[v2,1/8] scsi: Add ufs transport class

Message ID	1533469196-300-2-git-send-email-avri.altman@wdc.com (mailing list archive)
State	Changes Requested
Headers	show Return-Path: <linux-scsi-owner@kernel.org> From: Avri Altman <avri.altman@wdc.com> To: Christoph Hellwig <hch@lst.de>, Johannes Thumshirn <jthumshirn@suse.de>, Hannes Reinecke <hare@suse.com>, Bart Van Assche <Bart.VanAssche@wdc.com>, "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>, "Martin K. Petersen" <martin.petersen@oracle.com>, linux-scsi@vger.kernel.org Cc: Stanislav Nijnikov <stanislav.nijnikov@wdc.com>, Avi Shchislowski <avi.shchislowski@wdc.com>, Alex Lemberg <alex.lemberg@wdc.com>, Subhash Jadavani <subhashj@codeaurora.org>, Vinayak Holikatti <Vinayak.Holikatti@wdc.com>, Avri Altman <avri.altman@wdc.com> Subject: [PATCH v2 1/8] scsi: Add ufs transport class Date: Sun, 5 Aug 2018 14:39:49 +0300 Message-Id: <1533469196-300-2-git-send-email-avri.altman@wdc.com> In-Reply-To: <1533469196-300-1-git-send-email-avri.altman@wdc.com> References: <1533469196-300-1-git-send-email-avri.altman@wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk
Series	scsi: scsi transport for ufs devices \| expand [v2,0/8] scsi: scsi transport for ufs devices [v2,1/8] scsi: Add ufs transport class [v2,2/8] scsi: ufs: Add ufs-bsg module [v2,3/8] scsi: ufs: Instantiate a ufs transport if its available [v2,4/8] scsi: ufs: Add fill task management request [v2,5/8] scsi: ufs: Allow ufshcd_issue_tm_cmd accept raw task upius [v2,6/8] scsi: ufs: Add API to execute raw upiu commands [v2,7/8] scsi: ufs-bsg: Add support for raw upiu in ufs_bsg_request() [v2,8/8] scsi: ufs-bsg: Add support for uic commands in ufs_bsg_request()

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig index 8fc851a..9e99275 100644 --- a/drivers/scsi/Kconfig +++ b/drivers/scsi/Kconfig @@ -290,6 +290,19 @@ config SCSI_SAS_ATTRS If you wish to export transport-specific information about each attached SAS device to sysfs, say Y. +config SCSI_UFS_ATTRS + tristate "UFS Transport Attributes" + depends on SCSI + select BLK_DEV_BSGLIB + help + Scsi transport is a framework that allow to send scsi commands to + a non-scsi devices. Still, it is flexible enough to allow sending + non-scsi commands as well. We will use this framework to manage + ufs devices by sending UPIU transactions. + + If you wish to export transport-specific information about + each attached UFS device to sysfs, say Y. + source "drivers/scsi/libsas/Kconfig" config SCSI_SRP_ATTRS diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile index d1bad43..e0efc06 100644 --- a/drivers/scsi/Makefile +++ b/drivers/scsi/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_SCSI_ISCSI_ATTRS) += scsi_transport_iscsi.o obj-$(CONFIG_SCSI_SAS_ATTRS) += scsi_transport_sas.o obj-$(CONFIG_SCSI_SAS_LIBSAS) += libsas/ obj-$(CONFIG_SCSI_SRP_ATTRS) += scsi_transport_srp.o +obj-$(CONFIG_SCSI_UFS_ATTRS) += scsi_transport_ufs.o obj-$(CONFIG_SCSI_DH) += device_handler/ obj-$(CONFIG_LIBFC) += libfc/ diff --git a/drivers/scsi/scsi_transport_ufs.c b/drivers/scsi/scsi_transport_ufs.c new file mode 100644 index 0000000..06349c6 --- /dev/null +++ b/drivers/scsi/scsi_transport_ufs.c @@ -0,0 +1,354 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SCSI UFS transport class + * + * Copyright (C) 2018 Western Digital Corporation + */ + + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/blkdev.h> + +#include <scsi/scsi_device.h> +#include <scsi/scsi_transport.h> +#include <scsi/scsi_transport_ufs.h> + + +#define UFS_HOST_ATTRS 0 +#define UFS_PORT_ATTRS 0 + +#define MAX_PORTS 256 +static DEFINE_IDA(ufs_ida); + +struct ufs_internal { + struct scsi_transport_template t; + struct ufs_function_template *f; + + struct device_attribute *host_attrs[UFS_HOST_ATTRS + 1]; + struct device_attribute *port_attrs[UFS_PORT_ATTRS + 1]; + struct transport_container port_attr_cont; +}; + +static inline struct ufs_internal * +to_ufs_internal(struct scsi_transport_template *tmpl) +{ + return container_of(tmpl, struct ufs_internal, t); +} + +struct ufs_host_attrs { + atomic_t active_ports; +}; + +static inline struct ufs_host_attrs * +to_ufs_host_attrs(struct Scsi_Host *shost) +{ + return (struct ufs_host_attrs *)shost->shost_data; +} + +static int ufs_bsg_dispatch(struct bsg_job *job) +{ + struct Scsi_Host *shost = dev_to_shost(job->dev); + struct ufs_internal *i = to_ufs_internal(shost->transportt); + + /* check for payload_len when we'll support data transfer upiu */ + + return i->f->bsg_request(job); +} + +static int ufs_bsg_initialize(struct Scsi_Host *shost, struct ufs_port *port) +{ + struct request_queue *q; + struct ufs_internal *i = to_ufs_internal(shost->transportt); + + if (!i->f->bsg_request) { + pr_info("%s can't handle ufs requests\n", shost->hostt->name); + return 0; + } + + q = bsg_setup_queue(&port->dev, dev_name(&port->dev), + ufs_bsg_dispatch, 0); + if (IS_ERR(q)) + return PTR_ERR(q); + port->q = q; + + return 0; +} + +static int ufs_host_setup(struct transport_container *tc, struct device *dev, + struct device *cdev) +{ + struct Scsi_Host *shost = dev_to_shost(dev); + struct ufs_host_attrs *ufs_host = to_ufs_host_attrs(shost); + + atomic_set(&ufs_host->active_ports, 0); + + return 0; +} + +static DECLARE_TRANSPORT_CLASS(ufs_host_class, "ufs_host", ufs_host_setup, + NULL, NULL); + +static DECLARE_TRANSPORT_CLASS(ufs_port_class, "ufs_ports", + NULL, NULL, NULL); + +static int ufs_host_match(struct attribute_container *cont, + struct device *dev) +{ + struct Scsi_Host *shost; + struct ufs_internal *i; + + if (!scsi_is_host_device(dev)) + return 0; + + shost = dev_to_shost(dev); + if (!shost->transportt) + return 0; + + if (shost->transportt->host_attrs.ac.class != &ufs_host_class.class) + return 0; + + i = to_ufs_internal(shost->transportt); + + return &i->t.host_attrs.ac == cont; +} + +static void ufs_port_release(struct device *dev) +{ + struct ufs_port *port = dev_to_ufs_port(dev); + struct Scsi_Host *shost = dev_to_shost(dev->parent); + struct ufs_host_attrs *ufs_host = to_ufs_host_attrs(shost); + + ida_simple_remove(&ufs_ida, port->id); + atomic_dec(&ufs_host->active_ports); + put_device(dev->parent); + kfree(port); +} + +static inline int scsi_is_ufs_port(const struct device *dev) +{ + return dev->release == ufs_port_release; +} + +static int ufs_port_match(struct attribute_container *cont, struct device *dev) +{ + struct Scsi_Host *shost; + struct ufs_internal *i; + + if (!scsi_is_ufs_port(dev)) + return 0; + + shost = dev_to_shost(dev->parent); + + if (!shost->transportt) + return 0; + + if (shost->transportt->host_attrs.ac.class != &ufs_host_class.class) + return 0; + + i = to_ufs_internal(shost->transportt); + return &i->port_attr_cont.ac == cont; +} + +/** + * ufs_attach_transport - instantiate UFS transport template + * @ft: UFS transport class function template + */ +struct scsi_transport_template * +ufs_attach_transport(struct ufs_function_template *ft) +{ + struct ufs_internal *i = kzalloc(sizeof(struct ufs_internal), + GFP_KERNEL); + + if (unlikely(!i)) + return NULL; + + i->f = ft; + i->t.host_attrs.ac.attrs = &i->host_attrs[0]; + i->t.host_attrs.ac.class = &ufs_host_class.class; + i->t.host_attrs.ac.match = ufs_host_match; + i->t.host_size = sizeof(struct ufs_host_attrs); + i->host_attrs[0] = NULL; + transport_container_register(&i->t.host_attrs); + + i->port_attr_cont.ac.class = &ufs_port_class.class; + i->port_attr_cont.ac.attrs = &i->port_attrs[0]; + i->port_attr_cont.ac.match = ufs_port_match; + i->port_attrs[0] = NULL; + transport_container_register(&i->port_attr_cont); + + return &i->t; +} +EXPORT_SYMBOL(ufs_attach_transport); + +/** + * ufs_release_transport - release UFS transport template instance + * @t: transport template instance + */ +void ufs_release_transport(struct scsi_transport_template *t) +{ + struct ufs_internal *i = to_ufs_internal(t); + + transport_container_unregister(&i->t.host_attrs); + transport_container_unregister(&i->port_attr_cont); + kfree(i); +} +EXPORT_SYMBOL(ufs_release_transport); + +/** ufs_port_alloc - allocate and initialize a UFS port structure + * @shost: scsi host that the port is attached to + * + * Allocates a UFS port structure. It will be added to the device tree + * below the device specified by its Scsi_Host parent. + * Returns %NULL on error + */ +struct ufs_port *ufs_port_alloc(struct Scsi_Host *shost) +{ + struct ufs_port *port; + struct device *parent = &shost->shost_gendev; + struct ufs_host_attrs *ufs_host = to_ufs_host_attrs(shost); + + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!port) + return NULL; + + port->id = ida_simple_get(&ufs_ida, 0, MAX_PORTS, GFP_KERNEL); + if (port->id < 0) + return NULL; + atomic_inc(&ufs_host->active_ports); + + device_initialize(&port->dev); + + port->dev.parent = get_device(parent); + port->dev.release = ufs_port_release; + + dev_set_name(&port->dev, "ufs-port-%d:%d", shost->host_no, port->id); + + transport_setup_device(&port->dev); + + return port; +} +EXPORT_SYMBOL(ufs_port_alloc); + +/** + * ufs_port_add - add a UFS port to the device hierarchy + * @port: port to be added + * + * publishes a port to the rest of the system + */ +int ufs_port_add(struct ufs_port *port) +{ + struct device *dev = &port->dev; + struct Scsi_Host *shost = dev_to_shost(dev->parent); + int error; + + if (!port) { + pr_err("%s failed with null port\n", __func__); + return -EINVAL; + } + + error = device_add(dev); + + if (error) + return error; + + transport_add_device(dev); + transport_configure_device(dev); + + if (ufs_bsg_initialize(shost, port)) + dev_err(dev, "fail to initialize a bsg dev %d\n", + shost->host_no); + + return 0; +} +EXPORT_SYMBOL(ufs_port_add); + +/** + * ufs_port_free - free a ufs port + * @port: ufs port to free + * + * Frees the specified ufs port. Should be called on ufs_port_add() failure. + */ +void ufs_port_free(struct ufs_port *port) +{ + transport_destroy_device(&port->dev); + put_device(&port->dev); +} +EXPORT_SYMBOL(ufs_port_free); + +/** + * ufs_port_delete - remove a ufs port + * @port: ufs port to remove + * + */ +void ufs_port_delete(struct ufs_port *port) +{ + struct device *dev = &port->dev; + + if (port->q) + bsg_unregister_queue(port->q); + + transport_remove_device(dev); + device_del(dev); + transport_destroy_device(dev); + + put_device(dev); +} +EXPORT_SYMBOL(ufs_port_delete); + +static int do_ufs_port_del(struct device *dev, void *data) +{ + if (scsi_is_ufs_port(dev)) + ufs_port_delete(dev_to_ufs_port(dev)); + + return 0; +} + +/** + * ufs_remove_host - tear down a ufs port devices + * @shost: the scsi host which is parenting the ufs port objects + * + * Removes all ufs port devices. + * Unharm Other devices that are attached to that host. + */ +void ufs_remove_host(struct Scsi_Host *shost) +{ + device_for_each_child(&shost->shost_gendev, NULL, do_ufs_port_del); +} +EXPORT_SYMBOL_GPL(ufs_remove_host); + +static __init int ufs_transport_init(void) +{ + int error; + + error = transport_class_register(&ufs_host_class); + if (error) + goto out; + + error = transport_class_register(&ufs_port_class); + if (error) + goto out_unregister_transport; + + return 0; + +out_unregister_transport: + transport_class_unregister(&ufs_host_class); +out: + return error; +} + +static void __exit ufs_transport_exit(void) +{ + transport_class_unregister(&ufs_host_class); + transport_class_unregister(&ufs_port_class); +} + +MODULE_AUTHOR("WDC"); +MODULE_DESCRIPTION("UFS Transport Attributes"); +MODULE_LICENSE("GPL"); + +module_init(ufs_transport_init); +module_exit(ufs_transport_exit); diff --git a/include/scsi/scsi_transport_ufs.h b/include/scsi/scsi_transport_ufs.h new file mode 100644 index 0000000..c45dfb8 --- /dev/null +++ b/include/scsi/scsi_transport_ufs.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2018 Western Digital Corporation + */ + +#ifndef SCSI_TRANSPORT_UFS_H +#define SCSI_TRANSPORT_UFS_H + +#include <linux/bsg-lib.h> +#include <linux/bsg.h> +#include <scsi/scsi.h> +#include <scsi/scsi_host.h> + + +struct ufs_function_template { + int (*bsg_request)(struct bsg_job *job); +}; + +/* One might expect a more complex structure – + * some representation of a list containing all the luns of the systems, + * including the w-luns. However, as we are using upiu transactions that + * contains the lun index in its header, we need not to have its representation + * in the device tree. + */ +struct ufs_port { + struct device dev; + int id; + struct request_queue *q; +}; + +static inline struct ufs_port *dev_to_ufs_port(struct device *d) +{ + return container_of(d, struct ufs_port, dev); +} + +struct scsi_transport_template * +ufs_attach_transport(struct ufs_function_template *ft); +void ufs_release_transport(struct scsi_transport_template *t); +struct ufs_port *ufs_port_alloc(struct Scsi_Host *shost); +int ufs_port_add(struct ufs_port *port); +void ufs_port_free(struct ufs_port *port); +void ufs_port_delete(struct ufs_port *port); +void ufs_remove_host(struct Scsi_Host *shost); +#endif

[v2,1/8] scsi: Add ufs transport class

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