From 6c3633d08acf514e2e89aa95d2346ce9d64d719a Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Wed, 24 Aug 2011 10:51:15 +0200 Subject: [PATCH] [SCSI] scsi_dh: Implement match callback function Some device handler types are not tied to the vendor/model but rather to a specific capability. Eg ALUA is supported if the 'TPGS' setting in the standard inquiry is set. This patch implements a 'match' callback for device handler which supersedes the original vendor/model lookup and implements the callback for the ALUA handler. Signed-off-by: Hannes Reinecke Signed-off-by: James Bottomley --- drivers/scsi/device_handler/scsi_dh.c | 53 ++++++++++++++++++++++++++---- drivers/scsi/device_handler/scsi_dh_alua.c | 23 +++---------- include/scsi/scsi_device.h | 1 + 3 files changed, 52 insertions(+), 25 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c index fccd0f6..3ac71cf 100644 --- a/drivers/scsi/device_handler/scsi_dh.c +++ b/drivers/scsi/device_handler/scsi_dh.c @@ -60,6 +60,46 @@ static struct scsi_device_handler *get_device_handler_by_idx(int idx) } /* + * device_handler_match_function - Match a device handler to a device + * @sdev - SCSI device to be tested + * + * Tests @sdev against the match function of all registered device_handler. + * Returns the found device handler or NULL if not found. + */ +static struct scsi_device_handler * +device_handler_match_function(struct scsi_device *sdev) +{ + struct scsi_device_handler *tmp_dh, *found_dh = NULL; + + spin_lock(&list_lock); + list_for_each_entry(tmp_dh, &scsi_dh_list, list) { + if (tmp_dh->match && tmp_dh->match(sdev)) { + found_dh = tmp_dh; + break; + } + } + spin_unlock(&list_lock); + return found_dh; +} + +/* + * device_handler_match_devlist - Match a device handler to a device + * @sdev - SCSI device to be tested + * + * Tests @sdev against all device_handler registered in the devlist. + * Returns the found device handler or NULL if not found. + */ +static struct scsi_device_handler * +device_handler_match_devlist(struct scsi_device *sdev) +{ + int idx; + + idx = scsi_get_device_flags_keyed(sdev, sdev->vendor, sdev->model, + SCSI_DEVINFO_DH); + return get_device_handler_by_idx(idx); +} + +/* * device_handler_match - Attach a device handler to a device * @scsi_dh - The device handler to match against or NULL * @sdev - SCSI device to be tested against @scsi_dh @@ -72,12 +112,11 @@ static struct scsi_device_handler * device_handler_match(struct scsi_device_handler *scsi_dh, struct scsi_device *sdev) { - struct scsi_device_handler *found_dh = NULL; - int idx; + struct scsi_device_handler *found_dh; - idx = scsi_get_device_flags_keyed(sdev, sdev->vendor, sdev->model, - SCSI_DEVINFO_DH); - found_dh = get_device_handler_by_idx(idx); + found_dh = device_handler_match_function(sdev); + if (!found_dh) + found_dh = device_handler_match_devlist(sdev); if (scsi_dh && found_dh != scsi_dh) found_dh = NULL; @@ -327,7 +366,7 @@ int scsi_register_device_handler(struct scsi_device_handler *scsi_dh) list_add(&scsi_dh->list, &scsi_dh_list); spin_unlock(&list_lock); - for (i = 0; scsi_dh->devlist[i].vendor; i++) { + for (i = 0; scsi_dh->devlist && scsi_dh->devlist[i].vendor; i++) { scsi_dev_info_list_add_keyed(0, scsi_dh->devlist[i].vendor, scsi_dh->devlist[i].model, @@ -360,7 +399,7 @@ int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh) bus_for_each_dev(&scsi_bus_type, NULL, scsi_dh, scsi_dh_notifier_remove); - for (i = 0; scsi_dh->devlist[i].vendor; i++) { + for (i = 0; scsi_dh->devlist && scsi_dh->devlist[i].vendor; i++) { scsi_dev_info_list_del_keyed(scsi_dh->devlist[i].vendor, scsi_dh->devlist[i].model, SCSI_DEVINFO_DH); diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 4326778..80c5cf3 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -677,23 +677,10 @@ static int alua_prep_fn(struct scsi_device *sdev, struct request *req) } -static const struct scsi_dh_devlist alua_dev_list[] = { - {"HP", "MSA VOLUME" }, - {"HP", "HSV101" }, - {"HP", "HSV111" }, - {"HP", "HSV200" }, - {"HP", "HSV210" }, - {"HP", "HSV300" }, - {"IBM", "2107900" }, - {"IBM", "2145" }, - {"Pillar", "Axiom" }, - {"Intel", "Multi-Flex"}, - {"NETAPP", "LUN"}, - {"NETAPP", "LUN C-Mode"}, - {"AIX", "NVDISK"}, - {"Promise", "VTrak"}, - {NULL, NULL} -}; +static bool alua_match(struct scsi_device *sdev) +{ + return (scsi_device_tpgs(sdev) != 0); +} static int alua_bus_attach(struct scsi_device *sdev); static void alua_bus_detach(struct scsi_device *sdev); @@ -701,12 +688,12 @@ static void alua_bus_detach(struct scsi_device *sdev); static struct scsi_device_handler alua_dh = { .name = ALUA_DH_NAME, .module = THIS_MODULE, - .devlist = alua_dev_list, .attach = alua_bus_attach, .detach = alua_bus_detach, .prep_fn = alua_prep_fn, .check_sense = alua_check_sense, .activate = alua_activate, + .match = alua_match, }; /* diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index f751d37..5591ed5 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -197,6 +197,7 @@ struct scsi_device_handler { int (*activate)(struct scsi_device *, activate_complete, void *); int (*prep_fn)(struct scsi_device *, struct request *); int (*set_params)(struct scsi_device *, const char *); + bool (*match)(struct scsi_device *); }; struct scsi_dh_data { -- 2.7.4