From 2cdd6410e5a1665823f2a048fc7f8f6a8384be1d Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 29 Nov 2009 16:26:45 +0200 Subject: [SCSI] libosd: osd_dev_info: Unique Identification of an OSD device Define an osd_dev_info structure that Uniquely identifies an OSD device lun on the network. The identification is built from unique target attributes and is the same for all network/SAN machines. osduld_info_lookup() - NEW New API that will lookup an osd_dev by its osd_dev_info. This is used by pNFS-objects for cross network global device identification. And by exofs multy-device support, the device info is specified in the on-disk exofs device table. osduld_device_info() - NEW Given an osd_dev handle returns its associated osd_dev_info. The ULD fetches this information at startup and hangs it on each OSD device. (This is a fast operation that can be called at any condition) osduld_device_same() - NEW With a given osd_dev at one hand and an osd_dev_info at another, we would like to know if they are the same device. Two osd_dev handles can be checked by: osduld_device_same(od1, osduld_device_info(od2)); osd_auto_detect_ver() - REVISED Now returns an osd_dev_info structure. Is only called once by ULD as before. See added comments for how to use. Signed-off-by: Boaz Harrosh Signed-off-by: James Bottomley --- drivers/scsi/osd/osd_initiator.c | 26 +++++++--- drivers/scsi/osd/osd_uld.c | 100 +++++++++++++++++++++++++++++++++++++-- 2 files changed, 117 insertions(+), 9 deletions(-) (limited to 'drivers/scsi/osd') diff --git a/drivers/scsi/osd/osd_initiator.c b/drivers/scsi/osd/osd_initiator.c index 7a117c18114c..60b7ca1e9bc0 100644 --- a/drivers/scsi/osd/osd_initiator.c +++ b/drivers/scsi/osd/osd_initiator.c @@ -73,7 +73,8 @@ static const char *_osd_ver_desc(struct osd_request *or) #define ATTR_DEF_RI(id, len) ATTR_DEF(OSD_APAGE_ROOT_INFORMATION, id, len) -static int _osd_print_system_info(struct osd_dev *od, void *caps) +static int _osd_get_print_system_info(struct osd_dev *od, + void *caps, struct osd_dev_info *odi) { struct osd_request *or; struct osd_attr get_attrs[] = { @@ -137,8 +138,12 @@ static int _osd_print_system_info(struct osd_dev *od, void *caps) OSD_INFO("PRODUCT_SERIAL_NUMBER [%s]\n", (char *)pFirst); - pFirst = get_attrs[a].val_ptr; - OSD_INFO("OSD_NAME [%s]\n", (char *)pFirst); + odi->osdname_len = get_attrs[a].len; + /* Avoid NULL for memcmp optimization 0-length is good enough */ + odi->osdname = kzalloc(odi->osdname_len + 1, GFP_KERNEL); + if (odi->osdname_len) + memcpy(odi->osdname, get_attrs[a].val_ptr, odi->osdname_len); + OSD_INFO("OSD_NAME [%s]\n", odi->osdname); a++; pFirst = get_attrs[a++].val_ptr; @@ -171,6 +176,14 @@ static int _osd_print_system_info(struct osd_dev *od, void *caps) sid_dump, sizeof(sid_dump), true); OSD_INFO("OSD_SYSTEM_ID(%d)\n" " [%s]\n", len, sid_dump); + + if (unlikely(len > sizeof(odi->systemid))) { + OSD_ERR("OSD Target error: OSD_SYSTEM_ID too long(%d). " + "device idetification might not work\n", len); + len = sizeof(odi->systemid); + } + odi->systemid_len = len; + memcpy(odi->systemid, get_attrs[a].val_ptr, len); a++; } out: @@ -178,16 +191,17 @@ out: return ret; } -int osd_auto_detect_ver(struct osd_dev *od, void *caps) +int osd_auto_detect_ver(struct osd_dev *od, + void *caps, struct osd_dev_info *odi) { int ret; /* Auto-detect the osd version */ - ret = _osd_print_system_info(od, caps); + ret = _osd_get_print_system_info(od, caps, odi); if (ret) { osd_dev_set_ver(od, OSD_VER1); OSD_DEBUG("converting to OSD1\n"); - ret = _osd_print_system_info(od, caps); + ret = _osd_get_print_system_info(od, caps, odi); } return ret; diff --git a/drivers/scsi/osd/osd_uld.c b/drivers/scsi/osd/osd_uld.c index fc6fc1c4d4d1..0a90702b3d71 100644 --- a/drivers/scsi/osd/osd_uld.c +++ b/drivers/scsi/osd/osd_uld.c @@ -84,6 +84,7 @@ struct osd_uld_device { struct device class_dev; struct cdev cdev; struct osd_dev od; + struct osd_dev_info odi; struct gendisk *disk; }; @@ -225,6 +226,72 @@ free_od: } EXPORT_SYMBOL(osduld_path_lookup); +static inline bool _the_same_or_null(const u8 *a1, unsigned a1_len, + const u8 *a2, unsigned a2_len) +{ + if (!a2_len) /* User string is Empty means don't care */ + return true; + + if (a1_len != a2_len) + return false; + + return 0 == memcmp(a1, a2, a1_len); +} + +struct find_oud_t { + const struct osd_dev_info *odi; + struct device *dev; + struct osd_uld_device *oud; +} ; + +int _mach_odi(struct device *dev, void *find_data) +{ + struct osd_uld_device *oud = container_of(dev, struct osd_uld_device, + class_dev); + struct find_oud_t *fot = find_data; + const struct osd_dev_info *odi = fot->odi; + + if (_the_same_or_null(oud->odi.systemid, oud->odi.systemid_len, + odi->systemid, odi->systemid_len) && + _the_same_or_null(oud->odi.osdname, oud->odi.osdname_len, + odi->osdname, odi->osdname_len)) { + OSD_DEBUG("found device sysid_len=%d osdname=%d\n", + odi->systemid_len, odi->osdname_len); + fot->oud = oud; + return 1; + } else { + return 0; + } +} + +/* osduld_info_lookup - Loop through all devices, return the requested osd_dev. + * + * if @odi->systemid_len and/or @odi->osdname_len are zero, they act as a don't + * care. .e.g if they're both zero /dev/osd0 is returned. + */ +struct osd_dev *osduld_info_lookup(const struct osd_dev_info *odi) +{ + struct find_oud_t find = {.odi = odi}; + + find.dev = class_find_device(&osd_uld_class, NULL, &find, _mach_odi); + if (likely(find.dev)) { + struct osd_dev_handle *odh = kzalloc(sizeof(*odh), GFP_KERNEL); + + if (unlikely(!odh)) { + put_device(find.dev); + return ERR_PTR(-ENOMEM); + } + + odh->od = find.oud->od; + odh->oud = find.oud; + + return &odh->od; + } + + return ERR_PTR(-ENODEV); +} +EXPORT_SYMBOL(osduld_info_lookup); + void osduld_put_device(struct osd_dev *od) { if (od && !IS_ERR(od)) { @@ -240,14 +307,39 @@ void osduld_put_device(struct osd_dev *od) * is called after the fops->release. A get_/put_ pair makes * sure we have a cdev for the duration of fput */ - get_device(&oud->class_dev); - fput(odh->file); + if (odh->file) { + get_device(&oud->class_dev); + fput(odh->file); + } put_device(&oud->class_dev); kfree(odh); } } EXPORT_SYMBOL(osduld_put_device); +const struct osd_dev_info *osduld_device_info(struct osd_dev *od) +{ + struct osd_dev_handle *odh = + container_of(od, struct osd_dev_handle, od); + return &odh->oud->odi; +} +EXPORT_SYMBOL(osduld_device_info); + +bool osduld_device_same(struct osd_dev *od, const struct osd_dev_info *odi) +{ + struct osd_dev_handle *odh = + container_of(od, struct osd_dev_handle, od); + struct osd_uld_device *oud = odh->oud; + + return (oud->odi.systemid_len == odi->systemid_len) && + _the_same_or_null(oud->odi.systemid, oud->odi.systemid_len, + odi->systemid, odi->systemid_len) && + (oud->odi.osdname_len == odi->osdname_len) && + _the_same_or_null(oud->odi.osdname, oud->odi.osdname_len, + odi->osdname, odi->osdname_len); +} +EXPORT_SYMBOL(osduld_device_same); + /* * Scsi Device operations */ @@ -268,7 +360,7 @@ static int __detect_osd(struct osd_uld_device *oud) 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)) + if (osd_auto_detect_ver(&oud->od, caps, &oud->odi)) return -ENODEV; return 0; @@ -280,6 +372,8 @@ static void __remove(struct device *dev) class_dev); struct scsi_device *scsi_device = oud->od.scsi_device; + kfree(oud->odi.osdname); + if (oud->cdev.owner) cdev_del(&oud->cdev); -- cgit v1.2.3