uninitialized_var(oud); + int error; + + if (!path || !*path) { + OSD_ERR("Mount with !path || !*path\n"); + return ERR_PTR(-EINVAL); + } + + error = path_lookup(path, LOOKUP_FOLLOW, &nd); + if (error) { + OSD_ERR("path_lookup of %s faild=>%d\n", path, error); + return ERR_PTR(error); + } + + inode = nd.path.dentry->d_inode; + error = -EINVAL; /* Not the right device e.g osd_uld_device */ + if (!S_ISCHR(inode->i_mode)) { + OSD_DEBUG("!S_ISCHR()\n"); + goto out; + } + + cdev = inode->i_cdev; + if (!cdev) { + OSD_ERR("Before mounting an OSD Based filesystem\n"); + OSD_ERR(" user-mode must open+close the %s device\n", path); + OSD_ERR(" Example: bash: echo < %s\n", path); + goto out; + } + + /* The Magic wand. Is it our char-dev */ + /* TODO: Support sg devices */ + if (cdev->owner != THIS_MODULE) { + OSD_ERR("Error mounting %s - is not an OSD device\n", path); + goto out; + } + + oud = container_of(cdev, struct osd_uld_device, cdev); + + __uld_get(oud); + error = 0; + +out: + path_put(&nd.path); + return error ? ERR_PTR(error) : &oud->od; +} +EXPORT_SYMBOL(osduld_path_lookup); + +void osduld_put_device(struct osd_dev *od) +{ + if (od) { + struct osd_uld_device *oud = container_of(od, + struct osd_uld_device, od); + + __uld_put(oud); + } +} +EXPORT_SYMBOL(osduld_put_device); + /* * Scsi Device operations */ -- cgit v1.2.3 From 1b9dce94c8a24a3f1a01fcdf688f2d903b32acdf Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 25 Jan 2009 17:13:38 +0200 Subject: [SCSI] libosd: OSDv2 auto detection Auto detect an OSDv2 or OSDv1 target at run time. Note how none of the OSD API calls change. The tests do not know what device version it is. This test now passes against both the IBM-OSD-SIM OSD1 target as well as OSC's OSD2 target. Signed-off-by: Boaz Harrosh Reviewed-by: Benny Halevy Signed-off-by: James Bottomley --- drivers/scsi/osd/osd_uld.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/scsi/osd/osd_uld.c') diff --git a/drivers/scsi/osd/osd_uld.c b/drivers/scsi/osd/osd_uld.c index cd4ca7cd9f7..f8b1a749958 100644 --- a/drivers/scsi/osd/osd_uld.c +++ b/drivers/scsi/osd/osd_uld.c @@ -243,6 +243,7 @@ EXPORT_SYMBOL(osduld_put_device); static int __detect_osd(struct osd_uld_device *oud) { struct scsi_device *scsi_device = oud->od.scsi_device; + char caps[OSD_CAP_LEN]; int error; /* sending a test_unit_ready as first command seems to be needed @@ -254,6 +255,10 @@ static int __detect_osd(struct osd_uld_device *oud) if (error) OSD_ERR("warning: scsi_test_unit_ready failed\n"); + osd_sec_init_nosec_doall_caps(caps, &osd_root_object, false, true); + if (osd_auto_detect_ver(&oud->od, caps)) + return -ENODEV; + return 0; } -- cgit v1.2.3